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高校中文医学期刊出版伦理制度建设现况及分析

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首都医科大学学报 2025年第1期46卷 161-166页

作者：闫红高健黄芳张建军《首都医科大学学报》编辑部北京100069

目的调查高校中文医学期刊出版伦理制度建设现状,探讨高校中文医学期刊出版伦理制度建设方面存在的问题并提出相应的建议。方法以2023年版《中国科技期刊引证报告(核心版)自然科学卷》中的55种医药大学学报类期刊为研究对象,通过期刊官... 详细信息

目的调查高校中文医学期刊出版伦理制度建设现状,探讨高校中文医学期刊出版伦理制度建设方面存在的问题并提出相应的建议。方法以2023年版《中国科技期刊引证报告(核心版)自然科学卷》中的55种医药大学学报类期刊为研究对象,通过期刊官网调查其出版伦理制度建设情况。结果仅18种期刊在其官网中有明确的出版伦理栏目,涵盖作者、审稿人、编辑、出版者有关的出版伦理制度,而其他期刊只在各自官网发布的投稿指南、同行评议、相关声明中提及作者、审稿人、编辑、出版者有关的出版伦理制度,且涵盖不全,出版流程不透明。结论高校中文医学期刊出版伦理制度建设尚不完善,应完善出版伦理制度规范,加强学术不端行为的防范与处理;加强出版伦理制度的宣传,增强作者的诚信意识;推进出版流程透明化,加强出版各流程的监督预警。

关键词：医学科技期刊出版伦理学术不端行为诚信意识

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Analysis of unmanned aerial vehicle navigation and height control system based on GPS

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Journal of Systems Engineering and Electronics 2010年第4期21卷 643-649页

作者： jianjun zhang Hong Yuan China Academy of Space Technology Beijing 100094 E R. China Academy of Opto-Electronics Chinese Academy of Sciences Beijing 100190 P. R. China

According to the characteristic of global positioning system（GPS） reflection signals,a GPS delay mapping receiver system scheme is put forward,which not only satisfies the unmanned aerial vehicle（UAV） guidance localization but also realizes height measurement.A code delay algorithm is put forward,which processes the direct and land reflected signal and outputs the navigation data and specular *** GPS terrain reflected echo signal mathematical equation is *** reflecting signal area,when the GPS signal passes the land,is *** height survey model reflected land surface characteristic is established.A simulation system which carries guidance localization of the UAV and the height measuring control through the GPS direct signal and the land reflected signal is designed,taken the GPS satellite as the illumination source,the receiver is put on the *** the UAV guidance signal,the GPS reflection signal and receiver＇s parallel processing are *** parallel processing reduces UAV＇s payload and raises system＇s operating *** simulation results confirms the validity of the model and also provides the basis for the UAV＇s optimization design.

关键词： height measuring global positioning system(GPS) reflected signal delay mapping receiver unmanned aerial vehicle(UAV).

Hippocampal ultrastructural changes and apoptotic cell death in rats following endurance training and acute exhaustive exercise

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Neural Regeneration Research 2008年第6期3卷 679-682页

作者： jianjun zhang Physical Education College Zhengzhou University Zhengzhou 450044 Henan Province China

BACKGROUND： Exhaustive exercise can lead to apoptosis of skeletal muscle cells and myocardial cells as a result of pathological changes in the corresponding cellular ultrastructure. It is hypothesized that such changes could also occur in neurons. OBJECTIVE： To observe brain cell apoptosis and ultrastructural changes in hippocampal neurons in rats following endurance training and acute exhaustive exercise. DESIGN, TIME AND SETTING： A randomized, controlled, morphological analysis was performed at the Medical Laboratory Center of Zhengzhou University between July and November 2007. MATERIALS： Forty male, 8-week-old, Sprague Dawley rats were included in this study. METHODS： Endurance training consisted of treadmill running once a day, 6 days a week, for 4. weeks. For acute exhaustive exercise, graded treadmill running was conducted. Rats were exposed to exercise at an increasing speed （10 m/min, increasing to 20 and 36 m/min for moderate- and high-intensity exhaustive exercise, respectively, and then was continued until exhaustion）. A total of 40 rats were evenly distributed into the following 4. groups： Group A rats were not exercised; Group B rats were not trained but sacrificed 24 hours after acute exhaustive treadmill running exercise; Group C-rats were subjected to endurance training and sacrificed immediately after acute exhaustive treadmill running exercise; Group D rats were subjected to endurance training and sacrificed 24 hours after acute exhaustive treadmill running exercise. MAIN OUTCOME MEASURES： Apoptotic cell death was detected by the TUNEL method and hippocampal neuronal ultrastructural change was observed through using transmission electron microscopy. RESULTS： All 40 rats were included in the final analysis. Subsequent to exhaustive exercise, rat cerebral cortex and hippocampal neurons appeared contracted and degenerated. In addition, high amount of lipofuscin was visible in the hippocampal region, Necrotic neurons encased by glial cells appeared in

