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1.
合成了4-氨基-3-苯基-5-巯基-1,2,4-三氮唑,并与乙酰二茂铁反应,制备了二茂铁基的4-氨基-3-苯基-5-巯基-1,2,4-三氮唑Schiff碱,并以此席夫碱作为新型配体,研究了其与过渡金属Cd的配位作用,全部产物用IR进行了表征。  相似文献   

2.
本文合成了3-巯基-5-羟基-6-甲基-1,2,4-三嗪和3-巯基-5,6-二甲基-1,2,4-三嗪,通过熔点和红外光谱确认了这些化合物。  相似文献   

3.
介绍了2,4-二硝基苯胺、2,6-二氯-4-硝基苯胺、2-氰基-4-硝基苯胺、2,4-二硝基-6-溴苯胺、2,6-二溴-4-硝基苯胺、2-氯-4-硝基苯胺、2,4-二硝基-6-氯苯胺七种弱碱碱性芳胺重氮盐固体的制备方法,并对其稳定机理进行了探讨。对制备得到的各重氮盐固体进行了热重分析,得到了它们各自的热分解温度,为该类芳胺在溶剂中进行重氮化反应制备重氮盐固体,提供了有力的数据支撑。  相似文献   

4.
本文阐述了1,2-萘醌-2-重氮基-5-磺酰氯的生产和废水处理,并通过络合萃取法进行废水处理,回收了原料1,2-萘醌-2-重氮基-5-磺酸钠。  相似文献   

5.
以1-羟基-2-萘甲酸与2-甲氧基萘为起始原料通过多步反应合成了标题化合物。首先将1-羟基-2-萘甲酸转化为1-(-)-薄荷氧基-2-萘甲酸-(-)-薄荷酯,再将2-甲氧基萘转化为1-溴-2-甲氧基萘,1-溴-2-甲氧基萘的格氏试剂与酯反应得到(S)-2'-甲氧基-1,1'-联萘-2-甲酸-(-)-薄荷酯。该薄荷酯再经还原反应、氧化反应、加成反应、氧化反应得到标题化合物。对各步反应的实验条件进行了适当改进,找到了较好的合成条件,并用1HNMR和13CNMR对各步产物进行了表征。  相似文献   

6.
以2-氯-4-氟-5-硝基苯酚为起始原料合成了28个1-杂环基-2-氟-4-氯-5-炔丙氧基苯类化合物,并对其进行了抑制苘麻生长的活性测试,总结了构效关系.发现2-(2-氟-4-氯-5-炔丙氧基苯基)-4,5,6,7-四氢异吲哚-1,3(2H)-二酮、2-(2-氟-4-氯-5-炔丙氧基苯基)-四氢咪唑并[1,5-a]吡...  相似文献   

7.
在传统异戊二烯氯化法制备异戊烯醇的工艺基础上,通过向氯代反应中加入一定量的2-甲基-3-丁烯-2-醇,部分2-甲基-3-丁烯-2-醇和浓盐酸反应生成3-氯-3-甲基-1-丁烯,有效地抑制了异戊二烯和浓盐酸反应过程中3-氯-3-甲基-1-丁烯的生成,异戊烯醇的总收率提高了约10%.此外,还对氯化、酯化和水解反应进行了优化...  相似文献   

8.
以1-(3,5-二硝基吡唑-4-基)-5-氨基-3-硝基-1,2,4-三唑的钾盐(KCPT)为原料,在酸性条件下用高锰酸钾氧化,一步得到(E)-1,2-双(1-(3,5-二硝基吡唑-4-基)-3-硝基-1,2,4-三唑-5-基)偶氮化合物(HDCPT)。收率由50.6%提高至84.5%,提高了合成过程的安全性,降低了成本。采用红外、质谱与核磁表征了产物的结构。  相似文献   

9.
本文对替米沙坦的合成工艺进行了优化研究,确定了以2-正丙基-4-甲基-6-(1-甲基-苯并咪唑-2-基)-苯并咪唑为起始原料,经缩合、水解两步反应即合成了替米沙坦,总收率为68%。该方法提高了反应收率,简化了反应操作,降低了成本,便于工业化生产。  相似文献   

10.
研究了根据酮麝香、1,3-二甲基-2,4-二硝基-5-叔丁基苯晶体生长速度的不同,从对二者均达到饱和的溶液中分离得到1,3-二甲基-2,4-二硝基-5-叔丁基苯晶体的过程,计算了晶体生长速度并进行了实验验证。  相似文献   

11.
民用工业中复合材料桁架的应用和发展   总被引:1,自引:0,他引:1  
本文叙述了复合材料桁架的构造、分类和计算方法,突出了复合材料桁架的优越性能和在民用工业中的应用前景;在分析大量文献资料的基础上阐述复合材料桁架杆件的多种加工工艺,并比较不同截面形式对杆件性能的影响;探讨复合材料杆件的破坏机理和分析方法,介绍节点的类型和各自的特点,提出节点及连接部位存在的关键问题;根据国内外复合材料桁架的研究和应用现状,阐述了复合材料桁架的性能和不同的设计方法,总结归纳影响复合材料桁架性能的关键因素和设计中存在的一些问题,并提出改进杆件设计、节点设计和优化复合材料桁架的建议。  相似文献   

