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1.
基于利用厨余垃圾作为合成挥发性脂肪酸(VFAs)的原始基质,既可以增加厨余垃圾资源化利用新途径,又可以降低聚羟基脂肪酸酯(PHA)合成成本,有利于厨余垃圾合成PHA产业化发展的优势,概述了PHA的应用领域和类型,总结了厨余垃圾合成PHA工艺路线和PHA前体物(VFAs)合成阶段与PHA 合成阶段的内在合成机制,重点汇总了利用厨余垃圾合成VFAs过程和利用VFAs合成PHA过程的重要工艺参数。最后,对厨余垃圾合成PHA 研究方向进行了展望。  相似文献   

2.
邻苯二酚清洁合成方法的研究进展   总被引:1,自引:1,他引:1  
综述了邻苯二酚的合成方法及工艺路线,比较了传统合成方法与近二十年来开发的清洁合成方法之间的优缺点,重点阐述了近期新开发的两种清洁合成方法,即苯酚羟基化法和1,2—环己二醇催化脱氢法合成邻苯二酚,并对这两种合成过程所使用的催化剂及其进展做了探讨;最后对邻苯二酚的工业化合成路线及方法进行了展望。  相似文献   

3.
阐述了对我国传统尿素合成理论知识创新的必要性。运用相平衡和相图,对尿素合成过程进行了剖析,得到了现代尿素合成理论的要点,提出了基于现代尿素合成理论提高合成转化率的改造路线。  相似文献   

4.
噻吩-2,5-二羧酸合成工艺的进展   总被引:2,自引:0,他引:2  
葛广周 《化工时刊》2003,17(10):8-12
简要叙述了噻吩—2,5—二羧酸的性质和用途。详细综述了噻吩—2,5—二羧酸四大类合成路线:以己二酸为原料合成法,以糖为原料合成法,以噻吩为原料合成法,以氯乙酸为原料合成法。各大类中又根据其它原料的不同细分出几种方法,给出了具体的噻吩—2,5—二羧酸的合成步骤,并对其合成工艺的特点进行了分析。  相似文献   

5.
本文研究了TDE-85环氧树脂丙烯酸酯的合成方法,讨论了合成条件(催化剂的种类与用量,反应温度及时间,投料比,反应类型及不饱和酸种类的选择等)对合成反应及合成产物性状的影响。另外,还考察了该合成产物的UV固化特性。  相似文献   

6.
粉煤灰合成沸石的新发展及应用   总被引:2,自引:0,他引:2  
杜黎明 《粉煤灰》2006,18(6):44-46
阐述了利用粉煤灰合成沸石的基本机理,并介绍了传统水热合成法、碱熔融-水热合成法、盐-热(熔-盐)合成法等粉煤灰合成沸石的方法和其最新发展,以及利用传统的水热合成法将粉煤灰合成沸石的工业化应用情况,对粉煤灰合成沸石的应用途径和前景进行了探讨和展望。  相似文献   

7.
工业尿素合成理论(一)   总被引:1,自引:0,他引:1  
沈华民 《化肥工业》2009,36(5):9-19
以多学科综合分析法,叙述传统工业尿素合成理论和现代工业尿素合成理论的建立过程;从理论上分析了传统工业尿素合成理论的缺陷和弊病。以超临界共沸相图取代了原来的相平衡,并汲取了20世纪80年代后国际尿素技术中有关工业合成的新理念,从而诠释了工业生产上尿素合成塔中的合成反应化工过程,改进了传统尿素合成理论,建立了新型的现代工业尿素合成理论。  相似文献   

8.
环烷酸钴的制备   总被引:3,自引:0,他引:3  
王玉梅  颜英 《辽宁化工》2002,31(10):435-436,455
论述了以金属钴和环烷酸为原料合成环烷酸钴的工艺,考察了氯化钴合成工艺和处理工艺,氯化钴浓度,环烷酸酸值,碱浓度对环烷酸钴钴含量的影响,合成的氯化钴经处理达到国家标准要求,合成的氯化钴不经处理可直接用于合成环烷酸钴,产品环烷酸钴达到技术指标要求。  相似文献   

