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1.
A novel tungsten light-shield structure has been developed. Tungsten film properties, the device configuration with the tungsten light-shield structure, and experimentally achieved results regarding device characteristics are described. Optical measurement clarified that tungsten film has a sufficiently low transmittance value for practical use for more than 200-nm-thick film and is stable up to 1000°C. The good step coverage and low reflectance, such as 20-40% for aluminum, required for light-shield film were also obtained. A tungsten light-shield structure was applied to a 1/2-in format 668(H)-pixel×575(V)-pixel charge coupled-device (CCD) image sensor. An extremely low smear value, less than 0.001%, was obtained for a 300-nm film thickness  相似文献   
2.
This paper describes a novel method to measure the loci and attitudes of a high-speed moving object in a three-dimensional space. Here, the method to the golf driver head is applied. The employed sensor is a line-charge-coupled device (CCD) camera with a high-speed scanning. Because the camera captures only one-dimensional (line) information in a two-dimensional image, the scanning speed is very high. During a measurement, the line-CCD camera captures the positions of markers located on the driver head. Simple signal processing yields the position at every scan interval and estimates the loci and attitudes of the golf club head. Here, the method to the golf head motion measurement is applied: However, it can be applied to a variety of high-speed moving objects other than a driver head  相似文献   
3.
Complementary DNAs encoding three human isoforms (neuronal, inducible, and endothelial) of nitric oxide synthase were cloned into the baculovirus expression vector pVL1392/1393. Transfection of Sf-9 insect cells with the recombinant baculovirus resulted in the expression of high levels of nitric oxide synthases. The expressed proteins of neuronal and inducible nitric oxide synthase were predominantly soluble, whereas the endothelial enzyme was for the most part, particulate. Recombinant enzymes were purified with 2',5'-ADP Sepharose affinity chromatography. The effects of reference enzymatic inhibitors (NG-methyl-L-arginine, NG-nitro-L-arginine and N-iminoethyl-L-ornithine) on recombinant expressed proteins were not significantly different from native nitric oxide synthase enzyme preparations. L-aminoguanidine was found to be much less potent in inhibiting recombinant or native human inducible nitric oxide synthase compared to the murine isoform. These findings indicate previously unappreciated interspecies differences in the action of nitric oxide synthase enzymatic inhibitors. The functional expression of human nitric oxide synthase isoforms in a heterologous expression system allowed screening of novel inhibitors. Studies indicated that S-ethylisothiourea and 2-amino-5,6-dihydro-6-methyl-4H-1,3-thiazine were potent novel inhibitors of human nitric oxide synthases.  相似文献   
4.
A 1-inch 2-million pixel FIT-CCD image sensor for HDTV has been developed, which features a tungsten photo-shield and horizontal CCD (H-CCD) shunt wiring. Tungsten photo-shield, which has low reflectance and good step coverage characteristics, reduces smear level to -110 dB, combined with a frame-interline-transfer (FIT) scheme. The tungsten photo-shield also acts as a shunt busline, supplying transfer pulses to vertical CCD (V-CCD) electrodes, so that a 1.2×10ˆ5 electron charge handling capability is obtained at a frame transfer frequency of 1 MHz. Newly developed H-CCD shunt wiring suppresses vertical line pair FPN, even with smaller transfer pulse amplitudes. H-CCD shunt wiring also helps reduce power consumption in the H-CCD by 2/3 as compared to that achieved with conventional wiring  相似文献   
5.
