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151.
Both lath-shaped and martensites are induced by tensile deformation within of a two-phase ( + ) Fe-Cr-Ni stainless steel, forms from the through the at an intersection of two crystals. These are observed both when is surrounded by and when borders . The amount of strain at which both and nucleate, increases with test temperatures in the range –196 to 50° C. Adjacent laths are either twin-related, or 5, 9, 15 or 19° off the twin relationship, as found by analysing electron diffraction patterns. 相似文献
152.
Satoru Maegawa Takao Mizusaki Yutaka Hirayoshi Tadashi Kusumoto Akira Hirai 《Journal of Low Temperature Physics》1980,39(1-2):151-171
Nuclear spin-lattice relaxation properties of hcp solid 3He with 4He impurities have been studied. At temperatures below the exchange plateau region, three kinds of relaxation time were observed. To analyze the data, a phenomenological four-bath model was developed, the four baths being the Zeeman bath, the phonon bath, an X-bath, and a Y-bath. The X-bath consists of the exchange bath and a part of the 4He-4He elastic interaction bath. The Y-bath is the main part of the elastic interaction bath. We measured the concentration dependence of the energy constants of all the baths, as well as the temperature and concentration dependences of the three kinds of relaxation time. The relaxation behavior corresponding to the process between the X-bath and the Y-bath could not be expressed by a single exponential function of time and the relaxation rate was strongly dependent on the concentration. This process may be related to the internal thermal equilibrium process within the elastic interaction bath. The impurity-dependent relaxation time between the X-bath and the phonon bath had a temperature dependence of T
–n with n = 7.4±0.3. 相似文献
153.
154.
Many sorting algorithms have been studied in the past, but there are only a few algorithms that can effectively exploit both single‐instruction multiple‐data (SIMD) instructions and thread‐level parallelism. In this paper, we propose a new high‐performance sorting algorithm, called aligned‐access sort (AA‐sort), that exploits both the SIMD instructions and thread‐level parallelism available on today's multicore processors. Our algorithm consists of two phases, an in‐core sorting phase and an out‐of‐core merging phase. The in‐core sorting phase uses our new sorting algorithm that extends combsort to exploit SIMD instructions. The out‐of‐core algorithm is based on mergesort with our novel vectorized merging algorithm. Both phases can take advantage of SIMD instructions. The key to high performance is eliminating unaligned memory accesses that would reduce the effectiveness of SIMD instructions in both phases. We implemented and evaluated the AA‐sort on PowerPC 970MP and Cell Broadband Engine platforms. In summary, a sequential version of the AA‐sort using SIMD instructions outperformed IBM's optimized sequential sorting library by 1.8 times and bitonic mergesort using SIMD instructions by 3.3 times on PowerPC 970MP when sorting 32 million random 32‐bit integers. Also, a parallel version of AA‐sort demonstrated better scalability with increasing numbers of cores than a parallel version of bitonic mergesort on both platforms. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
155.
This study introduces the emerging integrated ecosystem management approach known as Payments for Watershed Services (PWS) as utilized for lake and reservoir basin governance. PWS is built on the central concept of providing economic incentives to watershed stakeholders to assist in management efforts. It channels conservation payments from downstream payers to finance conservation activities conducted by upstream payees. The upstream conservation activities are expected to enhance ecosystem functions, thereby improving water‐related ecosystem services desired by downstream stakeholders. Information on 163 PWS projects in 34 developing countries through the year 2008 was collected and analysed, including their common goals, processes, outcomes, scientific assumptions and socioeconomic rationales. This study recognized one unique PWS characteristic, namely the role of intermediary organizations (i.e. brokers) in integrating the economic incentives of upstream payees and downstream payers in order to facilitate their transactions by means of contracts. Although 75% of the reviewed PWS projects have focused on rivers, and only 10% have considered lakes and reservoirs, the similarity of the intermediary functions performed by lake management organizations and PWS intermediary organizations suggests a greater potential for the future application of PWS designs in lake basins. Drawing on components in the field of New Institutional Economics to interpret the intermediary function within the PWS framework, a three‐part PWS design with 15 steps is proposed in this study for lake basin governance, with a Costa Rican PWS scheme serving as an illustration. This study seeks to communicate the scientific and socioeconomic frontiers for developing locally suitable and integrated watershed governance structures to lake management organizations and other watershed stakeholder groups. 相似文献
156.
