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SiO_2.载磷钨杂多酸催化的甲苯与乙酸酐酰化反应

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燃料化学学报 2005年第5期33卷 622-625页

作者：胡拖平秦张峰王建国中国科学院山西煤炭化学研究所煤转化国家重点实验室

以SiO2.载12.磷钨酸(PW)为催化剂,对甲苯与乙酸酐(AA)的酰化反应进行了研究。采用XRD、BET、TGA和NH3-TPD等对PW/SiO2.化剂进行了表征。结果表明,PW负载量及焙烧温度对PW/SiO2.酸性、PW在SiO2.的分散状态以及酰化催化活性有明显的... 详细信息

以SiO2.载12.磷钨酸(PW)为催化剂,对甲苯与乙酸酐(AA)的酰化反应进行了研究。采用XRD、BET、TGA和NH3-TPD等对PW/SiO2.化剂进行了表征。结果表明,PW负载量及焙烧温度对PW/SiO2.酸性、PW在SiO2.的分散状态以及酰化催化活性有明显的影响。PW的负载量40%(按质量计)、焙烧温度300℃制备的PW(40%)/SiO2.化剂,其PW在载体表面的分散度好,酸量及酸强度适宜,对甲苯与乙酸酐的酰化反应具有较高的催化活性。在130℃,催化剂/乙酸酐(质量比)2.2.,催化反应效果最佳。

关键词：杂多酸 12.磷钨酸二氧化硅甲苯乙酸酐酰化反应

氧化还原预处理对一氧化碳低温氧化Pd/CeO_2.iO_2.化剂性能的影响

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燃料化学学报 2004年第6期32卷 729-733页

作者：朱华青秦张峰王建国中国科学院山西煤炭化学研究所煤转化国家重点实验室

研究了氧化还原预处理对溶胶凝胶法制备的CeO2.TiO2.合氧化物负载Pd催化剂上CO低温氧化性能的影响,并对催化剂的稳定性进行了考察。H2.TPR结果表明,83℃的耗氢峰是PdO和载体中CeO2.同还原的结果,高温还原后Pd与载体之间相互作用加强... 详细信息

研究了氧化还原预处理对溶胶凝胶法制备的CeO2.TiO2.合氧化物负载Pd催化剂上CO低温氧化性能的影响,并对催化剂的稳定性进行了考察。H2.TPR结果表明,83℃的耗氢峰是PdO和载体中CeO2.同还原的结果,高温还原后Pd与载体之间相互作用加强。经高温氧化(500℃)低温还原(150℃)预处理的催化剂CO低温氧化活性最好,在反应气组成为0.5%CO+1.6%O2.6.0%N2.Ar,空速为30000mL·g-1·h-1,程序升温反应显示CO完全转化温度为48℃,这种预处理方式能够形成适宜的载体与金属间相互作用。稳定性实验在室温下进行,反应气组成为0.6%CO+14.7%O2.55.3%N2.Ar,Pd CeO2.TiO2.化剂具有较好的低温反应稳定性,100%CO转化率可持续12.。

关键词：一氧化碳低温氧化 Pd催化剂 CeO2.TiO2.合氧化物溶胶-凝胶

C_5烷烃分子在AlPO_4-5分子筛中吸附的分子模拟研究

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燃料化学学报 2004年第5期32卷 569-572页

作者：刘洁翔董梅秦张峰王建国中国科学院山西煤炭化学研究所煤转化国家重点实验室

采用分子水平计算机模拟方法研究了环戊烷、正戊烷和2.甲基丁烷在AlPO4 5分子筛中的吸附,得到了有关吸附平衡常数、吸附热、吸附等温线以及平均势能等。结果表明,在373K,2.甲基丁烷的饱和吸附量高于其他两种异构体;473K,环戊烷的饱和吸... 详细信息

采用分子水平计算机模拟方法研究了环戊烷、正戊烷和2.甲基丁烷在AlPO4 5分子筛中的吸附,得到了有关吸附平衡常数、吸附热、吸附等温线以及平均势能等。结果表明,在373K,2.甲基丁烷的饱和吸附量高于其他两种异构体;473K,环戊烷的饱和吸附量高于其他两种异构体;573K,在所测试的压力范围内,环戊烷的吸附量都高于其他两种异构体,2.甲基丁烷的吸附量高于正戊烷。C5烷烃分子在AlPO4 5中吸附量的不同是由于他们在分子筛中的排列方式不同而引起的。低吸附量时C5烷烃分子平均势能不随吸附量变化;高吸附量时平均势能随着吸附量的增加而降低;而2.甲基丁烷和环戊烷分子的平均势能变化更加明显。

关键词：分子筛 AlPO4—5 C5 吸附分子模拟

基于GNSS散射信号陆地高度计的建模与分析

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系统仿真学报 2009年第10期21卷 2810-2814页

