According to the basic theory on autofrettage and according to the 4th strength theory, several parameters and their relations are studied under ideal condition, including σej/σy, the equivalent stress of total stre...According to the basic theory on autofrettage and according to the 4th strength theory, several parameters and their relations are studied under ideal condition, including σej/σy, the equivalent stress of total stresses at elastoplastic juncture; σei/σy, the equivalent stress of total stresses at inside surface; σej＇/σy, the equivalent stress of residual stresses at elastoplastic juncture; σei＇/σy, the equivalent stress of residual stresses at inside surface; and p/σy, load-bearing capacity of an autofrettaged cylinder. By theoretical study on relations between the parameters, noticeable results and laws are achieved： to satisfy ｜σei＇｜=σy. the relation between kj and k is, k^2lnkj^2-k^2-kj^2＋2=0, when k→∞, kj = √e = 1.648 72, as based on the 3rd strength theory, where k is the outside/inside radius ratio of a cylinder, kj is the ratio of elastoplastic juncture radius to inside radius of a cylinder; If the plastic region covers the whole wall of a cylinder, for compressive yield not to occur after removing autofrettage pressure, the ultimate k is k=-2.218 46 as based on the 3rd strength theory; With k=2.218 46, a cylinder＇s ultimate load-bearing capacity equals its entire yield pressure, or p/σy=21nk/√3; The maximum and optimum load-bearing capacity of an autofrettaged cylinder is just 2 times the loading which an unautofrettaged cylinder can bear elastically, or p/σy=2（k^2-1）/√3 k^2, and the limit of the load-bearing capacity of an autofrettaged cylinder is also just 2 times that of an unautofrettaged cylinder. The conclusions are the same as based on the 3rd strength theory, but some equations are different from each other.展开更多
Autofrettage is an effective measure to even distribution of stresses and raise load-bearing capacity for （ultra-）high pressure apparatus. Currently, the research on autofrettage has focused mostly on specific engin...Autofrettage is an effective measure to even distribution of stresses and raise load-bearing capacity for （ultra-）high pressure apparatus. Currently, the research on autofrettage has focused mostly on specific engineering problems, while general theoretical study is rarely done. To discover the general law contained in autofrettage theory, by the aid of the authors’ previous work and according to the third strength theory, theoretical problems about autofrettage are studied including residual stresses and their equivalent stress, total stresses and their equivalent stress, etc. Because of the equation of optimum depth of plastic zone which is presented in the authors’ previous work, the equations for the residual stresses and their equivalent stress as well as the total stress and their equivalent stress are simplified greatly. Thus the law of distribution of the residual stresses and their equivalent stress as well as the total stress and their equivalent stress and the varying tendency of these stresses are discovered. The relation among various parameters are revealed. The safe and optimum load-bearing conditions for cylinders are obtained. According to the results obtained by theoretical analysis, it is shown that if the two parameters, namely ratio of outside to inside radius, k, and depth of plastic zone, kj, meet the equation of optimum depth of plastic zone, when the pressure contained in an autofrettaged cylinder is lower than two times the initial yield pressure of the unautofrettaged cylinder, the equivalent residual stress and the equivalent total stress at the inside surface as well as the elastic-plastic juncture of a cylinder are lower than yield strength. When an autofrettaged cylinder is subjected to just two times the initial yield pressure of the unautofrettaged cylinder, the equivalent total stress within the whole plastic zone is just identically equal to the yield strength, or it is a constant. The proposed research theoretically depicts the stress state of ultra-）high pressure autofrettaged cylinder more accurately and more reasonably and provides the reference for design of （ultra-）high pressure apparatus.展开更多
Soft grippers have great potential applications in daily life,since they can compliantly grasp soft and delicate objects.However,the highly elastic fingers of most soft grippers are prone to separate from each other w...Soft grippers have great potential applications in daily life,since they can compliantly grasp soft and delicate objects.However,the highly elastic fingers of most soft grippers are prone to separate from each other while grasping objects due to their low stiffness,thus reducing the grasping stability and load-bearing capacity.To tackle this problem,inspired from the venus flytrap plant,this work proposes a mutual-hook mechanism to restrain the separation and improve the grasping performance of soft fingers.The novel soft gripper design consists of three modules,a soft finger-cot,two Soft Hook Actuators(SHAs)and two sliding mechanisms.Here,the soft finger-cot covers on the soft finger,increasing the contact area with the target object,two SHAs are fixed to the left and right sides of the finger-cot,and the sliding mechanisms are designed to make SHAs stretch flexibly.Experiments demonstrate that the proposed design can restrain the separation of soft fingers substantially,and the soft fingers with the finger-cots can grasp objects three times heavier than the soft fingers without the proposed design.The proposed design can provide invaluable insights for soft fingers to restrain the separation while grasping,thus improving the grasping stability and the load-bearing capacity.展开更多
In several parts of the world, disposal of waste materials such as fly ash is a great problem. Application of waste materials as structural fills in foundations is one of the best solutions to disposal problems, becau...In several parts of the world, disposal of waste materials such as fly ash is a great problem. Application of waste materials as structural fills in foundations is one of the best solutions to disposal problems, because wastes can be used in large volumes in such applications. There may be difficulty due to poor load-bearing capacity of fly ash, especially when footing rests on the top of the fly ash fill slope. Inclusion of polymeric reinforcements as horizontal sheets within the fill may be one of the most viable solutions to improving the load-bearing capacity of reinforced fly ash slope, and it is particularly important for the situations where foundations need to be located either on the top of a slope or on slope itself. The present work is aimed at investigating the efficacy of a single layer of reinforcement in improving the lo, ad-bearing capacity when it gets incorporated within the body of a model fly ash embankment slope. An increase in load bearing capacity due to the incorporation of reinforcement in the model slope was found by conducting laboratory tests. Experimental results were compared by numerical values obtained using software GEO5 and PLAXIS.展开更多
The present study develops a novel type of active joint node-bolt fasten wedge(BFW)active joints,aiming to investigate the load-bearing capacity of a BFW joint in a quantitative way and put forward precise formulas fo...The present study develops a novel type of active joint node-bolt fasten wedge(BFW)active joints,aiming to investigate the load-bearing capacity of a BFW joint in a quantitative way and put forward precise formulas for its yield load and compression rigidity.To achieve this,indoor axial loading tests were conducted on two BFW joints,accompanied by a set of numerical simulations with the finite element approach implemented in ABAQUS.Parametric research was then conducted to assess the impact of various factors on the yield load and initial compression rigidity of BFW joints,leading to the derivation of precise calculation formulas for accurate prediction of these parameters.The key findings indicate that enhancing the bolt strength from 10.9 to 12.9 significantly improves mechanical performance.Under axial compression,the final bearing force,yield load,and initial compression rigidity increase by 0.86,1.06,and 0.15 times,respectively.Numerical models accurately predict joint behavior under axial force,confirming their reliability.Parameter studies reveal that increasing web and eaves thickness,bolt strength,and diameter improves bearing capacity,while splint thickness has little effect.The fitting formulas introduced can precisely estimate yield load and rigidity,providing practical value for engineering applications.展开更多
