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Journal of Thermal Science 1997年第4期6卷 286-297页

作者： h.sun C.F.Ma 等 DepartmentofThermalScience＆Engineering BeijingPolytechnicUniversityBeijing100022China DepartmentofT

Using seven working fluids, a systematic experimental study was performed to investigate the local convective heat transfer from vertical heaters to impinging circular submerged jets in the range of Reynolds number between 1.17 ×102 and 3.69 × 104 with the emphasis placed on the examination of Prandtl number dependence. heat transfer coefficiellts at the stagnation point were collected and correlated with the plate held within and beyond the potential core. Radial distribution of the local heat transfer coefficient was measured with five test liquids. Based on the measured profiles of the local heat transfer, a correlation was developed to cover the entire range of the radial distance. Besides the presellt data, the correlations developed in this work were also compared with a large quantity of available data of circular air jets. General agreement was observed between the air data and the correlat ions.

关键词： forced convection jets Prandtl number

Improvement of Coercivity and Corrosion Resistance of Nd-Fe-B Sintered Magnets with Cu Nano-particles Doping

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Journal of Materials Science & Technology 2012年第10期28卷 927-930页

作者： C.sun W.Q.Liu h.sun M.Yue X.F.Yi J.W.Chen College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China Earth-panda Advance Magnetic Material Co. Ltd.Anhui 231500China

Nd-Fe-B permanent magnets with a small amount of Cu nano-particles doping have been prepared by con-ventional sintered method. Effects of Cu content on magnetic properties, corrosion resistance, and oxidation properties of the magnets have been studied. It shows that the coercivity rises gradually, while the remanence decreases simultaneously with increasing Cu doping amount. Microstructure observation reveals that Cu ele- ment enriches mainly the Nd-rich phase. Autoclave test results show that the corrosion rate of the magnets decreases with increasing Cu content. After oxidation, the maximum energy product loss of the magnets with 0 and 0.2 wt% Cu nano-particles doping are 6.13% and 0.g9%, respectively. Therefore, it is concluded that Cu nano-particles doping is a promising way to enhance the coercivity and corrosion resistance of sintered Nd-Fe-B magnets.

关键词： Nd-Fe-B Cu nano-particles Coercivity Corrosion resistance Oxidation

Correlation between microstructure and mechanical properties of columnar crystals in the directionally solidified Mg-Gd-Y-Er alloy

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Journal of Magnesium and Alloys 2022年第3期10卷 806-818页

作者： D.R.Fang S.S.Zhao X.P.Lin T.Chai Y.Kuo h.sun Y.Dong School of Materials Science and Engineering Northeastern UniversityNo.11Alley 3Wenhua RoadHeping DistrictShenyangChina School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao 066004China

The Mg-4.58Gd-0.45Y-0.01 Er alloys with different volume fractions of columnar crystals in hard orientation(orientation factor ofbasal plane slip system is less than 0.2)were prepared by changing the pulling rate to regulate the crystal growth *** tests were performed on the Mg-4.58Gd-0.45Y-0.01 Er alloy at room temperature,and the structure after deformation was investigated by electron backscatter diffraction(EBSD).Subsequently,the strengthening mechanism of columnar crystals in hard orientation was *** results show if orientation factors ofbasal plane slip system of columnar crystals are all greater than 0.4(soft orientation),the alloy has low yield strength σ_(s)(64 MPa),but great work hardening ability,and ultimate tensile strength σ_(b) and elongationδare 114 MPa and 37.3%,*** orientation factors ofbasal plane slip system of columnar crystals are all less than 0.2(hard orientation),the alloy has high strength(σ_(s),125 MPa),but poor plasticity(δ,6.32%).If the"hard orientation"and the"soft orientation"columnar crystals are arranged alternately along the direction perpendicular to the crystal growth,the alloy has both superior strength(σ_(s),102 MPa)and excellent plasticity(δ,22.5%)at room *** improved comprehensive mechanical property can be attributed to two *** the one hand,the"hard orientation"columnar crystals can prevent the"soft orientation"crystals deforming,so the strength is *** the other hand,the"hard orientation"columnar crystals themselves can withstand a certain amount of deformation to retain appropriate plasticity.

