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81.
The dual-wall zirconia induction furnace consists of an inner susceptor tube and an outer insulation tube. The centre piece of the inner tube is coated with a thin silica film. The performance of the newly designed furnace was evaluated in terms of the strength of drawn fibres. The proof test of 47 km length of fibre demonstrated superb strength results, yielding the average survival length at 1·4 GN/m2 (200 klb in?2) to be ~8 km. 相似文献
82.
Sylvestre T. Schroeder J. Coen S. Emplit P. Haelterman M. 《Electronics letters》2008,44(21):1240-1242
A simple technique that allows for the repetition rate multiplication of optical pulse trains generated in passively modelocked fibre lasers is experimentally demonstrated. This is achieved by initiating higher-order passive modelocking by using both a dual-channel fibre Bragg grating and a Fabry-Perot filter inside the fibre cavity. Continuous dark pulse trains with a repetition rate of 60-GHz were generated, which is a four-fold multiplication of the Fabry-Perot free spectral range. 相似文献
83.
William F. Wright Edward D. Schroeder Daniel P. Y. Chang 《Canadian Metallurgical Quarterly》2005,131(7):999-1009
Transient loading of vapor-phase biofilters may result in exceedence of the local reaction or mass transfer capacity of the inlet region. In such cases, higher concentrations of contaminants are carried deeper into the bed where there is less active biomass and, in some cases, breakthrough of contaminants may occur. Previous studies have demonstrated that periodic reversal of the flow direction results in improved transient-loading response. However, quantitative information on the extent of the benefit is lacking. Step function increases in toluene concentration were applied to unidirectional-flow and flow-direction-switching laboratory reactors operated in parallel. Contaminant concentration was monitored at several points along the packed beds. Relative to unidirectional mode of operation, periodic flow reversal produced a more uniform distribution of microbial reaction capacity along the length of the packed bed. Directional switching at a 12-h interval did not result in a loss of activity or removal capacity. Mass-removal rates under transient-loading conditions were similar in the first-half of both biofilters but, in the second-half of the units, significant removals were observed only in the flow-direction-switching biofilter. As a result, maximum mass-removal rates under transient-loading conditions were approximately twice as great for the flow-direction-switching biofilter relative to the conventional unidirectional-flow biofilter receiving similar mass loading. 相似文献
84.
Di Bartolomeo A Giubileo F Santandrea S Romeo F Citro R Schroeder T Lupina G 《Nanotechnology》2011,22(27):275702
We discuss the origin of an additional dip other than the charge neutrality point observed in the transfer characteristics of graphene-based field-effect transistors with a Si/SiO2 substrate used as the back-gate. The double dip is proved to arise from charge transfer between the graphene and the metal electrodes, while charge storage at the graphene/SiO2 interface can make it more evident. Considering a different Fermi energy from the neutrality point along the channel and partial charge pinning at the contacts, we propose a model which explains all the features observed in the gate voltage loops. We finally show that the double dip enhanced hysteresis in the transfer characteristics can be exploited to realize graphene-based memory devices. 相似文献
85.
Robinette SL Ajredini R Rasheed H Zeinomar A Schroeder FC Dossey AT Edison AS 《Analytical chemistry》2011,83(5):1649-1657
Nuclear magnetic resonance (NMR) is the most widely used nondestructive technique in analytical chemistry. In recent years, it has been applied to metabolic profiling due to its high reproducibility, capacity for relative and absolute quantification, atomic resolution, and ability to detect a broad range of compounds in an untargeted manner. While one-dimensional (1D) (1)H NMR experiments are popular in metabolic profiling due to their simplicity and fast acquisition times, two-dimensional (2D) NMR spectra offer increased spectral resolution as well as atomic correlations, which aid in the assignment of known small molecules and the structural elucidation of novel compounds. Given the small number of statistical analysis methods for 2D NMR spectra, we developed a new approach for the analysis, information recovery, and display of 2D NMR spectral data. We present a native 2D peak alignment algorithm we term HATS, for hierarchical alignment of two-dimensional spectra, enabling pattern recognition (PR) using full-resolution spectra. Principle component analysis (PCA) and partial least squares (PLS) regression of full resolution total correlation spectroscopy (TOCSY) spectra greatly aid the assignment and interpretation of statistical pattern recognition results by producing back-scaled loading plots that look like traditional TOCSY spectra but incorporate qualitative and quantitative biological information of the resonances. The HATS-PR methodology is demonstrated here using multiple 2D TOCSY spectra of the exudates from two nematode species: Pristionchus pacificus and Panagrellus redivivus. We show the utility of this integrated approach with the rapid, semiautomated assignment of small molecules differentiating the two species and the identification of spectral regions suggesting the presence of species-specific compounds. These results demonstrate that the combination of 2D NMR spectra with full-resolution statistical analysis provides a platform for chemical and biological studies in cellular biochemistry, metabolomics, and chemical ecology. 相似文献
86.
