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61.
Using sea surface temperature (SST) and wind speed retrieved by the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI), for the period of 1998–2003, we have studied the annual cycle of SST and confirmed the bimodal distribution of SST over the north Indian Ocean. Detailed analysis of SST revealed that the summer monsoon cooling (winter cooling) over the eastern Arabian Sea (Bay of Bengal) is more prominent than winter cooling (summer monsoon cooling). A sudden drop in surface short wave radiation by 57 W m?2 (74 W m?2) and rise in kinetic energy per unit mass by 24 J kg?1 (26 J kg?1) over the eastern Arabian Sea (Bay of Bengal) is observed in summer monsoon cooling period. The subsurface profiles of temperature and density for the spring warming and summer monsoon cooling phases are studied using the Arabian Sea Monsoon Experiment (ARMEX) data. These data indicate a shallow mixed layer during the spring warming and a deeper mixed layer during the summer monsoon cooling. Deepening of the mixed layer by 30 to 40 m with corresponding cooling of 2°C is found from warming to summer monsoon cooling in the eastern Arabian Sea. The depth of the 28°C isotherm in the eastern Arabian Sea during the spring warming is 80 m and during summer monsoon cooling it is about 60 m, while over the Bay of Bengal the 28°C isotherm is very shallow (35 m), even during the summer monsoon cooling. The time series of the isothermal layer depth and mixed layer depth during the warming phase revealed that the formation of the barrier layer in the spring warming phase and the absence of such layers during the summer cooling over the Arabian Sea. However, the barrier layer does exist over the Bay of Bengal with significant magnitude (20–25 m). The drop in the heat content with in first 50 m of the ocean from warming to the cooling phase is about 2.15 × 108 J m?2 over the Arabian Sea.  相似文献   
62.
Owing to the rapid development and advancements in the field of networks and communication, sharing of multimedia contents over insecure networks has becom  相似文献   
63.
Multimedia Tools and Applications - Image segmentation is a crucial step in remote sensing application, as it breaks down a larger image into smaller chunks, which contains useful information....  相似文献   
64.
65.
We have studied the feasibility of electron conduction in azulene molecule and compared with that in its isomer naphthalene. We have used non-equilibrium Green’s function formalism to measure the current in our systems as a response of the external electric field. Parallely we have performed the Gaussian calculations with electric field in the same bias window to observe the impact of external bias on the wave functions of the systems. We have found that the conduction of azulene is higher than that of naphthalene inspite of its intrinsic donor-acceptor property, which leads a system to more insulating state. Due to stabilization through charge transfer the azulene system can be fabricated as a very effective molecular wire. Our calculations show the possibility of huge device application of azulene in nano-scale instruments.  相似文献   
66.
Venkatesh  M.  Priya  G. Lakshmi  Balamurugan  N. B. 《SILICON》2021,13(3):911-918
Silicon - In this study, we present an ambipolar conduction and RF stability performance for a Germanium Source Dual Halo Dual Dielectric Triple Material Surrounding Gate Tunnel FET...  相似文献   
67.
The innate and adaptive immune systems play an essential role in host defense against pathogens. Various signal transduction pathways monitor and balance the immune system since an imbalance may promote pathological states such as allergy, inflammation, and cancer. Mast cells have a central role in the regulation of the innate/adaptive immune system and are involved in the pathogenesis of many inflammatory and allergic diseases by releasing inflammatory mediators such as histamines, proteases, chemotactic factors, and cytokines. Although various signaling pathways are associated with mast cell activation, our discovery and characterization of the pLysRS-Ap4A signaling pathway in these cells provided an additional important step towards a full understanding of the intracellular mechanisms involved in mast cell activation. In the present review, we will discuss in depth this signaling pathway’s contribution to host defense and the pathological state.  相似文献   
68.
Atomically precise nanoclusters (NCs) have recently emerged as ideal building blocks for constructing self-assembled multifunctional superstructures. The existing structures are based on various non-covalent interactions of the ligands on the NC surface, resulting in inter-NC interactions. Despite recent demonstrations on light-induced reversible self-assembly, long-range reversible self-assembly based on dynamic covalent chemistry on the NC surface has yet to be investigated. Here, it is shown that Au25 NCs containing thiolated umbelliferone (7-hydroxycoumarin) ligands allow [2+2] photocycloaddition reaction-induced self-assembly into colloidal-level toroids. The toroids upon further irradiation undergo inter-toroidal reaction resulting in macroscopic supertoroidal honey-comb frameworks. Systematic investigation using electron microscopy, atomic force microscopy (AFM), and electron tomography (ET) suggest that the NCs initially form spherical aggregates. The spherical structures further undergo fusion resulting in toroid formation. Finally, the toroids fuse into macroscopic honeycomb frameworks. As a proof-of-concept, a cross-photocycloaddition reaction between coumarin-tethered NCs and an anticancer drug (5-fluorouracil) is demonstrated as a model photo-controlled drug release system. The model system allows systematic loading and unloading of the drug during the assembly and disassembly under two different wavelengths. The results suggest that the dynamic covalent chemistry on the NC surface offers a facile route for hierarchical multifunctional frameworks and photocontrolled drug release.  相似文献   
69.
Recently, C.D. Bei and R.M. Gray (1985) used a partial distance search algorithm that reduces the computational complexity of the minimum distortion encoding for vector quantization. The effect of ordering the codevectors on the computational complexity of the algorithm is studied. It is shown that the computational complexity of this algorithm can be reduced further by ordering the codevectors according to the sizes of their corresponding clusters  相似文献   
70.
The total vapour pressure and the composition of the liquid and vapour phases of the benzene and n-heptane system have been experimentally determined under equilibrium conditions at 110, 125, 140, 155, 170, 185, 200 and 215 °C. The corresponding composition of the vapour phase was also estimated using an expression for the liquid phase activity coefficient as a function of the composition of the liquid phase. Several expressions were compared and it has been found that the three-constant Redlich and Kister equation gave the best fit of the experimental vapour pressure data than the other equations. Comparison between the calculated and measured vapour compositions has shown a discrepancy of ymeas,—ycalc. of the order of 0.02 mol fraction or 10 times the experimental tolerance. Nevertheless, the experimental values were reasonably thermodynamically consistent. The low values of the liquid phase activity coefficients indicated that the behaviour of this particular system was not far from ideality. Also, it was found that the degree of non-ideality decreased with the increase in temperature. The behaviour of the vapour phase was shown also to be nearly ideal. The excess Gibbs free energy of mixing was calculated, and it was found to be non-symmetrical with mole fraction. On increasing the temperature of the system, the liquid composition corresponding to the maximum GE tended to shift to a higher benzene concentration, whilst at a fixed liquid composition, GE initially decreased and then remained stationary or increased again. This was thought to be due to differences in the molar volumes of the two components.  相似文献   
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