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All-optical logic gates containing a two-mode nonlinear waveguide   总被引:1,自引:0,他引:1  
We propose a new element containing a two-mode nonlinear waveguide consisting of Kerr-like material for all-optical logic circuits. The proposed element, incorporated into the Mach-Zehnder interferometer, functions like a phase shifter. Although the optical waves propagating in the proposed element are monochromatic and identical in polarization, its function is insensitive to the relative phase difference between the incident beams. Using this element, we can realize various logic functions. In this paper, we demonstrate such logic circuits as inverters, distributors, and AND gates  相似文献   
35.
A prototype Mott transistor, the electric double layer transistor with a strained CaMnO(3) thin film, is fabricated. As predicted by the strain phase diagram of electron-doped manganite films, the device with the compressively strained CaMnO(3) exhibits an immense conductivity modulation upon applying a tiny gate voltage of 2 V.  相似文献   
36.
The development of advanced technology for the spent nuclear fuel reprocessing should be achieved not only considering cost, non proliferation and reduction of radioactive wastes but also corresponding to both spent nuclear fuels of LWR and FBR.

We have proposed an ion exchange process for reprocessing using a new type ion exchanger developed to chemical method of U enrichment technology. This process possess possibility of a sharp cut in cost, since this ion exchanger is characterized by rapid adsorption-desorption rate dominating the treatment rate.

From the basic experimental results, this reprocessing process has been constructed by 3 ion exchanger columns which consist of a main separation column, the uranium-refining column and the plutonium-refining column.

Comparing ion exchange process with the conventional Purex process, this ion exchange process has many advantages such as the decrease in the number and size separation equipment, solvent-spent free and alkaline-liquid-spent free. With these advantages, this process is estimated that the construction cost of reprocessing process is greatly reduced comparing to the conventional process.  相似文献   

37.
Cyclooxygenase (COX)-2 is induced by proinflammatory cytokines such as interleukin (IL)-1 beta, cytokines produced from helper T cell subpopulation Th 1, such as interferon-gamma and tumor necrosis factor-beta. Cytokines produced by the T cell such as IL-4, IL-10, and IL-13 down-regulate induction of COX-2. The novel MAP kinase pathway, JNK and/or p 38, are important intracellular signaling pathways for induction of COX-2. The increased production of prostaglandin E2 by upregulation of COX-2 increases IL-6 production. By utilizing a COX-2 blocker, it is possible to decrease IL-6 production via reduction of prostanoid production, thereby attenuating the systemic inflammatory response. Nitric oxide (NO) and prostanoids are also known to interact and regulate each other. It is important to note the interactions between prostanoids and cytokines or other inflammatory mediators such as NO in understanding the mechanism of the anti-inflammatory effects of prostanoid regulation.  相似文献   
38.
MED-L cells with the 75 kd low-affinity nerve growth factor receptor (p75NGFR) and MED-H cells with the proto-oncogene tropomyosin receptor kinase product (p140trk) were isolated selectively from a parent MED-3 cell line derived from cerebellar medulloblastoma by panning, and the interaction of nerve growth factor (NGF) with these cell lines was analyzed. NGF treatment induced neuronal differentiation, growth inhibition, and tyrosine phosphorylation of p140trk in MED-H cells, but not in MED-L cells. Medulloblastoma cells express the functional NGFR, p140trk, which regulates their differentiation and growth.  相似文献   
39.
The purpose of this study was to investigate the availability of an orthotopic transplantation of partial hepatic autograft in dogs as a means of surgical training. Male mongrel dogs weighting 10-15 kg were used. The left lobe of the liver was harvested while preserving the left branches of the portal vein, hepatic artery and bile duct, and the left hepatic vein. The remnant liver was removed while preserving the inferior vena cava using a veno-venous bypass. Orthotopic transplantation of the autograft was performed while anastomosing the left hepatic vein to the inferior vena cava, portal and arterial reconstruction, and external biliary drainage. Thirteen out of 29 dogs survived more than 48 h after transplantation. However, 6 out of 13 dogs were sacrificed after developing bile peritonitis due to a dislodgement of the biliary catheter, and only two dogs were able to survive for 7 days after transplantation. The arterial ketone body ratio recovered to 1.0 within 1 h after reperfusion, and the ratio of the dogs that survived for more than 48 h remained above 1.0 until sacrifice. Orthotopic transplantation of a partial hepatic autograft is a useful and simple procedure to train surgeons for partial liver transplantation.  相似文献   
40.
This paper considers a standby-redundant system consisting of 2 systems, in which one is main and the other is its standby-redundant system. These systems also consist of 2 subsystems connected in series.A feature of this system is that the system has 2 switching devices connecting subsystems, in addition to one connecting main and standby systems, in order to utilize surviving subsystem. In this consideration it is assumed that all the units are repairable.We shall obtain the system reliability, the mean time to system failure, the steady state availability, and examine numerically the effects of this model to the usual one without particular switching devices.  相似文献   
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