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Dynamic process analysis of the Niumiangou landslide triggered by the Wenchuan earthquake using the finite difference method and a modified discontinuous deformation analysis

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Journal of Mountain Science 2021年第4期18卷 1034-1048页

作者： huaNG Da MENG Qiu-jie SONG Yi-xiang CUI Sheng-hua CEN Duo-feng School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China

The Niumiangou landslide was the largest landslide triggered by the 2008 Wenchuan earthquake,which was significantly affected by the amplification effect of seismic acceleration.The ringshear experiments indicated that the materials in the source area of the Niumiangou landslide were subjected to friction degradation under a big shear displacement,which may result in rapid movement of the landslide.In order to better understand the landslide movement and study the effect of the friction degradation on movement mechanisms,the dynamic process of Niumiangou landslide was simulated with a new numerical method,which combines the finite difference method(FDM)and the discontinuous deformation analysis(DDA).First,the FDM was used to study the initiation time,amplification effect and velocity of the landslide.Afterwards,these initiation velocities were applied to the blocks in the DDA model by corresponding coordination in the FDM model.A displacementdependent friction model of the sliding surface was incorporated into DDA code to further understand the kinetic behavior of the landslide.The results show that the displacement-dependent friction strongly decreases the friction coefficient of sliding surface under a big displacement,which can obviously promote the run-out and velocity of landslide.The model output well matches the topographic map formed by the landslide.This implies that the proposed model can be applied to the simulation of earthquake-induced landslides with amplification effect,and the friction degradation model is important to clarify the movement mechanism of high-speed and long-distance landslides.

关键词： Wenchuan earthquake Discontinuous deformation analysis(DDA) Niumiangou landslide Amplification effects Displacement-dependent friction model

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Numerical study of seabed response and liquefaction around a jacket support offshore wind turbine foundation under combined wave and current loading

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Water Science and Engineering 2022年第1期15卷 78-88页

作者： Shu-xin Wei Zuo-dong Liang Lin cui hua-ling Zhai Dong-sheng Jeng School of Civil Engineering Qingdao University of TechnologyQingdao 266033China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China School of Engineering&Built Environment Griffith University Gold Coast CampusQueensland 4222Australia

The seabed instability induced by the transient liquefaction when exposed to wave-current may threaten the safety of offshore structures.In this study,the Reynolds-averaged Navier-Stokes(RANS)equations with the k-e turbulence model were used to imitate the fluid dynamics,and Biot's poro-elastic theory was used to simulate the transient seabed response.An in-house solver(porous-fluid-seabed-structure interactions-field operation and manipulation)integrating the flow model and seabed model with the finite volume method was developed.The present model was confirmed with published experimental results and then used to analyze the dynamic process of the fluid-seabed-structure interactions as well as seafloor liquefaction around the jacket foundation under wave-current loading.The simulated results showed that the depth and range for the liquefaction area around the jacket foundation tended to increase at first and then declined as the wave propagated forward in the absence of current.In addition,the results demonstrated that the liquefaction depth under current and wave in the same orientation was greater than that without current.It is worth mentioning that the downstream piles were more prone to liquefaction than the upstream piles when the forward current existed.

关键词： Jacket Wave and current Liquefaction Seafloor dynamic Fluid-seabed-structure interactions

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Tuning the electric transport behavior of AgCrSe_(2) by intrinsic defects

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Science China Chemistry 2021年第11期64卷 1970-1975页

作者： Yang hua Wei Bai sheng Wang Yunbo Wu shengtao cui Zhe Sun Chong Xiao Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei230026China Institute of Energy Hefei Comprehensive National Science CenterHefei230031China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei230029China

The two-dimensional(2 D)structure often leads to unusual phenomena for the impact of confined mean free path of carrier scattering.As a quasi-2 D layered material,Ag CrSe_(2)has a liquid-like phonon behavior for its unstable Ag atoms at service temperature,leading to the promising candidate for thermoelectricity and fast ionic conductor.However,the inferior electronic performance constrains its application prospects as a functional semiconductor,which provides broad opportunity to tune its electric behaviors by defect chemistry.In this work,we revealed abundant electric transport behaviors of Ag CrSe_(2)with different types of intrinsic defects.For example,the Ag CrSe_(2)changes from Anderson insulator to metal when Se defects become prevailing and the magnetoresistance alters its sign depending on the relative ratio of Ag and Cr defects.Our results reported here can give salutary boosting on regulating the electric properties of ternary transition metal selenide by defect chemistry.

