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1.
The conditions of thermal decomposition of the hippurates of Y, La and the light lanthanides from Ce(III) to Gd have been studied. When heated, the Y, Ce(III), Pr and Gd complexes decomposed in two stages, those of La, Sm and Eu in three stages, and that of Nd in four stages, the oxides finally being formed. The complexes lost crystallization water to form anhydrous (Nd) or hydrated salts, and then decomposed to oxides directly (Y, Ce(III), Pr(III) and Gd) or with intermediate formation of Ln2O2CO3 (La, Nd, Sm and Eu). The temperature of oxide formation varied periodically with the ionic potential in the lanthanide series.
Zusammenfassung Die Bedingungen der thermischen Zersetzung der Hippurate von Y, La und der leichten Lanthanide von Ce(III) bis Gd wurden untersucht. Beim Aufheizen zersetzen sich die Komplexe von Y, Ce(III), Pr und Gd in zwei Schritten, die von Sm und Eu in drei Schritten und der von Nd in vier Schritten zu den Oxiden. Die Komplexe verlieren Kristallwasser unter Bildung wasserfreier (Nd) oder hydratisierter Salze und zersetzen sich dann direkt (Y, Ce(III), Pr(III), Gd) oder über Ln2O2CO3 (Ln, Nd, Sm, Eu) zu den Oxiden. Die Temperatur der Oxidbildung verändert sich periodisch mit abnehmenden Ionenpotential in der Lanthanidenreihe.

, . , , , , — , — , . , , (, , ) Ln2O2CO3 (, , ). .
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2.
Fine particle cobalt doped-Fe2O3 and Mn-Zn ferrites have been prepared by the thermal decomposition of N2H5Co x Fe1–x (N2H3COO)3.H2O wherex=1–10 atom% and (N2H5)3MnxZn1–x Fe2(N2H3COO)9· 3H2O wherex=0.2–0.8, respectively. Formation of these oxide materials has been confirmed by thermogravimetry and X-ray powder diffraction patterns. The fine particle nature of these oxide materials is evident from particle size analysis and surface area measurements.
Zusammenfassung Mit fein verteiltem Kobalt versetztes-Fe2O3 sowie Mn-Zn Ferrite wurden durch thermische Zersetzung von N2H5Co x Fe1–x (N2H3COO)3·H2O mit jc=1–10 Atomprozent bzw. (N2H5)3Mn x Zn1–x Fe2(N2H3COO)9·3H2O mitx=0,2–0,8 hergestellt. Die Bildung dieser Oxidstoffe wurde durch Thermogravimetrie und Pulverdiffraktionsmethoden bekräftigt. Die Feinkornstruktur dieser Oxidstoffe wird durch Korngrößenverteilungs- und Oberflächenmessungen augenscheinlich.

N2H5Co x Fe1–x (N2H3COO)3·H2O, x-1–10 %, (N2H5)3Mn x Zn1–x Fe2(N2H3COO)9 · 3H2O, x=0,2–0,8, , , -Fe2O3 Mn-Zn . . .
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3.
The oxidation of aliphatic ketones by thallium(III) sulfate in aqueous medium has been studied from the point of view of the temperature effect and the enthalpy-entropy relationship. It has been found that the isokinetic relationship is fulfilled in this case.
(III) - . , .
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4.
The rates for reactions between methyl radicals and 1-heptene have been studied and the kinetic parameters log (k1/dm3 mol–1s–1)=8.4±0.1–(33.3±1.0) kJ/RT In 10 and log (k3/dm3 mol–1s–1)=7.5±0.2)–29.7±1.5) kJ/RT In 10 have been determined for addition and allyl-hydrogen abstraction, respectively.
1- log (k1/3 –1 –1)=(8,4±0,1)-(33,3±1,0) kJ/RT In 10 log (k3/3 –1 –1)=(7,5±0,2)–(29,7±15) kJ/RT In 10 .
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5.
Résumé Les interprétations classiques des paramètres cinétiques en analyse thermique (ATD, TG) sont généralement déduites d'expériences réalisées en régime isotherme. Dans le présent travail, nous proposons une méthode qui prend en considération des conditions non isothermes et, en particulier, des vitesses de montée en température élevées. La nouvelle équation de base donnant la vitesse de réaction, introduit dans la relation d'Arrhenius le nombre de germes par unité de volume dans l'échantillon à la températureT, ce nombre étant une fonction de la vitesse de montée en température. Ce modèle permet de rendre compte, en particulier, de la courbure de Ln (/sT c 2 ) en fonction de l'inverse (1/Tc) de la température du pic de cristallisation pour les grandes vitesses en ATD. Ce modèle est appliqué de façon satisfaisante aux résultats ATD obtenus sur le composé amorphe CdGeAs2.
The normal interpretation of kinetic parameters in thermal analysis (DTA, TG) are deduced from isothermal experiments. In the present work, we propose a method which takes into account non-isothermal conditions, particularly high heating rates are considered. The new basic equation for the reaction rate includes in the Arrhenius relation the number of nuclei per unit volume in the sample at temperatureT. This number is a function of the heating ratev. This model allows, in particular, to account for the curvature of the variation of ln (v/T c 2 ) as a function of the inverse of the crystallization peak temperature (1/Tc) for high heating rates in DTA experiments. This model is applied successfully to DTA results on an amorphous CdGeAs2 compound.

