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991.
The comprehensive functionality and nontrivial design of realistic general-purpose container libraries pose challenges to formal verification that go beyond those of individual benchmark problems mainly targeted by the state of the art. We present our experience verifying the full functional correctness of EiffelBase2: a container library offering all the features customary in modern language frameworks, such as external iterators, and hash tables with generic mutable keys and load balancing. Verification uses the automated deductive verifier AutoProof, which we extended as part of the present work. Our results indicate that verification of a realistic container library (135 public methods, 8400 LOC) is possible with moderate annotation overhead (1.4 lines of specification per LOC) and good performance (0.2 s per method on average). 相似文献
992.
Mueser Kim T.; Rosenberg Stanley D.; Fox Lindy; Salyers Michelle P.; Ford Julian D.; Carty Patricia 《Canadian Metallurgical Quarterly》2001,13(1):110
Interrater reliability, internal consistency, test-retest reliability, and convergent validity were examined for the Trauma History Questionnaire (THQ), the Clinician-Administered Posttraumatic Stress Disorder (PTSD) Scale (CAPS), and the PTSD Checklist (PCL) in 30 clients with severe mental illnesses. Interrater reliability for the THQ and CAPS was high, as was internal consistency of CAPS and PCL subscales. The test-retest reliability of the THQ was moderate to high for different traumas. PTSD diagnoses on the CAPS and PCL showed moderate test-retest reliability. Lower levels of test-retest reliability for PTSD diagnoses were related to psychosis diagnoses and symptoms. However, when more stringent criteria for PTSD were used on the CAPS, it had excellent test-retest reliability across all clients. CAPS and PCL diagnoses of PTSD showed moderate convergent validity. The results support the reliability of trauma and PTSD assessments in clients with severe mental illness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Julian Szekely 《Metallurgical and Materials Transactions B》1988,19(3):525-540
A brief review is presented of the current state of extractive metallurgy, and it is shown that it is still a significant
part of the national economy. Then a definition is given of mathematical models, and the general philosophy of modeling is
discussed, together with the cost of models, hardware, and software options. Several illustrative examples are given, drawn
from aluminum electrolysis, flash smelting, tundish operations, and plasma systems. The paper is concluded with the future
modeling tasks facing us; these include the more widespread applications of models to represent both existing and new processing
operations. It is stressed that models can play a major role in developing a holistic approach to metals and materials processing,
where the primary extraction and refining operations are combined with the final processing steps. 相似文献
994.
SJ Ryde R Eston MA Laskey CJ Evans DA Hancock 《Canadian Metallurgical Quarterly》1998,49(5-6):507-509
The measurement of body fat in ten subjects (BMI from 22 to 43 kg/m2), and in particular the changes arising from a ketogenic diet, by the techniques of in vivo neutron activation analysis (NAA), densitometry (using two- and four-compartment models) by under water weighing (UWW) and dual energy X-ray absorptiometry (DXA) was compared. The association between techniques for the fat changes was generally high (r = 0.70 to 0.98) and significant (p < 0.05). Assessment of agreement between DXA and the other techniques revealed discrepancies with significant slope and high association (r = -0.81 and -0.64). Whilst NAA and UWW appeared to measure similar changes, DXA underestimated small changes. 相似文献
995.
The Monte Carlo computer code MCNP (version 4A) has been used to develop a personal computer-based model of the Swansea in vivo neutron activation analysis (IVNAA) system. The model included specification of the neutron source (252Cf), collimators, reflectors and shielding. The MCNP model was 'benchmarked' against fast neutron and thermal neutron fluence data obtained experimentally from the IVNAA system. The Swansea system allows two irradiation geometries using 'short' and 'long' collimators, which provide alternative dose rates for IVNAA. The data presented here relate to the short collimator, although results of similar accuracy were obtained using the long collimator. The fast neutron fluence was measured in air at a series of depths inside the collimator. The measurements agreed with the MCNP simulation within the statistical uncertainty (5-10%) of the calculations. The thermal neutron fluence was measured and calculated inside the cuboidal water phantom. The depth of maximum thermal fluence was 3.2 cm (measured) and 3.0 cm (calculated). The width of the 50% thermal fluence level across the phantom at its mid-depth was found to be the same by both MCNP and experiment. This benchmarking exercise has given us a high degree of confidence in MCNP as a tool for the design of IVNAA systems. 相似文献
996.
