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A time-space network-based model for transportation service optimization of China Railway Express
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作者 Weichuan Yin Wenhu Hu +2 位作者 Xueting Yan Bo Peng Xiaoling Yang 《High-Speed Railway》 2024年第3期153-163,共11页
This paper describes the development and optimization plans for the China Railway Express(CR Express).As a new type of international land transport organization,CR Express has emerged with the continuous expansion of ... This paper describes the development and optimization plans for the China Railway Express(CR Express).As a new type of international land transport organization,CR Express has emerged with the continuous expansion of China toward European investment and trade,and in particular,has expanded with the continuous progress of the One Belt and One Road(OBOR)initiative.In addition to improving the service quality of CR Express,the operating costs must be reduced for developing“smart railways”that serve“smart cities”.We propose a dualobjective-based function mathematical optimization model;the satisfaction of the cargo owner is considered,and the timeliness,transportation capacity,and goods category constraints of CR Express transportation are designed.Moreover,we present the normalized equivalent method of the two-objective function of the model.Finally,a case study is conducted against the background of certain trains in the western corridor of CR Express to validate the effectiveness of the model and research methods proposed in this study. 展开更多
关键词 One Belt and One Road China Railway Express Transportation service Mathematical optimization time-space network
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Locally Enhanced Flow and Electric Fields Through a Tip Effect for Efficient Flow‑Electrode Capacitive Deionization
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作者 Ziquan Wang Xiangfeng Chen +5 位作者 Yuan Zhang Jie Ma Zhiqun Lin Amor Abdelkader Maria‑Magdalena Titirici Libo Deng 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期1-17,共17页
Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer... Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current collectors.Herein,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport significantly.The effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal resistance.With the voltage increased from 1.0 to 1.5 and 2.0 V,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current collectors.Meanwhile,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current collectors.Additionally,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability. 展开更多
关键词 Flow-electrode Capacitive deionization Current collector Tip effect DESALINATION
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Late effects of the treatment of childhood cancer
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作者 Jelena Roganovic 《World Journal of Clinical Cases》 SCIE 2025年第7期6-12,共7页
Excellent progress has been made in the last few decades in the cure rates of pediatric malignancies,with more than 80%of children with cancer who have access to contemporary treatment being cured.However,the therapie... Excellent progress has been made in the last few decades in the cure rates of pediatric malignancies,with more than 80%of children with cancer who have access to contemporary treatment being cured.However,the therapies responsible for this survival can also produce adverse physical and psychological long-term outcomes,referred to as late effects,which appear months to years after the completion of cancer treatment.Research has shown that 60%to 90%of childhood cancer survivors(CCSs)develop one or more chronic health conditions,and 20%to 80%of survivors experience severe or life-threatening complications during adulthood.Therefore,understanding the late side effects of such treatments is important to improve the health and quality of life of the growing population of CCSs. 展开更多
关键词 SURVIVORSHIP CANCER CHILDREN TREATMENT Late effects
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Earthquake-Affected Time-Space Domain, Recurrence Interval and Effective Preparation Time of Earthquakes
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作者 Wang Shengzu and Zhang ZongchunInstitute of Geology & Laboratory of Tectonophysics, China Seismological Bureau, Beijing 100029, China 《Earthquake Research in China》 2002年第4期380-395,共16页
