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Chinese Journal of Structural Chemistry 2006年第6期25卷 673-676页

作者： xu Liang-Zhong SHANG yu-qing yu Guan-Ping LI Kai SI Guo-Dong College of Chemistry and Molecular Engineering Qingdao University of Science and Technology Qingdao 266042 China

The title compound 5-[（1H-1,2,4-triazol-1-yl）methyl]-4-（2,3-dimethoxy-benzylideneamino）- 2H-1,2,4-triazole-3（4H）-thione monohydrate 4 has been synthesized by the treatment of 4-amino-3-（ 1,2,4-triazol- 1-yl）- 1 H- 1,2,4-triazole-5（4H）-thione 3 with 2,3-dimethoxybenzaldehyde. It crystallizes as a monohydrate in the triclinic system, space group P1^- with a = 8.147（2）, b = 10.820（2）, c = 10.835（2）A, α= 73.770（6）, β = 84.916（7）,γ = 70.679（6）°, C14H17N7O35, Mr = 363.41, V= 865.4（2）A^3, Z= 2, Dc = 1.395 g/cm^3, F（000） = 380, μ = 0.217 mm^-1, the final R = 0.0400 and wR = 0.0975 for 3454 unique reflections. The dihedral angles made by the thione-substituted triazole ring with the other triazole ring and benzene ring are 74.92（3） and 14.81（2）°, respectively. There are some weak hydrogen bonds and C-H..π supramolecular interactions in the lattice, forming a three-dimensional network, which stabilizes the crystal structure.

关键词： 1,2,4-triazole crystal structure synthesis

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“人造肌肉”收缩性能的实验探究

物理实验 2016年第7期36卷 23-27,31页

作者：孙宇伽周凯车广顺龚佳敏于雪晴孙迎春东北师范大学物理学院吉林长春130024

利用尼龙鱼线丝制作了8种不同参量的"人造肌肉",实验探究了尼龙丝直径、制作时负载、加热温度等条件对"人造肌肉"收缩率的影响,并从理论上解释了"人造肌肉"加热收缩的原因.实验结果表明:温度一定时,选用的鱼线直径越粗,肌肉加热收缩率越... 详细信息

利用尼龙鱼线丝制作了8种不同参量的"人造肌肉",实验探究了尼龙丝直径、制作时负载、加热温度等条件对"人造肌肉"收缩率的影响,并从理论上解释了"人造肌肉"加热收缩的原因.实验结果表明:温度一定时,选用的鱼线直径越粗,肌肉加热收缩率越大;选用材料一定时,存在最优负载使得肌肉收缩率最大.理论说明在温度升高时,体系的熵增大,导致外力作用减小,使得系统的伸长量减小,体系收缩.

关键词：尼龙丝人造肌肉收缩 IYPT

Decorating Covalent Organic Frameworks with High-density Chelate Groups for Uranium Extraction

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Chemical Research in Chinese Universities 2022年第2期38卷 433-439页

作者： QIN xudong TANG Xiaohui MA yu xu Hong xu qing YANG Weiting GU Cheng State Key Laboratory of Luminescent Materials and Devices Institute of Polymer Optoelectronic Materials and DevicesSouth China University of TechnologyGuangzhou 510640P.R.China Key Laboratory of Advanced Materials of Tropical Island Resources Ministry of EductionSchool of Chemical Engineering and TechnologyHainan UniversityHaikou 570228P.R.China CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research Institute(SARI)Chinese Academy of Sciences(CAS)Shanghai 201210P.R.China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084P.R.China Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates South China University of TechnologyGuangzhou 510640P.R.China

The extraction of uranium from aqueous solution is highly desirable for sustaining the increasing demand for environmental safety and nuclear ***,we report a strategy using a two-step covalent modification for the synthesis of covalent organic frameworks(COFs)with high-density amidoxime chelate groups at *** introduction of dense amidoxime groups plays a pivotal role in uranium *** resulting COF exhibits strong affinity with the distribution coefficient of 5.2×104 mL/g and a high adsorption capacity of 319.9 mg/*** strategy could be expanded to identify and remove different contaminants by introducing special functional groups.

关键词： Two-step post-synthetic modification High-density amidoxime Uranium adsorption

Experimental study of the dynamics of a single cavitation bubble excited by a focused laser near the boundary of a rigid wall

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Journal of Hydrodynamics 2023年第5期35卷 942-953页

作者： Xiang-qing Zhang Xiao-fei Zhang xu Qiu Dan Gao yu-ning Zhang Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China China Atomic Energy Publishing and Media Co.LTD Beijing100048China China Institute of Nuclear Industry Strategy Beijing100048China National Institute of Energy Development Strategy North China Electric Power UniversityBeijing102206China

Based on high-speed photographic experiments,this study presents a detailed qualitative and quantitative analysis of the dynamics of a single cavitation bubble near the boundary of a rigid wall in asymmetric *** main findings are reported as follows:(1)The non-sphericity of the bubble interface decreases with increasing spacing between the bubble and the boundary,and the asymmetry of the bubble becomes more significant with increasing asymmetry angle.(2)The motion mode of the bubble cluster in the second oscillation cycle can be divided into two typical modes depending on the direction of movement.(3)The angle between the oblique jet pointing towards the upper wall surface and the horizontal direction in the second oscillation cycle decreases as the dimensionless spacing decreases.