Zusammenfassung Die klassischen Deutungen der kinetischen Parameter der Thermoanalyse (DTA, TG) werden im Allgemeinen aus isotherm geführten Versuchen abgeleitet. In der vorliegenden Arbeit wird eine Methode vorgeschlagen, welche nicht-isotherme Bedingungen und besonders hohe Temperaturanstiegsgeschwindigkeiten berücksichtigt. Die neue Grundgleichung zur Angabe der Reaktionsgeschwindigkeit führt in die Arrheniussche Funktion die Keimzahl je Volumeinheit in der Probe bei der TemperaturT ein, wobei diese Zahl eine Funktion der Geschwindigkeit des Temperaturanstieges ist. Dieses Modell gestattet besonders die Deutung der Krümmung von ln (/T c 2 ) als Funktion des Reziprokwertes(1/T c) der Temperatur des kristallisationspeaks bei hohen Aufheizgeschwindigkeiten in DTA-Untersuchungen. Dieses Modell konnte bei den DTA-Ergebnissen der amorphen Verbindung CdGeAs2 mit befriedigendem Ergebnis eingesetzt werden.

(, ) . , , , . . v. , ln (v/T c 2 ) (1/T c) . CdGeAs2.
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6.
The dissociation equilibrium between uncharged local anesthetic lidocaine (LC) and charged local anesthetic LC (LCH+) in a surface-adsorbed film was investigated by measuring the surface tension and pH of aqueous solutions of a mixture of hydrochloric acid and LC. The surface tension values decreased slightly with increasing total molality mt at 0X20.5, where X2 is the mole fraction of LC in the mixture, while they decreased rapidly with increasing mt at 0.5<X21. It was shown from the pH measurements that almost all LC molecules were changed into LCH+ ions by protonation at 0X20.5 and both forms coexisted only at 0.5<X21. The quantities of the respective LC and LCH+ transferred from the aqueous solution to the adsorbed film, i.e., their surface densities, were calculated by applying the thermodynamic equations derived to the surface tension and pH data. A greater quantity of LC than LCH+ existed in the adsorbed film at the coexisting composition. The partitioning behavior of LC and LCH+ in the adsorbed film was characterized by three composition regions: (1) slight partitioning of low surface-active LCH+ in the region at 0X20.5, (2) preferential partitioning of LC at 0.5<X2<around 0.7, and (3) negative partitioning of LCH+ at around 0.7X21. The present results clearly indicate that uncharged local anesthetics transfer into hydrophobic environments such as cell membranes more than charged ones.  相似文献   

7.
The frontal adsorption dynamics with the convex adsorption isotherm at a stage of parallel transfer, was numerically simulated. The change with time in the mean adsorption values a c in the adsorbent layers of short length L and corresponding concentrations c L at the outlet from L was calculated. Zeldovich"s equality, which suggests that the ratio of c L to a c is equal to the ratio of the inlet fluid phase concentration to the amount adsorbed at equilibrium, is fulfilled at L 0 over the interval of relative concentrations from 10–4 to 1. This indicates that Zeldovich"s equality is fulfilled as local at any limiting stage of mass transfer. The nonequilibrium dynamics of adsorption always has the finite L value at which the calculated c L and a c values approximately coincide with the a and c values of the equilibrium adsorption isotherm.  相似文献   

