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Geochemical evidences of trace metal anomalies for finding hydrocarbon microseepage in the petroliferous regions of the Tatipaka and Pasarlapudi areas of Krishna Godavari Basin,India

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Petroleum Science 2013年第1期10卷 19-29页

作者： Rasheed M A Lakshmi M Rao P L S Kalpana M S Dayal A M Patil D J Microbiology Laboratory Petroleum Geochemistry Group National Geophysical Research Institute (Council of Scientific and Industrial Research)

The long-term seepage of hydrocarbons, either as macroseepage or microseepage, can set up near-surface oxidation reduction zones that favor the development of a diverse array of chemical and mineralogical changes. The bacterial oxidation of light hydrocarbons can directly or indirectly bring about significant changes in the values of pH and Eh of the surrounding environment, thereby also changing the stability fields of the different mineral species present in that environment. The paper reports the role of hydrocarbon microseepage in surface alterations of trace metal concentrations. In this study trace metal alterations were mapped that appear to be associated with hydrocarbon microseepages in the oil/ gas fields. A total of 50 soil samples were collected near oil and gas fields of the Tatipaka and Pasarlapudi areas of the Krishna Godavari Basin, Andhra Pradesh. The soil samples were collected from a depth of 2-2.5 m. The paper reports the chemical alterations associated with trace metals in soils that are related to hydrocarbon microseepages above some of the major oil and gas fields of this petroliferous region. Trace metals, such as scandium （Sc）, vanadium （V）, chromium （Cr）, cobalt （Co）, nickel （Ni）, copper （Cu）, zinc （Zn）, barium （Ba） and strontium （Sr）, in soil samples were analyzed using inductively coupled plasma- mass spectrometry （ICP-MS）. The concentrations of Sc （8 to 40 mg/kg）, V （197 to 489 mg/kg）, Cr （106 to 287 mg/kg）, Co （31 to 52 mg/kg）, Ni （65 to 110 mg/kg）, Cu （88 to 131 mg/kg）, Zn （88 to 471 mg/kg）, Ba （263 to 3,091 mg/kg） and Sr （119 to 218 mg/kg） were obtained. It was observed that the concentrations of trace elements were tremendously increased when they were compared with their normal concentrations in soils. The analysis of adsorbed soil gas showed the presence of high concentrations of YC2＋（C2H6, C3H8 and n-C4H10） ranging from 7 to 222 μg/kg respectively. Integrated studies of trace elements over adsorbed light gaseous hydrocarbons （2C2

关键词： Hydrocarbons microseepage trace metal alterations adsorbed soil gas Krishna Godavari Basin

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Effects of Austenizing Temperature on Reprecipitation of BN

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Journal of Iron and Steel research International 2013年第9期20卷 99-104页

作者： YIN Shi-ke A Rong Mitsuru Tanino China Iron and Steel research Institute group Fundamental research Laboratory Nippon Steel Co.

Most of BN was precipitated around the spherical MnS and formed the compound of MnS and BN during the isothermal treatment at 850 ℃ after austenizing at 950-1050 ℃. Most of MnS was transformed into polygon when austenized at 1 150 ℃ or above, which could not be the nuclei of BN anymore. During the insulation process at 850 ℃, MnS kept the state of monomer. The compound of MnS and BN at earlier time was of fine polycrystalline in spherality and BN was formed as a plate-like monocrystal on a certain part of the polycrystalline when its dimension reached 0.6 μm.

