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1.
Neurobiological research in schizophrenia has been hampered by several confounding factors such as the heterogeneity of the illness and the paucity of biological markers. Recent progress in research methods, however, has enabled the improvement in our understanding its pathophysiology. This paper reviews recent neurochemical investigations of schizophrenia and its animal models which were conducted in Japan in the last decade. The research areas reviewed are (i) monoamine and their metabolites in body fluids, (ii) phospholipids and prostaglandins, (iii) neurochemistry in autopsy brains, (iv) immunological measures, (v) magnetic resonance spectroscopy, (vi) regional cerebral blood flows (rCBF), (vii) molecular genetics, and (viii) animal models. It is worth noting that there exist abnormalities of amino acidergic (glutamatergic and GABAergic) neurotransmission as well as monoaminergic (dopaminergic and serotonergic) one in postmortem schizophrenic brains. These abnormalities and also the findings of altered rCBF indicate the existence of disturbed neuronal circuits that contribute to the diverse symptoms of schizophrenia. Also, dysfunction of membrane phospholipids derived from studies on magnetic resonance spectroscopy may underlie negative symptoms in schizophrenia. Given that schizophrenia is considered to comprise a group of disorders with a diverse heterogeneity of etiologies, research in the next decade is expected to identify putative genes that are involved in vulnerability to schizophrenic phenotype. 相似文献
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A computer aided monitor-data processing system (CAMP-System) was developed in order to get a consistent and comprehensive database which can very precisely reflect intra-operative haemodynamic courses. The goal of the present study was to introduce a new method to scan and to gauge haemodynamic courses and to demonstrate its superiority over the traditional way of data processing based on a handwritten anaesthesia protocol. METHODS: The computerized system was applied to a study which was designed to investigate the influence of ketanserin (K) vs. urapidil (U) on haemodynamic stability during cardiac operations. Twenty male patients scheduled for myocardial revascularization received either 20 mg K or 30 mg U. Heart rate, central venous, arterial and pulmonary artery pressures were measured and on-line recorded every 20 seconds by the computer record system. In the handwritten protocol these variables were registered at eight pre-defined time points. Computerized data processing (including artifact depletion and data condensation) was compared to the results evaluated from the handwritten protocol. RESULTS: While the only significant differences in the handwritten protocol were slightly higher values of pulmonary artery pressures in group K, the computer analysis revealed a number of further differences. Higher maximum and a less stable time course of HR in group K in the pre-bypass phase and lower mean and standard deviation of MAP during cardiopulmonary bypass. CONCLUSION: Computerized data processing including automatic artifact suppression and data condensation was able to reveal differences in the course of haemodynamic variables that cannot be detected in a conventional handwritten protocol. 相似文献
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We studied the improvement of heat resistance and mechanical properties of phenolic resin modified with polymers prepared from p-hydroxyphenylmaleimide (HPMI). Homopolymers of HPMI and copolymers of HPMI with some vinyl monomers were synthesized and Mn Tg and thermal decomposition temperature of them were measured by GPC, DSC, and TG, respectively. The miscibility of homopolymer with novolac was examined by DSC. It was found that the homopolymer had good heat resistance and good miscibility with novolac. Molding compounds were prepared by hot roll-kneading the mixtures of novolac, the homopolymer, hexamethylenetetramine, and glass fiber. It was found that molded test pieces had good heat resistance. 相似文献
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The improvement of heat resistance and mechanical properties of phenolic resin was examined with the blend of novolac and copolymers prepared from p-hydroxyphenylmaleimide (HPMI) and styrene. Copolymers of HPMI and styrene with various molecular weights were synthesized. Glass transition (Tg) and thermal decomposition temperatures of the copolymers were measured by differential scanning calorimetry (DSC) and thermogravimetry (TG), respectively. The miscibility of the copolymers with novolac was examined by DSC. It was found that the copolymers had a good heat resistance and a good miscibility with novolac. Molding compounds were prepared by hot roll-kneading of mixtures that involved novolac, copolymer, hexamethylenetetramine (hexamine), and glass fiber. It was found that the test pieces prepared by transfer molding from the molding compounds showed a good heat resistance and better mechanical properties than phenolic resin modified with HPMI homopolymer. 相似文献