M Kusunoki K Kimura M Nakamura Y Isaka S Yoneda H Abe 《Canadian Metallurgical Quarterly》1981,1(4):413-417
The contribution of hematocrit (Ht) changes on cerebral blood flow (CBF) and brain oxygenation in ischemic cerebrovascular disease is still controversial. In the present study, effects of Ht variations of CBF and oxygen delivery were investigated in patients with ischemic cerebrovascular disease. CBF was measured by the Xe-133 intracarotid injection method in 27 patients, whose diagnoses included completed stroke, reversible ischemic neurological deficit, and transient ischemic attack. Ht values in the patients ranged from 31 to 53%. There was a significant inverse correlation between CBF and Ht in these Ht ranges. Oxygen delivery, i.e., the product of arterial oxygen content and CBF, increased with Ht elevation and reached the maximum level in the Ht range of 40-45% and then declined. The CBF-Ht and oxygen transport-Ht relations observed in our study were similar to those in the glass-tube model studies by other workers rather than to those in intact animal experiments. From these results, it is conceivable that in ischemic cerebrovascular disease, the vasomotor adjustment was impaired in such a manner that the relations among Ht, CBF, and oxygen delivery were different from those in healthy subjects. Further, an "optimal hematocrit" for brain oxygenation was also discussed. 相似文献
157.
The size distribution of gold nanoparticles was estimated based on the scattering intensity data obtained from small angle X-ray scattering (SAXS) and compared with the result of micrographs by transmission electron microscopy. The slope of the Guinier plot was used to estimate the mean size assuming a narrow particle size distribution. When the size distribution is narrow, the mean size can be easily obtained from slope of a Guinier plot of scattering data within 10% error. Additionally, assuming a lognormal size distribution, the size distribution and the mean size can be calculated using the experimental SAXS data in the fitting analysis. The histogram method, which utilizes the coefficient matrix of scattering intensity, was also applied to the estimation of the size distribution, and this method could be useful for a rough estimate of the size distribution. 相似文献
158.
In this paper the stress intensity factors are discussed for an inclined elliptical crack near a bimaterial interface. The solution utilizes the body force method and requires Green’s functions for perfectly bonded semi-infinite bodies. The formulation leads to a system of hypersingular integral equation whose unknowns are three modes of crack opening displacements. In the numerical calculation, unknown body force densities are approximated by using fundamental density functions and polynomials. The results show that the present method yields smooth variations of stress intensity factors along the crack front accurately. Distributions of stress intensity factors are presented in tables and figures with varying the shape of crack, distance from the interface, and elastic modulus ratio. It is found that the inclined crack can be evaluated by the models of vertical and parallel cracks within the error of 24% even for the cracks very close to the interface. 相似文献
159.
Etching characteristics of high-k dielectric materials (HfO2) and metal electrode materials (Pt, TaN) have been studied in high-density chlorine-containing plasmas at pressures around 10 mTorr. The etching of HfO2 was performed in BCl3 without rf biasing, giving an etch rate of about 5 nm/min with a high selectivity of >10 over Si and SiO2. The etching of Pt and TaN was performed in Ar/O2 with high rf biasing and in Ar/Cl2 with low rf biasing, respectively, giving a Pt etch rate of about several tens nm/min and a TaN etch rate of about 200 nm/min with a high selectivity of >8 over HfO2 and SiO2. The etched profiles were outwardly tapered for Pt, owing to the redeposition of etch or sputter products on feature sidewalls, while the TaN profiles were almost anisotropic, probably owing to the ion-enhanced etching that occurred. 相似文献
160.
A break of wiring by stress-migration becomes a problem with an integrated circuit such as LSI. The present study investigates residual stress in SiO2/Cu/TiN film deposited on glass substrates. A TiN layer, as an undercoat, was first deposited on the substrate by arc ion plating and then Cu and SiO2 layers were deposited by plasma coating. The crystal structure and the residual stress in the deposited multi-layer film were investigated using in-lab. X-ray equipment and a synchrotron radiation device that emits ultra-high-intensity X-rays. It was found that the SiO2 film was amorphous and both the Cu and TiN films had a strong {1 1 1} orientation. The Cu and TiN layers in the multi thick (Cu and TiN:1.0 μm)-layer film and multi thin (0.1 μm)-layer film exhibited tensile residual stresses. Both tensile residual stresses in the multi thin-layer film are larger than the multi thick-layer film. After annealing at 400 °C, these tensile residual stresses in both the films increased with increasing the annealing temperature. Surface swelling formations, such as bubbles were observed in the multi thick-layer film. However, in the case of the multi thin-layer films, there was no change in the surface morphology following heat-treatment. 相似文献