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Chinese Journal Of Geochemistry 2015年第3期34卷 447-458页

作者： J.Madhavaraju A.N.Sial S.M.Hussain R.Nagarajan S.Ramasamy Estación Regional del Noroeste Instituto de GeologíaUniversidad Nacional Autónoma de México Nucleo de Estudos Geoquímicos e Laborató rio de Isótopos Estáveis (neg - labise) Departmento de GeologiaUniversidade Federal de Pernambuco Department of Geology University of Madras Department of Applied Geology School of Engineering and Science Curtin University

Petrography, carbon and oxygen isotopic study was carried out to interpret isotopic variations on the predominant carbonate sequence of the Dalmiapuram Formation of the Cauvery Basin, South India. The common petrographic types identified in the Dalmiapuram Formation range from wackestone to boundstone. The gray shale and limestone members show large variations in d13 C and d18 O values(Gray shale member: +1.44 to +2.40 %VPDB,-3.05 to-5.92 % VPDB, respectively; Limestone member:-6.07 to +2.93 % VPDB;-7.08 to-0.39 %VPDB; respectively). In the present study, the carbon and oxygen values are not correlated, which supports the fact that these limestones retain their primary isotopic signatures. In carbon isotope curve, one negative shift is identified in the gray shale member and a positive isotopic excursion is detected in the coral algal limestone(CAL).The observed positive isotopic excursion in the lower part of the CAL correlates with OAE1 d and suggests the global nature of the late Albian OAE1 d in the Cauvery Basin.

关键词：稳定同位素岩相学盆地印度蕴涵碳酸盐岩氧同位素偏移检测

Sedimentary Organic Matter Characterization on a Tropical Continental Shelf in Northeastern Brazil

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International Journal of Geosciences 2020年第6期11卷 393-419页

作者： Roberto Lima Barcellos Maria Cristina da Silva Sales de Melo Alcides Nobrega Sial Valdir do Amaral Vaz Manso Labogeo/GSGMar Oceanography Department Federal University of Pernambuco Recife Brazil LGGM Geology Department Federal University of Pernambuco Recife Brazil neg-labise Geology Department Federal University of Pernambuco Recife Brazil

In continental shelf areas works where the focus is Geochemistry are widely relevant, due to the vast complexity and uses of these relief features (social, environmental and economic). On the Brazilian Northeast tropical shelves, with emphasis on the Pernambuco Continental Shelf (PCS), the published studies are limited and have aimed at portions closer to the coastline. The objective of the present work is the description of the characteristics and origin of sedimentary organic matter (SOM) in the inner and middle Pernambuco shelf, defining and classifying the local geochemical sedimentary facies. The sampling stations (136) were collected in the study area, and the grain-size, contents of total organic matter (TOM), calcium carbonate (CaCO3) were analyzed. The samples were processed in an elemental analyzer coupled with a mass spectrometer after the elimination of calcium carbonate. The obtained data were the grain-size, TOM, CaCO3, elemental (C, N) and the stable isotopic ratios of δ13C e δ15N of SOM. Based on the measured values of carbon and nitrogen, the C/N ratio, associated to δ13C e δ15N, is observed that in the PCS predominates an organic matter of marine origin along its entire length: C < 1%, N < 1%, C/N < 5, <

关键词： Biogenic Sediments Total Nitrogen δ13C Stable Isotopic Ratio Geochemical Facies Pernambuco

A shift in redox conditions near the Ediacaran/Cambrian transition and its possible influence on early animal evolution,CorumbáGroup,Brazil

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Geoscience Frontiers 2024年第4期15卷 148-158页

