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基于ADAMS的某型冲锋枪自动机动力学仿真和分析

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计算机测量与控制 2024年第2期32卷 234-243页

作者：张红勇王智伟中北大学机电工程学院太原030051 内蒙动力机械研究所呼和浩特010011

为研究某型冲锋枪自动机运动规律和动力学特性,进而探究导气孔大小对自动机运动循环的影响,首先使用UG软件建立该枪自动机的三维实体模型,其次在ADAMS软件中建立虚拟样机,利用Matlab软件对内弹道和导气室压力曲线进行拟合,对该枪的单发... 详细信息

为研究某型冲锋枪自动机运动规律和动力学特性,进而探究导气孔大小对自动机运动循环的影响,首先使用UG软件建立该枪自动机的三维实体模型,其次在ADAMS软件中建立虚拟样机,利用Matlab软件对内弹道和导气室压力曲线进行拟合,对该枪的单发射击进行仿真,得到了枪机和枪机框的位移速度曲线、复进簧压力曲线等动力学特性,对比仿真结果与试验数据,说明虚拟样机模型具有较高的可行性,最后仿真分析导气孔大小对自动机运动循环的影响,仿真结果表明,随着导气孔直径增大,后坐速度和后坐撞击变大,复进到位速度明显提高,复进时间显著降低,自动循环时间相对缩减,为产品优化设计提供理论参考。

关键词：冲锋枪自动机动力学虚拟样机 ADAMS

MatDEM-fast matrix computing of the discrete element method

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Earthquake Research Advances 2021年第3期1卷 1-7页

作者： Chun Liu Hui Liu hongyong zhang School of Earth Sciences and Engineering Nanjing UniversityNanjing210023China

Discrete element method can effectively simulate the discontinuity,inhomogeneity and large deformation and failure of rock and *** on the innovative matrix computing of the discrete element method,the highperformance discrete element software MatDEM may handle millions of elements in one computer,and enables the discrete element simulation at the engineering *** supports heat calculation,multi-field and fluidsolid coupling numerical ***,the software integrates pre-processing,solver,postprocessing,and powerful secondary development,allowing recompiling new discrete element *** basic principles of the DEM,the implement and development of the MatDEM software,and its applications are introduced in this *** software and sample source code are available online(http://***).

关键词： Discrete element method High-performance MatDEM Matrix computing

Biosensors for waterborne virus detection: Challenges and strategies

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Journal of Pharmaceutical Analysis 2023年第11期13卷 1252-1268页

作者： Xixi Song Zina Fredj Yuqiao Zheng hongyong zhang Guoguang Rong Sumin Bian Mohamad Sawan CenBRAIN Neurotech School of EngineeringWestlake UniversityHangzhou310030China

Waterborne viruses that can be harmful to human health pose significant challenges globally,affecting health care systems and the *** these waterborne pathogens is essential for preventing diseases and protecting public ***,handling complex samples such as human and wastewater can be challenging due to their dynamic and complex composition and the ultralow concentration of target *** review presents a comprehensive overview of the latest breakthroughs in waterborne virus *** begins by highlighting several promising strategies that enhance the sensing performance of optical and electrochemical biosensors in human *** strategies include optimizing bioreceptor selection,transduction elements,signal amplification,and integrated sensing ***,the insights gained from biosensing waterborne viruses in human samples are applied to improve biosensing in wastewater,with a particular focus on sampling and sample pretreatment due to the dispersion characteristics of waterborne viruses in *** review suggests that implementing a comprehensive system that integrates the entire waterborne virus detection process with high-accuracy analysis could enhance virus *** findings provide valuable insights for improving the effectiveness of waterborne virus detection,which could have significant implications for public health and environmental management.

关键词： Waterborne viruses Biosensors Optical Electrochemical Human samples Wastewater

兴隆山自然保护区不同植被类型土壤碳含量特征研究

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甘肃林业科技 2024年第2期49卷 1-9页

作者：张红勇王寒冰欧涛王建辉甘肃兴隆山国家级自然保护区管护中心甘肃榆中730117 中国地质调查局烟台海岸带地质调查中心山东烟台264000 黄河流域(兰州段)水-土-生资源作用与效应野外科学观测研究站甘肃兰州730070

为研究甘肃兴隆山国家级自然保护区内不同植被类型(高寒草甸、灌丛、落叶松人工林)的土壤碳含量特征,采用对角线五点取样法收集0—60 cm土层样本,分析了土壤总碳(TC)、土壤有机碳(SOC)和土壤无机碳(SIC)含量。结果显示,SOC在各植被类型... 详细信息

