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Does the Dzungarian racerunner(Eremias dzungarica Orlova,Poyarkov,Chirikova,Nazarov,Munkhbaatar,Munkhbayar&Terbish,2017)occur in China?Species delimitation and identification with DNA barcoding and morphometric analyses

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Zoological Research 2021年第3期42卷 287-293页

作者： Jin-Long Liu Tatjana N.Dujsebayeva Marina A.Chirikova Xiong Gong Da-Jiang Li xian-guang guo Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041China Institute of Zoology of Republic of Kazakhstan Almaty 050060Kazakhstan

The Eremias multiocellata-przewalskii species complex is a viviparous group in the genus Eremias,and a well-known representative of taxonomically complicated *** this complex,a new ***(Orlova et al.,2017)-has been described recently from western Mongolia and eastern Kazakhstan,with an apparent distribution gap in northwestern *** this study,we used an integrative taxonomic framework to address whether *** indeed occurs in *** specimens previously classified as *** were collected in eastern Kazakhstan and the adjacent Altay region in *** cytochrome c oxidase I(COI)barcodes were sequenced and compiled with those from Orlova et al.(2017)and analyzed with the standard and diverse barcoding techniques.

关键词： China. eastern northwestern

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基于振动的钛合金膜盘材料疲劳性能试验研究

实验力学 2018年第2期33卷 239-244页

作者：许巍杨宪峰郭广平北京航空材料研究院材料检测与评价航空科技重点实验室航空材料检测与评价北京市重点实验室先进高温结构材料国防科技重点实验室

介绍了一种钛合金膜盘材料疲劳性能的试验研究，建立了闭环控制下的振动疲劳试验系统，完成了对该膜盘10°角切片试样在振动条件下的疲劳试验，给出了该试样的疲劳应力一寿命曲线以及疲劳极限值，最后分析了切片试样振动疲劳的主要失效... 详细信息

介绍了一种钛合金膜盘材料疲劳性能的试验研究，建立了闭环控制下的振动疲劳试验系统，完成了对该膜盘10°角切片试样在振动条件下的疲劳试验，给出了该试样的疲劳应力一寿命曲线以及疲劳极限值，最后分析了切片试样振动疲劳的主要失效模式。结果表明：本试验方法高效可靠，时间和材料成本低，所得振动疲劳性能参数与旋转弯曲疲劳性能参数接近，而断口表现出典型的单侧起源的疲劳扩展特征。

关键词：膜盘线性振动振动疲劳测试失效模式

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高纯度的棉铃虫性信息素主要组份的合成

化学学报 1985年第4期43卷 400-402页

作者：刘玲玉林国强王咸庆郭广忠中国科学院上海有机化学研究所

棉铃虫(Heliothis amigora)是世界性棉花害虫,在我国产棉区的危害也甚为严重.棉铃虫性信息素主要组份为顺-9-十六碳烯醛-1(1)和顺-11-十六碳烯醛-1(2)等烯醛类化合物.1和2的合成报道是以Wittig反应为主或炔锂和卤代烷缩合,这种合成路线... 详细信息

棉铃虫(Heliothis amigora)是世界性棉花害虫,在我国产棉区的危害也甚为严重.棉铃虫性信息素主要组份为顺-9-十六碳烯醛-1(1)和顺-11-十六碳烯醛-1(2)等烯醛类化合物.1和2的合成报道是以Wittig反应为主或炔锂和卤代烷缩合,这种合成路线所得的1和2.其顺式双键的纯度均仅95~98%,总产率约35%.因为昆虫对信息素的几何异构体组成非常敏感.所以几何异构体的纯度在合成昆虫信息素中特别重要.为此我们选择了用顺-二(烯基)铜锂的烷基化反应合成1和2(图式1A).得到了>99.5%顺式构型的产物.用此法不仅合成步骤短,而且总产率高达80%.此外用本法还可通过变换图式1中的m或n数得到一系列双键位置不同的长链脂肪醛、醇及其乙酸酯的昆虫性信息素化合物.溴化物3和锂反应生成的锂试剂与碘化亚铜,乙炔及碘代烷通过一步反应即生成顺式烯化合物4,产率90%.然后除去4的保护基团和再经PCO氧化,得1和2,总产率分别为79.5%

关键词：六碳烯顺式双键碳炔组份棉铃虫棉铃实夜蛾棉花害虫性信息素性外激素

双色场Jaynes-Cummings模型的量子理论

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物理学报 1988年第12期 1956-1964页

作者：罗耕贤郭光灿中国科学技术大学物理系

本文采用全量子理论精确地导出失谐对称的双色Jaynes-Cummings模型的解,并通过数值方法讨论了两个初始光场具有相同与不同统计特性时,原子系统的动力学行为,结果发现了新的衰变-复苏(couapse-revival)现象,详细地研究了影响这个现象的... 详细信息

本文采用全量子理论精确地导出失谐对称的双色Jaynes-Cummings模型的解,并通过数值方法讨论了两个初始光场具有相同与不同统计特性时,原子系统的动力学行为,结果发现了新的衰变-复苏(couapse-revival)现象,详细地研究了影响这个现象的各种因素。

关键词：光场统计性质辐射场量子光学双色场 Jaynes-Cummings 失谐量量子理论

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抗昆虫保幼激素类似物的合成

化学学报 1980年第5期 451-458页

作者：甘立宪郭广忠徐锦文中国科学院上海有机化学研究所

为寻找有抗保幼激素活性的早熟素类似物,我们合成了几个新的、结构与早熟素相似的氧杂萘衍生物供生物试验筛选。在多聚磷酸存在下,使焦棓酚-1-甲醚(4)与过量的β,β-二甲基丙烯酸(5)缩合生成相应的色满酮(6),然后经锂铝氢还原及盐酸催... 详细信息

