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91.
Person–organization fit (P–O fit) research and practice have been hindered on account of the difficulty of operationalizing the richness, complexity and subjectivity of the P–O fit phenomenon. P–O fit for technology professionals is further complicated by the rapidly changing demands the IT profession places on its constituents to continually engage in training and development. A human capital perspective is adopted as a lens through which to view the IT professional's P–O fit, and Social Cognitive Theory is proposed as a framework within which to incorporate the principles of Concourse Theory, which is the guiding philosophy of Q‐Methodology and Q‐sorts. The Q‐methodology was used as a means to operationalize the IT professional's P–O fit with respect to IT training and development. Analysis revealed five distinct P–O fit types of perspectives that explained 35% of the population variance. Post‐hoc analysis of the five types revealed that they are interpretable through the lens of the human capital perspective. The results show promise for continued research on the subject, as well as implications for both researchers and practitioners. 相似文献
92.
Nieuwejaar N. Kotz D. Purakayastha A. Sclatter Ellis C. Best M.L. 《Parallel and Distributed Systems, IEEE Transactions on》1996,7(10):1075-1089
Phenomenal improvements in the computational performance of multiprocessors have not been matched by comparable gains in I/O system performance. This imbalance has resulted in I/O becoming a significant bottleneck for many scientific applications. One key to overcoming this bottleneck is improving the performance of multiprocessor file systems. The design of a high-performance multiprocessor file system requires a comprehensive understanding of the expected workload. Unfortunately, until recently, no general workload studies of multiprocessor file systems have been conducted. The goal of the CHARISMA project was to remedy this problem by characterizing the behavior of several production workloads, on different machines, at the level of individual reads and writes. The first set of results from the CHARISMA project describe the workloads observed on an Intel iPSC/860 and a Thinking Machines CM-5. This paper is intended to compare and contrast these two workloads for an understanding of their essential similarities and differences, isolating common trends and platform-dependent variances. Using this comparison, we are able to gain more insight into the general principles that should guide multiprocessor file-system design 相似文献
93.
Ellis SR 《Presence (Cambridge, Mass.)》1996,5(2):247-259
An operator's sense of remote presence during teleoperation or use of virtual environment interfaces is analyzed as to what characteristics it should have to qualify it as an explanatory scientific construct. But the implicit goal of designing virtual environment interfaces to maximize presence is itself questioned in a second section in which examples of human-machine interfaces beneficially designed to avoid a strong sense of egocentric presence are cited. In conclusion, it is argued that the design of a teleoperation or virtual environment system should generally focus on the efficient communication of causal interaction. In this view the sense of presence, that is of actually being at the simulated or remote workplace, is an epiphenomena of secondary importance for design. 相似文献
94.
95.
A gas chromatographic spectrometric assay was used to measure tissue and released acetylcholine and choline in diaphragm preparations of rats previously injected with botulinum toxin type A. Botulinum intoxication was found not to alter the acetylcholine content of rat diaphragms in vivo or in fully paralyzed muscles in vitro. This result provides direct support for the hypothesis that botulinum toxin blocks transmitter release without affecting acetylcholine synthesis. However, in diaphragm preparations in vitro, this toxin was found to inhibit not only the evoked release of acetylcholine but also the spontaneous "leakage" of acetylcholine that is measured at rest. Additional experiments were performed to characterize this action of the toxin. The magnitude of the decline in resting acetylcholine output appears to be too large to be accounted for solely by the known effect of botulinum toxin to reduce the frequency of miniature endplate potentials. The mechanism of this action of botulinum toxin remains an enigma. 相似文献
96.
Ion-pairs in proteins 总被引:2,自引:0,他引:2
A "working definition" for an ion-pair has been derived based upon analysis of the distance distributions for like- and oppositely charged groups in 38 proteins. Ion-pairs defined according to this criterion (less than or equal to 4 A between charged groups) have been analysed in respect of: (1) the frequencies of different pair types; (2) the residue separations and secondary structural locations of the residues involved; (3) the flexibility of the side-chains involved; (4) their conformation; (5) their environment (accessibility to solvent and proximity to active site or ligand binding regions); and (6) their conservation in related proteins. The results obtained indicate that on average one-third of the charged residues in a protein are involved in ion-pairs and 76% of these are concerned with stabilizing the tertiary (rather than the secondary) structure. Only 17% of ion-pairs are buried, and conservation of the interactions is generally low unless the residues involved have more specific functions to perform. In the light of the results obtained, the role of ion pairs in globular proteins is discussed. 相似文献
97.
From time to time the literature mentions curious effects on the chemical reactivity of metals due to inert gas ion bombardment: reactivity in corrosive environments is variously said to be inhibited or enhanced. Although there is no obvious explanation for such effects, some possible mechanisms have been suggested. We have carried out a few simple experiments designed to demonstrate that reactivity effects really do exist and to test such mechanisms as have been proposed. The results are qualitative because a glow discharge was used to implant the rare gas ions.Evaporated films of aluminium and nickel become amorphous after bombardment with xenon ions and the films resisted gaseous and liquid corrosion. On the other hand, aluminium foil bombarded with xenon ions in a Penning pump arrangement was attacked more heavily than unbombarded aluminium. We attribute passivation to the known lack of reactivity of amorphous metals. Glassy materials appear to lack the normal routes of attack between their subsurface regions and the attacking medium. On the other hand, when a metal surface is heavily ion bombarded the surface is probably damaged to such an extent that the attacking medium gains physical access to the interior and corrosion proceeds rapidly. 相似文献
98.
Abstract This study investigates the case-based learning experience of 133 undergraduate veterinarian science students. Using qualitative methodologies from relational Student Learning Research, variation in the quality of the learning experience was identified, ranging from coherent, deep, quality experiences of the cases, to experiences that separated significant aspects, such as the online case histories, laboratory test results, and annotated images emphasizing symptoms, from the meaning of the experience. A key outcome of this study was that a significant percentage of the students surveyed adopted a poor approach to learning with online resources in a blended experience even when their overall learning experience was related to cohesive conceptions of veterinary science, and that the difference was even more marked for less successful students. The outcomes from the study suggest that many students are unsure of how to approach the use of online resources in ways that are likely to maximise benefits for learning in blended experiences, and that the benefits from case-based learning such as authenticity and active learning can be threatened if issues closely associated with qualitative variation arising from incoherence in the experience are not addressed. 相似文献
99.
P Ellis 《Canadian Metallurgical Quarterly》1995,26(8):56-58
A study surveyed RNs and LPNs who had been involved in the Board of Nursing's discipline process for chemical dependency. The association between the type of disciplinary action taken and the perceived benefits to recovery are rated. 相似文献
100.