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931.
932.
The influence of a conductive liquid on the characteristics of shear-horizontal acoustic waves of zeroth order (SH0 mode) propagating in thin piezoelectric plates of lithium tantalate, lithium niobate, and potassium niobate was investigated. Experimental results obtained for SH0 mode devices fabricated on lithium niobate plates are found to be in good agreement with theory. The data presented in this paper is useful for a proper design of various acoustic wave sensors operating in contact with conductive liquids.  相似文献   
933.
The influence of a thin conducting layer and a conducting electrode on the characteristics of acoustic waves propagating in thin plates of potassium niobate is investigated theoretically. The variations in velocity and attenuation as high as 50% and 30 dB per wavelength, respectively, can be achieved for a change in conductance of the thin film layer from 10(-7) to 10(-5) S.  相似文献   
934.
Stress is an inevitable part of life. An organism is exposed to multiple stresses and overcomes their negative consequences throughout its entire existence. A correlation was established between life expectancy and resistance to stress, suggesting a relationship between aging and the ability to respond to external adverse effects as well as quickly restore the normal regulation of biological processes. To combat stress, cells developed multiple pro-survival mechanisms, one of them is the assembly of special stress-induced membraneless organelles (MLOs). MLOs are formations that do not possess a lipid membrane but rather form as a result of the “liquid–liquid” phase separation (LLPS) of biopolymers. Stress-responsive MLOs were found in eukaryotes and prokaryotes, they form as a reaction to the acute environmental conditions and are dismantled after its termination. These compartments function to prevent damage to the genetic and protein material of the cell during stress. In this review, we discuss the characteristics of stress-induced MLO-like structures in eukaryotic and prokaryotic cells.  相似文献   
935.
Based on the generalization of experimental data, we propose a formula for the calculation of the effect of the temperature factor and the transition from a laminar flow regime to one that is turbulent in the boundary layer of a plate; this formula has been confirmed by experiments performed in the following range of parameter variation: 0.5 2.6; 0.2 M 3.6; 0.1 9%.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 16, No. 2, pp.218–224, February, 1969.  相似文献   
936.
Glass Physics and Chemistry - The structural (volume porosity, specific surface area, and average pore radius) and electrokinetic characteristics are studied for silicate and AgI-doped microporous...  相似文献   
937.
938.
939.
The T-x phase diagram along the PbTe-VTe2 join of the Pb-V-Te system has been studied. Vanadium-doped lead telluride crystals have been grown, and the longitudinal vanadium and carrier profiles in the crystals have been investigated. The temperature dependences of resistivity for the crystals lend support to the conclusion drawn earlier that PbTe〈V〉 is in a semi-insulating state at low temperatures. The crystals offer a high 20-K electron mobility, on the order of 105 cm2/(V s), which attests to high electrical homogeneity of the material and stabilization of the Fermi level.  相似文献   
940.
This paper is devoted to detailed theoretical investigation of energy density and power flow of homogeneous (bulk) and inhomogeneous (surface and plate) plane acoustic waves in piezoelectric materials and structures. The analysis of these waves in different materials of various crystallographic orientations allowed us to establish some energy regularities. These regularities are the same for instantaneous energy characteristics of homogeneous waves and for time-average energy characteristics on unit of aperture of inhomogeneous waves if the electrical energy and power flow in vacuum are taken into account. It has been shown that, for strong piezoactive waves, the electric energy density may exceed the mechanical energy density more than three times.  相似文献   
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