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探针有限特性对热脉冲技术测定土壤热特性的影响

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农业工程学报 2014年第19期30卷 71-77页

作者：付永威卢奕丽任图生中国农业大学土壤与水科学系北京100193

在利用热脉冲方法测定热特性时，通常对探针形状做理想化处理，即假设探针为线性热源，热导率无限大而热容量为零。在实际应用中，探针本身的有限特性（有限半径以及有限热容量）会导致热特性测定误差。为了研究探针有限特性对热脉冲技... 详细信息

在利用热脉冲方法测定热特性时，通常对探针形状做理想化处理，即假设探针为线性热源，热导率无限大而热容量为零。在实际应用中，探针本身的有限特性（有限半径以及有限热容量）会导致热特性测定误差。为了研究探针有限特性对热脉冲技术测定土壤热特性的影响，该研究采用改进的热脉冲探针（直径2mm、长度40mm、间距8mm）测定土壤热特性，并分别使用PILS（pulsed infinite line source，无限长线性脉冲热源）和ICPC（identical cylindrical perfect conductors，近似圆柱形完美导体）2种理论估计土壤热特性，比较分析了探针有限特性对热脉冲技术测定热特性结果的影响。结果表明：1）与PILS理论相比，利用ICPC理论拟合得到的温度升高曲线，可以有效减少探针有限半径和热容量对土壤热特性测定结果的影响。与ICPC理论相比，在0.03～0.25m3/m3的含水率范围内，用PILS理论得到的砂土热扩散率和热导率分别偏低11.8%和5.2%；与模拟热容量相比，PILS和ICPC理论分别将热容量高估16.1%和7.9%；2）探针有限特性对土壤热特性的影响与含水率有关：在干土上最大；随着土壤含水率的增加，其影响逐渐降低。该研究对提高热脉冲技术测定土壤热特性的准确性具有指导意义。

关键词：土壤热传递含水率土壤热特性热脉冲技术探针有限特性

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17世纪英国文化领域性别纷争研究

文化创新比较研究 2024年第18期8卷 55-58页

作者：付晓燕伊犁师范大学旅游与历史文化学院新疆伊宁835000 伊犁师范大学伊犁学研究中心新疆伊宁835000

男女性别纷争一直是一个经久不衰的话题,15—17世纪,一直有零星的英国妇女从《圣经》中找寻男女平等的依据,并试图用宗教术语对女性劣根性的言论给予反驳,英国传统父权制社会中女性的隐形身份在近代早期被打破。17世纪的英国,厌女者及... 详细信息

男女性别纷争一直是一个经久不衰的话题,15—17世纪,一直有零星的英国妇女从《圣经》中找寻男女平等的依据,并试图用宗教术语对女性劣根性的言论给予反驳,英国传统父权制社会中女性的隐形身份在近代早期被打破。17世纪的英国,厌女者及反厌女者在文化领域展开的纷争备受关注。以往学者对近代早期英国的研究中,鲜少将目光投射在该时期文化领域展开的性别纷争上,与之相关的研究少之又少。故该文以近代早期英国文化领域展开的性别纷争为例,以期展现该时期英国社会的图景,并为相关研究提供参考。

关键词： 17世纪英国厌女主义性别纷争经济利益文化

软弱破碎围岩锚固孔树脂锚固剂流失对锚固性能影响研究

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中国矿业大学学报 2024年第3期53卷 483-496页

作者：付孟雄黄帅帅刘少伟贺德印张建英郭重托河南理工大学能源科学与工程学院河南焦作454000 煤炭安全生产与清洁高效利用省部共建协同创新中心河南焦作454000 伊犁永宁煤业化工有限公司新疆伊宁844500

树脂锚固剂作为锚杆与围岩的重要黏结剂,在锚固剂搅拌时软弱破碎围岩锚固孔壁裂隙可能会造成树脂锚固剂流失,影响锚固性能.因此,本文首先开展了基于3D打印高透光锚固孔裂隙模型的树脂锚固剂流失可视化试验,然后采用理论分析、数值模拟... 详细信息

树脂锚固剂作为锚杆与围岩的重要黏结剂,在锚固剂搅拌时软弱破碎围岩锚固孔壁裂隙可能会造成树脂锚固剂流失,影响锚固性能.因此,本文首先开展了基于3D打印高透光锚固孔裂隙模型的树脂锚固剂流失可视化试验,然后采用理论分析、数值模拟及实验室试验方法分析了树脂锚固剂流失对锚固性能的影响.结果表明:树脂与固化剂在锚杆运动作用下会快速向锚固孔壁裂隙流动,并在裂隙内部形成固化结构,使锚固长度缩短,系统的锚固性能随着裂隙数量、张开度、倾角及树脂锚固剂流入深度的增加而降低.围岩注浆改性、增加树脂锚固剂药卷数量以及锚固孔扩孔技术可削弱锚固剂流失带来的影响,提出了树脂锚固剂流失条件下锚固剂药卷用量计算表达式.本文可为软弱破碎围岩控制与锚固质量提升方法研究提供一定参考.

