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41.
Surface erosion in pyrolytic graphite by 100 keV 4He+ and 200 keV H+2 ion bombardment has been observed by scanning electron microscopy. The particle fluence ranged from 1 × 1017 to 5 × 1018 particles/cm2. Although the surface is eroded at 1 × 1017 particles/cm2 in helium bombardment, it is not eroded so heavily even at 5 × 1017 particles/cm2 in hydrogen bombardment. In helium bombardment flaking is significantly observed at 1 × 1018 particles/cm2, and a cone structure appears at 5 × 1018 particles/cm2, which is produced after the first cover flakes off completely. In hydrogen bombardment at 1 × 1018 particles/cm2, many circular blisters are formed which are sputtered off at 5 × 1018 particles/cm2. The surface roughness of the target also affects the erosion. 相似文献
42.
Minamida K Shiga K Sujaya IN Sone T Yokota A Hara H Asano K Tomita F 《Journal of Bioscience and Bioengineering》2005,99(3):230-236
The effects of difructose anhydride III (di-D-fructofuranose-1,2':2,3'-dianhydride; DFA III) administration (3% DFA III for 4 weeks) on rat intestinal microbiota were examined using denaturing gradient gel electrophoresis (DGGE). According to DGGE profiles, the number of bacteria related to Bacteroides acidofaciens and uncultured bacteria within the Clostridium lituseburense group decreased, while that of bacteria related to Bacteroides vulgatus, Bacteroides uniformis and Ruminococcus productus increased in DFA III-fed rat cecum. In the cecal contents of DFA III-fed rats, a lowering of pH and an increase in short chain fatty acids (SCFAs), especially acetic acid, were observed. The DFA III-assimilating bacterium, Ruminococcus sp. M-1, was isolated from the cecal contents of DFA III-fed rats. The strain had 98% similarity with R. productus ATCC 27340T (L76595), and mainly produced acetic acid. These results confirmed that the bacteria harmful to host health were not increased by DFA III administration. Moreover, DFA III stimulated the growth of Ruminococcus sp. M-1 producing acetic acid, which may alter the intestinal microbiota towards a healthier composition. It is expected that DFA III would be a new candidate as a prebiotic. 相似文献
43.
44.
Y Imai S Sone S Serizawa SH Bae N Imai M Hasegawa K Yamashita 《Canadian Metallurgical Quarterly》1995,55(8):562-568
The magnetic resonance (MR) imaging and computed tomography (CT) findings in four patients (five kidneys) with non-Hodgkin's lymphoma involving the kidneys and perirenal spaces are presented. The patterns of disease in each case were as follows: bilateral renal nodules, infiltration in the perirenal space, infiltration in the perirenal space with renal involvement, and direct invasion from contiguous retroperitoneum. On plain CT, the lesions showed slight hyperdensity (three kidneys) and isodensity (two kidneys) as compared with normal renal parenchyma. But all lesions appeared as hypodense masses with more definite margins after contrast enhancement. MR imaging findings showed iso- or slight hypointense masses on T1-weighted images and definite hypointense masses on T2-weighted images as compared with the signal intensity of the renal cortex. Dynamic imaging and conventional delayed T1-weighted imaging following Gd-DTPA injection showed no significant enhancement of the lesions. In comparison with contrast enhanced CT, despite its poorer resolution, T2-weighted MR imaging showed nearly the same accuracy in the evaluation of number and extent of the lesions without contrast medium administration. MR imaging was also useful to evaluate the patency of vessel lumen surrounded by tumor mass and to determine the location and extent of huge lesions by its multiplanar imaging capabilities. 相似文献
45.
By use of carbon black containing quaternary ammonium carboxylate (COO?N+R4) groups as catalyst, the anionic ring opening polymerization of β-propiolactone (PL) was carried out at 50°C. Although carbon black itself was unable to initiate the polymerization of PL, carbon black containing COO?N+R4 groups, which was prepared by the reaction of carboxyl groups with corresponding quaternary ammonium hydroxide, was found to be able to initiate the polymerization. The carbon black obtained from the polymerization gave a stable colloidal dispersion in an organic solvent, and it was confirmed that the polyester formed was effectively grafted onto the surface. In addition, the effect of quaternary ammonium countercation on the polymerization was investigated. 相似文献
46.
