首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
姜守霞  张强 《辽宁化工》1997,26(3):141-143
苯乙烯是重要的石油化工原料。本文介绍了国内外苯乙烯生产的发展概况,合成乙苯,苯乙烯所用的催化剂种类,并就苯乙烯生产及催化剂的发展趋势提出了自己的观点。  相似文献   

2.
生物质气化及生物质与煤共气化技术的研发与应用   总被引:1,自引:0,他引:1  
总结了生物质原料的特点及生物质单独气化的缺点;介绍了国内外生物质气化技术及生物质与煤共气化技术的研发与应用现状;分析了在此领域国内外的发展趋势与前景;概括了开展生物质与煤共气化技术研发的意义。  相似文献   

3.
医药和农药纳米剂型研究和应用   总被引:5,自引:0,他引:5  
系统介绍了医药和农药纳米剂型研究进展和应用前景。医药微乳剂和纳米悬浮剂可显著改善药物的悬浮性和分散性,提高生物利用度。载药纳米微粒具有缓释功能,延长药物在体内的半衰期,并可实现药物的靶向定位给药。农药微乳剂具有增溶和渗透作用,提高农药的传递效率和使用安全性。农药纳米悬浮剂和载药纳米粒均可显著提高药效。纳米技术为医药和农药剂型的研究提供了新机遇,具有广阔的应用前景。  相似文献   

4.
责任是人应主动承担的角色义务和对其因过失所造成后果应承担的责罚.有两层涵义:一是义务;二是后果.责任心是个体自觉做好分内事务和履行道德义务的心理倾向,是个性心理品质成分中自我特征维度上的重要内容.责任心具有两个方面的涵义:一是角色分内职责;二是角色道德义务.责任心是一种通过责任认知、责任个性和责任适应的动态形式表现出来的静态品质,责任心是责任心过程结构与责任心关系结构相互制约、相互影响的统一体.  相似文献   

5.
《国际聚合物材料杂志》2012,61(1-4):113-122
Abstract

Kinetics and mechanisms of oxidation of 6 acetals by molecular oxygen and ozone in liquid phase have been studied. Reaction with molecular oxygen (70°C, 15–16 hr) leads to the formation monoethers of the corresponding glycols with 68–90% selectivity. Salts of metals and complexes with crown-ethers have increased the reaction rate significally. Ozone have reacted with acetals with formation similar products. The mechanisms of intermediate stages have been proposed.  相似文献   

6.
泡沫起泡性、稳定性及评价方法   总被引:6,自引:0,他引:6  
本文论述了泡沫的两个基本性质:起泡性和稳定性。对起泡性和提高泡沫稳定性的方法作了评价。  相似文献   

7.
The variation of the Au 4f binding energy of Au clusters with the cluster size has been established by measuring the binding energies of clusters whose size distributions were independently determined by HREM and STM. The binding energy increases significantly when the cluster size is less than 2 nm. Au-Cu bimetallic clusters of the composition Cu3Au have been deposited for the first time on carbon substrates. The shifts in the core level binding energies of the bimetallic clusters show the effect of alloying in the case of large clusters, but show effects of both alloying and cluster size in the case of the small clusters. The interaction of CO with Cu3Au clusters is stronger than with a bulk Cu metal. The interaction of CO with small Cu clusters also seems to be stronger than with bulk Cu or with large Cu clusters.  相似文献   

8.
塑料挤出机螺杆,机筒耐磨损,耐腐蚀的强化与应用   总被引:4,自引:0,他引:4  
李金钊 《中国塑料》1999,13(9):83-88
对塑料挤出机,注塑机螺杆,机筒的磨损,腐蚀原因及提高螺杆,机筒耐磨损,耐腐蚀的方法、制造与应用作了较详尽的介绍。  相似文献   

9.
介绍了内蒙古亿利化学工业有限公司在满足生产的前提下,对现有的循环水泵实施的节能技改及效果。  相似文献   

10.
This work deals with modelling of emulsion polymerization processes using batch and semi-batch reactors. Specific attention is paid to copolymerization of the system styrene/butyl acrylate.The main key parameters of the model are identified on the basis of batch experimental data in order to describe the complete sketch of emulsion polymerization. The model is then used to simulate, under several operating conditions, the polymerization rate, the global monomers conversion, the number and weight average molecular weights as well as the particle size distribution and the glass transition temperature. Then, the model is generalized to the use of semi-batch processes and validated for this application.  相似文献   

11.
对用甘油锌作光稳定剂的光稳定作用进行了测试,并与光稳定剂NBC,BZ进行了比较。研究了甘油锌,NBC和BZ与双酚A的复配效果。研究结果表明,甘油锌是一种性能优良的光稳定剂。  相似文献   

