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四川茂县新磨村高位滑坡铲刮作用分析

水文地质工程地质 2019年第3期46卷 138-145页

作者：张涛杨志华张永双陈亮吴瑞安中国地质科学院地质力学研究所北京100081 中国地质调查局天津地质调查中心天津300170 四川省地质调查院四川成都610081

2.17年6月2.日,四川省茂县叠溪镇新磨村发生高位顺层山体滑坡,滑动高差达1 160 m,滑动平距约2.2.0 m。该滑坡的滑动方量巨大,与其滑动过程中产生的铲刮效应有关。为分析其铲刮效应,文章通过现场调查、遥感影像解译和无人机航拍图像,确... 详细信息

2.17年6月2.日,四川省茂县叠溪镇新磨村发生高位顺层山体滑坡,滑动高差达1 160 m,滑动平距约2.2.0 m。该滑坡的滑动方量巨大,与其滑动过程中产生的铲刮效应有关。为分析其铲刮效应,文章通过现场调查、遥感影像解译和无人机航拍图像,确定该滑坡的滑动全过程为:多次历史地震造成滑坡源区岩体结构破碎,降雨沿顶部裂隙入渗导致水压力增大及石英砂岩中的薄层板岩软化,在长期疲劳效应下斜坡上部岩体最终发生滑动;上部滑体在运移过程中,对斜坡中部浅表风化层、部分基岩及下部老滑坡堆积体进行铲刮并重新堆积。采用Rockfall软件模拟源区滑体的运动路径、速度与能量,结果表明:在碎屑流区和老滑坡堆积区都存在明显的集中铲刮作用,整个滑坡的高危险区也主要位于该区域,所以危险性分区可代表不同滑坡区域的铲刮程度。计算得两个区域的铲刮方量分别为4. 9×10~6,4. 3.×10~6m^3.滑坡总方量为13. 3.×10~6m^3.该模拟和计算方法迅速有效,可为以后类似滑坡的应急、救灾和铲刮方量计算提供参考。

关键词：高位滑坡滑坡-碎屑流新磨村滑坡铲刮效应 Rockfall模拟

基于聚类分析的绿色背景迷彩服近红外伪装效果评价方法

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北京服装学院学报（自然科学版） 2019年第2期39卷 38-42页

作者：杨星周永凯张华北京服装学院北京100029 军事科学院系统工程研究院军需工程技术研究所北京100010

为了探求一个可行的评价迷彩服近红外伪装效果的方法,以绿色背景为例,测定了10种绿色植物在波长范围3.0 nm^1 2.0 nm的反射率并制得反射光谱;引入聚类分析的方法对测得的反射光谱数据进行分析,以不同植物作为变量,对波长进行系统聚类,... 详细信息

为了探求一个可行的评价迷彩服近红外伪装效果的方法,以绿色背景为例,测定了10种绿色植物在波长范围3.0 nm^1 2.0 nm的反射率并制得反射光谱;引入聚类分析的方法对测得的反射光谱数据进行分析,以不同植物作为变量,对波长进行系统聚类,得到光谱特征在不同类别波段上的分布;在不同波段上拟合曲线制定相应的光谱范围用来评价迷彩服的近红外伪装效果,并对2.迷彩服进行了评价。结果表明:本文的评价方法可以对迷彩服反射光谱符合绿色植被的程度进行有效而准确的评价,同时整个评价过程较为明确可行,为其他类型背景的迷彩服评价提供一个合理的参考。

关键词：反射光谱近红外伪装聚类分析

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多重激励下机匣振动能量传递规律与耦合特性

推进技术 2019年第6期40卷 1389-1398页

作者：马英群张锴徐蒙赵巍赵庆军中国科学院工程热物理研究所北京100190 中国科学院大学航空宇航学院北京100049 中国科学院轻型动力重点实验室北京100190