Roof pre-fracture poses a considerable risk during the re-mining of residual coal above abandoned roadways,threatening the safety of the mining faces.This study employs a Winkler foundation beam model for mechanical a...Roof pre-fracture poses a considerable risk during the re-mining of residual coal above abandoned roadways,threatening the safety of the mining faces.This study employs a Winkler foundation beam model for mechanical analysis of roof structures and adopts a multivariate nonlinear analysis approach to explore the synergistic load-bearing effects within the'coal pillar-support-backfill body'system during the fill and re-mining processes above these roadways.The findings demonstrate that backfill mining significantly reduces stress concentrations in coal pillars and reduces excessive bending moments in roofs near abandoned roadways.The roof deflection equation incorporates three critical factors affecting stability during backfill mining:the width of the coal pillar(L_(3)),the working resistance of the support(q_(z)),and the elastic foundation coefficient of the backfill material(kcÞ.Under single-factor conditions,the impact sequence on roof stability in the coal pillar zone is·k_(c)>L_(3)>q_(z).Further,multivariate nonlinear analysis reveals the interactions within the'coal-support-backfill'structure,indicating that in terms of roof control,the interaction terms are ordered as L_(3)·k_(c)>q_(z)·k_(c)>L_(3)q_(z).Therefore,priority should be given to adjusting the coal pillar width and backfill strength,followed by modifications to the support resistance and backfill strength during the recovery of abandoned roadways.An improved understanding of these interactions will help optimize strategies for the recovery of residual coal through abandoned roadways,thereby enhancing the stability and safety of mining operations under complex geological conditions.展开更多
Background:The trajectory of intrinsic capacity(IC)among the older population is characterized by its diversity and is predictive of adverse health outcomes such as disability,nursing home admission,decline in quality...Background:The trajectory of intrinsic capacity(IC)among the older population is characterized by its diversity and is predictive of adverse health outcomes such as disability,nursing home admission,decline in quality of life,and mortality.Gaining an understanding of the trajectory of IC and the factors that influence it is of paramount importance for fostering healthy aging.This research is focused on exploring the trajectory of IC among older adults in China and examining the factors that influence it.Methods:This observational longitudinal cohort study leveraged data from the China Health and Retirement Longitudinal Study(CHARLS),which was conducted in the years 2011,2013,and 2015.For the purpose of this analysis,a total of 2,233 participants who were aged 60 and over were included.A Growth Mixture Model(GMM)was utilized to define trajectory categories for IC.Influential factors were ascertained based on the health ecology model,and binary logistic regression analysis was utilized to investigate the factors linked with the different trajectory categories.Results:Two distinct trajectory classes of IC were identified:Class 1,the normal-stable group,encompassed 90.4%of the elderly population,while Class 2,the declining group,made up 9.6%.Advanced age and a history of stroke were found to be significantly associated with Class 2.High scores in activities of daily living(ADL),employment status,receiving primary or junior high school education,and residence in the East or Central regions of China were significantly linked with Class 1.Conclusion:The trajectory of IC among older Chinese adults is marked by its heterogeneity.Advanced age and a history of stroke are significant risk factors for a declining IC trajectory,while higher ADL scores,being employed,receiving primary or junior high school education,and residing in the East or Central regions of China are protective factors associated with a stable IC trajectory.Healthcare institutions must closely monitor IC levels and understand these trajectory patterns to implement personalized and targeted interventions promptly to maintain IC at a healthy level and advocate for healthy aging.展开更多
Designing materials with both structural load-bearing capacity and broadband electromagnetic(EM)wave absorption properties remains a significant challenge.In this work,SiOC/SiC/SiO_(2)composite with gyroid structures ...Designing materials with both structural load-bearing capacity and broadband electromagnetic(EM)wave absorption properties remains a significant challenge.In this work,SiOC/SiC/SiO_(2)composite with gyroid structures were prepared through digital light processing(DLP)3D printing,polymer-derived ceramics(PDCs),chemical vapor infiltration(CVI),and oxidation technologies.The incorporation of the CVISiC phase effectively increases the dissipation capability,while the synergistic interaction between the gyroid structure and SiO_(2)phase significantly improves impedance matching performance.The SiOC/SiC/SiO_(2)composite achieved a minimum reflection loss(RL min)of-62.2 d B at 4.3 mm,and the effective absorption bandwidth(EAB)covered the X-band,with a thickness range of 4.1 mm-4.65 mm.The CST simulation results explain the broadband and low-frequency absorption characteristics,with an EAB of 8.4 GHz(9.6-18 GHz)and an RL min of-21.5 dB at 5 GHz.The excellent EM wave attenuation performance is associated primarily with polarization loss,conduction loss,the gyroid structure's enhancement of multiple reflections and scattering of EM waves,and the resonance effect between the structural units.The SiOC/SiC/SiO_(2)composite also demonstrated strong mechanical properties,with a maximum compressive failure strength of 31.6 MPa in the height direction.This work opens novel prospects for the development of multifunctional structural wave-absorbing materials suitable for broadband microwave absorption and load-bearing properties.展开更多
Biochar, known as “black gold”, has garnered wide attention in various applications. However, the potential release of toxic organic compounds has raised environmental concerns, thereby limiting its safe and sustain...Biochar, known as “black gold”, has garnered wide attention in various applications. However, the potential release of toxic organic compounds has raised environmental concerns, thereby limiting its safe and sustainable application. Herein, we propose a distillation strategy to simultaneously detoxify biochar and enhance its redox functionality. Multi-factor correlation analysis identified 30 min as the optimal distillation time, which significantly increased the biochar's Brunauer-Emmett-Teller(BET) surface area(by 143%), improved hydrophilicity(with contact angle decreased by 3.8%), and effectively reduced the dissolved organic carbon(DOC) content of the biochar. Regarding the effect of distillation solvent, both water and acetic acid significantly enhanced the electron exchange capacity(EEC) of the biochar, with lactic acid exhibiting the best performance in improving the electron donating capacity(EDC). Meanwhile, distillation with acetic acid achieved optimal detoxification by effectively removing toxic organic compounds such as naphthalene, amines, and aromatic hydrocarbons. Further validation confirmed the good generalizability of this method to biochars derived from various feedstocks. Techno-economic analysis showed a 98.7% reduction in water consumption and 22.9%-62.5% cost savings compared to traditional washing methods. This work highlights distillation as an efficient, eco-friendly, and cost-effective method to enhance biochar safety and redox functionality, thereby advancing its sustainable applications.展开更多
Background:Intrinsic capacity reflects the overall health status of older adults and decline in intrinsic abilities can lead to adverse health outcomes.However,empirical studies examining the association between digit...Background:Intrinsic capacity reflects the overall health status of older adults and decline in intrinsic abilities can lead to adverse health outcomes.However,empirical studies examining the association between digital health literacy,health-promoting lifestyles and intrinsic capacity are scarce.Methods:A cross-sectional study was conducted.Using convenience sampling method,371 older adults were recruited from communities.Multidimensional intrinsic capacity,digital health literacy,health promoting lifestyle and sociodemographic information were measured.Results:The intrinsic capacity of older adults scored 3.75±1.10.The prevalences of declined cognitive capacity,psychological capacity,sensory capacity,vitality,and locomotor capacity were 13.7%,24.3%,19.1%,14.8%,53.1%,respectively.The multiple regression analysis revealed that age(β=−0.253),only living with children and/or grandchildren(β=0.249),current working status(β=−0.132),number of chronic diseases(β=−0.149),frequency of Internet usage(β=0.193),the domain of ability to acquire and evaluate digital health information(β=0.197)in digital health literacy,and the domain of nutrition(β=0.171)in health-promoting lifestyle were the significant factors influencing intrinsic capacity,explaining 27.1%of the variance.Conclusion:Digital health literacy and health-promoting lifestyle have a significant impact on intrinsic capacity.Enhancing digital health literacy and advocating a health-promoting lifestyle are critical to promoting intrinsic capacity for community-dwelling older adults.展开更多