关键词： Directional solidification Mg-Gd-Y-Er alloy hard orientation Mechanical prop

1,3-二氟丙烷构象和电子结构的从头算和密度泛函理论计算

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化学学报 1998年第10期56卷 948-955页

作者：吴德印任译刘玉明田安民 h.sun 四川大学化学系成都610064 MSI

用从头算和密度泛函理论研究了1,3-二氟丙烷的构象和电子结构.在计算的各种理论水平下,GG构象是最稳定构象,AG构象次之.利用分子力场的非键作用定量化旁式效应,由MM2力场的非键参数计算的结果较为合理.对于GG和AG构象,在hF/6-31G和hF/6-... 详细信息

用从头算和密度泛函理论研究了1,3-二氟丙烷的构象和电子结构.在计算的各种理论水平下,GG构象是最稳定构象,AG构象次之.利用分子力场的非键作用定量化旁式效应,由MM2力场的非键参数计算的结果较为合理.对于GG和AG构象,在hF/6-31G和hF/6-31+G水平预测的构象分布与实验值接近.

关键词：从头算构象旁式效应二氟丙烷电子结构

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液态氮的量子力学力场

四川大学学报（自然科学版） 1998年第2期35卷 240-244页

作者：任译杨捷吴德印田安民 h.sun S.J.Mumby 四川大学化学系

用分子动力学模拟方法，重新确定了液氮的范德瓦尔参数．结合光谱数据，建立了适用于计算机模拟的Ｎ２的位能函数，函数形式采用量子力学力场．所得的范德瓦尔参数σ等于３．７９６，ε等于０．２４９８ｋＪ／ｍｏｌ．用得到的Ｎ２的... 详细信息

用分子动力学模拟方法，重新确定了液氮的范德瓦尔参数．结合光谱数据，建立了适用于计算机模拟的Ｎ２的位能函数，函数形式采用量子力学力场．所得的范德瓦尔参数σ等于３．７９６，ε等于０．２４９８ｋＪ／ｍｏｌ．用得到的Ｎ２的位能函数对２１６个Ｎ２分子在三个不同温度下进行分子动力学模拟，计算了液氮的密度和蒸发热，计算结果和实验值的误差大约分别为１％和２％．

关键词：液氮位能函数量子力学力场分子动力学模拟

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土壤胶体之代换性盐基对于磷酸固定量之影响

土壤学报 1950年第2期 123-129页

作者：孙义国立浙江大学农业化学系

土壤中磷酸固定作用每受外界环境之影响而有很大差异,如粘土矿物的种类,土壤反应,代换性盐基等,黏土矿物与土壤反应对于磷酸固定前,人已有较详细之报告,本文特重视代换性盐基之种类对于磷酸固定之关系。本试验以紫色土与黄壤为代表,均... 详细信息

土壤中磷酸固定作用每受外界环境之影响而有很大差异,如粘土矿物的种类,土壤反应,代换性盐基等,黏土矿物与土壤反应对于磷酸固定前,人已有较详细之报告,本文特重视代换性盐基之种类对于磷酸固定之关系。本试验以紫色土与黄壤为代表,均取于北碚。紫色土系发育于白垩纪自流井层紫色页岩,属中性而无石灰性反应,ph=7.0,黄壤系自侏罗纪灰色砂岩风化者,心土微红,ph=4.5—5.0,为避免过高之有机质,均采取心土,按照 Stoke 氏定律提取5微米（micron）直径之黏土粒,晒干后,分别以 N NaCl,N KGl,N Nh4Cl,N MgCl2,N BaCl2及 ph=3 hCl 处理,然后再以90%酒精洗涤至无氯为止,总之以不变更胶体之构造为原则,经处理之黏土,先分析其中之代换性盐基以及盐基代换总量,然后再测定其磷酸固定量,在酸性反应如 h-黏土,其磷酸固定之主要因子为水化铁及水化铝,故再以 ph=2之盐酸淋洗,除去其中游离铁铝,再测定其磷酸固定量以资比较。按分析结果,黄壤胶体（Mg-黏土>h-黏土>B（?）-黏土>Nh4-黏土>K-黏土>Na 黏土 3.各种不同代换性盐基的粘土,加磷酸溶液后,其反应亦各不相同,h-黏土之 ph 值为3.2—4.5,因其酸度较高,溶液中之游离铁与游离铝含量较多,是故磷酸固定量亦较高,如以淡盐酸（ph=2）洗涤,除去其中游离铁铝后,其磷酸固定量则大为减少,Na-黏土与 K-粘土之溶液中,因 Oh 离子较多（ph=8.0—8.6）,而磷酸钠与磷酸钾又为水溶性,故磷酸固定量为最少。Ca-粘土与 Mg-粘土其反应属中性至微碱性,ph=7.5—8.0,因溶液中 Ca,Mg 离子浓度较高,磷酸则为此 Ca,Mg离子所固定,故在中性土壤中,磷酸固定以 Ca 为其主要在子,酸性土壤则以水化铁为其主要因子。 4.钙粘土所固定之磷酸,如以0.002 N h2SO4提取,其所固定之磷酸复可溶解,是项固定之磷酸与 heck 所称「暂时固定磷酸」颇为相似。

