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Positively-charged β-lactoglobulin derivatives prepared by amidation or esterification of available carboxyl groups of the native protein were bound strongly by casein micelles. Increasing amounts of these additives progressively decreased rennet coagulation time of casein micelles. Higher concentrations of positively-charged proteins coagulated casein micelles without addition of rennet extract. Of the modified proteins tested, approximately 1.0 g amidated β-lactoglobulin, 2.0 g ethyl-esterified β-lactoglobulin, or 1.0 g methyl-esterified β-lactoglobulin would be required to coagulate 100 ml of casein micelles at concentrations in milk. 相似文献
113.
Paola R. Souza Nina Paula Gonçalves Salau 《Chemical Engineering Communications》2019,206(11):1463-1473
AbstractIn the present work, kinetics of crystal violet (CV) adsorption on bentonite was studied by pore volume and surface diffusion model (PVSDM), surface diffusion model (SDM), and pore volume diffusion model (PVDM). The adsorption decay curves were obtained in batch system using different adsorbent dosages. The PVDM model did not interpreted the kinetic adsorption since the calculated value of Dp equal to 5.64?×?10?7 cm2 s?1 predicted a slower adsorption than that obtained by the experimental data. The PVSDM results indicates that the intraparticle diffusion is predominantly due to surface diffusion (93%) and the pore volume diffusion can be negligible. Once the surface diffusion was the limiting step, the estimation with one (Ds) and two (Dsq and α) parameters were tested in the SDM model. The statistical analysis revealed that the one-parameter SDM model was most appropriate to predict the CV adsorption on bentonite. The optimal values of Ds ranged from 6.19?×?10?10 to 6.49?×?10?10 cm2 s?1, and decrease with the adsorbent dosage. 相似文献
114.
Examines ritual as a tool for psychotherapeutic application with clients experiencing grief, trauma, anxiety, and family dysfunction. Case vignettes are provided to illustrate the therapeutic properties and creative power of rituals as interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
115.
Aal Konstantin Boulus-Rdje Nina Rohde Markus 《Computer Supported Cooperative Work (CSCW)》2022,31(2):149-157
Computer Supported Cooperative Work (CSCW) - 相似文献
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Marcela Achimovi?ová Francisco Jose Gotor Concepcion Real Nina Daneu 《Journal of Materials Science: Materials in Electronics》2012,23(10):1844-1850
Mechanochemical synthesis of bismuth selenides (BiSe, Bi2Se3) was performed by high-energy milling of bismuth and selenium powders in a planetary ball mill. The particle size distribution and the specific surface area of Bi/Se and 2Bi/3Se powder mixtures were analysed at increasing milling time. The products were characterized by X-ray diffraction, differential scanning calorimetry and transmission electron microscopy. The presence of bismuth selenide phases was observed after only 1?min of milling and full conversion into hexagonal BiSe phase (nevskite) and rhombohedral Bi2Se3 phase (paraguanajuatite) was reached after 10?min of milling. The nanocrystalline nature of both mechanochemically synthesised bismuth selenides was confirmed and their optical band gap energies were obtained on the basis of the recorded absorption spectra in UV–Vis spectral region. 相似文献
119.
Carla Gallardo Nina Holck Sandberg Helge Brattebø 《Building Research & Information》2014,42(3):343-358
The dynamics and metabolism of the built environment are important for understanding the construction, renovation and demolition activities that characterize its long-term physical development. Previous research on building stock development is limited, particularly for developing countries. As one of the most seismically active countries in the world, Chile's built environment is constantly subjected to losses. This study included earthquake vulnerability and damage in a dynamic material flow analysis (MFA) of the Chilean housing stock. Stock and flows of residential floor area were modelled using population and life style parameters. Demolition was modelled assuming a constant demolition rate. By characterizing the building stock according to vulnerability classes and establishing a mass balance per class, the effects of different typology distributions on the overall damage to the stock caused by earthquakes could be assessed. Scenarios with different trends in typology distribution for new construction and renovation suggest that significant potential exists for reducing future earthquake damage in the Chilean housing stock. This is best achieved by gradually reducing the vulnerability of buildings to earthquakes. Legislation, building standards and financial instruments could be used to ensure such reductions in earthquake damage and thereby provide socio-economic benefits in the future. 相似文献
120.
Matej Baláž Anna Zorkovská Javier S. Blazquez Nina Daneu Peter Baláž 《Journal of Materials Science》2017,52(20):11947-11961
Covellite, CuS and chalcocite, Cu2S nanoparticles prepared in the explosive manner from elemental precursors were further ball-milled in order to observe additional changes caused by mechanical action. Three phases of chalcocite were interchanging during milling, monoclinic one being major at the equilibrium after 30 min. In the case of covellite synthesis, milling for 15 min brought about a significant diminishment in the content of digenite, Cu1.8S, impurity. Covellite powder exhibited finer character than chalcocite, as documented by crystallite size, grain size and specific surface area analysis. Finally, the effect of milling speed on the explosive character of the reaction and phase composition of chalcocite was investigated. The most drastic conditions favored the formation of the monoclinic phase with the lowest symmetry and the time and intensity of the explosion was found to depend on the milling speed. The whole process is mechanically driven. 相似文献