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Travel-Limiting Disabilities in the United States: Why Accessibility Matters?
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作者 Oluwaseun Ibukun Bhuiyan Alam 《Journal of Transportation Technologies》 2024年第3期336-357,共22页
This study evaluates the distribution of travel-limiting disabilities across genders and geographic locations in the United States. This study aims to describe and compare the socioeconomic and demographic variables o... This study evaluates the distribution of travel-limiting disabilities across genders and geographic locations in the United States. This study aims to describe and compare the socioeconomic and demographic variables of the people with and without travel-limiting disabilities across geographic locations and gender. The study further evaluates the trip purpose and impact of Covid-19 fourth wave pandemic on the use of public transit and travel to physical workplace for the people with and without travel-limiting disabilities across gender and geographic locations. The study uses the 2022 weighted National Household Travel Survey dataset and employs descriptive statistics. Results reaffirm the findings from previous literature that there are more people with travel-limiting disabilities in urban areas and among women. Over 50 percent of people aged 65 and above have a form of travel-limiting disabilities. The most trip for people with travel-limiting disabilities is made for shopping and medical purposes. Across all categories, rural areas, urban areas, male and female for the people without travel-limiting disabilities, COVID-19 fourth wave did not change the pattern of trips made to physical workplace as pre-COVID-19 era. This pattern is also observable for the people with travel-limiting disabilities in rural and urban areas. Females with travel-limiting disabilities reported making less trips to physical workplaces while male reported doing the same as before COVID-19 era. The study concludes that the quantification of travel-limiting disabilities across geographic location and gender is vital in disability study and could drive policy implementation for improved accessibility for the vulnerable population. 展开更多
关键词 national Household Travel Survey United states Travel-Limiting Disabilities Descriptive Statistics Covid-19 Disability Study
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国家建构视域下中华民族共同体认同的形塑机制--基于世界价值观调查的实证探索
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作者 李少惠 何志强 《云南民族大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第4期22-32,共11页
中华民族共同体认同的形塑,既与宏观层面国家建构中的国家—社会和中央—地方双结构休戚相关,又受微观层面地方认同、政府信任和宣传动员等要素的影响。通过对世界价值观调查(WVS)最新数据的分析,实证探索地方认同、政府信任、新闻媒介... 中华民族共同体认同的形塑,既与宏观层面国家建构中的国家—社会和中央—地方双结构休戚相关,又受微观层面地方认同、政府信任和宣传动员等要素的影响。通过对世界价值观调查(WVS)最新数据的分析,实证探索地方认同、政府信任、新闻媒介信任对中华民族共同体认同的形塑机制,研究发现:一是地方认同与中华民族共同体认同呈正向显著关系;二是政府信任在地方认同对中华民族共同体认同作用过程中,存在显著的中介作用机制;三是新闻媒介信任不仅能够调节地方认同对政府信任的影响,也调节着政府信任对中华民族共同体认同的作用机制。在国家建构视域下,为提升中华民族共同体认同,应注重“第二个结合”增强地方认同、以党建引领提升政府信任、以全过程人民民主机制赋能新闻媒介信任提升的“有形、有感、有效”的中国式路径。 展开更多
关键词 国家建构 中华民族共同体认同 地方认同 政府信任 WVS
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中华文明根性与中国特色解决民族问题正确道路的历史文化根基——基于“国家-民族”理论的理解
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作者 刘云广 张继焦 《民族学刊》 CSSCI 北大核心 2024年第1期49-59,125,共12页
以铸牢中华民族共同体意识为主线,是党的治国方略在民族工作领域的集中体现,嵌入在现代中国国家治理体系中,具有深厚的历史文化意蕴。作为对中华文明文化特征和演进逻辑的精准表述,“中华文明根性”揭示出中华文明以“秩序”追求为核心... 以铸牢中华民族共同体意识为主线,是党的治国方略在民族工作领域的集中体现,嵌入在现代中国国家治理体系中,具有深厚的历史文化意蕴。作为对中华文明文化特征和演进逻辑的精准表述,“中华文明根性”揭示出中华文明以“秩序”追求为核心的价值形态并在历史进程中形成以“统一”为取向的“一统”制度结构,这一特质为当代中国治理体系奠定了历史文化根基。在多民族国家建设方面,“中华文明根性”的规范作用体现为:本体论上“大一统”的多民族国家结构,价值论上多民族共生的中华文化,实践论上各民族一律平等的民族政治原则,目的论上共同团结奋斗共同繁荣发展的发展导向。“中华文明根性”四重维度构成了“国家—民族”的纵向关系及其所指向的“一国多族”范式。“一国多族”体现出中国特色解决民族问题正确道路的制度逻辑,决定了中国特色解决民族问题正确道路具有显著的优越性,体现为旗帜鲜明的工作指导理念、切实可行的政治参与方式、真实有效的共同体建设成就,彰显出“中国的中国观”的现代文明价值。 展开更多
