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71.
Chloride doped polyaniline conducting polymer films have been prepared in a protic acid medium (HCl) by potentiodynamic method
in an electrochemical cell and studied by cyclic voltammetry and FTIR techniques. The FTIR spectra confirmed Cl- ion doping in the polymers. The polymerization rate was found to increase with increasing concentration of aniline monomer.
But the films obtained at high monomer concentration were rough having a nonuniform flaky polyaniline distribution. Results
showed that the polymerization rate did not increase beyond a critical HCl concentration. Cyclic voltammetry suggested that,
the oxidation-reduction current increased with an increase in scan rate and that the undoped polyaniline films were not hygroscopic
whereas chloride doped polyaniline films were found to be highly hygroscopic. 相似文献
72.
新会计准则对会计准则质量的影响 总被引:4,自引:0,他引:4
年初,国家财政部发布了新的会计准则,这是中国会计准则建设史上的重大事件。新会计准则体现出会计准则质量的几个重要标准,提高了中国会计准则的质量。同时,分析新会计准则质量方面仍存在的一些不足。 相似文献
73.
LNG冷量优化集成利用技术 总被引:7,自引:1,他引:6
我国将相继在沿海地区建成多个LNG接收站,每年将进口数以千万吨计的LNG,同时携带数着巨额冷量,而这些冷量可用于发电、空气分离、制造干冰、低温冷库等众多领域。基于国外LNG冷量利用现状,指出我国即将展开和实施此项技术还存在着:过程火用损较大,缺乏系统、全面的LNG冷量利用技术的研发指导机制,以及宏观调控力度薄弱等问题,进而提出了发展LNG冷量的集成利用方案,可为此类技术的研发利用提供新思路。以福建即将进口的LNG为例,模拟了空气分离与干冰制备的集成工艺流程,结果表明:福建每年进口的260×104t LNG可以冷却290×104t空气,相当于60000 m3/h的氧气制备规模,还可以生产100×104t的干冰,其过程火用损较小;其剩余的高温位冷量可应用于低温冻结库或冰灯等项目,这对主体装置的实施效果和过程火用损的影响较小。该技术的优点在于可灵活控制冷却空气的液化率,基本不用冷却循环水,流程简单,设备投资少,能耗低等。 相似文献
74.
75.
论文提出利用用户提供的个性化信息来随机产生关联大素数,保证了素数选取的随机化、个性化,提高了RSA算法的安全性。 相似文献
76.
Xiao Ma Li Ping 《Communications Letters, IEEE》2004,8(7):464-466
In this letter, we investigate the iterative detection/decoding algorithms for two-track partial response channels. We first describe the iterative algorithm as an iterative message-passing/processing algorithm over a high-level normal graph and then propose two trellis-based detection algorithms. The natural one is based on a joint trellis, which can be implemented for low-order channels. For moderate-order channels, we propose a separated detection, which is based on two single-track trellises. Compared with the joint detection, the separated detection is simpler in most cases. Simulation results show that, for two-track EPR4 channels with minor intertrack interferences, the separated detection causes only marginal degradation in performance. 相似文献
77.
78.
A coupled finite-element model, CON2D, has been developed to simulate temperature, stress, and shape development during the
continuous casting of steel, both in and below the mold. The model simulates a transverse section of the strand in generalized
plane strain as it moves down at the casting speed. It includes the effects of heat conduction, solidification, nonuniform
superheat dissipation due to turbulent fluid flow, mutual dependence of the heat transfer and shrinkage on the size of the
interfacial gap, the taper of the mold wall, and the thermal distortion of the mold. The stress model features an elastic-viscoplastic
creep constitutive equation that accounts for the different responses of the liquid, semisolid, delta-ferrite, and austenite
phases. Functions depending on temperature and composition are employed for properties such as thermal linear expansion. A
contact algorithm is used to prevent penetration of the shell into the mold wall due to the internal liquid pressure. An efficient
two-step algorithm is used to integrate these highly nonlinear equations. The model is validated with an analytical solution
for both temperature and stress in a solidifying slab. It is applied to simulate continuous casting of a 120 mm billet and
compares favorably with plant measurements of mold wall temperature, total heat removal, and shell thickness, including thinning
of the corner. The model is ready to investigate issues in continuous casting such as mold taper optimization, minimum shell
thickness to avoid breakouts, and maximum casting speed to avoid hot-tear crack formation due to submold bulging. 相似文献
79.
Atsushi Narumi Kosei Kawasaki Harumi Kaga Toshifumi Satoh Naoya Sugimoto Toyoji Kakuchi 《Polymer Bulletin》2003,49(6):405-410
Summary
The potato phosphorylase-catalyzed polymerization of α-D-glucose-1-phosphate (G-1-P) onto poly[styrene-block-(4-vinylbenzyl maltohexaoside)] (1) was performed at the molar ratios of [G-l-P]0 and [maltohexaose]0 of 35, 80, and 250. The product was found to be soluble in dimethyl sulfoxide, which was a good solvent for amylose, and
showed the complex-formation with iodine, indicating that the product was assignable to poly[styrene-block-(styrene-graft-amylose)] (2). The quantitative analysis of the liberated phosphoric acid gave the average degree of polymerization o f the glucose unit
(n) as 27, 5 1, and 180 for 2-I, 2-II, and 2-III, respectively.
Received: 29 November 2002/Accepted: 22 December 2002
Correspondence to Toyoji Kakuchi 相似文献
80.
涤纶工业丝环吹风改造的设计计算 总被引:2,自引:1,他引:1
应用PET纤维的冷却成形理论 ,结合空气调节的相关知识 ,提出了环吹风的设计计算方法 ,对涤纶工业丝环吹风进行了设计改造 ,满足了纺丝工艺要求 相似文献