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1.
The macrocycle-mediated fluxes of alkali, alkaline earth, and several transition metal cations have been determined and compared in a H2O-CH2Cl2-H2O liquid membrane system using four water-insoluble macrocycles containing a dialkylhydrogenphosphate moiety. Transport of alkali metal cations by these ligands was greatest from a source phase pH = 12 or above into an acid receiving phase (pH = 1.5). Very low fluxes were observed for the transport of the alkaline earth cations and all transition metal ions studied except Ag+ and Pb2+ which were transported reasonably well by these new macrocycles.Deceased: September 5, 1987.  相似文献   

2.
Extraction capability and selectivity of acetyl-containing phosphine oxides R2P(O)CMe2CH2C(O)Me (R = Pr, Bu, n-C5H11, n-C6H13, n-C8H17, Ph) toward actinides (UVI, ThIV) and trivalent lanthanides (LaIII, NdIII, HoIII, YbIII) were studied. The new ligands were shown to be more efficient and selective in the extraction of uranium, thorium, and heavy lanthanides from nitric acid solutions into chloroform as compared to the known extractants such as carbamoylphosphine oxide Ph2P(O)CH2C(O)NBu2, trioctylphosphine oxide (n-C8H17)3P(O), and tributyl phosphate (n-BuO)3P(O).  相似文献   

3.
Macrocyclic polyethers transport alkali and alkaline earth, but not trivalent lanthanide cations in H2OCHCl3H2O liquid membrane systems. We report here the use of 18-crown-6 to transport europium after first reducing it to the bivalent oxidation state. In this oxidation state, the Eu(NO3)2 flux is comparable to that of Sr(NO3)2.  相似文献   

4.
Investigation of Cocrystallization in the Systems Mn(OOCCH3)2-Co(OOCCH3)2-H2O, Mn(OOCCH3)2-Ni(OOCCH3)2-H2O, Mn(OOCCH3)2-Zn(OOCCH3)2-H2O at 60°C The three-component systems Mn(OOCCH3)2-Co(OOCCH3)2-H2O, Mn(OOCCH3)2-Ni(OOCCH3)2-H2O and Mn(OOCCH3)2-Zn(OOCCH3)2-H2O at 60°C were investigated by physio-chemical analysis. There is an interruption in the series of mixed crystals formed in the three-component systems. The inclusion of Co2+- and Ni2+ in Mn(OOCCH3)2 · 2 H2O of Mn2+ in Co(OOCCH3)2 · 2 H2O, Zn(OOCCH3)2 · 2 H2O and Ni(OOCCH3)2 · 4 H2O is based on isodimorphic substitution. It was found that in the system Mn(OOCCH3)2-Zn(OOCCH3)2-H2O crystallizes Zn(OOCCH3)2 · Mn(OOCCH3)2 · 2 H2O. It was identified by the X-ray and differential thermal analysis.  相似文献   

5.
Three novel Cd(II) coordination polymers, namely, [Cd(Dpq)(1,8-NDC)(H2O)2][Cd(Dpq)(1,8-NDC)]·2H2O (1), [Cd(Dpq)(1,4-NDC)(H2O)] (2), and [Cd(Dpq)(2,6-NDC)] (3) have been obtained from hydrothermal reactions of cadmium(II) nitrate with the mixed ligands dipyrido [3,2-d:2′,3′-f]quinoxaline (Dpq) and three structurally related naphthalene-dicarboxylate ligands [1,8-naphthalene-dicarboxylic acid (1,8-H2NDC), 1,4-naphthalene-dicarboxylic acid (1,4-H2NDC), and 2,6-naphthalene-dicarboxylic acid (2,6-H2NDC)]. Single-crystal X-ray diffraction analysis reveals that the three polymers exhibit novel structures due to different naphthalene-dicarboxylic acid. Compound 1 is a novel cocrystal of left- and right-handed helical chains and binuclear complexes and ultimately packed into a 3D supramolecular structure through hydrogen bonds and π-π stacking interactions. Compound 2 shows a 2D rectangular network (4,4) bridged by 1,4-NDC with two kinds of coordination modes and ultimately packed into a 3D supramolecular structure through inter-layer π-π stacking interactions. Compound 3 is a new 3D coordination polymer with distorted PtS-type network. In addition, the title compounds exhibit blue/green emission in solid state at room temperature.  相似文献   

