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Quantitat.ve analysis of melt and fluid inclusions by LA-ICP-Ms: Practical aspects and selected results

岩石学报 2000年第4期16卷 715-715页

作者： andreas audétat. 2000. department of geological sciences, virginia technology, blacksburg, va 24061, u.s.a. department of geological sciences Virginia Technology Blacksburg VA 24061 United States

Laser ablation ICP Ms is an extremely sensitive (yet destructive) analytical technique that allows major and trace elements to be quantified in fluid and melt inclusions as small as 10 μm. Individual inclusions are drilled out of their host mineral by using a laser beam (preferably 193 nm ArF Excimer laser), and the ablated material is continuously transported with an Ar/He gas mixture into the mass spectrometer (Günther and Heinrich, 1999). The resulting transient signals are integrated and compared with signals obtained from standard glasses. The LA ICP Ms system at ETH Zürich (switzerland) allows up to 30 major and trace elements to be measured simultaneously, with detection limits typically being in the order of 10-100 ppm for a medium salinity, 30 μm sized inclusion (Günther et al ., 1998; audétat.et al ., 2000.,b). Main source of analytical uncertainty is the process of internal standardization, for which the absolute concentration of one element has to be estimated by an independent method. In case of fluid inclusions this is done by calculating Na from the total salinity (NaCl equiv ), and correcting this value for other major cations present in solution. The internal standardization of melt inclusions is based on Al, which is determined either by microprobe analysis of re homogenized inclusions, or is estimated from LA ICP Ms elemental ratios in conjunction with whole rock geochemical data. Examples of applications include: (i) geochemical evolution of hydrothermal fluids in ore deposits, (ii) metal fractionation between vapor and brine, and (iii) element partitioning between melt and aqueous fluid(s). LA ICP Ms analysis of successive generations of fluid inclusions in quartz crystals from the sn/W mineralized Mole Granite (Australia) demonstrates that ore precipitat.on was triggered by dilution of the magmatic fluid with meteoric water (audétat.et al ., 1998, 2000.). Partition coefficients determined on pairs of clearly cogenetic vapor and brine inclusions

关键词： ICP Practical aspects and selected results Quantitat.ve analysis of melt and fluid inclusions by LA-ICP-Ms

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Determination of internal pressure of synthetic fluid inclusions in the H2O-CH4 system using Raman spectroscopy

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岩石学报 2000年第4期16卷 717-717页

作者： Jing Leng. 2000. department of geological sciences, virginia technology, blacksburg, va 24061, u.s.a. department of geological sciences Virginia Technology Blacksburg VA 24061 United States

Raman spectroscopy is widely used in chemical, physical, biological and geological sciences, where it is used for both qualitat.ve and quantitat.ve studies. Because each scattering molecular species has its own characteristic Raman spectrum, the method often is used to simply identify a chemical species. The intensity of the peaks can be used to measure the concentration of the scattering species. Changes in wave number (vibrational frequency or peak position) may be used to study the effects of density, temperature and pressure on a chemical species. When the environment (such as the temperature and pressure) of the system changes, the spatial configuration of atoms is affected by slight adjustments in the covalent bonds. As a result the vibrational frequency and the wavenumber of the Raman spectrum are shifted. By heating or cooling the inclusions, the internal pressure of the inclusions vary accordingly with temperature since the inclusions represent a constant volume system. The objective of the current research is to document the effect of the pressure and temperature on the measured spectral parameters of a given species in a fluid inclusion, and thereby to generate a data set that can be used to measure the total pressure within a fluid inclusion at any given temperature.\;The reported experiments here were conducted using a DILOR XY molar laser Raman microprobe on three synthetic CH 4 H 2O fluid inclusions containing 6565ppm, 17192ppm and 49189ppm CH 4. The excitat.on energy was provided by a 514 nm Ar + laser using a power setting of 100 mW. The spectrometer gratings were set at 1200 grooves/mm resulting in a resolution of ±3cm -1 . An analysis time of 300 seconds was selected to maximize the signal to noise ratio. The slit width was 100 μm. The Raman peak position of methane was measured at different temperatures from 25°C to the final homogenisation temperature of the inclusion at an increment of 25°C degree using a Chaixmeca heating stage attached to the

