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Long-Term Settlement Characterization of High-Filling Foundation in the Mountain Excavation and City Construction Area of the Yan’an New District,China

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Journal of Earth Science 2023年第6期34卷 1908-1915页

作者： Xiaokun hou Shengwen Qi Yongtang Yu Jianguo Zheng Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Sciences Chinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China China United Northwest Institute for Engineering Design&Research Co. Ltd.Xi'an 710077China China Jikan Research Institute of Engineering Investigations and Design Co. Ltd.Xi'an 710021China

Mountain Excavation and City Construction(MECC)represents a prominent anthropogenic endeavor aimed at facilitating urban expansion in the Loess Plateau of *** is important to comprehend the long-term settlement behavior at MECC engineering sites to effectively assess the project’s success in reshaping landscapes and expanding urban *** this study,a typical MECC project,specifically the upstream area of the Liujiagou Valley within the new district of Yan’an City,is selected as a case study to investigate long-term settlement *** research involved conducting creep tests on soil samples with varying dry densities and moisture content and continuous in-situ monitoring of ground surface settlement at 17 specific ***,a numerical model was developed and calibrated using the in-situ monitoring data to predict the long-term *** findings reveal that an increase in soil dry density and a decrease in soil water content contribute to reduced ***,settlement primarily manifests within the filled areas,with greater soil thickness exacerbating settlement *** time,cumulative settlement exhibits a progressively diminishing rate of deformation until it attains a stable *** results provide insights for assessing the long-term stability of MECC projects,facilitating decision-making in future endeavors within this region.

关键词： Loess Plateau of China long-term settlement in-situ observation numerical analysis engineering geology

孕妇妊娠早期血清25-羟维生素D水平与围生期抑郁及骨密度的关系

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实用妇科内分泌电子杂志 2024年第11期11卷 11-13页

作者：侯爵徐烨黄冬梅佛山市南海区妇幼保健院产科广东佛山528000

目的探讨妊娠早期血清25-羟维生素D水平与围生期抑郁及骨密度的关系。方法选取在本院建档的120例单胎妊娠早期孕妇为研究对象,通过资料收集,采集孕妇静脉血,采用放射免疫法检测血清25-羟维生素D水平,根据血清25-羟维生素D水平将孕妇分... 详细信息

目的探讨妊娠早期血清25-羟维生素D水平与围生期抑郁及骨密度的关系。方法选取在本院建档的120例单胎妊娠早期孕妇为研究对象,通过资料收集,采集孕妇静脉血,采用放射免疫法检测血清25-羟维生素D水平,根据血清25-羟维生素D水平将孕妇分为维生素D正常组、维生素D不足组、维生素D缺乏组和维生素D严重缺乏组,各30例,比较各组的抑郁程度、骨密度水平。结果维生素D正常组血清25-羟维生素D水平、T-Score指标均高于维生素D不足组、维生素D缺乏组、维生素D严重缺乏组,爱丁堡产后抑郁量表评分低于维生素D不足组、维生素D缺乏组、维生素D严重缺乏组,差异有统计学意义(P<0.05);Pearson相关分析显示,妊娠早期孕妇血清25-羟维生素D水平与抑郁、骨密度呈显著正相关(r=0.273、r=0.726,P<0.05)。结论妊娠早期血清25-羟维生素D水平与围生期抑郁及骨密度有直接影响,由此注重妊娠早期血清25-羟维生素D水平变化,可能减少围生期抑郁及骨质疏松症的发生。

关键词：妊娠早期血清25-羟维生素D 围生期抑郁骨密度

Effects of Time Delay on Multistability of Genetic Toggle Switch

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Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： De-qing Zhu Hui-jun Jiang Zhong-huai hou Department of Chemical Physics & Hefei National Laboratory for Physical Sciences at the Microscales iChEM University of Science and Technology of China Hefei 230026 China

The effect of time delay on a genetic toggle switch, whose undelayed dynamics shows low protein expression states (L-states), high expression states (H-states) and coexistence of them different transcription-factor binding rates α, is investigated by using the delayed stochastic simulation method. Interestingly, we find that the delay induces a transition from the coexistence state to L-state or H-state by suppressing the other state. Moreover, the phase diagram on the α-τ plane is obtained by extensive simulations. It is observed that, the coexistence state is remarkably narrowed by increasing delay time, and completely disappears above a triple-point-like point where direct transitions between H-state and L-state are possible.

