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101.
Jan Mulkens Bob Streefkerk Hans Jasper Jos de Klerk Fred de Jong Leon Levasier Martijn Leenders 《电子工业专用设备》2008,37(3):13-19
论述了第五世代双扫描平台浸液式扫描曝光机的性能和进展。表明了在高速扫描状态下有生产价值的套刻和聚焦性能的实现。浸液式设备更多的关键部分与缺陷有关,而且该机的改进是通过有生产价值的缺陷水平方面来体现的。为了保持这种缺陷水平的改进效果,需要在圆片应用中进行专门稳定的测量。特加是边缘空泡除去(EBR)设计和圆片斜面良流线性是很重要的。 相似文献
102.
Energy Harvesting: Electric Field Assisted Microfluidic Platform for Generation of Tailorable Porous Microbeads as Cell Carriers for Tissue Engineering (Adv. Funct. Mater. 20/2018) 下载免费PDF全文
103.
Paul Sonntag Jan Haschke Sven Kühnapfel Tim Frijnts Daniel Amkreutz Bernd Rech 《Progress in Photovoltaics: Research and Applications》2016,24(5):716-724
We present an interdigitated back‐contact silicon heterojunction system designed for liquid‐phase crystallized thin‐film (~10 µm) silicon on glass. The preparation of the interdigitated emitter (a‐Si:H(p)) and absorber (a‐Si:H(n)) contact layers relies on the etch selectivity of doped amorphous silicon layers in alkaline solutions. The etch rates of a‐Si:H(n) and a‐Si:H(p) in 0.6% NaOH were determined and interdigitated back‐contact silicon heterojunction solar cells with two different metallizations, namely Al and ITO/Ag electrodes, were evaluated regarding electrical and optical properties. An additional random pyramid texture on the back side provides short‐circuit current density (jSC) of up to 30.3 mA/cm2 using the ITO/Ag metallization. The maximum efficiency of 10.5% is mainly limited by a low of fill factor of 57%. However, the high jSC, as well as VOC values of 633 mV and pseudo‐fill factors of 77%, underline the high potential of this approach. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
104.
Huizenga HM de Munck JC Waldorp LJ Grasman RP 《IEEE transactions on bio-medical engineering》2002,49(6):533-539
A method is described to incorporate the spatiotemporal noise covariance matrix into a spatiotemporal source analysis. The essential feature is that the estimation problem is split into two parts. First, a model is fitted to the observed noise covariance matrix. This model is a Kronecker product of a spatial and a temporal matrix. The spatial matrix models the spatial covariances by a function dependent on sensor distance. The temporal matrix models the temporal covariances as lag dependent. In the second part, sources are estimated given this noise model, which can be done very efficiently due to the Kronecker formulation. An application to real electroencephalogram (EEG) data shows that the noise model fits the data very well. Simulation results show that the resulting source estimates are more precise than those obtained from a standard analysis neglecting the noise covariance. In addition, the estimated standard errors of the source parameter estimates are far more precise than those obtained from a standard analysis. Finally, the source parameter standard errors are used to investigate the effects of temporal sampling. It is shown that increasing the sampling by a factor x, decreases the standard errors of all source parameters with the square root of x. 相似文献
105.
W.-R. Liou T.-H. Chen M.-L. Yeh J.-J. Ho G. E. Jan 《International Journal of Electronics》2013,100(6):623-632
A fully integrated dual-band LC voltage control oscillator, designed in a 0.18-µm CMOS technology for 5.8-GHz/2.0-GHz wireless communication applications, is described. The frequency band switching is accomplished with switched-inductor technique. The dual-band oscillator can be operated in 5.38–6.23?GHz and 1.78–2.07?GHz with 15% frequency tuning range. Two different inductors are used for the frequency band switching. Frequency tuning is implemented by varying the capacitance of a MOS varactor. The measured phase noise is ?109?dBc/Hz @ 1?MHz and ?112?dBc/Hz @ 1?MHz for frequency at 5.8?GHz and 2?GHz, respectively. This oscillator is fabricated in UMC's 0.18-µm one-poly-six-metal 1.8?V process. The power dissipation of this dual-band VCO is 11.7 and 9.3?mW for oscillation frequency of 2?GHz and 5.8?GHz, respectively. 相似文献
106.
