The current research on the manufacturing of large-scale and complex components focuses mainly on the casting processes.Compared with casting,plastic forming has significant advantages in terms of performance.However,...The current research on the manufacturing of large-scale and complex components focuses mainly on the casting processes.Compared with casting,plastic forming has significant advantages in terms of performance.However,effectively controlling the material flow to achieve a reduced loading force and near-uniformity in the isothermal plastic forming process of large-scale asymmetric magnesium alloy complex housings(LSMACHs)is challenging.This study proposes a material flow control method based on the diffluence upsetting-extrusion forming(DUEF)process by dividing different forging deformation regions,combining these with the principal stress method,and establishing an efficient and accurate design procedure.A rational preformed billet was designed successfully using this method.Subsequently,a finite element simulation was employed to analyze the multiphysics fields of the DUEF process.The results indicated that compared with the traditional closed-die forging(TCDF)process,the DUEF process could control the orderly flow of materials,achieve short-distance filling of materials,and reduce hydrostatic stress.Simultaneously,it improved the deformation uniformity by 20.3%and reduced the loading force by 22.6%.Finally,the rationality of the proposed method was validated through physical experiments.Compared with the TCDF process,the DUEF process exhibited a low loading force and uniform mechanical properties.The proposed material flow control method based on the DUEF process provides a new technological approach for the plastic formation of LSMACH and similar components.展开更多
In order to achieve higher efficient cohesion match of procedure and equipment between ironmaking and steelmaking interface, the theory of multi-dimensional material flow control was applied to analyze torpedo ladle-i...In order to achieve higher efficient cohesion match of procedure and equipment between ironmaking and steelmaking interface, the theory of multi-dimensional material flow control was applied to analyze torpedo ladle-iron ladle transportation process between blast furnace and basic oxygen furnace. Moreover, basic parameters of material flow were analyzed and optimized, such as time, temperature and material quantity. Based on operating principles of material flow, control methods were optimized, such as product organization mode, scheduling discipline and scheduling plan of hot metal ladle. Finally, the material flow control technology of ironmaking and steelmaking interface was integrated. Satisfactory effects are obtained after applying the technology in practice. The total turnover number of torpedo ladle decreases from 20 to 18, the hot metal temperature of 1# BF torpedo ladle decreases from 36 °C to 19.5 °C, the hot metal temperature of 2# BF torpedo ladle decreases from 36.6 °C to 19.8 °C, the temperature drop of desulfurization hot metal decreases by 4 °C, and the temperature drop of non-desulfurization hot metal decreases by 2.8 °C. Furthermore, the ironmaking and steelmaking interface system will realize high-efficiency control by using this control technology.展开更多
This research evaluated the use of sewage sludge and refuse incineration bottom ash to replace calcium sulfoaluminate cement （CSA） in making controlled low-strength material （CLSM）. Various properties of CLSM mixt...This research evaluated the use of sewage sludge and refuse incineration bottom ash to replace calcium sulfoaluminate cement （CSA） in making controlled low-strength material （CLSM）. Various properties of CLSM mixtures were characterized in terms of unconfined compressive strength, microstructure and leachability. It was found that the strength of tested CLSM mixtures ranged from 3.6 to 9.0 MPa, over the upper excavatable limit of 2.1 MPa. The micro-structural analysis revealed that sewage sludge and bottom ash were crystallochemically in- corporated within CLSM system_s by forming the needle-like ettringite （C3A＇3CS＇_H32） with exiguous tu.bers via the typical Pozzolanic Reaction, leading to a dense and low-porosity microst;＇ucture. Furthermore,-the toxicity characteristic leaching procedure evidenced that the cumulative leachable metals in the leachate were much below the regulatory thresholds. The potential for us!ng sewage sludge and bottom ash!n CLSM makin.g was thus confirmed.展开更多
Sixteen controlled low-strength material( CLSM)mixtures with various cement-to-sand( C/Sa) ratios and water-to-solid( W/So) ratios were prepared using recycled fine aggregate from urban red brick based construction wa...Sixteen controlled low-strength material( CLSM)mixtures with various cement-to-sand( C/Sa) ratios and water-to-solid( W/So) ratios were prepared using recycled fine aggregate from urban red brick based construction waste.The fluidity and bleeding of the fresh CLSM mixtures were measured via the modified test methods, and the hardened CLSM mixtures were then molded to evaluate their compressive strength and durability. The results showthat the fluidity of the fresh CLSM mixtures is 105 to 227 mm with the corresponding bleeding rate of 3. 7% to 15. 5%, which increases with the increase in fluidity. After aging for 28 d,the compressive strength of the hardened CLSM mixtures reaches 1. 15 to 13. 96 M Pa, and their strength can be further enhanced with longer curing ages. Additionally, the strength increases with the increase of the C/Sa ratio, and decreases with the increase of the W/So ratio under the same curing age. Based on the obtained compressive strength, a fitting model for accurately predicting the compressive strength of the CLSM mixtures was established, which takes into account the above two independent variables( C/Sa and W/So ratios).M oreover, the durability of the hardened CLSM mixtures is enhanced for samples with higher C/Sa ratios.展开更多
The paper discusses how the inventory control of army equipment material runs sytematically under the two-level maintenance system,and establishes the inventory control model based on system dynamics.On the basis of m...The paper discusses how the inventory control of army equipment material runs sytematically under the two-level maintenance system,and establishes the inventory control model based on system dynamics.On the basis of modeling and simulation,the influence of different inventory upper limit on the whole system is studied,and the optimal inventory control mechanism under the model condition is foud.In addition,through the simulation of two replenishment strategies(s,S) and(T,s,S),the advantages and disadvantages and feasibility of each replenishment strategy are analyzed.展开更多
