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Geochemistry and Genesis of the Late Jurassic Granitoids at Northern Great Hinggan Range:Implications for Exploration

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Acta Geologica Sinica(English Edition) 2010年第2期84卷 321-332页

作者： WU Guang CHEN Yanjing SUN Fengyue ZHANG Zhe LIU Ankun LI zhitong Key Laboratory of Metallogenic Dynamics Guangzhou Institute of Geochemistry the Chinese Academy of Sciences Guangzhou 510640 China Institute of Mineral Resources the Chinese Academy of Geological Sciences Beijing 100037 China Key Laboratory of Orogen and Crust Evolution Peking University Beijing 100871 China College of Earth Sciences Jilin University Changchun 130061 China Shenyang Institute of Geology and Mineral Resources China Geological Survey Shenyang 110032 China

The Longgouhe and Ershiyizhan intrusions of the Late Jurassic, located in the Upper Heilongjiang Basin of the northern Great Hinggan Range, are closely related to porphyry Cu-Au mineralizations. In lithology the intrusions are quartz diorite, quartz monzodiorite and granodiorite of high-K caIc-alkaline series, with minor aspects of shoshonite series. Their SiO2 and A1203 contents range from 61.37% to 66.59% and 15.35% to 17.06%, respectively. The MgO content ranges from 2.02 % to 3.47 %, with Mg# indices of 44-59. The （La/Yb）N and Eu/Eu＊ values range from 16.85 to 81.73 and 0.68 to 0.93, respectively, showing strong differentiation rare earth element （REE） patterns similar to those of adakites. The rocks are enriched in Ba, Sr and light REE （LREE）, obviously depleted in Nb and Ta, slightly depleted in Rb and Ti, and poor in Yb and Y, with Yb and Y contents of 0.31-1.32 ppm and 4.32-12.07 ppm, respectively. As indicated by Sr/Y ratios of 67.74-220.60, the rocks are characterized by low-Y and high-Sr contents, which characterize the adakites in the world. Holistically, geochemical tracers suggest that the interested intrusions are adakitic rocks. Given that the Paleo- Asian Ocean and Mongol-Okhotsk Ocean were closed in the Late Paleozoic and Permian-Middle Jurassic, respectively, the interested intrusions should be formed by partial melting of delaminated crust, which had been thickened during collisional orogeny between the Siberian and Mongolian- Sinokorean continents.

关键词： adakite geochemistry Late Jurassic continental collision thickened crust Great Hinggan Range

Incorporating transportation network modeling tools within transportation economic impact studies of disasters

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Journal of Traffic and Transportation Engineering(English Edition) 2014年第4期1卷 247-260页

作者： Yi Wen Li Zhang zhitong Huang Mingzhou Jin Department of Civil and Environmental Engineering Mississippi State University Department of Industrial and Systems Engineering University of Tennessee

Transportation system disruption due to a disaster results in ＂ripple effects＂ throughout the entire transportation system of a metropolitan region. Many researchers have focused on the economic costs of transportation system disruptions in transportation-related industries, specifically within commerce and logistics, in the assessment of the regional economic costs. However, the foundation of an assessment of the regional economic costs of a disaster needs to include the evaluation of consumer surplus in addition to the direct cost for reconstruction of the regional transportation system. The objective of this study is to propose a method to estimate the regional consumer surplus based on indirect economic costs of a disaster on intermodal transportation systems in the context of diverting vehicles and trains. The computational methods used to assess the regional indirect economic costs sustained by the highway and railroad system can utilize readily available state departments of transportation （DOTs） and metropolitan planning organizations （MPOs） traffic models allowing prioritization of regional recovery plans after a disaster and strengthening of infrastructure before a disaster. Hurricane Katrina is one of the most devastating hurricanes in the history of the United States. Due to the significance of Hurricane Katrina, a case study is presented to evaluate consumer surplus in the Gulf Coast Region of Mississippi. Results from the case study indicate the costs of rerouting and congestion delays in the regional highway system and the rent costs of fight-of-way in the regional railroad system are major factors of the indirect costs in the consumer surplus.