作者：张建军袁洪王宪中国科学院光电研究院北京100190 中国科学院研究生院北京100190 平顶山工学院平顶山467044

全球卫星导航系统(Global Navigation Satellite System,GNSS)的散射信号作为一项新的遥感技术日益受到关注,目前已经成功的应用到海洋高度测量中,但由于陆地表面特性复杂,使基于GNSS的陆地表面高度计的设计一直是个难点。根据GPS信号... 详细信息

全球卫星导航系统(Global Navigation Satellite System,GNSS)的散射信号作为一项新的遥感技术日益受到关注,目前已经成功的应用到海洋高度测量中,但由于陆地表面特性复杂,使基于GNSS的陆地表面高度计的设计一直是个难点。根据GPS信号的特点,推导了GPS地面散射回波信号的数学方程,建立了能反映陆地表面特性的GNSS-R双站雷达模型,从而设计了以GPS卫星作为照射源,接收机置于飞行器上,利用GPS散射信号测量陆地上空飞行器高度的仿真系统。通过对仿真结果的分析,验证了模型的有效性,也为后续的GNSS-R陆地高度计的优化设计提供了依据。

关键词： GNSS—R 散射信号陆地表面高度计

Changes of cell morphology and cytoskeleton organization in a hypogeomagnetic field

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Changes of cell morphology and cytoskeleton organization in ...

3D Nerve: A Three-Dimensional Reconstruction System for Peripheral Nerves

2.11年空间生命与生命起源暨航天医学工程学术研讨会

作者： Wei-chuan Mo~(1,3),Dong-liang wang~2.Zi-jian {2.~(1,3),Ying Liu~(1,3), Rong-qiao He~(1,3) 1 State Key Laboratory of Brain and Cognitive Science,Institute of Biophysics,chinese academy of sciences,15 Datun Road,Chaoyang District,beijing 100101,china 2.National Center for Nanoscience and technology,chinese academy of sciences,11 Zhongguancun Beiyitiao,Haidian District,beijing 100190,china 3 graduate university of the chinese academy of sciences,19 A Yuquan Road,beijing,100049,china.

＜正＞Hypogeomagnetic field（HGMF）refers to a geomagnetic field（GMF）eliminated environment,which is one of the characteristic environmental factor in outer space. Recent studies have shown that hypogeomagnetic exposures exhibit adverse effects on embryonic development and animal ***,astronauts are under potential risks due to the hypogeomagnetic aerospace during the space missions. However,the mechanisms of the HGMF effects remain unclear.

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3D Nerve: A Three-Dimensional Reconstruction System for Peri...

A multicenter uroflowmetry study of healthy women in china

2.08 IEEE International Symposium on IT in Medicine and Education(ITME 2.08)

作者： Ping Hu 1 2.Shuisheng Xie 1 2.Juan Ge 1 2.Liyan Liu 1 2.Shaorong wang 1 2.Fucang Jia 1 2.Zongkai Lin 1 2.Hua Li 1 2.Kuo Sun 3 Zenggan Chen 3 jian {2. 3 1.National Research Center for Intelligent Computing Systems Institute of Computing technology chinese academy of sciences beijing 100190 china 2.graduate university of chinese academy of sciences beijing 100049 china 3.Zhongshan Hospital Fudan university Shanghai 2.0032.china

Repair and regeneration of injured peripheral nerves have always been a focus in the field of *** nerve atlas contains only two-dimensional information and can’t display the real cross and recombination process of nerve bundles in its whole *** solve this problem,a system,3D Nerve,is proposed for the 3D reconstruction of peripheral *** image registration,image segmentation,contour correspondence and surface reconstruction process,this system successfully represents the topographic anatomy of every nerve fascicle and its relationship with the nicety localization information of sense fibers and motor ones in arbitrary *** is a great help for clinical peripheral nerve repair and 3D peripheral nerve teaching.

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chinese Medical Journal 2024年第10期137卷 1225-1227页

作者： Xiaodong Liu Lingfeng Meng Jiawen wang Tianming Ma Benkang Shi Hai Huang Qingwei wang Min Chen Limin Liao Hong Shen Zhongqing Wei Yuansong Xiao Tiejun Pan {2. Ren Peng zhang Xiaojun Tian Yaoguang zhang Department of Urology Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China graduate school of Peking Union Medical College Beijing 100730China Department of Urology Qilu HospitalShandong UniversityJinanShandong 250013China Department of Urology SUN YAT-SEN Memorial HospitalGuangzhouGuangdong 510235China Department of Urology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan 450003China Department of Urology Tongji HospitalTongji Medical College of Huazhong University of Science and TechnologyWuhanHubei 430030China Department of Urology China Rehabilitation Research CenterBeijing 100068China Department of Urology West China HospitalChengduSichuan 610041China Department of Urology The Second Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu 210011China Department of Urology General Hospital of Southern Theatre CommandGuangzhouGuangdong 510010China Department of Urology General Hospital of Central Theatre CommandWuhanHubei 430071China Department of Urology China-Japan Friendship HospitalBeijing 100029China Department of Urology Beijing Chao-Yang HospitalBeijing 100027China Department of Urology Peking University Third HospitalBeijing 100191China

Uroflowmetry is an uroflow measurement technique used to record the voided volume(VV)and flow rate,which can help clinicians objectively evaluate lower urinary tract ***,few uroflowmetry studies have focused on the female population,[1]especially on the uroflow curve standard ***,we sought to establish dependable uroflow reference values and nomograms for chinese women and to evaluate the relationship between uroflow patterns and demographic data.

