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Radiation Spectral Analysis of 3D Dust Molecular Clusters(PAHs)and Peptoids under Ionization and Electric Field in ISM

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Research in Astronomy and Astrophysics 2024年第1期24卷 70-77页

作者： Ruiqing Wu Chunhua Zhu Guoliang lü Xiaojiao Zhang Xizhen lu Jinlong Yu Wujin Chen Mengqiu long School of Physics and Electronics Central South UniversityChangsha 410083China School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China School of Microelectronics and Physics Hunan University of Technology and BusinessChangsha 410205China College of Mechanical and Electronic Engineering Tarim UniversityAlar 843300China School of Medicine Xinjiang Medical UniversityUrumqi 830011China

Polycyclic aromatic hydrocarbons(PAHs),PANHs,and peptoids dust spectral cal.ulations from the interstellar medium(ISM)are important for dust observations and *** goal is to cal.ulate the radiation spectrum of spherical PAHs dust clusters in a vacuum containing ionized and applied in the presence of an electric *** propose a new simple computational model to cal.ulate the size of three-dimensional spherical dust clusters formed by different initial dust *** the Vienna Ab-initio Simulation Package code,the density functional theory with the generalized approximation was used to cal.ulate the electron density gradient and obtain the radiation spectrum of *** the radius of spherical dust clusters is~[0.009-0.042]μm,the dust radiation spectrum agrees well with the Z=0.02 mMMP stellar spectra,and the PAHs radiation spectrum of NGC 4676 at wavelengths of(0-5]μm and(5-10]μm,*** the ionized state,the N-PAH,C_(10)H_(9)N,2(C_(4)H_(4))^(1+),and peptoids 4(CHON),(C_(8)H_(10)N_(2)O_(5))^(1+)dust clusters at 3.3μm,while the 2(C_(22)H_(21)N_(3)O_(2))^(1+),4(CHON)dust clusters at 5.2μm have obvious *** is a characteristic of part of PAHs and peptoids clusters radiation at the nearinfrared wavelength of 2μ***,especially after applying an electric field to the dust,the emission spectrum of the dust increases significantly in the radiation wavelength range[3-10]μ***,the dust clusters of PAHs,PANHs,and peptoids of the radius size~[0.009-0.042]μm are likely to exist in the ISM.

关键词： ISM:structure ISM:molecules radiation mechanisms:general (ISM:)dust extinction

Pumping-induced Well Hydraulics and Groundwater Budget in a leaky Aquifer System with Vertical Heterogeneity in Aquitard Hydraulic Properties

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 477-490页

作者： ZHuANG Chao lÜChenyang YAN long lI Yabing ZHOu Zhifang WANG Jinguo DOu Zhi Walter A.IllMAN School of Earth Sciences and Engineering Hohai UniversityNanjing 211100China School of Geography Earth and Environmental SciencesUniversity of BirminghamBirmingham B152TTU.K. Department of Modern Mechanics University of Science and Technology of ChinaHefei 230027China Department of Earth and Environmental Sciences University of WaterlooOntario N2L 3G1Canada

In groundwater hydrology,aquitard heterogeneity is often less considered compared to aquifers,despite its significant impact on groundwater hydraulics and groundwater resources evaluation.A semi-analytical solution is derived for pumping-induced well hydraulics and groundwater budget with consideration of vertical heterogeneity in aquitard hydraulic conductivity(K)and specific storage(S_(s)).The proposed new solution is innovative in its partitioning of the aquitard into multiple homogeneous sub-layers to enable consideration of various forms of vertically heterogeneous K or S_(s).Two scenarios of analytical investigations are explored:one is the presence of aquitard interlayers with distinct K or S_(s) values,a common field-scale occurrence;another is an exponentially depth-decaying aquitard S_(s),a regional-scale phenomenon supported by statistical *** investigations reveal that a low-K interlayer can significantly increase aquifer drawdown and enhance aquifer/aquitard depletion;a high-S_(s) interlayer can noticeably reduce aquifer drawdown and increase aquitard *** of low-K or high-S_(s) interlayers also significantly impact well hydraulics and groundwater *** the context of an exponentially depth-decaying aquitard S_(s),a larger decay exponent can enhance aquifer *** using current models with a vertically homogeneous aquitard,half the sum of the geometric and harmonic means of exponentially depth-decaying aquitard S_(s) should be used to cal.ulate aquitard depletion and unconfined aquifer leakage.

关键词： hydrogeology aquitard vertical heterogeneity semi-analytical solution well hydraulics groundwater budget

Wear of semi-solid rheocast SiC_p/Al metal matrix composites

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中国有色金属学会会刊：英文版 2010年第S3期20卷 852-856页

作者： u.A.CuRlE l.IVANCHEV Materials Science and Manufacturing Council for Scientific and Industrial Research(South Africa)

Rheocasting of plates in Al alloy 359 reinforced with SiC at 11%,27% and 50%(volume fractions) exhibits the capability of the council for scientific and industrial research-rheocasting system(CSIR-RCS) in rheo-processing and high pressure die casting of SiC metal matrix *** metal matrix consisting of nearly spherical proeutectic α(Al) globules was *** of fibrous eutectic silicon took place upon heat treatment of the as-cast metal matrix composites(MMCs).Hardness increases as the volume fractions of SiC *** rates of the MMCs in the F and T6 heat treatment conditions were assessed with a metallographic preparation *** is found that the 11% SiC MMC wear rate is higher on SiC abrasives compared with the 50% SiC MMC wear rate due to wear of the aluminum *** trend is reversed on diamond abrasives due to pull-out of the irregular shaped composite *** 50% SiC MMC suffers from composite particle fracture porosity after high pressure die casting(HPDC).

