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Chinese Journal of Chemistry 2023年第22期41卷 2995-3002,I0002页

作者： Xiaowei Pan changjiang wu Huayi Fang Chunhua Yan School of Materials Science and Engineering Tianjin Key Lab for Rare Earth Materials and ApplicationsNankai University Tianjin300350China Shanghai Zhitong Construction Engineering Technology Co. Ltd.Shanghai 204433China College of Chemistry and Chemical Engineering Lanzhou UniversityLanzhouGansu 730000China

Recent decades have witnessed a rapid development of the lanthanide silicon chemistry.In this research,by reacting[(THF)_(3)LisiPh_(3)]with Cp_(3)Ln(Ⅰ)(THF)(Ln(I)=Sm(Ⅰ),Tb(Ⅱ),Dy(Ⅰ),Yb(Ⅰ)or Cp_(2)Lu(Ⅱ)CI(THF),a series of middle-and heavy-lanthanocene monosilyl/disilyl ate-complexes([(DME)_(3)Lil[Cp_(3)Ln(Ⅱ)SiPh_(3)]and[(DME)_(3)Li[Cp_(2)Lu(Ⅱ)(SiPh_(3))_(2)])were synthesized.The structures of the obtained lanthanocene monosilyl/disilyl ate-complexes were determined by single crystal X-ray diffraction.Together with the previously reported[(DME)_(3)Li[Cp_(3)La(Ⅱ)SiPh_(3)]and[(DME);Lil[Cp_(3)Ce(Ⅱ)SiPha],a complex group comprising silyl light-,middle-and heavy-lanthanocene with identical core coordination pattern are presented.

关键词： Lanthanide ate-complex Silyl ligand Lanthanide-silicon bond Structure elucidation Density functional calculations Metallocenes

Global land 1° mapping dataset of XCO_(2) from satellite observations of GOSAT and OCO-2 from 2009 to 2020

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Big Earth Data 2023年第1期7卷 170-190页

作者： Mengya Sheng Liping Lei Zhao-Cheng Zeng Weiqiang Rao Hao Songd changjiang wu Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina College of Resources and Environment University of Chinese Academy of SciencesBeijingChina Division of Geological and Planetary Sciences California Institute of TechnologyPasadenaCaliforniaUSA School of Earth Sciences China University of GeosciencesBeijingChina

A global mapping data of atmospheric carbon dioxide(CO_(2))concen-trations can help us to better understand the spatiotemporal varia-tions of CO_(2) and the driving factors of the variations to support the actions for emissions reduction and control.Greenhouse gases satel-lites that measure atmospheric CO_(2),such as the Greenhouse Gases Observing Satellite(GOSAT)and Orbiting Carbon Observatory(OCO-2),have been providing global observations of the column averaged dry-air mole fractions of CO_(2)(XCO_(2))since 2009.However,these XCO_(2) retrievals are irregular in space and time with many gaps.In this paper,we mapped a global spatiotemporally continuous XCO_(2) data-set(Mapping-XCO_(2))using the XCO_(2) retrievals from GOSAT and OCO-2 during the period from April 2009 to December 2020 based on a geostatistical approach that fills those data gaps.The dataset covers a geographic range from 56°S to 65°N and 169°W to 180°E for a 1°grid interval in space and 3-day time interval.The uncer-tainties of the mapped XCO_(2) values are generally less than 1.5 parts per million(ppm).The spatiotemporal characteristics of global XCO_(2) that are revealed by the Mapping-XCO_(2) are similar to the model data obtained from CarbonTracker.Compared to the ground observa-tions,the overall standard bias is 1.13 ppm.The results indicate that this long-term Mapping-XCO_(2) dataset can be used to investigate the spatiotemporal variations of global atmospheric XCO_(2) and can support studies related to the carbon cycle and anthropogenic CO_(2) emissions.The dataset is available at http://***/10.7910/DVN/4WDTD8 and https://***/en/detail?dataSetId=c2c3111b421043fc8d9b163c39e6f56e.

