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151.
Rosanna Toniolo Sabina Susmel Nicolò Dossi Andrea Pizzariello Marzia Martinis Gino Bontempelli 《Electroanalysis》2010,22(6):645-652
A porous gold electrode supported on one face of an ion‐exchange membrane, acting as a solid polymer electrolyte (SPE), is proposed as an amperometric sniffer for monitoring the aldehyde content in the headspace in equilibrium with lipid samples, in order to gain indication of their state of turning rancid It was used as a detector for a flow injection system in which aldehydes were injected, after preconcentration by solid phase microextraction on a SPME fiber from the gas phase standing above thermostated samples and subsequent desorption by heating. Repeatable (±4.5%) sharp peaks were detected over a wide linear concentration range (0.5–200 ppm). A detection limit of about 0.03 ppm was inferred for a signal‐to‐noise ratio of 3, referred to hexylaldehyde (used as prototype) dissolved in squalene or vegetable oils samples. This approach was applied to the determination of volatile aldehydes from some partially oxidized cereal oils and the results found were compared with both the corresponding peroxide values and their aldehyde content determined by a conventional spectrophotometric method. 相似文献
152.
153.
Taking Coulomb and proximity potentials as the interacting barrier we have studied the cold valley in the radioactive decay
of 244–260Fm isotopes. It is found that in addition to alpha particle minima, other minima occur at S, Ar and Ca clusters. We have computed
the half-lives and other characteristics of different clusters emitted from these parents treating parent, daughter and emitted
cluster as spheres. Our study reveals that most of these parents are unstable against alpha and heavy cluster (46Ar, 48,50Ca) emissions and stable against light cluster emission, except 8Be from 244–248Fm isotopes. The most probable clusters from these parents are predicted to be 46Ar, 48,50Ca which indicate the role of doubly or near doubly magic clusters (Z = 20, N = 28) and also stress the role of doubly magic 208Pb daughter. The computed half-lives for alpha decay are in good agreement with the experimental data. It is found that the
presence of neutron excess in the parent nuclei slows down the cluster decay process. The effect of quadrupole (β
2) and hexadecapole (β
4) deformations of parent and fragments on half-lives are also studied. It is found that inclusion of β
2 and β
4 reduces the height and shape of the barrier (increases barrier penetrability) and hence the half-life decreases. 相似文献
154.
Alice?C.?Niemeyer Sabina?B.?PannekEmail author Cheryl?E.?Praeger 《Archiv der Mathematik》2012,98(2):105-114
We call an element of a finite general linear group GL(d, q) fat if it leaves invariant and acts irreducibly on a subspace of dimension greater than d/2. Fatness of an element can be decided efficiently in practice by testing whether its characteristic polynomial has an irreducible
factor of degree greater than d/2. We show that for groups G with SL(d, q) ≤ G ≤ GL(d, q) most pairs of fat elements from G generate irreducible subgroups, namely we prove that the proportion of pairs of fat elements generating a reducible subgroup,
in the set of all pairs in G × G, is less than q
−d+1. We also prove that the conditional probability to obtain a pair (g
1, g
2) in G × G which generates a reducible subgroup, given that g
1, g
2 are fat elements, is less than 2q
−d+1. Further, we show that any reducible subgroup generated by a pair of fat elements acts irreducibly on a subspace of dimension
greater than d/2, and in the induced action the generating pair corresponds to a pair of fat elements. 相似文献
155.
Dalia Sabina Cîmpean 《Applied mathematics and computation》2010,217(8):4141-4146
We obtain a result on stability of the linear differential equation of higher order with constant coefficients in Aoki-Rassias sense. As a consequence we obtain the Hyers-Ulam stability of the above mentioned equation. A connection with dynamical sytems perturbation is established. 相似文献
156.
157.
Aliev Ziya Sakhaveddin Musayeva Sabina Sahib Imamaliyeva Samira Zakir Babanly Mahammad Baba 《Journal of Thermal Analysis and Calorimetry》2018,131(2):1115-1123
Journal of Thermal Analysis and Calorimetry - A combination of sol–gel Pechini method and flame synthesis was used to prepare yttrium aluminate glass microspheres with the garnet composition... 相似文献
158.
159.
Novel Copper(II) Thiodibenzoic Acid Coordination Polymers by in situ Extrusion of Sulfur from 2,2′‐Dithiodibenzoic Acid and the Unique Oxidation of Disulfide to Sulfate 下载免费PDF全文
Salma B. Moosun Lisa H. Blair Simon J. Coles Sabina J. Laulloo Minu G. Bhowon 《无机化学与普通化学杂志》2015,641(5):890-895
Slow diffusion reaction of 2,2′‐dithiodibenzoic acid (dtdb) with CuCl2 in the presence of N‐donor ligands results in the formation of different coordination polymers where both S–S and C–S scission and oxidation of S is observed. X‐ray diffraction analysis of [Cu(tdb)(phen)(H2O)]2 · 2H2O.2DMF] ( 1 ), [Cu(tdb)(py)2(H2O)]2 ( 3 ), and [Cu(tdb)(bipy)(H2O)]2 · 0.5H2O ( 4 ) (tdb = thiodibenzoic acid, phen = phenanthroline, py = pyridine, bipy = 2,2′‐bipyridine) show that the metal ions are coordinated to the carboxylate oxygen atoms of the in situ generated tdb ligand in a monodenate fashion. In [Cu(phen)(SO4)2(H2O)2]n ( 2 ) and [Cu(bipy)(SO4)2(H2O)2]n ( 5 ), the sulfur is oxidized to sulfate ions prior to coordination with the metal. Complex 1 has a dimeric structure with π–π interactions between the phen ligands, whereas 3 and 4 form 1D polymeric chains. 相似文献
160.
Journal of Nonlinear Science - In this paper, we study the dynamics of nonlinear random walks. While typical random walks on networks consist of standard Markov chains whose static transition... 相似文献