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Adenosine kinase and ADAL coordinate detoxification of modified adenosines to safeguard metabolism
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作者 Akiko Ogawa 《四川生理科学杂志》 2025年第8期1719-1719,共1页
RNA contains diverse post-transcriptional modifications,and its catabolic breakdown yields numerous modified nucleosides requiring correct processing,but the mechanisms remain unknown.Here,we demonstrate that three RN... RNA contains diverse post-transcriptional modifications,and its catabolic breakdown yields numerous modified nucleosides requiring correct processing,but the mechanisms remain unknown.Here,we demonstrate that three RNA-derived modified adenosines,N6-methyladenosine(m6A),N6,N6-dimethyladenosine(m6,6A),and N6-isopentenyladenosine(i6A),are sequentially metabolized into inosine monophosphate(IMP)to mitigate their intrinsic cytotoxicity. 展开更多
关键词 adenosine kinase modified adenosines modified adenosinesn methyladenosine m n n dimethyladenosine m catabolic breakdown modified nucleosides DETOXIFICATION inosine monophosphate imp adal
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基于Modified Page模型的玉米含水率预测及动力学分析
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作者 齐迹 李健 +4 位作者 窦雪峰 孙旸 胡雅婷 李伟 张芳靖 《吉林农业大学学报》 北大核心 2025年第2期373-378,共6页
为了研究玉米的干燥特性以提高干燥效率,分析了微波功率、装载量、籽粒的初始含水率及初始温度等指标,得到了玉米籽粒干燥特性的变化规律。结果表明:微波干燥功率和温度对玉米籽粒的干燥特性有着很大的影响。使用SPSS运用回归分析和数... 为了研究玉米的干燥特性以提高干燥效率,分析了微波功率、装载量、籽粒的初始含水率及初始温度等指标,得到了玉米籽粒干燥特性的变化规律。结果表明:微波干燥功率和温度对玉米籽粒的干燥特性有着很大的影响。使用SPSS运用回归分析和数值分析方法对玉米微波干燥试验数据与Modified Page模型进行拟合,得到其评价指标R^(2)>0.991 0,χ^(2)<0.053 4,RMES<0.087,并经过验证试验,实测值与模型的预测值具有良好的相关系数(R^(2)>0.99),这表明该模型有利于提高干燥效率,提升玉米含水率的预测精度,以期确保玉米品质和安全。 展开更多
关键词 玉米 modified Page模型 微波干燥 含水率 回归分析
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Establishment of a field visualization detection method for multiplex recombinase polymerase amplification combined with CRISPR/Cas12a in genetically modified crops 被引量:1
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作者 YAN Jingying NI Liang +2 位作者 SHEN Xingyu LÜ Bingtao LI Yu 《浙江大学学报(农业与生命科学版)》 北大核心 2025年第3期391-401,共11页
With the approval of more and more genetically modified(GM)crops in our country,GM safety management has become more important.Transgenic detection is a major approach for transgenic safety management.Nevertheless,a c... With the approval of more and more genetically modified(GM)crops in our country,GM safety management has become more important.Transgenic detection is a major approach for transgenic safety management.Nevertheless,a convenient and visual technique with low equipment requirements and high sensitivity for the field detection of GM plants is still lacking.On the basis of the existing recombinase polymerase amplification(RPA)technique,we developed a multiplex RPA(multi-RPA)method that can simultaneously detect three transgenic elements,including the cauliflower mosaic virus 35S gene(CaMV35S)promoter,neomycin phosphotransferaseⅡgene(NptⅡ)and hygromycin B phosphotransferase gene(Hyg),thus improving the detection rate.Moreover,we coupled this multi-RPA technique with the CRISPR/Cas12a reporter system,which enabled the detection results to be clearly observed by naked eyes under ultraviolet(UV)light(254 nm;which could be achieved by a portable UV flashlight),therefore establishing a multi-RPA visual detection technique.Compared with the traditional test strip detection method,this multi-RPA-CRISPR/Cas12a technique has the higher specificity,higher sensitivity,wider application range and lower cost.Compared with other polymerase chain reaction(PCR)techniques,it also has the advantages of low equipment requirements and visualization,making it a potentially feasible method for the field detection of GM plants. 展开更多
关键词 genetically modified crop recombinase polymerase amplification CRISPR/Cas12a field detection
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State of the art review on inorganic powders modified asphalt materials: Reducing the temperature of asphalt pavement 被引量:1
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作者 Chaohui Wang Tonghao Zhang +3 位作者 Anquan Li Dawei Zhao Luqing Liu Qian Chen 《Journal of Road Engineering》 2025年第2期279-296,共18页
