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81.
Tatsuyuki Kawamura Tomohiro Fukuhara Hideaki Takeda Yasuyuki Kono Masatsugu Kidode 《Personal and Ubiquitous Computing》2007,11(4):287-298
In this paper we propose an object-triggered human memory augmentation system named “Ubiquitous Memories” that enables a user
to directly associate his/her experience data with physical objects by using a “touching” operation. A user conceptually encloses
his/her experiences gathered through sense organs into physical objects by simply touching an object. The user can also disclose
and re-experience for himself/herself the experiences accumulated in an object by the same operation. We implemented a prototype
system composed basically of a radio frequency identification (RFID) device. Physical objects are also attached to RFID tags.
We conducted two experiments. The first experiment confirms a succession of the “encoding specificity principle,” which is
well known in the research field of psychology, to the Ubiquitous Memories system. The second experiment aims at a clarification
of the system’s characteristics by comparing the system with other memory externalization strategies. The results show the
Ubiquitous Memories system is effective for supporting memorization and recollection of contextual events. 相似文献
82.
Tomohiro Higashihara Kumiko Kinoshita Seichi Sato Tamotsu Kozaki 《Applied Clay Science》2004,26(1-4):91
Sodium ions spiked with 22Na as a tracer were migrated by electromigration and electro-osmosis in the water-saturated compacted Na-montmorillonite at dry densities 1.0×103 kg m−3, under an electric potential gradient. Dissolved helium was also migrated by electro-osmosis in the montmorillonite. After migration, concentration profiles of the sodium ions and helium were obtained by γ-spectrometry and mass-spectrometric methods, respectively. From the profiles of both chemical species, not only migration due to electrokinetic phenomena but also mechanical dispersion was observed in the montmorillonite. The dispersion coefficients, Di, and apparent migration rates, Uia, of 22Na and helium were found in the compacted Na-montmorillonite at 1.0×103 kg m−3. The migration of helium in the montmorillonite under an electric potential gradient reflects that of water because helium migrates as an electrically neutral species. The parameters DHem, UHea, and αHe correspond to those of water. The mechanical dispersion coefficients, DNam, of 22Na+ ions are much smaller than those of water obtained by helium. The dispersivity parameters, αNa, for 22Na+ obtained from these DNa and UNaa values are 10−5 m and those for water (αHe) are 10−3 m. This indicates that 22Na+ ions migrate in different spaces than water in the compacted montmorillonite under a potential gradient. This finding suggests that the migration of Na+ ions occurs in the interlayer and/or on the outer surfaces of the montmorillonite; whereas dissolved helium migrates in the pore water. 相似文献
83.
Encapsulation of lead-free Sn/Zn/Bi solder alloy particles by coating with wax powder for improving oxidation resistance 总被引:2,自引:0,他引:2
Tomohiro Iwasaki Jeong Hwan Kim Shohei Mizuhashi Munetake Satoh 《Journal of Electronic Materials》2005,34(5):647-654
An encapsulation treatment of lead-free Sn/Zn/Bi solder powder was investigated for improving the oxidation resistance. Sn-8mass%Zn-3mass%Bi
alloy particles were coated with a wax (12-hydroxystearic acid) powder by means of a dry mechanical treatment method using
a ball mill. In order to determine the optimum operating conditions of the ball mill in the wax-coating treatments, the compressive
energy required for deforming a single Sn/Zn/Bi alloy particle was measured with an unconfined compression tester and the
mechanical energy applied to the alloy particles in the ball mill was estimated using the results of the compression test.
The optimum operating conditions were determined based on both the applied energy and the flowability of solder pastes, and
the wax-coated alloy particles maintaining the spherical shape were obtained under the conditions. The wettability test and
the solder balling test for the solder pastes containing the wax-coated alloy particles stored at room temperature in air
were carried out to evaluate the oxidation resistance performance. The wax-coated alloy particles had an excellent wettability
compared with the original alloy particles, and the oxidation resistance of the Sn/Zn/Bi solder powder was improved by the
encapsulation treatment. 相似文献
84.
Hiroyuki Miyamura Aya Suzuki Tomohiro Yasukawa Sh Kobayashi 《Advanced Synthesis \u0026amp; Catalysis》2015,357(18):3761-3761
85.
Alexandru I. Petrisor Sandra Szyjka Tomohiro Kawaguchi Pieter T. Visscher Robert Sean Norman Alan W. Decho 《International journal of molecular sciences》2014,15(1):850-877
Microspatial arrangements of sulfate-reducing microorganisms (SRM) in surface microbial mats (~1.5 mm) forming open marine stromatolites were investigated. Previous research revealed three different mat types associated with these stromatolites, each with a unique petrographic signature. Here we focused on comparing “non-lithifying” (Type-1) and “lithifying” (Type-2) mats. Our results revealed three major trends: (1) Molecular typing using the dsrA probe revealed a shift in the SRM community composition between Type-1 and Type-2 mats. Fluorescence in-situ hybridization (FISH) coupled to confocal scanning-laser microscopy (CSLM)-based image analyses, and 35SO4
2−-silver foil patterns showed that SRM were present in surfaces of both mat types, but in significantly (p < 0.05) higher abundances in Type-2 mats. Over 85% of SRM cells in the top 0.5 mm of Type-2 mats were contained in a dense 130 μm thick horizontal layer comprised of clusters of varying sizes; (2) Microspatial mapping revealed that locations of SRM and CaCO3 precipitation were significantly correlated (p < 0.05); (3) Extracts from Type-2 mats contained acylhomoserine-lactones (C4-, C6-, oxo-C6 C7-, C8-, C10-, C12-, C14-AHLs) involved in cell-cell communication. Similar AHLs were produced by SRM mat-isolates. These trends suggest that development of a microspatially-organized SRM community is closely-associated with the hallmark transition of stromatolite surface mats from a non-lithifying to a lithifying state. 相似文献
86.
