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1.
2,4-Bipyridyl (2,4-bipy orL) complexes with cobalt(II), nickel(II) and copper(II) of the formulae M(2,4-bipy)2(CH3COO)2·2H2O (M(II) = Co, Ni, Cu), Co(2,4-bipy)2SO4·3H2O or Ni(2,4-bipy)2SO4·4H2O have been prepared and their IR and electronic (VIS) spectra are discussed. The thermal behaviour of the obtained compounds has also been studied. The intermediate products of decomposition at different temperatures have been characterized by chemical analysis and X-ray diffraction.We thank dr. A. Malinowska for performing VIS spectra. This work was supported by the KBN project No. PB 0636/P3/93/04.  相似文献   

2.
Summary Complexes of general formula MLmCl2 · nH2O, where M=cobalt(II) or nickel(II); L=2-(4-methyl, 2-pyridyl)-benzimidazole (mpbi), 2-(4-methyl, 2-pyridyl)benzothiazole (mpbt), 2-(4-methyl, 2-pyridyl)benzoxazole (mpbo), 2-(4-methyl, 2-quinolyl)benzoxazole (mqbo), or 2-(4-methyl, 8-quinolyl)benzoxazole (mqbo); m=1,2; n=0–3, were prepared and characterized by t.g.a., conductance and magnetic measurements, i.r. and diffuse-reflectance electronic spectra.All the ligands behave as bidentate and coordinate through the pyridine- and isoxazole-nitrogen atoms.The nickel complexes have distorted octahedral or fivecoordinate structures. The cobalt complexes arepseudo-tet- rahedral except Co(mpbo)2Cl2·2H2O where the metal is six-coordinate.  相似文献   

3.
The application of several metal phenyl compounds as active cocatalysts in the homogeneous metathesis of alkenes with WCl or MoCl is described. Promising results have been obtained by using Sn(C6H5)4, Sn(C6H5)3Cl, Pb(C6H5)4 and Pb(C6H5)3Cl.
- , WCl6 MoCl5. qH Sn(C6H5)4, Sn(C6H5)3Cl, Pb(C6H5)4 Pb(C6H5)3Cl.
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4.
Y. Zhao 《Chromatographia》1993,37(5-6):284-286
Summary The composition of 3,5-diBr-PADAP metal chelates was determined by liquid chromatography employing appropriate eluents and non-polar bonded stationary phase. The metal-to-ligand ratios were 12, 12 and 12 for Cu(II), Co(III) and Cr(III) respectively, and the V(V)-to-ligand ratio found to be 111 in V(V)-3,5-diBr-PADAP-H2O2 in the presence of H2O2. The results are in agreement with literature data.  相似文献   

5.
Summary The tetramethylthiourea (TMTU) complexes of cobalt(II) and nickel(II) halides have been studied in the solid state by electronic, i.r. and far i.r. spectroscopy and magnetochemically. The tetrahedral Co(TMTU)2X2 (X = Cl, Br, 1) and Ni(TMTU)2X2 (X = Cl, Br) complexes have normal magnetic moments, electronic spectra and crystal field parameters; Ni2 (TMTU)3I4 is diamagnetic. The cobalt complexes have normal (CoX) and (CoX) vibrational frequencies. Ni(TMTU)2Cl2 and Ni2(TMTU)3I4 have (NiX) frequencies corresponding to long or bridging Ni-X bonds, while Ni(TMTU)2Br2 has normal (NiBr) frequencies for terminal Ni-Br bonds. The (MS) frequencies are similar to those of cobalt(II) and nickel(II) complexes of other thioureas.  相似文献   

6.
Summary The copper(II), cobalt(II) and nickel(II) chloride and bromide complexes with the ligands 2-(2-quinolyl)-benzimidazole (qbi), 2-(4-methyl-2-quinolyl)benzimidazole (mqbi), 2-(4-methyl-8-quinolyl)benzothiazole (m'q'bt) have been prepared and characterized by analytical methods, magnetic measurements as well as by electronic absorption, e.s.r. and far i.r. spectra. Complexes of various stoichiometries have been isolated, namely MLX2 (all cobalt complexes with exception of the bromide qbi complex; the chloride and bromide nickel m'q'bt and mq'bt complexes), ML2X2 (M=Co,L=qbi and X=Br; M=Ni, L=mqbi, X=Cl or Br, M=Ni, L=qbi, X=Cl) and ML3X2(M=Ni, L=qbi or mqbi, X=Br). The cobalt ion has a distorted tetrahedral N2X2 coordination in all the CoLX2 complexes, whereas Co(qbi)2Br2 is six-coordinate. The following conclusions may be drawn for the nickel complexes: in those with the 11 metal-to-ligand molar ratio the metal ion is four-or five-coordinate; in those with the 12 and 13 ratios the metal ion is hexa-coordinate, being essentially bound to four nitrogen atoms with halogens, oxygens from water or methanol or nitrogen atoms (from the third ligand) occupying the axial positions.  相似文献   