Research on high-speed railways is a relatively new yet highly significant field in Vietnam.Among its key components,train control signaling plays a critical role,as it directly affects various interconnected systems,...Research on high-speed railways is a relatively new yet highly significant field in Vietnam.Among its key components,train control signaling plays a critical role,as it directly affects various interconnected systems,including infrastructure,traction power supply,operational planning,and overall railway safety.This article focuses on evaluating the capacity of the line based on the types of signals suitable for high-speed railways that have been effectively implemented in several European countries and successfully adapted in China.The research and simulation are conducted using MATLAB software,a reliable and widely adopted tool in the scientific community.The findings demonstrate that under normal conditions,the European Railway Traffic Management System/European Train Control System(ERTMS/ETCS)Level 2 signaling can support up to 23.7485 trains/hour/direction.Meanwhile,ERTMS/ETCS Level 3 with full moving block can accommodate up to 30.8735 trains/hour/direction,and ERTMS/ETCS Level 3 with fixed virtual blocks up to 29.4694 trains/hour/direction.In emergency scenarios,ERTMS/ETCS Level 3 with full moving block reduces headway by 33.27%compared to CTCS Level 3,while ERTMS/ETCS Level 3 with fixed virtual blocks achieves a 28.78%reduction.Overall,the ERTMS/ETCS Level 3 emerges as a state-of-the-art signaling technology offering high capacity and operational efficiency,and is recommended as a forward-looking solution for future implementation in Vietnam.展开更多
Purpose-This study investigates the impact of flagship trains on high-speed railway capacity utilization and develops a brand value-oriented optimization framework that balances service quality enhancement with operat...Purpose-This study investigates the impact of flagship trains on high-speed railway capacity utilization and develops a brand value-oriented optimization framework that balances service quality enhancement with operational efficiency.Design/methodology/approach-A mathematical optimization model based on integer programming is developed,incorporating flagship train constraints into capacity optimization.Case studies compare scenarios with and without flagship train considerations using the Beijing-Shanghai High-Speed Railway data across 20 experimental groups.Findings-Operating flagship trains with hourly departure constraints results in an average decrease of 0.9 trains and an 8.4%reduction in capacity utilization rate.When scheduling 2 flagship trains within a 2-h timeframe,capacity utilization decreases from 86.43%to 83.73%,quantifying the trade-off between brand positioning and operational capacity.Originality/value-This research provides the first quantitative framework for brand value-oriented railway capacity optimization,establishing clear definitions for flagship trains and mathematical foundations for evaluating service quality versus efficiency trade-offs.The findings offer practical decision support for railway operators balancing competitive positioning with capacity maximization.展开更多
China Standardization:Can you please briefly introduce ISO,its international standards as well as your scope of work?Rachel Miller Prada:ISO is an independent non-governmental organization dedicated to developing inte...China Standardization:Can you please briefly introduce ISO,its international standards as well as your scope of work?Rachel Miller Prada:ISO is an independent non-governmental organization dedicated to developing international standards.Currently,ISO has 175 member bodies,representing 175 countries that participate in its standard development work.We have a portfolio of over 24,000 international standards,with around 100 new standards issued or existing ones revised every month.The ultimate goal of our standardization work is to support the achievement of the United Nations Sustainable Development Goals(SDGs).Every standard we develop and every task I undertake in my role contributes to these global objectives.展开更多
To achieve the goals of sustainable development of the energy system and the construction of a lowcarbon society,this study proposes a multi-energy storage collaborative optimization strategy for industrial park that ...To achieve the goals of sustainable development of the energy system and the construction of a lowcarbon society,this study proposes a multi-energy storage collaborative optimization strategy for industrial park that integrates the laddered carbon trading mechanism with demand response.Firstly,a dual dimensional DR model is constructed based on the characteristics of load elasticity.The alternativeDRenables flexible substitution of energy loads through complementary conversion of electricity/heat/cold multi-energy sources,while the price DR relies on timeof-use electricity price signals to guide load spatiotemporal migration;Secondly,the LCT mechanism is introduced to achieve optimal carbon emission costs through a tiered carbon quota allocation mechanism.On this basis,an optimization decision model is established with the core objective of maximizing the annual net profit of the park.The objective function takes into account energy sales revenue,generator unit costs,and investment and operation costs of multiple types of energy storage facilities.Themodel constraint system covers three key dimensions:dynamic operation constraints of power generation units,including unit output limits,ramping capability,and minimum start-stop time;the physical boundary of an electric/hot/cold multi-energy storage system involves energy storage capacity and charge/discharge efficiency;The multi-energy network coupling balance equation ensures that the energy conversion and transmission process satisfies the law of conservation of energy.Using CPLEX mathematical programming solver for simulation verification,construct an energy storage capacity configuration decision process that includes LCT-DR synergistic effect.The research results show that compared with the traditional single energy storage configuration mode,this strategy effectively enhances the economic feasibility and engineering practicality of industrial park operation by coordinating demand side resource scheduling and finely controlling carbon costs,while maintaining stable system operation.Its methodological framework provides a technical path that combines theoretical rigor and practical operability for the low-carbon transformation of regional integrated energy systems.展开更多
Objective:To explore the application effect of combined exercise intervention based on the hospital-community-family model on intrinsic capacity in elderly patients with diabetes mellitus complicated by chronic kidney...Objective:To explore the application effect of combined exercise intervention based on the hospital-community-family model on intrinsic capacity in elderly patients with diabetes mellitus complicated by chronic kidney disease.Methods:Using convenience sampling,100 elderly patients with diabetes mellitus complicated by chronic kidney disease who received treatment in the endocrinology department of a tertiary A-level hospital from May 2024 to May 2025 were selected as the study subjects.They were randomly divided into an experimental group(50 cases)and a control group(50 cases)using a random number table method.The control group received routine health education and telephone follow-up,while the experimental group,in addition to the control group’s interventions,underwent combined exercise intervention based on the hospital-community-family model.Remote medical guidance was utilized to monitor and study the application effect of exercise intervention on intrinsic capacity in elderly patients with diabetes mellitus complicated by chronic kidney disease.Fasting blood glucose,2-hour postprandial blood glucose,glomerular filtration rate,6-minute walk distance,and scores in five dimensions of intrinsic capacity(exercise,cognition,psychology,vitality,and sensation)were measured before the intervention,at 4 weeks of intervention,and at 12 weeks of intervention for both groups.Results:Before the exercise intervention,there were no statistically significant differences(p>0.05)between the two groups in terms of fasting blood glucose,2-hour postprandial blood glucose,glomerular filtration rate,6-minute walk distance,and scores across five dimensions of intrinsic capacity:mobility,cognition,psychology,vitality,and sensation.After 12 weeks of intervention,the experimental group demonstrated significantly higher scores than the control group in glomerular filtration rate,6-minute walk distance,and the dimensions of mobility,cognition,and vitality within intrinsic capacity,with all differences being statistically significant(p<0.05).Conversely,the experimental group showed significantly lower scores than the control group in fasting blood glucose,2-hour postprandial blood glucose,and the psychological dimension of intrinsic capacity,with these differences also being statistically significant(p<0.05).Conclusion:Continuous nursing care utilizing telemedicine based on a hospital-community-family model combined with exercise intervention can effectively enhance exercise tolerance and intrinsic capacity in elderly patients with diabetes mellitus complicated by chronic kidney disease,thereby improving their quality of life.The effectiveness of the intervention is positively correlated with the duration of the intervention.展开更多