At the present stage, the competitive environment among enterprises in our social market is increasingly fierce, which requires strong practical ability and innovation ability for talents. Experimental teaching, as th...At the present stage, the competitive environment among enterprises in our social market is increasingly fierce, which requires strong practical ability and innovation ability for talents. Experimental teaching, as the main means to cultivate talents' problem-solving ability, practical ability and creative ability, should be reformed and innovated in time so as to improve the efficiency and quality of experimental teaching for material forming and control engineering major. Based on this, this paper mainly analyzes the importance of experimental teaching of material forming and control engineering in colleges and universities, and puts forward some methods of exploration and construction of experimental teaching for reference.展开更多
Degradation of nitrobenzene(NB)via Fenton-like reaction is considered as an efficient approach for contaminated groundwater remediation.However,the poor stability of H2O2limits the application of traditional Fenton re...Degradation of nitrobenzene(NB)via Fenton-like reaction is considered as an efficient approach for contaminated groundwater remediation.However,the poor stability of H2O2limits the application of traditional Fenton reactions in soil and groundwater due to the transportation risks of H_(2)O_(2).In this study,we synthesized a controlled release nano calcium peroxide(n CP)by coating it with polydopamine(PDA)as a solid H2O2to construct a Fe(Ⅱ)/PDA@n CP Fenton-like system for contaminants degradation.The phenolquinone transformations of catechol groups on the PDA surface facilitated the Fe(Ⅱ)/Fe(Ⅲ)cycle,resulting in enhanced generation of hydroxyl radicals(HO·)and effective long-term degradation of NB.Moreover,the PDA shell modulated the n CP decomposition rate and inhibited sharp p H fluctuations,and the NB removal efficiency was achieved up to 96.8%at p H ranging from 3.0 to 9.0.This study demonstrated the promising application potential of PDA@n CP as a solid-controlled release H2O2source in Fenton-like system for groundwater contamination remediation.展开更多
The piezoelectric materials are used to investigate the active vibration control of ordered/disordered periodic two-span beams. The equation of motion of each sub-beam with piezoelectric patches is established based o...The piezoelectric materials are used to investigate the active vibration control of ordered/disordered periodic two-span beams. The equation of motion of each sub-beam with piezoelectric patches is established based on Hamilton＇s principle with an assumed mode method. The velocity feedback control algorithm is used to design the controller. The free and forced vibration behaviors of the two-span beams with the piezoelectric actuators and sensors are analyzed. The vibration properties of the disordered two-span beams caused by misplacing the middle support are also researched. In addition, the effects of the length disorder degree on the vibration performances of the disordered beams are investigated. From the numerical results, it can be concluded that the disorder in the length of the periodic two-span beams will cause vibration localizations of the free and forced vibrations of the structure, and the vibration localization phenomenon will be more and more obvious when the length difference between the two sub-beams increases. Moreover, when the velocity feedback control is used, both the forced and the free vibrations will be suppressed. Meanwhile, the vibration behaviors of the two-span beam are tuned.展开更多
Focused on the lost circulation control in deep naturally fractured reservoirs, the multiscale structure of fracture plugging zone is proposed based on the theory of granular matter mechanics, and the structural failu...Focused on the lost circulation control in deep naturally fractured reservoirs, the multiscale structure of fracture plugging zone is proposed based on the theory of granular matter mechanics, and the structural failure pattern of plugging zone is developed to reveal the plugging zone failure mechanisms in deep, high temperature, high pressure, and high in-situ stress environment. Based on the fracture plugging zone strength model, key performance parameters are determined for the optimal selection of loss control material(LCM). Laboratory fracture plugging experiments with new LCM are carried out to evaluate the effect of the key performance parameters of LCM on fracture plugging quality. LCM selection strategy for fractured reservoirs is developed. The results show that the force chain formed by LCMs determines the pressure stabilization of macro-scale fracture plugging zone. Friction failure and shear failure are the two major failure patterns of fracture plugging zone. The strength of force chain depends on the performance of micro-scale LCM, and the LCM key performance parameters include particle size distribution, fiber aspect ratio, friction coefficient, compressive strength, soluble ability and high temperature resistance. Results of lab experiments and field test show that lost circulation control quality can be effectively improved with the optimal material selection based on the extracted key performance parameters of LCMs.展开更多
Lung diseases associated with alveoli,such as acute respiratory distress syndrome,have posed a long-term threat to human health.However,an in vitro model capable of simulating different deformations of the alveoli and...Lung diseases associated with alveoli,such as acute respiratory distress syndrome,have posed a long-term threat to human health.However,an in vitro model capable of simulating different deformations of the alveoli and a suitable material for mimicking basement membrane are currently lacking.Here,we present an innovative biomimetic controllable strain membrane(BCSM)at an air–liquid interface(ALI)to reconstruct alveolar respiration.The BCSM consists of a high-precision three-dimensional printing melt-electrowritten polycaprolactone(PCL)mesh,coated with a hydrogel substrate—to simulate the important functions(such as stiffness,porosity,wettability,and ALI)of alveolar microenvironments,and seeded pulmonary epithelial cells and vascular endothelial cells on either side,respectively.Inspired by papercutting,the BCSM was fabricated in the plane while it operated in three dimensions.A series of the topological structure of the BCSM was designed to control various local-area strain,mimicking alveolar varied deformation.Lopinavir/ritonavir could reduce Lamin A expression under over-stretch condition,which might be effective in preventing ventilator-induced lung injury.The biomimetic lung-unit model with BCSM has broader application prospects in alveoli-related research in the future,such as in drug toxicology and metabolism.展开更多
