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151.
152.
153.
Electron spectroscopy for chemical analysis (ESCA) and Fourier-transform infrared (FT-IR) attenuated total reflection (ATR) studies have been made on the film of blend polymers consisting of poly(hydroxypropyl ether) of bisphenol A (P) and poly(ethylene oxide) (E) or P and poly(ethylene adipate) (A) formed on nylon-6 (Ny) substrate to investigate the boundary-phase structure between the substrate and the polymer blends. For the case of P/A blend, A is enriched to the depths probed by both ESCA (below ca. 60 Å) and FT-IR-ATR (below ca. 0.7 μm) from the nylon-6 surface. For the P/E blend, though P is enriched to the depth probed by ESCA from the Ny surface, the enrichment of neither of the blend components can be found to the depth probed by FT-IR-ATR. These results indicate the different susceptibility between P/A and P/E blends to the influence from the Ny substrate. 相似文献
154.
Shigeru Sugiyama Kohji Satomi Naoya Shigemoto Hiromu Hayashi John B. Moffat 《Catalysis Letters》1994,25(3-4):201-208
The oxidative coupling of methane on magnesium oxide (MgO) has been studied in the presence of carbon tetrachloride (TCM) as a gas-phase additive. Addition of a small amount of TCM to the reactant stream improves the selectivity to C2H4, while the conversion of methane is not influenced by the additive. X-ray photoelectron spectra of the used MgO reveal the formation of chlorine species on the catalyst surface in quantities up to 0.20 of Cl/Mg (atomic ratio), although X-ray diffraction spectra of the catalyst show MgO only and the content of the chlorine species in the bulk phase estimated by X-ray fluorescence analysis is very low. It is concluded that the enhancement of the selectivity to C2H4 primarily results from the presence of surface chlorine species. The chlorinated species on the catalyst has been identified as MgCl2. 相似文献
155.
Koji Maeda Shinji Sasaki Misaki Kumai Isamu Sato Mitsuo Suto Masahiko Ohsaka 《Journal of Nuclear Science and Technology》2014,51(7-8):1006-1023
Since the start of the severe accidents at the Fukushima Daiichi Nuclear Power Plant in March 2011, concrete surfaces within the reactor buildings (RBs) have been exposed to radioactive contaminants. Released radionuclides still remain too high to permit entry into some areas of the RBs to allow the damage to be assessed and to allow carrying out the restoration of lost safety functions, decommissioning activities, etc. In order to clarify the situation of this contamination in the RBs of Units 1, 2 and 3, samples of contaminants were collected and subjected to analyses to determine the surface radionuclide concentrations and to characterize the radionuclide distributions in the samples. Especially, decontamination tests on the boring core sample of Unit 2 were conducted to quantitatively determine the effectiveness of several basic decontamination techniques. As a result of the tests, the level of radioactivity of this sample was reduced with the removal of ~97% of the contamination present near the sample surface, and it was confirmed for the boring core sample that the contamination mainly had the characteristics of fixed contamination of the surface. 相似文献
156.
Yoshinori Tatematsu Yuusuke Yamaguchi Toshitaka Idehara Takanori Ozeki Ryosuke Ikeda Tomohiro Kanemaki Isamu Ogawa Teruo Saito 《Journal of Infrared, Millimeter and Terahertz Waves》2012,33(3):292-305
Development of gyrotrons with an internal mode convertor has started in Research Center for Development of Far-Infrared Region,
University of Fukui (FIR FU). As the first gyrotron of such a kind, we have designed and manufactured Gyrotron FU CW GI. It
operates at 203 GHz at fundamental cyclotron resonance. We have designed a cavity and a mode convertor under some constraints
such as reuse of an electron gun and small diameter of a magnet bore. Designed output power is about 1 kW. We have succeeded
in observation of a circular radiation pattern. The maximum observed output power is 0.5 kW for the setting cathode voltage
of 20 kV and the beam current of 0.5 A. This success makes gyrotron development in FIR FU to proceed to a new stage. 相似文献
157.