关键词：锚杆支护软弱破碎围岩孔壁裂隙树脂锚固剂流失锚固性能

School wear:Design,quality and standards go hand in hand

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China Textile 2014年第12期 30-31页

作者： Li yili

China School Wear ＂Safety and Stan- dards＂ Summit Forum, held on Oct. 25th in Ningbo International Conference ＆ Exhibition Center during the 18th Ningbo International Fashion Festival, made discussion on current safety standards of elementary and secondary school wear, including the safety standards of fabrics, accessories, technology, style design and structural design. The distinguished guests attending the Forum included： Sun Jianming, president of Party Commit- tee in Ningbo Municipal Commission of Education, Chen Jincai, vice chairman of The Sub-Council of Schools Logistics Equipment Management, China Educational Equipment Industry Association, Wang fu, president of China Educational Equipment Industry Association, Wu Ying, director of comprehensive labora- tory of Educational Equipment Research ＆ Development Center, Ministry of Edu- cation, and Ruan Lifang, the committee member of Technical Committee 219 on Garment of Standardization Administra- tion of China and senior engineer of Zhe- jiang Provincial Fiber Inspection Bureau.

关键词：学校标准中国教育设计磨损质量高峰论坛行业协会

Mechanical regulation of bone regeneration during distraction osteogenesis

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Medicine in Novel Technology and Devices 2021年第3期11卷 85-93页

作者： Ruisen fu yili Feng Youjun Liu Haisheng Yang Department of Biomedical Engineering Faculty of Environment and LifeBeijing University of TechnologyBeijingChina

Distraction osteogenesis(DO)is a mechanobiological process of regenerating bone tissue by tension *** is used clinically to lengthen bones or to treat critical size bone *** DO provides satisfactory results in many cases,the prolonged period of treatment remains a major challenge that needs to be *** attempts have been devoted to accelerating bone regeneration during *** common approach is manipulation of the applied mechanical loading by altering distraction *** this article,we reviewed relevant in vivo animal studies exploring the effects of changing mechanical environments,by varying distraction parameters(e.g.,rate and frequency)or adding compression loading,on bone regeneration in *** further presented how the mechanically-regulated bone regeneration process during DO could be simulated by in silico models incorporating mechano-regulatory tissue differentiation rules.A comprehensive review of those in vivo and in silico studies may not solely provide important references for development of improved DO protocols in clinic,but also promote a deeper understanding of the mechanobiological mechanism of bone regeneration.

关键词： Bone regeneration Computational modeling Distraction osteogenesis Mechanical loading Tissue differentiation

Analysis on Variations of the Temperature and Precipitation in North Slope Area of the Western Tianshan in Recent 50 Years

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Meteorological and Environmental Research 2011年第11期2卷 17-22页

作者： YAO fu-long,LI Hai-bing College of Chemistry and Biological Sciences,yili Normal University,Yining 835000,China

[Objective] The research aimed to analyze variation characteristics of the temperature and precipitation in north slope area of the Western Tianshan in recent 50 years.[Method] According to temperature and rainfall data from 1961 to 2010 at three meteorological stations in north slope area of the Western Tianshan,climate change in the zone in recent 50 years was analyzed by using linear trend analysis method and 5-year sliding average method.[Result] The temperature in north slope area of the Western Tianshan showed significant warming *** annual average temperature significantly increased at 0.3 ℃/10 a in recent 50 *** rise rates of the temperature in different seasons were different:autumn> winter> spring> *** annual rainfall in north slope area of the Western Tianshan in recent 50 years overall presented relative increase *** from annual rainfall,it significantly increased at 16.9 mm/10 *** from seasonal rainfall,except in autumn,rainfalls in other three seasons in the past 50 years all showed significant increase trends,with amplitude of 3.2-11.2 mm/10 *** largest increase amplitude was in *** a small precipitation peak in the 1980s,autumn rainfall slightly declined in the past 20 years.[Conclusion] The climate in north slope area of the Western Tianshan become warm and wet.

