共查询到20条相似文献,搜索用时 156 毫秒
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介绍了标题化合物的合成方法。以柠康酸酐和水合肼为起始原料,经环合、氯代、水合肼取代、脱肼基共4步反应合成了目标化合物,并经1HNMR等对其结构进行了表征。本合成反应条件温和、原料易得、操作简便,适合于工业化生产。反应总收率为30%。 相似文献
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以对二氯苯为原料,经硝化、水合肼催化还原、Bamberger重排等反应合成了2,5-二氯-4-氨基苯酚;并对水合肼催化还原和Bamberger重排反应的条件进行了优化。在优化的条件下,2,5-二氯苯胲的收率达96.1%,2,5-二氯-4-氨基苯酚的收率达53.1%。该合成工艺具有反应周期短、条件温和、收率高和后处理简单等优点,有产业化前景。 相似文献
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Selected fuel, oxidizer and simulant gels were prepared and rheologically characterized using a rotational rheometer. For fuel gelation both organic and inorganic gellants were utilized, whereas oxidizers and simulants were gelled with addition of silica and polysaccharides, respectively. The generalized Herschel‐Bulkley constitutive model was found to most adequately represent the gels studied. Hydrazine‐based fuels, gelled with polysaccharides, were characterized as shear‐thinning pseudoplastic fluids with low shear yield stress, whereas inhibited red‐fuming nitric acid (IRFNA) and hydrogen peroxide oxidizers, gelled with silica, were characterized as yield thixotropic fluids with significant shear yield stress. Creep tests were conducted on two rheological types of gels with different gellant content and the results were fitted by Burgers‐Kelvin viscoelastic constitutive model. The effect of temperature on the rheological properties of gel propellant simulants was also investigated. A general rheological classification of gel propellants and simulants is proposed. 相似文献
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目的:建立紫外可见分光光度法检测聚维酮K30中肼的方法。方法:样品中的肼与对二甲氨基苯甲醛作用,生成时二甲氧基苄连氮,在酸性条件下,形成醌式结构的黄色化合物,在457nm处有最大吸收,在测定范围内黄色深度与肼含量成正比,利用此原理,可以定量测量。结果:对同一样品进行多次检测,同时加入2μg肼做回收率实验,样品加标回收率在96.0%-97.5%之间,样品检测结果的相对标准偏差为3.7%(n=6)。结论:用紫外可见分光光度法检测聚维酮中的肼有较好的回收率和重现性,方法准确、简单、易行。 相似文献
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基于Aspen Plus用户模型的甲醇合成模拟及分析 总被引:1,自引:0,他引:1
对板间换热式甲醇合成塔建立了一维拟均相数学模型,并用四阶Runge-Kutta法求解其轴向温度与浓度分布。利用Aspen Plus中的User 2模块将其嵌入整个甲醇合成全流程进行模拟,并用取自工厂的实际数据进行验证,结果吻合良好。分析得到了原料气入口温度、操作压力、汽包压力及进料流量对反应器出口甲醇物质的量分数的影响,以及不同时期催化剂的活性分布及粗甲醇的产量分布,提出了在催化剂中后期应采取提高操作压力的措施来保证粗甲醇的产量。 相似文献
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David J. Matz William G. Guldemond Stuart L. Cooper 《Polymer Engineering and Science》1973,13(4):300-307
A modified Eyring rate expression based on an asymmetrical potential energy barrier is used to predict the onset of plastic yield in glassy polymers. Equations for the prediction of plastic yield delay times in creep and yield stresses in constant rate of strain testing are developed and compared to experimental data for samples of polycarbonate and polysulfone with various thermal histories. The two equations accurately fit the experimental results for a suitable choice of parameters. Parameters from the creep data can be used to predict yield stress values in constant rate of strain testing. Variation in simple thermal history changes the model parameters in a way that is qualitatively accounted for from a physical interpretation of the constants. 相似文献
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J.L. Feimer A.K. Jain R.R. Hudgins P.L. Silveston 《Chemical engineering science》1982,37(12):1797-1805
The kinetic adsorption/desorption or AD models used to predict product selectivities obtained through forced-feed concentration cycling have been re-examined. Selectivity improvement results from model structure and nonlinear rates of reaction. The relaxed-steady state bound to periodic operation was found to be predictable from steady state rates for the kinetic model used. Adsorption/desorption models predict no rate improvement for periodic operation. Also they fail to predict experimental observations that are now fairly extensive. 相似文献