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低含水率粉质壤土中搅拌桩施工方案试验研究

人民珠江 2024年第9期45卷 93-100页

作者：赵满江李鹏杜志军韩泽张悦朱常志河北省水利工程局集团有限公司第一分公司河北保定071000 河北省水建水电工程有限公司河北保定071000 河北农业大学城乡建设学院河北保定071000

为解决中国北方地区低含水率粉质壤土中水泥土搅拌桩施工过程中钻头钻进搅拌困难的实际问题,以河北省白沟河治理工程(涿州段)东茨排水涵闸闸基水泥土搅拌桩地基处理工程为背景,开展预浸水法和较高水灰比法两种施工方案的可行性现场试验... 详细信息

为解决中国北方地区低含水率粉质壤土中水泥土搅拌桩施工过程中钻头钻进搅拌困难的实际问题,以河北省白沟河治理工程(涿州段)东茨排水涵闸闸基水泥土搅拌桩地基处理工程为背景,开展预浸水法和较高水灰比法两种施工方案的可行性现场试验研究,通过对现场施工速度和水泥土抗压强度等参数的实测,对比分析了2种方案在该场地条件下的可行性。结果表明,预浸水法和较高水灰比法在低含水率粉质壤土中均具有工程适用性,但较高水灰比法在施工效率和施工效果等方面均优于预浸水法,且在粉质壤土条件下,采用较高水灰比法施工时,同时满足施工质量和经济性的最优水灰比为1.5。该研究成果为低含水率粉质壤土中水泥土搅拌桩施工方案选择提供了新的思路,也为类似条件下的水泥土搅拌桩施工提供了可靠的施工技术参数。

关键词：低含水率粉质壤土水泥土搅拌桩施工方案优化最优水灰比

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Mathematic model of rolling pressure during a semisolid shearing-rolling process

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International Journal of Minerals,Metallurgy and Materials 2012年第12期19卷 1121-1127页

作者： Ren-guo Guan Zhan-yong zhao Chao Lian Qiu-sheng Zhang chun-ming Liu College of Materials and Metallurgy Northeastern UniversityShenyang 110819China

A mathematic model of rolling pressure during a novel semisolid shearing-rolling process was established. The rolling pressure in this process is higher than that in the conventional rolling. The increment of rolling pressure in the backward slip zone is higher than that in the forward slip zone, and the neutral plane moves toward to the roll gap entrance. The maximum and the average rolling pressures increase with the decrease of strip thickness, and the effects of strip thickness on the rolling pressure is more obvious in the forward slip zone than in the backward slip zone. Meanwhile, the neutral plane moves toward the roll gap exit with the decrease of strip thickness. The maximum and average rolling pressures increase with the decrease of strip width, and the strip width affects the pressure more obviously in the backward slip zone than in the forward slip zone. At the same time, the neutral plane moves toward the roll gap entrance with the decrease of strip width. The maximum and average rolling pressures increase with increasing roll radius, and the neutral plane moves toward the roll gap exit.

关键词： semisolid rolling pressure mathematic models strips magnesium alloys

ZBP1(DAI/DLM-1) promotes osteogenic differentiation while inhibiting adipogenic differentiation in mesenchymal stem cells through a positive feedback loop of Wnt/β-catenin signaling

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Bone Research 2020年第2期8卷 219-228页

作者： Xuefeng zhao Liang Xie Zhiyong Wang Jiongke Wang Hao Xu Xianglong Han Ding Bai peng Deng State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesChinese Academy of Medical Sciences Research Unit of Oral Carcinogenesis and ManagementWest China Hospital of StomatologySichuan UniversityChengduSichuan 610041PR China Department of Orthodontics West China Hospital of StomatologySichuan UniversityChengduSichuan 610041PR China

