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81.
MA Yue S.Ajimura K.Aoki M.Dairaku Fu Yuan-yong H.Fujioka T.Fukuda K.Futatsugawa K.Hosomi W.Imoto M.Kawai Y.Kakiguchi S.Kinoshita T.Koike N.Maruyama M.Mimori S.Minami Y.Miura K.Miwa Y.Miyagi T.Nagae D.Nakajima H.Noumi K.S hirotori T.Suzuki T.Takahashi T.N.Takahashi K.Tanida N.Terada A.Toyoda K.Tsukada M.Ukai ZHOU Shu-hua H.Tamura 《原子核物理评论》2009,26(Z1)
In this proceeding,we will first outline the experimental setup and main results of the most recent hypernuclear γ-ray spectroscopy experiment (KEK-E566) performed at KEK-PS K6 beam line.The main feature and characteristics of this type of research will he emphasised.After that,the approved experimental proposal (E13) at J-PARC facility will be introduced briefly. 相似文献
82.
Takashi Miyagi 《Tetrahedron letters》2004,45(33):6303-6305
Lithium trimethylsilyldiazomethane smoothly reacted with N-tosyl-o-acylanilines to give 3-substituted indoles in good to high yields. 相似文献
83.
S. M. Abdur Razzak Yoshinori Namihira Feroza Begum Kazuya Miyagi Shubi Kaijage Nguyen Hoang Hai Tatsuya Kinjo Nianyu Zou 《Optical Review》2007,14(4):165-168
This paper presents dispersion-flattened modified hexagonal photonic crystal fibers (MH-PCFs) with extremely low confinement
loss. The finite difference method (FDM) with an anisotropic perfectly matched boundary layer (PML) is used to investigate
the chromatic dispersion and confinement properties. It is demonstrated that it is possible to obtain an ultra-flattened dispersion
of 0 ± 0:41 ps/(nm·km) in the wavelength range of 1.35–1.65 mm and an extremely low confinement loss of less than 10−4 dB/km from a four-ring MH-PCF. Effective single-mode operation of the MH-PCF is confirmed for the entire band of interest. 相似文献
84.
Synthesis and Helical Structures of Poly(ω‐alkynamide)s Having Chiral Side Chains: Effect of Solvent on Their Screw‐Sense Inversion
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Yuji Suzuki Yu Miyagi Prof. Dr. Masashi Shiotsuki Prof. Dr. Yoshihito Inai Prof. Dr. Toshio Masuda Prof. Dr. Fumio Sanda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(46):15131-15143
New ω‐alkynamides, (S)‐HC?CCH2CONHCH2CH(CH3)CH2CH3 ( 1 ) and (S)‐HC?CCH2CH2CONHCH(CH3)CH2CH2CH2CH2CH3 ( 2 ) were synthesized and polymerized with a rhodium catalyst in CHCl3 to obtain cis‐stereoregular poly(ω‐alkynamide)s (poly( 1 ) and poly( 2 )). Polarimetric, CD, and IR spectroscopic studies revealed that in solution the polymers adopted predominantly one‐handed helical structures stabilized by intramolecular hydrogen bonds between the pendent amide groups. This behavior was similar to that of the corresponding poly(N‐alkynylamide) counterparts (poly( 3 ) and poly( 4 )) reported previously, whereas the helical senses were opposite to each other. The helical structures of the poly(ω‐alkynamide)s were stable upon heating similar to those of the poly(N‐alkynylamide)s, but the solvent response was completely different. An increase in MeOH content in CHCl3/MeOH resulted in inversion of the predominant screw‐sense for poly( 1 ) and poly( 2 ). Conversely, poly( 3 ) was transformed into a random coil, and poly( 4 ) maintained the predominant screw‐sense irrespective of MeOH content. The solvent dependence of predominant screw‐sense for poly( 1 ) and poly( 2 ) was reasonably explained by molecular orbital studies using the conductor‐like screening model (COSMO). 相似文献
85.
86.
Steroid family has various bioactivities and characteristic polycyclic structure. Although several synthetic methods have been reported, more efficient way is desired for medicinal chemistry. In this Letter, we synthesized pseudoenantiomers of tricyclic enones toward both enantiomers for ABC-ring moiety of steroids utilizing d-mannitol as a chiral source. The key steps are radical domino cyclization of polyalkenyl-β-keto ester into tricyclic keto ester and subsequent dealkoxycarbonylation. 相似文献
87.
