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531.
Dr. Molly Meng-Jung Li Dr. Hanbo Zou Dr. Jianwei Zheng Dr. Tai-Sing Wu Dr. Ting-Shan Chan Prof. Yun-Liang Soo Dr. Xin-Ping Wu Prof. Xue-Qing Gong Tianyi Chen Dr. Kanak Roy Prof. Georg Held Prof. Shik Chi Edman Tsang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):16173-16180
There is increasing interest in capturing H2 generated from renewables with CO2 to produce methanol. However, renewable hydrogen production is expensive and in limited quantity compared to CO2. Excess CO2 and limited H2 in the feedstock gas is not favorable for CO2 hydrogenation to methanol, causing low activity and poor methanol selectivity. Now, a class of Rh-In catalysts with optimal adsorption properties to the intermediates of methanol production is presented. The Rh-In catalyst can effectively catalyze methanol synthesis but inhibit the reverse water-gas shift reaction under H2-deficient gas flow and shows the best competitive methanol productivity under industrially applicable conditions in comparison with reported values. This work demonstrates a strong potential of Rh-In bimetallic composition, from which a convenient methanol synthesis based on flexible feedstock compositions (such as H2/CO2 from biomass derivatives) with lower energy cost can be established. 相似文献
532.
Chi Yan Wong F. W. Tong Zhenzhou Cheng Ke Xu Yi Min Chen Hon Ki Tsang 《Applied physics. B, Lasers and optics》2014,114(3):367-371
We propose and demonstrate a multiwavelength erbium-doped fiber laser stabilized by four-wave mixing (FWM) in a nonlinear silicon-on-insulator (SOI) waveguide. The optical gain was provided by an erbium-doped fiber amplifier, and the wavelength selectivity was achieved by a Fabry–Pérot comb filter in the ring cavity. The FWM in the SOI waveguide was enhanced by applying a reverse-biased p-i-n diode structure to reduce free-carrier absorption. Making use of the nonlinearity of the SOI waveguide, a multiwavelength laser with six output wavelengths at 0.8 nm spacing was achieved. The power difference among modes was equalized within a range of 1.8 dB. The power fluctuation of each mode was stabilized to <0.65 dB during 20 min observation at room temperature. 相似文献
533.
M.B. Tsang Z. ChajeckiD. Coupland P. DanielewiczF. Famiano R. HodgesM. Kilburn F. LuW.G. Lynch J. WinkelbauerM. Youngs Y.X. Zhang 《Progress in Particle and Nuclear Physics》2011,66(2):400-404
Constraints on the equation of state (EoS) for symmetric matter (equal neutron and proton numbers) have been extracted from energetic collisions of heavy ions over a range of energies. Collisions of neutron-deficient and neutron-rich heavy ions now provide initial constraints on the EoS of neutron-rich matter at subsaturation densities from isospin diffusions and neutron proton ratios. This article reviews the experimental constraints on the density dependence of symmetry energy at subsaturation density. 相似文献
534.
Yan-Qiu Che Jiang Wang Shi-Gang Cui Bin Deng Xi-Le Wei Wai-Lok Chan Kai-Ming Tsang 《Nonlinear Analysis: Real World Applications》2011,12(6):3199-3206
In this paper, an adaptive neural network (NN) sliding mode controller (SMC) is proposed to realize the chaos synchronization of two gap junction coupled FitzHugh–Nagumo (FHN) neurons under external electrical stimulation. The controller consists of a radial basis function (RBF) NN and an SMC. After the RBFNN approximating the uncertain nonlinear part of the error dynamical system, the SMC realizes the desired control property regardless of the existence of the approximation errors and external disturbances. The weights of the NN are tuned online based on the sliding mode reaching law. According to the Lyapunov stability theory, the stability of the closed error system is guaranteed. The control scheme is robust to the uncertainties such as approximate error, ionic channel noise and external disturbances. Chaos synchronization is obtained by the proper choice of the control parameters. The simulation results demonstrate the effectiveness of the proposed control method. 相似文献
535.
Chia‐Yun Liu Dr. Ming‐Tsang Tsai Dr. Po‐Yu Tsai Yu‐Ting Liu Si Ying Chen Prof. Agnes Hsiu Hwa Chang Prof. King‐Chuen Lin 《Chemphyschem》2011,12(1):206-216
By employing time‐resolved Fourier transform infrared emission spectroscopy, the fragments HCl (v=1–3), HBr (v=1), and CO (v=1‐3) are detected in one‐photon dissociation of 2‐bromopropionyl chloride (CH3CHBrCOCl) at 248 nm. Ar gas is added to induce internal conversion and to enhance the fragment yields. The time‐resolved high‐resolution spectra of HCl and CO were analyzed to determine the rovibrational energy deposition of 10.0±0.2 and 7.4±0.6 kcal mol?1, respectively, while the rotational energy in HBr is evaluated to be 0.9±0.1 kcal mol?1. The branching ratio of HCl(v>0)/HBr(v>0) is estimated to be 1:0.53. The bond selectivity of halide formation in the photolysis follows the same trend as the halogen atom elimination. The probability of HCl contribution from a hot Cl reaction with the precursor is negligible according to the measurements of HCl amount by adding an active reagent, Br2, in the system. The HCl elimination channel under Ar addition is verified to be slower by two orders of magnitude than the Cl elimination channel. With the aid of ab initio calculations, the observed fragments are dissociated from the hot ground state CH3CHBrCOCl. A two‐body dissociation channel is favored leading to either HCl+CH3CBrCO or HBr+CH2CHCOCl, in which the CH3CBrCO moiety may further undergo secondary dissociation to release CO. 相似文献
536.
