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排序方式: 共有1163条查询结果,搜索用时 15 毫秒
61.
Dr. Naoki Umezawa Yuhei Horai Dr. Yuki Imamura Makoto Kawakubo Mariko Nakahira Dr. Nobuki Kato Akira Muramatsu Prof. Dr. Yuko Yoshikawa Prof. Dr. Kenichi Yoshikawa Prof. Dr. Tsunehiko Higuchi 《Chembiochem : a European journal of chemical biology》2015,16(12):1811-1819
A versatile solid‐phase approach based on peptide chemistry was used to construct four classes of structurally diverse polyamines with modified backbones: linear, partially constrained, branched, and cyclic. Their effects on DNA duplex stability and structure were examined. The polyamines showed distinct activities, thus highlighting the importance of polyamine backbone structure. Interestingly, the rank order of polyamine ability for DNA compaction was different to that for their effects on circular dichroism and melting temperature, thus indicating that these polyamines have distinct effects on secondary and higher‐order structures of DNA. 相似文献
62.
Change in liquid temperature behind the impeller blades with impeller speed in boiling stirred tanks
In our previous study (Fukuda, R., Tokumura, M., Znad, H.T. and Kawase, Y., 2009, Vapour generation from the impellers in boiling stirred tank reactors. Chem Eng Res Des, 87: 452–459), it was found that in boiling stirred tanks with multiple impeller systems vapour was generated from the heater at lower impeller speeds and with an increase in impeller speed most vapour was generated from the top impeller rather than the lower impellers and the heater. The change of nucleation sites with the impeller speed might be controlled by the local liquid temperature. Therefore we measured the liquid temperature behind the impellers blades and found the decrease in liquid temperature with increasing impeller speed. In this paper, a simple model was developed to predict the change in liquid temperature behind the impeller blades in which nucleation takes place. In the proposed model based on the results for pressure distribution on the impeller blade in the literature, the liquid temperature behind the impeller blades is estimated from the measured power consumption. The validation of the proposed model was conducted using the experimental results in our previous study and reasonable agreement was obtained. 相似文献
63.
V. Matolín M. Cabala I. Matolínov M. koda M. Vclav K.C. Prince T. Skla T. Mori H. Yoshikawa Y. Yamashita S. Ueda K. Kobayashi 《Fuel Cells》2010,10(1):139-144
The interaction of Pt with CeO2 layers was investigated by using photoelectron spectroscopy. Thirty‐nanometre‐thick Pt and Sn doped CeO2 layers were deposited simultaneously by rf‐magnetron sputtering on a Si(001) substrate and a carbon diffusion layer of a polymer membrane fuel cell by using a composite CeO2–Pt–Sn target. The laboratory XPS and synchrotron radiation soft X‐ray and hard X‐ray photoemission spectra showed the formation of cerium oxide with completely ionised Pt2+,4+ species, and with Pt4+ embedded in the film bulk. Hydrogen/air fuel cell activity measurements normalised to the amount of Pt used revealed high specific power of up to 5.4 × 104 mW mg–1 (Pt). The activity of these materials is explained by the strong activity of embedded Ptn+ cations. 相似文献
64.
Arima J Uesugi Y Iwabuchi M Hatanaka T 《Protein engineering, design & selection : PEDS》2008,21(1):45-53
We purified and characterized the aminopeptidase P from Streptomyces costaricanus TH-4 (thAPP). This enzyme has a tetramer structure, a metal-ion preference toward Zn, broad substrate specificity and a narrow pH dependency for activity. The primary structure of thAPP, respectively, exhibits 91% and 65% identity with those of two other APPs-APP I and APP II-from Streptomyces lividans (slAPP I and slAPP II). We next overexpressed the genes encoding thAPP and slAPP II in Escherichia coli and characterized them. Two differences were apparent in their properties: slAPP II formed a dimer, whereas thAPP formed a tetramer; also, the alkaline side pKa for the catalytic action of slAPP II is higher than that of thAPP. Investigation using chimeras of both enzymes revealed that the N-terminal domain is associated with the determination of pKa values for catalytic action and quaternary structure. 相似文献
65.
Mikio Enoeda Hisashi Tanigawa Takanori Hirose Satoshi Suzuki Kentaro Ochiai Chikara Konno Yoshinori Kawamura Toshihiko Yamanishi Tsuyoshi Hoshino Masaru Nakamichi Hiroyasu Tanigawa Koichiro Ezato Yohji Seki Akira Yoshikawa Daigo Tsuru Masato Akiba 《Fusion Engineering and Design》2012,87(7-8):1363-1369
The development of a Water Cooled Ceramic Breeder (WCCB) Test Blanket Module (TBM) is being performed as one of the most important steps toward DEMO blanket in Japan. For the TBM testing and evaluation toward DEMO blanket, the module fabrication technology development by a candidate structural material, reduced activation martensitic/ferritic steel, F82H, is one of the most critical items from the viewpoint of realization of TBM testing in ITER. In Japan, fabrication of a real scale first wall, side walls, a breeder pebble bed box and assembling of the first wall and side walls have succeeded. Recently, the real scale partial mockup of the back wall was fabricated. The fabrication procedure of the back wall, whose thickness is up to 90 mm, was confirmed toward the fabrication of the real scale back wall by F82H. Important key technologies are almost clarified for the fabrication of the real scale TBM module mockup. From the view point of testing and evaluation, development of the technology of the blanket tritium recovery, development of advanced breeder and multiplier pebbles and the development of the blanket neutronics measurement technology are also performed. Also, tritium production and recovery test using D-T neutron in the Fusion Neutronics Source (FNS) facility has been started as the verification test of tritium production performance. This paper overviews the recent achievements of the development of the WCCB TBM in Japan. 相似文献
66.
