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1.
Summary New complex salts of lanthanide thiocyanates with hexamethylenetetramine of the general formulaLn(NCS)3·2[N4(CH2)6·nH2O, whereLn=La,Pr,Nd,Sm,Gd,Dy,Er andn=0–10, have been analyzed. IR spectra have been obtained in the range of 200–4000 cm–1, frequencies of vibrations of low and high hydration state compounds have been analyzed, and differences between the structures of the coordination speheres of these salts are demonstrated. Diffractometric examinations and measurements of the magnetic susceptibility of several salts have been performed.
Synthese und spektroskopische, diffraktometrische und magnetische Untersuchungen von Verbindungen der Lanthaniden mit Rhodanid und Hexamethylentetramin
Zusammenfassung Neue Komplexsalze der Lanthaniden mit Rhodanid und Hexamethylentetramin mit der allgemeinen FormelLn(NCS)3·2[N4(CH2)6nH2O (Ln=La,Pr,Nd,Sm,Gd,Dy,Er;n=0–10) wurden untersucht. Die IR-Spektren der Verbindungen im Bereich von 200–4000 cm–1 wurden aufgenommen. Die Schwingungsfrequenzen hoch- und niederhydrierter Verbindungen wurden analysiert und die Unterschiede in der Struktur der Koordinationssphäre bestimmt. An einigen Komplexen wurden diffraktometrische Untersuchungen und Messungen der magnetischen Suzaptibilität durchgeführt.
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2.
Liquid-liquid extraction of Th(IV) and U(VI) has been investigated by commercial extractant PC-88A in toluene. The optimum conditions for extraction of these metals have been established by studying the various parameters like acid concentration/pH, reagent concentration, diluents and shaking time. The extraction of Th(IV) was found to be quantitative with 0.1–1.0M HNO3 acid and in the pH range 1.0–4.0 while U(VI) was completely extracted in the pH range 1.0–3.5 with 2.5·10–2M and 2.·10–2M PC-88A in toluene, respectively. The probable extracted species have been ascertained by log D-log C plot as ThR4·4HR and UO2R2·2HR, respectively. The method permits separation of Th(IV) and U(VI) from associated metals with a recovery of 99.0%.  相似文献   

3.
The water-vapor pressure has been measured by a static method, the temperature limits for existence have been determined, and the parameters of the equation lgp [Torr]=ba/T have been calculated for the following crystal hydrates: Mn(ClO4)2 · 2H2O (90–130°C, a=3527.0,b=8.487), Ni(ClO4)2 · 4H2O (60–100°C,a=3606.7,b=9.704), Ni(C1O4)2 · 2H2O (110–160°C,a = 4261.7,b = 10.103), Cd(ClO4)2 · 6H2O (25–58.2°C,a = 3143.7,b = 9.356), Cd(ClO4)2 · 2H2O (90–144.8°C,a=3823.3,b = 9.472), Pb(ClO4)2 · 3H2O (10–47°C,a = 2932.9,b = 9.391 and 47–81.5°C,a = 2448.1,b=7.877), Pb(ClO4)2 · H2O (60–102.4°C,a=3610.2,b = 9.857). A hitherto unknown metastable hydrate Cd(ClO4)2 · 4H2O with a phase transition at 30.9°C (20–30.9°C,a = 3669.5,b = 11.343 and 30.9–63.7°C,a=3058.6,b = 9.339) has been detected.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 466–470, March, 1993.  相似文献   

4.
The sorption of hafnium on hydrous titanium oxide (TiO2·1.94 H2O) has been studied in detail. Maximum sorption of hafnium can be achieved from a pH 7 buffer solution containing boric acid and sodium hydroxide using 50 mg of the oxide after 30 minutes shaking. The value ofk d, the rate constant of intraparticle transport for hafnium sorption, from 0.01M hydrochloric and perchloric acid and pH 7 buffer solutions has been found to be 17 mmole·g–1·min–2. The kinetics of hafnium sorption follows Lagergren equation in 0.01M HCl solution only. The values of the overall rate constantK=6.33·10–2 min–1 and of the rate constant for sorptionk 1=6.32·10–2 min–1 and desorptionk 2=2.28·10–5 min–1 have been evaluated using linear regression analysis. The value of correlation factor() is 0.9824. The influence of hafnium concentration on its sorption has been examined from 4.55·10–5 to 9.01·10–4 M from pH 7 buffer solution. The sorption data followed only the Langmuir sorption isotherm. The saturation capacity of 9.52 mmole·g–1 and of a constant related to sorption energy have been estimated to be 2917 dm3·mole–1. Among all the additional anions and cations tested only citrate ions reduce the sorption significantly. Under optimal experimental conditions selected for hafnium sorption, As(III), Sn(V), Co(II), Se(IV) and Eu(III) have shown higher sorption whereas Mn(II), Ag(I) and Sc(III) are sorbed to a lesser extent. It can be concluded that a titanium oxide bed can be used for the preconcentration and removal of hafnium and other metal ions showing higher sorption from their very dilute solutions. The oxide can also be employed for the decontamination of radioactive liquid waste and for pollution abatement studies.  相似文献   

