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排序方式: 共有1750条查询结果,搜索用时 265 毫秒
41.
Yuichiro Ezoe Ikuyuki Mitsuishi Utako Takagi Masaki Koshiishi Kazuhisa Mitsuda Noriko Y. Yamasaki Takaya Ohashi Fumiki Kato Susumu Sugiyama Raul E. Riveros Hitomi Yamaguchi Shinya Fujihira Yoshiaki Kanamori Kohei Morishita Kazuo Nakajima Ryutaro Maeda 《Microsystem Technologies》2010,16(8-9):1633-1641
We are developing novel ultra light-weight and high-resolution X-ray micro pore optics for space X-ray telescopes. In our method, curvilinear micro pore structures are firstly fabricated by silicon deep reactive ion etching (DRIE) or X-ray LIGA processes. Secondly, side walls of the micro structures are smoothed by magnetic field assisted finishing and/or hydrogen annealing techniques for high reflectivity mirrors. Thirdly, to focus parallel X-ray lights from astronomical objects, these structures are elastically or plastically bent into a spherical shape. Fourthly, the bent structures are stacked to form a multi-stage X-ray telescope. In this paper, we report on fabrication and X-ray reflection tests of silicon and nickel X-ray mirrors using the DRIE and LIGA processes, respectively. For the first time, X-ray reflections were confirmed on both of the mirrors. Estimated rms roughnesses were 5 nm and 3 nm for the silicon and nickel mirrors, respectively. 相似文献
42.
Shiro Kumano Kazuhiro Otsuka Junji Yamato Eisaku Maeda Yoichi Sato 《International Journal of Computer Vision》2009,83(2):178-194
In this paper, we propose a method for pose-invariant facial expression recognition from monocular video sequences. The advantage
of our method is that, unlike existing methods, our method uses a simple model, called the variable-intensity template, for
describing different facial expressions. This makes it possible to prepare a model for each person with very little time and
effort. Variable-intensity templates describe how the intensities of multiple points, defined in the vicinity of facial parts,
vary with different facial expressions. By using this model in the framework of a particle filter, our method is capable of
estimating facial poses and expressions simultaneously. Experiments demonstrate the effectiveness of our method. A recognition
rate of over 90% is achieved for all facial orientations, horizontal, vertical, and in-plane, in the range of ±40 degrees,
±20 degrees, and ±40 degrees from the frontal view, respectively.
Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users. 相似文献
43.
Straight-through microchannel devices for generating monodisperse emulsion droplets several microns in size 总被引:1,自引:1,他引:0
Isao Kobayashi Takayuki Takano Ryutaro Maeda Yoshihiro Wada Kunihiko Uemura Mitsutoshi Nakajima 《Microfluidics and nanofluidics》2008,4(3):167-177
The authors recently proposed a promising technique for producing monodisperse emulsions using a straight-through microchannel
(MC) device composed of an array of microfabricated oblong holes. This research developed new straight-through MC devices
with tens of thousands of oblong channels of several microns in size on a silicon-on-insulator plate, and investigated the
emulsification characteristics using the microfabricated straight-through MC devices. Monodisperse oil-in-water (O/W) and
W/O emulsions with average droplet diameters of 4.4–9.8 μm and coefficients of variation of less than 6% were stably produced
using surface-treated straight-through MC devices that included uniformly sized oblong channels with equivalent diameters
of 1.7–5.4 μm. The droplet size of the resultant emulsions depended greatly on the size of the preceding oblong channels.
The emulsification process using the straight-through MC devices developed in this research had very high apparent energy
efficiencies of 47–60%, defined as (actual energy input applied to droplet generation/theoretical minimum energy input necessary
for making droplets) × 100. Straight-through MC devices with numerous oblong microfluidic channels also have great potential
for increasing the productivity of monodisperse fine emulsions. 相似文献
44.