关键词： CSIR-RCS HPDC SiC F condition T6 condition wear rate hardness porosity

On the detection of closed orbits in time-dependent systems by using double-pulse lasers

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Communications in Theoretical Physics 2020年第9期72卷 111-117页

作者： S u Khan M l Du Institute of Theoretical Physics Chinese Academy of Sciences.Beijing 100190China university of Chinese Academy of Sciences Beijing100049China

In the photodetachment of atoms or negative ions by a double-pulse laser, the first pulse of the double-pulse laser generates waves and the delayed second pulse may detect them. The phenomenon of the excitation and detection of waves by a double-pulse laser can be used to identify the closed orbits in the system. We demonstrate this phenomenon with a negative hydrogen ion(H^-) by analyzing the total population excited by a double-pulse laser in a timedependent field for different physical parameters. By analyzing the total excited population using a double-pulse laser, we can uncover all the closed orbits existing in the system. We demonstrate that this can be realized by scanning the first pulse position and the time delay between the two pulses.

关键词： double-pulse laser detection of closed orbits photodetachment spectra time-dependent systems

Effect of densification distribution on the Young's modulus of porous coatings after nano-indentation

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Acta Metal.urgica Sinica(English letters) 2012年第5期25卷 383-390页

作者： Xiaojuan l.u Ping XIAO Haiyan lI School of Environment Science and Engineering North China Electric Power University Yonghua North Street Baoding 071000 China School of Materials The University of Manchester Manchester M1 7HS UK School of Mechanical Aerospace and Civil Engineering The University of Manchester P.O. Box 88Sackville Street Manchester M60 1QD UK

Nano-indentation of a porous ceramic coating leads to crushing and densification of the coating under the indenter. In this work, finite element simulations of indentation on the porous coating have been carried out to study the effect of the size and dis- tribution of densification on Youngts modulus measured by nano-indentation. Two totally different distribution patterns have been simulated in this work. In the case of gradient densification, the Youngts modulus increased by 8.6% when the densifi- cation has occurred in the maximum influenced area. While the Young^s modulus increased by 2% with a uniformed densification. Examinations of the cross-section of the coatings have suggested that the densification after the indentation is close to the second model. The measured Young＇s modulus could have differed by 2%. The effect of densification on the Young＇s modulus measured by using nano-indentation is strongly dependent on the densification patterns of the porous coating.

关键词： Film Mechanical property Finite element simulation Porosity Electron Microscopy

High strength and ductility of cast Mg-9Gd-1.5Y-0.8Zn-0.3Zr alloy achieved by microstructural regulation

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Progress in Natural Science:Materials International 2023年第6期33卷 797-803页

作者： Daiyi Deng renju Cheng Zhihua Dong Bin Jiang Mingbo Yang Haijun Wang Chuntang Yu Yanlong Ma Fusheng Pan College of Materials Science and Engineering Chongqing University of Technology College of Materials Science and Engineering Chongqing University

This work reports a high strength and ductility as-casted Mg-9Gd-1.5Y-0.8Zn-0.3Zr(wt.%) alloy by using the optimized heat treatment of a lower solid-solution temperature of 480°C and then aging at 200°C for 48 h with the ultimate tensile strength and yield strength reached 374(±2.0) MPa and 270.5(±5.5) MPa, respectively,whilst a high elongation of 10.1(±1.3) % was achieved. The high strength and ductility are found to emerged primarily from the synergic influence of long period stacking ordered(lPSO) phases and the nano-β’precipitates:at lower temperature of 480°C the alloy preserved a large number of block and lamellar 14H-lPSO phases at the grain boundaries and the smallest size of β’precipitates led to a better ductility and higher strength. While at higher temperatures solid-solution treatment of 500°C and 520°C, the strength and ductility declined slightly due to the lamellar or filminess lPSO formed in the grains, and especially the precipitation of cubic-shaped REenriched phases and rod-like Zn–Zr compounds. Particularly when the solid solution temperature reached as high as 520°C, the strength was significantly reduced due to the increase of the cubic-shaped RE-enriched phases. We suppose that the efficiency of the morphology and position of lPSO phases on the ductility strengthening of the alloy is block and lamellar lPSO phases in the grain boundaries > lamellar or filminess lPSO phases in the grains.

