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Organo-Petrographic and Pore Facets of Permian Shale Beds of Jharia Basin with Implications to Shale Gas Reservoir

Journal of Earth Science 2017年第5期28卷 897-916页

作者： Vinod Atmaram Mendhe Subhashree Mishra Ranjit G.Khangar Alka Damodhar Kamble Durgesh kumar Atul kumar Varma H.Singh Sujeet kumar Mollika Bannerjee CSIR-Central Institute of Mining and Fuel Research GSI-Geological Survey of India Central Region iiT (ISM)-Department of Chemical Engineering Indian Institute of Technology (ISM) iiT (ISM)-Department of Applied Geology Indian Institute of Technology (ISM)

The shale deposits of Damodar Valley have received great attention since preliminary studies indicate their potential for shale gas. However, fundamental information allied to shale gas re- servoir characteristics are still rare in India, as exploration is in the primary stage. In this study, Ba- rakar shale beds of eastern part of Jharia Basin are evaluated for gas reservoir characteristics. It is evident that Barakar shales are carbonaceous, silty, contains sub-angular flecks of quartz and mica, irregular hair-line fractures and showing lithological variations along the bedding planes, signifying terrestrial-fluviatile deposits under reducing environment. The values of TOC varies from 1.21 wt.% to 17.32 wt.%, indicating good source rock potentiality. The vitrinite, liptinite, inertinite and mineral matter ranging from 0.28 vol.% to 12.98 vol.%, 0.17 vol.% to 3.23 vol.%, 0.23 vol.% to 9.05 vol.%, and 74.74 vol.% to 99.10 vol.%, respectively. The ternary facies plot of maceral composition substan- tiated that Barakar shales are vitrinite rich and placed in the thermal-dry gas prone region. The low values of the surface area determined following different methods point towards low methane storage capacity, this is because of diagenesis and alterations of potash feldspar responsible for pore blocking effect. The pore size distribution signifying the micro to mesoporous nature, while Type ii sorption curve with the H2 type of hysteresis pattern, specifies the heterogeneity in pore structure mainly combined-slit and bottle neck pores.

关键词： shale gas petrographic composition surface area pore disposition pore volume.

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Multi-length scale modeling of carburization,martensitic microstructure evolution and fatigue properties of steel gears

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Journal of Materials Science & Technology 2020年第14期47卷 157-165页

作者： Edward Charles Henry Crawford O’Brien Hemantha kumar Yeddu School of Engineering Newcastle UniversityNewcastle upon TyneNE17RUUnited Kingdom

Multi-length scale modeling is performed to(i)predict the carburized case depth of SAE8620 steel gears by solving the Fick’s second law of diffusion,(ii)model the martensitic microstructure evolution in a grain inside the carburized case as well as to study the effect of stress cycling on retained austenite(RA)and martensite using a 3D phase-field model,(iii)simulate the effect of carburization and different RA contents on macroscale fatigue behavior of SAE8620 steel spur gear using the finite element *** diffusion model predicts that the case depth increases with increasing heat treatment time and *** phase-field simulations show that RA can transform to martensite during fatigue loading,where the extent of the transformation will depend on the type of stresses applied,*** in a high stress regime or low stress regime of fatigue *** transformation of martensite to austenite is also observed in low RA sample under high stress *** macroscale simulations show that the carburized case with high RA gives rise to better fatigue life compared to that with low RA.

关键词： Phase-field model Martensitic transformation Microstructure Gear steel Carburization

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Individual variation in ballooning dispersal by black widow spiderlings： The effects of family and social rearing

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Current Zoology 2015年第3期61卷 520-528页

作者： J. Chadwick JOHNSON Rebecca HALPIN Dale STEVENS ii Annika VANNAN Jesse LAM Katie BRATSCH School of Mathematical and Natural Sciences (2352) Arizona State University at the West Campus Glendale AZ 85306 USA

