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991.
Bor‐Sen Chiou George H. Robertson LuAnn E. Rooff Trung Cao Haani Jafri Kay S. Gregorski Syed H. Imam Greg M. Glenn William J. Orts 《应用聚合物科学杂志》2010,116(5):2638-2644
Wheat gluten films of various thicknesses formed at 30–70°C were treated with cold sulfuric acid to produce sulfated gluten films. Chemical, thermal, thermal stability, and water uptake properties were characterized for neat and sulfated films. The sulfated gluten films were able to absorb up to 30 times their weight in deionized water. However, this value dropped to 3.5 when the film was soaked in a 0.9% (w/w) NaCl solution. The films were also soaked 4 times in deionized water, and each soaking resulted in a reduced water uptake capacity. The temperature of film formation had no effect on the final water uptake properties. Also, thinner films had higher concentrations of sulfate groups than thicker films; this resulted in higher water uptake values. In addition, sulfated gluten films had comparable glass‐transition temperatures but lower thermal stabilities than the neat gluten films. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
992.
Decorative coatings require not only an attractive appearance for market applications, but also an ability to protect the surface underneath. Because of this, corrosion, wear and their combined effects (termed tribocorrosion) are particularly important for lifetime prediction. In this paper, the tribocorrosion behaviour of a range of single layered titanium oxycarbide, TiCxOy, coatings, produced by DC reactive magnetron sputtering, has been studied and reported as a function of electrode potential and applied load. The study was conducted in a reciprocating sliding tribo-system (Plint TE 67/E) in a bio-fluid (an artificial perspiration solution) at room temperature. During the wear tests, both the open-circuit potential and the corrosion current were monitored. The results showed that electrode potential and load have a significant influence on the total material loss. The variations in Rp (polarization resistance) and Cf (capacitance) before and after sliding, obtained by Electrochemical Impedance Spectroscopy (EIS) were evaluated in order to provide an understanding of the resistance of the film in such conditions. Tribocorrosion maps were generated, based on the results, indicating the change in mechanisms of the tribological and corrosion parameters for such coatings, as a function of load and applied potential. 相似文献
993.
This paper presents a systematic literature review of studies investigating the extent and the ways in which health claims influence consumers. It focuses on published international research on health claims from US, Australia, Canada, Brazil and European countries. Research papers (n = 42) that were identified were coded in terms of sample type, research objectives/questions, research design and methodological details, as well as results and implications for future research. Results provide a systematic overview of the context in which health claims have been examined in the past and present a synthesis of findings in six thematic categories, namely knowledge/awareness of dietary issues, effects of health claims on purchase decisions, effects of health claims on perception/attitudes/beliefs, sources of information and trust, framing of health claims and disease-risk reduction and health-enhancing claims as well as consumer purchase decision. 相似文献
994.
Energy conservation in buildings is greatly influenced by natural daylight in tropical region. A vital step towards development
and promotion of daylighting technology in buildings is a prior study on estimation of exterior daylight availability for
illuminating its interiors. In view of this, the present communication depicts the preliminary work progress carried out to
arrive at a comprehensive idea on assessment of daylight availability and its characteristics. The study is reported taking
the representative case of Bangalore (India) (latitude 12.97° N, longitude 77.56° E),which in future work facilitates to device
suitable interior illuminance models and lighting controls for a daylight-artificial light integrated scheme. The objective
of this paper is to document the estimation of spatial exterior daylight parameters like exterior horizontal as well as vertical
global and diffuse daylight illuminance in addition to their respective luminous efficacies computed using an established
analytical model. The paper also highlights user friendly computer simulation tool developed, for the detailed estimation
of daylight availability at a particular region by the inclusion of corresponding solar radiation data. 相似文献
995.
The efficient prediction of the nonlinear dynamic response of structures with uncertain system properties poses a major challenge in the field of computational stochastic mechanics. In order to investigate realistic problems of structures subjected to transient seismic actions, an efficient approach is introduced. The presented methodology is used to assess the response of a steel frame modeled with a mixed fiber-based, beam–column element. The adopted modeling provides increased accuracy compared to traditional displacement-based elements and offers significant computational advantages for the analysis of systems with stochastic properties. The uncertain parameters considered are the Young’s modulus and the yield stress, both described by homogeneous non-Gaussian translation stochastic fields. The frame is subjected to natural seismic records that correspond to three levels of increasing seismic intensity as well as to spectrum-compatible artificial accelerograms. Under the assumption of a pre-specified power spectral density function of the stochastic fields that describe the two uncertain parameters, the response variability is computed using Monte Carlo simulation. A parametric investigation is carried out providing useful conclusions regarding the influence of different non-Gaussian distributions (lognormal and beta) and of the spectral characteristics of the stochastic fields on the response variability. 相似文献
996.
