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21.
Damien Sulla-Menashe Mark A. Friedl Olga N. Krankina Alessandro Baccini Curtis E. Woodcock Adam Sibley Guoqing Sun Viacheslav Kharuk Vladimir Elsakov 《Remote sensing of environment》2011,115(2):392-403
The Northern Eurasian land mass encompasses a diverse array of land cover types including tundra, boreal forest, wetlands, semi-arid steppe, and agricultural land use. Despite the well-established importance of Northern Eurasia in the global carbon and climate system, the distribution and properties of land cover in this region are not well characterized. To address this knowledge and data gap, a hierarchical mapping approach was developed that encompasses the study area for the Northern Eurasia Earth System Partnership Initiative (NEESPI). The Northern Eurasia Land Cover (NELC) database developed in this study follows the FAO-Land Cover Classification System and provides nested groupings of land cover characteristics, with separate layers for land use, wetlands, and tundra. The database implementation is substantially different from other large-scale land cover datasets that provide maps based on a single set of discrete classes. By providing a database consisting of nested maps and complementary layers, the NELC database provides a flexible framework that allows users to tailor maps to suit their needs. The methods used to create the database combine empirically derived climate–vegetation relationships with results from supervised classifications based on Moderate Resolution Imaging Spectroradiometer (MODIS) data. The hierarchical approach provides an effective framework for integrating climate–vegetation relationships with remote sensing-based classifications, and also allows sources of error to be characterized and attributed to specific levels in the hierarchy. The cross-validated accuracy was 73% for the land cover map and 73% and 91% for the agriculture and wetland classifications, respectively. These results support the use of hierarchical classification and climate–vegetation relationships for mapping land cover at continental scales. 相似文献
22.
Kiselev NA Kumskov AS Zakalyukin RM Vasiliev AL Chernisheva MV Eliseev AA Krestinin AV Freitag B Hutchison JL 《Journal of microscopy》2012,246(3):309-321
Nanocomposites consisting of one-dimensional (1D) crystals of the cationic conductors CuI, CuBr and AgBr inside single-walled carbon nanotubes, mainly (n, 0), were obtained using the capillary technique. 1D crystal structure models were proposed based on the high resolution transmission electron microscopy performed on a FEI Titan 80-300 at 80 kV with aberration correction. According to the models and image simulations there are two modifications of 1D crystal: hexagonal close-packed bromine (iodine) anion sublattice (growth direction <001>) and 1D crystal cubic structure (growth direction <112>) compressed transversely to the nanotube (D(m) ~1.33 nm) axis. Tentatively this kind of 1D crystal can be considered as monoclinic. One modification of the anion sublattice reversibly transforms into the other inside the nanotube, probably initiated by electron beam heating. As demonstrated by micrographs, copper or silver cations can occupy octahedral positions or are statistically distributed across two tetrahedral positions. A 1DAgBr@SWNT (18, 0; 19, 0) pseudoperiodic 'lattice distortion' is revealed resulting from convolution of the nanotube wall function image with 1D cubic crystal function image. 相似文献
23.
M. G. Kiselev D. A. Stepanenko 《Journal of Engineering Physics and Thermophysics》2006,79(6):1202-1207
A mathematical model for estimating the thickness of a coating deposited on the surface of a rotating body having a circular
symmetry is proposed. A method has been developed for determining the law of control of the mass flow of a deposited material
for the purpose of obtaining coatings homogeneous in thickness. It is shown that, in the case of deposition of a coating on
the surface of a circular disk, the optimum mass flow of a deposited material is defined by a linear function.
__________
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 79, No. 6, pp. 149–154, November–December, 2006. 相似文献
24.
I. M. Abdulagatov N. G. Polikhronidi A. Abdurashidova S. B. Kiselev J. F. Ely 《International Journal of Thermophysics》2005,26(5):1327-1368
The isochoric heat capacity of pure methanol in the temperature range from 482 to 533 K, at near-critical densities between
274.87 and 331.59 kg· m−3, has been measured by using a high-temperature and high-pressure nearly constant volume adiabatic calorimeter. The measurements
were performed in the single- and two-phase regions including along the coexistence curve. Uncertainties of the isochoric
heat capacity measurements are estimated to be within 2%. The single- and two-phase isochoric heat capacities, temperatures,
and densities at saturation were extracted from experimental data for each measured isochore. The critical temperature (Tc = 512.78±0.02K) and the critical density (ρc = 277.49±2 kg · m−3) for pure methanol were derived from the isochoric heat-capacity measurements by using the well-established method of quasi-static
thermograms. The results of the CVVT measurements together with recent new experimental PVT data for pure methanol were used to develop a thermodynamically self-consistent Helmholtz free-energy parametric crossover
model, CREOS97-04. The accuracy of the crossover model was confirmed by a comprehensive comparison with available experimental
data for pure methanol and values calculated with various multiparameter equations of state and correlations. In the critical
and supercritical regions at 0.98Tc≤ T ≤ 1.5Tc and in the density range 0.35ρc ≤ ρ leq 1.65 ρc, CREOS97-04 represents all available experimental thermodynamic data for pure methanol to within their experimental uncertainties. 相似文献
25.