The study shows that earthquake-affected time-space domain (ETSD), i.e. a time-space range in which strong earthquakes are unable to occur owing to the influence of a prior earthquake occurring, shows a hyperbolic mar... The study shows that earthquake-affected time-space domain (ETSD), i.e. a time-space range in which strong earthquakes are unable to occur owing to the influence of a prior earthquake occurring, shows a hyperbolic margin curve in the t(time)-r(distance) coordinate plane, which has a maximum affected radius r 0 at t=0 and a maximum influence time t 0 (i.e. the in-situ recurrence interval of earthquakes) at r=0. Based on the time-distance distributions of posterior earthquakes relative to prior ones in the regions of North China, Northwest China, Qinghai-Xizang (Tibet) plateau and Southwest China, the optimized and 90%-confidence margin curves are estimated using optimization and statistical analysis methods. This indicates that the concept and method of ETSD with 3-dimension (time-distance-magnitudes) instead of those of “recurrence interval" with 1-dimension (time) or 2-dimension (time-magnitude) provides a new approach to understanding the fluctuation of seismic activities, estimating the effective earthquake-preparation time of potential hypocenters, and therefore improving the medium- and long-term prediction of strong earthquakes. 展开更多
关键词 Earthquake-affected time-space domain Recurrence interval Affected radius effective earthquake-preparation time
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Novel Methodologies for Preventing Crack Propagation in Steel Gas Pipelines Considering the Temperature Effect
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作者 Nurlan Zhangabay Ulzhan Ibraimova +4 位作者 Marco Bonopera Ulanbator Suleimenov Konstantin Avramov Maryna Chernobryvko Aigerim Yessengali 《Structural Durability & Health Monitoring》 EI 2025年第1期1-23,共23页
Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crac... Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crack,strengthened by steel wire wrapping.The effects of the thread tensile force of the steel winding in the form of single rings at the crack edges and the wires with different winding diameters and pitches were also studied.The results showed that the strengthening was preferably executed at a minimum value of the thread tensile force,which was 6.4%more effective than that at its maximum value.The analysis of the influence of the winding dia-meters showed that the equivalent stresses increased by 32%from the beginning of the crack growth until the wire broke.The increment in winding diameter decelerated the disclosure of the edge crack and reduced its length by 8.2%.The analysis of the influence of the winding pitch showed that decreasing the distance between the winding turns also led to a 33.6%reduction in the length of the straight crack and a 7.9%reduction in the maximum stres-ses on the strengthened pipeline cross-section.The analysis of the temperature effect on the pipeline material,within a range from-40℃ to+50℃,resulted in a crack length change of up to 5.8%.As the temperature dropped,the crack length decreased.Within such a temperature range,the maximum stresses were observed along the cen-tral area of the crack,which were equal to 413 MPa at+50℃ and 440 MPa at-40℃.The results also showed that the presence of the steel winding in the pipeline significantly reduced the length of crack propagation up to 8.4 times,depending on the temperature effect and design parameters of prestressing.This work integrated the existing methods for crack localization along steel gas pipelines. 展开更多
关键词 Crack propagation finite-element internal pressure PRESTRESSING steel gas pipeline temperature effect
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Relationship between parenting stress and behavioral and emotional problems in preschool children: A mediation effect analysis
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作者 Zhi-Wei Fu Yue-Jing Li +3 位作者 Ran Yu Rui-Qing Guo Li-Xia Gao Sheng-Xia Zhao 《World Journal of Psychiatry》 SCIE 2025年第1期128-136,共9页
BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current statu... BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current status of family rearing,parental stress,and behavioral and emotional problems of preschool children and to analyze the mediating effect of the current status of family rearing on parental stress and behavioral/emo-tional problems.METHODS We use convenience sampling to select 258 preschool children in the physical examination center of our hospital from October 2021 to September 2023.The children and their parents were evaluated using a questionnaire survey.Pearson's correlation was used to analyze the correlation between child behavioral and emotional problems and parental stress and family rearing,and the structural equation model was constructed to test the mediating effect.RESULTS The score for behavioral/emotional problems of 258 preschool children was(27.54±3.63),the score for parental stress was(87.64±11.34),and the score for parental family rearing was(31.54±5.24).There was a positive correlation between the behavioral and emotional problems of the children and the“hostile/mandatory”parenting style;meanwhile,showed a negative correlation with the“support/participation”parenting style(all P<0.05).The intermediary effect value between the family upbringing of parents in parental stress and children's behavior problems was 29.89%.CONCLUSION Parental family upbringing has a mediating effect between parental stress and behavioral and emotional problems of children.Despite paying attention to the behavioral and emotional problems of preschool-age children,clinical medical staff should provide correct and reasonable parenting advice to their parents to promote the mental health of preschool-age children. 展开更多