为了研究机匣振动能量的传递规律和转子多重不平衡激励能量在机匣上的耦合特性,采用有限元法建立了包括压气机机匣、燃烧室机匣和涡轮机匣组件在内的航空发动机整机机匣模型,应用结构声强法计算分析了机匣在不同激励频率下振动能量的传... 详细信息

为了研究机匣振动能量的传递规律和转子多重不平衡激励能量在机匣上的耦合特性,采用有限元法建立了包括压气机机匣、燃烧室机匣和涡轮机匣组件在内的航空发动机整机机匣模型,应用结构声强法计算分析了机匣在不同激励频率下振动能量的传递规律和耦合特性。结果表明:(1)机匣共振时,振动能量的穿透力最强,主要以纵波和剪切波的形式穿过机匣安装边向其他部件传递。(2.机匣的模态振型与其振动能量传递特性有关,振动幅值较大的机匣组件同时也是主要参与振动能量传递的机匣组件。(3.振动能量在机匣上的传递具有解耦特性,多重激励同时作用下的机匣振动能量传递特性可以分解为多个单一激励作用下机匣振动能量的线性矢量和。

关键词：整机机匣结构声强法振动功率流振动能量传递规律振动能量耦合特性

Assessment of organic compost and biochar in promoting phytoremediation of crude-oil contaminated soil using Calendula officinalis in the Loess Plateau, china

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Journal of Arid Land 2021年第6期13卷 612-628页

作者： WANG Jincheng JING Mingbo zhang Wei zhang Gaosen zhang Binglin LIU Guangxiu CHEN Tuo ZHAO Zhiguang key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China key Laboratory of Extreme Environmental Microbial Resources and engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese academy of Sciences Beijing 100049China Gansu key Laboratory of Protection and Utilization for Biological Resources and Ecological Restoration Longdong UniversityQingyang 745000China State key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Life Sciences Lanzhou UniversityLanzhou 730000China

The Loess Plateau,located in Gansu Province,is an important energy base in china because most of the oil and gas resources are distributed in Gansu *** the last 40 a,ecological environment in this region has been extremely destroyed due to the over-exploitation of crude-oil *** of crude-oil contaminated soil in this area remains to be a challenging *** this study,in order to elucidate the effects of organic compost and biochar on phytoremediation of crude-oil contaminated soil(2. g/kg)by Calendula officinalis,we designed five treatments,i.e.,natural attenuation(CK),planted *** only(P),planted *** with biochar amendment(PB),planted *** with organic compost amendment(PC),and planted *** with co-amendment of biochar and organic compost(PBC).After 152.d of cultivation,total petroleum hydrocarbons(TPH)removal rates of CK,P,PB,PC and PBC were 6.3.%,50.08%,3..58%,73.10%and 59.87%,*** and root dry weights of *** significantly increased by 172.3.%and 80.96%under PC and 3.1.61%and 145.43.under PBC,respectively as compared with P(P3.%,12..50%and 79.80%,respectively(P<0.05)as compared with ***-chemical characteristics and enzymatic activity of soil in different treatments were also *** highest total N,total P,available N,available P and SOM(soil organic matter)occurred in PC,followed by PBC(P<0.05).*** rhizospheric soil dehydrogenase(DHA)and polyphenol oxidase(PPO)activities in PB were lower than those of other treatments(P<0.05).The values of ACE(abundance-based coverage estimators)and Chao 1 indices for rhizospheric bacteria were the highest under PC followed by PBC,P,PB and CK(P<0.05).However,the Shannon index for bacteria was the highest under PC and PBC,followed by P,PB and CK(P<0.05).In terms of soil microbial community composition,Proteiniphil

关键词： total petroleum hydrocarbons soil physical-chemical characteristics plant physiological parameters soil enzyme microbial community composition

基于l_1正则化的多通道滑动聚束SAR成像

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系统工程与电子技术 2019年第2期41卷 304-310页