关键词： Asymmetry boundary cavitation bubble high-speed photography jet non-sphericity

Novel Metal-organic Framework Compound Pb(C_5H_4NCOO)_2 Showing One-dimensional Channel Defined as Four Leads and Four Nicotinic Acids

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Chemical Research in Chinese Universities 2009年第3期25卷 279-281页

作者： xu Xiao-yu ZHOU Rui-sha SONG Jiang-feng xu Ji-qing College of Chemistry and State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changchun 130012 P. R. China

A novel metal-organic framework（MOF） compound of Pb（C5H4NCOO）2 was hydrothermally synthesized and structurally determined by X-ray single-crystal diffraction. The data of unit cell： orthorhombic space group Pccn, a=1.0325（2） nm, b=1.3597（3） nm, c=0.8499（2） nm, V=1.1931（4） nm^3, Z=4, Dc=2.513 g/cm^3, R1=0.047 were obtained on the basis of 1365 reflections with Fo〉2σ（Fo）. PbN2O6 polyhedron adopts the distorted cubic configuration which is assigned to the holodirected geometry. These PbN2O6 polyhedra can form the zigzag chain by edge-sharing mode along（001） direction. Pb atom is connected by six nicotinic acid molecules, leading neutral 3D metal-organic framework with a channel defined by four Pb atoms and four nicotinic acid molecules.

关键词： Metal-organic framework(MOF) Lead Holodirected structure

Numerical Simulation of Icing on Nrel 5-MW Reference Offshore Wind Turbine Blades Under Different Icing Conditions

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China Ocean Engineering 2022年第5期36卷 767-780页

作者： CAO Hui-qing BAI xu MA Xian-dong YIN Qun YANG Xiang-yu School of Naval Architecture&Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China The Department of Engineering Lancaster UniversityLancaster LA14YWUK

Offshore wind energy resources are operational in cold regions,while offshore wind turbines will face the threat of ***,it is necessary to study icing of offshore wind turbines under different icing *** this study,icing sensitivity of offshore wind turbine blades are performed using a combination of FLUENT and FENSAP-ICE software,and the effects of liquid water content(LWC),medium volume diameter(MVD),wind speed and air temperature on blade icing shape are analyzed by two types of ice,namely rime ice and glaze *** results show that the increase of LWC and MVD will increase the amount of ice that forms on the blade surface for either glaze ice or rime ice,and an increase of MVD will expand the adhesion surface between ice and *** reaching the rated wind speed of 11.4 m/s,it does not directly affect the icing ***,after reaching the rated wind speed,the attack angle of the incoming flow decreases obviously,and the amount of ice increases *** the ambient air temperature meets the icing conditions of glaze ice(i.e.,−5℃ to 0℃),the lower the temperature,the more glaze ice freezes,whereas air temperature has no impact on the icing of rime *** with onshore wind turbines,offshore wind turbines might face extreme meteorological conditions,and the wind speed has no impact on the amount of ice that forms on the blade surface for most wind speeds.

关键词： environmental parameters cold regions offshore wind turbine rime glaze numerical simulation

Effect of gradient temperature rolling process on promoting crack healing in Q500 heavy plates

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 354-361页

作者： Zhao-hai Gao Wei yu xu Chen Bao-sheng Xie qing-wu Cai Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China National Engineering Research Center of Advanced Rolling University of Science and Technology BeijingBeijing 100083China Hunan Valin Rolling Steel Sheet Co.Ltd LoudiHunan 417000China

To ensure the quality of heavy plate products as determined by ultrasonic inspection, it is necessary to effectively control defects such as cracks and shrinkage cavities in heavy plates. Generally, some defects such as large size cracks exist due to insufficient deformation in the center of traditionally rolled plates. Compared with the traditional rolling process, gradient temperature rolling(GTR) process can effectively increase deformation inside heavy plates. In this study, the effect of GTR on crack healing was analyzed through a comparison experiment with the uniform temperature rolling(UTR). The results show that the GTR process could increase the plastic strain inside the heavy plate and effectively promote the healing process of the preset cracks. The degrees of crack healing at the center and quarter thickness position of the steel plate via GTR were greater than twice those of the plate via UTR. The GTR process can significantly reduce the internal defects of heavy plates and improve the defect detection level of heavy plate products. Also, The GTR process results in the formation of new crystal grains in the crack region, which is crucial to crack healing.