作者： Fabricio A.Caxito Erik Sperling Gabriella Fazio Rodrigo Rodrigues Adorno Matheus Denezine Dermeval Aparecido Do Carmo Martino Giorgioni Gabriel J.Uhlein Alcides N.Sial CPMTC Research Center and Programa de Pós-graduação em Geologia Departamento de GeologiaInstituto de GeociênciasUniversidade Federal de Minas GeraisBelo HorizonteMG 31270-901Brazil Department of Earth and Planetary Sciences Doerr School of SustainabilityStanford UniversityCA 94305USA Instituto de Geociências Universidade de BrasíliaBrasíliaDF 70910-900Brazil Center for Applied Geosciences(CGA)of the Geological Survey of Brazil(SBG/CPRM) BrasíliaDistrito Federal 70040-904Brazil neg labise Universidade Federal de PernambucoRecife-PE 50740-530Brazil

The Ediacaran-Cambrian transition witnessed some of the most important biological,tectonic,climatic and geochemical changes in Earth's *** utmost importance for early animal evolution is the likely shift in redox conditions of bottom waters,which might have taken place in distinct pulses during the late Ediacaran and early *** track redox changes during this transition,we present new trace element,total organic carbon and both inorganic and organic carbon isotopes,and the first iron speciation data on the Tamengo and Guaicurus formations of the CorumbáGroup in western Brazil,which record important paleobiological changes between 555 Ma to<541 *** stratigraphically older Tamengo Formation is composed mainly of limestone with interbedded marls and mudrocks,and bears fragments of upper Ediacaran biomineralized fossils such as Cloudina lucianoi and Corumbella *** younger Guaicurus Formation represents a regional transgression of the shallow carbonate platform and is composed of a homogeneous fine-grained siliciclastic succession,bearing meiofaunal bilateral *** new iron speciation data reveal predominantly anoxic and ferruginous(non-sulfidic)bottom water conditions during deposition of the Tamengo Formation,with FeHR/FeT around 0.8 and FePy/FeHR below *** transition from the Tamengo to the Guaicurus Formation is marked by a stratigraphically rapid drop in FeHR/FeT to below 0.2,recording a shift to likely oxic bottom waters,which persist ***-sensitive element(RSE)concentrations are muted in both formations,but consistent with non-sulfidic bottom water conditions *** interpret the collected data to reflect a transition between two distinct paleoenvironmental *** Tamengo Formation represents an environment with anoxic bottom waters,with fragments of biomineralized organisms that lived on shallower,proba-bly mildly oxygenated surficial waters,and that were then transported *** to coeval suc

关键词： Atmospheric oxygenation Gondwana Redox proxies Iron speciation Ediacaran biota Redox-sensitive elements

SiGe工艺中HBT结构ESD保护电路设计

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半导体技术 2012年第8期37卷 653-657页

作者：王邦麟苏庆金峰李平梁徐向明上海华虹neg电子有限公司上海201206

为有效控制生产成本,减少工艺步骤,提出了在SiGe工艺中,用SiGe异质结双极型晶体管(HBT)代替传统二极管来实现静电放电(ESD)保护的方案。通过设计不同的HBT器件的版图结构,以及采取不同的端口连接方式,对HBT单体结构防护ESD的能力强弱和... 详细信息

为有效控制生产成本,减少工艺步骤,提出了在SiGe工艺中,用SiGe异质结双极型晶体管(HBT)代替传统二极管来实现静电放电(ESD)保护的方案。通过设计不同的HBT器件的版图结构,以及采取不同的端口连接方式,对HBT单体结构防护ESD的能力强弱和其寄生电容大小之间的关系进行了比较分析,并从中找出最优化的ESD解决方案。应用于实际电路中的验证结果表明,此方案在ESD防护能力达到人体模型(HBM)2 kV的基础上,I/O(IN/OUT输入输出)端口的寄生电容值可以做到200 fF以下,且此电容值还可通过HBT串联模式进一步降低。

关键词：异质结双极型晶体管锗硅静电保护寄生电容射频

Fourth South American Symposium on Isotope Geology （IV SSAGI）

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Episodes 2004年第2期27卷 132-133页