作者：徐志林魏中浩吴辰阳张冰尘中国科学院电子学研究所北京100190 空间信息处理与应用系统技术重点实验室北京100190 中国科学院大学北京100190

提出了基于l_1正则化的多通道滑动聚束合成孔径雷达(synthetic aperture radar,SAR)稀疏成像算法。该方法将偏置相位中心天线(displaced phase center antenna,DPCA)技术和l_1正则化策略结合来解决非均匀采样带来的方位模糊问题,并利用... 详细信息

提出了基于l_1正则化的多通道滑动聚束合成孔径雷达(synthetic aperture radar,SAR)稀疏成像算法。该方法将偏置相位中心天线(displaced phase center antenna,DPCA)技术和l_1正则化策略结合来解决非均匀采样带来的方位模糊问题,并利用方位距离解耦算法降低计算复杂度。当非均匀度较大时,所提方法相比于基于多普勒频谱重建的匹配滤波器组方法能更有效抑制方位模糊,具有更大的距离向测绘带宽潜力。该方法能有效抑制噪声和旁瓣,提高目标背景比,从而提高成像性能。通过仿真和实际数据实验,验证了所提算法的有效性。

关键词：滑动聚束合成孔径雷达多通道偏置相位中心天线 l1正则化

Theoretical and experimental design of Pt-Co（OH）2.electrocatalyst for efficient HER performance in alkaline solution

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Progress in Natural Science:Materials International 2019年第3期29卷 356-361页

作者： Haijun Wu Xiaoqing Zuo Shanpeng Wang Jun-Wen Yin Yan-Ning zhang Jialin Chen School of Materials Science and engineering Kunming University of Science and Technology State key Laboratory of New Technologies for Comprehensive Utilization of Rare and Precious Metals beijing Computational Science Research Center institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China

Design efficient electrocatalysts become significant for the hydrogen evolution reaction （HER） in alkaline ***,the HER performance on Pt-Co（OH）2.has been investigated by using DFT *** with pure Pt,the Pt-Co（OH）2.shows excellent hydrogen binding energy （-0.2. eV） and hydrogen adsorption free energy （0.02.eV）.More strikingly,the water dissociation process on Pt-Co（OH）2.is an exothermic reaction while that of Pt is an endothermic reaction,demonstrating that the Pt-Co（OH）2.s an excellent catalyst for HER in alkaline *** the two-step electrodepositions was used to fabricate Pt-Co（OH）2.on the carbon paper （CP）.The Pt-Co（OH）2.CP shows the lowest overpotential of only 3..6 mV at a current density of 10 mA cm-2.n 0.1M KOH,the smallest Tafel slope of58 mV dec-1and the good stability for 2.000s without obvious degradation.

关键词： OH Theoretical and experimental design of Pt-Co HER electrocatalyst for efficient HER performance in alkaline solution

Temperature-dependent evolution of surface charge screening and polarization at ferroelectric surfaces

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Science china(Physics,Mechanics & Astronomy) 2019年第8期62卷 117-120页

作者： LongFei Wang Yi Luo JieSu Wang XiuShi Huang ZhaoMeng Gao TieYing yang XiaoLong Li Pei Li KuiJuan Jin WeiFeng zhang HaiZhong Guo Henan key Laboratory of Photovoltaic Materials School of Physics and Electronics Henan University School of Physical engineering Zhengzhou University beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Shanghai Synchrotron Radiation Facility (SSRF) Shanghai Institute of Applied Physics Chinese Academy of Sciences

The polarization and domain behavior on the surface of a ferroelectric material are significantly affected by the screening processes [1-12..Recently,there has been a notable increase in the theoretical calculations and experiments investigating the dynamics of polarization and domain behaviors coexisting in phase transitions of ferroelectric materials.

