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Local failure mechanism of sand-blocking fence in latticed dune along desert roads

Journal of Mountain Science 2024年第2期21卷 526-537页

作者： LI Liangying LV Lele LI Qi WANG Zhenqiang YANG Youhai yin wenhua School of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730070China Ningxia Highway Survey and Design Institute Co Ltd Yinchuan 750001China

The latticed dunes in the Tengger Desert are widely distributed,and the sand-blocking fence placed here are highly susceptible to local failure due to complex wind-sand activities,posing a serious threat to the safe operation of the *** explore the local failure mechanism of sand-blocking fence in the latticed dune area,the local failure of sand-blocking fence in the latticed dune areas along the Wuhai-Maqin Highway in China was *** the first main ridge of the latticed dune as the placement location,the structure of the wind-sand flow field of sand-blocking fence placed at top,the bottom and the middle of windward slope was analyzed by Computational Fluid Dynamics(CFD).The results show that when placed at top of the first main ridge,the wind speed near the sand-blocking fence is the highest,up to 15.23 m/***,the wind load strength on the sand barrier is correspondingly larger,up to 232.61 N∙*** the strength of material continues to decrease,the nylon net is prone to *** roots of the angle steel posts are susceptible to hollowing by vortex action,which can cause sand-blocking fence to fall over in strong wind *** placed at the bottom of windward slope,wind speed drop near sand-blocking fence is greatest,with the decrease of 12.48-14.32 m/s compared to the original wind *** is highly likely to lead to large-scale deposition of sand particles and burial of the sand-blocking *** placed in the middle of windward slope,sand-blocking fence is subjected to less wind load strength(168.61N∙m-2)and sand particles are mostly deposited at the bottom of windward slope,with only a small amount of sand accumulating at the root of sand-blocking *** on field observations and numerical modelling results,when the sand-blocking fence is placed in latticed dune area,it should be placed in the middle of the windward slope of the first main ridge as a matter of *** the sand-blocking fence should be placed

关键词： Latticed dune Sand-blocking fence Local failure Numerical simulation Desert roads

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风积沙静动力特性实验研究

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黑龙江科学 2024年第16期15卷 1-4,11页

作者：刘琰君尹文华宁夏交投高速公路管理有限公司银川750001 北方民族大学银川750001

针对我国沙漠公路中风积沙填料经水泥改良后在荷载作用下静动力特性不明确问题,以沙漠公路为依托,进行无侧限抗压试验、三轴剪切试验及动模量与动强度特性试验。研究结果表明,随着水泥掺量的提高,风积沙填料的无侧限抗压强度逐渐增强,... 详细信息

针对我国沙漠公路中风积沙填料经水泥改良后在荷载作用下静动力特性不明确问题,以沙漠公路为依托,进行无侧限抗压试验、三轴剪切试验及动模量与动强度特性试验。研究结果表明,随着水泥掺量的提高,风积沙填料的无侧限抗压强度逐渐增强,而压实度对于抗压强度的影响并不明显。在水泥掺比低于6%时,改良后的风积沙表现出黏聚力和内摩擦角的快速增加,且一旦水泥掺量超过6%,这种增长趋势就开始减缓,随着围压和水泥掺量的增大,风积沙累积塑性应变逐渐减小,临界动应力增加,动模量显著提高。

关键词：风积沙无侧限抗压实验三轴剪切实验动模量与动强度实验

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Morphology of spinal cord extracellular matrix-derived acellular scaffolds fabricated in rats

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Neural Regeneration Research 2011年第10期6卷 767-771页

作者： wenhua yin Kaiwu Lu Dadi Jin Department of Orthopedic Surgery Yuebei People's Hospital Affiliated to Shantou Medical College of Shantou University Shaoguan 512026 Guangdong Province China Department of Spine Surgery Nanfang Hospital Affiliated to Southern Medical University Guangzhou 510515 Guangdong Province China Institute of Orthopedic Research Southern Medical University Guangzhou 510630 Guangdong Province China

Acellular peripheral allograft scaffolds can be fabricated using chemical extraction techniques,but methods for producing acellular scaffold derived from spinal cord tissue are not currently *** present study demonstrated that chemical extraction using Triton X-100 and sodium deoxycholate could be used to completely remove the cells,axons and neural sheaths in spinal cord extracellular matrix-derived *** matrix fibers were longitudinally arranged in a wave-like formation,and were connected by fiber ***-shaped fiber cages appeared and developed into bone trabecula-like *** natural structure of matrix fibers in the scaffolds was maintained;this helps to guide the differentiation and migration of implanted stem *** spinal cord extracellular matrix-derived scaffolds can provide an ideal substance for fabricating tissue-engineered spinal cord.

