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排序方式: 共有518条查询结果,搜索用时 296 毫秒
41.
Shami Abdallah Assi Chadi Habib I. Ali M. A. Ghani N. 《Photonic Network Communications》2003,6(1):25-32
This paper investigates and compares the performance of two GMPLS-based distributed control and management protocols for dynamic lightpath provisioning in future IP networks. The first protocol is a global information-based link state approach that consists of both an integrated RWA algorithm and a signaling algorithm. Two triggering mechanisms for the LSAs update procedures are considered; one is periodic-based and the other is threshold-based. The second protocol is a local-information based fixed alternate link routing approach where the signaling protocol is closely integrated with the RWA protocols. 相似文献
42.
Journal of Materials Science Letters - 相似文献
43.
Dielectric constant (ε′) and tan δ dependence on distance from the outer most skin to the center of bamboo has been determined. Dielectric measurements have been done in the temperature range from 24 to 120°C and in the frequency range from 4 to 100 kHz. Gradient behavior in dielectric constant (ε′) and tan δ has been found in bamboo. It has also been observed that the dielectric constant (ε′) and tan δ increase with the increasing temperature and decrease with the increasing frequency. Relaxation times have been calculated for the four samples at 80, 90, and 100°C temperatures, which show that relaxation time decreases with the increase of temperature due to the increased molecular mobility. A continuous increase in the hardness from the center 48 to the outer surface 70 and density from 0.45 to 0.80 g/cc has been observed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3489–3494, 2006 相似文献
44.
Shin D.S. Wang J. Bosch F. Kiely P.A. Chand N. Fischer M. Kojima K. Kasper B.L. Peral E.M. Ransijn H. 《Electronics letters》2002,38(16):864-865
A 1.3 μm uncooled transmitter with wide-open eye diagrams at laser temperatures of 20, 50, and 85°C is presented. Using this transmitter, it is demonstrated that 10 Gbit/s transmission is possible over a 50 km nonzero dispersion-shifted Lucent TrueWave-RS fibre. This result is compared with transmission over a 55 km standard singlemode fibre 相似文献
45.
Md Shahabuddin A G Vedeshwar H D Bist Prem Chand S K Agarwal A V Narlikar 《Bulletin of Materials Science》1991,14(3):789-792
Low-field differential microwave absorption has been studied for hafnium-doped Y-Ba-Cu-O at the first harmonic of modulation
field. The effect of modulation amplitude on peak height, peak position and the area under hysteresis curve has been discussed. 相似文献
46.
47.
Jagan Singh Meena Simon Min Sze Umesh Chand Tseung-Yuen Tseng 《Nanoscale research letters》2014,9(1):526
Nonvolatile memory technologies in Si-based electronics date back to the 1990s. Ferroelectric field-effect transistor (FeFET) was one of the most promising devices replacing the conventional Flash memory facing physical scaling limitations at those times. A variant of charge storage memory referred to as Flash memory is widely used in consumer electronic products such as cell phones and music players while NAND Flash-based solid-state disks (SSDs) are increasingly displacing hard disk drives as the primary storage device in laptops, desktops, and even data centers. The integration limit of Flash memories is approaching, and many new types of memory to replace conventional Flash memories have been proposed. Emerging memory technologies promise new memories to store more data at less cost than the expensive-to-build silicon chips used by popular consumer gadgets including digital cameras, cell phones and portable music players. They are being investigated and lead to the future as potential alternatives to existing memories in future computing systems. Emerging nonvolatile memory technologies such as magnetic random-access memory (MRAM), spin-transfer torque random-access memory (STT-RAM), ferroelectric random-access memory (FeRAM), phase-change memory (PCM), and resistive random-access memory (RRAM) combine the speed of static random-access memory (SRAM), the density of dynamic random-access memory (DRAM), and the nonvolatility of Flash memory and so become very attractive as another possibility for future memory hierarchies. Many other new classes of emerging memory technologies such as transparent and plastic, three-dimensional (3-D), and quantum dot memory technologies have also gained tremendous popularity in recent years. Subsequently, not an exaggeration to say that computer memory could soon earn the ultimate commercial validation for commercial scale-up and production the cheap plastic knockoff. Therefore, this review is devoted to the rapidly developing new class of memory technologies and scaling of scientific procedures based on an investigation of recent progress in advanced Flash memory devices. 相似文献
48.
Degradation of RC (reinforced concrete) in maritime structures has become a worldwide problem due to its excessive costs of maintenance, repair and replacement in addition to its environmental impacts and safety issues. Degradation of both concrete and steel which is the main reason of reduction in the service life of RC structures strongly depends on the diffusion process of moisture and aggressive species. In this paper, the major and popular mathematical models of diffusion process in concrete are surveyed and investigated. Predominantly in these models, the coefficient of chloride diffusion into the concrete is assumed to be constant. Whereas, experimental records indicate that diffusion coefficient is a function of time. Subsequently, data analysis and comparisons between the existing analytical models for predicting the diffusion coefficient with the existing experimental database are carried out in this study. Clearly, these comparisons reveal that there are gaps between the existing mathematical models and previously recorded experimental results. Perhaps, these gaps may be interpreted as influence of the other affecting parameters on the diffusion coefficient such as temperature, aggregate size and relative humidity in addition to the water cement ratio. Accordingly, the existing mathematical models are not adequate enough to predict the diffusion coefficient precisely and further studies need to be performed. 相似文献
49.
In this paper, novel nanoscale MOSFET with Source/Drain-to-Gate Non-overlapped and high-k spacer structure has been demonstrated to reduce the gate leakage current for the first time. The gate leakage behaviour of novel MOSFET structure has been investigated with help of compact analytical model and Sentaurus Simulation. Fringing gate electric field through the dielectric spacer induces inversion layer in the non-overlap region to act as extended S/D region. It is found that optimal Source/Drain-to-Gate Non-overlapped and high-k spacer structure has reduced the gate leakage current to great extent as compared to those of an overlapped structure. Further, the proposed structure had improved off current, subthreshold slope and DIBL characteristic. It is concluded that this structure solves the problem of high leakage current without introducing the extra series resistance. 相似文献
50.
The sliding wear of isotactic polypropylene (PP), polyethylene terephthalate (PET) and their blends was evaluated as a function
of applied pressure and composition against a stainless steel counter face in dry condition. Wear rate decreases with the
addition of PET in the blend. The wear was observed in two stages, the moderate wear and high wear while increasing the applied
pressure on test samples. The addition of PET in PP helps in increasing the limit of moderate wear towards the high-pressure
side. Microstructure and worn surfaces of samples were observed by scanning electron microscope. The wear phenomenon has been
discussed based on wear losses and worn surfaces. 相似文献