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Carbon,nitrogen and phosphorus stoichiometry in Pinus tabulaeformis forest ecosystems in warm temperate Shanxi Province,north China

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Journal of Forestry Research 2018年第6期29卷 1665-1673页

作者： Ning wang Fengzhen Fu Baitian wang ruijun wang College of Agronomy Heilongjiang Bayi Agricultural UniversityDaqing 163319HeilongjiangPeople’s Republic of China Daqing Forestry Bureau Daqing 163002HeilongjiangPeople’s Republic of China Soil and Water Conservation School Beijing Forestry UniversityBeijing 100083People’s Republic of China

Although carbon(C), nitrogen(N), and phosphorous(P) stoichiometric ratios are considered good indicators of nutrient excess/limitation and thus of ecosystem health, few reports have discussed the trends and the reciprocal effects of C:N:P stoichiometry in plant–litter–soil systems. The present study analyzed C:N:P ratios in four age groups of Chinese pine, Pinus tabulaeformis Carr., forests in Shanxi Province, China: plantation young forests(AY,<20 year-old); plantation middle-aged forests(AM, 21–30 year-old); natural young forests(NY,<30 year-old); and natural middle-aged forests(NM,31–50 year-old). The average C:N:P ratios calculated for tree, shrub, and herbaceous leaves, litter, and soil(0–100 cm) were generally higher in NY followed by NM,AM, and AY. C:N and C:P ratios were higher in litter than in leaves and soils, and reached higher values in the litter and leaves of young forests than in middle-aged forests;however, C:N and C:P ratios were higher in soils of middle-aged forests than in young forests. N:P ratios were higher in leaves than in litter and soils regardless of stand age; the consistent N:P<14 values found in all forests indicated N limitations. With plant leaves, C:P ratios were highest in trees, followed by herbs and shrubs, indicating a higher efficiency in tree leaf formation. C:N ratios decreased with increasing soil depth, whereas there was no trend for C:P and N:P ratios. C:N:P stoichiometry of forest foliage did not exhibit a consistent variation according to stand age. Research on the relationships between N:P, and P, N nutrient limits and the characteristics of vegetation nutrient adaptation need to be continued.

关键词： Pinus tabulaeformis Carr. Forest ecosystem Content of carbon Nitrogen and phosphorus Ecological stoichiometry Warm temperate zone China

Polysaccharide separation mechanism in polysulfone-Fe_3O_4 magnetic composite membranes

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Chinese Science Bulletin 2011年第18期56卷 1951-1956页

作者： wang ruijun CHEN Yan XIE HuiMing KAI GuiQing wang ZiYao PAN Jian School of Life Sciences Anhui University Hefei 230039 China Engineering Research Center of Bio-Process of Ministry of Education Hefei University of Technology Hefei 230009 China

Polysulfone (PSF)-Fe3O4 composite membranes were prepared by the phase-inversion process and their polysaccharide separation mechanism was explored using chondroitin sulfate (CS) and dextran. The mechanism was analyzed from constraints on the magnetic field and geometric deformation. It was found that variations in dextran rejection from 58% to 46% were mainly influenced by the geometric deformation of the composite membrane, while the magnetic field had a significant influence on variations in CS rejection from 82% to 35%. The results indicate that it is possible to continuously separate different types of polysaccharide with a composite membrane by adjusting the external magnetic field.

关键词：磁性复合膜 Fe3O4 分离机制多糖聚砜磁场约束几何变形硫酸软骨素

Effects of fragments on W-DLC films properties under boundary lubrication condition in the friction system

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China Welding 2018年第2期27卷 31-38页

作者： Zhan Hua wang ruijun Li Zhendong Xu Tianyang wang Weiping Chinese Academy of Agricultural Mechanization Sciences Beijing 100083 China Beijing Golden Wheel Special Machine Co. Ltd. Beijing 100083 China

Abstract Effects of film fragments in the friction system on friction and wear properties of tungsten doped diamond-like carbon films （W-DLC） were studied in the condition of boundary lubrication. It could be observed that the average friction coefficient was increased after introducing film fragments into the friction system, where these film fragments can accelerate the breaking of the extreme thin oil film which could separate two friction surfaces when the system is under boundary lubrication conditions. The increasing friction load can accelerate the friction ehenfieal reaction on the friction interface and lead to the crushing effect on film fragments, which decreased the friction coefficient of friction system. It was also found that the wear width, depth, and volume of the film increased by introducing film fragments and applying great load.