关键词： spinal cord extracellular matrix decellularization scaffolds neural regeneration

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Airborne PCDD/Fs in two e-waste recycling regions after stricter environmental regulations

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Journal of Environmental Sciences 2017年第12期29卷 3-10页

作者： Manwen Zhang Guixian Feng wenhua yin Bing Xie Mingzhong Ren Zhencheng Xu Sukun Zhang Zongwei Cai Partner State Key Laboratory of Environmental and Biological Analysis Department of Chemistry Hong Kong Baptist University South China Institute of Environmental Science Ministry of Environmental Protection

Since the 2010 s, the authorities of Guangdong province and local governments have enhanced law enforcement and environmental regulations to abolish open burning, acid washing, and other uncontrolled e-waste recycling activities. In this study, ambient air and indoor dust near different kinds of e-waste recycling processes were collected in Guiyu and Qingyuan to investigate the pollution status of particles and polychlorinated dibenzo-pdioxins and furans（PCDD/Fs） after stricter environmental regulations. PM_（2.5） and PCDD/Fs both showed significantly reduced levels in the two regions compared with the documented data. The congener distribution and principal component analysis results also confirmed the significant differences between the current PCDD/Fs pollution characterizations and the historical ones. The estimated total intake doses via air inhalation and dust ingestion of children in the recycling region of Guiyu ranged from 10 to 32 pg TEQ/（kg·day）, which far exceeded the tolerable daily intake（TDI） limit（1–4 pg TEQ/（kg·day）. Although the measurements showed a significant reduction of the release of PCDD/Fs, the pollution status was still considered severe in Guiyu town after stricter regulations were implemented.

关键词： Polychlorinated dibenzo-p-dioxins and furans E-waste recycling China Environmental regulation

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兰州西关什字站城一体化研究

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地下空间与工程学报 2022年第S2期18卷 515-519页

作者：殷文华中铁工程设计咨询集团有限公司北京100055

随着经济的发展和人民生活水平的提高,对于轨道交通站点的要求逐步由单一的交通功能转变为集交通、娱乐、休闲、商业、居住等多种功能为一体的多元化城市节点。对于兰州西关什字片区,以地铁1号线的建设为契机,提出了构建立体化交通体系... 详细信息

随着经济的发展和人民生活水平的提高,对于轨道交通站点的要求逐步由单一的交通功能转变为集交通、娱乐、休闲、商业、居住等多种功能为一体的多元化城市节点。对于兰州西关什字片区,以地铁1号线的建设为契机,提出了构建立体化交通体系、完善城市基础服务设施、功能整合、优化城市界面、一次规划分期实施等站城一体化设计思路,并依此形成了西关什字站城一体化设计方案。最后,对城市更新类站城一体化开发建设提出了三个建议:首先考虑结合车站优化片区内交通体系,实现人车分流,车站应与城市慢行交通系统无缝衔接;其次要完善片区内公共服务设施;最后应优化城市界面,整合城市功能,缝合城市空间,提升城市空间品质。

关键词：地下空间站城一体化站城融合轨道交通

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隧道内全封闭屏蔽门风压荷载特征研究

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铁道工程学报 2021年第11期38卷 92-96,103页

作者：彭斌殷文华李立中铁工程设计咨询集团有限公司北京100055

研究目的:列车在隧道内运行时产生的风压会对屏蔽门造成冲击,为研究隧道内全封闭屏蔽门在列车通过时所受风压荷载的变化特征,本文基于计算流体力学方法,采用动滑移网格处理运动列车,对高速列车通过屏蔽门时的非定常气动效应进行研究,分... 详细信息