To reduce the temperature diseases of asphalt pavement,improve the service quality of road and extend service life,the research of inorganic powders that reduce the temperature of asphalt pavements was systematically ... To reduce the temperature diseases of asphalt pavement,improve the service quality of road and extend service life,the research of inorganic powders that reduce the temperature of asphalt pavements was systematically sorted out.The common types,physicochemical properties and application methods of inorganic powders were defined.The road performances of modified asphalt and its mixture were evaluated.The modification mechanism of inorganic powders in asphalt was analyzed.On this basis,the cooling effect and cooling mechanism of inorganic powders was revealed.The results indicate that inorganic powders are classified into hollow,porous,and energy conversion types.The high-temperature performance of inorganic powders modified asphalt and its mixture is significantly improved,while there is no significant change in low-temperature performance and water stability.The average increase in rutting resistance factor(G*/sin(δ))and dynamic stability is 40%–72%and 30%–50%,respectively.The modification mechanism of inorganic powders in asphalt is physical blending.The thermal conductivity of hollow and porous inorganic powders modified asphalt mixture decreases by 30.05%and 43.14%,respectively.The temperature of hollow,porous and energy conversion inorganic powders modified asphalt mixture at 5 cm decreases by 2.3 ℃–3.5 ℃,0.8 ℃–3.7 ℃and 4.1 ℃–4.7℃,respectively.Hollow and porous inorganic powders block heat conduction,while energy conversion inorganic powders achieve cooling through their functional properties. 展开更多
关键词 Road materials COOLING modified asphalt Inorganic powders PERFORMANCES
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On Modified Rota-Baxter Hom-Lie Algebras 被引量:1
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作者 Wen TENG 《Journal of Mathematical Research with Applications》 2025年第2期163-178,共16页
Semenov-Tian-Shansky has given the solution of the modified classical Yang-Baxter equation, which was called the modified r-matrix. Relevant studies have been extensive in recent times. In this paper, we introduce the... Semenov-Tian-Shansky has given the solution of the modified classical Yang-Baxter equation, which was called the modified r-matrix. Relevant studies have been extensive in recent times. In this paper, we introduce the concept and representations of modified RotaBaxter Hom-Lie algebras. We develop a cohomology of modified Rota-Baxter Hom-Lie algebras with coefficients in a suitable representation. As applications, we study formal deformations and abelian extensions of modified Rota-Baxter Hom-Lie algebras in terms of second cohomology groups. 展开更多
关键词 Hom-Lie algebra modified Rota-Baxter operator cohomology deformation abelian extension
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Assessing the Hydrological and Social Effects of Three Gorges Reservoir Using a Modified SWAT Model 被引量:1
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作者 Xin Dai Lunche Wang +3 位作者 Qian Cao Zigeng Niu Zengliang Luo Yuhua Luo 《Journal of Earth Science》 2025年第4期1793-1807,共15页
As a crucial human activity,dam construction can profoundly impact the surface hydrology patterns.The Three Gorges Reservoir(TGR),as one of the largest hydraulic engineering projects in the world,has gained continuous... As a crucial human activity,dam construction can profoundly impact the surface hydrology patterns.The Three Gorges Reservoir(TGR),as one of the largest hydraulic engineering projects in the world,has gained continuous attention for its eco-hydrological effects.However,further investigation is necessary to understand the runoff and social impacts of the TGR on the Upper Yangtze River.This study first employed a modified SWAT model to simulate runoff,compared scenarios with and without the TGR,and finally evaluated water supply and demand in the Upper Yangtze River.The results showed a significant increasing trend in the surface water area of the Upper Yangtze River from 2000-2020.The modified SWAT model performs well in simulating the runoff,with Nash-Sutcliffe Efficiency and Percent Bias improved by 0.04-0.30 and 2-31.90,respectively.Scenario simulation results revealed that the TGR reduced seasonal differences in runoff.During the flood season,the runoff volume at the Yichang Station in the scenario with the TGR is lower than in the scenario without the TGR,peaking at 4500 m3/s.Conversely,in the dry season,the runoff volume of the scenario with TGR is higher,with a maximum increase of 1500 m3/s.The region exhibiting the greatest runoff variations is the Yangtze River's main stem in the Three Gorges Reservoir region.Besides,the TGR notably alleviated the water supply-demand imbalance in Chongqing during the winter and spring seasons,with a maximum increase of 0.16 in the supplydemand index.This study can contribute significantly to understanding the natural and social impacts of the TGR from the perspective of hydrological and scenario simulation. 展开更多
关键词 Three Gorges Reservoir the Upper Yangtze River a modified SWAT model water supply water demand
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Nucleoside modified mRNA-lipid nanoparticles as a new delivery platform for the repair of the injured spinal cord
