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Trace-Rare-Gas Optical Emission Spectroscopy of Nitrogen Plasma Generated at a Frequency of 13.56 mHz

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Plasma Science and Technology 2011年第2期13卷 208-212页

作者： N.u.REHmAN F.u.khan S.NASEER G.muRTAZA S.S.HuSSAIN I.AHmAD m.ZAKAuLLAH Department of Physics COMSATS Institute of Information Technology Department of Physics Gomal University Department of Physics Peshawar University Department of Physics Quaid-i-Azam University

Optical emission spectroscopic measurement of trace rare gas is carried out to determine the density of nitrogen （N） atom, in a nitrogen plasma, as a function of filling pressure and RF power applied. 2% of argon, used as an actinometer, is mixed with nitrogen. In order to normalize the changes in the excitation cross section and electron energy distribution function at different operational conditions, the Ar-I emission line at 419.83 nm is used, which is of nearly the same excitation efficiency coefficient as that of the nitrogen emission line at 493.51 nm. It is observed that the emission intensity of the selected argon and atomic nitrogen lines increases with both pressure and RF power, as does the nitrogen atomic density.

关键词： optical actinometry N atomic density EEDF RF plasma

mass Transfer： a Deciding Factor for the multiplicity of an Event in Deep Inelastic Collisions

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Chinese Physics Letters 2006年第10期23卷 2714-2716页

作者： Tabassum Nasir J.J.Baluch E.u.khan F.N.Khattak m.I.Shahzad Department of Physics Gomal University D.I. Khan Pakistan Department of Physics CIIT Islamabad Pakistan u.W.C. Gomal UniversityD.I.KhanPakistan physics Research Division PINSTECH Islamabad Pakistan

Intermediate stage of the three and four-pronged events is investigated in the reaction ^208Pb＋^197Au at beam energy 11.67 meV/u. multiprong events are analysed numerically using an empirical mass-dependent velocityrauge relation. using the measured three-dimensional coordinates of correlated tracks, it is possible to determine the quantities such as mass transfer and total kinetic energy loss. These quantities are then used to study the intermediate stage of the reaction. It has been observed that mass transfer and total kinetic energy loss at the first step of the reaction decides the multiplicity of an event at the second stage of the sequential fission process.

关键词： HEAVY-ION INTERACTION mICA TRACK DETECTORS CHANNELS FISSION u-238

O'Hare Airport roadway traffic prediction via data fusion and Gaussian process regression

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 721-732页

作者： Damola m.Akinlana Arindam Fadikar Stefan m.Wild Natalia Zuniga-Garcia Joshua Auld Department of mathematics and Statistics University of South FloridaTampaFL 33620USA Decision and Infrastructure Sciences Division Argonne National LaboratoryLemontIL 60439USA Applied mathematics and Computational Research Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Department of Industrial Engineering and management Sciences Northwestern UniversityEvanstonIL 60208USA Argonne National Laboratory Energy SystemsLemontIL 60439USA

This study proposes an approach of leveraging information gathered from multiple traffic data sources at different resolutions to obtain approximate inference on the traffic distribution of Chicago's O'Hare Airport ***,it proposes the ingestion of traffic datasets at different resolutions to build spatiotemporal models for predicting the distribution of traffic volume on the road *** to its good adaptability and flexibility for spatiotemporal data,the Gaussian process(GP)regression was employed to provide short-term forecasts using data collected by loop detectors(sensors)and supplemented by telematics *** GP regression is used to make predictions of the distribution of the proportion of sensor data traffic volume represented by the telematics data for each location of the ***,the fitted GP model can be used to determine the approximate traffic distribution for a testing location outside of the training *** in the transportation sector can find the results of this work helpful for making informed decisions relating to current and future transportation conditions in the area.

关键词： Spatio-temporal Data fusion Gaussian process multimodal data Airport traffic O'Hare Airport

Cell-type resolved transcriptomic approaches for dissecting selective vulnerability in neurodgeneration

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Neural Regeneration Research 2024年第7期19卷 1411-1413页

作者： Caleb A.Wood Nicholas m.Tran Department of Neuroscience Baylor College of MedicineHoustonTXUSA Department of molecular and Human Genetics Baylor College of MedicineHoustonTXUSA

A common feature among neurodegenerative conditions is that ce rtain neuronal populations are selectively vulnerable to loss(Fu et al.,2018).By corollary,other neurons are selectively resilient,suggesting they may possess unique features that support their survival.u nderstanding the basis of neuronal resilience or vulnerability would provide a logical strategy to identify factors that could be targeted therapeutically.