关键词： Climate change Temperature Precipitation North slope area of the Western Tianshan China

A Simple and Effective Boundary Model in Nonequilibrium Molecular Dynamics Method

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Chinese Journal of Polymer Science 2016年第9期34卷 1150-1157页

作者： Cui-liu fu 孙昭艳 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Xinjiang Laboratory of Phase Transitions and Microstructures in Condensed Matters College of Physical Science and Technology Yili Normal University Yining 835000 China

Abstract We propose a simple and effective boundary model in a nonequilibrium molecular dynamics （NEMD） simulation to study the out-of-equilibrium dynamics of polymer fluids. The present boundary model can effectively weaken the depletion effect and the slip effect near the boundary, and remove the unwanted heat instantly. The validity of the boundary model is checked by investigating the flow behavior of dilute polymer solution driven by an external force. Reasonable density distributions of both polymer and solvent particles, velocity profiles of the solvent and temperature profiles of the system are obtained. furthermore, the studied polymer chain shows a cross-streaming migration towards center of the tube, which is consistent with that predicted in previous literatures. These numerical results give powerful evidences for the validity of the present boundary model. Besides, the boundary model can also be used in other flows in addition to the Poiseuille flow.

关键词： Boundary condition Depletion effect Velocity profile Density distribution Nonequilibrium moleculardynamics.

Effect of Crystallization and Entropy Contribution Upon the Mechanical Response of Polymer Nano-fibers:A Steered Molecular Dynamics Study

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Chinese Journal of Polymer Science 2023年第3期41卷 465-474,I0011页

作者： Rui Ma Dan Xu Chuan-fu Luo Xinjiang Laboratory of Phase Transitions and Microstructures in Condensed Matters College of Physical Science and TechnologyYili Normal UniversityYining 835000China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China School of Applied Chemistry and EngineeringHefei 230026China

The mechanical response of polyethylene nano-fibers with the same chain length but different chain numbers are studied by using steered molecular dynamics *** shrinking or stretching forces acted on the chain ends are investigated according to the chain-end distance and temperature under isothermal or continuous warming-cooling conditions,*** inflection point is found in the ForceDistance response when temperature is below 500 *** inflection point is related to the balance between entropy force and inter-monomer interaction and it reflects the strong effect of crystallization on the mechanical response of the *** force at inflection point is also affected by the buckling effect due to increased stiffness when crystallization *** two stages found in the Force-Temperature response and the difference between the shrinking and stretching forces indicate the hysteresis of crystallization and *** forces at different shrinking and stretching rates reveal the entropy contribution upon the mechanical response,indicated by the Ramachandran plot of *** chain-conformation entropy is majorly contributed by dihedrals and is quantified by the information entropy of dihedrals,which has a highly similarity to the mechanical Force-Temperature *** enlarged forces in multiple chains over a single chain are attributed to the enhanced dihedral-conformation *** study provides a new insight to the dynamically mechanical response of polymer nano-fibers according to the effect of crystallization and entropy contribution.

关键词： Polymer fibers Crystallization Entropy contribution Mechanical response

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存储与计算的分离

计算机研究与发展 2005年第3期42卷 520-530页

作者：马一力傅湘林韩晓明许鲁中国科学院计算技术研究所国家高性能计算机工程技术中心北京100080

当前计算应用的发展对传统计算机体系结构提出了挑战.由计算资源和存储资源固定连接形成的系统已经不能适应动态计算的需求.从应用出发,提出计算资源和存储资源物理分离和逻辑分离的概念,并以此为基础,构造三维可重构计算环境可以解决... 详细信息

当前计算应用的发展对传统计算机体系结构提出了挑战.由计算资源和存储资源固定连接形成的系统已经不能适应动态计算的需求.从应用出发,提出计算资源和存储资源物理分离和逻辑分离的概念,并以此为基础,构造三维可重构计算环境可以解决这些问题.在这种环境中,用户程序、计算资源和存储资源可以根据应用的需求动态组合.由于摆脱了资源的地理位置和操作环境等方面的限制,计算过程将呈现出数据驱动的特点,从而实现按需计算,使计算系统可以在更大范围内为用户提供服务.

关键词：存储计算物理分离逻辑分离可重构计算环境