Lode Nachtergaele Toon Gijbels Jan Bormans Francky Catthoor Ivo Bolsens 《The Journal of VLSI Signal Processing》2001,27(1-2):161-169
Upcoming multi-media compression applications will require high memory bandwidth. In this paper, we estimate that a software reference implementation of an MPEG-4 video decoder typically requires 200 Mtransfers/s to memory to decode 1 CIF (352×288) Video Object Plane (VOP) at 30 frames/s. This imposes a high penalty in terms of power but also performance.However, we also show that we can heavily improve on the memory transfers, without sacrificing speed (even gaining about 10% on cache misses and cycles for a DEC Alpha), by aggressive code transformations. For this purpose, we have manually applied an extended version of our data transfer and storage exploration (DTSE) methodology, which was originally developed for custom hardware implementations. 相似文献
107.
In this paper, we present a methodology to design filters for an imaging system to improve the accuracy of the spectral measurements for families of reflective surfaces. We derive the necessary and sufficient conditions that the sensor space of the system must obey in order to measure the spectral reflectance of the surfaces accurately. Through simulations, we show how these conditions can be applied to design filters using a set of sample spectral data acquired from extracted teeth. For this set of data, we also compare our results to those of Wolski's method, a conventional filter design method which produces filters that recover tristimulus values of surfaces accurately under several illuminants. We show that our method produces filters that capture the spectral reflectance better given the same number of measurements. The errors in predicting the color of the sample data are much lower under every test illuminant when the filters designed with our method are used. 相似文献
108.
Alexander J.A.M. van Deursen Jan A.G.M. van Dijk Peter M. ten Klooster 《Telematics and Informatics》2015
We investigate types of Internet activities among a representative sample of the Dutch population from 2010 to 2013. We examined usage patterns of seven types of Internet activities (i.e., information, news, personal development, commercial transaction, social interaction, leisure, and gaming) and related these patterns with gender, age, education, and income. Activities related to news, personal development, commercial transaction, and social interaction increased in popularity. For most capital enhancing activities, men, younger people, higher educated people, and people with higher than average incomes were prominent. These observations, however, are subject to change. The Internet seems to provide increasingly more capital-enhancing opportunities for those with higher education and income, which would accordingly reinforce their already strong positions in society. 相似文献
109.
Cédric Rolin Karolien Vasseur Björn Niesen Myriam Willegems Robert Müller Sören Steudel Jan Genoe Paul Heremans 《Advanced functional materials》2012,22(23):5050-5059
Compared to traditional vacuum evaporation techniques for small organic molecules, organic vapor phase deposition (OVPD) possesses a extra processing parameter: the pressure of process gas Pch. Here, the influence of large Pch variations (from 0.1 mbar to atmospheric pressure) on pentacene thin film growth is explored. OVPD operation at higher Pch is characterized by lower carrier gas velocities and lower organic diffusivities. These result in an invariance of the material utilization efficiency over the entire pressure span and in an advantageous equilibrium evaporation regime in the source. An increase in Pch yields rough pentacene layers. Classical nucleation theory is applied to demonstrate how the pressure rise triggers homogeneous nucleation in the gas phase, causing the observed roughening. The use of lower deposition rates, higher dilution flow rates, and higher substrate temperatures result in the suppression of gas phase nucleation and the growth of smooth pentacene films at atmospheric pressure. Using these optimized conditions, state‐of‐the‐art pentacene thin film transistors with saturation mobilities above 0.9 cm2/Vs are reproducibly fabricated. p‐Type circuits are also made and a 19‐stage ring oscillator with a stage delay of 51 μs at a supply voltage of 15 V is demonstrated. 相似文献
110.
Chenjie Han Yeqing Lyu Shaona Wang Biao Liu Yi Zhang Jan J. Weigand Hao Du Jun Lu 《Advanced functional materials》2023,33(46):2305436
Using ethanol electrocatalytic oxidation reaction (EOR) with a lower reaction potential to replace oxygen evolution reaction (OER) and integrating hydrogen evolution reaction (HER) have a promising development prospect for more energy-saving electrolytic hydrogen production. However, the main challenges of EOR are insufficient catalytic activity, high overpotential, and slow kinetics. Active sites on the electrocatalysts surface are occupied by alkali metal ion hydrate clusters by noncovalent interactions, which is considered to be one of the major causes of these challenges. To reduce the effect of the noncovalent interactions on the catalytic activity of the electrocatalyst, copper is chosen and doped in the form of a single atom in the electrocatalyst (Pt@Cu/C) to increase the electrocatalyst conductivity and make the anode contain more positive charge in this study. Then, alkali metal ion hydrate clusters are difficult to adsorb at the active site of Pt@Cu/C. The EOR electrocatalytic activity of Pt@Cu/C is up to 8184 mA mgPt−1, which is ≈4.8 times as high as that of Pt/C. The two-electrode hydrogen production device using Pt@Cu/C as anode for coupled EOR&HER requires a smaller voltage of 0.60 V to reach 10 mA cm−2 compared with that of Pt/C (0.76 V). 相似文献