9.
中微孔复合分子筛的合成研究开发进展   总被引:1,自引:0,他引:1  
刘洪涛  鲍晓军  魏伟胜  石冈 《化工进展》2002,21(12):889-893
综述了复全分子筛合成的研究进展,介绍了原位合成法,离子交换法和纳米组装法。分析比较了各种合成方法的特点,讨论了方法的适用范围,指出复合分子筛的合成中存在的一些问题,认为合成具有大-中-小孔梯度分布的复合物和用硅铝纳米簇进行自组装合成中孔材料将是今后发展的主流。  相似文献   

10.
合成维生素E生产现状与发展趋势   总被引:4,自引:0,他引:4  
梁诚 《广西化工》2001,30(2):21-24
详细介绍了国内外合成VE的市场需求,应用及发展趋势,着重探讨了合成VE原料三甲基氢醌和异植物醇的合成工艺,并对我国合成VE工业发展提出建议。  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.
The scientific community and industrial companies have discovered significant enzyme applications to plant material. This rise imparts to changing consumers’ demands while searching for ‘clean label’ food products, boosting the immune system, uprising resistance to bacterial and fungal diseases, and climate change challenges. First, enzymes were used for enhancing production yield with mild and not hazardous applications. However, enzyme specificity, activity, plant origin and characteristics, ratio, and extraction conditions differ depending on the goal. As a result, researchers have gained interest in enzymes’ ability to cleave specific bonds of macroelements and release bioactive compounds by enhancing value and creating novel derivatives in plant extracts. The extract is enriched with reducing sugars, phenolic content, and peptides by disrupting lignocellulose and releasing compounds from the cell wall and cytosolic. Nonetheless, depolymerizing carbohydrates and using specific enzymes form and release various saccharides lengths. The latest studies show that oligosaccharides released and formed by enzymes have a high potential to be slowly digestible starches (SDS) and possibly be labeled as prebiotics. Additionally, they excel in new technological, organoleptic, and physicochemical properties. Released novel derivatives and phenolic compounds have a significant role in human and animal health and gut-microbiota interactions, affecting many metabolic pathways. The latest studies have contributed to enzyme-modified extracts and products used for functional, fermented products development and sustainable processes: in particular, nanocellulose, nanocrystals, nanoparticles green synthesis with drug delivery, wound healing, and antimicrobial properties. Even so, enzymes’ incorporation into processes has limitations and is regulated by national and international levels.  相似文献   

13.
Cycloaliphatic C21 di- and C22 tricarboxylic acids were prepared by the Diels-Alder reaction of dehydrated castor oil (DCO) fatty acids (containing 48% conjugated and 42% nonconjugated dienes) with acrylic and fumaric acids, respectively. The reaction temperature, time, catalyst concentration, and mole ratio of reactants were varied to get maximum yields of the di- and tricarboxylic acids. The unreacted DCO fatty acids were removed from the products by partition between aqueous methanol and n-hexane. The products were converted to methyl esters and characterized as the substituted cyclohexene derivatives before and after dehydrogenation with Pd/C in xylene, hydrogenation with Pd/C in decalin and oxidation with periodate-permanganate reagent and by mass and proton nuclear magnetic resonance spectrometry. The acids were converted to sodium soaps, mono- and diethanolamides and the corresponding diol and triol sulfates, and the resulting products were evaluated for their surface-active properties. The sodium soaps showed better calcium tolerance and poorer foaming power than sodium oleate. The diethanolamides were inferior to lauroyl diethanolamide in wetting and emulsifying power. The monoethanolamides were better than the respective diethanolamides and lauroyl diethanolamide in wetting property. The diol and triol sulfates were poorer in wetting and emulsifying ability and better in calcium tolerance than sodium lauryl sulfate.  相似文献   