关键词： consumer surplus intermodal transportation economic impact disaster relief diverted traffic

元宇宙赋能体育健身产业:场景创设、多元价值与推进路径

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当代体育科技 2024年第5期14卷 84-86,132页

作者：周丽英王格张致铜王靖江华东交通大学体育健身研究中心华东交通大学体育与健康学院江西南昌330013

元宇宙技术的高速发展将推动体育健康行业数字化转型,深刻变革人们的生活。采用文献资料法和逻辑分析法,对元宇宙赋能体育健身产业的场景创设、多元价值与推进路径进行探析。研究认为,其在参与方式、教育方式与传播形式三方面具备现实价... 详细信息

元宇宙技术的高速发展将推动体育健康行业数字化转型,深刻变革人们的生活。采用文献资料法和逻辑分析法,对元宇宙赋能体育健身产业的场景创设、多元价值与推进路径进行探析。研究认为,其在参与方式、教育方式与传播形式三方面具备现实价值,并提出要推动理念更新、建立相应制度、促进技术优化与实践探索的推进路径。理性看待元宇宙,准确认识超前概念和现实技术之间的差异,同时构建完善运行规范,建立相应法律法规,提前策划元宇宙,以迎接新社会形态。

关键词：元宇宙健身产业数字技术推进路径

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CFRP/合金构件抽芯铆接成型机制及钉套变形区参数优化

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机床与液压 2024年第17期52卷 176-184页

作者：桂林景李皓周秩同胡建清王安康单垄垄张涵航天精工股份有限公司天津市紧固连接技术企业重点实验室天津300300 天津大学机械工程学院天津300354 中国直升机设计研究所江西景德镇300384

结合仿真及试验的方法,针对机械锁紧鼓包型抽芯铆钉的钉套变形区中高温区域的屈服强度和长度等参数对连接强度的影响规律进行研究。通过建立有限元仿真模型及试验验证,预测钉套变形区的鼓包成型形状与复合材料铆接结构的失效形式,并对... 详细信息

结合仿真及试验的方法,针对机械锁紧鼓包型抽芯铆钉的钉套变形区中高温区域的屈服强度和长度等参数对连接强度的影响规律进行研究。通过建立有限元仿真模型及试验验证,预测钉套变形区的鼓包成型形状与复合材料铆接结构的失效形式,并对铆接结构的承载性能变化规律进行分析。此外通过建立BP神经网络模型,得到了铆接结构最佳的钉套变形区中高温区域的屈服强度和长度等参数。结果表明:随着钉套构件高温区材料屈服强度的增加和长度的减少,铆接结构件鼓包成型装配力逐渐提升,同时铆接结构也出现承载力峰值,这主要与拉伸过程中鼓包成型区域的变形和复合材料的损伤有关。

关键词：复合材料铆接成型有限元仿真 BP神经网络

牛分枝杆菌Ag85B的生物信息学分析及多表位候选抗原的构建

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黑龙江畜牧兽医 2024年第15期 62-65,72,118,119页

作者：董希望张岩魏稚彤李文欣刘思宇梁栋赵海涛河南农业大学动物科技学院郑州450002 河南省鲁山县畜牧技术推广站河南平顶山467399

为了构建基于牛分枝杆菌Ag85B蛋白的多表位候选抗原,试验采用生物信息学方法对Ag85B蛋白的理化性质、亲/疏水性、二级结构等进行分析,预测其T、B淋巴细胞抗原表位,并构建以pET-28a(+)为载体的多表位候选抗原,分析预测多表位候选抗原的... 详细信息

为了构建基于牛分枝杆菌Ag85B蛋白的多表位候选抗原,试验采用生物信息学方法对Ag85B蛋白的理化性质、亲/疏水性、二级结构等进行分析,预测其T、B淋巴细胞抗原表位,并构建以pET-28a(+)为载体的多表位候选抗原,分析预测多表位候选抗原的理化性质、抗原性并进行免疫模拟。结果表明:Ag85B蛋白有325个氨基酸残基,相对分子量为34.58085,理论等电点为5.62,脂肪系数为72.18,亚细胞定位于线粒体、细胞质和高尔基体中,具有亲水性、信号肽和跨膜结构域,属于分泌型蛋白,其无规则卷曲和β-转角结构的占比分别28.15%和8.62%,含有3个T淋巴细胞优势表位和8个B淋巴细胞优势表位。构建的Ag85B多表位候选抗原为亲水性蛋白和非致敏原,两次预测免疫原性参数分别为0.893和1.524,可诱导特异性的体液和细胞免疫应答。说明试验成功构建出基于牛分枝杆菌Ag85B蛋白的多表位候选抗原,且该多表位候选抗原可能诱导机体产生T、B淋巴细胞免疫应答。

