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International Journal of Minerals,Metallurgy and Materials 2019年第7期26卷 858-868页

作者： A.V. Koltygin V.e. Bazhenov R.S. Khasenova A.A. Komissarov A.I. Bazlov V.A. Bautin Foundry Department National University of Science and Technology “MISiS” Moscow 119049 Russia Laboratory of Hybrid Nanostructured Materials National University of Science and Technology “MISiS” Moscow 119049 Russia Laboratory of Advanced Green Materials National University of Science and Technology “MISiS” Moscow 119049 Russia Department of Metallurgy Steel New Production Technologies and Protection of Metals National University of Science and Technology “MISiS” Moscow 119049 Russia

Zn is a commonly used alloying element for Mg alloys owing to its beneficial effects on mechanical properties. To improve the mechanical and corrosion properties of We43B Mg alloys, the effects of 0–0.7wt% Zn addition on the microstructure and properties of sample alloys were investigated. Addition of Zn to as-cast We43B alloy promoted the formation of the Mg12Nd phase;by contrast, after T6 heat treatment, the phase composition of We43B alloys with and without Zn addition remained mostly the same. A long-period stacking ordered phase was predicted by CALPHAD calculation, but this phase was not observed in either the as-cast or heat-treated Zn-containing We43B alloys. The optimum temperature and duration of T6 heat treatment were obtained using CALPHAD calculations and hardness measurements. Addition of Zn resulted in a slight reduction in the average grain size of the as-cast and T6 heat-treated We43B alloys and endowed them with increased corrosion resistance with little effect on their mechanical properties.

关键词： magnesium alloys corrosion resistance mechanical properties Zn addition

Langmuir Probe and Optical emission Spectroscopy Studies of Low-Pressure Gas Mixture of CO_2 and N_2

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Plasma Science and Technology 2010年第3期12卷 314-319页

作者： e.F.MeNDeZ-MARTINeZ P.G.ReYeS D.OSORIO-GONZALeZ F.CASTILLO H.MARTINeZ Faculty of Sciences Autonomous University of the State of Mexico Institute of Nuclear Sciences Autonomous National University of Mexico Institute of Physical Sciences Autonomous National University of Mexico

Optical emission spectroscopy was used to study a gas mixture glow discharge of CO2 and N2 at a total pressure of 1.2 Torr, a power of 100 W and a flow of 16.5 L/min. The emission bands were measured in the wavelength range of 200 nm to 900 nm. The principal species observed were O2^＋（A^2П→ X^2П）, CO^＋（A^2П→X^2∑）, N2^＋（B^2∑u＋ → X^2∑g^＋）, CO2^＋（A^2∏ → X^2∏）, N2（C^3∏u → B^3∏g）, O2（b^1∑g^＋→ X^3∑g^-）, and CO （a^r3∑→a^3∏）. The behavior of the band intensities as a function of the N2 percentage is consistent with recent Monte Carlo simulations. The electron temperature and ion density were determined by a double Langmuir probe. The electron temperature was found in the range of 1.55 eV to 2.93 eV, and the electron concentration in the order of 10^10 cm^-3. The electron temperature and ion density at pure N2 and pure CO2 agree with previous measurements.

关键词： optical emission spectroscopy glow discharge electron temperature CO2 N2

球头铣刀铣削模式与切削性能的计算机辅助预报

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中国机械工程 2002年第24期13卷 2108-2110页

作者：康德纯王殿龙 Armarego e J A 大连理工大学机械工程学院澳大利亚墨尔本大学(Mel-bourne

讨论并建立了球头铣刀切削几何参数数学模型和铣削过程中切削力、扭矩及切削功率计算机预报数学模型。分析了球头铣刀的铣削模式和铣削中刀具—工件的干涉过程。以车削斜角切削数据库为基础,实现了平面前刀面球头铣刀铣削性能的计算机预... 详细信息

讨论并建立了球头铣刀切削几何参数数学模型和铣削过程中切削力、扭矩及切削功率计算机预报数学模型。分析了球头铣刀的铣削模式和铣削中刀具—工件的干涉过程。以车削斜角切削数据库为基础,实现了平面前刀面球头铣刀铣削性能的计算机预报,并通过数值模拟和切削实验对所建立的数学模型进行了验证。

关键词：球头铣刀铣削模式切削性能计算机辅助预报

Studies on the Reaction Between α－Acetylthioformanilide and o-Phenylenediamine

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Chemical Research in Chinese Universities 1994年第3期10卷 175-178页

