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991.
Irina C. Covaci Petre Ionita Miron T. Caproiu Radu Socoteanu Titus Constantinescu Alexandru T. Balaban 《Central European Journal of Chemistry》2003,1(1):53-64
Starting from N-hydroxyphthalimide (5) and 1,3-dibromopropane (6) we obtained 1,3-bis(phthalimidooxy)propane (7) which led
to 1,3-bis(aminooxy)propane dihydrochloride (8). From its reaction with picryl chloride or 4-cyano-2,6-dinitrochlorobenzene,
the two title compounds (4b, 4a) were obtained.
1H-NMR and 13C-NMR spectra are presented. For comparison with the analogous N-methoxy-2,6-dinitro-4-R-anilines 1a, 1b (R=CN or R=NO2), wer report the hydrophobic characteristics (by RPTLC), electronic spectra for the neutral compounds and their anions, pK
a
values, and the behavior towards oxidizers (DPPH, PbO2, Pb(CH3COO)4, KMnO4 and Ag2O); DPPH converts compounds 1a, 1b and 4a, 4b into betainic structures 2a, 2b respectively. 相似文献
992.
Măruţoiu Constantin Filip Miuţa Tigae Cristian Coman Virginia Grecu Rodica Marcu Gheorghe 《平面色谱法杂志一现代薄层色谱法》2003,16(3):183-185
JPC – Journal of Planar Chromatography – Modern TLC - A stationary phase for thin-layer chromatography has been prepared by attaching 1-octene to alumina R. This stationary phase has... 相似文献
993.
Adrian Constantin 《Annali di Matematica Pura ed Applicata》1995,168(1):237-299
In this paper we consider sufficient conditions for the continuability of solutions for perturbed differential equations. We obtain also some results for the global existence of solutions for differential inclusions and for stochastic differential equations of McShane and Ito type. We give an application to the global inversion of local diffeomorphisms. 相似文献
994.
995.
996.
SU(2) andSU(1,1) algebra eigenstates: A unified analytic approach to coherent and intelligent states
Constantin Brif 《International Journal of Theoretical Physics》1997,36(7):1651-1682
We introduce the concept of algebra eigenstates which are defined for an arbitrary Lie group as eigenstates of elements of
the corresponding complex Lie algebra. We show that this concept unifies different definitions of coherent states associated
with a dynamical symmetry group. On the one hand, algebra eigenstates include different sets of Perelomov's generalized coherent
states. On the other hand, intelligent states (which are squeezed states for a system of general symmetry) also form a subset
of algebra eigenstates. We develop the general formalism and apply it to theSU(2) andSU(1,1) simple Lie groups. Complete solutions to the general eigenvalue problem are found in both cases by a method that employs
analytic representations of the algebra eigenstates. This analytic method also enables us to obtain exact closed expressions
for quantum statistical properties of an arbitrary algebra eigenstate. Important special cases such as standard coherent states
and intelligent states are examined and relations between them are studied by using their analytic representations. 相似文献
997.
G. Tsoupras C. Hetru B. Luu M. Lagueux E. Constantin J.A. Hoffmann 《Tetrahedron letters》1982,23(19):2045-2048
Newly-laid eggs of migratory locust contain as the major ecdysteroid conjugate donated by the female to its offspring the 22-adenosinemonophosphoric ester of 2-deoxyecdysone; in 8 days old embryos, the major ecdysteroid is the 3-phosphate of 3-epi 2-deoxyecdysone. 相似文献
998.
Emilia Constantin Yoichi Nakatani Guy Ourisson Raymond Hueber Gérard Teller 《Tetrahedron letters》1980,21(49):4745-4746
Direct introduction of diacyl-lecithins in the ionization chamber on a gold support gives the molecular ion and structurally significant fragments; the same is true with unprotected small polypeptides. 相似文献
999.
Constantin Bolcu Gabriela Vlase Titus Vlase Paul Albu Nicolae Doca Eugen Şisu 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1409-1414
Polymeric materials by polyaddition reaction between aminated maltose and methylene diisocyanate, in different molar ratio, were synthesized. Aminated maltose was obtained by functionalization at the reductive end with methylene dianiline, under soft reductive conditions. The addition reaction was certified by comparative FTIR and Raman spectra of reactants and obtained materials. The thermooxidative stability of these materials was established under non-isothermal conditions. The thermal stability decreases by increasing the isocyanate/aminated maltose molar ratio. 相似文献
1000.