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新时代金融监管体系助力公司核保研究

商业观察 2024年第14期10卷 96-99页

作者：孙彦敏兰州财经大学金融学院甘肃兰州730030

随着当前经济环境发生变化,金融风险源头以及性质也产生了改变,不断加强和完善现代金融监管、强化金融稳定保障体系是形势所趋,我国金融监管迎来新时代改革,也推进了对保险销售行为管理的进一步加强。核保行为在保险销售过程链中处于关... 详细信息

随着当前经济环境发生变化,金融风险源头以及性质也产生了改变,不断加强和完善现代金融监管、强化金融稳定保障体系是形势所趋,我国金融监管迎来新时代改革,也推进了对保险销售行为管理的进一步加强。核保行为在保险销售过程链中处于关键地位,是保险公司用于风险管理的防护屏障。随着新时代金融监管体系不断完善,保险产品的核保风险管控对于保险公司经营来说具有重要地位。文章通过对金融监管与保险公司核保行为相关理论进行研究,分析我国目前核保行为存在的问题,进而提出完善金融监管体系助力公司核保行为的对策建议。

关键词：公司核保金融监管制度社会主义特色

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不同烧制气氛对丙烯酸催化剂性质影响的研究

无机盐工业 2024年第9期56卷 164-170页

作者：王静苏晋张利杰周鹏孙彦民李佳中海油天津化工研究设计院有限公司天津300131

采用溶液法制备了含Mo-V的复合氧化物前驱体,经喷雾干燥后的前驱体在不同气氛(5%H_(2)+95%N_(2)、N_(2)、5%O_(2)+95%N_(2)、空气和O_(2))中焙烧处理,获得Mo-V-W-Sb系列复合金属氧化物催化剂,并将其应用于丙烯醛气相氧化制丙烯酸反应。... 详细信息

采用溶液法制备了含Mo-V的复合氧化物前驱体,经喷雾干燥后的前驱体在不同气氛(5%H_(2)+95%N_(2)、N_(2)、5%O_(2)+95%N_(2)、空气和O_(2))中焙烧处理,获得Mo-V-W-Sb系列复合金属氧化物催化剂,并将其应用于丙烯醛气相氧化制丙烯酸反应。采用电感耦合等离子体发射光谱仪(ICP-OES)、X射线荧光光谱仪(XRF)、X射线衍射仪(XRD)、氮气物理吸附仪、透射电子显微镜(TEM)、化学吸附仪和电位滴定仪对催化剂进行了表征。实验结果表明,不同的焙烧气氛对Mo-V-W-Sb系列催化剂的晶相结构、物化性质及催化性能均产生了明显的影响。前驱体在弱氧化性气氛(5%O_(2)+95%N_(2))中烧制时,有利于制备出含有较纯Mo_(3)VO_(11+x)活性相、相对较大比表面积(6.8 m^(2)/g)、适中结晶度和还原温度(约415℃),以及最适宜n(V^(5+))[/n(V^(3+))+n(V^(4+))+n(V^(5+))]为0.019的催化剂,且该催化剂表现出最佳的催化性能,高达99.5%的丙烯醛转化率和88.7%的丙烯酸收率。

关键词：复合氧化物气相氧化丙烯酸催化性能

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大庆SN油田东部过渡带油水边界综合确定

新疆石油地质 2024年第2期45卷 213-220页

作者：梁宇杨会东付宪弟蔡东梅王彦辉孙衍民中国石油大庆油田有限责任公司勘探开发研究院黑龙江大庆163712

为确定大庆SN油田东部过渡带油水界面,综合钻井、测井、地震资料,结合岩心含油产状分析和老井油水层二次解释,基于双相介质理论的叠后属性油气检测以及基于叠前地震波形指示反演的流体识别等技术,探讨构造油气藏外扩区油水边界的综合确... 详细信息

为确定大庆SN油田东部过渡带油水界面,综合钻井、测井、地震资料,结合岩心含油产状分析和老井油水层二次解释,基于双相介质理论的叠后属性油气检测以及基于叠前地震波形指示反演的流体识别等技术,探讨构造油气藏外扩区油水边界的综合确定方法。研究区油水边界具有以下特征:岩心含油产状为油斑以上;测井解释外推为油层或油水同层;叠后属性低高频能量比大于0.85;叠前反演预测含水饱和度小于75%。因此,以“井点定深度、地震定边界、动态来验证”为原则,从“点—线—面—空”,经过综合分析,确定最终油水边界位置。研究成果有效指导了研究区外扩评价部署,对同类型构造油田油水边界研究具有参考意义。