8.
Crystals of the -complex [C4H8N2(C3H5)4]2+[CuCl2] 2 (I) were prepared by ac electrochemical synthesis from copper and N,N,N,N-tetraallylpiperasinium chlorides in alcohol solution. Similar synthesis with the use of the metal and N,N,N,N-tetraallylpiperasinium bromides yielded the complex [C4H8N2(C3H5)4]2+[CuBr3]2– (II). Structures I and II were studied by X-ray diffraction (DARCh automated single-crystal diffractometer, MoK radiation). Crystals of I are triclinic, space group P1¯, a = 8.650(3) Å, b = 7.572(2) Å, c = 8.095(3) Å, = 100.45(2)°, = 83.91(2)°, = 99.89(2)°, V = 512.1(6) Å3, Z = 1. Crystals of II are orthorhombic, space group Pn21 a, a = 17.673(3) Å, b = 14.369(6) Å, c = 8.244(2) Å, V = 2093(2) Å3, Z = 4. In structure I, the potentially tetradentate N,N,N,N-tetraallylpiperasinium cation uses two centrosymmetric allyl groups for bonding with copper atoms, whose environment is completed to the trigonal-planar coordination with the chlorine atoms. The [C4H8N2(C3H5)4]2+[CuCl2] 2 groups are joined into a three-dimensional framework by weak hydrogen bonds. The inorganic fragment CuCl 2 is partially disordered, which appears as splitting of the positions of the copper atom and one of the chlorine atom. In compound II, the inorganic fragment occurs as an unusual trigonal-planar CuBr2– 3 anion; the N,N,N,N-tetraallylpiperasinium cation is not involved in metal coordination.  相似文献   

9.
Kinetic regularities in the reaction of triphenyl phosphite ozonide with several thioacetals in CH2Cl2 solution at –15°C have been studied. The consumption rate of ozonides is described by the kinetic equation W=k0[(C6H5O)3P·O3]+k1[(C6H5O)3P·O3][R1R2C(SR3)2] Rate constants k0 and k1 for the thioacetals: (CH3H7S)2CH2, (C6H5S)2CH2, (C6H5CH2S)2CH, (n=C12H25–S)2CH2, (C3H7S)2C(H)CH3, (C3H7S)2C(H)C6H5, (C3H7S)2C(CH3)C6H5 and (C3H7S)2C(H)C10H9, increases with increasing the electron-donating power of subtituents Ri.
CH2Cl2 –15°C. : W=k0[(C6H5O)3P·O3]+k1[(C6H5O)3P·O3][R1R2C(SR3)2] k0 k1 (C3H7S)2CH2, (C6H5S)2CH2, (C6H5CH2S)2CH2, (n-C12H25S)2CH2, (C3H7S)2C(H)CH3, (C3H7S)2C(H)C6H5, (C3H7S)2C(CH3)C6H5, (C3H7S)2C(H)C10H9. .
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10.
The transformations of 1,3- and 1,5-cycloctadiene under hydrogenation conditions were investigated. The main product of the reactions studied was Z-[3.3.0]bicyclooctene.
1,3- 1,5- . Z-[3.3.0].
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11.
    