关键词： Genetic toggle switch Delay Multistability

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电子信息工程的实验教学分析

集成电路应用 2024年第2期41卷 154-155页

作者：王新刚侯宁魏怡河南城建学院电气与控制工程学院河南467000

阐述电子信息工程专业实验室建设现状,提出电子信息工程专业实验室建设策略,包括加强实验室基础设备建设、完善实验管理、健全实验室管理机制,从而促进科研进步与发展。

关键词：电子信息工程实验教学基础设备

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探地雷达在路基压实质量检测中的应用

天津建设科技 2024年第4期34卷 45-48页

作者：赵琦顿长朋侯子义天津市交通运输基础设施养护集团有限公司天津300201 河北工业大学土木与交通学院天津300401

为了快速准确地检测路基的压实质量,采用探地雷达对路基土的密度进行无破损连续检测。在振动压路机碾压不同遍数后,采用探地雷达在长度方向测试土的电物理性质,测定相对介电常数的模与土密度的关系,可以看出在路基碾压施工过程中相对介... 详细信息

为了快速准确地检测路基的压实质量,采用探地雷达对路基土的密度进行无破损连续检测。在振动压路机碾压不同遍数后,采用探地雷达在长度方向测试土的电物理性质,测定相对介电常数的模与土密度的关系,可以看出在路基碾压施工过程中相对介电常数增加。根据相对介电常数与压路机碾压遍数的关系,在碾压过程中,可以在雷达图上精确标出固定土层厚度的位置。根据固定厚度的土层反射率和密度与压路机碾压遍数的关系,可以确定土层反射率,确定土层的密度。

关键词：路基压实质量探地雷达土的密度

Effects of Surface State and Applied Stress on Stress Corrosion Cracking of Alloy 690TT in Lead-containing Caustic Solution

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Journal of Materials Science & Technology 2012年第9期28卷 785-792页

作者： Zhiming Zhang Jianqiu Wang En-hou Han Wei Ke State Key Laboratory for Corrosion and Protection Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The effects of surface state and applied stress on the stress corrosion cracking （SCC） behaviors of thermally treated （TT） Alloy 690 in 10 wt% NaOH solution with 100 mg/L litharge at 330 ℃ were investigated using C-ring samples with four kinds of surface states and two different stress levels. Sample outer surfaces of the first three kinds were ground to 400 grit （ground）, shot-peened （SP） and electro-polished （EP） and the last one was used as the as-received state. Two samples of every kind were stressed to 100% and 200% yield stress of Alloy 690TT, respectively. The results showed that the oxide film consisted of three layers whereas continuous layer rich in Cr was not found. The poor adhesive ability indicated that the oxide film could not protect the matrix from further corrosion. Lead was found in the oxide film and the oxides at the crack paths and accelerated the dissolution of thermodynamically unstable Cr in these locations and also in the matrix. The crack initiation and propagation on Alloy 690TT were effectively retarded by SP and EP treatments but were enhanced by grinding treatment, compared with the cracks on the as-received surface. The cracking severity was also enhanced by increasing the externally applied stress. The accelerated dissolution of Cr and the local tensile stress concentration in the near-surface layer caused by cold-working and higher applied stress reduced the SCC-resistance of Alloy 690TT in the studied solution.

