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基于FIP的HXD2系列电力机车智能运维数据云平台研究与设计 被引量:1
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作者 陈广泰 陈闯 +2 位作者 姜正 王超 杜海宾 《计算机应用与软件》 北大核心 2024年第4期34-37,66,共5页
基于自主研制的FIP网络车载数据采集传输装置为载体,结合当前先进的4G APN无线通信、5G定点转储技术,提出一套适合基于FIP网络的HXD2系列电力机车智能运维数据云平台研究与设计,阐述系统功能、硬件组成、数据转存机制和试用情况,实现对H... 基于自主研制的FIP网络车载数据采集传输装置为载体,结合当前先进的4G APN无线通信、5G定点转储技术,提出一套适合基于FIP网络的HXD2系列电力机车智能运维数据云平台研究与设计,阐述系统功能、硬件组成、数据转存机制和试用情况,实现对HXD2系列电力机车的远程运行状态监测及记录文件的定点转储,为机车运用部门提供了高效的信息化手段和大数据支撑手段。 展开更多
关键词 HXD2系列电力机车 fip网络 5G转储 远程监测 智能运维 云平台
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Dynamic response mechanism and precursor characteristics of gneiss rockburst under different initial burial depths 被引量:1
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作者 LIU Dongqiao SUN Jie +4 位作者 MENG Wen HE Manchao ZHANG Chongyuan LI Ran CAO Binghao 《Journal of Mountain Science》 SCIE CSCD 2024年第3期1004-1018,共15页
To investigate the influence mechanism of geostress on rockburst characteristics,three groups of gneiss rockburst experiments were conducted under different initial geostress conditions.A high-speed photography system... To investigate the influence mechanism of geostress on rockburst characteristics,three groups of gneiss rockburst experiments were conducted under different initial geostress conditions.A high-speed photography system and acoustic emission(AE)monitoring system were used to monitor the entire rockburst process in real time.The experimental results show that when the initial burial depth increases from 928 m to 1320 m,the proportion of large fracture scale in rockburst increases by 154.54%,and the AE energy increases by 565.63%,reflecting that the degree and severity of rockburst increase with the increase of burial depth.And then,two mechanisms are proposed to explain this effect,including(i)the increase of initial geostress improves the energy storage capacity of gneiss,and then,the excess energy which can be converted into kinetic energy of debris ejection increases,consequently,a more pronounced violent ejection phenomenon is observed at rockburst;(ii)the increase of initial geostress causes more sufficient plate cracks of gneiss after unloading ofσh,which provides a basis for more severe ejection of rockburst.What’s more,a precursor with clear physical meaning for rockburst is proposed under the framework of dynamic response process of crack evolution.Finally,potential value in long term rockburst warning of the precursor obtained in this study is shown via the comparison of conventional precursor. 展开更多
关键词 Traffic Engineering Gneiss Rockburst Crack propagation Excess energy precursor characteristic
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基于FIP模式的“环境土壤学”教改实践
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作者 金超 张妙月 +1 位作者 曹英杰 王诗忠 《教育教学论坛》 2024年第40期5-10,共6页
针对新时代环境科学专业本科生专业型、国际化人才培养的需求,对“环境土壤学”课程教学进行改革,并基于“三位一体”课程体系提出FIP教学模式:F为frontier,意为紧追学术前沿,将科研工作与教学融合;I为international,意为国际化教学,拓... 针对新时代环境科学专业本科生专业型、国际化人才培养的需求,对“环境土壤学”课程教学进行改革,并基于“三位一体”课程体系提出FIP教学模式:F为frontier,意为紧追学术前沿,将科研工作与教学融合;I为international,意为国际化教学,拓宽学生学术视野;P为practice,意为课外研习实践,引导学生自主实施研究性学习项目。以FIP模式为指导,建立了融基础内容与学科研究前沿知识为一体的“环境土壤学”课程教学体系。上述教改思路提高了学生学习的主动性与科研实践能力,促进了高素质土壤修复人才的培养,并建立了“环境土壤学”精品课程及卓越的教学团队,学生对本次教学改革的总体满意程度为100%,为开设类似课程的高校提供了参考。 展开更多