6.
AlF3 is a strong Lewis acid and several hydrates of it are known, namely the monohydrate, the trihydrate (of which two polymorphs have been described) and the nonohydrate, which forms in the abundance of water, as well as a more complex fluoride of composition Al0.820.18F2.46(H2O)0.54 whose structure has been related to the ReO3 type. The monohydrate features edge connected [AlF6] octahedra, in the tri- and nonahydrate mixed F/O coordination of aluminum is observed. Here we report on a new aluminium fluoride hydrate, AlF3·6H2O, which could be obtained via ionothermal synthesis in the ionic liquid n-hexyl-pyridinium tetrafluoroborate. The ionic liquid serves in the synthesis of AlF3·6H2O as the reaction partner (fluoride source) and solvent. Overmore it controls the water activity allowing access to the missing AlF3·6H2O. Single-crystal X-ray diffraction analysis of AlF3·6H2O shows that it crystallizes in the anti-Li3Bi-type of structure according to F3[Al(H2O)6] (Fm-3m, a = 893.1(2) pm, Z = 4) featuring hexaaqua aluminium(III) cations and isolated fluoride anions. The compound was further characterized by powder X-ray diffraction, TG/DTA, IR analyses.  相似文献   

7.
Summary The paper presents data on the solubility of La, Ce, Pr, Nd sulfates in the polycomponent system La2(SO4)3·8H2O-Ce2(SO4)3·8H2O-Pr2(SO4)3·8H2O-Nd2(SO4)3· 8H2O-H2SO4-H2O (at 25°C and 64°C) as well as in the same polycomponent system but in the presence of CaSO4·2H2O. The solubility of the sulfates — ocathydrates of Pr at 25°C and 64°C and of La and Ce at 64°C in tricomponent systemLn 2(SO4)3·8H2O-H2SO4-H2O are also reported.
Löslichkeit einiger Lanthanidsulfate in Mehrkomponenten-Systemen mit H2SO4
Zusammenfassung Die Arbeit präsentiert Daten für die Löslichkeit von La-, Ce-, Pr- und Nd-Sulfaten in den Vielkomponenten-Systemen La2(SO4)3·8H2O-Ce2(SO4)3·8H2O-Pr2(SO4)3·8H2O-Nd2(SO4)3· 8H2O-H2SO4-H2O (bei 25°C und 64°C) sowie in den gleichen Systemen, jedoch in Anwesenheit von CaSO4·2H2O. Über die Löslichkeit von Sulfatoctahydraten von Pr bei 25°C und 64°C und von La und Ce bei 64°C in den Dreikomponenten-SystemenLn 2(SO4)3·8H2O-H2SO4-H2O wird auch berichtet.
  相似文献   