Root-inspired anchorage systems in the field of bio-inspired geotechnics are renowned for enhancing the pullout capacity of traditional geotechnical anchorage systems by simulating the morphology and architecture of p...Root-inspired anchorage systems in the field of bio-inspired geotechnics are renowned for enhancing the pullout capacity of traditional geotechnical anchorage systems by simulating the morphology and architecture of plant root systems.However,limited studies have explored their practical applications,particularly in improving slope stability.To fill this gap,this study investigates the reinforcement effect of root-inspired anchors on slope stabilization using transparent soil modeling and 3D-printed anchors,and examines the impact of anchor branching patterns(i.e.branching numbers,branching angle,and branching nodes)on slope bearing capacity,shear band evolution,and temporal and spatial variation of slope deformation.The results show that peak slope bearing capacity increases with branching numbers and branching angles,correlating with the envelope area of the curved shear band.Upper anchors result in step-like deflections in the shear band near the trailing edge,while lower anchors convert the upward concave shear band into an upward convex one,thus increasing the slope bearing capacity.Slope deformation is minimized with intermediate branching parameters,such as a branching number of 4 and a branching angle of 45°.The anchor reinforcement mechanisms,i.e.anchor rod shear resistance,interface friction,anchor pullout capacity,and plate tightening effects,are comprehensively discussed,and the installation effects resulting from compromise slope modeling are identified as the contributors.These findings shed light on the failure process of root-inspired anchors reinforced slopes and provide a preliminary reference for potential applications,especially for the tradeoff between anchor branching,slope deformation,and slope stability.展开更多
Micro-sized anatase TiO_(2) displays inferior capacity as cathode material for magnesium ion batteries because of the higher diffusion energy barrier of Mg^(2+)in anatase TiO_(2) lattice.Herein,we report that nanosize...Micro-sized anatase TiO_(2) displays inferior capacity as cathode material for magnesium ion batteries because of the higher diffusion energy barrier of Mg^(2+)in anatase TiO_(2) lattice.Herein,we report that nanosized anatase TiO_(2) exposed(001)facet doubles the capacity compared to the micro-sized sample ascribed to the interfacial Mg^(2+)ion storage.First-principles calculations reveal that the diffusion energy barrier of Mg^(2+)on the(001)facet is significantly lower than those in the bulk phase and on(100)facet,and the adsorption energy of Mg^(2+)on the(001)facet is also considerably lower than that on(100)facet,which guarantees superior interfacial Mg^(2+)storage of(001)facet.Moreover,anatase TiO_(2) exposed(001)facet displays a significantly higher capacity of 312.9 mAh g^(−1) in Mg-Li dual-salt electrolyte compared to 234.3 mAh g^(−1) in Li salt electrolyte.The adsorption energies of Mg^(2+)on(001)facet are much lower than the adsorption energies of Li+on(001)facet,implying that the Mg^(2+)ion interfacial storage is more favorable.These results highlight that controlling the crystal facet of the nanocrystals effectively enhances the interfacial storage of multivalent ions.This work offers valuable guidance for the rational design of high-capacity storage systems.展开更多
In this paper,we propose and analyze two second-order accurate finite difference schemes for the one-dimensional heat equation with concentrated capacity on a computa-tional domain=[a,b].We first transform the target ...In this paper,we propose and analyze two second-order accurate finite difference schemes for the one-dimensional heat equation with concentrated capacity on a computa-tional domain=[a,b].We first transform the target equation into the standard heat equation on the domain excluding the singular point equipped with an inner interface matching(IIM)condition on the singular point x=ξ∈(a,b),then adopt Taylor’s ex-pansion to approximate the IIM condition at the singular point and apply second-order finite difference method to approximate the standard heat equation at the nonsingular points.This discrete procedure allows us to choose different grid sizes to partition the two sub-domains[a,ξ]and[ξ,b],which ensures that x=ξ is a grid point,and hence the pro-posed schemes can be generalized to the heat equation with more than one concentrated capacities.We prove that the two proposed schemes are uniquely solvable.And through in-depth analysis of the local truncation errors,we rigorously prove that the two schemes are second-order accurate both in temporal and spatial directions in the maximum norm without any constraint on the grid ratio.Numerical experiments are carried out to verify our theoretical conclusions.展开更多
Cartilage is well lubricated over a lifetime and this phenomenon is attributed to both of the surface hydration lubrication and the matrix load-bearing capacity.Lubricious hydrogels with a layered structure are design...Cartilage is well lubricated over a lifetime and this phenomenon is attributed to both of the surface hydration lubrication and the matrix load-bearing capacity.Lubricious hydrogels with a layered structure are designed to mimic cartilage as potential replacements.While many studies have concentrated on improving surface hydration to reduce friction,few have experimentally detected the relationship between load-bearing capacity of hydrogels and their interface friction behavior.In this work,a bilayer hydrogel,serving as a cartilage prototype consisted of a top thick hydrated polymer brush layer and a bottom hydrogel matrix with tunable modulus was designed to investigate this relationship.The coefficient of friction(COF,μ)is defined as the sum of interfacial component(μInt)and deformation/hysteresis component(μHyst).The presence of the top hydration layer effectively dissipates contact stress and reduces the interface interaction(μInt),leading to a stable and low COF.The contribution of mechanical deformation(μHyst)during the sliding shearing process to COF can be significantly reduced by increasing the local mechanical modulus,thereby enhancing the load-bearing capacity.These results show that the strategy of coupling surface hydration layer with a high load-bearing matrix can indeed enhance the lubrication performance of hydrogel cartilage prototypes,and implies a promising routine for designing robust soft matter lubrication system and friction-control devices.展开更多
Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships w...Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships with antioxidant activity and oxidative stability,gas chromatography-mass spectrometry was performed to characterize the associated fatty acid profiles.The antioxidant activity of vegetable oils,based on their DPPH-scavenging capacity(expressed as IC_(50) values),was used to assess their impact on human health,and their oxidative stability was characterized by performing lipid oxidation analysis to determine the oxidative induction time of fats and oils.In addition,correlation analyses were performed to examine associations between the fatty acid composition of the oils and DPPH-scavenging capacity and oxidative stability.The results revealed that among the assessed oils,coffee seed oil has the highest saturated fatty acid content(355.10 mg/g),whereas Garddenia jaminoides oil has the highest unsaturated fatty acid content(844.84 mg/g).Coffee seed oil was also found have the lowest DPPH IC_(50) value(2.30 mg/mL)and the longest oxidation induction time(17.09 h).Correlation analysis revealed a significant linear relationship(P<0.05)between oxidative stability and unsaturated fatty acid content,with lower contents tending to be associated with better oxidative stability.The findings of this study provide reference data for the screening of functional edible vegetable oils.展开更多
文摘According to the basic theory on autofrettage and according to the 4th strength theory, several parameters and their relations are studied under ideal condition, including σej/σy, the equivalent stress of total stresses at elastoplastic juncture; σei/σy, the equivalent stress of total stresses at inside surface; σej＇/σy, the equivalent stress of residual stresses at elastoplastic juncture; σei＇/σy, the equivalent stress of residual stresses at inside surface; and p/σy, load-bearing capacity of an autofrettaged cylinder. By theoretical study on relations between the parameters, noticeable results and laws are achieved： to satisfy ｜σei＇｜=σy. the relation between kj and k is, k^2lnkj^2-k^2-kj^2＋2=0, when k→∞, kj = √e = 1.648 72, as based on the 3rd strength theory, where k is the outside/inside radius ratio of a cylinder, kj is the ratio of elastoplastic juncture radius to inside radius of a cylinder; If the plastic region covers the whole wall of a cylinder, for compressive yield not to occur after removing autofrettage pressure, the ultimate k is k=-2.218 46 as based on the 3rd strength theory; With k=2.218 46, a cylinder＇s ultimate load-bearing capacity equals its entire yield pressure, or p/σy=21nk/√3; The maximum and optimum load-bearing capacity of an autofrettaged cylinder is just 2 times the loading which an unautofrettaged cylinder can bear elastically, or p/σy=2（k^2-1）/√3 k^2, and the limit of the load-bearing capacity of an autofrettaged cylinder is also just 2 times that of an unautofrettaged cylinder. The conclusions are the same as based on the 3rd strength theory, but some equations are different from each other.