Individual behavioral variation is ubiquitous across taxa and important to understand if we wish to fully use beha- vioral data to understand the ecology and evolution of organisms. Only recently have studies of individual variation in dispersal behavior become a focus of research. A better understanding of individual variation in dispersal behavior is likely to improve our understanding of population dynamics. In particular, the dynamics of critically small populations （endangered species） and large populations （pest species） may be driven by unique dispersal variants. Here we documented individual variation in the ballooning dispersal behavior of Western black widow spiderlings Latrodectus hesperus, an urban pest species found in superabundant in- festations throughout cities of the desert Southwest USA. We found a great deal of family-level variation in ballooning dispersal, and this variation was highly consistent （repeatable） across time. Maternal egg investment was a poor predictor of this ballooning dispersal. Instead, we show that spiderlings reared in isolation are significantly slower to disperse than spiderlings raised in a more natural setting surrounded by full siblings. Thus, our study examines a widespread but poorly understood dispersal behavior （ballooning）, and suggests urban pest population dynamics are likely driven by the interaction of variation in individuals, families and social environments

关键词： Individual variation Dispersal Spiders Ballooning Social rearing

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Thermodynamic analysis of metal segregation in dual phase high entropy ceramics

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Journal of Materiomics 2024年第4期10卷 889-895页

作者： Steven M.Smith ii William G.Fahrenholtz Gregory E.Hilmas Stefano Curtarolo Missouri University of Science and Technology Materials Science and Engineering DepartmentRollaMO65409USA Duke University Department of Mechanical Engineering and Materials ScienceDurhamNC27708USA Duke University Center of Autonomous Materials DesignDurhamNC27708USA

Equilibrium Gibbs'free energy calculations were used to determine metal segregation trends between boride and carbide solid solutions containing two metals that are relevant to dual phase high entropy *** model predicted that Ti had the strongest tendency to segregate to the boride phase followed by Zr,Nb,Mo,V,Hf,and Ta,which matches experimental results of measured *** ratio of a metal in the carbide phase to the content of the same metal in the corresponding metal boride had a linear trend with the change in standard Gibbs'free energy of reaction for a metal carbide reacting with B_(4)C to produce its corresponding metal boride and *** proposed model was used to predict the changes in standard Gibbs'free energy for CrC→CrB_(2) to be−260 kJ and WC→WB_(2) to be 148 kJ,which indicates that Cr has the strongest segregation to the boride and W has the strongest segregation to the *** proposed model can be used to estimate the segregation of metals in dual phase high entropy boride-carbide ceramics of any boride/carbide ratio or metal content.

关键词： Dual phase High entropy ceramic Boride Carbide Thermodynamics

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Geochemistry and geochronology of A-type basement granitoids in the north-central Aravalli Craton: Implications on Paleoproterozoic geodynamics of NW Indian Block

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Geoscience Frontiers 2021年第4期12卷 138-150页

作者： Manoj K.Pandit Hitesh kumar WeiWang Department of Geology University of RajasthanJaipur 302004India Department of Mines and Geology Government of RajasthanJaipurRajasthanIndia State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and ResourcesChina University of GeosciencesWuhan 430074China

The basement granite gneisses from the north-central Aravalli Craton in NW India were investigated for geochemistry and *** a peneplain terrain,the granite gneiss outcrops are scanty and samples were collected mainly from two small hills and several ground-level exposures in the Sakhun–Ladera *** granite gneiss is the dominant lithology that also hosts dark,lenticular enclaves,and is in turn,intruded by mafic *** granite gneiss has silica content ranging from 61.37 wt.%to 68.27 wt.%that marks a slight overlap with the enclaves(54.32wt.%to 62.17wt.%).Both groups have a highK2O/Na2O(~2 or higher)***,the granite gneiss classify as granite–granodiorite,and enclaves as *** In-situ LA-ICP-MS zircon U–Pb geochronology of granite gneiss has yielded a statistically valid 1721±9 Ma age that we interpret as the emplacement age for the granitic *** characteristics of granite gneiss underline fractional crystallization of an I-type melt as themain process,and continuity of trends in enclaves underlines their mutual genetic *** genetic association is further verified by a consistency in the trace element characteristics and REE *** Nd-isotope signatures define a single grouping for both granite gneiss and enclaves,withεNd(t)values ranging from−6.38 to−6.61,further substantiating a common *** geochemical tectonic discrimination schemes consistently point toward an extensional setting and A-type characteristics for granite gneiss and *** are analogous to the coeval(1.72–1.75 Ga),A-type granitoids from the Khetri and Alwar basin in the North Delhi Fold Belt,implying a much larger areal extent for the Paleoproterozoic anorogenic magmatism in the northern segment of the Aravalli *** Paleoproterozoic age for the presumed‘Archean’basement in this region offers tacit evidence that the BGC–ii is a stratigraphically younger terrane as compared to the Archean age,