关键词 Preschool children Parenting stress Children's behavioral and emotional problems Family rearing Mediating effect
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Variations in quantifying patient reported outcome measures to estimate treatment effect
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作者 Sathish Muthu Srujun Vadranapu 《World Journal of Methodology》 2025年第2期44-53,共10页
In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence ... In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence regarding patient care by recording the change in outcomes for a particular treatment to a given condition and finally to understand whether a patient will benefit from a particular treatment and to quantify the treatment effect.For any PROM to be usable in health care,we need it to be reliable,encapsulating the points of interest with the potential to detect any real change.Using structured outcome measures routinely in clinical practice helps the physician to understand the functional limitation of a patient that would otherwise not be clear in an office interview,and this allows the physician and patient to have a meaningful conver-sation as well as a customized plan for each patient.Having mentioned the rationale and the benefits of PROMs,understanding the quantification process is crucial before embarking on management decisions.A better interpretation of change needs to identify the treatment effect based on clinical relevance for a given condition.There are a multiple set of measurement indices to serve this effect and most of them are used interchangeably without clear demarcation on their differences.This article details the various quantification metrics used to evaluate the treatment effect using PROMs,their limitations and the scope of usage and implementation in clinical practice. 展开更多
关键词 Patient-reported outcome measures Treatment effect Minimal clinical important difference Patient-accepted symptom state Minimum detectable change ORTHOPEDICS
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TIME-SPACE CONCEPT FOR PRECISION MEASUREMENT 被引量:4
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作者 LIU Xiaokang PENG Donglin ZHU Ge WANG Xianquan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第3期112-115,共4页
The transformation between time and space is discussed. To improve real-time response speed of intelligent measuring system, the concept of exchanging program execution time with more circuitry is presented working in... The transformation between time and space is discussed. To improve real-time response speed of intelligent measuring system, the concept of exchanging program execution time with more circuitry is presented working in cycle mode. Displacement measuring by magnification is achieved with period measurement by magnification. To change the condition that traditional precision measurement depends on machining precision greatly, the concept of measuring space with time and theory of time-space coordinate transformation are proposed. Guided by the idea of measuring space with time, differential frequency measurement system and time grating displacement sensor are developed based on the proposed novel methods. And high-precision measurement is achieved without high-precision manufacture, which embeds the remarkable characteristics of low cost but high precision to the devices. Experiment and test results conform the validity of the proposed time-space concept. 展开更多
关键词 time-space Precision measurement Control flow Differential frequency Time grating
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Adaptive time-space resource and waveform control for collocated MIMO radar with simultaneous multi-beam 被引量:4
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作者 CHENG Ting LI Xi +1 位作者 TAN Qianqian SU Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第1期47-59,共13页
Collocated multiple input multiple output(MIMO)radar,which has agile multi-beam working mode,can offer enhanced multiple targets tracking(MTT)ability.In detail,it can illuminate different targets simultaneously with m... Collocated multiple input multiple output(MIMO)radar,which has agile multi-beam working mode,can offer enhanced multiple targets tracking(MTT)ability.In detail,it can illuminate different targets simultaneously with multi-beam or one wide beam among multi-beam,providing greater degree of freedom in system resource control.An adaptive time-space resource and waveform control optimization model for the collocated MIMO radar with simultaneous multi-beam is proposed in this paper.The aim of the proposed scheme is to improve the overall tracking accuracy and meanwhile minimize the resource consumption under the guarantee of effective targets detection.A resource and waveform control algorithm which integrates the genetic algorithm(GA)is proposed to solve the optimization problem.The optimal transmitting waveform parameters,system sampling period,sub-array number,binary radar tracking parameterχ_i(t_k),transmitting energy and multi-beam direction vector combination are chosen adaptively,where the first one realizes the waveform control and the latter five realize the timespace resource allocation.Simulation results demonstrate the effectiveness of the proposed control method. 展开更多