作者： ZOU Jian-ping ZHeN Ren-sheng ZHAO Bei FANG Dong LU Zhong-e Department of Chemistry Suzhou UniversitySuzhou215006

,3-Disubstituted quinoxalines were synthesized from α-acetylthioformanilide and ophenylenediamine. Further studies sliowed that there existed competitive re- actions. One was a condensation reaction which produced su... 详细信息

关键词： α-Acetylthioformanilide o-Phenylenediamine 2, 3-Disubstituted quinoxaline

Using SWAT to simulate crop yields and salinity levels in the North Fork River Basin,USA

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International Journal of Agricultural and Biological engineering 2015年第3期8卷 110-124页

作者： Aaron R.Mittelstet Daniel e.Storm Art L.Stoecker Department of Biosystems and Agricultural engineering Oklahoma State UniversityStillwaterOklahoma 74078USA Department of Agricultural economics Oklahoma State UniversityStillwaterOklahoma 74078USA

Crop yields and salinity levels in the North Fork of the Red River(North Fork River)basin,located in southwestern Oklahoma and the Texas Panhandle,were analyzed based on the diverse climate in the *** irrigation water is a major problem in the *** elm Fork Creek flows through salt deposits,making the creek and its receiving stream,the North Fork River,too saline to use for *** greatly reduces the number of hectares that can be utilized for agricultural crops within the basin.A baseline SWAT model was setup,calibrated and validated to simulate streamflow and wheat and cotton *** SWAT model and a regression equation were used to analyze variable weather impacts on crop yields and salinity *** the weather generator WXGeN and 58 years of observed weather data,ten 50-year weather datasets were *** from the weather generator was input into the calibrated SWAT model to simulate wheat and dryland and irrigated cotton yields for the ten weather *** an empirical relationship between ionic strength and streamflow,salinity levels were *** the crop yields varied greatly from year to year,the yields were not significantly different over the 50-year simulation *** electrical conductivity(eC,expressed in decisiemens per meter or dS/m)at the US Geological Survey gage station just downstream of the salt deposits was significantly different with levels ranging from 40 to 65 dS/*** the water in the elm Fork is much too saline to use for irrigation,the water in the North Fork River may be used as long as the flow rates in the river are greater than 0.60 m3/*** order to optimize the available cropland,a salinity control must be installed upstream of the salt deposits on the elm Fork Creek.

关键词： salinity SWAT crop yield wheat modeling cotton modeling Red River

Analyzing stem cell dynamics： use of cutting edge genetic approaches in model organisms

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Frontiers in Biology 2015年第1期10卷 1-10页

作者： Gary R. HIMe Nicole SIDDALL Katja HORVAY Helen e. ABUD Department of Anatomy and Neuroseienee University of Melbourne VIC 3010 Australia Department of Anatomy and Developmental Biology Monash University Clayton VIC 3800 Australia

Regeneration of many cell types found in adult organs relies upon the presence of relatively small pools of undifferentiated stem cells. Initial studies that attempted to isolate stem cells and propagate them in vitro have been complemented by analysis of stem cells in their endogenous tissues where they are subject to a variety of regulatory cues. This has been facilitated by the advent of new methods for lineage tracing and genetic manipulation of stem cells and their associated niche cells. The picture that is emerging is that different stem cell populations utilize diverse processes to ensure maintenance of the stem cell pool accompanied by production of cells committed to regenerate differentiated cells.

关键词： stem cells Drosophila mouse testis intestine lineage tracing

Delensembleelec:Computing ensemble-Averaged electrostatics Using DelPhi

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Communications in Computational Physics 2013年第1期13卷 256-268页

作者： Lane W.Votapka Luke Czapla Maxim Zhenirovskyy Rommie e.Amaro Department of Chemistry and Biochemistry University of CaliforniaSan DiegoLa JollaCalifornia 92093USA Computational Biophysics and Bioinformatics Department of PhysicsClemson UniversityClemsonSC 29634USA

A new VMD plugin that interfaces with DelPhi to provide ensemble-averaged electrostatic calculations using the Poisson-Boltzmann equation is *** general theory and context of this approach are discussed,and examples of the plugin interface and calculations are *** new tool is applied to systems of current biological interest,obtaining the ensemble-averaged electrostatic properties of the two major influenza virus glycoproteins,hemagglutinin and neuraminidase,from explicitly solvated all-atom molecular dynamics *** differences between the ensemble-averaged electrostatics and those obtained from a single structure are examined in detail for these examples,revealing how the plugin can be a powerful tool in facilitating the modeling of electrostatic interactions in biological systems.