Gut-associated lymphoid tissue is the major inductive site of the mucosal immune system, which is functionally independent of the systemic immune system. Both the amount and type of dietary fat modulate intestinal immune function. Absorption of long-chain fatty acids stimulates lymphocyte flux and lymphocyte blastogenesis in intestinal lymphatics. Long-chain fatty acid absorption also significantly enhances migration of T lymphocytes to Peyer's patches, possibly due to up-regulation of adhesion molecules, such as alpha4-integrin and L-selectin. Lipoproteins are involved in stimulation of lymphocyte function by both receptor-dependent and independent mechanisms. However, unsaturated fatty acids at higher concentrations have a suppressive effect on cell-mediated immunity via eicosanoid release, receptor affinity changes or interactions with intracellular signal transduction. Fat absorption also influences various other cells in the intestinal mucosa: increased cytokine release from intestinal epithelial cells follows long-chain fatty acid absorption. In Crohn's disease, elemental diets and total parenteral nutrition often induce remission, possibly by reducing antigenic load on activated immune cells in the intestine and, thus, down-regulating hyperreactive CD4 cells. Dietary oleic acid supplements caused an immunological reversal effect in the intestinal immune system of animals fed an elemental diet. An excess of long-chain fatty acids in an elemental diet, therefore, may negate its beneficial effect on gut-associated lymphoid tissues in Crohn's disease. In contrast, supplemental dietary fish oil apparently tends to prevent relapse of Crohn's disease. Because dietary fat intake is closely associated with immunological function of the intestinal mucosa, careful manipulation of dietary fat can be important in management of this disease.  相似文献   
6.
Abstract

Repeated application of buckminsterfullerene (C60) toluene solution combined with ultraviolet A (UVA) radiation onto hairless mouse back skin resulted in enhancing formation of erythema as an acute disease but induced no carcinoma on the skin. This result is probably due to insolubility of C60 in the living cells to generate little singlet oxygen 1O2 by UVA radiation.  相似文献   
7.
A 30 frames/s 2/3-in 1.3 M-pixel progressive scan interline-transfer charge-coupled device (IT-CCD) image sensor has been developed for video and digital still-camera applications. To obtain high frame-rate images, a 49-MHz driving horizontal CCD (H-CCD) was developed. An 8-phase drive for vertical CCDs (V-CCDs) makes it possible to operate in a variety of modes, such as 1050 line progressive scan mode and 1049 line wide dynamic range interlaced scan mode. For digital still camera use, removing residual charges stored in the V-CCDs before exposure is essential, therefore new narrow-channel barrier over-flow drain (NCB-OFD) attached under the H-CCD was developed. The NCB-OFD automatically drains out extra charges and has the advantages of requiring neither an over-flow control gate nor any additional masks  相似文献   
8.
This paper presents a method to control the stereo stage width to provide additional functionality to a stereophonic sound-field recording/reproduction system that uses two microphones and two loudspeakers. The proposed method interpolates or extrapolates the time-frequency representations of the left and right stereo signals according to the desired scaling magnification. A mathematical analysis is introduced that clarifies the scaling ability of the proposed method. Listening tests using a stereo signal consisting of a mixture of two speech signals with different time-lags are performed. The results indicate that the two stereo signals yield almost the same aural impression when the scaling magnification is under two and the following two requirements are satisfied. 1) The time-lags in the stereo signal are scaled strictly before mixing. 2) The time-lags are scaled approximately by the proposed method after mixing. The listening tests also clarified the superiority of the proposed method in terms of the sound quality with respect to conventional methods.  相似文献   
9.
We have determined the practical limits of cell size reduction in interline-transfer charge-coupled device (IT-CCD) image sensors, which result from diffraction occurring at the aperture above the photodiode. We have found that image cell size cannot be reduced to a level for which aperture width would fall below about 0.2 μm. We have also found, however that image cells with greater than 0.2 μm aperture size are sensitive over the entire wavelength range of visible light, and that sensitivity can be increased by thinning the photoshield film  相似文献   
10.
A newly developed 1/4-inch 380 k pixel IT-CCD image sensor features a novel cell structure in which signal charges are read out from a photodiode (PD) to a vertical-CCD (V-CCD) in a gate-assisted punchthrough mode. The cell structure, fabricated through the use of high energy ion implantation technology, enables both deep PD formation and transfer-gate (TG)/channel-stop (CS) length reduction. Deep PD formation helps increase sensitivity per PD unit area, and TG/CS length reduction widens both PD and V-CCD areas. Although the cell size is small (4.8 /spl mu/m (H)/spl times/5.6 /spl mu/m (V)), the sensor achieves both high sensitivity (35 mV/lx) and a high saturation signal (600 mV).<>  相似文献   
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