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101.
102.
Mixed-matrix membranes (MMMs) were prepared by combinations of two different kinds of porous fillers [metal-organic frameworks (MOFs) HKUST-1 and ZIF-8, and zeolite silicalite-1] and polysulfone. In the search for filler synergy, the MMMs were applied to the separation of CO(2)/N(2), CO(2)/CH(4), O(2)/N(2), and H(2)/CH(4) mixtures and we found important selectivity improvements with the HKUST-1-silicalite-1 system (CO(2)/CH(4) and CO(2)/N(2) separation factors of 22.4 and 38.0 with CO(2) permeabilities of 8.9 and 8.4 Barrer, respectively). 相似文献
103.
Fleury BG Figueiredo L Marcoli MI Teixeira VL Ferreira AB Pinto AC 《Natural product communications》2011,6(5):667-672
The distribution of fatty acids in 13 species of macroalgae (Chlorophyta, Ochrophyta and Rhodophyta) and 1 seagrass (Spartina sp), collected on the Rio de Janeiro state coast was determined. The results were evaluated in search of correlations between the taxonomic and phylogenetic position of these macrophytes. Statistical analyses showed the effectiveness as taxonomic and phylogenetic markers of the distribution of the methyl fatty acid esters in these macrophytes. 相似文献
104.
J. Równicka-Zubik A. Sułkowska M. Maciążek-Jurczyk L. Sułkowski W. W. Sułkowski 《光谱学快报》2013,46(7):520-529
Sulindac (SDC) is a nonsteroidal anti-inflammatory drug, useful in the treatment of chronic and acute inflammatory conditions. The binding of SDC to human serum albumin and bovine serum albumin was studied by fluorescence spectroscopy and the results compared with those obtained for human and bovine serum albumin destabilized with urea and guanidine hydrochloride. SDC interacts with serum albumin within the hydrophobic subdomain IIA and/or IB. The analysis of the binding constants shows that the studied albumins preserve their binding capacity in the presence of destabilizing/denaturating agents. The denaturation coefficient has been calculated to estimate the degree of denaturation of protein. 相似文献
105.
106.
Adriana Vlez Feij Maria Alice Parente Mara Behlau Srgio Haussen Maria Cecília De Veccino Beatriz Castellar de Faria Martignago 《Journal of voice》2004,18(3):341-347
The objective is to investigate the presence of dysphonic symptoms in multiple sclerosis (MS) patients and to compare quantitative acoustic parameters in multiple sclerosis patients and normal individuals. The method of study was an 8-month controlled cross-sectional that was carried out with 106 individuals (30 MS, 76 controls). Both groups included males and females from 20 to 55 years. Exclusion criteria were prior vocal disorder, laryngeal microsurgery, recent endotracheal intubation, tumors, laryngeal, lung or mediastinal metastases, respiratory disease, and other associated neurological diagnoses. For dysphonic symptoms (qualitative variables), associations were assessed using Mantel-Haenszel's chi2 test, with Yates correction or the Fisher exact test when necessary. Statistical significance was set at p< or =0.05. Dysphonia was observed in 70% of MS individuals versus 33% of controls (p=0.01). Association was found between MS and dysphonia (OR: 2.2, CI 95%: 1.13-4.25). Fundamental frequency was higher among MS patients (p=0.01). Fundamental frequency deviation was significantly higher in MS women (but not men) than controls (p=0.00). Jitter was higher in MS men than in all other groups (p=0.00). Results suggest that evaluation and treatment of MS patients should be revised, evaluating voice alterations in relation to other signs. MS seems to intensify gender effect on fundamental frequency deviation, noise, and jitter, with MS women presenting fewer voice variations than men. 相似文献
107.
We give necessary and sufficient conditions on the wavelet coefficients of a function for being a member of some BMOφ (w) space. We achieve this characterization for a wide variety of wavelet systems. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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109.
This paper shows the results of underground waters last monitoring in the province of Lecce (Apulia, Southern Italy). We carried out the physical-chemical characterization of the aquifers and their classification in accordance to limit values sanctioned by Italian legislation in force, by European directives and by FAO, in order to define their quality and to establish their possible use for drinkable and irrigation purposes. The attention has been focused on salinity evaluation and underground waters contamination phenomena, due to sea-water intrusion and to the use of fertilizers. Salinity and nitrates concentrations are high in a few wells. Iron and manganese concentrations are very high for almost every sample and this is due to corrosion phenomena of artesian wells metallic structure. For a better interpretation of data, multivariate statistical analysis has been used, in order to obtain the correlation among analytical results, soils hydro-geological properties and anthropic conditions. 相似文献
110.
Fernandes AC Fernandes R Romao CC Royo B 《Chemical communications (Cambridge, England)》2005,(2):213-214
The high valent molybdenum-dioxo complex [MoO2Cl2] catalyzes the addition of dimethylphenylsilane to aldehydes and ketones to afford the corresponding dimethylphenylsilyl ethers in quantitative yield. 相似文献