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31.
The method has been developed to improve the bitumen product which incorporates an evaporator concentrate from a BWR, with respect to the swelling and leaching. The leachability of the product has been measured by the method recommended by the IAEA. The swelling of the product is successfully prevented by the addition of calcium chloride. The specimen containing the waste up to Wa/B (Weight ratio of Na2SO4 + CaCl2 and bitumen) = 60:40 shows no pronounced swelling, when it is immersed in water. The cumulative fractions of 137Cs and 60Co leached from a specimen which does not contain CaCl2 are 0.65 and 0.2 at the leaching time of 30 days. On the hand, the corresponding value at 100 days for the specimen with calcium chloride addition is 5 × 10?4 for 137Cs and 1 × 10?4 for 60Co. The coating of the specimen surface with a fresh bitumen (5 mm thickness) reduces the leachability further. These results indicate that this method is effective to improve the bitumen product incorporating BWR's evaporator concentrate. 相似文献
32.
Sasao T Itoh N Takano H Watanabe S Wei G Tsukamoto T Kuzumaki N Takimoto M 《Reproduction (Cambridge, England)》2004,128(6):709-716
We have previously identified and cloned a human gene, D40, that is preferentially expressed in testis among normal organs, while it is widely expressed in various human tumor cell lines and primary tumors derived from different organs. In this report, we have examined the expression and localization of this protein in human testis with an antibody specific to D40 protein. In Western analyses, the anti-D40 antibody recognized a major band with a molecular mass of 300 kDa and a minor band of 250 kDa. These bands were not observed in the testis lysates from patients with Sertoli-cell-only syndrome and with Kleinfelter syndrome, who lack germ cells of the testis, indicating that D40 protein is expressed in the germ cells of normal testis. Immunohistochemical studies have revealed that D40 protein is highly expressed in spermatocytes and in the pre-acrosome of round spermatids. In the acrosome, D40 protein expression is observed not inside but outside the acrosome membrane. This is consistent with the finding that the amino-acid sequence at the amino terminal of the D40 protein lacks a hydrophobic signal peptide that is required for proteins to translocate to the membrane. Expression of D40 protein is observed in the acrosome of ejaculated spermatozoa as well, although the level is low compared with that in the pre-acrosome of spermatids. These results suggest that D40 protein plays important roles in spermatogenesis, especially in the formation and maintenance of the acrosome. 相似文献
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Tajima T Takiguchi N Kato J Ikeda T Kuroda A Ohtake H 《Journal of Bioscience and Bioengineering》2003,96(2):149-153
The nematode Caenorhabditis elegans exhibits chemotaxis toward a wide variety of chemicals including water-soluble molecules and volatile organic compounds. We have previously discovered that C. elegans wild-type strain N2 is strongly attracted by cycloheximide which has long been known as a bitter tastant for humans and other mammals. We describe here the isolation and initial characterization of the first mutants which were defective specifically in their attraction to cycloheximide. In our screenings, we selected two mutants that were defective in chemotaxis to cycloheximide but normal in their attraction to NH4Cl and histidine. These mutants also avoided quinine hydrochloride, CuSO4 and high concentrations of NaCl similar to the wild-type strain N2. Furthermore, no observable defect was detected in their attraction to volatile odorants such as isoamyl alcohol and diacetyl. Dye-filling experiments suggested that they have no morphological defect in the sensory endings of the amphid neurons. 相似文献
36.
Hiroyuki Moriuchi Yoshihiro Tadokoro Masahide Sato Takeshi Furusawa Noboru Suzuki 《Journal of Electronic Materials》2007,36(3):220-225
Lead-free commercial products have been dramatically increasing in the world markets as the restriction of certain hazardous
substances (RoHS) directive in the European Union has been enacted. At the same time, the problem of “tin whiskers” has become
one of the most serious problems in the industry. Growth of tin whiskers is believed to be related to residual stress inside
the tin plating film and external compressive stress. Whiskers in fine-pitch connectors have affected the practical production
of advanced digital equipment. The Japan Electronics and Information Technology Industries Association (JEITA) has proposed
a new testing method to evaluate tin whiskers, especially for the fine-pitch connectors. This paper describes the microstructures
of external stress whiskers and the mechanical indentation test method. 相似文献
37.
Shuang Bai Tetsuya Matsumoto Yoshinori Takeuchi Hiroaki Kudo Noboru Ohnishi 《Machine Vision and Applications》2013,24(5):959-970
In image classification based on bag of visual words framework, image patches used for creating image representations affect the classification performance significantly. However, currently, patches are sampled mainly based on processing low-level image information or just extracted regularly or randomly. These methods are not effective, because patches extracted through these approaches are not necessarily discriminative for image categorization. In this paper, we propose to utilize both bottom-up information through processing low-level image information and top-down information through exploring statistical properties of training image grids to extract image patches. In the proposed work, an input image is divided into regular grids, each of which is evaluated based on its bottom-up information and/or top-down information. Subsequently, every grid is assigned a saliency value based on its evaluation result, so that a saliency map can be created for the image. Finally, patch sampling from the input image is performed on the basis of the obtained saliency map. Furthermore, we propose a method to fuse these two kinds of information. The proposed methods are evaluated on both object categories and scene categories. Experiment results demonstrate their effectiveness. 相似文献
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This paper describes the cogging torque characteristics of a magnetic‐geared motor with permanent magnets only on the high‐speed rotor. The operational principle, which is different from that of the magnetic‐geared motor with permanent magnets on the high‐speed rotor and stator, is described. The torque characteristics, especially the order of the cogging torque, are mathematically formulated and verified by conducting 3D finite element analysis and carrying out measurements on a prototype. A novel cogging torque reduction method is proposed and verified as well. 相似文献
40.
A hydrogen internal combustion engine (HICE) wastes more heat, and producing nearly three times more water than a conventional engine. This paper describes the principle behind a novel waste heat recovery sub-system that exploits the water produced by an HICE as the working fluid for an open-cycle power generation system based on the Rankine cycle. Water from the HICE exhaust is superheated by the waste heat from the HICE and used to produce power in a steam expander. A fundamental thermodynamic model shows the contribution of the sub-system to the overall thermal efficiency of the HICE at various engine speeds, with and without a condenser. The results show that the condenser is not cost-effective and that the overall thermal efficiency with the proposed sub-system is 27.2% to 33.6%, representing improvements of 2.9% to 3.7%, at engine speeds of 1500 to 4500 rpm. 相似文献