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51.
P Sellier B Eisenmann P Charon JL Guermonprez P Maurice 《Canadian Metallurgical Quarterly》1976,15(3):477-480
In this study, the effects of forearm static exercise were determined on local blood flow and oxygen consumption in 15 normal individuals (NL) and their responses were compared with ten patients in congestive heart failure (CHF). Forearm blood flow was determined by a plethysmographic technique before and during 15% of maximum voluntary contraction of the forearm. Regional arterial and venous oxygen contents were sampled and forearm oxygen consumption calculated by the Fick principle. At rest, forearm blood flow was less in patients with heart failure than in normal individuals; however, this was compensated for by an increased oxygen extraction, thus maintaining forearm oxygen consumption at a normal level. In contrast, during static exercise, forearm blood flow failed to rise normally with heart failure (NL 9.31; CHF 4.35 ml/min-100 ml, P less than 0.001) and the increased oxygen extraction was not sufficient to maintain a normal forearm oxygen consumption (NL .82; CHF .44 ml/min-100 ml, P less than 0.01). Therefore, patients with congestive heart failure demonstrate regional circulatory and metabolic abnormalities during static exercise that are comparable to those present during dynamic exercise. Because of a limited ability of their skeletal muscle resistance vessels to respond to dilator stimuli, they have an attenuation of their exercise hyperemia which leads to an earlier shift to anaerobic metabolism. 相似文献
52.
Oxide layers grown on the surface provide an effective way of protecting metallic materials against corrosion for sustainable use in a broad range of applications. However, the growth of cavities at the metal/oxide interface weakens the adherence of the protective layer and can promote its spallation under service conditions, as observed for alumina layers formed by selective oxidation of aluminide intermetallic alloys used in high-temperature applications. Here we show that direct atomic-scale observations of the interface between an ultrathin protective oxide layer (alumina) grown on an intermetallic titanium aluminide substrate (TiAl) can be performed with techniques sensitive to the topmost atomic layers at the surface. Nanocavities resulting from the self-assembling of atomic vacancies injected at the interface by the growth mechanism of the protective oxide are observed for the first time, bringing new insight into the understanding of the fate of injected cavities in oxidation processes. 相似文献
53.
A read-modify-write register for a set of functions F provides an operation that atomically (1) returns the variables current value v, and (2) replaces that value with f(v), where f is a function in F.A read-modify-write network is a distributed data structure that implements a concurrent, lock-free, low-contention read-modify-write register. For example, counting networks ([3]) are a family of read-modify-write networks that support atomic increments and decrements.We consider the problem of constructing read-modify-write networks for particular sets of functions. Of particular interest are the read-modify-write networks fetch&add, which add to the value an arbitrary number, and fetch&mul, which multiply the value by an arbitrary number.We identify a simple algebraic property of the function set F that requires any distributed read-modify-write implementation for F to have high latency. Any such network has sequential executions in which each token traverses a number of switching elements essentially linear in the number of processes. By contrast, there exist counting networks ([9, 18]) in which tokens traverse a logarithmic number of switches.We provide a matching upper bound for a large class of read-modify-write networks including fetch&add, fetch&mul, and related networks of interest.Received: 15 October 2002, Accepted: 15 May 2003, Published online: 6 February 2004Panagiota Fatourou: Partially supported by funds from the Program E.
.E.A.E.K.II of the Greek Ministry of Education. Part of the work of theauthor was performed while at the Max-Planck Institut für Informatik,Saarbrücken, Germany, while at the Department of Computer Science,University of Toronto, Canada, and while visiting the Departmentof Computer Science, Brown University, Providence, USA.Maurice Herlihy: Partially supported by NSF grant 9912401.A preliminary version of this work appears in the Proceedings of the 15th International Symposium on DIStributed Computing, pp. 330-341, Lisbon, Portugal, October 2001. This work also appears as a brief announcement in the Proceedings of the 20th Annual ACM Symposium on Principles of Distributed Computing, Newport, Rhode Island, August 2001. 相似文献
54.