关键词： Mg-Gd-Y-Zn-Zr alloy High strength and ductility Magnesium alloy lPSO phase Heat treatment

Surface Water Quality Profiling using Physicochemical Parameters in Open Defecation Free and Non-Open Defecation Free local Government Areas in Benue State, Nigeria

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Open Journal of Modern Hydrology 2024年第3期14卷 174-191页

作者： Moses T. Asoo Celestine u. Aguoru Innocent O. Ogbonna Hyacinth O.A. Oluma Benue State Ministry of Health Makurdi Nigeria Department of Plant Science and Biotechnology College of Biological Sciences Joseph Sarwuan Tarka University Makurdi Nigeria Department of Microbiology College of Biological Sciences Joseph Sarwuan Tarka University Makurdi Nigeria

Physicochemical parameters of surface water sources in the study of local government areas (lGAs) were assessed using standard procedures. The mean physicochemical parameters for pH (5.49), NO2 (0.23 mg/l), SO4 (0.77 mg/l), Na (28.72 mg/l), Ca (28.94 mg/l), Mg (17.50 mg/l), Cl (11.65 mg/l), TSS (6.27 mg/l), TDS (104.23 mg/l), BOD (2.83 mg/l) and F (0.87 mg/l) were below WHO standards irrespective of their defecation status. The values for electrical conductivity (EC) (2770.50 µs/cm, turbidity (481.24 NTu), dissolved oxygen (DO) (5.32 mg/l), chemical oxygen demand (COD) (445.50 mg/l), K (125.06 mg/l), PO4 (0.78 mg/l) and Fe (0.57 mg/l) were above the WHO limits for safe water. Higher EC and COD values obtained in the study is evidence of pol.ution of the water sources by organic matter.

关键词： Open Defecation Surface Water Water Quality Standard Physicochemical Parameters

The regulation of the Treg/Th 17 balance by mesenchyma stem cells in human systemic lupus erythematosus

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Cel.ular & Molecular Immunology 2017年第5期14卷 423-431页

作者： Dandan Wang Saisai Huang Xinran Yuan Jun liang renju Xu Genhong Yao Xuebing Feng lingyun Sun Department of Rheumatology and Immunology The Affiliated Drum Tower Hospital of Nanjing University Medical School Nanjing China

Background and objective： umbilical cord （uC）-derived mesenchymal stem cells （MSCs） have shown immunoregulation of various immune cells. The aim of this study was to investigate the mechanism of uC MSCs in the regulation of peripheral regulatory T cells （Treg） and T helper 17 （Th17） cells in patients with systemic lupus erythematosus （SlE）. Methods： Thirty patients with active SlE, refractory to conventional therapies, were given uC MSCs infusions. The percentages of peripheral blood CD4＋CD25＋Foxp3＋ regulatory T cells （Treg） and CD3＋CD8-1l17A＋ Th17 cells and the mean fluorescence intensities （MFI） of Foxp3 and Il- 17 were measured at I week, I month, 3 months, 6 months, and 12 months after MSCs transplantation （MSCT）. Serum cytokines, including transforming growth factor beta （TGF-β）, tumor necrosis factor alpha （TNF-α）, interl.ukin 6 （Il-6）, and Il-17A were detected using ElISA. Peripheral blood mononuclear cells from patients were collected and co-cul.ured with uC MSCs at ratios of 1：1, 10：1, and 50：1, respectively, for 72 h to detect the proportions of Treg and Th17 cells and the MFIs of Foxp3 and Il-17 were determined by flow cytometry. The cytokines in the supernatant solution were detected using ElISA. Inhibitors targeting TGF-β, Il-6, indoleamine 2,3-dioxygenase （IDO）, and prostaglandin E2 were added to the co-cul.ure system, and the percentages of Treg and Th17 cells were observed. Results： The percentage of peripheral Treg and Foxp3 MFI increased 1 week, 1 month, and 3 months after uC MSCs transplantation, while the Th17 proportion and MFI of Il-17 decreased 3 months, 6 months, and 12 months after the treatment, along with an increase in serum TGF-β at I week, 3 months, and 12 months and a decrease in serum TNF-a beginning at I week. There were no alterations in serums Il-6 and Il-17A before or after MSCT. In vitro studies showed that the uC MSCs dose-dependently up-regulated peripheral Treg proportion in SlE patients, which was not depended on cell-cell co

关键词： mesenchymal stem cells regulatory T cells systemic lupus erythematosus T helper 17 cells umbilical cord

Effects of slag fineness on durability of mortars

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2007年第11期8卷 1725-1730页

作者： TOPu lker Bekir BlR Turhan Department of Civil Engineering Eski■ehir Osmangazi university Eski■ehir 26480 Turkey

In recent years, the usages of by-products and wastes in industry have become more important. The importance of the sustainable development is also of increasing. The utilizations of wastes, as mineral admixture or fine aggregate, reduce the consumption of the natural resources and improve the durability of concrete. In this study, the effect of the fineness on the high temperature and sulphate resistances of concrete mortar specimens, produced with ground granulated blast-furnace slag (GBFS) replacing cement, is investigated. The compressive and flexural strength test results for all series related to durability effects, exposing temperature and solutions, exposure times for these durability effects, slag content and fineness are discussed. Conse- quently, the optimum slag contents are determined for producing the sulphate and high temperature resistant mortars.

关键词： Cement Fineness Ground slag High temperature effect Sulphate attack Sustainable development