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作者 Krisztián Pajer Tamás Bellák Antal Nógrádi 《Neural Regeneration Research》 SCIE CAS 2025年第8期2311-2312,共2页
Spinal cord injury and treatment opportunities:The adult mammalian spinal cord has a very limited capacity for spontaneous regeneration due to various intrinsic molecular and cellular factors.Although the spinal cord ... Spinal cord injury and treatment opportunities:The adult mammalian spinal cord has a very limited capacity for spontaneous regeneration due to various intrinsic molecular and cellular factors.Although the spinal cord neurons have the capacity to regenerate their axons,the expression of growth inhibitory factors,lack or suppression of proper guidance cues,and profound inflammatory responses do not permit successful regeneration(Khyeam et al.,2021). 展开更多
关键词 INJURED capacity modified
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Grid-Connected/Islanded Switching Control Strategy for Photovoltaic Storage Hybrid Inverters Based on Modified Chimpanzee Optimization Algorithm
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作者 Chao Zhou Narisu Wang +1 位作者 Fuyin Ni Wenchao Zhang 《Energy Engineering》 EI 2025年第1期265-284,共20页
Uneven power distribution,transient voltage,and frequency deviations are observed in the photovoltaic storage hybrid inverter during the switching between grid-connected and island modes.In response to these issues,th... Uneven power distribution,transient voltage,and frequency deviations are observed in the photovoltaic storage hybrid inverter during the switching between grid-connected and island modes.In response to these issues,this paper proposes a grid-connected/island switching control strategy for photovoltaic storage hybrid inverters based on the modified chimpanzee optimization algorithm.The proposed strategy incorporates coupling compensation and power differentiation elements based on the traditional droop control.Then,it combines the angular frequency and voltage amplitude adjustments provided by the phase-locked loop-free pre-synchronization control strategy.Precise pre-synchronization is achieved by regulating the virtual current to zero and aligning the photovoltaic storage hybrid inverter with the grid voltage.Additionally,two novel operators,learning and emotional behaviors are introduced to enhance the optimization precision of the chimpanzee algorithm.These operators ensure high-precision and high-reliability optimization of the droop control parameters for photovoltaic storage hybrid inverters.A Simulink model was constructed for simulation analysis,which validated the optimized control strategy’s ability to evenly distribute power under load transients.This strategy effectively mitigated transient voltage and current surges during mode transitions.Consequently,seamless and efficient switching between gridconnected and island modes was achieved for the photovoltaic storage hybrid inverter.The enhanced energy utilization efficiency,in turn,offers robust technical support for grid stability. 展开更多
关键词 Photovoltaic storage hybrid inverters modified chimpanzee optimization algorithm droop control seamless switching
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Graphene Oxide on Rheological and Self-healing Properties of Modified Asphalt
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作者 LIU Qinbao ZHAO Yan +1 位作者 GAO Honggang YAN Luchun 《材料科学与工程学报》 北大核心 2025年第1期80-89,共10页
Graphene oxide nanomaterials are increasingly used in various fields due to their superior properties.In order to study the influence of graphene oxide additives on the performance of modified asphalt,in this study,gr... Graphene oxide nanomaterials are increasingly used in various fields due to their superior properties.In order to study the influence of graphene oxide additives on the performance of modified asphalt,in this study,graphene oxide modified asphalt was prepared and characteristics was studied including the high deformation resistance performance and the self-healing property of modified asphalt.Functional groups and morphology of graphene oxide modified asphalt were described by Fourier transform infrared spectroscopy.The high deformation resistance performance and self-healing effect of asphalt samples were obtained through dynamic slear rheometer(DSR)test.Results shows that graphene oxide dispersions improve the performance of asphalt relatively well compared to graphene oxide powder.There is no chemical reaction between graphene oxide and asphalt,but physical connection.The addition of graphene oxide improved the high deformation resistance of modified asphalt and expedited the self-healing ability of asphalt under fatigue load. 展开更多
关键词 Graphene Oxide modified asphalt Rheological property SELF-HEALING
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Parametric Dependence of Modified Yukawa Potential and Consequent Structure Changes of 2D Magnetized Complex Plasma