Triboelectric nanogenerators(TENG),renowned for their remarkable capability to harness weak mechanical energy from the environment,have gained considerable attention owing to their cost-effectiveness,high output,and a...Triboelectric nanogenerators(TENG),renowned for their remarkable capability to harness weak mechanical energy from the environment,have gained considerable attention owing to their cost-effectiveness,high output,and adaptability.This review provides a unique perspective by conducting a comprehensive and in-depth analysis of magnetically assisted TENGs that encompass structures,materials,and self-powered sensing systems.We systematically summarize the diverse functions of the magnetic assistance for TENGs,including system stiffness,components of the hybrid electromagnetic-triboelectric generator,transmission,and interaction forces.In the material domain,we review the incorporation of magnetic nano-composites materials,along with ferrofluid-based TENG and microstructure verification,which have also been summarized based on existing research.Furthermore,we delve into the research progress on physical quantity sensing and human-machine interface in magnetic-assisted TENGs.Our analysis highlights that magnetic assistance extends beyond the repulsive and suction forces under a magnetic field,thereby playing multifaceted roles in improving the output performance and environmental adaptability of the TENGs.Finally,we present the prevailing challenges and offer insights into the future trajectory of the magnetic-assisted TENGs development.展开更多
This paper explores the latest breakthroughs in the controllable water transport of textile porous materials,presenting a comprehensive overview of the mechanism that governs water transport in textile porous material...This paper explores the latest breakthroughs in the controllable water transport of textile porous materials,presenting a comprehensive overview of the mechanism that governs water transport in textile porous materials.The mechanism is determined by several factors including porosity,pore size distributions,capillary diameter gradients,cross-section and angle gradients of capillaries,and contact angle and surface tension gradients.Four methods to achieve controllable water transport properties in textiles are elaborated:structural design,chemical finishing,plasma treatment,and ultraviolet photocatalysis.Moreover,three distinct applications of controllable water transport in textile porous materials are revealed,including oil-water separation,fog/water harvesting,and functional/intelligent textiles.The potential environmental benefits and advancements in textile controllable water transport properties are also highlighted.The review concludes by suggesting promising research works in the future.展开更多
Global warming and the increasing frequency of extreme weather events pose serious threats to natural ecosystems and human well-being,creating an urgent need for energy-efficient cooling technologies.Conventional cool...Global warming and the increasing frequency of extreme weather events pose serious threats to natural ecosystems and human well-being,creating an urgent need for energy-efficient cooling technologies.Conventional cooling approaches,such as vapor compression systems and cooling units,account for approximately 15%of global electricity consumption,with energy demand continuing to rise annually[1].Consequently,the development of advanced cooling technologies that reduce both energy usage and environmental impact has become a pressing priority.展开更多
A coupled CFD-DEM method is used to simulate the formation process of fracture plugging zone.A photo-elastic system characterizing mesoscale force chain network developed by our own is used to model the pressure evolu...A coupled CFD-DEM method is used to simulate the formation process of fracture plugging zone.A photo-elastic system characterizing mesoscale force chain network developed by our own is used to model the pressure evolution in fracture plugging zone to reveal the evolution mechanism of the structure of fracture plugging zone.A theoretical basis is provided for improving the lost circulation control effect in fractured reservoirs and novel methods are proposed for selecting loss control materials and designing loss control formula.CFD-DEM simulation results show that bridging probability is the key factor determining the formation of fracture plugging zone and fracture plugging efficiency.Critical and absolute bridging concentrations are proposed as the key indexes for loss control formula design.With the increase of absolute bridging concentration,the governing factor of bridging is changed from material grain size to the combination of material grain size and friction force.Results of photo-elastic experiments show that mesoscale force chain network is the intrinsic factor affecting the evolution of pressure exerting on the fracture plugging zone and determines the macroscopic strength of fracture plugging zone.Performance parameters of loss control material affect the force chain network structure and the ratio of stronger force chain,and further impact the stability and strength of fracture plugging zone.Based on the study results,the loss control formula is optimized and new-type loss control material is designed.Laboratory experiments results show that the fracture plugging efficiency and strength is effectively improved.展开更多
Phar.Eur.Herbal Drug(HD)monographs state which aspects have to be considered for quality assurance through the relevant chapters'Definition'.'Characters','Identification','Tests',and...Phar.Eur.Herbal Drug(HD)monographs state which aspects have to be considered for quality assurance through the relevant chapters'Definition'.'Characters','Identification','Tests',and'Assay'.Identification of botanical material is achieved by macroscopic and microscopic morphology,generally examined by a trained expert.Content or assay is the most difficult area of展开更多
