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21.
The interacting boson approximation IBA-1 model space, in which neutron and proton degrees of freedom are not distinguished, can be considered as a subspace of the IBA-2 model space. Using the microscopic background of the IBA-2 model, a correspondence can be established between IBA-1 and IBA-2 model space. Since the space of the IBA-1 model can be regarded as a subspace of the IBA-2 model there is a unique way to ‘Project’ the operators of the IBA-2 model onto those of IBA-1. This projection can be carried out using theF-spin formalism. In the IBA-2 model, the lowest states are indeed fully symmetric, and using the calculations with the help of this projection, we explore the energy levels and the electric quadrupole transition probabilitiesB(E2; {ie393-01}) and γ-ray E2/M1 mixing ratios for selected transitions of162, 164, 166, 168, 170Er. Owing to admixtures of non-fully-symmetric states in IBA-2, we renormalized the parameters (ε) and (κ). This is the first time we show that this projection can be applied to some heavier isotopes and the results obtained for162, 164, 166, 168, 170Er isotopes are reasonably in good agreement with the previous experimental values.  相似文献   
22.
Trillium govanianum Wall. ex D. Don (Melanthiaceae alt. Trilliaceae), commonly known as ‘nagchhatry’ or ‘teen patra’, distributed from Pakistan to Bhutan about 2500–3800 m altitude is indigenous to Himalayas region. In folk medicine the plant has been reported for the treatment of wound healing, sepsis and in various sexual disorders. This paper reports, for the first time, to evaluate the cytotoxicity, in vitro anti-leishmanial (promastigotes) and fingerprint HPLC-photodiode array analysis of the MeOH extract of the roots of T. govanianum and its solid phase extraction fractions. Reverse phase HPLC-PDA based quantification revealed the presence of significant amount of quercetin, myrecetin and kaemferol ranging from 0.221to 0.528 μg/mg DW. MeOH extract revealed distinguishable protein kinase inhibitory activity against Streptomyces 85E strain with 18 mm bald phenotype. The remarkable toxicity profile against brine shrimps and leishmanial was manifested by MeOH extract with LC50 10 and 38.5 μg/mL, respectively.  相似文献   
23.
Thermogravimetric analyses of diclofenac sodium, its Ca2+ and Fe3+ complexes manifested a decreasing trend of the onset decomposition temperatures at which these compounds dissociated. The drop in the temperature was metal ion dependent; the sodium salt showed thermal stability up to 245 °C, whereas the complexes started their degradation processes at temperatures starting from 90 °C. While G* for the cleavage of the acetate moiety in the sodium salt was 63.76 kJmol−1, it was 82.06 and 140.57 kJmol−1 in the cases of Ca2+ and Fe3+, respectively. However, their complete fusion took place at 187.65, 150.34 and 98.77 °C, respectively, displaying a reversed trend which is probably indicative of some catalytic part on the binding metals.

Using the Gaussian 98 W package of programs, ab initio molecular orbital treatments were applied to diclofenac and its Ca2+ and Fe3+ metal complexes to study their electronic structure at the atomic level. The thermochemistry of diclofenac sodium was followed through the TG fragmentation peak temperatures using the density functional theory calculations at the 6-31G(d) basis set level. The FT-IR data were in good agreement with the theoretically calculated values.

Single point calculations at the B3LYP/ 6-311G(d) level of theory, were used to compare the geometric features, energies and dipole moments of these compounds to detect the effect of the binding metal ions on the thermal dissociation of their diclofenac complexes.  相似文献   

24.
Iridoid glycosides from Globularia davisiana   总被引:1,自引:0,他引:1  
From the ethanolic extract of the aerial parts of Globularia davisiana, a new iridoid glycoside, davisioside (1), was isolated. Davisioside (1) comprises a rare iridoid aglycone structure with a saturated double bond between C-3 and C-4. Nine known iridoid glycosides, asperuloside (2), alpinoside (3), geniposide (4), globularin (5), globularicisin (6), 10-O-benzoylcatalpol (7), lytanthosalin (8), melampyroside (9), agnuside (10), and three known phenylethanoid glycosides, verbascoside, isoacteoside and leucosceptoside A were also isolated and characterized. The structures of the isolates were established by spectroscopic methods (one-dimensional (1D)- and two-dimensional (2D)-NMR, MS).  相似文献   
25.
Two new lucidin type anthraquinone glycosides, putorinoside A (1) and putorinoside B (2) were isolated from Putoria calabrica, in addition to two known anthraquinone glycosides, lucidin 3-O-beta-glucopyranoside (3) and lucidin 3-O-primeveroside (4). Based on spectroscopic data, putorinosides A and B were identified as 2-hydroxymethyl-1-methoxy-3,5,6-trihydroxyanthraquinone 3-O-beta-glucopyranoside and 2-hydroxymethyl-1-methoxy-3,6-dihydroxyanthraquinone 3-O-beta-glucopyranoside, respectively.  相似文献   
26.
A series of trimethyltin diorganothiophosphinates Me3SnOSPR′R″ (R′R″ = Me2, MePh, Ph2) was prepared from (Me3Sn)2O and R′R″PSCl in cyclohexane solution. A close study of the vibrational spectra is given; 31P NMR and mass spectra are also reported. The structural investigation of Me3SnOSPMe2 by means of X-ray diffraction (R 5.2%, 1697 observed independent reflexions) shows the compound to consists of chains, in which planar SnMe3 units and tetrahedral OSPMe2 groups are linked by the O- and S-atoms of the thiophosphinate.  相似文献   
27.
In addition to rare phenylethanoid triglycosides, myricoside and its dimetylether derivative serratumoside A {3-hydroxy,4-methoxy-beta-phenylethoxy-O-beta-D-apiofuranosyl-(1-->3)-alpha-L-rhamnopyranosyl-(1-->3)-4-O-feruloyl-beta-D-glucopyranoside}, a new phenylethanoid glycoside, myricoside-3"-O-methylether {3,4-dihydroxy-beta-phenylethoxy-O-beta-D-apiofuranosyl-(1-->3)-alpha-L-rhamnopyranosyl-(1-->3)-4-O-feruloyl-beta-D-glucopyranoside} along with a new neolignan glucoside, (7S, 8R)-dehydroconiferyl alcohol-8-5'-dehydroconiferyl aldehyde 4-O-beta-D-glucopyranoside were isolated from the aerial parts of Phlomis oppositiflora. The structures of the new compounds were identified by means of spectroscopic (UV, IR, 1D- and 2D-NMR, and LC-ESIMS) methods.  相似文献   
28.
29.
Research on Chemical Intermediates - Investigating transition metal oxidants is a fundamental scientific interest for the synthesis of polymer nanocomposites. In this study, we attempted for the...  相似文献   
30.
Applied Biochemistry and Biotechnology - The original version of this article unfortunately contained a mistake in the image of Figure 1 and in Table 4. The corrected version of the figure...  相似文献   
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