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排序方式: 共有550条查询结果,搜索用时 15 毫秒
41.
T Fujimatsu M Tsunemoto M Shimada Y Ohta S Endo A Ishizawa K Koike M Akagi T Watari J Kobayashi 《Canadian Metallurgical Quarterly》1990,10(1):76-80
This report concerns a 10-month-old infant with subtotal cor triatrium associated with left sided partial anomalous pulmonary venous connection to the innominate vein. In the operation, we found that the fossa ovalis existed between the right atrium and the accessory atrial chamber. We performed a radical operation which consisted of a resection of the intra-left-atrial diaphragma and a anastomosis of the vertical vein to the left atrium. His postoperative course was uneventful, and the result was satisfactory. We have presented and reviewed our case, and then discussed the embryogenesis and the hemodynamics. To our knowledge, our case represents the first successful surgical repair of this combination of defects in Japan. 相似文献
42.
Masatomo Yashima Nobuo Ishizawa Masahiro Yoshimura 《Journal of the American Ceramic Society》1992,75(6):1541-1549
Oxygen vacancies can be introduced into zirconia solid solution ZrO2 –MO u ( u = 1 and 1.5) to maintain electroneutrality. Recently, the local structures around Zr4+ and M2 u + ions in ZrO2 –MO u solid solutions have been studied through EXAFS spectroscopy, diffuse scattering analysis, and single-crystal structure analysis. The present study constructs an ion-packing model for zirconia solid solutions based on some defect cluster models. The decrease of cell volume with the occurrence of vacancies is assumed to be expressed by decreasing the coordination number (CN) of cations around the vacancy. The distribution of CNs in a solid solution was calculated from a certain defect cluster model. The average interatomic distances, the average CN, and the short-range order parameters were calculated using this distribution of CNs. The local structures calculated from the model were compared with experimental data in the systems ZrO2 –MO1.5 (M = Y, Gd, Yb, and Ca). In the ZrO2 –YO1.5 system, the r (s–O) interatomic distance, where s represents Zr4+ or Y3+ and O represents O2− , decreased with Y content and therefore vacancy content. The probability of finding Y3+ around a vacancy increases with increasing yttria content from a comparison of the calculated results with the ones from recent EXAFS studies. The present model can qualitatively explain compositional and size dependences of the dopant on various local structures. 相似文献
43.
Shin’ichi Konno Shigeo Kazama Maki Hiraoka Hirokazu Sakamoto Kenji Mizoguchi Hiromi Taniguchi Toshikazu Nakamura Kou Furukawa 《Journal of Low Temperature Physics》2006,142(3-4):621-624
β′-(BEDT-TTF)(TCNQ) is a compound of BEDT-TTF (=ET) and TCNQ molecules aligned orthogonally with each other, forming two-dimensional
sheets and one-dimensional columns of 1/4-filled π band, respectively. It is known that the metal-insulator transition occurs
at 330 K at ambient pressure. We have measured the electronic spin susceptibility by means of the EPR-NMR method at 50 MHz,
and the angular dependence of g-factor and line width of EPR both at Q (34 GHz) and W (94 GHz) band. We successfully confirmed
that the antiferromagnetic transition occurs in ET sheets and TCNQ columns, independently. 相似文献
44.
Yusuke Suzuki Chisato Takenaka Rie Tomioka Hiromi Tsubota Yuka Takasaki Tomonari Umemura 《Mine Water and the Environment》2016,35(3):265-272
Bryophytes with high As accumulation affinity were identified in the aquatic environment. We surveyed a stream near copper mine tailings and then conducted laboratory experiments to confirm As accumulation in the bryophytes with high As affinity. We found that a moss, Scopelophila cataractae, accumulates As in addition to Cu in aquatic environments and confirmed it in laboratory experiments. The highest value for As in S. cataractae from the field survey was 1300 mg/kg dry weight at relatively low As concentrations in the stream water (0.005 mg/L). In addition, Brachythecium plumosum and Rhynchostegium riparioides may also be useful bryophytes for accumulation of Cu and As, though the mechanisms of As accumulation might differ between these two bryophytes and S. cataractae. 相似文献
45.
Hiromi Nakano Motohiro Yamada Masahiro Fukumoto Eiji Yamaguchi 《Journal of Thermal Spray Technology》2011,20(3):407-411
Cold spraying has been developed as a high-quality coating technique. In this article, copper is deposited on an AlN substrate
coated by the sputtering of titanium and copper at a low pressure of less than 1.0 MPa, making this approach suitable for
a wide range of engineering applications. In order to understand the adhesion mechanism at the atomic scale, the interfacial
regions are carefully observed in thin foil samples from the cross sections of the specimens with a HREM. We find a unique
wavy boundary between the sputtered titanium and the sputtered copper. It is assumed that the shear-instability phenomenon
occurs due to the cold-spraying process and influences the adhesive strength. Furthermore, the cold-sprayed copper particles
are connected directly without any oxidation layer due to the appearance of new metallic surfaces during the impact process.