关键词 multiple targets tracking(MTT) collocated multiple input multiple output(MIMO)radar time-space resource allocation waveform control
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Adaptive resource management for multi-target tracking in co-located MIMO radar based on time-space joint allocation 被引量:1
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作者 SU Yang CHENG Ting +2 位作者 HE Zishu LI Xi LU Yanxi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第5期916-927,共12页
Compared with the traditional phased array radar, the co-located multiple-input multiple-output(MIMO) radar is able to transmit orthogonal waveforms to form different illuminating modes, providing a larger freedom deg... Compared with the traditional phased array radar, the co-located multiple-input multiple-output(MIMO) radar is able to transmit orthogonal waveforms to form different illuminating modes, providing a larger freedom degree in radar resource management. In order to implement the effective resource management for the co-located MIMO radar in multi-target tracking,this paper proposes a resource management optimization model,where the system resource consumption and the tracking accuracy requirements are considered comprehensively. An adaptive resource management algorithm for the co-located MIMO radar is obtained based on the proposed model, where the sub-array number, sampling period, transmitting energy, beam direction and working mode are adaptively controlled to realize the time-space resource joint allocation. Simulation results demonstrate the superiority of the proposed algorithm. Furthermore, the co-located MIMO radar using the proposed algorithm can satisfy the predetermined tracking accuracy requirements with less comprehensive cost compared with the phased array radar. 展开更多
关键词 co-located multiple-input multiple-output(MIMO)radar adaptive resource management multi-target tracking sub-array division time-space joint allocation
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240 nm AlGaN-based deep ultraviolet micro-LEDs:size effect versus edge effect 被引量:2
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作者 Shunpeng Lu Jiangxiao Bai +6 位作者 Hongbo Li Ke Jiang Jianwei Ben Shanli Zhang Zi-Hui Zhang Xiaojuan Sun Dabing Li 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期55-62,共8页
240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge ef... 240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge effects.Here,it is revealed that the peak optical output power increases by 81.83%with the size shrinking from 50.0 to 25.0μm.Thereinto,the LEE increases by 26.21%and the LEE enhancement mainly comes from the sidewall light extraction.Most notably,transversemagnetic(TM)mode light intensifies faster as the size shrinks due to the tilted mesa side-wall and Al reflector design.However,when it turns to 12.5μm sized micro-LEDs,the output power is lower than 25.0μm sized ones.The underlying mechanism is that even though protected by SiO2 passivation,the edge effect which leads to current leakage and Shockley-Read-Hall(SRH)recombination deteriorates rapidly with the size further shrinking.Moreover,the ratio of the p-contact area to mesa area is much lower,which deteriorates the p-type current spreading at the mesa edge.These findings show a role of thumb for the design of high efficiency micro-LEDs with wavelength below 250 nm,which will pave the way for wide applications of deep ultraviolet(DUV)micro-LEDs. 展开更多
关键词 ALGAN deep ultraviolet micro-LEDs light extraction efficiency size effect edge effect
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A Time-Space Optimal Parallel Sorting on a Hypercube
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作者 QI JIANXIAN (Beijing Institute of System Engineering P. O.Box 9702-19, Beijing, People ’s Repuslic of China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期465-469,共5页
In this paper we discuss a parallel sorting algorithm on a hypercube. Its time complexity is O(n logn/p) +O(n). Here, P is the number of processors available and n, the amount of items to be sorted. Take the problem o... In this paper we discuss a parallel sorting algorithm on a hypercube. Its time complexity is O(n logn/p) +O(n). Here, P is the number of processors available and n, the amount of items to be sorted. Take the problem of time-space optimization into consideration, when P≤ O(log n), this algorithm is both timespace optimal and cost optimization. But this means only speedup is O(P) and it is not linear speedup. Therefore, we further discuss relevant parallel efficiency problems. 展开更多
关键词 HYPERCUBE Parallel Sorting time-space Optimal EFFICIENCY COST Operations.
