The origin of the band at 1462 cm−1 generally appearing upon desorption of pyridine from acidic solids. Steps towards a more comprehensive understanding

The pyridine adsorption-desorption method, followed by IR spectroscopy, is generally applied for acidity determination of solid catalysts. A peculiar band at 1462 cm^–1 was observed by several authors upon pyridine desorption at higher temperatures and was interpreted in various ways. A new complex between Lewis framework acid sites and pyridine is proposed and several evidences are reported.     

Beta-gamma radiation from leaching resistant glasses containing uranium ions

The β and γ decay of uranium atoms from xUO₃(100 - x)[3B₂O₃ · MO] glass systems, where M=Sr or Pb and 0 ≤ × ≤ 20 mol%, is investigated. The γ decay data are very close to each other, for the same UO₃ contents, in both the systems. The composition dependence of the β decay exhibits a lower slope in the lead borate matrix than in the strontium borate matrix. The ratio between the β activity of samples with the same uranium ion concentrations in the two investigated glass systems is a function of the x values. The results are correlated with the amount of radioactive nuclides and with the structural environments of the radionuclides. The leaching treatment in water at temperatures below 100°C evidenced no aqueous dissolution of glass samples.     

Application of shape-memory alloys in nuclear power

Scientific-Research and Design Institute of Electrical Engineering, Special Office of Machine Design. Translated from Atomnaya énergiya, Vol. 79, No. 4, pp. 304–306, October, 1995.     

Inter-observer agreement in analysis of basal body temperature graphs from infertile women

In this study, we evaluated the reproducibility of analysis of basal body temperature graphs under optimized conditions for agreement. A total of 160 recordings were selected from spontaneous cycles of infertile women and analysed by three experienced clinicians using uniform criteria. Agreement at the various stages of analysis was assessed by the 'proportions of agreement' with 95% confidence intervals. Agreement in identification of the thermal nadir was clearly superior to that reported in previous publications. Reproducibility of 'ovulatory' graph features (i.e. biphasic graphs and adequate thermal shifts) was excellent. Agreement in classification of monophasic graphs and inadequate thermal shifts, although lower, was still good. Thus, with experienced observers and uniform criteria, a good agreement can be achieved in analysis of the most important parameters of the basal body temperature graph. We believe that an effort should be made to generalize the use of uniform analysis criteria, because only then can results from different institutions be compared and the remaining clinical evaluation of the method be performed.     

Gene regulation of trkB and trkC in the chick retina by light/darkness exposure

The trk gene family members; the neurotrophic receptors for neurotrophins, are implicated in the survival and the differentiation of neurons. The roles of these protooncogenes have been argued in the pathological conditions and in the specific developmental stage when the programmed cell death occurs to neurons. Here we studied a physiological role of the trk family members in the retina through observations of their gene regulation by light/darkness exposure. Northern blot analysis and immunohistochemistry demonstrate that trkB and trkC are up-regulated by light exposure and down-regulated by darkness in the rod/cone layer, the outer nuclear layer, and the ganglion cell layer. This physiological regulation suggests that these trk family members play a protective role from the damaging effect of light exposure in the retinal neurons.     

Construction of a parallel computational model by composition of computational facilities

We consider a general algorithm for constructing a parallel numerical model by composition of several computational objects. The only requirement for the applicability of the proposed algorithm is for the disturbance propagation speed to be finite. We present one possible approach to map a numerical model onto an object-oriented program model. Some results of numerical experiments on solving the heat conduction equation in linear and nonlinear cases are discussed.     

Numerical study of the anisotropy of wave responses from a fractured reservoir using the grid-characteristic method

This work is aimed at studying the problem of subsurface disturbance propagation in a massive rock containing various inhomogeneities: empty or filled cracks. Numerical solutions to the problems of wave propagation in such substantially inhomogeneous media have been obtained. The dependence that the parameters of the response from a fractured reservoir have on the problem parameters is studied. The latter parameters are the density of the crack location, the fractured reservoir extent, amount of cracks, the initial disturbance location, crack inclination, and disturbance frequency. The concept of response anisotropy is introduced and the dependence that the anisotropy has on the abovementioned parameters is studied.     

项目实训中的协同编程方法研究

在高职院校的软件项目实训环节中,大多项目需要团体协作进行编程。针对如果有效提高学生的协同编程效率、团队合作意识以及合作学习能力的问题,提出了基于Dillenbourg原则的协同编程方法。通过实践证明,该方法取得了良好的实训效果。     

Calculation of Settlers for Irrigation Systems

Power Technology and Engineering - This article describes a new method for calculating settlers for irrigation systems. The proposed method is based on the results of experimental research and...