关键词 “国家—民族”理论 中华文明根性 中国特色解决民族问题正确道路
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Epidemiology of shoulder dislocations presenting to United States emergency departments:An updated ten-year study
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作者 Cole M Patrick Josiah Snowden +4 位作者 Michael D Eckhoff Clare K Green John P Scanaliato John C Dunn Nata Parnes 《World Journal of Orthopedics》 2023年第9期690-697,共8页
BACKGROUND Glenohumeral dislocation is a common injury that may predispose patients to chronic pain and instability.However,there is a paucity of current data available regarding the epidemiological trends of this inj... BACKGROUND Glenohumeral dislocation is a common injury that may predispose patients to chronic pain and instability.However,there is a paucity of current data available regarding the epidemiological trends of this injury.AIM To provide an updated,comparative assessment of the epidemiology of shoulder dislocations presenting to emergency departments in the United States.We also sought to analyze patient demographic risk factors and consumer products associated with dislocation events.METHODS Data were obtained from the national electronic injury surveillance system database for glenohumeral dislocations between 2012 and 2021.Incidence,age,sex,and injury characteristics were analyzed using weighted population statistics as well as incidence rates and 95%confidence intervals(CI).RESULTS In total,an estimated 773039 shoulder dislocations(CI:640598-905481)presented to emergency rooms across the United States during the study period.The annual incidence rate was 23.96 per 100000 persons and the average patient age at the time of injury was 37.1 years.Significantly more male patients sustained dislocations than female patients(537189,69.5%,vs 235834,30.5%,P<0.001).With regard to associated consumer products,sports and recreation equipment were involved in the highest proportion of incidents(44.31%),followed by home structures and construction materials(21.22%),and home furnishings,fixtures,and accessories(21.21%).Regarding product sub-groups,stairs,ramps,landings,floors was cited in the greatest number of cases(131745).CONCLUSION The national annual incidence rate of glenohumeral dislocations throughout the study period was approximately 23.92 per 100000 persons.Male adolescents sustained the highest proportion of dislocations,with a peak incidence in age group 15-20 years,predominantly secondary to participation in sporting and recreational activities.Conversely,women experienced a relatively consistent incidence of dislocation throughout their lifespan.After age 63,the incidence rate of dislocations in females was found to surpass that observed in males. 展开更多
关键词 Shoulder dislocation EPIDEMIOLOGY United states Emergency department Glenohumeral dislocation national electronic injury surveillance system
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History and evaluation of national-scale geochemical data sets for the United States 被引量:8
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作者 David B.Smith Steven M.Smith John D.Horton 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第2期167-183,共17页
Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United States.The earliest of these,here termed the 'Shacklette' data set,was generated by a U.S. Geologica... Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United States.The earliest of these,here termed the 'Shacklette' data set,was generated by a U.S. Geological Survey(USGS) project conducted from 1961 to 1975.This project used soil collected from a depth of about 20 cm as the sampling medium at 1323 sites throughout the conterminous U.S.The National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance(NUREHSSR) Program of the U.S.Department of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in both the conterminous U.S.and Alaska.The sampled area represented about 65%of the nation.The Natural Resources Conservation Service(NRCS),from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous U.S.This data set contains analyses of more than 3000 samples.The National Geochemical Survey,a USGS project conducted from 1997 to 2009,used a subset of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the U.S.not covered by the NURE-HSSR Program.This data set contains chemical analyses for more than 70,000 samples.The USGS,in collaboration with the Mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in 2007.Sampling of three horizons or depths at more than 4800 sites in the U.S.was completed in 2010,and chemical analyses are currently ongoing.The NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the U.S.This data set currently contains data from more than 1400 sites.This paper(1) discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and(2) evaluates each data set in terms of its appropriateness as a national-scale geochemical database and its usefulness for nationalscale geochemical mapping. 展开更多
关键词 Geochemical mapping national-scale geochemical data Geochemical baselines United states
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近代国人的现代国家认同--从戊戌变法到辛亥革命 被引量:3
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作者 郑师渠 《北京师范大学学报(社会科学版)》 CSSCI 北大核心 2023年第1期115-132,共18页
近代国人的现代国家认同既是近代中国融入世界过程的应有之义,也是甲午战后新生资产阶级登上政治舞台的产物。从戊戌到辛亥,维新派与革命派两大政治派别先后领导了戊戌变法与辛亥革命,前者打破了王朝国家的坚冰,将现代国家认同的价值取... 近代国人的现代国家认同既是近代中国融入世界过程的应有之义,也是甲午战后新生资产阶级登上政治舞台的产物。从戊戌到辛亥,维新派与革命派两大政治派别先后领导了戊戌变法与辛亥革命,前者打破了王朝国家的坚冰,将现代国家认同的价值取向第一次引入了国人的视野;后者则径直推翻了王朝国家,创建了民主共和的新国家。如果说民国建立是近代国人现代国家认同的里程碑,那么其奠基则应追溯至戊戌时期。两派各有所见,各有所蔽。前者主张共和革命,顺应了时代的走向;但其倡“排满”与“种族革命”,却不免有封建种族主义的偏见,而与民族建国初衷相矛盾。后者抵拒共和,失去了曾拥有的时代弄潮儿的资格;但其反对“排满”与“种族革命”,主张以四万万人“组成一大民族”共御外侮等等,在处理中国多民族关系的问题上,表现了较前者更为理性的精神,应乎了民族建国的历史大趋势。二者的矛盾与冲突,形成了历史张力。“五族共和”显然是扬弃了双方的“所蔽”,而包容了彼此的“所见”:“大民族主义”与共和革命,即体现了民族建国的应有之义。中华民国的建立成为了近代国人实现现代国家认同的重要里程碑,同时也彰显了近代中华民族共同体意识的觉醒。 展开更多
关键词 现代国家认同 民族国家 维新派 革命派
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“博弈”视角下的美国国家公园发展理念对中国的启示--评National Parks:The American Experience 被引量:3
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作者 杨子江 谢兵 +1 位作者 向帆 吴晓东 《北京林业大学学报(社会科学版)》 2021年第2期94-100,共7页
目前,我国正处于国家公园体制稳步推进,自然保护地体系转型重构的关键时期,明确国家公园的发展思路与理念是我们亟待解决的关键问题。National Parks:The American Experience一书较为全面地探讨了美国国家公园体系的发展历程及发展理... 目前,我国正处于国家公园体制稳步推进,自然保护地体系转型重构的关键时期,明确国家公园的发展思路与理念是我们亟待解决的关键问题。National Parks:The American Experience一书较为全面地探讨了美国国家公园体系的发展历程及发展理念变迁,讲述了联邦政府、铁路公司和环保组织等利益团体围绕"国家公园该如何发展"这条主线展开的一系列博弈过程,涵盖了重要的历史事件、关键的推动性人物及相关开创性法案等内容。书中对推动美国国家公园发展的思潮和理念做了总结回顾,尤其是国家公园应该"保护什么"以及"如何保护"的思考,对完善我国国家公园体制、重构自然保护地体系具有一定的借鉴和启示意义。 展开更多
关键词 美国国家公园 多方博弈 民族主义 保护主义 扩张主义 后现代主义
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Effect of varying normal stress on stability and dynamic motion of a spring-slider system with rate- and state-dependent friction 被引量:2
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作者 Changrong He Teng-fong Wong 《Earthquake Science》 2014年第6期577-587,共11页
