检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

玄武岩纤维复合材料梁-柱式护栏防撞性能

振动与冲击 2019年第21期38卷 265-270页

作者：孙胜江朱长华梅葵花长安大学公路学院西安710064 山东省交通规划设计院济南250031

针对目前桥梁护栏在使用过程中出现的碰撞性能差、使用寿命短等问题,提出连续玄武岩纤维复合材料(BFRP)护栏。首先建立护栏碰撞仿真体系,然后利用非线性显式动力学软件LS-DYNA模拟BFRP护栏碰撞过程,并与钢制梁柱式护栏作对比。结果表明... 详细信息

针对目前桥梁护栏在使用过程中出现的碰撞性能差、使用寿命短等问题,提出连续玄武岩纤维复合材料(BFRP)护栏。首先建立护栏碰撞仿真体系,然后利用非线性显式动力学软件LS-DYNA模拟BFRP护栏碰撞过程,并与钢制梁柱式护栏作对比。结果表明,碰撞过程中系统沙漏能小于10%的总能量,有限元模拟过程具有良好的仿真性能;在碰撞过程中车辆没有出现翻越、骑跨及穿越护栏的现象,BFRP护栏具有良好的导向性能;在碰撞过程中座椅位置处的纵横向加速度值均小于规范容许值,BFRP护栏对车辆有着良好的缓冲功能;相比钢护栏,BFRP护栏在碰撞过程中能够更好地降低车辆的加速度值,能够更好地吸收碰撞能量,因此BFRP护栏防撞性能要优于钢护栏。

关键词：桥梁玄武岩纤维复合材料数值模拟护栏碰撞加速度能量吸收

Current research status and research hotspots in Chinese geriatric medicine: Data retrieved from the Chinese Journal of Geriatrics

在线全文

学校读者我要写书评

暂无评论

Chinese Nursing Research 2017年第4期4卷 201-206页

作者： Chi-Chen Zhang Rui-Fang zhu Hui-Ning Zhao zhen-zhen Jin Feng-Ru Yan Xiao zheng Xiao-Jie Pan School of Management Shanxi Medical University Taiyuan Shanxi 030001 China Shanxi Medical University First Hospital of Shanxi Medical University Taiyuan Shanxi 030001 China School of Public Health Shanxi Medical University Taiyuan Shanxi 030001 China

Objective: To investigate the research hotspots and development trends of Chinese geriatric medicine by analyzing the high-frequency keywords, core authors, research institutions and their collaborations in papers published in the Chinese Journal of ***: Bibliometric methods and information visualization software(CiteSpace Ⅲ) were used to analyze the following 3 aspects: keywords, institutions and ***: Overall, the number of papers published in the Chinese Journal of Geriatrics grew between 1994 and 2015. The top 3 institutions with the greatest numbers of published papers were Beijing Hospital,People's Liberation Army General Hospital and the Second Xiangya Hospital of Central South *** authors with high productivity were Pulin Yu, Jianye Wang and Xiaoying Li. The terms "Diabetes","hypertension" and "myocardial infarction" were hotspot words that drew sustained attention in this ***: Research on geriatric medicine is growing steadily in China. Hospitals and teaching hospitals are major contributors to publications. The collaboration of authors is more common within the same institutions or in the same regions. Clinical research is still the focus of current research. In the future, basic research should be strengthened, and collaborations between different institutions and regions should be promoted to achieve coordinated and integrated development in Chinese geriatric medicine.

关键词： Geriatric medicine Current research state Research hotspot CiteSpace Chinese Journal of Geriatrics

在线全文

学校读者我要写书评

暂无评论

媒体协同对网络舆情扩散的作用机制研究

数据分析与知识发现 2019年第2期3卷 65-71页

作者：梅妍霜朱恒民魏静南京邮电大学管理学院南京210003

【目的】研究媒体协同在话题传播中的作用机制,及其在引导和控制舆情话题传播方面的应用。【方法】采用模拟仿真方法,构建媒体协同作用下的舆情话题传播模型,分析发挥协同作用的媒体,及其作用时间点和作用时长对舆情话题传播的影响机制... 详细信息

【目的】研究媒体协同在话题传播中的作用机制,及其在引导和控制舆情话题传播方面的应用。【方法】采用模拟仿真方法,构建媒体协同作用下的舆情话题传播模型,分析发挥协同作用的媒体,及其作用时间点和作用时长对舆情话题传播的影响机制。【结果】仿真结果表明,相对于单个媒体,多个媒体构建的协作网络对话题传播有更强的促进作用,并且受媒体介入时间和媒体作用时长影响。【局限】仿真实验中,网民传播舆情的载体网络虽是现实网络,但是媒体协作网络和话题传播数据均来自于模拟仿真。【结论】媒体之间的协作关系是话题传播中媒体的重要表现形式,合理利用其协同作用有利于科学、高效地控制和引导舆情话题的传播。

关键词：网络舆情媒体协作网络信息扩散话题传播

Usefulness of dobutamine stress myocardial contrast echocardiography for assessing coronary artery disease

