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An Overview of Formation Mechanism and Disaster Characteristics of Post-seismic Debris Flows Triggered by Subsequent Rainstorms in Wenchuan Earthquake Extremely Stricken Areas

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Acta Geologica Sinica(English Edition) 2014年第4期88卷 1310-1328页

作者： NI Huayong TANG Chuan ZHENG Wanmo XU Ruge tian kai XU Wei State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu Institute of Geology and Mineral Resources China Geological Survey

The Wenchuan earthquake induced large amounts of debris flows and catastrophic incidents triggered by subsequent rainstorms occurred frequently in the past 6 rainy seasons, and thus resulted in serious casualties, huge economic loss and long-term impact. In this paper, post-seismic debris flows distributed in 10 Wenchuan earthquake extremely stricken counties were verified and debris flow database consisting of 609 debris flows was established based on detailed investigation organized by Land and Resources Department of Sichuan Province. Combined with database and related studies, the impact of Wenchuan earthquake on debris flows was analyzed. And then variation of formation conditions including rainfall threshold and landform condition was analyzed by contrasting pre-seismic and post-seismic debris flows. Followed are some typical viewpoints on initiation mechanism of post-seismic debris flows. In the end of this paper, characteristics of postseismic debris flows triggered by subsequent rainstorms were comprehensively summarized, such as regional group occurrence, high frequency, high viscosity, chain effect, huge dynamics, large scale and long duration. We hope this paper will be helpful in understanding the formation mechanism, disaster characteristics and prevention countermeasures of post-seismic debris flows in Wenchuan earthquake extremely stricken areas.

关键词： Wenchuan earthquake Post-seismic debris flow Gully-type debris flow Formationmechanism Disaster characteristic

Deammoniative Condensation of Primary Allylic Amines with Nonallylic Amines

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Chinese Journal of Chemistry 2014年第8期32卷 741-751页

作者： Yong Wang Manbo Li Xiantao Ma Congrong Liu Yonghong Gu Shi-kai tian Department of Chemistry University of Science and Technology of ChinaHefeiAnhui 230026China Department of Environmental Engineering Nanjing Institute of TechnologyNanjingJiangsu 211167China

An unprecedented deammoniative condensation reaction of primary allylic amines with nonallylic amines has been developed through C-N bond *** the presence of 5 mol%palladium diacetate,10 mol%1,4-bis(diphenylphosphino)butane(dppb),and 5 mol%p-toluenesulfonic acid(TsOH),a range of α-unbranched primary allylic amines smoothly underwent deammoniative condensation with nonallylic amines in an α-selective fashion to give structurally diverse secondary and tertiary amines in good to excellent yields and E *** dppb with racemic 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl(BINAP)permitted the deammoniative condensation of enantioenriched α-chiral primary allylic amines with nonallylic amines to proceed with complete retention of *** ionization(ESI)mass spectrometric analysis of the reaction mixture permitted the identification of some π-allylpalladium intermediates,and plausible mechanisms have been proposed to account for the regioselectivity and stereospecificity of the deammoniative condensation reaction.

关键词： amines deammoniation palladium substitution stereospecificity

Observation of tiny polarization rotation rate in total internal reflection via weak measurements

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Photonics Research 2017年第2期5卷 92-96页

作者： CHENGQUAN MI SHIZHEN CHEN XINXING ZHOU kai tian HAILU LUO SHUANGCHUN WEN Laboratory for Spin Photonics School of Physics and Electronics Hunan University Synergetic Innovation Center for Quantum Effects and Applications College of Physics and Information ScienceHunan Normal University

In this paper,we examine the tiny polarization rotation effect in total internal reflection due to the spin–orbit interaction of *** find that the tiny polarization rotation rate will induce a geometric phase gradient,which can be regarded as the physical origin of photonic spin Hall *** demonstrate that the spin-dependent splitting in position space is related to the polarization rotation in momentum space,while the spin-dependent splitting in momentum space is attributed to the polarization rotation in position ***,we introduce a quantum weak measurement to determine the tiny polarization rotation *** rotation rate in momentum space is obtained with 118 nm,which manifests itself as a spatial shift,and the rotation rate in position space is achieved with 38 μrad∕λ,which manifests itself as an angular *** investigation of the polarization rotation characteristics will provide insights into the photonic spin Hall effect and will enable us to better understand the spin–orbit interaction of light.

