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journal of Magnesium and Alloys 2021年第4期9卷 1311-1335页

作者： A.R.Eivani h.Vafaeenezhad h.R.jafarian j.Zhou school of metallurgy and materials engineering iran university of science and technology^nartnaktehraniran department of biomechanical engineering delft university of technologymekehveg 22628 cd delftthe netherlands

The faults in welding design and process every so often yield defective parts during friction stir welding(FsW).The development of numerical approaches including the finite element method(FEM)provides a way to draw a process paradigm before any physical *** is not practical to simulate all possible designs to identify the optimal FsW practice due to the inefficiency associated with concurrent modeling of material flow and heat dissipation throughout the *** study intends to develop a computational workflow based on the mesh-free FEM framework named smoothed particle hydrodynamics(sPh)which was integrated with adaptive neuro-fiizzy inference system(ANFIs)to evaluate the residual stress in the FsW *** integrated sPh and ANFIs methodology was established and the well-trained ANIs was then used to predict how the FsW process depends on its *** verify the sPh calculation,an itemized FsW case was performed on AZ91 Mg alloy and the induced residual stress was measured by ultrasonic *** suggested methodology can efficiently predict the residual stress distribution throughout friction stir welding of AZ91 alloy.

关键词： Friction stir welding(FsW) smoothed particle hydrodynamics(sPh) Adaptive neuro-fuzzy inference system(ANFIs) Ultrasonic Residual stress

second to fourth digit ratio (2D:4D) and testosterone in men

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Asian journal of Andrology 2004年第3期6卷 211-215页

作者： j.T.Manning s.Wood E.Vang j.Walton P.E.bundred c.van heyningen D.I.lewis-jones Department of Psychology University of Central LancashirePreston PR1 2HEUK Reproductive Medicine Unit Liverpool Women's HospitalCrown StreetLiverpool L8 7SSUK Department of Medical Imaging The University of LiverpoolPO Box 147Liverpool L69 3BXUK Department of Primary care The University of LiverpoolLiverpool L69 3GXUK University hospital Aintree Liverpool L9 7ALUK Department of Obstetrics & Gynaecology University of LiverpoolLiverpool Women's HospitalCrown StreetLiverpool L8 7SSUK

Aim: To investigate the relationship between 2D:4D and testosterone in men attending an infertility clinic and men drawn from the general population. Methods: Data on 2D:4D and testosterone from two samples were collected: (1) 43 men attending an infertility clinic, and (2) 51 men drawn from the general population without regard to fertility. Results: In sample (1) there were negative associations between 2D:4D and testicular function, and men with lower 2D:4D in their right compared to left hand had higher testosterone levels than men with higher 2D:4D in their right compared to left hand. sample (2) showed no significant associations between 2D:4D or side differences in 2E>:4D and testosterone. conclusion: Adult levels of testosterone may be related to aspects of 2D:4D in samples which contain men with compromised testicular function, but not in men from normative samples. Associations between 2D:4D and fertility-associated traits probably arise from early organisational effects of testosterone rather than from activational effects of current testosterone.

关键词： 2nd to 4th digit ratio 2D:4D testosterone

characteristics of chemistry and stable isotopes in groundwater of the chaobai River catchment,beijing

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Characteristics of chemistry and stable isotopes in groundwa...

A sTUDY OF cARbIDE GROWTh IN MAR-M247 lc AllOY bY DIREcTIONAl sOlIDIFIcATION METhOD

中国科学院地质与地球物理研究所2013年度（第13届）学术年会

作者： j.li j.liu Z.Pang x.Wang key laboratory of Engineering Geomechanics Institute of Geology and GeophysicsChinese Academy of Sciences University of chinese Academy of sciences hydrogeology and Engineering Geology Team of beijing

Environmental isotopes and chemical compositions are useful tools for the study of groundwater flow systems. Groundwater of the chaobai River catchment,beijing was sampled for chemical and stable isotopes analyses in *** signatures evolve progressively from caMg-hcO to NaK-hcO,and then to Na-hcO compositions as groundwater flows from the mountain to discharge *** can be divided into two groups on the basis of stable isotope compositions:ancient groundwater and modern *** groundwater(-9.9‰to -6.6‰forδO) plots along a line with a slope of 4.0 on a 8 h versus 8 O diagram,reflecting evaporation during the process of recharge,whereas ancient groundwater samples(30 to 12 Ka.) are different in isotopic composition(-11.0‰and -68.2‰forδO andδh,respectively),reflecting the cold and arid climate in the last glacial *** results have important implications for groundwater management in beijing city.

关键词： Groundwater chemical characteristics stable isotopes 14c age chaobai catchement

来源： cnki会议评论

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Acta Metallurgica sinica(English letters) 1996年第6期9卷 509-514页

作者： j.h lee j. chen s.j. choe Y.T. lee and h.M. Kim(high Temperature Materials laboratory, Korea Institute of Machinery & Materials, 66 sangnam Dong,changwon, Kyungnam,641010, Korea ) Korea Inst of machinery & Materials Changwon South Korea

The carbide growth behavior of MAR-M247 lc alloy was investigated by directional solidification and quench method. The carbide volume fraction, trapping and growth behavior were correlated with the growth *** was found that the carbide volume fraction decreased at slower growth *** decreasing was caused by lower solidliquid interface trapping ability at slower growth rate.