8.
An uncompleted reaction between equimolar amounts of Co2CO3(OH)2·2H2O and trans-1,4-H4cyclohexanediaminotetraacetic acid in water affords the ‘acid’ complex {[CoII(trans-1,4-H2CDTA)(H2O)4]·6H2O}n (1). Its IR spectrum does not show the expected ν(CO) band of carboxylic groups. Reactions in aqueous solution between Na(trans-1,4-H3CDTA) and Zn(AcO)2·2H2O or Na2(trans-1,4-H2CDTA) and Zn(NO3)2·6H2O yield {[Zn(trans-1,4-H2CDTA)(H2O)4]·6H2O}n (2) and {[Zn2(trans-1,4-CDTA)(H2O)2]·H2O}n (3) respectively. Crystal structures of compounds 1-3 and that of the trans-1,4-H4CDTA·2H2O acid are reported. For steric reasons, in the four reported structures the 1,4-CDTA ligand has the two iminodiacetate moieties as equatorial groups in the 1,4-cyclohexanedi-yl chair. Compounds 1 and 2 are isotype 1D polymers constructed by square planar MII(H2O)42+ knots (MII = CoII or ZnII) linked to bis-zwitterionic trans-1,4-H2CDTA2− ligands that play a typical μ2-O,O′-dicarboxylate bridging role. These 1D polymeric structures seem to be favoured by the H-bonded intra-stabilization of the bis-zwitterionic trans-1,4-H2CDTA2− ligand. In the neutral complex (3), the trans-1,4-CDTA acts as a bridging bis-chelating ligand as well as a syn-anti carboxylate building a polymer where the zinc(II) centres exhibit a rough bipyramidal trigonal coordination.  相似文献   

9.
The reactions of trivalent lanthanides and actinides with molten boric acid in high chloride concentrations result in the formation of M4[B16O26(OH)4(H2O)3Cl4] (M=Sm, Eu, Gd, Pu, Am, Cm, Cf). This cubic structure type is remarkably complex and displays both chirality and polarity. The polymeric borate network forms helical features that are linked via two different types of nine‐coordinate f‐element environments. The f–f transitions are unusually intense and result in dark coloration of these compounds with actinides.  相似文献   

10.
Conclusions The new molecular compound NH4F·H2O2 was observed during an investigation of the fusibility of the NH4F-H2O2-H2O system and has been isolated.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1617–1618, July, 1968.  相似文献   

11.
The structural characterization of tetranuclear cage-type cadmium(II) carboxylate [Cd4(2-cpida)2(2,2′-bpy)6]·(2,2-bpy)·(ClO4)·3H2O (1) (2-H3cpida = N-(2-carboxyphenyl)iminodiacetic acid, 2,2′-bpy = 2,2′-bipyridine) is described. H-bonding interactions between three lattice water molecules form a V-shaped trimer (H2O)3, which is stabilized by 1. In addition, luminescence investigations revealed that 1 shows enhanced emissions as compared with free 2-H3cpida in the liquid state.  相似文献   

12.
A new series of isostructural MOF-type carboxylates called MIL-116 (M2(OH)2[C12O12H2]·2H2O), was synthesized from the combination of mellitic acid and trivalent p cations M = Al3+, Ga3+ or In3+. Their structures were analyzed either by single-crystal microdiffraction using the synchrotron radiation beamline (ID13 station at ESRF, Grenoble) or solved from powder X-ray diffraction. The 3D hybrid framework is built up from the connection of infinite straight chains of metal-centered octahedra sharing trans corners linked to each other through the mellitate ligands. Here the ligand acts as octadentate linker with four of the carboxylic groups involved in the M–O–C bondings. The two other carboxylate arms remain non-bonded under their protonated form. This represents a rare case of the occurrence of both non-bonding and bonding organic functionalities in a MOF-type solid. Within the tunnels are located water species that interact with the non-coordinated –COOH groups pointing towards the channel.  相似文献   

13.
Solid-liquid equilibrium of ternary system Cd2+, Na+//Cl?-H2O at 298 K were studied by an isothermal solution saturation method. Experimental results indicate that there are three univariant curves AE, EF, and FB, two invariant points E, F, and three crystallization fields in the ternary system. The ternary system has one double salt Na2CdCl4 · 3H2O. The crystallization zones of equilibrium solid phases are CdCl2 · H2O (AEG field), Na2CdCl4 · 3H2O (EFM field), and NaCl (FBN field), respectively. The composition of the invariant point E is CdCl2 · H2O and Na2CdCl4 · 3H2O of which content was 52.70 and 4.11%, respectively. The composition of the invariant point F is Na2CdCl4 · 3H2O and NaCl of which content was 27.92 and 14.95%, respectively. The density of solution in the ternary system show regular changes along with the increased cadmium concentration. The results indicated that CdCl2 · H2O possessed the highest solubility among those three salts, which means a strong transfer of Cd ion and a high pollution risk of soil environment. And the solubility of NaCl would be restrained as the three salts existing together.  相似文献   