Incorporating rate and state friction laws, stability of linearly stable (i.e., with stiffness greater than the critical value) spring-slider systems subjected to triggering perturbations was analyzed under variable... Incorporating rate and state friction laws, stability of linearly stable (i.e., with stiffness greater than the critical value) spring-slider systems subjected to triggering perturbations was analyzed under variable normal stress condition, and comparison was made between our results and that of fixed normal stress cases revealed in previous studies. For systems associated with the slip law, the critical mag- nitude of rate steps for triggering unstable slips are found to have a similar pattern to the fixed normal stress case, and the critical velocity steps scale with a/(b - a) when k = kcr for both cases. The rate-step boundaries for the variable normal stress cases are revealed to be lower than the fixed normal stress case by 7 %-16 % for a relatively large ct = 0.56 with (b - a)/a ranging from 0.25 to 1, indicating easier triggering under the variable normal stress condition with rate steps. The difference between fixed and variable normal stress cases decreases when the α value is smaller. In the same slip- law-type systems, critical displacements to trigger instability are revealed to be little affected by the variable normal stress condition. When k 〉 kcr(V,), a spring-slider system with the slowness law is much more stable than with the slip law,suggesting that the slowness law fits experimental data better when a single state variable is adopted. In stick-slip motions, the variable normal stress case has larger stress drops than the constant normal stress case. The variable normal stress has little effect on the range of slip velocity in systems associated with the slowness law, whereas systems associated with the slip law have a slowest slip velocity immensely smaller than the fixed normal stress case, by ~ 10 orders of magnitude. 展开更多
关键词 Rate and state friction - Stability Variablenormal stress Stick-slip motion
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Non-use value assessment for wetland ecosystem service of Hongxing National Nature Reserve in northeast China 被引量:1
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作者 Xin Jin Jianzhang Ma +1 位作者 Tijiu Cai Xiaoxin Sun 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第6期1435-1442,共8页
By the contingent value method, we studied the non-use value of wetland ecosystem service of Hongxing National Nature Reserve (HNNR) in Heilongjiang Pro- vince, northeast China. The proportion of respondents willing... By the contingent value method, we studied the non-use value of wetland ecosystem service of Hongxing National Nature Reserve (HNNR) in Heilongjiang Pro- vince, northeast China. The proportion of respondents willing to pay (WTP) for protection of HNNR was 63 %. The WTP ratio was affected by geographical area, contact nature, personal preferences, and familiar degree of the respondents. The WTP value was affected by age, education level and career of the respondents. The mainly reasons for people rejecting to pay for protecting HNNR were "I am not familiar to HNNR" and "I had no capacity for additional spending because of low income". Weighted average individual WTP value was CNY 59.26 Yuan ind.^-1 year^-1 for all the respondents with WTP. The total non-use ecosystem service value of HNNR was CNY 1430 million Yuan in 2013. The heritage value was highest followed by existence value and option value. From the high ecosystem service value in HNNR, it is very important to construct nature reserve for protecting natural ecosystems and human sustainable use of natural resources. 展开更多
关键词 Ecosystem service Non-use value Hongxing national Nature Reserve - Xiaoxing'an Mountains
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A New Cadmium(Ⅱ) Coordination Polymer Extended through Hydrogen Bonds and π-π Stacking Interactions: Synthesis and Photoluminescence Property 被引量:1
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作者 肖国斌 方子涵 姚小强 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第12期1987-1993,1846,共8页
