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141.
142.
Dr. Xinxing Zhang Gaoxiang Liu Prof. Dr. Karl‐Heinz Meiwes‐Broer Prof. Dr. Gerd Ganteför Prof. Dr. Kit Bowen 《Angewandte Chemie (International ed. in English)》2016,55(33):9644-9647
Gas phase reactions between PtHn? cluster anions and CO2 were investigated by mass spectrometry, anion photoelectron spectroscopy, and computations. Two major products, PtCO2H? and PtCO2H3?, were observed. The atomic connectivity in PtCO2H? can be depicted as HPtCO2?, where the platinum atom is bonded to a bent CO2 moiety on one side and a hydrogen atom on the other. The atomic connectivity of PtCO2H3? can be described as H2Pt(HCO2)?, where the platinum atom is bound to a formate moiety on one side and two hydrogen atoms on the other. Computational studies of the reaction pathway revealed that the hydrogenation of CO2 by PtH3? is highly energetically favorable. 相似文献
143.
Grubisic A Li X Stokes ST Cordes J Ganteför GF Bowen KH Kiran B Jena P Burgert R Schnöckel H 《Journal of the American Chemical Society》2007,129(18):5969-5975
Anion photoelectron spectroscopy and density functional theory were employed to study aluminum hydride clusters, AlnHm- (4 相似文献
144.
RD Harris WS Baker Van Stipdonk MJ RM Crooks EA Schweikert 《Rapid communications in mass spectrometry : RCM》1999,13(14):1374-1380
A suite of keV polyatomic or 'cluster' projectiles was used to bombard unoxidized and oxidized self-assembled monolayer surfaces. Negative secondary ion yields, collected at the limit of single ion impacts, were measured and compared for both molecular and fragment ions. In contrast to targets that are orders of magnitude thicker than the penetration range of the primary ions, secondary ion yields from polyatomic projectile impacts on self-assembled monolayers show little to no enhancement when compared with monatomic projectiles at the same velocity. This unusual trend is most likely due to the structural arrangement and bonding characteristics of the monolayer molecules with the Au(111). Copyright 1999 John Wiley & Sons, Ltd. 相似文献
145.
H. Kazemi S. T. G. Wootton N. J. Cronin S. R. Davies R. E. Miles R. D. Pollard J. M. Chamberlain D. P. Steenson J. W. Bowen 《International Journal of Infrared and Millimeter Waves》1999,20(5):967-974
Schottky barrier diodes have been integrated into on-chip rectangular waveguides. Two novel techniques have been developed to fabricate diodes with posts suitable for integration into waveguides. One technique produces diodes with anode diameters of the order of microns with post heights from 90 to 125 microns and the second technique produces sub-micron anodes with post heights around 20 microns. A method has been developed to incorporate these structures into a rectangular waveguide and provide a top contact onto the anode which could be used as an I.F. output in a mixer circuit. Devices have been fabricated and D.C. characterized. 相似文献
146.
用超对称性和形不变性方法求解环形振子的能谱和波函数 总被引:1,自引:0,他引:1
运用超对称性和形不变性方法计算环形振子的能量本征值和本征波函数.所得到的能谱公式与用费曼路径积分方法得到的严格解完全一致. 相似文献
147.
Bowen Chen Facai Wei Zhiheng Ma Yonghui Peng Haitao Guo Yuexi Wang Shaojian Guan Jianwei Fu Chengbin Jing Jiangong Cheng Jiaqiang Xu Shaohua Liu 《Journal of polymer science. Part A, Polymer chemistry》2024,62(8):1588-1596
Mesoporous polymer nanofilms combine the advantages of the unique structure of mesopores, the quasi-2D configuration of the films, and the inherent properties of polymers, and have become a kind of ideal candidate for the high-performance micro-nano devices due to their highly accessible surface area and exposed active sites. However, the facile preparation of polymer nanofilms with well-defined mesostructures has remained a great challenge due to the lack of synthetic strategies. In this study, we developed a simple soft-template interfacial co-assembly strategy to in-situ construct mesoporous polydopamine nanofilms with uniform thickness (30 nm) and regularly distributed mesopore arrays (average pore size of 12 nm) on surfaces with different types and morphologies. Furthermore, a single-layer mesoporous polymer nanofilm was directly grown on a quartz crystal microbalance substrate and its performance for sensing formaldehyde was studied. The resulted sensor showed excellent sensing response, fast response/recovery dynamics, and great stability, presenting a great promising landscape for trace detection of formaldehyde gas. 相似文献
148.
Guyan Liang Xiannong Chen J. A. Dustman Anita H. Lewin J. Phillip Bowen 《Journal of computational chemistry》1997,18(11):1371-1391
The geometries and vibrational frequencies of 11 training molecules containing the ammonium ion moiety were calculated at the MP2/6-31+G* level of theory. Various torsional energy profiles were also calculated using this basis set. From those ab initio calculations, a molecular mechanics (MM3) force field was developed using our Parameter Analysis and Refinement Toolkit System (PARTS). Using this set of parameters, the MM3 force field was found to well reproduce the molecular geometries and vibrational spectra for the all training molecules. CPU time was reduced from days to seconds. The availability of this new force field dramatically increases the feasibility of the computer-assisted drug design involving ammonium and protonated amino groups. © 1997 by John Wiley & Sons, Inc. J Comput Chem 18 : 1371–1391, 1997 相似文献
149.
FENG Jing WANG Yuting ZOU Linyi LI Bowen HE Xiaofeng LIU Shengna CHEN Tingting FAN Zhuangjun REN Yueming L Yanzhuo 《高等学校化学研究》2015,31(3):439-442
ZnFe2O4(ZFO) was synthesized via a sol-gel method firstly, then the ZFO was irradiated with microwave treatment to obtain M-ZFO using NH4Cl as dispersant for 10 min to improve the photocatalytic activity. Large particles of ZFO were broken into small and uniform particles by the gases of hydrogen chlorine and ammonia during the decomposition of NH4Cl. Compared to ZnFe2O4 without microwave treatment(ZFO), M-ZFO exhibits smaller particle size, higher surface area and larger saturation magnetization. More importantly, the photocatalytic activity of M-ZFO for methylene blue was increased by 25% compared with that of ZFO. 相似文献
150.
Haifeng Zeng Sean Bowen Christian Hilty 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2009,199(2):159-165
A scheme capable of acquiring heteronuclear 2D NMR spectra of hyperpolarized sample is described. Hyperpolarization, the preparation of nuclear spins in a polarized state far from thermal equilibrium, can increase the NMR signal by several orders of magnitude. It presents opportunities to apply NMR spectroscopy to dilute samples that would otherwise yield insufficient signal. However, conventional 2D NMR spectroscopy, which is commonly applied for the determination of molecular structure, relies on the recovery of the initial polarization after each transient. For this reason, it cannot be applied directly to a sample that has been hyperpolarized once. With appropriately modified pulse schemes, two-dimensional NMR spectra an however be acquired sequentially by utilizing a small portion of the hyperpolarized signal in every scan, while keeping the remaining polarization for future scans. We present heteronuclear multi-quantum spectra of single hyperpolarized samples using this technique, and discuss different options for distributing the polarization among different scans. This robust method takes full advantage of Fourier NMR to resolve overlapping chemical shifts, and may prove particularly useful for the structural elucidation of compounds in mass-limited samples. 相似文献