14.
Multicomponent heterocyclization of aliphatic amides with H2S and CH2O (1:3:2) in water-organic solvent mixture in the presence of BuONa led to the formation of 1,3,5-dithiazinane in high yield (30–95%) and with high selectivity (100%). Under these conditions benzamide gave 3,5-dibenzoyl-1,3,5-thiadiazinane in 74% yield, whereas due to ortho-effect the acetylsalicylamide with H2S and CH2O in a system BuOH-H2O without BuONa formed N-acetylsalicyloyl-1,3,5-dithiazinane (80%). Heterocyclization of α-aminosuccinic acid monoamide depending on the H2S and CH2O concentration occurred either at one or both NH2 yielding respectively mono-or bisdithiazinanes.  相似文献   

15.
Crystal Structure of (NMe4)2[Re3Br11(H2O)] [Re3Br9(H2O)3](H2O)2 . (NMe4)2[Re3Br11(H2O)] [Re3Br9(H2O)3](H2O)2 crystallizes from hydrobromic acid solution of Re3Br9 · 2 H2O and NMe4Br at 0 – 5°C. The crystal structure (monoclinic; P21/m (Nr. 11); a = 967.9(3); b = 1 529.7(4); c = 1 710.9(4) pm; β = 91.66(2)°; Z = 2; R = 0.113; Rw = 0.068) has been determined from four-circle diffractometer data. The structure contains two different cluster units of trivalent rhenium, isolated anionic [Re3Br11(H2O)]2? units and neutral cluster units that are connected through crystal water molecules to chains{[Re3Br9(H2O)3](H2O)2}.  相似文献   

16.
Conclusions A physicochemical investigation of the system Rb2CO3-H2O2-H2O in the region of high hydrogen peroxide concentrations at low temperatures revealed for the first time the formation of a peroxyhydrate with a high hydrogen peroxide content, of the composition Rb2CO3 · 6H2O2.  相似文献   

17.
The phase formation in the system ZrO(NO3)2-H3PO4-CsF(HF)-H2O was studied at the molar ratio CsF/Zr = 1 along the sections PO 4 3? /Zr = 0.5 and 1.5 at a ZrO2 concentration in the initial solution of 2?C14 wt %. The following compounds were isolated: Cs5Zr4F21 · 3H2O, CsZr2(PO4)3 · 2HF · 2H2O, CsZrF2PO4 · H2O, CsZr2F6PO4 · 4H2O (for the first time), CsHZrF3PO4 (for the first time), Cs0.70ZrF(PO4)1.23 · nH2O, and CsHZr2F2(PO4)2.66 · nH2O. The compositions of CsZrF2PO4 · H2O, Cs0.70ZrF(PO4)1.23 · nH2O, and CsHZr2F2(PO4)2.66 · nH2O are conditional. All the compounds were characterized by crystal-optical, X-ray powder diffraction, thermal analyses, and IR spectroscopy. The formula CsHZrF3PO4 was established by energy-dispersive analysis with a LEO-1450 scanning electron microscope and an MS-46 CAMECA X-ray microanalyzer.  相似文献   

