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1.
SF Zakharov SH Kwok H Sokoloff HT Chang SP Radko A Chrambach 《Canadian Metallurgical Quarterly》1998,19(10):1625-1630
An automated gel electrophoresis apparatus, recently available commercially, allows one to follow the band during electrophoresis in real time, and lends itself therefore to an evaluation of bandwidth as a function of migration time (the dispersion coefficient), resolution and band shape. These determinations assume the constancy of band area with migration time and at various gel concentrations. The purpose of the present study was to verify these assumptions. Representative proteins and sodium dodecyl sulfate (SDS)-proteins, either natively fluorescent or fluorescein carboxylate labeled, were found to exhibit band areas which approach constancy as a function of migration time in both agarose and polyacrylamide gel electrophoresis, provided that (i) the protein concentration under the band was low enough to obviate self-quenching of fluorescence; (ii) the separation of the protein of interest from contaminants had progressed sufficiently during the time at which band areas were measured; (iii) the baseline under the peak was sufficiently well defined. However, band areas decrease with increasing gel concentration. Protein peaks exhibited leading and trailing tails. The ratio of the combined tail area to total area appeared to be near-constant at varying migration times. However, that ratio increases with increasing gel concentration. The tail area does not appear to be an artifact of fluorometric detection since it is reproduced upon fluorimetric analysis of the protein eluted from gel slices after electrophoresis. However, it may be due to photochemical destruction under the conditions of repetitive fluorometric peak detection. 相似文献
2.
Forty-seven children afflicted with acute leukemia were studied at the Tata Memorial Hospital Bombay to record the occurrence of oral manifestations prior to and during chemotherapy. Lymphadenopathy was the most frequent single finding suggestive of leukemia during head and neck examination. Gingival abnormalities, bleeding gums and oral mucosal pallor were the other findings on initial oral examination. Due to immunosuppression caused by the chemotherapy drugs oral mucosal ulcerations, uncontrolled herpes, candidiasis and pseudomoniasis were observed. 相似文献
3.
4.
Dynamics of a single fluxon in an annular Josephson junction is studied in the presence of an externally applied magnetic
field H. Due to the interaction of the fluxon with the radial field component, the fluxon moves in a potential well which
height is proportional to H. Several spectacular features of fluxon dynamics analogous to the motion of a particle in a washboard
potential are clearly observed experimentally. Periodic revolutions of the fluxon in the junction lead to a potential induced
emission of plasma waves. These waves are indicated by a resonance at a certain fluxon velocity which depends on the junction
length. Good agreement between experiment, theoretical model and numerical simulations is found. 相似文献
5.
ID Zakharov AM Magasumov NI Simonova IaL E?del''man IuV Simenido 《Canadian Metallurgical Quarterly》1997,90(12):8-12
The authors present results of social and ecologic study carried out in Ufa. The results describe the course of ecologically important processes and phenomena in correlation with the public subjective understanding. Public health is influenced by hygienic parameters of food and water quality as well as a complex of social, economic and psychologic factors. Weak correlation between those parameters and ambient air pollution necessitates more accurate approach to ecologic mapping of cities and to manipulation with data on lower atmosphere pollution with chemical hazards. 相似文献
6.
Yu. M. Mosin I. A. Zakharov E. O. Lavrova M. A. Voinova 《Refractories and Industrial Ceramics》1992,33(1-2):38-43
Conclusions It is shown that in technically suitable conditions for shaping blanks by centrifugal casting, the deposition of the particles occurs with a streamline schedule, and the coarse fractions are deposited during acceleration of the rotation of the mold. The main factor influencing the density of the finely dispersed blanks is the duration of rotation, and for systems containing coarse filler, centrifugal acceleration. Regulating the dimensions (wall thickness) of the blank is possible by altering the concentration of solid phase in the slip and the degree of filling of the mold with it.Translated from Ogneupory, No. 1, pp. 22–24, January, 1992. 相似文献
7.
