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11.
Tien-Yau Luh 《Journal of organometallic chemistry》1979,174(2):169-172
Thermal decomposition of dicyclopentadienone in the presence of M(CO)6 (M = Cr, Mo, W) yields indanone. 2-Bromocyclopentadienone dimer, on the other hand, affords 4-bromoindanone under the same conditions. Nocorresponding organometallic complexes were isolated. The mechanismof this reaction is discussed. 相似文献
12.
Tseng JC Huang SL Lin CL Lin HC Jin BY Chen CY Yu JK Chou PT Luh TY 《Organic letters》2003,5(23):4381-4384
[structure: see text] Furan-containing oligoaryl cyclophanene 1 and the corresponding cyclophane 2 were synthesized from propargylic dithioacetal 3. The electrochemical and photophysical properties and the fluxional behavior of these molecules have been examined. The emission of 1 appeared at 499 nm whereas that of 2 appeared at 389 nm. 相似文献
13.
Zhi‐Chang Liu Dr. Chih‐Hsien Chen Dr. Hsian‐Wen Wang Yen‐Chin Huang Ming‐Jui Kao Tsong‐Shin Lim Prof. Tien‐Yau Luh Prof. 《化学:亚洲杂志》2010,5(6):1425-1438
Polynorbornenes appended with porphyrins containing a range of different linkers are synthesized. The use of bisamidic chiral alanine linkers between the pending porphyrins and the polymeric backbone has been shown to bring the adjacent porphyrin chromophores to more suitable orientation for exciton coupling owing to hydrogen bonding between the adjacent linkers. The hydrogen bonding between the adjacent pendants in these polymers may induce a cooperative effect and therefore render single‐handed helical structures for these polymers. Such a cooperative effect is reflected in the enhancement of FRET efficiencies between zinc–porphyrin and free base porphyrin in random copolymers. 相似文献
14.
In this paper, we study a Ck/Cm/1/N open queueing system with finite capacity. We investigate the property which shows that a product of the Laplace Stieltjes Transforms of interarrival and service times distributions satisfies an equation of a simple form. According to this equation, we present that the stationary probabilities on the unboundary states can be written as a linear combination of vector product-forms. Each component of these products is expressed in terms of roots of an associated characteristic polynomial. As a result, we carry out an algorithm for solving stationary probabilities in Ck/Cm/1/N systems, which is independent of N, hence greatly reducing the computational complexity. 相似文献
15.
We prove the existence of entire functions which are universal under translations and bounded on certain prescribed sets.
It is also shown that the family of all these universal functions is a dense but not a Gδ-subset in the space of entire functions provided with a natural metric.
Received: 24 November 2004; revised: 12 April 2005 相似文献
16.
17.
The A2Π - X2Σ+ electronic transition of MgH has been studied by the laser excitation spectroscopy. Some new transitions have been observed for the first time. Rotational parameters of the X and A state have been derived and compared with other experimental values. 相似文献
18.
Sundarraj Sudhakar Jui-Hung Hsu Yi-Hung Liu Yu Wang Ding-Shyue Yang Bih-Yaw Jin Tien-Yau Luh 《Silicon Chemistry》2002,1(5-6):403-407
Novel siloxane tethered para divinylarene cyclophanes, containing phenyl, biphenyl and naphthalene rings as the aromatic nuclei, were prepared by the hydrolytic condensation of the corresponding bis{[dimethyl(i-propoxy)silyl]vinyl}arenes under basic conditions.The photophysics of the cyclophanes were investigated using UV and fluorescence spectroscopy. 相似文献
19.
Let
be the family of all compact sets in
which have connected complement. For K ε M we denote by A(K) the set of all functions which are continuous on K and holomorphic in its interior.Suppose that {zn} is any unbounded sequence of complex numbers and let Q be a given sub-sequence of
0.If Q has density Δ(Q) = 1 then there exists a universal entire function with lacunary power series
- 1. (1) (z) = ε∞v = 0 vZv, v = 0 for v Q, which has for all K ε M the following properties simultaneously
- 2. (2) the sequence {(Z + Zn)} is dense in A(K)
- 3. (3) the sequence { (ZZn)} is dense in A(K) if 0 K.
20.
Jun Xu Ze Zhang Yi-Hung Liu Qingxiang Guo Guan-Wu Wang Guoqiao Lai Tien-Yau Luh 《Journal of polymer science. Part A, Polymer chemistry》2017,55(18):2999-3010
Eight ladderphanes with C2-symmetric planar chiral ferrocene linkers are synthesized by ring opening metathesis polymerization of bisnorbornene monomers using Grubbs-I catalyst. The aminobenzoate in both monomers and polymers shows absorption maximum around 320 nm. Both monomers and polymers are Circular dichroism (CD) active. Little enhancements of CD profiles around 320 nm are observed for ladderphanes having chiral chloro- or phenyl-substituted ferrocene linkers. However, ladderphanes with a phenyl substituent on the cyclopendienyl ring exhibits enhancement of CD curves aound 240–300 nm. The congested phenyl moieties in adjacent linkers in this polymer might be well oriented such that interactions between these aromatic substituents on different monomeric units might provoke the enhancement of the CD curves in this region. When the methyl-substituted cyclopendienyl ligand is used for chiral ferrocene linkers, the ladderphanes exhibit two-fold enhancement of CD spectrum around 320 nm. This enhancement is further increased when the cyclopentadienyl ligand contains an additional phenyl substituent, owing to exciton coupling between aminobenzoate moieties in adjacent monomeric units. Moreover, the intensity of the CD curves in the region of 240–300 nm is significantly increased. These results suggest that the later polymer may adopt a posible helical structure. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2999–3010 相似文献