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101.
Abstract The synthesis, reactions and crystal structure of Isophthalic dimethyl oxaziridine are presented here. The synthesis was carried out utilising hydroxylamine-O-sulfonic acid to produce oxaziridine unsubsituted on the nitrogen, which was reacted in situ with isophthaloyl dichloride to give the corresponding Isophthatic dimethyl oxaziridine. It is an analogue of Isophthalic 2-methyl aziridine, a product which has been used as a bonding agent for Composite Solid Propellant. The oxaziridine was tested in oxidative reactions of sulfides to sulfoxides, styrene oxide, cyclohexene to cyclohexene oxide, and 1-(2-cyclohexenyl)-2-propanone to [1-(2-cyclohexenyl)-2-propanone] oxide. 相似文献
102.
Akira Saito Atsushi Kawamoto Masakatsu Kuroishi Hideo Nakai Shintaro Yamasaki 《Structural and Multidisciplinary Optimization》2017,55(3):987-999
Orthotropic elastic moduli of composite structures can be identified by nonlinear least squares fit between measured and computed natural frequencies. However, due to measurement errors contained in the measured natural frequencies and mode shapes, the process of elastic moduli identification is error-prone. This paper proposes an efficient method to estimate the errors in the elastic moduli caused by the measurement errors in the natural frequencies. The method utilizes an efficient semi-analytic expression of the sensitivities of the eigenvalues with respect to the orthotropic elastic moduli. First, the first-order approximation of the analytic sensitivity of orthotropic elastic moduli with respect to the measurement errors is introduced. The approximation is then used to estimate the variability of the identified elastic moduli due to the measurement errors. It is shown that the aspect ratio of the test specimen greatly affects the standard deviation of the identified elastic moduli. Second, using the first-order approximation, the effects of aspect ratio of the test specimen as well as the values of the elastic moduli are further investigated. Based on the results of numerical experiments, guidelines for the dimension of the test specimen for the elastic moduli identification are proposed. 相似文献
103.
Atsuo Honda Koichiro Tezuka Tomohito Okamura Kaoru Kawamoto Shoji Shimizu Kohei Harada Takahito Tanabe Tatsuya Shirakawa Tomohiro Takahashi 《Electrical Engineering in Japan》2019,206(4):22-35
Osaka Gas Co., Ltd., jointly with NTT DATA Mathematical Systems Inc., has developed unit‐commitment model for optimizing dispatch of power generation units. Main purpose of this development is to simulate the future world of electric power system in accordance with national energy policy aiming to introduce large amount of renewable energy as well as vitalized cross‐border power exchange via PX market to enhance economically‐efficient power system operation. The model incorporates not only constraints of supply‐demand balance but also constraints of operating reserves, regulation reserves, maximum CO2‐emissions, etc. 相似文献
104.
Yosuke Kawamoto 《Journal of Nuclear Science and Technology》2017,54(2):213-222
The accurate prediction of the decay heat is essential, especially for nuclear power plant safety purposes. However, it is known that the decay heat predicted by nuclear fuel burn-up calculations is uncertain because of uncertainty of nuclear data employed in the calculations. If the decay heat uncertainty can be reduced, the safety margin of the predicted decay heat can also be reduced, and feasible design ranges of various types of equipments related to the decay heat can be extended. In the present study, we use the nuclear data adjustment method for the decay heat uncertainty reduction with several types of the experimental data. As a result, we clarify that the decay heat uncertainty with short- and long-term cooling periods can be reduced by this method with appropriate experimental data. 相似文献
105.
Jianzhong Huang Tsunehiro Aki Kazutaka Hachida Toshihiro Yokochi Seiji Kawamoto Seiko Shigeta Kazuhisa Ono Osamu Suzuki 《Journal of the American Oil Chemists' Society》2001,78(6):605-610
More than 300 strains of microorganisms producing polyunsaturated fatty acids (PUFA) were newly isolated from coastal seawater
in the Seto Inland Sea and around Iriomote Island, Japan, by the baiting method. The profiles of PUFA from docosahexaenoic
acid (DHA)-producing strains could be classified into four types. A strain, named KK17-3, was chosen for further study owing
to its high DHA content (52.1% of total fatty acid) and wide range of PUFA (76.1%) including arachidonic, eicosapentaenoic,
and docosapentaenoic acids as well as DHA. Glucose and tryptone were the optimal carbon and nitrogen sources, respectively,
in a medium with salinity at 75% that of seawater. The PUFA contents in polar lipids (22.1% of total lipid), in which the
DHA content was 39.3%, were higher than those in neutral lipids and glycolipids. Molecular phylogenetic analysis of 18S rRNA
gene sequences showed KK17-3 to be a thraustochytrid. It also was observed to possess a life cycle composed of vegetative
cells without successive bipartition, zoosporangium, and zoospore stage. Classification by the chemotaxonomic criterion based
on PUFA compositions also supported this assignment. 相似文献
106.