5.
It is shown by pulse radiolysis that in aqueous solutions of hydrazine containing oxygen the radical N2H3 reduces oxygen to O2 at pH > 7 (k 3·109 dm3· mole–1·sec–1), while this reaction does not occur for the protonated form N2H4 + at pH < 7 (k, 5·106 dm3·mole–1·sec–1). The rate constants for the disappearance of O2 have been determined in the pH range from 4 to 12. Rate constants have been calculated for the reaction of O with N2H4 [k=(1.6 ±0.2)·109 dm3·mole–1·sec–1] and of O3with N2H4 [k=(1.2 ±0.2)·106 dm3· mole–1·sec–1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 341–345, February, 1991.  相似文献   

6.
Characteristics of the ion pairs HCOO·Na+·H2O, HCOO·K+·H2O, and also Na+·H2O and K+·H2O were calculated by the nonempirical Hartree—Fock—Roothan linear-combination-of-atomic-orbitals self-consistent-field (SCF) molecular-orbital method in a two-exponent Dunning basis using an extended set of Huzinaga—Dunning Gaussian functions. The basis was supplemented by polarization functions ofd type for the oxygen atom andp type for the H atom and also by diffusion functions ofp type for the oxygen atom. Characteristics of the ion pairs HCOO·Li+ and HCOO·Na+ were calculated taking into account the electronic correlation according to the Möller — Plesset second-order perturbation theory. Significant quantitative difference was observed in the hydration of ionogens and free cations. The stability of the ionogens HCOOMe in aqueous solutions, increasing from Li+ to Cs+, is not explained by the difference between the energies of complexation and the energies of hydration of the cations. The better solubility of the salt molecule with a cation of smaller radius is due to the higher degree of hydration of that ionogen.N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 117977 Moscow. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 12, pp. 2700–2707, December, 1992.  相似文献   

7.
Three new compounds have been synthesized: [Mg(4-MePy)4(NCS)2]·0.67(4-MePy)·xH2O (x=0.07–0.24 [Mg(4-MePy)4(NCS)2]·(4-MePy) and [MgPy4(NCS)2]·2Py·2H2O. Their structures have been investigated by Raman spectroscopy and the first two compounds have been shown to be isostructural with the clathrates [Cu(4-MePy)4(NCS)2]·0.67(4-MePy)·0.33H2O and [Ni(4-MePy)4(NCS)2]·(4-MePy). Thermal and other properties have been studied. It was concluded from an analysis of the literature that pyridine complexes of Mg and Ca are capable of forming clathrates with Py as guest molecule, although these compounds have not been examined before from the point of view of clathrate chemistry.Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 34, No. 2, pp. 66–73, March–April, 1993.  相似文献   

8.
A series of square-planar nickel(II) hexamethylenedithiocarbamate complexes with heterogeneous coordination spheres of composition [NiX(hmidtc)Y] · nCHCl3 [X = Cl, Br, I or NCS; hmi = C6H12, dtc = S2CN; Y = PPh3 or PBu3, n = 0,1] have been synthesized and characterized by elemental analyses, i.r. and u.v.–v.i.s. spectroscopy, magnetochemical and conductivity measurements, and by thermal analysis. X-ray structures of [NiCl(hmidtc)(PPh3)] · CHCl3 and [NiBr(hmidtc)(PPh3)] · CHCl3 have been determined.  相似文献   

9.
Reactions of carbonate radical (CO3 ), generated by photolysis or by radiolysis of a carbonate solution with nickel(II)-iminodiacetate (Ni(II)IDA) were studied at pH 10.5 and ionic strength (I)==0.2 mol·dm–3. The stable product arising from the ligand degradation in the complex is mainly glyxalic acid. Time-resolved spectroscopy and transient kinetics were studied using flash photolysis. From the kinetic data it was suggested that the carbonate radical initially reacts with Ni(III)IDA with a rate constant (2.4±0.4)·106 dm3·mol–1·s–1 to form a Ni(II)IDA species which, however, undergoes a first-order transformation (k=2.7·102·s–1) to give a radical intermediate of the type Ni(II)RNHCHCO 2 ) which rapidly forms an adduct containing a Ni–C bond. This adduct decays very slowly to give rise to glyoxalic acid. From a consideration of equilibrium between Ni(II)IDA and Ni(III)IDA, the one electron reduction potential for the Ni(III)IDA/Ni(II)IDA couple was determined to be 1.467 V.  相似文献   