Leakage control in deep oil and gas wells is challenging,often leading to increased costs.In this study,a low-density,high-pressure resistant and thermally stable epoxy resin(BEPD)was synthesized by ring opening of 2,...Leakage control in deep oil and gas wells is challenging,often leading to increased costs.In this study,a low-density,high-pressure resistant and thermally stable epoxy resin(BEPD)was synthesized by ring opening of 2,2-bis(4-epoxypropoxyphenyl)propane cured with 1,8-diaminonaphthalene.The material was thoroughly characterized using fourier-transform infrared spectroscopy,a universal testing machine,thermogravimetric analysis,and density testing.Comprehensive experimental and simulation analyses were conducted to evaluate BEPD's dispersion stability,its impact on the rheological properties of drilling fluid,and its effectiveness as a leakage control agent.It exhibits a high compressive strength(250.12 MPa)and a thermal decomposition temperature of 337.75℃,making it suitable for high-temperature environments.Its irregular particle shape ensures a strong bond with surrounding strata,forming a stable plugging layer.With a density of 1.09 g/cm^(3),BEPD disperses well in plugging slurry,reducing sedimentation.At dosages between 1%and 4%,it doesn't significantly affect the rheology of the slurry and effectively prevents sedimentation.BEPD particles effectively plugged fractures ranging from 1 to 4 mm,withstanding pressures up to 11.5 MPa.This performance is due to its unique particle size distribution,where larger particles act as bridges and smaller particles fill gaps,forming a dense plugging layer.BEPD shows potential as a highly effective material for improving leakage control in deep well applications.展开更多
T-cell acute lymphoblastic leukemia(T-ALL)is a common yet severe pediatric cancer treated with Lasparaginase(ASP).To boost the treatment's effectiveness and lessen its toxicity,enzyme@MOF nanoparticles were engine...T-cell acute lymphoblastic leukemia(T-ALL)is a common yet severe pediatric cancer treated with Lasparaginase(ASP).To boost the treatment's effectiveness and lessen its toxicity,enzyme@MOF nanoparticles were engineered with a hyaluronic acid(HA)-targeted polyethylene glycol(PEG)surface.These nanoparticles,termed ASP@MOF/PEG-HA,showed efficient uptake by drug-resistant T-ALL cells.The p Hsensitive zeolitic imidazolate framework-8(ZIF-8)based metal-organic framework(MOF)nanoparticles allowed the encapsulated ASP to significantly increase cytotoxicity against T-ALL cells.Furthermore,HA's ability to bind to T-ALL cells with elevated CD44 expression further induced apoptosis in CD44^(+) T-ALL cells with poor prognosis.In animal models,the nanoparticles improved survival rates and reduced the burden of leukemia,demonstrating substantial anti-leukemia effects.Thus,these nanoparticles offer an effective treatment approach for drug-resistant T-ALL cells characterized by increased CD44 expression.展开更多
Introduction:Emerging and re-emerging transfusion-transmitted arboviruses remain a persistent public health challenge to global blood safety.This study aims to establish a comprehensive nucleic acid testing(NAT)qualit...Introduction:Emerging and re-emerging transfusion-transmitted arboviruses remain a persistent public health challenge to global blood safety.This study aims to establish a comprehensive nucleic acid testing(NAT)quality control system for Dengue virus(DENV),Zika virus(ZIKV),and Chikungunya virus(CHIKV)screening in blood donations to evaluate the performance of domestic screening reagents,and to assess the prevalence of these arboviruses in border regions.Methods:Pseudovirus quality control materials based on the Moloney murine leukemia virus(MMLV)vector was constructed to evaluate the limit of detection(LoD)and precision of six blood screening reagents.An external quality assessment(EQA)was conducted across eight central blood stations in Guangxi Zhuang Aotonomous Region and Yunnan Provinces.These blood stations employed either reagent A or E for DENV/ZIKV/CHIKV triplex-assay screening of blood donor samples collected during epidemic seasons(June–August)in 2022 and 2023.Results:The six reagents exhibited varied LoD.All evaluated reagents exhibited excellent precision with coefficient of variation(CV)values<5%.All eight central blood stations achieved EQA scores above 80.In 2022,a total of 45,383 blood samples were screened,with no positive cases detected.In 2023,44,972 blood donors were screened,and nine samples tested positive at the Xishuangbanna central blood station.Confirmatory testing verified six Dengue virus serotype 1(DENV-1)infections among these cases.Conclusions:This study successfully established a robust quality assurance system for NAT-based arbovirus screening in China.The detection of DENV-positive samples underscore the persisting risk of transfusion-transmitted infections in endemic regions.Continued surveillance and enhanced screening strategies are essential to safeguard blood safety,particularly in arboviral hotspot regions with tropical/subtropical climates prone to recurrent outbreaks.展开更多
Covalent organic frameworks (COFs) are well known as the next generation of shape-persistent zeolite analogues, which have brought new impetus to the development of porous organic materials as well as two-dimensional ...Covalent organic frameworks (COFs) are well known as the next generation of shape-persistent zeolite analogues, which have brought new impetus to the development of porous organic materials as well as two-dimensional polymers. Since the advent of COFs in 2005, many striking findings have definitely proven their great potentials expanding applications across energy,environment and healthcare fields. With thorough exploration over a decade, research interest has been drawn on the scientific challenges on chemistry, while making full play of COF values has remained far from satisfactory yet. Thus opening an avenue to modulating COF assemblies on the multi-scale is no longer just an option, but a necessity for matching the application requirements with enhanced performances. In this mini-review, we summarize the recent progress on design of nanoscale COFs with varying forms. Detailed description is concentrated on the synthetic strategies of COF assemblies such as spheres, fibers,tubes, coatings and films, thereby shedding light on the flexible manipulation over dimensions, compositions and morphologies.Meanwhile, the advanced applications of nanoscale COFs have been discussed here with comparison of their bulky counterparts.展开更多
基金Supported by National Natural Science Foundation of China(Grant No.52075501).
