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21.
Several amino acid ester hydrochlorides were reacted with ammonium formate to give N-formyl amino acid esters in good yields. 相似文献
22.
A comparative investigation was carried out on the suitability of atomic absorption spectrometry and of emission spectrography with arc and hollow-cathode excitation sources for determination of gallium (μg g-1) in biological samples. The three methods give reliable results. Hollow-cathode emission spectrography was found to be influenced to a lesser extent by matrix effects and to be more precise than the other two techniques. 相似文献
23.
Frabetti PL Cheung HW Cumalat JP Dallapiccola C Ginkel JF Greene SV Johns WE Nehring MS Butler JN Cihangir S Gaines I Garbincius PH Garren L Gourlay SA Harding DJ Kasper P Kreymer A Lebrun P Shukla S Bianco S Fabbri FL Sarwar S Zallo A Culbertson R Gardner RW Greene R Wiss J Alimonti G Bellini G Caccianiga B Cinquini L Di Corato M Giammarchi M Inzani P Leveraro F Malvezzi S Menasce D Meroni E Moroni L Pedrini D Perasso L Sala A Sala S Torretta D Vittone M Buchholz D Claes D Gobbi B O'Reilly B 《Physical review letters》1993,71(6):827-830
24.
Frabetti PL Cheung HW Cumalat JP Dallapiccola C Ginkel JF Greene SV Johns WE Nehring MS Butler JN Cihangir S Gaines I Garren L Garbincius PH Gourlay SA Harding DJ Kasper P Kreymer A Lebrun P Shukla S Bianco S Fabbri FL Sarwar S Zallo A Culbertson R Gardner RW Greene R Wiss J Alimonti G Bellini G Caccianiga B Cinquini L Di Corato M Giammarchi M Inzani P Leveraro F Malvezzi S Menasce D Meroni E Moroni L Pedrini D Perasso L Sala A Sala S Torreta D Vittone M Buchholz D Claes D Gobbi B O'Reilly B 《Physical review letters》1993,70(14):2058-2061
25.
Frabetti PL Cheung HW Cumalat JP Dallapiccola C Ginkel JF Greene SV Johns WE Nehring MS Butler JN Cihangir S Gaines I Garren L Garbincius PH Gourlay SA Harding DJ Kasper P Kreymer A Lebrun P Shukla S Bianco S Fabbri FL Sarwar S Zallo A Culbertson R Gardner RW Greene R Wiss J Alimonti G Bellini G Caccianiga B Cinquini L Di Corato M Giammarchi M Inzani P Leveraro F Malvezzi S Menasce D Meroni E Moroni L Pedrini D Perasso L Sala A Sala S Torretta D Vittone M Buchholz D Claes D Gobbi B O'Reilly B 《Physical review letters》1993,70(10):1381-1384
26.
Frabetti PL Cheung HW Cumalat JP Dallapiccola C Ginkel JF Greene SV Johns WE Nehring MS Butler JN Cihangir S Gaines I Garren L Garbincius PH Gourlay SA Harding DJ Kasper P Kreymer A Lebrun P Shukla S Bianco S Fabbri FL Sarwar S Zallo A Culbertson R Gardner RW Greene R Wiss J Alimonti G Bellini G Caccianiga B Cinquini L Di Corato M Giammarchi M Inzani P Leveraro F Malvezzi S Menasce D Meroni E Moroni L Pedrini D Perasso L Sala A Sala S Toretta D Vittone M Buchholz D Claes D Gobbi B O'Reilly B 《Physical review letters》1993,70(12):1755-1758
27.
Patel RN Singh N Shukla KK Gundla VL Chauhan UK 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(11-12):2603-2610
X-band electron spin resonance (ESR) and UV-vis spectra of a homobinuclear [(Bipy)2Cu-E-Im-Cu(Bipy)2](BF4)3 and a heterobinuclear [(Bipy)2Cu-E-Im-Zn(Bipy)2](BF4)3 complexes, E-Im=2-ethylimidazolate ion have been described as possible models for superoxide dismutase (SOD). Magnetic moment and ESR spectral measurements of the homobinuclear complex have shown an antiferromagnetic exchange interaction. From pH-dependent ESR and UV-vis spectral measurements studies, these complexes have been found to be stable over 8.5-10.5 pH range. These complexes catalyze the dismutation of superoxide (O2-) at biological pH. All the observations indicate that these complexes act as good possible models for superoxide dismutase. 相似文献
28.
Priti Hansia Saraswathi Vishveshwara Samir Kumar Pal 《Chemical physics letters》2006,420(4-6):512-517
Femtosecond spectroscopy carried out earlier on Monellin and some other systems has given insights into the hydration dynamics of the proteins. In the present work, molecular dynamics simulations have been performed on Monellin to study the hydration dynamics. A method has been described to follow up the molecular events of the protein–water interactions in detail. The time constants of the survival correlation function match well with the reported experimental values. This validates the procedure, adapted here for Monellin, to investigate the hydration dynamics in general. 相似文献
29.
Frequency-dependent multipole polarizabilities of the He sequence have been calculated from a hydrodynamic model of quantum mechanics and using an independent-particle model Hamiltonian. Our present scheme is parallel to the uncoupled Hartree–Fock approximation so our values of polarizabilities, multipole transition energies and dispersion force coefficients between the He? He pair are comparable with earlier works using the uncoupled Hartree–Fock approximation. 相似文献
30.
J. P. Shukla V. K. Manchanda M. S. Subramanian 《Journal of Radioanalytical and Nuclear Chemistry》1976,29(1):61-68
A rapid method for the synergistic extraction and spectrophotometric determination of plutonium(VI) in milligram amounts using
a mixture of thenoyltrifluoroacetone (TTA) and tributyl phosphate (TBP) in benzene has been developed. Quantitative extraction
is obtained from aqueous solutions of pH=2 affording separation from many commonly occurring impurities, viz., thorium, fission
products and cladding materials. The precision and accuracy of the method has been found to be∼1%. The study of the solid
product isolated from the extraction system indicates the stoichiometry of the extracted species as PuO2(TTA)2 TBP. 相似文献