关键词 环境土壤学 “三位一体”课程体系 fip教学模式
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Disinfection Byproducts and Their Precursors in Drinking Water Sources:Origins,Influencing Factors,and Environmental Insights 被引量:1
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作者 Rong Xiao Yang Deng +1 位作者 Zuxin Xu Wenhai Chu 《Engineering》 SCIE EI CAS CSCD 2024年第5期36-50,共15页
Tracing the contamination origins in water sources and identifying the impacts of natural and human processes are essential for ecological safety and public health.However,current analysis approaches are not ideal,as ... Tracing the contamination origins in water sources and identifying the impacts of natural and human processes are essential for ecological safety and public health.However,current analysis approaches are not ideal,as they tend to be laborious,time-consuming,or technically difficult.Disinfection byproducts(DBPs)are a family of well-known secondary pollutants formed by the reactions of chemical disinfectants with DBP precursors during water disinfection treatment.Since DBP precursors have various origins(e.g.,natural,domestic,industrial,and agricultural sources),and since the formation of DBPs from different precursors in the presence of specific disinfectants is distinctive,we argue that DBPs and DBP precursors can serve as alternative indicators to assess the contamination in water sources and identify pollution origins.After providing a retrospective of the origins of DBPs and DBP precursors,as well as the specific formation patterns of DBPs from different precursors,this article presents an overview of the impacts of various natural and anthropogenic factors on DBPs and DBP precursors in drinking water sources.In practice,the DBPs(i.e.,their concentration and speciation)originally present in source water and the DBP precursors determined using DBP formation potential tests—in which water samples are dosed with a stoichiometric excess of specific disinfectants in order to maximize DBP formation under certain reaction conditions—can be considered as alternative metrics.When jointly used with other water quality parameters(e.g.,dissolved organic carbon,dissolved organic nitrogen,fluorescence,and molecular weight distribution)and specific contaminants of emerging concern(e.g.,certain pharmaceuticals and personal care products),DBPs and DBP precursors in drinking water sources can provide a more comprehensive picture of water pollution for better managing water resources and ensuring human health. 展开更多
关键词 Disinfection byproducts Disinfection byproduct precursors Drinking water sources Contamination indicator Natural factors Human factors
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稳定表达FIP1L1-PDGFRA及其突变体细胞株的构建和耐药性评价
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作者 刘婧雯 宋昊昕 朱蕾 《基础医学与临床》 2024年第1期63-68,共6页
目的构建能稳定表达FIP1L1-PDGFRA融合基因(F/P)及其T674I和D842V突变体的小鼠原B细胞株BaF3-F/P、BaF3-F/P-T674I和BaF3-F/P-D842V,并通过考察它们对酪氨酸激酶抑制剂(TKIs)的响应以评价其活性。方法用慢病毒感染技术将目的基因导入BaF... 目的构建能稳定表达FIP1L1-PDGFRA融合基因(F/P)及其T674I和D842V突变体的小鼠原B细胞株BaF3-F/P、BaF3-F/P-T674I和BaF3-F/P-D842V,并通过考察它们对酪氨酸激酶抑制剂(TKIs)的响应以评价其活性。方法用慢病毒感染技术将目的基因导入BaF3细胞;RT-qPCR检测mRNA表达;CCK-8法检测TKIs对稳转细胞株增殖的抑制作用。结果构建的BaF3-F/P、BaF3-F/P-T674I和BaF3-F/P-D842V细胞株均能转录FIP1L1和PDGFRA mRNA,并表现出不依赖IL-3增殖的恶性表型特征以及对相应TKIs的敏感性。结论成功构建了能稳定表达F/P及其T674I、D842V突变体的小鼠原B细胞株,为开发以此为靶点的化合物提供良好的细胞模型。 展开更多
