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金属毒性研究(Ⅱ)

中国有色金属学报 2002年第1期12卷 14-19页

作者：阮建明 m.h..rant 黄伯云中南大学粉末冶金国家重点实验室长沙410083 BioengineeringUnitStrathclydeUniversity

利用细胞生物学技术从定量和定性两个方面探讨了Cr(Ⅲ ) ,Cr(Ⅵ ) ,Ni,Al,Ag和V金属离子对生命组织的毒性作用。研究中发现 ,Cr(Ⅵ )对细胞DNA ,RNA合成限制最为显著 ,Ni和V金属离子在同等水平上妨碍RNA合成 ,随着离子浓度增加 ,Cr(Ⅲ ... 详细信息

利用细胞生物学技术从定量和定性两个方面探讨了Cr(Ⅲ ) ,Cr(Ⅵ ) ,Ni,Al,Ag和V金属离子对生命组织的毒性作用。研究中发现 ,Cr(Ⅵ )对细胞DNA ,RNA合成限制最为显著 ,Ni和V金属离子在同等水平上妨碍RNA合成 ,随着离子浓度增加 ,Cr(Ⅲ )离子对细胞DNA及RNA限制增大。Al离子对RNA合成限制大于对DNA合成。Ag离子对细胞DNA ,RNA合成限制作用相同。细胞谷胱甘肽 (GSh)还原能力强 ,是细胞最重要的解毒物质 ,也是细胞中防御毒性物质最关键的物质。细胞GSh还原能力定量分析表明 :微量的Cr(Ⅵ )即可导致细胞GSh下降。金属Ni离子破坏细胞骨架 ,使细胞内信息传递受阻 ,亦表现较强毒性。

关键词：金属毒性 DNA GSh 细胞

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金属毒性研究(Ⅰ)

中国有色金属学报 2001年第6期11卷 960-965页

作者：阮建明 m.h..rant 黄伯云中南大学粉末冶金国家重点实验室长沙410083 Bioengineering Unit Strathclyde University In Glasgow

采用体外细胞培养模式 ,通过测定细胞碱式磷酸酶 (ALP)活性及细胞四甲基偶氮砜 (mTT)还原能力 ,对构成金属和合金生物材料的金属离子 (Al,Ni,Cr ,V ,Ag)的毒性进行了定量评估 ,探讨了金属离子或原子对人体组织的毒害和腐蚀作用。结果表... 详细信息

采用体外细胞培养模式 ,通过测定细胞碱式磷酸酶 (ALP)活性及细胞四甲基偶氮砜 (mTT)还原能力 ,对构成金属和合金生物材料的金属离子 (Al,Ni,Cr ,V ,Ag)的毒性进行了定量评估 ,探讨了金属离子或原子对人体组织的毒害和腐蚀作用。结果表明微量六价铬离子表现出强烈的细胞毒性。当溶液离子度高于 10 0 μmol/L时 ,钒和镍亦表现强烈毒性。银离子和三价铬离子浓度高于 5 0 0 μmol/L后表现毒性。构成老年痴呆病成因的金属铝离子的毒性具有双向性。

关键词：生物材料金属毒性细胞分子生物学

熔融和辐射对垂直多孔嵌入微通道mhD混合对流换热的影响

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Journal of Central South University 2023年第11期30卷 3670-3681页

作者： A T AKINShILO A O ILEGBUSI h m ALI m SANUSI m G SOBAmOWO Department of mechanical Engineering University of LagosAkoka-YabaLagosNigeria Department of mechanical Engineering Yaba College of TechnologyLagosNigeria mechanical Engineering Department King Fahd University of Petroleum and MineralsDharan 31261Saudi Arabia Interdisciplinary Research Center of Renewable Energy and Power Systems(IRC-REPS) King Fahd University of Petroleum and MineralsDharan 31261Saudi Arabia Department of mechanical Engineering Obafemi Awolowo UniversityIle-IfeOsunNigeria

研究了导电和非导电两种壁型多孔微通道的熔融和滑移效应对混合对流换热的影响。采用高阶常微分非线性耦合模型,研究了横向磁场作用下流体在微通道内注入和喷出的流动力学。这些都是在通过相似变换完成的。采用解析解的同伦摄动方法对... 详细信息