18.
The interaction between trivalent lanthanide ions and poly(1,4,7,10,13‐pentaoxacyclopentadecan‐2‐yl‐methyl methacrylate), PCR5, in aqueous solution and in the solid state have been studied. In aqueous solution, evidence of a weak interaction between the lanthanides and PCR5 comes from the small red shift of the Ce(III) emission spectra and the slight broadening of the Gd(III) EPR spectra. From the Tb(III) lifetimes in the presence of H2O and D2O the loss of one or two water coordinated molecules is confirmed when Tb(III) is bound to PCR5. An association constant of the order of 200 M?1 was obtained for a 1:1 (lanthanide:15‐crown‐5) complex from the shift of the polymer NMR signals induced by Tb(III). A similar association constant is obtained from the differences of the molar conductivity of Ce(III) solution at various concentrations in presence and absence of PCR5. When Tb(III) is adsorbed on PCR5 membranes, lifetime experiments in H2O and D2O confirm the loss of 5 or 6 water coordinated molecules indicating that in solid state the lanthanide(III)‐PCR5 interaction is stronger than in solution. The adsorption of Ce(III) in PCR5 membranes shows a Langmuir type isotherm, from which an equilibrium constant of 39 M?1 has been calculated. SEM shows that the membrane morphology is not much affected by lanthanide adsorption. Support for lanthanide ion–crown interactions comes from ab initio calculations on 15‐crown‐5/La(III) complex. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1788–1799, 2007  相似文献   

19.
Phase formation and transition in a xanthan gum (XG)/H2O/H3PO4 tertiary system were characterized by polarized optical microscopy, light transmission detection and rheological methods. Three distinct phases and a transition region—the completely separated (S) phase, the liquid crystalline (LC) miscible phase, the isotropically (I) miscible phase and the S plus LC region—were identified. The presence of H3PO4 in the XG/H2O system inhibited the evolution of both the S and LC phases. The S and LC phases contained less than 73 and 62 wt% of H3PO4, respectively. As the temperature increased over 65 °C, the LC phase in the H3PO4-rich and H2O-poor region seriously shrunk owing to the breakup of hydrogen bonds among the XG helical structure. At the same XG loading, the viscosity of the XG solutions in LC phase was found to be much higher than that in I phase. It indicated the existence of numerous XG intermolecular interactions in the LC phase that suppress the movement of liquid. A study of the kinetics demonstrated that the shrinkage relaxation time (τ) depended strongly on temperature and was fitted by the Volgel-Fulcher-Tammann (VFT) expression. The potential energy barrier of this liquid was quite low at approximately 3.0 kJ mol?1, falling in the range of hydrogen-bond disassociation. The light absorbance test in heating mode revealed a biphasic transitional region between the LC phase and I phase. The contour of this region depended on the heating rate, and this fact was explained again by the relaxation behavior of XG helices at temperatures higher than 65 °C.  相似文献   

20.
A novel labeling reagent 1-(2-naphthyl)-3-methyl-5-pyrazolone (NMP) coupling to liquid chromatography with electrospray ionization mass spectrometry for the detection of carbohydrates from the derivatized rape bee pollen samples is reported. Carbohydrates are derivatized to their bis-NMP-labeled derivatives. Derivatives showed an intense protonated molecular ion at m/z [M+H]+ in positive-ion detection mode. The mass-to-charge ratios of characteristic fragment ions at m/z 473.0 could be used for the accurately qualitative analysis of carbohydrates. This characteristic fragment ion is from the cleavage of C2–C3 bond in carbohydrate chain giving the specific fragment ions at m/z [MH-C m H2m+1O m -H2O]+ for pentose, hexose and glyceraldehydes and at m/z [MH-C m H2m-1O m+1-H2O]+ for alduronic acids such as galacturonic acid and glucuronic acid (m = n ? 2, n is carbon number of carbohydrate). No interferences for all aliphatic and aromatic aldehydes presented in natural environmental samples were observed due to the highly specific parent mass-to-charge ratio and the characteristic fragment ions. The method, in conjunction with a gradient elution, offered a baseline resolution of carbohydrate derivatives on a reversed-phase Hypersil ODS-2 column. The carbohydrates such as mannose, galacturonic acid, glucuronic acid, rhamnose, glucose, galactose, xylose, arabinose and fucose can successfully be detected.  相似文献   

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