关键词 fip1L1-PDGFRA融合基因 基因突变 慢病毒载体 BaF3细胞 慢性嗜酸粒细胞白血病
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TAX1BP1 and FIP200 orchestrate non-canonical autophagy of p62 aggregates for mouse neural stem cell maintenance
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作者 Yi-Fu Zhu Rong-Hua Yu +15 位作者 Shuai Zhou Pei-Pei Tang Rui Zhang Yu-Xin Wu Ran Xu Jia-Ming Wei Ying-Ying Wang Jia-Li Zhang Meng-Ke Li Xiao-Jing Shi Yu-Wei Zhang Guang-Zhi Liu Rick FThorne Xu Dong Zhang Mian Wu Song Chen 《Zoological Research》 SCIE CSCD 2024年第4期937-950,共14页
Autophagy plays a pivotal role in diverse biological processes,including the maintenance and differentiation of neural stem cells(NSCs).Interestingly,while complete deletion of Fip200 severely impairs NSC maintenance ... Autophagy plays a pivotal role in diverse biological processes,including the maintenance and differentiation of neural stem cells(NSCs).Interestingly,while complete deletion of Fip200 severely impairs NSC maintenance and differentiation,inhibiting canonical autophagy via deletion of core genes,such as Atg5,Atg16l1,and Atg7,or blockade of canonical interactions between FIP200 and ATG13(designated as FIP200-4A mutant or FIP200 KI)does not produce comparable detrimental effects.This highlights the likely critical involvement of the non-canonical functions of FIP200,the mechanisms of which have remained elusive.Here,utilizing genetic mouse models,we demonstrated that FIP200 mediates non-canonical autophagic degradation of p62/sequestome1,primarily via TAX1BP1 in NSCs.Conditional deletion of Tax1bp1 in fip200hGFAP conditional knock-in(cKI)mice led to NSC deficiency,resembling the fip200hGFAP conditional knockout(cKO)mouse phenotype.Notably,reintroducing wild-type TAX1BP1 not only restored the maintenance of NSCs derived from tax1bp1-knockout fip200hGFAP cKI mice but also led to a marked reduction in p62 aggregate accumulation.Conversely,a TAX1BP1 mutant incapable of binding to FIP200 or NBR1/p62 failed to achieve this restoration.Furthermore,conditional deletion of Tax1bp1 in fip200hGFAP cKO mice exacerbated NSC deficiency and p62 aggregate accumulation compared to fip200hGFAP cKO mice.Collectively,these findings illustrate the essential role of the FIP200-TAX1BP1 axis in mediating the non-canonical autophagic degradation of p62 aggregates towards NSC maintenance and function,presenting novel therapeutic targets for neurodegenerative diseases. 展开更多
关键词 Non-canonical autophagy TAX1BP1 fip200 P62 AGGREGATES Neural stem cell
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Investigation of granite failure precursor under axial load using modified LSTM framework
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作者 WANG Ya-lei XU Jin-ming 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2930-2943,共14页