12.
马润梅  赵祥  李双喜  刘兴华  许灿 《化工学报》2021,72(11):5726-5737
在含有颗粒介质的工作环境中下,硬质材料配对机械密封环的热力耦合变形和摩擦磨损对机械密封的泄漏和使用寿命起着至关重要的作用。考虑动静环和颗粒介质的摩擦,试验测定了摩擦系数,建立了动静环热力耦合的有限元计算模型,研究了WC-Co硬质合金和无压烧结碳化硅(SSiC)陶瓷两种硬质材料密封的温度场和端面变形规律,分析了不同工况下的密封间隙变化规律。试验测试分析了密封环温度、磨损前后的泄漏及表面粗糙度,讨论了端面的磨损机理,验证了计算模型的准确性。结果表明:考虑动环磨粒摩擦热的有限元模型能准确地预测密封的温度和端面变形;耦合作用下动静环端面呈现外径脱离、内径贴合的变形,且变形差异程度随压差和转速的增大而加剧;变形导致端面磨痕分布不均匀,内径磨痕较严重。WC-Co硬质合金配对密封环的端面变形小、泄漏量小,高硬度WC颗粒对Co基体能产生很好的“阴影效应”,具有良好的耐磨粒磨损性能。SSiC陶瓷材料韧性差,易产生片状磨屑,形成过渡型磨粒磨损,材料耐磨性较差,泄漏量增加明显。在磨粒工况下,WC-Co硬质合金机械密封具有泄漏小、耐磨性强的特点。研究结果为颗粒介质中机械密封的材料应用及设计优化提供了参考。  相似文献   

13.
Technology and colour are viewed as interfaces between the environment, humans and human activity. Examples are provided of ways of facilitating and improving access to and use of colours by commercial users of colour coatings through improvements in the accuracy of measuring and displaying colour. By analogy, the task of providing effective interfaces within the coatings industry, between the coatings industry and the environment and between the coatings industry and the public and political domain are discussed. Examples of information shortfalls are cited to illustrate how distortions arise. Examples of more effective, integrated technological, organisational and political interfacing are culled from the author's experiences.  相似文献   

14.
木质纤维生物质资源是重要的可再生生物质资源,主要包含纤维素、半纤维素和木质素。半纤维素含量仅次于纤维素,是一种丰富、可再生的植物资源,其可水解制备重要化学品以及改性制备多功能材料。本文综述了生物质半纤维素分子模拟应用研究进展,从半纤维素大分子形态及其与纤维素结合方式的分子模拟研究和半纤维素制备化学品及材料的分子模拟研究2个方面进行阐述,从模拟结果可以看出半纤维素在细胞壁中与纤维素和木质素的相互作用及其本身的大分子形态对木质纤维生物质三大素的提取利用具有显著影响。分子模拟有利于理解过程机理,对反应效率的提高具有重要理论指导意义。最后对分子模拟在半纤维素研究的发展应用进行了展望,指出目前半纤维素分子模拟的空白领域,主要包括半纤维素液化生产生物油、木糖异构化生产木酮糖、半纤维素与木质素之间的结合方式以及其他的半纤维素基材料等,这些有待进一步的探索与研究。  相似文献   

15.
在绿色化学理念的引导下,可生物降解膜材料受到了广泛的关注,有望成为传统分离膜材料的补充和替代品。本文首先分析了传统的不可降解分离膜材料的现状及问题,然后综述了当前较为热门的几种可生物降解膜材料,讨论了它们的发展状况,详细介绍了它们在膜相关领域中的应用,并针对它们的局限性做出了说明并提出了一些解决方案。随后,分析了可生物降解膜材料的生物降解机理,从分子结构角度对膜材料的可生物降解性进行了说明,这将有利于剖析膜材料生物降解的本质,进而平衡膜材料在使用中的稳定性和生物降解性。最后,文章对可生物降解膜材料在发展中遇到的问题进行了展望,并指出随着研究的不断深入,可生物降解膜材料具有广阔的前景和深远的现实意义。  相似文献   

