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91.
Six materials (stainless steel, nickel-base alloy, titanium, chromium, nickel and admiralty brass) are tested in chemical and biochemical synthetic seawaters. The biochemical seawater contains enzymes catalyzing oxidation of glucose (glucose oxidase), simulating the action of natural biofilms. The evolutions of free corrosion potential (Ecor) versus time, and of cathodic and anodic reactions are compared with those obtained in natural seawater. Then, electrochemical behavior is related to semi-conducting properties of passive films. When glucose oxidase is present, increase of Ecor versus time is only reported for materials presenting a n-type semi-conductor passive film, and whose cathodic reaction current is increased. On the contrary, when passive layers are p-type semi-conductors, cathodic and anodic reactions are increased, and lead to a global Ecor constant with time of immersion. It appears that interaction between bacteria, medium and materials includes evolution of semi-conducting properties of passive layers. 相似文献
92.
多孔粒状铵油炸药在边坡预裂爆破中的应用 总被引:3,自引:0,他引:3
通过工程实践,介绍了利用多孔粒状铵油炸药进行边坡预裂爆破的设计原理及施工工艺。该技术能确保预裂爆破质量。简化施工工序,大幅度降低爆破成本。技术经济指标优越。 相似文献
93.
驻极体声传感器及其储电材料的现状 总被引:1,自引:0,他引:1
综述了驻极体声传感器及其储电材料近年来的迅猛发展。传统的FEP(tetrafluoroethylene—hexa—fluoropropylene copolymer)极体电容式声传感器及以铁电聚合物PVDF(poly vinylidene fluoride)家族为芯片的声传感器和超声抉能器仍焕发着青春活力。Si基微型驻极体声传感器的理论和实验研究已经日趋成熟,而用空间电荷型多孔聚合物驻极体压电薄膜为芯片可望研制出新一代声电和电声传感器、压力传感器和驱动器。 相似文献
94.
Summary In flow through porous media, solutions of poly(ethylene oxide) (PEO) exhibit extension thickening, whereas hydroxypropyl
guar (HPG) solutions are shear-thinning at high concentrations. The results show that the extension-thickening exhibited by
PEO solutions becomes less critical with increasing flow rate as the concentration of HPG in the solution is increased. At
high concentrations of HPG, the presence of PEO inhibits the shear-thinning behaviour, without increasing the apparent viscosity
of the solution. The presence of HPG reduces the rate and extent of degradation of PEO in the flowing solution. 相似文献
95.
96.
聚丙烯表面改性及与涂料的粘结 总被引:3,自引:2,他引:1
刘景江 《高分子材料科学与工程》1992,8(5):1-5
讨论了聚丙烯制品喷涂着色的优点及影响聚丙烯制品与涂料之间粘结强度的各种因素。综述和评价了对聚丙烯进行表面改性的必要性及各种表面改性方法。 相似文献
97.
Thermal Shock Behavior of Porous Silicon Carbide Ceramics 总被引:1,自引:0,他引:1
Using the water-quenching technique, the thermal shock behavior of porous silicon carbide (SiC) ceramics was evaluated as a function of quenching temperature, quenching cycles, and specimen thickness. It is shown that the residual strength of the quenched specimens decreases gradually with increases in the quenching temperature and specimen thickness. Moreover, it was found that the fracture strength of the quenched specimens was not affected by the increase of quenching cycles. This suggests a potential advantage of porous SiC ceramics for cyclic thermal-shock applications. 相似文献
98.
阐述了用AutoLisp程序模拟塑料熔体在2层复合膜机头内的流动情况,并介绍了复合膜机头的内部结构。 相似文献
99.
100.
Donghua Zhang 《应用聚合物科学杂志》2006,101(6):4372-4377
Polyaniline (PANI) was synthesized by chemical oxidative polymerization of aniline (ANI) in the presence of alumina (Al2O3) particles. The polymerization of ANI occurred preferentially on the surfaces of the particles, resulting core–shell structured alumina–polyaniline (Al2O3‐PANI) particles. Morphology examination showed that with decreasing of the weight ratio of Al2O3/ANI in the reactants, the thickness of the PANI layer increased and changed from an even surface morphology to a particulate morphology. UV–vis and Fourier transformed infrared (FTIR) spectra indicated that there is no chemical interaction between the PANI layer and the Al2O3 surfaces. The PANI layer adhered well to the particles and can be used as anticorrosive fillers for polymer coatings. Enhanced corrosion protection performance was achieved for the emeraldine base (EB) form of PANI deposited Al2O3 particles (Al2O3‐EB) filled epoxy coating on carbon steel in 3.0 wt % aqueous NaCl solution. The particles demonstrate both excellent corrosion protection performance and lower cost, which will be of great importance in practical applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4372–4377, 2006 相似文献