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51.
52.
Mansoor Ahmed Qazi Ümmühan Ocak Miraç Ocak Shahabuddin Memon Imam Bakhsh Solangi 《Journal of fluorescence》2013,23(3):575-590
A readily available chromionophore 5,11,17,23-tetra-tert-butyl-25,27-bis(hydrazidecarbonylmethoxy)-26,28-dihydroxycalix[4]arene (HCC4) was employed as a chromogenic sensing probe selective for Pb(II) and Cr2O7 2? ions among a series of various ions such as Li(I), Na(I), K(I), Rb(I), Ba(II), Sr(II), Al(III), Cd(II), Co(II), Cu(II), Hg(II), Ni(II), Pb(II) and Zn(II) as well as Cr2O7 2?, CH3CO2 ?, Br?, Cl?, F?, I?, ClO4 ? and NO3 ? that have been examined by UV-visible and fluorescence spectroscopic techniques. The HCC4 in DCM-MeCN system forms 2:1 (ligand-metal) complex with Pb(II). It also shows 2:1 stoichiometry with Cr2O7 2?. The complexation phenomenon has been confirmed by FTIR spectroscopy that favors the selective nature of HCC4 with Pb(II) and Cr2O7 2?. Thermal gravimetric analysis (TGA) also supports its utility in drastic conditions. 相似文献
53.
Alberto Castellón Serrano José Antonio Cuenca Mira Cándido Martín González 《代数通讯》2013,41(10):4699-4706
This work, jointly with [9], completes the structure theory and classification of the Jordan H *- triple systems. The problem of describing the Jordan H *-triple systems is reduced in [5] to that of describing the topologically simple ones. Ruling out the finite-dimensional case, we have that any of these H *-triples has an underlying triple system structure of quadratic type (and these can be fully described), or it is the H *-triple system associated to the odd part of a topologically simple Z2-graded Jordan H *-algebra, whose classification is given in [13]. 相似文献
54.
Let W → 𝔸 2 be the universal Weierstrass family of cubic curves over ?. For each N ≥ 2, we construct surfaces parameterizing the three standard kinds of level N structures on the smooth fibers of W. We then complete these surfaces to finite covers of 𝔸 2. Since W → 𝔸 2 is the versal deformation space of a cusp singularity, these surfaces convey information about the level structure on any family of curves of genus g degenerating to a cuspidal curve. Our goal in this note is to determine for which values of N these surfaces are smooth over (0, 0). From a topological perspective, the results determine the homeomorphism type of certain branched covers of S 3 with monodromy in SL2 (?/N). 相似文献
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Dr. Yujia Qing Mira D. Liu Denis Hartmann Dr. Linna Zhou Dr. William J. Ramsay Prof. Hagan Bayley 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(36):15841-15846
We report a single-molecule mechanistic investigation into 2-cyanobenzothiazole (CBT) chemistry within a protein nanoreactor. When simple thiols reacted reversibly with CBT, the thioimidate monoadduct was approximately 80-fold longer-lived than the tetrahedral bisadduct, with important implications for the design of molecular walkers. Irreversible condensation between CBT derivatives and N-terminal cysteine residues has been established as a biocompatible reaction for site-selective biomolecular labeling and imaging. During the reaction between CBT and aminothiols, we resolved two transient intermediates, the thioimidate and the cyclic precursor of the thiazoline product, and determined the rate constants associated with the stepwise condensation, thereby providing critical information for a variety of applications, including the covalent inhibition of protein targets and dynamic combinatorial chemistry. 相似文献
57.
Ahmed Ashour Yhiya Amen Toshinori Nakagawa Yasuharu Niwa Amira Mira Koichiro Ohnuki 《Natural product research》2020,34(12):1750-1755
AbstractAn aliphatic ester of hydroxysalicylic acid (6), reported for the first time from a natural source in addition to five known compounds were isolated from the fermented Carica papaya L. preparation, a commercialized functional food. The known compounds were identified as 5-hydroxymethylfurfuraldehyde (1), trans-caffeic acid (2), butyl 4-hydroxybenzoate (butylparaben) (3), lycopene (4), benzyl isothiocyanate (5). Compounds 1 and 3 were reported for the first time from Papaya fruits through this study. The new compound showed a moderate antioxidant activity and a potent hair growth stimulating activity in vitro. 相似文献
58.
Balazs Kobzi Erno Kuzmann Zoltan Homonnay Stjepko Krehula Mira Ristic Shiro Kubuki 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(2):579-586
Tin silicate glass without SnOx nanoparticles (SiO2·SnOx), a silica glass containing only SnOx nanoparticles (SiO2·SnOxNP) and the improved product, which combines the tin silicate glass with SnOx nanoparticles (SiO2·SnOx·SnOxNP) was prepared. For the structural analysis 119Sn Mössbauer spectroscopy and X-ray diffraction were applied. The 119Sn Mössbauer spectra showed that the SiO2·SnOx·SnOxNP sample had the largest SnII content (12.0%). It also had an outstanding methylene blue degradation with the first-order rate value with (18?±?2) × 10?3 min?1 with visible light irradiation. 相似文献
59.
Popovic M Janicijevic-Hudomal S Kaurinovic B Rasic J Trivic S 《Molecules (Basel, Switzerland)》2008,13(9):2249-2259
The major aim of this work was to investigate how alcohol-induced oxidative stress in combined chemotherapy changes the metabolic function of the liver in experimental animals. This research was conducted to establish how bromocriptine, haloperidol and azithromycin, applied to the experimental model, affected the antioxidative status of the liver. The following parameters were determined: reduced glutathione, activities of glutathione peroxidase, glutathione reductase, peroxidase, catalase, xanthine oxidase and lipid peroxidation intensity. Alanine transaminase was measured in serum. Alcohol stress (AO group) reduced glutathione and the activity of xanthine oxidase and glutathione peroxidase, but increased catalase and alanine transaminase activity. The best protective effect was achieved with the bromocriptine (AB1 group), while other groups had similar effects on the studied parameters. 相似文献
60.