研究了导电和非导电两种壁型多孔微通道的熔融和滑移效应对混合对流换热的影响。采用高阶常微分非线性耦合模型,研究了横向磁场作用下流体在微通道内注入和喷出的流动力学。这些都是在通过相似变换完成的。采用解析解的同伦摄动方法对控制热流体输运的力学模型进行了分析,并利用已有文献在简单条件下进行了验证并得到满意的结果。研究了流体输送过程中传热流变参数的影响,以提高系统运行效率,降低能耗,从而最大限度地降低成本。结果表明,熔体和辐射对热边界层的共同作用使热边界层的厚度逐渐减小。当辐射参数(R)在1

关键词：强化传热熔融微通道辐射优化多孔介质

Synthesis of nickel aluminate nanoceramic compound from aluminum and nickel carbonate by mechanical alloying with subsequent annealing

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Transactions of Nonferrous metals Society of China 2016年第11期26卷 2910-2915页

作者： m.JAVANmARDI R.EmADI h.AShRAFI Department of materials Engineering Isfahan University of Technology

The aim of present work was to produce pure nickel aluminate （NiAl2O4） nanoceramic compound by high energy millingof nickel carbonate （NiCO3） and aluminum （Al） powders followed by annealing. Phase composition, thermal behavior, morphologyand microstructure of powder samples were characterized by means of X-ray diffraction, differential scanning calorimeter,thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy. The results showed that formationof NiAl2O4 spinel compound from NiCO3 and Al powders took place in three steps： oxidation of Al to Al2O3, decomposition ofNiCO3 to NiO and CO2, and finally the solid state reaction between Al2O3 and NiO. It was also demonstrated that single phaseNiAl2O4 spinel compound can be produced by 5 h of mechanical milling with subsequent annealing of NiCO3/Al mixture at 900 Cfor 2 h, which is 冾 500 C lower than the temperatures used in the traditional solid state methods. The particle diameter of theproduced NiAl2O4 spinel compound was found to be less than 100 nm as measured by transmission electron microscopy.

关键词： nickel aluminate nanoceramic ball-milling annealing

Effects of heat input in friction stir welding on microstructure and mechanical properties of AA3003-h18 plates

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Transactions of Nonferrous metals Society of China 2015年第7期25卷 2147-2155页

作者： B.ABNAR m.KAZEmINEZhAD A.h.KOKABI Department of materials Science and Engineering Sharif University of Technology

The non-heat-treatable AA3003-h18 plates were joined by friction stir welding（FSW） to achieve a proper joint by optimizing the welding *** this purpose,the effects of heat input on microstructure and mechanical properties of the welded samples were investigated by changing the ratios of rotational speed（800-1200 r/min） to travel speed（40-100 mm/min）（w/v）.It was revealed that the grain growth rate was strongly increased with the increase of the heat input by rotational speed at constant travel speed,while the grain growth rate was slightly increased with the increase of the heat input by travel speed at constant rotational ***,hardness reduction was observed in the stir zone at higher rotational speed compared with that at lower *** interesting observation was that various welding parameters do not have noticeable effect on the tensile strength of the FSW ***,it has been observed that the fracture location of tensile test specimens was placed in the heat-affected zone（hAZ）on the advancing side at lower travel speed,while at higher travel speed,it was placed at the hAZ/thermomechanical affected zone（TmAZ） interface on the retreating side.

关键词： AA3003-h18 alloy friction stir welding heat input microstructure mechanical properties

Thermodynamic and kinetic analysis of CrB_(2) and VB_(2) formation in molten Al−Cr−V−B alloy

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Transactions of Nonferrous metals Society of China 2021年第10期31卷 3162-3176页

作者： A.KhALIQ h.T.ALI m.YUSUF Department of mechanical Engineering College of EngineeringUniversity of Ha’ilKingdom of Saudi Arabia School of Engineering RMIT UniversityMelbourneVIC 3000Australia Department of mechanical Engineering College of EngineeringTaif UniversityP.O.Box 11099Taif 21944Kingdom of Saudi Arabia Department of Clinical Pharmacy College of PharmacyTaif UniversityP.O.Box 11099Taif 21944Kingdom of Saudi Arabia