文摘The current research on the manufacturing of large-scale and complex components focuses mainly on the casting processes.Compared with casting,plastic forming has significant advantages in terms of performance.However,effectively controlling the material flow to achieve a reduced loading force and near-uniformity in the isothermal plastic forming process of large-scale asymmetric magnesium alloy complex housings(LSMACHs)is challenging.This study proposes a material flow control method based on the diffluence upsetting-extrusion forming(DUEF)process by dividing different forging deformation regions,combining these with the principal stress method,and establishing an efficient and accurate design procedure.A rational preformed billet was designed successfully using this method.Subsequently,a finite element simulation was employed to analyze the multiphysics fields of the DUEF process.The results indicated that compared with the traditional closed-die forging(TCDF)process,the DUEF process could control the orderly flow of materials,achieve short-distance filling of materials,and reduce hydrostatic stress.Simultaneously,it improved the deformation uniformity by 20.3%and reduced the loading force by 22.6%.Finally,the rationality of the proposed method was validated through physical experiments.Compared with the TCDF process,the DUEF process exhibited a low loading force and uniform mechanical properties.The proposed material flow control method based on the DUEF process provides a new technological approach for the plastic formation of LSMACH and similar components.
基金Project(2011FZ056)supported by the Applied Basic Research Plan Program of Yunnan Province,China
文摘In order to achieve higher efficient cohesion match of procedure and equipment between ironmaking and steelmaking interface, the theory of multi-dimensional material flow control was applied to analyze torpedo ladle-iron ladle transportation process between blast furnace and basic oxygen furnace. Moreover, basic parameters of material flow were analyzed and optimized, such as time, temperature and material quantity. Based on operating principles of material flow, control methods were optimized, such as product organization mode, scheduling discipline and scheduling plan of hot metal ladle. Finally, the material flow control technology of ironmaking and steelmaking interface was integrated. Satisfactory effects are obtained after applying the technology in practice. The total turnover number of torpedo ladle decreases from 20 to 18, the hot metal temperature of 1# BF torpedo ladle decreases from 36 °C to 19.5 °C, the hot metal temperature of 2# BF torpedo ladle decreases from 36.6 °C to 19.8 °C, the temperature drop of desulfurization hot metal decreases by 4 °C, and the temperature drop of non-desulfurization hot metal decreases by 2.8 °C. Furthermore, the ironmaking and steelmaking interface system will realize high-efficiency control by using this control technology.
基金Supported by the Science and Technology Commission of Shanghai Municipality (08 DZ 1202802,09 DZ 1204105,09 DZ2251700)the National Natural Science Foundation of China (51008322)
文摘This research evaluated the use of sewage sludge and refuse incineration bottom ash to replace calcium sulfoaluminate cement （CSA） in making controlled low-strength material （CLSM）. Various properties of CLSM mixtures were characterized in terms of unconfined compressive strength, microstructure and leachability. It was found that the strength of tested CLSM mixtures ranged from 3.6 to 9.0 MPa, over the upper excavatable limit of 2.1 MPa. The micro-structural analysis revealed that sewage sludge and bottom ash were crystallochemically in- corporated within CLSM system_s by forming the needle-like ettringite （C3A＇3CS＇_H32） with exiguous tu.bers via the typical Pozzolanic Reaction, leading to a dense and low-porosity microst;＇ucture. Furthermore,-the toxicity characteristic leaching procedure evidenced that the cumulative leachable metals in the leachate were much below the regulatory thresholds. The potential for us!ng sewage sludge and bottom ash!n CLSM makin.g was thus confirmed.
基金The National Science and Technology Support Program of China(No.2014BAC07B03)the Science and Technology Project of Transportation Committee of Beijing Government(No.2016-LZJKJ-01-006)the National Natural Science Foundation of China(No.51278016)
文摘Sixteen controlled low-strength material( CLSM)mixtures with various cement-to-sand( C/Sa) ratios and water-to-solid( W/So) ratios were prepared using recycled fine aggregate from urban red brick based construction waste.The fluidity and bleeding of the fresh CLSM mixtures were measured via the modified test methods, and the hardened CLSM mixtures were then molded to evaluate their compressive strength and durability. The results showthat the fluidity of the fresh CLSM mixtures is 105 to 227 mm with the corresponding bleeding rate of 3. 7% to 15. 5%, which increases with the increase in fluidity. After aging for 28 d,the compressive strength of the hardened CLSM mixtures reaches 1. 15 to 13. 96 M Pa, and their strength can be further enhanced with longer curing ages. Additionally, the strength increases with the increase of the C/Sa ratio, and decreases with the increase of the W/So ratio under the same curing age. Based on the obtained compressive strength, a fitting model for accurately predicting the compressive strength of the CLSM mixtures was established, which takes into account the above two independent variables( C/Sa and W/So ratios).M oreover, the durability of the hardened CLSM mixtures is enhanced for samples with higher C/Sa ratios.
文摘The paper discusses how the inventory control of army equipment material runs sytematically under the two-level maintenance system,and establishes the inventory control model based on system dynamics.On the basis of modeling and simulation,the influence of different inventory upper limit on the whole system is studied,and the optimal inventory control mechanism under the model condition is foud.In addition,through the simulation of two replenishment strategies(s,S) and(T,s,S),the advantages and disadvantages and feasibility of each replenishment strategy are analyzed.
文摘At the present stage, the competitive environment among enterprises in our social market is increasingly fierce, which requires strong practical ability and innovation ability for talents. Experimental teaching, as the main means to cultivate talents' problem-solving ability, practical ability and creative ability, should be reformed and innovated in time so as to improve the efficiency and quality of experimental teaching for material forming and control engineering major. Based on this, this paper mainly analyzes the importance of experimental teaching of material forming and control engineering in colleges and universities, and puts forward some methods of exploration and construction of experimental teaching for reference.