为研究甘肃兴隆山国家级自然保护区内不同植被类型(高寒草甸、灌丛、落叶松人工林)的土壤碳含量特征,采用对角线五点取样法收集0—60 cm土层样本,分析了土壤总碳(TC)、土壤有机碳(SOC)和土壤无机碳(SIC)含量。结果显示,SOC在各植被类型土壤TC含量中占绝大比重,且在0—20 cm土层含量最高,随土层深度增加而减少;不同植被类型间,落叶松人工林的TC和SOC含量普遍高于高寒草甸和灌丛,表明落叶松人工林对土壤碳储存贡献显著;不同植被类型的SIC含量均很小,且在不同植被类型间表现出差异性,灌丛在0—40 cm土层中SIC含量较高,而落叶松人工林在整个土层中SIC含量相对稳定。本研究探析了自然保护区内不同植被类型对土壤碳储存功能的影响,为评估生态系统碳循环及制定保护措施提供科学依据。

关键词：兴隆山自然保护区土壤碳含量高寒草甸灌丛落叶松人工林

TPX2 knockdown suppressed hepatocellular carcinoma cell invasion via inactivating AKT signaling and inhibiting MMP2 and MMP9 expression

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Chinese Journal of Cancer Research 2014年第4期26卷 410-417页

作者： Qingquan Liu Pinghua Yang Kangsheng Tu hongyong zhang Xin Zheng Yingmin Yao Qingguang Liu Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi'an Jiaotong University Department of Hepatic Surgery Eastern Hepatobiliary Surgery Hospital

Objective： Targeting protein for Xenopus kinesin-like protein 2 （TPX2） is a nuclear proliferation-related protein that plays a critical role in the formation of mitotic spindle. High expression of TPX2 has been observed in several types of tumors. However, the role of TPX2 in hepatocellular carcinoma （HCC） remains unclear. Our study aimed to investigate the effect of TPX2 on HCC cell invasion. Methods： The immortalized normal human liver cell line L02 and six HCC cell lines including SMMC- 7721, BEL-7402, Huh-7, HepG2, Hep3B and SKHepl were subjected to qRT-PCR and western blot for TPX2 mRNA and protein, respectively. Furthermore, TPX2 small interfering RNA （siRNA） was used to knock down TPX2 expression in SMMC-7721 and HepG2 cells. Cell proliferation and invasion were determined by MTT and transwell assays. Otherwise, expression of p-AKT, MMP2 and MMP9 were evaluated by western blot in SMMC-7721 cells. Results： The expression of TPX2 in HCC cell lines was markedly higher than that in normal human liver cell line. TPX2 knockdown using a specific TPX2-siP, NA reduced the number of invaded cells and inhibited cell proliferation in SMMC-7721 and HepG2 cells. Furthermore, TPX2 knockdown resulted in inactivation of AKT signaling and down-regulation of MMP2 and MMP9 expression in SMMC-7721 cells. Conclusions： Our study identified that TPX2 might contribute to tumor cell invasion through activating AKT signaling and subsequently increasing MMP2 and MMP9 in HCC.

关键词： Targeting protein for Xenopus kinesin-like protein 2 (TPX2) hepatocellular carcinoma MMP2 MMP9

A harlequin ichthyosis pig model with a novel ABCA12 mutation can be rescued by acitretin treatment

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Journal of Molecular Cell Biology 2019年第12期11卷 1029-1041页

作者： Xiao Wang Chunwei Cao Yongshun Li Tang Hai Qitao Jia Ying zhang Qiantao Zheng Jing Yao Guosong Qin hongyong zhang Ruigao Song Yanfang Wang Guanghou Shui Sin Man Lam Zhonghua Liu Hong Wei Anming Meng Qi Zhou Jianguo Zhao State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Animal Nutrition Institute of Animal ScienceChinese Academy of Agricultural SciencesBeijing 100081China State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China College of Life Science Northeast Agricultural University of ChinaHarbin 150030China Department of Laboratory Animal Science College of Basic Medical SciencesThird Military Medical UniversityChongqing 400038China School of Life Sciences Tsinghua UniversityBeijing 100084China Chinese Swine Mutagenesis Consortium Beijing 100101China

Harlequin ichthyosis (HI) is a severe genetic skin disorder and caused by mutation in the ATP-binding cassette A12 (ABCA12) gene. The retinoid administration has dramatically improved long-term survival of HI, but improvements are still needed. However, the ABCA12 null mice failed to respond to retinoid treatment, which impedes the development of novel cure strategies for HI. Here we generated an ethylnitrosourea mutagenic HI pig model (named Z9), which carries a novel deep intronic mutation IVS49-727 A>G in the ABCA12 gene, resulting in abnormal mRNA splicing and truncated protein production. Z9 pigs exhibit significant clinical symptom as human patients with HI. Most importantly, systemic retinoid treatment significantly prolonged the life span of the mutant pigs via improving epidermal maturation, decreasing epidermal apoptosis, and triggering the expression of ABCA6. Taken together, this pig model perfectly resembles the clinical symptom and molecular pathology of patients with HI and will be useful for understanding mechanistic insight and developing therapeutic strategies.

