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1.
Hydrogenolysis of a carbobenzyloxy group (CBz) was studied utilizing molecular hydrogen in the presence of carbon-supported palladium catalyst. It was demonstrated that the kinetics of the reaction are greatly influenced by the presence of the CO2 by-product. It was found out that the presence of CO2 determines whether the reaction is first or zero order since it causes deactivation of the catalyst via inhibition. The effect of potassium carbonate (K2CO3) and triethylamine (TEA) as additives was investigated. A considerable solvent effect was also observed that may be explained by the variation of dispersion of the catalyst from one solvent to another.  相似文献   
2.
A test has been developed for measuring the amount of foam generated by a detergent composition under dynamic conditions and in the presence of sebaceous soil. Good correlation with actual practice results because the conditions of the test closely parallel practical laundry conditions. Presented at the AOCS Meeting in Minneapolis, 1963.  相似文献   
3.
This research explores the extent to which users across cultures adopt the technology of online social networks (OSNs) in order to promote or support a social cause. By surveying graduate-level university students at institutions in the United States, China and India, this research builds on prior work in technology acceptance to model and explain how three elements of the task domain – the cultural aspects of the user, the social nature of the technology, and the social nature of the task – combine to influence the constructs and relationships within a modified Technology Acceptance Model (TAM) framework as well as the behavior that flows from it. This study contributes to our understanding of technology adoption by showing how OSNs are adopted by users across cultures in promoting and supporting social causes.  相似文献   
4.
The impact of calcium–magnesium–alumino-silicate (CMAS) degradation is a critical factor for development of new thermal and environmental barrier coatings. Several methods of preventing damage have been explored in the literature, with formation of an infiltration inhibiting reaction layer generally given the most attention. Gd2Zr2O7 (GZO) exemplifies this reaction with the rapid precipitation of apatite when in contact with CMAS. The present study compares the CMAS behavior of GZO to an alternative thermal barrier coating (TBC) material, GdAlO3 (GAP), which possesses high temperature phase stability through its melting point as well as a significantly higher toughness compared with GZO. The UCSB laboratory CMAS (35CaO–10MgO–7Al2O3–48SiO2) was utilized to explore equilibrium behavior with 50:50 mol% TBC:CMAS ratios at 1200, 1300, and 1400°C for various times. In addition, 8 and 35 mg/cm2 CMAS surface exposures were performed at 1425°C on dense pellets of each material to evaluate the infiltration and reaction in a more dynamic test. In the equilibrium tests, it was found that GAP appears to dissolve slower than GZO while producing an equivalent or higher amount of pore blocking apatite. In addition, GAP induces the intrinsic crystallization of the CMAS into a gehlenite phase, due in part to the participation of the Al2O3 from GAP. In surface exposures, GAP experienced a substantially thinner reaction zone compared with GZO after 10 h (87 ± 10 vs. 138 ± 4 μm) and a lack of strong sensitivity to CMAS loading when tested at 35 mg/cm2 after 10 h (85 ± 13 versus 246 ± 10 μm). The smaller reaction zone, loading agnostic behavior, and intrinsic crystallization of the glass suggest this material warrants further evaluation as a potential CMAS barrier and inclusion into composite TBCs.  相似文献   
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6.
Correlations between psychotherapy homework (HW) and recovery from depression (DEP) could be explained by 4 models: (a) HW causes reductions in DEP; (b) reductions in DEP lead to HW compliance; (c) HW and DEP have circular causal effects on each other; and (d) HW and DEP are simultaneously influenced by a 3rd variable, such as motivation. In the D. D. Burns and D. Spangler (2000) (see record 2000-13544-005) study of HW and changes in DEP during the first 12 weeks of therapy using structural equation modeling (SEM), only the first model was consistent with the data. Still, one cannot conclude that a model is "true" or definitely confirm a causal effect, even with experimental designs. The authors recommend SEM for naturalistic and experimental designs. Quality of HW should be included in future research, as N. Kazantzis, K. R. Ronan, and F. Deane (2001) (see record 2001-05666-023) suggest. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
Discusses properties and pharmacological effects of medications for pain, including peripherally acting analgesics, centrally acting narcotics, and adjuvant analgesics including antidepressants. The role of the endogenous opioid system in pain and depression is discussed. Clinical management issues in both inpatient and outpatient settings are explored, with emphasis on the need to address the psychosocial context in which medications are prescribed. (52 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
The N-methyl-{d}-aspartate (NMDA) receptor may play a critical role in learning and memory. In the present study, a significant correlation was found between the number of NMDA-displaceable,Na+-independent {l}-[–3H]glutamate binding sites in the hippocampus and neocortex of young rats and the mean number of errors during retention, but not acquisition, in a 14-unit T-maze. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
The aim of this work is to identify major food sources and dietary constituents of Senegalese adults. We conducted a cross-sectional study, using a single 24-hour dietary recall interview. Foods were classified into food groups based on similarities in nutrient content or use. Food groups included foods consumed individually, or as part of food mixtures such as stews, soups, or sandwiches. Median consumption (amount/day) of each food was determined and examined by relevant subgroups. Participants were 50 healthy Senegalese men, aged 20-62 years recruited at the Hôpital Général de Grand Yoff in Dakar, Senegal and from Sendou village, a rural area outside Dakar. A total of 90 foods and beverages were identified and classified into 11 groups. Sixty-five percent of foods identified could be classified as meats, grains, or fruits/vegetables. Fruits and vegetables comprised 42% (38/90) of all foods; meats 12% (11/90); and grains 11% (10/90). Sauces (6%, 5/90), sweets (4%, 4/90), and desserts (4%, 4/90) were also reported. The most common fruits/vegetables reported were potato, carrot, mango, and lettuce; commonly reported grains were bread and rice; and commonly reported meats were fish, beef, and ox. There were no differences in reported daily intake of each food by age, ethnicity, education, or residence. Most foods reported were traditional to the Senegalese diet, despite the increasing availability of Western foods in Senegal.  相似文献   
10.
Exploratory Analytics is the process of analyzing data for the purpose of forming hypotheses. Patent data sets, because they are relatively large and diverse and because they consist of a mixture of structured and unstructured information present a formidable challenge and a great opportunity in applying exploratory analytics techniques. In this paper we describe methods we have implemented for effective exploratory analytics on patent data sets using an interactive approach and a web based software tool called SIMPLE. We use real-world case studies to demonstrate the effectiveness of our exploratory analytics approach in the discovery of useful information from the patent corpus.  相似文献   
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