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81.
The enhancement of the 1 day strength of cementitious systems by a combination of calcium chloride (CaCl2) and diethanol-isopropanolamine (DEIPA) was studied, particularly in blended cement systems. A combination of quantitative X-ray diffraction with Rietveld refinement (QXRD), scanning electron microscopy (SEM)/backscattered electron image analysis, thermogravimetric analysis (TGA), and isothermal calorimetry were used to investigate the mechanism of strength enhancement by the additives. The additives were found to increase the early age mortar strength by enhancing the cement hydration, with the DEIPA enhancing primarily the aluminate hydration. DEIPA also affected the morphology of portlandite which was formed as thin plates. In parallel, the calcium-to-silica ratio of the C-S-H was found to increase with the use of DEIPA, possibly because of the inclusion of microcrystalline portlandite. After 48 h DEIPA was found to directly enhance the rate of reaction of granulated blast-furnace slag and fly ash. 相似文献
82.
Juliana Q. Mollica Denise C. Cara Mirna D’Auriol Verena B. Oliveira Isabela C. Cesar Maria G.L. Brandão 《Journal of Functional Foods》2013,5(4):1975-1984
Tropical ecosystems are particularly rich in edible plant species with different bioactive substances. Among the plants with promising benefits for health are species from the genus Dioscorea (Dioscoreaceae), especially those named yam. Recent studies have shown the beneficial effects of different species of Dioscorea, and its main constituent, diosgenine, in the treatment of food allergy. In this study we evaluated the potential of D. trifida, the only yam native from South America, in the treatment of ovalbumin (OVA) induced food allergy in Balb/c mice. HPLC/DAD analysis showed the presence of three very distinctive groups of natural products in extracts and fractions: (I) very polar substances, including allantoin, (II) phenolic substances as flavonoids and phenolic acids and (III) diosgenin and derivatives. Sensitive mice received casein feed with supplementation of crude extract (CE) and fractions. The supplementation with all products from D. trifida reduced IGE, intestinal oedema and mucus production, parameters observed in OVA allergic mice. The results showed the potential of this food to prevent or treat this disease and the necessity to be better explored. 相似文献
83.
V.M.F. Alexandre A.M. Valente Magali C. Cammarota Denise M.G. Freire 《Renewable Energy》2011,36(12):3439-3444
The effect of a lipase-rich enzyme preparation produced by the fungus Penicillium simplicissimum on solid-state fermentation was evaluated in a 4.9 L up-flow anaerobic sludge blanket bioreactor (UASB) treating fish-processing plant wastewater containing 1500 mg oil and grease (O&G)/L. The oil and grease hydrolysis step was carried out with 0.5% or 0.2% (w/v) of the solid enzyme preparation (SEP) at 30 °C for 8 h. The bioreactor operated at 30 °C with a hydraulic retention time of 10 h for a period of over 100 days, showed high total COD removal efficiencies (85.3% for 0.5% SEP and 90.9% for 0.2% SEP), when fed with pre-hydrolyzed wastewater, compared to a Control bioreactor fed with raw wastewater (79.9%). The Control bioreactor also showed high oil and grease accumulation in the biomass throughout the operational period (the O&G content reached 1.7 times that found in the inoculum of the UASB bioreactor), intensive scum formation, and several episodes of cessation of treatment to clean the three-phase separator. Thus it can be concluded that the enzyme pre-hydrolysis step together with anaerobic treatment of the fish-processing plant wastewater improved the quality of the treated effluent and reduced operational problems. 相似文献
84.