The lineage specification of mesenchymal stem/stromal cells(MSCs) is tightly regulated by a wide range of factors. Recently, the versatile functions of ZBP1(also known as DAI or DLM-1) have been reported in the blood circulation and immune ***, the biological function of ZBP1 during the lineage specification of MSCs is still unknown. In the present study, we found that ZBP1 was upregulated during osteogenesis but downregulated during adipogenesis in mouse bone marrow-derived MSCs(m BMSCs). ZBP1 was highly expressed in osteoblasts but expressed at a relatively low level in marrow adipocytes. Knockdown of ZBP1 inhibited alkaline phosphataseactivity, extracellular matrix mineralization, and osteogenesis-related gene expression in vitro and reduced ectopic bone formation in vivo. Knockdown of ZBP1 also promoted adipogenesis in MSCs in vitro. Conversely, the overexpression of ZBP1 increased the osteogenesis but suppressed the adipogenesis of MSCs. When the expression of ZBP1 was rescued, the osteogenic capacity of ZBP1-depleted m BMSCs was restored at both the molecular and phenotypic ***, we demonstrated that ZBP1, a newly identified target of Wnt/β-catenin signaling, was required for β-catenin translocation into nuclei. Collectively, our results indicate that ZBP1 is a novel regulator of bone and fat transdifferentiation via Wnt/β-catenin signaling.

关键词： inhibited inhibiting versatile

基于战场电磁效应目标的复杂电磁环境构设研究

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雷达与对抗 2024年第2期44卷 1-6页

作者：彭进先高澜桑苗苗秦剑琪耿丹赵超 63611部队新疆库尔勒841001 63618部队新疆库尔勒841001

针对部队训练构设的复杂电磁环境与实战电磁环境对受训力量作用效果不一致的问题,提出基于战场电磁效应目标一致的复杂电磁环境构设方法。先将电磁效应目标分解到时域、频域、空域、能域、调制域、极化域等“六域”中,通过多域差异补偿... 详细信息

针对部队训练构设的复杂电磁环境与实战电磁环境对受训力量作用效果不一致的问题,提出基于战场电磁效应目标一致的复杂电磁环境构设方法。先将电磁效应目标分解到时域、频域、空域、能域、调制域、极化域等“六域”中,通过多域差异补偿分析和“缩比映射”构设运用,实现构设环境与实战环境对受训力量的电磁效应目标一致,最后给出构设逼真度计算方法,并通过案例分析进行仿真验证。

关键词：复杂电磁环境构设方法战场电磁效应多域差异补偿逼真度

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基于粗糙分析的大学英语考试质量提升路径

当代教育理论与实践 2024年第1期16卷 57-63页

作者：柳媛慧陈林书赵肄江彭理梁伟湖南科技大学外国语学院湖南湘潭411201 湖南科技大学计算机科学与工程学院湖南湘潭411201

大学英语考试是检验大学英语教学质量和效果的有效手段。将粗糙集理论应用于大学英语考试命题,基于粗糙集的相对正域、冗余属性和属性重要度等概念,给出试题冗余性的定性判别方法,提出试题重要度的定量度量方法,建立基于粗糙分析的大学... 详细信息

大学英语考试是检验大学英语教学质量和效果的有效手段。将粗糙集理论应用于大学英语考试命题,基于粗糙集的相对正域、冗余属性和属性重要度等概念,给出试题冗余性的定性判别方法,提出试题重要度的定量度量方法,建立基于粗糙分析的大学英语考试质量提升模型。实验结果表明,新型方法发现并修正了部分冗余和重要度较低的试题,有效提高了试卷命题质量,对指导大学英语教学工作、提升教学质量具有重要指导意义。

关键词：大学英语考试粗糙集试题冗余性试题重要性质量提升

Oxidation mechanism of high-volume fraction SiCp/Al composite under laser irradiation and subsequent machining

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纳米技术与精密工程(英文) 2023年第3期6卷 34-47页

