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91.
Monomeric formaldehyde and the cyclic oxymethylenes tetraoxane and pentaoxane were retained by cotton to similar extents at the high temperatures used in textile finishing, but the mechanisms of absorption appeared to differ. Trioxane, however, was not retained by cotton. The absorption of cyclic oxymethylenes did not seem to involve bonding to cellulose by primary valence bonds. The presence of other substances had a greater effect on the absorption of monomeric formaldehyde than of cyclic oxymethylenes, but changes in extent of absorption were not large enough to influence textile properties of treated fabric. 相似文献
92.
The current impetus for peer review had its origin in issues of cost containment, bolstered by intentions to improve quality of service. Peer review is usually conceived of as a way to either police a profession by ridding it of the few "bad actors" or to assure that services delivered meet minimum standards. The present article argues, however, that a more useful philosophy of peer review is to assume that it is at the heart of the definition of a profession. (2 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
A computational method of temperature distribution calculation for building elements in two- and three-dimensional time-dependent heat flow problems is developed with a general approximate solution using, as a numerical approach, the finite difference method. An analytical evaluation method of the accuracy of calculations is developed. The method described was compared with experimental values and good correspondence was obtained. The time-dependent study which is presented includes thermal resistance and inertia (heat capacity) of the components' materials and different geometric compositions. 相似文献
94.
95.
We report generation of broadly tunable (2.5-4 μm), narrow-band (0.04-0.35 cm-1) pulsed infrared radiation through a nanosecond optical parametric amplifier based on potassium titanyl phosphate (KTP) pumped by the second harmonic of a 10-Hz Nd:YAG laser. Input radiation at signal wavelengths of 615-662 nm was derived from a pulsed tunable dye laser system. Advantages of this device are simplicity, the broad range of infrared wavelengths to which a single dye in the dye laser provides access, and conversion efficiencies >10% at modest levels (<150 μJ) of input radiation. 相似文献
96.
NE Taylor RN Rosenthal B Chabus S Levine AS Hoffman J Reynolds L Santos I Willets P Friedman 《Canadian Metallurgical Quarterly》1993,15(1):36-40
Cryptococcal meningitis has a high mortality rate of central nervous infection. The patients usually die of the disease itself, or complications from increased intracranial pressure. Early diagnosis and treatment, including surgical drainage, will improve the results. In this series, twenty-one patients with high intracranial pressure (ICP > 300 mmH2 O) are presented. Fourteen received implantation of Ommaya reservoir to aspirate cerebrospinal fluid (CSF) for relief of symptoms of ICP. Meanwhile 4 of these 14 patients also received intraventricular injection of amphotericin B because of poor response to systemic drugs. Another seven patient received systemic drug therapy only. Survival during therapy occurred in 11 of 14 patients in the surgical group, compared with only 1 of 7 patients treated by drug therapy alone (P = 0.019). In the 14 patients who received implantation of an Ommaya reservoir, there was one complication of CSF leakage when the reservoir ruptured because of repeated aspiration. For patients with cryptococcal meningitis with high ICP, early implantation of an Ommaya reservoir will improve the survival rate. 相似文献
97.
Andrew C.E. Reid Stephen A. Langer Rhonald C. Lua Valerie R. Coffman Seung-Ill Haan R. Edwin García 《Computational Materials Science》2008,43(4):989-999
One way of computing the macroscopic behavior of a material sample with complex microstructure is to construct a finite element model based on a micrograph of a representative slice of the material. The quality of the results produced with such a model obviously depends on the quality of the constructed mesh. In this article, we describe a set of routines that modify and improve the quality of a 2D mesh. Most of the routines are guided by an effective element “energy” functional, which takes into account the shape quality of the elements and the homogeneity of the elements as determined from an underlying segmented image. The interfaces and boundaries in the image arise naturally from the segmentation process. From these routines, we construct a close-to-automatic mesh generator that requires only a few inputs, such as the linear sizes of the largest and smallest features in the micrograph. 相似文献
98.
Aspect-oriented programming (AOP) seeks to improve software modularity via the separation of cross-cutting concerns. AOP proponents often advocate a development strategy where programmers write the main application (base code), ignoring cross-cutting concerns, and then aspect programmers, domain experts in their specific concerns, weave in the logic for these more specialized cross-cutting concerns. This purely oblivious strategy, however, has empirically been shown to tightly couple aspects to base code in many cases, hindering aspect modularity and reuse. In essence, the more intricate the weaving between the cross-cutting concern and the base code (lexically and/or semantically), the harder it becomes to: (a) robustly specify how to weave the aspects in at the required points, (b) capture interactions between aspects and base code, and (c) preserve the correct weaving as the base code evolves.We propose an alternate methodology, termed cooperative aspect-oriented programming (Co-AOP), where complete lexical separation of concerns is not taken as an absolute requirement. Instead, cross-cutting concerns are explicitly modeled as abstract interfaces through explicit join points (EJPs). Programmers specify where these interfaces interact with base code either through explicit lexical references or via traditional oblivious aspects. This explicit awareness allows base code and aspects to cooperate in ways that were previously not possible: arbitrary blocks of code can be advised, advice can be explicitly parameterized, base code can guide aspects in where to apply advice, and aspects can statically enforce new constraints upon the base code that they advise. These new techniques allow aspect modularity and program safety to increase, and bring us towards a cooperative AOP paradigm.We illustrate our methodology via an example on transactions, and also give an initial evaluation of cooperative AOP through an empirical study on program extensibility comparing both the traditional and cooperative AOP methodologies. Initial results show that cooperative AOP techniques result in code that is less complex with lower overall coupling, facilitating extensibility. 相似文献
99.
Dillon S.M. Kerner T.E. Hoffman J. Menz V. Li K.S. Michele J.J. 《IEEE engineering in medicine and biology magazine》1998,17(1):95-108
Optical mapping of cardiac electrical activity is a valuable technique for studying arrhythmias, particularly the effects of defibrillation shocks. This technique has been exclusively applied to in-vitro preparations of hearts or tissues removed from an animal. But verification of experimental results and hypotheses is ideally performed in vivo on the heart as it remains in place in the animal. However, in-vitro optical mapping instrumentation and techniques cannot be easily applied in vivo. This article describes a system the authors developed to address this problem 相似文献
100.
We have observed seven infrared laser transitions when exciting a He discharge in a silver hollow cathode. To our knowledge, five of the seven laser transitions have not been reported previously in the literature. 相似文献