A new coordination polymer, {[Cd(OPY)(tdc)(HO)]·H2 O}n(OPY = 4,4?-(oxybis(4,1-phenylene))dipyridine, H2 tdc = thiophene-2,5-dicarboxylic acid), has been synthesized hydrothermally based on a V-shaped ligand OPY. ... A new coordination polymer, {[Cd(OPY)(tdc)(HO)]·H2 O}n(OPY = 4,4?-(oxybis(4,1-phenylene))dipyridine, H2 tdc = thiophene-2,5-dicarboxylic acid), has been synthesized hydrothermally based on a V-shaped ligand OPY. The structure was fully characterized by elemental analysis, FT-IR spectroscopy, and X-ray single-crystal diffraction analysis. In1, two OPY ligands and one water molecule acted as terminal ligands coordinating to Cdcation to form [Cd(OPY)HO]units, which are then linked by tdc2-ligands to generate a one-dimensional chain. Every two adjacent chains linked by extensive O–H···O hydrogen bonds constitute one-dimensional double-chains, and such chains are extended into two-dimensional layers via O–H···N hydrogen bonds. These layers are further connected to form a three-dimensional supramolecular architecture via π-π stacking interactions. In addition, the thermal stability and solid state fluorescence property of 1 were also investigated. 展开更多
关键词 crystal structure hydrogen bond π-π stacking interaction solid state fluorescence property
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Solid-state synthesis of Sr-and Co-doped LaMnO_3 perovskites 被引量:1
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作者 马文会 谢刚 +1 位作者 陈书荣 崔衡 《中国有色金属学会会刊:英文版》 CSCD 2001年第6期904-907,共4页
The synthesis process for La 1- x Sr x Mn 1- y Co y O 3- δ ( x = 0.2, 0.3; y = 0.2, 0.8, designated as LSMC below) perovskite oxides prepared by solid state reaction was investigated using DSC/TG, XRD, EPMA and parti... The synthesis process for La 1- x Sr x Mn 1- y Co y O 3- δ ( x = 0.2, 0.3; y = 0.2, 0.8, designated as LSMC below) perovskite oxides prepared by solid state reaction was investigated using DSC/TG, XRD, EPMA and particle size analysis methods. It was found that LSMCs were all of single phase and the synthesis process might be divided into three stages: the decomposition of reactants, the formation of LaMn(Co)O 3 based oxides, and the formation of LSMC solid solution. Typical average and the peak value of particle size, and the specific surface area are 14.65?μm, 16.4?μm and 1.38?m 2/mL, respectively, for mixed reactants and are 23.81?μm, 32.11?μm and 0.5?m 2/mL, respectively, for powder synthesized at 1?200?℃ for 8?h in air. 展开更多
关键词 solid state reaction synthesis La 1- x Sr x Mn 1- y Co y O 3- δ perovskite intermediate temperature SOFCs
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Intestinal parasites infection and associated factors among school children in Dagi primary school, Amhara National Regional State, Ethiopia
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作者 Mulat Alamir Worku Awoke Amsalu Feleke 《Health》 2013年第10期1697-1701,共5页
Introduction: Intestinal parasitic infections are among the most common communicable diseases worldwide, particularly in developing countries. Worldwide, about 3.5 billion people are affected, and 450 million are ill ... Introduction: Intestinal parasitic infections are among the most common communicable diseases worldwide, particularly in developing countries. Worldwide, about 3.5 billion people are affected, and 450 million are ill as a result of these infections, among whom, the majority are children. The objective of this study was to assess prevalence of intestinal parasites infection and associated risk factors among school children in Dagi primary school, ANRS, Ethiopia. Methods: Institutional-based cross-sectional study was conducted by involving 399 school children from 24 September to 19 October, 2012. Structured questionnaires were used to identify environmental, socio-demographic and behavioral factors and stool specimens were collected and examined for parasites using direct smear and formal-ether concentration