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101.
Bronwyn Hanna 《Architectural Theory Review》2013,18(1):48-62
This biographical account of Winsome Hall Andrew is a largely chronological account of an early twentieth century NSW architect whose work deserves further serious evaluation. It is also a demonstration of biographical narrative as an strategy for bringing women into a particular kind of historical presence, stressing the complexity of social expectations of women as fundamental to an understanding of their public productivity. It is also a somewhat poignant story which depends upon the honesty and courage of Hall Andrew's friends and relatives in acknowledging the difficulties in her life as well as the niceties. Finally, it is presented as an example of the complex interpretative strategy of my PhD thesis, an attempt to be accessible, relevant, critical, honest and fair. 相似文献
102.
103.
Beech wood xylan, as a model substance for hemicellulose contained in plant biomass waste, was subjected to thermohydrolysis in subcritical water. The composition of the product fractions obtained as a result of its hydrothermal decomposition was studied: the water fraction, the oil fraction and the solid fraction of charred post-reaction residue. An increase in temperature favors xylan thermohydrolysis, leading to the production of saccharides – the products of its hydrolytic depolymerization. The yield of the saccharides contained in the water-soluble product fraction reaches it maximum value at 220 °C and 235 °C, with the retention time of 0 min. Both extending reaction time up to 30 min and further increasing the temperature favor the occurring of secondary reactions – saccharide decomposition – leading to the production, among others, of carboxylic acids, furfurals and aldehydes, and their further carbonization and gasification. 相似文献
104.
S. Fvrier D. Gaponov M. Devautour P. Roy L. Daniault M. Hanna D.N. Papadopoulos F. Druon P. Georges M.E. Likhachev M.Y. Salganskii M.V. Yashkov 《Optical Fiber Technology》2010,16(6):419-427
In the search for ever higher output power or energy from fibre oscillators or amplifiers a nowadays mature technology relies on enlarging the fibre mode area. Broadening of the core diameter, all other things being equal, inevitably yields a multimode fibre, thereby dramatically limiting the device usefulness. Various strategies have been deployed to design and manufacture single transverse mode fibre oscillators and amplifiers, among which making use of the so-called photonic bandgap effect to restrict the modal population seems promising. Helped by efficient and reliable numerical tools the design of large mode area singlemode photonic bandgap fibres is presented. Two fibres with 20-μm and 40-μm core diameter, both of them heavily doped with Yb3+ ions, have been fabricated by the widespread modified chemical vapour deposition process and are shown to behave properly when used as the core element of either continuous wave oscillators or femtosecond amplifiers. Good output beam quality (M2 parameter spanning from 1.12 to 1.5 for the set of fibres studied) and high slope efficiency of 80% in cw oscillation regime are demonstrated. Furthermore the 40-μm core diameter fibre is shown to be resilient to tight bending down to 7.5-cm radius. The stack-and-draw process makes it easy to tailor the outer cladding so that a large numerical aperture can be reached. Subsequently, from this air-clad fibre, 500 fs 47 W pulses at 35 MHz are obtained from a two-stage chirped pulse amplification system. 相似文献
105.
Pask H.M. Carman R.J. Hanna D.C. Tropper A.C. Mackechnie C.J. Barber P.R. Dawes J.M. 《IEEE journal of selected topics in quantum electronics》1995,1(1):2-13
Ytterbium-doped silica fibers exhibit very broad absorption and emission bands, from ~800 nm to ~1064 nm for absorption and ~970 nm to ~1200 nm for emission. The simplicity of the level structure provides freedom from unwanted processes such as excited state absorption, multiphonon nonradiative decay, and concentration quenching. These fiber lasers therefore offer a very efficient and convenient means of wavelength conversion from a wide variety of pump lasers, including AlGaAs and InGaAs diodes and Nd:YAG lasers. Efficient operation with narrow linewidth at any wavelength in the emission range can be conveniently achieved using fiber gratings. A wide range of application for these sources can be anticipated. In this paper, the capabilities of this versatile source are reviewed. Analytical procedures and numerical data are presented to enable design choices to be made for the wide range of operating conditions 相似文献
106.
107.
The extent to which simultaneous inputs in a three-dimensional (3D) auditory display mask one another was studied in a simulated sonar task. The minimum signal-to-noise ratio (SNR) required to detect an amplitude-modulated 500-Hz tone in a background of broadband noise was measured using a loudspeaker array in a free field. Three aspects of the 3D array were varied: angular separation of the sources, degree of correlation of the background noises, and listener head movement. Masking was substantially reduced when the sources were uncorrelated. The SNR needed for detection decreased with source separation, and the rate of decrease was significantly greater with uncorrelated sources than with partially or fully correlated sources. Head movement had no effect on the SNR required for detection. Implications for the design and application of 3D auditory displays are discussed. 相似文献
108.
K Hariharan G Braslawsky A Black S Raychaudhuri N Hanna 《Canadian Metallurgical Quarterly》1995,55(16):3486-3489
CTLs specific for tumor antigens play a major role in the immunity against cancer. We have shown that class I-restricted CTLs can be induced by injecting soluble antigens mixed in an antigen formulation (AF) that consists of squalane, Tween 80, and Pluronic L121 (S. Raychaudhuri et al., Proc. Natl. Acad. Sci. USA, 89: 8308-8312, 1992). In this study, using ovalbumin and the ovalbumin-expressing transfectoma (EG7) as a tumor model system, we examined the in vivo antitumor effect of antigen-AF mixture. Vaccination of mice with ovalbumin in AF 2 or 3 days after EG7 tumor challenge showed significant inhibition of tumor growth compared to mice vaccinated with ovalbumin in alum or in saline. Depletion of CD8+ cells at the time of immunization completely abrogated the AF-induced tumor protection, indicating that CD8+ T cells are the major effectors in tumor protection in vivo. Depletion of CD4+ cells led to a marginal loss of tumor protection, which may be the result of inhibition of ovalbumin-specific CTL response due to the lack of T-helper activity. Our results demonstrate that AF can be used in subunit vaccines to stimulate CTLs and tumor regression in vivo. 相似文献
109.
Sintering behaviour of ultrafine yttria-zirconia solid solution compacts, with yttria contents ranging between 4 and 10 mol % have been investigated and the microstructural developments during sintering were followed. The 4 mol % yttria-zirconia compacts sinter at 1200 ° C to a high density with a relatively fine uniform microstructure. Firing at 1400 ° C produces no improvement in densification and discontinuous grain growth develops. The lowest density values are obtained with the 10 mol % yttria-zirconia compacts, with clustering in the grains and greater porosity in the microstructure. The activation energies were determined for both 4 and 10 mol % Y2O3 -containing bodies in the temperature range 800 to 1000 ° C. 相似文献
110.
Inside Cover: Site‐Specific Modification of the Anticancer and Antituberculosis Polyether Salinomycin by Biosynthetic Engineering (ChemBioChem 14/2014)
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