关键词： Alloy 690TT Surface state Applied stress Stress corrosion cracking

ARTIFICIAL BOUNDARY METHOD FOR BURGERS＇ EQUATION USING NONLINEAR BOUNDARY CONDITIONS

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Journal of Computational Mathematics 2006年第3期24卷 295-304页

作者： hou-de Han Xiao-nan Wu Zhen-li Xu Department of Mathematical Sciences Tsinghua University Beijing 100084. China Department of Mathematics Hong Kong Baptist University Kowloon Tong Hong Kong Department of Mathematics University of Science and Technology of China Hefei 230026 China

This paper discusses the numerical solution of Burgers＇ equation on unbounded domains. Two artificial boundaries are introduced and boundary conditions are obtained on the artificial boundaries, which are in nonlinear forms. Then the original problem is reduced to an equivalent problem on a bounded domain. Finite difference method is applied to the reduced problem, and some numerical examples are given to show the effectiveness of the new approach.

关键词： Burgers' equation Unbounded domain Artificial boundary condition.

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浅析低温仪表开关阀的特殊要求

石油化工自动化 2024年第4期60卷 32-35+70页

作者：皮宇侯长江李本江中石化广州工程有限公司中石油云南石化有限公司富海集团新能源控股有限公司

低温仪表开关阀因为工作在极为苛刻的低温环境，在阀门的制造及设计过程有很多特殊的要求以保证低温下的功能，例如阀座和壳体的泄漏等级等。从阀型的选择、阀门安装类型、球阀设计、蝶阀结构等方面，分析了低温阀门专用的设计和制造标... 详细信息

低温仪表开关阀因为工作在极为苛刻的低温环境，在阀门的制造及设计过程有很多特殊的要求以保证低温下的功能，例如阀座和壳体的泄漏等级等。从阀型的选择、阀门安装类型、球阀设计、蝶阀结构等方面，分析了低温阀门专用的设计和制造标准以及特殊要求。介绍了阀体、内件及其材质、阀盖及填料、低温测试、防火等方面的特殊要求。对比分析了国外LNG项目低温阀门的特殊要求和国内低温阀门厂家的制造技术特点，以期提高国产阀门的质量，促进国产化的进程。

关键词：低温阀门专用标准阀体及内件阀盖及填料低温测试防火国产化

烟盲蝽对不同虫态烟粉虱的捕食作用及捕食偏好性

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环境昆虫学报 2024年第3期46卷 737-743页

作者：曹璐侯启华刘树生刘银泉浙江大学昆虫科学研究所浙江省作物病虫生物学重点实验室农业农村部作物病虫分子生物学重点实验室杭州310058

杂食性昆虫烟盲蝽Nesidiocoris tenuis是烟粉虱Bemisia tabaci的重要天敌之一。为探索烟盲蝽对不同虫态烟粉虱的捕食作用及捕食偏好性,在室内进行了非选择性和选择性试验。结果表明,在非选择性试验中,烟盲蝽雌成虫、雄成虫以及5龄若虫... 详细信息

杂食性昆虫烟盲蝽Nesidiocoris tenuis是烟粉虱Bemisia tabaci的重要天敌之一。为探索烟盲蝽对不同虫态烟粉虱的捕食作用及捕食偏好性,在室内进行了非选择性和选择性试验。结果表明,在非选择性试验中,烟盲蝽雌成虫、雄成虫以及5龄若虫可以捕食烟粉虱成虫和各龄若虫,但极少捕食卵。其中,烟盲蝽雌成虫、雄成虫及5龄若虫对烟粉虱1龄若虫的捕食量最大,分别为134.2头、101.3头和88.1头,其次是2~3龄若虫,捕食量分别为94.1头、64.2头和53.4头。而在选择性试验中烟盲蝽雄虫更偏好捕食烟粉虱的2~3龄若虫,其次是1龄若虫、4龄若虫和成虫。该结果对了解烟盲蝽控制烟粉虱的作用以及如何对烟盲蝽和其他天敌组合应用提供了参考信息。

关键词：烟盲蝽烟粉虱捕食偏好性 Cain指数生物防治