关键词： Global land mapping atmospheric CO_(2)column concentration satellite observation GOSAT OCO-2

Ethylene Copolymerization with Linear and End-Cyclized Olefins via a Metallocene Catalyst:Polymerization Behavior and Thermal Properties of Copolymers

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Engineering 2023年第11期30卷 93-99页

作者： changjiang wu Minqiao Ren Liping Hou Shuzhang Qu Xinwei Li Cui Zheng Jian Chen Wei Wang SINOPEC(Beijing)Research Institute of Chemical Industry Co. Ltd.Beijing 100013China

Olefin solution polymerization can be used to obtain high-performance polyolefin materials that cannot be obtained via other polymerization processes.Polyolefin elastomers(POE)are a typical example.Due to cost,only a few linear a-olefins(e.g.,1-butene,1-hexene,and 1-octene)are used as comonomers in solution polymerization in industry.However,a-olefin comonomers with other structures may have different effects on polymerization in comparison with common linear ones.Moreover,the properties of the corresponding materials may differ significantly.In this work,copolymers of ethylene with linear and endcyclized a-olefins are synthesized using a metallocene catalyst.The copolymerization of ethylene with linear a-olefins results in a higher turn-over frequency(TOF)and lower incorporation than copolymerization with end-cyclized a-olefins,which may indicate that end-cyclized a-olefins have a higher coordination probability and lower insertion rate.In this reaction,the comonomer is distributed randomly in the polymer chain and efficiently destroys crystallization.End-cyclized a-olefins exhibit a much stronger crystallization destructive capacity(CDC)in the copolymer than linear a-olefins,possibly because linear a-olefins act mainly in the radial direction of the main chain of the polymer,while end-cyclized a-olefins act mainly in the axial direction of the main chain.

关键词： Metallocene catalyst Ethylene copolymerization Comonomer distribution Crystallization destructive capacity

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我国绿色化工技术现状与发展建议

石油炼制与化工 2024年第1期55卷 68-81页

作者：吴长江中石化(北京)化工研究院有限公司北京100013

化学工业的快速发展,促进了全球的经济增长,提高了人民的生活质量,但随着化工生产过程中化石能源的大量消耗,也带来无法忽视的环境污染和气候变化等问题。中国主动提出“双碳”目标,要求各行各业走绿色高质量发展之路,促进我国化工行业... 详细信息

化学工业的快速发展,促进了全球的经济增长,提高了人民的生活质量,但随着化工生产过程中化石能源的大量消耗,也带来无法忽视的环境污染和气候变化等问题。中国主动提出“双碳”目标,要求各行各业走绿色高质量发展之路,促进我国化工行业的绿色转型。绿色化工应包括从化工原料、催化剂、反应工程、能源到产品的全产业链和创新链的绿色化,是行业发展的大势所趋。建议加强对绿色化工技术应用基础研究导向性支持,提倡将绿色指标纳入技术先进性评价标准,推动绿色发展理念融入化工产业技术开发与应用全过程,加速我国化工行业通过数字化转型和一体化发展,早日实现更多绿色化工技术革新和行业的可持续发展。

关键词：绿色化工绿色催化剂化工过程强化绿色产品

Bicontinuous porous membranes with micro-nano composite structure using a facile atomization-assisted nonsolvent induced phase separation method

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Frontiers of Chemical Science and Engineering 2022年第8期16卷 1268-1280页

作者： Jing Wang Guoyuan Pan Yu Li Yang Zhang Hongwei Shi Xuanbo Liu Hao Yu Muhua Zhao Yiqun Liu changjiang wu College of Materials Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China SINOPEC Beijing Research Institute of Chemical Industry Beijing 100013China