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T Aikoh A Tomokuni T Matsukii F Hyodoh H Ueki T Otsuki A Ueki 《Canadian Metallurgical Quarterly》1998,12(6):1355-1359
Silica and related substances such as silicate have been proven to possess "adjuvant effects". We have previously reported a finding of polyclonal human T cell activation induced by silicate as a superantigen in vitro. In this study, we observed activation-induced cell death in human lymphocytes after stimulation with chrysotile, a kind of silicate. Apoptotic cells were detected flow cytometrically using the TUNEL assay, and the maximum appearance of TUNEL positive cells occurred on day 4 of incubation. Simultaneously the manifestation of small-sized cells in the specimens increased implying apoptosis. Fas expression on lymphocytes increased to day 3 of incubation with chrysotile, and then spontaneously decreased on day 4 when remarkable apoptosis could be detected. Based on these results it is conceivable that activation-induced cell death occurred through Fas-Fas ligand interaction in lymphocytes after stimulation with silicate in a concentration with which no acute cytotoxicity has been detected. Whether and how the repeated apoptosis in definite clones of lymphocytes causes the induction of sFas synthesis need clarification. 相似文献
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Dependence of self-heating effects on operation conditions and device structures for polycrystalline silicon TFTs 总被引:1,自引:0,他引:1
Takechi K. Nakata M. Kanoh H. Otsuki S. Kaneko S. 《Electron Devices, IEEE Transactions on》2006,53(2):251-257
Self-heating, a degradation mechanism of n-channel poly-Si thin-film transistors (TFTs) due to bias stress, has been investigated. The aim of this work is to study this effect in depth to be able to propose a device structure designed to reduce it. The variation of the threshold voltage (V/sub t/) shift with the stress-pulsewidth is related to the temperature rise due to the self-heating effect that depends on the stress-pulsewidth. Electron trapping in the oxide caused by the bias stress is considered to be enhanced by the TFT temperature rise owing to the self-heating. We show that copper-film-based TFTs, which have a substrate made of an extremely thin glass layer and a copper film exhibit much reduced self-heating and thus a decrease of V/sub t/ shift caused by the bias stress. These observations are interpreted using numerical simulations to estimate the temperature rise in the poly-Si channel region due to Joule heating. 相似文献
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A. Otsuki 《Journal of Materials Science》2005,40(12):3219-3223
Energies of symmetric [001] tilt and twist small angle grain boundaries in aluminum have been examined as a function of misorientations. Boundary energies were evaluated relative to solid/liquid interfacial energies by a dihedral angle method on surface grooves. Energies of (100)s tilt boundaries with the Burgers vector of a[100] were rather smaller than those of (110)s tilt boundaries with a/2[110]. Energies of twist boundaries at θ < 4∘ were slightly larger than those of (110)s tilt boundaries. The energies were well explained as a function of misorientations by the Read-Shockley type equation. The equation also correctly described the difference in elastic energy factors between the (110)s tilt and twist boundaries. However, the term b in the equation may take a constant value independent of the Burgers vectors. 相似文献
10.
Recent progress in thermal analysis of polymers: experimental techniques and a new aspect of temperature in measurement of material properties
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Thermal analysis has been utilized in polymer research for a long time and its usefulness is widely recognized. High‐performance commercial instruments have driven significant progress in the thermal studies of polymers. On the other hand, new experimental instruments have been developed in laboratories as well. In this paper attention is paid to the latter category. The laboratory‐made instrument focused on the target material and/or phenomena provides data that are not available from other techniques. Experiments using the temperature modulation technique, which has been successfully utilized in laboratory‐made instruments, are introduced in this paper. The temperature modulation technique reveals a new aspect of temperature useful for studies of material properties. © 2016 Society of Chemical Industry 相似文献