关键词： Basement granite Geochemistry Zircon U–Pb geochronology A-type granites Aravalli Craton NWIndian Block

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Aquaphotomics determination of nutrient biomarker for spectrophotometric parameterization of crop growth primary macronutrients using genetic programming

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Information Processing in Agriculture 2022年第4期9卷 497-513页

作者： Ronnie Concepcion ii Sandy Lauguico Jonnel Alejandrino Elmer Dadios Edwin Sybingco Argel Bandala Department of Manufacturing Engineering and Management De La Salle UniversityManila 1004Philippines Department of Electronics and Computer Engineering De La Salle UniversityManila 1004Philippines Center for Engineering and Sustainable Development Research De La Salle UniversityManila 1004Philippines

Water quality assessment is currently based on time-consuming and costly laboratory pro-cedures and numerous expensive physicochemical sensors *** response to the trend of device minimization and reduced outlays in sustainable aquaponic water monitoring,the integration of aquaphotomics and computational intelligence is presented in this *** study used the combination of temperature,pH,and electrical conductivity sensors in predicting crop growth primary macronutrient concentration(nitrate,phos-phate,and potassium(NPK)),thus,limiting the number of deployed sensors.A total of 220 water samples collected from an outdoor artificial aquaponic pond were temperature perturbed from 16 to 36℃ with 2℃ increments to mimic ambient range,which varies water compositional *** was applied on ultraviolet,visible light,and near-infrared spectral regions,100 to 1000 nm,to determine NPK ***-pal component analysis emphasized nutrient dynamics through selecting the highly corre-lated water absorption bands resulting in 250 nm,840 nm,and 765 nm for nitrate,phosphate,and potassium *** activated water bands were used as wave-length protocols to spectrophotometrically measure macronutrient ***-iments have shown that multigene symbolic regression genetic programming(MSRGP)obtained the optimal performance in parameterizing and predicting nitrate,phosphate,and potassium concentrations based on water physical properties with an accuracy of 87.63%,88.73%,and 99.91%,*** results have shown the established 4-dimensional nutrient dynamics map reveals that temperature significantly strengthens nitrate and potassium above 30℃ and phosphate below 25℃ with pH and electrical con-ductivity ranging between 7 and 8 and 0.1 to 0.2 mS cm^(-1) *** novel approach of developing a physicochemical estimation model predicted macronutrient concentra-tions in real-time using physical limnological sensors with a

关键词： Aquaphotomics Genetic programming Plant nutrients Physicochemical composition Spectrophotometry Water quality monitoring

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Strengthening mechanisms analysis and tailoring of bimodal grain structures for enhanced strength in CoCrFeMnNi high-entropy alloys

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Rare Metals 2024年第8期43卷 3893-3903页

作者： Jaesoung Lee Seulgi Kim Taehyun Kwon Young ii Kim Suyeon Kim Sung Ho Song Bin Lee Dongju Lee Department of Urban Energyand Environmental EngineeringChungbuk National UniversityCheongju 28644Republic of Korea Division of Advanced Materials Engineering Kongju National UniversityChungnam 330-717Republic of Korea Department of Advanced Materials Engineering for Information and Electronics Integrated-Education Institute for Frontier Science and Technology(BK21 Four)Kyung Hee UniversityYongin17104Republic of Korea

The CoCrFeMnNi high-entropy alloys(HEAs)with a(face-centered cubic) FCC structure has garnered considerable attention for its exceptional ductility and strain hardening ***,its yield strength is insufficient for structural *** this study,strengthening mechanisms in these HEAs were investigated to gain insight into the mechanical properties according to alloy powder ***,we present a novel approach to achieve both high strength and high ductility through the creation of a bimodal structure consisting of both coarse and fine grains via gas atomization and spark plasma sintering processes.A bimodally structured HEA prepared with a mass ratio of 2:8 between coarse particles(75-106 μm) and fine particles(≤25 μm)yielded optimal results,with a strength of 491.95 MPa and elongation of 19.64%.This strength value represents an~41% increase compared with the sample that displayed a fine single microstructure(347.08 MPa for yield strength).The strength enhancement was attributed to the prevention of plastic deformation initiation from the fine particles during *** innovative approach to the creation of HEAs with bimodal structures shows promise for various applications,such as structural components that require a combination of high strength and high ductility.