作者： AlcidesNobregaSial PierreSabaté ValderezPintoFerreira DepartmentofGeologyFederalUniversityofPernambucoC.P.7852 RecifePE50670-000BRAZIL InstitutdeRecherchepourleDéveloppement（IRD）Brasilia D.F.70000BRAZIL StableIsotopeLaboratory（labise）DepartmentofGeologyFederalUniversityofPernambucoC.P.7852.Recife PE50670-000BRAZIL

An increasing number of geologists in South America have turned their attention to isotope geology as a tool in the wider context of the Earth Sciences. As a result, a series of symposia on the South American isotope geology (SSAGI) has been organized every two years to provide an appropriate forum for discussion of methods and applications of stable and radiogenic isotopes.

关键词：同位素地质学放射性同位素巴西正式会议

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玻璃的成分和性质的模拟方法

硅酸盐学报 2022年第8期50卷 2338-2350页

作者：张丽艳李洪陈树彬李忠镝阮苠秩薛天锋钱敏凡思军中国科学院上海光学精密机械研究所强激光材料重点实验室上海201800 日本电气硝子株式会社(neg)美国分公司美国北卡罗来纳28150 中国核电工程有限公司北京100840

介绍了加和法、相图法、Priven法、拓扑束缚理论、分子动力学模拟、机器学习及数理统计模拟等7种玻璃成分性质模拟方法,总结了各模拟方法的主要理论依据、模拟过程及应用现状。加和法可进行多种玻璃物理性质的预测,相图法在二、三、四... 详细信息

介绍了加和法、相图法、Priven法、拓扑束缚理论、分子动力学模拟、机器学习及数理统计模拟等7种玻璃成分性质模拟方法,总结了各模拟方法的主要理论依据、模拟过程及应用现状。加和法可进行多种玻璃物理性质的预测,相图法在二、三、四元硅酸盐、硼酸盐及硼硅酸盐玻璃体系上的运用较为成熟,Priven法结合了玻璃结构、热力学方程及计算机模拟,拓扑束缚理论目前应用于氧化物和硫化物体系个别性质的模拟,分子动力学模拟亦应用于多种玻璃体系中的分子结构分析和相关性质预测,机器学习能充分利用文献中提供的大量数据来模拟复杂玻璃性质。目前数理统计模拟法已用在建立复杂玻璃体系中的成分(C)–结构(S)–性质(P)的相关数学模型,包括硅酸盐,硼硅酸盐和磷酸盐玻璃。较传统的C–P统计模拟方法,C–S–P统计模拟法能对复杂玻璃体系提供更精准的性质评估,有助于新型玻璃开发。

关键词：加和法相图法 Priven法拓扑束缚理论分子动力学模拟机器学习数理统计模拟

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模拟高放废液硼硅酸盐玻璃固化体钼分相与化学稳定性的结构基因模拟

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硅酸盐学报 2024年第6期52卷 2068-2080页

作者：戴晨李洪张丽艳胡丽丽朱小莉潘安练湖南大学材料科学与工程学院长沙410082中国中国科学院上海光学精密机械研究所高功率激光单元技术实验室上海201800中国日本电气硝子株式会社(neg)美国分公司北卡罗来纳28150美国

碱金属钼酸盐黄相在高放废液玻璃固化过程中难以处理,严重影响玻璃的化学稳定性。为了对高钼废液固化玻璃的化学稳定性进行较为准确的预判,从而加速配方研发进程,利用玻璃结构基因模拟法(GSg M)研究了高Mo (2.6%~3.3%,质量分数)模拟高... 详细信息