关键词：磷酸固定盐基差异土壤胶体

GCMC study hydrogen adsorption on MOFs with Ab initio force field

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GCMC study hydrogen adsorption on MOFs with Ab initio force ...

Molecular simulation of solubility and diffusion of water in polymer electrolyte membranes

第九届全国氢能学术会议

作者： J.Fu,X.F.Li,L.F.Zhao,h.sun Shanghai Jiao Tong University,China

＜正＞MOFs are potential materials for hydrogen storage,but several key issues need to be solved before making this kind of materials *** order to help design new MOF materials, we developed an ab initio force *** thi...

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Congenital penile curvature: long-term results of operative treatment using the plication procedure

第九届全国氢能学术会议

作者： X.F.Li,Y.Shi,Q.Chen,F.Li,h.sun Shanghai Jiao Tong University,China

＜正＞The proton conductivity and the mechanical property of the polymer electrolyte membranes（PEMs） depend heavily on the equilibrium water content of the polymer systems. Molecular simulation method was used to investigate the equilibrium solubility and diffusion of water in hydrated Nafion-117 and sulfonated polyarylenethioether sulfone polymer

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Asian Journal of Andrology 2004年第3期6卷 273-276页

作者： S.-S.Lee E.Meng F.-P.Chuang C.-Y.Yen S.-Y.Chang D.-S.Yu G.-h.sun Division of Urology Department of SurgeryTri-Service General HospitalNational Defense Medical CenterNationalDefense UniversityTaipeiChina

Aim: To determine the long-term outcome, effectiveness and patient satisfaction of congenital penile curvature correction by plication of tunica albuginea. Methods: From January 1992 to January 2002, 106 young patients underwent surgical correction of congenital penile curvature by corporeal plication. Indications for operation were difficult or impossible vaginal penetration and cosmetic problems. The technique of corporeal plication consists of placing longitudinal plication sutures of 2-zero braided polyester on the convex side of the curvature until the curvature is corrected when erection is artificially induced. Results of this procedure were obtained by retrospective chart reviews and questionnaires via mail. Long-term follow-up ranged from 11 to 132 (mean 69.3) months and data were available for 68 patients. Results: Penile straightening was excellent in 62 patients (91 %) and good with less than 15 degree of residual curvature in 6 patients (9 %). Sixty-seven patients reported no change in erectile rigidity or maintenance postoperatively, while 1 described early detumescence. Shortening of the penis without functional problems was noted by 26 patients (38 %). Thirty-Five patients (51 %) reported feeling palpable indurations (suture knots) on the penis. Temporary numbness of glans penis was described in 3 patients. Overall, 60 patients were very satisfied, 6 satisfied, 2 unsatisfied. Conclusion: Corporeal plication is an effective and durable procedure with a high rate of patient satisfaction.

关键词： penile curvature treatment plication procedure

Deposition of CrN Coatings by Filtered Cathodic Vacuum Arc

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Deposition of CrN Coatings by Filtered Cathodic Vacuum Arc