关键词： austenizing temperature BN repreeipitation isothermal treatment

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Determination of the Insoluble Aluminum Content in Steel Samples by Using Laser-Induced Breakdown Spectroscopy

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Plasma Science and Technology 2015年第8期17卷 644-648页

作者：刘佳贾云海张勇孙念 Central Iron & Steel research Institute group

The insoluble aluminum content in steel samples has a significant influence on the quality of the steel. In this paper, laser-induced breakdown spectroscopy （LIBS） is used to analyze the insoluble aluminum content in steel samples using a scanning mode. The average intensity plus 2.5 standard deviations was iterated and the final iteration value was taken as the threshold that distinguishes soluble and insoluble aluminum, and thus total and soluble aluminum content calibration curves were generated. Using the relevant total and soluble aluminum content calibration curves, the total and soluble aluminum contents in steel samples could be determined. The insoluble aluminum content could be determined by subtracting the soluble aluminum content from the total aluminum content. The insoluble aluminum content of standard samples and process product samples were determined using the present mathematical model; the results agreed well with the certified reference values. This method could be used to rapidly characterize the insoluble aluminum content in steel samples.

关键词： laser-induced breakdown spectroscopy insoluble aluminum content thresholdintensity

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Microstructure and properties of aging Cu–Cr–Zr alloy

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Rare Metals 2014年第2期33卷 134-138页

作者： Kun Wang Ke-Fu Liu Jing-Bo Zhang Institute of Electric Lighting Source Fudan University No.23 research Institute China Electronics Technology Group Corporation No. 23 research Institute China Electronics Technology Group Corporation

The crystallography and morphology of precipitate particles in a Cu matrix were studied using an aged Cu–Cr–Zr alloy by transmission electron microscopy（TEM） and high-resolution transmission electron microscopy（HRTEM）. The tensile strength and electrical conductivity of this alloy after various aging processes were tested. The results show that two kinds of crystallographic structure associated with chromium-rich phases, fcc and bcc structure, exist in the peak-aging of the alloy. The orientation relationship between bcc Cr precipitate and the matrix exhibits Nishiyama–Wasserman orientation relationship. Two kinds of Zr-rich phases（Cu4Zr and Cu5Zr）can be identified and the habit plane is parallel to {111}Cu plane during the aging. The increase in strength is ascribed to the precipitation of Cr- and Zr-rich phase.

关键词： Cu–Cr–Zr alloy Aging process Crystallography Morphology Strengthening mechanism

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Completeness of citizen science biodiversity data from a volunteered geographic information perspective

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Geo-Spatial Information Science 2017年第1期20卷 3-13页

作者： Clemens Jacobs Alexander Zipf GIScience research group Institute of GeographyHeidelberg UniversityHeidelbergGermany

Observations of living organisms by citizen scientists that are reported to online portals are a valuable source of *** are also a special kind of volunteered geographic information(VGI).VGI data have issues of completeness,which arise from biases caused by the opportunistic nature of the data collection *** examined the completeness of bird species represented in citizen science observation data from eBird and iNaturalist in US National Parks(NPs).We used approaches for completeness estimation which were developed for data from OpenStreetMap,a crowdsourced map of the ***,we used an extrinsic approach,comparing species lists from citizen science data with National Park Service ***,we examined two intrinsic approaches using total observation numbers in NPs and the development of the number of new species being added to the data-set over *** from the extrinsic approach provided appropriate completeness estimations to evaluate the intrinsic *** found that total observation numbers are a good estimator of species completeness of citizen science data from US *** is also a close relationship between species completeness and the ratio of new species added to observation data *** numbers in a given year.

关键词： Citizen science Volunteered Geographic Information(VGI) data quality completeness

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Association between cag-pathogenicity island in Helicobacter pylori isolates from peptic ulcer,gastric carcinoma,and non-ulcer dyspepsia subjects with histological changes

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World Journal of Gastroenterology 2005年第43期11卷 6815-6822页

作者： Mahaboob Ali Aleem A Khan Santosh K Tiwari Niyaz Ahmed L Venkateswar Rao CM Habibullah Center for Liver research and Diagnostics Pathogen Evolution group Department of Microbiology

