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991.
992.
T Hattori T Fujisawa K Sasaki Y Yutani T Nakanishi K Takahashi M Takigawa 《Canadian Metallurgical Quarterly》1998,245(3):679-683
Two types of 47 kDa antigen specifically recognized by sera from rheumatoid arthritis (RA) patients were isolated from the membrane fraction of a human chondrosarcoma-derived chondrocytic cell line (HCS-2/8) by a 2-step procedure: preparative SDS-PAGE and reverse-phase HPLC. An N-terminal amino acid sequence in one of the 47 kDa antigens, named RA-A47, had 81% homology to that deduced from the DNA sequence of the colligin gene which is reported as human hsp47 gene, and 100% homology to that deduced from the DNA sequence of colligin-2 gene, a homologue of colligin. The RA-A47 cross-reacted with a monoclonal antibody raised against chick heat shock protein (Hsp) 47 and bound to gelatin. The expression of the ra-a47 gene was enhanced by heat shock treatment and TGF-beta stimulation. These findings suggest that RA-A47 is a Hsp47-like protein, presumably the product of the colligin-2 gene, and that a collagen-specific molecular chaperone(s) such as Hsp47 and/or RA-A47 is involved in cartilage destruction in RA. 相似文献
993.
Abstract. The focus of the Japanese local telecommunications policy is shifting towards solving the problem of the digital divide that accompanies the spread of high-speed and broadband services. The article estimates a translog cost function of two outputs – the standard telephone service and the leased circuit service – and measures the regional gap of those stand-alone costs and incremental costs. The main point we make is that the cost gap for the leased circuit service is larger than that for the standard telephone service among the 11 Nippon Telegraph and Telephone (NTT) regional offices. 相似文献
994.
Acetic acid simulating a persistent organic compound in water was decomposed by a discharge on water using a thin blade electrode. The thin blade electrode facilitates the generation of wide‐ranging discharges on water. The effect of differences in the species of the supply gas and the discharge power on the decomposition of acetic acid was investigated. Compared with argon, when helium was used, a larger amount of acetic acid was decomposed. Experiments also confirmed that the decomposition rate of acetic acid rose with the discharge power. It was also found that the decomposition efficiency was improved when the discharge power was reduced. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(1): 1–10, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22318 相似文献
995.
996.
A novel beta-glucosidase, which is inducible and capable of catalyzing the hydrolysis of sennosides, was purified from Bifidobacterium sp. strain SEN with Triton X-100 solubilization and DEAE-cellulose column chromatography, by which hydrolytic activities toward sennoside B, 4-methylumbelliferyl beta-glucoside (MUG), and p-nitrophenyl beta-glucoside (pNPG) were obtained together in the same eluted fractions. The activity was stable against detergents such as sodium dodecyl sulfate (SDS) and Triton X-100, but was denatured by SDS and beta-mercaptoethanal when heated. The final preparation was shown to be nearly homogeneous on SDS-polyacrylamide gel electrophoresis (PAGE) either after the enzyme was denatured or when it was not denatured. In the non-denaturing SDS-PAGE, a single protein band hydrolyzed MUG on the gel. In the denaturing SDS-PAGE, the subunit mass of the enzyme was estimated to be 110 kDa. The enzyme was optimally active at pH 6.0 for hydrolysis of sennoside B and MUG. Km values for sennoside B and MUG are 0.94 and 0.53 mM, respectively. The enzyme also catalyzed the hydrolysis of pNPG, amygdalin, geniposide and salicin. It was less active against methyl beta-glucoside and incapable of hydrolyzing cellobiose. The beta-glucosidase activity was inhibited by deoxynojirimycin and p-chloromercuribenzenesulfonic acid, but was less susceptible to several metals (FeSO4, ZnCl2, and CuSO4), and 5,5'-dithio-bis(2-nitrobenzoic acid). 相似文献
997.