"A sample of 423 psychotic patients from five veterans hospitals was observed and rated on behavior in the interview and on the ward. The intercorrelations between 55 of the rating scales were subjected to a multiple group factor analysis. The 11 oblique first order factors were interpreted." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Larry J. Darlage Harry N. Finkbone Samuel J. King Jitendra Ghosal Maurice E. Bailey 《Fuel》1978,57(8):479-484
A series of 34 nitrogen-containing compounds with a wide range of basicities was examined under differential nonaqueous potentiometric conditions in acetophenone and nitrobenzene. These compounds could be resolved into five classes based on pKaand half-neutralization-potential (HNP) values. Asphaltenes isolated from the vacuum still overhead (VSO) and vacuum still bottoms (VSB) fractions of the H-coal process were titrated under similar conditions. The titration results of both asphaltenes indicated the presence of two classes of nitrogen-containing compounds, a titratable class of the pyridine-ring or aniline type and a nontitratable class. 相似文献
56.
There is growing evidence that the p-wave superconductivity of Sr2RuO4 occurs primarily in the planar -band. Thus the minimum model for both cuprates and ruthenates is a single active band with onsite Coulomb interactions. Recent renormalization group analysis shows that such a model can show singlet d-wave or triplet p-wave pairing. The energy of the van Hove singularity in the band and the shape of the Fermi surface are the decisive factors at weak to moderate interaction strengths. 相似文献
57.
Brennetot R Lacour JL Vors E Rivoallan A Vailhen D Maurice S 《Applied spectroscopy》2003,57(7):744-752
A project called MALIS (Mars Analysis by Laser-Induced breakdown Spectroscopy) is under progress to perform in situ analysis of Mars soils and rocks. This paper reports on the behavior of plasma in Martian conditions, i.e., in a CO2 atmosphere at pressures between 5 and 12 mbar. Plasma expansion and lifetime have been studied in order to compare plasma evolution under standard conditions (air at atmospheric pressure) and in a Mars atmosphere. We have shown that the Mars environment favors plasma expansion and lifetime. The second part of the study concerns optimization of the emission signal from the plasma. An original approach has been chosen, as we used a Doehlert design for the first time in laser-induced breakdown spectroscopy (LIBS). The best conditions obtained are for a laser wavelength of 1064 nm with the maximum energy available due to space limitations, which is 40 mJ at 15 Hz. The other factors studied are delay, angle of incidence, and CO2 pressure. We have shown that these factors do not have the same influence depending on which spectroscopic line is used, i.e., the atomic line or the ionic line. 相似文献
58.
Maurice Fickelson 《Materials and Structures》2001,34(7):447-447
RILEM Bulletin
Prof. Dr. Geert De Schutter, 2001 Robert L'hermite Medallist 相似文献59.
Blondel WC Didelon J Maurice G Carteaux JP Wang X Stoltz JF 《IEEE transactions on bio-medical engineering》2001,48(4):442-451
In order to investigate the three-dimensional (3-D) mechanical properties of blood vessels, a new experimental device is described allowing in vitro static and dynamic measurements on segments of arteries with high technical performances. Static tests are applied to sheep common carotid arteries. Considering a thick-walled cylindrical model of orthotropic material under large deformations, a classical 3-D approach based on strain energy density is used to calculate the resulting mechanical behavior law in radial and circumferencial directions and stresses distribution throughout the wall thickness. Results are presented with reference to unloaded and zero-stress initial state thanks to simple measurements of inner and outer circumferences. A particular ratio relating the two main stresses (circumferential and longitudinal) is calculated that put into the forth the progressive modifications in the direction of the predominant stress in the wall and the specific radial location where these changes occur. The authors observe that this point location is a function of the test conditions of the specimen, i.e., stretching length and level of pressure 相似文献
60.
Ofer Arieli Marc Denecker Maurice Bruynooghe 《Annals of Mathematics and Artificial Intelligence》2007,50(3-4):389-415
In many scenarios, a database instance violates a given set of integrity constraints. In such cases, it is often required
to repair the database, that is, to restore its consistency. A primary motif behind the repairing approaches is the principle of minimal change, which is the aspiration to keep the recovered data as faithful as possible to the original (inconsistent) database. In this
paper, we represent this qualitative principle quantitatively, in terms of distance functions and some underlying metrics,
and so introduce a general framework for repairing inconsistent databases by distance-based considerations. The uniform way
of representing repairs and their semantics clarifies the essence behind several approaches to consistency restoration in
database systems, helps to compare the underlying formalisms, and relates them to existing methods of defining belief revision
operators, merging data sets, and integrating information systems.
相似文献