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Reid D.T. McGowan C. Ebrahimzadeh M. Sibbett W. 《Quantum Electronics, IEEE Journal of》1997,33(1):1-9
We describe the design and operation of a critically phase-matched femtosecond optical parametric oscillator based on KTA. By employing a small pump-signal noncollinear angle, tuning of the idler to beyond 4 μm is achieved using a Ti:sapphire pump laser. A Gaussian-beam model is described which can be used to identify the optimal noncollinear phase-matching geometry. Idler and signal pulses are characterized fully both temporally and spectrally and interferometric autocorrelation data at 3.5 μm showing idler pulses of only eight optical cycles duration are presented 相似文献
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CJ Reid 《Canadian Metallurgical Quarterly》1993,7(3):327-328
The results of a retrospective study of routine measurement of haemoglobin at the examination of one-year-old children at Gr?land mother and child clinic during 1989-91 showed that 37% of the children had anaemia. There was no difference between immigrants and the European population. There was no correlation between anaemia and sex in either of the population groups. This may imply that routine haemoglobin measurement should be generally introduced as part of the regular control of one-year-old children. 相似文献
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P M Reid A E Wilkinson K C Leung M N Jones 《Computer applications in the biosciences》1989,5(2):133-135
Analytical ultracentrifugation is commonly used for the determination of molecular weights (sedimentation equilibrium) and sedimentation coefficients (sedimentation rate) of biological macromolecules in solution. A Turbo Pascal program for the analysis of sedimentation equilibrium centrifugation data produced by absorbance optical systems is described. The user may enter data from a scan of absorbance versus distance from the centre of rotation, via a graphics tablet (or ASCII file). This is subsequently manipulated to yield an apparent weight average molecular weight for the given sample. Plots of ln (absorbance) versus (radius2) may also be produced. The method described uses readily available computational equipment requiring only a graphics tablet in addition to an IBM PC compatible computer. This technique and the software developed have been used to investigate the molecular weight range of two International Humic Substances Society (IHSS) reference samples from the Suwannee River. 相似文献
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As a step towards the construction of a comprehensive model for damaged composites, the deformation of transversely cracked laminates is analysed. The approach is based on a generalised plane strain approach and uses the finite strip method which allows general lay-ups of laminates rather than just cross-ply to be considered. General loading is treated. In addition, the method permits a more flexible control to be exercised between accuracy and the extensiveness of the calculations than can be achieved using existing analyses. This method could be integrated with the finite element analysis of structures to allow for changes in the effective material properties of locally damaged regions. Results produced by the approach are compared with those available in the literature and good agreement is demonstrated. 相似文献
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Furnace grown gate oxynitride using nitric oxide (NO) 总被引:4,自引:0,他引:4
Okada Y. Tobin P.J. Reid K.G. Hegde R.I. Maiti B. Ajuria S.A. 《Electron Devices, IEEE Transactions on》1994,41(9):1608-1613
Gate oxynitride was grown in NO for the first time. This approach can provide a tight N accumulation near the Si/SiO2 interface. Much lower thermal budget is required for an NO process than for an N2O process to produce an oxynitride with useful properties. Submicron MOSFET's with NO oxynitride showed superior current drive characteristics and comparable hot carrier immunity to those with N2O oxynitride 相似文献
9.
This article addresses several issues and trends relevant to the instruction of the learning disabled (LD). Although the concept of LD has received some support as a diagnostic category, limited data exist that demonstrate the effect of different instructional methods on the academic deficits of LD students. In this review, attempts to remediate LD are examined according to the adequacy of the theoretical context that guides the instruction and the efficacy and validity of the remediation procedures. Selected studies representative of medical, psychoeducational, neuropsychological, behavioral, linguistic, and cognitive treatment approaches are reviewed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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