When A E ∈LR（H） and B E ∈LR（K） are given, for C E∈LR（K, H） we denoteby Mc the linear relation acting on the infinite dimensional separable Hilbert space H Kof the formIn this paper, we give the necessary and ...When A E ∈LR（H） and B E ∈LR（K） are given, for C E∈LR（K, H） we denoteby Mc the linear relation acting on the infinite dimensional separable Hilbert space H Kof the formIn this paper, we give the necessary and sufficient conditionson A and B for wh{ch Mc is upper semi-Fredholm with negative index or Weyl for some C C ∈LR（K, H）.展开更多
According to the appearing of isosbestic point in the absorption spectra of Ho/Y-Tribromoarsenazo (TBA)systems,the complexation reaction is considered to be M+nL=ML_n.A method has been proposed based on it for calcula...According to the appearing of isosbestic point in the absorption spectra of Ho/Y-Tribromoarsenazo (TBA)systems,the complexation reaction is considered to be M+nL=ML_n.A method has been proposed based on it for calculating the mole fraction of free complexing agent in the solutions from spectral data.and two linear regression formula have been introduced to determine the composition,the molar absorptivity,the conditional stability constant of the complex and the concentration of the complexing agent. This method has been used in Ho-TBA and Y-TBA systems.Ho^(3+)and Y^(3+)react with TBA and form 1: 2 complexes in HCl-NaAc buffer solution at pH 3.80.Their molar absorptivities determined are 1.03×10~8 and 1.10×10~8 cm^2·mol^(-1),and the conditional stability constants(logβ_2)are 11.37 and 11.15 respectively.After considering the pH effect in TBA complexing,their stability constants(log β_2^(ahs))are 43.23 and 43.01. respectively.The new method is adaptable to such systems where the accurate concentration of the complexing agent can not be known conveniently.展开更多
Reinvestigation of the growth of L-proline succinate (1) (Paramasivam and Ramachandra Raja, Journal of Crystallization Process and Technology, 2 (2012) 21 - 24;Balamurugaraj et al., Journal of Material Physics and Che...Reinvestigation of the growth of L-proline succinate (1) (Paramasivam and Ramachandra Raja, Journal of Crystallization Process and Technology, 2 (2012) 21 - 24;Balamurugaraj et al., Journal of Material Physics and Chemistry 1 (2013) 4 - 8) and L-threonine zinc acetate (2) (Puhal Raj and Ramachandra Raja, Photonics and Optoelectronics, 2 (2013) 56 - 64) is reported. Slow evaporation of an aqueous solution containing equimolar quantities of L-proline and succinic acid (for 1) and L-threonine and zinc acetate (for 2) results in the fractional crystallization of succinic acid (in the first case) and L-threonine (in the second case) and not any novel organic non-linear optical (NLO) crystals. In this paper, the usefulness of infrared spectra for correct product characterization is demonstrated.展开更多
In the present study, structural properties of 4,4’ dimethylaminocyanobiphenyl (DMACB) have been studied extensively by using ab initio Hartree Fock (HF) and density functional theory (DFT) employing B3LYP/B3PW91 exc...In the present study, structural properties of 4,4’ dimethylaminocyanobiphenyl (DMACB) have been studied extensively by using ab initio Hartree Fock (HF) and density functional theory (DFT) employing B3LYP/B3PW91 exchange correlation levels of theory. The vibrational frequencies of DMACB in the ground state have been calculated by using Hartree Fock level and density functional method (B3LYP/B3PW91) with 6-31G(d, p), basis set. Nonlinear optical (NLO) behavior of the examined molecule is investigated by the determination of the electric dipole moment μ, the polarizability α, and the hyperpolarizability β by using the B3LYP/B3PW91 methods.展开更多
The utilization of the Raman spectra of the low frequency bending mode for three quasi-linear molecules: disiloxane,(SiH3)2O;methylisocyanate,CH3NCO;and dimethylisocyanate,(CH3)2SiHNCO for observing the low frequency ...The utilization of the Raman spectra of the low frequency bending mode for three quasi-linear molecules: disiloxane,(SiH3)2O;methylisocyanate,CH3NCO;and dimethylisocyanate,(CH3)2SiHNCO for observing the low frequency anharmonic bending vibration is demonstrated which is superior to the corresponding far infrared spectra.From the observed frequencies from the Raman spectra the potential function governing the heavy atom motion to linearity has been obtained from which the barrier has been determined.These experimental values are compared to the ab initio predicted values.Also low frequency Raman spectra of the ring puckering vibration of chlorocyclobutane,c-C4H7Cl,bromocyclobutane,c-C4H7Br,and aminocyclobutane,c-C4H7NH2,have been utilized to obtain the potential function governing the ring inversion for these molecules.The determined barriers to planarity are compared to those obtained from MP2(full) ab initio and density functional theory B3LYP calculations by utilizing a variety of basis sets.For all of these studies it is shown that the Raman spectra are superior to the infrared spectra for determining the frequencies of the excited state transitions.展开更多
基金the National Natural Science Foundation of China，the National Basic Research Program，the Strategic Priority Research Program of Chinese Academy of Sciences
文摘When A E ∈LR（H） and B E ∈LR（K） are given, for C E∈LR（K, H） we denoteby Mc the linear relation acting on the infinite dimensional separable Hilbert space H Kof the formIn this paper, we give the necessary and sufficient conditionson A and B for wh{ch Mc is upper semi-Fredholm with negative index or Weyl for some C C ∈LR（K, H）.
