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81.
Naveh-Benjamin Moshe; Hussain Zahra; Guez Jonathan; Bar-On Maoz 《Canadian Metallurgical Quarterly》2003,29(5):826
This study further tested an associative-deficit hypothesis (ADH; M. Naveh-Benjamin, 2000), which attributes a substantial part of older adults' deficient episodic memory performance to their difficulty in merging unrelated attributes-units of an episode into a cohesive unit. First, the results of 2 experiments replicate those observed by M. Naveh-Benjamin (2000) showing that older adults are particularly deficient in memory tests requiring associations. Second, the results extend the type of stimuli (pictures) under which older adults show this associative deficit. Third, the results support an ADH in that older adults show less of an associative deficit when the components of the episodes used are already connected in memory, thereby facilitating their encoding and retrieval. Finally, a group of younger adults who encoded the information under divided-attention conditions did not show this associative deficit. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
In this work, we compare the performance of flow-reversal, internal-recirculation and loop reactors. In the absence of analytical results we use asymptotic, approximate and simulated solutions and present some experimental results. As criteria for comparison we use the maximal temperature achieved and the robustness of solution.Experiments and simulations of ethylene oxidation in the flow-reversal and internal-recirculation reactor, showed that the technically simpler inner-outer internal-recycle reactor may operate better at low flow rates than that with flow reversal, but the conclusion is reversed at high flow rates. Using approximate solutions, we show the dependence of the maximal temperature on the inner-outer heat-transfer coefficient.Loop reactor can generate rotating pulse solution: we simulate such solutions for two asymptotic cases where the ratio of switching velocity (i.e., unit length/switching time) to pattern velocity is either around unity or very large. We compare them with solutions of 4-8 units reactors. The slow-switching regimes require a delicate control. The fast-switching solution is robust but its peak temperature depends on the kinetic parameters and reactor length, compared with that of the flow-reversal reactor where it depends mainly on bed conductivity. 相似文献
83.
In this paper the exact vibration frequencies of generally laminated beams are found using a new method, including the effect of rotary inertia and shear deformations. The effect of shear in laminated beams is more significant than in homogenous beams, due to the fact that the ratio of extensional stiffness to the transverse shear stiffness is high. The exact dynamic stiffness matrix is derived, and then any set of boundary conditions including elastic connections, and assembly of members, can be solved as in the classical direct stiffness method for framed structures. The natural frequencies of vibration of a structure are those values of frequency that cause the dynamic stiffness matrix to become singular, and one can find as many frequencies as needed from the same matrix. In the paper several examples are given, and compared with results from the literature. 相似文献
84.
Moshe Dayan 《Journal of Superconductivity and Novel Magnetism》2014,27(9):1973-1981
This work is based on the double correlated linear aggregations of holes in checkerboard geometry. It is proved that the pairing function symmetry is ?d x2 ? y2, as been observed experimentally. It is also shown that there is a “superconductive spin gap” for the observation of the magnetic incommensurate modulation peaks, in agreement with the experiment. In addition, the unperturbed Hamiltonian and its related propagator are reanalyzed and modified. 相似文献
85.