AIM： To investigate the presence of the cag-pathogenicity island and the associated histological damage caused by strains with complete cag-PAI and with partial deletions in correlation to the disease status. METHODS： We analyzed the complete cag-PAI of 174 representative Helicobacter pylori （H pylori ） clinical isolates obtained from patients with duodenal ulcer, gastric ulcer, gastric cancer, and non-ulcer dyspepsia using eight different oligonucleotide primers viz cagA1, cagA2, cagAP1, cagAP2, cagE, cagT, LEC-1, LEC-2 spanning five different loci of the whole cag-PAI by polymerase chain reaction （PCR）. RESULTS： The complete screening of the genes comprising the cag-PAI showed that larger proportions of subjects with gastric ulcer （97.8%） inhabited strains with complete cag-PAI, followed by gastric cancer （85.7%）, non-ulcer dyspepsia （7.1%）, and duodenal ulcer （6.9%）, significant differences were found in the percentage distribution of the genes in all the clinical groups studied. It was found that strains with complete cag-PAI were able to cause severe histological damage than with the partially deleted ones. CONCLUSION： The cag-PAI is a strong virulent marker in the disease pathogenesis as it is shown that a large number of those infected with strain with complete cag-PAI had one or the other of the irreversible gastric pathologies and interestingly 18.5% of them developed gastric carcinoma. The presence of an intact cag- PAI correlates with the development of more severe pathology, and such strains were found more frequently in patients with severe gastroduodenal disease. Partial deletions of the cag-PAI appear to be sufficient to render the organism less pathogenic.

关键词： Helicobacter pylori cag-pathogenicity island Genetic diversity Gastro-duodenal diseases

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The emergence and evolution of OpenStreetMap: a cellular automata approach

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International Journal of Digital Earth 2015年第1期8卷 76-90页

作者： Jamal Jokar Arsanjani Marco Helbich Mohamed Bakillah Lukas Loos GIScience research group Institute of GeographyHeidelberg UniversityHeidelbergGermany

Collaborative mapping projects,such as OpenStreetMap(OSM),have received tremendous amounts of contributed data from voluntary participants over *** far,most research efforts deal with data quality issues,but the OSM evolution across space and over time has not been ***,this study is dedicated to the evolution of the contributed information in order to understand an emergent phenomenon of so-called collaborative *** main objective of this paper is to monitor the evolutional pattern of OSM and predict potential future states through a cellular automata(CA)*** is exceedingly relevant for numerous OSM-based *** spatiotemporal analysis of the contributions for the time period 2007–2012,using the city of Heidelberg(Germany)as a case study,reveals that early contributions are given three years after the launching of OSM,while after nearly six years,most of the areas are *** simulation results for the validated CA model,predicting OSM states for 2014,provide clear evidence that most of the areas have been explored three years after people began mapping until 2010,and thereafter,the densification process has begun and will cover most parts of the city although the amount of contribution depends on the land use types.

关键词： cellular automata OpenStreetMap transition rules spatiotemporal analysis collaborative contributing

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Plasma-based CO_(2) conversion:How to correctly analyze the performance?

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Journal of Energy Chemistry 2023年第11期86卷 180-196,I0005页

作者： Bart Wanten Rani Vertongen Robin De Meyer Annemie Bogaerts research group PLASMANT Department of ChemistryUniversity of AntwerpUniversiteitsplein 12610 AntwerpBelgium research group EMAT Department of PhysicsUniversity of AntwerpGroenenborgerlaan 1712020 AntwerpBelgium

Plasma-based CO_(2)conversion is promising for carbon capture and ***,inconsistent reporting of the performance metrics makes it difficult to compare plasma processes systematically,complicates elucidating the underlying mechanisms and compromises further development of this ***,this critical review summarizes the correct definitions for gas conversion in plasma reactors and highlights common errors and inconsistencies observed throughout *** is done for pure CO_(2)splitting,dry reforming of methane and CO_(2)*** demonstrate that the change in volumetric flow rate is a critical aspect,inherent to these reactions,that is often not correctly taken into *** dry reforming of methane and CO_(2)hydrogenation,we also demonstrate inconsistent reporting of energy efficiency,and through numerical examples,we show the significance of these ***,we discuss how to measure changes in volumetric flow rate,supported by data from two experimental examples,showing that the sensitivity inherent to a standard component and a flow meter is essential to consider when deriving the performance ***,some general recommendations and good practices are *** paper aims to be a comprehensive guideline for authors,to encourage more consistent calculations and stimulate the further development of this technology.