Transition metal impurities such as chromium(Cr)and vanadium(V)in solution deteriorate electrical conductivity of smelter grade aluminium(Al).These impurities can be removed from solution via boron treatment in which borides form upon their in-situ reaction with boron(B)-bearing ***,Cr removal from smelter grade Al solution is not well understood.A disagreement related to chromium boride(CrB_(2))formation in molten Al in the presence of other transition metals(V,Ti,Zr,Fe)by adding Al−B master alloy has been reported in *** study presents an effort to understand the mechanism of Cr removal from Al−0.50%Cr−0.50%V(mass fraction)alloy by adding Al−B(AlB_(12))master alloy at 1023 K in the Al alloy *** indicate that Cr removal from molten Al−0.50%Cr−0.50%V alloy by forming stable borides cannot be achieved at 1023 K;whereas excess of B in the solution preferentially forms aluminium boride(AlB2)over CrB_(2) during boron treatment of molten *** underlying kinetics of V removal from molten Al−0.50%Cr−0.50%V alloy revealed that early reaction stage is controlled by[B]/[V]mass transfer through liquid phase and mass transfer coefficient(km)was measured to be 9.6×10^(−4) m/*** later reaction stage was controlled by[B]/[V]diffusion through boride(VB_(2))*** study,therefore,advocates to investigate alternative ways to remove Cr from molten Al.

关键词： boron treatment Al CrB_(2) VB_(2) thermodynamics kinetics

Effects of wall wetting and in-cylinder fuel distribution in an advanced turbo-charged engine

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Journal of Central South University 2022年第7期29卷 2165-2178页

作者： ROSTAmPOUR A ShOJAEEFARD m.h..OLAEImANESh G R SAFAEI-ARShI A School of Automotive Engineering Iran University of Science and TechnologyNarmakTehran ***Iran School of mechanical Engineering Iran University of Science and TechnologyNarmakTehran ***Iran

One of the proposed concepts for spark ignition engines is advanced port fuel injection(APFI),which suggests using two port injectors for each *** this research,we numerically examine the capabilities of this concept in reducing fuel consumption and increasing engine *** results demonstrated that the use of this concept is very effective due to the use of two injectors and the possibility of reducing the spraying time and bringing the injection start time closer to the air inlet valve opening *** maximum amount of fuel film formed on the walls is reduced by about 75%,naturally,which leads to better and more homogeneous fuel distribution inside the combustion chamber and increases combustion *** results showed that under the same boundary conditions and engine operating point,the use of two port injectors for each cylinder leads to an increase of more than 20%of the maximum combustion chamber pressure and about 4%combustion *** the other hand,fuel film formation becomes worse in cold *** in this study,the capabilities of this concept in cold conditions were investigated *** have shown that the advanced port fuel injection,unlike conventional engines,is almost insensitive to inlet temperature changes.

关键词： advanced port fuel injection(APFI) fuel film fuel distribution wall wetting heat transfer phenomena

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恶性贫血14例临床分析

西南国防医药 2003年第6期13卷 619-620页

作者：兰德辉张建第三军医大学成都军医学院47医院内二科成都610500

目的 :探讨恶性贫血的诊断与鉴别诊断要点。方法 :对 14例恶性贫血患者的临床表现、实验室检查资料进行综合分析 ,并对其中 11例患者的误诊原因进行总结分析 ,全部患者均采用维生素B12 肌注治疗。结果 :14例患者全部治愈 ,远期疗效好。... 详细信息

目的 :探讨恶性贫血的诊断与鉴别诊断要点。方法 :对 14例恶性贫血患者的临床表现、实验室检查资料进行综合分析 ,并对其中 11例患者的误诊原因进行总结分析 ,全部患者均采用维生素B12 肌注治疗。结果 :14例患者全部治愈 ,远期疗效好。结论 :贫血合并神经系统损害 ,应高度怀疑恶性贫血的可能 ,应作血象、骨髓、胃镜、血清维生素B12 测定等检查 ,以确定诊断。并应与再障、急性白血病中的m6型、阵发性睡眠性血红蛋白病。

关键词：恶性贫血误诊诊断神经系统临床资料治疗

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