一种多晶硅高温压力传感器

制作压力传感器时，在二氧化硅层上淀积多晶硅膜，既可利用优良的机械特性，又可保证压敏电阻与衬底间具有良好的绝缘性，由此可大大提高器件的温度特性。介绍了一种多晶硅压力传感器的原理和设计。实验结果表明，这类传感器具有灵敏度好，精度高等特点，电路工作范围为０－２５０℃，且具有良好的温度稳定性。     

UHF频段卫星移动通信系统若干问题的探讨

本文根据我国陆海空移动用户的需求与特点，借鉴国外经验，提出了建设ＵＨＦ频段卫星移动通信系统的建议；对照已建成的Ｃ波段卫星固定通信系统，分析了其优缺点；最后深入探讨了应用中的若干技术问题。     

Comparison of stimulated-emission-pumping fluorescence dip spectrometry and conventional fluorescence spectrometry in application to supersonic jet spectrometry

Summary A supersonic jet spectrum of 9,10-dichloroanthracene is measured by stimulated-emission-pumping fluorescence dip spectrometry and conventional fluorescence spectrometry. The performance obtained is compared for these spectrometric methods, providing same information concerned with the energy level of the ground state. The former is more preferential for measurement of a high-resolution spectrum, since the spectral resolution is determined by the linewidth of the dumping laser. On the other hand, the latter is more preferential for measurement with better sensitivity at the expense of the spectral resolution, since the fluorescence throughput can be improved by increasing the slit width of the monochromator.Dedicated to Professor Dr. Wilhelm Fresenius on the occasion of his 80th birthday     

Fractionation and composition of the carbohydrates of leaf vegetables

The qualitative and quantitative compositions of the carbohydrates of the leaf vegetables Lactuca sativa L., Spinacea oleracea L., and Rumex acetosa L. have been studied.M. V. Lomonosov Odessa Technological Institute of the Food Industry. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 349–351, May–June, 1993.     

An investigation of the membranotropic properties of the plant toxin thionin isolated fromPyrularia pubera

It has been shown by the ESR of spin probes that thionin initially interacts with with negatively charged membranes electrostatically and then passes into the membranes to a depth comparable with the length of the hydrophobic sections of the protein loops.Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent. Brigham Young University, Provo, Utah, USA. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 594–597, July–August, 1993.     

End unit effect on the Tg of differentiated series of perfluoro-poly (oxymethylene-co-oxyethylene) oligomers

Twelve series of linear oligomers of four different degrees of polymerization (x_n = 8.77−41.55), having a common perfluorinated random copolymeric chain as molecular body and two equal foreign end units of one of the types listed in Table 1, have been synthesized by derivatization of base samples of one of them having a diolic---CH₂OH functionality. The glass transition temperature T_g of all the series was measured and thus examined as a function of x_n. A clear end unit effect is observed, dominantly determined in every series by chemical nature and structure of the end units, quantitatively expressed at any x_n by different positive or negative T_g deviations from the common asymptotic T_g∞ value. The results are also discussed in terms of copolymer end effect and of relation between T_g and end copolymeric composition.     

Mechanical properties of polyester polymer-concrete

The properties of a polymer-concrete composed of polyester matrix and locally available rock aggregate are investigated. The formula of the concrete is found by an experimental-calculation approach in such a way as to attain a closer packing of the aggregate particles on the one hand, and to ensure the needed processing characteristics (placeability) of the mix on the other. It is shown experimentally that the material obtained has a rather high compression strength. Under prolonged compression loads, the polymer-concrete exhibits a noticeable creep behavior with a linear relation between the creep strains and stresses. After the action of half the ultimate load over 3000 h, the total strains exceed the instantaneous ones by 2.0 to 2.2 times. The accumulation of irreversible strains is also observed; however, their contribution to the total strain is small. It is found that the stress-strain relation can be represented by the equation of linear hereditary creep theory.Institute of Polymer Mechanics, University of Latvia, Riga, LV-1006, Latvia. Translated from Mekhanika Kompozitnykh Materialov, Vol. 35, No. 2, pp. 147–162, March–April, 1999.