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Journal of Mountain Science 2024年第4期21卷 1432-1443页

作者： SHI Yunfang LI Shengang JIANG Chen liu jinning School of Resources and Civil engineering Northeastern UniversityShenyang 110004China

The compaction characteristics of gravelly soil are affected by gravel *** investigate the evolution and influencing mechanism of different gravel hardness on the compaction characteristics of gravelly soil,heavy compaction tests and crushing tests were conducted on gravelly soils with gravels originated from hard,soft and extremely soft *** to orthogonal experiments and variance analysis,it was found that hardness has a significant impact on the maximum dry density of gravelly soil,followed by gravel content,and lastly,moisture *** gravel compositions with an average saturated uniaxial compressive strength less than 60 MPa,the order of compacted maximum dry density is soft gravels>hard gravels>extremely soft *** type of gravelly soil has a threshold for gravel content,with 60%for hard and soft gravels and 50%for extremely soft *** these thresholds,the compacted dry density decreases *** is a certain interaction between hardness,gravel content,and moisture *** hardness increases the influence of gravel content,whereas lower hardness increases the influence of moisture *** soils with the coarse aggregate(CA)between 0.7 and 0.8 typically achieve higher dry densities after *** addition,the prediction equations for the particle breakage rate and CA ratio in the Bailey method were proposed to estimate the compaction performance of gravelly soil *** results further revealed the compaction mechanism of different gravelly soils and can provide reference for subgrade filling construction.

关键词： Gravelly soil Hardness Compaction characteristics Crushing characteristics Particle breakage rate Bailey method

Safety analysis of temporary anchorage system for immersed tube in Shenzhen-Zhongshan Link

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Journal of Traffic and Transportation engineering(English Edition) 2024年第4期11卷 797-813页

作者： Lei Yan jinning Yan Guoping Xu Shuanhai He Zechen Zhang School of Highway Chang'an UniversityXi'an 710064China Key Laboratory of Transport Industry of Bridge Detection Reinforcement Technology Chang'an UniversityXi'an 710064China CCCC Highway Consultants Co.Ltd. Beijing 100088China

In the construction of the Shenzhen-Zhongshan Link,a temporary anchorage system,distributed uniformly along the pipe wall,has been *** assess the safety and reliability of this system,a combined method utilizing numerical analysis and model experiments was applied to study the safety of the temporary anchorage system and the reliability of the tension ***,an overall model of the caisson segment based on GINA rebound force was established to analyze the stress state of the entire ***,a comprehensive numerical analysis and model experiment verification were conducted for the single tensioning system,revealing its failure mode and safety *** results indicate that the tension rod systems are uniformly stressed at an average of 444 k N during underwater jointing,with a safety factor of *** this point,the maximum von Mises stresses appearing at the front plate corners and the lower edge of the U-groove,with stress values of 181.8 MPa and 172.4 MPa,and safety factors of 1.54 and 1.71,*** the tension rod force reaches 940 k N,the tensioning system reaches its bearing limit,with initial yielding occurring at the front plate *** experiments were conducted to verify the theoretical analysis results,under a test load of 444 k N,the stresses at the front plate corners and the lower edge of the U-groove were 159.6 and 195.9 MPa,*** the test load increased to 940 k N,these stresses reached 390 and 389 MPa,exhibiting good agreement with the numerical *** the uncertainty of loads and materials,a reliability analysis of the tension rods was conducted,yielding a reliability index of 4.34,meeting the secondary safety *** on the comprehensive analysis,it can be concluded that the temporary anchorage system in the caisson segments of the Shenzhen-Zhongshan Link exhibits excellent safety margins.

关键词： Tunnel engineering Immersed tube structure Anchorage system Full-scale model test Load bearing performance Safety assessment

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碎石土路基填料压实及渗透特性

工程科学学报 2024年第5期46卷 918-926页

作者：李慎刚石云方刘晋宁蒋琛东北大学资源与土木工程学院沈阳110891

为揭示碎石土路基填料在压实及渗透过程中的颗粒破碎、流失规律,对不同含石量及含水率的碎石土试样进行击实及击实后的渗透试验.结果表明:对于碎石为硬岩、细颗粒为砂类土的碎石土试样,在碎石质量分数(简称含石量)为60%时达到最大干密度... 详细信息