Makoto Sugiyama Yutaka FujimotoTakayuki Yanagida Yuui YokotaJan Pejchal Yuki FuruyaHidehiko Tanaka Akira Yoshikawa 《Optical Materials》2011,33(6):905-908
Nd 0.1%, 0.5%, 1% and 3% doped Lu3Al5O12 (Nd:LuAG) single crystals were grown in the nitrogen atmosphere by the micro-pulling down (μ-PD) method. The grown crystals had a single-phase confirmed by powder XRD analysis. In absorption spectra, some weak absorption lines due to Nd3+ 4f-4f transitions were observed and their intensity increased with the increase of Nd concentration. When excited by 241Am α-ray, a broad emission peak due to defects in the host lattice at 320 nm and some sharp lines due to Nd3+ 4f-4f transitions at wavelength longer than 400 nm were observed. The decay time profiles of Nd:LuAG under γ-ray excitation were well approximated by two exponential function of 340-760 ns and 3-5 μs for each sample. By pulse height measurement using 137Cs, Nd 0.5%:LuAG showed the highest light yield of 7600 ± 760 photons/MeV. 相似文献
67.
Theoretical design of pseudo-ternary and quaternary alloys by superlattice structures consisting of (Zn,Cd)(S,Se) binary II–VI
compounds has been studied. For pseudo-ternary ZnCdS and ZnCdSe alloys, the superlattices with two layers in a cycle, i.e.,
ZnS/CdS and ZnSe/CdSe are considered, and for pseudo-quaternary ZnCdSSe alloy, the two superlattice structures with more than
two layers in a cycle are considered. In order to design and evaluate these superlattices, the expression for the equilibrium
in-plane lattice constant of these superlattices has been derived by minimizing the total elastic strain energy in the cycle.
The combinations of layer thicknesses in a cycle and the effective bandgap of these superlattices have been calculated while
the elastic strain effect was included. The usefulness of these superlattice structures has been evaluated. 相似文献
68.
A network-theoretic approach to the design of a dynamic precompensator C (s ) for a multiinput, multioutput plant T (s ) is considered. The design is based on the relative degree of each element of T (s ). Specifically, an efficient algorithm is presented for determining whether a given plant T (s ) has a diagonal precompensator C ( s ) such that, for almost all cases, T (s )C (s ) has a diagonal interactor. The algorithm also finds any optimal precompensator, in the sense that the total relative degree is minimal. The algorithm can be easily modified to work even when a T (s ) represented by a nonsquare matrix is given 相似文献
69.
Scintillation properties of Tm-doped Lu3Al5O12 single crystals 总被引:1,自引:0,他引:1
Makoto Sugiyama Yutaka Fujimoto Takayuki Yanagida Daisuke Totsuka Yuui Yokota Akira Yoshikawa 《Optical Materials》2011,34(2):439-443
Using the micro-pulling-down (μ-PD) method, Tm-doped Lu3Al5O12 (Tm:LuAG) single crystals were grown to examine their scintillation properties. In transmittance spectra, they exhibited about 80% transparency in the wavelengths longer than 320 nm and five absorption lines due to Tm3+ 4f–4f transitions were observed. 241Am α-ray excited radioluminescence spectra were measured and intense 4f–4f emission peaks were observed with the host emission. When excited by 137Cs γ-Ray to obtain pulse height spectra, Tm 1% doped LuAG showed the highest light yield coupled with a photomultiplier (PMT) or a silicon avalanche photodiode (Si-APD). The light yield was estimated to be 5800 and 7300 photons/MeV for PMT and Si-APD, respectively. Decay time profiles consist of two exponential components and the fast and slow components are considered to be attributed to the host and the combination of the host and Tm3+ 4f–4f emission, respectively. 相似文献
70.
Nomura SM Tsumoto K Hamada T Akiyoshi K Nakatani Y Yoshikawa K 《Chembiochem : a European journal of chemical biology》2003,4(11):1172-1175
Functional protein synthesis was observed in cell-sized lipid vesicles following encapsulation of a gene-expression system. Expression of rsGFP (red-shifted green fluorescent protein) within individual vesicles was observed by fluorescence microscopy. Interestingly, at the early stage of the reaction, the expression efficiency inside the vesicle was remarkably higher than that in the solution outside. The synthesized rsGFP in individual vesicles is safe from attack by proteinase K added to the external aqueous solution. Studies on cell-sized vesicles expressing protein should contribute to a fundamental understanding of certain aspects of living systems and will be useful for practical applications, such as the construction of microreactors. 相似文献