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The design and synthesis of fused thiophenes and their applications in organic field-effect transistors

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Science China Chemistry 2010年第4期53卷 779-791页

作者： LIU Ying, YU Gui & LIU YunQi beijing {1. laboratory for molecular Sciences, Key laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, beijing 1.01.0, China 1. beijing {1. laboratory for molecular Sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

Fused thiophenes refer to oligothienoacenes in which several thiophenes are coupled together via twoor multi-positions and their derivatives. The synthesized organic semiconductors based on fused thiophenes exhibit excellent field effect properties due to their efficient intermolecular S…S interactions and π…π stacking. The performances of organic field-effect transistors (OFETs) depend not only on the materials but also on the devices. Such factors which influence the device performances as device structures, fabrication technologies and interface engineering are extensively investigated based on the fused thiophenes. Searching for new organic semiconductors and improving the device fabrication technologies are two major issues in the development of OFETs.

关键词： fused thiophenes oligothienoacenes organic field-effect transistors device performance

Eavesdropping in a quantum secret sharing protocol based on Grover algorithm and its solution

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Science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 491-495页

作者： HAO Liang1. LI JunLin1.& LONG GuiLu1.2 1.ey laboratory for Atomic and {1. NanoSciences and Department of Physics, Tsinghua University, beijing 1.0084, China 2Tsinghua national laboratory for Information Science and Technology, beijing 1.0084, China 1. Key laboratory for Atomic and {1. NanoSciences and Department of Physics Tsinghua University Beijing 100084 China2. Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China

A detailed analysis has showed that the quantum secret sharing protocol based on the Grover algorithm (Phys Rev A, 2003, 68: 022306) is insecure. A dishonest receiver may obtain the full information without being detected. A quantum secret-sharing protocol is presents here, which mends the security loophole of the original secret-sharing protocol, and doubles the information capacity.

关键词： quantum secret sharing Grover algorithm quantum cryptography quantum search algorithm

Density functional theory study of the reaction paths of reactions of CH3C（O）O2 radicals with HO2 in the gas phase

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Progress in Natural Science:Materials International 2006年第12期16卷 1269-1274页

作者： ZHOU Yuzhi~ 1.2 , ZHANG Shaowen~1.and LI Qianshu~1.*(1. State Key laboratory of Explosion Science and Technology, {1. Institute of Technology, {1. 1.0081. China 2. {1. Institute of Education, {1. 1.0044, China) [a]State Key laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing China [b]beijing Institute of Education Beijing China

A DFT study on the reactions between CH_3C（O）O_2and HO_2radicals has been carried out. It is suggested that both the triplet and singlet potential surfaces involve a complex mechanism with the formation of loosely bound intermediate complexes of reactants and products. The reaction prefers to occur on the triplet surface to produce peracetic acid (CH_3C（O）O_2H) and triplet O_2molecule. The CH_3C（O）O_2H can further convert into CH_3C（O）O and HO radicals.

关键词： acetyl peroxy radicals HO2 radicals reaction mechanism DFT.

Photogeneration of the free radicals and singlet oxygen by chrysophanol from rheum

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Science China Chemistry 2004年第5期47卷 381-387页

作者： RAO Jing1.2, XIE Jie1. ZHAO Jingquan1.& ZHU Teng2 1. Key laboratory of Photochemistry, Center for {1. Science, Institute of Chemistry, The Chinese Academy of Sciences, beijing 1.0080, China 2. University of Science and Technology beijing, beijing 1.083, China 1. Key laboratory of Photochemistry Center for Molecular Science Institute of Chemistry The Chinese Academy of Sciences 100080 Beijing China 2. University of Science and Technology beijing 10083 Beijing China

