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71.
High-aspect-ratio rutile and anatase hybrid nanowires are produced via a template-directed process using a novel cylindrical polyelectrolyte brush template. Loading the highly negatively charged 1D templates with pre-synthesized TiO(2) nanocrystals, results in the fabrication of soluble crystalline TiO(2) hybrid nanowires.  相似文献   
72.
Concentrations of 19 perfluorochemicals have been quantified in human blood and in some marine food resources from the region of the Gulf of Gda?sk at the Baltic Sea south coast in Poland. We indicate that in addition to PFOS and PFOA, a further 8 perfluorochemicals bioaccumulate in the human body. Food chain is an important route of exposure for all 10 perfluoroalkyl compounds detected in nonoccupationally exposed humans. Individuals who declared to have a high fish intake in their diet (mainly Baltic fish) on average contained the highest load of all 10 fluorochemicals when compared with the other human subpopulations. Baltic seafood has been found to highly influence human body burden of PFHxS, PFOS, PFOSA, PFHxA, PFHpA, PFNA, PFDA, PFUnDA, and PFDoDA, and to a lesser extent PFOA.  相似文献   
73.
Abstract— To investigate color breakup in field-sequential-color projectors, we measured the threshold of color fusion frequency relative to retinal velocity of the moving edge on the color flicker field. The characteristic changed as the velocity approached saccade. The result suggests that the mechanism of color breakup differs according to the velocity of the image on the retina.  相似文献   
74.
Relating to the microprocessor control and monitoring system applied in a GIS (gas insulated substation), this paper describes a series of reliability evaluation tests carried out during its development, and evaluation results on the basis of field data. According to the test results, it was found that the system developed has greater reliability for practical application from the viewpoint of EMC and life. In addition, a cost evaluation of the system developed was also carried out to compare the costs of a conventional system, thus verifying the economical advantages of the system developed  相似文献   
75.
Current-induced magnetization switching (CIMS) was demonstrated in low resistance magnetic tunnel junctions (MTJs) with thin MgO [001] barrier. The resistance change by CIMS was more than 100%, which is much larger than the previous report in Al-O based MTJs. The switching current density was about 2/spl times/10/sup 7/ A/cm/sup 2/, which was comparable with that reported values in metallic multilayers.  相似文献   
76.
A high-gain and high-efficiency slotted waveguide planar antenna is developed in the millimeter-wave band. Forty-five degree inclined polarization is required for automotive radar systems. In the design of slotted waveguide array for arbitrarily linear polarization, slot spacing is one guide wavelength which is larger than a wavelength in free space. Consequently, grating lobes appear in the radiation pattern. So, we developed a slotted waveguide planar antenna composed of post-loaded narrow-wall slots and a single-layer alternating-phase feeding circuit. A planar antenna with suppressed grating lobes has been fabricated and its RF performance has been measured. The measured gain is 33.2 dBi and antenna efficiency is 56% at 76 GHz. Grating lobe level is -28.6 dB lower than main lobe level. Since the proposed structure remains simple, the antenna is expected to be manufactured by metal injection molding for low cost  相似文献   
77.
This paper describes a method of detecting intruders by video image processing. There are some studies on detecting intruders in video image by analyzing difference-binary images and motion vectors. Because of the use of simple features such as size and motion vectors of changing regions, these methods are not fully able to reduce erroneous detection caused by other factors, such as small animals, swaying of trees, and changes in brightness. We propose a method of detecting intruders by time-series data on the projection pattern of the silhouette. In this method, changing regions in video images are extracted by the interframe differential technique and are transformed into projection patterns. Evaluation scores (a measure of similarity to a human silhouette) are calculated by flexible matching between observed patterns and the standard pattern. Discrimination processing is carried out in terms of a time-series score by tracking a target of each video frame. We have made experiments with a prototype and confirmed the effectiveness of this method. © 1997 Scripta Technica, Inc. Electr Eng Jpn 119(1): 62–73, 1997  相似文献   
78.
2,3-Bis(4-aminophenyl)quinoxaline (1a), 2,3-bis(4-aminophenyl)-6-methylquinoxaline (1b), and 5,6-bis(4-aminophenyl)-3-(2-pyridyl)-1,2,4-triazine (2) were studied as curing agents of epoxy resins. The exotherms on differential scanning calorimetry thermograms of the mixtures of diglycidyl ether of bisphenol A (DGEBA) with 1a, 1b, and 2 were observed at higher temperatures than that of the mixture of DGEBA with a commercially used diamine, for example, 4,4′-diaminodiphenylsulfone (DDS). However, the epoxy resin cured with 1a (EP-1a) showed higher tensile strength to stainless steel at 20°C than that cured with DDS, and the high tensile strength of EP-1a was maintained even at 180°C. The epoxy resin cured with 1b or 2 also possessed higher tensile strength at 20°C than that cured with DDS, but the high tensile strength lowered somewhat at 120°C. Using diamines 1a, 1b, and 2 as a curing agent improved heat distortion temperatures of the cured epoxy resins. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 69: 1737–1741, 1998  相似文献   
79.
Nucleophilic substitution reactions of 6-bromo-6-deoxycelluloses of high degrees of substitution with eight thiols having functional groups such as carboxyl and amino groups were studied under homogeneous conditions in LiBr-N, N-dimethylacetamide in the presence of triethylamine. The reactions under the homogeneous conditions proceeded more extensively than those run under heterogeneous conditions in aqueous alkaline solutions. The reactivity of thiols was found to increase with increasing acidity of the mercapto groups of the thiols. Reaction products with 2-mercaptobutanedioic acid and with 2-mercaptobenzoic acid were soluble in alkaline and neutral water but not in 1 N HCl, while the reaction products with 2-aminoethanethiol did not dissolve even in 1 N HCl. The reaction products with cysteine showed amphoteric behavior. © 1996 John Wiley & Sons, Inc.  相似文献   
80.
We investigated the relationship between respiratory syncytial virus (RSV) antigen and interferon (IFN) in nasopharyngeal secretions (NPS) and sera obtained from 252 patients infected with RSV. A total of 146 (57.9%) of 252 patients had IFN in NPS with a mean titer of 28 units/ml and IFN was detected in 164 (71.6%) of 229 patients in the acute stage sera with a mean titer of 28 units/ml. IFN activities were neutralized with antiserum to IFN-alpha. RSV antigen in NPS decreased on Day 5 and later in parallel with the change of mean titer of IFN in NPS. IFN in NPS was detected in 40 to 60% of the samples with some fluctuation in the acute stage. Within 4 days IFN was detected in more than 70% of the sera whereas on Day 5 and later the IFN positivity rate decreased in sera. RSV antigen in NPS decreased in the older patient groups. No significant change of positive rate of IFN in NPS was observed in different age groups and the mean titer of IFN in NPS and sera did not vary with age, except in those younger than 3 months and older than 3 years of age.  相似文献   
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