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31.
Baran J Pawlukojć A Majerz I Malarski Z Sobczyk L Grech E 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2000,(9):1801-1812
The infra-red (IR), Raman (R) and inelastic incoherent neutron scattering (IINS) spectra, particularly in low frequency region, of the title ionic adduct were studied. It is shown that all low frequency vibrations (below 200 cm(-1)) of (CH3)2N groups of protonated 1,8-bis(dimethylamino)naphthalene (DMAN)--clearly observed in IINS spectra--are sensitive to the environment, i.e. to the type of counterion forming short contacts with C-H bonds of methyl groups. The internal frequencies were also calculated by ab initio method. The results are consistent with numerous observations of the counteranion effect on the geometry of the protonated DMAN. The conclusions are compared with structural and NMR studies reported recently for the 1,8-bis(dimethylamino)naphthalene with dichloromaleic acid (DMAN x DCM) adduct. The single crystal R polarized spectra taken over the frequency range 20-3200 cm(-1) were analyzed in detail. We have shown that a substantial difference in the IR spectrum of the dichloromaleic acid (DCM) anion in the DMAN adduct and in the potassium salt results from different geometries of OHO hydrogen bonds. In the case of potassium salt the chains of longer intermolecular hydrogen bonds are formed described by means of a double minimum potential. 相似文献
32.
V. M. Adamović 《Mikrochimica acta》1968,56(3):534-537
Zusammenfassung Zur Bestimmung von Toxaphen wurde die Weiszsche Ringofentechnik angewandt, wobei zum Auswaschen der Ringe eine Diphenylamin-Petrolätherlösung benutzt wird und zur Entwicklung der Farbe der Ringe eine kurzfristige Bestrahlung mit UV-Licht Anwendung findet. Die Grenzwerte der Bestimmungen sind 0,5 bis 2,5g Toxaphen mit einer Genauigkeit von 100±2%.Auf die Möglichkeit der Anwendung anderer aromatischer Amine für eine Reihe anderer Organochlorpestizide wird hingewiesen.
Vorgetragen auf dem 1. jugoslawischen Kongreß für Ernährung, Belgrad, 5. bis 7. Dezember 1966. 相似文献
Summary The Weisz ring oven technique was used for determining Toxaphene, whereby a diphenylamine-petroleum ether solution was employed for washing out the rings and a brief irradiation with UV light for the development of the color of the rings. The limiting values of the determinations are 0.5 to 2.5g Toxaphene with an accuracy of 100±2%.The possibility of the application of other aromatic amines for a series of other organo chlorinated pesticides is pointed out.
Vorgetragen auf dem 1. jugoslawischen Kongreß für Ernährung, Belgrad, 5. bis 7. Dezember 1966. 相似文献
33.
I. B. Plećaš A. D. Perić J. D. Drljača A. M. Kostadinović 《Journal of Radioanalytical and Nuclear Chemistry》1992,157(1):95-104
An optimization of mortar (as matrix), improved with bentonite clay, used for immobilization of radionuclides60Co,137Cs,85Sr and54Mn, is presented. A relatively simple mathematical model is given, which permits minimization of leach rate and permeability and maximization of compressive strength. An optimal solution, based on experimental data, is given. These results will be used for a future Yugoslav radioactive waste storing center. 相似文献
34.
At sufficiently high concentrations of methanol and of alkali salts in aqueous silica dispersions, the negative -potentials of the particles are decreased. This effect is more pronounced with lithium than with other alkali cations, and it is independent on the anion. The NMR spectra indicate lithium adsorption on silica from mixed solvents, but not in the absence of alcohol.Supported by a contract with the XMX Corporation, Burlington, Massachusetts, USA 相似文献
35.
36.
A study of chromium(III) ion adsorption on a stearic acid monomolecular layer (MML), spread on the surface of a51CrCl3 aqueous solution, is presented. From the analysis of the experimental results it can be concluded that MML saturation is achieved at CrCl3 concentrations above 10?6M. When the maximum adsorption pH value of Cr(III) ions on MML is 6.7, MML is completely ionized and chromium ion is bonded as Cr(OH) 2 + . The kinetics of Cr(III) ion adsorption on MML could be expressed as AS=A ∞ S (1?e?k t). 相似文献
37.
Summary On small columns filled with the inorganic cation-exchanger zirconium phosphate, Zn2+-Cd2+ were quantitatively and Ni2+-Co2+ partly separated. The exchanger was in the NH4+ form, and 0.5–4N NH4Cl served as eluent. With the exchanger in the H+ form, U02
2+ was separated from bivalent cations and ferric iron by stepwise elution with 0.1, 0.5 and 4N HCl solutions.
Zusammenfassung An kleinen Säulen des anorganischen Kationenaustauschers Zirkoniumphosphat wurden Zn2+ und Cd2+ quantitativ, Ni2+ und Co2+ teilweise getrennt. Der Austauscher lag in der NH4+-Form vor, 0,5-bis 4-n Ammoniumchlorid diente als Eluent. Mit der H+-Form des Austauschers wurde UO2 2+ von zweiwertigen Kationen und von Fe3+ durch schrittweise Elution mit 0,1-, 0,5- und 4-n Salzsäure getrennt.