基金supported by the National Natural Science Foundation of China(Nos.42077185,U22A20591)the Sichuan Science and Technology Program for Distinguished Young Scholars(Nos.2022JDJQ0010,2022ZYD0040)+1 种基金the National Key Research and Development Program of China(No.2020YFC1808300)the Research Fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(No.SKLGP2020Z002)。
文摘Degradation of nitrobenzene(NB)via Fenton-like reaction is considered as an efficient approach for contaminated groundwater remediation.However,the poor stability of H2O2limits the application of traditional Fenton reactions in soil and groundwater due to the transportation risks of H_(2)O_(2).In this study,we synthesized a controlled release nano calcium peroxide(n CP)by coating it with polydopamine(PDA)as a solid H2O2to construct a Fe(Ⅱ)/PDA@n CP Fenton-like system for contaminants degradation.The phenolquinone transformations of catechol groups on the PDA surface facilitated the Fe(Ⅱ)/Fe(Ⅲ)cycle,resulting in enhanced generation of hydroxyl radicals(HO·)and effective long-term degradation of NB.Moreover,the PDA shell modulated the n CP decomposition rate and inhibited sharp p H fluctuations,and the NB removal efficiency was achieved up to 96.8%at p H ranging from 3.0 to 9.0.This study demonstrated the promising application potential of PDA@n CP as a solid-controlled release H2O2source in Fenton-like system for groundwater contamination remediation.
基金Project supported by the National Basic Research Program of China(973 Program)(No.2011CB711100)the National Natural Science Foundation of China(Nos.10672017 and11172084)
文摘The piezoelectric materials are used to investigate the active vibration control of ordered/disordered periodic two-span beams. The equation of motion of each sub-beam with piezoelectric patches is established based on Hamilton＇s principle with an assumed mode method. The velocity feedback control algorithm is used to design the controller. The free and forced vibration behaviors of the two-span beams with the piezoelectric actuators and sensors are analyzed. The vibration properties of the disordered two-span beams caused by misplacing the middle support are also researched. In addition, the effects of the length disorder degree on the vibration performances of the disordered beams are investigated. From the numerical results, it can be concluded that the disorder in the length of the periodic two-span beams will cause vibration localizations of the free and forced vibrations of the structure, and the vibration localization phenomenon will be more and more obvious when the length difference between the two sub-beams increases. Moreover, when the velocity feedback control is used, both the forced and the free vibrations will be suppressed. Meanwhile, the vibration behaviors of the two-span beam are tuned.
基金Supported by the National Natural Science Foundation of China(Grant No.51604236)Science and Technology Program of Sichuan Province(Grant No.2018JY0436)the Sichuan Province Youth Science and Technology Innovation Team Project(Grant No.2016TD0016)
文摘Focused on the lost circulation control in deep naturally fractured reservoirs, the multiscale structure of fracture plugging zone is proposed based on the theory of granular matter mechanics, and the structural failure pattern of plugging zone is developed to reveal the plugging zone failure mechanisms in deep, high temperature, high pressure, and high in-situ stress environment. Based on the fracture plugging zone strength model, key performance parameters are determined for the optimal selection of loss control material(LCM). Laboratory fracture plugging experiments with new LCM are carried out to evaluate the effect of the key performance parameters of LCM on fracture plugging quality. LCM selection strategy for fractured reservoirs is developed. The results show that the force chain formed by LCMs determines the pressure stabilization of macro-scale fracture plugging zone. Friction failure and shear failure are the two major failure patterns of fracture plugging zone. The strength of force chain depends on the performance of micro-scale LCM, and the LCM key performance parameters include particle size distribution, fiber aspect ratio, friction coefficient, compressive strength, soluble ability and high temperature resistance. Results of lab experiments and field test show that lost circulation control quality can be effectively improved with the optimal material selection based on the extracted key performance parameters of LCMs.
基金sponsored by the National Key Research and Development Program of China(2021YFC2501800)the National Natural Science Foundation of China(No.U1909218)the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(No.T2121004).
文摘Lung diseases associated with alveoli,such as acute respiratory distress syndrome,have posed a long-term threat to human health.However,an in vitro model capable of simulating different deformations of the alveoli and a suitable material for mimicking basement membrane are currently lacking.Here,we present an innovative biomimetic controllable strain membrane(BCSM)at an air–liquid interface(ALI)to reconstruct alveolar respiration.The BCSM consists of a high-precision three-dimensional printing melt-electrowritten polycaprolactone(PCL)mesh,coated with a hydrogel substrate—to simulate the important functions(such as stiffness,porosity,wettability,and ALI)of alveolar microenvironments,and seeded pulmonary epithelial cells and vascular endothelial cells on either side,respectively.Inspired by papercutting,the BCSM was fabricated in the plane while it operated in three dimensions.A series of the topological structure of the BCSM was designed to control various local-area strain,mimicking alveolar varied deformation.Lopinavir/ritonavir could reduce Lamin A expression under over-stretch condition,which might be effective in preventing ventilator-induced lung injury.The biomimetic lung-unit model with BCSM has broader application prospects in alveoli-related research in the future,such as in drug toxicology and metabolism.
基金supported by the General Program of the National Natural Science Foundation of China(NSFC,No.52075061)the Key Program of the National Natural Science Foundation of China(NSFC,No.U22B2089)the Science Fund for Distinguished Young Scholars of Chongqing(No.CSTB2022 NSCQ-JQX0006).