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A "TIME-SPACE" RELATED DESIGN METHOD OF FREEZING WALL
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作者 陈湘生 《Journal of Coal Science & Engineering(China)》 1996年第2期63-66,共4页
Artificially ground freezing (AGF) is one of the main methods to establish temporary support for shaft sinking in unstable water bearing strata. Domde (1915) formula based on frozen soil strength has widely been used ... Artificially ground freezing (AGF) is one of the main methods to establish temporary support for shaft sinking in unstable water bearing strata. Domde (1915) formula based on frozen soil strength has widely been used for designing freezing wall thickness. However, it can not ensure the stability of freezing wall, nor guarantee the safety of shaft construction as frozen depth increases in unstable water bearing strata. F A. Auld (1985, 1988)[1,2] presented a design method of freezing wall, which is on the basis of strength and stability, together with deformation of freezing wall. This paper, according to the practice in China, describes a "time -space" related design method for deep freezing wall. The method is based on "time-space" concept, which includes influence of excavation rate of advance, unsupported length of freezing wall and the sump state on inward deformation of freezing wall, and the allowable pipe deformation caused by inward deformation of freezing wall. Finally, successful application of this method to the large scale coal mine-Jining No. 2 Mine[3] in Shandong Province of China is presented. It saved much investment compared with F. A. Auld’s design for the same mine. 展开更多
关键词 ground freezing freezing wall DESIGN time-space concept
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A traffic model of optical networks based on time-space complexity and traffic grooming
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作者 赵永利 《High Technology Letters》 EI CAS 2009年第2期198-202,共5页
This paper researched the traffic of optical networks in time-space complexity,proposed a novel traf-fic model for complex optical networks based on traffic grooming,designed a traffic generator GTS(gener-ator based o... This paper researched the traffic of optical networks in time-space complexity,proposed a novel traf-fic model for complex optical networks based on traffic grooming,designed a traffic generator GTS(gener-ator based on time and space)with 'centralized+distributed' idea,and then made a simulation in Clanguage.Experiments results show that GTS can produce the virtual network topology which can changedynamically with the characteristic of scaling-free network.GTS can also groom the different traffic andtrigger them under real-time or scheduling mechanisms,generating different optical connections.Thistraffic model is convenient for the simulation of optical networks considering the traffic complexity. 展开更多
关键词 optical networks traffic model time-space complexity scaling-free SELF-SIMILARITY traffic grooming
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Finite Difference Schemes for Time-Space Fractional Diffusion Equations in One-and Two-Dimensions
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作者 Yu Wang Min Cai 《Communications on Applied Mathematics and Computation》 EI 2023年第4期1674-1696,共23页
In this paper,finite difference schemes for solving time-space fractional diffusion equations in one dimension and two dimensions are proposed.The temporal derivative is in the Caputo-Hadamard sense for both cases.The... In this paper,finite difference schemes for solving time-space fractional diffusion equations in one dimension and two dimensions are proposed.The temporal derivative is in the Caputo-Hadamard sense for both cases.The spatial derivative for the one-dimensional equation is of Riesz definition and the two-dimensional spatial derivative is given by the fractional Laplacian.The schemes are proved to be unconditionally stable and convergent.The numerical results are in line with the theoretical analysis. 展开更多
关键词 time-space fractional diffusion equation Caputo-Hadamard derivative Riesz derivative Fractional Laplacian Numerical analysis
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Evaluation of the intracellular lipid-lowering effect of polyphenols extract from highland barley in HepG2 cells 被引量:3
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作者 Yijun Yao Zhifang Li +2 位作者 Bowen Qin Xingrong Ju Lifeng Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期454-461,共8页
Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinat... Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4. 展开更多
关键词 Highland barley Polyphenols extract Lipid-lowering effect HepG2 cells
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Engineering Strategies for Suppressing the Shuttle Effect in Lithium–Sulfur Batteries 被引量:2
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作者 Jiayi Li Li Gao +7 位作者 Fengying Pan Cheng Gong Limeng Sun Hong Gao Jinqiang Zhang Yufei Zhao Guoxiu Wang Hao Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期187-221,共35页
Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost.Nevertheless,the shuttle effect of firm multi-step two-elect... Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost.Nevertheless,the shuttle effect of firm multi-step two-electron reaction between sulfur and lithium in liquid electrolyte makes the capacity much smaller than the theoretical value.Many methods were proposed for inhibiting the shuttle effect of polysulfide,improving corresponding redox kinetics and enhancing the integral performance of Li–S batteries.Here,we will comprehensively and systematically summarize the strategies for inhibiting the shuttle effect from all components of Li–S batteries.First,the electrochemical principles/mechanism and origin of the shuttle effect are described in detail.Moreover,the efficient strategies,including boosting the sulfur conversion rate of sulfur,confining sulfur or lithium polysulfides(LPS)within cathode host,confining LPS in the shield layer,and preventing LPS from contacting the anode,will be discussed to suppress the shuttle effect.Then,recent advances in inhibition of shuttle effect in cathode,electrolyte,separator,and anode with the aforementioned strategies have been summarized to direct the further design of efficient materials for Li–S batteries.Finally,we present prospects for inhibition of the LPS shuttle and potential development directions in Li–S batteries. 展开更多