Kovalchuk BM Kharlov AV Kiselev VN Kumpyak EV Zorin VB Chupin VV Morozov AV 《The Review of scientific instruments》2007,78(3):033501
The GIT-32 current generator was developed for experiments with current carrying pulsed plasma. The main parts of the generator are capacitor bank, multichannel multigap spark switches, low inductive current driving lines, and central load part. The generator consists of four identical sections, connected in parallel to one load. The capacitor bank is assembled from 32 IEK-100-0.17 (0.17 microF, 40 nH, 100 kV) capacitors, connected in parallel. It stores approximately 18 kJ at 80 kV charging voltage. Each two capacitors are commuted to a load by a multigap spark switch with eight parallel channels. Switches operate in ambient air at atmospheric pressure. The GIT-32 generator was tested with 10, 15, and 20 nH inductive loads. At 10 nH load and 80 kV of charging voltage it provides 1 MA of current amplitude and 490 ns rise time with 0.8 Omega damping resistors in discharge circuit of each capacitor and 1.34 MA530 ns without resistors. The net generator inductance without a load was optimized to be as low as 12 nH, which results in extremely low self-impedance of the generator ( approximately 0.05 Omega). It ensures effective energy coupling with low impedance loads like Z pinch. The generator operates reliably without any adjustments in 40-80 kV range of charging voltage. Maximum jitter (relative to a triggering pulse) at 40 kV charging voltage is about 7 ns and lower at higher charging voltages. Operation and handling are very simple, because no oil and no purified gases are required for the generator. The GIT-32 generator has dimensions of 3200 x 3200 x 400 mm(3) and total weight of about 2500 kg, thus manifesting itself as a simple, robust, and cost effective apparatus. 相似文献
26.
Study of the impact of a new hurdle technology composed of electro‐activated solution and low heat treatment on the canned pea and corn quality and microbial safety 下载免费PDF全文
Viacheslav Liato Steve Labrie Marzouk Benali Mohammed Aïder 《International Journal of Food Science & Technology》2016,51(1):180-193
The objective of this work was to evaluate the quality of sterilised canned pea and corn in electro‐activated brine solutions at moderate temperatures. The lowest change in vitamin C was associated with the lowest heat treatment, while the short treatment time resulted in significant changes in texture and colour of vegetables. Best texture profile was obtained with the acid electro‐activated brine solution for pea and corn. The neutral electro‐activated brine solution resulted in a less firm texture for pea and corn. The green colour and brightness of canned pea were higher when neutral solution was used (a* = ?8.4 ± 0.3) than for the acidic one (a* = ?3.7 ± 0.6). The yellowness of corn was better with the neutral electro‐activated brine solution (b* = 36.32 ± 1.24) than with the acidic one (b* = 28.44 ± 2.39). Thirty‐three percent decrease of energy consumption was obtained using the electro‐activation technology. 相似文献
27.
V. N. Gorobei Yu. A. Kiselev O. S. Vitkovskii M. Yu. Leontiev 《Measurement Techniques》2012,54(11):1213-1218
The primary standard for the unit of pressure, the pascal, its constituent parts, ranges of application, and the results of
key comparisons are described. 相似文献
28.
High-purity single-crystal W and W??Nb?? have been prepared using chemical vapor transport. The impurity composition of the materials has been determined using spark source mass spectrometry and high-temperature vacuum extraction. The radial Nb profile in the alloy has been investigated by electron microscopy. 相似文献
29.
The Am volatility from 4 M NaOH solutions in the course of their ozonation at 80°C was studied. The formation of volatile Am compounds under these conditions was proved by α-ray spectrometry. The whole set of data on the volatility and kinetics of reduction of ozonized Am solutions suggest possible formation of short-lived hydroxo complexes of Am in higher oxidation state, including Am(VIII), along with Am(VI) hydroxo complexes, with AmO4 possibly existing in equilibrium with these Am(VIII) species. No Cm volatility was detected under the same conditions. The observed differences in the behavior of Pu and Am, on the one hand, and Np and Cm, on the other hand, under identical ozonation conditions are attributed to the ability of Pu and Am to be oxidized under these conditions to unstable octavalent state, responsible for their volatility. 相似文献
30.