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121.
Recycling water is not new. Yet, there are many examples from around the world of recycled water projects that have failed because of public opposition. This article reviews the literature investigating factors associated with public acceptance of recycled water, as well as publicly accessible reports and case studies, which have developed or tested approaches to increase public acceptance. The article concludes by summarizing the state of knowledge in this area, and advancing key research questions relating to public acceptance of recycled water that urgently need to be investigated. 相似文献
122.
A two-node model of a room has been implemented in a computer program, WinSim, developed for evaluation of thermal performance of windows in new buildings and in case of retrofitting. The program calculates the annual heating demand and the number of hours with indoor temperatures higher than a user defined limit. WinSim is characterised by the limited amount of required input data. Guidelines for calculation of the effective thermal capacity of the room are given, and results obtained with WinSim have been compared to results from an advanced building simulation program. Good agreement has been found between the two programs with respect to calculated annual heating demand and energy savings due to window exchange, and also the calculated number of hours with overtemperature is similar. Based on the limited examples used for the comparison, it can be concluded that WinSim is well suited for a quick but realistic evaluation of thermal performance of windows. 相似文献
123.
Rotary actuators are electromagnetic devices developing mechanical torque with limited rotary motion. Because of their simplicity and low cost they are finding more and more applications, especially in the automotive field. This paper describes a novel homopolar rotary actuator with a ring-type radially magnetized multipolar permanent magnet featuring a high force density “transverse flux” configuration which performs a spring action by developing electromagnetic torques with limited angular movement. Because of the magnetically complicated and nonsymmetrical rotary actuator configuration, the analysis of this actuator is based on 3-D finite element software. The analysis, which is well supported by test results, shows that symmetrical magnetic forces in both directions of rotation were achieved with a stable equilibrium position, satisfying all design requirements to enhance the basic hydraulic power steering system of passenger vehicles 相似文献
124.
Di Bias A. Dahle D.M. Diekhans M. Grate L. Hirschberg J. Karplus K. Keller H. Kendrick M. Mesa-Martinez F.J. Pease D. Rice E. Schultz A. Speck D. Hughey R. 《Parallel and Distributed Systems, IEEE Transactions on》2005,16(1):80-92
The architectural landscape of high-performance computing stretches from superscalar uniprocessor to explicitly parallel systems, to dedicated hardware implementations of algorithms. Single-purpose hardware can achieve the highest performance and uniprocessors can be the most programmable. Between these extremes, programmable and reconfigurable architectures provide a wide range of choice in flexibility, programmability, computational density, and performance. The UCSC Kestrel parallel processor strives to attain single-purpose performance while maintaining user programmability. Kestrel is a single-instruction stream, multiple-data stream (SIMD) parallel processor with a 512-element linear array of 8-bit processing elements. The system design focuses on efficient high-throughput DNA and protein sequence analysis, but its programmability enables high performance on computational chemistry, image processing, machine learning, and other applications. The Kestrel system has had unexpected longevity in its utility due to a careful design and analysis process. Experience with the system leads to the conclusion that programmable SIMD architectures can excel in both programmability and performance. This work presents the architecture, implementation, applications, and observations of the Kestrel project at the University of California at Santa Cruz. 相似文献
125.
S.-L. Drechsler H. Rosner S.V. Shulga G. Fuchs H. von Lips J. Freudenberger M.S. Golden M. Knupfer K.-H. Müller L. Schultz J. Fink G. Kaindl H. Eschrig K. Koepernik 《Journal of Low Temperature Physics》1999,117(5-6):1617-1621
The electronic structure of tetragonal (RC(N))m(TB)2, m=1–3, compounds, with R= Y,Lu,La, T=Ni,Pt is studied. Total and partial densities of states N(E) are calculated and compared with orbital resolved x-ray absorption data. Special attention is paid to the structure of N(E) near the Fermi-level and its consequences for thermodynamic properties in the superconducting and the normal states. A medium el-ph coupling constant 0.5 1.2 is found. There is no simple correlation between N(0) and T
c
. The analysis of the upper critical field reveals the presence of at least two groups of electrons with quite different Fermi velocities v
F
in accord with dHvA data, and with calculated distributions of v
F
around the Fermi surface 相似文献
126.
