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排序方式: 共有1061条查询结果,搜索用时 15 毫秒
81.
Tsuyoshi Tagata Mayumi Nishida Atsushi Nishida 《Advanced Synthesis \u0026amp; Catalysis》2010,352(10):1662-1666
A new continuous‐flow system for C H borylation has been developed. An insoluble catalyst prepared from chloro(1,5‐cyclooctadien)iridium(I) dimer and 2,2′‐bipyridine‐4,4′‐dicarboxylic acid in the presence of bis(pinacolato)diboron exhibited high reactivity under continuous‐flow processing without the loss of expensive iridium metal. 相似文献
82.
The tissue structures of 2-year-old konjac tubers were investigated using a variable pressure scanning electron microscope equipped with an energy-dispersive X-ray spectrometer and an optical microscope. Konjac mannan (KM) cells are distributed all over the tuber and the spaces between the KM cells are filled with parenchyma. The KM cells are covered with scale-like cell walls and the size of the cells varies from 160 to 650 μm. Other kinds of particles with different sizes are observed in the honeycombed cells around the KM cells. The small grains relate to protein granules and the spherical particles (~12 μm in diameter), which are composed of small granules (1–3 μm in diameter), are starch. The tuber also contains potassium and calcium in the parenchyma. Most calcium is found in the needle-like crystals in the form of calcium oxalate. Such crystals are also found in 1 year and seed tubers. 相似文献
83.
Identification of yeast strains isolated from marcha in Sikkim, a microbial starter for amylolytic fermentation 总被引:1,自引:0,他引:1
Tsuyoshi N Fudou R Yamanaka S Kozaki M Tamang N Thapa S Tamang JP 《International journal of food microbiology》2005,99(2):135-146
Marcha or murcha is a traditional amylolytic starter used to produce sweet-sour alcoholic drinks, commonly called jaanr in the Himalayan regions of India, Nepal, Bhutan, and Tibet (China). The aim of this study was to examine the microflora of marcha collected from Sikkim in India, focusing on yeast flora and their roles. Twenty yeast strains were isolated from six samples of marcha and identified by genetic and phenotypic methods. They were first classified into four groups (Group I, II, III, and IV) based on physiological features using an API test. Phylogenetic, morphological, and physiological characterization identified the isolates as Saccharomyces bayanus (Group I); Candida glabrata (Group II); Pichia anomala (Group III); and Saccharomycopsis fibuligera, Saccharomycopsis capsularis, and Pichia burtonii (Group IV). Among them, the Group I, II, and III strains produced ethanol. The isolates of Group IV had high amylolytic activity. Because all marcha samples tested contained both starch degraders and ethanol producers, it was hypothesized that all four groups of yeast (Group I, II, III, and IV) contribute to starch-based alcohol fermentation. 相似文献
84.
Fujita K Miyamura T Sano M Kato I Takegawa K 《Journal of Bioscience and Bioengineering》2002,93(6):614-617
Endo-beta-N-acetylglucosaminidase from Arthrobacter protophormiae (Endo-A) has transglycosylation activity, and high-mannose-type oligosaccharides are transferred to suitable glycosides as acceptor substrates. The acceptor specificity of Endo-A-catalyzed transglycosylation toward various disaccharides was investigated. To identify an effective acceptor for the transglycosylation by Endo-A, the reaction was carried out using various disaccharides. Endo-A transferred high-mannose-type oligosaccharides more efficiently to beta-linked disaccharides (cellobiose, gentiobiose, sophorose, and laminaribiose) than to alpha-linked disaccharides (isomaltose, maltose, nigerose, kojibiose, and trehalose) as acceptor substrates. The transglycosylation products, (Man)6GlcNAc-Glc-beta-Glc, were more rapidly hydrolyzed than (Man)6GlcNAc-Glc-alpha-Glc. These results indicate that Endo-A recognizes the anomeric configuration of the acceptor substrates, and beta-linked glycosides are suitable for the synthesis of transglycosylation products. 相似文献
85.
