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金龟子绿僵菌深层培养产几丁质酶的研究 总被引:3,自引:0,他引:3
金龟子绿僵菌(Metarhiziumanisopliae)是一种重要的昆虫寄生真菌,从自然罹病死亡的金龟子体内分离到一株金龟子绿僵菌(Metarhiziumanisopliae)M-6。研究了该菌深层培养产几丁质酶的情况,几丁质酶合成的最佳碳源和诱导物为几丁质,在以0.5%(w/v)几丁质为碳源时,其产几丁质酶活达0.126IU?mL?1,在一定范围内增加培养基中几丁质浓度,葡萄糖浓度,微量元素盐浓度和碳氮比都能提高几丁质酶活。胆汁酸和吐温80作为表面活性剂能显著提高几丁质酶活。通过摇瓶试验得到优化培养基和培养条件。根据优化条件在摇瓶和3.7L发酵罐中分别进行产酶试验,实验结果表明,几丁质酶活分别达到0.231IU?mL?1和0.273IU?mL?1。最适反应温度为55℃,最适反应pH6.0,在45℃,pH3.0~9.5较为稳定。Zn2+、Ca2+、Ba2+和Mn2+离子对几丁质酶活性有明显的促进作用,而Hg2+、Co2+和Fe2+离子完全抑制几丁质酶的活性。 相似文献
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深海锰结核处理技术及其发展趋势 总被引:1,自引:0,他引:1
深海锰结核中含有大量金属元素,若开发得当将是一种宝贵的陆地金属矿产替代资源。对半个世纪以来国内外开展的深海锰结核主要处理技术及其发展趋势进行了介绍。现有火法技术较适于处理高品位矿,工艺流程相对较短,但能耗较高;湿法技术较适于处理低品位及复杂矿,能耗低,但流程相对较长;火湿联合技术适用于不同含量、不同类型矿,但仍存在流程长、能耗高的缺点。近年来众多学者对湿法还原浸出作了有益的尝试,开辟了新的思路。指出更加注重综合利用和环保要求,开展现场加工等是未来锰结核处理技术的发展趋势。 相似文献
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固态发酵中纤维素基质降解过程初步研究 总被引:7,自引:1,他引:7
利用斜卧青霉(Penicillium decumbens JUA10)对汽爆麦草和淀粉质的混合基质进行固态发酵,通过分析各种成份及酶活力变化,研究了各成份的降解速率,并探讨了纤维素、半纤维素降解与纤维素酶、半纤维素酶酶活力的关系. 纤维素基质固态发酵中木质纤维素的降解过程实际是同步糖化发酵过程,还原糖不会积累形成对纤维素酶、半纤维素酶的反馈抑制;纤维素降解与纤维素酶的酶活性、半纤维素的降解与半纤维素的酶活性不成正比. 木质纤维素的降解难主要是木质纤维素结构造成的. 半纤维素的降解甚至比纤维素降解更慢,淀粉容易降解,木质素几乎不降解. 相似文献
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A new process is developed by using compound Mn as intermediate to produce Cl2 from HCl, with the following steps. (1) HCl steam is decomposed by intermediate Mn2O3 to produce Cl2 and MnCl2 at 500 °C. (2) Produced MnCl2 is oxidized by water steam to produce MnO at 450 °C. (3) The MnO compound is oxidized by air to yield Mn2O3. The X-ray diffraction (XRD) crystallite characterization results indicate the high conversion in each step under the optimum experimental conditions. Long term experiments for continuous conversion of HCl to Cl2 by using Mn2O3 as intermediate in a fixed bed reactor indicate that over 90%of HCl could be converted to Cl2 on stream of 30 h. The production of Cl2 from HCl with Mn compound as an intermediate and atmospheric steam is a feasible and recyclable process. 相似文献
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一种新的芒硝制碱法实验室研究 总被引:1,自引:0,他引:1
The purpose of this work is to find a new way for utilizing the rich sodium sulfate resource to produce soda ash. A novel process is proposed which uses aqueous dichromate solution as working medium through decomposition of calcium carbonate in aqueous sodium dichromate, complex decomposition of aqueous sodium sulfate and calcium chromate, regeneration of sodium dichromate and production of sodium bicarbonate from carbonation of aqueous sodium chromate solution, processing and utilization of byproduct calcium sulfate, and production of sodium carbonate from sodium bicarbonate. The process has the features of less corrosion and pollution and low energy consumption. 相似文献
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A stochastic approach,namely,Monte Carlo method with“tree structure pattern”has been adopted tosimulate the random backrnixing,residence time,reaction and dynamics of solid particles with size distribu-tion and with complex reaction in a complex flow system.Turbulence of particles in reactor system is simu-lated by stochastic tree pattern which is shown by pseudo-random number series picked from a uniformlydistributed set of numbers between zero and one.A Monte Carlo procedure is employed to model the par-ticles’ stochastic residence time,random flow and reaction with fluid.A large number of discrete bundlesof particles have been simulated and followed.Statistic results of all particles in the last information representthe solution to the problem under steady state of flow.The approach has a simple physical concept and simulation procedure.All calculation has been carriedout easily with a computer.For simple reaction system,results are in good agreement with those obtainedfrom the known approach and experiments.The method could provide a new kind of technique for simu-lating the behavior of particles in a continuous flow reactor. 相似文献
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