基金supported by Scientific Research Fund of Hunan Provincial Education Department(Grant No. 12A087)Innovation Fund for Technology Based Firms(Grant No. 09C26214305047)
文摘Autofrettage is an effective measure to even distribution of stresses and raise load-bearing capacity for （ultra-）high pressure apparatus. Currently, the research on autofrettage has focused mostly on specific engineering problems, while general theoretical study is rarely done. To discover the general law contained in autofrettage theory, by the aid of the authors’ previous work and according to the third strength theory, theoretical problems about autofrettage are studied including residual stresses and their equivalent stress, total stresses and their equivalent stress, etc. Because of the equation of optimum depth of plastic zone which is presented in the authors’ previous work, the equations for the residual stresses and their equivalent stress as well as the total stress and their equivalent stress are simplified greatly. Thus the law of distribution of the residual stresses and their equivalent stress as well as the total stress and their equivalent stress and the varying tendency of these stresses are discovered. The relation among various parameters are revealed. The safe and optimum load-bearing conditions for cylinders are obtained. According to the results obtained by theoretical analysis, it is shown that if the two parameters, namely ratio of outside to inside radius, k, and depth of plastic zone, kj, meet the equation of optimum depth of plastic zone, when the pressure contained in an autofrettaged cylinder is lower than two times the initial yield pressure of the unautofrettaged cylinder, the equivalent residual stress and the equivalent total stress at the inside surface as well as the elastic-plastic juncture of a cylinder are lower than yield strength. When an autofrettaged cylinder is subjected to just two times the initial yield pressure of the unautofrettaged cylinder, the equivalent total stress within the whole plastic zone is just identically equal to the yield strength, or it is a constant. The proposed research theoretically depicts the stress state of ultra-）high pressure autofrettaged cylinder more accurately and more reasonably and provides the reference for design of （ultra-）high pressure apparatus.
基金funded by the National Natural Science Foundation of China under Grant 62073305 and the Natural Science Foundation of Hubei Province under Grant 2022CFA041.
文摘Soft grippers have great potential applications in daily life,since they can compliantly grasp soft and delicate objects.However,the highly elastic fingers of most soft grippers are prone to separate from each other while grasping objects due to their low stiffness,thus reducing the grasping stability and load-bearing capacity.To tackle this problem,inspired from the venus flytrap plant,this work proposes a mutual-hook mechanism to restrain the separation and improve the grasping performance of soft fingers.The novel soft gripper design consists of three modules,a soft finger-cot,two Soft Hook Actuators(SHAs)and two sliding mechanisms.Here,the soft finger-cot covers on the soft finger,increasing the contact area with the target object,two SHAs are fixed to the left and right sides of the finger-cot,and the sliding mechanisms are designed to make SHAs stretch flexibly.Experiments demonstrate that the proposed design can restrain the separation of soft fingers substantially,and the soft fingers with the finger-cots can grasp objects three times heavier than the soft fingers without the proposed design.The proposed design can provide invaluable insights for soft fingers to restrain the separation while grasping,thus improving the grasping stability and the load-bearing capacity.
文摘In several parts of the world, disposal of waste materials such as fly ash is a great problem. Application of waste materials as structural fills in foundations is one of the best solutions to disposal problems, because wastes can be used in large volumes in such applications. There may be difficulty due to poor load-bearing capacity of fly ash, especially when footing rests on the top of the fly ash fill slope. Inclusion of polymeric reinforcements as horizontal sheets within the fill may be one of the most viable solutions to improving the load-bearing capacity of reinforced fly ash slope, and it is particularly important for the situations where foundations need to be located either on the top of a slope or on slope itself. The present work is aimed at investigating the efficacy of a single layer of reinforcement in improving the lo, ad-bearing capacity when it gets incorporated within the body of a model fly ash embankment slope. An increase in load bearing capacity due to the incorporation of reinforcement in the model slope was found by conducting laboratory tests. Experimental results were compared by numerical values obtained using software GEO5 and PLAXIS.
基金the financial support provided by Beijing Natural Science Foundation(Grant No.8222005)the Natural Science Foundation of China(Grant No.51978018)Science and Technology Funding Scheme for the Third Construction Engineering Company Ltd.of China Construction Second Engineering Bureau(Grant No.CSCEC2b3c-2021-K-65).
文摘The present study develops a novel type of active joint node-bolt fasten wedge(BFW)active joints,aiming to investigate the load-bearing capacity of a BFW joint in a quantitative way and put forward precise formulas for its yield load and compression rigidity.To achieve this,indoor axial loading tests were conducted on two BFW joints,accompanied by a set of numerical simulations with the finite element approach implemented in ABAQUS.Parametric research was then conducted to assess the impact of various factors on the yield load and initial compression rigidity of BFW joints,leading to the derivation of precise calculation formulas for accurate prediction of these parameters.The key findings indicate that enhancing the bolt strength from 10.9 to 12.9 significantly improves mechanical performance.Under axial compression,the final bearing force,yield load,and initial compression rigidity increase by 0.86,1.06,and 0.15 times,respectively.Numerical models accurately predict joint behavior under axial force,confirming their reliability.Parameter studies reveal that increasing web and eaves thickness,bolt strength,and diameter improves bearing capacity,while splint thickness has little effect.The fitting formulas introduced can precisely estimate yield load and rigidity,providing practical value for engineering applications.
基金support from National Natural Science Foundation of China(Grant No.52474142)The National Science Fund for Distinguished Young Scholars(No.51925402),Chinathe China Postdoctoral Science Foundation(Grant No.2021M702049).