为揭示碎石土路基填料在压实及渗透过程中的颗粒破碎、流失规律,对不同含石量及含水率的碎石土试样进行击实及击实后的渗透试验.结果表明:对于碎石为硬岩、细颗粒为砂类土的碎石土试样,在碎石质量分数(简称含石量)为60%时达到最大干密度;击实破碎前后的粒径分布具有良好的分形特征,分形维数D与干密度呈现正相关,破碎最优分形维数区间粗颗粒为2.23~2.25、细颗粒为2.43~2.45;建立了分形维数D与含石量和含水率的关系式可以对分形维数D进行预测并进一步估计压实效果;破碎率B_(g)与分形维数D也有良好的线性关系,含石量不超过60%时,粗、细颗粒的分形维数D均随颗粒破碎率B_(g)的增加而增加;渗透侵蚀对分形维数D的影响受含石量的影响较大,60%含石量时,分形维数差值随含水率的增大先减小后增大,与渗透系数的变化趋势相同.含石量和含水率是影响颗粒破碎、流失的两个重要因素,但相对于含水率而言,含石量对颗粒破碎、流失的影响更加显著,分形维数D与各配比试样的击实、渗透试验结果的相关性良好,能够较好地反映碎石土试样的压实及渗透特性,可进一步揭示碎石土路基的压实机理,也可为路基工程施工提供参考.

关键词：碎石土击实试验颗粒破碎分形维数渗透侵蚀

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球黏土对单及多组分重金属离子的吸附效果

农业工程学报 2024年第4期40卷 245-253页

作者：陈榕王彪郝冬雪高晋宁王伟卓高宇聪东北电力大学岩土工程研究所吉林132012 东北电力大学吉林省电力基础设施安全评估与灾害防治重点实验室吉林132012

重金属污染水的防范和治理一直是国际上的难点和热点研究课题。吸附法具有经济可行和环境友好等优点,被认为是去除水中重金属离子的最佳技术。球黏土具有潜在的高吸附性能,为进一步探索利用球黏土治理重金属污染水的可行性,该研究通过... 详细信息

重金属污染水的防范和治理一直是国际上的难点和热点研究课题。吸附法具有经济可行和环境友好等优点,被认为是去除水中重金属离子的最佳技术。球黏土具有潜在的高吸附性能,为进一步探索利用球黏土治理重金属污染水的可行性,该研究通过单组分与多组分重金属离子的批式吸附试验,重点考察球黏土对Pb^(2+)、Cu^(2+)、Zn^(2+)、Cd^(2+)、Cr^(6+)的吸附效果和竞争吸附关系。单组分离子吸附试验表明,球黏土对重金属离子的吸附量遵循先快速增加后缓慢增长,随pH值的增大而增大,随初始浓度增加而增加,直至吸附饱和的规律。最佳吸附平衡时间为90 min;最佳溶液pH值为5。pH值对球黏土吸附5种重金属离子的影响程度由大到小依次为Zn^(2+)、Cd^(2+)、Cr6+、Cu^(2+)、Pb^(2+),当pH值从2增到5时,Zn^(2+)吸附量提高了184%。球黏土对5种离子Pb^(2+)、Cr^(6+)、Zn^(2+)、Cd^(2+)、Cu^(2+)的饱和吸附量分别为311.847、301.437、263.213、195.435和179.635 mg/g。通过动力学模型和等温线模型拟合,吸附数据更加符合准二阶动力学模型和Langmuir等温吸附模型,说明吸附过程为单层吸附,吸附方式为化学吸附,最大吸附量依次为Pb^(2+)(497.593 mg/g)>Cr6+(442.868 mg/g)>Zn^(2+)(339.376 mg/g)>Cd^(2+)(290.039 mg/g)>Cu^(2+)(194.941 mg/g)。多组分离子吸附试验表明,球黏土对4种离子的吸附量同样呈先快速后缓慢增长,直至平稳的趋势。各离子在球黏土的活性位点上表现出的竞争能力由强到弱依次为Cr^(6+)、Zn^(2+)、Cd^(2+)、Cu^(2+)。通过等温线模型拟合,发现多组分重金属离子吸附数据更加符合Langmuir等温吸附模型,吸附方式和吸附过程与单组分一致,各组分的最大吸附量与单组分相比有所下降,但吸附总量却大大增加,说明球黏土对多组分重金属离子具有良好的吸附能力。与其他原生矿物材料相比,球黏土对重金属离子具有更大的吸附量,该研究成果可为球黏土作为吸附剂的利用和推广提供理论依据和数据支持,具有较大的现实意义。

