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Effect of Carbon on DA718 Alloy with P Addition

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Journal of Materials Science & Technology 2003年第6期19卷 616-618页

作者： Na LI, Shouren GUO, dezhong LU, Wenru SUN, Yan XU and Zhuangqi HUInstitute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

Lower content of carbon can further improve the stress rupture life of p-modified DA 718 alloy up to more than 270%. Meanwhile, the ductility of the alloy decreased a little. More boron atoms dissociate due to decreasing carbon content and interact with phosphorus which brings the longer stress rupture life of the alloy. Less carbon may induce more phosphorus segregating in the grain boundary and result in brittleness.

关键词： DA 718 alloy Carbon Phosphorus

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全球高科技产品贸易结构演化及影响因素

地理学报 2020年第12期75卷 2759-2776页

作者：段德忠杜德斌华东师范大学全球创新与发展研究院上海200062 华东师范大学城市与区域科学学院上海200241

为清晰刻画全球高科技产品贸易体系变迁,本文利用世界银行以及联合国商品贸易数据库中2000-2017年高科技产品贸易数据,从产品结构、网络结构和影响因素3个方面探讨了全球高科技产品贸易结构的演化态势。研究发现:①产品结构上,以电信设... 详细信息

为清晰刻画全球高科技产品贸易体系变迁,本文利用世界银行以及联合国商品贸易数据库中2000-2017年高科技产品贸易数据,从产品结构、网络结构和影响因素3个方面探讨了全球高科技产品贸易结构的演化态势。研究发现:①产品结构上,以电信设备为主的电子通讯产品主导全球高科技贸易发展,但在国家尺度上,化学产品和武器产品是大部分国家(地区)的进口依赖产品或出口优势产品;②拓扑结构上,全球高科技产品贸易网络持续扩张,联系紧密,是一典型的"小世界"网络,并发育出稳定的"核心—边缘"式的等级层次结构;③空间结构上,全球高科技产品贸易格局呈现出由欧洲—北美主导向由东亚主导转变,贸易最大国也由美国转变为中国,网络空间结构也呈现出由以美国为核心的"双拱"格局向以中国为核心的"多拱"格局转变,但美国依然在多种高科技产品贸易网络中占据核心地位;④影响因素上,贸易规模、经济邻近性和文化邻近性对全球高科技产品贸易网络演化皆具有一定的正向作用,地理距离对全球高科技产品贸易网络的演化起到明显的负向作用。

关键词：高科技贸易产品结构拓扑结构空间结构影响因素

Twenty-five years of progress in geopolitics research： Efforts from China＇s geographers

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Journal of Geographical Sciences 2016年第8期26卷 1223-1242页

作者： DU Debin DUAN dezhong LIU Chengliang MA Yahua School of Urban and Regional Science East China Normal University Shanghai 200062 China Institute for Innovation and Strategic Studies East China Normal University Shanghai 20062 China School of Business Shanghai Normal University Shanghai 200235 China

The world is currently undergoing profound changes, with a shift in global power centers and reordering of international power spaces, assigning new theoretical tasks as well as providing new opportunities for geopolitics research in China. Despite the peripheral nature of geopolitics research within their discipline, geographers have played a fundamental role in its origins and revival, from classical geopolitics（i.e., the German school of geopolitics and the Anglo-American school of geo-strategy）, to internal geopolitics（i.e., electoral geography and administrative geography）, to the new geopolitics（i.e., formal geopolitics）, and to recent critical geopolitics（i.e., popular geopolitics）. Although only few of these researchers were from China, great strides have been made in geopolitics and political geography research in China, with useful results being obtained. After demonstrating the importance of geopolitics research for the rising China, this review provides an overview of geopolitics papers led by China＇s geographers in the past few decades, describing their achievements, the problems they have faced, and the directions they have taken. Twenty-five years of geopolitics have produced a range of accomplishments, with a growth in the quality and size of research groups and institutions, an expanding literature, and some geo-strategic breakthroughs. Obviously, geographers have successfully reclaimed geopolitics, but some crucial topics are still absent or weak in the geopolitical research agenda, and need to be pursued vigorously. Most of the attention, from a positivistic perspective, has been paid to reflecting Western geopolitical thoughts, describing patterns of international power relations, and offering foreign policy advice（in a problem-focused orientation）, rather than determining mechanisms and performing theoretical analyses（in a theoretical orientation）, resulting in a lack of independent value judgments and of a theoretical basis for the subject. Mor

关键词： geopolitics geo-strategy world geography China research progress

Uncovering the solid-phase conversion mechanism via a new range of organosulfur polymer composite cathodes for lithium-sulfur batteries

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Journal of Energy Chemistry 2023年第9期84卷 459-466页

作者： Xiang Li dezhong Liu Ziyi Cao Yaqi Liao Zexiao Cheng Jie Chen Kai Yuan Xing Lin Zhen Li Yunhui Huang Lixia Yuan State Key Laboratory of Material Processing and Die&Mold Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina

