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71.
Ino T 《The Review of scientific instruments》2012,83(4):045101
A homogeneous magnetic field is essential for the (3)He neutron spin filter used to polarize neutron beams and analyze neutron spins in neutron scattering. The required spatial uniformity of the magnetic field is on the order of 10(-4)/cm or less. To measure such uniformity, one needs a DC current source with a current stability much better than 10(-4). However, laboratory DC power supplies, which are commonly used in many (3)He neutron spin filters, do not have such stabilities. To attain a highly stable current with a common laboratory DC power supply for every (3)He neutron spin filter, a simple feedback circuit has been developed to keep the output current stable up to 10(-6). Such a highly stable current or voltage from a common laboratory DC power supply can also be used for various other research applications. 相似文献
72.
Shibuya K Koshimizu M Asai K Muroya Y Katsumura Y Inadama N Yoshida E Nishikido F Yamaya T Murayama H 《The Review of scientific instruments》2007,78(8):083303
We introduce experimental systems which use accelerators to evaluate scintillation properties such as scintillation intensity, wavelength, and lifetime. A single crystal of good optical quality is often unavailable during early stages in the research and development (R&D) of new scintillator materials. Because of their beams' high excitation power and/or low penetration depth, accelerators facilitate estimation of the properties of early samples which may only be available as powders, thin films, and very small crystals. We constructed a scintillation spectrum measurement system that uses a Van de Graaff accelerator and an optical multichannel analyzer to estimate the relative scintillation intensity. In addition, we constructed a scintillation time profile measurement system that uses an electron linear accelerator and a femtosecond streak camera or a microchannel plate photomultiplier tube followed by a digital oscilloscope to determine the scintillation lifetimes. The time resolution is approximately 10 ps. The scintillation spectra or time profiles can be obtained in a significantly shorter acquisition time in comparison with that required by conventional measuring systems. The advantages of the systems described in this study can significantly promote the R&D of novel scintillator materials. 相似文献
73.
We proposed a strain mapping technique by Nano Beam electron Diffraction (NBD) combined with an energy filter (EF) and a scanning transmission electron microscopy (STEM) function. The STEM function improves the accuracy of a position where a diffraction pattern is acquired. The EF excludes inelastic scattering and enables novel numerical processing for the appropriate measurement of distances between diffraction disks. Using this technique, strain distributions were measured for two different types of p-MOSFETs, i.e., source/drain regions of each MOSFET is composed of different types of silicide, and the difference of their strain distributions in the channel region was confirmed. The proposed method was able to clarify that the strain distributions are quite different depending on the silicide materials even if the exterior of the MOSFETs was almost identical. 相似文献
74.
Yasunori Ino Wataru Kuriyama Osamu Ogata Takaji Matsumoto 《Topics in Catalysis》2010,53(15-18):1019-1024
A ruthenium complex was found to catalyze the hydrogenation of chiral esters without the loss of their optical purities under mild and neutral conditions. This method can avoid a violent quench step and an extraction step which accompany conventional reduction using metal hydride reagents such as sodium borohydride and lithium aluminum hydride. 相似文献
75.
Han Chen Fumihiko Kawaguchi Jingyuan Chen Toyohiko Nishiumi 《Electrochimica acta》2010,55(23):6959-6963
The reduction of the emeraldine form of polyaniline film into leucoemeraldine, which corresponds to the conversion of an electric conductor into an insulator, shifted in the positive direction with increasing scan rate and film thickness. Similar dependence was found in the diffusion-controlled voltammograms of dispersed polyaniline latex particles with eight diameters ranging from 0.2 to 7.5 μm. The particles were synthesized by coating dispersed polystyrene latex with polyaniline. These variations were explained in terms of electric percolation of the conducting species to the electrode. The theoretical expression for the Nernst equation was derived on the assumption that the percolated and the un-percolated conducting species took inner potentials of the electrode and the solution phase, respectively. The conducting species does not participate in the determination of the equilibrium potential, though it participates in the Faradaic current. The cathodic peak potential shifted in the negative direction with an increase in particle size, solution viscosity, and film thickness, as predicted from the derived Nernst equation. 相似文献
76.
77.