997.
998.
George Marsh 《Refocus》2001,2(6):18
Despite being one of the world's windiest nations, UK is only eighth in terms of installed wind turbine capacity, with 400MW on stream (by the year 2000). In comparison Germany (6000), USA (2500), Spain (2000) and Denmark (2200) all had installed capacities well in excess of the UK total. UK has had a particular problem with public acceptance and approvals for onshore sites, but now that attention throughout much of densely-populated north western Europe is turning offshore, British enterprise may have another chance to achieve global scale and enhance the country's international position in exploiting this sustainable resource. Is, however, its industry in a position to seize the moment? There may be some doubt since there are few indigenous companies producing the turbines and blades that are key, though a number of lead overseas players have established a presence here. George Marsh, Refocus magazine, takes a closer look. 相似文献
999.
The relative contribution of serotonin (5HT) neurotransmission within the medulla (rostral ventromedial medulla) and forebrain (amygdaloid central nucleus and nucleus parafascicularis thalami) to the antinociceptive action of morphine microinjected into the ventrolateral periaqueductal gray (vPAG) was evaluated. The 5HT receptor antagonist methysergide was microinjected into the medulla, forebrain, (or both) after injection of morphine into the vPAG. The contribution of 5HT to the antinociceptive action of morphine was observed to depend on (a) the dose of morphine administered into the vPAG, (b) the site(s) at which methysergide was administered, and (c) the level of the neuraxis at which the behavioral assay was organized. Results of the present study were combined with those of previous studies from this laboratory and presented as a model of the mechanisms by which morphine administered into the vPAG generates its antinociceptive action. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
George TSIRPANLIS Fotini BOUFIDOU Margarita ZOGA George TRIANTAFYLLIS Alexandra FATOUROU Kyriaki STAMATELOU Aliki BLETA Christiana PETRIHOU Stylianos CHATZIPANAGIOTOU Chrysoula NICOLAOU 《Hemodialysis international. International Symposium on Home Hemodialysis》2009,13(2):197-204
Low and not high cholesterol seems to predict high mortality in hemodialysis (HD) patients. The confirmation of this reverse epidemiology as well as its possible interconnection with the increased inflammatory activity observed in this population is being explored in the present study. A group of 136 HD patients was prospectively studied for 2 years, and cardiovascular disease (CVD) as well as all-cause mortality and morbidity were recorded. Baseline lipid profile, inflammatory status, and patients' characteristics were studied as potential survival and hospitalization predictors. During the 24-month follow-up, 21 deaths (52.4% due to CVD) and 38 hospitalizations (55.3% due to CVD) were recorded. In multivariate Cox regression analysis, decreased interleukin-10 (IL-10) and decreased total serum cholesterol (TChol) were the only independent predictors of CVD mortality while C-reactive protein and decreased TChol predicted all-cause mortality. Interleukin-10 at baseline was 11.29 ± 21.49 vs. 5.51 ± 4.57 pg/mL (P<0.018) and TChol 167.37 ± 47.84 vs.122.04 ± 26.48 mg/dL (P<0.000) in survivors vs. nonsurvivors from CVD, while C-reactive protein at baseline was 9.37 ± 11.54 vs. 23.15 ± 18.76 mg/L (P<0.000) and TChol 169.26 ± 46.42 vs. 133.26 ± 46.33 mg/dL (P<0.003) in survivors vs. nonsurvivors from any cause of death. Using the same method of statistical analysis, IL-6 and decreased soluble gp130 (sgp130)—an antagonist of IL-6 action—were found to be the only independent prognostic factors for hospitalization due to CVD while decreased soluble gp130 remained the sole predictor of hospitalization due to any cause. In conclusion, reverse epidemiology regarding cholesterol is confirmed in the present study. Furthermore, inflammatory activity also predicts, independently of or in conjunction with low-cholesterol, CVD and all-cause morbidity and mortality in HD patients. 相似文献