关键词： electric transport defect layered material

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Rolling motion behavior of rockfall on gentle slope:an experimental approach

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Journal of Mountain Science 2017年第8期14卷 1550-1562页

作者： CUI Sheng-hua PEI Xiang-jun huaNG Run-qiu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology

The effects of slope surface material, slope gradient, block shape, and block mass conditions on rockfall rolling velocity were estimated with orthogonal test approach. Visual analysis shows that the importance of the factors is slope surface material > slope gradient > block shape > block mass. All the factors except block mass have the F value greater than the critical value, suggesting that these three factors are the key factors affecting the rockfall rolling velocity. Factor interaction analysis shows that the effect of the slope gradient relies largely on the slope surface conditions, and the block shape has little influence if the slope gradient is larger than a critical value. An empirical model considering the three key factors is proposed to estimate the rolling velocity, of which the error is limited to 5% of the testing value. This model is validated by 73 field tests, and the prediction shows excellent correlation with the site test. Thus, this analysis can be used as a tool in the rockfall behavior analysis.

关键词： Rockfall Rolling motion Experimen tapproach Gentle slope 0rthogonal test

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Protective effects of penehyclidine hydrochloride on acute lung injury caused by severe dichlorvos poisoning in swine

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Chinese Medical Journal 2013年第24期126卷 4764-4770页

作者： cui Juan LI Chun-sheng HE Xin-hua SONG Yu-guo Department of Emergency Medicine Beijing Meitan HospitalBeijing 100028 China Department of Emergency Medicine Department of Occupational Poisonings Department of Emergency Medicine BeijngChaoyang Hospital Capital Medical University Beijing 100020China

Background Organophosphate poisoning is an important health problem in developing countries which causes death mainly by inducing acute lung injury. In this study, we examined the effects of penehyclidine hydrochloride （PHC）, a selective M-receptor inhibitor, on dichlorvos-induced acute lung injury in swine. Methods Twenty-two female swines were randomly divided into control （n=5）, dichlorvos （n=6）, atropine （n=6）, and PHC （n=5） groups. Hemodynamic data, extravascular lung water index （EVLWI）, and pulmonary vascular permeability index （PVPI） were monitored; blood gas analysis and acetylcholinesterase （AchE） levels were measured. PaO2/FiO2, cardiac index （CI）, and pulmonary vascular resistance indices （PVRI） were calculated. At termination of the study, pulmonary tissue was collected for ATPase activity determination and wet to dry weight ratio （W/D） testing 6 hours post-poisoning. TUNEL assay, and Bax, Bcl-2, and caspase-3 expression were applied to pulmonary tissue, and histopathology was observed. Results After poisoning, PHC markedly decreased PVRI, increased CI more effectively than atropine. Anticholinergic treatment reduced W/D, apoptosis index （AI）, and mitigated injury to the structure of lung; however, PHC reduced AI and caspase-3 expression and improved Bcl-2/Bax more effectively than atropine. Atropine and PHC improved ATPase activities; a significant difference between groups was observed in Ca2＋-ATPase activity, but not Na＋-K＋-ATPase activity. Conclusions The PHC group showed mild impairment in pathology, less apoptotic cells, and little impact on cardiac function compared with the atropine group in dichlorvos-induced acute lung injury.