The aliphatic and polycyclic aromatic fractions of dust collected in the vicinity of recycled paper processing operations were analyzed using gas chromatography/mass spectrometry. Total measured dust concentration (up to 8.73+/-2.02 mg/m3) fluctuated substantially in the different steps of paper manufacture. This was attributed to the type of the operation such as, the release of fibers and particles during paper cutting and the use of reactive chemicals and excessive water under high temperature and pressure during the bleaching and the water rinsing/drying step. Particulate polycyclic aromatic hydrocarbons (PAHs) (from fluorene to benzo[ghi]perylene with mean concentrations from 3.8+/-0.5 to 41.4+/-0.4 ng/m3) and the unresolved mixture of branched, cyclic and unsaturated hydrocarbons (UCM) were measured in all samples while, n-alkanes from n-C20 to n-C27, were only observed in cutting and packaging areas (from 180.6+/-18.9 to 4297.9+/-794.9 ng/m3). The profile of occupational PAHs in bleaching and treatment of contaminated recycled raw paper was comparable to that observed for anthropogenic activities. The values of molecular diagnostic ratios indicated the contribution of oil residues and emissions from worklifts and other equipment used for pulp and paper handling. Total benzo[a]pyrene-equivalent (BaP) concentrations of particulate PAHs (varied from 323 up to 1104 pg/m3), provided evidence that workers were exposed to high quantities of PAHs as compared with exposures to urban air and other indoor settings, posing long-term threat to their health. 相似文献
78.
Tabata A Namba F Yamada M Hasegawa T Nakahira K Hamada D Kitajima H Fukusaki E Yanagihara I 《Journal of Bioscience and Bioengineering》2006,101(2):190-197
Annexin A2, a Ca2+-dependent phospholipid binding protein, is abundantly expressed in various human organs, which exists as either a membrane-associated, cytosolic or soluble form in serum. We constructed expression systems for recombinant human annexin A2 (rhA2) using Pichia pastoris. The systems are designed to secrete rhA2 as either the N- or C-terminally His6-tagged form to facilitate purification. Both types of rhA2 were overexpressed, but in the N-terminal-truncated form as revealed from the results of N-terminal amino acid sequencing and Western blotting. Therefore, further purification of N-terminally His6-tagged rhA2 was not feasible because of the removal of the N-terminal His6-tag sequence. C-terminally His6-tagged rhA2 was expressed as either a glycosylated or a nonglycosylated form, and the nonglycosylated form was purified using the combination of nickel-immobilized affinity, concanavalin A and cation exchanged column chromatographies. The solid-phase binding of rhA2 was examined by enzyme-linked immunosorbent assay (ELISA), which revealed the specific reactivity of rhA2 against an anti-annexin A2 monoclonal antibody. These results suggest that the expression system using P. pastoris is useful for the preparation of rhA2 that is applicable to the ELISA detection of the anti-annexin A2 antibody. 相似文献
79.
Yukiteru Ouji Masahide Yoshikawa Kei Moriya Mariko Nishiofuku Noriko Ouji-Sageshima Ryosuke Matsuda Fumihiko Nishimura Shigeaki Ishizaka 《Journal of Bioscience and Bioengineering》2010,110(4):487-490
A method for obtaining mouse hepatocytes by infusing collagenase solution into the left ventricle was established. This technique was shown to be equivalent to the intra-portal infusion method and more practical, especially in postnatal mice with a small body size. 相似文献
80.
Template matching is a method of searching for a target image area that is similar to a template image. However, the target image area generally must have the right position relative to the template image. Therefore, the computational cost is high when the location and the inclination of the target image area are unknown. This paper proposes a method of searching for a target image area with arbitrary location and an arbitrary inclination by means of geometrical parameters obtained by an equidistant edge group. In this method, the difference of directions is calculated from the edge direction of a referenced edge pixel and from the directions from the referenced edge pixel to other selected edge pixels. After that, matching is performed, using the difference in directions and the matching rates are accumulated. Then the location and inclination of the target image area are sought by scanning the accumulation space. Experimental results show that the proposed method has higher reliability and lower computational cost for image matching. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(1): 34–42, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20520 相似文献