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2005年第21期118卷 1766-1772页

作者： GUO Shi-zun SHU Xian-hong PAN Cui-zhen LI Yan-lin GE Jun-bo CHEN Hao-zhu Institute of Cardiovascular Diseases Zhongshan Hospital Fudan University Shanghai 200032 China

Background Quantitatively assessing myocardial perfusion and its reserve is of great importance for the diagnosis and stratification of patients with coronary artery disease （ CAD）, and represents an important goal of myocardial contrast echocardiography. In this study we sought to test the usefulness of low dose dobutamine stress real-time myocardial contrast echocardiography （RT-MCE） in the assessment of CAD, and to explore the relationship between perfusion reserve and contractile reserve. Methods Twenty-six patients with suspected or clinical diagnosed CAD were enrolled and underwent RT-MCE at baseline and under low dose dobutamine stress, and subsequent coronary angiography. RT-MCE images were analyzed quantitatively from microbubble replenishment curves for myocardial perfusion and its reserve. Results At baseline, significant differences in beta （0.28± 0. 12, 0. 25± 0. 09, 0.22 ± 0. 06, 0. 20± 0.07 respectively, P 〈0. 01） and A x beta （1.37 ±0. 46, 1.28±0. 47, 1. 13 ±0. 37, 0.91±0. 32, respectively, P 〈0. 01 ） were observed among four segment groups with graded coronary artery stenosis severity （normal; 30% -69% stenosis; 70% -90% stenosis; and beyond 90% stenosis） , but not observed in parameter A. When under stress, significant differences in A （5.73 ± 1.28, 5.63 ± 1.01,4.96 ±0.81,4.57 _＋0.62, respectively, P〈0.01）, beta （0.67 ±0. 17, 0.55 ±0. 19, 0.32 ±0. 13, 0.25 ±0.08, respectively, P 〈0.01） and A x beta （3.81 ± 1.20, 3. 11±1.17, 1.59 ±0. 82, 1. 12 _＋0. 37, respectively, P 〈0. 01 ） were observed among the formerly mentioned groups. Graded decreases in A reserve （ 1.20 ±0. 53, 1.11 ±0. 16, 0.98 ±0. 12, 0. 99 ±0.13, respectively, P〈0.01）, beta reserve （2.65 ±1.07, 2. 32±0.82, 1.44±0.40, 1.29±0.34, respectively, P〈0.01） and A xbeta reserve （3.05 ± 1.63, 2.59 ±1.01, 1.42 ±0.44, 1.27±0.34, respectively, P 〈 0. 01 ） could also be observed with increasing coronary stenosis severity. In five segments groups scored by WMS （ 1 - 5 ） , concordance between contracti

关键词： echocardiography contrast media coronary disease myocardial reperfusion dobutamine

Diesel Pollution Biodegradation: Synergetic Effect of Mycobacterium and Filamentous Fungi

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2008年第3期21卷 181-187页

作者： You-QING LI HONG-FANG LIU zhen-LE TIAN LI-HUA zhu YING-HUI WU HE-QING TANG Department of Chemistry Huazhong University of Science and Technology Wuhan 430074 Hubei China

Objective To biodegrade the diesel pollution in aqueous solution inoculated with Mycobacterium and filamentous fungi. Methods Bacteria sampled from petroleum hydrocarbons contaminated sites in Karamay Oilfield were isolated and identified as Mycobacterium hyalinum （MH） and cladosporium. Spectrophotometry and gas chromatography （GC） were used to analyze of the residual concentrations of diesel oil and its biodegradation products. Results From the GC data, the values of apparent biodegradation ratio of the bacterial strain MH to diesel oil were close to those obtained in the control experiments. Moreover, the number of MH did not increase with degradation time. However, by using n-octadecane instead of diesel oil, the real biotic degradation ratio increased to 20.9% over 5 days of degradation. Cladosporium strongly biodegraded diesel oil with a real degradation ratio of up to 34% after 5 days treatment. When the two strains were used simultaneously, a significant synergistic effect between them resulted in almost complete degradation of diesel oil, achieving a total diesel removal of 99% over 5 days of treatment, in which one part of about 80% and another part of about 19% were attributed to biotic and abiotic processes, respectively. Conclusion The observed synergistic effect was closely related to the aromatics-degrading ability of Cladosporium, which favored the growth of MH and promoted the bioavailability of diesel oil

关键词： Biodegradation Diesel Synergistic effect Mycobacterium hyalinum Fungi

在线全文

学校读者我要写书评

暂无评论

一种基于改进PSO算法的结构损伤识别方法

振动与冲击 2012年第5期31卷 17-20页

作者：陈震朱军华余岭华北水利水电学院土木与交通学院郑州450011 暨南大学力学与土木工程系广州510632

根据"结构损伤发生在局部"这一信息特征,在粒子群算法中引入零变异率系数,提出一种改进的粒子群结构损伤识别方法。两层刚架单损伤数值仿真研究结果表明:与普通粒子群算法相比,所提出的方法具有收敛速度快、识别结果准确、抗噪能力较强... 详细信息

