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排序方式: 共有483条查询结果,搜索用时 15 毫秒
41.
42.
We describe a patient with pauciarticular juvenile rheumatoid arthritis with aortic insufficiency who underwent successful aortic valve replacement with a mechanical prosthetic valve. 相似文献
43.
ADSORPTION OF ORGANICS FROM A TRUE IN-SITU OIL SHALE RETORT WATER ON ACTIVATED CARBON IN PACKED BEDS
Enayat Pedram Anthony L. Hines Richard E. Poulson David O. Cooney 《Chemical Engineering Communications》1982,15(5):291-304
The adsorption of a true in-situ oil shale retort water on activated carbon at 278 and 298 K was studied in batch experiments and in packed beds with continuous liquid flow. The isotherms were nonlinear over the liquid concentration 0 to 875 mg/1. Breakthrough curves were obtained in packed bed experiments as a function of bed length, particle size, and liquid velocity. A differential approach was used to calculate the mass transfer coefficients and the rates of adsorption. Also the breakthrough curves were analyzed to establish the relative importance of the various individual mechanisms that contributed to the overall adsorption process. 相似文献
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Cooney Ned L.; Litt Mark D.; Cooney Judith L.; Pilkey David T.; Steinberg Howard R.; Oncken Cheryl A. 《Canadian Metallurgical Quarterly》2007,21(4):570
Alcohol dependent smokers (N=118) enrolled in an intensive outpatient substance abuse treatment program were randomized to a concurrent brief or intensive smoking cessation intervention. Brief treatment consisted of a 15-min counseling session with 5 min of follow-up. Intensive intervention consisted of three 1-hr counseling sessions plus 8 weeks of nicotine patch therapy. The cigarette abstinence rate, verified by breath carbon monoxide, was significantly higher for the intensive treatment group (27.5%) versus the rate for the brief treatment group (6.6%) at 1 month after the quit date but not at 6 months, when abstinence rates fell to 9.1% for the intensive treatment group and 2.1% for the brief treatment group. Smoking treatment assignment did not significantly impact alcohol outcomes. Although intensive smoking treatment was associated with higher rates of short-term tobacco abstinence, other, perhaps more intensive, smoking interventions are needed to produce lasting smoking cessation in alcohol dependent smokers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
Many scheduling problems in project management, manufacturing, and elsewhere require the generation of activity networks to
test proposed solution methods. Single-network generators have been used for the resource-constrained project scheduling problem
(RCPSP). Since the first single-network generator was proposed in 1993, several advances have been reported in the literature.
However, these generators create only one network or project at a time; they cannot generate multi-project problems to desired
specifications. This paper presents the first multi-network problem generator. It is especially useful for investigating the resource-constrained multi-project scheduling problem (RCMPSP),
where a controlled set of multi-project test problems is crucial for analyzing the performance of solution methods. In addition
to the single-project characteristics handled by existing network generators—such as activity duration, resource types and
usage, and network size, shape, and complexity—the proposed generator produces multi-project portfolios with controlled resource
distributions and amounts of resource contention. To enable the generation of projects with desired levels of network complexity,
we also develop several theoretical insights on the effects of network topology on the probability of successful network generation.
Finally, we generate 12,320 test problems for a full-factorial experiment and use analysis of means to conclude that the generator
produces “near-strongly random” problems. Fully “strongly random” problems require much greater computational expense. 相似文献
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Fernanda Peyronel Joseph Cooney Erzsebet Papp-Szabo Silvana Martini David Pink 《Journal of the American Oil Chemists' Society》2023,100(12):961-974
Three oleogelator molecules (Triacontane (TC), Stearic acid (SA), and Behenyl Lignocerate (BL)) were studied individually, in pairs, or all together to make an oleogel using triolein as the oil. WAXS, SAXS and USAXS were used to elucidate the solid structures from angstroms to a few micrometers. A two-dimensional mapping of atomic positions for each molecule was carried out to understand the crystalline multilayer structures formed. We assumed that the molecules were rigidly extended and that they underwent no significant (hindered) rotations so that the free energy is determined by the Lennard-Jones interactions of closely packed multilayers. TC molecules were predicted to form a tilt angle of , yielding a SAXS line at Å─1, in acceptable agreement with the measured . For SA crystals (predicted) yielding a SAXS line at compared to (observed). No mixed crystals were observed for any pair of molecules or when all three were used. USAXS data showed that SA forms large nanocrystals compared to TC and BL. All three combinations of molecular pairs showed basic scatterers smaller or similar to those of individual molecules. The theory presented here, together with the experimental results, showed why no mixed crystals are formed from two or all three molecules. Data from the USAXS region suggested that, when using all three molecules, a more compact fractal structure was obtained, compared with those if one or two of the molecules were used. 相似文献
50.
EricCooney 《有线电视技术》2005,12(6):112-113
如今,欧洲的有线电视运营商正在研究增加其来自每个用户的利润并保持其用户基数的新方法。面对卫星和通信公司越来越激烈的竞争,有线电视运营商越来越希望把钱投到那些可以使其宝贵网络资产产生最大回报的新业务。而视频点播就是那些最有吸引力的新业务中的一个。 相似文献