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Highly efficient nickel/phosphine catalyzed cross-couplings of diarylborinic acids with aryl tosylates and sulfamates

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Science China Chemistry 2014年第8期57卷 1126-1131页

作者： KE HaiHua CHEN XiaoFeng FENG YuanYuan zou gang Department of Fine Chemicals East China University of Science and Technology

Highly efficient cross-couplings of diarylborinic acids with aryl tosylates and sulfamates are reported for construction of biaryls using a tri(4-methoxyphenyl)phosphine-supported nickel catalyst system: Ni[P(4-MeOC6H4)3]2Cl2/2P(4-MeOC6H4)3 in the presence of K3PO4·3H2O in toluene. A variety of unsymmetrical biaryls could be obtained in good to excellent yields with1.5–3 mol% or 3–5 mol% catalyst loadings for aryl sulfamates and tosylates, respectively. In sharp contrast to the conventional nickel-catalyzed Suzuki coupling with arylboronic acids, arylsulfamates unexpectedly displayed a higher reactivity than the corresponding tosylates in coupling with diarylborinic acids catalyzed by the nickel/phosphine catalyst system.

关键词： nickel phosphine cross-coupling diarylborinic acid aryl tosylate aryl sulfamate

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Phosphorous Enrichment in Molten Adjusted Converter Slag:Part II Enrichment Behavior of Phosphorus in CaO-SiO_2-FeO_x-P_2O_5Molten Slag

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Journal of Iron and Steel Research International 2011年第12期18卷 22-26页

作者： WANG Nan LIANG Zhi-gang CHEN Min zou Zong-shu School of Materials and Metallurgy Northeastern University Shenyang 110819 Liaoning China

The enrichment behavior of phosphorus in CaO-SiO2-FeOx-P2O5 slag was studied by making an investigation on the distribution of phosphorous content in the CaO-SiO2-FeOx-P2O5 molten *** research results showed that the 2CaO·SiO2 solid particles existing in molten slag were the condensation sites for the phosphorus *** enrichment process of phosphorus in the molten slag can be recognized as three substeps：mass transfer of phosphorus from bulk slag to the surface of 2CaO·SiO2 particle,superficial solid solution reaction of phosphorus around the 2CaO·SiO2 particle,and diffusion of phosphorus through the product layer of 2CaO·SiO2-3CaO·P2O5 solid solution to the inner of 2CaO·SiO2 ***,higher temperature is favorable to the phosphorous enrichment from molten bulk slag to the 2CaO·SiO2 particles.

关键词： enrichment behavior phosphorus 2CaO·SiO2 particle mass transfer

Highly Selective Fluorescence Turn-on Chemosensor Based on Naphthalimide Derivatives for Detection of Trivalent Chromium Ions

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Chinese Journal of Chemistry 2012年第12期30卷 2844-2848页

作者： Chen Zhijun Wang Limin zou gang Teng Mingshuang Yu Jianjun Shanghai Key Laboratory of Functional Materials Chemistry and Institute of Fine Chemicals East China University of Science and Technology Shanghai 200237 China College of Chemistry & Materials Engineering Wenzhou University Wenzhou Zhejiang 325035 China

A new fluorescent probe, NPQ-C, was synthesized. NPQ-C was based on the naphthalimide derivatives and exhibited high selectivity and sensitivity for Cr3＋ ions. As a Cr3＋-amplified fluorescent probe, Its fluorescence spectrum showed 5.5-fold enhancement in the intensity of the signal at 500 nm on binding with the Cr3＋. Based on the fluorescence titration spectra and Job＇s-plot analysis, binding mode of NPQ-C with Cr3＋ was proposed. Fluorescence intensity was linear with concentration of Cr3＋ cation in a range from 0 to 10 μmol·L-1. NPQ-C was also sensitive for Cr3＋. The detection limit was calculated to be 0.20 pmol.L-1 which indicated that NPQ-C was sensitive to Cr3＋.

关键词： trivalent chromium ions fluorescent probe fluorescence enhancement high selectivity, high sensitivity

Entanglement of Non-symmetric Two Atomic Qubits Induced by a Coherent State Field

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Communications in Theoretical Physics 2006年第1期45卷 67-70页

作者： LI Jun-gang zou Jian CAI Jin-Fang SHAO Bin Department of Physics School of Science Beijing Institute of Technology Beijing 100081 China

The entanglement of two atomic qubits, which are coupled to a coherent state field with different couplings, is studied. The dynamical evolution of the concurrence, which measures the degree of the entanglement between the two qubits, is plotted versus the scaled time gt. It is found that the two qubits can be entangled by the coherent state field even when they are initially prepared in the most mixed state, and for very weak field, the most mixed state can be; more easily entangled than some pure states. It is also found that the entanglement between the qubits sensitively depends on the relative difference of the atomic couplings and the mean photon number of the field.