关键词：牛分枝杆菌抗原表位 Ag85B 生物信息学多表位候选抗原

秸秆还田方式对土壤理化性质和玉米产量的影响

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中国生态农业学报（中英文） 2024年第4期32卷 663-674页

作者：王治统凌俊刘子熙赵德强李泽学周顺利袁兴茂李霄鹤温媛中国农业大学农学院北京100193 河北省农业机械化研究所有限公司石家庄050051

高强度集约化农业生产导致耕地质量下降、农田土壤退化,而秸秆还田是改善土壤环境、提高土壤有机质的重要途径。目前的秸秆还田方式主要针对表层土壤,忽略了对底土质量的改善效果。本研究设置了秸秆富集深层还田、秸秆覆盖还田、秸秆浅... 详细信息

高强度集约化农业生产导致耕地质量下降、农田土壤退化,而秸秆还田是改善土壤环境、提高土壤有机质的重要途径。目前的秸秆还田方式主要针对表层土壤,忽略了对底土质量的改善效果。本研究设置了秸秆富集深层还田、秸秆覆盖还田、秸秆浅旋还田、秸秆深翻还田、秸秆不还田5种秸秆还田方式,以探究不同秸秆还田方式对不同土层土壤理化性质和玉米产量的影响,为高效利用秸秆资源、提高土壤质量和作物产量提供科学依据。本研究结果表明:秸秆覆盖还田提高了0~20 cm土层土壤含水量、有机碳含量、氮循环酶活性;深翻还田提高了表层土壤水分含量与磷循环酶活性;秸秆富集深层还田显著降低了20~40 cm土层土壤容重、增加了土壤含水量、有机碳含量、全氮含量、矿质氮含量以及胞外酶活性。与不还田相比,秸秆还田处理下玉米产量显著提高13.4%~21.0%。因此,秸秆还田是秸秆资源有效利用的重要方式,有利于改善农田土壤环境,提高土壤养分含量,减少化肥使用,促进作物增产,对农业可持续发展具有重要意义。秸秆富集深层还田对于改善底土质量,扩大土壤碳库,提高耕地质量和土地生产力具有重要作用,可以作为构建深厚肥沃耕层的有效措施。

关键词：秸秆还田土壤理化性质玉米产量土壤酶秸秆富集深层还田

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In-situ encapsulation ofα-Fe_(2)O_(3) nanoparticles into ZnFe_(2)O_(4) micro-sized capsules as high-performance lithium-ion battery anodes

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Journal of Materials Science & Technology 2021年第16期75卷 110-117页

作者： Wei Wu Yongshan Wei Hongjiang Chen Keyan Wei zhitong Li Jianhui He Libo Deng Lei Yao Haitao Yang Shenzhen Key Laboratory of Special Functional Materials Shenzhen Engineering Laboratory for Advanced Technology of CeramicsGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Transition metal oxides as anode materials for high-performance lithium-ion batteries suffer from severe capacity decay,originating primarily from particle pulverization upon volume expansion/shrinkage and the intrinsically sluggish electron/ion ***,in-situ encapsulation ofα-Fe_(2)O_(3) nanoparticles into micro-sized ZnFe_(2)O_(4) capsules is facilely fulfilled through a co-precipitation process and followed by heat-treatment at optimal calcination *** porous ZnFe_(2)O_(4) scaffold affords a synergistic confinement effect to suppress the grain growth ofα-Fe2 O3 nanocrystals during the calcination process and to accommodate the stress generated by volume expansion during the charge/discharge process,leading to an enhanced interfacial conductivity and inhibit electrode pulverization and mechanical failure in the active *** these merits,the preparedα-Fe_(2)O_(3)/Fe_(2)O_(4) composite delivers prolonged cycling stability and improved rate capability with a higher specific capacity than soleα-Fe_(2)O_(3) and Fe_(2)O_(4).The discharge capacity is retained at 700 mAh g-1 after 500 cycles at 200 mA g^(-1) and 940 mAh g^(-1) after 50 cycles at 100 m A g^(-1).This work provides a new perspective in designing transition metal oxides for advanced lithium-ion batteries with superior electrochemical properties.

