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Irwin G. Priest 《Journal of the American Oil Chemists' Society》1928,5(3):63-73
This paper reports primarily upon tests of the color sense of about thirty men who have had large experience in the color grading of vegetable oils in terms of Lovibond glasses, nearly all of these men being members of the American Oil Chemists’ Society. Similar tests on five other observers are also included for comparison. All of the oil chemists were first tested by the Stilling Chart test, but the results by this test (although reported) are not the principal matter of interest. This test was regarded merely as preliminary, serving to discover any gross abnormality of color sense. The tests of specific interest relate to the observer’s ability to report correctly very small differences in Lovibond red at 35 yellow 7.6 red on the Lovibond scale, brightness diffences being eliminated so that the judgment depends, in effect, entirely upon the observer’s sensibility to difference in dominant wave length at equal brightness. The subject’s ability in this regard was tested by the well known psycho-physical method of “right and wrong answers.” The results for each observer are expressed so as to show the probability of his perceiving correctly given small differences in Lovibond red, under certain specified conditions. The chief results may be summarized as follows:
- 1.A difference of 0.1 red at 35 yellow 7.6 red is perceivedwith certainty by only very few exceptional observers. However, this difference is perceptible in the sense that its presence does affect the observer’s judgmentin the average, although he is very doubtful of the reality of such a difference. 相似文献
76.
Irwin W. Sandberg 《Circuits, Systems, and Signal Processing》2000,19(5):385-398
It is shown that thePQ theorem can be used to solve a certain signal recovery problem in which the transmitted and received signals are almost periodic functions. In this problem the signal to be recovered, which is bandlimited, is nonlinearly distorted and then bandlimited to the original band. Related signal recovery results are also given. These related results, unlike thePQ theorem, are applicable in settings in which the underlying signal space is not a Hilbert space or even a space that is complete. 相似文献
77.
Alexander W. Hains Jun Liu Alex B. F. Martinson Michael D. Irwin Tobin J. Marks 《Advanced functional materials》2010,20(4):595-606
The effects of anode/active layer interface modification in bulk‐heterojunction organic photovoltaic (OPV) cells is investigated using poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and/or a hole‐transporting/electron‐blocking blend of 4,4′‐bis[(p‐trichlorosilylpropylphenyl)‐phenylamino]biphenyl (TPDSi2) and poly[9,9‐dioctylfluorene‐co‐N‐[4‐(3‐methylpropyl)]‐diphenylamine] (TFB) as interfacial layers (IFLs). Current–voltage data in the dark and AM1.5G light show that the TPDSi2:TFB IFL yields MDMO‐PPV:PCBM OPVs with substantially increased open‐circuit voltage (Voc), power conversion efficiency, and thermal stability versus devices having no IFL or PEDOT:PSS. Using PEDOT:PSS and TPDSi2:TFB together in the same cell greatly reduces dark current and produces the highest Voc (0.91 V) by combining the electron‐blocking effects of both layers. ITO anode pre‐treatment was investigated by X‐ray photoelectron spectroscopy to understand why oxygen plasma, UV ozone, and solvent cleaning markedly affect cell response in combination with each IFL. O2 plasma and UV ozone treatment most effectively clean the ITO surface and are found most effective in preparing the surface for PEDOT:PSS deposition; UV ozone produces optimum solar cells with the TPDSi2:TFB IFL. Solvent cleaning leaves significant residual carbon contamination on the ITO and is best followed by O2 plasma or UV ozone treatment. 相似文献
78.
An 11-Bit 8.6 GHz Direct Digital Synthesizer MMIC With 10-Bit Segmented Sine-Weighted DAC 总被引:1,自引:0,他引:1
Geng X. Dai F. F. Irwin J. D. Jaeger R. C. 《Solid-State Circuits, IEEE Journal of》2010,45(2):300-313
79.
Wei-lun Hung Yuan Xie Narayanan Vijaykrishnan Mahmut Kandemir Mary Jane Irwin 《Journal of Signal Processing Systems》2010,58(2):145-160
Power consumption is a top priority in high performance circuit design today. Many low power techniques have been proposed
to tackle the ever serious, highly pressing power consumption problem, which is composed of both dynamic and static power
in the nanometer era. The static power consumption nowadays receives even more attention than that of dynamic power consumption
when technology scales below 100 nm. In order to mitigate the aggressive power consumption, various existing low power techniques
are often used; however, they are often applied independently or combined with two or at most three different techniques together,
and that is not sufficient to address the escalating power issue. In this paper, we present a power optimization framework
for the minimization of total power consumption in combinational logic through multiple V
dd
assignment, multiple V
th
assignment, device sizing, and stack forcing, while maintaining performance requirements. These four power reduction techniques
are properly encoded into the genetic algorithm and evaluated simultaneously. The overhead imposed by the insertion of level
converters is also taken into account. The effectiveness of each power reduction mechanism is verified, as are the combinations
of different approaches. Experimental results are presented for a number of 65 nm benchmark circuits that span typical circuit
topologies, including inverter chains, SRAM decoders, multiplier, and a 32 bit carry adder. Our experiments show that the
combination of four low power techniques is the effective way to achieve low power budget. The framework is general and can
be easily extended to include other design-time low power techniques, such as multiple gate length or multiple gate oxide
thickness. 相似文献
80.
Dispersal of beer on a commercially available tube of kieselguhr and elution with dichloromethane was found to be a much faster and more efficient method of obtaining a beer flavour extract than liquid-liquid extraction. The constitution of each type of extract was qualitatively similar. The use of an internal standard allowed major flavour components to be quantitatively analysed. 相似文献