The sulfur cathodes operating via solid phase conversion of sulfur have natural advantages in suppressing polysulfide dissolution and lowering the electrolyte dosage,and thus realizing significant improvements in both cycle life and energy *** realize an ideal solid-phase conversion of sulfur,a deep understanding of the regulation path of reaction mechanism and a corresponding intentional material and/or cathode design are highly ***,via covalently fixing of sulfur onto the triallyl isocyanurate,a series of S-triallyl isocyanurate organosulfur polymer composites(STIs) are *** between the structure and the electrochemical conversion behavior of STIs is systematically *** is found that the structure of STIs varies with the synthetic temperature,and correspondingly the electrochemical redox of sulfur can be controlled from conventional "solid-liquid-solid" conversion to the "solid-solid" *** the STI series,the STI-5 composite realizes an ideal solid-phase conversion and demonstrates great potential for building a Li-S battery with high-energy density and long-cyclelife:it realizes stable cycling over 1000 cycles in carbonate electrolyte,with a degradation rate of0.053% per cycle;the corresponding pouch cell shows almost no capacity decay for 125 cycles under the conditions of high sulfur loading(4.5 mg cm^(-2)) and lean electrolyte(8 μL mg_s^(-1)).In addition,the tailoring strategy of STI can also apply to other precursors with allyl functional groups to develop new organosulfur polymers for "solid-solid" sulfur *** vulcanized triallyl phosphate(STP) and triallylamine(STA) both show great lithium storage *** strategy successfully develops a new family of organosulfur polymers as cathodes for Li-S batteries via solid-phase conversion of sulfur,and brings insights to the mechanism study in Li-S batteries.

关键词： Organosulfur polymer Lithium–sulfur batteries Allyl functional groups Reaction mechanism Solid–solid conversion

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中国城市绿色技术扩散的时空过程与形成机制

地理学报 2023年第8期78卷 2001-2018页

作者：段德忠金红华东师范大学全球创新与发展研究院上海200062

以绿色专利转让刻画绿色技术扩散,分析了2001—2020年中国城市绿色技术扩散的时续动态以及空间格局,揭示了中国城市绿色技术扩散活动中的热门技术、行为主体和城市类型,并探讨了驱动中国城际绿色技术扩散的主要因素。研究发现:(1)中国... 详细信息

以绿色专利转让刻画绿色技术扩散,分析了2001—2020年中国城市绿色技术扩散的时续动态以及空间格局,揭示了中国城市绿色技术扩散活动中的热门技术、行为主体和城市类型,并探讨了驱动中国城际绿色技术扩散的主要因素。研究发现:(1)中国绿色技术交易市场中的热门技术由环境治理技术快速转变为绿色建筑技术和清洁能源技术,企业始终是绿色技术扩散的主要行为体;(2)绿色技术跨城流动成为新常态,城市角色逐渐由自给自足式的城内集散型向开放创新式的城际集散型发展,全国统一的绿色技术交易大市场正在逐渐形成;(3)绿色技术扩散活动高度集聚在由东部沿海和长江经济带组成的“T”型地区,其中城际绿色技术扩散形成以京津、长三角、珠三角、成渝地区为枢纽的菱形网络;(4)遵循偏好连接和同配性法则,城际绿色技术扩散网络中新加入城市倾向于从枢纽城市获取绿色技术,但枢纽城市间的绿色技术流动更加频繁;(5)多维邻近性分析框架下的模型回归结果揭示了城市间技术差距、地理邻近性、经济邻近性、认知邻近性对城际绿色技术扩散的形成机制差异。

关键词：绿色专利绿色技术扩散时空格局城市类型驱动因素中国

An investigation into the occupational protection status of clinical nursing staff exposed to anti-tumor drugs

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Journal of Medical Colleges of PLA(China) 2012年第2期27卷 113-119页

作者： Yuan Yanqin Xu dezhong Department of Burn ＆ Plastic Surgery Tangdu Hospital Fourth Military Medical University Xi ＂an 710038 China Department of Epidemiology Fourth Military Medical University Xi ＇an 710032 China

Objective:To investigate the occupational protection status of clinical nursing staff vocationally exposed to anti-tumor ***:A self-designed questionnaire was used to survey 180 clinical nursing staff vocationally exposed to anti-tumor ***:Recognition of the need for protection and dependent occupational protection behaviors were very poor in clinical nursing staff vocationally exposed to anti-tumor *** management of the occupational protection of clinical nursing staff vocationally exposed to anti-tumor drugs was also seriously ***:There is deficiency in the understanding and related protection practices of clinical nursing staff vocationally exposed to anti-tumor drugs in our *** protection measures currently employed in medical practice are inadequate in virtually every aspect *** is recommended that all clinical nursing staff should receive full occupational protection training in these *** training must raise nursing staff's awareness of the need for occupational protection and standardize their occupational protection behaviors to conform to "best practice" *** "best practice" models should be quickly established and all staff made cognizant of them *** addition,where occupational protection systems are already in place,they should be improved to come into line with the new "best practice" models instigated.

