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991.
992.
A Couette-type torsion wire surface shear viscometer was used to measure the apparent interfacial shear viscosity of pH 7
(I=0.05 M) buffered solutions of sodium caseinate in contact with sunflower oil. The sunflower oil contained 1% fat crystals
in either the β or β′ polymorphic form, or was crystal free. In all cases, the fat crystals increased the interfacial shear
viscosity synergistically, with the β′ crystals causing the biggest increase. Substituting the protein for a small-molecule
surfactant (Tween-40) showed that this was not simply due to the protein lowering the interfacial tension. Sedimentation studies
of the different fat crystal slurries suggested that the extent of the interfacial shear viscosity increase was related to
the strength of crystal-crystal interactions in the oil phase. It seems likely that when protein is present at the interface,
it fixes the adsorbed layer of fat crystals to the cross-linked protein film at the interface. When this film was sheared,
the strength of the crystal-crystal interactions in the oil phase became important. However, when Tween-40 was in the aqueous
phase instead of the protein, the crystal-crystal interactions were not relevant, presumably because the Tween-40 interfacial
film simply flowed around the adsorbed crystals 相似文献
993.
The empirical focus is two small adjacent estates in West Newcastle; one with a mostly Bangladeshi population, the other white. The contrasts between them form the basis for a discussion of low housing demand and high turnover; forms of social exclusion; community and ethnicity. The Bangladeshi population experience exclusion from housing. Their estate has high demand and low turnover. Their housing options are highly constrained by a combination of low income and fear of crime and harassment. On the other hand they are comparatively well integrated into the local economy and a strong community structure. In contrast, the white population has more housing choice as a result of low demand, but exhibit greater exclusion from the labour market and from 'civil society'. Recent proposals to restructure the housing of the West End could increase housing opportunities for the Bangladeshis, but their impact on the white estate is more uncertain. 相似文献
994.
Andrew Churchill 《Information Security Technical Report》2009,14(3):131-137
In recent years the repeated compromise and loss of personal information, from a variety of sources, both public and private, have led to the issue of privacy being increasingly in the public eye. Concurrently public policy developments in line with the UK's Transformational Government agenda have led to ever greater amounts of personal information being made available electronically, and with greater levels of access being explored in order to exploit greater efficiencies in the delivery of public services. Such a rise in both public concern of the security of their data and the levels of access being afforded to improve efficiency has sometimes been seen as dichotomous. This article looks at some of these underlying concerns to suggest some of the issues that need to be addressed when considering privacy in a public policy context, and examines the dangers of retrofitting privacy as an afterthought, and hence the importance of privacy by design. 相似文献
995.
Water Resources Management and Integrated Water Resources Management (IWRM) in Cameroon 总被引:2,自引:2,他引:0
Andrew Ako Ako Gloria Eneke Takem Eyong George Elambo Nkeng 《Water Resources Management》2010,24(5):871-888
Cameroon is blessed with abundant water resources. Rapid population increase, unplanned urbanisation, intensive industrial
and socio-economic development have led to poor and unsustainable management of these resources. Integrated Water Resources
Management (IWRM) is a promising approach in ensuring sustainable management of Cameroon’s water resources. It entails management
of water for various purposes and not for a single purpose which therefore involves different stake holders aiming at achieving
sustainable water resources management. This paper seeks to evaluate recent efforts to implement in IWRM in Cameroon by examining
the institutional framework for IWRM in Cameroon, conditions for the implementation of IWRM and proposes reforms for improving
IWRM in Cameroon. The paper concludes that reforms such as public participation at local council levels, recognition of water
as both an economic and a social good, putting IWRM within the larger context of Integrated Natural Resource Management (INRM)
and the exploitation of mathematical models within hydrological basins will improve IWRM in Cameroon. 相似文献
996.
997.
Richard D. Chambers John Hutchinson Noel M. Kelly Andrew K. Joel Anthony J. Rees Peter T. Telford 《Israel journal of chemistry》1999,39(2):133-140
Using peroxide, γ-, and UV-irradiation, free radical addition reactions of hexafluoropropene to diethers and to 18-crown-6 have been investigated and mono-, di-, and poly-adducts have been obtained. Factors influencing these additions, especially polar characteristics of intermediate radicals, have been elucidated. Adducts of 18-crown-6 retain a capacity to complex to alkali-metal ions. 相似文献
998.
D Reddy AS Pollock SA Clark K Sooy RC Vasavada AF Stewart T Honeyman S Christakos 《Canadian Metallurgical Quarterly》1997,94(5):1961-1966
999.
G. Roger Fenwick E. Ann Spinks Andrew P. Wilkinson Robert K. Heaney Maurice A. Legoy 《Journal of the science of food and agriculture》1986,37(8):735-741
The effects of dry extrusion of mixtures of rapeseed and soya bean on total and individual glucosinolates, selected glucosinolate hydrolysis products, myrosinase, sinapine and tannins have been compared with those of more conventional processing, e.g. lime treatment, micronisation and ammoniation. Extrusion at 150°C effectively inactivated myrosinase but had relatively little effect on glucosinolate content unless chemicals were added before extrusion; the most effective combination, 5% alkali+1% ferrous sulphate, reduced the total glucosinolate content by 80%. Under the latter conditions very high (>30 μmol g?1 defatted meal) levels of nitriles were produced, leading to the suggestion that nitriles in addition to oxazolidine-2-thione and isothiocyanates be used to monitor the effectiveness of processing techniques. None of the extrusion conditions showed any significant effect on reducing sinapine or tannin contents. In view of the chemical data presented, and the probable adverse effects which the processing conditions selected have on the nutritional value of the processed meal it seems unlikely that extrusion will play a significant role in rapeseed detoxification. 相似文献
1000.
A widespread assumption in theories of emotion is that there exists a small set of basic emotions. From a biological perspective, this idea is manifested in the belief that there might be neurophysiological and anatomical substrates corresponding to the basic emotions. From a psychological perspective, basic emotions are often held to be the primitive building blocks of other, nonbasic emotions. The content of such claims is examined, and the results suggest that there is no coherent nontrivial notion of basic emotions as the elementary psychological primitives in terms of which other emotions can be explained. Thus, the view that there exist basic emotions out of which all other emotions are built, and in terms of which they can be explained, is questioned, raising the possibility that this position is an article of faith rather than an empirically or theoretically defensible basis for the conduct of emotion research. This suggests that perhaps the notion of basic emotions will not lead to significant progress in the field. An alternative approach to explaining the phenomena that appear to motivate the postulation of basic emotions is presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献