technique. Data analysis was done by using SPSS version 15 statistical soft ware. Results: Eight species of intestinal parasites were identified with an overall prevalence of 77.9%. Students were infected with one or more intestinal parasites and the predominant parasite was hook worm, 94 (23.6%) followed by G. lamblia 91 (22.8%), E. histoltica 86 (21.6%) and Strongyloides 6 (1.5%). The presence of mixed parasitic infection was 106 (34.1%), double and triple infections were 97 (91.5%) and 9 (8.5%) respectively. Intestinal parasitic infection was higher in children whose fathers’ occupational status were farmers, who had unclean finger nails and who did not have the habit of wearing shoes (p parasites infection was an important public health problem among Dagi primary school children. Therefore, the local health office and other governmental and non-governmental organizations need to give attention to this serious problem of intestinal parasitic infection of school children. 展开更多
关键词 Intestinal PARASITIC INFECTIONS Amhara nationAL REGIONAL state Ethiopia
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联合国维持和平行动与后殖民国家建构(1980-2015年) 被引量:2
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作者 卢凌宇 王潇茹 《国际安全研究》 CSSCI 北大核心 2023年第1期99-128,159,160,共32页
联合国是维和行动主要的组织者和实施者。冷战结束以来,西方主导的联合国维和的目标由维护和平逐渐转变为战后重建,并开始承担复杂的国家建构任务。一方面,维和给目标国带来了和平,维和人员的日常开支对目标国经济的恢复和发展作出了一... 联合国是维和行动主要的组织者和实施者。冷战结束以来,西方主导的联合国维和的目标由维护和平逐渐转变为战后重建,并开始承担复杂的国家建构任务。一方面,维和给目标国带来了和平,维和人员的日常开支对目标国经济的恢复和发展作出了一定贡献。但是维和任务的速成性和维和经济造成的收入两极分化等因素,都对目标国的经济发展产生了消极影响。另一方面,维和人员的税收豁免权、维和人员与其他社会群体的收入差距以及由此导致的政府部门人才流失和腐败、平行行政部门的出现等都严重削弱了政府对社会的渗透和控制能力。不仅如此,维和人员税收豁免和收入两极分化显著地降低了民众的纳税意愿,使得逃税和抗税盛行,提高了征税难度。维和部队对于目标国政府军向民众单方面使用暴力采取的不干涉态度,也强化了社会抗税心理。所以,西方主导的联合国维和行动既缩小了目标国的税基,降低了官僚机构的效能,又打击了民众的纳税意愿,显著地降低了目标国的财政汲取能力。本文对1980—2015年126个后殖民国家的大样本统计分析表明,无论是短期还是长期,西方主导的联合国维和行动和后殖民目标国的汲取能力都呈显著的负相关关系。 展开更多
关键词 联合国维和行动 后殖民国家 国家建构 国家能力 汲取能力
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Elaborately tuning the electronic structure of single-atom nickel sites using nickel nanoparticles to markedly enhance the electrochemical reduction of nitrate into ammonia 被引量:1
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作者 Zichao Xi Jiaqian Wang +4 位作者 Baocang Liu Xuan Xu Peng Jing Rui Gao Jun Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期32-42,I0003,共12页
The electrochemical reduction of nitrate to ammonia(NH3) can be used to recycle nitrogen and offers a decarbonized route for sustainable NH3production,but requires efficient electrocatalysts.Herein,we have rationally ... The electrochemical reduction of nitrate to ammonia(NH3) can be used to recycle nitrogen and offers a decarbonized route for sustainable NH3production,but requires efficient electrocatalysts.Herein,we have rationally designed and fabricated a novel self-supported electrocatalyst comprised of Ni nanoparticles(NiNPs) embedded in Ni single atoms(NiSAs) anchored to nitrogen-doped carbon nanotubes grown on carbon cloth(NiNPs@NiSAs-NCNTs/CC) used for an efficient nitrate reduction reaction(NO3-RR) to produce NH_(3).The electrocatalyst can attain a maximum NH3yield rate of 27.67±1.16 mgNH3h^(-1)cm^(-2)at-1.4 V vs.reversible hydrogen electrode(RHE) and nearly 100% Faradic efficiency in the range of-1.2--1.4 V vs.RHE in a neutral medium,outperforming the previously reported Ni-based catalysts.Our experimental analysis and theoretical calculations have demonstrated that the moderate electrondeficient state of NiSAsregulated by NiNPsnot only facilitates the enrichment of NO_(3)^(-),but also benefits the formation of NO3*and decrease in the energy barrier of the rate-limiting step,thus resulting in the enhanced NO3-RR performance. 展开更多
关键词 Nitratereductionreaction Moderateelectron-deficient state Self-supported ELECTROCATALYST Enrichmentof NO_(3)^(-) Theoreticalcalculations