关键词： function. flowmetry analysis.

DEAD-box helicase 17(DDX17)protects cardiac function by promoting mitochondrial homeostasis in heart failure

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2774-2790页

作者： Mingjing Yan Junpeng Gao Ming Lan Que wang Yuan Cao Yuxuan Zheng Yao Yang Wenlin Li Xiaoxue Yu Xiuqing Huang Lin Dou Bing Liu Junmeng Liu Hongqiang Cheng Kunfu Ouyang Kun Xu Shenghui Sun Jin Liu Weiqing Tang Xiyue zhang Yong Man Liang Sun {2.ping Cai Qing He Fuchou Tang {2. Li Tao Shen The Key Laboratory of Geriatrics Beijing Institute of GeriatricsInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing Hospital/National Center of Gerontology of National Health CommissionBeijing 100730China Peking university Fifth school of Clinical Medicine Beijing 100730China Department of Laboratory Medicine Huashan HospitalShanghai Medical CollegeFudan UniversityShanghai 200040China Biomedical Pioneering Innovation Center School of Life SciencesPeking UniversityBeijing 100871China Emergency Center Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Cardiology Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China graduate school of Peking Union Medical College Beijing 100730China Department of Health Care Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China Peking-Tsinghua Center for Life sciences Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China Department of Pathology and Pathophysiology and Department of Cardiology at Sir Run Run Shaw Hospital Zhejiang University School of MedicineHangzhou 310058China Department of Cardiovascular Surgery Peking University Shenzhen HospitalShenzhen 518036China Experimental technology Center for Life sciences at {2. Normal university Beijing 100875China

DEAD-box helicase 17(DDX17)is a typical member of the DEAD-box family with transcriptional cofactor *** DDX17 is abundantly expressed in the myocardium,its role in heart is not fully *** generated cardiomyocyte-specific Ddx17-knockout mice(Ddx17-cKO),cardiomyocyte-specific Ddx17 transgenic mice(Ddx17-Tg),and various models of cardiomyocyte injury and heart failure(HF).DDX17 is downregulated in the myocardium of mouse models of heart failure and cardiomyocyte ***-specific knockout of Ddx17 promotes autophagic flux blockage and cardiomyocyte apoptosis,leading to progressive cardiac dysfunction,maladaptive remodeling and progression to heart *** of DDX17 expression in cardiomyocytes protects cardiac function under pathological *** studies showed that DDX17 can bind to the transcriptional repressor B-cell lymphoma 6(BCL6)and inhibit the expression of dynamin-related protein 1(DRP1).When DDX17 expression is reduced,transcriptional repression of BCL6 is attenuated,leading to increased DRP1 expression and mitochondrial fission,which in turn leads to impaired mitochondrial homeostasis and heart *** also investigated the correlation of DDX17 expression with cardiac function and DRP1 expression in myocardial biopsy samples from patients with heart *** findings suggest that DDX17 protects cardiac function by promoting mitochondrial homeostasis through the BCL6-DRP1 pathway in heart failure.

关键词： DDX17 homeostasis cardiac

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喀斯特生态系统服务研究进展与展望

贵州师范大学学报（自然科学版） 2024年第5期42卷 77-84,105页

作者：王佳斌彭建张日玄徐子涵刘焱序北京大学深圳研究生院城市规划与设计学院广东深圳518055 北京大学城市与环境学院/自然资源部生态系统一体化修复与可持续利用工程技术创新中心北京100871 北京林业大学水土保持学院北京100083 北京师范大学地理科学学部地表过程与资源生态国家重点实验室北京100875

喀斯特生态系统脆弱,密集的人类活动导致了我国喀斯特地区生态系统的退化,影响了区域生态系统服务供给和人类福祉提升。论文概述了当前喀斯特生态系统服务领域的发文变化,并总结了三大热点研究方向:喀斯特生态系统服务估值及其时空变化... 详细信息

喀斯特生态系统脆弱,密集的人类活动导致了我国喀斯特地区生态系统的退化,影响了区域生态系统服务供给和人类福祉提升。论文概述了当前喀斯特生态系统服务领域的发文变化,并总结了三大热点研究方向:喀斯特生态系统服务估值及其时空变化;喀斯特生态系统服务社会-生态驱动因素;喀斯特生态系统服务权衡协同关系。同时,提出了四大未来重点研究方向,包括基于地质-社会-生态条件选取关键喀斯特生态系统服务,喀斯特生态系统服务垂向流动,喀斯特生态系统服务与人类福祉级联,以及生态工程对喀斯特生态系统服务的影响。

关键词：喀斯特生态系统服务垂向流人类福祉生态工程

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