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作者 Li Xingyang Li Fei +2 位作者 Ma Jinghan Li Xinru Kong Wei 《南开大学学报(自然科学版)》 北大核心 2025年第2期78-86,共9页
For the magnetized complex plasma,dependences of modified Yukawa potential on the gov-erning parameters,viz.,mass ratio md/mi,number ratio nd/ne0,charge magnitude Q/e,and temperature ratio Te/Ti are investigated.It is... For the magnetized complex plasma,dependences of modified Yukawa potential on the gov-erning parameters,viz.,mass ratio md/mi,number ratio nd/ne0,charge magnitude Q/e,and temperature ratio Te/Ti are investigated.It is found that md/mi,nd/ne0 and Q/e contribute to the coupling strength of the system,and Te/Ti contributes to the shielding cloud surrounding the charged dust particles.Further analysis shows that the modified Yukawa potential depends on Te/Ti.The consequent structure changes of the system are discussed based on the Langevin dynamics simulation.It is found that the variation of Ham-iltonian contributes to the equilibrium structure of the system. 展开更多
关键词 complex plasma magnetic field modified Yukawa potential STRUCTURE
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Deformations and extensions of modified λ-differential Lie-Yamaguti algebras
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作者 TENG Wen PAN Yuewei 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第4期115-127,共13页
The modifiedλ-differential Lie-Yamaguti algebras are considered,in which a modifiedλ-differential Lie-Yamaguti algebra consisting of a Lie-Yamaguti algebra and a modifiedλ-differential operator.First we introduce t... The modifiedλ-differential Lie-Yamaguti algebras are considered,in which a modifiedλ-differential Lie-Yamaguti algebra consisting of a Lie-Yamaguti algebra and a modifiedλ-differential operator.First we introduce the representation of modifiedλ-differential Lie-Yamaguti algebras.Furthermore,we establish the cohomology of a modifiedλ-differential Lie-Yamaguti algebra with coefficients in a representation.Finally,we investigate the one-parameter formal deformations and Abelian extensions of modifiedλ-differential Lie-Yamaguti algebras using the second cohomology group. 展开更多
关键词 Lie-Yamaguti algebra modifiedλ-differential operator representation and cohomology one-parameter formal deformation Abelian extension
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Nonlinear waves for a variable-coefficient modified Kadomtsev-Petviashvili system in plasma physics and electrodynamics
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作者 Guang-Mei Wei Yu-Xin Song +1 位作者 Tian-Chi Xing Shu Miao 《Communications in Theoretical Physics》 2025年第1期23-34,共12页
In this paper,a variable-coefficient modified Kadomtsev-Petviashvili(vcm KP)system is investigated by modeling the propagation of electromagnetic waves in an isotropic charge-free infinite ferromagnetic thin film and ... In this paper,a variable-coefficient modified Kadomtsev-Petviashvili(vcm KP)system is investigated by modeling the propagation of electromagnetic waves in an isotropic charge-free infinite ferromagnetic thin film and nonlinear waves in plasma physics and electrodynamics.Painlevéanalysis is given out,and an auto-B?cklund transformation is constructed via the truncated Painlevéexpansion.Based on the auto-B?cklund transformation,analytic solutions are given,including the solitonic,periodic and rational solutions.Using the Lie symmetry approach,infinitesimal generators and symmetry groups are presented.With the Lagrangian,the vcm KP equation is shown to be nonlinearly self-adjoint.Moreover,conservation laws for the vcm KP equation are derived by means of a general conservation theorem.Besides,the physical characteristics of the influences of the coefficient parameters on the solutions are discussed graphically.Those solutions have comprehensive implications for the propagation of solitary waves in nonuniform backgrounds. 展开更多
关键词 modified Kadomtsev-Petviashvili equation Lie symmetry optimal system nonlinear self-adjointness conservation law symbolic computation
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Experimental Study and a Modified Model for Temperature-Recovery Stress of Shape Memory Alloy Wire under Different Temperatures
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作者 Zhi-Xiang Wei Wen-Wei Wang +2 位作者 Yan-Jie Xue Wu-Tong Zhang Qiu-Di Huang 《Structural Durability & Health Monitoring》 2025年第2期347-364,共18页