研究目的:列车在隧道内运行时产生的风压会对屏蔽门造成冲击,为研究隧道内全封闭屏蔽门在列车通过时所受风压荷载的变化特征,本文基于计算流体力学方法,采用动滑移网格处理运动列车,对高速列车通过屏蔽门时的非定常气动效应进行研究,分析列车在不同速度下通过不同轨行区净过风面积时封闭式屏蔽门所受的风压荷载响应规律。研究结论:(1)动车组在隧道内以恒定速度运行时,封闭式屏蔽门上各监测点受到的压缩波和气动风压荷载呈现的规律一致;(2)动车组以不同速度运行时,屏蔽门所受初始压缩波最大值随车速增加呈线性增加;动车组以不同速度通过封闭式屏蔽门时,在屏蔽门上产生的气动荷载随速度的增加而增加,与车速平方呈正比;(3)动车组以相同速度通过封闭式屏蔽门时,屏蔽门受到的风压荷载水平受轨行区净过风面积影响,该面积越大,屏蔽门所受压缩波极值和风压荷载极值越小,反之则越大;轨行区净过风面积相同时,断面高宽比变化的影响微弱;(4)本研究成果可为隧道内屏蔽门设计提供理论依据。

关键词：全封闭屏蔽门风压荷载净过风面积

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Efficacy and safety of Jiawei Simiao powder combined with celecoxib for acute gouty arthritis:A meta-analysis

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Journal of Traditional Chinese Medical Sciences 2024年第3期11卷 283-292页

作者： Weiyu Jia Maoying Wei wenhua Zhang Dan yin Yijia Jiang Churan Wang Xiangdong Wang Yutong Fei Yanbing Gong Dongzhimen Hospital Beijing University of Chinese MedicineBeijing 100700China Nutrition and Cancer Biology Lab Jean Mayer USDA-Human Nutrition Research Center on Aging(HNRCA)at Tufts UniversityBoston 02111USA Centre for Evidence-Based Chinese Medicine Beijing University of Chinese MedicineBeijing 100029China

Objective To evaluate the efficacy and safety of Jiawei Simiao powder(JWSMP)combined with celecoxib for the treatment of acute gouty arthritis by conducting a meta-analysis of randomized controlled trials(RCTs).Methods The Chinese National Knowledge Infrastructure Databases,Chinese Scientific Journal Database,Wanfang,Cochrane Library,EMBASE,PubMed,and Web of Science databases were searched from inception until December *** variables were analyzed using the mean difference(MD)for analysis,and dichotomous variables were used as risk *** with similar characteristics were pooled for meta-analysis,and heterogeneity was assessed using *** Cochrane Handbook was used to assess the risk of bias and *** 5.3 software was used to perform the *** Thirteen RCTs involving 1007 patients were included in the *** quality of the included studies was low(unclear randomization processes and insufficient blinding reporting).The group receiving JWSMP combined with celecoxib showed significantly lower levels of serum uric acid(SUA,MD=−66.32,95%confidence interval(CI):−80.97 to−51.67,P<.001),erythrocyte sedimentation rate(ESR,MD=−6.05,95%CI:−8.29 to−3.82,P<.001),C-reactive protein(CRP,MD=−7.39,95%CI:−11.15,−3.63,P<.001),and joint pain score(VAS score,MD=−2.14,95%CI:−2.4 to−1.88,P<.001)compared to celecoxib ***,the JWSMP combined group had a higher total effective rate(risk ratio=1.22,95%CI:1.14 to 1.29,P<.001)and fewer adverse compared to celecoxib *** JWSMP combined with celecoxib is more effective than celecoxib alone in improving the total efficacy rate,alleviating joint pain,and improving SUA,ESR,and CRP *** also reduced the occurrence of adverse events caused by ***,the quality of the included studies was low,highlighting the need for further high-quality research with larger sample sizes and robust methodologies,such as double-blind randomization,to confirm these findings.

