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排序方式: 共有883条查询结果,搜索用时 15 毫秒
131.
Yoshikawa J Amachi S Shinoyama H Fujii T 《Journal of Bioscience and Bioengineering》2007,103(5):491-493
beta-Fructofuranosidase I (FFase I) formed by Aureobasidium pullulans DSM 2404 was purified. The enzyme had a molecular weight of about 430 kDa, was not affected by various metal ions and showed high transfructosylating activity. The yield of fructooligosaccharides production using purified FFase I was 62%. 相似文献
132.
Masakazu Yoshikawa Jun-ichiro Izumi Takashi Ooi Toshio Kitao Michael D. Guiver Gilles P. Robertson 《Polymer Bulletin》1998,40(4-5):517-524
SUMMARY
Molecularly imprinted polymeric membranes were prepared from carboxylated polysulfone. Membranes imprinted by Z-D-Glu recognize
the D-isomer in preference to the corresponding L-isomer, and vice versa. The amino acid preferentially adsorbed by the membrane
was also selectively permeated by electrodialysis.
Received: 22 January 1998/Accepted: 20 February 1998 相似文献
133.
Adhesion properties of CVD diamond film on binder-less sintered tungsten carbide prepared by the spark sintering process 总被引:1,自引:0,他引:1
This paper describes the adhesion property of chemical-vapor-deposited (CVD) diamond film on tungsten carbide (WC) bodies prepared by spark sintering without a binder. WC bodies ranging from 70 to 95% of density ratio have been sintered under different sintering conditions, and their mechanical properties, such as hardness and bending strength, have been measured. High-quality diamond films with a higher nucleation density compared to that on WC–Co have been deposited on this WC substrate using the microwave plasma CVD method. A comparison study using indentation tests shows that the adhesive strength of diamond films on this binder-less sintered WC is remarkably superior to that on WC–Co, which is believed to result from the increase in diamond nucleation density, the enhanced mechanical bonding between the substrate and the diamond film and the well-matching of thermal expansion coefficients caused by the absence of the fatal obstacle of cobalt. Moreover, an increase in adhesive strength has occurred on the binder-less sintered WC with lower density ratios. 相似文献
134.
Zhixin Qin Masakazu Kobayashi Akihiko Yoshikawa 《Journal of Materials Science: Materials in Electronics》1999,10(3):199-202
X-ray diffraction reciprocal space maps and pole figures were used to analyse the cubic GaN epitaxial layers grown on (0 0 1) GaAs by r.f. plasma source MBE; the presence of hexagonal phase in cubic GaN layers was detected by high resolution x-ray analysis and the relationships among various crystal axes of cubic and hexagonal phase GaN were analysed with respect to V/III source-supply ratio. As for the growth conditions of the epitaxial layers, the V/III ratio was found to drastically affect the quality of the layers. High-temperature growth under near-stoichiometric conditions was necessary to obtain high quality epitaxial layers. It was found that inclusion of the hexagonal phase in the cubic GaN layers could be less than 0.4%, though previously reported typical c-GaN epitaxial layers included as much as 10–20% hexagonal phase GaN. On the basis of the measurements and analyses of reciprocal space maps and pole figures, it was revealed that the orientation of crystal axes of the hexagonal phase was unique in the present GaN epitaxial layers and they were different from those of previously reported c-GaN epitaxial layers. 相似文献
135.
A simulation model for predicting air quality along urban main roads is being studied. The objective of the model is to predict the effects on air quality of various road-related parameters such as configurations of roads and surrounding buildings as well as traffic flow, chemical reactions, and other related phenomena. In this paper, the development of an atmospheric diffusion model, which will be the platform of the whole simulation model, is reported. A new concentration diffusion coefficient model is proposed, in which the effect of vehicle wind is taken into account. By comparing with field experiments in which the diffusing tracer gas concentration was measured in a real street canyon, the validity of the simulation model is verified. Also, the new diffusion coefficient model is found to be capable of improving predictive accuracy of air quality around a street canyon. © 1998 Scripta Technica, Heat Trans Jpn Res, 27(7): 483–496, 1998 相似文献
136.
Kashii M Fujisawa R Adachi H Mori Y Sasaki T Koga Y Takano K Kanaya S Matsumura H Inoue T Murakami S Sugamoto K Yoshikawa H 《Journal of Bioscience and Bioengineering》2006,102(4):372-374
We developed a novel technique for detaching protein crystals from glass capillary tube using the counter diffusion crystallization technique by femtosecond laser irradiation. X-ray diffraction analysis demonstrated that femtosecond laser irradiation has little effect on crystallinity. This technique will contribute to progress in structural genomics as a powerful tool. 相似文献
137.