关键词： entanglement mixed state coherent state field

Phosphorous Enrichment in Molten Adjusted Converter Slag: Part I Effect of Adjusting Technological Conditions

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Journal of Iron and Steel Research International 2011年第11期18卷 17-19,39页

作者： WANG Nan LIANG Zhi-gang CHEN Min zou Zong-shu School of Materials and Metallurgy Northeastern University Shenyang 110819 Liaoning China

The effects of adjusting technological conditions on the phosphorous enrichment of adjusted converter slag were investigated. The results showed that the phosphorus could he effectively enriched to 2CaO · SiO2 and 2CaO · SiO2-3CaO· P2O5 solid solution （SS, namely phosphorus-rich phase） to be formed with the decreasing of basicity and cooling rate. Moreover, the morphology of the phosphorus-rich phase changed from granular for the original converter slag with higher basicity to the coexistence of granular shape and rod-like for the adjusted slag with lower basicity. P2 05 content in phosphorus-rich phase exceeded 30° while the hasicity was 1.3 at the cooling rate of 1.0 ℃/min.

关键词： phosphorous enrichment adjusting technological condition adjusted converter slag phosphorus-richphase

Fatigue Strength Improvement of Welded Joint by Ultrasonic Peening in Ultra-Fine Grain Steel

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Journal of Iron and Steel Research International 2003年第3期10卷 64-66页

作者： TIAN Zhi-ling zou gang HE Chang-hong ZHANG Xiao-mu Central Iron and Steel Research Institute

The influence of rare earths (RE) on carbides in high carbon steel weld metal was studied by transmission electron microscope (TEM) and energy dispersive X ray microanalysis (EDX). It is found that rare earth markedly affects the quantity, morphology and distribution of carbides. The precipitating mechanism of carbides was proposed in which rare earth compounds with high surface energy serve as the nucleation sites for carbides in superheated liquid metal and the induced carbides are precipitated extensively and distributed evenly. The preferential precipitation of carbides decreases the carbon content in matrix, which is transformed into low carbon lath martensite after welds are chilled to room temperature.

关键词： rare earth metal carbide weld

One-pot synthesis of 7-bromo-1-[4-(1-cyano-1-methylethyl)]-phenyl-[1,2,4]-triazole-[4,3-a]-quinoxalin

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Chinese Chemical Letters 2009年第1期20卷 52-54页

作者： Yan Yang Hong gang Hu Qing Jie Zhao Shi Chong Yu Zhi gang Dan Yan zou Qiu Ye Wu Department of Organic Chemistry School of Pharmacy Second Military Medical University Shanghai 200433 China

[1,2,4]-Triazole-[4,3-a]-quinoxaline is an important component of many drugs. The yield of the reported methods for triazole cyclization step was usually as low as 20%. In this article, the triazole cyclization step w... 详细信息

关键词： -Triazole-[4,3-a]-quinoxaline Microwave Synthesis

Spatial and spectral filtering of tapered lasers by using tapered distributed Bragg reflector grating

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Chinese Physics B 2022年第8期31卷 405-409页

作者： Jing-Jing Yang Jie Fan Yong-gang zou Hai-Zhu Wang Xiao-Hui Ma State Key Laboratory of High Power Semiconductor Laser Changchun University of Science and TechnologyChangchun 130022China

A 1040 nm tapered laser with tapered distributed Bragg reflector(DBR) grating is designed and fabricated. By designing the grating with tapered layout, the tapered DBR grating exhibits the scattering effect on side backward-traveling waves, thus achieving additional suppression of parasitic oscillation. Under the suppression of parasitic oscillation, the spatial and spectral characteristics of the tapered laser are improved. The experimental results show that a near-Gaussian far-field distribution and a kink-free P–I characteristics are achieved, and a single peak emission with a wavelength of1046.84 nm and a linewidth of 56 pm is obtained.

关键词： tapered lasers distributed Bragg reflector backward-traveling wave parasitic oscillation

Polarization control and tuning efficiency of tunable vertical-cavity surface-emitting laser with internal-cavity sub-wavelength grating

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Chinese Physics B 2020年第8期29卷 310-316页

作者： Xiao-Long Wang Yong-gang zou Zhi-Fang He Guo-Jun Liu Xiao-Hui Ma State Key Laboratory of High-Power Laser Diodes Changchun University of Science and TechnologyChangchun 130022China

We design an 850 nm tunable vertical-cavity surface-emitting laser(VCSEL)structure using an internal-cavity sub-wavelength *** use of such a tuning structure allows for wider wavelength tuning range and more stable single-polarization as compared to conventional tunable *** features of the internal-cavity grating effect on the wavelength tuning and polarization characteristics of the tunable VCSEL are *** simulation results show that the largest wavelength tuning range achieves 44.2 nm,and the maximum orthogonal polarization suppression ratio(OPSR)is 33.4 dB(TE-type)and 38.7 dB(TM-type).

关键词： sub-wavelength grating polarization mode tunable VCSEL wavelength tuning