To investigate the performance of utilizing the shape memory effect of SMA(Shape Memory Alloy)wire to generate recovery stress,this paper performed single heating recovery stress tests and reciprocating heating-coolin... To investigate the performance of utilizing the shape memory effect of SMA(Shape Memory Alloy)wire to generate recovery stress,this paper performed single heating recovery stress tests and reciprocating heating-cooling recovery stress tests on SMA wire under varying initial strain conditions.The effects of various strains and different energized heating methods on the recovery stress of SMA wires were explored in the single heating tests.The SMA wire was strained from 2%to 8%initially,and two distinct heating approaches were employed:one using a large current interval for rapid heating and one using a small current interval for slower heating.The experimental outcomes reveal that during a single heating cycle,the temperature-recovery stress relationship of SMA wire exhibits three distinct stages:the martensite phase stage,the transition stage from martensite to austenite phase,and the austenite phase stage.Notably,the choice of heating method does not influence the maximum recovery stress value,and the correlation between initial strain and maximum recovery stress is predominantly linear.Moreover,conducting the reciprocating temperature rise and fall performance test is important to better simulate the scenario in practical engineering where multiple recovery stress in SMA wires for structural repair.In this test,two temperature cycling methods were studied:interval rise and fall,as well as direct rise and fall.In the case of utilizing the interval temperature rise and fall method,it was observed that the recovery stress associated with cooling was significantly higher than that corresponding to heating at the same temperature.Furthermore,the recovery stress was lower upon subsequent heating than that measured during the previous heating cycle.Based on the experimental results,a prediction model for the temperature-recovery stress relationship has been proposed to simplify numerical calculations.It is hoped that an approximate temperaturerecovery stress curve can be obtained from the parameters of the SMA wire.The calculated values derived from this model show good alignment with the measured values,indicating its reliability. 展开更多
关键词 SMA wire TEMPERATURE recovery stress modified model phase transition
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Application of modified Roux-en-Y digestive tract reconstruction in total gastrectomy for patients with gastric cancer
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作者 Jing Yu Min Li +6 位作者 Xiang-Zhi Qin Lei Gong Long Qin Zhen-Bing Lv Wei Guo Bin Huang Yun-Hong Tian 《World Journal of Gastrointestinal Surgery》 2025年第6期206-216,共11页
BACKGROUND At present,the concept of surgical treatment of gastric cancer(GC)has changed from“radical treatment”to“care for patients”to a certain extent.The reconstruction method is the most likely to affect the p... BACKGROUND At present,the concept of surgical treatment of gastric cancer(GC)has changed from“radical treatment”to“care for patients”to a certain extent.The reconstruction method is the most likely to affect the postoperative life of the patient.Currently,the traditional Roux-en-Y esophagojejunostomy anastomosis is a commonly used method for gastrointestinal reconstruction after total gastrectomy for GC.However,more recent studies have shown that the traditional Roux-en-Y anastomosis is complicated in operation procedure,with more reconstruction steps and longer reconstruction time,and the incidence of postoperative complications such as adhesive intestinal obstruction,internal abdominal hernia and volvulus is high.Moreover,the incidence of Roux stasis syndrome is 10%-30%after traditional Roux-en-Y reconstruction.Thus,we modified the traditional Roux-en-Y alimentary tract reconstruction,and designed a new digestive tract reconstruction method for laparoscopy-assisted Roux-en-Y anastomosis for total gastrectomy of GC.AIM To evaluate the clinical advantages,feasibility,and safety of a modified Roux-en-Y digestive tract reconstruction in laparoscopy-assisted total gastrectomy for the treatment of GC compared with the traditional Roux-en-Y method.METHODS Ninety-seven patients who underwent laparoscopy-assisted D2 radical gastrectomy(total gastrectomy)for GC were divided into two groups:fifty-four in the conventional Roux-en-Y reconstruction group(Orr group)and forty-three in the modified Roux-en-Y reconstruction group(the modified group).Perioperative and short-term outcomes were analyzed,including complications,postoperative weight loss,hemoglobin levels,and nutritional status.RESULTS The Orr group and the modified group showed no statistically significant differences in baseline characteristics.Compared with the Orr group,the modified group had shorter digestive tract reconstruction and operation times,less intraoperative bleeding,and shorter postoperative hospital stays compared to the Orr group.Although both groups had similar amounts of intraoperative blood loss,postoperative recovery times,and