关键词： fragments W-DLC films friction coefficient friction load

Performance study of a complex thermal barrier functional coating with an electro-spark deposited burn-resistant layer

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China Welding 2019年第2期28卷 24-28页

作者： wang ruijun Xu Tianyang Ma Xiaobin Luo Zhiheng Chinese Academy of Agricultural Mechanization Sciences Beijing 100083China

It is necessary to develop burn-resistant and thermal barrier complex functional coatings on the titanium alloys surface due to the poor high temperature performance for titanium materials and the problem of“titanium fire”which is easily *** Aero Engines GmbH has developed a complex functional coating which has great performance of burn resistant and sealing,the coatings has already been applied on compressor blades and casing for aero-engines and showed great *** this study,the complex functional coating which is composed of an electro-spark deposited amorphous Ti40Zr25Ni3 burn-resistant layer and a high-energy plasma spraying prepared YSZ thermal barrier layer was prepared on titanium alloys *** the heat insulation ability,burn resistant performance and the bonding strength were *** experimental results showed that the interface between the coating and the matrix was typical metallurgical bonded,and the average bonding strength was 36.335 MPa;when the temperature of the flame on the one side of the specimen reached 600℃,the average insulated temperature of the coating samples was 70.67℃;when the flame temperature was 350℃,the titanium samples without the complex functional coatings were burned,while the samples with the coating showed great performance of burn resistant even when the temperature was 750℃.This indicates that the new functional coating has good heat-insulating and burn-resistant performance.

关键词： complex functional coatings burn resistance heat insulation

Species and Distribution Characteristics of Alien Invasive Plants in Garden Greenbelt of Shijiazhuang City

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Plant Diseases and Pests 2023年第4期14卷 38-43,47页

作者： Ruchun ZHANG Hongjun JIANG Henan MENG ruijun wang Institute of Geographical Sciences Hebei Academy of Sciences/Hebei Technology Innovation Center for Geographic Information ApplicationShijjazhuang 050011China

[Objectives]The paper was to investigate the garden greenbelt in 30 sample plots such as parks,roads,communities,*** Shijiazhuang City.[Methods]The species,abundance and frequency of weeds in the greenbelt of public gardens were recorded through point-line-surface investigation,and typical plants were sampled.[Results]There were 56 species of alien invasive plants in garden greenbelts of Shijiazhuang City,belonging to 44 genera and 20 *** terms of life form,herbaceous plants were absolutely dominant,accounting for 92.8%of the *** most alien invasive plants were native to America,accounting for 66.1%of the *** terms of introduction path,the plants introduced artificially and unintentionally accounted for almost *** species and quantity of alien invasive plants were related to the size of greenbelt area,the length of the build time of the surveyed plot,the composition structure of greenbelt and the level of green management and *** was larger distribution of alien invasive plants in the sample plots with large greenbelt area,long build time,herbaceous-dominated greenbelt and low level of green management and *** the 56 alien invasive plants,3 plants were *** the perspective of invasiveness,the alien invasive plants in the garden greenbelt of Shijiazhuang City could be divided into 5 levels:invasive alien species of malignant consequences,invasive alien species of severe consequences,invasive alien species of partial consequences,invasive alien species of average consequences,and invasive alien species to be observed.[Conclusions]This study will provide a reference for the prevention and control of alien plant invasion,and lay a foundation for the prevention and control of existing invasive plants.

