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131.
132.
We conducted two studies to examine perceptions of, and reactions to, ostracism occurring either in-person or online. In study 1, participants read a vignette describing either in-person or online ostracism, then estimated their psychological and interpersonal responses as if they experienced such ostracism. Participants anticipated experiencing distress, and this was consistent across ostracism method. Ostracism method did predict negative affect (NA), with greater NA increases anticipated for in-person exclusion, compared to online. A significant interaction between gender and ostracism method predicted anticipated belonging. Males anticipated higher belonging in the in-person condition (relative to online); females anticipated more belonging in the online condition. In study 2, participants experienced in-person or online ostracism during a brief interaction with study confederates. Both conditions elicited similar reports of low inclusion, high exclusion, and significant decreases in positive and negative affect. Ostracism method qualified self-esteem (SE) results; chat room participants indicated an increase in SE following ostracism, whereas in-person participants reported a slight decrease. Males and females were similarly affected by both conditions. These studies demonstrate that online experiences of ostracism may be as meaningful as those experienced in person. Whether this finding generalizes to those with less technological familiarity should be examined further. 相似文献
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135.
A tandem ensemble of two 4.5-m-long x 0.25-mm-i.d. capillary columns with the first using a 0.50-microm film of nonpolar dimethyl polysiloxane and the second using a 0.25-microm film of polar trifluoropropylmethyl polysiloxane is operated with atmospheric pressure air as the carrier gas and an outlet pressure of 50.5 kPa established using a small vacuum pump. A thicker stationary-phase film is used in the first column to increase retention for very volatile compounds. This significantly increases the resolution of these compounds. The thicker film in the first (nonpolar) column decreases the polarity of the tandem column ensemble and, thus, changes its selectivity. A low-dead-volume valve, connected between the column junction point and a source of atmospheric pressure air, is used to obtain pulsed modulation of the carrier gas flow through the column ensemble. When the valve is open, the ensemble inlet pressure and the junction-point pressure are nearly the same, and carrier gas flow nearly stops in the first column, and flow in the second column increases. Enhanced resolution of a component pair that is separated by the first column but coelutes from the column ensemble can be obtained if the valve is opened for a few seconds after one of the components has crossed the junction and is in the second column, but the other component is still in the first column. A sequence of appropriately timed pulses is used to obtain enhanced resolution of several pairs of components that coelute from the column ensemble. These methods enabled the complete separation of an 18-component vapor mixture of common solvents in air in 3.5 min. 相似文献
136.
The heat of combustion of two distinctly synthesized stoichiometric tantalum-tungsten oxide energetic composites was investigated by bomb calorimetry. One composite was synthesized using a sol-gel (SG) derived method in which micrometric-scale tantalum is immobilized in a tungsten oxide three-dimensional nanostructured network structure. The second energetic composite was made from the mixing of micrometric-scale tantalum and commercially available (CA) nanometric tungsten oxide powders. The energetic composites were consolidated using the spark plasma sintering (SPS) technique under a 300 MPa pressure and at temperatures of 25, 400, and 500 °C. For samples consolidated at 25 °C, the density of the CA composite is 61.65 ± 1.07% in comparison to 56.41 ± 1.19% for the SG derived composite. In contrast, the resulting densities of the SG composite are higher than the CA composite for samples consolidated at 400 and 500 °C. The theoretical maximum density for the SG composite consolidated to 400 and 500 °C are 81.30 ± 0.58% and 84.42 ± 0.62%, respectively. The theoretical maximum density of the CA composite consolidated to 400 and 500 °C are 74.54 ± 0.80% and 77.90 ± 0.79%, respectively. X-ray diffraction analyses showed an increase of pre-reaction of the constituents with an increase in the consolidation temperature. The increase in pre-reaction results in lower stored energy content for samples consolidated to 400 and 500 °C in comparison to samples consolidated at 25 °C. 相似文献
137.
Joshua P. Schwarz Ruimin Liu David B. Newell Richard L. Steiner Edwin R. Williams Douglas Smith Ali Erdemir John Woodford 《Journal of research of the National Institute of Standards and Technology》2001,106(4):627-640
The NIST watt balance experiment is being completely rebuilt after its 1998 determination of the Planck constant. That measurement yielded a result with an approximately 1×10−7 relative standard uncertainty. Because the goal of the new incarnation of the experiment is a ten-fold decrease in uncertainty, it has been necessary to reexamine many sources of systematic error. Hysteresis effects account for a substantial portion of the projected uncertainty budget. They arise from mechanical, magnetic, and thermal sources. The new experiment incorporates several improvements in the apparatus to address these issues, including stiffer components for transferring the mass standard on and off the balance, better servo control of the balance, better pivot materials, and the incorporation of erasing techniques into the mass transfer servo system. We have carried out a series of tests of hysteresis sources on a separate system, and apply their results to the watt apparatus. The studies presented here suggest that our improvements can be expected to reduce hysteresis signals by at least a factor of 10—perhaps as much as a factor of 50—over the 1998 experiment. 相似文献
138.
Joshua Israelsohn 《电子设计技术》2005,12(6):62-62,64,66,68,70
几十年的工艺开发大多着眼于提高逻辑电路的密度与速度。最小门尺寸已经从微米级缩小到100nm以下。然而,我们周围的世界并没有同步缩小,所以,对许多应用来说,信号、噪声和非周期事件仍与过去一样大或者更大。作为I/O设计师该怎么办? 相似文献
139.
A surge of research has been conducted to examine memory editing mechanisms that help distinguish accurate from inaccurate memories. In the present experiment, the authors examined the ability of participants to use novelty detection, recollection rejection, and plausibility judgments to reject lures presented on a recognition memory test. Participants studied a list of word pairs that were arranged in a category relationship (both words from the same category) or an unrelated relationship (both words from different categories) under full or divided attention. At test, participants were given a yes/no recognition test in which they were to respond after seeing the test items for 400 ms or 2,800 ms. Some of the test items were rearranged word pairs that were consistent with the study relationship, whereas others were inconsistent with the study relationship. The results demonstrate that the participants required full attention at study to use novelty detection, recollection rejection, and plausibility judgments to reject lures. Moreover, the results indicate that a long response deadline at test was needed for participants to use both recollection rejection and plausibility judgments to reject lures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
140.
Joshua Meyrowitz 《The Journal of communication》2008,58(4):641-663