A diamond-based photovoltaic cell

A photovoltaic cell based on a p–i synthetic-diamond structure was investigated. This bilayer structure consists of a substrate, which was grown by the high pressure–high temperature (НРНТ) method at an increased pressure and elevated temperature of highly-boron-doped p-type diamond, and on which a IIа-type film with a thickness of ~50 μm was deposited using the chemical vapor deposition (CVD) technique. Solid contacts were applied to the substrate, while the contacts that were applied to the CVD film were both solid and semitransparent. The current–voltage characteristics of photovoltaic cells for α, X-ray, and UV radiations for solid and semitransparent contacts were investigated. The obtained experimental data were used to evaluate the upper bound of the energy-conversion efficiency for all these radiations, which amounted to 4.5–14%.     

Thermodynamic analysis of equilibria in Fe-Cr-C alloys and evaluation of their dusting stability in aggressive carboniferous atmospheres

Thermodynamic analysis of phase transformations and reactions in Fe-Cr-C alloys is carried out with allowance made for all possible states, both stable and metastable, in the temperature range of metal dusting in aggressive carboniferous atmospheres. The results are compared with data on the corrosion resistance of chromium steel pipes under oil refining conditions. It is shown that, at high temperatures, one of the equilibrium phases in this system is the cementite solid solution (Fe_1-y Cr_y)₃C. Below 930 K, this phase becomes unstable to the decomposition into mixtures containing other carbides, but the tendency for chromium to stabilize cementite persists. The metal dusting mechanism changes in the composition range 0.03 y 0.055 (2.8–5.1 wt % Cr). This conclusion is supported by the results of tests on chromium steel (15Kh5M and 15Kh2M1) pipes under oil refining conditions, which indicate that the introduction of chromium into Fe alloys can only inhibit the degradation of Fe-Cr-C alloys under metal dusting conditions, without fully preventing it.Translated from Neorganicheskie Materialy, Vol. 41, No. 2, 2005, pp. 177–184.Original Russian Text Copyright © 2005 by Alshevskii, Baklanova, Zaitsev, Maltsev, Rodionova, Rybkin, Shaposhnikov.     

Influence of fluorine-containing substituents on the energy of intermolecular interactions and the heat of evaporation of disperse azo dyes

The heats of evaporation of some fluorine-containing disperse azo dyes have been determined by electronic absorption spectroscopy. The introduction of fluorine or fluorine-containing substituents into azo dye molecules decreases the energy of intermolecular interactions and correspondingly the heat of evaporation of dyes by 10–40 kJ mol^?1 as compared with dyes without fluorine. Such dyes may therefore be recommended for gas-phase methods of dyeing and printing. The energy of orientation-induction interactions is the main contribution to the heat of evaporation.     

Composition of clear petropolymer resins: Pyroplasts

Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 11, pp. 33–34, November, 1989.     

相变诱导塑性汽车用钢的发展现状与趋势

论述了相变诱导塑性(TRIP)钢的发展现状及其在汽车工业上的应用,重点讨论了 TRIP 效应的机理及TRIP钢性能的影响因素。介绍了2种采用新型工艺(低温贝氏体转变和淬火-碳分配工艺)的 TRIP 钢,并且通过对TRIP钢研究的最新数据,对比了2种工艺下TRIP钢的高速拉伸性能;最后对汽车用 TRIP 钢的研究方向进行了展望。     

Synthesis,structure, and properties of a bentonite–magnetite composite

A bentonite–magnetite composite is obtained by means of bentonite intercalation with iron oxide Fe₃O₄. Using the methods of electron microscopy, low-temperature nitrogen vapor adsorption–desorption, and XRD phase analysis, the composite morphology, structure, and texture have been investigated. It is shown that the synthesized bentonite–magnetite composite can be used as a sorbent for wastewater purification from organic pollutants.     

Use of Corrosion-Resistant Steels Alloyed with Nitrogen as a Bimetal Cladding Layer Prepared by Explosion Welding

Metallurgist - Research results are used to confirm the compatibility of workable chromium martensitic steels alloyed with nitrogen for a cladding layer and low-alloy steels as the base layer in...     

Irregular-waveguide elements coupling high-Q resonators with single-mode waveguides

A new type of element coupling a high-Q resonator with single-mode rectangular waveguides is proposed. The element is an irregular tapered section. A technique of electrodynamic calculation of such a coupling element is described. The element is experimentally investigated in the case of two-mirror open resonators. The high efficiency exhibited by the coupling element over a wide frequency band is confirmed by theoretical calculations and demonstrated experimentally.