文摘Triboelectric nanogenerators(TENG),renowned for their remarkable capability to harness weak mechanical energy from the environment,have gained considerable attention owing to their cost-effectiveness,high output,and adaptability.This review provides a unique perspective by conducting a comprehensive and in-depth analysis of magnetically assisted TENGs that encompass structures,materials,and self-powered sensing systems.We systematically summarize the diverse functions of the magnetic assistance for TENGs,including system stiffness,components of the hybrid electromagnetic-triboelectric generator,transmission,and interaction forces.In the material domain,we review the incorporation of magnetic nano-composites materials,along with ferrofluid-based TENG and microstructure verification,which have also been summarized based on existing research.Furthermore,we delve into the research progress on physical quantity sensing and human-machine interface in magnetic-assisted TENGs.Our analysis highlights that magnetic assistance extends beyond the repulsive and suction forces under a magnetic field,thereby playing multifaceted roles in improving the output performance and environmental adaptability of the TENGs.Finally,we present the prevailing challenges and offer insights into the future trajectory of the magnetic-assisted TENGs development.
基金supported by the National Natural Science Foundation of China(No.12472141)Shaanxi Outstanding Youth Science Fund Project,China(No.2024JC-JCQN-03)Youth Innovation Team of Shaanxi Universities and Institute of Flexible Electronics and Intelligent Textile.
文摘This paper explores the latest breakthroughs in the controllable water transport of textile porous materials,presenting a comprehensive overview of the mechanism that governs water transport in textile porous materials.The mechanism is determined by several factors including porosity,pore size distributions,capillary diameter gradients,cross-section and angle gradients of capillaries,and contact angle and surface tension gradients.Four methods to achieve controllable water transport properties in textiles are elaborated:structural design,chemical finishing,plasma treatment,and ultraviolet photocatalysis.Moreover,three distinct applications of controllable water transport in textile porous materials are revealed,including oil-water separation,fog/water harvesting,and functional/intelligent textiles.The potential environmental benefits and advancements in textile controllable water transport properties are also highlighted.The review concludes by suggesting promising research works in the future.
基金supported by the China National Petroleum Corporation Innovation Fund(2024DQ02-0409)the National Key Research Program(2020YFC2201103 and 2020YFA0210702)the National Natural Science Foundation of China(220375163).
文摘Global warming and the increasing frequency of extreme weather events pose serious threats to natural ecosystems and human well-being,creating an urgent need for energy-efficient cooling technologies.Conventional cooling approaches,such as vapor compression systems and cooling units,account for approximately 15%of global electricity consumption,with energy demand continuing to rise annually[1].Consequently,the development of advanced cooling technologies that reduce both energy usage and environmental impact has become a pressing priority.
基金Supported by the National Natural Science Foundation of China(51604236)Open Fund of the State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation(PLN201913)+1 种基金Science and Technology Planning Project of the Sichuan Province,China(2018JY0436)Sichuan Youth Science and Technology Innovation Research Team Project for Unconventional Oil and Gas Reservoir Protection(2016TD0016)。
文摘A coupled CFD-DEM method is used to simulate the formation process of fracture plugging zone.A photo-elastic system characterizing mesoscale force chain network developed by our own is used to model the pressure evolution in fracture plugging zone to reveal the evolution mechanism of the structure of fracture plugging zone.A theoretical basis is provided for improving the lost circulation control effect in fractured reservoirs and novel methods are proposed for selecting loss control materials and designing loss control formula.CFD-DEM simulation results show that bridging probability is the key factor determining the formation of fracture plugging zone and fracture plugging efficiency.Critical and absolute bridging concentrations are proposed as the key indexes for loss control formula design.With the increase of absolute bridging concentration,the governing factor of bridging is changed from material grain size to the combination of material grain size and friction force.Results of photo-elastic experiments show that mesoscale force chain network is the intrinsic factor affecting the evolution of pressure exerting on the fracture plugging zone and determines the macroscopic strength of fracture plugging zone.Performance parameters of loss control material affect the force chain network structure and the ratio of stronger force chain,and further impact the stability and strength of fracture plugging zone.Based on the study results,the loss control formula is optimized and new-type loss control material is designed.Laboratory experiments results show that the fracture plugging efficiency and strength is effectively improved.
文摘Phar.Eur.Herbal Drug(HD)monographs state which aspects have to be considered for quality assurance through the relevant chapters'Definition'.'Characters','Identification','Tests',and'Assay'.Identification of botanical material is achieved by macroscopic and microscopic morphology,generally examined by a trained expert.Content or assay is the most difficult area of
基金supported by the Open Fund of State Key Laboratory Oil and Gas Reservoir Geology and Exploitation(Southwest Petroleum University)(No.PLN2022-22,PLN2022-32)Science and Technology Cooperation Project of the CNPC-SWPU Innovation Alliance(No.2020CX040102,2020CX040201)+1 种基金Special Projects of Central Government Guiding Development of Local Science and Technology,China(No.2023ZYD0033)Natural Science Foundation of Sichuan Province(No.2025ZNSFSC0377).
文摘Leakage control in deep oil and gas wells is challenging,often leading to increased costs.In this study,a low-density,high-pressure resistant and thermally stable epoxy resin(BEPD)was synthesized by ring opening of 2,2-bis(4-epoxypropoxyphenyl)propane cured with 1,8-diaminonaphthalene.The material was thoroughly characterized using fourier-transform infrared spectroscopy,a universal testing machine,thermogravimetric analysis,and density testing.Comprehensive experimental and simulation analyses were conducted to evaluate BEPD's dispersion stability,its impact on the rheological properties of drilling fluid,and its effectiveness as a leakage control agent.It exhibits a high compressive strength(250.12 MPa)and a thermal decomposition temperature of 337.75℃,making it suitable for high-temperature environments.Its irregular particle shape ensures a strong bond with surrounding strata,forming a stable plugging layer.With a density of 1.09 g/cm^(3),BEPD disperses well in plugging slurry,reducing sedimentation.At dosages between 1%and 4%,it doesn't significantly affect the rheology of the slurry and effectively prevents sedimentation.BEPD particles effectively plugged fractures ranging from 1 to 4 mm,withstanding pressures up to 11.5 MPa.This performance is due to its unique particle size distribution,where larger particles act as bridges and smaller particles fill gaps,forming a dense plugging layer.BEPD shows potential as a highly effective material for improving leakage control in deep well applications.