关键词： harlequin ichthyosis ABCA12 pig model acitretin ENU mutagenesis deep intronic mutation

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基坑开挖对临近地铁隧道力学性状的影响研究

公路工程 2014年第5期39卷 286-289,294页

作者：张红勇中国中铁二院工程集团有限责任公司云南昆明650200

基坑开挖对临近既有隧道影响的计算与评价是基坑工程实施过程中必须考虑的关键问题之一,以某基坑开挖为算例,按照隧道-土体-基坑围护结构共同作用,建立了三维非线性有限元模型。计算了基坑边线与隧道轴线成0°、30°、60°和90°夹角的... 详细信息

基坑开挖对临近既有隧道影响的计算与评价是基坑工程实施过程中必须考虑的关键问题之一,以某基坑开挖为算例,按照隧道-土体-基坑围护结构共同作用,建立了三维非线性有限元模型。计算了基坑边线与隧道轴线成0°、30°、60°和90°夹角的4种工况,分析基坑与隧道轴线不同交角条件下,基坑开挖对隧道结构变形和内力的影响。结果表明:随着基坑开挖深度的增加,基坑开挖引起隧道结构变形和内力的改变更加明显;随着与基坑距离的增大,隧道结构受基坑开挖的影响逐渐减弱;隧道与基坑的相对位置不同,基坑开挖引起隧道结构的受力变形差异明显,随着二者交角的增大,隧道结构的竖向变形逐渐增大,侧向变形逐渐减小,而轴力和弯矩变化较为复杂。

关键词：基坑地铁隧道数值分析变形内力

白垩纪含介形类化石岩石样品处理方法的对比研究

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微体古生物学报 2021年第2期38卷 180-186页

作者：贾宝岩张红勇中国科学院南京地质古生物研究所生物演化与环境卓越创新中心现代古生物学与地层学国家重点实验室南京210008 中国科学院大学北京100049 中国科学院南京地质古生物研究所实验技术中心南京210008

为了确定从坚硬且致密的含介形类化石样品中高效获得介形类化石的处理方法,本研究对三种白垩纪含介形类化石样品:产自吉林白山盆地的含凝灰钙质粉砂质泥岩、凝灰质灰岩和英国典型Purbeck-Wealden沉积区的石灰岩,采取多种方法进行处理。... 详细信息

为了确定从坚硬且致密的含介形类化石样品中高效获得介形类化石的处理方法,本研究对三种白垩纪含介形类化石样品:产自吉林白山盆地的含凝灰钙质粉砂质泥岩、凝灰质灰岩和英国典型Purbeck-Wealden沉积区的石灰岩,采取多种方法进行处理。处理方法包括过氧化氢法、表面活性剂法、液氮法、冰醋酸法(常温和沙浴70℃)和氢氟酸法。实验结果表明:针对含凝灰钙质粉砂质泥岩最有效的处理方法是表面活性剂法;凝灰质灰岩只能使用氢氟酸法进行处理;针对石灰岩样品最优的处理方法为冰醋酸法(沙浴70℃)。

关键词：介形类样品处理东北地区英国Purbeck-Wealden

Integrating linear and nonlinear models to assess the built environment’s impact on older adults’behaviors in China

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Chinese Journal of Population,Resources and Environment 2024年第2期22卷 146-156页

作者： Xiaoping Wang Zeyan Li Fang Wu Meng zhang hongyong Liu School of Civil Engineering and Geomatics Southwest Petroleum UniversityChengdu 610500China Jinan University-University of Birmingham Joint Institute Jinan UniversityGuangzhou 511443China School of Civil Engineering Hebei University of EngineeringHandan 056038China

China is experiencing rapid population *** one contributing factor affecting senior citizens’lives is the disconnect between the built environment in urban and rural areas and the behavioral preferences of older ***,research on the relation between the built environment and the behavior of older individuals has been ***,this paper uses the most recent health tracking data on factors influencing aging in China released in 2020(China Senior Health Survey Tracking Survey).Applying traditional regression,least absolute shrinkage and selection operator regression,and two decision tree optimization models from machine learning,a comprehensive comparative study is carried out to investigate the correlation between the built environment and the physical activity,dietary habits,and social interactions of older age *** findings reveal that built environment variables most significantly impact physical activity,accounting for 52.525%,followed by social interaction behaviors at 50.202%and dietary intake at 47.991%.Furthermore,the authors identify population density and greenness rate as the built environment factors having considerable effects on the behavior of older ***,this study establishes a theoretical foundation for developing age-friendly community environments for older adults.

关键词： Built environment Behavioral activity Aging Machine learning