hospital expenses,the Orr group experienced longer operation times and digestive tract reconstruction times.Furthermore,the modified Roux-en-Y group demonstrated significantly fewer short-term and long-term complications,with a reduced incidence of reflux esophagitis and improved nutritional status.CONCLUSION The modified Roux-en-Y digestive tract reconstruction method after laparoscopy-assisted total gastrectomy for GC offers safety,simplicity,and a reduction in bile reflux.This method shortens operation times and minimizes postoperative complications,aligns with modern rapid rehabilitation surgery trends and potentially improves patient prognosis and overall survival.This method warrants further clinical application and promotion. 展开更多
关键词 Gastric cancer modified Roux-en-Y Gastrointestinal reconstruction Total gastrectomy ROUX-EN-Y
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A rock damage model considering shear failure by modified logistic growth theory
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作者 Kai Chen Roberto Cudmani Andres Peña 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1321-1355,共35页
Localized rock failures,like cracks or shear bands,demand specific attention in modeling for solids and structures.This is due to the uncertainty of conventional continuum-based mechanical models when localized inelas... Localized rock failures,like cracks or shear bands,demand specific attention in modeling for solids and structures.This is due to the uncertainty of conventional continuum-based mechanical models when localized inelastic deformation has emerged.In such scenarios,as macroscopic inelastic reactions are primarily influenced by deformation and microstructural alterations within the localized area,internal variables that signify these microstructural changes should be established within this zone.Thus,localized deformation characteristics of rocks are studied here by the preset angle shear experiment.A method based on shear displacement and shear stress differences is proposed to identify the compaction,yielding,and residual points for enhancing the model's effectiveness and minimizing subjective influences.Next,a mechanical model for the localized shear band is depicted as an elasto-plastic model outlining the stress-displacement relation across both sides of the shear band.Incorporating damage theory and an elasto-plastic model,a proposed damage model is introduced to replicate shear stressdisplacement responses and localized damage evolution in intact rocks experiencing shear failure.Subsequently,a novel nonlinear mathematical model based on modified logistic growth theory is proposed for depicting the shear band's damage evolution pattern.Thereafter,an innovative damage model is proposed to effectively encompass diverse rock material behaviors,including elasticity,plasticity,and softening behaviors.Ultimately,the effects of the preset angles,temperature,normal stresses and the residual shear strength are carefully discussed.This discovery enhances rock research in the proposed damage model,particularly regarding shear failure mode. 展开更多
关键词 Damage model Shear failure LOCALIZATION Shear band modified growth theory Damage evolution
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Application of modified two-point hedging policy in groundwater resources planning in the Kashan Plain Aquifer
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作者 Marzie Ghorbaniaghdam Hossein Khozeymehnezhad +1 位作者 Mohsen Pourreza bilondi Hoda Ghasemie 《Journal of Groundwater Science and Engineering》 2025年第1期62-73,共12页
Effective management of water resources,especially groundwater,is crucial and requires a precise understanding of aquifer characteristics,imposed stresses,and the groundwater balance.Simulation-optimization models pla... Effective management of water resources,especially groundwater,is crucial and requires a precise understanding of aquifer characteristics,imposed stresses,and the groundwater balance.Simulation-optimization models plays a vital role in guiding planners toword sustainable long-term aquifer exploita-tion.This study simulated monthly water table variations in the Kashan Plain over a ten-year period from 2008 to 2019 across 125 stress periods using the GMS model.The model was calibrated for both steady-state and transient conditions for the 2008–2016 period and validated for the 2016–2019 period.Results indicated a 4.4 m decline in groundwater levels over the 10-year study period.Given the plain's location in a arid climatic zone with limited effective precipitation for aquifer recharge,the study focused on ground-water extraction management.A modified two-point hedging policy was employed as a solution to mitigate critical groundwater depletion,reducing the annual drawdown rate from 0.44 m to 0.31 m and conserving 255 million cubic meters(mcm)of water annually.Although this approach slightly decreased reliability(i.e.the number of months meeting full water demands),it effectively minimized the risk of severe droughts and irreparable damages.This policy offers managers a dynamical and intelligent tool for regulating groundwater extraction,balancing aquifer sustainability with agricultural and urban water requirements. 展开更多