关键词： α-Fe_(2)O_(3)/ZnFe_(2)O_(4)ceramic composite Co-precipitation process Confinement effect Interfacial effect Grain growth High conductivity Lithium-ion battery anodes

Energy saving analysis of a transparent radiative cooling film for buildings with roof glazing

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能源与人工环境(英文) 2021年第2期2卷 214-222页

作者： zhitong Yi Yingyan lv Dikai Xu Jingtao Xu Hua Qian Dongliang Zhao Ronggui Yang Ningbo Ruiling Advanced Energy Materials Institute Co. LtdNingbo 315500China School of Energy and Environment Southeast UniversityNanjing 210096China Engineering Research Center of Building Equipment Energyand EnvironmentMinistry of EducationChina School of Energy and Power Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Coal Combustion Huazhong University of Science and TechnologyWuhan 430074China

A transparent radiative cooling(T-RC)film with low transmittance in solar spectra and selectively high emissivity in the atmospheric window(8-13𝜇m)is applied on roof glazing for building energy *** evaluate the per-formance of the T-RC film,two identical model boxes(1.0 m×0.6 m×1.2 m,L×W×H)were constructed and the inside air temperatures were measured in August in Ningbo,*** show that the maximum temperature difference between the two model boxes with and without the T-RC film was 21.6℃during the experiment.A whole building model was built in EnergyPlus for the model *** a good agreement achieved between the calculation results and the measured temperature data,the experimentally validated EnergyPlus model was then extended to an 815.1 m^(2)exhibition building with roof glazing to analyze the annual air conditioning(AC)energy *** results show that by incorporating both the T-RC film’s cooling benefit in summer and heating penalty in winter,the annual AC energy consumption of the exhibition building can be reduced by 40.9-63.4%,varying with different climate conditions.

关键词： Transparent radiative cooling film Spectrum selective Window film Building energy saving

SiC含量对SiC_(p)/2009Al复合材料微观组织及力学性能的影响

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金属热处理 2024年第6期49卷 190-197页

作者：肖治同王方明颜泽华张勇曹振呼怀刚李炯利王旭东北京石墨烯技术研究院有限公司北京100094 北京石油机械有限公司北京102206 哈尔滨理工大学荣成学院山东威海264300 中国航发北京航空材料研究院北京100095 油气钻完井技术国家工程研究中心北京102206

通过在2009Al合金中引入不同质量分数(0、1%、3%、5%)的SiC颗粒,采用热等静压工艺制备了SiC_(p)/2009Al复合材料,随后进行了热挤压和固溶时效处理,研究了工艺过程对该复合材料组织与性能的影响。结果表明,采用热等静压工艺能够制备出晶... 详细信息

通过在2009Al合金中引入不同质量分数(0、1%、3%、5%)的SiC颗粒,采用热等静压工艺制备了SiC_(p)/2009Al复合材料,随后进行了热挤压和固溶时效处理,研究了工艺过程对该复合材料组织与性能的影响。结果表明,采用热等静压工艺能够制备出晶粒均匀且SiC分散均匀的复合材料,SiC颗粒与Al基体界面结合良好;经挤压工艺后,复合材料的微观组织明显改变,增强体SiC颗粒破碎并细化,当SiC含量较低(≤3%)时SiC颗粒沿挤压流均匀分布在基体中,SiC较高(>3%)时,SiC颗粒存在轻微的团聚现象。经固溶时效处理后,基体晶粒尺寸的均匀性提高,析出的第二相细小均匀弥散分布在基体中。通过对SiC_(p)/2009Al复合材料进行热挤压及固溶时效处理可以得到较优的综合力学性能。当引入质量分数为3%的SiC时,复合材料的力学性能更佳,其抗拉强度为492.7 MPa,屈服强度为400.9 MPa,断后伸长率为12.7%,硬度为131 HBW,在室温下兼具较好的耐磨性能。

关键词： SiC_(p)/2009Al复合材料热等静压力学性能耐磨性能