关键词： endurance training exhaustive exercise apoptosis pyramidal neuron mitochondrion

Bifunctional photocatalyst for H_(2) production and high-value product synthesis

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Journal of Materials Science & Technology 2023年第11期142卷 121-123页

作者： jianjun zhang Yao Le Yong zhang School of Chemistry Chemical Engineering and BiotechnologyNanyang Technological University21 Nanyang LinkSingapore 637371Singapore College of Architecture and Materials Engineering Hubei University of EducationWuhan 430205China School of Chemistry and Chemical Engineering Hubei Polytechnic UniversityHuangshi 435003China

Recently,a bifunctional CdS/MoO_(2)/MoS_(2) photocatalyst has been reported for coupling hydrogen production and pyruvic acid ***_(2) and MoO_(2),which are synthesized in one step,facilitate the bifunctional integration of photocatalytic hydrogen evolution and pyruvic acid synthesis by accepting photogen-erated electrons and holes,*** work inspires the new idea of coupling hydrogen production with selective organic synthesis to obtain green hydrogen and high-value products.

关键词： CdS Hollow sphere Dual cocatalysts Hydrogen evolution Organic synthesis

Effects of oxygen and carbon on the magnetic properties and microstructure of Sm_2Co_(17) permanent magnets

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Rare Metals 2007年第4期26卷 299-304页

作者： TIAN jianjun zhang Shengen QU Xuanhui School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The research on the sintered Sm2Co17 permanent magnets prepared by metal injection molding is still at the exploratory stage. Carbon and oxygen are two key factors that influence the magnetic properties. In this article, the effects of oxygen and carbon on the properties and microstructure of the magnets have been studied. The results indicate that oxygen consumes the effective Sm content of the magnets and forms Sm2O3-the non-magnetism phase, which result in the deterioration of the magnetic properties. Besides, the magnetic properties decrease in evidence with increasing carbon content. The main factor that affects the magnetic properties is the deterioration of the microstructure of the magnets. The Sm（Co, Cu）5 phase decreases, whereas the cell size increases with the increase of the carbon content. When the carbon content is above 0.43 wt.%, the Sm（Co, Cu）5 phase is not enough to form a uniform cellular microstructure. Thus the magnetic properties disappear. ZrC is detected in the magnets by XRD when the carbon content is above 0.21 wt.%. ZrC also reduces the properties of the magnets.

关键词： permanent magnets oxygen carbon magnetic properties microstructure

Research on assessment method of intrasystem and intersystem of the global navigation satellite system

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Science China(Technological Sciences) 2015年第10期58卷 1672-1681页

作者： zhang jianjun XUE Ming XIE Jun China Academy of Space Technology Qian Xuesen Laboratory of Space Technology

The global navigation satellite system(GNSS) has become an important space infrastructure. Following GPS and GLONASS, Europe and China have been building their own global navigation satellite system, respectively, GALILEO and Compass. In order to consolidate the leadership of GPS in the globe, United States is gradually upgrading the traditional GPS. Simultaneously, Russia is also intensively restoring full performance of GLONASS. With the advancement of international satellite navigation system, satellite navigation frequency resources are already in short supply, and the design and use of the navigation signals are more sophisticated and complex due to commercial, disaster relief and other reasons. Since there may be many navigation signals in the same basic bandwidth, the coexistence of multiple systems and the combined application make intersystem mutual interference become the focus research. Under this background, the satellite navigation system mutual interference evaluation system needs to be established urgently to meet and support the compatibility and interoperability of the GNSS system. In the paper, through the performance analysis of the GNSS signal acquisition, carrier tracking, data demodulation and code tracking, the equivalent carrier to noise ratio model based on spectrum isolation coefficient is established, and the theoretical system of the GNSS signal mutual interference is proposed according to the mechanism, and the mutual interference of GPS, GALILEO and Compass system is analyzed and assessed.