Granite is usually composed of quartz,biotite,feldspar,and cracks,and the variation characteristics of these components could reflect the deformation and failure process of rock well.Taking granite as an example,the v... Granite is usually composed of quartz,biotite,feldspar,and cracks,and the variation characteristics of these components could reflect the deformation and failure process of rock well.Taking granite as an example,the video camera was used to record the deformation and failure process of rock.The distribution of meso-components in video images was then identified.The meso-components of rock failure precursors were also discussed.Moreover,a modified LSTM(long short-term memory method)based on SSA(sparrow search algorithm)was proposed to estimate the change of meso-components of rock failure precursor.It shows that the initiation and expansion of cracks are mainly caused by feldspar and quartz fracture,and when the quartz and feldspar exit the stress framework,rock failure occurs;the second large increase of crack area and the second large decrease of quartz or feldspar area may be used as a precursor of rock failure;the precursor time of rock failure based on meso-scopic components is about 4 s earlier than that observed by the naked eye;the modified LSTM network has the strongest estimation ability for quartz area change,followed by feldspar and biotite,and has the worst estimation ability for cracks;when using the modified LSTM network to predict the precursors of rock instability and failure,quartz and feldspar could be given priority.The results presented herein may provide reference in the investigation of rock failure mechanism. 展开更多
关键词 GRANITE failure precursor axial load modified long short-term memory method
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Stabilizing perovskite precursors with the reductive natural amino acid for printable mesoscopic perovskite solar cells
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作者 Wenjing Hu Jian Yang +9 位作者 Chuang Yang Xufeng Xiao Chaoyang Wang Zhaozhen Cui Qiaojiao Gao Jianhang Qi Minghao Xia Yaqiong Su Anyi Mei Hongwei Han 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期32-39,I0003,共9页
Solution processability significantly advances the development of highly-efficient perovskite solar cells.However,the precursor solution tends to undergo irreversible degradation reactions,impairing the device perform... Solution processability significantly advances the development of highly-efficient perovskite solar cells.However,the precursor solution tends to undergo irreversible degradation reactions,impairing the device performance and reproducibility.Here,we utilize a reductive natural amino acid,Nacetylcysteine(NALC),to stabilize the precursor solution for printable carbon-based hole-conductorfree mesoscopic perovskite solar cells.We find that I_(2) can be generated in the aged solution containing methylammonium iodide(MI) in an inert atmosphere and speed up the MA-FA^(+)(formamidinium) reaction which produces large-size cations and hinders the formation of perovskite phase.NALC effectively stabilizes the precursor via its sulfhydryl group which reduces I_(2) back to I^(-)and provides H^(+).The NALC-stabilized precursor which is aged for 1440 h leads to devices with a power conversion efficiency equivalent to 98% of that for devices prepared with the fresh precursor.Furthermore,NALC improves the device power conversion efficiency from 16.16% to 18.41% along with enhanced stability under atmospheric conditions by modifying grain boundaries in perovskite films and reducing associated defects. 展开更多
关键词 Perovskite solar cells Perovskite precursor Degradation STABILIZATION Reductive natural amino acid