关键词： apoptosis adenosine triphosphatases dichlorvos, extravascular lung water index, acute lung injury, penehyelidine hydrochloride

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Arc characteristics of submerged arc welding with stainless steel wire

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International Journal of Minerals,Metallurgy and Materials 2014年第8期21卷 772-778页

作者： Ke Li Zhi-sheng Wu cui-rong Liu Feng-hua Chen College of Materials Science and Engineering Taiyuan University of Science and Technology

The arc characteristics of submerged arc welding （SAW） with stainless steel wire were studied by using Analysator Hannover （AH）. The tests were carded out under the same preset arc voltage combined with different welding currents. By comparing the probability density distribution （PDD） curves of arc voltage and welding current, the changes were analyzed, the metal transfer mode in SAW was deduced, and the characteristics of a stable arc were summarized. The analysis results show that, with an increase of welding parameters, the short-circuiting peak in the PDD curves of arc voltage decreases gradually until it disappears, and the dominant metal transfer mode changes from flux-wall guided transfer to projected transfer and then to streaming transfer. Moreover, when the PDD curves of arc voltage are both unimodal and generally symmetrical, the greater the peak probability and the smaller the peak span, the more stable the arc becomes.

关键词： submerged arc welding electric arc characteristics stainless steel wire metal transfer

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Effect of 5-AZn-2'-deoxycytidine on proliferation of human lung adenocarcinoma cell line A549 in vitro

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Asian Pacific Journal of Tropical Medicine 2013年第12期6卷 982-985页

作者： Na Li hua-Qiong huang Gen-sheng Zhang Wei cui Department of Intensive Care Unit Second Affiliated Hospital of Zhejiang University School of Medicine Department of Respiratory Medicine Second Affiliated Hospital of Zhejiang Unirersity School of Medicine

Objective:To explore effect of 5-AZn-2'-deoxycytidine on proliferation of human lung adenocarcinoma cell line A549 in vitro.Methods:Superoxide dismutase(SOD)activity was measured by hydroxylamine colorimetric method.Inhibition effect of 5-AZn-2'deoxycytidylic acid at different concentration and different time on growth of A549 cell was determined by MTT assay.Methylene dioxyamphetamine(MDA)was measured by throbarbituric acid colorimetric method.Effect of 5-AZn-2'deoxycytidylic acid on apoptosis of A549 cell was determined by Hoechst 33258 dyeing detection.Results:5-AZn-2'deoxycytidylic acid had significant inhibition effect on proliferation of A549 cells in vitro,and the inhibition was notably dependent on time and dosage during 48-72 h;SOD level was significantly lower than those of control group(P<0.05,P<0.01),MDA level was significantly higher than those in the control group(P<0.05,P<0.01).A549 cells began to be in apoptosis after using 5-AZn-2'deoxycytidylic acid.Conclusions:5-AZn-2'deoxycytidylic acid has significant inhibition effect on growth of A549 cell,and can lead the change of lipid peroxidation.It indicates that the mechanism has relationship with A549 cell cycle tissue and induction factor of apoptosis.

关键词： DAC A549 cell Lipid peroxidation Apoptosis

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Prognostic value of time to generalization in 71 Chinese patients with sporadic amyotrophic lateral sclerosis

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Chinese Medical Journal 2019年第9期132卷 1023-1027页

作者： Qiong-hua Sun Yan-Ran Li Wen-Jie Lan Fei Yang Fang cui Xu-sheng huang Department of Neurology Chinese People's Liberation Army General HospitalBeijing 100853China College of Medicine Nankai UniversityTianjin 300071China

Background:It is important to determine prognostic factors for the outcome of amyotrophic lateral sclerosis (ALS) at an early stage.The time taken for symptoms to spread from spinal or bulbar regions to both (time to generalization;TTG) is considered a strong predictor of survival;however,this has rarely been studied in Asian populations.The aim of this retrospective study was to evaluate potential factors affecting prognosis in Chinese patients with sporadic ALS,with a focus on the association between TTG and overall survival.Methods:Seventy-one patients with sporadic ALS who were hospitalized at Chinese PLA General Hospital from 2009 to 2016 were followed up until December 2017.Survival analysis was performed using univariate Kaplan-Meier log-rank and multivariate Cox proportional hazards models.The clinical data of the patients were recorded and analyzed.Variables studied were age at symptom onset,sex,site of symptom onset,diagnostic latency,TTG,diagnostic category,ALS Functional Rating Scale-revised score,percent predicted forced vital capacity (FVC%),and disease progression rate (DPR) at diagnosis.Results:The mean age at onset was 54 (SD = 10.2) years,and the median survival time from symptom onset was 41 months (95% confidence interval:34–47).By univariate analysis,factors independently affecting survival were age at symptom onset (Log rank = 15.652,P<0.0001),TTG (Log rank = 14.728,P<0.0001),diagnostic latency (Log rank = 11.997,P = 0.001),and DPR (Log rank = 6.50,P = 0.011).In the Cox multivariate model,TTG had the strongest impact on survival time (hazard ratio = 0.926,P = 0.01).Conclusions:TTG can be used as an effective indicator of prognosis in patients with sporadic ALS.

