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1.
The authors report a rare case of a large cystic cervical neurinoma. A 45-year-old female was admitted to our clinic because of motor weakness of the right upper extremity, numbness of the right fingers and right posterior cervical pain. Metrizamide CT myelography demonstrated the outline of a low density mass. MRI showed a mass revealing low signal intensity on T1-weighted image, high signal intensity on T2-weighted image and marginal enhancement on contrast image with Gd-DTPA. The mass which was diagnosed as cystic tumor, was located in the intradural extramedullary space between C4 to C5 segments. After C4 through C5 laminectomy, the tumor was found to originate from the C5 anterior motor root. The tumor consisted mostly of a cystic part with a very thin solid compartment beneath the capsule. Postoperative course of the patient was uneventful. Although spinal neurinoma is one of the most common spinal tumors, an almost completely degenerated large cystic spinal neurinoma is extremely rare. MRI with Gd-DTPA was useful for the diagnosis of the cystic neurinoma by clearly enhancing the margin of the tumor.  相似文献   
2.
Crystals of yttria partially stabilized zirconia were grown by the arc-image floating-zone technique and studied by transmission electron microscopy. Crystals annealed at 1700°C consist of tetragonal precipitates and a cubic matrix. The platelike domains in a precipitate are twin-related tetragonal variants stacked alternately parallel to the (011) twin plane. The axial relations between the tetragonal precipitate and the cubic matrix are [100]tetragonal|[100]cubic, [011]tetragonal|[011]cubic.  相似文献   
3.
Summary The synthesis of poly(-thiophenediyl)benzylidene (PTB) with high molecular weight is described. Number-average degrees of polymerization reached about 74. The characterizations of the polymer was investigated by 1H-NMR, 13C-NMR, IR, and UV-VIS spectra. The polymer with well-defined structure and high molecular weight was obtained by polymerization at low temperature and in polar solvent. This polymer was thermally stable and a thermal decomposition took place at 391°C under nitrogen and at 370°C under air. The glass transformation temperature was 117°C and this PTB was nonfusible.  相似文献   
4.
Very uniform and transparent zinc oxide thin films doped with aluminium and indium were fabricated by the dip-coating technique using solutions prepared by the ethanolamine method. As starting materials, zinc acetate and zinc n-propoxide were used. Zinc acetate and propoxide are soluble in PriOH in the presence of diethanolamine, although they are hardly soluble without the amine. The prepared solutions were very stable and suitable for dip-coating. Zinc oxide was crystallized by heating above 500 °C, and doping of aluminium and indium retarded the crystallization. The electrical resistivity of the film was decreased by doping with aluminium and indium. The lowest resistivity of 2 × 10–2 cm was obtained by post-coating treatment in a nitrogen atmosphere.  相似文献   
5.
We propose a novel sequence alignment algorithm for recognizing handwriting gestures by a camera. In the proposed method, an input image sequence is aligned to the reference sequences by phase-synchronization of analytic signals which are transformed from original feature values. A cumulative distance is calculated simultaneously with the alignment process, and then used for the classification. A major benefit of this method is that over-fitting to sequences of incorrect categories is restricted. The proposed method exhibited higher recognition accuracy in handwriting gesture recognition, compared with the conventional dynamic time warping method which explores optimal alignment results for all categories.  相似文献   
6.
D-arabitol was first prepared from D-glucose using Candida famata R28. The reaction gave 5.0% D-arabitol from 10.0% D-glucose. D-arabitol was then almost completely converted to D-xylulose using Acetobacter aceti IFO 3281. Finally, D-lyxose was prepared from D-xylulose enzymatically using L-ribose isomerase from toluene-treated cells of Acinetobacter sp. strain DL-28. The isomerization reaction progressed steadily and the concentration of D-xylulose increased from 1.0 to 10.0%. About 70% of D-xylulose was converted to D-lyxose in all cases. Separation of residual D-xylulose from the reaction mixture is very difficult to achieve by column chromatography, but D-xylulose could be selectively degraded easily using Saccharomyces cerevisiae IFO 0841. The product was crystallized and was confirmed to be D-lyxose by HPLC, 13C-NMR spectra, IR spectra analysis, and optical rotation measurement.  相似文献   
7.
8.
Abstract— The Xe excitation efficiency for various Xe content was analyzed by monitoring the panel luminance and IR emission intensity. It was found that dependences of the Xe excitation efficiency and luminous efficacy on the sustain voltage show almost the same tendency. A decrease for increasing sustaining voltage was found in a low‐Xe‐content panel and an increase was found in a high‐Xe‐content panel. A reduction in the effective electron temperature and a reduction in plasma saturation contribute to the efficacy improvement. The time‐averaged spatial profile of the Xe excitation efficiency in PDPs was investigated by measuring the distribution of IR and blue‐phosphor emissions. The results show that the Xe excitation efficiency is similar in the cathode and anode regions even though the spatial and time development of the discharge in these regions is very different. An extended theory that takes into account not only the radiative transition process but also the collisional de‐excitation process from Xe** to Xe* is proposed for investigating the pressure dependence of the Xe excitation efficiency. By using the proposed theory, it was found that Xe excitation efficiency increases, attains a maximum value at 30% Xe, then decreases as the Xe content is increased, when the rate coefficient of the collisional de‐excitation process is less than 1.0 × 10?10 cm3/sec.  相似文献   
9.
Abstract— High‐Xe‐content PDPs attain improved luminous efficiency, but with sacrifices of higher sustain and address voltages and slower discharge build‐up. By examining PDPs with 3.5–100% Xe contents, it was revealed that space‐charge priming as well as wall‐charge accumulation are effective in obtaining low‐voltage and high‐speed operation. In addition, it was found that the effectiveness is emphasized for higher‐Xe‐pressure PDPs. In this respect, erase addressing is more favorable than write addressing, especially for high‐Xe‐pressure PDPs. The formative time lag of the discharge and diffusion/drift of the space charges are shorter for high Xe contents. In this respect, high‐Xe‐content PDPs have a potential for high‐speed addressing, if driven adequately. The use of space‐charge priming, however, is limited by the duration between the priming and scan pulses. Accumulation of wall charges is limited by ignition of a self‐erase discharge with which all the wall charges are dissipated. Although the highest efficiency and luminance are attained with a 100%‐Xe panel, the optimum Xe gas content, considering the sustain pulse voltage and drive voltage margin, would be 70% Xe + Ne.  相似文献   
10.
Abstract— The luminance of a backlight unit for an LCD TV is adaptively and locally dimmed along with the input video signal in order to reduce the power consumption and also to improve the picture quality. By adopting the zero‐dimensional (0D), 1D, and 2D adaptive dimming techniques, a sample movie having 8.0% post‐gamma average picture levels (APL) could be displayed using 83%, 71%, and 50% of the original backlight power, respectively. For an adoption of the 2D dimming, an LED backlight is preferable. The adaptive‐dimming technique also allows the differential aging characteristics between the LED components and temperature dependence of color and luminance to be overcome. From simulations of a reduction in power consumption, it was found that 40 × 40 pixels is a unit of the local dimming, 30 frames for the sampling period, 24 dimming steps, and an equal‐signal‐step method for determining the dimming factor have been found to be appropriate. The gray‐scale capability of low‐luminance images can also be improved by dimming the backlight luminance and expanding the input signal. By using an LCD TV having an 8‐bit capability, an 11‐bit‐equivalent gray‐scale expression was experimentally proven.  相似文献   
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