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101.
周效全 《天然气工业》2004,24(9):97-100
油田化学专用技术的核心是各种功能的油田化学药剂和由此形成的多系列的油田化学工作液体系。而油田化学药剂是油气田勘探、开发、生产和输运等过程中必须的化学物质,它的功能和质量直接影响着钻井质量、采收率和油气生产综合开发成本。油田化学药剂的创新离不开油田化学作用机理研究的创新、突破与发展,文章以滤失控制变粘酸酸液体系配方技术、高粘型W/O自动破乳乳化酸酸液体系配方技术、低粘型W/O自动破乳乳化酸酸液体系配方技术、自动防乳破乳胶束酸酸液体系配方技术、无聚合物自转向酸液体系配方技术、EOR采油用疏水缔合聚合物体系配方技术、缓释放技术在油田化学工作液体系配方技术和两性离子聚合物钻井液体系配方技术等方面的油田化学新作用机理研究的创新突破与发现为例,论述了油田化学新作用机理研究与发现对油田化学专用技术创新应用的贡献。  相似文献   
102.
随着科技的发达,人们的生活真是越来越舒适了。我们轻松地利用遥控器开启车库大门、电视机、录像机、DVD放映机,我们也能以无线电话、呼叫器、以PDA随时随地进行通讯联络。我们甚至能运用无线技术来监看婴儿房的动静。无线技术已成为生活中不可或缺的一部份,并且被视为理所当然的必须品。还记得必须从沙发上起身去按电视机按钮的日子吗? 现在即使是更换遥控器电池,就会被认为是不方便的事。近年来,我们对无线技术的接纳度已日趋成熟。我们不仅希望使用各种无线装置,更希望这些装置传输速度更快、价格更低廉、并能提供更高的频宽。我们也希望无线装置、家庭剧院系统以及数据网络能具备安全、稳定、以及可靠等特性;并且在彼此紧邻相近时,不会产生相互干扰的现象。而这个趋势将促使现今领先市场的红外线(IR)、27MHz、以及900MHz在内的装置难以继续发展;因此2.4GHz无线技术将取而代之成为市场的主流。  相似文献   
103.
Calibration methods that apply relative techniques to map robot inaccuracy increase robot flexibility by allowing for greater use and application of off-line path planning techniques. To successfully implement the off-line techniques described in this article, methods have been integrated for off-line tool control frame (TCF) calibration, data base integration, and on-line robot inaccuracy correction. The TCF calibration methods presented in this article successfully determine the TCF origin of the end-effectors and sensors attached to the robot distal link to within the robot repeatability. When the methods were applied to a SEIKO DTRAN RT-3000 robot, the TCP origins were statically predicted correct to within 0.025mm (0.001 in.). On-line methods determine robot inaccuracy by mapping robot configurations relative to operational parts or to spatial templates, in contrast to the contemporary global mapping approaches. For the Seiko robot the resulting inaccuracy distributions permit simple error correction equations to be applied, improving robot positioning accuracy to less than ±0.1 mm in locally large regions and to within the repeatability of the robot ±0.025 mm) in smaller regions. This represents an order-of-magnitude decrease in robot inaccuracy.  相似文献   
104.
We report the sudden onset of bilateral hearing loss in a patient with Crohn's disease while the intestinal disease was quiescent. Antibodies directed against collagen type II were detected in the serum. Dramatic improvement of his hearing was observed under corticosteroid therapy. Diagnosis of autoimmune sensorineural hearing loss was established. This condition could be considered as an extraintestinal manifestation of Crohn's disease. Early diagnosis is mandated, as prompt and intensive treatment with corticosteroids and/or immunosuppressive drugs is effective and could prevent irreversible hearing loss.  相似文献   
105.
过去两年来,消费品市场的供应链出现一系列深刻的结构调整.无线芯片供应商面临一个关键问题:哪些公司将成为蠢笨的巨人,哪些公司能够灵巧地适应新环境并生存下来?  相似文献   
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108.
Examined age and sex trends in emotional intensity in 432 Ss from adopting and nonadopting biological families. It was hypothesized that younger adults and females would report greater average levels of both positive and negative affect over time, as has been demonstrated in past research. 242 Ss (parents and offspring) completed a battery of mood scales. 190 Ss completed an affect intensity measure and a general behavior inventory. In support of the hypothesis, women scored higher on measures reflecting emotional intensity and manifestation of cyclothymic symptoms, and the scores on these measures decreased through the adult life span for both males and females. Potential reasons for the differences in emotional intensity are discussed. These include biological causes, cultural expectations, and current life experiences. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
The covariation of resources such as money, family support, social skills, and intelligence with subjective well-being (SWB) was assessed in 195 college students. Informant ratings provided an index of resources. Self-reports, daily experience sampling, and informant reports were used to measure SWB. The authors concluded that resources taken together are moderately strong predictors of SWB. This conclusion, however, was qualified by the fact that life satisfaction was more closely related to resources than was affective well-being and that social and personal resources were in general more strongly related to SWB than were material resources. The findings also supported the hypothesis that resources correlate more strongly with SWB when they are relevant to an individual's idiographic personal strivings. A tendency was found for people to choose personal strivings for which they have relevant resources, and the degree of congruence of individuals' goals with resources was predictive of SWB. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
Assessed whether lack of self-awareness and conscious planning, group unity, and disinhibited behavior occurred together in deindividuating settings as predicted by E. Diener's (1979) theory of deindividuation. The characteristics and effects of group-induced deindividuation with non-socially-induced non-self-awareness was also compared. The 3 conditions were deindividuated, non-self-aware, and self-aware. After the manipulations, 126 undergraduates chose inhibited vs disinhibited tasks in a supposed "creativity" session, followed by a variety of deindividuation measures. Results reveal that the deindividuation group surpassed the other 2 on the deindividuation factor and on most of the individual measures. For some of the variables, the deindividuation and non-self-aware groups differed significantly, suggesting that deindividuation may not be identical in every respect to lack of self-awareness induced in a non-social way. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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