Shintaro Yamasaki Tsuyoshi Nomura Kazuo Sato Naobumi Michishita Yoshihide Yamada Atsushi Kawamoto 《International journal for numerical methods in engineering》2012,89(10):1272-1295
In the last decade, metamaterials have been gaining attention and have been investigated because of their unique characteristics, which conventional materials do not have, such as negative refraction indexes. However, it is sometimes difficult to design metamaterials on the basis of experience and theoretical considerations because the relationship between their electromagnetic characteristics and structure is often vague. A mathematical structural design methodology targeting metamaterials may therefore be useful for expanding the engineering applications of metamaterials in industry. In this paper, a new level set‐based topology optimization method is proposed for designing composite right‐ and left‐handed transmission lines, each of which consists of a waveguide and periodically located dielectric resonators. Such transmission lines function as a fundamental metamaterial. In the proposed method, the shape and topology of the dielectric resonators are represented by the level set function, and topology optimization problems are formulated on the basis of the level set‐based representation. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
107.
Yamasaki T Aki T Shinozaki M Taguchi M Kawamoto S Ono K 《Journal of Bioscience and Bioengineering》2006,102(4):323-327
The industrial production of barley shochu, a distilled alcoholic beverage, results in distillery waste that is currently incinerated or disposed of in landfills, causing environmental pollution. The supernatant of distillery waste contains organic matter such as proteins ( approximately 2.5%) and amino acids ( approximately 0.2%). This study demonstrates that the utilization of distillery wastewater as a sole nitrogen source enables a marine thraustochytrid, Schizochytrium sp. strain KH105, to propagate and accumulate valuable lipids including docosahexaenoic acid (DHA) and astaxanthin. Under optimized culture conditions, the highest DHA and astaxanthin yields were obtained at 3.4 g/l and 7.7 mg/l, respectively, after 4 or 5 d of cultivation in a 3-l jar fermentor. The chemical oxygen demand of the wastewater was reduced by 35%. About 67% of crude protein content and 85% of total free amino acid content also decreased in the culture supernatant. The thraustochytrid therefore serves to upgrade the distillery by-product to one containing value-added lipids for functional foods as well as to regulate the environmental contamination. 相似文献
108.
Varma HK Yokogawa Y Espinosa FF Kawamoto Y Nishizawa K Nagata F Kameyama T 《Journal of materials science. Materials in medicine》1999,10(7):395-400
Biomimetic growth of calcium phosphate compound on cotton sheets treated with tetraethoxy silane and soaked in simulated body fluid solution was studied using scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), micro-Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometry (XRD). Micro-FTIR and EDAX results show that silicon was coupled to the cotton fiber when cotton was treated with tetra-ethoxy silane (TEOS) at 125°C for 1 h. Calcium phosphate nucleation started to occur on the surface of TEOS-treated cotton fibers upon immersion in 1.5×SBF (simulated body fluid solution) within 3 days and after 20 days, all the fiber surfaces were found covered with a thick and porous coating of calcium phosphate. The Ca and P determined by inductively coupled plasma spectroscopy (ICP) analysis revealed that the Ca/P ratio as well as the amount of calcium phosphate coating depends on the soaking time in SBF solution. © 1999 Kluwer Academic Publishers 相似文献
109.
Daisuke Murai Atsushi Kawamoto Tsuguo Kondoh 《International journal for numerical methods in engineering》2020,121(10):2246-2261
This article describes a numerical solution to the topology optimization problem using a time-evolution equation. The design variables of the topology optimization problem are defined as a mathematical scalar function in a given design domain. The scalar function is projected to the normalized density function. The adjoint variable method is used to determine the gradient defined as the ratio of the variation of the objective function or constraint function to the variation of the design variable. The variation of design variables is obtained using the solution of the time-evolution equation in which the source term and Neumann boundary condition are given as a negative gradient. The distribution of design variables yielding an optimal solution is obtained by time integration of the solution of the time-evolution equation. By solving the topology optimization problem using the proposed method, it is shown that the objective function decreases when the constraints are satisfied. Furthermore, we apply the proposed method to the thermal resistance minimization problem under the total volume constraint and the mean compliance minimization problem under the total volume constraint. 相似文献
110.