Elder John P.; Ayala Guadalupe X.; Campbell Nadia R.; Slymen Donald; Lopez-Madurga Eva T.; Engelberg Moshe; Baquero Barbara 《Canadian Metallurgical Quarterly》2005,24(1):49
Participants (N = 357) were randomly assigned to 1 of 3 conditions: lay health advisor (promotora) plus tailored print materials, tailored print materials only (tailored), or off-the-shelf print materials (control). The primary outcomes were calories from fat and daily grams of fiber. Secondary outcomes included total energy intake, total and saturated fat intake, and total carbohydrates. Adjusted for baseline values, calories from fat were 29%, 30%, and 30% for the promotora, tailored, and control conditions, respectively, and grams of fiber consumed were 16 g, 17 g, and 16 g. Significant Condition X Time interactions were not observed between baseline and 12-weeks postintervention. The LHA condition achieved significantly lower levels of energy intake, total fat and saturated fat, and total carbohydrates. The relative superiority of the promotora condition may derive from the personal touch achieved in the face-to-face interactions or from the women's use of print materials under the promotora's guidance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Dharmaraj Veeramani David M. Upton Moshe M. Barash 《International Journal of Flexible Manufacturing Systems》1992,4(3-4):237-265
The problem of cutting tool management has been brought to the forefront with the emergence of computer-integrated manufacturing (CIM) and, in particular, flexible manufacturing systems (FMSs). The financial and operational ramifications of effective tool management has spurred considerable research in this area during the past decade and many researchers are proposing sound solutions to various facets of this broad-ranging and difficult problem. This paper identifies critical areas of research for the development of tool management systems in CIM. To develop a framework for this, the paper examines and categorizes work in academia and in industry on the management of cutting-tools in CIM and describes some key implementations, particularly in the metal-cutting industry. The solution of manufacturing problems generally demands an eclectic approach, and for this reason, we have tried to taxonomize, describe, and critique the various research thrusts in an attempt to provide a synthesis of use in more unified approaches. 相似文献
87.
Moshe Dayan 《Journal of Superconductivity and Novel Magnetism》2006,19(6):477-484
We reexamine the Nambu–Gorkov perturbation theory of superconductivity. We suggest that any field perturbation theory of superconductivity
should be based on the Bogoliubov–Valatin (BV) quasi-particles. We show that two such different fields (and two additional
analogous fields) may be constructed on the basis of this suggestion. The Nambu field is only one of them. For the field that
is different than Nambu’s, the coherence field, the interaction is given by means of two interaction vertices that are based
on the Pauli matrices τ1 and τ3. Consequently, the Hartree integral for the off-diagonal pairing self-energy may be finite, and in some cases large. We interpret
the results in terms of conventional superconductivity and also discuss briefly the possible implications to HTSC. 相似文献
88.
Naveh-Benjamin Moshe; Guez Jonathan; Kilb Angela; Reedy Sarah 《Canadian Metallurgical Quarterly》2004,19(3):541
Previous studies have established an associative deficit hypothesis (Naveh-Benjamin, 2000), which attributes part of older adults' deficient episodic memory performance to their difficulty in creating cohesive episodes. In this article, the authors further evaluate this hypothesis, using ecologically relevant materials. Young and old participants studied name-face pairs and were then tested on their recognition memory for the names, faces, and the name-face pairs. The results extend the conditions under which older adults exhibit an associative deficit. They also show that reduced attentional resources are not the sole mediator of this deficit. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
Michael Ryvkin Moshe B. Fuchs Fabian Lipperman Leonid Kucherov 《International Journal of Fracture》2004,128(1-4):215-221
The periodic structure of some natural and especially man-made materials can be manifested not only on an atomic but also on a larger scale. Investigation of mechanical properties of these materials usually hinges on well-developed homogenization methods. On the other hand, these methods are not suitable for fracture analysis where the knowledge of the local stress-strain fields near a flaw (a crack) is required. The result is obtained by the use of the representative cell method based on the discrete Fourier transform. This method enables one to determine the exact stress distribution in a periodic structure subjected to arbitrary loading. Direct application of the method is impossible since the crack violates the translational symmetry defined by the material microstructure. This obstacle is overcome by application of the fictitious loading to the uncracked body at the line where the crack is to be located. The amplitude of the loading is adjusted in order to fulfill the boundary conditions imposed on the crack faces. The compatibility equation for deriving this amplitude is obtained by the use of the corresponding Green function, which is found in a closed form. Fracture problems for the two types of materials with a periodic microstructure are considered. The first one is a composite material consisting of dissimilar isotropic elastic layers arranged periodically. The second periodic microstructure is a 2D infinite beam lattice modeling a cellular material. The analysis of the failure process in the latter case shows that in contrast to the case of homogeneous material, the crack propagation path is not defined by the condition of zero Mode II stress intensity factor. 相似文献
90.
Describes an incident in which a Bedouin 8th grader in Israel killed a classmate. The author describes how he applied S. Sue and N. Zane's (see record 1987-16319-001) interpretations of cross-cultural therapy research, which emphasize credibility and giving, to this situation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献