Surface morphologies of aluminum films on silicone oil surfaces

The surface morphology and growth mechanism of an aluminum film system deposited on silicone oil surfaces by a vapor depositing method was investigated by scanning electron microscopy. It was found that the perpendicular fluctuation of the film's bottom surface was more remarkable than that of the film's top surface. Near the joint between the film on the silicone oil substrate and the film on the silicon wafer surface on which the silicone oil substrate rested, was a naturally formed anomalous wedge-shaped wrinkly structure with slopes of 10⁻⁴–10⁻⁵ rad, whose growth mechanism could be interpreted under the assumption of the thermal expansion behavior of the liquid substrates. Project supported by NSFC (No. 19874016) and the Special Fund of Zhejiang Provincial Natural Science Foundation for Young Scientists (Grant No. 1997RC9603).     

Preparation of Ultrafine γ-Al_2O_3 Particles in Non-ionic Water in Oil Microemulsions

1IntroductionThesynthesisofultrafineparticles(UFPs)isofincreasingscientificandtechnicalinterest.Thesmallsizeofthesepal-tidesendowsthemwithunusualstlvctural,electronic,optical,magneticandchemicalproperties,leadingtomanyimportalapplicationssuchascatalysts,e…     

Study on coagulation property of metal-polysilicate coagulants in low turbidity water treatment

INTRODUCTION Coagulation-flocculation is a major step inthe potable water treatment for removal of colloi-dal impurity. Due to the increase of water pollu-tion, the standards of drinking water supply andwastewater discharge are becoming more and morestringent, and chemical coagulants that are moreefficient in water treatment are more and moreurgently in demand. As well known, the residual Al in potablewater comes from three main sources: natural wa-ter-body, coagulants used in…     

Sintering and microstructure of silicon carbide ceramic with Y3Al5O12 added by sol-gel method

Silicon carbide (SIC) ceramic with YAG (Y3Al5O12) additive added by sol-gel method was liquid-phase sintered at different sintering temperatures, and the sintering mechanism and microstructural characteristics of resulting silicon carbide ceramics were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and elemental distribution of surface (EDS). YAG (yttrium aluminum garnet) phase formed before the sintering and its uniform distribution in the SiC/YAG composite powder decreased the sintering temperature and improved the densification of SiC ceramic. The suitable sintering temperature was 1860 ℃ with the specimen sintered at this temperature having superior sintering and mechanical properties, smaller crystal size and fewer microstructure defects. Three characteristics of improved toughness of SiC ceramic with YAG added by sol-gel method were microstructural densification, main-crack deflection and crystal ‘bridging‘.     

壳聚糖提高医用氢氧化铝的抗酸性

以模拟胃酸研究了壳聚糖／氢氧化铝混合物微粒在体外的抗酸性．结果表明，壳聚精不仅能改善医用氢氧化铝对酸的中和速率，提高中和酸的能力，更可抑制氢氧化铝与碱的反应．故可望用壳聚糖／氢氧化铝制备抗胃酸复合制剂．     

A perspective of microplasma oxidation （MPO） and vapor deposition coatings in surface engineering of aluminum alloys

IntroductionInrecentyears,improvingthewearlifeofAl-basedalloyscomponentsinheavysurfacecontactconditionsbytheapplicationofmicroplasmaoxidation(MPO)coatingshasprovensuccessfulundertechnicalandeconomicconsideration.MPOtechnologyhasrecentlybeentakenasarapid,novelandeffectivemeanstoprovidethickceramiccoatingswithexcellenthardnessandload-bearingcapacityforlightalloymaterials,particularlyaluminumalloys[1].TheMPO,alsocalledplasmaelectrolyticoxidation(PEO),isanadvancedtechnologyforroutineanodizing…     

利用铝厂污泥研制陶瓷无光釉

本文利用铝型材厂污泥为原料,配制陶瓷无光釉,属固体废弃物综合开发利用项目。实验结果表明：污泥用量可高达10％-20wt％,配方中随着污泥含量的增加,釉面由光泽逐渐地转变到亚光直至无光。为使组成稳定,防止釉面开裂,污泥必须先经过干燥、预烧后再投入使用,污泥的最佳预烧温度为1200℃。     

铝型材拉弯成形数值模拟及工艺优化

针对汽车行李架铝型材拉弯成型问题,运用ABAQUS 有限元分析软件,建立型材拉弯成形过程的有限元模型,通过对A6043 铝型材结构件进行拉弯成形正交数值试验,研究预拉量、包覆拉伸量、补拉量和摩擦系数等拉弯成形关键工艺参数对型材回弹量的影响规律,结果表明:在一定拉伸范围内,回弹量随预拉量、包覆拉伸量、补拉量的增大而减少,随摩擦系数的增大先减小后增大?工艺参数中包覆拉伸量对回弹结果的影响最大,达到3%,回弹量趋于稳定?当预拉量为1%、包覆拉伸量为3%、补拉量为1%、摩擦系数为0.1 的工艺参数下,不规则铝型材汽车行李架拉弯成形后的回弹量最小。     

Preparation of ultrafine γ-Al2O3 particles in non-ionic water in oil microemulsions

Ultrafine γ-Al₂O₃ particles are synthesized in Triton X-100/n-hexanol/cyclohexane/water water in oil(w/o) microemulsion by mixing two separately prepared microemulsions containing Al(NO)₃ and (NH₄)₂CO₃ respectively. The ultrafine Al₂O₃ particles are characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD) and their size and distribution are measured. The effects of water, surfactant and reactant concentrations on the particle size and distribution are studied. The results show that the particle size and distribution can be changed by varying the preparation conditions, and the size of the microemulsion droplets has a controlling effect on the size of the particles. A possible mechanism of ultrafine particles (UFPs) prepared by microemulsions is proposed.     

无水三氯化铝催化合成环己烯

以无水三氯化铝作催化剂,对环己醇脱水制备环己烯的反应进行研究.考察了催化剂用量、反应温度、反应时间等因素对脱水反应的影响,得出了其最佳的反应条件:催化剂用量为环己醇质量的13.3%,反应时间80 m in,油浴温度200~210℃.在此条件下,产品收率可达87.8%,纯度达98.4%.