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151.
152.
Chemtob Claude M.; Novaco Raymond W.; Hamada Roger S.; Gross Douglas M. 《Canadian Metallurgical Quarterly》1997,65(1):184
With a randomized group design, a 12-session anger treatment was evaluated with severely angry Vietnam War veterans suffering combat-related posttraumatic stress disorder (PTSD). Eight participants in anger treatment and 7 in a routine clinical care control condition completed multiple measures of anger control, anger reaction, and anger disposition, as well as measures of anxiety, depression, and PTSD at pre- and posttreatment. Controlling for pretreatment scores, significant effects were found on anger reaction and anger control measures but not on anger disposition or physiological measures. Eighteen-month follow-up (for both completers and dropouts) supported the posttreatment anger control findings. The challenges of treatment research with this refractory population are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
153.
Halpin S.M. Grigsby L.L. Gross C.A. Nelms R.M. 《Power Delivery, IEEE Transactions on》1994,9(3):1332-1338
The results of an improved method for fault calculations in unbalanced multi-phase power distribution systems containing nonutility generators and large induction motor loads are presented in this paper. The method utilizes a combined time- and frequency-domain analysis approach to produce results that are superior to those obtained in “classical” fault analysis without the large increase in computer time with complete time-domain solutions. Sources and loads can be represented by either classical frequency-domain models or detailed differential equation models. The potentially unbalanced power distribution system is represented by an admittance matrix formed using a linear graph-based application of AC circuit theory. The time-domain differential equation source and load models are interfaced with the frequency-domain distribution system model using time series analyses to estimate equivalent voltage and current phasors from discrete data sets 相似文献
154.
Neurons, by virtue of intrinsic electrophysiological mechanisms, represent transducers that report the dynamics of cell death, receptor-ligand interactions, alterations in metabolism, and generic membrane perforation processes. In cell culture, mammalian neurons form fault-tolerant, spontaneously active systems with great sensitivity to their chemical environment and generate response profiles that are often concentration- and substance-specific. Changes in action potential patterns are usually detected before morphological changes and cell damage occur, which provides sensitivity and reversibility. Such biological systems can be used to screen rapidly for novel pharmacological substances, toxic agents, and for the detection of certain odorants. Existing simple culture preparations can already be employed effectively for the detection of chemical compounds. So far, three strategies have been investigated in pilot experiments: (1) Substance-dependent major changes in spontaneous native activity patterns. All synaptically active agents (e.g. glutamate, strychnine, N-methyl D-aspartic acid) as well as metabolic poisons generate such changes. (2) Substance-dependent changes in network oscillations via disinhibition. The regularized, oscillatory activity is altered by synaptically and metabolically active substances, ion channel blockers, and toxins. (3) Detection of paroxysmal responses indicating major, pathological membrane currents in large subpopulation of cells. We have explored these three strategies via 64 channel array recordings using spontaneously active murine spinal cord cultures. The glycine receptor blocker strychnine reliably generated increased multichannel bursting at 5-20 nM and regular, coordinated bursting above 5 microM. During biculline-induced network oscillations many compounds alter oscillation frequencies or terminate activity in a substance-specific manner. Finally, the gp120 protein of the AIDS virus (at 1 microgram/ml) produces massive, unique paroxysmal discharges that may last as long as 2 min. These results indicate that cultured neuronal networks are practical systems that can be used for the detection and identification of a great variety of chemical substances. The concept of dynamic fingerprinting to identify specific compounds is discussed. 相似文献
155.
This study analyzes the severity of coronary artery disease in terms of the severity of renal artery disease in 609 patients undergoing coronary and renal angiography. The presence of renal artery disease of any severity is strongly suggestive of advanced coronary artery disease. 相似文献
156.
J Klosterk?tter F Schultze-Lutter G Gross G Huber EM Steinmeyer 《Canadian Metallurgical Quarterly》1997,95(5):396-404
Magnetization transfer through dipole-dipole interactions (nuclear Overhauser effects, NOEs) between water protons and the protons lining two small hydrophobic cavities in hen egg-white lysozyme demonstrates the presence of water molecules with occupancies of approximately 10-50%. Similarly, NOEs were observed between the cavity protons and the protons of hydrogen, methane, ethylene or cyclopropane applied at 1-200 bar pressure. These gases can thus be used as general NMR indicators of empty or partially hydrated hydrophobic cavities in proteins. All gases reside in the cavities for longer than 1 ns in marked contrast to common belief that gas diffusion in proteins is not much slower than in water. Binding to otherwise empty cavities may be a major aspect of the anesthetic effect of small organic gas molecules. 相似文献
157.
PA Gross 《Canadian Metallurgical Quarterly》1997,11(4):803-812
Practice guidelines can help clinicians and microbiologists improve the quality and efficiency of health care. Numerous areas are in need of guideline development and development of quality improvement programs. These areas include antibiotic control, duration of antibiotic administration, use of narrowest spectrum, least toxic, lowest cost-effective antibiotic, use of rapid diagnostic tests, management of outpatient intravenous antibiotics, antibiotic prophylaxis for surgery, switching from intravenous to oral antibiotics, antibiotic selection for special situations, diagnosis of Lyme disease, and several other topics. IDSA, SHEA, CDC, NIH, and other organizations are cooperating to develop these guidelines. 相似文献
158.
159.
In Experiment 1, 32 5- to 6-year-old boys and girls participated in a unique event and were interviewed about that event 1 day later. Half of the children were asked to draw what happened during the event and half were asked to tell what happened. In both conditions, only children's verbal behavior was scored. Children in the draw group were as accurate and reported more information than children in the tell group, especially in response to direct questions. In Experiment 2, 32 5- to 6-year-olds and 32 3- to 4-year-olds participated in the same event used in Experiment 1 and were interviewed 1 month later. The 5- to 6-year-olds in the draw group reported more information than the 5- to 6-year-olds in the tell group after the 1-month delay. Drawing did not, however, increase the amount of information reported by 3- to 4-year-olds. These findings have important theoretical implications for memory development and important practical implications for children's eyewitness testimony. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
160.
McCown R. Gross F.B. Calle C.I. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2005,12(4):821-826
NASA has great interest in testing the electrostatic charging of various materials due to the saltation process near the surface of Mars. As wind blows over the Martian regolith, particles are picked up, travel over a distance, and then fall back to the surface. These moving particles collide with each other and with any other materials present giving rise to a triboelectric charge transfer. Variables involved in this charge transfer include the number of particles, the frequency of collisions, and the particle velocities. It is necessary to know the extent of charging of man-made materials in this process in order to better plan future Mars missions. Two different methods for creating frictional charging between the regolith simulant and the materials in question are described. The first method utilizes a deflection board apparatus. The second uses a shaker box apparatus. The benefits and drawbacks of each experimental approach are listed. Some experimental data obtained through each method is provided but further study is required to fully characterize these charging processes. 相似文献