为寻找有抗保幼激素活性的早熟素类似物,我们合成了几个新的、结构与早熟素相似的氧杂萘衍生物供生物试验筛选。在多聚磷酸存在下,使焦棓酚-1-甲醚(4)与过量的β,β-二甲基丙烯酸(5)缩合生成相应的色满酮(6),然后经锂铝氢还原及盐酸催化脱水,即得所需产物8.8分别再与硫酸二甲酯,丙炔溴及异氰酸甲酯反应便可得类似物10、11和12。化合物8、10、11、12的生物活性试验正在进行中。

关键词：早熟素抗保幼激素类似物石油醚重结晶同型物溶剂油再结晶(冶金) OCH ABX

Design strategies of Pd-based electrocatalysts for efficient oxygen reduction

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Rare Metals 2023年第6期42卷 1778-1799页

作者： Chun-Jie Li guang-Cun Shan Chun-xian guo Ru-guang Ma School of Materials Science and Engineering Suzhou University of Science and TechnologySuzhou215009China School of Instrumentation Science and Opto-electronics Engineering Beihang UniversityBeijing100083China

Oxygen reduction reaction(ORR) occurs at the cathode of fuel cells and metal-air batteries,but usually suffers from sluggish *** solve this issue,efficient electrocatalysts are highly ***(Pd)-based nanomaterials,as the most promising substitute of platinum(Pt),exhibit superior activity and stability in ORR *** delicate regulation of the structure and/or composition shows great potential in improving the electrocatalytic ORR performance of Pd-based *** this review,we retrospect the recent advance of Pdbased ORR electrocatalysts,and analyses the relationship between nanostructure and catalytic *** start with the ORR mechanism and indicators of ORR performance in both alkaline and acidic media,followed by the synthetic methods for Pd-based ***,we emphasize the design strategies of efficient Pd-based ORR catalysts from the perspective of composition,crystal phase,morphology,and support *** but not least,we conclude with possible opportunities and outlook on Pd-based nanomaterials toward ORR.

关键词： Oxygen reduction reaction(ORR) Palladium(Pd) Electrocatalyst Overpotential Reaction kinetics

Modeling and scenario prediction of a natural gas demand system based on a system dynamics method

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Petroleum Science 2018年第4期15卷 912-924页

作者： xian-Zhong Mu guo-Hao Li guang-Wen Hu Institute of Recycling Economy Beijing University of Technology

Based on the study of the relationship between structure and feedback of China’s natural gas demand system, this paper establishes a system dynamics model. In order to simulate the total demand and consumption structure of natural gas in China, we set up seven scenarios by changing some of the parameters of the model. The results showed that the total demand of natural gas would increase steadily year by year and reach in the range from 3600 to 4500 billion cubic meters in 2035. Furthermore, in terms of consumption structure, urban gas consumption would still be the largest term, followed by the gas consumption as industrial fuel, gas power generation and natural gas chemical industry. In addition, compared with the population growth, economic development still plays a dominant role in the natural gas demand growth, the impact of urbanization on urban gas consumption is significant, and the promotion of natural gas utilization technology can effectively reduce the total consumption of natural gas.

关键词： Natural gas demand system System dynamics Scenario prediction Consumption structure

Effect of Nb addition on microstructure and mechanical properties of 25CrNiMoV(DZ2)steel for high-speed railway axles

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Journal of Iron and Steel Research International 2022年第5期29卷 802-809页

作者： Jin-wen Zhang Yan-guang Cao Cheng-guo Zhang Zhao-dong Li Wen-xian Wang College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Technology Center Taiyuan Iron and Steel(Group)Co.Taiyuan030003ShanxiChina Department of Structural Steels Central Iron and Steel Research InstituteBeijing100081China Locomotive and Car Research Institute China Academy of Railway Sciences Corporation LimitedBeijing100081China

The microstructure,precipitates and properties of 25CrNiMoV(DZ2)steel for high-speed railway axles with different Nb contents were investigated by means of optical microscopy,scanning electron microscopy,electron back-scattering diffraction,transmission electron microscopy and physicochemical phase *** results show that the grain size of the original austenite of the test steels decreases from 20.5 to 14.2 and 10.8μm after adding 0.026 and 0.039 wt.%Nb to a 25CrNiMoV steel,***,the block width of the tempered martensite in the test steels is refined from 1.91 to 1.72 and 1.60µm,***-type precipitates in 25CrNiMoV steel are mainly VC,while(Nb,V)C gradually precipitates when Nb is microalloyed,and the amount of precipitates increases with increasing Nb *** strengthening mechanism analysis,it is found that grain refinement strengthening is the primary way to increase the *** improvement in the yield strength with increasing Nb content is attributed to a significant increase in precipitation strengthening,grain refinement strengthening and dislocation strengthening.

关键词： High-speed railway axle steel Nb microalloying Precipitate Strengthening mechanism

Study on Technologies for Information Monitoring and Quick Response of Agricultural Focuses and Significant Events

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Agricultural Sciences in China 2010年第5期9卷 764-770页

作者： ZHAO Rui-xue KOU Yuan-tao xian guo-jian MAO guang-wei Agricultural Information Institute Chinese Acedemy of Agricultural Sciences Beijing 100081 P.R.China

This article analyzed the importance of information monitoring and quick response on agricultural focuses and significant events, proposed the workflow and technical framework for information monitoring and quick response based on modern information technologies, and explained key technologies during implementation and the functional structure for prototype system of the technical support platform.

关键词： agricultural focus significant event information monitoring quick response technical platform