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31.
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本文叙述了近十年来我国对正烷烃酵母研究的进展。我们用的菌种是热带假丝酵母Y-17,本所实验厂的生产规模是年产一百吨酵母。发酵罐为6米~3的内或外循环空气提升式,两级连续发酵,50%废水循环利用。生产能力为2克/升·小时。酵母产品的化学分析,包括蛋白质、氨基酸、脂肪、核酸、维生素等,都证明该产品为一优良蛋白饲料。有毒物质含量(如苯骈(a)芘、重金属)符合国际标准。动物试验(包括用大白鼠、鸡、猪的营养试验,慢性毒性试验,传代试验)证明该正烷烃酵母为安全可靠的优良饲料。我们也研究了酵母的核酸和脂肪的综合利用、并筛选了一株高产新菌株球拟嗜烷烃酵母(新种)4B-2,使生产能力提高至2.8克/升·小时。 相似文献
33.
采用硝酸镍和硝酸铈水溶液共浸渍薄水铝石制备了 Ni/CeO2/Al2O3 催化剂, 并将其用于低水碳摩尔比条件下商用液化石油气 (LPG) 预重整反应. 考察了 Ni 含量和反应温度对催化剂性能的影响. 结果表明, 在 300~400 oC 和水碳摩尔比为 1.0 的条件下, 该催化剂具有很高的催化 LPG 预重整反应活性. 15%Ni/CeO2/Al2O3 催化剂在 350 oC, 3 000 ml/(g•h) 和水碳摩尔比 1.0 的条件下, 反应 105 h 后 LPG 转化率和产气组成均保持不变, 表现出较高的稳定性. 反应后催化剂表面没有明显的积炭. 相似文献
34.
A numerical study of hydrogen-enhanced liquefied petroleum gas (LPG) + air flames was presented. The variations of the adiabatic burning velocity in different conditions of combustion (?=0.7-1.4) were studied extensively. The hydrogen content in the fuel was varied from 0% to 45% and the dilution factor was from 21% to 16%. Since the major components of LPG are butane and propane, an appropriate chemical kinetic model must be chosen to solve the chemical reaction of C3 and C4 species. Validation of the chemical kinetic model against the fundamental combustion data was performed to insure accuracy. In addition, independent simulations were conducted in the opposed-jet, symmetric, twin-flame configuration. The effects of fluid mechanics, as manifested by the induced strain rate, were also considered. The effects of extinction strain rate on flame temperature and the flammability limits were calculated and the results showed that hydrogen-enhanced LPG/air premixed flames were more stable at high flame strain. The lean flammability limits were extended by the H2 addition. 相似文献
35.
36.
The direct injection of CO2 into the deep ocean is one of the feasible ways for the mitigation of the global warming, although there is a concern about its environmental impact near the injection point. To minimize its biological impact, it is necessary to make CO2 disperse as quickly as possible, and it is said that injection with a pipe towed by a moving ship is effective for this purpose. Because the injection ship moves over a spatial scale of O(102km), a mesoscale model is necessary to analyse the dispersion of CO2. At the same time, since it is important to investigate high CO2 concentration near the injection point, a small‐scale model is also required. Therefore, in this study, a numerical model was developed to analyse CO2 dispersion in the deep ocean by using a fixed mesoscale and a moving small‐scale grid systems, the latter of which is nested and moves in the former along the trajectory of the moving ship. To overcome the artificial diffusion of mass concentration at the interface of the two different grid systems and to keep its spatial accuracy almost the same as that in the small‐scale, a particle Laplacian method was adopted and newly modified for anisotropic diffusion in the ocean. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
37.
Ocean internal waves interpreted as oscillation travelling waves in consideration of ocean dissipation 下载免费PDF全文
Most studies of the synthetic aperture radar remote sensing of ocean internal waves are based on the solitary wave solutions of the Korteweg-de Vries (KdV) equation, and the dissipative term in the KdV equation is not taken into account. However, the dissipative term is very important, both in the synthetic aperture radar images and in ocean models. In this paper, the traveling-wave structure to characterize the ocean internal wave phenomenon is modeled, the results of numerical experiments are advanced, and a theoretical hypothesis of the traveling wave to retrieve the ocean internal wave parameters in the synthetic aperture radar images is introduced. 相似文献
38.
杨村煤与石油渣油共处理高温缩聚反应特性的研究 总被引:4,自引:0,他引:4
用GJ-2型微型反应釜研究了兖州杨村煤与石油渣油在470℃时共处理反应的特性,结果表明,杨树煤和石油渣油在高温下进行共处理反应时,宏观表现是缩聚反应占主导地位,程序升温可提高煤的转化率,添加四氢萘到石油渣油中可抑制缩聚反应,而且添加量越大,抑制效果越明显,煤液化产物的重新加氢也会发生一定的缩聚反应,可产生微量结渣。 相似文献
39.
F. Crisciani R. Purini 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,31(4):571-575
The present note deals with Munk's ocean model and proposes an alternative approach to find its solution, with special regard
to the western boundary layer. We introduce a suitable “distance” between the related Sverdrup streamfunction and all the
admissible streamfunctions which are valid in the western boundary layer. We prove that such distance has a minimum that singles
out a unique solution. Unlike the traditional method, this procedure works without assuming a priori any dynamic boundary
condition.
Received 16 July 2002 Published online 6 March 2003
RID="a"
ID="a"e-mail: fulcri@itt.ts.cnr.it 相似文献
40.
散射通信在海洋石油开采中的应用研究 总被引:1,自引:0,他引:1
对流层散射通信凭借其单跳跨距大、传输容量大、架设方便、经济实用等优势在海洋石油通信中得到青睐。首先分析了散射通信技术在海洋石油开采应用的优越性,然后介绍了海洋石油散射通信设备的组成及关键技术指标,最后分析并给出了散射设备采用的关键技术。 相似文献