关键词： Determination of internal pressure of synthetic fluid inclusions in the H2O-CH4 system using Raman spectroscopy CH

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Local MFs Matrix Decomposition Algorithms for Elliptic BVPs in Annuli

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Numerical Mathematics(Theory,Methods and Applications) 2024年第1期17卷 93-120页

作者： C.s.Chen andreas Karageorghis Min Lei school of Mathematics and Natural sciences University of Southern MississippiHattiesburgMS 39406USA department of Mathematics and stat.stics University of CyprusP.O.Box 20537Nicosia 1678Cyprus College of Mathematics Taiyuan University of TechnologyTaiyuan 030024P.R.China

We apply the local method of fundamental solutions(LMFs)to boundary value problems(BVPs)for the Laplace and homogeneous biharmonic equations in *** appropriately choosing the collocation points,the LMFs discretization yields sparse block circulant system *** a result,matrix decomposition algorithms(MDAs)and fast Fourier transforms(FFTs)can be used for the solution of the systems resulting in considerable savings in both computat.onal time and storage *** accuracy of the method and its ability to solve large scale problems are demonstrated by applying it to several numerical experiments.

关键词： Local method of fundamental solutions Poisson equation biharmonic equation matrix decomposition algorithms fast Fourier transforms

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Palaeomagnetic study on the Precambrian-Cambrian Boundary Candidate stratotype section at Meishucun, Yunnan

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Acta Geologica sinica(English Edition) 1991年第1期65卷 97-108页

作者： Liang Qizhong Fang Wu Rob van der Voo Yunnan Institute of geological science, Kunming,Yunnan department of geological sciences,university of Michigan,Ann Arbor, MI.48109-1063, u.s.a. Liu Linqun Yunnan Institute of geological scienc Kunming Yunnan China

The Meishucun secton has been recommended as an international candidate stratotype secton of thePrecambrian-Cambrian boundary. The paper deals with the palaeomagnetic study on the section. A total of159 palaeomagnetic samples were successively collected from the platform-facies sequence of carbonates andphosphates at the section. Thermal demagnetization results indicate a great majority of the rocks at the sectionhave been strongly overprinted by recent magnetic field, but 57 samples have preserved remanentmagnetization with antipodal directions (mean D/I=4.2°/ 7.1°, K=9, α_(95) = 6.6°). Baaed on calculation,the location of the palaeomagnetic pole was at 68.8°N and 270.7°E, which is different from any palaeopolesobtained from younger Phanerozoic rocks in south China. The results reveal a polarity zonation which in-cludes at least 9 reversal events. A comparison of China's magnetostratigraphic records with those fromsiberia, Australia and the western u.s.a. shows that all the sections are characterized by frequent polarity re-versals.

关键词： Yunnan Palaeomagnetic study on the Precambrian-Cambrian Boundary Candidate stratotype section at Meishucun

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Polymer transfer film formation from cryogenic to elevated temperatures

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Friction 2024年第9期12卷 2018-2032页

作者： Kian BAsHANDEH vasilis TsIGKIs Ahmad AMIRI Pixiang LAN andreas A.POLYCARPOu J.Mike Walker’66 department of Mechanical Engineering Texas A&M UniversityCollege StationTexas 77843USA ATsP Innovations Inc.HoustonTexas 77055USA Russell school of Chemical Engineering The University of TulsaTulsaOklahoma 74104USA department of Mechanical Engineering The University of TulsaTulsaOklahoma 74104USA

This study reports on the tribological performance of aromatic thermosetting co-polyester(ATsP)and polyether ether ketone(PEEK)-based polymer composite coatings mixed with PTFE *** coatings were tested across a wide temperature range from−180 to 110℃ to simulate the environmental temperatures on Titan,Moon,and Mars,which are of particular interest for NAsA’s future exploratory *** experimental setup was developed to conduct the pin-on-disk experiments under dry sliding conditions and extreme temperature and contact *** film formation and its characteristics were found to play significant roles in the tribological performance,and the characteristics of the film were *** XPs and sEM analysis indicated the increase of the PTFE content in the transfer film as the temperature decreased to cryogenic *** coefficient of friction did not follow a linear trend with temperature and was minimum at 110℃ and maximum at−180℃.ATsP coating showed superior performance with lower friction and unmeasurable wear at all temperatures,whereas PEEK coating exhibited maximum wear at 25℃ followed by−180,and 110℃.