10.
The complex compounds [Co(DH)2(Anil)2][BF4] and [Co(DH)2(Py)2][BF4] were synthesized from Co(BF4)2 · 6H2O–DH2–A–alcohol–water systems (DH2 is dimethylglyoxim and A is pyridine (Py) or aniline (Anil)), and their crystal structures were determined using X-ray diffraction analysis. In octahedral Co(III) complexes, two dimethylglyoxime radicals lie in the equatorial plane and are joined via the intramolecular hydrogen bond O–H···O. The complexes with pyridine and aniline have similar configurations but different crystal structures.  相似文献   

11.
A double clathrate hydrate with the composition THF·0.5(n-Pr)4NF·16H2O and cubic structure II (CS-II,a=17.67 Å) has been obtained. Its experimental density is 1.053±0.001 g/cm3; its melting point is 8.1°C, i.e. 3.1°C higher than that of the THF·17H2O hydrate. The double hydrates of acetone, 1,4-dioxan, trimethyleneoxide and 1,3-dioxolane with (n-Pr)4NF have melting points of –14.8, –5.5, –2.6 and –9.6°C, respectively. With pressure increase up to 6 kbar the melting points of the double hydrates increase monotonously in contrast to common CS-II hydrates. The friability of the structure of the hydrates (the packing coefficient) and their sensitivity to pressure (dT/dP) are compared.The results of this work have been reported at the International Seminar on Inclusion Compounds, Jaszowiec (Poland), 24–26th September 1987.  相似文献   

12.
Characteristics of the -induced chain reaction between sulfur dioxide and molecular oxygen in perchloric and sulfuric acid media in the presence of Ce(III) ions have been studied. The concentration effects of dissolved oxygen (0.2·10–3–9.4·10–3 mol/dm3, sulfur dioxide (0.3·10–1–2.0·10–1 mol/dm3 and Ce(III) (0.2·10–3–4.8·10–3 mol/dm3) and dose rate (0.26·1019–1.0·1019 eV/dm3·s) on the radiation — chemical yield of oxygen consumption G(–O2) and accumulation of sulfate G(HSO 4 ), have been investigated. The reaction proceeds with G(–O2) reaching 102–103 molecule/100eV in a catalytic regime. The reaction rate in perchloric acid medium is 3–4 times lower than that in the sulfuric acid medium and depends on the SO2, O2 and Ce(III) concentrations, the reaction order varying from 1.0 to 0 and/or in the reverse direction. The mechanism of the process involves chain propagation with 3 stages and 3 intermediates: SO3H, HSO5 and Ce(IV). The catalytic effect is caused by the interaction of HSO4 with Ce(IV) ions followed by their reduction when interacting with SO2, yielding SO3H radicals. Chain termination may be due to one or two of the three intermediates or due to all three particles, the kinetics depending on this. Kinetic equations describing the experimental data have been obtained.  相似文献   

13.
Zusammenfassung Das Verteilungsverhalten der Halogenide und Halogenometallate von Gallium, Indium und Thallium mit den drei Solventien (S) Tributylphosphat (TBP), Cyclohexanon (Cyclo) und Isobutylmethylketon (IBMK) wurde untersucht. Die extrahierten Verbindungen wurden nach der Geradenmethode nach Asmus, der logarithmischen Methode nach McKay, der Methode der kontinuierlichen Variation, durch Analyse der beiden Phasen und durch konduktometrische Extraktionstitration nachgewiesen. Identifiziert wurden folgende Verbindungen: [GaCl4]·2 S, Ga-(SCN) 3·3 TBP, [Ga(SCN)4]·2 TBP, [InCl4]·2 TBP, [InBr4]·2TBP, [InBr4x Cyclo, [InBr4]·x IBMK, [InJ4]·2 S, In(SCN)3·3 TBP, [In(SCN)4]·2 TBP, TlCl3·1 TBP, [TlCl4]·2 S, TlBr3·1 TBP, [Tl-Br4] ·2 S, TlJ3·x TBP und [TlJ4]·xS. Wegen der nicht eindeutig definierten Oxydationsstufe von Thalliumjodiden ergaben sich bei den Versuchen experimentelle Schwierigkeiten. Daher wurde in diesem System zusätzlich das radioaktive Isotop 204Thallium verwendet.
Extracted compounds of gallium, indium and thallium in distribution systems with tributyl phosphate, cyclohexanone and isobutylmethylketone
The behaviour of distribution of the halides and halogenometallates of gallium, indium and thallium with the three solvents (S) tributylphosphate (TBP), cyclohexanone (Cyclo) and isobutylmethylketone (IBMK) are investigated. The extracted compounds are detected with the straight-line method of Asmus, the logarithmic method of McKay, the method of continuous variation, by analysis of the two phases, and with the conductometric extraction-titration. The following compounds were identified: [GaCl4]·2S, Ga(SCN)3·3TBP, [Ga(SCN)4]·2TBP, [InCl4]·2TBP, [InBr4]·2TBP, [InBr4x Cyclo, [InBr4]·x IBMK, [InJ4] ·2S, In(SCN)3·3TBP, [In(SCN)4]·2TBP, TlCl3·1TBP, [TlCl4]·2S, TlBr3 ·1TBP, [TlBr4]·2S, TlJ3·x TBP and [TlJ4]·x S. The not unequivocally defined stage of oxidation of thallium iodides resulted in experimental difficulties. Thus, in this system the radioactive isotope 204thallium was additionally used.