The micro-nano composite structure can endow separation membranes with special surface properties,but it often has the problems of inefficient preparation process and poor structural stability.In this work,a novel atomization-assisted nonsolvent induced phase separation method,which is also highly efficient and very simple,has been developed.By using this method,a bicontinuous porous microfiltration membrane with robust micro-nano composite structure was obtained via commercially available polymers of polyacrylonitrile and polyvinylpyrrolidone.The formation mechanism of the micro-nano composite structure was proposed.The microphase separation of polyacrylonitrile and polyvinylpyrrolidone components during the atomization pretreatment process and the hydrogen bonding between polyacrylonitrile and polyvinylpyrrolidone molecules should have resulted in the nano-protrusions on the membrane skeleton.The membrane exhibits superhydrophilicity in air and superoleophobicity underwater.The membrane can separate both surfactant-free and surfactant-stabilized oil-in-water emulsions with high separation efficiency and permeation flux.With excellent antifouling property and robust microstructure,the membrane can easily be recycled for long-term separation.Furthermore,the scale-up verification from laboratory preparation to continuous production has been achieved.The simple,efficient,cost-effective preparation method and excellent membrane properties indicate the great potential of the developed membranes in practical applications.

关键词： atomization nonsolvent induced phase

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公路勘察设计中存在的问题及对策

中国科技纵横 2024年第4期 111-113页

作者：吴昌江云南省交通勘察设计研究院有限公司云南昆明 650000

随着经济的发展,公路建设行业和公路运输行业迅速发展.在行业进步的同时,必须密切关注公路勘察设计中涉及的各种要求和内容,否则可能会对公路建设和运输造成安全隐患.基于新形势,探讨公路工程勘察设计面临的问题以及对应措施.

关键词：新形势公路勘察设计问题对策

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智能仪表预测性维护关键技术

仪表技术与传感器 2024年第4期 29-37页

作者：王成城王金江张来斌王凯邬长江中国石油大学(北京)安全与海洋工程学院机械工业仪器仪表综合技术经济研究所应急管理部油气生产安全与应急技术重点实验室

智能仪表是大型工业过程和复杂装备系统传感与控制的“神经”,其健康状态直接影响系统的安全可靠运行。传统的智能仪表通常作为测量工具监测工艺过程和重点装备的运行状态,本体故障的忽视极易导致采集数据不准确、不可靠,影响工业过程... 详细信息

智能仪表是大型工业过程和复杂装备系统传感与控制的“神经”,其健康状态直接影响系统的安全可靠运行。传统的智能仪表通常作为测量工具监测工艺过程和重点装备的运行状态,本体故障的忽视极易导致采集数据不准确、不可靠,影响工业过程管控效率,也易导致操作人员误判,从而引发安全事故。文中通过对智能仪表预测性维护的技术架构进行解析,建立了机理分析、数据采集、特征分析、故障自检、异常检测、故障诊断和寿命预测的技术路线,同时,从复杂工业过程视角将智能仪表分解为“传输”、“传感”和“传递”,总结了仪表本体级和系统级预测性维护的关键技术,分析了智能运维、安全仪表风险管控、信息安全风险管控3种典型应用场景,推演了诊断自组态和云边协同架构的技术发展趋势。研究可为智能仪表及系统运维由离线向在线、由预防性维护向预测性维护的转变奠定基础。

关键词：智能仪表预测性维护异常检测故障诊断寿命预测

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基于专利视角的磷矿浮选药剂研究分析

化工设计通讯 2024年第5期50卷 15-21页

作者：程卫红吴长江高芳裙武汉工程大学图书馆湖北武汉430205

磷矿资源是国家不可再生的战略资源,中低品位胶磷矿为主的分布特征和磷资源需求第一大国的现状决定了我国磷矿亟须高效能磷矿选矿。中低品位磷矿石需要选矿富集后才能用于农业和工业生产,浮选药剂是磷矿浮选能否取得良好指标的关键。利... 详细信息