关键词： transfer film cryogenic high temperature tribology space tribology polymer coating

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CO_2 Density-Raman shift Relation Derived from synthetic Inclusions in Fused silica Capillaries and Applications

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地学前缘 2009年第S1期16卷 165-166页

作者： Yucai song,I-Ming Chou,Wenxuan Hu 1.Institute of Geology,Chinese Academy of geological sciences,Beijing 100037,China. 2.u.s.geological survey,National Center,Reston va 20192,u.s.a. 3.department of Earth sciences,Nanjing university,Nanjing 210093,China

The density of CO2 inclusions in minerals is commonly used to determine the crystallizing conditions of the host ***,the conventional microthermometry method is difficult to apply for inclusions that are small in size... 详细信息

The density of COsub>2sub> inclusions in minerals is commonly used to determine the crystallizing conditions of the host ***,the conventional microthermometry method is difficult to apply for inclusions that are small in size（sis is an alternative method for determining COsub>2sub> density,provided that

关键词： synthetic fluid inclusion fused silica capillary CO2 inclusion CO2 density equation Raman analysis

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Distribution　of　heavy-metals　in　the　Grand　Canal(Hangzhou　section)and　its　contributing　factors

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Journal of Environmental sciences 1997年第3期9卷 12-24页

作者： Weng Huanxin, Zhang Dengrong department of Earth sciences, Zhejiang university, Hangzhou 310027, China Charlie Y.Xu department of geological sciences, university of Illinois at Chicago. u.s.a.

The Grand Canal (Hangzhou section), People's Republic of China, has been highly contaminated by heavy metals from both industrial and municipal sources since 1950s. This study investigated the distribution of heavy metals including As, Cr, Cd, Cu, Ni, Pb, and Zn. The results showed that these metals are largely accumulated in the top 0 3 meter layer of the river *** the contamination, heavy metal concentrations in solution are increased in some locations only. The only exception is Zn whose concentrations are extremely high both in solution and in the top layer sediment. The top layer sediment appears to have reached almost its sorption capacity with respect to aqueous Zn. The extent of contamination is in the sequence of Zn>Cu>Pb>As>Cd. It is speculated that Cu distribution has been significantly affected by its binding to organic matter in the top layer sediment. Based on Pb distribution in both water and sediment, it is suggested that Pb transport in the canal is associated with colloids or particles suspended in water. The study showed that the top layer sediment in the Grand Canal serves as a sink to anthropogenic contaminants consisting of heavy metals as well as organic compounds.

关键词： heavy metal distribution contributing factor the Grand Canal (Hangzhou section).

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Erratum to:Tribological behaviour of Ti_(3)C_(2)T_(x)nano-sheets:substrate-dependent tribo-chemical reactions

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Friction 2024年第7期12卷 1618-1619页

作者： Alberto ROTA Nicolas BELLINA Bo WANG andreas ROsENKRANZ Dipartimento di scienze Fisiche Informatiche e MatematicheUniversitàdi Modena e Reggio EmiliaModena 41125Italy CNR-Istituto di Nanoscienze Centro S3Modena 41125Italy Centro Interdipartimentale per la Ricerca Applicata e i servizi nel settore della Meccanica Avanzata e della Motoristica Universitàdi Modena e Reggio EmiliaModena 41125Italy Key Laboratory of Marine New Materials and Related technology Zhejiang Key Laboratory of Marine Materials and Protection TechnologyNingbo Institute of Material Technology&EngineeringChinese Academy of SciencesNingbo 315201China department of Chemical Engineering Biotechnology and MaterialsUniversity of ChileSantiago 8370456Chile

Erratum to Alberto Rota,Nicolas Bellina,Bo Wang&andreas *** behaviour of Ti_(3)C_(2)T_(x)nano-sheets:substratedependent tribo-chemical *** 11(8):1522–1533(2023).