根据"结构损伤发生在局部"这一信息特征,在粒子群算法中引入零变异率系数,提出一种改进的粒子群结构损伤识别方法。两层刚架单损伤数值仿真研究结果表明:与普通粒子群算法相比,所提出的方法具有收敛速度快、识别结果准确、抗噪能力较强及受种群数影响小的特点,这些优点对于将PSO应用于复杂结构的损伤诊断有着重要意义。

关键词：损伤检测粒子群算法约束优化零变异率系数

Children with infectious pneumonia caused by Ralstonia insidiosa:A case report

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2023年第9期11卷 2002-2008页

作者： Shuang-zhu Lin mei-Jia Qian Yan-Wei Wang Qian-Dui Chen Wan-Qi Wang Jia-Yi Li Rui-Tong Yang Xin-Yao Wang Chun-Yu Mu Kai Jiang Diagnosis and Treatment Center for Children Affiliated Hospital of Changchun University of Chinese MedicineChangchun 130021Jilin ProvinceChina Department of Imaging Affiliated Hospital of Changchun University of Chinese MedicineChangchun 130021Jilin ProvinceChina College of Integrated Chinese and Western Medicine Changchun University of Chinese MedicineChangchun 130117Jilin ProvinceChina College of Traditional Chinese Medicine Changchun University of Chinese MedicineChangchun 130117Jilin ProvinceChina

BACKGROUND Ralstonia is a Gram-negative non-fermentative bacterium widespread in nature,and includes four species,Ralstonia pickettii,Ralstonia solanacearum,Ralstonia mannitolilytica,and Ralstonia insidiosa,which were proposed in *** is mainly found in the external water environment,including municipal and medical water purification *** bacterium has low toxicity and is a conditional *** has been reported in recent years that infections due to Ralstonia are *** studies have shown that most cases of infection are caused by Ralstonia pickettii,a few by Ralstonia mannitolilytica,and infections caused by Ralstonia insidiosa are *** SUMMARY A 2-year-old Chinese child suffered from intermittent fever and cough for 20 d and was admitted to hospital with bronchial *** and alveolar lavage fluid culture confirmed Ralstonia insidiosa *** infection was well controlled after treatment with meropenem and *** Ralstonia infections are increasing,and we report a rare case of Ralstonia insidiosa infection in a *** should be vigilant about Ralstonia infections.

关键词： Children Infections Ralstonia insidiosa Pneumonia Treatment Case report

尼龙6/粘土与聚乙烯醇共混物中尼龙6的晶型转变

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

高分子材料科学与工程 2010年第8期26卷 42-45页

作者：崔莉叶正涛朱平新型纺织材料绿色加工及其功能化教育部重点实验室(武汉科技学院) 湖北武汉430073

主要研究了在尼龙6/粘土(NYC)与聚乙烯醇(PVA)共混复合物中尼龙6的晶型转变。在差示扫描量热(DSC)和X射线衍射的表征中发现,当PVA的含量小于16.7%时,PVA的α晶型消失。随着NYC/PVA体系中NYC含量的增加,原来存在于NYC中尼龙6主要的γ晶... 详细信息

主要研究了在尼龙6/粘土(NYC)与聚乙烯醇(PVA)共混复合物中尼龙6的晶型转变。在差示扫描量热(DSC)和X射线衍射的表征中发现,当PVA的含量小于16.7%时,PVA的α晶型消失。随着NYC/PVA体系中NYC含量的增加,原来存在于NYC中尼龙6主要的γ晶型逐渐转变为α晶型;当PVA的含量等于或大于50%时,在NYC/PVA体系中只存在α晶型的尼龙6结晶。用扫描电镜(SEM)进一步分析经离子束刻蚀的NYC/PVA样品发现,随PVA含量的增加所产生尼龙6晶型的转变现象,主要是由粘土迁移行为造成的。

关键词：晶型聚乙烯醇尼龙6

单原子Cr、Fe和Ni催化乙炔环三聚反应机理研究

在线全文

学校读者我要写书评

暂无评论

分子催化 2021年第2期35卷 158-165页

作者：朱文闻刘振上海石化工业学校上海201512 江苏大学化学化工学院江苏镇江212013 华东理工大学化工学院上海200237

应用密度泛函理论(DFT)研究了Cr、Fe和Ni3种金属原子催化乙炔环三聚生成苯的反应机理.结果表明,Cr、Fe和Ni催化体系均表现出自旋翻转现象, Cr原子催化乙炔环三聚过程在自旋七重态和五重态势能面上进行,速率控制步骤为形成铬金属七元环;F... 详细信息

应用密度泛函理论(DFT)研究了Cr、Fe和Ni3种金属原子催化乙炔环三聚生成苯的反应机理.结果表明,Cr、Fe和Ni催化体系均表现出自旋翻转现象, Cr原子催化乙炔环三聚过程在自旋七重态和五重态势能面上进行,速率控制步骤为形成铬金属七元环;Fe和Ni催化体系的速率控制步骤为两分子乙炔耦合过程. Cr催化体系表现出远高于Fe和Ni催化体系的活性,是乙炔环三聚的优选催化体系.

关键词： DFT 乙炔环三聚反应机理 TOF