The TEM data clearly reveal the phenomena and mechanisms related to the impact of powder sprayed on the substrate. 相似文献
46.
Ozasa K Shimizu Y Sakata R Sugiyama H Grant EJ Soda M Kasagi F Suyama A 《Radiation protection dosimetry》2011,146(1-3):272-275
Late health effects of exposure to atomic bomb radiation have been evaluated in survivors. A cohort of 120 321 people has been followed since 1950 for mortality, including the cause of death using the Japanese population registry system (Life Span Study), and for cancer incidence using population-based cancer registries. Findings have included a markedly increased risk of leukaemia several years after the exposure, increased risk of various malignant tumours several decades after the exposure and, more recently, findings of increased rates of non-cancer diseases such as cardiovascular diseases. 相似文献
47.
Four-terminal electrical measurement is realized on a microscopic structure in air, without a lithographic process, using a home-built quadruple-scanning-probe force microscope (QSPFM). The QSPFM has four probes whose positions are individually controlled by obtaining images of a sample in the manner of atomic force microscopy (AFM), and uses the probes as contacting electrodes for electrical measurements. A specially arranged tuning fork probe (TFP) is used as a self-detection force sensor to operate each probe in a frequency modulation AFM mode, resulting in simultaneous imaging of the same microscopic feature on an insulator using the four TFPs. Four-terminal electrical measurement is then demonstrated in air by placing each probe electrode in contact with a graphene flake exfoliated on a silicon dioxide film, and the sheet resistance of the flake is measured by the van der Pauw method. The present work shows that the QSPFM has the potential to measure the intrinsic electrical properties of a wide range of microscopic materials in situ without electrode fabrication. 相似文献
48.
Ghosts and flares are well-known problems that are caused by reflections from lens surfaces when we take photographs. It is more difficult to prevent such stray light in a digital camera than in a film camera because of high reflectance from the low-pass filter and diffraction from the image sensor. To prevent such stray light, we introduce an ultralow refractive index layer into the antireflective (AR) coatings. We used the solgel method to form porous fluoride layers with ultralow refractive indices, and we succeeded in developing a unique process to form AR coatings with superior performance. 相似文献
49.
乳糖酸(Lactobionicacid)是乳糖氧化的产物,具有多种生理功能。目前,欧美等发达国家乳糖酸的生产是通过化学合成法,生产成本高,且有大量副产物生成。研究采用具有葡萄糖氧化酶的菌株BurkholderiacepaciaNo.24细胞培养物进行生物转化生产乳糖酸,55g湿重/1000mL细胞可将浓度为193mmol/L的乳糖转化成188mmol/L的乳糖酸,转化率可达99.8%,且转化液经薄层色谱层析和高效液相色谱检测证明在转化过程中没有副产物生成;同时,该菌株还具有广泛的底物专一性,能将葡萄糖、麦芽糖等糖类转化成相应的糖酸。 相似文献
50.
The activity of beta-cyanoalanine synthase (CAS, EC 4.4.1.9) in cotyledons of cocklebur seeds (Xanthium pennsylvanicum Wallr.) was detected both in the soluble and particulate fractions. The CAS activity of the soluble fraction (cytosolic CAS activity) was 10 times higher than that of the particulate fraction. The CAS activity of the particulate fraction was confirmed to be localized in the mitochondria. Both enzymatic activities were clearly separated by non-denaturing PAGE. The enzyme with cytosolic CAS activity has been extensively purified and separated into three different forms designated as cyt-1, cyt-2, and cyt-3. According to the SDS-PAGE analysis, the three enzymes are estimated to be a homodimer composed of 35-kDa subunits. The purified enzymes showed CS activity. Partial amino acid sequences of cyt-1 were determined and had a high homology with cysteine synthases (CS, EC 4.2.99.8) from other plant sources. The catalytic action of the purified CSs in converting cyanide and cysteine into H2S and beta-cyanoalanine was confirmed by the detection of significant 14CN incorporation into beta-cyanoalanine. These results indicated that cytosolic CAS activity is due to cytosolic CS and suggested that the CAS activity of CS is likely to be involved in cyanide metabolism in plant tissues. 相似文献