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Modeling of Solid-state Polycondensation of Poly (ethylene terephthalate)
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作者 邓德纯 王燕萍 +2 位作者 蒋歧康 唐志廉 黄南薰 《Journal of China Textile University(English Edition)》 EI CAS 2000年第4期30-33,共4页
A mathematical model has been developed to handle the reactions in Poly(ethylene terephthalate) (PET) undergoing polycondensation reactions in the solid state. The effect of temperature on chain mobility was considere... A mathematical model has been developed to handle the reactions in Poly(ethylene terephthalate) (PET) undergoing polycondensation reactions in the solid state. The effect of temperature on chain mobility was considered to estimate the rate constants of chemical reactions. The polymer crystalline fraction is modeled as containing only repeat units, thus concentrating end groups and conden-sates in the amorphous fraction. This model is compared with PET reaction data with good results. 展开更多
关键词 SOLID - state POLYMERIZATION PET POLYMER REACTION engineering.
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Equation of State of Nuclear Matter in Chiral σ-ω Model
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作者 CHENWei DONGDong-Qiao +2 位作者 WENDe-Hua LIUGuo-Tao LIULiang-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第6期925-928,共4页
The equation of state of nuclear matter is studied in the 1-loop approximation of chiral linear σ-ω model.By introducing the density-dependent coupling constants, the problem of tachyon pole in the chiral σ-ω mode... The equation of state of nuclear matter is studied in the 1-loop approximation of chiral linear σ-ω model.By introducing the density-dependent coupling constants, the problem of tachyon pole in the chiral σ-ω model is resolved.The 1-loop contributions ofσ and π mesons to the nucleon's binding energy are included, while the empirical properties of nuclear matter such as saturation density, binding energy, and incompressibility are well reproduced. 展开更多
关键词 equation of state chiral σ-ω model
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Materials Design on the Origin of Gap States in a High-κ/GaAs Interface
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作者 Weichao Wang Cheng Gong +3 位作者 Ka Xiong Santosh K.C. Robert M.Wallace Kyeongjae Cho 《Engineering》 SCIE EI 2015年第3期372-377,共6页
Given the demand for constantly scaling micro- electronic devices to ever smaller dimensions, a SiO2 gate dielectric was substituted with a higher dielectric-constant material, Hf(Zr)O2, in order to minimize current... Given the demand for constantly scaling micro- electronic devices to ever smaller dimensions, a SiO2 gate dielectric was substituted with a higher dielectric-constant material, Hf(Zr)O2, in order to minimize current leakage through dielectric thin film. However, upon interfacing with high dielectric constant (high-κ) dielectrics, the electron mobility in the conventional Si channel degrades due to Coulomb scattering, surface-roughness scattering, remotephonon scattering, and dielectric-charge trapping.Ⅲ-Ⅴ and Ge are two promising candidates with superior mobility over Si. Nevertheless, Hf(Zr)O2/Ⅲ-Ⅴ(Ge) has much more complicated interface bonding than Si-based interfaces. Successful fabrication of a high-quality device critically depends on understanding and engineering the bonding configurations at Hf(Zr)O2/Ⅲ-Ⅴ(Ge) interfaces for the optimal design of device interfaces. Thus, an accurate atomic insight into the interface bonding and mechanism of interface gap states formation becomes essential. Here, we utilize first- principle calculations to investigate the interface between HfO2 and GaAs. Our study shows that As--As dimer bonding, Ga partial oxidation (between 3+ and 1+) and Ga- dangling bonds constitute the major contributions to gap states. These findings provide insightful guidance for optimum interface passivation. 展开更多