文摘Roof pre-fracture poses a considerable risk during the re-mining of residual coal above abandoned roadways,threatening the safety of the mining faces.This study employs a Winkler foundation beam model for mechanical analysis of roof structures and adopts a multivariate nonlinear analysis approach to explore the synergistic load-bearing effects within the'coal pillar-support-backfill body'system during the fill and re-mining processes above these roadways.The findings demonstrate that backfill mining significantly reduces stress concentrations in coal pillars and reduces excessive bending moments in roofs near abandoned roadways.The roof deflection equation incorporates three critical factors affecting stability during backfill mining:the width of the coal pillar(L_(3)),the working resistance of the support(q_(z)),and the elastic foundation coefficient of the backfill material(kcÞ.Under single-factor conditions,the impact sequence on roof stability in the coal pillar zone is·k_(c)>L_(3)>q_(z).Further,multivariate nonlinear analysis reveals the interactions within the'coal-support-backfill'structure,indicating that in terms of roof control,the interaction terms are ordered as L_(3)·k_(c)>q_(z)·k_(c)>L_(3)q_(z).Therefore,priority should be given to adjusting the coal pillar width and backfill strength,followed by modifications to the support resistance and backfill strength during the recovery of abandoned roadways.An improved understanding of these interactions will help optimize strategies for the recovery of residual coal through abandoned roadways,thereby enhancing the stability and safety of mining operations under complex geological conditions.
基金China Health and Retirement Longitudinal Study(CHARLS)the 2022-2023 Nursing Research Project of Chinese Medical Association Publishing House(Grant No.CMAPH-NRD2022024)。
文摘Background:The trajectory of intrinsic capacity(IC)among the older population is characterized by its diversity and is predictive of adverse health outcomes such as disability,nursing home admission,decline in quality of life,and mortality.Gaining an understanding of the trajectory of IC and the factors that influence it is of paramount importance for fostering healthy aging.This research is focused on exploring the trajectory of IC among older adults in China and examining the factors that influence it.Methods:This observational longitudinal cohort study leveraged data from the China Health and Retirement Longitudinal Study(CHARLS),which was conducted in the years 2011,2013,and 2015.For the purpose of this analysis,a total of 2,233 participants who were aged 60 and over were included.A Growth Mixture Model(GMM)was utilized to define trajectory categories for IC.Influential factors were ascertained based on the health ecology model,and binary logistic regression analysis was utilized to investigate the factors linked with the different trajectory categories.Results:Two distinct trajectory classes of IC were identified:Class 1,the normal-stable group,encompassed 90.4%of the elderly population,while Class 2,the declining group,made up 9.6%.Advanced age and a history of stroke were found to be significantly associated with Class 2.High scores in activities of daily living(ADL),employment status,receiving primary or junior high school education,and residence in the East or Central regions of China were significantly linked with Class 1.Conclusion:The trajectory of IC among older Chinese adults is marked by its heterogeneity.Advanced age and a history of stroke are significant risk factors for a declining IC trajectory,while higher ADL scores,being employed,receiving primary or junior high school education,and residing in the East or Central regions of China are protective factors associated with a stable IC trajectory.Healthcare institutions must closely monitor IC levels and understand these trajectory patterns to implement personalized and targeted interventions promptly to maintain IC at a healthy level and advocate for healthy aging.
基金financially supported by National Natural Science Foundation of China(Grant Nos.12141203,52202083,W2421013)the Natural Science Foundation Project of Shaanxi Province(Grant No.2024JC-YBMS-450)+1 种基金the Sichuan Science and Technology Program(Grant No.2024YFHZ0265)the Open Project of High-end Equipment Advanced Materials and Manufacturing Technology Laboratory(Grant No.2023KFKT0005)。
文摘Designing materials with both structural load-bearing capacity and broadband electromagnetic(EM)wave absorption properties remains a significant challenge.In this work,SiOC/SiC/SiO_(2)composite with gyroid structures were prepared through digital light processing(DLP)3D printing,polymer-derived ceramics(PDCs),chemical vapor infiltration(CVI),and oxidation technologies.The incorporation of the CVISiC phase effectively increases the dissipation capability,while the synergistic interaction between the gyroid structure and SiO_(2)phase significantly improves impedance matching performance.The SiOC/SiC/SiO_(2)composite achieved a minimum reflection loss(RL min)of-62.2 d B at 4.3 mm,and the effective absorption bandwidth(EAB)covered the X-band,with a thickness range of 4.1 mm-4.65 mm.The CST simulation results explain the broadband and low-frequency absorption characteristics,with an EAB of 8.4 GHz(9.6-18 GHz)and an RL min of-21.5 dB at 5 GHz.The excellent EM wave attenuation performance is associated primarily with polarization loss,conduction loss,the gyroid structure's enhancement of multiple reflections and scattering of EM waves,and the resonance effect between the structural units.The SiOC/SiC/SiO_(2)composite also demonstrated strong mechanical properties,with a maximum compressive failure strength of 31.6 MPa in the height direction.This work opens novel prospects for the development of multifunctional structural wave-absorbing materials suitable for broadband microwave absorption and load-bearing properties.
基金supported by the National Key R&D Program of China (Grant No.2025YFE0100700)the National Natural Science Foundation of China (Grant No.52270138)the International Science and Technology Cooperation Program of Shanghai Science and Technology Innovation Action Plan (Grant No.22230712200)。
文摘Biochar, known as “black gold”, has garnered wide attention in various applications. However, the potential release of toxic organic compounds has raised environmental concerns, thereby limiting its safe and sustainable application. Herein, we propose a distillation strategy to simultaneously detoxify biochar and enhance its redox functionality. Multi-factor correlation analysis identified 30 min as the optimal distillation time, which significantly increased the biochar's Brunauer-Emmett-Teller(BET) surface area(by 143%), improved hydrophilicity(with contact angle decreased by 3.8%), and effectively reduced the dissolved organic carbon(DOC) content of the biochar. Regarding the effect of distillation solvent, both water and acetic acid significantly enhanced the electron exchange capacity(EEC) of the biochar, with lactic acid exhibiting the best performance in improving the electron donating capacity(EDC). Meanwhile, distillation with acetic acid achieved optimal detoxification by effectively removing toxic organic compounds such as naphthalene, amines, and aromatic hydrocarbons. Further validation confirmed the good generalizability of this method to biochars derived from various feedstocks. Techno-economic analysis showed a 98.7% reduction in water consumption and 22.9%-62.5% cost savings compared to traditional washing methods. This work highlights distillation as an efficient, eco-friendly, and cost-effective method to enhance biochar safety and redox functionality, thereby advancing its sustainable applications.
基金funded by the College Students’Innovation and Entrepreneurship Program(X2024110650385).
文摘Background:Intrinsic capacity reflects the overall health status of older adults and decline in intrinsic abilities can lead to adverse health outcomes.However,empirical studies examining the association between digital health literacy,health-promoting lifestyles and intrinsic capacity are scarce.Methods:A cross-sectional study was conducted.Using convenience sampling method,371 older adults were recruited from communities.Multidimensional intrinsic capacity,digital health literacy,health promoting lifestyle and sociodemographic information were measured.Results:The intrinsic capacity of older adults scored 3.75±1.10.The prevalences of declined cognitive capacity,psychological capacity,sensory capacity,vitality,and locomotor capacity were 13.7%,24.3%,19.1%,14.8%,53.1%,respectively.The multiple regression analysis revealed that age(β=−0.253),only living with children and/or grandchildren(β=0.249),current working status(β=−0.132),number of chronic diseases(β=−0.149),frequency of Internet usage(β=0.193),the domain of ability to acquire and evaluate digital health information(β=0.197)in digital health literacy,and the domain of nutrition(β=0.171)in health-promoting lifestyle were the significant factors influencing intrinsic capacity,explaining 27.1%of the variance.Conclusion:Digital health literacy and health-promoting lifestyle have a significant impact on intrinsic capacity.Enhancing digital health literacy and advocating a health-promoting lifestyle are critical to promoting intrinsic capacity for community-dwelling older adults.