关键词： rate Observation of tiny polarization rotation rate in total internal reflection via weak measurements

Differentiation of adipose-derived stem cells toward nucleus pulposuslike cells induced by hypoxia and a three-dimensional chitosan-alginate gel scaffold in vitro

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Chinese Medical Journal 2014年第2期127卷 314-321页

作者： Zhang Zhicheng Li Fang tian Haiquan Guan kai Zhao Guangmin Shan Jianlin Ren Dajiang People's Liberation Army Institute of Orthopedics Beijing Army General Hospital Beijing 100700 China

Background Injectable three-dimensional （3D） scaffolds have the advantages of fluidity and moldability to fill irregularshaped defects,simple incorporation of bioactive factors,and limited surgical ***-derived stem cells （ADSCs） are multipotent and can be differentiated toward nucleus pulposus （NP）-Iike cells.A hypoxic environment may be important for differentiation to NP-like cells because the intervertebral disc is an avascular ***,we investigated the induction effects of hypoxia and an injectable 3D chitosan-alginate （C/A） gel scaffold on *** The C/A gel scaffold consisted of medical-grade chitosan and *** porosity was calculated by liquid displacement *** microstructure was analyzed by light and scanning electron *** were isolated and cultured by conventional *** 2 BrdU-labeled ADSCs were co-cultured with the C/A *** were divided into three groups （control,normoxia-induced,and hypoxia-induced groups）.In the control group,cells were cultured in 10％ FBS/***-induced and normoxia-induced groups were induced by adding transforming growth factor-β1,dexamethasone,vitamin C,sodium pyruvate,proline,bone morphogenetic protein-7,and 1％ ITS-plus to the culture medium and maintaining in 2％ and 20％ O2,*** and morphological changes were observed by light and electron *** were characterized by flow *** viability was investigated by BrdU *** and type Ⅱ collagen were measured by safranin O staining and the Sicool method,*** expression of hypoxia-inducing factor-1α （HIF-1α）,aggrecan,and Type Ⅱ collagen was determined by reverse transcription-polymerase chain *** C/A gels had porous exterior surfaces with 80.57％ porosity and 50-200 μm pore *** cytometric analysis of passage 2 rabbit ADSCs showed high CD90 expression,while CD45 expression was very *** morphology of induced ADSCs resembl

关键词： intervertebral disc degeneration adipose-derived stem cells tissue engineering chitosan-alginate gel

以项目设计为主线的“环境工程设计基础”教学改革探索

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教育教学论坛 2024年第14期 57-60页

作者：田凯勋张俊丰黄妍沈健湘潭大学环境与资源学院湖南湘潭411105

针对现阶段“环境工程设计基础”课程教学过程中的问题,提出了以项目设计为主线的课程教学改革,在理论课授课过程中开展同步工程设计训练。从工程设计内容设计、教学过程管理、考核和教学效果评价等方面进行了全面介绍,同时也对改革过... 详细信息

针对现阶段“环境工程设计基础”课程教学过程中的问题,提出了以项目设计为主线的课程教学改革,在理论课授课过程中开展同步工程设计训练。从工程设计内容设计、教学过程管理、考核和教学效果评价等方面进行了全面介绍,同时也对改革过程中的不足提出了改进建议。通过教学过程中的同步工程设计训练,获得了良好的改革效果。

关键词：环境工程设计基础教学改革同步项目设计内容安排考核方式

学龄前孤独症谱系障碍共患智力发育障碍儿童智力与孤独症症状的相关性分析

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中国疗养医学 2024年第1期33卷 29-32页

作者：耿健田应楷郑裕孙爱梅遵义医投康复医院儿童康复科贵州遵义563000

目的探讨0~6岁学龄前孤独症谱系障碍(ASD)共患智力发育障碍(IDD)儿童神经心理发育量表与儿童孤独症评定量表(CARS)评分的相关性。方法回顾性收集遵义医投康复医院儿童康复科门诊2021年3月至2023年4月就诊并诊断为ASD共患IDD的患儿122例... 详细信息

