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火焰法制备非晶态“实心”炭纳米纤维的结构模型及其电输运行为

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新型炭材料 2014年第6期29卷 473-480页

作者：祁祥孟兆楷潘春旭武汉大学物理科学与技术学院湖北武汉430072 湘潭大学材料与光电物理学院湖南湘潭411105 武汉大学教育部人工微纳结构重点实验室湖北武汉430072

火焰法制备的非晶态"实心"炭纳米纤维内部原子排列无序紊乱,依靠常规的表征手段,难以得到其三维原子构型分布。根据非晶态"实心"炭纳米纤维的XRD图谱提供的衍射强度数据,采用逆向蒙特卡罗法,重构了非晶态"实心"炭纳米纤维的微观原子构型... 详细信息

火焰法制备的非晶态"实心"炭纳米纤维内部原子排列无序紊乱,依靠常规的表征手段,难以得到其三维原子构型分布。根据非晶态"实心"炭纳米纤维的XRD图谱提供的衍射强度数据,采用逆向蒙特卡罗法,重构了非晶态"实心"炭纳米纤维的微观原子构型,并对获得的模型进行充分的误差分析。计算得到了非晶态炭纳米纤维的费米能级及其导电机制,认为其具有半导体特征;实验测量单根非晶态"实心"炭纳米纤维的电输运行为发现,其I-V曲线呈现对称和非线性特征,且电阻随着温度的升高而下降,进一步证明非晶态"实心"炭纳米纤维的原子构型具有一定的真实性。

关键词：炭纳米纤维非晶态逆向蒙特卡罗法电输运行为

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埕岛中心三号平台密闭集输系统的调控与改造

石化技术 2016年第3期23卷 95-96页

作者：孟昭凯中石化胜利油田分公司海洋采油厂山东东营257000

埕岛中心三号平台是胜利油田第一座密闭集输的海上中心平台,具备良好的安全环保和节能效益。但在实际应用中存在溢油风险高、气蚀严重、调控能力弱等问题。两年来,平台进行了多方面探索,认为通过合理布局、混输泵和变频技术以及科学的... 详细信息

埕岛中心三号平台是胜利油田第一座密闭集输的海上中心平台,具备良好的安全环保和节能效益。但在实际应用中存在溢油风险高、气蚀严重、调控能力弱等问题。两年来,平台进行了多方面探索,认为通过合理布局、混输泵和变频技术以及科学的系统调控,能够实现密闭集输系统的稳定运行。

关键词：浅海油田密闭集输系统压力调整

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千里寻慕容

今日辽宁 2007年第3期 72-74页

作者：孟昭凯

　　寻找慕容鲜卑后裔的活动始于2007年1月.当时,朝阳市政府邀请《人民日报》、《光明日报》、《民族画报》等多家媒体,15名记者到朝阳采访考察.领队陆辉先生提出在全国开展一次寻找慕容后裔的活动.回北京后,他首先从网上发布了消息.朝... 详细信息

　　寻找慕容鲜卑后裔的活动始于2007年1月.当时,朝阳市政府邀请《人民日报》、《光明日报》、《民族画报》等多家媒体,15名记者到朝阳采访考察.领队陆辉先生提出在全国开展一次寻找慕容后裔的活动.回北京后,他首先从网上发布了消息.朝阳三燕文化研究会立即响应,建立了三燕文化网站.……

关键词：金鸡山三燕文化

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推进林业生态建设促进防沙治沙进程

现代农业研究 2021年第5期27卷 114-115页

作者：孟召开永昌县花草滩林场甘肃金昌737200

本文简要叙述了林业生态建设的现状,并且提出了优化的具体措施,以期为林业建设人员提供借鉴参考,使其从根源出发,总结有效的治沙经验,坚持综合治理的原则,以及遵循以人为本的思想观念,发展沙产业。同时,制定生态建设发展方案,增强防沙... 详细信息

本文简要叙述了林业生态建设的现状,并且提出了优化的具体措施,以期为林业建设人员提供借鉴参考,使其从根源出发,总结有效的治沙经验,坚持综合治理的原则,以及遵循以人为本的思想观念,发展沙产业。同时,制定生态建设发展方案,增强防沙和治沙的效果,达到治理的总体目标,从而促进国家林业建设的发展。

