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91.
Visualization with OpenGL: 3D made easy 总被引:1,自引:0,他引:1
This article addresses a freely available application programming interface (API) for three-dimensional graphics, known as OpenGL. This API bridges the gap between piles of raw data and extremely complicated three-dimensional animation in a way that requires only a few hours to learn. It is can be used for EM field visualization. In this article, we try to take most of the “leg-work” out of learning OpenGL, by presenting a tutorial that will get you started in the right direction. Some other interesting OpenGL-related technologies are also mentioned 相似文献
92.
We have found the local temporal shot-to-shot variation of the NIF high-energy laser system to be relatively constant (~3.4% to 4.2% of the mean fluence). We have developed a statistical model that predicts the maximum fluence distribution any particular location will be exposed to after N independent shots (the so-called max-of-N fluence distribution) using the measured shot-to-shot variance; this method allows for an estimate of maximum optics fluence exposure. 相似文献
93.
A histochemical technique has been used in scanning electron microscopy to localize specific areas in biological material. The specific contrast introduced by the staining procedure depends on the interaction of complex variables such as the coating material, the accelerating voltage and the use of a primary or secondary electron signal. 相似文献
94.
Between July, 1993, and October, 1994, seven cases were examined that consisted of increased mortality in commercial turkeys due to cellulitis. The condition started at 13-16 wk of age in toms and persisted until the birds were marketed. The mortality rate was 1-2% per week. Lesions began on the ventrum of the tail and consisted of swelling and the formation of vesiclelike structures. Most of the affected birds also had an accumulation of gelatinous fluid in the subcutis of the tail and breast areas. The underlying musculature was often darkened or petechiated. Clostridium perfringens type A was isolated from two of the cases. Lesions similar to those found in the field were reproduced experimentally in turkeys injected with the subcutaneous fluid obtained from birds in field cases. 相似文献
95.
96.
M Robain N Carré E Dussaix D Salmon-Ceron L Meyer 《Canadian Metallurgical Quarterly》1998,25(9):476-480
BACKGROUND: Data on incidence of cytomegalovirus (CMV) seroconversion in HIV-infected (HIV(+)) subjects was sparse. GOAL: To determine the incidence of CMV seroconversion in sexually active HIV(+) subjects and sexual factors associated with CMV seroconversion. STUDY DESIGN: One hundred eighty four persons not infected by CMV at enrollment in a cohort of HIV(+) persons were studied. A case-control study within the cohort was conducted to determine the effect of sexual behavior in the 6 months prior to CMV seroconversion. Thirty seven cases of CMV seroconversion were compared with 136 controls. RESULTS: The overall incidence of CMV seroconversion was 9.18 per 100 person-years (95% confidence interval (CI), 6.67-12.28) and was particularly high among homosexual men. After adjustment for age, socio-professional category, sexual orientation, and casual sex, the risk of CMV seroconversion was higher in subjects who never used condoms than in those who used them systematically (adjusted odds ratio (OR) 3.37;95% CI, 1.05-11.00). CONCLUSIONS: In addition to the need to protect their sexual partners from HIV infection, HIV(+) subjects free of CMV infection should use condoms to avoid CMV infection and its complications. 相似文献
97.
Lyle H. Lanier was at the core an experimental psychologist who exerted influence on psychology at large by both his research and his administrative endeavors. Lanier passed away at his retirement home, in Phoenix, Arizona, on December 30, 1988. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
Precious metal threads from a XVIth century tapestry were visually classified using optical microscopy and scanning electron microscopy (SEM). The nature of the surface metals and the nature of the corrosion products were studied by Energy dispersive X-ray analysis (EDX) and dynamic secondary ion mass spectrometry (SIMS).The cleaning of metal artefacts by UV/Ozone treatment was investigated and the surface properties before and after UVO treatment were determined by SIMS. 相似文献
99.
100.
DP Phillips TL Taylor SE Hall MM Carr JE Mossop 《Canadian Metallurgical Quarterly》1997,101(6):3694-3705
This article describes four experiments on gap detection by normal listeners, with the general goal being to examine the consequences of using noises in different perceptual channels to delimit a silent temporal gap to be detected. In experiment 1, subjects were presented with pairs of narrow-band noise sequences. The leading element in each pair had a center frequency of 2 kHz and the trailing element's center frequency was parametrically varied. Gap detection thresholds became increasingly poor, sometimes by up to an order of magnitude, as the spectral disparity was increased between the noise bursts that marked the gap. These data suggested that gap-detection performance is impoverished when the underlying perceptual timing operation requires a comparison of activity in different perceptual channels rather than a discontinuity detection within a given channel. In experiment 2, we assessed the effect of leading-element duration in within-channel and between-channel gap detection tasks. Gap detection thresholds rose when the duration of the leading element was less than about 30 ms, but only in the between-channel case. In experiment 3, the gap-detection stimulus was redesigned so that we could probe the perceptual mechanisms that might be involved in stop consonant discrimination. The leading element was a wideband noise burst, and the trailing element was a 300-ms bandpassed noise centered on 1.0 kHz. The independent variable was the duration of the leading element, and the dependent variable was the smallest detectable gap between the elements. When the leading element was short in duration (5-10 ms), gap thresholds were close to 30 ms, which is close to the voice onset time that parses some voiced from unvoiced stop consonants. In experiment 4, the generality of the leading-element duration effect in between-channel gap detection was examined. Spectrally identical noises defining the leading and trailing edges of the gap were presented to the same or to different ears. There was a leading-element duration effect only for the between channel case. The mean gap threshold was again close to 30 ms for short leading-element durations. Taken together, the data suggest that gap detection requiring a temporal correlation of activity in different perceptual channels is a fundamentally different task to the discontinuity detection used to execute gap detection performance in the traditional, within-channel paradigm. 相似文献