Tomoaki Namioka Yuki Nagai Kunio Yoshikawa Taijin Min 《International Journal of Hydrogen Energy》2012
Durability of a nickel and scandia-stabilized zirconia cermet anode against toluene in hydrogen was evaluated in this paper. Anode deterioration was judged by the loss of elemental nickel from a surface of an anode. Elemental nickel loss was observed when the toluene concentration was 3 or 10 g/Nm3, steam to carbon ratio was 1, and current density was 0.5 A/cm2 at both temperatures: 1073 K and 1173 K. Therefore the tolerance criterion must be less than 3 g/Nm3 in hydrogen in the experimental conditions. However, the deterioration can be mitigated to some extent by increasing the operating temperature, steam-to-carbon ratio, or current density. Anode deterioration was also mitigated when hydrogen concentration in the fuel gas was nearly identical to that of wood gas. The influence of hydrogen concentration in the fuel gas on deterioration may be substantial. The loss of elemental nickel could not be detected instantaneously by electrochemical diagnosis. 相似文献
138.
Makoto Sugiyama Yutaka FujimotoTakayuki Yanagida Daisuke Totsuka Shunsuke KurosawaYoshisuke Futami Yuui YokotaValery Chani Akira Yoshikawa 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2012,664(1):127-131
Er-doped Lu3Al5O12 (Er:LuAG) single crystalline scintillators with different Er concentrations of 0.1, 0.5, 1, and 3% were grown by the micro-pulling-down (μ-PD) method. The grown crystals were composed of single-phase material, as demonstrated by powder X-ray diffraction (XRD). The radioluminescence spectra measured under 241Am α-ray excitation indicated host emission at approximately 350 nm and Er3+ 4f-4f emissions. According to the pulse height spectra recorded under γ-ray irradiation, the 0.5% Er:LuAG exhibited the highest peak channel among the samples. The γ-ray excited decay time profiles were well fitted by the two-component exponential approximation (0.8 μs and 6-10 μs). 相似文献
139.
Sakai K Obata K Yoshikawa M Takano R Shibata M Maeda H Mizutani A Terada K 《Drug development and industrial pharmacy》2012,38(10):1254-1261
Purpose: To design a high drug loading formulation of self-microemulsifying/micelle system. Methods: A poorly-soluble model drug (CH5137291), 8 hydrophilic surfactants (HS), 10 lipophilic surfactants (LS), 5 oils, and PEG400 were used. A high loading formulation was designed by a following stepwise approach using a high-throughput formulation screening (HTFS) system: (1) an oil/solvent was selected by solubility of the drug; (2) a suitable HS for highly loading was selected by the screenings of emulsion/micelle size and phase stability in binary systems (HS, oil/solvent) with increasing loading levels; (3) a LS that formed a broad SMEDDS/micelle area on a phase diagram containing the HS and oil/solvent was selected by the same screenings; (4) an optimized formulation was selected by evaluating the loading capacity of the crystalline drug. Aqueous solubility behavior and oral absorption (Beagle dog) of the optimized formulation were compared with conventional formulations (jet-milled, PEG400). Results: As an optimized formulation, d-α-tocopheryl polyoxyethylene 1000 succinic ester: PEG400?=?8:2 was selected, and achieved the target loading level (200?mg/mL). The formulation formed fine emulsion/micelle (49.1?nm), and generated and maintained a supersaturated state at a higher level compared with the conventional formulations. In the oral absorption test, the area under the plasma concentration-time curve of the optimized formulation was 16.5-fold higher than that of the jet-milled formulation. Conclusions: The high loading formulation designed by the stepwise approach using the HTFS system improved the oral absorption of the poorly-soluble model drug. 相似文献
140.
Nabeshi H Yoshikawa T Matsuyama K Nakazato Y Arimori A Isobe M Tochigi S Kondoh S Hirai T Akase T Yamashita T Yamashita K Yoshida T Nagano K Abe Y Yoshioka Y Kamada H Imazawa T Itoh N Kondoh M Yagi K Mayumi T Tsunoda S Tsutsumi Y 《Nanotechnology》2012,23(4):045101
We previously reported that well-dispersed amorphous nanosilicas with particle size 70 nm (nSP70) penetrate skin and produce systemic exposure after topical application. These findings underscore the need to examine biological effects after systemic exposure to nanosilicas. The present study was designed to examine the biological effects. BALB/c mice were intravenously injected with amorphous nanosilicas of sizes 70, 100, 300, 1000 nm and then assessed for survival, blood biochemistry, and coagulation. As a result, injection of nSP70 caused fatal toxicity, liver damage, and platelet depletion, suggesting that nSP70 caused consumptive coagulopathy. Additionally, nSP70 exerts procoagulant activity in vitro associated with an increase in specific surface area, which increases as diameter reduces. In contrast, nSP70-mediated procoagulant activity was absent in factor XII-deficient plasma. Collectively, we revealed that interaction between nSP70 and intrinsic coagulation factors such as factor XII, were deeply related to nSP70-induced harmful effects. In other words, it is suggested that if interaction between nSP70 and coagulation factors can be suppressed, nSP70-induced harmful effects may be avoided. These results would provide useful information for ensuring the safety of nanomaterials (NMs) and open new frontiers in biological fields by the use of NMs. 相似文献