14.
The effects of extraction temperature and preservation method on the functional properties of soy protein isolate (SPI) were determined. Four extraction temperatures (25, 40, 60, and 80 °C) were used to produce SPI and yields of solids and protein contents were determined. Three preservation methods were also tested (spray-drying, freeze-drying, and freezing–thawing) and compared to fresh (undried) samples for each extraction temperature. No differences in yields of solids and protein were observed among SPIs extracted at 25, 40, and 60 °C; however, SPI extracted at 80 °C yielded significantly less solids and protein. Extraction temperature significantly affected SPI functionality. As extraction temperature increased, solubility and emulsification capacity decreased; surface hydrophobicities, emulsification activities and stabilities, and dynamic viscosities increased; and foaming properties improved. Preservation method also significantly affected SPI functionality. Drying method did not affect the denaturation enthalpies of SPIs, but spray-dried SPIs had higher solubilities, surface hydrophobicities, and emulsification stabilities, and lower viscosities, emulsification activities and rates of foaming than freeze-dried SPI exhibited. Emulsification and foaming capacities and foaming stabilities were similar for both methods of drying. There was significant interaction between extraction temperature and preservation method for all functional properties except emulsification capacity.  相似文献   

15.
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   

16.
《Drying Technology》2013,31(8):1541-1557
ABSTRACT

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   

17.
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   

18.
抗菌剂在涂料、膜、生物智能材料等材料表面的防污领域有着极其重要的应用价值。随着环保意识的增强,长效、环境友好型的抗菌剂成为当前研究的主流。其中,聚苯胺由于其良好的生物相容性和物理化学性能,是一种极具潜力的抗菌剂。聚苯胺的抗菌机理可由自身的氧化还原活性、阳离子吸附效应及电化学活性3方面分析。概括了聚苯胺及其衍生物的结构及制备方法;进一步从杀菌防污机理出发,综述了聚苯胺及其衍生复合材料在不同防污材料中应用的研究进展,包括在接触杀菌型表面、释放杀菌型表面、抗黏附型表面3种类型的材料中的应用。此外,提出了聚苯胺在防污应用中需进一步解决的问题及发展方向。  相似文献   

19.
陈钰  刘冲  邱于荟  贲梓欣  牟天成 《化工进展》2022,41(Z1):485-496
温和条件下废旧锂离子电池的绿色高效回收具有重大意义,目前利用离子液体和低共熔溶剂回废旧收锂离子电池的综述报道较少。本综述回顾近年离子液体和低共熔溶剂回收废旧锂离子电池,分析离子液体和低共熔溶剂对不同锂离子电池正极材料回收的差异性,介绍绿色溶剂结构、酸碱性、电池组成、温度、时间、质量比等因素对回收的影响,归纳绿色溶剂回收废旧锂离子电池的热力学和动力学规律及其溶解机制,并指出利用离子液体和低共熔溶剂回收废旧锂离子电池目前存在的一些问题及其提出可能的应对策略。  相似文献   

20.
The current year's growth of Douglas fir contains galactose, unusual in that this carbohydrate makes up 78.7% of the total carbohydrate fraction. An agar diet study was undertaken to determine the effects of galactose, other carbohydrates, and terpenes on western spruce budworm larval mortality, growth rate, and adult biomas production. All concentrations of the carbohydrates and terpenes tested, as well as other mineral elements not tested, were typical of the current year's foliage of Douglas fir. In experiment I, the diet containing 5.61% total carbohydrate did not significantly affect larval mortality when compared to the control diet. However, diets containing 9.45% and 15% total carbohydrate concentrations significantly increased larval mortality 64% and 96.1%, respectively, when compared to the control. Also in experiment I, terpenes alone (78.9% morality) and terpenes in combination with 9.45% and 15% total carbohydrates significantly increased larval mortality (97.2% and 100%, respectively) when compared to mortality on the control diet (44%). To determine which carbohydrate was causing the adverse effect, 6% glucose, 6% fructose, and 6% galactose were placed individually and in combination with terpenes in diets in experiment II. The 6% galactose diet significantly increased larval mortality and reduced growth rate when compared to the control, glucose, and fructose diets. Glucose resulted in 16% less larval mortality, significantly enhanced female larval growth rate and pupal weight, but did not affect male larval growth rate and pupal weight, when compared to the control. Fructose resulted in a significant decrease in larval mortality and a general trend of enhanced female and male larval growth rate and pupal weight. Larval mortality on terpenes alone was not significantly different from the control, but terpenes with 6% galactose increased larval mortality and decreased female and male growth rate and pupal weight significantly when compared to glucose-terpene and fructose-terpene diets. No significant interactions were found between carbohydrates and terpenes in either experiment.  相似文献   

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