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1.
This paper considers two models of BASIC mode data transmission: When we transmit data with length l
- 1. (1) data are divided into N blocks and each block is transmitted individually
- 2. (2) data are divided into N sub-blocks and all sub-blocks are transmitted together.
2.
3.
4.
Noboru Matsumura Motoyuki Kusamiya Hiroo Inoue Masanori Yasui Fujiko Iwasaki 《Journal of heterocyclic chemistry》1995,32(4):1269-1275
1,3-Bis(p-substituted-phenylthiocarbamoyl)-2-imidazolidinethiones 3a-f reacted with bromine to give trithiadiazapentalene derivatives 5a-f , bearing the exocyclic C-N double bonds, in moderate yields. The molecular structure of 5b was elucidated by the X-ray crystallographic analysis. The treatment of 5b-f with hydrochloric acid gave the ring-opening products, 1,3-bis(p-substituted-phenylthiocarbamoyl)-2-imidazo-lidinones 9b-f , accompanied by the production of elemental sulfur. Reduction of 5b , 5d , and 5e with sodium borohydride gave the ring-opening compounds, 1,3-bis(p-substituted-phenylthiocarbamoyl)-2-imidazolidines 13b , 13d , and 13e respectively. 相似文献
5.
Jingye Li Fumihiro Muto Akihiro Oshima Masakazu Washio Shigetoshi Ikeda Yoneho Tabata Chihiro Matsuura 《European Polymer Journal》2006,42(6):1222-1228
New proton exchange membranes (PEMs) were prepared by pre-irradiation induced grafting of α-methylstyrene (AMS)/styrene (STY)/divinylbenzene (DVB) into the crosslinked polytetrafluoroethylene (RX-PTFE) films and successively sulfonated. The new PEMs showed the improved glass transition temperature and chemical stability as compared with the PEMs prepared by pre-irradiation induced grafting of STY/DVB. The balance of the cost, grafting kinetic, thermal properties and the properties of the resulted proton exchange membrane is the key point of this work. 相似文献
6.
Yasuyuki Takeda Chihiro Takagi 《Journal of inclusion phenomena and macrocyclic chemistry》1994,17(1):93-97
The theory is derived to determine the dimer-formation constant,K
2, of a crown ethermetal salt 111 complex in organic solvents of low dielectric constant by solvent extraction. The theoretical predictions are verified experimentally by extraction of sodium picrate (NaA) with 15-crown-5 (15C5) into carbon tetrachloride. All the experiments were conducted at 25°C. The logK
2 value of the Na(15C5)A complex in carbon tetrachloride has been determined to be 4.05±0.11. Moreover, the partition constant of the complex is calculated. 相似文献
7.
Let II be a translation plane of orderq
3, with kernel
GF(q) forq a prime power, that admits a collineation groupG of orderq
3 in the linear translation complement. Moreover, assume thatG fixes a point at infinity, acts transitively on the remaining points at infinity andG/E is an abelian group of orderq
2, whereE is the elation group ofG.In this article, we determined all such translation planes. They are (i) elusive planes of type I or II or (ii) desirable planes.Furthermore, we completely determined the translation planes of orderp
3, forp a prime, admitting a collineation groupG of orderp
3 in the translation complement such thatG fixes a point at infinity and acts transitively on the remaining points at infinity. They are (i) semifield planes of orderp
3 or (ii) the Sherk plane of order 27. 相似文献
8.
Chihiro Tsukano 《Tetrahedron letters》2006,47(38):6803-6807
The structural elements required for cytotoxicity of gymnocin-A, a polycyclic ether isolated from the red tide-forming dinoflagellate, Karenia mikimotoi, were investigated by the total synthesis and evaluation of the structural analogues. The results of the structure-activity relationship studies indicated that the α,β-unsaturated aldehyde functionality of the side chain as well as the molecular length were needed for exhibiting the cytotoxicity of gymnocin-A. 相似文献
9.
M Mitsukuchi J Nakagami T Ikemoto S Higuchi Y Tarumoto H Yasui K Sota 《Chemical & pharmaceutical bulletin》1989,37(6):1534-1539
A series of 17-succinyl derivatives of four corticosteroids was prepared. They were tested for vasoconstrictive activity in humans, using 9 alpha-fluoro-11 beta, 21-dihydroxy-16 beta-methyl-17 alpha-valeryloxy-1,4-pregnadiene-3,20-dione (betamethasone 17-valerate, BV) as a standard. The activities of the 21-chloro 17-methylsuccinate compounds (6A, 6C and 6D) were greater than that of BV. A structure-activity relationship study showed that the activities of the 21-chloro 17-methylsuccinates were more potent than those of the corresponding 21-esters. 相似文献
10.
Ichimin Shirotani Yousuke Shimaya Chihiro Sekine 《Journal of solid state chemistry》2003,174(1):32-34
New filled skutterudites with heavy lanthanide, LnFe4P12 (Ln=Tb, Dy, Ho, Er, Tm, Yb, Lu and Y) have systematically been prepared for the first time by the high-pressure technique. The relationship between lattice constants and atomic numbers of lanthanide (including Y) is established for LnFe4P12. Electrical and magnetic properties of several new filled skutterudites with heavy lanthanide have been studied at low temperatures; YFe4P12 shows a superconducting transition at around 7 K, and DyFe4P12 behaves as a ferromagnet below 10 K. Electrical and magnetic anomalies in DyFe4P12 and YFe4P12 are mainly discussed. 相似文献