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131.
The reactions are reported between selenite and 1,2-dimercaptoethane (DME) or thioacetic acid (TAA) to form moderately stable derivatives having an enhanced absorptions in the 230–360 nm region in combining molar ratios 3:2 and 4:1, respectively. Both reactions invariably yield one product corresponding to the selenium-containing derivative of DME or TAA. The formation of products is a pH dependent process. The equilibrium constants of reactions between selenite and DME or TAA were measured. 相似文献
132.
CM Thaker S Rayaprol Krushna Mavani DS Rana MS Sahasrabudhe SI Patil DG Kuberkar 《Pramana》2002,58(5-6):1035-1039
The effect of simultaneous substitution of a fluctuating cation and a divalent cation in LaMnO3 perovskite modifies the properties of the material to exhibit large valence colossal magnetoresistance (CMR) effect. A good
example of these properties is (La1−2x
Pr
x
Ca
x
)MnO3 (LPCMO) type CMR material. In this communication it is reported that, with the increase in x (for x=0.1, 0.15, 0.2), the T
c varies between 100 and 120 K with improvisation in metal-insulator transition. Interestingly, resistance increases with x from few hundred ohms to few kilo ohms with corresponding decrease in the unit cell volume. The results of the studies using
X-ray diffraction (XRD), electrical resistivity, magnetoresistance and ac susceptibility measurements on LPCMO samples for
understanding the structural, transport and magnetic properties are discussed in detail. 相似文献
133.
Konstantin Mischaikow Marian Mrozek Pawel Pilarczyk 《Foundations of Computational Mathematics》2005,5(2):199-229
We introduce an efficient algorithm to compute the homomorphism
induced in (relative) homology by a continous map.
The algorithm is based on a cubical approximation of the map
and the theory of multivalued maps.
A software implementation of the algorithms introduced in this paper
is available at [27]. 相似文献
134.
Daniel Vegh Marian Landl Renata Pavlovicova Hans Kuzmany Peter Zalupsky 《Chemistry of Heterocyclic Compounds》1995,31(10):1238-1240
New phihalocyanine analogues were prepared based on 2,5-diamond-3,4-dicyanothiophene and diaminomaleo-nitrile.Department of Organic Chemistry, Slovak Technical University, Bratislava, Slovakia. Institute für Festkörperphysik der Universität Wien, Wien, Austria. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1409–1411, October, 1995. Original article submitted September 24, 1995. 相似文献
135.
136.
137.
The electroreduction of bovine serum albumin (BSA) in pH 7.4 solution was studied at the hanging mercury drop electrode by double potential step chronocoulometry and cyclic voltammetry, and at a mercury pool electrode by controlled potential coulometry. The proposed mechanism involves reduction of an adsorbed monolayer of BSA (maximum coverage 3.3 μC?2); at short times 3 or 4 disulfide bonds are reduced, the product remains adsorbed and may be reoxidized. On the coulometric time scale (hours) 8 or 9 of the total 17 disulfide bonds are broken and an insoluble product which cannot be oxidized is formed. 相似文献
138.
Miljenko Perić Mirjana Mladenović Jasenka Fejzo Christel M. Marian Pablo J. Bruna 《Chemical physics letters》1982,88(6):547-552
The results of an ab initio study of the vibronic and rotational structure in the 2Π state of HNO+ are presented. It is shown that the absorption spectrum at 7200 Å observed by Herzberg could be caused by the transition from the ground to the first excited electronic state of HNO+ 相似文献
139.
Marian Grabowski 《Letters in Mathematical Physics》1984,8(6):455-458
A new proof of the indeterminacy relation of the standard energy deviation and lifetime of a pure quantum state is given by means of the Mandelstam-Tamm inequality. 相似文献
140.