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1.
Polynitroalcohols (PNA) were obtained by AN‐reaction of nitro oligomers from ground waste rubbers (NO‐GWR) with C1‐C2‐aldehydes in presence of organic bases triethanolamine, triethylamine and cyclopropylamine. The AN‐reaction was studied at temperatures from 30 to 50°C, time 4 h, and NO‐GWR : aldehyde = 1 : 0.5/2.0 mass ratios in the solution. PNA were characterized by elemental analyses, such as 1H NMR spectra, IR spectroscopy—baseline method with internal standard and thermal analyses. The quantitative functional composition of PNA (%NO2, %C?O, and %OH groups) was proved to be similar to the composition of PNA obtained from model butadiene–styrene nitro oligomer (BSNO). It was concluded that NO‐GWR could replace NO based on elastomers in nitro aldol reaction with formaldehyde and acetaldehyde. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3241–3250, 2006  相似文献   
2.
抚顺引进的50000t/y丙烯腈装置要改造到70000t/y的生产能力,其中更换国产催化剂MB-86是较为关键的一步,文章对此进行了总结与分析。  相似文献   
3.
USB接口通讯系统应用开发   总被引:5,自引:1,他引:5  
文中介绍了Cypress公司EZ—USB芯片AN2131QC的结构、特点及使用方法,基于AN2131QC芯片设计了USB接口通讯系统。详细分析了系统中各硬件电路模块的设计思路,讨论了开发EZ—USB firmware Frame Works、主要功能模块firmware的流程,并给出了PC机中USB通讯驱动程序方案。经实际测试,证实USB接口通讯系统设计是成功的。  相似文献   
4.
数据库图形化技术是综合数据库技术和图形技术而形成的一种新兴技术,在当前的互联网中有很大的应用前景。本文介绍了数据库图形化技术,包括ActiveX控件和开放式数据库互连(ODBC)在接入网(AN)管理系统中的应用。  相似文献   
5.
介绍了低爆速膨化硝铵炸药的制备技术特点 ,通过配方设计及试验研究 ,得到低爆速膨化硝铵炸药的最佳配方 ,其性能为爆速约 2 1 0 0 m/ s,传爆距离在 50 m以上 (装药直径 32 mm)  相似文献   
6.
Total anthocyanins (TAC) and individual anthocyanidins (AN) after hydrolysis were measured in 15 red and purple-fleshed potato cultivars produced in five different locations in the Czech Republic and a new cultivar Blaue St. Galler from Switzerland. It was found that TAC, expressed as cyanidin content, varied between 0.7 mg 100 g−1 FW (cv. Blue Congo) and 74.3 mg 100 g−1 FW (cv. Blaue Ludiano). Major differences in cultivars were found for AN relative abundance. For cv. Highland Burgundy Red a high proportion of pelargonidin (98.7%) was characteristic, whereas cv. British Columbia Blue contained almost exclusively cyanidin. Cultivars Violette and Vitelotte showed a relatively high content of malvidin. Cultivar Shetland Black differed from others with its higher content of peonidin (on average 36.7%). High petunidin abundance in the cultivars Valfi, Blue Congo, Salad Blue, Blaue St. Galler, Blaue Hindel Bank, Blaue Ludiano, Blaue Schweden, Farbe Kartoffel and Salad Red was found. TAC and AN contents highly corresponded with antioxidant activity (AA) determined with the ABTS, FRAP and DPPH assays in vitro. High AA was shown by the cultivars Vitelotte, Violette, Blaue Ludiano, Hafija, and Highland Burgundy Red. Increased height above sea level, higher annual sum of precipitation, and lower annual average temperatures caused higher AA and TAC. A high degree of hydroxylation and/or methoxylation of individual anthocyanidins could contribute in conjunction with other phenolics to high AA (peonidin, delphinidin and malvidin in the cultivars Blue Congo, Highland Burgundy Red and Shetland Black). Consequently, new red and purple-fleshed cultivars with high TAC and highly methoxylated and/or hydroxylated AN could be a promising source of favourable antioxidants in human nutrition.  相似文献   
7.
Ionic liquids as electrolytes   总被引:5,自引:0,他引:5  
Salts having a low melting point are liquid at room temperature, or even below, and form a new class of liquids usually called room temperature ionic liquids (RTIL). Information about RTILs can be found in the literature with such key words as: room temperature molten salt, low-temperature molten salt, ambient-temperature molten salt, liquid organic salt or simply ionic liquid. Their physicochemical properties are the same as high temperature ionic liquids, but the practical aspects of their maintenance or handling are different enough to merit a distinction. The class of ionic liquids, based on tetraalkylammonium cation and chloroaluminate anion, has been extensively studied since late 1970s of the XX century, following the works of Osteryoung. Systematic research on the application of chloroaluminate ionic liquids as solvents was performed in 1980s. However, ionic liquids based on aluminium halides are moisture sensitive. During the last decade an increasing number of new ionic liquids have been prepared and used as solvents. The general aim of this paper was to review the physical and chemical properties of RTILs from the point of view of their possible application as electrolytes in electrochemical processes and devices. The following points are discussed: melting and freezing, conductivity, viscosity, temperature dependence of conductivity, transport and transference numbers, electrochemical stability, possible application in aluminium electroplating, lithium batteries and in electrochemical capacitors.  相似文献   
8.
徐海东 《辽宁化工》2003,32(8):362-363,368
在讨论丙烯腈生产装置的工艺原理的基础上,采用基于相关系数辨识法的AtLoop PID自动整定软件,优化整定了丙烯腈装置部分常规PID控制器参数,取得了较好的控制效果,为反应系统的在线优化提供了有利的条件,同时对产品质量的提高大有好处。  相似文献   
9.
以荷斯坦高产和中产奶牛为例,研究其粪便含水量、粪尿中总氮(TN)、氨态氮(AN)浓度和NH3、H2S的散发量。选取高产和中产奶牛牛舍各一栋,测定粪便含水量、粪尿中总氮(TN)氨态氮(TN)质量分数以及粪中NH3和H2S气体的散发量。结果表明,粗蛋白的摄入与需求比增加,奶牛粪尿中氮和硫的质量分数也会增加。超过动物蛋白质需要量的几乎所有的氮都是通过尿液排出体外,尿氮增加的幅度大于粪氮增加的幅度。因此,减少粪氮不是降低氮污染的有效途径。  相似文献   
10.
通过原位聚合方法制备了聚(丙烯腈-醋酸乙烯酯)/蒙脱土(P(AN/VA c)/C lay)纳米复合材料。通过TEM、X-R ay、IR、NM R、DSC、TG对其形貌、粒径、组成、结晶结构和热性能等进行了表征,结果表明,P(AN/VA c)/C lay纳米复合材料的粒径尺寸为50 nm~80 nm,并呈多片层结构,clay片层均匀分布于P(AN/VA c)基体中,其耐热性均优于P(AN/VA c)。  相似文献   
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