关键词： carbide,directional solidification,trapping growth

simulation Experiment of loading Influence to Reinforcement corrosion Affected by stray current and salt solution

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武汉理工大学学报 2010年第17期32卷 147-151页

作者： TENG h W YANG s M shU Z c hUANG Y hUO D college of Architecture and civil Engineering Beijing University of TechnologyBeijing 100124China beijing key lab of Earthquake Engineering and structural Retrofit Beijing University of TechnologyBeijing 100124China

According to the service environment of subway structure,experiment is carried out to simulate influence of different loading levels to reinforcement corrosion of R.c element affected by stray current and chlorine salt solution. The current density of the corrosion is measured with the linear polarization resistance method,together with the qualitative analysis and quantitative calculation. Experiment shows that rebar corrosion current density increase accordingly with the increase of loading level. The quantitative relations and the time of rust corrosion of reinforcement are obtained.

关键词： reinforcement corrosion stray current chloride ion solution loading level simulation experiment

高效液相色谱法测定儿科用药盐酸异丙嗪片的含量均匀度及分剂量研究

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实验室检测 2024年第8期2卷 99-103页

作者：赵雪娜孙晶金昌市药品检验检测中心金昌市中心医院

目的建立高效液相色谱法测定盐酸异丙嗪的含量均匀度，为后续研究儿科用药手工掰片后的含量均匀度和含量的质量提供可靠实验依据。方法采用高效液相色谱法，用十八烷基硅烷键合硅胶为填充剂的色谱柱，水（用冰醋酸调节p h值至2.3）-... 详细信息

目的建立高效液相色谱法测定盐酸异丙嗪的含量均匀度，为后续研究儿科用药手工掰片后的含量均匀度和含量的质量提供可靠实验依据。方法采用高效液相色谱法，用十八烷基硅烷键合硅胶为填充剂的色谱柱，水（用冰醋酸调节p h值至2.3）-甲醇（55∶45）为流动相，检测波长为254 nm。结果盐酸异丙嗪在17.392～26.088μg/m l范围内呈良好的线性关系，线性方程为：Y=55272x+348938(r2=0.9986)，方法回收率在100.22%～101.40%之间，RsD为0.49%，盐酸异丙嗪含量均匀度测定结果符合《中国药典》2020年版四部通则的规定。最后用此方法通过盐酸异丙嗪片的含量及含量均匀度对不同方法分剂量使用对儿童用药的准确性做相应分析。结论该方法测定盐酸异丙嗪含量均匀度和含量的专属性强，准确度和精密度均良好；儿童用药片分剂量使用的剂量准确性随分剂量次数的增加而降低。此研究为推动儿童用片剂药的剂量准确性提供了非常重要的数据理论和实际意义。

关键词：高效液相色谱法盐酸异丙嗪含量均匀度药片分剂量准确性儿童用药

三维高分辨黑血晚期钆增强成像改善心房瘢痕评估

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国际医学放射学杂志 2023年第4期 484-485页

作者： D.Y.si Y.F.Wu j j.xiao x.h.Qin R.Guo b.W.liu 秦桂姣

摘要射频消融(RFA)是一种广泛应用于房颤的治疗方法，可降低心律失常的风险。心房瘢痕的详细可视化和量化有可能改善术前决策和术后预后。传统的亮血晚期钆增强

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corrosion Inhibition of Mild steel in sulphuric Acid Using luffa Aegyptiaca leaves Extract

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Acta Metallurgica sinica(English letters) 2014年第6期27卷 969-980页

作者： s. jyothi j. Ravichandran Post Graduate and Research Department of chemistry Sri Ramakrishna Mission Vidyalaya College of Arts and Science

The corrosion inhibition of mild steel（Ms） in sulphuric acid using luffa aegyptiaca（lA） leaves extract was investigated by weight loss studies, colorimetric measurements, potentiodynamic polarisation and electrochemical impedance spectroscopy. The adsorption of lA leaves extract was confirmed by Fourier transform infrared spectroscopy and optical profilometry. The inhibition efficiency increased with increasing concentration of the extract but decreased with rise in temperature and with the increase in acid strength. Furthermore, the inhibition efficiency synergistically increased on the addition of halide ions. Polarisation studies revealed that the lA extract acts as mixed- type inhibitor. Physical adsorption mechanism is proposed from the trend in inhibition efficiency with the change in temperature and from thermodynamic parameters. The adsorption of lA on Ms surface obeys langmuir adsorption isotherm and follows the kinetic thermodynamic model of ElAwady at all temperatures studied.

关键词： Mild steel Adsorption corrosion Thermodynamic properties FTIR

special Mappings with central Values on Prime Rings

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Algebra colloquium 2020年第3期27卷 405-414页

作者： h.El Mir A.Mamouni l.Oukhtite laboratory of Modelling and Mathematical structures Department of Mathematics Faculty of Science and Technology of Fez Box 2202University S.M.Ben Abdellah FezMorocco Department of Mathematics Faculty of Science and Technology Box 509-BoutalamineUniversity Moulay IsmailErrachidiaMorocco

In this paper we investigate commutativity of prime rings with involution*of the second kind in which endomorphisms satisfy certain algebraic ***,we provide examples to show that the various restrictions imposed by th... 详细信息

关键词： prime ring involution commutativity derivation generalized derivation