关键词 Calibration GMS Groundwater simulation-optimization model modified two-point hedging policy Sustainable operation
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Interannual Variation of Summertime Modified Circumpolar Deep Water Intrusions into Prydz Bay,East Antarctica
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作者 LIU Yaqian SHI Jiuxin +3 位作者 SUN Yongming HOU Saisai XIE Chunhu WILLIAMS Guy D. 《Journal of Ocean University of China》 2025年第3期533-544,共12页
The characteristics of modified Circumpolar Deep Water(mCDW)on the continental shelf in Prydz Bay,East Antarctica,are studied based on hydrographic data obtained by the Chinese National Antarctic Research Expeditions ... The characteristics of modified Circumpolar Deep Water(mCDW)on the continental shelf in Prydz Bay,East Antarctica,are studied based on hydrographic data obtained by the Chinese National Antarctic Research Expeditions across 14 summers from 1999 to 2022.In austral summer,the mCDW upwells along the upper continental slope then intrudes on the continental shelf across the shelf break in a warm tongue that gradually upwells poleward.The mCDW intrusion at the 73°E section is relatively weaker in December and stronger in February while showing significant interannual variability.During strong intrusions(January 2000 and February 2003),the mCDW extends southward to 68°S and upwells to 50 m,whereas the mCDW only reaches the shelf break during weak intrusions(December 2004,January 2006,January 2011,and February 2015).The intensity of the mCDW intrusions correlates strongly with the accumulated wind stress curl(30 days prior)north of the shelf break(73.5°-78.0°E,64.5°-66.0°S).The summertime westerly winds play a key role in regulating the interannual variability of mCDW intrusion onto the continental shelf.A southward shift of the westerly winds promotes the upwelling and southward intrusion of mCDW across the shelf break.In addition,mCDW at 73°E can reach as far as 68°S due to the southward flow of mCDW being hindered by a northward outflowing branch of the coastal current at the Amery Ice Shelf(AIS)front.In austral summer,the mCDW had never been observed at the section along the AIS front;thus,it cannot directly contribute to the basal melting of the ice shelf. 展开更多
关键词 modified Circumpolar Deep Water SUMMERTIME interannual variability Prydz Bay ANTARCTICA
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Enhanced removal of polystyrene nanoplastics by air flotation modified by dodecyltrimethylammonium chloride:Performance and mechanism
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作者 Jinhui Xu Yanting Zhang +6 位作者 Kecheng Wen Xinyu Wang Zhiwei Yang Yuan Huang Guozhong Zheng Lupeng Huang Jing Zhang 《Chinese Chemical Letters》 2025年第5期588-594,共7页
Nanoplastics exhibit greater environmental biotoxicity than microplastics and can be ingested by humans through major routes such as tap water,bottled water and other drinking water.Nanoplastics present a challenge fo... Nanoplastics exhibit greater environmental biotoxicity than microplastics and can be ingested by humans through major routes such as tap water,bottled water and other drinking water.Nanoplastics present a challenge for air flotation due to their minute particle size,negative surface potential,and similar density to water.This study employed dodecyltrimethylammonium chloride(DTAC)as a modifier to improve conventional air flotation,which significantly enhanced the removal of polystyrene nanoplastics(PSNPs).Conventional air flotation removed only 3.09%of PSNPs,while air flotation modified by dodecyltrimethylammonium chloride(DTAC-modified air flotation)increased the removal of PSNPs to 98.05%.The analysis of the DTAC-modified air flotation mechanism was conducted using a combination of instruments,including a zeta potential analyzer,contact angle meter,laser particle size meter,high definition camera,scanning electron microscope(SEM),energy dispersive spectrometer(EDS)and Fourier transform infrared spectrometer(FTIR).The results indicated that the incorporation of DTAC reversed the electrostatic repulsion between bubbles and PSNPs to electrostatic attraction,significantly enhancing the hydrophobic force in the system.This,in turn,improved the collision adhesion effect between bubbles and PSNPs.The experimental results indicated that even when the flotation time was reduced to 7min,the DTACmodified air flotation still achieved a high removal rate of 96.26%.Furthermore,changes in aeration,pH,and ionic strength did not significantly affect the performance of the modified air flotation for the removal of PSNPs.The removal rate of PSNPs in all three water bodies exceeded 95%.The DTAC-modified air flotation has excellent resistance to interference from complex conditions and shows great potential for practical application. 展开更多