7.
Summary This article describes some complexes of cobalt(III) with -mercaptopropylamine,N, N-dimethyl--mercaptopropylamme andN,N-dimethyl--mercaptoethylamine. The compounds are of stoichiometry [Co(ligand)3], [Co3(ligand)6]X (X=Cl or Br) and [Co(ligand)3]X3 (X=Cl or ClO4). -Mercaptopropylamine yields both chelated and non-chelated compounds while theN,N-dimethyl derivatives yield only non-chelated complexes. This behaviour contrasts with the results obtained with nickel(II).  相似文献   

8.
Seven complex compounds exhibiting the compositions Ni(en)3Ni(CN)4·H2O (I), Ni(en)3Ni(CN)4 (II),-Ni(en)2Ni(CN)4 (III), Ni(en)Ni(CN)4·2H2O (IV), Ni(en)Ni(CN)4 (V), Ni(en)2Ni(CN)4 · 2.5H2O (VI) and-Ni(en)2Ni(CN)4 (VII) were prepared from the system Ni-en-[Ni(CN)4]2–-H2O. These compounds were examined by the methods of infrared spectroscopy, X-ray powder diffractometry, UV-VIS reflectance spectroscopy, and also by the measurement of magnetic moments. The thermal stability, the stoichiometry of thermal decomposition and the mutual transformations were investigated with a derivatograph. The reactions proceeding according to the following schemes were observed if the system was heated to appropriate temperature: (I)(II)(III)(V)(IV) and (VI)(VII)(III)(V)(IV) Process (VII)(III) represents isomerization. The reversibility of the process (V)(IV) is due to the high hygroscopicity of the anhydrous complex. The changes in structure in the course of the individual processes are discussed.
Zusammenfassung Aus einem System Ni-en-[Ni(CN)4]2–-H2O wurden sieben Komplexe der Formeln Ni(en)3Ni(CN)4·H2O (I), Ni(en)3Ni(CN)4 (II),-Ni(en)2Ni(CN)4 (III), Ni(en)Ni(CN)4·2H2O (IV), Ni(en)Ni(CN)4 (V), Ni(en)2Ni(CN)4 · 2.5H2O (VI) und-Ni(en)2Ni(CN)4 (VII) hergestellt. Diese Verbindungen wurden mittels IR-Spektroskopie, Röntgenpulverdiffraktometrie, UV-Reflexionsspektroskopie und durch Messungen des magnetischen Momentes untersucht. Die Wärmestabilität, die Stöchiometrie des thermischen Zerfalles und die gegenseitigen Umwandlungen wurden mittels eines Derivatographen untersucht. Wird das System auf geeignete Temperaturen erhitzt, kann der Reaktionsverlauf durch folgendes Schema dargestellt werden: (I)(II)(III)(V)(IV) und (VI)(VII)(III)(V)(IV).Der Prozeß (VII)(III) verkörpert eine Isomerisierung. Die Umkehrbarkeit von Prozeß (V)(IV) ist auf die ausgeprägten Hygroskopieeigenschaften des wasserfreien Komplexes zurückzuführen. Es werden die im Ablaufe der einzelnen Prozesse vorgehenden Strukturveränderungen besprochen.

Ni- -[No(N)]2 -2 Ni(en)3Ni(CN)4 · 2 (I), Ni(en)3Ni(CN)4 (II),-Ni(en)2Ni(CN)4 (III), Ni(en)Ni(CN)4-2H2O (IV), Ni(en)Ni(CN)4 (V), Ni(en)2Ni(CN)4 · 2,5H2O (VI) -Ni(en)2Ni(CN)4 (VII). , , - , . , . (I)(II)(III)(V)(IV) (VI)(VII)(III)(V)(IV). (VII)(III) . (V)(IV) . .
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9.
Electrophilic substitutions Co(II) M(II) (M = Mn, Ni, Cu, Zn, Cd) in cobalt(II) hexacyanoferrate(II) gelatin-immobilized matrices in contact with aqueous solutions of corresponding chlorides MCl2 were studied. As a result of this contact, Co(II) was shown to be replaced to some extent by Ni(II), Cu(II), Zn(II), or Cd(II) and to give heteronuclear cobalt(II) hexacyanoferrates(II) and two-charge ions. A complete substitution of Co(II) or the formation the respective mononuclear hexacyanoferrate(II) M2[Fe(CN)2] was observed in neither of the studied systems Co(II) M(II). No Co(II) Mn(II) substitution was observed, even though the immobilized matrix was in contact with a solution for a long time.  相似文献   