Alexey B. Nadykto Fangqun Yu Jason Herb 《International journal of molecular sciences》2008,9(11):2184-2193
Hydration directly affects the mobility, thermodynamic properties, lifetime and nucleation rates of atmospheric ions. In the present study, the role of ammonia on the formation of hydrogen bonded complexes of the common atmospheric hydrogensulfate (HSO4−) ion with water has been investigated using the Density Functional Theory (DFT). Our findings rule out the stabilizing effect of ammonia on the formation of negatively charged cluster hydrates and show clearly that the conventional (classical) treatment of ionic clusters as presumably more stable compared to neutrals may not be applicable to pre-nucleation clusters. These considerations lead us to conclude that not only quantitative but also qualitative assessment of the relative thermodynamic stability of atmospheric clusters requires a quantum-chemical treatment. 相似文献
8.
B. S. Zakharov 《Chemical and Petroleum Engineering》1996,32(2):130-134
9.
A. E. Gorodetskii A. V. Markin V. N. Chernikov A. P. Zakharov T. A. Burtseva I. V. Mazul N. N. Shipkov G. D. Tolstolutskaya V. F. Rybalko 《Atomic Energy》1997,82(6):448-462
Conclusions The conditions have been proposed for performing modeling experiments making it possible to predict the accumulation of hydrogen
isotopes in carbon materials which are in contact with a tokamak plasma acting as a source of particles having a flux density
of between 3×1016 and 3×1019 cm−2·sec−1. By analyzing the reemission fluxes formed in the stopping zone of the particles implanted from the plasma it is suggested
that the action of the plasma as regards the sorption of hydrogen is identical to that of annealing the material in an atmosphere
of hydrogen isotopes at a pressure of 1–103 Pa and a temperature of 1200–1700 K. The quantity of absorbed deuterium in POCO, UAM, RGT-B, and USB increases as the temperature
is lowered and the pressure is raised (1500 K, 0.66 Pa→1200 K, 133 Pa). As regards their sorption of deuterium, POCO, UAM,
and RGT behave similarly. There is a tendency for the sorption capacity of materials doped with boron to be reduced. In a
class of itself is the isotropic material USB, whose sorption capacity is a factor of 10–100 lower than that of undoped graphite.
The introduction into these materials of radiation-induced defects (T=300 K) by means of ion irradiation in the range 0.1–1 dpa results in a continuous rise in the deuterium sorption capacity
by a factor of 10–100 (up to 10−2 atomic fraction). The USB graphite demonstrates record low increments in the sorption capacity. In the fluence range identical
to 1–10 dpa the sorption capacity of carbon materials for hydrogen is almost constant. The process of the sorption of hydrogen
isotopes can be described as the filling of two ensembles of traps, deep traps which are difficult to access and readily accessible
Langmuir traps. In the RGT-B materials containing 0.1% of boron, the traps introduced by irradiation with 300-keV neon ions
vanish on annealing in a vacuum (T=1800 K, t=1 min).
Institute of Physical Chemistry, Russian Academy of Sciences.
SINTEZ Scientific and Technical Center, Scientific-Research Institute of Electrophysical Apparatus.
Graphite Scientific-Research Institute.
National Scientific Center, Kharkov Physicotechnical Institute. Translated from Atomnaya énergiya, Vol. 82, No. 6, pp. 448–464,
June, 1997. 相似文献
10.
A. G. Zakharov 《Solid Fuel Chemistry》2007,41(2):107-113
It was shown that a pore in a solid has a force field that acts on molecules from the surrounding gas phase. The axial and radial distributions of forces were studied. The study showed that forces parallel to the pore axis operate at the entrance to and the exit from the pore. These forces can either impede or facilitate the entering of gas molecules into the inner space. Forces that have the radial direction act in the pore space and can either retain gas molecules on its central axis or increase the density of the gas in the space adjacent to pore walls. The influence of these forces alter the velocity distribution of gas filtration in the pore, thus leading to the situation that gas transport is realized along the walls under certain conditions. Equipotential field lines were obtained whose general view gives a clear illustration of the distribution of the field in the pore and in the adjacent environment. 相似文献