关键词： High-entropy alloys CrCoFeMoNi Bimodal Gas atomization Mechanical properties

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Multiple mechanisms in woodland plant species invasion

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Journal of Plant Ecology 2019年第2期12卷 201-209页

作者： Robert J.Warren ii Matt Candeias Adam Labatore Michael Olejniczak Lin Yang Department of Biology SUNY Buffalo State1300 Elmwood AvenueBuffaloNY 14222USA Department of Natural Resources University of IllinoisW-503 Turner Hall 1102 South Goodwin AveUrbanaIL 61801USA US Army Corps of Engineers 441 G Street NWWashingtonDC 20314-1000USA

Aims A plethora of theories explain species invasion,yet when tested in isolation,support or falsification becomes contingent on study species,system and *** objective was to examine com-munity-level species invasion as a function of multiple competing *** We used data from>3500 woodland plant species in 2750 plots in 49 national parks in eastern US deciduous forests to test multiple competing theories of species invasion:competition,empty niche,propagule pressure and latitude *** also tested interac-tions with residence time to account for non-native species naturali-zation and spread since *** Findings The non-native herbs generally thrived at latitudes similar to those from which they originated,but not necessarily where they were originally introduced to the eastern ***,we found that each hypothesis explained at least some aspect of woodland plant species invasion,but examining them simultaneously allowed assessment of their relative strengths and *** results suggested that residence time is a strong predictor of non-native woodland plant success,particularly as it interacts with other mechanisms of inva-sion,such as competition(abundance of native woodland plants),climate matching(similar invaded latitude as home range),prop-agule pressure(distance to putative seed sources)and empty niche(relatedness to native plants).We found that initial barriers,such as distance from propagule source or suboptimal habitat,were over-come,as was resistance from native ***,the biggest challenge for the non-native woodland plants appeared to be time,as they declined after~1 to 2 centuries.

关键词： competition empty niche invasion biology propagule pressure latitude matching residence time

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中国五加科植物的分类学研究:罗伞属和鹅掌柴属的新种和新异名(英文)

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植物分类学报 2006年第6期44卷 641-648页

作者： Porter P. LOWRY ii 向其柏 Missouri Botanical Garden P.O.Box 299St.LouisMO63166-0299U.S.A.Département Systématique et Evolution(UMS 602)Muséum Nationald’Histoire NaturelleCP 3957 rue Cuvier75231 Paris CEDEX 05France 南京林业大学森林资源与环境学院

在编写《FloraofChina》五加科Araliaceae时,发现两个新种,即拟榕叶罗伞BrassaiopsispseudoficifoliaLowry&***和光华鹅掌柴SchefflerazhuanaLowry&***。前者与榕叶罗伞***很相似,其区别在于,叶裂片数目较多,花序上具较多的伞形花序,花序轴具刺,主要分布于云南,广西偶见。后者与白花鹅掌柴***.相似,其区别在于,子房心皮数目较多,果时具明显的萼缘,花盘扁平,叶质地较薄,局限分布于西藏墨脱县。同时发现越南产的BrassaiopsisgausseniiBui和中国产的细序鹅掌柴***、球序鹅掌柴***均不能成立,处理为异名。

关键词：罗伞属鹅掌柴属拟榕叶罗伞光华鹅掌柴五加科新种新异名中国

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Composition Operators on Dirichlet Spaces and Bloch Space

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Acta Mathematica Sinica,English Series 2014年第10期30卷 1775-1784页

作者： Yuan CHENG Sanjay kumar Ze Hua ZHOU Institute of Mathematics School of Science Tianjin University of Technology and Education Department of Mathematics University of Jammu Department of Mathematics Tianjin University Center for Applied Mathematics of Tianjin University

In this paper we give a Carleson measure characterization for the compact composition operators between Dirichlet type spaces. We use this characterization to show that every compact composition operator on Dirichlet ... 详细信息

关键词： Bergman spaces Bloch space Carleson measure composition operators Dirichlet typespaces

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