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951.
Oh HB Lin C Hwang HY Zhai H Breuker K Zabrouskov V Carpenter BK McLafferty FW 《Journal of the American Chemical Society》2005,127(11):4076-4083
Previous gas-phase methods for infrared photodissociation spectroscopy (IRPD) require sample volatility. Our method instead uses electrospray ionization to introduce even large nonvolatile molecules into a Fourier transform mass spectrometer, where extended (>15 s) ion storage makes possible high sensitivity spectral measurements with an OPO laser over a range of 3050-3800 cm(-1). The spectra of 22 gaseous proton-bound amino acid complexes are generally correlated with the H-stretching frequencies established for O-H and N-H functional groups in solution. For theoretical structure predictions of the Gly2H+ and N-acylated Asp2H+ dimers, IRPD spectra clearly differentiate between the predicted lowest energy conformers. In contrast to solution, in the gas phase the glycine zwitterion is approximately 20 kcal/mol less stable than the neutral; however, glycine is clearly zwitterionic in the gaseous GlyLysH+ dimer. The level of theory is inadequate for the larger Lys2H+ dimer, as all low energy predicted structures have free carboxyl O-H groups, in contrast to the IR spectrum. IRPD appears to be a promising new technique for providing unique information on a broad range of biomolecular and other gaseous ions, especially on noncovalent bonding involving O-H and N-H groups. 相似文献
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Lv Jia-Liang Zhai Shang-Ru Wang Zhen-Zhen Lei Zhi-Min An Qing-Da 《Research on Chemical Intermediates》2016,42(2):839-854
Research on Chemical Intermediates - There is a growing trend to employ agricultural waste/by-products (AWBs) as substrates for the development of dye bio-sorbents, and surface modification plays a... 相似文献
956.
Fan Yuan Zhai Shangru Liu Na Lv Jialiang Lei Zhimin An Qingda 《Research on Chemical Intermediates》2016,42(2):869-891
Research on Chemical Intermediates - Heavy metal contamination, especially contamination involving Pb(II), is a major environmental problem faced by modern society; hence, research on... 相似文献
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Ji Ran Zhai Shang-Ru Meng Yan-Yun Xiao Zuo-Yi An Qing-Da 《Journal of Sol-Gel Science and Technology》2017,84(1):180-191
Journal of Sol-Gel Science and Technology - Palladium-based catalysts with equably distributions of surface functionalities are synthesized by anchoring palladium nanoparticles onto N-doped carbon... 相似文献
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Back Cover: Total Synthesis,Stereochemical Assignment,and Field‐Testing of the Sex Pheromone of the Strepsipteran Xenos peckii (Chem. Eur. J. 18/2016) 下载免费PDF全文
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Dr. Huijie Qiao Dr. Liting Yang Xiubei Yang Jialin Wang Ya Chen Dr. Lin Zhang Wuxuan Sun Dr. Lipeng Zhai Prof. Liwei Mi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(26):e202200600
Two new covalent organic frameworks (COFs) were synthesized from 4,4′,4′′,4′′′-(pyrene-1,3,6,8-tetrayl)tetraaniline and 2,5-dimethoxyterephthalaldehyde (Py-DMTA-COF) or 2′,5′-dimethoxy-[1,1′:4′,1′′-terphenyl]-4,4′′-dicarbaldehyde (Py-DMTPDA-COF) under solvothermal conditions. These two COFs were further facilely developed as efficient photocatalytic platforms for the synthesis of thiophosphinates. Py-DMTA-COF exhibited better photocatalytic activity, broad substrate applicability, and excellent recycling capacity for the preparation of thiophosphinates from P(O)H compounds and thiols compared to Py-DMTPDA-COF. This methodology was further extended to the seamless gram-scale production of target phosphorothioate derivatives. The results demonstrate that COFs can provide a robust platform for developing metal-free, base-free, highly efficient, and reusable heterogeneous photocatalysts for organic transformations. 相似文献