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41.
DIALOG is a collection of routines, including a main ‘driver’ program, which is used by an applications programmer as the user interface to interactive applications programs. The routines handle command analysis, data input and editing, as well as processing standard commands such as HELP. DIALOG offers, with no extra effort from the applications programmer, not only a simple interface for first-time users which gives complete instruction in using the program, but also a ‘command driven’ interface for more experienced users. DIALOG permits the quick and effective production of interactive applications software by programmers with no previous experience of writing such programs. User reaction to the programs so far produced and offered as part of a university computing service has been extremely favourable. 相似文献
42.
Barley peptide hydrolase A acting on N-benzoyl-dl -arginine-p-nitroanilide as substrate is inhibited by the sulphydryl reagents N-ethyl maleimide and p-chloro-mercuriphenyl sulphonate. Oxidized glutathione, however, is non-inhibitory and several sulphydryl compounds are not stimulatory. Di-isopropylphosphofluoridate and 8-hydroxyquinoline also are effective inhibitors. The results are consistent with the presence of one or more exposed serine residues and a metal cation in the active centre, and one or more sulphydryl groups near the active centre of the enzyme. 相似文献
43.
The spectral response of a typical thin-film a-Si:H p–i–n solar cell has been investigated using the simulation RAUPV2. The peak in the external quantum efficiency has been observed to shift towards the violet part of the spectrum on decreasing the cell thickness. Moreover, the height of the peak increases as cell thickness is decreased. This is correlated with an enhancement in cell performance for thinner cells, due to a general increase in the drift field within the cell. The external quantum efficiency of a cell with an optimal concentration of phosphorous in the intrinsic layer has also been investigated. The external quantum efficiency for this cell is similar to that of the thinner cell, and is associated with the enhancement of the drift field near the p/i interface that is brought about by the phosphorous doping of the intrinsic layer. However, the integrated recombination for the thinner cell and the phosphorous-profiled cell differ significantly at long wavelengths, despite their similarity at shorter wavelengths. This effect is due to the weakening of the drift field near the n/i interface in the phosphorous-profiled cell. 相似文献
44.
Development of Aa New Time Temperature Indicator for Enzymatic Validation of Pasteurization of Meat Products
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This paper presents the development of a new smart time‐temperature indicator (TTI) of pasteurization whose operating principle is based on the complexation reaction between starch and iodine, and the subsequent action of an amylase on this complex causing its discoloration at a rate dependent on time and temperature of the medium. Laboratory simulations and tests in a manufacturing plant evaluated different enzyme concentrations in the TTI prototypes when exposed to pasteurization conditions. The results showed that the color response of the indicators was visually interpreted as adaptive to measurement using appropriate equipment, with satisfactory reliability in all conditions studied. The TTI containing 6.5% amylase was one whose best results were suited for use in validating the cooking of hams. When attached to the primary packaging of the product, this TTI indicated the pasteurization process inexpensively, easily, accurately, and nondestructively. 相似文献
45.
Enhancing third-grade student' mathematical problem solving with self-regulated learning strategies.
Fuchs Lynn S.; Fuchs Douglas; Prentice Karin; Burch Mindy; Hamlett Carole L.; Owen Rhoda; Schroeter Katie 《Canadian Metallurgical Quarterly》2003,95(2):306
The authors assessed the contribution of self-regulated learning strategies (SRL), when combined with problem-solving transfer instruction (L. S. Fuchs et al., 2003), on 3rd-graders' mathematical problem solving. SRL incorporated goal setting and self-evaluation. Problem-solving transfer instruction taught problem-solution methods, the meaning of transfer, and 4 superficial-problem features that change a problem without altering its type or solution; it also prompted metacognitive awareness to transfer. The authors contrasted the effectiveness of transfer plus SRL to the transfer treatment alone and to teacher-designed instruction. Twenty-four 3rd-grade teachers, with 395 students, were assigned randomly to conditions. Treatments were conducted for 16 weeks. Students were pre- and posttested on problem-solving tests and responded to a posttreatment questionnaire tapping self-regulation processes. SRL positively affected performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
S. Peng P. Jackson V. Sendijarevic K. C. Frisch G. A. Prentice A. Fuchs 《应用聚合物科学杂志》2000,77(2):374-380
Process temperature profiles of a two‐component rigid poly(urethane–isocyanurate) foam system were studied and compared with the predictions of a one‐dimensional numerical simulation. This model is based on experimentally determined thermophysical properties including thermal diffusivity, enthalpy of reaction, and rate of reaction. Temperature profiles were measured at three positions within the foam and at the foam surface for mold temperatures of 25°C and 55°C. A high rate of reaction and heat of reaction, along with low thermal diffusivity, cause temperatures near the foam center to be insensitive to mold temperatures for thick samples. Thermal analysis was used for determination of thermophysical properties. Temperature‐dependent heat capacity, reaction kinetics, and heat of reaction were evaluated using temperature‐scanning DSC. Thermal conductivity was analyzed from steady‐state heat profiles. The system reaction kinetics indicated much faster kinetics than reflected by process cure temperature profiles made using thermocouples. The simulations accurately predict experimental results, allowing determination of demold time dependence on process conditions, including feed temperature, mold temperature programming, and sample thickness. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 374–380, 2000 相似文献
47.
Chemical and physical characteristics of sheet-molded compounds were investigated using infrared and mechanical spectroscopies. Fourier transform infrared spectroscopy with photoacoustic detection facilitated surface analysis for determination of composition, depth profile, and thermal exposure effects. Dynamic mechanical spectroscopy utilized torsion, tension, and flexure modes to evaluate temperature and frequency-dependent viscoelastic properties. 相似文献
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CMV and other viruses down-regulate the cell surface expression of class I HLA, and while this allows them to evade CTL, it may make infected cells more susceptible to lysis by NK cells, due to the failure to engage class I inhibitory receptors on the NK cell. We studied CMV infection and found that fibroblasts infected with virus strains Towne, Toledo, Davis, and C1FE were refractory to NK lysis, while those infected with strains AD169, C1F, or R7 were susceptible. All viral strains down-regulated class I HLA to a similar extent, and we concluded that there was no evidence for any correlation between the latter and susceptibility to NK lysis. In contrast, there was a strong correlation between NK killing of CMV-infected cells and cell surface levels of lymphocyte function-associated antigen-3 (LFA-3). Fibroblasts infected with the Towne, Toledo, Davis, and C1FE strains of CMV down-regulated LFA-3 expression and were refractory to lysis, while strains AD169, C1F, and R7 up-regulated LFA-3 and were susceptible to NK killing. U373 MG (malignant glioma) cells expressed constitutively high levels of LFA-3 and were sensitive to NK lysis when infected with any of the above-listed CMV strains. We estimated that a minimum of between 29,000 and 71,000 LFA-3 molecules per target cell were needed for NK susceptibility. The effects on LFA-3 expression were due to immediate early/early viral gene products. We also demonstrated that fibroblasts infected with the strains Towne, Toledo, Davis, and C1FE expressed a ganciclovir-sensitive late CMV gene product, which delivered an inhibitory signal to NK cells. 相似文献