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101.
Atoms in molecules (AIM) theory is used to determine the properties of functional groups within 73 saturated linear and branched molecules with at most one electronegative atom. The group properties found rigorously in AIM theory and computed in this study are energy, volume, exposed surface area, extent of electron density, charge, dipole moment and polarizability of the group. Properties of atoms and groups within small molecules are presented. Averaged values for group definitions subdivided by their first-bonded neighbors are also presented. Small variability in properties is seen for hydrogen, fluorine, oxygen, nitrogen and larger groups containing the latter three atoms. Greater variability exists within the database of alkyl group values, and the range of these quantities is discussed. Exposed surface area calculations using AIM theory are explained and related to van der Waals (vdW) radii methods. 相似文献
102.
Temperature-programmed desorption (TPD) and reflection absorption infrared spectroscopy (RAIRS) are used to investigate the crystallization kinetics and measure the excess free energy of metastable amorphous solid water films (ASW) of H(2)O and D(2)O grown using molecular beams. The desorption rates from the amorphous and crystalline phases of ASW are distinct, and as such, crystallization manifests can be observed in the TPD spectrum. The crystallization kinetics were studied by varying the TPD heating rate from 0.001 to 3 K/s. A coupled desorption-crystallization kinetic model accurately simulates the desorption spectra and accurately predicts the observed temperature shifts in the crystallization. Isothermal crystallization studies using RAIRS are in agreement with the TPD results. Furthermore, highly sensitive measurements of the desorption rates were used to determine the excess free energy of ASW near 150 K. The excess entropy obtained from these data is consistent with there being a thermodynamic continuity between ASW and supercooled liquid water. 相似文献
103.
In the article [17], we introduced and investigated feebly and flatly projectable frames. In this article, we apply these
two properties to lattice-ordered groups. An example is constructed to illustrate that the two properties are distinct, which
solves a question from [17]. We also investigate these properties with respect to archimedean ℓ-groups with weak order unit,
as well as commutative semiprime f-rings. 相似文献
104.
The observation that dipyridamole inhibits lipoxygenase has been confirmed and extended to soybean lipoxygenase using a luminol endpoint. The ID50 (50% inhibitory concentration) was 3.3 × 10−7 M. Dipyridamole inhibits luminol-dependent Chemiluminescence of human myeloperoxidase (ID50 = 9 × 10−7 M). Dipyridamole inhibits luminol-dependent Chemiluminescence from human neutrophils. 相似文献
105.
Passively mode-locked lasers with intracavity weakly birefringent fiber are theoretically analyzed based on two coupled complex one-dimensional Ginzburg-Landau equations. The model includes fiber birefringence, spectral filtering, saturable gain, and saturable loss. Phase-locked soliton solutions are found for small amounts of birefringence and several types of soliton with periodic polarization evolution for higher amounts of birefringence. Numerical simulations show qualitative agreement with experimental results. 相似文献
106.
New neutral and ionic functionalised zirconocene dichloride compounds have been isolated and characterised. The ionic zirconocene exhibits excellent cytotoxicity against a range of human tumour cell lines, which represents the first active anticancer zirconocene dichloride compound. 相似文献
107.
Neil D. Feasey Nigel J. Forrow Graeme Hogarth Selby A.R. Knox Kirsty A. Macpherson Michael J. Morris A. Guy Orpen 《Journal of organometallic chemistry》1984,267(3):c41-c44
UV irradiation of [Ru2(CO)4(η-C5H5)2] yields the tri- and tetra-ruthenium complexes [Ru2(CO)4(η-C5H5){η-C5H4Ru(CO)2(η-C5H5)}] and [Ru4(CO)6(μ3-C5H4)2(η-C5H5)2]. The μ3-C5H4 ligand in the latter has been characterised through an X-ray diffraction study on [Ru4(CO)5{P(OMe)3}(μ3-C5H4)2(η-C5H5)2]. 相似文献
108.
Summary A new carbon for liquid and gas chromatography, called porous glassy carbon (PGC) is described. The material is made using a porous template filled with carbonizable resin. After firing in an inert atmosphere the template is removed. PGC has been made with surface area ranging from 20 m2/g to 400 m2/g. It is of adequate strength for gas and high-performance liquid chromatography. In gas chromatography it is similar to the commerical graphitized thermal carbon black (GTCB) Carbopack B, but has somewhat less retention per unit surface area and is much more robust. It gives symmetrical peaks for hydrocarbons with k-values up to at least 100. In liquid chromatography it is similar to the GTCB's coated with pyrolytic carbon described by Guiochon. It behaves as a strong reversed phase adsorbent. Fairly good peak symmetry is maintained for k-values up to at least 10 but trace additives to the eluent may be necessary to control peak asymmetry. PGC has considerable potential as a new packing material in both gas and liquid chromatography.Presented at the 14th International Symposium on Chromatography London, September, 1982 相似文献
109.
Kul Ismail Bhat Krishna Knox Alyssa Fischer-Drowos Shirley 《Journal of solution chemistry》2021,50(8):1113-1123
Journal of Solution Chemistry - Measurements of density and speed of sound are reported for phenylboronic acid–water solutions for molalities ranging from 0.0098 to... 相似文献
110.
Dartington Hall-Verwaltung W. J. Knox F. E. Holmes E. Boye A. B. Garrett L. Ju. Kurtz W. G. Woano und B. Jelinek 《Fresenius' Journal of Analytical Chemistry》1943,126(9):337-339
Ohne Zusammenfassung 相似文献