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61.
Rositi Hugo Appadoo Owen Kevin Mestre Daniel Valarier Sylvie Ombret Marie-Claire Gadea-Deschamps Émilie Barret-Grimault Christine Lohou Christophe 《Multimedia Tools and Applications》2021,80(2):1945-1967
Multimedia Tools and Applications - Microsoft has recently released a mixed reality headset called HoloLens. This semi-transparent visor headset allows the user who wears it to view the projection... 相似文献
62.
Protein–polysaccharide complexes are used to improve protein stability and encapsulate high‐value ingredients, yet the influence of different salts on their formation has not been investigated. Using light scattering and turbidimetry, effects of chloride, sulphate and thiocyanate salts on β‐lactoglobulin and pectin complexes (protein/pectin ratio = 2:1 and 4:1) were determined in relation to effects of pH and ionic strength. Effects of anions on complex formation were significant at 25 mmol kg?1 added ionic strength. Cation effects were not significant. At 100 mmol kg?1 ionic strength, pH of complex formation increased with sulphate salts (pH 5.1) relative to chloride and thiocyanate salts (pH 4.9), while pH of coacervation increased with sulphate salts (pH 4.7) and decreased with thiocyanate salts (pH 4.4) relative to chloride salts (pH 4.6). Pure β‐lactoglobulin stability was otherwise reduced with thiocyanate salts below pH 5, implying a significant effect of pectin interactions. 相似文献
63.
64.
Informal settlements have become dominant forms and processes of urban development in many cities, yet the task of helping students engage with design issues in such contexts is fraught with difficulties of access, safety, and complexity. Drawing on detailed fieldwork, this article explores ways in which informal settlement formation can be taught in design studio through the use of games that simulate incremental practices of room-by-room accretion and prospects for transformation. The pedagogical goals are to effect a blurring of authorship and authority, to undermine top-down thinking, and to nourish forms of design imagination that unite process and form. 相似文献
65.
Primary Li-air cell development 总被引:1,自引:0,他引:1
Owen Crowther Benjamin MeyerMichael Morgan Mark Salomon 《Journal of power sources》2011,196(3):1498-1502
In the present communication, we report on recent researches for optimizing the performance of a primary organic-based Li-air cell. These researches focus on new processing technologies for a high capacity and high rate capable carbon cathode, and the development of oxygen selective membranes based on polysiloxane and methacrylate-polysiloxane copolymers. These membranes, generally classified as silicone rubbers exhibit high permeability for oxygen and impede water transport from the atmosphere into the Li-air cell and solvent loss from the cell into the atmosphere. 相似文献
66.
The paper introduces and supports the contention that an idiographic methodology is appropriate to the post- hoc study and interpretation of individual construction project cash flows. A cash flow model based on the logit transformation is proposed to be consistent with this methodology. The model is based on historical data, and yields two parameters to describe each individual project. The model is tested using two samples totalling 72 projects. Goodness of fit for the model, using a measure of standard deviation from 1.0% to 4.6%, with a median of 2.5%, is found for individual projects. The experimental hypothesis (that there is substantial variation between projects) is supported by the graphical and statistical evidence of deviation, which is argued to be the result of the individual ontology of each project - systematic error - rather than random error from an ideal. The paper concludes that forecasts of individual cash flows are invalid when derived from analysis of grouped data. 相似文献
67.
Claire D. Stevenson Andrew D. Ramsey Owen T. Nevin William Sinclair 《Landscape Research》2013,38(4):553-559
Abstract The grey squirrel Sciurus carolinensis is thought to have contributed to the decline of red squirrel S. vulgaris populations in the UK through resource competition and disease spread. This study used mtDNA sequencing to assess patterns of grey squirrel dispersal in the UK. Patterns of genetic variation within the dloop sequence were characterised for seven grey squirrel populations. Infiltration directions and potential barriers to dispersal are identified and discussed, with a focus on Cumbria, a county at the forefront of grey squirrel expansion. Understanding the dynamics of grey squirrel dispersal will aid their management at a landscape scale and enhance the conservation of red squirrels. 相似文献
68.
The refractive index study of copoly(arylene-siloxane)s constructed with amide, ester, or ether linkage units was conducted to synthesize a step-growth polymer for application in flexible displays. The copoly(arylene-siloxane) based materials have potential use in optical applications due to their durability, flexibility, and possession of good optical clarity properties when compared to conventional silica-filled polydimethylsiloxane-based materials. Measurement of refractive index (RI) was used as the main mode of analysis due to its direct correlation to optical clarity and material flexibility. Synthesis and characterization, including RI compiled data, was performed for six series of step-growth polymers. Effects of different linkage units, namely amides, esters, and ethers, adjacent to at least one six-membered cyclic unit (aromatic or aliphatic) were evaluated. It was observed that the refractive index of these polymers was directly proportional to the aryl content; however, the influence on RI was not equal across all types of linkage units. The highest RI copolymer, poly(4,4-methylenediphenyl diisocyanate-co-carbinol-terminated polydimethylsiloxane) (MDI-SD1.0k), yielded refractive index 1.470 and molecular weight (Mn) 16,100 g/mol; however, the copolymer poly(toluene-2,4-diisocyanate-co-carbinol-terminated polydimethylsiloxane) (TDI-SD) had the highest RI (1.462) per phenyl content. The 4,4-methylenediphenyl diisocyanate (MDI), toluene-2,4-diisocyanate (TDI), and hydrogenated methylenediphenyl-4,4-diisocyanate (HMDI) amide containing linkages best improved the refractive indices of the materials studied. 相似文献
69.
The modeling of the viscoelastic properties of semicrystalline polymeric matrix composites is discussed. Different mathematical models are applied to describe the development of the storage modulus, measured by dynamic mechanical analysis, as a function of the crystalline content during isothermal crystallization experiments. Best results are obtained with an empirical power law model developed in this work. The application of the Halpin-Tsai equation and of a theoretical model, based on a combination of parallel-series arrangements of viscoelastic elements representing the crystalline and amorphous phases, is also discussed. The main objective of this research is the comparison between experimental results obtained by differential scanning calorimetry and dynamic mechanical analysis during crystallization processes. 相似文献