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131.
We introduce two parameters, large-scale and small-scale rms roughness, to take into account the interface properties of thin films and multilayers in the calculation of their specular reflectance and transmittance. A theoretical motivation for the introduction of these two parameters instead of a standard single rms roughness is provided. Experimental power spectral density functions of several samples are used to illustrate ways in which the parameters introduced can be evaluated. 相似文献
132.
We describe a method to characterize spatial or temporal changes in the optical properties of turbid media using diffuse reflectance images acquired under broad-beam illumination conditions. We performed experiments on liquid phantoms whose absorption (mu(a)) and reduced scattering (mu(s)') coefficients were representative of those of biological tissues in the near infrared. We found that the relative diffuse reflectance R depends on mu(a) and mu(s)' only through the ratio mu(a)/mu(s)' and that dependence can be well described with an analytical expression previously reported in the literature [S. L. Jacques, Kluwer Academic Dordrecht (1996)]. We have found that this expression for R deviates from experimental values by no more than 8% for various illumination and detection angles within the range 0 degrees-30 degrees. Therefore, this analytical expression for R holds with good approximation even if the investigated medium presents curved or irregular surfaces. Using this expression, it is possible to translate spatial or temporal changes in the relative diffuse reflectance from a turbid medium into quantitative estimates of the corresponding changes of (mu(a)/mu(s)')(1/2). In the case of media with optical properties similar to those of tissue in the near infrared, we found that the changes mu(a)/mu(s)' should occur over a volume approximately 2 mm deep and 4 mm x 4 mm wide to apply this expression. 相似文献
133.
What predicts psychological resilience after disaster? The role of demographics, resources, and life stress. 总被引:1,自引:0,他引:1
Bonanno George A.; Galea Sandro; Bucciarelli Angela; Vlahov David 《Canadian Metallurgical Quarterly》2007,75(5):671
A growing body of evidence suggests that most adults exposed to potentially traumatic events are resilient. However, research on the factors that may promote or deter adult resilience has been limited. This study examined patterns of association between resilience and various sociocontextual factors. The authors used data from a random-digit-dial phone survey (N = 2,752) conducted in the New York City area after the September 11, 2001, terrorist attack. Resilience was defined as having 1 or 0 posttraumatic stress disorder symptoms and as being associated with low levels of depression and substance use. Multivariate analyses indicated that the prevalence of resilience was uniquely predicted by participant gender, age, race/ethnicity, education, level of trauma exposure, income change, social support, frequency of chronic disease, and recent and past life stressors. Implications for future research and intervention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
134.
Fouriezos George; Capstick Gary; Monette Fran?ois; Bellemare Christine; Parkinson Matthew; Dumoulin Angela 《Canadian Metallurgical Quarterly》2007,61(4):277
The flash-lag effect is a visual illusion wherein intermittently flashed, stationary stimuli seem to trail after a moving visual stimulus despite being flashed synchronously. We tested hypotheses that the flash-lag effect is due to spatial extrapolation, shortened perceptual lags, or accelerated acquisition of moving stimuli, all of which call for an earlier awareness of moving visual stimuli over stationary ones. Participants judged synchrony of a click either to a stationary flash of light or to a series of adjacent flashes that seemingly bounced off or bumped into the edge of the visual display. To be judged synchronous with a stationary flash, audio clicks had to be presented earlier--not later--than clicks that went with events, like a simulated bounce (Experiment 1) or crash (Experiments 2-4), of a moving visual target. Click synchrony to the initial appearance of a moving stimulus was no different than to a flash, but clicks had to be delayed by 30-40 ms to seem synchronous with the final (crash) positions (Experiment 2). The temporal difference was constant over a wide range of motion velocity (Experiment 3). Interrupting the apparent motion by omitting two illumination positions before the last one did not alter subjective synchrony, nor did their occlusion, so the shift in subjective synchrony seems not to be due to brightness contrast (Experiment 4). Click synchrony to the offset of a long duration stationary illumination was also delayed relative to its onset (Experiment 5). Visual stimuli in motion enter awareness no sooner than do stationary flashes, so motion extrapolation, latency difference, and motion acceleration cannot explain the flash-lag effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
135.