Barling Julian; Kelloway E. Kevin; Iverson Roderick D. 《Canadian Metallurgical Quarterly》2003,8(1):74
A model of the attitudinal outcomes of the occurrence and severity of occupational injuries was developed and tested. The model postulates that workplace accidents result in a perceived lack of influence and a distrust of management, with the former also affecting the distrust of management. Both are hypothesized to predict job dissatisfaction. Exit (turnover intentions) and voice (perceptions of union instrumentality) are hypothesized as outcomes of job dissatisfaction. A sample of 9,908 employees was tested with the 1995 Australian Workplace Industrial Relations Survey database. Structural equation modeling provided strong support for the model with respect to accident occurrence, and the model was replicated across 8 different occupational groups. There was less support for the model with respect to accident severity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Few problems have had as interesting an intellectual trajectory through history as that of the mind and its place in nature. Before 1859, the year that Darwin and Wallace independently proposed natural selection as the basis of evolution, this issue was known as the mind/body problem with its various and sometimes ponderous solutions. But after that pivotal date, it came to be known as the problem of consciousness and its origin in evolution. Now the first thing I wish to stress this afternoon is this problem. It is easy for the average layman to understand. But paradoxically, for philosophers, psychologists, and neurophysiologists, who have been so used to a different kind of thinking, it is a difficult thing. What we have to explain is the contrast, so obvious to a child, between all the inner covert world of imaginings and memories and thoughts and the external public world around us. The theory of evolution beautifully explains the anatomy of species, but how out of mere matter, mere molecules, mutations, anatomies, can you get this rich inner experience that is always accompanying us during the day and in our dreams at night? That is the problem we will consider in this symposium. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
In planning the McMaster University Brain and Behaviour Research Programme's 1983 Bauer lecture, it was deemed that a topic in the area of cognitive neuroscience might be suitable, preferably one of a general nature that would be of interest to several disciplines. Consciousness, one of the most perplexing of human issues, requires that we question how the living material of the human brain results in the subjective awareness humankind experiences. Julian Jaynes was asked to present the lecture, which was entitled "Consciousness and the voices of the mind" (see record 2007-08986-001). In this article, Jaynes responds to comments on his lecture by Daniel Dennett (see record 2007-09336-002), Jonathan Miller (see record 2007-09336-003), and George Ojemann (see record 2007-09336-004). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
To assess whether work experiences and stressors are associated with wife abuse (WA), 18 maritally satisfied, 12 dissatisfied/nonabusive, and 18 dissatisfied/abusive husbands (mean age 35.3 yrs) completed work involvement, organizational commitment, job satisfaction, and work stress questionnaires (yielding occurrence, positive, and negative impact indices). Multiple analysis of variance (MANOVA) revealed that overall work experiences were significantly associated with WA. Univariate analyses of variance (ANOVAs) showed that only the occurrence of stressful work events and their negative impact were significantly associated with WA. Conceptual and methodological implications concerning the association between work stress and WA are suggested, and the needs for a true causal analyses on the effects of work stressors on WA and for a focus on personality and situational variables enhancing or reducing the likelihood of spouse abuse are emphasized. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Julian K. Benz Laura J. Carroll Jill K. Wright Richard N. Wright Thomas M. Lillo 《Metallurgical and Materials Transactions A》2014,45(7):3010-3022
Creep of Alloy 617, a solid solution Ni-Cr-Mo alloy, was studied in the temperature range of 1023 K to 1273 K (750 °C to 1000 °C). Typical power-law creep behavior with a stress exponent of approximately 5 is observed at temperatures from 1073 K to 1273 K (800 °C to 1000 °C). Creep at 1023 K (750 °C), however, exhibits threshold stress behavior coinciding with the temperature at which a low volume fraction of ordered coherent γ′ precipitates forms. The threshold stress is determined experimentally to be around 70 MPa at 1023 K (750 °C) and is verified to be near zero at 1173 K (900 °C)—temperatures directly correlating to the formation and dissolution of γ′ precipitates, respectively. The γ′ precipitates provide an obstacle to continued dislocation motion and result in the presence of a threshold stress. TEM analysis of specimens crept at 1023 K (750 °C) to various strains, and modeling of stresses necessary for γ′ precipitate dislocation bypass, suggests that the climb of dislocations around the γ′ precipitates is the controlling factor for continued deformation at the end of primary creep and into the tertiary creep regime. As creep deformation proceeds at an applied stress of 121 MPa and the precipitates coarsen, the stress required for Orowan bowing is reached and this mechanism becomes active. At the minimum creep rate at an applied stress of 145 MPa, the finer precipitate size results in higher Orowan bowing stresses and the creep deformation is dominated by the climb of dislocations around the γ′ precipitates. 相似文献