碱金属钼酸盐黄相在高放废液玻璃固化过程中难以处理,严重影响玻璃的化学稳定性。为了对高钼废液固化玻璃的化学稳定性进行较为准确的预判,从而加速配方研发进程,利用玻璃结构基因模拟法(GSg M)研究了高Mo (2.6%~3.3%,质量分数)模拟高放废液硼硅酸盐玻璃的化稳性和钼分相累积情况,建立了B、Li、Na、Mo浸出率、玻璃转变温度和钼分相累积程度的结构预测模型,并进行了模型验证。研究显示,在本工作的成分研究范围内,钼分相成分主要为CsLiMoO_(4)(水溶性黄相)及CaMoO_(4)(耐水性晶相)。成分–结构–性质关系表明,提高Li_(2)O和CaO会显著促进钼分相的形成。518~528 cm^(-1)Si—O—Si振动增强,则钼分相加剧,但[BO_(3)]基团中B—O—B振动增强,可有效减少钼分相的析出。模型验证结果表明,各性质的结构预测模型可对设计玻璃的化稳性及钼分相累积程度进行快速预测,以筛选设计玻璃配方是否有进一步研究的必要。

关键词：高放废液硼硅酸盐玻璃固化钼分相浸出率结构基因模拟

Investment in Generation of Photovoltaic Solar Energy: A Fezsibility Study with Flexibility and Uncertainty

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Energy and Power Engineering 2023年第7期15卷 241-263页

作者： Lucimeire Cordeiro da Silva Tara Keshar Nanda Baidya Programa de Pós-Graduaç &atildeo em Administra&ccedil&atildeo UNIGRANRIO Universidade Grande Rio Rio de Janeiro Brazil Escola de Gestã o e Negócios UNIFOA Centro Universitário de Volta Redonda Volta Redonda/RJ Brazil

The objective of this research will be to calculate the feasibility of investing in a solar energy generation project through the development of a methodology that allows the capture of environmental uncertainties by improving decision making. The article presents a comparative study of the feasibility analysis of investment in a solar mini solar energy for a Shopping, considering a regime of certainty and uncertainty. The assumed stochastic variables were energy tariff and price of solar panels. The trajectories were simulated with the binomial approach that combined resulted in a quadratic diagram. The applied methodology presented the best recommendation and the option to wait was the most valuable. The exchange of the energy obtained from LIGHT by own generation of energy with solar photovoltaic source will be viable for the manager since it observes the behavior of the variables over time and follows the rules of optimal decision.

关键词： Real Options Self-Generation Decision Making Solar Energy Feasibility of Investment

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风力涡轮机叶片

高科技纤维与应用 2006年第3期31卷 47-47页

本发明涉及风力涡轮机叶片，其包含许多预先预制的沿外部圆周顺序布置的条带。条带由纤维合成材料最好是碳纤维构成，也可以由木质材料最好是胶合板或固化树脂中的木质纤维构成。优点是，它使制造与传统制造技术相比具有优良硬度和高强... 详细信息

本发明涉及风力涡轮机叶片，其包含许多预先预制的沿外部圆周顺序布置的条带。条带由纤维合成材料最好是碳纤维构成，也可以由木质材料最好是胶合板或固化树脂中的木质纤维构成。优点是，它使制造与传统制造技术相比具有优良硬度和高强度但又易于制造且又非常便宜的用于风力涡轮机的叶片成为可能。本发明也涉及制造预先预制的条带的方法和制造风力涡轮机叶片的方法。

关键词：风力涡轮机叶片制造技术纤维合成材料木质纤维固化树脂木质材料条带碳纤维胶合板

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状态监测在风电机组齿轮箱上应用的探讨

风力发电 2002年第4期18卷 24-26,34页

作者：徐海峰吴昊等华北电力科学研究院有限责任公司，北京100045 北京neg－MICON国投风电设备公司，北京101300

状态监测不仅适用于风电机组齿轮箱，同时适用于风电机组的主轴，发电机和偏航系统轴承状态的监测，状态监测可以对风电机组进行故障诊断，还可以针对正在运行的风电机组，进行运转状态的全过程监测。

关键词：状态监测风电机组齿轮箱故障诊断