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1.
A new protein composition from defibrinated blood and lactic acid paste, prepared from skim milk, has been recommended as a food product. Optimization of protein composition was conducted on the basis of amino acid components and the criterion of "minimal dispersity".  相似文献   
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Under study was the efficacy of three schedules of dose fractionation in intracavitary gamma-therapy in cervical cancer patients treated on the machine "AGAT-B". Single doses were 1000, 700 and 500 rad, while total dosage at point A depending on the stage of the disease was within the range of 4000-5000 rad. The survival during the first, second and third years following termination of the radiotherapy was found to be identical for patients of all the groups under examination. No differences were noted in them also in the character of early radiation reactions on the part of the adjacent organs. The frequency and severity of late radiation injuries of the urinary bladder, rectum and vagina were related to the dose fractionation regimen.  相似文献   
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Presented here is a brief review of research of an authors’ collective dealing with laser treatment of materials, sintering metallic powders, and multiscale simulation. A theoretical analysis of the processes of structure formation upon the rapid laser synthesis of composite coatings has been performed. The experimentally obtained structural and phase characteristics of the sintered layers have been explained based on an analytical and numerical simulation of the dynamics of thermal fields in the zone of treatment, processes of melting, and subsequent solidification of porous materials. Upon rapid sintering and solidification, the effect of impurity trapping has been taken into account, which determines the chemical composition of the powders under nonequilibrium conditions of their formation. It has been shown that rapid laser treatment retains the composite structure of the powder layer due to the high rates of local heating/cooling and high rate of solidification comparable with the rate of diffusion of chemical components. The results obtained are applicable in the development of a wide class of functional-gradient composite materials.  相似文献   
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Emission spectra and the intensity patterns of InAsSbP/InAsSb/InAsSbP-based diode lasers with different cavity lengths and a spectral range of 3–4 μm were studied. It is ascertained experimentally that a 200-to 300-μm-long and 18-μm-wide laser cavity ensures single-mode lasing, during which the wavelengthdecreases with current by about 100 ? and the top of the intensity pattern becomes bimodal, thus indicating that there are transverse spatial oscillations of laser flux in the cavity. In a 300-to 500-μm-long cavity, several tens of modes are generated mainly on the long-wavelength side of the mode that prevailed initially at the lasing threshold and spatial oscillations of laser flux are not observed. Single-mode lasing is attained due to the fact that the transverse oscillations of laser flux flatten the dynamic dielectric phase grating, which is usually produced by the interaction between lasing modes, and prevent an increase in amplification on the long-wavelength side of the dominant mode. __________ Translated from Fizika i Tekhnika Poluprovodnikov, Vol. 36, No. 11, 2002, pp. 1388–1392. Original Russian Text Copyright ? 2002 by Astakhova, Danilova, Imenkov, Kolchanova, Yakovlev.  相似文献   
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The average irradiation dose to the thyroid gland is estimated for the people living in 4105 populated points in the Bryanskaya, Tul'skaya, Orlovskaya, and Kaluzhskaya oblasts. The basic principles of the method used to reconstruct the dose are presented. The people living in Bryanskaya oblast have the highest irradiation dose to the thyroid gland: in children less than 3 yr old the individual dose reached 10 Gy; the average dose exceeded 2.5 Gy in 12 populated points. In children living in Bryanskaya oblast, for populated points with soil contamination density above 37 kBq/m2 the irradiation dose exceeded 0.05 Gy. The highest average irradiation dose to the thyroid gland in children living in Tul'skaya, Orlovskaya, and Kaluzhskaya oblasts is 0.3–1 Gy. The collective irradiation dose for the four most strongly contaminated oblasts is estimated to be as follows: Bryanskaya – 60, Tul'skaya – 20, Orlovskaya – 13, Kaluzhskaya – 3.5 thousand·people·Gy.  相似文献   
8.
An analysis is made and generalized data presented on the true volumetric vapor content of boiling two-phase flows of Freon-12.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 48, No. 2, pp. 190–193, February, 1985.  相似文献   
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Radioiodine long has proven to be a safe and effective treatment for thyroid disease. Nonetheless, persisting concerns regarding radiogenic stochastic risks (e.g., carcinogenesis) to patients, their families, and the general public have led regulators to establish criteria for release of 131I-containing patients from medical confinement, with limits ranging from as low as 2 mCi in some parts of Europe to as high as 30 mCi in the United States. To optimize clinical efficacy and cost-effectiveness of 131I therapy, such regulations should be based on logical dosimetric considerations. The thyroidal absorbed dose, proportional to maximum uptake and effective half-life and inversely proportional to mass, is typically approximately 1,500 rad/mCi of 131I administered to a euthyroid adult (based on a thyroid maximum uptake of 25%, effective half-life equivalent to the physical half-life of 131I (8.04 days), and mass of 20 g). As thyroid uptake increases from 0% to 100%, extrathyroidal absorbed doses range from a minimum of 0.15 to 0.5 rad/mCi for breast and gonads to a maximum of 1.5 to 2 rad/mCi for stomach and salivary glands; the absorbed doses of the urinary bladder wall, in contrast, decrease with increasing thyroid uptake, from 2 to 0.6 rad/mCi. In hyperthyroid patients (approximately 15%) with a small iodine pool (so-called small patients), the short effective half-life of radioiodine in the thyroid and high serum concentrations of long-lived protein-bound 131I result in a standard 7,000-rad absorbed dose for treatment of Graves' disease requiring an administered activity of 28 mCi of 131I and yielding a prohibitively high blood absorbed dose of 150 rad. Importantly, once the fetal thyroid begins to function and accumulate radioiodine at a gestational age of 10-12 weeks, fetal thyroid absorbed doses as large as 5,000 rad/mCi of 131I administered to the mother can result. Thus, pregnancy is an absolute contraindication to administration of 131I because of the risk of radiogenic cretinism. Based on actual measurements of thyroid activity and of external absorbed dose, the total thyroid and mean extrathyroidal absorbed doses to adult family members from immediately released 131I-treated patients are approximately 0.01 and approximately 0.02 rad/mCi administered, respectively, yielding an effective dose of approximately 0.02 rem/mCi. A maximum permissible effective dose of 0.5 rem for adults therefore is consistent with a release criterion of 30 mCi of retained 131I. Lower-activity release criteria therefore may be unnecessarily restrictive.  相似文献   
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