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Precursor engineering enables high-performance all-inorganic CsPbIBr_(2) perovskite solar cells with a record efficiency approaching 13%
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作者 Qingyan Chang Yidan An +8 位作者 Huaiman Cao Yuzhen Pan Liangyu Zhao Yulong Chen Yi We Sai-Wing Tsang Hin-Lap Yip Licheng Sun Ze Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期16-22,I0003,共8页
All-inorganic CsPbIBr_(2) perovskite has attracted widespread attention in photovoltaic and other optoelectronic devices because of its superior thermal stability.However,the deposition of high-quality solutionprocess... All-inorganic CsPbIBr_(2) perovskite has attracted widespread attention in photovoltaic and other optoelectronic devices because of its superior thermal stability.However,the deposition of high-quality solutionprocessed CsPbIBr_(2) perovskite films with large thicknesses remains challenging.Here,we develop a triple-component precursor(TCP) by employing lead bromide,lead iodide,and cesium bromide,to replace the most commonly used double-component precursor(DCP) consisting of lead bromide and cesium iodide.Remarkably,the TCP system significantly increases the solution concentration to 1.3 M,leading to a larger film thickness(~390 nm) and enhanced light absorption.The resultant CsPbIBr_(2) films were evaluated in planar n-i-p structured solar cells,which exhibit a considerably higher optimal photocurrent density of 11.50 mA cm^(-2) in comparison to that of DCP-based devices(10.69 mA cm^(-2)).By adopting an organic surface passivator,the maximum device efficiency using TCP is further boosted to a record efficiency of 12.8% for CsPbIBr_(2) perovskite solar cells. 展开更多
关键词 All-inorganic perovskite solar cells CsPbIBr_(2) precursor engineering Solubility High performance
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Numerical Simulation of the Mechanical Stirring Process in a Tannin-Based Foaming Precursor Resin
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作者 Lan Huang Wenbin Yuan +2 位作者 Hisham Essawy Xiaojian Zhou Xinyi Chen 《Fluid Dynamics & Materials Processing》 EI 2024年第10期2219-2234,共16页
Tannin foam is a new functional material.It can be widely applied to the automobile industry,construction industry,and packaging industry due to its wide range of raw materials,renewable,easily degraded,low cost and a... Tannin foam is a new functional material.It can be widely applied to the automobile industry,construction industry,and packaging industry due to its wide range of raw materials,renewable,easily degraded,low cost and almost no pollution.Preparing tannin foam is a very complex process that includes high temperature,two phases,mechanical agitation,and phase change.To investigate the influence of the stirring velocity and paddle shape,simulation was calculated by making use of the volume of fluid(VOF)method and multiple reference frame(MRF)method in a three-dimensional flow field of tannin-based foaming precursor resin.The gas holdup and velocity magnitude were analysed with various conditions of mechanical velocities and paddle shape in the stirring flow field.The result shows the higher the velocity,the greater the disturbance and paddle shape between the eggbeater and the Rushton turbine,obviously the paddle shape of the eggbeater with