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1.
Breakdown of a company is examined and the concept of its stability is given. A system of indexes for characterizing the market position of an enterprise in the chemical industry and predicting its dynamics is proposed. An integral index can be an effective tool in the hands of managers in making managerial decisions related to effectively reacting to changes in the company's market position. 相似文献
2.
Synthesis of 2-[18F]fluoro-2-deoxy-D-glucose ([18F]FDG) involving base hydrolysis was optimized. Fluorine-18 was isolated from irradiated water to more than 90% by sorption of [1
8F]fluoride on QMA anion-exchange resin, which was followed by elution with a 96 : 4 (by volume) acetonitrile-water mixture containing Kryptofix 2.2.2 and potassium carbonate (molar ratio 2 : 1). This composition is the best for preparing the complex [K/K2.2.2]+
18F- used in nucleophilic fluorinations. No additional azeotropic drying is required. Base hydrolysis under optimized conditions (40-45°C), followed by neutralization with HCl, removal of traces of the solvent, and purification of the final product on a combined SCX/Alumina N column, yielded [1
8F]FDG of high radiochemical (>99%) and chemical purity with minimal product loss. With an RB-86 robotic system (Anatech, Sweden), the synthesis time was 38 min. The procedure is used in the Institute of Human Brain, Russian Academy of Sciences for routine synthesis of FDG; the radiochemical yield of the product by the end of synthesis (EOS) is reproducibly high: 63±3% (n = 40). 相似文献
3.
A. M. Kozodaev O. V. Shvedov V. N. Konev B. Yu. Sharkov V. V. Vasil'ev E. B. Volkov N. V. Lazarev A. M. Raskopin G. G. Shimchuk P. V. Bogdanov A. I. Kiryushin V. V. Petrunin E. I. Azhnin E. I. Tyurin I. I. Titaev Yu. P. Severgin A. Yu. Konstantinov 《Atomic Energy》2003,94(1):56-60
The purpose and current construction status, at the Institute of Theoretical and Experimental Physics, of an experimental electronuclear setup, combining a pulsed proton linear accelerator (36 MeV, 0.5 mA) and a subcritical blanket thermal-power assembly 100 kW, are discussed. The main equipment is already available or is being built in industry. The setup can be used to investigate the dynamics of the interaction of a linac–driver and a subcritical reactor and problems concerning the accelerator–driver and the target–blanket assembly. The proton beams and neutron fluxes will be used for applied purposes. In the future it will be possible to increase substantially the current and energy of the proton beam. 相似文献
4.
V. P. Vasil'ev 《Inorganic Materials》2004,40(5):445-450
New thermodynamic data for the In–Sb system are obtained and compared with calculation results available in the literature. An isothermal vacuum cell and a procedure for electrolyte preparation are described which ensure high measurement accuracy. 相似文献
5.
BE Volos IuM Vasil'ev LV Masliaeva IA Snegurskaia 《Canadian Metallurgical Quarterly》1994,(3-4):92-95
Studied in the course of one-stage epidemiologic survey of 1191 individuals were the threshold of gustatory sensitivity to table salt and nycterine natriuresis, relation of these indices to dietary habits, some risk factors for cardiovascular disorders and clinical parameters. Differing relations were established between gustatory sensitivity to table salt and natriuresis and age and gender of the examinees, the level of blood pressure, aggravated heredity in respect of arterial hypertension, smoking and alcohol abuse, this enabling one to embark upon a differential approach to dietetic correction of salt consumption. 相似文献
6.
I. Zh. Bus'ko V. V. Golubkov M. I. Vasil'ev V. V. Pshenitsina V. A. Tsekhomskii 《Glass Physics and Chemistry》2002,28(3):124-134
The halide phase in copper halide photochromic glasses is studied by the small-angle X-ray scattering (SAXS) technique. The dependences of the volume and composition of the halide phase on the temperature of primary heat treatment are determined. The temperature of the formation of a vacuum pore upon cooling from the temperature of primary heat treatment and the temperature of pore disappearance upon heating are investigated as functions of the size of the halide phase regions. The influence of the size of the halide phase regions and the temperature of secondary heat treatment on the crystallization temperature of the halide phase is elucidated. It is shown that the previously observed increase in the crystallization temperature of the halide phase with an increase in the size of the phase regions is associated with the change-over from homogeneous to heterogeneous crystallization. In turn, the mechanism of crystallization depends on the region where the vacuum pore is formed. In the case when the effective radii of drops are less than 130–140 Å, the vacuum pore is formed in the bulk of a liquid drop and the homogeneous crystallization occurs. The nuclei of heterogeneous crystallization arise when the formation of the vacuum pore is accompanied by the destruction of the vitreous matrix. This takes place when the radii of liquid drops are larger than 165–170 Å. The nuclei of heterogeneous crystallization disappear upon heat treatment of glasses at temperatures above 600°C. As a result, upon cooling from these temperatures, the homogeneous crystallization is observed in all cases and the crystallization temperature does not depend on the size of the halide phase regions. 相似文献
7.
V. A. Sychevskii N. V. Pavlyukevich L. L. Vasil'ev S. Rozin 《Journal of Engineering Physics and Thermophysics》2003,76(1):18-27
A problem of the Stefan type which describes heat and mass transfer in a porous body with the double phase transition liquid–ice–vapor has been formulated and solved. 相似文献
8.
A. M. Vasil'ev 《Chemical and Petroleum Engineering》1992,28(7):409-410
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 7, pp. 1–2, July, 1992. 相似文献
9.
N S Sergeeva M Iu Vasil'ev T I Kovalenko N V Sokolova G I Avdeev 《Eksperimental?nai?a onkologii?a》1989,11(2):35-37
The indirect immunofluorescent technique was used to study the distribution of the ascitic fluid antigen (AgD) on histological sections from surgical specimens of gastric and colon tumours from proximal to distal lines of resection. AgD was found in gastric tumours exceptionally in the tumour area and in colon cancer--both in the tumour stroma and in surrounding histologically normal mucosa. 相似文献
10.
The layer reexcavation ratio is proposed to use for determination of overburden thickness in the combined conveying and direct-dumping systems of mining by draglines with haulage to goaf. It is established that this method ensures the decrease in costs of mining the horizontal and flat-dipping deposits. 相似文献