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101.
Chen YH Tai CY Kuo YH Kao CY Li JJ Hwang TL Fang LS Wang WH Sheu JH Sung PJ 《Chemical & pharmaceutical bulletin》2011,59(3):353-358
Five new eunicellin-type diterpenoids, cladieunicellins A-E (1-5), were isolated from an Indonesian soft coral identified as Cladiella sp. The structures of diterpenoids 1-5 were established using spectroscopic methods. Eunicellins 2 and 5 were found to be cytotoxic against DLD-1 and HL-60 tumor cells, respectively, and 3 displayed inhibitory effects against superoxide anion generation by human neutrophils. 相似文献
102.
Chien‐Chang Shen Chwan‐Fwu Lin Yu‐Ling Huang Shr‐Ting Wan Chin‐Chu Chen Sen‐Je Sheu Yi‐Chin Lin Chien‐Chih Chen 《中国化学会会志》2008,55(4):854-857
Three new compounds, 2,4‐dimethoxy‐6‐methylbenzene‐1,3‐diol ( 1 ), salmoquinone ( 2 ), and 3‐(4‐hydroxyphenyl)‐4‐isobutyl‐1H‐pyrrole‐2,5‐dione ( 3 ), together with six known compounds, 2‐methoxy‐6‐methyl‐p‐benzoquinone ( 4 ), 2,3‐dimethoxy‐5‐methyl‐p‐benzoquinone ( 5 ), 2‐hydroxy‐5‐methoxy‐3‐methyl‐p‐benzoquinone ( 6 ), eburcoic acid ( 7 ), fomefficinic acid C ( 8 ), and a pyrroledione ( 9 ), were isolated from the mycelium of Antrodia salmonea. The structures of these compounds were elucidated by spectrometric analyses including IR, NMR, and MS. Among these compounds, 4 and 5 exhibited cytotoxicity against KB, HepG2, and H2058 cell lines. 相似文献
103.
Mario J. Cazeca Ramaswamy Nagarajan Min‐Shyan Sheu Max Gow Cecil Comptois Ram W. Sabnis 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1317-1322
A plasma enhanced chemical vapor deposition (PECVD) reactor was used to deposit thin polymeric films with high absorption at 193 nm. The reactor is suitable to deposit uniform and pinhole free thin polymeric films with conformality over 95%. Conformal films with thickness as low as 200 Å have been deposited on silicon, glass, and quartz substrates, as well as silicon oxide, silicon nitrate, and aluminum films. Deposited films had variations in thickness of 3 to 5% over an area of 8 inches in diameter. Thin films deposited on silicon substrates under varying levels of RF power were scanned using the AFM technique. The measurements show increasing surface roughness of the scanned samples as the RF power increases. 相似文献
104.
Abstract Single crystals and polycrystalline samples of the compounds bis(1,3-di(p-n-octylphenyl)propane-l,3-dionato)copper(II) [I], and bis(l,3-di(p-n-octyloxy-phenyl)propane-l,3-dionato)copper(II) [II] have been studied by E.S.R. The E.S.R. spectra of single crystals of [I] at 298 K have the features associated with a spin 1/2 one-dimensional Heisenberg antiferromagnet while the spectra of single crystals of [II] do not. E.S.R. of single crystals of [I] and [II] provides a reliable means of detecting previously reported crystalline to discotic phase transitions. Single crystals of [I] heated beyond the temperature of the first discotic phase transition yield single line E.S.R. spectra which have an angular dependence and an asymmetric lineshape; these observations suggest that, in the discotic phase, exchange interactions are still significant and a degree of long range order is maintained. 相似文献
105.
Prof. Biing‐Chiau Tzeng Tsung‐Yi Chang Sheng‐Luen Wei Dr. Hwo‐Shuenn Sheu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(16):5105-5112
A 1D double‐zigzag framework, {[Zn(paps)2(H2O)2](ClO4)2}n ( 1 ; paps=N,N′‐bis(pyridylcarbonyl)‐4,4′‐diaminodiphenyl thioether), was synthesized by the reaction of Zn(ClO4)2 with paps. However, a similar reaction, except that dry solvents were used, led to the formation of a novel 2D polyrotaxane framework, [Zn(paps)2(ClO4)2]n ( 2 ). This difference relies on the fact that water coordinates to the ZnII ion in 1 , but ClO4? ion coordination is found in 2 . Notably, the structures can be interconverted by heating and grinding in the presence of moisture, and such a structural transformation can also be proven experimentally by powder and single‐crystal X‐ray diffraction studies. The related N,N′‐bis‐ (pyridylcarbonyl)‐4,4′‐diaminodiphenyl ether (papo) and N,N′‐(methylenedi‐para‐phenylene)bispyridine‐4‐carboxamide (papc) ligands were reacted with ZnII ions as well. When a similar reaction was performed with dry solvents, except that papo was used instead of paps, the product mixture contained mononuclear [Zn(papo)(CH3OH)4](ClO4)2 ( 5 ) and the polyrotaxane [Zn(papo)2(ClO4)2]n ( 4 ). From the powder XRD data, grinding this mixture in the presence of moisture resulted in total conversion to the pure double‐zigzag {[Zn(papo)2(H2O)2](ClO4)2}n ( 3 ) immediately. Upon heating 3 , the polyrotaxane framework of 4 was recovered. The double‐zigzag {[Zn(papc)2(H2O)2](ClO4)2}n ( 6 ) and polyrotaxane [Zn(papc)2(ClO4)2]n ( 7 ) were synthesized in a similar reaction. Although upon heating the double‐zigzag 6 undergoes structural transformation to give the polyrotaxane 7 , grinding solid 7 in the presence of moisture does not lead to the formation of 6 . Significantly, the bright emissions for double‐zigzag frameworks of 1 and 3 and weak ones for polyrotaxane frameworks of 2 and 4 also show interesting mechanochromic luminescence. 相似文献
106.