关键词： Friction behaviour chemical

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A review of methane leakage from abandoned oil and gas wells:A case study in Lubbock,Texas,within the Permian Basin

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Energy Geoscience 2024年第3期5卷 1-12页

作者： stanley u.Opara Chinedu J.Okere Bob L.Herd department of Petroleum Engineering Texas Tech UniversityTXUSA

In the pursuit of global net zero carbon emissions and climate change mitigation,ongoing research into sustainable energy sources and emission control is *** review examines methane leakage from abandoned oil and gas(AOG)wells,focusing particularly on Lubbock,a geographic area situated within the larger region known as the Permian Basin in West Texas,united *** objective is to assess the extent and environmental implications of methane leakage from these *** analysis integrates pertinent literature,governmental and industry data,and prior Lubbock *** affecting methane leakage,including well integrity,geological characteristics,and human activities,are *** research estimates 1781 drilled wells in Lubbock,forming a foundation for targeted assessments and monitoring due to historical drilling *** hierarchy of well stat.ses in Lubbock highlights the prevalence of“active oil wells,”trailed by“plugged and abandoned oil wells”and“inactive oil wells.”Methane leakage potential aligns with these well types,underscoring the importance of strategic monitoring and *** analysis notes a zenith in“drilled and completed”wells during *** our study's case analysis and literature review reiterate the critical significance of assessing and mitigating methane emissions from AOG wells,it's important to clarify that the research does not directly provide methane leakage ***,it contextualizes the issue's magnitude and emphasizes the well type and stat.s analysis's role in targeted mitigation *** summary,our research deepens our understanding of methane leakage,aiding informed decision-making and policy formulation for environmental *** clarifying well type implications and historical drilling patterns,we aim to contribute to effective strategies in mitigating methane emissions from AOG wells.

关键词： Net zero carbon emissions Climate change mitigation Methane emission control Abandoned oil and gas(AOG)well Permian Basin

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MXene-Based Elastomer Mimetic stretchablesensors: Design, Properties, and Applications

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Nano-Micro Letters 2024年第7期16卷 295-342页

作者： Poushali Das Parham Khoshbakht Marvi sayan Ganguly Xiaowu(shirley)Tang Bo Wang seshasai srinivasan Amin Reza Rajabzadeh andreas Rosenkranz school of Biomedical Engineering McMaster University1280 Main Street WestHamiltonON L8S 4L8Canada department of Chemistry and Waterloo Institute for Nanotechnology(WIN) University of Waterloo200 University Ave WestWaterlooONCanada Centre for Eye and Vision Research(CEVR) 17W Hong Kong Science ParkShatinHong KongPeople’s Republic of China Chair of Functional Materials Department of Materials Science and EngineeringSaarland UniversitySaarbruckenGermany W Booth school of Engineering Practice and technology McMaster University1280 Main Street WestHamiltonON L8S 4L7Canada department for Chemical Engineering Biotechnology and MaterialsUniversity of ChileSantiagoChile

Flexible sensors based on MXene-polymer composites are highly prospective for next-generation wearable electronics used in human-machine *** of the motivating factors behind the progress of flexible sensors is the steady arrival of new conductive ***,a new family of 2D nanomaterials,have been draw-ing attention since the last decade due to their high electronic conduc-tivity,processability,mechanical robustness and chemical *** this review,we encompass the fabrication of MXene-based polymeric nanocomposites,their structure-property relationship,and applications in the flexible sensor ***,our discussion is not only lim-ited to sensor design,their mechanism,and various modes of sensing platform,but also their future perspective and market throughout the *** our article,we intend to fortify the bond between flexible matrices and MXenes thus promoting the swift advancement of flexible MXene-sensors for wearable technologies.

关键词： Flexible sensor 2D nanomaterials MXene Wearable and conductive Applications

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