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531.
PL. RM. Palaniappan K. S. Pramod V. Vijayasundaram 《Journal of Applied Spectroscopy》2008,75(5):752-758
Zinc is an essential metal for different physiological functions and becomes toxic when elevated concentrations are introduced
into the environment. In the present study, an attempt is made to analyze zinc-induced biochemical changes in the liver tissues
of freshwater fingerlings of Labeo rohita using Fourier Transformation Infrared Spectroscopy. Several important features have
been observed in the FTIR spectra of zinc-intoxicated liver tissues, namely, altered membrane lipid, altered protein profile,
and increased glycogen content, indicating an alteration in the lipid and protein profiles leading to modification in membrane
composition. Further, it is observed that acute exposure to zinc causes some alteration in protein profile with a decrease
in α-helix and an increase in random coil structure. Treatment with the chelating agent D-penicillamine reduces the biochemical
contents in the liver tissues. This shows that D-penicillamine is a good antidote for zinc toxicity.
Published in Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 5, pp. 746–752, September–October, 2008. 相似文献
532.
Francis Comets Francesco Guerra Fabio Lucio Toninelli 《Journal of statistical physics》2005,120(1-2):147-165
We study a spin system on a large box with both Ising interaction and Sherrington-Kirpatrick couplings, in the presence of an external field. Our results are: (i) existence of the pressure in the limit of an infinite box. When both Ising and Sherrington-Kirpatrick temperatures are high enough, we prove that: (ii) the value of the pressure is given by a suitable replica symmetric solution, and (iii) the fluctuations of the pressure are of order of the inverse of the square of the volume with a normal distribution in the limit. In this regime, the pressure can be expressed in terms of random field Ising models. 相似文献
533.
Rinaldo M. Colombo Graziano Guerra Veronika Schleper 《Archive for Rational Mechanics and Analysis》2016,219(2):701-718
We prove a rigorous convergence result for the compressible to incompressible limit of weak entropy solutions to the isothermal one dimensional Euler equations. 相似文献
534.
Denis Lima Guerra Claudio Airoldi Kaline S. de Sousa 《Applied Surface Science》2008,254(16):5157-5163
Kaolinite-bearing clay samples from Perus, São Paulo state, Brazil, were used for chemical modification process with dimethyl sulfoxide and organofunctionalized with the silyating agent (RO)3Si(CH2)3NH(CH2)2NH2 in the present study. The resulting material and natural kaolinite were subjected adsorpion process with Cu(II) and Zn(II) from aqueous solution at pH 6.0 and controlated temperature of 298 K. The Langmuir adsorption isotherm model has been applied to fit the experimental data. The results showed that the chemical modification process increases the basal spacing of the natural kaolinite from 0.711 to 0.955 nm. The energetic effects caused by Cu(II) and Zn(II) interactions were determined through calorimetric titration at the solid–liquid interface and gave a net thermal effect that enabled the calculation of the exothermic values and the equilibrium constant. 相似文献
535.
Daniel Hernndez‐Guerra Anna Hlava
kov Chiranan Pramthaisong Ilaria Vespoli Radek Pohl Tom Slanina Ullrich Jahn 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(36):12570-12575
A mild, atom‐economic, and metal‐free α‐C?H amination of ethers using relatively stable nonafluorobutanesulfonyl (nonaflyl, Nf) azide as the aminating reagent to give N‐sulfonyl hemiaminals is reported. This enables unprecedented C(sp3) difunctionalization reactions, leading to diverse functionalized amino group containing compounds starting from simple ethers in one pot. 相似文献
536.
Renan B. Guerra Luis S. C. Huamaní Juan C. Tenorio Willian M. Guimares Juliano A. Bonacin Andr Luiz Barboza Formiga 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(10):1359-1371
The crystal structures of the solid form of solvated 2,6‐bis(1H‐imidazol‐2‐yl)pyridine (H2dimpy) trihydrate, C11H9N5·3H2O·[+solvent], I , and its hydrate hydrochloride salt 2‐[6‐(1H‐imidazol‐2‐yl)pyridin‐2‐yl]‐1H‐imidazol‐3‐ium chloride trihydrate, C11H10N5+·Cl?·3H2O, II , are reported and analysed in detail, along with potentiometric and spectrophotometric titrations for evaluation of the acid–base equilibria and proton‐coupled electron‐transfer reactions. Compound I crystallizes in the high‐symmetry trigonal space group P3221 with an atypical formation of solvent‐accessible voids, as a consequence of the 32 screw axis in the crystallographic c‐axis direction, which are probably occupied by uncharacterized disordered solvent molecules. Additionally, the trihydrated chloride salt crystallizes in the conventional monoclinic space group P21/c without the formation of solvent‐accessible voids. The acid–base equilibria of H2dimpy were studied by potentiometric and spectrophotometric titrations, and the results suggest the formation of H3dimpy+ (pKa1 = 5.40) and H4dimpy2+ (pKa2 = 3.98), with the electrochemical behaviour of these species showing two consecutive irreversible proton‐coupled electron‐transfer reactions. Density functional theory (DFT) calculations corroborate the interpretation of the experimental results and support the assignment of the electrochemical behaviour. 相似文献
537.
Stefania Pragliola Chiara Costabile Mariagrazia Napoli Gaetano Guerra Pasquale Longo 《Macromolecular Symposia》2006,234(1):128-138
Olefin-diene copolymerizations in the presence of C2 symmetric zirconocene rac-[CH2(3-tert-butyl-1-indenyl)2]ZrCl2/MAO catalytic system have been reported and rationalized by experimental and molecular modeling studies. Ethene gives 1,2-cyclopropane and 1,2-cyclopentane, 1,3-cyclobutane, and 1,3-cyclopentane units in copolymerization with 1,3-butadiene, 1,4-pentadiene, and 1,5-hexadiene, respectively. Propene-1,3-butadiene copolymerizations lead to 1,2 and 1,4 butadiene units and to a low amount of 1,2-cyclopropane units. 相似文献
538.
539.
Pragliola S Milano G Guerra G Longo P 《Journal of the American Chemical Society》2002,124(14):3502-3503
An unprecedented cyclopropanation by cyclopolymerization reaction is presented. In particular, catalytic copolymerization processes of ethene and butadiene lead with high trans selectivity to a complete cyclocopolymerization of butadiene units. Ethene-based copolymers including cyclopropane and cyclopentane rings, which can be relevant to polyolefin applications, are obtained with high yields. Several aspects relative to the mechanism of this cyclocopolymerization reaction, including the high stereoselectivity, are discussed. 相似文献
540.
Simultaneous high energy lasing in the N2 first and second positive systems is reported. 20.5 mJ (1.5 MW) UV and 5 mJ (0.4 MW) IR laser pulses were produced in pure N2. The design is open and easy to improve. 相似文献