In the current work, chryosphanol (MHAQ) was isolated and purified from rheum, and the photosensitization activities were studied. In nitrogen-saturated DMSO solution, irradia- tion of chryosphanol (MHAQ) with visible light (>430 nm) produced the semiquinone radical anions (MHAQ??), which was intensified significantly by an electron donor NADH, suggesting electron transfer between the excited and ground state photosensitizer molecules. In an air-saturated DMSO solution, superoxide radical anions (O2 ), trapped by DMPO, were detected. ?? It was proved that O2 was not originated from the singlet oxygen (1.2) but dependent on DMPO, ?? chrysophanol, oxygen and the irradiation time. The singlet oxygen and OH could also be pro- ? duced by the photosensitization of the photosensitizer. These suggest that chrysophanol pos- sesses the photosensitization activity via Type I mechanism and Type II mechanism. To evaluate the photosensitization activities of MHAQ, emodin and mixed anthraquinone derivatives ex- tracted from rheum, the relative productivities of O2 were estimated to be 1.8, 1.1.and 1.0 re- ?? spectively and the quantum yields for singlet oxygen to be 0.36, 0.53 and 0.1. respectively. Therefore, these low-cost pigments may be potentially used as phototherapeutic medicine for some kind of vascular diseases or photo-activated pesticides.

关键词： chrysophanol, ESR, semiquinone radical anions, superoxide radical anions, hydroxyl radical, singlet oxygen.

High-resolution photofragment translational spectro- scopy for the UV photodissociation of C_2H_5I

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Science China Chemistry 2007年第4期50卷 476-482页

作者： BI WeiBin, XU XiLing, HUANG JianGou, XIAO DaoQing & ZHU QiHe beijing {1. laboratory for molecular Sciences, State Key laboratory of molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, beijing 1.0080, China 1. beijing {1. laboratory for molecular Sciences State Key Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The photodissociation of ethyl iodide at 279.71. 281.73, 304.02 and 304.67 nm has been studied on our new mini-photofragment translational spectrometer with a total flight path of only 5 cm. Some vibra-tional peaks are firstly resolved in the TOF spectra of I*(2P1.2) and I(2P3/2) channels. These vibrational peaks are assigned to the excitation states (ν2 = 0, 1. 2,…) of the umbrella mode (ν2, 540 cm-1. of the photofragment C2H5, and the distribution of the vibrational states is obtained. The dissociation energy has been determined to be D0(C-I)=2.31. ± 0.03 eV. The energy partitioning of the available energy (Eavl=ET+Eint=ET+EV,R) calculated from our experimental data E int /E avl= 22.1. at 281.73 nm, 22.4% at 304.02 nm for the I* channel, and E int /E avl= 25.2% at 279.71.nm, 25.9% at 304.67 nm for the I channel, seem to be more reliable.

关键词： photofragment translational spectroscopy C_2H_5I photodissociation vibrational state distribution energy partitioning dissociation energy

Applications of functionalized ionic liquids

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Science China Chemistry 2006年第5期49卷 385-401页

作者： LI Xuehui1. ZHAO Dongbin2,3, FEI Zhaofu2 & WANG Lefu1.1. Department of Chemical Engineering, Guangdong Provincial laboratory of Green Chemical Technology, South China Uni-versity of Technology, Guangzhou 51.641. China 2. Swiss Federal Institute of Technology, Lausanne, EPFL, CH-1.1. Lausanne, Switzerland 3. PKU Green Chemistry Center, {1. national laboratory for molecular Sciences, College of Chemistry and molecular Engineering, Peking University, {1. 1.0871. China 1. Department of Chemical Engineering Guangdong Provincial Laboratory of Green Chemical Technology South China University of Technology Guangzhou 510641 China 2. Lausanne EPFL Swiss Federal Institute of Technology CH-1015 Lausanne Switzerland 3. PKU Green Chemistry Center Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Recent developments of the synthesis and applications of functionalized ionic liquids (including dual-functionalized ionic liquids) have been highlighted in this review. Ionic liquids are at-tracting attention as alternative solvents in green chemistry, but as more functionalized ILs are pre-pared, a greater number of applications in increasingly diverse fields are found.