关键词： heavy plates multilayer pack rolling crack healing behavior hot rolling process

Analysis of morphological characteristics of gravels based on digital image processing technology and self-organizing map

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Journal of Arid Land 2023年第3期15卷 310-326页

作者： xu Tao yu Huan QIU Xia KONG Bo XIANG qing xu Xiaoyu FU Hao College of Earth Science Chengdu University of TechnologyChengdu 610059China Beijing SuperMap Software Co. Ltd.Beijing 100015China Sichuan Real Estate Registration Center Chengdu 610014China Chengdu Institute of Mountain Land and Disasters Chinese Academy of SciencesChengdu 610041China School of Earth Systems and Sustainability Southern Illinois University CarbondaleCarbondaleIL 62901United States of America Environmental Resources and Policy Southern Illinois University CarbondaleCarbondaleIL 62901United States of America Sichuan Institute of Land and Space Ecological Restoration and Geohazard Prevention Chengdu 610081China

A comprehensive understanding of spatial distribution and clustering patterns of gravels is of great significance for ecological restoration and ***,traditional methods for studying gravels are low-efficiency and have many *** study researched the spatial distribution and cluster characteristics of gravels based on digital image processing technology combined with a self-organizing map(SOM)and multivariate statistical methods in the grassland of northern Tibetan ***,the correlation of morphological parameters of gravels between different cluster groups and the environmental factors affecting gravel distribution were *** results showed that the morphological characteristics of gravels in northern region(cluster C)and southern region(cluster B)of the Tibetan Plateau were similar,with a low gravel coverage,small gravel diameter,and elongated *** regions were mainly distributed in high mountainous areas with large topographic *** central region(cluster A)has high coverage of gravels with a larger diameter,mainly distributed in high-altitude plains with smaller *** component analysis(PCA)results showed that the gravel distribution of cluster A may be mainly affected by vegetation,while those in clusters B and C could be mainly affected by topography,climate,and *** study confirmed that the combination of digital image processing technology and SOM could effectively analyzed the spatial distribution characteristics of gravels,providing a new mode for gravel research.

关键词： self-organizing map digital image processing morphological characteristics multivariate statistical method environmental monitoring

The Effect of Error Growth and Propagation on the Predictability of Quantitative Precipitation in a Cloud-Resolving Model

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Atmospheric and Oceanic Science Letters 2009年第2期2卷 79-84页

作者： xu Jian-yu ZHONG qing Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Limitations in the predictability of quantitative precipitation forecasting (QPF) that arise from initial errors of small amplitude and scale are investigated by means of real-case high-resolution (cloud-resolving) numerical weather prediction (NWP) integrations. The case considered is the hail and wind disaster that occurred in Sichuan on 8 April 2005. A total of three distinct perturbation methods are used. The results suggest that a tiny initial error in the temperature field can amplify and influence the weather in a large domain, changing the 12-h forecasted rainfall by as much as one-third of the original magnitude. Furthermore, the comparison of the perturbation methods indicates that all of the methods pinpoint the same region (the heavy rainfall areas in the control experiment) as suffering from limitations in predictability. This result reveals the important role of nonlinearity in severe convective events.

关键词： error quantitative precipitation predictability

Ta-W/Hf合金的结构稳定性及力学性质的第一性原理计算

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原子与分子物理学报 2025年第1期42卷 135-144页

作者：周少兰李忠盛丛大龙韦禹詹青青赵子鹏冉旭东西南技术工程研究所重庆400039

Ta-W/Hf合金具有高熔点、高密度、高延展性等性质,在核电、武器装备等关键零部件中发挥着重要作用,本研究基于密度泛函理论的第一性原理方法,构建不同掺杂含量下的Ta-W/Hf合金模型,计算Ta-W/Hf的晶格常数、结合能、弹性常数、弹性模量... 详细信息

Ta-W/Hf合金具有高熔点、高密度、高延展性等性质,在核电、武器装备等关键零部件中发挥着重要作用,本研究基于密度泛函理论的第一性原理方法,构建不同掺杂含量下的Ta-W/Hf合金模型,计算Ta-W/Hf的晶格常数、结合能、弹性常数、弹性模量、泊松比、维氏硬度、电子态密度等性质参数,分析W、Hf掺杂元素对Ta合金稳定性及力学性能的影响.结果表明:Ta-W合金的晶格常数、弹性常数、体模量、杨氏模量、剪切模量均随着W含量的增加而增加;然而Ta-Hf合金的相关性质参数变化趋势则相反.同时,结合能及电子态密度结果表明Ta-W合金的稳定性与W含量呈正相关;Ta-Hf合金的稳定性随着Hf含量的增加而降低,但Hf的添加对Ta合金的各向异性趋势变化影响显著,且Hf可以明显提高Ta合金的韧性.

关键词： Ta-W/Hf合金第一性原理结构稳定力学性质

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