关键词：重金属等温线动力学球黏土单组分吸附多组分吸附

Development　of　an　engineering－practical　expert　system　for　arc　welding　and　its　shell

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China Welding 1994年第1期3卷 60-68页

作者： Peng jinning Chen Bingsen and liu Qiang(Qinghua University, Beijing)

The major functions of an engineering-practical expert system(ESW) and the main features of an expert system development tool(QHWEST) for arc welding procedure are introduced. A brief description is given for the deve... 详细信息

关键词： arc welding procedure expert system development tool development technique

基于RBF滑模控制的分布式驱动电动车辆转向稳定性研究

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汽车实用技术 2024年第20期49卷 1-8,18页

作者：闫文志智晋宁靳峰太原科技大学机械工程学院山西太原030024

分布式驱动电动车辆四轮转矩独立可控,驱动电机响应较快、传动链短,但在转弯时由于车轮纵向力和侧向力之间的耦合关系,使车辆容易发生侧滑风险。因此,为提高分布式驱动电动车辆的转向稳定性,文章提出基于径向基函数(RBF)神经网络改进的... 详细信息

分布式驱动电动车辆四轮转矩独立可控,驱动电机响应较快、传动链短,但在转弯时由于车轮纵向力和侧向力之间的耦合关系,使车辆容易发生侧滑风险。因此,为提高分布式驱动电动车辆的转向稳定性,文章提出基于径向基函数(RBF)神经网络改进的滑模控制策略。整车采用分层控制结构,上层采用滑模控制器对横摆力矩进行控制,为避免“抖振”问题,引入RBF神经网络对传统滑模控制算法中的滑模增益进行优化改进;下层驱动力分配层根据轮胎垂向载荷的动态转移特性对四轮转矩进行合理分配,使其满足整车驱动力和附加横摆力矩需求,最后在CarSim和MATLAB/Simulink中进行联合仿真。结果表明,改进的滑模控制器在高速工况可以减小汽车前轮转角,转弯时横摆角速度、质心侧偏角分别可降低0.1 rad/s和0.01 rad,低速工况下横摆角速度和质心侧偏角分别可降低0.12 rad/s和0.013 rad,有效地改善车辆稳定性。

关键词：分布式驱动电动车辆滑模控制稳定性转矩分配 CarSim MATLAB/Simulink

Synthesis and Characterization of a Hydroxyethyl Derivative of Chitosan and Evaluation of Its Biosafety

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Journal of Ocean University of China 2015年第4期14卷 703-709页

作者： SHAO Kai HAN Baoqin GAO jinning SONG Fulai YANG Yan liu Wanshun college of Marine Life Science Ocean University of China

Hydroxyethyl chitosan （HE-chitosan） is a water-soluble derivative of chitosan with many apparent biological properties. For example, it is non-toxic and rapidly biodegradable. Moreover, HE-chitosan has advantages in water-solubility, moisture retention and gelling property due to its hydroxyethyl group. However, the biocompatibility and biodegradability of this multifimctional de- rivative have rarely been documented although they are critical for its application in biomedical and clinical treatments. The purpose of this work was to evaluate the biosafety of HE-chitosan, and draw important clues for its diverse applications. HE-chitosan was synthesized and characterized its chemical structure with FTIR. Its molecular weight （Mw） was determined by gel permeation chro- matography （GPC）, and its deacetylation degree （DD） was investigated through potentiometric analysis. The cytotoxicity of HE-chitosan on mouse fibroblast cell L929 was tested. The biocompatibility and biodegradability of HE-chitosan in rat and rabbit were evaluated. The FTIR results indicated that the hydroxyethyl groups were linked to C6 of chitosan. The GPC analysis confirmed that its Mw was about 90.01 kDa. It was also demonstrated that HE-chitosan had excellent biocompatibility and biodegradability in vivo and had no cytotoxicity on L929. These findings indicated that HE-chitosan can potentially be applied as a biomaterial in tissue engineering, drug delivery, and other biomedical fields.