Résumé On a séparé Zn2+-Cd2+ quantitativement et Ni2+-Co2+ partiellement sur de petites colonnes remplies de phosphate de zirconium comme échangeur minéral cationique. L'échangeur se trouvait sous forme NH4+ et l'on a pris NH4Cl 0,5-4N comme éluant. Avec l'échangeur sous forme H+, on a séparé UO2 2+ des cations bivalents et de l'ion ferrique par élution graduelle avec des solutions chlorhydriques 0,1, 0,5 et 4N.相似文献
38.
Tomislav P. Živković 《Journal of mathematical chemistry》2002,32(1):39-71
Interaction of quantum system S
a
described by the generalised × eigenvalue equation A|
s
=E
s
S
a
|
s
(s=1,...,) with quantum system S
b
described by the generalised n×n eigenvalue equation B|
i
=
i
S
b
|
i
(i=1,...,n) is considered. With the system S
a
is associated -dimensional space X
a
and with the system S
b
is associated an n-dimensional space X
n
b
that is orthogonal to X
a
. Combined system S is described by the generalised (+n)×(+n) eigenvalue equation [A+B+V]|
k
=
k
[S
a
+S
b
+P]|
k
(k=1,...,n+) where operators V and P represent interaction between those two systems. All operators are Hermitian, while operators S
a
,S
b
and S=S
a
+S
b
+P are, in addition, positive definite. It is shown that each eigenvalue
k
i
of the combined system is the eigenvalue of the × eigenvalue equation
. Operator
in this equation is expressed in terms of the eigenvalues
i
of the system S
b
and in terms of matrix elements
s
|V|
i
and
s
|P|
i
where vectors |
s
form a base in X
a
. Eigenstate |
k
a
of this equation is the projection of the eigenstate |
k
of the combined system on the space X
a
. Projection |
k
b
of |
k
on the space X
n
b
is given by |
k
b
=(
k
S
b
–B)–1(V–
k
P})|
k
a
where (
k
S
b
–B)–1 is inverse of (
k
S
b
–B) in X
n
b
. Hence, if the solution to the system S
b
is known, one can obtain all eigenvalues
k
i
} and all the corresponding eigenstates |
k
of the combined system as a solution of the above × eigenvalue equation that refers to the system S
a
alone. Slightly more complicated expressions are obtained for the eigenvalues
k
i
} and the corresponding eigenstates, provided such eigenvalues and eigenstates exist. 相似文献
39.
J. Jureta S. Cvejanović M. Kurepa D. Cvejanović 《Zeitschrift für Physik A Hadrons and Nuclei》1982,304(2):143-153
A high resolution electron impact threshold spectroscopy technique was used to examine the excitation of Cl2 in the 2–14 eV region. This study complements previous photon absorption and emission measurements, because it is capable of detecting transitions which are optically forbidden. In the region up to 7.5 eV, broad dissociative structures are correlated with optically active valence states, although relative intensities in the threshold spectrum differ considerably and indicate a substantial contribution from the optically forbidden transitions. At 7.46 eV a series of 5 equidistant sharp peaks is detected and interpreted as arising from the2 π g Feshbach resonance, which differs from the ground state positive ion Cl 2 + by a pair of Rydberg electrons: (4sσ)2. The decay channels responsible for the appearance of the resonance in a threshold spectrum are discussed and it is suggested that they include several valence states of the (2431) and (2341) configurations, whose potential energy curves cross the Cl 2 ? ,2πg curve in the region of energy at which the resonance state is formed. At higher incident electron energies and up to ionisation, Rydberg states predominate, starting with (2430) 4s3,1 π g states detected for the first time. The absence of broad peaks above 8 eV and the irregular appearance of Rydberg bands is consistent with the strong Rydberg-valence configuration mixing proposed by Peyerimhoff and Buenker. Where our resolution permits comparison, good general agreement is found with recent synchrotron radiation absorption measurements of optically allowed transitions. 相似文献
40.
Zusammenfassung Die analytische Bestimmung der Metalle, des Dipyridyls und der Chloride in Oxo-chloro-alkoxo-dipyridyl-Komplexverbindungen des Niobs und Tantals wurde beschrieben. Eine modifizierte Methode der Dipyridylanalyse, wie auch der Chloridbestimmung in Gegenwart von Dipyridyl wurde angegeben. Die radiometrische Metallbestimmung in Extraktionsverbindungen von Niob und Tantal mit Di-oktyl-methylenbis-phosphonsäure wurde dargelegt.
Vorgetragen beim Symposium für analytische Chemie in Graz, 29. September bis 1. Oktober 1965. 相似文献
Summary The analytical determination of metals, dipyridyl and chlorides in oxochloro-alkoxo-dipyridyl complex compounds of niobium and tantalum is described. A modified procedure of the dipyridyl analysis and also of the determination of chloride in the presence of dipyridyl is given. The radiometric determination of the metals in extraction compounds of niobium and tantalum with di-octyl-methylene-bis-phosphonic acid is discussed.
Résumé On décrit le dosage des métaux, du dipyridyle et des chlorures dans les composés complexes oxo, chloro, alcoxo, dipyridyle, du niobium et du tantale. On indique une méthode modifiée pour le dosage de dipyridyle ainsi que pour la détermination des chlorures, en présence de dipyridyle. On décrit le dosage radiométrique des métaux dans les produits d'extraction du niobium et du tantale par l'acide di-octyl-méthylène-bis-phosphonique.
Vorgetragen beim Symposium für analytische Chemie in Graz, 29. September bis 1. Oktober 1965. 相似文献