A new type of induction motor with a built-in torque sensor (called a ‘torque-sensor motor’) has been developed in order to monitor grinding torque. Its rotor shaft consists of a hollow shaft and torsion bar, each of which has a disc with equiangularly located magnets. The torque output is calculated by microcomputer from the time delay of pulses generated in detecting coils. This toque sensor has good linearity. Torque ripple and zero-point drift caused by rotational speed change are estimated to be less than 1 Nm. It is so sensitive that it can detect torque ripple from rotational error of the driving belts on the grinding machine. Further, it can accurately monitoring grinding torque by using a low pass filter to remove such torque ripple. It can also be used to estimated the time constant of the grinding wheel and workpiece system in the transient torque situation of a grinding cycle. The performance of the grinding wheel motor is as good as that of a conventional motor. 相似文献
998.
Hirokazu Ito Rashmi Kumari Masahiro Takatani Tadashi Okamoto Hidehiro Hattori Ippei Fujiyoshi 《Polymer Engineering and Science》2008,48(1):168-176
The dispersion of filler in resin is an important factor which determines the mobility of a compound in a molder and also the mechanical properties of molded products in wood/plastic composite, especially with high wood filler content. In this report, the dispersion of components in the melt‐mixture of a compound in response to the size of cellulose filler and resin content was examined for compounds with a high content of cellulose in polypropylene by the evaluation of viscoelasticity using a cone rheometer, and the following conclusions were obtained: (1) The viscoelasticity measured by a cone rheometer was dependent on the dispersion state of the compound, and it was confirmed that the presented evaluation method of viscoelasticity affords information relevant to the dispersion state of filler in a compound; (2) On the basis of the viscoelastic evaluation of compounds with different resin contents, a model for the distribution of cellulose and resin is proposed in terms of the tangle of fibers; (3) Viscoelastic analysis showed that cellulose size has an influence on the tangle of fibers; (4) The results of viscoelasticity and mechanical properties of molded products suggested that an important factor determining the tangle of fibers is the average aspect ratio. The proposed analysis of viscoelasticity presents a simple technique for estimating the dispersion state of a compound with high filler content, which is hardly possible by conventional fluid evaluation methods. POLYM. ENG. SCI., 48:168–176, 2008. © 2007 Society of Plastics Engineers 相似文献
999.
Kikuchi T Okazaki M Kimura SD Motobayashi T Baasansuren J Hattori T Abe T 《Journal of hazardous materials》2008,154(1-3):294-299
The objective of this study is to assess the applicability of a commercial magnesium oxide (MgO) and a composite material containing MgO and natural minerals ('MgO-SH-A') as the soil amendments for suppression of cadmium (Cd) uptake and accumulation into rice grains. A cultivation experiment of rice plants (Oryza sativa L. cv. Kinuhikari) was conducted in an actual Cd-contaminated alluvial paddy field to evaluate the effectiveness of these materials. The 'plant available' fractions of Cd in the paddy soil significantly decreased by application of commercial MgO at 2250 kg ha(-1) or MgO-SH-A at 4500 kg ha(-1). These decreases would be primarily attributed to the increase in soil pH due to applications of the MgO materials because these soil Cd fractions were significantly negatively correlated with the soil pH. Even under a suppressive condition for Cd uptake by rice plants, i.e., continuous flooding of the paddy field around the heading stage, applications of these materials further reduced Cd concentration in brown rice as compared to that from the control. It was concluded that the two MgO materials examined would be effective in preventing Cd contamination of rice grains grown in Cd-polluted paddy fields. 相似文献
1000.
Hattori T 《Radiation protection dosimetry》2008,131(3):340-345
By using a probabilistic approach, the effects of the dose distribution of radiation due to man-made radioactive nuclides when added to those of natural background radiation have been studied. These results show that additional exposure to man-made radiation of up to 0.5 mSv y(-1) (as a dose constraint) would not significantly change the distribution of total public doses. Taking into consideration such probabilistic analysis and rationales of derivations of exemption and clearance levels, it can be concluded that the minimum dose constraint that requires optimisation in radiation protection, should be set to 0.1 mSv y(-1), which is one-order magnitude higher than 0.01 mSv y(-1), the current dose criterion for exemption and clearance. 相似文献