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Cytophotometry of rat blood erythroid cells during anaemia, induced by phenylhydrazin (4-8 days from the beginning of injections), revealed that all forms of bone marrow containing haemoglobin were thrown into the blood. On its peak (4th day), the greatest contribution in blood haemoglobinization (50%) is made by microcytes. From the 5th day and up to the end of the restoration period the important role in this process is played by macrocytes. From the 6th day the role of normocytes increases, whose contribution by 8th day reaches 70% of the whole haemoglobin amount in blood. In contrary to anaemizated birds, whose erythroid cells ripen in blood, in rats all the transformations of erythron during anaemia are accomplished in bone marrow.  相似文献   
3.
On the high-temperature subthreshold slope of thin-film SOI MOSFETs   总被引:1,自引:0,他引:1  
This paper addresses the validity of the classical expression for the subthreshold swing (S) in SOI metal-oxide semiconductor field effect transistors (MOSFETs) at high temperature. Using numerical simulation, it is shown that two effects invalidate the classical expression of S at high temperature. Firstly, the depletion approximation becomes invalid and intrinsic free carriers must be taken into account to determine the effective body capacitance. Secondly, the charge-sheet model for the inversion layer becomes inaccurate due to a lowering of the electric field at the surface and a broadening of the inversion layer thickness in weak inversion. These effects must be taken into account to predict accurately the high-temperature subthreshold characteristics of both partially depleted and fully depleted SOI MOSFETs  相似文献   
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Russian Journal of Non-Ferrous Metals - Viscosity of conventional cryolite-alumina melts NaF–AlF3–CaF2–Al2O3 with a cryolite ratio (xNaF/xAlF3, mol/mol) 2.3 was studied in...  相似文献   
6.
Combustion, Explosion, and Shock Waves - A method of obtaining detonation nanodiamonds from tetryl by means of blasting the latter in a water shell with the explosive/water mass ratio of...  相似文献   
7.
Every car of the Volzhskii Automobile Plant consists of 1.6 (VAZ-2106) to 4.0 (VAZ-2110) kilograms of parts fabricated from powder materials. By the middle of 1996 the range of these parts (weighing from 1.5 to 600 g) consisted of 150 items. They are fabricated from powders based on iron and copper (119 and 31 items, respectively). Almost half of the iron-base powder parts are subjected to various kinds of surface treatment, namely, carburizing, cyaniding, gas nitriding, and steam oxide treatment. The present paper is devoted to the special features of chemical heat treatment (CHT) of parts produced from iron (steel) powder materials.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 10, pp. 18–21, October, 1996.  相似文献   
8.
Conclusions 1. The structure of the metal and the design of the fractured bellows (with the exception of the parameters D, L,a and t, which changed during service) satisfy the requirements of the normalization and technical documents.2. The main reason for failure of the bellows is its long-term service, almost four times higher than the design life.3. Failure is also caused by the presence on the surface of the bellows of technological roughness acting as regions of microcrack nucleations.4. To increase the efficiency of bellows, it is efficient to produce them from pipes/blanks with an electrochemically polished surface.5. The detected HV—running life dependence can be used to evaluate approximately the number of operating cycles of failed bellows and also their permissible service life.6. The design life of the bellows of the 44.5–15–0.18×2 type under this loading system may be increased from 3000 to 5000 cycles.Translated from Fiziko-Khimicheskaya Mekhanika Materialov, Vol. 2, No. 2, pp. 125–127, March–April, 1993.  相似文献   
9.
A study was made of a possibility of using Soviet made membranes "Vladipor" with a pore diameter of 16--17 nm for the purpose of concentration and purification of antigenic extracts from stab cultures of S. typhi obtained by the action of typsin, hydrogen peroxide and detergents. Preparations, complete by antigenic structure, were obtained by ultrafiltration, with a good yield. The maximal rate of ultrafiltration was noted in case of "peroxide" antigenic preparations. The use of diafiltration provided a significant reduction of the ash content in the end products.  相似文献   
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