关键词： GNSS intrasystem interference intersystem interference equivalent carrier to noise ratio

PEI/PEEK复合材料的熔融沉积制备及其摩擦磨损性能

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润滑与密封 2025年第2期50卷 112-120页

作者：阮俊飞裴先强车清论张建军青岛理工大学机械与汽车工程学院山东青岛266520 中国科学院兰州化学物理研究所固体润滑国家重点实验室甘肃兰州730000

聚合物材料的耐温性能对其摩擦磨损性能具有重要的影响。为改善聚醚醚酮(PEEK)的耐温性能,采用聚醚酰亚胺(PEI)对其进行改性。利用熔融沉积成型制备聚醚酰亚胺/聚醚醚酮(PEI/PEEK)复合材料,考察PEI的引入对PEEK热学性能的影响,以及PEI... 详细信息

聚合物材料的耐温性能对其摩擦磨损性能具有重要的影响。为改善聚醚醚酮(PEEK)的耐温性能,采用聚醚酰亚胺(PEI)对其进行改性。利用熔融沉积成型制备聚醚酰亚胺/聚醚醚酮(PEI/PEEK)复合材料,考察PEI的引入对PEEK热学性能的影响,以及PEI含量对PEI/PEEK复合材料摩擦磨损性能的影响。研究表明:PEEK与PEI完全互溶,随着复合材料中PEI含量的增大,复合材料的玻璃化转变温度不断升高,且力学性能也不同程度地提高;当PEI质量分数为30%时复合材料表现出优异的力学性能。以复合材料力学性能为指标,获得优化的复合材料熔融沉积工艺,即喷嘴温度390℃,底板温度170℃。摩擦磨损性能测试发现,当PEI质量分数不超过30%时,复合材料的摩擦因数和磨损率较为稳定,而PEI质量分数超过30%后复合材料的摩擦因数和磨损率变化较大。

关键词：复合材料聚醚醚酮聚醚酰亚胺熔融沉积成型力学性能摩擦磨损

Preparation of pH-Responsive Doxorubicin Nanocapsules by Combining High-gravity Antisolvent Precipitation with In-situ Polymerization for Intracellular Anticancer Drug Delivery

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Chemical Research in Chinese Universities 2020年第5期36卷 927-933页

作者： LIU Jie CHEN Bo zhang jianjun College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029P.R.China State Key Laboratory of NBC Protection far Civilian Beijing 102205P.R.China

Owing to the low pH value in tumor and cancer cells,drug delivery systems based on pH-responsive polymer nanocarriers have been extensively explored for anticancer ***,we developed a pH-responsive doxonibicin(EXDX)nanocapsule(named as DNanoCapsule)prepared by combining in-situ polymerization teclinique with high-gravity antisolvent precipitation technique throngh an amphiphilic polymerized surface *** show an obvious spherical core-shell structure with a single DOX nanoparticle encapsulated in the polymer *** rate studies prove that the DNanoCapsules have robust dnig-release profiles under acidic environments due to the division of the pH-sensitive cross-linker,which triggers thecollapse of the polymer *** in vitro investigations demonstrated that the DNanoCapsules exhibited higli cellular uptake efficiency and cytotoxicity for both HeLa and MCF-7 cancer ***,this work may provide a promising strategy to design and develop various stimuli-responsive drug nanocapsules tor the treatment of cancer or other diseases.

关键词： pH-Responsive Nanocapsule In-situ polymerization High-gravity anti solvent precipitation Anticancer cheniotherapy

Bifurcation from the essential spectrum for an elliptic equation with general nonlinearities

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Science China Mathematics 2023年第10期66卷 2243-2260页

作者： jianjun zhang Xuexiu Zhong Huansong Zhou College of Mathematics and Statistics Chongqing Jiaotong UniversityChongqing 400074China South China Research Center for Applied Mathematics and Interdisciplinary Studies South China Normal UniversityGuangzhou 510631China Center for Mathematical Sciences and Department of Mathematics Wuhan University of TechnologyWuhan 430070China

In this paper,based on some prior estimates,we show that the essential spectrum λ=0 is a bifurcation point for a superlinear elliptic equation with only local conditions,which generalizes a series of earlier results ... 详细信息

关键词： elliptic equation bifurcation point essential spectrum