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961.
《Information & Management》2014,51(8):1031-1042
Customer relationship management (CRM) has become one of the most influential technologies in the world, and companies are increasingly implementing it to create value. However, despite significant investment in CRM technology infrastructure, empirical research offers inconsistent support for its positive impact on performance. This study develops and tests a research model analyzing the process through which CRM technology infrastructure translates into organizational performance, drawing on the resource-based view (RBV) and the knowledge-based view (KBV) of the firm. Based on an international sample of 125 hotels, the results suggest that organizational commitment and knowledge management fully mediate this process. 相似文献
962.
研究了在GB/T18446-2001方法基础上改变内标物(使用无毒性记录的十二烷代替毒性大的1,2,4-三氯代苯)测定样品中游离TDI的方法。该方法简捷、快速、准确度高、精确度高、更环保。本方法的适用范围同GB/T18446-2001。 相似文献
963.
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
964.
965.
本文研究了炭黑-环氧树脂复合材料的制备工艺及炭黑填充率对材料电阻率的影响。实验结果表明,加入表面活性剂,明显改善了炭黑在环氧树脂中分布的均匀性。炭黑-环氧树脂材料具有明显的渗流效应,正温度系数效应即PTC效应,非线性伏安特性和电磁波屏蔽效应。 相似文献
966.
Crosslinked copolymers of acrylamide (AA) and ethylacrylate and some ion exchangers derived from them containing either primary amine groups, obtained by the Hofmann degradation of the amide groups, or carboxylic groups, obtained by the alkaline hydrolysis of the ester groups, were studied. Divinylbenzene and N,N′‐methylenebisacrylamide were used as crosslinkers. The starting copolymers and the corresponding ion exchangers were characterized by IR spectroscopy, swelling behavior, and thermogravimetric analysis. The ion‐exchanger properties were correlated with the crosslinker nature and the chemical reactions performed on the AA copolymers. The average molecular weight between two crosslinks, determined from the swelling data in water, was compared with that calculated on the basis of the copolymerization stoichiometry only for the carboxylic cation exchangers. In this way, the preservation of the crosslink density after the hydrolysis was revealed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2701–2707, 2003 相似文献
967.
对动态泡沫床处理过磷酸钙含氟尾气的有关技术及费用作了说明 ,指出该方法费用高 ;提出一种新方法 ,该方法不加任何化学助剂 ,采用水作吸收剂 ,只需改变动态泡沫床一些设计参数和选用一种特殊的喷头 (喷头周围设计 1个圆锥形死角区 ,使含氟气体不可能进入该区 )避免了硅胶堵塞。该方法已在湖南浦市化工总厂运行 1年多未发现堵塞 ,同时该法投资少、能耗低、排放尾气达标 相似文献
968.
Richard Kotek Dong‐Wook Jung Joon Ho Kim Brent Smith Patricia Guzman Benjamin Schmidt 《应用聚合物科学杂志》2004,92(3):1724-1730
The surface alkaline hydrolysis of fibers made from poly(trimethylene terephthalate) (PTT) was studied after extruding the polymer at high spinning speeds from 2000 to 6000 m/min and heat setting in the range of temperatures from 100 to 180°C. Fiber weight loss increased with an increasing heat‐setting temperature but it was also dependent on the spinning speed. Some of the partially hydrolyzed fibers had a well‐developed, hydrophilic surface, and pore size in the range of 0.69 to 1.20 μm. The optimum reaction and morphological conditions for increasing porosity in PTT fibers depends on spinning speed and heat‐setting temperature. A temperature of 180°C is the upper limit for heat‐setting PTT filaments but seems to be the most effective for making porous fibers. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1724–1730, 2004 相似文献
969.
970.
R-卡尼丁的合成和改进 总被引:2,自引:2,他引:2
以环氧氯丙烷为原料合成了 ( R,S) -卡尼丁 ,用二苯甲酰 - L-酒石酸对其进行了拆分 ,对反应和拆分条件进行了优化 ,并用氧化还原法实现了 S-卡尼丁的消旋化 ,使其可以回收利用。 相似文献