关键词：长远规划沙产业生态建设

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氯化锂-氯化钾熔盐中二氧化铈的熔解还原

无机盐工业 2016年第10期48卷 16-19页

作者：黄一飞孟照凯林如山贾艳虹何辉林铭章中国科学技术大学核科学技术学院安徽合肥230026 中国原子能科学研究院放射化学研究所中国科学院核能安全技术研究所

熔盐电解技术是乏燃料干法后处理的重要技术路线。以二氧化铈为氧化物乏燃料的模拟物,探索了氧化物乏燃料在氯化锂-氯化钾熔盐体系中的熔解问题,研究了各参数(温度、时间、流速等)对氯化反应的影响,成功使用液态锌阴极回收熔盐中低浓度... 详细信息

熔盐电解技术是乏燃料干法后处理的重要技术路线。以二氧化铈为氧化物乏燃料的模拟物,探索了氧化物乏燃料在氯化锂-氯化钾熔盐体系中的熔解问题,研究了各参数(温度、时间、流速等)对氯化反应的影响,成功使用液态锌阴极回收熔盐中低浓度的铈,通过真空减压蒸馏成功实现了铈-锌合金的分离,为乏燃料的干法后处理提供了有参考价值的基础数据。

关键词：熔盐 CeO2 氯化还原

Paleoenvironment evolution of the East Philippine Sea recorded in the new-type ferromanganese crust since the terminal Late Miocene

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Science China Earth Sciences 2007年第8期50卷 1179-1188页

作者： XU zhaokai LI AnChun JIANG FuQing LI TieGang meng QingYong JIN Ning Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China Graduate University of Chinese Academy of Sciences Beijing 100039China

From systemic research of microstructure, geochemistry, uranium-series and 10Be isotope dating on a new-type deepwater ferromanganese crust from the East Philippine Sea, the paleoenvironment evolu-tion of the target area since the terminal Late Miocene was recovered. The vertical section changes of microstructure and chemical composition are consistent in the studied crust, which indicate three major accretion periods and corresponding paleoenvironment evolution of the crust. The bottom crust zone was formed in the terminal Late Miocene (5.6 Ma) with loose microstructure, high detritus content and high growth rate. Reductions of mineral element content, accretion rate and positive Ce-anomaly degree at 4.6 Ma indicate temporal warming, which went against the crust accretion and finally formed an accretion gap in the terminal Middle Pliocene (2.8―2.7 Ma). The more active Antarctic bottom sea-waters in the Late Pliocene (2.7 Ma) facilitated the fast transfer to the top pure crust zone. Hereafter, with the further apart of volcanic source and the keeping increase of eolian material (1.0 Ma), although surrounding conditions were still favorable, mineral element content still shows an obvious reducing trend. It thereby offers new carrier and data for the unclear paleoceanographic research of the target area since the terminal Late Miocene.

关键词： new-type ferromanganese crust record paleoenvironment evolution uranium-series dating 10Be isotope dating East Philippine Sea

KCl-NaCl等摩尔熔盐体系电解CeCl_3制备金属铈

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广东化工 2017年第9期44卷 100-103页

作者：顾炜华肖益群贾艳虹孟照凯林如山中国原子能科学研究院放射化学研究所北京102413

KCl-NaCl等摩尔熔盐体系是常见的高温熔盐体系。相比于LiCl-KCl共晶盐体系,KCl-NaCl等摩尔熔盐体系允许的操作温度更高,从而可以将金属转变为液态,以便收集。本文在850℃条件下电解CeCl_3-KCL-NaCl熔盐,以99.3%的产率制备了金属铈。金... 详细信息

KCl-NaCl等摩尔熔盐体系是常见的高温熔盐体系。相比于LiCl-KCl共晶盐体系,KCl-NaCl等摩尔熔盐体系允许的操作温度更高,从而可以将金属转变为液态,以便收集。本文在850℃条件下电解CeCl_3-KCL-NaCl熔盐,以99.3%的产率制备了金属铈。金属铈在坩埚底部直接获得并与熔盐快速脱模,经ICP-AES分析金属的纯度大于99.17%,EDS分析金属纯度大于99.9%。实验建立了电解过程化学模型,解释了电解效率关于电流大小的变化趋势,电流效率最高时使用的电流为3 A(电流密度为0.6821 A/cm^2)。电解过程使用搅拌桨将导致液态金属铈过度分散而无法收集。

关键词： KCl-NaCl熔盐铈金属制备电解

Climate evolution of southwest Australia in the Miocene and its main controlling factors

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Science China Earth Sciences 2022年第6期65卷 1104-1115页