文摘According to the appearing of isosbestic point in the absorption spectra of Ho/Y-Tribromoarsenazo (TBA)systems,the complexation reaction is considered to be M+nL=ML_n.A method has been proposed based on it for calculating the mole fraction of free complexing agent in the solutions from spectral data.and two linear regression formula have been introduced to determine the composition,the molar absorptivity,the conditional stability constant of the complex and the concentration of the complexing agent. This method has been used in Ho-TBA and Y-TBA systems.Ho^(3+)and Y^(3+)react with TBA and form 1: 2 complexes in HCl-NaAc buffer solution at pH 3.80.Their molar absorptivities determined are 1.03×10~8 and 1.10×10~8 cm^2·mol^(-1),and the conditional stability constants(logβ_2)are 11.37 and 11.15 respectively.After considering the pH effect in TBA complexing,their stability constants(log β_2^(ahs))are 43.23 and 43.01. respectively.The new method is adaptable to such systems where the accurate concentration of the complexing agent can not be known conveniently.
文摘Reinvestigation of the growth of L-proline succinate (1) (Paramasivam and Ramachandra Raja, Journal of Crystallization Process and Technology, 2 (2012) 21 - 24;Balamurugaraj et al., Journal of Material Physics and Chemistry 1 (2013) 4 - 8) and L-threonine zinc acetate (2) (Puhal Raj and Ramachandra Raja, Photonics and Optoelectronics, 2 (2013) 56 - 64) is reported. Slow evaporation of an aqueous solution containing equimolar quantities of L-proline and succinic acid (for 1) and L-threonine and zinc acetate (for 2) results in the fractional crystallization of succinic acid (in the first case) and L-threonine (in the second case) and not any novel organic non-linear optical (NLO) crystals. In this paper, the usefulness of infrared spectra for correct product characterization is demonstrated.
文摘In the present study, structural properties of 4,4’ dimethylaminocyanobiphenyl (DMACB) have been studied extensively by using ab initio Hartree Fock (HF) and density functional theory (DFT) employing B3LYP/B3PW91 exchange correlation levels of theory. The vibrational frequencies of DMACB in the ground state have been calculated by using Hartree Fock level and density functional method (B3LYP/B3PW91) with 6-31G(d, p), basis set. Nonlinear optical (NLO) behavior of the examined molecule is investigated by the determination of the electric dipole moment μ, the polarizability α, and the hyperpolarizability β by using the B3LYP/B3PW91 methods.
文摘The utilization of the Raman spectra of the low frequency bending mode for three quasi-linear molecules: disiloxane,(SiH3)2O;methylisocyanate,CH3NCO;and dimethylisocyanate,(CH3)2SiHNCO for observing the low frequency anharmonic bending vibration is demonstrated which is superior to the corresponding far infrared spectra.From the observed frequencies from the Raman spectra the potential function governing the heavy atom motion to linearity has been obtained from which the barrier has been determined.These experimental values are compared to the ab initio predicted values.Also low frequency Raman spectra of the ring puckering vibration of chlorocyclobutane,c-C4H7Cl,bromocyclobutane,c-C4H7Br,and aminocyclobutane,c-C4H7NH2,have been utilized to obtain the potential function governing the ring inversion for these molecules.The determined barriers to planarity are compared to those obtained from MP2(full) ab initio and density functional theory B3LYP calculations by utilizing a variety of basis sets.For all of these studies it is shown that the Raman spectra are superior to the infrared spectra for determining the frequencies of the excited state transitions.