关键词： selective targeted

Annihilation of Antiprotons in Light Nuclei

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Chinese Physics Letters 2006年第7期23卷 1716-1718页

作者： m. A. Rana E. u. khan m. I. Shahzad I. E. Qureshi F. malik G. Sher S. manzoor H. A. khan Physics Research Division PINSTECH P. O. Nilore Islamabad Pakistan

CR-39 detectors have been exposed to a 5.9-meV antiproton beam using the low energy antiproton ring （LEAR） facility at CERN. At this energy, tracks of antiprotons appear in a CR-39 detector after 135 rain of etching in 6m NaOH at 70℃. Fluence of the antiproton beam has been determined using track density. We have also found tracks in the etched CR-39 detector at different depths （250-500μm）. These tracks have resulted from the annihilation of antiprotons with the constituents （H, C and O） of the CR-39 detector. The goal of the experiment is to develop a simple and low-cost method to study properties of antiparticles and those formed after annihilation of these particles with the target matter.

关键词： STOPPED ANTIPROTONS HEAVY-NuCLEI GEV/C

Optimization Study of Pulsed DC Nitrogen-Hydrogen Plasma in the Presence of an Active Screen Cage

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Plasma Science and Technology 2014年第5期16卷 460-464页

作者： A.SAEED A.W.khan F.JAN H.u.SHAH m.ABRAR m.ZAKA-uI-ISLAm m.KHALID m.ZAKAuLLAH National Centre for Physics Quaid-i-Azam University Campus Islamabad Department of Physics Gomal University Department of Physics Quaid-i-Azam University Department of Physics Hazara University Mansehra Department of Physics Faculty of ScienceUniversity of Jazan

A glow discharge plasma nitriding reactor in the presence of an active screen cage is optimized in terms of current density,filling pressure and hydrogen concentrations using optical emission spectroscopy（OES）.The samples of AISI 304 are nitrided for different treatment times under optimum *** treated samples were analyzed by X-ray diffraction（XRD） to explore the changes induced in the crystallographic *** XRD pattern confirmed the formation of iron and chromium nitrides arising from incorporation of nitrogen as an interstitial solid solution in the iron lattice.A Vickers microhardness tester was used to evaluate the surface hardness as a function of treatment time（h）.The results showed clear evidence of improved surface hardness and a substantial amount of decrease in the treatment time compared with the previous work.

关键词： optical diagnostics plasma nitriding austenitic stainless steel

The gold-telluride connection:Evidence for multiple fluid pulses in the Jinqingding telluride-rich gold deposit of Jiaodong Peninsula,Eastern China

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Geoscience Frontiers 2024年第3期15卷 146-165页

作者： Wenyan Cai mingchun Song m.Santosh Jian Li School of Resources and Environmental Engineering Shandong University of TechnologyZibo 255049China Hebei Key Laboratory of Strategic Critical mineral Resources Hebei GEO UniversityShijiazhuang 050031China School of Earth Sciences and Resources China University of Geosciences Beijing29 Xueyuan RoadBeijing 100083China Department of Earth Science University of AdelaideAdelaide SA 5005Australia

The mechanism of gold migration,enrichment,and precipitation in forming world-class gold deposits has been a topic of wide interest,particularly where these deposits are abundant in *** Jiaodong Peninsula in eastern China hosts some of the world-class gold deposits among which the Jinqingding deposit is one of the best examples with substantial telluride mineralization and thus provides opportunity to investigate the genetic connection between tellurium and gold *** orebody in this deposit is hosted in the NE-NNE-trending Jiangjunshi-Quhezhuang fault with the Jurassic Kunyushan granitic pluton as wall *** deposit involved three mineralization stages as inferred from assemblages and crosscutting relationships between *** stages are:(I)pre-ore gold-poor quartz-pyrite veins,(II)main ore auriferous quartz-pyrite-Te/Bi-minerals±sphalerite±chalcopyrite±barite±marcasite veins,and(III)post-ore quartz-calcite *** present here the textural,isotopic,and geochemical variations of different stages/generations of pyrite based on scanning electron microscopy-energy dispersive spectroscopy(SEm-EDS),electron probe microanalysis(EPmA),and laser ablation inductively coupled plasma mass spectrometry(LA-ICP-mS).Pyrite in the Jinqingding deposit displays distinct ***1a shows a porous and dissolution-reprecipitation texture in the core,whereas Py1b exhibits a smooth and flat *** analysis reveals contrasting elemental compositions,with Py1a characterized by low Au(avg.0.14 ppm),As(avg.15.57 ppm),Ag(avg.17.71 ppm),and Te(avg.19.22 ppm)contents,but elevated Co(avg.1068.10 ppm)and Ni(224.12 ppm)concentrations,and variable sulfur isotopic composition(δ^(34)SV-CDT=9.54‰-12.12‰).Conversely,Py1b displays increased concentrations of these elements and a more concentratedδ^(34)SV-CDT value(11.99‰-12.23‰),possibly associated with weak coupled dissolution-reprecipitation(CDR)*** Stage II,pyrite can be further categorized