When the underexpanded supersonic jet impinges on the obstacle, it is well known that the self-induced flow oscillation occurs at the specific condition of the pressure ratio in the flowfield, the position of an obstacle and so on. This oscillation is related with the noise problems of aeronautical and other industrial engineering so that the characteristic and the mechanism of self-induced flow oscillation have to be cleared to control the various noise problems. But, it seems that the characteristics of t... 相似文献
86.
Koutaki Gou Ando Sakino Shirai Keiichiro Kishigami Tsuyoshi 《International Journal of Computer Vision》2022,130(9):2286-2304
International Journal of Computer Vision - In April 2016, a massive earthquake with a magnitude of 7.3 struck Kumamoto region, Japan, causing major devastation. One of the structures that were... 相似文献
87.
Akihisa Inoue Nobuyoshi Yano Kunio Matsuzaki Tsuyoshi Masumoto 《Journal of Materials Science》1987,22(5):1827-1834
Copper-based superconducting alloys including finely dispersed f c c lead or h c p (Pb- Bi) particles in f c c copper matrix have been obtained by rapid quenching (Cu-M)100-x
Pbx and (Cu-M)100-x
(Pb0.6Bi0.4
x
(M = aluminium, silicon or tin;x < 10 at%) alloys containing immiscible elements such as lead and bismuth. The particle size and interparticle distance were about 30 to 130 nm and 20 to 200 nm for had particles and about 30 to 60 nm and 30 to 150 nm for (Pb- Bi) particles. The transition temperature,T
c, was in the range of 3.2 to 5.5 K for the Cu-M-Pb alloys and 6.2 to 6.3 K for the Cu-M-Pb-Bi alloys. Critical magnetic field,H
c2, and critical current density,J
c, for the later alloys were 0.47 to 0.93T at 4.2 K and 1.1 × 105 to 2.7 × 105 Am–2 at zero applied field and 4.21 K. The mechanism of the appearance of such a soft-type superconductivity for the rapidly quenched copper-based alloys was discussed, and inferred to be due to the formation of a percolation path of a superconducting lead or Pb-Bi phase along the grain boundaries, sub-boundaries and/or tangled dislocations where the lead or Pb-Bi phase precipitated preferentially, rather than the proximity effect based on lead or Pb-Bi particles. 相似文献
88.
89.
Flexible electronic circuits are an essential prerequisite for the development of rollable displays, conformable sensors, biodegradable electronics and other applications with unconventional form factors. The smallest radius into which a circuit can be bent is typically several millimetres, limited by strain-induced damage to the active circuit elements. Bending-induced damage can be avoided by placing the circuit elements on rigid islands connected by stretchable wires, but the presence of rigid areas within the substrate plane limits the bending radius. Here we demonstrate organic transistors and complementary circuits that continue to operate without degradation while being folded into a radius of 100 μm. This enormous flexibility and bending stability is enabled by a very thin plastic substrate (12.5 μm), an atomically smooth planarization coating and a hybrid encapsulation stack that places the transistors in the neutral strain position. We demonstrate a potential application as a catheter with a sheet of transistors and sensors wrapped around it that enables the spatially resolved measurement of physical or chemical properties inside long, narrow tubes. 相似文献
90.
Kunihiro Ogata Tokio Umino Tsuyoshi Nakayama Eiichi Ono Toshiaki Tsuji 《Advanced Robotics》2017,31(6):303-310
Development of clothing in consideration of the shape and body function of a person with spinal cord injury is an important task. Then, a dummy robot with a deformation mechanism was developed in this study for evaluating the comfortable level of clothings. Specifically, a trunk joint mechanism and an abdominal mechanism that can realize various deformations of the abdominal area and various trunk poses were developed. The trunk joint mechanism was implemented in order to simulate the seated posture of persons with spinal cord injury. The abdominal deformation mechanism was implemented using linear actuators and rotating servomotors in order to simulate abdominal obesity of persons with spinal cord injury. Further, a tactile sensor system was developed for measuring the clothing pressure on the abdominal area and evaluating the comfort or discomfort of clothing. 相似文献