Ye L Wang Y Chen X Yue B Tsang SC He H 《Chemical communications (Cambridge, England)》2011,47(26):7389-7391
Three-dimensionally ordered mesoporous Pd networks fabricated by a simple reduction method in solution using a face centered cubic silica super crystal as template exhibit high electroactivity in formic acid oxidation. 相似文献
537.
Qian J Klomsiri C Wright MW King SB Tsang AW Poole LB Furdui CM 《Chemical communications (Cambridge, England)》2011,47(32):9203-9205
Facile, two-step synthesis and kinetic characterization of new chemical probes for selective labeling of sulfenic acid (-SOH) in proteins are presented. The synthesis route relies on the simple and highly efficient Michael addition of thiol containing tags or linkers to 4-cyclopentene-1,3-dione, the unsaturated derivative of 1,3-cyclopentanedione. 相似文献
538.
Gu Z Shen P Tsang SW Tao Y Zhao B Tang P Nie Y Fang Y Tan S 《Chemical communications (Cambridge, England)》2011,47(33):9381-9383
A new benzodithiophene-based copolymer PTG1 with dithienylbenzothiadiazole-vinylene side chains exhibits excellent film-forming ability, a deep HOMO energy level, and a good miscibility with PC(71)BM. Bulk heterojunction polymer solar cells fabricated from PTG1 and PC(71)BM showed a promising power conversion efficiency over 4.0%. 相似文献
539.
Tao Yu Daniel Ping‐Kuen Tsang Dr. Vonika Ka‐Man Au Dr. Wai Han Lam Dr. Mei‐Yee Chan Prof. Dr. Vivian Wing‐Wah Yam 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(40):13418-13427
A series of triarylamine‐containing tricarbonyl rhenium(I) complexes, [BrRe(CO)3(N^N)] (N^N=5,5′‐bis(N,N‐diaryl‐4‐[ethen‐1‐yl]‐aniline)‐2,2′‐bipyridine), has been designed and synthesized by introducing a rhenium(I) metal center into a donor‐π‐acceptor‐π‐donor structure. All of the complexes showed an intense broad structureless emission band in dichloromethane at around 680–708 nm, which originated from an excited state of intraligand charge transfer (3ILCT) character from the triarylamine to the bipyridine moiety. Upon introduction of the bulky and electron‐donating pentaphenylbenzene units attached to the aniline groups, the emission bands were found to be red shifted. The nanosecond transient absorption spectra of two selected complexes were studied, which were suggestive of the formation of an initial charge‐separated state. Computational studies have been performed to provide further insight into the origin of the absorption and emission. One of the rhenium(I) complexes has been utilized in the fabrication of organic light‐emitting diodes (OLEDs), representing the first example of the realization of deep red to near‐infrared rhenium(I)‐based OLEDs with an emission extending up to 800 nm. 相似文献
540.
You Y Uboh CE Soma LR Guan F Li X Liu Y Rudy JA Chen J Tsang D 《Journal of chromatography. A》2011,1218(26):3982-3993
The potential for using testosterone and nandrolone esters in racehorses to boost the biological concentrations of these steroids and enhance athletic performance is very compelling and should be seriously considered in formulating regulatory policies for doping control. In order to regulate the use of these esters in racehorses, a sensitive and validated method is needed. In this paper, we report such a method for simultaneous separation, screening, quantification and confirmation of 16 testosterone and nandrolone esters in equine plasma by ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Analytes were extracted from equine plasma by liquid-liquid extraction using a mixture of methyl tert-butyl ether and ethyl acetate (50:50, v/v) and separated on a sub-2 micron C(18) column. Detection of analytes was achieved on a triple-quadrupole mass spectrometer by positive electrospray ionization mode with selected reaction monitoring (SRM). Mobile phase comprised 2 mM ammonium formate and methanol. Deuterium-labeled testosterone enanthate and testosterone undecanoate were used as dual-internal standards for quantification. Limits of detection (LOD) and quantification (LOQ) were 25-100 pg/mL and 100-200 pg/mL, respectively. The linear dynamic range of quantification was 100-10,000 pg/mL. For confirmation of the presence of these analytes in equine plasma, matching of the retention time with mass spectrometric ion ratios from MS/MS product ions was used. The limit of confirmation (LOC) was 100-500 pg/mL. The method is sensitive, robust, selective and reliably reproducible. 相似文献