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The effects of oil droplet size and agar concentration on gel strength and microstructure of emulsion gels were investigated by compression test and cryoscanning electron microscope (Cryo-SEM). At all agar concentrations, the compressive stress values of emulsion gels were lower than those of the oil-free gels. Compressive stress and energy were significantly affected by oil droplet size and agar concentration, but compressive strain was not. SEM observation revealed that the overall volume of void spaces decreased and strand compactness increased with increasing agar concentration. Gels containing oil droplets had some void spaces between the gel network and the oil droplets. The strands of emulsion gels did not cover the oil globules completely, a phenomenon which was also observed for the gel with high agar concentration.  相似文献   
2.
A series of lead titanates containing lattice defects was prepared and characterized in terms of inhomogeneously distributed vacancies, □Pb and □O•. The tetragonal lattice strain and the Curie temperature varied as functions of the Pb or O deficiency in the crystals. The tetragonal strain for these crystals decreased slowly with increasing temperature as the Curie temperature was approached. The phase transition, which extends over a temperature interval, is interpreted according to a model in which microregions in the crystal differ in composition and therefore have different Curie temperatures.  相似文献   
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Abstract

Causality in changing natural systems can be seen to involve all four Aristotelian causal categories—material, efficient, formal and final. Final causality of materialistic origin can be found in the need to maintain energy flow continuity within dissipative systems. Each interacting dissipative system acts finalistically so as to attract needed energy. In so acting, it continually disturbs its neighborhood by generating potential energy flow disruptions as results of its activities. Final causality based, in this way, on the energy requirements of dissipative systems will generate formal causes as well. In contrast, the emergence of formal causes in mechanistic systems driven solely by efficient causes is extremely unlikely. We suggest viewing the subordination of phenotypic dissipative systems by genotypic counterparts as an historical example of the emergence of formal causes out of the material necessity of maintaining flow continuity. Functional separation between genotypic and phenotypic dissipative systems can occur if the energies to be dissipated are localized, as is the chemical binding energy of molecules with respect to biological functions at a higher scalar level.  相似文献   
4.
The characteristics of β-galactosidase from Bacillus circulans, and its suitability for hydrolysis of milk lactose were compared with those of Escherichia coli and Kluyveromyces lactis enzymes. Enzyme activity of β-galactosidase from B. circulans was not affected by major cations and proteins present in skim milk, whereas milk proteins and sodium and calcium ions decreased the activity of the enzymes from E. coli and K. lactis. The enzyme from B. circulans produced less oligosaccharides than E. coli and K. lactis during hydrolysis of lactose in skim milk at different lactose concentrations. Oligosaccharides produced by the enzyme from B. circulans disappeared almost completely at the latter stage of hydrolysis, while a large amount of oligosaccharides were still detected even at 98% conversion of lactose with enzymes from E. coli and K. lactis.  相似文献   
5.
Surface wave plasma(SWP) is a kind of low temperature plasma which can be utilized for material development.In this research,argon and oxygen were used as a working gas for an SWP experiment and the influence of the plasma irradiation on a copper surface was examined.Particular,relation between the spatial characteristics of SWP and wetting characteristics was examined.As a result,it was found that spatial characteristics of the SWP affected the wetting characteristics and the oxidation characteristics.  相似文献   
6.
为了从钢铁中提取各种夹杂物颗粒,考察了采用无水电解质的恒电位和恒电流的提取方法。结果认为,4%的MS[4 % (V/V)甲基水杨酸-1 % (m/V) 水杨酸-1 %( m/V) 四甲基氯化铵-甲醇)和10%AA(10 %(V/V)乙酰丙酮-1 % (m/V)四甲基氯化铵-甲醇]电解质溶液适用于提取钢铁中夹杂物TiOx和TiAl2O5。尽管这些电解提取法可以提取化学性能不稳定的夹杂物颗粒,然而,因为对夹杂物的观察是在萃取完成后于一个滤膜中进行,因此无法确定金属中每种夹杂物的具体位置。为了确定金属中夹杂物的具体位置,将卤-醇的光蚀刻方法用于以Ti和Al除氧的钢样品表面附近出现的夹杂颗粒,使用扫描电子显微技术和俄歇电子能谱(AES)对精细夹杂物颗粒形貌、尺寸和元素的偏析进行评估,不过卤醇却和钢铁中的金属钛和金属铝发生还原反应。对微小夹杂物颗粒的成分的形态、分离进行估测,然后,使用一种低加速能-扫描电子显微技术和俄歇电子能谱(AES)对用聚焦离子束制备微小夹杂物颗粒截面上元素的微观偏析进行评定。在这些研究结果基础上讨论了多元夹杂物颗粒的形成机理。    相似文献   
7.
The kinetics of ice crystallization in various polymer solutions were studied by the thermal response method in a batch crystallizer. Polymers suppress the secondary nucleation of ice crystals, depending on the kinds of polymer and concentration. The decrease of the nucleation rate constant in polymer solutions was related to the increase of viscosity. The effects of polymers on the nucleation rate were also observed in solutions containing low molecular weight compounds.  相似文献   
8.
A Lamb wave device using a PbZrO3 abased piezoelectric ceramic substrate and its application to an oscillator are described. The Lamb wave device which is practically in single-mode operation uses the zeroth-order symmetrical (S0 ) mode. A delay line oscillator is composed of the S0 mode device, an amplifier and an electrically controllable phase shifter, whose oscillation frequency varies with the applied voltage. The oscillator has fine frequency modulation characteristics in a wide frequency range from DC to 100 kHz. The device performance is useful for FM signal processing or voltage sensing.  相似文献   
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