文摘Research on high-speed railways is a relatively new yet highly significant field in Vietnam.Among its key components,train control signaling plays a critical role,as it directly affects various interconnected systems,including infrastructure,traction power supply,operational planning,and overall railway safety.This article focuses on evaluating the capacity of the line based on the types of signals suitable for high-speed railways that have been effectively implemented in several European countries and successfully adapted in China.The research and simulation are conducted using MATLAB software,a reliable and widely adopted tool in the scientific community.The findings demonstrate that under normal conditions,the European Railway Traffic Management System/European Train Control System(ERTMS/ETCS)Level 2 signaling can support up to 23.7485 trains/hour/direction.Meanwhile,ERTMS/ETCS Level 3 with full moving block can accommodate up to 30.8735 trains/hour/direction,and ERTMS/ETCS Level 3 with fixed virtual blocks up to 29.4694 trains/hour/direction.In emergency scenarios,ERTMS/ETCS Level 3 with full moving block reduces headway by 33.27%compared to CTCS Level 3,while ERTMS/ETCS Level 3 with fixed virtual blocks achieves a 28.78%reduction.Overall,the ERTMS/ETCS Level 3 emerges as a state-of-the-art signaling technology offering high capacity and operational efficiency,and is recommended as a forward-looking solution for future implementation in Vietnam.
基金funded by the Science and Technology Research and Development Program Project of China Railway Group Co.,Ltd,grant number P2024X002the China Academy of Railway Sciences Corporation Limited,grant number 2024YJ154.
文摘Purpose-This study investigates the impact of flagship trains on high-speed railway capacity utilization and develops a brand value-oriented optimization framework that balances service quality enhancement with operational efficiency.Design/methodology/approach-A mathematical optimization model based on integer programming is developed,incorporating flagship train constraints into capacity optimization.Case studies compare scenarios with and without flagship train considerations using the Beijing-Shanghai High-Speed Railway data across 20 experimental groups.Findings-Operating flagship trains with hourly departure constraints results in an average decrease of 0.9 trains and an 8.4%reduction in capacity utilization rate.When scheduling 2 flagship trains within a 2-h timeframe,capacity utilization decreases from 86.43%to 83.73%,quantifying the trade-off between brand positioning and operational capacity.Originality/value-This research provides the first quantitative framework for brand value-oriented railway capacity optimization,establishing clear definitions for flagship trains and mathematical foundations for evaluating service quality versus efficiency trade-offs.The findings offer practical decision support for railway operators balancing competitive positioning with capacity maximization.
文摘China Standardization:Can you please briefly introduce ISO,its international standards as well as your scope of work?Rachel Miller Prada:ISO is an independent non-governmental organization dedicated to developing international standards.Currently,ISO has 175 member bodies,representing 175 countries that participate in its standard development work.We have a portfolio of over 24,000 international standards,with around 100 new standards issued or existing ones revised every month.The ultimate goal of our standardization work is to support the achievement of the United Nations Sustainable Development Goals(SDGs).Every standard we develop and every task I undertake in my role contributes to these global objectives.
基金funded by Science and Technology Projects from State Grid Corporation of China,(Research on Adaptive Balance Optimization and Simulation Technology of Industrial community Energy System with High Proportion of Distributed Energy,No.:5100-202355752A-3-4-SY).
文摘To achieve the goals of sustainable development of the energy system and the construction of a lowcarbon society,this study proposes a multi-energy storage collaborative optimization strategy for industrial park that integrates the laddered carbon trading mechanism with demand response.Firstly,a dual dimensional DR model is constructed based on the characteristics of load elasticity.The alternativeDRenables flexible substitution of energy loads through complementary conversion of electricity/heat/cold multi-energy sources,while the price DR relies on timeof-use electricity price signals to guide load spatiotemporal migration;Secondly,the LCT mechanism is introduced to achieve optimal carbon emission costs through a tiered carbon quota allocation mechanism.On this basis,an optimization decision model is established with the core objective of maximizing the annual net profit of the park.The objective function takes into account energy sales revenue,generator unit costs,and investment and operation costs of multiple types of energy storage facilities.Themodel constraint system covers three key dimensions:dynamic operation constraints of power generation units,including unit output limits,ramping capability,and minimum start-stop time;the physical boundary of an electric/hot/cold multi-energy storage system involves energy storage capacity and charge/discharge efficiency;The multi-energy network coupling balance equation ensures that the energy conversion and transmission process satisfies the law of conservation of energy.Using CPLEX mathematical programming solver for simulation verification,construct an energy storage capacity configuration decision process that includes LCT-DR synergistic effect.The research results show that compared with the traditional single energy storage configuration mode,this strategy effectively enhances the economic feasibility and engineering practicality of industrial park operation by coordinating demand side resource scheduling and finely controlling carbon costs,while maintaining stable system operation.Its methodological framework provides a technical path that combines theoretical rigor and practical operability for the low-carbon transformation of regional integrated energy systems.
基金2024 Medical Science Research Project Plan of Hebei Province:Research on the Rehabilitation Effect of Combined Exercise Intervention Based on a Hospital-Community-Family Model for Elderly Patients with Chronic Diseases(Project No.:20240083)Youth Science and Technology Project of the Hebei Provincial Health Department:Research on the Standardization Level of Self-Management in Patients with Diabetic Foot and Related Factors Affecting Wound Healing(Project No.:20190002)。
文摘Objective:To explore the application effect of combined exercise intervention based on the hospital-community-family model on intrinsic capacity in elderly patients with diabetes mellitus complicated by chronic kidney disease.Methods:Using convenience sampling,100 elderly patients with diabetes mellitus complicated by chronic kidney disease who received treatment in the endocrinology department of a tertiary A-level hospital from May 2024 to May 2025 were selected as the study subjects.They were randomly divided into an experimental group(50 cases)and a control group(50 cases)using a random number table method.The control group received routine health education and telephone follow-up,while the experimental group,in addition to the control group’s interventions,underwent combined exercise intervention based on the hospital-community-family model.Remote medical guidance was utilized to monitor and study the application effect of exercise intervention on intrinsic capacity in elderly patients with diabetes mellitus complicated by chronic kidney disease.Fasting blood glucose,2-hour postprandial blood glucose,glomerular filtration rate,6-minute walk distance,and scores in five dimensions of intrinsic capacity(exercise,cognition,psychology,vitality,and sensation)were measured before the intervention,at 4 weeks of intervention,and at 12 weeks of intervention for both groups.Results:Before the exercise intervention,there were no statistically significant differences(p>0.05)between the two groups in terms of fasting blood glucose,2-hour postprandial blood glucose,glomerular filtration rate,6-minute walk distance,and scores across five dimensions of intrinsic capacity:mobility,cognition,psychology,vitality,and sensation.After 12 weeks of intervention,the experimental group demonstrated significantly higher scores than the control group in glomerular filtration rate,6-minute walk distance,and the dimensions of mobility,cognition,and vitality within intrinsic capacity,with all differences being statistically significant(p<0.05).Conversely,the experimental group showed significantly lower scores than the control group in fasting blood glucose,2-hour postprandial blood glucose,and the psychological dimension of intrinsic capacity,with these differences also being statistically significant(p<0.05).Conclusion:Continuous nursing care utilizing telemedicine based on a hospital-community-family model combined with exercise intervention can effectively enhance exercise tolerance and intrinsic capacity in elderly patients with diabetes mellitus complicated by chronic kidney disease,thereby improving their quality of life.The effectiveness of the intervention is positively correlated with the duration of the intervention.