作者： Tianqi SUN zhaokai XU Fengming CHANG Tiegang LI Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266061China University of Chinese Academy of Sciences Beijing 100049China CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Key Laboratory of Marine Sedimentology and Metallogeny First Institute of OceanographyMNRQingdao 266061China

At present, the seasonal melting and expansion of the Antarctic ice sheet affect the location and intensification of the westerlies, as well as the precipitation and continental weathering and erosion in southwest Australia. The Miocene was an important period when the Earth's climate state transitioned from a warmhouse to an icehouse and the East Antarctic Ice Sheet underwent large-scale melting and expansion. At that time, Australia was closer to the Antarctic region than it is now. This makes Australia an ideal target area for studying the coupling relationship among the atmosphere, hydrosphere, lithosphere, and cryosphere. Based on the comprehensive analysis of the siliciclastic mass accumulation rate, grain size, clay minerals, and elemental composition of the sediments at Site U1516 of the International Ocean Discovery Program Expedition 369, we reconstructed the Miocene climate evolution and the continental weathering and erosion history of southwest Australia on a tectonic time scale. Our indicators show that the climate was dry and that continental weathering and erosion were weak, with a small amount of terrestrial material transported to the ocean during the Early to Middle Miocene(22–12.7 Ma). However, as mentioned in previous studies of nearby sites, precipitation and river runoff increased prominently with enhanced continental weathering at 12.7–8 Ma, which was related to the northward migration or intensification of the westerlies, possibly due to increased sea ice in the Southern Ocean. In addition, we found that the evolution of the South Asian monsoon and the westerly belt were synchronized in the Miocene, which indicates that the South Asian monsoon system at that time may also have been affected by the high-latitude signals of the Southern Hemisphere. We speculate that the significant decrease in deep-sea temperature and the expansion of the surface sea temperature gradient in latitude and longitude until the permanent East Antarctic Ice Sheet fo

关键词： Miocene Southwest Australia Climate evolution Controlling factors International ocean discovery program

Molecular phylogenetics of Gymnocypris (Teleostei: Cyprinidae) in Lake Qinghai and adjacent drainages

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Chinese Science Bulletin 2005年第13期50卷 1325-1333页

作者： zhaokai LIJunbing YANGGongshe DUANZiyuan HEShunping CHENYiyu InstituteofHydrobiology ChineseAcademyofSciencesWuhan430072China//AgricultureandAnimalHusbandryCollegeQinghaiUniversityXining810003China InstituteofHydrobiology ChineseAcademyofSciencesWuhan430072China LaboratoryofAnimalFatDepositionandMuscleDevelopment NorthwestSci-techUniversityofAgricultureandForestryYangling712100China InstituteofGeneticsandDevelopmentalBiology ChineseAcademyofSciencesBeijing100101China

149 complete mitochondrial DNA (mtDNA) cytochrome b (Cyt b) genes (1140 bp) of Gymnocypris przewalskii, Gymnocypris eckloni and Gymnocypris scolisto-mus from the Lake Qinghai, Yellow River and Qaidam Basin were sequenced and analyzed. Consistent dendrogram indi-cated that the samples collected from the same species do not constitute a separate monophyletic group and all the samples were grouped into three highly divergent lineages (A, B and C). Among them, Lineage A contained all samples of G. przewalskii from the Lake Qinghai and partial samples of the G. eckloni from the Yellow River. Lineage B contained the remaining samples of G. eckloni from the Yellow River. Lineage C was composed of a monophyletic group by G. eck-loni from the Qaidam Basin. Analysis of molecular variance (AMOVA) indicated that most of genetic variations were detected within these three mtDNA lineages (93.12%), sug-gesting that there are three different lineages of Gymnocypris in this region. Our Cyt b sequence data showed that G. przewalskii was not a polytypic species, and G. scolistomus was neither an independent species nor a subspecies of G. eckloni. The divergent mtDNA lineages of G. eckloni from the Yellow River suggested that gene flow between the different populations was restricted to a certain extent by several gorges on the upper reach of the Yellow River. Lineage B of G. eckloni might be the genetic effect from the ancestor which was incorporated with the endemic schizothoracine fishes when the headward erosion of the Yellow River reached to its current headwaters of late. The G. eckloni from Basin Qaidam was a monophyletic group (lineage C) and Fst values within G. eckloni from the Yellow River were higher than 0.98, suggesting that the gene flow has been interrupted for a long time and the G. eckloni from Basin Qaidam might have been evolved into different species by ecology segrega-tion. The correlation between the rakers number of Gymno-cypris and population genetic variation

关键词：分子学系统发生学细胞色素 DNA