Herrn Professor Dr. E. Asmus zum 60. Geburtstag gewidmet.

Wie danken Herrn Priv.-Doz. Dr. H. Nickel für die freundliche Unterstützung bei den in der KFA Jülich durchgeführten radioaktiven Messungen.  相似文献   

14.
Geometric, electronic, and energy characteristics of the complexes formed in the CF4 ·nAIF3 (n = I or 2) and CBr4 ·nAIBr3 (n = 1, 2, or 4) systems have been determined by the semiempirical AM I method. Besides the donor-acceptor complexes, the CBr3 +...AIBr4 , CBr3 +...Al2Br7 , CBr22+...(AlBr4 )2, and CBr2 2+...(Al2Br7 )2 ionic complexes can be formed in the CBr4 ·nAlBr3 systems. In the cations and dications of polyhalomethanes (when Hal = Cl, Br, or l) in both the free and bound (included in ionic complexes) states, carbon atoms carry negative charges, the C-Hal bonds are substantially shortened, and the positive charges are located on one-coordinate halogen atoms. These cations and dications can be considered as halenium ions that differ from halenium salts with dicoordinate halogen atoms. In the cationic and dicationic complexes of the CBr4 ·nAlBr3 systems, the maximum positive charges on the Br atoms are 0.39 and 0.94, respectively. Fluorine-containing cations and dications have structures similar to those of carbenium ions, whereas in the CF4 ·nAIF3 systems (n = l or 2), only donor-acceptor complexes are formed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya. No. 3, pp. 554–560, March, 1996.  相似文献   

15.
The role of nitrate ions in uranyl ions transport across TBP-kerosene oil supported liquid membranes (SLM) at varied concentrations of HNO3 and NaNO3 has been studied. It has been found that nitrate ions move faster compared to uranyl ions at the uranium feed solution concentrations studied. The nitrate to uranyl ions flux ratio vary from 355 to 2636 under different chemical conditions. At low uranium concentration the nitrate ions transport as HNO3 · TBP, in addition to as UO2(NO3)2 · 2TBP type complex species. The flux of nitrate ions is of the order of 12.10 · 10–3 mol · m–2 · s–1 compared to that of uranium ions (4.56 · 10–6 mol · m–2 · s–1). The permeability coefficient of the membrane for nitrate ions varies with chemical composition of the feed solution and is in the order of 2.5 · 10–10 m–2 · s–1. The data is useful to estimate the nitrate ions required to move a given amount of uranyl ions across such an SLM and in simple solvent extraction.  相似文献   

