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1.
Liquid-liquid extraction of zirconium(IV) was investigated from dilute hydrochloric acid medium by salicyaldoxime (HA) in dichloromethane. The metal was spiked with 95Zr and analyzed by its radioactivity. The effects of different donors, like trioctyl phosphine oxide (TOPO), triphenyl phosphine oxide (TPPO), tributyl phosphine oxide (TBPO), tributyl phosphate (TBP), trioctyl amine (TOA) and Amberlite LA-2 were studied. The adduct formation constants for both binary species (metal-ligand) and ternary species (metal-ligand-donor) were also calculated form the distribution data.One of the authors (S.B.) thanks The University of Burdwan for providing senior research fellowship to her. She also wishes to thank Dr. D. Mukherjee and Dr. S. Bhattacharya, B.U. for their valuable suggestions.  相似文献   

2.
Synergistic effect with a strong donor, trioctyl phosphine oxide (TOPO), has been studied in the extraction of thenoyltrifluoroacetone (TTA) complexes of uranyl ion. The chemical form of the species extracted was found to be the 1∶1 adduct, UO2A2·S (S∶TOPO), and no evidence was found concerning other mixed complexes. Adduct formation constants determined in twelve inert solvents vary from lg KS=6.79 in chloroform to 9.58 in n-hexane, while their increasing order is almost the same as that for the adducts with other phosphine oxides and TBP.  相似文献   

3.
Synergistic effect of neutral donors like tri-butyl phosphate (TBP), triphenyl phosphine oxide (TPPO), trioctyl phosphine oxide (TOPO), and dimethyl sulphoxide (DMSO) on the extraction of uranium(VI) by tri-isooctyl amine into CCl4 is reported. Synergistic coefficients and adduct formation constants are calculated from distribution data and correlated with relative donor abilities of added bases.  相似文献   

4.
HNO3 is extracted in significant quantities by uranyl nitrate solvates with different extractants: TBP (tributyl phosphate), TOPO (trioctyl phosphine oxide) and TDA (tetradecyl ammonium). The effect of diluent nature is not observed on extracting HNO3 and TBP saturated by uranium at equilibrium with its salt using the diluents (CCl4, C6H5Cl, C12H26, CHCl3) which are less polar than UO2(NO3)2(TBP)2. HNO3 occurs in organic phase as undissociated form and its state is similar to pure anhydrous HNO3. Solvates of TBP and TDA with uranyl nitrate dissolve HNO3 without displacement of uranium from organic phase.  相似文献   

5.
The studies on ion transport of terbium and dysprosium through a porous supported liquid membrane (SLM) containing TOPO (trioctyl phosphine oxide) and TBP (tributyl phosphate) as immobilised carriers have been carried out. The effect of stirring of bulk solutions on permeability coefficient has been investigated. The permeability coefficient increases with increase in pH of source phase from 0–6, and hydrogen ion concentration from 0.01 to 0.1 M of receiving solution. The dependency of permeability coefficient on the carrier concentration has been explored. The effect of ammonium thiocyanate concentration on permeability coefficient has been studied. In order to develop a method for enrichment of rare earth elements, further investigations were carried out by using a hollow fibre membrane extractor. The mechanism of ion transport of terbium and dysprosium in SLM systems has been explained.  相似文献   

6.
The extraction ability and selectivity of a series of phosphoryl ketones Ph2P(O)CH2C(O)Me, and Ph2P(O)CRR’CH2C(O)Me (R = H, Me; R’ = H, Me, n-C5H11, Ph, 2-thienyl, 2-furyl) towards trivalent lanthanides (LaIII, NdIII, HoIII, YbIII) and actinides (UVI, ThIV) were studied. The efficiency and selectivity of the new ligands in the extraction of f-elements from nitric acid solutions into chloroform were compared to those of model phosphine oxide Ph2P(O)Bu and known extractants: tributyl phosphate (BuO)3P(O), trioctylphosphine oxide (C8H17)3P(O), and carbamoylmethyl phosphine oxide Ph2P(O)CH2C(O)NBu2.  相似文献   

7.
Summary Conditions are described for the quantitative precipitation of bismuthyl dichromate, (BiO)2Cr2O7, and the suitability of this reaction for the gravimetric estimation of bismuth is shown. The use of arsenious oxide as a primary standard for the iodometric titration of excess chromate is emphasised.Sincere thanks of the authors are due to Prof. S. S. Joshi for research facilities and to Dr. G. S. Deshmukh for keen interest in the work.  相似文献   

8.
Diphenyl[2-(trifluorosilyl)ethyl]phosphine oxide was synthesized by the reaction of diphenyl[2-(triethoxysilyl)ethyl]phosphine oxide with boron trifluoride etherate. As shown by the 1H, 13C, 19F, 31P, 29Si multinuclear NMR spectroscopy data, the silicon atom in the molecule is tetracoordinate. The absence of P=O→Si interaction in diphenyl[2-(trifluorosilyl)ethyl]phosphine oxide, as follows from the comparison of the calculated [GIAO B3LYP/6-311++G(2d,p)] and experimental δ(29Si) and δ(31P) values, is due to the formation of complex with BF3 by the phosphoryl oxygen.  相似文献   

