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401.
402.
Kazunori Mukasa Katsunori Imamura Iwao Shimotakahara Takeshi Yagi Kunio Kokura 《Journal of Optical and Fiber Communications Reports》2006,3(5):292-339
This paper gives an overview of IDF/RDF fiber design and development for submarine system. It starts with the concept of dispersion
management line and its difference from the conventional DCF used in a module. Then it reviews the fiber design details and
optical properties of various types of fibers used as parts of dispersion management lines. Fiber splicing issues using MFD
expanding method and a brief summary of transmission experiments using the dispersion management lines are also included.
Finally, we discussed a medial dispersion alternative comprising a positive and negative medial dispersion fiber and future
optical properties improvements possibilities. 相似文献
403.
404.
Masakazu Shimizu Noriyuki Ojima Hitoshi Ohnishi Tomoteru Shingaki Yasuyuki Hirakawa Tsutomu Masujima 《Analytical sciences》2003,19(1):49-53
MALDI-TOF mass spectrometry was used to detect intracellular molecules from a single intact cell on monolayers of other cells. Intracellular molecules, e.g., histamine, were gradually increased in a mouse bone marrow-derived mast cell by a maturation process. A single cell was captured by a microsuction pipette, and the mass spectra of intracellular histamine were measured directly. Finally, the time course of the intracellular molecular contents and the maturation stage from a single cell were estimated. 相似文献
405.
Md. Ashraf Ali Shuji Noguchi Miteki Watanabe Yasunori Iwao Shigeru Itai 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(10):743-747
7‐Ethyl‐10‐hydroxycamptothecin [systematic name: (4S)‐4,11‐diethyl‐4,9‐dihydroxy‐1H‐pyrano[3′,4′:6,7]indolizino[1,2‐b]quinoline‐3,14(4H,12H)‐dione, SN‐38] is an antitumour drug which exerts activity through the inhibition of topoisomerase I. The crystal structure of SN‐38 as the monohydrate, C22H20N2O5·H2O, reveals that it is a monoclinic crystal, with one SN‐38 molecule and one water molecule in the asymmetric unit. When the crystal is heated to 473 K, approximately 30% of SN‐38 is hydrolyzed at its lactone ring, resulting in the formation of the inactive carboxylate form. The molecular arrangement around the water molecule and the lactone ring of SN‐38 in the crystal structure suggests that SN‐38 is hydrolyzed by the water molecule at (x, y, z) nucleophilically attacking the carbonyl C atom of the lactone ring at (x − 1, y, z − 1). Hydrogen bonding around the water molecules and the lactone ring appears to promote this hydrolysis reaction: two carbonyl O atoms, which are hydrogen bonded as hydrogen‐bond acceptors to the water molecule at (x, y, z), might enhance the nucleophilicity of this water molecule, while the water molecule at (−x, y + , −z), which is hydrogen bonded as a hydrogen‐bond donor to the carbonyl O atom at (x − 1, y, z − 1), might enhance the electrophilicity of the carbonyl C atom. 相似文献
406.
We define a new concept of local states in the framework of algebraic quantum field theory (AQFT). Local states are a natural generalization of states and give a clear vision of localization in the context of QFT. In terms of them, we can find a condition from which follows automatically the famous DHR selection criterion in DHR-DR theory. As a result, we can understand the condition as consequences of physically natural state preparations in vacuum backgrounds. Furthermore, a theory of orthogonal decomposition of completely positive (CP) maps is developed. It unifies a theory of orthogonal decomposition of states and order structure theory of CP maps. Using it, localized version of sectors is formulated, which gives sector theory for local states with respect to general reference representations. 相似文献
407.
Rimiko Ozawa Takashi Hayashita Takahiro Matsui Chiaki Nakayama Akiyo Yamauchi Iwao Suzuki 《Journal of inclusion phenomena and macrocyclic chemistry》2008,60(3-4):253-261
N,N-Dimethyl-4-aminophenylboronic acid (DMAPB) showed pH-dependent dual fluorescence at 360 and 462 nm originating from locally
excited (LE) and twisted intramolecular charge transfer (TICT) states, respectively, in aqueous solutions. Upon complexation
with α-CD, LE fluorescence was markedly increased while TICT fluorescence was decreased. In contrast, both LE and TICT fluorescence
were increased when DMAPB was complexed with β-CD. The fluorescence variations enabled us to determine the 1:1 and 1:2 binding
constants of the DMAPB/α-CD complex to be 10 and 40 M−1, respectively, and the 1:1 binding constant of the DMAPB/β-CD complex to be 635 M−1. The dual fluorescence of DMAPB alone was found to be a good indicator of saccharide sensing. Under weakly alkaline conditions,
saccharides suppressed TICT fluorescence while increasing LE fluorescence. Among the saccharides investigated, d-fructose induced the largest fluorescence change, followed by d-ribose and d-glucose. This order is consistent with the stability of the boronate esters of DMAPB with saccharides. In the presence of
β-CD, saccharide selectivity was unchanged, while fluorescence was amplified. These results demonstrate the superiority of
the supramolecular DMAPB/β-CD complex to DMAPB alone as a ratiometric fluorescence sensor for saccharides in water. 相似文献
408.
Morita N Fukui K Irikuchi J Sato H Takano Y Okamoto I Ishibashi H Tamura O 《The Journal of organic chemistry》2008,73(18):7164-7174
Ethyl glyoxylate O-tert-butyldimethylsilyloxime (8), on treatment with 2.2 equiv of BF3 x OEt2, generated N-boranonitrone E, which underwent intermolecular cycloaddition with alkenes 18 to afford isoxazolidines 19 in moderate to high yields. The cycloaddition of N-boranonitrone E with most of the alkenes gave 3,5-trans isoxazolidines as the major isomers via a concerted mechanism. However, in the case of 1-methylated cyclic alkenes (18j and 18l), the cycloaddition surprisingly furnished the 3,3a-cis-cycloadducts (19j and 19l) as major isomers. A possible explanation is that the reaction of 1-methylated cyclic alkenes proceeds mainly via a stepwise mechanism. This reaction of terminal alkenes is very useful for synthesis of 1,3-anti aminoalcohol derivatives by reductive cleavage of an N-O bond. 相似文献
409.
Inada A Ogasawara R Koga I Nakatani N Inatomi Y Murata H Nishi M Nakanishi T 《Chemical & pharmaceutical bulletin》2008,56(5):727-729
Three novel furoquinoline alkaloid oxogeranyl ethers (1-3) and one known furoquinoline alkaloid (4) were isolated from the leaves of Boninia glabra, an endemic plant of the Bonin Islands. Their structures were elucidated on the basis of spectroscopic analysis. 相似文献
410.
Okamoto I Yamasaki R Sawamura M Kato T Nagayama N Takeya T Tamura O Masu H Azumaya I Yamaguchi K Kagechika H Tanatani A 《Organic letters》2007,9(26):5545-5547
We constructed a novel molecular conformational alteration system with an N-aryl-N-phenylacetamide structure, in which the N-aryl group consists of a hydroquinone-p-quinone system as a redox-dependent aromatic trigger. The amide conformation depended on the oxidation state of the aryl group, and the two states (compounds 2 and 3) were reversibly converted to each other by redox reactions. Such compounds would be applied as useful structural units for external stimulus-responsive control on the shape and function of large molecules or supramolecules. 相似文献