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排序方式: 共有263条查询结果,搜索用时 31 毫秒
1.
膨化硝酸铵晶体特性研究 总被引:4,自引:0,他引:4
膨化硝酸铵是一种改性硝酸铵晶体,具有显著自敏化特征,成功应用于各类膨化硝铵炸药及震源药柱中.在膨化剂(表面活性剂)的作用下改善了膨化硝酸铵的物理性能和晶体结构及其特征.本文通过硝酸铵固体表面接触角的测量,算出了膨化硝酸晶体表面能;利用差热分析(DSC)技术给出了膨化剂对硝酸铵晶变的影响;采用x射线衍射分析了膨化硝酸铵晶体的晶格特性. 相似文献
2.
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
3.
4.
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
5.
冲床的输出主要依靠设定平衡器来实现,为了克服传统冲床调试过程中主要依赖技术人员进行理论值估算或者经验进行调节平衡器的输出而存在估算误差大的弊端和局限性,设计了一种用于冲床调试的高精度压力测试系统方案;系统中自行设计了由轮辐式应变片来构成的压力传感器,该压力传感器的结构设计可有效消除环境温度等对系统的影响,采用STM32F051芯片为核心构成压力测试数据的处理模块;该压力测试系统的压力测试范围为0~2 000 kg,阈值可以灵活设定,测试系统的线性度约为1.3%,分辨率为1 kg,标称误差可达0.1%;该压力测试系统经实际测试表明:具有成本低、性能稳定,抗干扰能力强等优点,可用于各类低速冲床的压力数据采集和处理. 相似文献
6.
信号采集器是信号和和控制器之间的枢纽,采集信号的质量和采集速度与控制质量密切相关。然而,自然界中的信号各种各样,环境复杂,而且控制器对信号的要求亦各不相同,这些都使得信号采集一直以来都存在技术难点。本文基于C8051F020单片机设计了一款多路信号采集系统,与传统的数据采集器相比,C8051F020具有集成度高、逻辑实... 相似文献
7.
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
8.
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
9.
以蛋白质得率为目标,综合考虑绿色木霉(Trichodermaviride
NUA-051)与产朊假丝酵母(Candida utilis)2.281的共生特性及营养竞争,通过木霉发酵产物还原糖对菌体生长抑制的实验研究及发酵条件实验,确立了以酸解玉米秸秆为原料生产单细胞蛋白的发酵工艺酸解玉米秸秆150g/L,木霉发酵40h接种酵母2%,(NH4)2SO4
25.0g/L,KH2PO4 6g/L、MgSO4·7H2O 0.4g/L,通风量为4.5L/L·min为,搅拌转速为600r/min,pH5~6,温度35℃.木霉发酵时间40h,酵母发酵时间24h,发酵总周期64h. 相似文献
10.
Antoine Debuigne Marie HurtgenChristophe Detrembleur Christine JérômeChristopher Barner-Kowollik Thomas Junkers 《Progress in Polymer Science》2012,37(7):1004-1030
The current review focuses on the relevance and practical benefit of interpolymer radical coupling methods. The latter are developing rapidly and constitute a perfectly complementary macromolecular engineering toolbox to the controlled radical polymerization techniques (CRP). Indeed, all structures formed by CRP are likely to be prone to radical coupling reactions, which multiply the available synthetic possibilities. Basically, the coupling systems can be divided in two main categories. The first one, including the atom transfer radical coupling (ATRC), silane radical atom abstraction (SRAA) and cobalt-mediated radical coupling (CMRC), relies on the recombination of macroradicals produced from a dormant species. The second one, including atom transfer nitroxide radical coupling (ATNRC), single electron transfer nitroxide radical coupling (SETNRC), enhanced spin capturing polymerization (ESCP) and nitrone/nitroso mediated radical coupling (NMRC), makes use of a radical scavenger in order to promote the conjugation of the polymer chains. More than a compilation of macromolecular engineering achievements, the present review additionally aims to emphasize the particularities, synthetic potential and present limitations of each system. 相似文献