关键词：构造油气藏油水边界井震资料叠后属性叠前反演综合分析

Synthesis of hexagonal and triangular Fe3O4 nanosheets via seed-mediated solvothermal growth

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Nano Research 2014年第4期7卷 536-543页

作者： Chunhui Li Ruixue Wei yanmin Xu Ailing sun Liuhe Wei College of Chemistry and Molecular Engineering Zhengzhou Key Laboratory of Elastic Sealing Materials Zhengzhou UniversityZhengzhou 450001 China

Hexagonal and triangular monodisperse Fe3O4 nanosheets have been synthesized via a two-step microemulsion solvothermal approach in which uniform Fe3O4 nanoparticles are first prepared and then these hydrophobic nanocrystals are dispersed in a uniform microemulsion environment as ＂seeds＂ for further re-growth through a secondary solvothermal process. The growth of anisotropic morphologies has been explained by the presence and orientation of twin planes in the face-centered cubic Fe3O4 which direct the shape of the growing particles. In particular, reentrant grooves resulting from twin planes are favorable sites for the addition of adatoms, leading to anisotropic growth. Triangular nanosheets are believed to contain one twin face which directs the growth of the primary particles in two dimensions. Hexagonal nanosheets are believed to contain two parallel planes that allow the growth edges to regenerate one another. The growth mechanism is evidenced by the analysis of high-resolution transmission electron microscopy （HRTEM） results and the as-prepared Fe3O4 nanoparticles have been shown to be an effective catalyst in the synthesis of quinoxaline.

关键词： Fe3O4 nanocrystal solvothermal synthesis anisotropic growth twin plane

A biomass burning record from the Lingtai Loess Section during the last 370 ka and implication for climate and environment

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Chinese Science Bulletin 2006年第17期51卷 2116-2124页

作者： ZHOU Bin SHEN Chengde sun yanmin YANG Ying YI Weixi Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China Institute of Earth Environment Chinese Academy of Sciences Xi'an710054 China

The history of natural fire and its rela- tionship with climate and vegetation are revealed from the content of elemental carbon and associated pollen data and paleoclimatic substitutive indicators for the loess of Lingtai Section in the last 370 ka BP. The study indicates that intense episodes of vegeta- tion fires occurred during the interim especially when the climate was changing from wet to drought. The average content of elemental carbon in the intergla- ciers is higher than that in the glaciers, which coin- cides with the biomass change locally (or globally). The content of elemental carbon increases in the stage around 130 ka BP, indicating that the vegeta- tion and climate pattern have changed, which may contribute to the variation of CO2. As a whole, the content of elemental carbon increasing with the time reflects the increasing aridity trend to some degree. In addition, the occurrence of the maximum peak and the highest average content of elemental carbon in the Holocene reflects the occurrence of a rapid cli- mate event in 5900 a BP and more frequent fires caused by anthropic activities.

关键词：碳元素生物量环境气候

Vegetation evolution on the central Chinese Loess Plateau since late Quaternary evidenced by elemental carbon isotopic composition

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Chinese Science Bulletin 2009年第12期54卷 2082-2089页

作者： ZHOU Bin SHEN ChengDe ZHENG HongBo ZHAO MeiXun sun yanmin School of Earth Science and Engineering Nanjing University Nanjing 210093 China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China School of Ocean and Earth Science Tongji University Shanghai 200092 China Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China Qingdao 266100China

There are many controversial issues in loess studies such as natural vegetation types on the Chinese Loess Plateau during the historical periods and the spatial and temporal evolution of C3/C4 plants. Elemental carbon isotopic composition (δ13Cec) in the loess section may offer new evidence for these problems. Elemental carbon (EC) is produced by incomplete combustion of vegetation, and its carbon isotopic composition has a very small difference from that of the formal vegetation, then δ13Cec can be used as a record to recover the changes of vegetation. Elemental carbon was extracted by applying the oxidation method from the loess-paleosol sequence in the central Chinese Loess Plateau, and its carbon isotope composition was analyzed by the isotope mass spectrometer. The results showed that the vegetation in this region was a mixed type of C3 and C4 plants, dominated with C3 plants in most of the time. Since late Quaternary, C3/C4 plants may not follow a simple glacial-interglacial cycle mode on the Chinese Loess Plateau, but showing fluctuations. C3 plants increased gradually in L4 period, and more C3 plants occurred during S3 period, and C4 plants increased again during L3―L2 periods, after that, C3 plants dominated again during S1―S0 periods. During periods of paleosol development, C3 plants were abundant in S3 and S1, and there were more C4 plants in S2 and S0. During periods of loess sedimen- tation, there were more C3 plants in L4 and L1, and there were more C4 plants in L3 and L2. On the or- bital timescale, the vegetation variations revealed by δ13Cec record are consistent with the results of pollen data and also similar to the results obtained by organic carbon isotopic composition since the last glacial period.