关键词： Plasma CO_(2) Dry reforming of methane CO_(2) hydrogenation Conversion Performance

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A Compact Self-Isolated MIMO Antenna System for 5G Mobile Terminals

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Computer Systems Science & Engineering 2022年第9期42卷 919-934页

作者： Muhannad Y.Muhsin Ali J.Salim Jawad K.Ali Microwave research group Department of Electrical EngineeringUniversity of TechnologyBaghdad10001Iraq Microwave research group Department of Communication EngineeringUniversity of TechnologyBaghdad10001Iraq

A compact self-isolated Multi Input Multi Output (MIMO) antennaarray is presented for 5G mobile phone devices. The proposed antenna systemis operating at the 3.5 GHz band (3400–3600 MHz) and consists of eight antennaelements placed along two side edges of a mobile device, which meets the currenttrend requirements of full-screen smartphone devices. Each antenna element isdivided into two parts, a front part and back part. The front part consists of anI-shaped feeding line and a modified Hilbert fractal monopole antenna, whereasthe back part is an L-shaped element shorted to the system ground by a0.5 mm short stub. A desirable compactness can be obtained by utilizing the Hilbert space-filling property where the antenna element’s overall planar size printedon the side-edge frame is just (9.57 mm × 5.99 mm). The proposed MIMO antenna system has been simulated, analyzed, fabricated and tested. Based on the selfisolated property, good isolation (better than 15 dB) is attained without employingadditional decoupling elements and/or isolation techniques, which increases system complexity and reduces the antenna efficiency. The scattering parameters,antenna efficiencies, antenna gains, and antenna radiation characteristics areinvestigated to assess the proposed antenna performance. For evaluating the proposed antenna array system performance, the Envelope Correlation Coefficients(ECCs), Mean Effective Gains (MEGs) and channel capacity are *** antenna and MIMO performances are evaluated to confirm the suitability of the proposed MIMO antenna system for 5G mobile terminals.

关键词： 5G applications compact antennas isolation techniques MIMO antennas mobile terminals self-isolated antennas

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Micro and nano-enabled approaches to improve the performance of plasma electrolytic oxidation coated magnesium alloys

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Journal of Magnesium and Alloys 2021年第5期9卷 1497-1517页

作者： Safoora Farshid Mahshid Kharaziha Biomaterials research group Department of Materials EngineeringIsfahan University of TechnologyIsfahan***Iran

Magnesium(Mg)and its alloys have become a hot research topic in various industries owing to the specific physical and chemical ***,high corrosion rate is considered the key *** electrolytic oxidation(PEO)method is a simple strategy to deposit an oxide layer on the surface of light metals such as magnesium alloys,to control corrosion rate and promote some other properties,depending on their ***,their features including their micropore size,distribution,and interconnectivity,and microcracks have not been improved to an acceptable level to support long-term performances of the magnesium-based *** have introduced micro/nano-enabled approaches to enhance various properties of PEO coatings such as corrosion resistance,tribological properties,self-healing ability,bioactivity,biocompatibility,antibacterial properties,or catalytic *** strategies consist of incorporating of micro and nanoparticles into the PEO layers to produce multi-functional surfaces or the formation of multi-layered coatings to cover the defects of PEO *** this perspective,the present paper aims to overview various nano/micro-enabled strategies to promote the properties of PEO coatings on magnesium *** main focus is given to the functional changes that occurred in response to the incorporation of various types of nano/micro-structures into the PEO coatings on magnesium alloys.

关键词： Plasma electrolytic oxidation Corrosion resistance Tribological properties Biological properties Micro and multi-layer coatings

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