87.
Hosokai S Kasiwaya Y Matsui K Okinaka N Akiyama T 《Environmental science & technology》2011,45(2):821-826
This paper describes the reduction of hematite with ammonia for ironmaking, in which the effect of temperature on the products was examined. The results showed that the reduction process began at 430 °C during heating, and with an increase in temperature, the reduction mechanism changed apparently from a direct reduction of ammonia (Fe(2)O(3) + 2NH(3) → 2Fe + N(2) + 3H(2)O) to an indirect reduction via the thermal decomposition of ammonia (2NH(3) → N(2) + 3H(2), Fe(2)O(3) + 3H(2) → 2Fe + 3H(2)O) at temperatures over 530 °C. The final product obtained at 600 and 700 °C was pure metallic iron, in contrast with that formed at 450 °C, that is, a mixture of metallic iron and iron nitride. The results suggest the possibility of using ammonia as a reducing agent for carbonless ironmaking, which is operated at a much lower temperature than 900 °C in conventional coal-based ironmaking. 相似文献
88.
Kimura A Kuwazawa S Wada Y Kyutoku Y Okamoto M Yamaguchi Y Masuda T Dan I 《Journal of food science》2011,76(3):S217-S224
Abstract: The effect of sensory and extrinsic attributes on consumer intentions to purchase the Japanese traditional fermented soybean product natto was evaluated using conjoint analysis. Six attributes with 2 levels each were chosen and manipulated: price (high compared with low), the country of origin of the soybeans (domestic compared with imported), stickiness (strong compared with moderate), smell (rich compared with moderate), attached seasonings (attached compared with no attached seasonings), and the environmental friendliness of the packaging (high compared with low). A fractional factorial design was applied and 8 hypothetical product labels were produced. A sample of 479 Japanese housewives ranked these product labels based on their purchase intentions. Overall purchase intention was affected by country of origin, attached seasonings, and price; those attributes accounted for 81.0%, while the sensory attributes of the product accounted for 19.0% of purchase intents. In order to estimate market segments for the natto products based on consumer preference, a cluster analysis was performed. It identified 4 segments of consumers: 1 oriented to attached seasonings, another conscious of the price, and the other 2 oriented to origins. The behavioral and demographic characteristics of the respondents had a limited influence on segment membership. Practical Application: This research was conducted to understand how consumers valuate various sensory and nonsensory product attributes based on their assessment of the overall product in the case of Japanese fermented soy product (natto). The data of this research would be of great importance both in understanding consumer behavior and in designing strategies for product development. 相似文献
89.
Daisuke Watanabe Keishi Nishio Yoshio Sakka Masataka Ohgaki Ian J. Davies Tomohiro Umeda Seiichiro Koda Kiyoshi Itatani 《Journal of Materials Science》2011,46(6):1956-1962
High-density β-calcium orthophosphate (β-Ca3(PO4)2, also called β-tricalcium phosphate: β-TCP) ceramics with submicrometer-sized grains were fabricated using a pulse-current
pressure firing route. The maximum relative density of the β-TCP compacts was 98.7% at 1050 °C and this was accompanied by
a translucent appearance. The mean grain size of the β-TCP compacts increased slightly with temperature to reach 0.78 μm at 1000 °C. However, upon further increasing the firing
temperature to 1050 °C the mean grain size increased significantly to 1.6 μm. The extent of plastic deformation during tensile
testing was examined at temperatures between 900 and 1100 °C using a strain rate in the range 9.26 × 10−5 to 4.44 × 10−4 s−1. The maximum tensile strain achieved was 145% for a test temperature of 1000 °C and strain rate of 1.48 × 10−4 s−1 and this was attributed to the relatively high density and small grain size. 相似文献
90.
Tomohiro Kubo 《Electrical Engineering in Japan》2005,150(2):28-34
It is well known that the linear quadratic regulators of finite dimensional linear systems have the insensitivity property. In this paper, as a particular class of infinite dimensional systems, a neutral delay‐differential system is considered as a plant. A class of linear quadratic regulators is constructed for the plant using a simple feedback law, which does not require real‐time either integral or derivative operations. The feedback gain is calculated by solving a finite dimensional linear matrix inequality. First, it is shown that the regulator satisfies the circle condition. Then, its sensitivity against the parameter variations is evaluated. In the single‐input case, it is done by calculating the absolute value of the sensitivity function. In the multi‐input case, it is done by the so‐called “comparison sensitivity” method where the sensitivities of the closed‐loop system and the open‐loop system are compared based on certain sensitivity indices. Procedures used for the investigation of the regulator's properties are based on natural extension of methods proposed by Perkins and Cruz for the finite dimensional case. As a result, it is found that the class of linear quadratic regulators of neutral systems, similarly to finite dimensional systems, has the insensitivity property. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(2): 28–34, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20013 相似文献