磷矿资源是国家不可再生的战略资源,中低品位胶磷矿为主的分布特征和磷资源需求第一大国的现状决定了我国磷矿亟须高效能磷矿选矿。中低品位磷矿石需要选矿富集后才能用于农业和工业生产,浮选药剂是磷矿浮选能否取得良好指标的关键。利用Patentics专利数据库,从专利文献计量学角度对磷矿浮选药剂专利进行了系统检索与统计分析,对专利申请趋势、专利价值、专利创新主体分布和合作网络、专利技术路线等研究现状展开全面分析,剖析目前存在问题并提出相应建议。

关键词：磷矿浮选药剂捕收剂调整剂创新主体

川中中台山地区致密砂岩储层层序特征及有利区优选

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特种油气藏 2024年第2期31卷 84-92页

作者：郑超邱玉超文龙李楠吴长江张晓丽陈双玲袁纯中国石油西南油气田分公司四川成都610000

川中中台山地区须三下亚段(须三下)层序构成差异性明显、河流相砂体横向变化较快,层序地层划分较为困难,进而影响优质储层的识别与刻画。为此,基于测井、录井和地震资料,分析中台山地区须三下层序特征,圈定不同朵页体的分布范围,对储层... 详细信息

川中中台山地区须三下亚段(须三下)层序构成差异性明显、河流相砂体横向变化较快,层序地层划分较为困难,进而影响优质储层的识别与刻画。为此,基于测井、录井和地震资料,分析中台山地区须三下层序特征,圈定不同朵页体的分布范围,对储层有利区进行优选。结果表明:川中中台山地区须三下地层沉积继承了须二上亚段的地层特征,为东南高西北低、洼中隆的缓坡古构造背景,共识别出3期层序界面和2期湖泛面;致密砂岩储层矿物组分主要为岩屑和长石,孔隙类型以溶蚀孔隙、微裂缝为主;岩性组合主要有厚层砂岩组合、厚层砂夹薄层泥岩组合和厚层泥夹薄层砂岩组合三大类;结合高产井具有断裂、裂缝、储层发育,位于构造相对高部位的特征,将研究区储层划分为3类有利区。研究成果可为后续的勘探开发提供重要参考和理论支撑。

关键词：致密砂岩层序特征储层预测须三下中台山地区

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高流动性聚酰胺6的热降解研究

现代塑料加工应用 2024年第2期36卷 1-4页

作者：黄逸伦赵嘉玮王兴国初立秋高达利吴长江中石化(北京)化工研究院有限公司北京100013

采用热重分析法研究了高流动性聚酰胺6(PA6)在氮气(N_(2))和氧气(O_(2))氛围中的热降解动力学,确定了其热降解机理类型。结果表明:不同升温速率下,PA6在N_(2)中的热降解过程为一步反应,在O_(2)中为二步反应。高温环境中聚合物在O_(2)中... 详细信息

采用热重分析法研究了高流动性聚酰胺6(PA6)在氮气(N_(2))和氧气(O_(2))氛围中的热降解动力学,确定了其热降解机理类型。结果表明:不同升温速率下,PA6在N_(2)中的热降解过程为一步反应,在O_(2)中为二步反应。高温环境中聚合物在O_(2)中的初始降解温度、最大失重速率温度和终止降解温度均低于无氧环境,并且这些特征降解温度在N_(2)和O_(2)氛围中均随升温速率的提高而升高。通过Flynn-Wall-Ozawa(FWO)、Kissinger-Akahira-Sunose(KAS)和Tang 3种拟合方法确定了PA6在N_(2)和O_(2)中的平均热降解活化能分别为258.22 kJ/mol和224.36 kJ/mol,并通过与Coats-Redfern法计算得到不同机理函数时的活化能对比,确定了PA6在N_(2)和O_(2)中的热降解机理函数类型为随机成核后生长的三级减速型(F3型)。

关键词：聚酰胺6 热降解活化能动力学