关键词： significantly affected screening processes theoretical calculations

Rambutan-like hierarchically heterostructured CeO2.CuO hollow microspheres： Facile hydrothermal synthesis and applications

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Nano Research 2017年第2期10卷 381-396页

作者： Yongjun Ji Zheying Jin Jing Li Yu zhang Hezhi Liu Laishun Shi Ziyi Zhong Fabing Su State key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing I O0190 China University of Chinese academy of Sciences Beijing 100049 China School of Chemistry and Chemical engineering Shandong University Jinan 250100 China institute of Chemical engineering and Sciences 1 Pesek Road Jurong Island Singapore 627833 Singapore School of Chemical & Biomedical engineering Nanyang Technological University (NTU) 62 Nanyang Drive Singapore 637459 Singapore

Hierarchically heterostructured hollow spheres are of great interest for a wide range of applications owing to their unique structural features and properties. However, the fabrication of well-defined hollow spheres with highly specific morphology for mixed transition metal oxides on a large scale remains challenging. In this work, uniform rambutan-like heterostructured CeO2.CuO hollow microspheres with numerous copper-ceria interfacial sites and nanorods and nanoparticles as building blocks are prepared via a facile hydrothermal method followed by calcination. Importantly, this approach can be readily scaled up and is applicable to the synthesis of various CuO-based mixed metal oxide complex hollow spheres. The as-prepared CeO2.CuO hollow rambutans exhibit superior performance both as electrode materials for supercapacitors and as Cu-based catalysts for the Rochow reaction, mainly due to the small primary nanoparticle constituents, high surface area, and formation of numerous interior heterostructures.

关键词： heterostructure hollow sphere rambutan supercapacitors Rochow reaction

Zr_(2.SeB and Hf_(2.SeB:Two new MAB phase compounds with the Cr_(2.AlC-type MAX phase({3. phase)crystal structures

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Journal of Advanced Ceramics 2022年第11期11卷 1764-1776页

作者： Qiqiang zhang Yanchun ZHOU Xingyuan SAN Wenbo LI Yiwang BAO Qingguo FENG Salvatore GRASSO Chunfeng HU key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China Hebei key Lab of Optic–Electronic Information and Materials College of Physics Science and TechnologyHebei UniversityBaoding 071002China State key Laboratory of Green Building Materials China Building Materials AcademyBeijing 100024China

The ternary or quaternary layered compounds called MAB phases are frequently mentioned recently together with the well-known MAX ***,MAB phases are generally referred to layered transition metal borides,while MAX phases are layered transition metal carbides and nitrides with different types of crystal structure although they share the common nano-laminated structure *** order to prove that MAB phases can share the same type of crystal structure with MAX phases and extend the composition window of MAX phases from carbides and nitrides to borides,two new MAB phase compounds Zr_(2.SeB and Hf_(2.SeB with the Cr_(2.AlC-type MAX phase({3. phase)crystal structure were discovered by a combination of first-principles calculations and experimental verification in this ***-principles calculations predicted the stability and lattice parameters of the two new MAB phase compounds Zr_(2.SeB and Hf_(2.*** they were successfully synthesized by using a thermal explosion method in a spark plasma sintering(SPS)*** crystal structures of Zr_(2.SeB and Hf_(2.SeB were determined by a combination of the X-ray diffraction(XRD),scanning electron microscopy(SEM),and high-resolution transmission electron microscopy(HRTEM).The lattice parameters of Zr_(2.SeB and Hf_(2.SeB are a=3.643.8Å,c=12.63.0}3.and a=3.52.80Å,c=12.47804Å,*** the atomic positions are M at 4f(1/3.2.3.0.602.8[Zr]or 0.59889[Hf]),Se at 2.(1/3.2.3.1/4),and B at 2.(0,0,0).And the atomic stacking sequences follow those of the Cr_(2.AlC-type MAX *** work opens up the composition window for the MAB phases and MAX phases and will trigger the interests of material scientists and physicists to explore new compounds and properties in this new family of materials.

关键词： Zr_(2.SeB and Hf_(2.SeB MAB phase MAX phase first-principles calculations thermal explosion synthesis