关键词： Amyotrophic lateral sclerosis Time to generalisation (TTG) Prognosis Survival

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Triarylborane π-electron systems with intramolecular charge-transfer transitions

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Chinese Chemical Letters 2016年第8期27卷 1131-1138,1464页

作者： Zuo-Bang Sun sheng-Yong Li Zhi-Qiang Liu cui-hua Zhao School of Chemistry and Chemical Engineering Key Laboratory of Special Functional Aggregated Materials Ministry of EducationShandong University State Key Laboratory of Crystal Materials Shandong University

The incorporation of B element into π-conjugated system is an efficient strategy to tune the steric and electronic structure and thus optoelectronic properties of π-electron systems.The vacant p orbital on the tricoordinate B center makes it exhibit several electronic and steric features,such as electron-accepting ability through p-π~＊ conjugation,the high Lewis acidity to coordinate with Lewis bases,as well as the steric bulk arising from the aryl substituent on the B center to get enough kinetic stability.As a result,the boryl group is a very unique electron acceptor.When an electron-donating amino group is present,the triarylboranes would display intense intramolecular charge transfer transitions,which lead to interesting optoelectronic properties and great utilities.This short review summarizes the recent progress in π-electron systems,which contain both B and N elements and thus display intramolecular charge-transfer transitions.The triarylboranes are introduced based on their structural features,including the linear π-system with boryl and amino groups at the terminal positions,the lateral borylsubstituted π-system with amino groups at the terminal positions,the biphenyl π-system with an amino and a boryl groups at o,o＇-positions,nonconjugated U- and V-shaped π-system,macrocylcic π-system with B and N embedded in the ring,B,N-bridged ladder-type π-system,as well as the polycyclicπ-system with B embedded in the center.

关键词： Triarylborane Electron-acceptor Electron-donor Charge-transfer

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基于改进麻雀搜索算法的北疆春玉米产量预测方法

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计算机工程与设计 2023年第8期44卷 2531-2540页

作者：崔兴华靳晟新疆农业大学计算机与信息工程学院新疆乌鲁木齐830052

针对新疆北疆地区在玉米生产中存在的生产效率低下问题,提出一种基于改进麻雀搜索算法的北疆春玉米产量预测方法。为改善麻雀搜索算法全局搜索能力弱的缺陷,加入Kent映射丰富初始种群的多样性,结合反向学习策略调整跟随者位置更新策略;... 详细信息

针对新疆北疆地区在玉米生产中存在的生产效率低下问题,提出一种基于改进麻雀搜索算法的北疆春玉米产量预测方法。为改善麻雀搜索算法全局搜索能力弱的缺陷,加入Kent映射丰富初始种群的多样性,结合反向学习策略调整跟随者位置更新策略;为增强易麻雀搜索算法跳出局部极值点的能力,引入融合柯西变异和高斯变异的食物源机制。通过数值实验将改进后的麻雀搜索算法与4种相关算法对比,结果表明,改进后的麻雀搜索算法在收敛速度及精度上更具优势。将改进的麻雀搜索算法与径向基神经网络结合构建玉米产量预测模型,并设计仿真实验验证了模型的有效性。

关键词：玉米麻雀搜索算法 Kent映射反向学习策略食物源机制径向基神经网络产量预测

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