关键词 Shuttle effect Designed strategies Li-S battery Lithium polysulfides
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Rockburst criterion and evaluation method for potential rockburst pit depth considering excavation damage effect 被引量:2
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作者 Jinhao Dai Fengqiang Gong Lei Xu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1649-1666,共18页
Excavation-induced disturbances in deep tunnels will lead to deterioration of rock properties and formation of excavation damaged zone(EDZ).This excavation damage effect may affect the potential rockburst pit depth.Ta... Excavation-induced disturbances in deep tunnels will lead to deterioration of rock properties and formation of excavation damaged zone(EDZ).This excavation damage effect may affect the potential rockburst pit depth.Taking two diversion tunnels of Jinping II hydropower station for example,the relationship between rockburst pit depth and excavation damage effect is first surveyed.The results indicate that the rockburst pit depth in tunnels with severe damage to rock masses is relatively large.Subsequently,the excavation-induced damage effect is characterized by disturbance factor D based on the Hoek-Brown criterion and wave velocity method.It is found that the EDZ could be further divided into a high-damage zone(HDZ)with D=1 and weak-damage zone(WDZ),and D decays from one to zero linearly.For this,a quantitative evaluation method for potential rockburst pit depth is established by presenting a three-element rockburst criterion considering rock strength,geostress and disturbance factor.The evaluation results obtained by this method match well with actual observations.In addition,the weakening of rock mass strength promotes the formation and expansion of potential rockburst pits.The potential rockburst pit depth is positively correlated with HDZ and WDZ depths,and the HDZ depth has a significant contribution to the potential rockburst pit depth. 展开更多
关键词 Deep tunnel ROCKBURST Rockburst pit Excavation damage effect Hoek-Brown criterion
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Experimental study on the effect of water absorption level on rockburst occurrence of sandstone 被引量:1
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作者 Dongqiao Liu Jie Sun +3 位作者 Pengfei He Manchao He Binghao Cao Yuanyuan Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期136-152,共17页
To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and ... To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and acoustic emission(AE)system are used to monitor the rockburst process.The effect of water on sandstone rockburst and the prevention mechanism of water on sandstone rockburst are analyzed from the perspective of energy and failure mode.The results show that the higher the ab-sorption degree,the lower the intensity of the rockburst after absorbing water on single side of sand-stone.This is reflected in the fact that with the increase in the water absorption level,the ejection velocity of rockburst fragments is smaller,the depth of the rockburst pit is shallower,and the AE energy is smaller.Under the water absorption level of 100%,the magnitude of rockburst intensity changes from medium to slight.The prevention mechanism of water on sandstone rockburst is that water reduces the capacity of sandstone to store strain energy and accelerates the expansion of shear cracks,which is not conducive to the occurrence of plate cracking before rockburst,and destroys the conditions for rockburst incubation. 展开更多
关键词 ROCKBURST Water Prevention effect Crack evolution
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High responsivity photodetectors based on graphene/WSe_(2) heterostructure by photogating effect 被引量:1
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作者 李淑萍 雷挺 +5 位作者 严仲兴 王燕 张黎可 涂华垚 时文华 曾中明 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期728-733,共6页
Graphene, with its zero-bandgap electronic structure, is a highly promising ultra-broadband light absorbing material.However, the performance of graphene-based photodetectors is limited by weak absorption efficiency a... Graphene, with its zero-bandgap electronic structure, is a highly promising ultra-broadband light absorbing material.However, the performance of graphene-based photodetectors is limited by weak absorption efficiency and rapid recombination of photoexcited carriers, leading to poor photodetection performance. Here, inspired by the photogating effect, we demonstrated a highly sensitive photodetector based on graphene/WSe_(2) vertical heterostructure where the WSe_(2) layer acts as both the light absorption layer and the localized grating layer. The graphene conductive channel is induced to produce more carriers by capacitive coupling. Due to the strong light absorption and high external quantum efficiency of multilayer WSe_(2), as well as the high carrier mobility of graphene, a high photocurrent is generated in the vertical heterostructure. As a result, the photodetector exhibits ultra-high responsivity of 3.85×10~4A/W and external quantum efficiency of 1.3 × 10~7%.This finding demonstrates that photogating structures can effectively enhance the sensitivity of graphene-based photodetectors and may have great potential applications in future optoelectronic devices. 展开更多
关键词 WSe_(2) HETEROSTRUCTURE PHOTODETECTOR photogating effect
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