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排序方式: 共有403条查询结果,搜索用时 62 毫秒
41.
Ozasa K Shimizu Y Sakata R Sugiyama H Grant EJ Soda M Kasagi F Suyama A 《Radiation protection dosimetry》2011,146(1-3):272-275
Late health effects of exposure to atomic bomb radiation have been evaluated in survivors. A cohort of 120 321 people has been followed since 1950 for mortality, including the cause of death using the Japanese population registry system (Life Span Study), and for cancer incidence using population-based cancer registries. Findings have included a markedly increased risk of leukaemia several years after the exposure, increased risk of various malignant tumours several decades after the exposure and, more recently, findings of increased rates of non-cancer diseases such as cardiovascular diseases. 相似文献
42.
Horii Y Ohtsuka N Minomo K Nojiri K Kannan K Lam PK Yamashita N 《Environmental science & technology》2011,45(17):7517-7524
Distribution, characteristics, and global inventory of dioxins (polychlorinated dibenzo-p-dioxins [PCDDs] and dibenzofurans [PCDFs] and dioxin like polychlorinated biphenyls) in kaolin clays collected from 10 countries were investigated. Dioxins were found in all kaolin clay samples analyzed, at total concentrations ranging from 1.2 pg/g (Brazil) to 520,000 pg/g (USA). Dioxin concentrations in kaolin clays from a few countries (e.g., Brazil and UK) were lower than those reported for background soils in Japan. Dioxin profiles in kaolin clays were characterized by the domination of the congener octachlorodibenzo-p-dioxin (OCDD), and the concentrations of other congeners decreased in the order of reduction in the levels of chlorination. Furthermore, specific distribution of congeners, with predominant proportions of 1,4,6,9-substituted PCDDs within each homologue group, was found in most clay samples. The ratios of concentrations of PCDD to PCDF and 1,2,3,7,8,9-HxCDD to 1,2,3,6,7,8-HxCDD indicated differences in the profiles found for anthropogenic sources (including pentachlorophenol) and kaolin clays. Concentrations of PCDD/Fs in kaolin clays, except for American ball clays, did not exceed the environmental criteria set by the Law Concerning Special Measures against Dioxins in Japan. Based on the average concentrations measured in our study, inventories of PCDD/Fs from the production/usage of ball clays on a global scale were estimated to be 650 kg/yr; the corresponding value on a TEQ basis is 2400 g-TEQ/yr. More than 480 kg of OCDD is estimated to be released annually from the production of kaolin clays worldwide, suggesting that kaolin clays can be a major contributor for additional source of dioxins, especially OCDD, in the environment. 相似文献
43.
This work aims to identify the geographic distribution of photovoltaic (PV) energy potential considering the effect of temperature on PV system performance. A simple framework is developed that uses the JIS C 8907 Japanese industrial standard to evaluate the effects of irradiation and temperature on PV potential. The global distributions of PV potential and yearly performance ratio are obtained by this framework. Generally, the performance ratio decreases with latitude because of temperature. However, regions with high altitude have higher performance ratios due to low temperature. The southern Andes, the Himalaya region, and Antarctica have the largest PV potentials. Although PV modules with less sensitivity to temperature are preferable for the high temperature regions, PV modules that are more responsive to temperature may be more effective in the low temperature regions. The correlation between the estimates obtained by our framework and results from a more data-intensive method increases when the temperature effects are considered. 相似文献
44.
Batch-autoclave experiments have been conducted to evaluate the potential use of synthetic fluid inclusions as a simultaneous temperature–pressure (and fluid sampling) logging tool in deep-seated, high-temperature (>350 °C) geothermal systems. The application of synthetic fluid inclusions allows us to obtain information about thermal-pressure conditions in deep-seated geothermal systems, where conventional tools cannot be used because of the extreme temperature conditions. Fluid inclusions, up to 50 μm long, have been readily synthesized during 5-day autoclave experiments (conducted at 375–475 °C and 39–62 MPa) in pre-fractured, inclusion- and impurity-free artificial quartz. Inferred fluid inclusion (temperature–pressure) trapping conditions are calculated by deducing the intersection of isochores derived from microthermometric data for three sets of simultaneously trapped synthetic fluid inclusions in healed microfractures. Synthetic fluid inclusion logging offers a precise borehole temperature measurement technique without need of any pressure correction. Pressure estimates are less precise, although the method may be improved by using a combination of H2O–NaCl and H2O–KCl solutions/salinities, and fluid/quartz/amorphous silica systems that facilitate crack healing but trap fluids that do not homogenize at near-critical conditions. 相似文献
45.
Recently, numerous attempts have been made by researchers to understand the essence of complex phenomena (complex systems). In this paper, we consider biological systems in nature as being among the most complex systems. The purpose of this paper is to propose a method of realizing symbiotic phenomena such as mutual benefit, competition, and exploitation more generally than the Lotka–Volterra equation by using neural networks. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 140(1): 77–88, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.1172 Copyright © 2002 Scripta Technica 相似文献
46.
