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991.
Blended polymer electrolytes based on poly(ethylene oxide) (PEO) and boroxine ring polymer (BP) solvated with lithium triflate were formulated and evaluated. Compared to PEO–salt polymer electrolyte, ionic conductivities of blended polymer electrolytes were two orders of magnitude higher in a low‐temperature range; as well, lithium transference numbers were increased to ~ 0.4. These were due to the increased mobility and anion trapping of boroxine rings. BP also exhibited the stabilizing effect on lithium–polymer electrolyte interface, and a reduced interfacial resistance between lithium metal and the polymer electrolyte was found with increasing of BP content. Polymer electrolytes based on PEO and BP are suitable for use in lithium secondary battery. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 17–21, 2002; DOI 10.1002/app.10090 相似文献
992.
Ozonolysis of cyclododecene was carried out to produce an w-formyl carboxylic acid (12-oxododecanoic acid) which is derived
from zwitterion and aldehyde moiety that are formed during the reaction. The ozonolysis was performed to examine the product
distribution under such reaction variables as temperature, kinds of solvent, and presence of catalyst. The yield of polymeric
ozonide, which is undesirable product, was measured to be dominantly 86% without pyridine catalyst, whereas, only 10.25% with
the catalyst. The optimum reaction condition was to be in MC (methylene chloride) solvent, and in the presence of equimolar
olefin and pyridine catalyst at O°C, at which the yields of polymeric ozonide, 1,12-dodecanedialdehyde, 1,12-dodecanedicarboxylic
acid, and 12-oxo-dodecanoic acid were 10.25%, 26.72%, 26.31%, and 36.72%, respectively. 相似文献
993.
994.
Traditional methods based on the product of exponentials (POE) formula are parametrically continuous and complete for the calibration of the kinematic parameters of serial robots. However, these methods are not minimal due to the constraints of joint twists. This paper puts forward a new POE-based model, whose parameters are totally independent and conform to the formula of minimality. This is the first model that simultaneously satisfies the requirements of parametric continuity, completeness, and minimality with uniform and generic modeling rules. The proposed approach avoids the operations of normalization and orthogonalization which are necessary redundancy elimination steps with the traditional model. Simulations on a SCARA robot and experiments on an ABB IRB 120 robot prove that the new model outperforms in convergence, accuracy, and efficiency. 相似文献
995.
煤岩配煤技术的发展与现状 总被引:3,自引:0,他引:3
煤岩学在炼焦配煤技术上的应用,使炼焦配煤手段更有效,使焦炭质量预测在生产上应用成为可能,为定性的经验配煤技术跃变到定量的科学配煤技术创造了条件。夏皮洛煤岩配煤技术是目前较好的配煤方法,其相关系数可达0.93;国内许多学者在煤岩配煤方面也做了大量研究工作,有些相关系数达0.98。目前虽然各种方法存在一定局限性,但随着计算机和图像处理技术的发展,煤岩学在指导配煤技术方面将有新的突破。 相似文献
996.
997.
A series of poly(?‐caprolactone)‐b‐poly(ethylene glycol) (PCL‐b‐PEG) block copolymers with different molecular weights were synthesized with a salicylaldimine‐aluminum complex in the presence of monomethoxy poly(ethylene glycol). The block copolymers were characterized by 1H NMR, GPC, WAXD, and DSC. The 1H NMR and GPC results verify the block structure and narrow molecular weight distribution of the block copolymers. WAXD and DSC results show that crystallization behavior of the block copolymers varies with the composition. When the PCL block is extremely short, only the PEG block is crystallizable. With further increase in the length of the PCL block, both blocks can crystallize. The PCL crystallizes prior to the PEG block and has a stronger suppression effect on crystallization of the PEG block, while the PEG block only exerts a relatively weak adverse effect on crystallization of the PCL block. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
998.
叙述了以液—液萃取、间歇精馏为手段,从四氢呋喃、甲醇、水三元混合物系中分离四氢呋喃的方法。四氢呋喃纯度超过98%,收率64.8%。 相似文献
999.
1000.
针对Hyperbola模型和Logistic模型的优缺点,提出Hyperbola-Logistic叠加模型,该叠加模型综合了两种单项预测模型的优点,以期达到高精度的预测结果。结合发电厂地基沉降现场观测数据,利用Hyperbola-Logistic叠加模型预测地基沉降,并与单项沉降预测模型的拟合结果进行比较分析。结果表明:与两种单项预测模型的预测结果相比较,叠加模型减小了系统误差,提高了整体的预测精度,拟合结果可靠,适用于发电厂地基沉降量的预测。新模型具有一定的适用性,是一种分析预测地基沉降的有效方法。 相似文献