16.
Summary New complex salts of lanthanide chlorides with hexamethylenetramine of the general formulaLnCl3·2HMTA·nH2O [Ln=La, Pr, Nd, Sm, Dy, Er;HMTA-hexamethylenetetramine N4(CH2)6;n=8, 10, 12] have been obtained. On the basis of IR IR spectra (4000-200cm–1) and Raman spectra (3000-300 cm–1), changes in the coordination sphere structure of the salts occurring in the course of thermal dehydration have been determined.
Darstellung und Untersuchung der Eigenschaften von Komplexsalzen der Lanthanidchloride mit Hexamethylentetramin
Zusammenfassung Neue Komplexsalze der Lanthanidchloride mit Hexamethylentetramin mit der allgemeinen FormelLnCl3·2HMTA·nH2O [Ln=La, Pr, Nd, Sm, Dy, Er;HMTA — Hexamethylentetramin N4(CH2)6;n=8, 10, 12] wurden dargestellt. Die Änderungen in der Struktur der Koordinationssphäre während der thermischen Dehydration der Salze wurden mittels Infrarot-(4 000–200 cm–1) und Ramanspektroskopie (3 000–300 cm) bestimmt.
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17.
The novel zeolite CF-3, with a high ratio of SiO2/Al2O3 and a characteristic X-ray powder diffraction pattern, has been synthesized hydrothermally from a TMEDA-Na2O–SiO2–Al2O3–H2O system at 200°C. The molar composition of CF-3 is (0.4–0.6)Na2O·(1.5–6.3)TMEDA·Al2O3·(80–400)SiO2·(0–17)H2O·CF-3 is similar to ZSM-39 and melanophlogite, which have a clathrate-type structure.  相似文献   

18.
The sorption of Fe(III) at low pH range from 1 to 4.5 on open cell polyether type HTTA-loaded polyurethane foam has been carried out using batch technique. The optimum shaking time for 2.5· 10–4M solution of Fe(III) was found to be 30 minutes. The concept of macropore and micropore nature of polyurethane foam sorbent offers unique advantages of adsorption. Freundlich and Langmuir adsorption isotherms are followed at low concentration range from 1·10–4 to 3·10–4M solution of Fe(III). The Freundlich constant (1/n=0.46±0.013 andK=9.16±1.39 mg·g–1) and Langmuir isotherm constants(M=21.78 mg·g–1 andb=88.41±9.731·g–1) were established. The sorption mean free energyE=12.22±0.09 kJ·mol–1 and loading capacityC m =145.21±6.1 mg·g–1 were evaluated using Dubinin-Radushkevich isotherm, which suggested that the adsorption mechanism was chemisorption.  相似文献   

19.
Orthoperiodic and orthotelluric acids, their salts MIO6H4 (M = Li, Rb, Cs) and CsH5TeO6, and dimers of the salt · acid type are calculated within density functional theory B3LYP and basis set LanL2DZ complemented by the polarizationd,p-functions. According to calculations, the salt · acid dimerization is energetically favorable for compounds MIO6H4 · H5IO6 (M = Rb, Cs) and CsIO6H4 · H6TeO6. The dimerization energy is equal to 138–146 kJ mol–1. With relatively small activation energies equal to 4 kJ mol–1 (M = Li) and 11 kJ mol–1 (M = Rb, Cs), possible is rotation of octahedron IO6 relative to the M atom in monomers of salt molecules. The proton transfer along an octahedron occurs with activation energies of 63–84 kJ mol–1. The activation energy for the proton transfer between neighboring octahedrons of the type salt · acid acid · salt equals 8–17 kJ mol–1. Quantum-chemical calculations nicely conform to x-ray diffraction and electrochemical data.  相似文献   

20.
2-[2-(Hydroxybenzylidene)-amino]-2-hydoxymethylpropane-1,3-diol (HL) reacts with cobalt, nickel, copper and zinc chlorides, bromides and acetates in water–ethanol solutions and gives MLX · nH2O and ML2 · nH2O complexes (M = Co, Ni, Cu, Zn; X = Cl, Br; n = 0–5). Single crystals of CuLBr were grown, and its crystal structure was determined by X-ray diffraction analysis. The crystals are tetragonal, a = 17.024(2), c = 8.720(2) Å, space group P 21 c, Z = 8, R 1 = 0.0349. In the structure of this complex, the copper atom coordinates the deprotonated HL molecule. The coordination polyhedron of the central atom is an elongated tetragonal pyramid. Its base is built of the imine nitrogen atom, phenolic and alcoholic oxygen atoms, and bromine atom. The apex of the pyramid is occupied by the bromine atom of the adjacent complex connected with the initial complex by the plane of sliding reflection. Thus, the crystal contains infinite chains of complexes running along the c axis, the complexes being united by both bridging bromine atoms and O–H···O hydrogen bonds. The conclusions on the compositions and structures of the remaining compounds were made on the basis of elemental and combined thermal analyses, IR spectroscopy, and magnetic chemistry data. The copper halide complexes were found to have dimeric, and the other metal complexes monomeric, structures. In the synthesized complexes, the azomethine HL can function as a bidentate or tridentate ligand. The thermolysis of the coordination compounds proceeds through the stages of elimination of crystal water molecules (75–90°C) or inner-sphere water molecules (145–155°C) and complete thermal destruction (485–550°C).  相似文献   

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