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排序方式: 共有1030条查询结果,搜索用时 15 毫秒
81.
Anita S.Becker 《电子产品世界》2001,(14):42-44,52
因特网家电(IA)是任何具有因特网访问能力的电器的总称.确实,一类全新的设备,便携式无线Web图形输入板,正从WeB设备中脱颖而出,成为潜在的“杀手锏“.新型设备(包括智能电话、PDA),正源源不断地进入市场.由于这些重量轻、笔记本大小的因特网访问设备方便、实用,所以很多电脑生产商和供应商也无法抗拒这个巨大市场的魅力.
…… 相似文献
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Sujith Vengayil M. Vanathi Anita Panda Sudharshan Khokhar 《Contact lens & anterior eye》2008,31(3):161-163
PURPOSE: To report a case of retained Descemet's membrane after penetrating keratoplasty for congenital hereditary endothelial dystrophy (CHED) documented by anterior segment optical coherence tomography and review of literature. METHODS: Case report and review of literature. RESULTS: A 14-year-old boy underwent penetrating keratoplasty for CHED. A retained host Descemet's membrane was detected with a supernumerary anterior chamber on the first postoperative day. The retained Descemet's membrane was documented using slit lamp adapted anterior segment optical coherence tomography (SLOCT). Surgical intervention for the Descemet's membrane removal was done in the third postoperative week. The complete removal of the membrane was confirmed on SLOCT. CONCLUSION: Inadvertent retention of the host Descemet's membrane is a rare but possible complication in penetrating keratoplasty for CHED. Proper anticipation, early detection and removal will help in preventing any undue risk of graft failure. 相似文献
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Presents 5 paradoxes of masochism, which delineate intrapsychic and interpersonal patterns in which pain and "unpleasure" seem to become aims. Elements of the apparent contradictions inherent in masochistic disorders and some of their transference and countertransference implications are discussed. The 5 paradoxes highlight (1) intrapsychic conflict around issues of drive and defense, (2) conflict between autonomy and gratification through depending on others, (3) pain inherent in the quest for perfection, (4) pain associated with attachment to the object, and (5) pleasure evokes physical pain and injury, a screen for early dire physical trauma. Case material illustrates each paradox. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
Stephens BS Kapernick A Eaglesham G Mueller J 《Environmental science & technology》2005,39(22):8891-8897
Water-sampler equilibrium partitioning coefficients and aqueous boundary layer mass transfer coefficients for atrazine, diuron, hexazionone and fluometuron onto C18 and SDB-RPS Empore disk-based aquatic passive samplers have been determined experimentally under a laminar flow regime (Re = 5400). The method involved accelerating the time to equilibrium of the samplers by exposing them to three water concentrations, decreasing stepwise to 50% and then 25% of the original concentration. Assuming first-order Fickian kinetics across a rate-limiting aqueous boundary layer, both parameters are determined computationally by unconstrained nonlinear optimization. In addition, a method of estimation of mass transfer coefficients--therefore sampling rates--using the dimension-less Sherwood correlation developed for laminar flow over a flat plate is applied. For each of the herbicides, this correlation is validated to within 40% of the experimental data.The study demonstrates that for trace concentrations (sub 0.1 microg/L) and these flow conditions, a naked Empore disk performs well as an integrative sampler over short deployments (up to 7 days) for the range of polar herbicides investigated. The SDB-RPS disk allows a longer integrative period than the C18 disk due to its higher sorbent mass and/or its more polar sorbent chemistry. This work also suggests that for certain passive sampler designs, empirical estimation of sampling rates may be possible using correlations that have been available in the chemical engineering literature for some time. 相似文献
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Anita R Jindal Alistair S Grandison Geoffrey Campbell-Platt 《Journal of the science of food and agriculture》1993,61(4):449-456
Chhana whey contains less protein than Cheddar cheese whey, acid casein and cottage cheese whey, and the protein composition is quite different. Electrophoretic methods demonstrated that most of the proteins in chhana whey were denatured, and there was considerable variation in the protein composition between samples of chhana whey and paneer whey obtained from different sources. The effect of storage temperature and time (up to 10 h at 40°C, 50°C, 60°C, 70°C and 80°C) on the quality of chhana whey was investigated. There were no significant changes in the pH and titratable acidity in any of these cases. Electrophoretic separation showed no qualitative changes in the protein composition pattern of chhana whey after up to 10 h of storage at 70°C. 相似文献
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Microsystem Technologies - The technique of hiding knowledge in certain details is steganography. One of the main trends of computer infrastructure and connectivity following the advent of the... 相似文献
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Wireless Personal Communications - Wireless sensor network is gaining popularity due to its large-scale deployment in Internet of Things. The constraints of resources influence the protocol design... 相似文献