关键词： ionic liquids functionalized ionic liquids dual-functionallzed ionicliquids reaction media asymmetric synthesis nano-materials porous materials lubricants flue-gas desulfurization oil desul-furization

Cellulose conversion to polyols on supported Ru catalysts in aqueous basic solution

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Science China Chemistry 2010年第7期53卷 1476-1480页

作者： DENG TianYin,SUN JiYing & LIU HaiChao beijing {1. laboratory for molecular Sciences,State Key laboratory for Structural Chemistry of Stable and Unstable Species Green Chemistry Center,College of Chemistry and molecular Engineering,Peking University,beijing 1.0871.China 1. beijing {1. laboratory for molecular Sciences State Key Laboratory for Structural Chemistry of Stable and Unstable Species Peking University Beijing 100871 China2. Green Chemistry Center College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

It is of great significance and challenge to achieve direct conversion of cellulose to specific polyols,e.g.,ethylene glycol and propylene *** such selective conversion,a novel one-pot approach was studied by combination of alkaline hydrolysis and hydrogenation on supported Ru catalysts.A wide range of bases including solid bases,e.g.,Ca(OH)2 and La2O3,and phosphate buffers were examined in the cellulose reaction in water,and the cellulose conversions and polyol products depended largely on the basicity or pH values in the aqueous *** glycol,1.2-propanediol,and especially 1.2,5-pentanetriol were obtained with selectivities of 1.%,1.% and 22%,respectively,at 38% cellulose conversion at pH 8 in phosphate buffer *** preliminary results provide potentials for efficient conversion of cellulose to targeted polyols by using the advantages of bases.

关键词： cellulose polyols Ru catalysts solid bases aqueous basic solutions

Syntheses, structures and magnetic properties of a family of one-dimensional M(Ⅱ)-lanthanide(Ⅲ) (M = Ni(Ⅱ) and Zn(Ⅱ)) coordination polymers

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Science China Chemistry 2007年第3期50卷 308-317页

作者： ZHANG Wen, ZHAO Fei, LIU Tao & GAO Song beijing {1. laboratory for molecular Sciences, State Key laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and molecular Engineering, Peking University, beijing 1.0871. China 1. beijing {1. laboratory for molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

A series of 1. nickel(II)/zinc(II)-lanthanide(III) coordination polymers, [M(μ-L)2Ln(NO3)3]n·solvents (HL = bis(2-pyridylcarbonyl)amine; M = Ni, Ln = Gd (1.NiGd), Tb (2·NiTb), Dy (3·NiDy), Ho (4·NiHo), Y (5·NiY); M = Zn, Ln = Gd (6·ZnGd), Tb (7·ZnTb), Dy (8·ZnDy), Ho (9·ZnHo); solvents = H2O or H2O-ethanol), was synthesized and characterized. All of the complexes are isostructural at 293 K and crystallize in the orthorhombic space group Fddd. Magnetic measurements were performed on 1.9, where weak ferromagnetic interaction is found in 1.NiGd, ferromagnetic interaction in 2·NiTb and 3·NiDy, and antiferromagnetic interaction in 4·NiHo. A remarkable dc magnetic field dependence of ac susceptibilities was found in this series of complexes.

关键词： nickel lanthanide 3d-4f coordination polymer magnetic property

Influence of magnetic current on the ground state entanglement in an isotropic transverse XY chain

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Progress in Natural Science:Materials International 2007年第10期17卷 1147-1151页

作者： Liu Dan1.2 , Zhang Yong3 and Long Guilu1.2(1. Key laboratory for Atomic and {1. NanoSciences, and Department of Physics, Tsinghua University, beijing 1.0084, China 2. Center of Quantum Information Science and Technology, Tsinghua national laboratory for information Science and Technology, beijing 1.0084, China 3. Institute of Physics, School of Sciences, beijing University of Posts and Telecommunications, beijing 1.0876, China) Key laboratory for Atomic and {1. NanoSciences and Department of Physics Tsinghua University Beijing 100084 China Center of Quantum Information Science and Technology Tsinghua National Laboratory for information Science and Technology Beijing 100084 China Institute of Physics School of Sciences Beijing University of Posts and Telecommunications Beijing 100876 China

We study the ground state entanglement in a three-qubit XY chain under the influence of a magnetization current. It is found that the ground state changes from a W state to a disentangled state as the magnetic field varies. When the Lagrange multiplier λ>3, namely under a strong magnetic current, the ground state holds onto a W state for a large range of the magnetic field strength. A phase transition to the magnetization-current phase occurs under a certain condition.

关键词： Heisenberg-XY chain magnetic-current phase transition.