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171.
本文对酿造工业使用的产葡萄糖淀粉酶的几种野生和诱变根霉及黑曲霉菌种的保藏方法进行了探讨。研究表明:经7年保存的麦麸曲室温和低温(4℃)、马铃薯葡萄糖琼脂斜面石腊油封存低温保藏方法保藏菌种全部存活,室温保藏菌种糖化酶活力显著降低,而低温保藏菌种糖化酶活力虽也降低,但仍不失为工业上菌种保藏的一种有效方法。 相似文献
172.
根据热分析谱图峰顶的数学特征与Coats-Redfern方程,推得在一定实验条件下,在系列相关反应中,若峰顶温度相接近,则各反应的表观活化能E与指前因子A之间存在着有动力学意义的补偿效应,即lnA=aE+b。并经系列含水硫酸盐脱水反应实验验证。 相似文献
173.
Untraceable partially blind signature based on DLOG problem 总被引:1,自引:0,他引:1
This paper proposes a new untraceable Partially Blind Signature scheme which is a cross between the traditional signature scheme and the blind signature scheme. In this proposed scheme, the message M that the signer signed can be divided into two parts. The first part can be known to the signer (like that in the traditional signature scheme) while the other part cannot be known to the signer (like that in the blind signature scheme). After having signed M, the signer cannot determine if he has made the signature of M except through the part that he knows. We draw ideas from Brands‘ “Restricted Blind Signature“ to solve the Untraceable Partially Blind Signature problem. Our scheme is a probabilistic signature scheme and the security of our Untraceable Partially Blind Signature scheme relies on the difficulty of computing discrete logarithm. 相似文献
174.
With the explosion of services in grid environment, it's necessary to develop a mechanism which has the ability of discovering suitable grid services efficiently. This paper attempts to establish a layered resource management model based on the locality principle which classifies services into different domains and virtual organizations (VOs) according to their shared purposes. We propose an ontologybased search method applying the ontology theory for characterizing semantic information. In addition, we extend the UD- D1 in querying, storing, and so on. Simulation experiments have shown that our mechanism achieves higher performance in precision, recall and query response time. 相似文献
175.
176.
利用山路引理证明一类拟线性退化椭圆型方程的解的存在性 ,并利用 Pohozeav恒等式证明 ,当 q+1 >p(n+α) / (n+α- p)时 ,该方程不存在非平凡解 相似文献
177.
Effects of Na<Subscript>2</Subscript>SO<Subscript>4</Subscript> on iron and nickel reduction in a high-iron and low-nickel laterite ore
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This study investigates the reactions of Na2SO4 and its effects on iron and nickel reduction in the roasting of a high-iron and low-nickel laterite ore through gas composition, X-ray diffraction, and scanning electron microscope analyses. Results showed that a reduction reaction of Na2SO4 to SO2 was performed with roasting up to 600℃. However, no clear influence on iron and nickel reductions appeared, because only a small amount of Na2SO4 reacted to produce SO2. Na2SO4 reacted completely at 1000℃, mainly producing troilite and nepheline, which remarkably improves selective reduction of nickel. Furthermore, the production of low-melting-point minerals, including troilite and nepheline, accelerated nickel reduction and delayed iron reduction, which is attributed to the concurrent production of magnesium magnetite, whose structure is more stable than the structure of magnetite. Reduction reactions of Na2SO4 resulted in weakening of the reduction atmosphere, and the main product of Na2SO4 changed and delayed the reduction of iron. Eventually, iron metallization was effectively controlled during laterite ore reduction roasting, leading to iron mainly being found in wustite and high iron-containing olivine. 相似文献
178.
马铃薯酪氨酸酶的部分纯化及理化性质的研究 总被引:8,自引:0,他引:8
马铃薯酪氨酸经粗提、丙酮沉淀和酸铵分级后,得到了纯化1.8倍,活力回收42.5%,比活力为49.7U/mg蛋白的部分纯化酶,并对其理化性质进行了研究。结果表明,以多巴为底物,酶的Km为5.7mmol/L,Vm为16.2μmol/L?min,最适PH为8.2,最适温度为40℃,HSO^-3F^-、苯甲酸、叠氮化钠、过氧化氢为其抑制剂,Vc、苯肼等对该酶的半抑制浓度为μmol/L水平。Cu^2+在低浓 相似文献
179.
该文对一株巨大芽孢杆菌产胞外青霉素酰化酶的发酵条件下进行了初步研究。不同的氮源及装液量和发酵时间产酶均有影响。该菌株在27-28℃180r/min,初始PH8.0,苯乙酸浓度0.6%的最佳发酵条件下发酵60h左右,青霉素酰化酶活力可达500-700U/100ml。 相似文献
180.
本文通过建筑内部给水系统的能耗构成分析,给出了能谱图的绘制方法及其在高层建筑分区给水系统节能上的应用. 相似文献