关键词 Polystyrene nanoplastics Dodecyltrimethylammonium chloride modified air flotation MECHANISM Effectiveness and stability
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Effect of chemically modified starch on retrogradation and quality characteristics of semi-dry rice noodles
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作者 Xudong Yan Weirong Wen +3 位作者 Meng Li Shunjing Luo Jiangping Ye Chengmei Liu 《Grain & Oil Science and Technology》 2025年第1期13-20,共8页
Retrogradation of semi-dry rice noodles severely reduced their eating quality during storage.Three commonly used modified starches(oxidized starch,acetylated starch,and hydroxypropyl starch)were applied to investigate... Retrogradation of semi-dry rice noodles severely reduced their eating quality during storage.Three commonly used modified starches(oxidized starch,acetylated starch,and hydroxypropyl starch)were applied to investigate the anti-retrogradation effects of semi-dry rice noodles during cold storage.Loss of water content,migration of water,and increase in relative crystallinity,retrogradation enthalpy,and hardness could be retarded by adding chemically modified starches,especially hydroxypropyl starches.The effect of hydroxypropyl starch addition levels(2%,4%,6%,8%,and 10%)on the properties of rice flour and the edible quality of semi-dry rice noodles was further evaluated.The water solubility index of rice flour decreased with the addition of hydroxypropyl starch,while the swelling power showed the opposite trend.The quality of semi-dry rice noodles were improved with the addition of hydroxypropyl starch.Compared to the control,semi-dried rice noodles with 8%hydroxypropyl starch possessed superior properties,i.e.lower cooking loss(decreasing from 12.89%to 6.62%),lower adhesiveness(decreasing from 5.40 to 4.31 g·s),and higher hardness(rising from 10.89 to 13.81 N).These findings demonstrated that the incorporation of hydroxypropyl starch is a promising strategy for the preparation of semi-dry rice noodles with satisfactory cooking and edible qualities as well as a long shelf life. 展开更多
关键词 Semi-dry noodles modified starch RETROGRADATION Edible quality
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Stochastic response of steel columns subjected to lateral blast based on modified single degree of freedom(MSDOF)method
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作者 Mohammad Momeni Chiara Bedon +1 位作者 Mohammad Ali Hadianfard Sina Malekpour 《Resilient Cities and Structures》 2025年第1期1-15,共15页
This paper aims to evaluate the stochastic response of steel columns subjected to blast loads using the modified single degree of freedom(MSDOF)method,which assessed towards the conventional single degree of freedom(S... This paper aims to evaluate the stochastic response of steel columns subjected to blast loads using the modified single degree of freedom(MSDOF)method,which assessed towards the conventional single degree of freedom(SDOF)and the experimentally validated Finite Element(FE)methods(LSDYNA).For this purpose,special atten-tion is given to calculating the response of H-shaped steel columns under blast.The damage amount is determined based on the support rotation criterion,which is expressed as a function of their maximum lateral mid-span dis-placement.To account for uncertainties in input parameters and obtain the failure probability,the Monte Carlo simulation(MCS)method is employed,complemented by the Latin Hypercube Sampling(LHS)method to reduce the number of simulations.A parametric analysis is hence performed to examine the effect of several input pa-rameters(including both deterministic and probabilistic parameters)on the probability of column damage as a function of support rotation.First,the MSDOF method confirms its higher accuracy in estimating the probability of column damage due to blast,compared to the conventional SDOF.The collected results also show that un-certainties of several input parameters have significant effects on the column behavior.In particular,geometric parameters(including cross-sectional characteristics,boundary conditions and column length)have major effect on the corresponding column response,in the same way of input blast load parameters and material properties. 展开更多
关键词 Stochastic response Steel column Lateral blast UNCERTAINTY modified single degree of freedom(MSDOF) METHOD Parametric analysis
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