关键词：碳同位素组成黄土高原植被演变晚第四纪元素碳 C4植物 C3植物证明

The elemental carbon record in Weinan loess section since the last 21 ka

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Chinese Science Bulletin 2001年第18期46卷 1541-1544页

作者： YANG Ying SHEN Chengde YI Weixi sun yanmin LIU Dongsheng Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China Xi’an State Key Laboratory of Loess and Quaternary Geology Chinese Academy of SciencesXi’an 710061China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029China

We studied the records of elemental carbon (EC) of the last 21 ka in the Weinan loess section, Shanxi Province. The variations of EC abundance and δ13CEC value along with depth (or age) were presented. There are four large peaks of EC abundance around the following years: 20.16 ka, 17.76 ka, 11.97 ka and 4.49 ka. Climatic situation was changed rapidly during these periods. The peaks around 11.97 ka and 20.16 ka are particularly sharp, occurring over intervals of tens to hundreds of years, which could represent short-duration intense events. δ13CEc values in the upper 4 m of the Weinan loess section vary between -11.71‰ and -21.34‰, which suggests that the vegetation pattern of the last 21 ka on the Loess Plateau is G4-dominated grasses.

关键词： elemental carbon fire history Weinan loess section δ13C paleoenvironment.

Preparation of γ-Al2O3 via Hydrothermal Synthesis Using ρ-Al2O3 as Raw Material for Propane Dehydrogenation

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Transactions of Tianjin University 2020年第5期26卷 362-372页

作者： Hongguang Liu Xiaomin Dong Jiping Xia Xiaoyun Li yanmin sun Qi Cai School of Chemical Engineering and Technology Hebei University of TechnologyTianjin 300132China CNOOC Tianjin Chemical Research and Design Institute Co. LtdTianjin 300131China

γ-Al2O3 was prepared by hydrothermal synthesis usingρ-Al2O3 and urea as raw *** this work,the eff ects of the molar ratio of CO(NH2)2/Al and reaction temperature were investigated,and a Pt–Sn–K/γ-Al2O3 catalyst was *** ammonium aluminum carbonate hydroxide(AACH),γ-Al2O3,and Pt–Sn–K/γ-Al2O3 were characterized by X-ray diff raction,scanning electron microscopy,transmission electron microscopy,N2 adsorption–desorption,thermogravimetry–differential thermal analysis,and NH3 temperature-programmed desorption *** reactivity of Pt–Sn–K/γ-Al2O3 for propane dehydrogenation was tested in a micro-fixed-bed *** results show thatγ-Al2O3 with a specific surface area of 358.1 m 2/g and pore volume of 0.96 cm 3/g was obtained when the molar ratio of CO(NH2)2/Al was 3:1 and the reaction temperature was 140℃.The alumina obtained by calcination of AACH has a higher specific surface area and larger pore volume than the industrial pseudo-boehmite *** catalyst prepared from AACH as precursor showed high selectivity and conversion,which can reach 96.1%and 37.6%,respectively,for propane dehydrogenation.

关键词： Ammonium aluminum carbonate hydroxide γ-Al2O3 Catalyst Propane dehydrogenation

MXenes基纳米材料在水处理脱盐领域研究进展

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工业水处理 2024年第5期44卷 64-70页

作者：严硕南军李晓云卢雁飞王庆波孙彦民周永敏中海油天津化工研究设计院有限公司天津300131 中海油惠州石化有限公司广东惠州516267

二维材料中,MXenes材料由于具有超薄结构、良好的导电性、表面功能可调性、优异的光热转化等特性而受到广泛欢迎。使用MXenes材料对一系列脱盐材料进行改进,使其在脱盐领域得到了广泛应用。综述了MXenes材料脱盐策略的最新发展,介绍了MX... 详细信息

二维材料中,MXenes材料由于具有超薄结构、良好的导电性、表面功能可调性、优异的光热转化等特性而受到广泛欢迎。使用MXenes材料对一系列脱盐材料进行改进,使其在脱盐领域得到了广泛应用。综述了MXenes材料脱盐策略的最新发展,介绍了MXenes材料在电容去离子、太阳能界面蒸发、渗透气化脱盐等领域中的应用和发展。MXenes材料具有优异的脱盐能力,可以为当前日益严峻的淡水危机提供解决途径。

关键词： MXenes 脱盐电容去离子太阳能界面蒸发渗透气化