The binding energy of CO on Rh is greater than that on Co. The difference in binding energy arises from the destabilization of the s band of Co following CO adsorption. Binding energies of CO on metals of Fe, Ni, Cu and Rh have been compared.
CO Rh , Co. ѕ Co CO. CO Fe, Ni, Cu Rh.
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12.
() () [M–Br]+ . .
Ionisation potentials (IP) of alkyl substituted brombenzenes and appearance potentials (AP) for [M–Br]+ ions were determined. IP are in a good accordance with inductive effects, whereas AP are discussed within field effect framework.
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13.
The values of thermodynamic functions of the following eight organic compounds under non-reacting conditions within the temperature range 298.15 – 550 K are given: N,N dimethylformamide, CHO · N(CH3)2; 4-nitro-1-chlorobenzene, Cl · C6H4 · NO2; sodiump-nitrophenoxide, NO2 · C6H4 · ONa; 1-methyl-2-pyrrolidone, 4,4-dinitrodiphenyl ether, (NO2 · C6H4)2O; 4,4-diaminodiphenyl ether, (NH2 · C6H4)2O; bis-(4-aminophenyl)methane, (NH2 · C6H4)2CH2; bis(4-maleic acidimidphenyl)methane, The relative enthalpy was obtained from calorimetric data by drop calorimetry. The heat capacity and relative entropy are functions derived from the foregoing. The equations of the temperature variation of the relative enthalphy were obtained by computer processing of the calorimetric data by the least squares method. The parameters of solid-liquid transitions were determined from the discontinuity of the temperature variation of the relative enthalpy.
Zusamenfassung Die Werte der thermodynamischen Funktionen folgender 8 organischer Verbindungen werden unter nicht-reagierenden Bedingungen im Temperaturbereich von 298.15 bis 550 K angegeben: Dimethylformamid, CHO · N(CH3)2;p-Nitrochlorbenzol, Cl · C6H4NO2; Natrium-p-Nitrophenoxid, NO2 · C6H4ONa; N-Methylpyrrolidon, 4-4-Dinitrodiphenyläther, (NO2 · C6H4)2O; 4-4-Diaminodiphenyläther, (NH2C6H4)2O; 4-- 4-Diaminodiphenylmethan, (NH2 · C6H4)2CH2; 4-4-bis-Maleinimid-Diphenylmethan, Die relative Enthalpie wird aus kalorimetrischen Daten der Temperaturgefällekalorimetrie erhalten. Die Wärmekapazität und die relative Entropie sind Funktionen der erwähnten Werte. Die Gleichungen der Temperaturänderung der relativen Enthalpie wurden mittels Computerverarbeitung der kalorimetrischen Daten, mit der Methode der kleinsten Quadrate erhalten. Die Parameter der fest-flüssig Übergänge wurden an Hand der Diskontinuität der Temperaturänderung der relativen Enthalpie bestimmt.

Résumé On donne les valeurs des fonctions thermodynamiques des 8 composés organiques suivants, en conditions non réactionnelles, dans l'intervalle de températures 298.15–550 K: diméthylformamide CHO · N(CH3)2,p-nitrochlorobenzène Cl · C6H4 · NO2,p-nitrophé noxysodium NO2 · C6H4 · ONa, N-méthylpyrrolidone dinitrodiphényl-4,4 éther (NO2 · C6H4)2O, diaminodiphényl-4,4 méthane (NH2 ·H 4CH2, 4-4 bis maléinimide diphénylméthane L'enthalpie relative a été obtenue à partir de données calorimétriques fournies par un calorimètre à chute. La chaleur spécifique et l'entropie relative sont des fonction dérivées de la précédente. Les équations donnant la variation de l'enthalpie relative en fonction de la température sont obtenues par traitement des données calorimétriques sur ordinateur par la méthode des moindres carrés. Les paramètres des transitions solide-liquide ont été déterminés à partir de la discontinuité de la variation de l'enthalpie relative avec la température.

, 298,15–550 , : — · N(CH3)2;- — l · 64 · NO2.- -NO2·64·ONa; N-—3·N··2·22; 4,4- — (NO2·64)2; 4,4- — (NH2·64)2; 4,4- — (NH2·64)22; 4,4-- —(64.N. . :. )22. . , . . - .
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14.
The interaction of the -bond system with the -electron system in molecules of type {ie427-01} is easily determined for the symmetrical CH3 group by isolating the -component from the system of three -bonds; CH3 is thus treated as a C=X quasivinyl group. The theory is extended to unsymmetrical groups.Read at the Symposium on Quantum Chemistry, Palanga, June 1965.  相似文献   

15.
The kinetic of thermal and thermo-oxidative degradation of polystyrene in the presence of bromine-containing flame retardants was investigated. It was shown that the kinetics is limited by diffusion in air and by the processes occurring at the interface in helium.The flame retardants affect the degradation of polystyrene both chemically and physically, and change the mechanism of the limiting stage to some extent.
Zusammenfassung Die Kinetik des thermischen und thermo-oxidativen Abbaus von Polystyren in Gegenwart bromhaltiger Flammschutzmittel wurde untersucht. Es wird gezeigt, dass die Reaktion durch die Diffusion in Luft bzw. durch die Grenzflächenvorgänge in Helium begrenzt wird.Die Flammschutzmittel beeinflussen den Abbau von Polystyren sowohl chemisch als auch physikalisch und verändern im gewissen Masse auch den Mechanismus des geschwindigkeitsbestimmenden Schritts.

