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111.
A versatile palladium catalyst system for Suzuki-Miyaura coupling of alkenyl tosylates and mesylates
Wong PY Chow WK Chung KH So CM Lau CP Kwong FY 《Chemical communications (Cambridge, England)》2011,47(29):8328-8330
A general and effective palladium system for Suzuki-Miyaura coupling of alkenyl electrophiles under mild reaction conditions is reported. With the Pd(OAc)(2)/CM-phos system, a variety of alkenyl tosylates are coupled well with ArB(OH)(2). Moreover, the first successful examples of using alkenyl mesylates in alkenylation are also described. 相似文献
112.
K. A. Pericleous M. Cross G. Moran P. Chow K. S. Chan 《Advances in Computational Mathematics》1996,6(1):295-308
A mathematical model to analyse some key aspects of the metal cast process is described involving the filling of the mould by liquid metal and simultaneously, undergoing both cooling and solidification (re-melting) phase change. A computational solution procedure based upon a finite volume discretisation approach, on both structured and unstructured meshes, is described. The overall flow solution procedure is based on the pressure correction algorithm SIMPLE suitably adapted to: (a) solve for the free surface with minimal smearing by the SEA algorithm, and (b) solve for the solidification/melting phase change using an enthalpy conservation algorithm developed by Voller, but with its root in the work of Crank many years ago.Dedicated to Professor J. Crank on the occasion of his 80th birthday 相似文献
113.
Changqing Q Wang Y.T Chow W.A Gambling Duorong Yuan Dong Xu Guanghui Zhang Mingguo Liu Minhua Jiang 《Optics & Laser Technology》1998,30(5):291-293
We report the intracavity-frequency-doubling of a 946 nm Nd:YAG laser with a CMTC crystal at room temperature. A cw output power of 1.64 mW of blue light at 473 nm is obtained. To our knowledge, this is the first time that CMTC crystal has been used to frequency double a 946 nm Nd:YAG laser. 相似文献
114.
Monodisperse Au-silicate nanoparticles (10.7±1.6 nm in diameter) were prepared by reduction of aqueous solution containing
2 mM HAuCl4 with sodium citrate (1 wt.%) in a hydrosol, in which small clusters of silicate formed by hydrolysis and polymerization of
3-aminopropyltrimethoxysilane (APTMS). APTMS covalently linked to reduced gold particles through its -NH2 end-group. UV-vis spectra of the obtained Au-silicate nanoparticles showed a peak at ∼690 nm due to the interface effects
between the Au and the silicate matrix. The Au-silicate nanoparticles exhibited near-IR (NIR) sensitivity. Cytotoxicity and
limited hemocompatibility in vitro for the prepared Au-silicate nanoparticles were also investigated. It was shown that at lower concentration (<1 μg/ml), the
Au-silicate nanoparticles were biocompatible without causing any cytotoxicity and hemolysis. 相似文献
115.
116.
K.H. Chow Th. Jestädt S.J. Blundell S.R. Dunsiger W. Hayes B. Hitti M.A. Green R.F. Kiefl J.E. Millburn P.A. Pattenden F.L. Pratt M.J. Rosseinsky 《Hyperfine Interactions》1997,104(1-4):55-60
We report μSR measurements on a series of compounds with composition La2-xSrxNiO4+\delta where the net hole concentration x+2\delta is greater than 0.4. A magnetic transition is found in all the samples studied
which occurs at a composition‐dependent temperature TM. Below TM, clear precession signals are observed in zero applied magnetic field. The possible muon sites are discussed within the context
of dipole‐field calculations.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
117.
David M. Walba Charles A. Liberko Eva Korblova Matthew Farrow Thomas E. Furtak Bruce C. Chow Daniel K. Schwartz Adam S. Freeman Kenneth Douglas Scott D. Williams Arthur F. Klittnick Noel A. Clark 《Liquid crystals》2004,31(4):481-489
A simple procedure for the preparation of octadecylsiloxane self-assembled monolayers (SAMs) on float glass substrates is described. The method utilizes commercial octadecyltriethoxysilane, OTE: n-C18H37Si(OCH2CH3)3, as the SAM precursor, with deposition accomplished in toluene solution using n-butylamine as catalyst. This synthetic approach obviates the use of the problematic trichlorosilanes typically required for the preparation of high quality SAMs, and is characterized by a wide 'process window,' utilizing off-the-shelf reagents without special handling. 相似文献
118.
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120.
R.L. Lichti S.F.J. Cox C. Schwab T.L. Estle B. Hitti K.H. Chow 《Hyperfine Interactions》1997,105(1-4):333-338
Transverse and zero‐field muon spin relaxation reveal several diamagnetic muonium states in InP characterized by their static
linewidths and diffusion properties. We tentatively associate low‐temperature diamagnetic states with Mu+ in the BC and TP interstitial sites and a missing fraction with Mu0 rapidly diffusing through TIn interstices. Trapping peaks above 250 K imply static centers which depend on doping type, consistent with Mu- at TIn for n‐type samples and Mu coupled with a dopant or other defect for p‐type.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献