Spectrum-efficient and scalable elastic optical path network: architecture, benefits, and enabling technologies 总被引:1,自引:0,他引:1
Jinno M. Takara H. Kozicki B. Tsukishima Y. Sone Y. Matsuoka S. 《Communications Magazine, IEEE》2009,47(11):66-73
The sustained growth of data traffic volume calls for an introduction of an efficient and scalable transport platform for links of 100 Gb/s and beyond in the future optical network. In this article, after briefly reviewing the existing major technology options, we propose a novel, spectrum- efficient, and scalable optical transport network architecture called SLICE. The SLICE architecture enables sub-wavelength, superwavelength, and multiple-rate data traffic accommodation in a highly spectrum-efficient manner, thereby providing a fractional bandwidth service. Dynamic bandwidth variation of elastic optical paths provides network operators with new business opportunities offering cost-effective and highly available connectivity services through time-dependent bandwidth sharing, energy-efficient network operation, and highly survivable restoration with bandwidth squeezing. We also discuss an optical orthogonal frequency-division multiplexing-based flexible-rate transponder and a bandwidth-variable wavelength cross-connect as the enabling technologies of SLICE concept. Finally, we present the performance evaluation and technical challenges that arise in this new network architecture. 相似文献
47.
48.
A Yamamoto E Shimizu E Takeuchi H Houchi H Doi H Bando T Ogura S Sone 《Canadian Metallurgical Quarterly》1999,56(2):129-133
To clarify the host immune response and explore a new serological marker of lung cancer, we examined serum c-Myc antigens and auto-antibodies against c-Myc in 68 lung cancer patients and 30 healthy volunteers using bacterially synthesized glutathione S-transferase c-Myc fusion proteins and immunoblotting. The detection rate of anti-c-Myc antibodies was 13.2% (9/68) in lung cancer patients and 3.3% (1/30) in healthy volunteers. These anti-c-Myc antibodies were directed toward exon 2 alone (4/68), exon 3 alone (1/68), and both exon 2 and exon 3 (4/68) of c-Myc. Circulating c-Myc antigen was not detected in any individuals with lung cancer and normal controls. Age, sex, performance status, histology, stage, smoking history, and prior treatment of the patients with and without anti-c-Myc antibodies were not significantly different. The low incidence of anti-c-Myc antibodies and c-Myc antigens in peripheral blood suggests that these examinations are not useful in the serological diagnosis of lung cancer. 相似文献
49.
M. Yoshida H. Yabuta S. Yamamichi H. Yamaguchi S. Sone K. Arita T. Iizuka S. Nishimoto Y. Kato 《Journal of Electroceramics》1999,3(2):123-133
Electron cyclotron resonance (ECR) plasma chemical vapor deposition (CVD) of (BaSr)TiO3 dielectrics is reviewed. The oxygen plasma lowered the crystallization temperature and carbon contamination. (BaSr)TiO3 CVD process was developed under conditions of relatively low deposition rate of 1.1 nm/min and a relatively low deposition temperature of 550°C. Utilizing this process, we developed a gigabit dynamic random access memory (DRAM) capacitor technology involving the preparation of a thin (BaSr)TiO3 capacitor dielectric over a RuO2/Ru storage node contacting a TiN/TiSi
X
/poly-Si plug. The ECR plasma CVD enabled uniform deposition of gigabit-DRAM-quality (BaSr)TiO3 films on the electrode sidewalls. The storage node contact improved in endurance against oxidation, by fabricating the buried-in TiN/TiSi
X
plug (TiN-capped plug) under the RuO2/Ru storage node. (BaSr)TiO3 films with a small equivalent SiO2 thickness of 0.38 nm and a leakage current density of 8.5×10–7 A/cm2 at an applied voltage of 1.0 V, were obtained without any further annealing process. An equivalent SiO2 thickness of 0.40 nm on the RuO2 sidewall was also achieved. It is concluded that this technology has reached the requirements for gigabit DRAM capacitors. 相似文献
50.
Gold nano-rod array membranes (Au-NRM) were prepared by modification of the template method. A simple two-electrode device was assembled by holding an electrolyte solution between the Au-NRM and a transparent electrode. Small reflectance changes (less than 2%) in the visible band were induced on the Au-NRM surface by applying a DC voltage to the device. These changes could be visually observed. It was found based on a further evaluation that the reflectance changes responded very fast (less than 100 ms) to the DC voltage application, and were stable during the switching repetition (over 5000 times). When the cyclic scanning of the applied voltage to the device was carried out between -1.5 V and +1.5 V, the reflectance changes were increased over +1.0 V (-1.0 V). It was suggested from these experimental results that the reflectance changes were attributed to the surface oxidation and the deformation or mechanical motion of the Au nano-rod. 相似文献