关键词： Nursing staff Anti-tumor drug Occupational protection

Highly branched poly(β-amino ester)s with narrow molecular weight distribution: Fractionation and gene transfection activity

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Chinese Chemical Letters 2023年第3期34卷 383-387页

作者： Chenfei Wang Litao Sun Qiuxia Li Zhili Li Chengyuan Xu Xinyue Zhang Jianjun Shi Hao Zhou Wenxin Wang dezhong Zhou School of Chemical Engineering and Technology Xi’an Jiaotong UniversityXi’an 710049China Key Laboratory of Water Pollution Treatment&Resource Reuse Hainan Normal UniversityHaikou 571158China State Key Laboratory of Medicinal Chemical Biology Tianjin Key Laboratory of Protein Scienceand College of Life SciencesNankai UniversityTianjin 300071China Department of Dermatology The Second Hospital Affiliated to Xi’an Jiaotong UniversityXi’an 710061China Charles Institute of Dermatology School of MedicineUniversity College DublinDublin 4Ireland

Highly branched poly(β-amino ester)s(HPAEs) have shown their great promise in gene delivery. However, their broad molecular weight distribution(MWD) poses an additional challenge to the mechanistic understanding of the influence of molecular weight(MW) on their gene transfection activity. Using a stepwise precipitation strategy, HPAEs were fractionated. It is shown that MW has a significant effect on the transfection activity and cytotoxicity of HPAEs. The intermediate MW mediates higher transfection efficiency while maintaining high cell viability. Mechanistic studies show that the intermediate MW confers stronger DNA binding affinity to HPAEs, leading to the formulation of polyplexes with a relatively smaller size and more positive zeta potential. This study not only suggests a simple strategy to fractionate HPAEs with narrow MWD but also provides new insights into understanding the structure-property relationship, which would facilitate the clinical translation of HPAEs in gene therapy.

关键词： Gene transfection Non-viral vector Highly branched poly(β-amino ester)s Fractionation Transfection activity

Implications of stalagmite density for past climate change:An example from stalagmite growth during the last deglaciation from Wanxiang Cave,western Loess Plateau

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Chinese Science Bulletin 2010年第34期55卷 3936-3943页

作者： ZHANG dezhong ZHANG PingZhong SANG WenCui CHENG Hai WU XiuPing YUAN Ye BAI YiJun WANG JiangLin JIA JiHong Key Laboratory of Western China's Environmental System of Ministry of Education College of Earth and Environmental Sciences Lanzhou University Lanzhou 730000 China Institute of Global Environmental Change Xi'an Jiaotong University Xi'an 710049 China Department of Geology and Geophysics University of Minnesota Minneapolis MN 55455 USA

The density of a stalagmite(WX42A)from Wanxiang Cave,Wudu County,Gansu Province,China,in the western margin of the Asian summer monsoon region,presents regular fluctuations in different deposition periods during the last *** long timescales,high-precision 230Th dating and high-resolution stalagmite density data indicate that the density-time series between 17644 a BP and 12758 a BP is quite similar to the stalagmite δ18O record which reflects Asian monsoon ***/weakening(lighter/heavier stalagmite δ18O values)of the Asian monsoon is accompanied by increase/decrease in stalagmite *** short timescales,decrease in stalagmite density correlates to monsoon-retreat events such as the Inter-AllerФd Cold Period(IACP),Older Dryas(OD)and Inter-BФlling Cold Period(IBCP).Generally,this kind of decrease in stalagmite density reflects precipitation decrease with weakening of the Asian monsoon,which in turn slows cave dripwater rate and decreases crystal nuclei,leading to enlargement of calcite crystals,weakened biological activity and decreased soil pCO2 which increases the abundance of impure detrital materials in ***,during the period of large amplitude reduction of precipitation and biological activity which resulted from extreme monsoon-retreat events,temperature variation would dominate fluctuation of stalagmite *** example,stalagmite density increased suddenly when temperature dropped suddenly in the north Atlantic during Heinrich event 1(H-1).This may be caused by low seepage water temperature,more dissolved calcium carbonate,compact regular crystals forming under higher supersaturation,leading to the stalagmite increased *** density fluctuation sensitively recorded stalagmite growth history and environment,demonstrating that stalagmite density can be used as a proxy for paleoclimatic research.

关键词：石笋记录记录密度黄土高原西部末次冰消期 Heinrich事件气候变化笋生长方解石晶体

陶瓷基复合材料的研究现状及在发动机上的应用展望

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农业机械学报 2006年第11期37卷 171-176页

作者：黄德中绍兴文理学院机电工程系

在陶瓷材料的基础上采用各种增韧手段和改变材料结构制备的陶瓷基复合材料,具有耐磨、耐高温和耐侵蚀性能,是满足机械性能要求的发动机热端零件的理想材料。本文论述了陶瓷基复合材料的性能、制备方法,讨论了陶瓷基复合材料在发动机上... 详细信息

在陶瓷材料的基础上采用各种增韧手段和改变材料结构制备的陶瓷基复合材料,具有耐磨、耐高温和耐侵蚀性能,是满足机械性能要求的发动机热端零件的理想材料。本文论述了陶瓷基复合材料的性能、制备方法,讨论了陶瓷基复合材料在发动机上的应用前景及评价。

关键词：陶瓷基复合材料发动机综述