关键词： Episodic fluid pulses Sulfur reservoir Gold-Te precipitation Jinqingding deposit Jiaodong Peninsula

Nitriding molybdenum: Effects of duration and fill gas pressure when using 100-Hz pulse DC discharge technique

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Chinese Physics B 2014年第10期23卷 349-356页

作者： u.Ikhlaq R.Ahmad m.Shafiq S.Saleem m.S.Shah T.Hussain I.A.khan K.Abbas m.S.Abbas Department of Physics Government College University Centre for Advanced Studies in Physics (CASP) Government College University Department of Physics Quaid-i-Azam University Department of Physics GC University Faisalabad

molybdenum is nitrided by a 100-Hz pulsed DC glow discharge technique for various time durations and fill gas pressures to study the effects on the surface properties of molybdenum. X-ray diffractometry （XRD）, scanning electron microscopy （SEm）, and atomic force microscopy （AFm） are used for the structural and morphological analysis of the nitrided layers. Vickers＇ microhardness tester is utilized to investigate surface microhardness. Phase analysis shows the formation of more molybdenum nitride molecules for longer nitriding durations at fill gas pressures of 2 mbar and 3 mbar （1 bar = 105 Pa）. A considerable increase in surface microhardness （approximately by a factor of 2） is observed for longer duration （10 h） and 2-mbar pressure. Longer duration （10 h） and 2-mbar fill gas pressure favors the formation of homogeneous, smooth, hard layers by the incorporation of more nitrogen.

关键词： pulsed DC glow discharge scanning electron microscopy atomic force microscopy microhard-ness

In vivo and in vitro study of resorbable magnesium wires for medical implants:mg purity,surface quality,Zn alloying and polymer coating

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Journal of magnesium and Alloys 2024年第6期12卷 2472-2488页

作者： K.Tesar J.Luňácková m.Jex m.Žaloudková R.Vrbová m.Bartoš P.Klein L.Vištejnová J.Dušková E.Filová Z.Sucharda m.Steinerová S.Habr K.Balík A.Singh Department of materials Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueTrojanova 13Prague 12000Czech Republic Institute of Physics Czech Academy of SciencesNa Slovance 2Prague 18221Czech Republic Institute of Dental medicine First Faculty of MedicineCharles University and General University Hospital in PragueKaterinská32Prague 12801Czech Republic Department of Physics Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueBrehová7Prague 11519Czech Republic Department of Composites and Carbon materials Institute of Rock Structure and MechanicsCzech Academy of SciencesV Holešovickách 41Prague 18209Czech Republic Institute of Anatomy First Faculty of MedicineCharles UniversityU Nemocnice 3Prague 12800Czech Republic Biomedical Center Faculty of Medicine in PilsenCharles UniversityAlej Svobody 76Pilsen 32300Czech Republic Department of Pathological Physiology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Department of Histology and Embryology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Institute of Pathology First Faculty of MedicineCharles University and General University Hospital in PragueStudnickova 2Prague 12800Czech Republic Department of Biomaterials and Tissue Engineering Institute of PhysiologyCzech Academy of SciencesVidenska 1083Prague 14200Czech Republic Research Center for Structural materials National Institute for Materials Science1-2-1 SengenTsukuba 305-0047Japan

magnesium is an excellent material in terms of biocompatibility and its corrosion products can serve as an active source for new bone ***,localized corrosion and H_(2)generation limit the potential of mg-based *** low-alloyed mg-Zn wires can strongly reduce problems with large H_(2)bubbles and improve the mechanical properties considerably while maintaining excellent long-term *** pickling and a polymer coating can be effectively used to lower the rate of in vivo *** this work,microstructural,mechanical,and in vitro characterization of 250μm and 300μm extruded wires made from ultra-pure mg,commercially pure mg,mg-0.15Zn,mg-0.4Zn and mg-1Zn was ***,mg-0.4Zn wires together with a variant coated with a copolymer of L-lactide andε-caprolactone were tested in vivo on artificially damaged Wistar rat *** on the observed mg-induced osteogenesis,polymer-coated mg wires with a small addition of Zn are a perspective material for bone-support applications,such as cerclage and fixation wires.

关键词： magnesium Resorbable mg wire mg-Zn implant degradation Biocompatibility study Zn grain boundary segregation