基金supported by the National Natural Science Foundation of China(Nos.52203206,52173150,81902004)Guangdong Basic and Applied Basic Research Foundation(Nos.2023A1515012193,2023A1515110025,2023A1515012575,2023A1515011962)+6 种基金Shenzhen Fundamental Research Program(Nos.JCYJ20220530144605012,JCYJ20240813150438050)China Postdoctoral Science Foundation(Nos.2023M744090,GZC20233296)Research Start-up Fund of Post-doctoral of SAHSYSU(No.ZSQYRSFPD0071)Distinguished Young Scientists projects by Guangdong Second Provincial General Hospital(No.2024E005)Guangdong International Science and Technology Cooperation Project(No.2023A0505050120)Shenzhen International Cooperative Research Project(No.GJHZ20220913142401003)Open Fund Key Project of the Guangdong Provincial Key Laboratory of Digestive Cancer Research(No.GPKLDCR202201Z)。
文摘T-cell acute lymphoblastic leukemia(T-ALL)is a common yet severe pediatric cancer treated with Lasparaginase(ASP).To boost the treatment's effectiveness and lessen its toxicity,enzyme@MOF nanoparticles were engineered with a hyaluronic acid(HA)-targeted polyethylene glycol(PEG)surface.These nanoparticles,termed ASP@MOF/PEG-HA,showed efficient uptake by drug-resistant T-ALL cells.The p Hsensitive zeolitic imidazolate framework-8(ZIF-8)based metal-organic framework(MOF)nanoparticles allowed the encapsulated ASP to significantly increase cytotoxicity against T-ALL cells.Furthermore,HA's ability to bind to T-ALL cells with elevated CD44 expression further induced apoptosis in CD44^(+) T-ALL cells with poor prognosis.In animal models,the nanoparticles improved survival rates and reduced the burden of leukemia,demonstrating substantial anti-leukemia effects.Thus,these nanoparticles offer an effective treatment approach for drug-resistant T-ALL cells characterized by increased CD44 expression.
基金Supported by the CAMS Innovation Fund for Medical Sciences(CIFMS)(2021-I2M-1-060).
文摘Introduction:Emerging and re-emerging transfusion-transmitted arboviruses remain a persistent public health challenge to global blood safety.This study aims to establish a comprehensive nucleic acid testing(NAT)quality control system for Dengue virus(DENV),Zika virus(ZIKV),and Chikungunya virus(CHIKV)screening in blood donations to evaluate the performance of domestic screening reagents,and to assess the prevalence of these arboviruses in border regions.Methods:Pseudovirus quality control materials based on the Moloney murine leukemia virus(MMLV)vector was constructed to evaluate the limit of detection(LoD)and precision of six blood screening reagents.An external quality assessment(EQA)was conducted across eight central blood stations in Guangxi Zhuang Aotonomous Region and Yunnan Provinces.These blood stations employed either reagent A or E for DENV/ZIKV/CHIKV triplex-assay screening of blood donor samples collected during epidemic seasons(June–August)in 2022 and 2023.Results:The six reagents exhibited varied LoD.All evaluated reagents exhibited excellent precision with coefficient of variation(CV)values<5%.All eight central blood stations achieved EQA scores above 80.In 2022,a total of 45,383 blood samples were screened,with no positive cases detected.In 2023,44,972 blood donors were screened,and nine samples tested positive at the Xishuangbanna central blood station.Confirmatory testing verified six Dengue virus serotype 1(DENV-1)infections among these cases.Conclusions:This study successfully established a robust quality assurance system for NAT-based arbovirus screening in China.The detection of DENV-positive samples underscore the persisting risk of transfusion-transmitted infections in endemic regions.Continued surveillance and enhanced screening strategies are essential to safeguard blood safety,particularly in arboviral hotspot regions with tropical/subtropical climates prone to recurrent outbreaks.
基金supported by the National Natural Science Foundation of China (21474015, 21774023)Science and Technology Commission of Shanghai Municipality (14ZR1402300)
文摘Covalent organic frameworks (COFs) are well known as the next generation of shape-persistent zeolite analogues, which have brought new impetus to the development of porous organic materials as well as two-dimensional polymers. Since the advent of COFs in 2005, many striking findings have definitely proven their great potentials expanding applications across energy,environment and healthcare fields. With thorough exploration over a decade, research interest has been drawn on the scientific challenges on chemistry, while making full play of COF values has remained far from satisfactory yet. Thus opening an avenue to modulating COF assemblies on the multi-scale is no longer just an option, but a necessity for matching the application requirements with enhanced performances. In this mini-review, we summarize the recent progress on design of nanoscale COFs with varying forms. Detailed description is concentrated on the synthetic strategies of COF assemblies such as spheres, fibers,tubes, coatings and films, thereby shedding light on the flexible manipulation over dimensions, compositions and morphologies.Meanwhile, the advanced applications of nanoscale COFs have been discussed here with comparison of their bulky counterparts.