Comments on the article by N. F. Kozlowski et al (see record 1998-10341-011) about HIV infected clients and whether or not there ought to be notification. Kozlowski et al cite the California case of Tarasoff v. Regents of University of California (1976) 9 times, however, they never officially cite it, nor do they put it in their reference section. Without going into a refresher course about the meaning of Tarasoff, when employing this case law in a study it is important to (1) carefully read the case, (2) become familiar with the case law in your state or states, (3) shepardize all relevant cases to make sure that they are still good law (there has been a lot of movement with Tarasoff over the years), and (4) have at least a consultation with an attorney who is familiar with this area of law. Legal accuracy is extremely important and without it, our studies cannot withstand interdisciplinary scrutiny. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
Head Denise; Raz Naftali; Gunning-Dixon Faith; Williamson Adrienne; Acker James D. 《Canadian Metallurgical Quarterly》2002,17(1):72
This study examined the impact of age-related differences in regional cerebral volumes and cognitive resources on acquisition of a cognitive skill. Volumes of brain regions were measured on magnetic resonance images of healthy adults (aged 22-80). At the early stage of learning to solve the Tower of Hanoi puzzle, speed and efficiency were associated with age, prefrontal cortex volume, and working memory. A similar pattern of brain-behavior associations was observed with perseveration measured on the Wisconsin Card Sorting Test. None of the examined structural brain variables were important at the later stages of skill acquisition. When hypertensive participants were excluded, the effect of prefrontal shrinkage on executive aspects of performance was no longer significant, but the effect of working memory remained. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Giuseppe Curr Marco Camalleri Denise Calì Francesca Monforte Fortunato Neri 《Microelectronics Reliability》2007,47(4-5):819
A detailed study of the interface state properties shown by the silicon/oxynitride/oxide gate layers used in Vertically Diffused PowerMOSFET (PowerVDMOS) technologies is reported. A quantitative analysis of interface states versus the specific N2O based nitridation process, extracted from current–voltage characteristics in depletion regime, provided a clear trend and turns to be of great importance for reliability performances of the final device. 相似文献
87.
Walker Denise D.; Roffman Roger A.; Stephens Robert S.; Wakana Kim; Berghuis James 《Canadian Metallurgical Quarterly》2006,74(3):628
This study's aims were (a) to investigate the feasibility of a school-based motivational enhancement therapy (MET) intervention in voluntarily attracting adolescents who smoke marijuana regularly but who are not seeking formal treatment and (b) to evaluate the efficacy of the intervention in reducing marijuana use. Ninety-seven adolescents who had used marijuana at least 9 times in the past month were randomly assigned to either an immediate 2-session MET intervention or to a 3-month delay condition. Two thirds of the sample characterized themselves as in the precontemplation or contemplation stages of change regarding marijuana use. Participants' marijuana use and associated negative consequences were assessed at baseline and at a 3-month follow-up. Analyses revealed that both groups significantly reduced marijuana use at the 3-month follow-up ( p = .001); however, no between-group differences were observed. Despite the absence of a clear effect of MET, this study demonstrated that adolescents could be attracted to participate in a voluntary marijuana intervention that holds promise for reducing problematic levels of marijuana use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
Assertive community treatment (ACT) programs have made substantial strides in reducing inpatient hospitalizations and in improving the lives of individuals with a severe mental illness. However, few studies have investigated their effectiveness outside of a 24-month treatment period. The present study investigated treatment outcomes in an ACT program over a 36-month period. Results indicate that participants experienced a statistically significant reduction in hospital bed days during the first 2 years of treatment. Positive outcomes were demonstrated on other variables, including an increase in compliance with outpatient psychiatric appointments and a reduction in emergency outpatient contacts. Results indicate that clients and family members were satisfied overall with ACT services, but family members reported greater satisfaction than clients in all areas assessed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
Ahmed Hammami Denise Chang-Yen John A. Nighswander Ellen Stange 《Petroleum Science and Technology》1995,13(9):1167-1184
Asphaltene onset concentration and bulk deposition were measured for a typical live reservoir oil titrated with n-C6H14, n-C5H12, n-C4H10, C3H8, C2H6, CH4 and CO2 at 100° C (212 ° F) and 29.9 MPa (4340 psia). The concentration of titrant at asphaltene onset was observed to decrease approximately in a linear fashion with decreasing molecular weight of the paraffinic solvent; CH4 did not induce any asphaltene precipitation. Bulk deposition experiments were performed using a solvent: oil volume ratio of 10:1; the results indicated that the weight percent of asphaltenes precipitated increased exponentially with decreasing molecular weight of the paraffinic solvents. More importantly, the asphaltene molecular weight showed a maximum for n-C4H10 precipitated asphaltenes. Possible explanations for this unusual result are presented. 相似文献
90.
This study compared the sensitivity and teaching strategies of dysphoric and nondysphoric women working with unfamiliar 5- and 6-year-olds. Interactions of 20 dysphoric and 20 nondysphoric mothers and an unfamiliar child were observed during 2 classification tasks and 3 unstructured activities staged as breaks. Nondysphoric women were more sensitive to children's level of understanding than dysphoric women and were more likely to use a variety of teaching strategies. Dyads with nondysphoric women were also more likely to share decision making than dyads with dysphoric women. These differences between dysphoric and nondysphoric women were significant only in the structured classification tasks. The findings indicate that in some situations dysphoric and nondysphoric women vary in their sensitivity to children's cues and in the teaching strategies they use with children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献