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1.
This paper highlights the role of the faculty member in recruiting students currently enrolled in B.S. programs in engineering and the sciences into full-time pursuit of a graduate-level engineering degree. The faculty member is demonstrated to be in a unique position to influence such students, providing strong counterforces to a confluence of attitudes and pressures experienced during the B.S. experience which effectively create a barrier to full-time engineering graduate study. We analyze this barrier via the method of force field analysis, and demonstrate that effective recruitment into full-time graduate study must be based on a four-fold strategy of education, expectations, improved B.S. experience and better control of the B.S. environment. Approaches to implement these strategies are discussed.  相似文献   
2.
随着消费意识在中国——这个世界上人口最多的国度逐渐形成,许多专业投资者正将关注的目光从中国的出口制造商转向以国内为重点的商品和服务提供商。  相似文献   
3.
The rapidly increasing solar conversion efficiency (PCE) of hybrid organic–inorganic perovskite (HOIP) thin-film semiconductors has triggered interest in their use for direct solar-driven water splitting to produce hydrogen. However, application of these low-cost, electronic-structure-tunable HOIP tandem photoabsorbers has been hindered by the instability of the photovoltaic-catalyst-electrolyte (PV+E) interfaces. Here, photolytic water splitting is demonstrated using an integrated configuration consisting of an HOIP/n+silicon single junction photoabsorber and a platinum (Pt) thin film catalyst. An extended electrochemical (EC) lifetime in alkaline media is achieved using titanium nitride on both sides of the Si support to eliminate formation of insulating silicon oxide, and as an effective diffusion barrier to allow high-temperature annealing of the catalyst/TiO2-protected-n+silicon interface necessary to retard electrolytic corrosion. Halide composition is examined in the (FA1-xCsx)PbI3 system with a bandgap suitable for tandem operation. A fill factor of 72.5% is achieved using a Spiro-OMeTAD-hole-transport-layer (HTL)-based HOIP/n+Si solar cell, and a high photocurrent density of −15.9 mA cm−2 (at 0 V vs reversible hydrogen electrode) is attained for the HOIP/n+Si/Pt photocathode in 1 m NaOH under simulated 1-sun illumination. While this thin-film design creates stable interfaces, the intrinsic photo- and electro-degradation of the HOIP photoabsorber remains the main obstacle for future HOIP/Si tandem PEC devices.  相似文献   
4.
Cylindrical stand-alone tubes of plasma-sprayed alumina were tested in uniaxial compression at room temperature, using strain gages to monitor axial strains. The effect of lamella size on the mechanical response was investigated by employing different starting powders to fabricate samples. The average powder sizes investigated included 9 m, 19 m and 32 m alumina; the resulting effective lamella diameters were 10 m, 28 m, and 55 m, respectively. Similar stress-strain hysteresis was observed on unloading in all tubes, independent of lamella size. A strong correlation between the failure stress and the cumulative strain at failure was also observed for tubes fabricated from the three powders. For samples with approximately constant densities, tubes plasma sprayed with the 9 m powder exhibited greater moduli than tubes sprayed from either 19 or 32 m powders. This difference was attributed to the greater percentage of unmelted -Al2O3 in the coating.  相似文献   
5.
Two experiments examined the role of valuing the welfare of a person in need as an antecedent of empathic concern. Specifically, these experiments explored the relation of such valuing to a well-known antecedent--perspective taking. In Experiment 1, both perspective taking and valuing were manipulated, and each independently increased empathic concern, which, in turn, increased helping behavior. In Experiment 2, only valuing was manipulated. Manipulated valuing increased measured perspective taking and, in part as a result, increased empathic concern, which, in turn, increased helping. Valuing appears to be an important, largely overlooked, situational antecedent of feeling empathy for a person in need. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
7.
Social learning theory has produced a three-step model of prosocial development: In the young child, prosocial behavior is elicited by material rewards; in the older child, it is elicited also by social rewards; and in the morally mature adult, it is elicited by self-rewards based on an internalized perception of oneself as a kind, caring, altruistic individual. Self-perception theory has complicated this social learning model by demonstrating that once the third step is reached, the continued presence of material and social rewards may undermine intrinsic prosocial motivation based on self-rewards, producing moral regression. We propose a further complication. Critical self-reflection—the desire to know thyself—may introduce a self-deprecating attributional bias that can undermine self-perceived altruism, even following helping for which one receives only intrinsic self-rewards. Two experiments are reported in which we manipulated critical self-reflection on one's reasons for helping. Results indicated that self-reflection undermined self-perceived altruism, especially when the salience of the self-rewards for helping was high. Experiment 2 also provided evidence that, as predicted, this self-reflection effect was most apparent for individuals who valued self-knowledge more highly than concern for others. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Honeybees were classically conditioned with odor as conditioned stimulus/stimuli (CS), sucrose as unconditioned stimulus/stimuli (UCS), and proboscis extension as response. The purpose of Exp 1 (Ns?=?26 and 27) was to look for facilitation of forward conditioning by CS–UCS overlap, but rapid conditioning without overlap left little room for improvement. In 2 further experiments, CS and UCS were simultaneous, and response to odor alone was measured in subsequent tests. In Exp 2, a simultaneous group (N?=?25) responded more to the training odor than did an unpaired control group (N?=?25). In Exp 3, a differentially conditioned simultaneous group (N?=?29) responded more to an odor paired with sucrose in training (S+) than to an odor presented alone (S–). The implications of the results for the problem of the role of amount of reward in honeybee learning are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Tested the prediction that being more religious in one way—as an intrinsic end in itself—would be associated with displaying less racial prejudice when the prejudice was overt, but not when it was covert. It was also predicted that being more religious in another way—as an open-end quest—would be associated with displaying less racial prejudice even when the prejudice was covert. An attributional ambiguity technique developed by M. L. Snyder et al (see record 1981-05489-001) was used. 44 White undergraduates interested in religion chose between sitting with a Black person or a White person to watch a movie. In the overt prejudice condition, the same movie was being shown in both locations; in the covert prejudice condition, 2 movies were being shown. Although not all predicted relations were statistically reliable, the pattern of correlations was consistent with both predictions. An intrinsic orientation to religion was significantly negatively correlated with choosing to sit with the White person in the overt condition, but this correlation was close to zero in the covert condition. Only the quest orientation to religion was significantly negatively correlated with choosing to sit with the White person in the covert condition. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Tested the claim of R. L. Archer et al (see record 1982-05783-001) that empathy leads to increased helping only under socially evaluative circumstances. In Exp I, 22 female undergraduates were led to believe that no one (including the person in need) would ever know if they declined to help. In this situation, which was designed to be devoid of the potential for negative social evaluation for not helping, there was still a positive relationship between self-reported empathic emotion and offering help. In Exp II, empathy (low vs high) and social evaluation (low vs high) were manipulated with 32 Ss. Once again there was a positive relationship between empathy and offering help when the potential for social evaluation was low as well as high. Results of both studies suggest that the motivation to help evoked by empathy is not egoistic motivation to avoid negative social evaluation. Instead, the observed pattern was what would be expected if empathy evokes altruistic motivation to reduce the victim's need. (23 ref) (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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