作者： Hanliang Liu Guolong zhao Zhiwen Nian Zhipeng Huang Kai Yang Conghua Liu peng Wang Zhenkuan Diao Beijing Spacecrafts Beijing 100094People’s Republic of China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Conventional mechanical machining of a composite material comprising an aluminum matrix reinforced with a high volume fraction of SiC particles(hereinafter referred to as an SiCp/Al composite)faces problems such as rapid tool wear,high specific cutting force,and poor surface ***,a promising method for solving these problems is laser-induced oxidation-assisted milling(LOAM):under laser irradiation,the local workpiece material reacts with oxygen,thus forming loose and porous oxides that are easily *** the present work,the oxidation mechanism of SiCp/Al irradiated by a nanosecond pulsed laser is studied to better understand the laser-induced oxidation behavior and control the characteristics of the oxides,with laser irradiation experiments performed on a 65%SiCp/Al composite with various laser parameters and auxiliary gases(oxygen,nitrogen,and argon).With increasing laser pulse energy density,both the ablated groove depth and the width of the heat-affected zone *** oxygen is used as the auxiliary gas,an oxide layer composed of SiO_(2)and Al2O3 forms,and CO_(2)is produced and escapes from the material,thereby forming pores in the ***,when nitrogen or argon is used as the auxiliary gas,a recast layer is produced that is relatively difficult to *** laser irradiation,the sputtered material reacts with oxygen to form oxides on both sides of the ablated groove,and as the laser scanning path advances,the produced oxides accumulate to form an oxide *** and conventional milling are compared using the same milling parameters,and LOAM is found to be better for reduced milling force and tool wear and improved machined surface quality.

关键词： SiCp/Al composite Oxidation mechanism Nanosecond pulsed laser Laser-induced oxidation Heat-affected zone

Effects of outer rim of rotors on performance of turbodrills

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排灌机械工程学报 2019年第3期37卷 199-203页

作者： GONG Pan GUO Chaohui FENG Ding WANG peng zhao Yu XIANG Ru College of Mechanical Engineering Yangtze University Hubei Engineering Research Center for Oil & Gas Drilling and Completion Tools SINOPEC Research Institute of Petroeum Engineering Hubei Cooperative Innovation Center of Unconventional Oil and Gas

Two turbine rotors with outer rim and without outer rim were designed to analyze the influence of outer rim of rotors on the performance of a turbodrill. Two 3D models of the turbine rotor with different structures were established by SolidWorks software. The numerical simulation analysis of the turbine with different rotor structures was carried out based on software of fluent and then the performance of them at different rotating speeds was obtained. The results show that the torque,pressure drop and hydraulic efficiency of the turbine rotor with outer rim are greater than that of the turbine rotor without outer rim. By comparing the turbine rotor with outer rim and without outer rim,its torque increases 20. 1%,pressure drop increases 8.7% and hydraulic efficiency increases 10.4% at the maximum efficiency point. The related research is of guiding significance to further optimization of turbine rotor structure.

关键词： turbine rotor outer rim performance numerical simulation

Magnetic alloy cores for the HIRFL-CSRm compressor cavity

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Nuclear Science and Techniques 2011年第2期22卷 118-121页

作者： MEI Lirong XU Zhe YUAN Youjin JIN peng BIAN Zhibin zhao Hongwei Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Four types of magnetic alloy cores,labeled as V1,V2,A1 and A2,were produced by Liyuan ***.,for the radio frequency compression cavity of *** this work,their permeability,quality factor (Q value) and shunt impedance were measured before installing them into the *** results show that the V1,V2 and A2 have higher permeability and shunt impedance,and lower Q value,and are suitable to the radio frequency compression cavity.

关键词： HIRFL CSRM 压缩机磁合金磁芯无线电频率阻抗测量品质因数

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纳米零价铁对化工污染土壤修复研究现状

辽宁化工 2024年第1期53卷 103-105页

作者：赵文媛王春勇李英田沙沙辽宁工业大学化学与环境工程学院辽宁锦州121001

纳米零价铁(nZVI)作为一种新型的环境修复材料,被广泛应用于环境污染物的去除。介绍了nZVI的结构和特性,并重点综述了nZVI修复化工污染土壤中涉及的重金属和有机物污染的研究现状。最后展望了应用nZVI进行土壤修复的发展趋势。

关键词：纳米零价铁土壤修复重金属有机物

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