The Experts below are selected from a list of 258 Experts worldwide ranked by ideXlab platform
Hiroshi Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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Effect of a phosphorus atom upon vicinal – coupling constants in pyranose derivatives having a C–P bond: Additivity Rule for the effect of phosphorus substituents
Carbohydrate Research, 1998Co-Authors: Tadashi Hanaya, Hiroshi YamamotoAbstract:Abstract Additivity constants for phosphorus were estimated for the prediction of vicinal 1 H – 1 H coupling constants by means of an Additivity Rule in a series of pyranose analogs having phosphorus as the ring heteroatom. The experimental J values were well reproduced by employing the proposed Additivity constants with a small overall root-mean-square difference of 0.32 Hz. The prediction of coupling constants was employed for the investigation of conformational equilibria of pyranose analogs having a phosphinyl group in the ring or on the ring-carbon.
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effect of a phosphorus atom upon vicinal coupling constants in pyranose derivatives having a c p bond Additivity Rule for the effect of phosphorus substituents
Carbohydrate Research, 1998Co-Authors: Tadashi Hanaya, Hiroshi YamamotoAbstract:Abstract Additivity constants for phosphorus were estimated for the prediction of vicinal 1 H – 1 H coupling constants by means of an Additivity Rule in a series of pyranose analogs having phosphorus as the ring heteroatom. The experimental J values were well reproduced by employing the proposed Additivity constants with a small overall root-mean-square difference of 0.32 Hz. The prediction of coupling constants was employed for the investigation of conformational equilibria of pyranose analogs having a phosphinyl group in the ring or on the ring-carbon.
P M Patel - One of the best experts on this subject based on the ideXlab platform.
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Total electron scattering cross sections for NO, CO, , , and eV)
Journal of Physics B: Atomic Molecular and Optical Physics, 1996Co-Authors: K N Joshipura, P M PatelAbstract:Various total cross sections for electron scattering on the heteronuclear molecules NO, CO, and are calculated at energies from 50 eV onwards. The approximate Additivity Rule used earlier has been modified by separating - molecule interactions into short-range and long-range parts. The resulting modified Additivity Rule for - molecule cross sections is simple but more effective and it yields better accord with experiments, especially above 100 eV incident energy.
Tadashi Hanaya - One of the best experts on this subject based on the ideXlab platform.
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Effect of a phosphorus atom upon vicinal – coupling constants in pyranose derivatives having a C–P bond: Additivity Rule for the effect of phosphorus substituents
Carbohydrate Research, 1998Co-Authors: Tadashi Hanaya, Hiroshi YamamotoAbstract:Abstract Additivity constants for phosphorus were estimated for the prediction of vicinal 1 H – 1 H coupling constants by means of an Additivity Rule in a series of pyranose analogs having phosphorus as the ring heteroatom. The experimental J values were well reproduced by employing the proposed Additivity constants with a small overall root-mean-square difference of 0.32 Hz. The prediction of coupling constants was employed for the investigation of conformational equilibria of pyranose analogs having a phosphinyl group in the ring or on the ring-carbon.
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effect of a phosphorus atom upon vicinal coupling constants in pyranose derivatives having a c p bond Additivity Rule for the effect of phosphorus substituents
Carbohydrate Research, 1998Co-Authors: Tadashi Hanaya, Hiroshi YamamotoAbstract:Abstract Additivity constants for phosphorus were estimated for the prediction of vicinal 1 H – 1 H coupling constants by means of an Additivity Rule in a series of pyranose analogs having phosphorus as the ring heteroatom. The experimental J values were well reproduced by employing the proposed Additivity constants with a small overall root-mean-square difference of 0.32 Hz. The prediction of coupling constants was employed for the investigation of conformational equilibria of pyranose analogs having a phosphinyl group in the ring or on the ring-carbon.
Antonio Zecca - One of the best experts on this subject based on the ideXlab platform.
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Additivity Rule for electron molecule cross section calculation a geometrical approach
Physics Letters A, 1999Co-Authors: Antonio Zecca, Raffaele Melissa, Roberto S Brusa, G P KarwaszAbstract:A new formulation of the Additivity Rule is proposed. Here atomic cross sections are added by taking into account the geometrical screening of the component atoms, as seen by the impinging electron. Atomic cross sections are obtained . starting from the experimental TCS of simple molecules H , N , O , CO via inversion procedure. The model has been 222 successfully applied to the linear molecules NO, N O, CO , for energies as low as 50 eV up to 5 keV. A simplified 22 . algorithm has been used to evaluate the cross sections of NO a bent molecule and of CH : the results underestimate the 24
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Total cross sections for electron scattering on chloromethanes: Formulation of the Additivity Rule
Physical Review A, 1999Co-Authors: Grzegorz P. Karwasz, Roberto S Brusa, Andrea Piazza, Antonio ZeccaAbstract:Total cross sections for electron scattering on CH 3Cl, CH2Cl2 , and CHCl3 have been measured by an absolute method in the ~75‐4000!-eV energy range. The overall experimental error is below 5%. A formulation of the Additivity Rule is proposed. The molecular cross sections are approximated by a Born-like twoparameter formula. We show that the low-energy parameter is correlated to the molecular polarizability. We show also that the high-energy parameter for a given molecule can be expressed as the sum of the high-energy parameters of the constituent atoms. The model has been successfully verified for two groups of halomethanes: the CH4 ,C H 3Cl, CH2Cl2 , CHCl3 , and CCl4 series and the CF4 ,C F 3Cl, CF2Cl2 , CFCl3 , and CCl4 series. The model has been successfully extended to molecules containing Si and S atoms, such as H2S, SF6 , SiH4 , and SiF4 . @S1050-2947~99!10102-1# PACS number~s!: 34.80.Bm, 34.80.Gs Chlorine substituted methanes play an important role in atmospheric chemistry @1#; their time in the Earth’s troposphere is several tens of years. Free Cl radicals formed by ultraviolet-induced dissociation act as catalysts in the chain of reactions leading to the destruction of the stratospheric ozone @2#. In particular, chloromethane (CH3Cl), used in refrigerators and organic chemistry, is the most abundant halocarbon present in the atmosphere. CH3Cl is also the most frequently studied halocarbon in electron-scattering experiments.
K N Joshipura - One of the best experts on this subject based on the ideXlab platform.
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Total electron scattering cross sections for NO, CO, , , and eV)
Journal of Physics B: Atomic Molecular and Optical Physics, 1996Co-Authors: K N Joshipura, P M PatelAbstract:Various total cross sections for electron scattering on the heteronuclear molecules NO, CO, and are calculated at energies from 50 eV onwards. The approximate Additivity Rule used earlier has been modified by separating - molecule interactions into short-range and long-range parts. The resulting modified Additivity Rule for - molecule cross sections is simple but more effective and it yields better accord with experiments, especially above 100 eV incident energy.