a wider range of agitation,which can entrap more air into the tannin-based foaming precursor resin in a short time.Especially when the speed is 1500 rpm,the flow field of the Rushton turbine comes out of a ditch,which decreases the efficiency of mass transfer;there is less air to mix into the tannin-based foaming precursor resin,which causes unevenness.At the same time,the eggbeater shows the marvelous capability of hybrid as it has two vortexes and multiple cycles that make a difference from the Rushton turbine,which has only one vortex and two upper and lower loops;the structure makes the flow field more stable allowed evenness of flow field tannin-based foaming precursor resin.The results reveal that it is beneficial for tannin-based foaming precursor resin to use an eggbeater with a speed of 1500 rpm to reduce the consumption of resources while obtaining a uniform flow field. 展开更多
关键词 Tannin-based foaming precursor resin mechanical agitation numerical simulation volume of fluid(VOF) multiple reference frame(MRF)
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Highly Defective Dark TiO_(2) Modified with Pt: Effects of Precursor Nature and Preparation Method on Photocatalytic Properties
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作者 E.D.Fakhrutdinova O.A.Reutova +6 位作者 T.A.Bugrova I.Yu.Ovsyuk L.S.Kibis O.A.Stonkus D.B.Vasilchenko O.V.Vodyankina V.A.Svetlychnyi 《Transactions of Tianjin University》 EI CAS 2024年第2期198-209,共12页
The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibite... The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed CO adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (OH) _(2) (NO _(3) ) _(8) ] were used. The sample featured a high content of single-atom species and subnano-sized Pt clusters. The X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (SMSI) eff ect of the transfer of electron density from the electron-saturated defects on the TiO _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the SMSI eff ect, exhibited the highest photocatalytic activity. The 0.5Pt(C)/TiO_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation. 展开更多
关键词 Dark(black)TiO_(2) Pulsed laser ablation Platinum reduction method precursor type PHOTOCATALYSIS Hydrogen evolution reaction
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从2009到2022:FIP邮政历史展品评审指导要点的变化与感悟
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作者 祝建国 《上海集邮》 2024年第9期34-36,共3页
本文将对比分析2009年1月1日和2022年5月FIP发布的两份邮政历史展品评审指导要点,探讨它们在展品定义、类别划分、评审标准等方面的异同,为参展者提供一些组集建议。
关键词 指导要点 类别划分 评审标准 参展者 fip 对比分析 展品
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2023年和2014年FIP一框展品评审指导要点比较
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作者 祝建国 《上海集邮》 2024年第11期44-45,共2页
尽管在新评审指导要点结尾的修改说明中写道:“2023年5月28日在德国埃森举行的第76届FIP大会上,两位FIP成员提出的修改一框展品评审指导要点的动议获得通过,条件是进行微小的修改。”但比较新旧指导要点,可以看出修改的内容还是不少的,... 尽管在新评审指导要点结尾的修改说明中写道:“2023年5月28日在德国埃森举行的第76届FIP大会上,两位FIP成员提出的修改一框展品评审指导要点的动议获得通过,条件是进行微小的修改。”但比较新旧指导要点,可以看出修改的内容还是不少的,下面我们来逐条进行对比和分析。 展开更多
关键词 指导要点 修改说明 德国埃森 fip 评审 对比和分析 展品
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从1995到2022:FIP航空集邮展品评审指导要点的变化与感悟
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作者 祝建国 《上海集邮》 2024年第10期30-32,共3页