10.
Reduction of V2O5/Al2O3 and V2O5/silica-alumina produced Lewis acid sites which could strongly adsorb CO (heat of adsorption: 90 kJ/mol). Such strong acid sites were not formed in the cases of V2O5/SiO2 and V2O5/MgO. V2O5 loaded on Al2O3 interacted with the basic sites of alumina but not with the acidic sites, while the V2O5 on silica-alumina interacted with the acidic sites of the silica-alumina and decreased its acidity.
V2O5/Al2O3 V2O5/SiO2–Al2O3 , CO ( 90 /). V2O5/SiO2 V2O5/MgO . V2O5, Al2O3, , , V2O5 SiO2–Al2O3 - .
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11.
Molecular isotope exchange of CO with14CO for Rh6(CO)16/Sn(II)–SiO2, Rh6(CO)16/Al2O3, Rh(I)(CO)2/Al2O3, Rh4(CO)12/Al2O3 carbonyl complexes of rhodium has been studied. Estimates of the activation energies and a mechanism of the CO exchange are suggested.
, (Rh6(CO)16/Sn(II)–SiO2, Rh6(CO)16/Al2O3, RhI(CO)2/Al2O3, Rh4(CO)12/Al2O3), 14CO. CO .
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12.
Zusammenfassung 1,3-Dimethyl-4,5-diaminouracil (DAL) hat sich als sehr empfindliches Reagens zum selektiven Nachweis von Co2+-Ionen im stark alkalischen Medium einer Phosphatpufferlösung (pH=11,20) erwiesen. Es wurden vier Additionsverbindungen von DAL mit den Zentralatomen Cd(II), Pd(II), Ni(II) und Co(II) im Verhältnis Me DAL=1 2 hergestellt. Spektrophotometrische Untersuchungen weisen darauf hin, daß bei pH 6 bis 7 eine Komplexverbindung im Verhältnis CoDAL=12 gebildet wird.
Summary 1,3-dimethyl-4,5-diaminouracil (DAL) has been found to be a very sensitive reagent for the selective detection of Co2+ ions in strong alkaline medium of a phosphate buffer solution (pH=11.20). Four addition compounds of DAL with the central atoms Cd(II), Pd(II), Ni(II) and Co(II) with the ratio MeDal=12 have been prepared. Spectrophotometric studies indicate that at pH=6–7, complex compound is produced with the ratio CoDAL=12.
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13.
Composition and catalytic properties in ethylene polymerization of supported systems prepared via the interaction of Ti(CH2C6H5)3X (X=F, Cl, Br) and Zr(CH2C6H5)2Cl2 complexes with silica and alumina have been studied. Halide addition to benzyl complexes decreases the polymer molecular mass.
, Ti(CH2C6H5)3X (X=F, Cl, Br) Zr(CH2C6H5)2Cl2 SiO2 Al2O3. , .
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14.
The principles of benzene hydrogenation have been studied with sulfide catalysts NI/MS2, Ni/SiO2, M/SiO2 and (Ni, M)/SiO2 (M=Mo, W) obtained via metal complex precursors or by impregnation. In bimetallic catalysts active sites of benzene hydrogenation are formed upon reduction of the active component for thiophene hydrogenolysis.
Ni/MS2, Ni/SiO2, M/SiO2, (Ni,M)/SiO2, M=Mo W, , . , .
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15.
A polarographic investigation of solutions containing trioxalate complexes of Co(III) reveals that the overall electrode process Co(III) Co(0) is accompanied by slow formation of ionic associates between aquacomplexes of Co(II) and trioxalate complexes of Co(III). Use of a relatively high concentration of oxalate ions (0.001 M) quells this association. Under these conditions, it is possible to divide the measured current into two constituents related to the primary electroreduction Co(III) Co(II) and the subsequent process Co(II) Co(0). The earlier data on the rate constant and apparent transfer coefficient for the process Co(II) Co(0) are used for calculating corrected Tafel plots for the electrode reaction Co(III) Co(II). The plots are practically linear and independent of the concentration of the supporting-electrolyte cation in a wide range of potential drops (1 V) across the dense layer. A theoretically expected parallel shift of the plots is observed in solutions with a variable concentration of discharging species. This observation and similar data obtained for a mixed potassium–sodium supporting electrolyte bear testimony to good agreement between the obtained results and the theory.  相似文献   

