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951.
A high-pressure technique was adopted to obtain perovskite-type Pb(Li14Nb34)O3. A new perovskite Pb(Li14Nb34)O3 was characterized to have a cubic symmetry with ao = 4.069A?; Li and Nb ions in the B-site of perovskite lattice may be in a random arrangement.  相似文献   
952.
A 1-Mb BiCMOS DRAM having a 23-ns access time is described. The DRAM uses a direct sensing technique and a nonaddress-multiplexing configuration. This technique combines the NMOS differential circuit on each pair of data lines with a common highly sensitive bipolar circuit. The resulting chip has been verified to have high-speed characteristics while maintaining a wide operating margin and a relatively small chip size of 62.2 mm2, in spite of a 1.3-μm lithography level  相似文献   
953.
Unknown peaks were detected in the chromatogram of garland chrysanthemum extract in analysis of organophosphorus pesticide residues. The unknown peaks were identified as isomers of tricresyl phosphate (TCP) by GC/MS. TCP is used as a plasticizer in polyvinyl chloride, and there is no report of its detection in foods. Therefore, we investigated the origin of TCP detected in garland chrysanthemum. We found no effect of contact with packaging film or polyvinyl chloride sheet used in greenhouses. However, TCP was detected at 0.03 microg/g (average) in 16 of 20 samples of garland chrysanthemum that had been in contact with polyvinyl chloride tubing used for warming greenhouses. These results indicate that TCP migrated to the garland chrysanthemum from the tubing used to keep greenhouses warm.  相似文献   
954.
Photodynamic therapy (PDT) for exudative age-related macular degeneration (AMD) was evaluated using a supramolecular nanomedical device, that is, a novel dendritic photosensitizer (DP) encapsulated by a polymeric micelle formulation. The characteristic dendritic structure of the DP prevents aggregation of its core sensitizer, thereby inducing a highly effective photochemical reaction. With its highly selective accumulation on choroidal neovascularization (CNV) lesions, this treatment resulted in a remarkably efficacious CNV occlusion with minimal unfavorable phototoxicity.  相似文献   
955.
By utilizing the laser induced pressure-pulse (LIPP) technique, the behavior of space charge in low-density polyethylene (LDPE) and crosslinked polyethylene (XLPE) films in contact with metal or carbon-loaded semiconducting layers was studied quantitatively to clarify the space-charge characteristics in power cables. Negative heterospace charge near the anode and positive space charge in the bulk were observed in unoxidized LDPE under the fields above 120 kV/mm. The amount of negative space charge increased with applied field, while positive space charge in the bulk disappeared with increasing applied field. This indicates that electron injection and ionization are enhanced by applied field. Prominent negative homospace charge was formed near the cathode in oxidized LDPE, which indicates that oxidation enhanced electron injection. The depth of charge centroid from the cathode became larger with increasing temperature. This indicates that the effective electron mobility increases with temperature. Negative space charge also was formed in the bulk in XLPE films with metal electrodes, which indicates that crosslinking enhanced electron injection. XLPE films with a carbon-loaded semiconducting layer showed both negative and positive homospace charges near the semiconducting layers, which indicates that both electrons and holes were injected from the semiconducting layer.  相似文献   
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