关键词： hydroxyethyl chitosan biomaterial cytotoxicity biocompatibility biodegradability

胰高血糖素样肽1受体激动剂治疗阿尔茨海默病的潜在靶点预测及验证

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中国组织工程研究 2024年第16期28卷 2568-2573页

作者：韩维娜徐晓庆史晋宁李欣儒蔡红艳邵阳学院普爱医学院(医学部)生理学教研室湖南省邵阳市422000 山西医科大学生理学系山西省太原市030000 山西医科大学基础医学院微生物与免疫教研室山西省太原市030000

背景:阿尔茨海默病的机制探究过程中揭示了生物信息学对共同靶点筛选的重要作用,能够利用其筛选结果为基础,探究药物对该疾病的治疗效果。目的:采用生物信息学与分子生物学等方法预测胰高血糖素样肽1受体激动剂利拉鲁肽治疗阿尔茨海默... 详细信息

背景:阿尔茨海默病的机制探究过程中揭示了生物信息学对共同靶点筛选的重要作用,能够利用其筛选结果为基础,探究药物对该疾病的治疗效果。目的:采用生物信息学与分子生物学等方法预测胰高血糖素样肽1受体激动剂利拉鲁肽治疗阿尔茨海默病的作用靶点。方法:利用DisGeNET数据库及SEA数据库获取阿尔茨海默病和利拉鲁肽作用的共同基因;利用DAVID在线数据库对共同靶点进行GO/KEGG富集分析;使用STRING数据库构建蛋白互作网络;使用CCK-8判断利拉鲁肽的最佳使用剂量;使用免疫荧光和免疫印迹技术对关键蛋白的表达情况进行分析。采用小鼠海马神经元HT22细胞系进行体外实验,细胞被随机分为3组:HT22组、HT22+Aβ组和HT22+Aβ+Lir组。HT22组不做特殊处理,HT22+Aβ组使用Aβ1-42干预HT22细胞系24 h构建Aβ损伤细胞模型,HT22+Aβ+Lir组在HT22+Aβ组的基础上添加利拉鲁肽12 h。结果与结论:①从DisGeNET数据库筛选出阿尔茨海默病相关联的基因,共得到3333个关联基因。再从SEA数据库中,得到利拉鲁肽的潜在作用靶点147个。最后使用R包筛选出阿尔茨海默病与利拉鲁肽共同靶点64个。②用DAVID数据库进行共同靶点的GO/KEGG分析,结果提示共同靶点主要富集在:神经活性配体-受体相互作用、肾素-血管紧张素系统、膀胱癌、内肽酶活性、肽受体活性、G蛋白偶联肽受体活性和转运囊泡等生物进程。③将已经得到的64个共同靶点蛋白导入至SRTING在线数据库进行蛋白互作网络构建,得到排名前3位的基因为基质金属蛋白酶2,9和白细胞介素1β。④采用CCK-8试剂盒检测了培养细胞的活性,确定利拉鲁肽拮抗Aβ1-42的最佳浓度为100 nmol/L。⑤在免疫印迹实验与免疫荧光实验中,较HT22组相比,在HT22+Aβ组内基质金属蛋白酶2,9和白细胞介素1β表达量明显上升(P<0.05);HT22+Aβ+Lir组较HT22+Aβ组相比基质金属蛋白酶2,9和白细胞介素1β的表达量显著下降(P<0.05)。⑥结合上述生物信息学数据及在GEO数据库的差异基因二次验证结果提示,基质金属蛋白酶2,9和白细胞介素1β均可作为利拉鲁肽治疗阿尔茨海默病的潜在作用靶点。

关键词：阿尔茨海默病利拉鲁肽胰高血糖素样肽1受体生物信息学 DisGeNET数据库 SEA数据库 GEO数据库 MMP9 MMP2 白细胞介素1β

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独立型微电网VSG控制参数分析及定量计算

电工技术 2024年第6期 121-124页

作者：谢能旺刘金宁郭鑫钟明威王力浩陆军工程大学河北石家庄050051

针对VSG控制原理无法为独立型微电网提供必要的惯量支撑以及阻尼作用的问题,通过建立VSG控制的小信号,分析VSG控制中2个重要参数J和D对系统稳定性的影响以及作用机理,确定了2个参数的选取原则,最后通过MATLAB/Simulink仿真验证其正确性。

关键词：独立型微电网虚拟同步发电机虚拟惯量阻尼系数