Fritz Sieber Jean-Pierre Daziano Wolfgang H. H. Günther Marianne Krieg Kiyoko Miyagi Reynée W. Sampson 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):647-657
Abstract Elemental selenium generated by the photobleaching of selenomerocyanine dyes forms conjugates with serum albumin and serum lipoproteins that are toxic to leukemia and selected solid tumor cells but well tolerated by normal CD34-positive hematopoietic stem and progenitor cells. Serum albumin and lipoproteins act as Trojan horses that deliver the cytotoxic entity (elemental selenium) to tumor cells as part of a physiological process. They exploit the fact that many tumors have an increased demand for albumin and/or low-density lipoprotein. Se(0)-protein conjugates are more toxic than selenium dioxide, sodium selenite, selenomethionine, or selenocystine. They are only minimally affected by a drug resistance mechanism, and they potentiate the cytotoxic effect of ionizing radiation and several standard chemotherapeutic agents. The cytotoxic mechanism of Se(0)-protein conjugates is not yet fully understood. Currently available data are consistent with the notion that Se(0)-protein conjugates act as air oxidation catalysts that cause a rapid depletion of intracellular glutathione and induce apoptosis. Drugs modeled after our Se(0)-protein conjugates may prove useful for the local and/or systemic therapy of cancer. 相似文献
88.
Wenk HR Lonardelli I Merkel S Miyagi L Pehl J Speziale S Tommaseo CE 《J Phys Condens Matter》2006,18(25):S933-S947
Diamond anvil cells may not only impose pressure upon a sample but also a compressive stress that produces elastic and plastic deformation of polycrystalline samples. The plastic deformation may result in texture development if the material deforms by slip or mechanical twinning, or if grains have a non-equiaxed shape. In radial diffraction geometry, texture is revealed by variation of intensity along Debye rings relative to the compression direction. Diffraction images (obtained by CCD or image plate) can be used to extract quantitative texture information. Currently the most elegant and powerful method is a modified Rietveld technique as implemented in the software package MAUD. From texture data one can evaluate the homogeneity of strain in a diamond anvil cell, the strain magnitude and deformation mechanisms, the latter by comparing observed texture patterns with results from polycrystal plasticity simulations. Some examples such as olivine, magnesiowuestite, MgSiO(3) perovskite and ε-iron are discussed. 相似文献
89.
Y. Ma S. Ajimura K. Aoki M. Dairaku Y. Y. Fu H. Fujioka T. Fukuda K. Futatsukawa K. Hosomi W. Imoto M. Kawai Y. Kakiguchi S. Kinoshita T. Koike N. Maruyama M. Mimori S. Minami Y. Miura K. Miwa Y. Miyagi T. Nagae D. Nakajima H. Noumi K. Shirotori T. Suzuki T. Takahashi T. N. Takahashi H. Tamura K. Tanida N. Terada A. Toyoda K. Tsukada M. Ukai S. H. Zhou 《The European Physical Journal A - Hadrons and Nuclei》2007,33(3):243-246
In this paper, a preliminary result from the latest hypernuclear γ -ray spectroscopy experiment (KEK-E566) is presented together
with a short discussion. The experiment was performed at the KEK-PS K6 beam line in 2005. In this experiment, the 12C(π+, K
+)12
ΛC reaction was employed to populate 12
ΛC/11
ΛB hypernuclei. A germanium detector array, Hyperball2, was constructed to detect γ -rays emitted from the hypernuclei produced.
Three hypernuclear γ -ray peaks were observed and assigned. 相似文献
90.
Flexible hollow-glass fibers with small-bore diameters of 250 and 320 mum have been developed for Er:YAG laser delivery. The fibers consist of a glass capillary tube and an inner coating of silver and polymer thin films that are deposited by use of a simple liquid-phase technique. The 250-mum-bore fiber exhibits a straight loss of 0.8 dB/m and a bending loss of 1.2 dB when it is bent 180 degrees at the output end, with a bending radius of 2 cm. The maximum energy delivered by the fibers is ~100 mJ. 相似文献