12.
This study aimed to investigate the structural features, antioxidant activity, tyrosinase inhibitory effect, and mechanism of proanthocyanidins from leaf and fruit of Leucaena leucocephala. MALDI-TOF-MS, thiolysis coupled with HPLC-ESI-MS, and 13C-NMR confirmed that these proanthocyanidins were complex mixtures of propelargonidins, procyanidins, and prodelphinidins. (Epi)catechin, (epi)gallocatechin, (epi)catechin gallate, and (epi)gallocatechin gallate were the main constitutive units. The findings obtained from enzyme analysis revealed that the proanthocyanidins had inhibitory effects on both monophenolase and diphenolase of tyrosinase. The IC50 values of leaf and fruit proanthocyanidins were 73.5?±?2.7 and 52.3?±?3.5 µg/mL for monophenolase activity, and 27.2?±?1.4 and 16.1?±?1.1 µg/mL for diphenolase activity, respectively. The inhibition of diphenolase by proanthocyanidins were proved to be reversible and mixed type. In addition, it was also found from various antioxidant methods that the proanthocyanidins in leaf and fruit possessed potent DPPH radical scavenging activity with IC50 values of 103.4?±?0.8 and 87.8?±?1.1 µg/mL, ABTS radical scavenging activity with IC50 values of 72.9?±?0.4 and 65.7?±?0.9 µg/mL, and ferric reducing antioxidant power with FRAP values of 3.74?±?0.03 and 4.02?±?0.15?mmol AAE/g, respectively. The results obtained suggested that the proanthocyanidins from leaf and fruit of L. leucocephala might have the potential to be exploited as natural tyrosinase inhibitors and antioxidants.  相似文献   

13.
针对高校环境工程和给水排水工程实验和校内实习手段单一的现状,学校建立了这两个专业的工程性实验和校内实习基地.该基地包含两套工艺系统,可以分解成10余套流程,不仅可以开设十几个单元操作实验和多个工程性工艺实验,还作为学生可以动手操作的实习基地.经过实践证明,这种实验和实习模式可以提高学生的动手能力和创新能力.  相似文献   

14.
羟基和氨基苯类化合物的生物氧化与代谢   总被引:1,自引:0,他引:1  
姚日生  孙敏  王磊  邓胜松 《化工学报》2006,57(2):367-370
引言 芳香类污染物是自然界分布广泛的一类化合物,主要来源于石油工业、造纸业、塑料加工、纤维制造以及农药生产等[1].其中大多数酚(羟基苯)和芳香胺(氨基苯)具有很强的毒性和致癌性,因此被很多国家列为首要污染物[2-3].由于物理处理法和化学处理法成本高且可能引入其他有害物质[4],人们日益关注成本低廉而处理彻底的生物法[3].  相似文献   

15.
介绍了近期国内外氟化工产品的生产、应用和市场动态 ,尤其对国内目前氟塑料工业的发展前景进行了较详细的阐述。同时提出了一些具有开发前景的氟塑料产品  相似文献   

16.
肥皂和表面活性剂的配方与性质   总被引:1,自引:0,他引:1  
将表面活性剂添加到以肥皂为基剂的配方中,可有效降低体系的pH值,如选择合适的中和试剂和表面活性剂还可使溶液呈透明状.同时,专业小组的研究表明:某些表面活性剂的加入可有效提高肥皂配方的许多其他表观特性.  相似文献   

17.
黄宗实 《国外塑料》2002,20(3):33-35,45
介绍混料和母料的生产和应用情况,生产商,经锁商与消费用户之间的紧密合作,协调关系以及发展趋势。  相似文献   

18.
李仕超  孔艳 《四川化工》2009,12(3):20-24
介绍了国内外合成丁辛醇的工艺技术进展情况,包括戴维合成法、三菱化成合成法、巴斯夫合成法等。在比较不同生产工艺路线的同时,从现有技术成熟角度和应用情况对比,提出了低压羰基法合成丁辛醇的选择原则。同时阐述了未来丁辛醇合成技术的发展趋势。  相似文献   

19.
冯溶  张政  王欣 《农药》2003,42(11):29-30
利用气相色谱-质谱联用仪对胺丙畏样品进行分离,鉴定出异构体的存在,通过NMR波谱仪进一步表征了顺式及反式异构体。  相似文献   

20.
介绍了国内外关于塑料制品安全性和环保性的法律、法规等要求,对国内塑料抗氧剂生产、应用中存在的相关问题进行了分析和探讨。指出国内塑料制品的安全性和环保性不仅仅与生产技术和市场有关,还与公众的安全和环保意识有关。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号