16.
Effectiveness of lipase in detergency was studied using three test soils (lard, artificial sebum, and olive oil) on a woven cotton fabric. Distribution of oily soil on fabrics was determined for three different treatments (unwashed, washed with detergent without lipase, and washed with detergent plus lipase). Osmium tetroxide was used to label lipid soil for analysis in the scanning electron microscope. Both longitudinal and cross-sectional backscattered electron images for unwashed samples showed that soil was present on surfaces of the cotton fibers and in interfiber spaces of the yarn bundle. Lard soiled samples had large deposits on the fabric surfaces, while artificial sebum and olive oil appeared more uniformly distributed throughout the textile. Oil was deposited in the interfiber capillaries of the yarn bundle and in the crenulation, secondary walls, and lumen of the fibers. Energy dispersive X-ray microanalysis was used to determine relative concentrations of oil at selected morphological locations within the fiber structure and at the fiber surface. Soil distributions within the fibrous structures differed with type of soil and laundry treatment. Backscattered electron images dramatically demonstrated the effect of lipase on cleaning. After washing with detergent plus lipase, yarn surfaces had much less residual soil; residual soil that remained was in the irregularities of the cotton fiber surfaces. Concentrations of oil in the secondary walls, crenulations, lumen, and the fiber surfaces were lower after lipase treatment for all three soils. While washing with detergent removed soil from the yarn and fiber surfaces and the crenulation of the cotton fiber, only the samples washed with detergent plus lipase had lower concentrations of soils within the secondary wall and lumen of the cotton fibers. Fabrics soiled with olive oil and washed with detergent plus lipase had the lowest concentrations of residual soil across the textile structure; the residual soil observed was mainly in the irregularities on the fiber surfaces.  相似文献   

17.
There is an increased demand for convenient foods including ready-to-eat and instant products. These products are desired with minimum concentration of synthetic chemicals. This creates challenges for the food industry and dryers manufactures to develop new technologies to process difficult-sensitive materials and to supply final products with high quality and improved properties. Fruits and vegetables are mainly composed of water, carbohydrates, proteins and lipids. Due to modification of chemical and physical bonds the compounds the material becomes viscous and sticky during processing. Conventional dryers have limitations in handling such sensitive materials. Heat pump dryers have been applied in the production of a diversity of ready-to-eat foods and dried instant products for the last five years at SINTEF-NTNU. Besides being energetically efficient and environmentally friendly, the heat pump drying technology provides a wide range of drying conditions as required to produce powders with improved characteristics. This work describes the new technologies and processing line for the production of instant foods as well as the measurements on the properties and quality attributes for raw, intermediate and final instant products.  相似文献   

18.
The effect of various pretreatments on drying kinetics as well as quality parameters of selected vegetables and fruits was studied experimentally in a convective dryer. The pretreatments tested include application of pinholes and drilled holes of different diameters and densities, blanching and freezing. Potato, cassava, dragon fruit and red chilli were used as the sample drying materials. As expected, increase of the diameter and density of the holes under fixed drying conditions increased the drying rate. Samples with drilled holes showed better drying performance than those with pinholes. The improvement of the drying rate was found to be dependent on the physical properties and the initial moisture content of the material. Results show that the drying performance of the products that possess a skin of low moisture diffusivity, such as chilli, can be improved significantly by blanching and making perforations in the skin. Overall changes of color and volume shrinkage during drying of the samples with and without holes were similar. The effect of different modes of heat input, such as convection, conduction and radiation, on the drying performance of the treated samples was also experimentally investigated. On-off type controllers were used to regulate the power of the heaters and maintain the product temperature within a range of pre-set values. Convection combined with radiation displayed the highest drying rate.  相似文献   

19.
为了同时分离甘草中有表面活性的甘草酸和黄芩中无表面活性的黄芩苷,开发了甘草配伍黄芩泡沫分离工艺。通过荧光光谱、紫外吸收光谱和红外吸收光谱分析表明,甘草酸与黄芩苷存在相互作用,并且甘草黄芩配伍强化了甘草酸和黄芩苷的提取。以甘草酸和黄芩苷的富集比和回收率为评价指标,当温度为40℃、气体体积流量为100 ml·min-1、甘草酸初始浓度为0.2 g·L-1、甘草黄芩质量比为3:1时,获得甘草酸的富集比和回收率分别为11.0和73.5%,黄芩苷的富集比和回收率分别为5.8和38.5%。通过甘草与黄芩配伍,利用泡沫分离获得黄芩中的黄芩苷。同时,与单独泡沫分离甘草中甘草酸相比,甘草酸的富集比提高了194.9%,回收率提高了23.3%。因此,甘草配伍黄芩能有效泡沫分离甘草酸和黄芩苷。  相似文献   

20.
The physical and hence mechanical properties of carbon fiber reinforced epoxy resin are affected by the curing conditions used in their manufacture. The relationship between the cure temperature and pressure and the density, fiber volume fraction, and the void content of cured laminates, was investigated. For the unidirectional 914C prepreg material used, an optimum cure temperature was found which gave maximum fiber volume fraction and composite density, and minimum void content. This behavior is related in the paper to resin flow and cure characteristics. A linear relationship between cure pressure and fiber volume fraction is reported and explained by reference to the void content of the laminates. It is concluded that in-house trials are required to determine the optimum size of the processing window for specific systems and components.  相似文献   

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