16.
Reduction of Pd/La2O3 catalysts by H2 and CO at room temperature leads to the formation of Pd+ ions stabilized in bulk and the subsurface layer. Hydrogen spillover seems to enhance the process. O 2 and (CO) 2 radicals are formed after adsorption of CO and O2 at 295 K.
Pd/La2O3 CO Pd+ . . CO O2 (CO) 2 O 2 La2O3.
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17.
Absorption spectra are reported for solutions containing Co(II) and ammonia. Spectra are calculated for five Co(II) aquoamino complexes. The spectra are used to determine Dq and B, parameters of the bonds in these compounds. It is found that Dq and B change nonlinearly and nonadditively. The parameters c, Dt, Ds, and have also been established for [Co(H2O)6]2+ and [Co(NH3)6]2+. The parameter variation can be explained if the H2O molecules form weaker bonds to the central atom than do the NH3 molecules, but are capable of d-p interaction.  相似文献   

18.
The influence of CaCl2 · Ca(OH)2 · H2O nuclei on the hydration of Ca3SiO4Cl2 was studied by means of calorimetry, X-ray diffraction, simultaneous DTA-TG and chemical analysis of the liquid phase.
Zusammenfassung Der Einfluss von CaCl2 · Ca(OH)2 · H2O-Zusätzen auf die Hydratation von Calciumchlorid-silicat Ca3SiO4Cl2 wurde durch Kalorimetrie, Röntgenbeugung, simultane TG-DTA und chemische Analyse der flüssigen Phase untersucht.

l3 · ()2 Ca3SiO4Cl2 , .
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19.
The reduction of BaSO4 by carbon was investigated by means of isothermal thermogravimetric measurements. In combination with a high-temperature thermobalance, solid electrolyte cells were used (i) to purify the N2 flow gas, and (ii) to measure the partial pressure of oxygen (COCO2 ratio, respectively) in the outlet gases.Mass loss curves and in the outlet gases were recorded at 743–955 °C. The activation energy of the process was calculated from the isothermal TG curves. X-ray diffraction and SEM showed that the solid product in the whole temperature interval comprised only cubic BaS.
Zusammenfassung Die Reduktion von BaSO4 mit Kohlenstoff wurde durch isotherme thermogravimetrische Messungen verfolgt. Mit einer Hochtemperatur-Thermowaage wurden Festelektrolyten kombiniert (1)zur Reinigung des Spülgases N2 von Sauerstoff, (2) zur Messung des O2-Partialdruckes (bzw. des Verhältnisses COCO2) im entweichenden Gas. Die Gewichtsverlust- und Sauerstoffpartialdruck-Kurven bei 743–955 °C wurden aufgezeichnet. Aus den TG-Kurven wurde die Aktivierungsenergie des Prozesses berechnet. Im gesamten untersuchten Temperaturbereich entstand als festes Reaktionsprodukt nach Röntgenbeugungs- und SEM-Untersuchungen nur kubisches B2S.

. , -, ( :2) . 743–955° — . . , .
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20.
The thermal decomposition of potassium chlorate was investigated as a function of doping and there seems to be a correlation between the polarizing nature of the dopant cation and the thermal degradation temperature of potassium chlorate. In particular, transition metal cations influence strongly the temperature of decomposition. Irradiation and mechanical shock defects influence also the process. A possible mechanism in terms of the semi-conductive properties of the defective chlorates is discussed.
Zusammenfassung Die thermische Zersetzung von Kaliumchlorat wurde in Abhängigkeit von der Zugabe von Zusätzen untersucht und es scheint eine Korrelation zwischen der polarisierenden Beschaffenheit des Additivkations und der thermischen Zersetzungstemperatur von Kaliumchlorat zu bestehen. Besonders die Übergangsmetallkationen beeinflussen die Zersetzungstemperatur stark. Bestrahlung und mechanische Stoßdefekte beeinflussen den Vorgang ebenfalls. Ein möglicher Mechanismus wird anhand der Halbleiter-Eigenschaften der defekten Chlorate erörtert.

Résumé On a étudié la décomposition thermique du chlorate de potassium en fonction de l'ajout d'additifs. Il semble qu'une corrélation existe entre la nature polarisante du cation de l'additif et la température de la dégradation thermique du chlorate de potassium. Enparticulier, ce sont les cations des métaux de transition, qui exercent une forte influence sur la température de décomposition. L'irradiation et des défauts causés par choc mécanique influencent aussi le processus. On discute un mécanisme possible à partir des propriétés semi-conductrices des chlorates présentant des défauts.

. . , , . .
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