. , , — . .
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16.
The semi-empirical configuration interaction treatment due to Pariser and Parr and to Pople has been modified by reducing the set of electronic interaction integrals to 11 and 12 and by limiting the number of configurations to 10. Hückel MOs are used as basis functions. The dependence of the resonance integral v on the interatomic distance R v is simulated by making v a quadratic function of the Hückel bond orders P v .
Zusammenfassung Eine Modifikation des semiempirischen CI-Verfahrens von Pariser, Parr und Pople wurde zur Behandlung von -Systemen herangezogen. Als Vereinfachung wurde der Grad der CI-Matrix auf zehn beschränkt und von den Elektronenwechselwirkungsintegralen nur 11 und 12 berücksichtigt. Hückel-MOs wurden als Basisfunktionen verwendet. Die Abhängigkeit des Resonanzintegrals v vom interatomaren Abstand R v wurde durch den Ansatz von v als quadratische Funktion der Hückel-Bindungsordnung P v angenähert.

Résumé Le procédé semi-empirique de l'interaction de configuration selon Pariser, Parr et Pople a été modifié en réduisant l'ensemble des intégrales d'interaction électronique à 11 et limitant le nombre des configurations à 10. Les fonctions de base sont des orbitales moléculaires selon Hueckel. La dépendance entre l'intégrale de résonance v et la distance interatomique R v est simulée en posant que v est une fonction quadratique des ordres de liaisons P v selon Hückel.
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17.
Five new CuII complexes of general formula [Cu2(Rdtc)tpmc](ClO4)3, (1)–(5), where tpmc and Rdtc refer to N,N,N,N-tetrakis(2-pyridylmethyl)-1,4,8,11-teraazacyclotetradecane and piperidine- (Pipdtc), 4-morpholine- (Morphdtc), 4-thiomorpholine- (Timdtc), piperazine- (Pzdtc) or N-methylpiperazine- (N-Mepzdtc) dithiocarbamates, respectively, have been prepared. Elemental analyses, conductometric and magnetic measurements, u.v./vis, i.r., e.p.r. and mass spectroscopy have been employed to characterize them. The complexes adopt an exo coordination of CuII ions and tpmc. The dithiocarbamate ion joins both the sulphur and the copper atoms acting as a bridging ligand The presence of different heteroatoms in the piperidine ring influences the (C=N) and (C=S) vibrations which decrease in the order of the complexes: Pipdtc>N-Mepipdtc>Pzdtc>Morphdtc>Timdtc ligands. Attention has been paid to the detailed mechanism of the mass spectral fragmentation of the complexes. The g eff factors of the complexes have been also estimated by e.p.r. spectra. Finally, the complexes obtained demonstrate microbiologycal activity against some bacteria.  相似文献   

18.
Zusammenfassung Diphenylphosphinsäureanilid-kalium wurde in Lösung von Dioxan erhalten und mit Alkylhalogeniden zu Diphenylphosphinsäure-alkylaniliden umgesetzt. Mit Methylenjodid entsteht N,N-Bis-[diphenylphosphinsäure]-N,N-diphenylmethylendiamid, während mit Äthylenbromid Acetylen und Diphenylphosphinsäureanilid erhalten wird. Mit Ph2P(O)Cl bzw. PhP(O)Cl2 erhält man N,N-Bis-[diphenylphosphinsäure]-N-phenyl-amid bzw. Phenylphosphonsäure-N,N-diphenyl-N,N-bis-[diphenylphosphinsäure]-diamid.  相似文献   

19.
Results are presented concerning the role of oxalic acid, salicylic acid and glycine as coimpregnation ingredients in preparation of Pd/Al2O3 catalysts from PdCl 4 2– and PdBr 4 2– solutions.
, , , Pd/Al2O3 PdCl 4 2– PdBr 4 2– .
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20.
17O,51V and31P NMR studies indicate that the anion structure of sodium vanadophosphate in an aqueous solution is close to that in crystals of the (CN3H6)8HPV14O42 7H2O salt.
17O,51V,31P , (CN3H6)8HPV14O42 7H2O.
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