G Tsujimoto A Hirasawa T Sugawara T Awaji 《Canadian Metallurgical Quarterly》1998,62(17-18):1567-1571
Chlorethylclonidine (CEC) inactivation has been used as one criterion to subclassify the alpha1-adrenoceptors (AR); however, the extent of CEC inactivation can vary depending on the CEC treatment. By constructing the FLAG-tagged (N-terminus) and green fluorescent protein (GFP)-fused (C-terminus) alpha1-ARs, we have determined the relationship between CEC sensitivity and the cellular localization of alpha1-AR subtypes using COS-7 cells. In GFP-expressing cells, flow cytometry analysis with anti-FLAG N-terminus antibody detected strong fluorescent signals in most of alpha1B-AR-expressing cells, but low signals in alpha1A-AR-expressing cells. Further examination with confocal microscopy showed that fluorescent signals densely localized intra-cellularly in alpha1A-AR-expressing cells, while most of alpha1B-AR localized on the cell surface. Furthermore, radioligand binding studies with [125I]HEAT showed that CEC (10 microM) treatment of intact cells inactivated approximately 30-40% of alpha1A-AR and >90% of alpha1B-AR, while the CEC treatment of membrane preparations resulted in >80% decrease in the alpha1A-AR density and >90% of alpha1B-AR density, respectively. The results showed that the hydrophilic alkylating agent CEC inactivated only alpha1-AR on the cell surface irrespective of its subtype, and that the subtype-specific sorting is a major determinant for CEC inactivation of alpha1-AR. Subtype-specific cellular localization suggests a new class of functional properties that may explain the signal and functional diversity of homologous alpha1-AR (as well as other G protein-coupled receptors) subtypes. 相似文献
47.
The hydrothermal reactions of fibrous H2Ti4O9 particles with Ba(OH)2 solution in the presence of cationic surfactants of n-hexadecyltrimethylammonium hydroxide (HTMA-OH) and n-hexadecyltrimethylammonium
bromide (HTMA-Br) were investigated in a temperature range of 150–250 °C. H2Ti4O9 phase with layered structure was transformed to BaTiO3 phase in the Ba(OH)2–(HTMA-OH) and the Ba(OH)2–(HTMA-Br) solutions, and partially transformed to anatase phase in the Ba2+-free HTMA-OH and HTMA-Br solutions by topotactic structural transformation reactions under the hydrothermal conditions. The
cocoon-like BaTiO3 and titanium oxide particles were obtained after the hydrothermal reactions in the Ba(OH)2–(HTMA-OH) and HTMA-OH solution, respectively. These cocoon-like particles were formed by assembling the fibrous particles
in the surfactant solutions. 相似文献
48.
Cyclic voltammograms of hexaamminecobalt complex have been measured in high pH solutions. The spectroscopic result suggested that hydroamminecobalt complex adsorbed on the electrode surface during cathodic polarization, and this species grew to form cobalt hydroxide after a long time of electrolysis. In the anodic process, the reaction orders for pH and NH3 were both |1|. Based on these results, the reaction mechanism has been discussed.The effect of light on the electrode process has been studied by irradiating with ultraviolet light of the 254 nm mercury resonance line. It has been indicated that the hydroxoammine complex is decomposed to cobalt hydroxide and free ligand under light. 相似文献
49.
Radiocardiography has been widely used as a method for the quantification of cardiac output by applying the principle of the dye dilution method. This paper deals with an automatic analyzing system of radiocardiograms and a parameter estimation procedure using a linear system made up of four compartments with two time delays as a model of transport process in the blood circulatory system. The parameter estimation procedure named the window method in frequency domain is very effective for shortening the computing time and can be easily performed using a minicomputer. Parameter sensitivity analysis is also applied to study behavior of parameters on the model. Some analyzed results of radiocardiograms are shown and it is verified that the procedure is sufficiently useful and efficient for routine clinical use. 相似文献
50.
Tomio Chiba Mitsuyasu Kido Junzou Kawakami Katsuhiko Yoneda Tadao Kawai Kotaro Hirasawa 《Electrical Engineering in Japan》1994,114(5):31-43
Control and protection equipment in power systems requires higher sensitivity and operational reliability to meet today's changing power system requirements. The voltage-measuring deviation requirement for advanced voltage and var control equipment is less than 0.1 percent under conditions of harmonic distortion in the voltage waveform and power-system frequency variation. Studies on digital signal processing suitable for electric power systems showed that these requirements are satisfied using fast sampling and very fast 32-bit floating point operations by a Digital Signal Processor (DSP). This paper describes the design philosophy of a high-precision power system voltage-measuring method using fast sampled data. In addition, total voltage-measuring deviation characteristics under a combination of the techniques are described along with digital filter characteristics, frequency-measuring deviation characteristics, frequency variation versus gain-compensation characteristics of a digital filter, and peak value operating principles. 相似文献