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11.
Al-Rafia SM Malcolm AC McDonald R Ferguson MJ Rivard E 《Angewandte Chemie (International ed. in English)》2011,50(36):8354-8357
Putting on some weight: A series of stable adducts featuring the hitherto unknown mixed heavy ethylene analogues H(2) SiGeH(2) and H(2) SiSnH(2) were prepared using a versatile donor-acceptor method. 相似文献
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Al-Rafia SM Malcolm AC Liew SK Ferguson MJ Rivard E 《Journal of the American Chemical Society》2011,133(4):777-779
The heavy group 14 methylene analogues, EH2, (E = Ge and Sn) have been stabilized via efficient methods, thus enabling the chemistry of these novel inorganic hydrides to be explored in depth. 相似文献
13.
AM Cardoso SM Alexandre CM Barros AJ Correia NM Nibbering 《Rapid communications in mass spectrometry : RCM》1999,13(19):1885-1888
The collision-induced dissociation (CID) of deprotonated arylalkylamines of general formula R(1)C(6)H(4)CHR(2)CH(2)NR(3)(2) (where R(1) = H, OH, F or NO(2); R(2) = H or OH; R(3) = H or CH(3)) generated by negative chemical ionization with H(2)O and D(2)O as ionizing reagents, is discussed. The negative chemical ionization mass spectra show that, in the absence of a hydroxy group in the aromatic ring, deprotonation takes place at the benzylic position whereas the proton is lost from the OH group when present. The nitro compound forms only M(-.) ions. The CID spectra of the deprotonated molecules show that fragmentations are strongly dependent on the structural features of the molecules, namely the presence or absence of substituents in the aromatic ring or aliphatic chain. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
14.
Liew SK Al-Rafia SM Goettel JT Lummis PA McDonald SM Miedema LJ Ferguson MJ McDonald R Rivard E 《Inorganic chemistry》2012,51(9):5471-5480
The synthesis and coordination chemistry of a series of dianionic bis(amido)silyl and bis(amido)disilyl, [NSiN] and [NSiSiN], chelates with N-bound aryl or sterically modified triarylsilyl (SiAr(3)) groups is reported. In order to provide a consistent comparison of the steric coverage afforded by each ligand construct, various two-coordinate N-heterocyclic germylene complexes featuring each ligand set were prepared and oxidative S-atom transfer chemistry was explored. In the cases where clean oxidation transpired, sulfido-bridged centrosymmetric germanium(IV) dimers of the general form [LGe(μ-S)](2) (L = bis(amidosilyl) ligands) were obtained in lieu of the target monomeric germanethiones with discrete Ge═S double bonds. These results indicate that the reported chelates possess sufficient conformational flexibility to allow for the dimerization of LGe═S units to occur. Notably, the new triarylsilyl groups (4-RC(6)H(4))(3)Si- (R = (t)Bu and (i)Pr) still offer considerably expanded degrees of steric coverage relative to the parent congener, -SiPh(3,) and thus the use of substituted triarylsilyl groups within ligand design strategies should be a generally useful concept in advancing low-coordination main group and transition-metal chemistry. 相似文献
15.
Al-Rafia SM Malcolm AC Liew SK Ferguson MJ McDonald R Rivard E 《Chemical communications (Cambridge, England)》2011,47(24):6987-6989
The N-heterocyclic olefin, IPr=CH(2) (IPr = [(HCNDipp)(2)C], Dipp = 2,6-(i)Pr(2)C(6)H(3)) has been demonstrated to be of sufficient Lewis basicity to stabilize main group hydrides in unusually low oxidation states. 相似文献
16.
This paper outlines the benefits of computational steering for high performance computing applications. Lattice-Boltzmann mesoscale fluid simulations of binary and ternary amphiphilic fluids in two and three dimensions are used to illustrate the substantial improvements which computational steering offers in terms of resource efficiency and time to discover new physics. We discuss details of our current steering implementations and describe their future outlook with the advent of computational grids. 相似文献
17.
空气中激光烧蚀Cu产生等离子体发射光谱的研究 总被引:6,自引:3,他引:3
利用Q-开关Nd:YAG激光器产生的1.06 μm、10 ns的脉冲激光聚焦在空气中的Cu靶上,观测了激光诱导的Cu等离子体发射光谱.采用不同的激光能量,分析了波长范围为440 nm到540 nm的空间分辨发射光谱.在局部热力学平衡(LTE)条件近似下,根据谱线的相对强度,得到了等离子体电子温度约在104 K以上,给出了靶面附近电子温度的空间演化规律,并探讨了N(Ⅱ)500.52 nm谱线的谱线强度和半高全宽随激光能量的变化规律. 相似文献
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19.
Maximizing nonlinear light-matter interactions is a primary motive for compressing laser pulses to achieve ultrashort transform limited pulses. Here we show how, by appropriately shaping the pulses, resonant multiphoton transitions can be enhanced significantly beyond the level achieved by maximizing the pulse's peak intensity. We demonstrate the counterintuitive nature of this effect with an experiment in a resonant two-photon absorption, in which, by selectively removing certain spectral bands, the peak intensity of the pulse is reduced by a factor of 40, yet the absorption rate is doubled. Furthermore, by suitably designing the spectral phase of the pulse, we increase the absorption rate by a factor of 7. 相似文献
20.
Al-Rafia SM Malcolm AC McDonald R Ferguson MJ Rivard E 《Chemical communications (Cambridge, England)》2012,48(9):1308-1310
A stable Si(II) dihydride complex, IPr·SiH(2)·BH(3) (IPr = [(HCNDipp)(2)C:]; Dipp = 2,6-(i)Pr(2)C(6)H(3)), was synthesized and preliminary reactivity involving this source of encapsulated silylene is reported. 相似文献