关键词： Delensembleelec ensemble-averaged electrostatics Poisson Boltzmann equation DelPhi molecular dynamics influenza glycoproteins

Influence of urbanization on the thermal environment of meteorological station:Satellite-observed evidence

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Advances in Climate Change Research 2015年第1期6卷 7-15页

作者： SHI Tao HUANG Yong WANG Hong SHI Chun-e YANG Yuan-Jian Key Laboratory of Atmospheric Sciences and Satellite Remote Sensing of Anhui Province Anhui Institute of Meteorological Sciences Wuhu Meteorological Bureau Nanjing University of Information Science and Technology

In this paper, five national meteorological stations in Anhui province are taken as typical examples to explore the effects of local urbanization on their thermal environment by using Landsat data from 1990 to 2010. Satellite-based land use/land cover(LULC), land surface temperature(LST), normalized difference vegetation index(NDVI) are used to investigate the effects. The study shows that LULC around meteorological stations changed significantly due to urban expansion. Fast urbanization is the main factor that affects the spatial-temporal distribution of thermal environment around meteorological stations. Moreover, the normalized LST and NDVI exhibit strong inverse correlations around meteorological stations, so the variability of LST can be monitored through evaluating the variability of NDVI. In addition, station-relocation plays an important role in improving representativeness of thermal environment. Notably, the environment representativeness was improved, but when using the data from the station to study climate change, the relocation-induced inhomogeneous data should be considered and adjusted. Consequently,controlling the scale and layout of the urban buildings and constructions around meteorological stations is an effective method to ameliorate observational thermal environment and to improve regional representativeness of station observation. The present work provides observational evidences that high resolution Landsat images can be used to evaluate the thermal environment of meteorological stations.

关键词： Urbanization Thermal environment Representativeness Land surface temperature Normalized difference vegetation index (NDVI)

electromyographic and Mechanomyographic Responses During Isokinetic Leg extensions in Children Versus Adolescents

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Journal of Science in Sport and exercise 2023年第3期5卷 226-235页

作者： Zachary M.Gillen Marni e.Shoemaker Joel T.Cramer Department of Kinesiology Mississippi State University236 McCarthy GymnasiumStarkvilleMS 39762USA School of Health and Consumer Sciences South Dakota State UniversityBrookingsSDUSA College of Health Professions and Sciences University of Central FloridaOrlandoFLUSA

Purpose The purpose of this study was to examine peak torque(PT),mean power(MP),electromyographic(eMG)amplitude,mechanomyographic(MMG)amplitude,and neuromuscular efficiency from eMG and MMG amplitude(NMe_(eMG)and NMe_(MMG),respectively)across the velocity spectrum in children versus *** Seventeen children(n=8 males,n=9 females)and 22 adolescents(n=11 males,n=11 females)*** completed maximal concentric isokinetic leg extensions at 60,120,180,240 and 300°/***,MP,eMG amplitude,and MMG amplitude were quantified during all muscle ***_(eMG)and NMe_(MMG)were quantified by expressing PT relative to eMG and MMG amplitude,respectively,for each muscle *** PT,MP,NMe_(eMG),and NMe_(MMG)were greater for the adolescents than the children collapsed across sex and veloc-ity(P≤0.021).There were no significant differences for eMG amplitude(P≥0.051),while MMG amplitude increased significantly from 60 to 240°/s(Pen decreased significantly from 240 to 300°/s(Perall,regardless of velocity,the expression of PT relative to eMG and MMG amplitude(NMe_(eMG)and NMe_(MMG),respectively),in conjunction with measurements of torque and power production,may provide practitioners a unique method of examining growth and development-related augmentations in neuromuscular function during dynamic movements.

关键词： electromyography Mechanomyography Neuromuscular efficiency Growth and development

Photosensitivity and Hydroxyl in Hydrogenated Silica Fibers

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Chinese Physics Letters 1998年第9期15卷 657-658页

作者： TAN Gu LIN Xiang-zhi LIU Hong-du FU Li-bin e.Y.B.Pun P.S.Chung Department of Physics Peking UniversityBeijing 100871 Department of electronical engineering City University of Hong Kong

Optical loss spectra and refractive index changes have been measured in the hydrogenated standard telecommu-nication fiber and photosensitive *** index changes due to ultraviolet exposure were found to be closely related with the OH formation in both types of fibers.A direct photolyticd model is proposed to explain the effect of hydrogen loading on the enhancement of the photosensitivity in silica fibers.

关键词： loading ultraviolet effect