Kensinger Elizabeth A.; Gutchess Angela H.; Schacter Daniel L. 《Canadian Metallurgical Quarterly》2007,22(4):781
The effects of emotion on memory are often described in terms of trade-offs: People often remember central, emotional information at the expense of background details. The present experiment examined the effects of aging and encoding instructions on participants' ability to remember the details of central emotional objects and the backgrounds on which those objects were placed. When young and older adults passively viewed scenes, both age groups showed strong emotion-induced trade-offs. They were able to remember the visual details as well as the general theme of the emotional object, but they had difficulties remembering the visual specifics of the scene background. Age differences emerged, however, when participants were given encoding instructions that emphasized elaborative encoding of the entire scene. With these instructions, young adults overcame the trade-offs (i.e., they no longer showed impairing effects of emotion), whereas older adults continued to show good memory for the emotional object but poor memory for its background. These results suggest that aging impairs the ability to flexibly disengage attention from the negative arousing elements of scenes, preventing the successful encoding of nonemotional aspects of the environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
136.
Love Keisha M.; Bahner Angela D.; Jones Leslie N.; Nilsson Johanna E. 《Canadian Metallurgical Quarterly》2007,38(3):314
Graduate students in psychology typically report that they either love research or hate research. Despite the fact that most doctoral students in psychology enter some type of clinical practice upon graduation, research is a requirement for all students enrolled in scientist-practitioner programs regardless of their career aspirations beyond graduation. Research advances knowledge in the field of psychology and often guides clinical practice, yet very few psychologists conduct research after graduate school (C. J. Gelso, 1993). Efforts have been undertaken to determine factors that contribute to graduate students' research productivity. One such factor may be research self-efficacy. This study examined the influence of early research experience as a factor to bolster research self-efficacy. Results indicated that supportive peers and mentors contributed to positive research experiences. Additionally, positive team research experiences significantly predicted research self-efficacy. Implications for training programs and students are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
137.
138.
Angela Byrne 《EDPACS》2013,47(2):6-14
Abstract According to Richard Chambers, President and CEO of the Institute of Internal auditors (IIA), ideally internal audit should follow the risks. Yet as strategic business risks rank near the top of executive and audit committee concerns, Chief Audit Executives (CAEs) reported that such risks account for only 4 percent of audit plan coverage overall. It is not surprising that strategic risk is top of mind for boards and senior management. As regulators around the world increase expectations, many suggest objective, independent evaluation is a critical component that boards should take advantage of in fulfilling their oversight role. These developments present tremendous opportunity for internal auditors to provide much needed assurance on strategic risk. Taking advantage of this opportunity requires that internal auditors not only apply their expertise in effective risk governance, but also demonstrate their knowledge of strategy, and perhaps more importantly, their understanding of the relationship between risk and strategy. Given the changing landscape of the field of strategy and risk management, some internal auditors may feel that contributing to strengthening this area is beyond their capacity. However many tools are available to support auditors. Developing competency requires not only knowledge of the organization's strategy and associated risks, but also staying current on emerging thinking and best practices in the field of strategy and risk management as well as emerging expectations of regulators and standard setters. Providing assurance on strategic risk is a challenge, however one that is within our grasp through thoughtful, deliberate planning and action. 相似文献
139.
Even when instructors take steps to mitigate conflict between students, online discussions are likely to be more emotional than face-to-face discussions, and student posts frequently bear characteristics of ranting. This paper uses a model from the field of psycholinguistics to identify linguistic features that writers use to communicate emotion in CMC to substitute for the nonverbal emotional cues that speakers and listeners rely on in face-to-face conversation. Our analysis of the online forum for a course called Presidential Election Rhetoric illustrates not only that students use linguistic features to express emotion but also that they transmit emotion to one another through the use of these features. Additionally, we suggest that students’ unfamiliarity expressing emotion subtly and accurately using linguistic features contributes to the quality of ranting in CMC. Finally, we recommend specific strategies to help students further hone their skills at expressing and perceiving emotion in CMC. 相似文献
140.