Inhomogeneities in semiconductor solids can be imaged by two-dimensional mapping of the amplitude of periodically modulated tip current in scanning tunneling microscopy that is induced by illumination of semiconductor samples with a chopped light. It has been shown that it is possible to distinguish between plural origins of the photo-modulated current by analyzing the response properties of the current signal. A judicial choice of the modulation frequency is important for the required contrasts to be obtained. 相似文献
45.
Kazuaki Mita Shu Yamaguchi Masafumi Maeda 《Metallurgical and Materials Transactions B》2004,35(3):487-492
Most galvanized steel sheets are produced by a continuous galvanizing line. Some of the operations include a subsequent heat
treatment termed galvannealing to form intermetallic phases on the surface. These galvanizing reactions are essentially regarded
as “making intermetallic compounds” in the Fe-Zn-M system. This makes it important to know the thermodynamic properties of
the system for any detailed discussion on the formation of these intermetallics; however, experimental difficulties have limited
the number of studies. In the present study, two-phase regions of these intermetallics were examined, and the following two-phase
mixtures were prepared at 723 K: Fe(α)+Γ, Γ,+Γ1, Γ1+δ
1+ζ. The double cell-type Knudsen mass spectrometer system was developed and employed, in which two sets of Knudsen cells were
installed in the same cell holder. The reference material (pure zinc) was placed in one cell and a sample in the other. The
cell holder was rotated to the reference and sample positions to measure zinc vapor effused from two cells by a quadrupole
mass spectrometer. Material containing the two phases was placed in a Knudsen-type effusion cell and the mass spectrum studied
to evaluate the vapor pressure of zinc. The activity of zinc in the intermetallics was determined by comparing the intensity
from pure zinc and that from intermetallics. Results for Fe(α)+Γ were 0.46 to 0.48; for Γ+Γ1, 0.51 to 0.54; for Γ1+δ
1, 0.62 to 0.66; and for δ
1+ζ, 0.80 to 0.83, between the temperatures of 623 and 698 K. 相似文献
46.
Kaneko D. Maeda T. Ito T. Ohki Y. Konishi T. Nakamichi Y. Okashita M. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2004,11(4):708-714
Effects of superposition of a low-frequency (0.1 to 50 Hz) voltage and a high-frequency 2 kHz voltage on the growth of water trees in polyethylene are examined. It has become clear that both the number of total voltage zero-crossings during the whole voltage application period and the number of consecutive voltage zero-crossings in the instant of the polarity reversal of the low-frequency voltage play important roles in the length and shape of water trees. Namely, the water tree length becomes longer as the number of total zero-crossings increases. Furthermore, among the voltages with the same number of total zero-crossings, the length becomes even longer with a prolonged shape in the direction of electric field as the number of consecutive zero-crossings increases. Effects of superposition of a high-frequency voltage onto a dc voltage are also examined. In this case, the dc voltage seems not to have any influence to the tree growth. By assuming the presence of space charge around the water-tree tip, the effective zero-crossings become only sensitive to the high-frequency component. Therefore, this result also indicates that the number of voltage reversals at the tree tip plays a crucial role in the growth of water trees. 相似文献
47.
H. Furuta Y. FukudaT. Hara T. Haruna N. IshiharaM. Ishitsuka C. ItoM. Katsumata T. KawasakiT. Konno M. KuzeJ. Maeda T. MatsubaraH. Miyata Y. NagasakaK. Nitta Y. SakamotoF. Suekane T. SumiyoshiH. Tabata M. TakamatsuN. Tamura 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2012,662(1):90-100
We carried out a study of neutrino detection at the experimental fast reactor JOYO using a 0.76 tons gadolinium loaded liquid scintillator detector. The detector was set up on the ground level at 24.3 m from the JOYO reactor core of 140 MW thermal power. The measured neutrino event rate from reactor on-off comparison was 1.11±1.24(stat.)±0.46(syst.) events/day. Although the statistical significance of the measurement was not enough, backgrounds in such a compact detector at the ground level were studied in detail and MC simulations were found to describe the data well. A study for improvement of the detector for future such experiments is also shown. 相似文献
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