目的探讨0~6岁学龄前孤独症谱系障碍(ASD)共患智力发育障碍(IDD)儿童神经心理发育量表与儿童孤独症评定量表(CARS)评分的相关性。方法回顾性收集遵义医投康复医院儿童康复科门诊2021年3月至2023年4月就诊并诊断为ASD共患IDD的患儿122例为观察组,另选同期来院诊断为IDD的患儿120例为对照组。采用0~6岁儿童神经心理发育量表评估两组患儿发育商(DQ),采用CARS评估两组患儿的孤独症行为,并采用Pearson相关性分析法分析发育商与孤独症行为分数的关系,采用Kendall相关性分析法分析其智力水平分级与孤独症病情分级的关系。对观察组有统计学意义的因素进行多因素线性回归分析。结果对照组DQ与CARS分数无相关性(r=-0.156,P=0.089)。观察组DQ与CARS分数呈负相关(r=-0.423,P<0.001);观察组大运动及精细动作DQ与CARS分数无相关性(r=0.172,P=0.058;r=0.071,P=0.439),适应能力、语言及社交行为DQ与CARS分数呈负相关(r=-0.532,P<0.001;r=-0.546,P<0.001;r=-0.613,P<0.001);观察组智力水平分级与孤独症病情分级呈负相关(r=-0.243,P<0.05)。多因素线性回归分析显示,适应能力、语言、社交行为和DQ总分是影响孤独症儿童CARS分数的相关因素(P<0.05)。结论学龄前ASD共患IDD患儿其适应能力、语言、社交行为及总发育商与孤独症行为评分关系密切,且其智力落后程度与孤独症病情程度呈负相关。

关键词：学龄前孤独症谱系障碍智力发育障碍 0~6岁儿童神经心理发育量表儿童孤独症评定量表

Investigation into the thermal effect of the LIPS-200 ion thruster plume

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Plasma Science and Technology 2022年第7期24卷 23-34页

作者： Xinwei CHEN Bijiao HE Zuo GU Hai GENG Ning GUO Yong ZHAO kai SHI kai tian Tao CHEN Yifan MA Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of PhysicsLanzhou 730000People's Republic of China School of Astronautics Beihang UniversityBeijing 100191People's Republic of China

The distribution of the thermal effects of the ion thruster plume are essential for estimating the influence of the thruster plume, improving the layout of the spacecraft, and for the thermal shielding of critical sensitive components. In order to obtain the heat flow distribution in the plume of the LIPS-200 xenon ion thruster, an experimental study of the thermal effects of the plume has been conducted in this work,with a total heat flow sensor and a radiant heat flow sensor over an axial distance of 0.5–0.9 m and a thruster angle of 0°–60°. Combined with a Faraday probe and a retarding potential analyzer, the thermal accommodation coefficient of the sensor surface in the plume is available. The results of the experiment show that the xenon ion thruster plume heat flow is mainly concentrated within a range of15°. The total and radial heat flow of the plume downstream of the thruster gradually decreases along the axial and radial directions, with the corresponding values of 11.78 k W m^(-2) and 0.3 k W m^(-2) for the axial 0.5 m position, respectively. At the same position, the radiation heat flow accounts for a very small part of the total heat flow, approximately 3%–5%. The thermal accommodation factor is0.72–0.99 over the measured region. Furthermore, the PIC and DSMC methods based on the Maxwell thermal accommodation coefficient model(EX-PWS) show a maximum error of 28.6% between simulation and experiment for LIPS-200 ion thruster plume heat flow, which, on the one hand, provides an experimental basis for studying the interaction between the ion thruster and the spacecraft, and on the other hand provides optimization of the ion thruster plume simulation model.

