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51.
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
52.
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
53.
C Rumi S Rutella L Teofili B Etuk E Ortu La Barbera G Micciulli MT Voso G Leone 《Canadian Metallurgical Quarterly》1997,25(3):246-251
OBJECTIVE: The purpose of this study was to differentiate between the catabolic effects of interleukin-1 (IL-1) when infused into the central nervous system or into the periphery. SUMMARY BACKGROUND DATA: After injury and infection, IL-1 has been found in the central nervous system. Chronic intracerebrovascular infusion of IL-1 produces protein catabolism, anorexia, and fever. However, IL-1 may act directly on liver and bone marrow to elicit metabolic responses. Although IL-1 is thought to be involved in a number of metabolic responses associated with injury-inflammation, the sites of action are unclear. METHODS: Rats were implanted with chronic infusion pumps and received diluent or three doses of IL-1 infused subcutaneously for 6 days, and a variety of response variables were measured. In a second study, doses were adjusted so that similar systemic catabolic responses were obtained from peripheral and intracerebroventricular infusion of IL-1. The acute-phase responses then were compared in the two groups of animals receiving IL-1 by different routes. RESULT: Subcutaneously infused IL-1 elicited catabolic responses in a dose-response manner. Similar catabolic responses were achieved by infusing one tenth of the dose of IL-1 given subcutaneously into the central nervous system. Although similar systemic responses (protein catabolism, anorexia, fever, and weight loss) were observed with both routes of infusion, the subcutaneous infusion produced a much greater lymphocytosis, elevation in acute-phase reactants, and fall in serum iron and albumin. CONCLUSIONS: The IL-1 appears to have different effects depending on the site of production and site of action. Regionalization of signal proteins such as IL-1 should be taken into consideration when devising specific anticytokine treatment strategies. 相似文献
54.
A chain growth model for heterogeneous secondary reactions is developed for the pyrolysis of large wood particles and the parameters determined by nonlinear optimization. The model takes both the volatile retention time and cracking and repolymerization reactions of the vapours with the decomposing solid as well as sutocatalysis into consideration. The extent of the secondary reactions is strongly influenced by the time and the ratio of the autocatalytic (propagation) reaction rate to noncatalytic (initiation) reaction rate. The wood which has a higher value of the autocatalytic/noncatalytic ratio also has a higher exothermic heat of reaction and yields a higher amount of final char residue. This fact confirms the heterogeneous secondary reactions lead to carbon enrichment of the final residue and are accompanied with an exothermic heat of reaction. The lower activation energies of the initiation and propagation reactions as compared to primary reactions (competitive reaction model consisting of weight loss and char forming reactions) confirm autocatalysis in large particles. The sealed reactor studies of small quantities of fine wood samples show that heterogeneous secondary reactions and not lower heating rates in large particles are the main source of char formed during the thermal decomposition of large wood particles. The model predictions are in agreement with the weight loss and temperature versus time curves over a wide range of particle size and furnace temperatures. 相似文献
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Malik R.J. Chand N. Nagle J. Ryan R.W. Alavi K. Cho A.Y. 《Electron Device Letters, IEEE》1992,13(11):557-559
Temperature-dependent measurements from 25 to 125°C have been made of the DC I -V characteristics of HBTs with GaAs and In0.53Ga0.47As collector regions. It was found that the GaAs HBTs have very low output conductance and high collector breakdown voltage BV CEO>10 V at 25°C, which increases with temperature. In striking contrast, the In0.53Ga0.47As HBTs have very high output conductance and low BV CEO~2.5 V at 25°C, which actually decreases with temperature. This different behavior is explained by the >104 higher collector leakage current, I CO, in In0.53Ga0.47As compared to GaAs due to bandgap differences. It is also shown that device self-heating plays a role in the I -V characteristics 相似文献
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The electrical conductivity of solution-grown poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) films doped with TCNQ, TCNE, TNF, and I2 has been studied as a function of dopant concentration, temperature (298–353 K), and field (50–2000 V). PPO forms a conductive complex on doping with these strong electron-acceptor organic molecules. As with PPO, two distinct ohmic and nonohmic conduction regions at low and higher fields, respectively, are observed. The conduction properties of doped PPo films result from the formation of an isotropic continuous charge-transfer complex. The existence of such a complex is confirmed by UV-visible absorption spectra measurements. A possible mechanism for the electrical conduction process is discussed. © 1994 John Wiley & Sons, Inc. 相似文献