仔细阅读和比较2022年和1995年新旧两份航空集邮展品评审指导要点,笔者发现FIP航空集邮委员会新发布的评审指导要点,实际上已将评审专用规则(SREV)和评审指导要点合二为一了,它包含了原SREV和评审指导要点中的所有内容,为航空集邮展品... 仔细阅读和比较2022年和1995年新旧两份航空集邮展品评审指导要点,笔者发现FIP航空集邮委员会新发布的评审指导要点,实际上已将评审专用规则(SREV)和评审指导要点合二为一了,它包含了原SREV和评审指导要点中的所有内容,为航空集邮展品的评审提供了更加明确的指导。新评审指导要点不仅展现了航空集邮的发展趋势,也体现了航空集邮界对展品评审标准的不断完善和细化。 展开更多
关键词 指导要点 评审标准 集邮 fip 合二为一 SRE 发展趋势 仔细阅读
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辽南丹东地区中生代金成矿的FIP证据 被引量:16
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作者 倪培 范建国 +1 位作者 田京辉 周进 《岩石学报》 SCIE EI CAS CSCD 北大核心 2000年第4期506-512,共7页
辽南丹东地区产出有五龙、四道沟两个大型金矿床。两矿床与中生代燕山期三股流花岗岩体存在密切的空间伴生关系。长期以来 ,对这一地区金的成矿作用时代存在有不同的认识。一种观点认为金的成矿作用只有一期 ,即中生代 (燕山期 ) ;另一... 辽南丹东地区产出有五龙、四道沟两个大型金矿床。两矿床与中生代燕山期三股流花岗岩体存在密切的空间伴生关系。长期以来 ,对这一地区金的成矿作用时代存在有不同的认识。一种观点认为金的成矿作用只有一期 ,即中生代 (燕山期 ) ;另一种观点认为金的成矿作用有两期 ,即元古代和中生代 (燕山期 ) ,分别以四道沟金矿和五龙金矿为代表。作者利用流体包裹体面 (FIP)研究的新方法对金矿床及伴生花岗岩进行了研究 ,结果表明 ,三股流花岗岩的 FIP最优势定向方位与五龙金矿、四道沟金矿床含金石英脉的 FIP最优势定向方位一致 ;FIP中的流体是自下而上运移的 ;FIP中的流体是捕获于花岗岩成岩期和金矿床成矿期的流体 ;花岗岩的成岩与金矿床成矿流体形成于相同的区域应力场下 ,其捕获时间基本一致 ,与丹东地区的中生代构造热事件相吻合。 FIP的研究结果支持了丹东地区统一的中生代金成矿模式。实践证明 ,FIP是研究成矿作用的一种新的、有效的手段 ,在成岩、成脉 (矿 ) 展开更多
关键词 fip优势定向 区域应力场 金矿床 成矿作用
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血清LDH、CRP及NT-proBNP水平与危重先天性心脏病新生儿术后心功能的相关性
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作者 邱潇 董玉斌 +1 位作者 罗英媚 阚晓婧 《中西医结合心脑血管病杂志》 2025年第2期278-281,共4页
目的:分析血清乳酸脱氢酶(LDH)、C反应蛋白(CRP)及N末端脑钠肽前体(NT-proBNP)水平与危重先天性心脏病(CCHD)新生儿术后心功能的相关性。方法:选取在周口市中心医院确诊并接受手术治疗的65例CCHD新生儿为研究组,同期在本院出生体检健康... 目的:分析血清乳酸脱氢酶(LDH)、C反应蛋白(CRP)及N末端脑钠肽前体(NT-proBNP)水平与危重先天性心脏病(CCHD)新生儿术后心功能的相关性。方法:选取在周口市中心医院确诊并接受手术治疗的65例CCHD新生儿为研究组,同期在本院出生体检健康的新生儿65名作为对照组。收集研究对象临床资料,采用酶联免疫吸附法检测血清CRP、NT-proBNP水平;酶偶联法检测血清LDH水平;彩色超声仪测量患儿左室短轴缩短率(LVFS)、左室射血分数(LVEF)评估CCHD患儿术后心功能。比较术后不同心功能分级患儿血清LDH、CRP、NT-proBNP水平;分析术前血清LDH、CRP、NT-proBNP水平与患儿术后心功能的相关性。结果:研究组血清LDH、CRP、NT-proBNP水平高于对照组(P<0.001)。Ⅰ级组、Ⅱ级组、Ⅲ级组患儿血清LDH、CRP、NT-proBNP水平逐渐升高,LVFS、LVEF逐渐降低(P<0.05)。Pearson相关性分析显示,CCHD患儿血清LDH、CRP、NT-proBNP水平与LVFS、LVEF呈负相关(P<0.05)。心功能Ⅲ级组和心功能Ⅰ级或Ⅱ级组患儿疾病类型、入院体重比较,差异均有统计学意义(P<0.05)。进一步多因素Logistic回归分析显示,血清LDH、NT-proBNP水平是CCHD患儿术后心功能Ⅲ级的影响因素(P<0.05)。结论:CCHD患儿血清LDH、CRP、NT-proBNP水平呈高表达,与心功能呈负相关,LDH、NT-proBNP是心功能Ⅲ级发生的影响因素,可作为临床预测CCHD患儿术后心功能的潜在指标。 展开更多
关键词 先天性心脏病 N末端脑钠肽前体 心功能 乳酸脱氢酶 C反应蛋白 相关性
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Pyrolysis mechanism of ZrC precursor and fabrication of C/C-ZrC composites by precursor infiltration and pyrolysis 被引量:5
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作者 刘春轩 陈建勋 +3 位作者 苏哲安 杨鑫 曹柳絮 黄启忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1779-1784,共6页
C/C-ZrC composites were prepared by precursor infiltration and pyrolysis using the organic zirconium as precursor.The conversion mechanisms of the precursors such as the thermal behavior,structural evolution,phase com... C/C-ZrC composites were prepared by precursor infiltration and pyrolysis using the organic zirconium as precursor.The conversion mechanisms of the precursors such as the thermal behavior,structural evolution,phase composition,microstructure,composition of the precursors and products were analyzed by thermal gravimetric analyzer,Fourier transform infrared spectrometer,X-ray diffraction and scanning electron microscope.The results indicate that the ZrC precursor transforms to inorganic ZrO2 from room temperature to 1200 ℃,then reduces to ZrC at 1600 ℃ through the carbothermal reduction reaction.The microstructure of the C/C-ZrC composites was also investigated.The composites exhibit an interesting structure,a coating composed of ZrC ceramic covers the exterior of the composite,and the ZrC ceramic is embedded in the pores of the matrix inside the composite. 展开更多