Atallah F. Ahmed Ming‐Hsuan Wu Yang‐Chang Wu Chang‐Feng Dai Jyh‐Horng Sheu 《中国化学会会志》2006,53(2):489-494
The metabolites, (24S)‐3β‐acetoxyergost‐5‐en‐21‐oic acid ( 2 ), 5′‐O‐acetylthymidine ( 3 ), 3′‐O‐acetylthymidine ( 4 ), and p‐vinylbenzyl alcohol ( 5 ), along with a known steroid ( 1 ) were isolated from the EtOAc extract of the Formosan soft coral Caldiella australis. The structures of new metabolites were determined on the basis of spectroscopic (including 1D and 2D NMR) analyses and by comparison of their NMR spectral data with those of related compounds. Except for 3 , all compounds exhibited cytotoxic activity of various degrees of potency against a limited panel of human liver and breast cancer cell lines. 相似文献
107.
Two novel briaranoidal derivatives, designated as briaexcavatins A (1) and B (2), along with two known metabolites, excavatolides B and C (3 and 4), were isolated from the octocoral Briareum excavatum. Both compounds 1 and 2 possess unprecedented 5,6-epoxy moiety in the 10-membered ring. Diterpenoid 1 possesses a novel pentacyclic skeleton with a ε-lactone. The structures of diterpenoids 1 and 2 were elucidated by interpretation of spectral data and the absolute stereochemistry was established by application of modified Mosher’s method on 3. 相似文献
108.
Horng Y. Tang Hsiao Y. Lin Ming Y. Liao Jean L. Liu Hwo S. Sheu 《Journal of solid state chemistry》2006,179(8):2728-2731
Bilayer hydrated Na0.35CoO2·1.3H2O structure has re-directed superconductivity research in recent years. Here, we develop a low temperature synthesis method to prepare a novel hydrous Cs0.2CoO2·0.63H2O compound in one step. The bilayer-hydrate of Cs0.2CoO2·0.63H2O with a greatest interlayer spacing d=10.0(2) Å among alkali cobalt oxides has been grown in crystal form. Magnetic susceptibility measurement of Cs0.2CoO2·0.63H2O displays a paramagnetic behavior down to 1.9 K. With the assistance of low temperature molten CsOH solvent, crystals of Rb0.30CoO2·0.36H2O and K0.35CoO2·0.4H2O can be grown. The results provide the capability for preparing a novel hydrous structure and the systematic investigation of interlayer coupling effect of alkali ion insertion compounds. 相似文献
109.
This paper presents a hybrid neuro-fuzzy methodology to identify appropriate global logistics (GL) operational modes used for global supply chain management. The proposed methodological framework includes three main developmental phases: (1) establishment of a GL strategic hierarchy, (2) formulation of GL-mode identification rules, and (3) development of a GL-mode choice model. By integrating advanced multi-criteria decision-making (MCDM) techniques including fuzzy analytical hierarchy process (Fuzzy-AHP), Fuzzy-MCDM, and the technique for order preference by similarity to an ideal solution (TOPSIS), six types of global logistics and operational modes coupled with corresponding fuzzy-based multi-criteria decision-making rules are specified in the second phase. Using the specified fuzzy decision-making rules as the input database, an adaptive neuro-fuzzy inference system (ANFIS) is then developed in the third phase to identify proper GL modes for the implementation of global supply chain management. A numerical study with a questionnaire survey database aimed at the information technology (IT) industries of Taiwan is conducted to illustrate the applicability of the proposed method. 相似文献
110.
Jyh-Chen Chen Gwo-Jiun Sheu Farn-Shiun Hwu Hsueh-I Chen Jinn-Kong Sheu Tsung-Xian Lee Ching-Cherng Sun 《Optical Review》2009,16(2):213-215
The effects of current distribution in LED chips on the electrical potential and optical light extraction efficiency are investigated
by a numerical simulation. The results show that when the resistivity of the current-spreading layer is decreased there is
current-crowding near the n-contact. On the other hand, when the resistivity in the current-spreading layer increases, there
is current-crowding near the p-contact. When the current is crowded near the n-contact due to less resistivity of the current-spreading
layer, the input power is lower because of the smaller series resistance in the chip, and the light extraction efficiency
is higher since the shadowing effect of the p-contact can be avoided. For L
p = 50 μm in this study, the light extraction efficiency at ρ
ITO = 0.1 × 10−3 Ω·cm is 1.4 times better than that when L
p = 100 μm, even though the driving voltage is raised 1.02 times. 相似文献