Toshitaka Idehara Jagadish C. Mudiganti La Agusu Tomohiro Kanemaki Isamu Ogawa Toshimichi Fujiwara Yoh Matsuki Keisuke Ueda 《Journal of Infrared, Millimeter and Terahertz Waves》2012,33(7):724-744
For application of high frequency gyrotron to high power THz technology, Gyrotron FU CW series is being developed in FIR FU.
Gyrotron FU CW CI is developed as one of sub-THz gyrotrons included in the series. The advantage of the gyrotron is compactness
using a compact superconducting magnet and compact power supply system, which makes the accesses of the gyrotron to applied
large-scale devices easier and extends the applications of gyrotron to wider fields. The designed frequency and cavity mode
are 394.5 GHz and TE26 mode for application to the 600 MHz DNP-NMR spectroscopy. As the operation results, the frequency and the output power were
394.03 GHz and around 30 W, respectively, which are available for the application to the 600 MHz DNP-NMR measurement. In addition,
this gyrotron can operate at many other frequencies and cavity modes for application to high power THz technologies in wide
fields. In this paper, the design and the operation results including long pulse or CW mode are presented. 相似文献
158.
Yoh Matsuki Keisuke Ueda Toshitaka Idehara Ryosuke Ikeda Kosuke Kosuga Isamu Ogawa Shinji Nakamura Mitsuru Toda Takahiro Anai Toshimichi Fujiwara 《Journal of Infrared, Millimeter and Terahertz Waves》2012,33(7):745-755
In this paper we present results that demonstrate the utility of a continuously frequency-tunable 0.4 THz-gyrotron in a dynamic
nuclear polarization (DNP)-enhanced solid-state NMR (SSNMR) spectroscopy at one of the highest magnetic fields, B
0 = 14.1 T (600 MHz for 1H Larmor frequency). Our gyrotron called FU CW VI generates sub-mm wave at a frequency near 0.4 THz with an output power of
4–25 W and a tunability over a range of more than 1 GHz by sweeping the magnetic field at the gyrotron cavity. We observed
overall down shifting of the central frequency by up to ~1 GHz at high radiation duty factors and beam current, presumably
due to the cavity thermal expansion by a heating, but the tunable range was not significantly changed. The frequency tunability
facilitated the optimization of the DNP resonance condition without time-consuming field-sweep of the high-resolution NMR
magnet, and enabled us to observe substantial enhancement of the SSNMR signal (ε
DNP = 12 at 90 K). 相似文献
159.
Hiroshi Akie Isamu Sato Motoe Suzuki Hiroyuki Serizawa Yasuo Arai 《Journal of Nuclear Science and Technology》2013,50(1):107-121
A simple formula is developed for the evaluation of the helium production amount in fast reactor minor actinide (MA) containing uranium–plutonium mixed oxide (MOX) fuel. For the subroutine use in the existing fuel behavior analysis code, the formula is designed putting emphasis on simplicity and quickness rather than accuracy. The accuracy of the formula is confirmed by comparing with the detailed calculation with SWAT code, and also with the post irradiation examination (PIE) results of the fuel pin irradiated at the experimental fast reactor JOYO. As a result, it is found that the formula evaluates the helium production amount with the difference of less than about 10% from the detailed calculation and the PIE results, when the MA isotope content is less than 5 wt.%. Based on these results, the formula is installed in the fuel behavior analysis code for the simulation of helium behavior in fast reactor fuels. 相似文献
160.
For the purpose of enhancing the reinforcement–matrix interaction in carbon-fiber-reinforced polymer composite, mechanical and spectroscopic studies were made on the epoxy resin composite reinforced with the carbon fiber coated with thin Layer of polyimide resin. On the loss modulus and loss tangent vs. temperature curves, a subtransition appears at a temperature above the primary transition. The T-peel strength of a laminated specimen and the fiber efficiency factors for modulus and strength are larger than those of the composite reinforced with nonpolyimide treated fiber. These results show the increased interaction between the epoxy resin and the carbon fiber coated with polyimide resin. The occurrence of specific interaction between an epoxy resin and the polyimide resin are recognized on fourier transform infrared spectra. 相似文献