基金supported by the High-end Foreign Expert Introduction Program(Grant No.G2022165004L)the Sichuan Transportation Science and Technology Project(Grant No.2018-ZL-01)China Railway 20th Bureau Science and Technology Project(Grant No.YF1900SD07B).
文摘Root-inspired anchorage systems in the field of bio-inspired geotechnics are renowned for enhancing the pullout capacity of traditional geotechnical anchorage systems by simulating the morphology and architecture of plant root systems.However,limited studies have explored their practical applications,particularly in improving slope stability.To fill this gap,this study investigates the reinforcement effect of root-inspired anchors on slope stabilization using transparent soil modeling and 3D-printed anchors,and examines the impact of anchor branching patterns(i.e.branching numbers,branching angle,and branching nodes)on slope bearing capacity,shear band evolution,and temporal and spatial variation of slope deformation.The results show that peak slope bearing capacity increases with branching numbers and branching angles,correlating with the envelope area of the curved shear band.Upper anchors result in step-like deflections in the shear band near the trailing edge,while lower anchors convert the upward concave shear band into an upward convex one,thus increasing the slope bearing capacity.Slope deformation is minimized with intermediate branching parameters,such as a branching number of 4 and a branching angle of 45°.The anchor reinforcement mechanisms,i.e.anchor rod shear resistance,interface friction,anchor pullout capacity,and plate tightening effects,are comprehensively discussed,and the installation effects resulting from compromise slope modeling are identified as the contributors.These findings shed light on the failure process of root-inspired anchors reinforced slopes and provide a preliminary reference for potential applications,especially for the tradeoff between anchor branching,slope deformation,and slope stability.
基金supported by the National Key R&D Program of China(No.2023YFB3809500)the Fundamental Research Funds for the Central Universities(No.2024CDJXY003)+1 种基金the Venture&Innovation Support Program for Chongqing Overseas Returnees(cx2023087)The Chongqing Technology Innovation and Application Development Project(No.2024TIAD-KPX0003).
文摘Micro-sized anatase TiO_(2) displays inferior capacity as cathode material for magnesium ion batteries because of the higher diffusion energy barrier of Mg^(2+)in anatase TiO_(2) lattice.Herein,we report that nanosized anatase TiO_(2) exposed(001)facet doubles the capacity compared to the micro-sized sample ascribed to the interfacial Mg^(2+)ion storage.First-principles calculations reveal that the diffusion energy barrier of Mg^(2+)on the(001)facet is significantly lower than those in the bulk phase and on(100)facet,and the adsorption energy of Mg^(2+)on the(001)facet is also considerably lower than that on(100)facet,which guarantees superior interfacial Mg^(2+)storage of(001)facet.Moreover,anatase TiO_(2) exposed(001)facet displays a significantly higher capacity of 312.9 mAh g^(−1) in Mg-Li dual-salt electrolyte compared to 234.3 mAh g^(−1) in Li salt electrolyte.The adsorption energies of Mg^(2+)on(001)facet are much lower than the adsorption energies of Li+on(001)facet,implying that the Mg^(2+)ion interfacial storage is more favorable.These results highlight that controlling the crystal facet of the nanocrystals effectively enhances the interfacial storage of multivalent ions.This work offers valuable guidance for the rational design of high-capacity storage systems.
基金supported by the National Natural Science Foundation of China(Grant No.11571181)by the Natural Science Foundation of Jiangsu Province(Grant No.BK20171454).
文摘In this paper,we propose and analyze two second-order accurate finite difference schemes for the one-dimensional heat equation with concentrated capacity on a computa-tional domain=[a,b].We first transform the target equation into the standard heat equation on the domain excluding the singular point equipped with an inner interface matching(IIM)condition on the singular point x=ξ∈(a,b),then adopt Taylor’s ex-pansion to approximate the IIM condition at the singular point and apply second-order finite difference method to approximate the standard heat equation at the nonsingular points.This discrete procedure allows us to choose different grid sizes to partition the two sub-domains[a,ξ]and[ξ,b],which ensures that x=ξ is a grid point,and hence the pro-posed schemes can be generalized to the heat equation with more than one concentrated capacities.We prove that the two proposed schemes are uniquely solvable.And through in-depth analysis of the local truncation errors,we rigorously prove that the two schemes are second-order accurate both in temporal and spatial directions in the maximum norm without any constraint on the grid ratio.Numerical experiments are carried out to verify our theoretical conclusions.
基金financial support from National Natural Science Foundation of China(22032006,52075522,52322506)Strategic Priority Research Program of the Chinese Academy of Sciences(XDB 0470201)+3 种基金Outstanding Youth Fund of Gansu Province(21JR7RA095)Key Research Project of Shandong Provincial Natural Science Foundation(ZR2021ZD27)Gansu Province Basic Research Innovation Group Project(22JR5RA093)West Light Foundation of The Chinese Academy of Sciences(xbzg-zdsys-202211).
文摘Cartilage is well lubricated over a lifetime and this phenomenon is attributed to both of the surface hydration lubrication and the matrix load-bearing capacity.Lubricious hydrogels with a layered structure are designed to mimic cartilage as potential replacements.While many studies have concentrated on improving surface hydration to reduce friction,few have experimentally detected the relationship between load-bearing capacity of hydrogels and their interface friction behavior.In this work,a bilayer hydrogel,serving as a cartilage prototype consisted of a top thick hydrated polymer brush layer and a bottom hydrogel matrix with tunable modulus was designed to investigate this relationship.The coefficient of friction(COF,μ)is defined as the sum of interfacial component(μInt)and deformation/hysteresis component(μHyst).The presence of the top hydration layer effectively dissipates contact stress and reduces the interface interaction(μInt),leading to a stable and low COF.The contribution of mechanical deformation(μHyst)during the sliding shearing process to COF can be significantly reduced by increasing the local mechanical modulus,thereby enhancing the load-bearing capacity.These results show that the strategy of coupling surface hydration layer with a high load-bearing matrix can indeed enhance the lubrication performance of hydrogel cartilage prototypes,and implies a promising routine for designing robust soft matter lubrication system and friction-control devices.
文摘Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships with antioxidant activity and oxidative stability,gas chromatography-mass spectrometry was performed to characterize the associated fatty acid profiles.The antioxidant activity of vegetable oils,based on their DPPH-scavenging capacity(expressed as IC_(50) values),was used to assess their impact on human health,and their oxidative stability was characterized by performing lipid oxidation analysis to determine the oxidative induction time of fats and oils.In addition,correlation analyses were performed to examine associations between the fatty acid composition of the oils and DPPH-scavenging capacity and oxidative stability.The results revealed that among the assessed oils,coffee seed oil has the highest saturated fatty acid content(355.10 mg/g),whereas Garddenia jaminoides oil has the highest unsaturated fatty acid content(844.84 mg/g).Coffee seed oil was also found have the lowest DPPH IC_(50) value(2.30 mg/mL)and the longest oxidation induction time(17.09 h).Correlation analysis revealed a significant linear relationship(P<0.05)between oxidative stability and unsaturated fatty acid content,with lower contents tending to be associated with better oxidative stability.The findings of this study provide reference data for the screening of functional edible vegetable oils.