Redlich A Perka C Schultz O Spitzer R Häupl T Burmester GR Sittinger M 《Journal of materials science. Materials in medicine》1999,10(12):767-772
Large bone defects caused by severe trauma, infection or tumor resection are still a major challenge for orthopaedic surgery. The key concept for successful bone regeneration consists of combining the osteoinductive effect of osteogenic cells with a suitable carrier structure to promote osteoblastic differentiation and optimal matrix production. Therefore, periosteal cells cultured in polyglycolic-polylactid acid (PGLA) fleeces were investigated for their osteogenic differentiation and used to repair critical size bone defects in a rabbit model. Periosteal cells were isolated from New Zealand White rabbits and expanded in vitro. Osteogenic differentiation was investigated by analysis of alkaline phosphatase and osteocalcin production in vitro depending on culture conditions and passage number. Cells were seeded into PGLA fleeces. After further cultivation, tissue constructs were examined histologically and by immunohistochemistry for cell distribution and osteogenic differentiation. These constructs of defined size were used to repair critical size calvarial defects (group I) in rabbits compared to a defect repair with polymers only (group II) or to untreated defects (group III). Bone healing was evaluated after 4 weeks by radiodensitometry and a special histological scoring system. For early evaluation, radiodensitometry was not sensitive enough to detect differences in calcification. However, on histologic examination the group with cell/fleece constructs revealed intense formation of uncalcified bone. The mean defect closure of the experimental group I was 65%, compared to control groups II and III with 31% and 22%, respectively. The established methods of 3-D-cell culture and ex-vivo transplant assessment proved to be a valuable tool for quality assurance. The results demonstrate that the combination of periosteal cells and polymer fleeces is a tissue engineering approach, which may have clinical applications in various fields of reconstructive surgery. 相似文献
127.
M Dong XQ Ding DI Pinon EM Hadac RP Oda JP Landers LJ Miller 《Canadian Metallurgical Quarterly》1999,274(8):4778-4785
The molecular basis of ligand binding to receptors provides important insights for drug development. Here, we explore domains of the cholecystokinin (CCK) receptor that are critical for ligand binding, using a novel series of fluorescent photolabile probes, receptor proteolysis, and rapid high resolution separation of peptide fragments by capillary electrophoresis. Each probe incorporated the same fluorophore and a photolabile p-benzoylphenylalanine at the amino terminus of the pharmacophoric domain (residue 24 of CCK-33) of CCK analogues representing full agonist, partial agonist, and antagonist of this receptor. Each was used to label the CCK receptor expressed on Chinese hamster ovary-CCKR cells, with the labeled domain then released by cyanogen bromide cleavage. Capillary electrophoresis with laser-induced fluorescence detection achieved an on-capillary mass sensitivity of 1.6 attomoles (10(-18) mol), with an excellent signal-to-noise ratio. Each of the biologically divergent, but structurally similar probes saturably and specifically labeled the same receptor domain, consistent with conservation of "docking" determinants. This had an apparent mass of 2.9 kDa, most consistent with the first extracellular loop domain. An additional probe having its site of covalent attachment in a different region of the probe (residue 29 of CCK-33) labeled a distinct receptor fragment with differential migration on capillary electrophoresis (third extracellular loop). Identification of the specific receptor residue(s) covalently linked to the amino-terminal probes must await further fragmentation and sequence analysis. 相似文献
128.
VL Cressman EM Hicks WK Funkhouser DC Backlund BH Koller 《Canadian Metallurgical Quarterly》1998,19(6):853-866
In the cystic fibrosis (CF) patient, lung function decreases throughout life as a result of continuous cycles of infection, particularly with Pseudomonas aeruginosa and Staphylococcus aureus. The mechanism underlying the pathophysiology of the disease in humans has not been established. However, it has been suggested that abnormal, tenacious mucus, resulting perhaps from improper hydration from loss of Cl- secretion via the cystic fibrosis transmembrane conductance regulator (CFTR) protein, impairs clearance of bacteria from the CF airway and provides an environment favorable to bacterial growth. If this hypothesis is correct, it could explain the absence of respiratory disease in CFTR-deficient mice, since mice have only a single submucosal gland and display few goblet cells in their lower airways, even when exposed to bacteria. To test this hypothesis further, we induced allergic airway disease in CFTR-deficient mice. We found that induction of allergic airway disease in mice, unlike bacterial infection, results in an inflammatory response characterized by goblet cell hyperplasia, increased mucin gene expression, and increased production of mucus. However, we also found that disease progression and resolution is identical in Cftr-/- mice and control animals. Furthermore, we show that the presence of mucus in the Cftr-/- airway does not lead to chronic airway disease, even upon direct inoculation with S. aureus and P. aeruginosa. Therefore, factors in addition to the absence of high levels of mucus secretion protect the mouse from the airway disease seen in human CF patients. 相似文献
129.
Refusal to eat by the elderly, and subsequent malnutrition, occurs in both institutional and community settings. Causes include physiologic changes associated with aging, mental disorders such as dementia and depression, and medical, social, and environmental factors. Treatment approaches call for management of these causes while considering the roles that medicine, ethics, and culture play in the process. 相似文献
130.
EM Burtsev LA Zhdanova TV Riabchikova EV Batanova NB Fokina GN Gromtseva 《Canadian Metallurgical Quarterly》1998,98(9):9-11
90 infants with intrauterine growth retardation (IGR) and 100 normal infants (control group) were followed up from 5 days till 3 years of life. In IGR infants there was a more frequent combination of several neurologic syndromes, an early manifestation of motor disorders (from the very moment of birth), a delay of neuro-psychic development (during the first year of life), a tendency to development of moderate hydrocephalus by the age of 6 months. Autonomic-visceral disorders in them were mostly characterized by the symptoms of abaissement, but not of irritation. 相似文献