87.
Schroeder Jennifer R.; Gupman Anne E.; Epstein David H.; Umbricht Annie; Preston Kenzie L. 《Canadian Metallurgical Quarterly》2003,11(3):195
Data from 2 contingency management trials, targeting opiate or cocaine use, were used to investigate whether noncontingent vouchers inadvertently reinforce drug use. The control group in each trial received noncontingent vouchers matched in value and frequency to those received by experimental groups, but independent of urinalysis. Vouchers were offered thrice weekly for 8 weeks (opiates) or 12 weeks (cocaine). Both dose-response and temporal associations of noncontingent voucher receipt with drug-positive urines were assessed. Drug use was unrelated to frequency of noncontingent voucher delivery and noncontingent voucher receipt when being drug positive was unassociated with risk of subsequent drug use, with one exception: cocaine use in the cocaine study (relative risk = 1.05, 95% confidence interval: 1.01-1.09). Overall, results do not indicate a causal relationship between noncontingent voucher receipt and increased drug use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
A lower bound to the limit pressure of a tee is based on three-dimensional stresses expanded in series which satisfy the equilibrium condition of branch and pipe automatically. The coefficients of the series are determined from the continuity condition of stress across the surface of intersection of branch and piping using partly the power series method and partly the point collocation least square method. The bounds are in agreement with experimental results of three limit pressure tests on tees conducted by the authors. The standard error calculated for the residuals of the overdetermined set of equations generated by the least square method is acceptable. However, high residuals at a few collocation points render the bounds too low for design if diameter ratios of the cylinders are smaller than 0.5 and a much more completed analysis is needed to improve this. 相似文献
89.
Schroeder Stephen R.; Schroeder Carolyn S.; Landesman Sharon 《Canadian Metallurgical Quarterly》1987,42(8):805
Reviews the 6 principles of Public Law 94-142 (the Education for All Handicapped Children Act)—including nondiscriminatory evaluation, the least restrictive environment, and individualized education—and discusses ways psychologists may be able to further the achievement of its effectiveness. Mental retardation psychologists provide an array of services, including prevention, consultation, training, education, supervision, administration, research, and consultation on individualized educational plans. Other potential areas for intervention include development of psychometric measures, social ecological assessment, and vocational education. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
M Belickova HW Schroeder YL Guan J Brierre S Berney MD Cooper JT Prchal 《Canadian Metallurgical Quarterly》1994,1(1):56-61
The Drosophila hairy gene encodes a basic helix-loop-helix protein that functions in at least two steps during Drosophila development: (1) during embryogenesis, when it partakes in the establishment of segments, and (2) during the larval stage, when it functions negatively in determining the pattern of sensory bristles on the adult fly. In the rat, a structurally homologous gene (RHL) behaves as an immediate-early gene in its response to growth factors and can, like that in Drosophila, suppress neuronal differentiation events. Here, we report the genomic cloning of the human hairy gene homolog (HRY). The coding region of the gene is contained within four exons. The predicted amino acid sequence reveals only four amino acid differences between the human and rat genes. Analysis of the DNA sequence 5' to the coding region reveals a putative untranslated exon. To increase the value of the HRY gene as a genetic marker and to assess its potential involvement in genetic disorders, we sublocalized the locus to chromosome 3q28-q29 by fluorescence in situ hybridization. 相似文献