关键词： Alien invasive plant Garden greenbelt Distribution characteristics Shijazhuang City Introduction path

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美国犯罪被害人政府补偿制度介评

环球法律评论 2009年第3期31卷 125-132页

作者：王瑞君山东大学威海分校法学院副教授、法学博士

在美国,自1965年加利福尼亚州率先通过《犯罪被害人政府补偿条例》以来,其他各州也相继引进了该制度。1984年联邦补偿法案的通过及自此开始的资金援助,推动了各州补偿制度的建立。至1992年,美国各州都建立了犯罪被害人政府补偿制度。美... 详细信息

在美国,自1965年加利福尼亚州率先通过《犯罪被害人政府补偿条例》以来,其他各州也相继引进了该制度。1984年联邦补偿法案的通过及自此开始的资金援助,推动了各州补偿制度的建立。至1992年,美国各州都建立了犯罪被害人政府补偿制度。美国犯罪被害人政府补偿涉及补偿理论依据、补偿的实质要件和程序运作、资金来源、争议解决等方面,是一个迄今仍充满挑战并不断发展的制度。

关键词：犯罪被害人政府补偿美国

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我国刑罚附随后果制度的完善

政治与法律 2018年第8期 92-106页

作者：王瑞君山东大学威海法学院山东威海264209

我国存在大量的包括"职业禁止""资格限制"等在内的非刑罚性禁止或限制措施,散见于不同层阶的制度,内容分散,标准不一,依据不明确,前置条件与后果的逻辑关联性不强,加上对受过刑罚的人员的个别价值评价性做法,使得受过刑罚处罚人员回归... 详细信息

我国存在大量的包括"职业禁止""资格限制"等在内的非刑罚性禁止或限制措施,散见于不同层阶的制度,内容分散,标准不一,依据不明确,前置条件与后果的逻辑关联性不强,加上对受过刑罚的人员的个别价值评价性做法,使得受过刑罚处罚人员回归社会面临许多难题。刑罚附随后果制度合理存在的价值基础应该是:在必要的预防前提下,尽可能地接纳受过刑罚的人回归社会。为此,整个社会要担负起拯救犯罪者、改造犯罪者并使其回归社会的义务,同时,有必要在国家层面对刑罚附随后果予以缓和与松绑,整体提升刑罚附随后果制度的设立层阶,体系性地构建刑罚附随后果制度,改进和优化其具体内容,合理地控制禁止和排斥的范围,理性地给予受过刑罚的人员以出路。

关键词：刑罚附随后果职业禁止资格刑价值基础制度优化

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论被害人责任的刑法意义

东岳论丛 2009年第12期30卷 149-154页

作者：王瑞君山东大学威海分校山东威海264209

我国对刑事责任的立法模式和学理界定,体现的是以犯罪人为中心的刑事责任归咎的基本立场,反映出我国刑事被害人学研究的不足及该领域研究成果与刑法的脱节,对司法实践的直接影响是办案人员对被害人责任的漠视或重视不足。因此,有必要反... 详细信息

我国对刑事责任的立法模式和学理界定,体现的是以犯罪人为中心的刑事责任归咎的基本立场,反映出我国刑事被害人学研究的不足及该领域研究成果与刑法的脱节,对司法实践的直接影响是办案人员对被害人责任的漠视或重视不足。因此,有必要反思现存刑事责任归咎模式,赋予刑事被害人责任刑法地位以影响对犯罪人的刑罚,当然,对被害人责任的程度应有所要求。

关键词：被害人责任酌定情节法定化责任程度

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中红外量子级联激光器的光子集成(特邀)

红外与激光工程 2022年第3期51卷 53-59页

作者：朱纯凡王贤耿汪祥王瑞军中山大学电子与信息工程学院广东广州510000

中红外光子集成芯片在环保监测、医疗诊断和国防安全等领域具有广泛的应用前景,但激光光源与无源波导光路的片上集成仍是中红外集成光学需要攻克的关键难题之一。量子级联激光器(QCL)是中红外波段的重要半导体激光光源,文中介绍了近几... 详细信息

中红外光子集成芯片在环保监测、医疗诊断和国防安全等领域具有广泛的应用前景,但激光光源与无源波导光路的片上集成仍是中红外集成光学需要攻克的关键难题之一。量子级联激光器(QCL)是中红外波段的重要半导体激光光源,文中介绍了近几年中红外QCL在光子集成方面的研究进展,包括InP基单片集成、硅基单片集成、硅基异质键合集成和Ⅲ-Ⅴ/锗混合外腔激光器。

关键词：量子级联激光器光子集成中红外硅基光子学光学传感