关键词： Jiawei Simiao powder Celecoxib Acute gouty arthritis Meta-analysis

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Hydrogen and nitrogen absorption properties of Ce-added Zr_(2)(Fe_(1-x)Ni_(x)) alloys

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Journal of Rare Earths 2024年第6期42卷 1136-1141,I0005页

作者： Kai yin Xiaopeng Liu State Key Laboratory of Advanced Materials for Smart Sensing GRINM Group Co.Ltd.Beijing10088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China General Research Institute of Nonferrous Metals Beijing100088China

To improve the nitriding resistance of Zr_(2)Fe alloy,the Ce-added Zr_(2)(Fe_(1-x)Ni_(x))(x=0,0.15,0.3,0.5)alloys were prepared by magnetic levitation melting *** effects of Ni substitution for Fe on the phase structure,hydrogen and nitrogen absorption properties of the alloys were investigated by X-ray diffraction,scanning electron microscopy and p-c isotherm *** experimental results show that Ni substitution can effectively inhibit the formation of both α-Zr and ZrFe_(2) phases and promote the formation of C16 structure Zr_(2)(Fe,Ni)phase,causing Ni-substituted alloys to exhibit low nitrogen absorption rate and *** 623 K under 0.5 MPa nitrogen pressure,the nitrogen absorption capacity of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy reaches to 0.8 mL/g,much lower than that of Zr_(2)Fe alloy(1.5 mL/g).Ni substitution decreases the crystal cell volume of the C_(16)Zr_(2)(Fe,Ni)phase,resulting in an increase in the hydrogen absorption equilibrium *** 623 K under 0.05 MPa hydrogen pressure,the hydrogen absorption capacity decreases from 1.46 wt%of Zr_(2)Fe alloy to 1.41 wt%of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy.

关键词： Zr_(2)Fe alloy Ce Pressure-composition isotherm Hydrogen absorption Nitrogen absorption Rare earths

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Rational surface charge engineering of haloalkane dehalogenase for boosting the enzymatic performance in organic solvent solutions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 276-285页

作者： yin Wu Yan Sun Department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Biocatalysis in organic solvents(OSs)has numerous important applications,but native enzymes in OSs often exhibit limited catalytic ***,we proposed a computation-aided surface charge engineering strategy to improve the catalytic performance of haloalkane dehalogenase DhaA in OSs based on the energetic analysis of substrate binding to the DhaA *** variants with enhanced OS resistance were obtained by replacing negative charged residues on the surface with positive charged residue(Arg).Particularly,a four-substitution variant E16R/E93R/E121R/E257R exhibited the best catalytic performance(five-fold improvement in OS resistance and seven-fold half-life increase in 40%(vol)dimethylsulfoxide).As a result,the overall catalytic performance of the variant could be at least 26 times higher than the wild-type *** spectroscopy and molecular dynamics simulation studies revealed that the residue substitution mainly enhanced OS resistance from four aspects:(a)improved the overall structural stability,(b)increased the hydrophobicity of the local microenvironment around the catalytic triad,(c)enriched the hydrophobic substrate around the enzyme molecule,and(d)lowered the contact frequency between OS molecules and the catalytic *** findings validate that computationaided surface charge engineering is an effective and ingenious rational strategy for tailoring enzyme performance in OSs.

关键词： Surface charge engineering Organic solvent resistance Molecular dynamics simulation Haloalkane dehalogenase

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A generalized presentation of multi-caloric effects based on exterior derivative theory and its applications

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Communications in Theoretical Physics 2024年第8期76卷 156-163页

作者： Jun yin School of Materials Science and Engineering Nankai UniversityTianjin 300350China School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China

The emerging concept of multi-caloric effects, introduced in 2010, entails the application of multiple interplay fields to a thermodynamic system. While multi-caloric effects are the main focus of experimental endeavors, theoretical considerations fall short of providing a thorough understanding. This paper introduces a comprehensive presentation on multi-caloric effects,employing the method and theory of exterior derivative formations. It addresses every aspect of thermodynamic systems, showcasing its applicability to multi-caloric materials(both singlephase and multi-phase materials), and its adaptability to different scenarios(either in single or multiple force fields). The formulation of Maxwell relationships, characterized by their generality and universality, enables a clear prediction in entropy and temperature, facilitating a distinct identification between independent and interdependent contributions from multi-caloric effects. These insights hold significant importance in designing and developing specialized thermodynamic materials, optimizing functional performances and exploring innovative mechanisms.

关键词： multicaloric effects Maxwell relations isothermal entropy adiabatic temperature

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