关键词 ZrC precursor pyrolysis mechanism precursor infiltration and pyrolysis C/C-ZrC composites
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河南刘山岩铜锌矿床石英中流体包裹体类型及FIP新资料 被引量:3
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作者 韦昌山 杨振强 +1 位作者 黄惠兰 付建明 《华南地质与矿产》 CAS 2004年第4期15-21,共7页
在刘山岩矿床矿石和围岩石英所含的流体包裹体中,发现2种新类型流体包裹体,即后期变形阶段的淡化水流体包裹体和成岩早期的NaCl子矿物多相包裹体,并重点研究了流体包裹体面(FIP)中包裹体发育情况。块状铜锌矿石、条带状矿石和糜棱岩化... 在刘山岩矿床矿石和围岩石英所含的流体包裹体中,发现2种新类型流体包裹体,即后期变形阶段的淡化水流体包裹体和成岩早期的NaCl子矿物多相包裹体,并重点研究了流体包裹体面(FIP)中包裹体发育情况。块状铜锌矿石、条带状矿石和糜棱岩化石英角斑岩中FIP特别发育,通常FIP以高角度与石英的拉长方向相交(或垂直于岩石的叶理面)。FIP中大多数流体包裹体具有中温(均一温度120~220℃)、中盐度(3.4%~14.5%)。更重要的是:FIP中普遍含有低盐度(3.4%~6.4%),部分甚至含有更低盐度(0.2%~1.7%)的淡化水流体包裹体,这表明淡化水流体(或大气降水)在造山变形后期曾经参与过FIP古流体的活动。 展开更多
关键词 流体包裹体 流体包裹体面(fip) 淡化水流体包裹体 刘山岩
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Precursor solution prepared by evaporation deamination complex method for solvent separation of Mo and W by H_2O_2-complexation 被引量:7
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作者 关文娟 张贵清 高从堦 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期1139-1146,共8页
An novel method on preparation of precursor solution for solvent separation of molybdenum (Mo) and tungsten (W) by hydrogen peroxide (H2O2)-complexation from the ammonium tungstate solution containing high Mo wa... An novel method on preparation of precursor solution for solvent separation of molybdenum (Mo) and tungsten (W) by hydrogen peroxide (H2O2)-complexation from the ammonium tungstate solution containing high Mo was studied. The precursor solution was obtained via evaporation deamination and H202-complex transformation processes. Then it was extracted with a mixture extractant of tri-alkyl phosphine oxide (TRPO) and tributyl phosphate (TBP) to separate Mo and W. The results indicated that the evaporation deamination complex method reduced the acid consumption by more than 90% in comparison with the traditional directly acid regulation complex method. The transformation rates of W and Mo were higher than 95% and the decomposition rate of H202 was less than 15% at a 1.8-1.9 times H202 dosage, 45-50 ℃, initial pH of 1.80-1.90, and transformation volume ratio of 100% for 60 min in the H2O2-complexation transformation process. The minimum extraction rate of W was 2%, the maximum extraction rate of Mo was 82.6% and the highest separation coefficient was 76.7 in a single-stage extraction. 展开更多
关键词 TUNGSTEN MOLYBDENUM solvent extraction separation precursor solution H202
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带有双重容量限制的FIP问题研究 被引量:7
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作者 杨珺 杨超 马云峰 《中国公路学报》 EI CAS CSCD 北大核心 2004年第4期85-88,共4页
研究了一类特殊的FIP(FlowInterceptionProblem)问题。在假设顾客最多只被截取一次的条件下,考虑如何进行工作站选址使工作站截取的路径上的用户量最大,即经过工作站的流量总和最大。在给定的网络G(N,A)中已知每个O D对用户分配在各路... 研究了一类特殊的FIP(FlowInterceptionProblem)问题。在假设顾客最多只被截取一次的条件下,考虑如何进行工作站选址使工作站截取的路径上的用户量最大,即经过工作站的流量总和最大。在给定的网络G(N,A)中已知每个O D对用户分配在各路线上的用户流量fp,在一定费用预算下,考虑了工作站设站的最小截取容量和最大工作容量双重限制条件下的FIP问题,将这一问题形成一个线性的混合整数规划模型。在此基础上给出了启发式算法,并通过启发式算法和分支定界法对一个算例进行计算比较。 展开更多
关键词 交通工程 截流问题 启发式算法 容量 模型
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