关键词 high-mobility device high-κ/Ⅲ- interface interfacial gap states first-principle calculations
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“全民一体”:一个述说中华民族的原创概念 被引量:2
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作者 周平 《理论月刊》 CSSCI 北大核心 2024年第4期5-12,共8页
民族复兴被确立为国家发展目标,中华民族得到了前所未有的凸显,也进一步突出了中华民族与国家之间的内在联系。为了体现中华民族的国家属性,形成对中华民族的完整述说,笔者在中华民族“多元一体”概念的基础上,提出了中华民族“全民一... 民族复兴被确立为国家发展目标,中华民族得到了前所未有的凸显,也进一步突出了中华民族与国家之间的内在联系。为了体现中华民族的国家属性,形成对中华民族的完整述说,笔者在中华民族“多元一体”概念的基础上,提出了中华民族“全民一体”概念,并通过原创的“人口国民化”“国民整体化”等概念来丰富其内涵。因此,就能将从中华民族与现代国家关系角度提出的“全民一体”概念,与从国内民族关系角度提出的“多元一体”概念结合起来,在既揭示中华民族与世界上其他现代民族的共同性,又揭示中华民族特殊性的基础上,对中华民族进行完整、有效的述说。 展开更多
关键词 中华民族 民族国家 全民一体 多元一体 人口国民化 国民整体化
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Setting up State Holding Corporations——an Interview with He Boquan, Vice President of the China National Nonferrous Industry Corporation
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《China's Foreign Trade》 1995年第6期13-14,共2页
An announcement was made on November 4, 1994, on making the China National Nonferrous Industry Corporation one of the three State holding corporations for experiment at a national conference on experimenting on modern... An announcement was made on November 4, 1994, on making the China National Nonferrous Industry Corporation one of the three State holding corporations for experiment at a national conference on experimenting on modern enterprises sponsored by the State Council. The appearance of State holding corporations is the result of China’s deepening economic restructuring and an important and integral part of deepening enterprise reform. 展开更多
关键词 Vice President of the China national Nonferrous Industry Corporation Setting up state Holding Corporations an Interview with He Boquan
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The “Non-Locality” of Entangled States Is Seeming Phenomenon
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作者 Marat Guryev 《Journal of Applied Mathematics and Physics》 2017年第9期1791-1796,共6页
EPR raised fundamental problems of non-locality (NL) in the case of entangled states (ES) 82 years ago. These problems were not solved until now. EPR and their followers used and would continue to use calculation meth... EPR raised fundamental problems of non-locality (NL) in the case of entangled states (ES) 82 years ago. These problems were not solved until now. EPR and their followers used and would continue to use calculation methods that were available at that time. However, we can easily explain this observable NL as a trivial result of conservation laws (CL) within modern quantum mechanics (MQM). But application of CL requires materialistic descriptions of reality in a micro world in contrast to so-called quantum measurement theory (QMT), which was created mainly in the times of EPR and is widely accepted until now. We have to use a materialistic description, just as many physicists who actually work with high precision do by default. In this article, practical examples are given for real, precise measurements of wave functions of molecules and crystals, which, of course, were not known to EPR and were not noticed by their followers. We should acknowledge that QMT is merely an unneeded complication of simple relations of MQM. NL is the seeming result of these complications. 展开更多
关键词 NON-LOCALITY ENTANGLED states Quantum MEASUREMENT Theory EPR Electron DIFFRACTION Neutron DIFFRACTION y - RAY DIFFRACTION MEASUREMENT of Wave Function
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