关键词： LIPS-200 ion thruster plume thermal effects thermal accommodation factor PIC-DSMC

Synergistic effect from coaxially integrated CNTs@MoS_(2)/MoO_(2) composite enables fast and stable lithium storage

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Journal of Energy Chemistry 2021年第4期30卷 449-458页

作者： Hui Lu kai tian Liangmin Bu Xue Huang Xiangyi Li Yue Zhao Feng Wang Jianming Bai Lijun Gao Jianqing Zhao College of Energy Soochow Institute for Energy and Materials InnovationSSoochow UniversitySuzhou 215006JiangsuChina Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province Soochow UniversitySuzhou 215006JiangsuChina Sustainable Energy Technologies Department Brookhaven National LaboratoryUpton 11973NYUnited States National Synchrotron Light Source II Brookhaven National LaboratoryUpton 11973NYUnited States

Molybdenum oxide/sulfide materials are extensively evaluated as high-capacity anode candidates for lithium ion ***,they suffer from rapid capacity decay and poor ***,we report on synergistic effect from structurally integrated coaxial CNTs@MoS_(2)/MoO_(2) composite material on lithium storage,in which MoS_(2)/MoO_(2) nanosheets are conformally decorated on carbon nanotubes(CNTs).In-situ synchrotron X-ray diffraction measurement is performed to elucidate synergistic effect among three MoS_(2),MoO_(2) and CNTs components for lithium *** mechanism exploration reveals that the MoO_(2) component undergoes reversible Li^(+)intercalation via forming a stable Li_(0.98) MoO_(2) phase over a voltage range of 3.0 to 0.01 V ***^(+)/Li,without experiencing the conversion reaction into metallic Mo,which contributes to long-term stability during charge/discharge ***,lithium storage of MoS_(2) is through lithium and sulfur reversible reaction after the initial conversion reaction of lithiated MoS_(2) forming Li_(2)S and *** CNTs component enhances electronic conductivity and structural stability by minimizing volume change and reaction strains in the CNTs@MoS_(2)/MoO_(2) composite anode.A desired 68.2%capacity retention upon 2000 cycles at 10 A/g has been demonstrated for the CNTs@MoS_(2)/MoO_(2) anode,revealing prominent reaction kinetics and structural stability for fast and stable lithium storage,superior to various Mo-based anode materials previously *** findings from this study,with the unique insight into the role of structural integrity in combining MoS_(2)/MoO_(2) materials with the CNTs substrate,offers a strategy for designing composite anode materials for superior lithium storage performance.

关键词： MoS_(2)/MoO_(2) CNTs Synergistic effect Anode material Lithium storage

Protective benefit of folded linear HDPE board sand fences along the Golmud-Korla Railway,China:Field observation and wind tunnel study

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Journal of Mountain Science 2024年第7期21卷 2206-2219页

作者： ZHANG kai tian Jianjin WANG Zhenghui ZHANG Hailong ZHANG Xingxin College of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730000China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Civil Engineering Chongqing UniversityChongqing 400045China

The Milan Gobi area of the Golmud-Korla Railway in northwest China is located in the lower dispersal area of the mountain pass and has strong winds with evident double wind direction *** study introduced a novel sand fence deployment technique,termed‘folded linear deployment',designed to position the sand fence orthogonally to the two predominant wind directions for optimal *** study used wind tunnel and field tests to evaluate the wind and sand flow characteristics,as well as the windproof and sandresistant performance of folded linear HDPE(Highdensity polyethylene)board sand *** results suggest that the airflow around the fence creates clear zoning *** deceleration area on the BSF(backwind side of the sand fence)is much larger than that on the DSF(downwind side of the sand fence).Thus,sand particles are primarily deposited on the *** different wind speeds,the airflow at 2 and 5 h on the DSF is not *** WSP(wind speed profile)presents a logarithmic *** airflow is disturbed at 1-20 h on the BSF,and the WSP gradually deviates from the logarithmic ***,as the airflow moves away from the fence,the WSP gradually approaches a logarithmic ***,the WPE(windproof efficiency)and SRE(sand-resistant efficiency)of the sand fence exceed 80%.In addition,the results of wind tunnel tests are compared with those of field *** overall dispersion is good,and the best dispersion is found at z/H=2.00,indicating good agreement between the two test *** study provides a scientific basis for the design of sand hazard control measures,similar to the railway project in the Gobi Gale area.

关键词： Folded linear HDPE board sand fence Double wind direction Gobi area Protection benefit