9.
An infrared furnace (ULVAC RHL-410P) was newly applied to the extraction of tritium from concrete samples. After studying the tritium recovery yield regarding temperature and time, the best extraction conditions were set to 800 °C (setting temperature) for 30 minutes under Ar-gas flow of 200 ml/min. Tritium was collected in two cold traps and transferred to a vial for liquid scintillation counting. It took about one hour for the extraction of tritium. Reproducibility and recovery yield of tritium were about 100% compared to the values obtained by the ordinary heating method using an electric furnace. Gamma-ray emitters and tritium of concrete samples collected from several accelerator facilities have been determined. The specific activity of tritium strongly correlated with that of 152Eu and 60Co, so it was found that tritium was produced by thermal neutron reaction by the 6Li(n,)3H reaction. The results indicate that the tritium specific activity in concrete can be estimated from the 60Co specific activity obtained easily by -ray measurement.On leave from IHEP, Beijing.This work was supported by Japan Society for the Promotion of Science. The authors also are grateful to Dr. S. Watanabe, Center for Nuclear Study, University of Tokyo, Dr. T. Ohtsuki, Laboratory of Nuclear Science, Tohoku University, and Dr. T. Saito, Research Center for Nuclear Physics, Osaka University, and their colleagues for concrete sampling.  相似文献   

10.
Extraction behavior of some selected actinides like U(VI), Th(IV), and Am(III) was investigated with three different H-phosphine oxides, viz. diphenyl hydrogen phosphine oxide (DPhPO), dihexyl hydrogen phosphine oxide (DHePO) and diphenyl phosphite (DPP). The H-phosphine oxides exhibited a dual nature towards the extraction of actinides where the ligand not only extracts the metals by cation exchange but also by coordination with the phosphoryl group at lower and higher acidic concentrations, respectively. Among all ligands employed, DPhPO showed highest extraction with actinides with a substituent dependent trend as follows: DPhPO > DHePO > DPP. This trend emphasizes the importance of substituents around the phosphine oxide towards their extraction of actinides. The coordination behavior of DPhPO was studied by investigating its corresponding complexes with Th(NO3)4 and UO2(NO3)2. The metal complexes of these actinides were characterized using FT-IR, 1H and 31P NMR spectroscopic techniques. Density Functional Theory (DFT) calculations were also performed to understand the electronic and geometric structure of the ligand and the corresponding metal complexes.  相似文献   

11.
Effect of structure on thermal behaviour of epoxy resins   总被引:1,自引:0,他引:1  
The paper deals with the curing behaviour of diglycidyl ether of bisphenol-A (DGEBA) using three novel multifunctional aromatic amines having phosphine oxide and amide-acid linkages. The amines were prepared by reacting tris(3-aminophenyl)phosphine oxide (TAP) with 1,2,4,5-benzenetetracarboxylic acid anhydride (P)/4,4-(hexafluoroisopropylidene)diphthalic acid anhydride (F)/3,3,4,4-benzophenonetetracarboxylic acid dianhydride (B). Amide-acid linkage in these amines is converted to thermally stable imide linkage during curing reaction. Curing temperatures of DGEBA were higher with phosphorylated amines than the conventional amine 4,4-diamino diphenyl sulphone (D). A decrease in initial decomposition temperature and higher char yields were observed when phosphorus containing amide-acid amines were used as curing agents for DGEBA.  相似文献   

12.
The lithium ion selectivity of the dibenzo-14-crown-4 (DB14C4) liquid-membrane electrode increases with the concentration of DB14C4 om the membrane. The lithium ion selectivity was enhanced by an addition of organophosphorus compounds such as trioctyl phosphine oxide.  相似文献   

13.
An infrared furnace (ULVAC RHL-410P) was newly applied to the extraction of tritium from concrete samples. After studying the tritium recovery yield regarding temperature and time, the best extraction conditions were set to 800 °C (setting temperature) for 30 minutes under Ar-gas flow of 200 ml/min. Tritium was collected in two cold traps and transferred to a vial for liquid scintillation counting. It took about one hour for the extraction of tritium. Reproducibility and recovery yield of tritium were about 100% compared to the values obtained by the ordinary heating method using an electric furnace. Gamma-ray emitters and tritium of concrete samples collected from several accelerator facilities have been determined. The specific activity of tritium strongly correlated with that of 152Eu and 60Co, so it was found that tritium was produced by thermal neutron reaction by the 6Li(n,)3H reaction. The results indicate that the tritium specific activity in concrete can be estimated from the 60Co specific activity obtained easily by -ray measurement.On leave from IHEP, Beijing.This work was supported by Japan Society for the Promotion of Science. The authors also are grateful to Dr. S. Watanabe, Center for Nuclear Study, University of Tokyo, Dr. T. Ohtsuki, Laboratory of Nuclear Science, Tohoku University, and Dr. T. Saito, Research Center for Nuclear Physics, Osaka University, and their colleagues for concrete sampling.  相似文献   

14.
Hydrated iron oxide or amorphous-Fe2O3·3.5 H2O (HFeO), hydrated titanium oxide (HTiO) and hydrated thorium oxide (HThO) were synthesized and their applicability for the decontamination of intermediate level liquid wastes (ILLW) was tested. The sorption of a few actinides like plutonium and americium on HFeO, 137Cs and 106Ru on HTiO and 90Sr on HThO was investigated as a function of pH, time and loading capacity of the hydrous oxide with metal ions. The influence of the total dissolved salt content was also monitored. Some of these parameters influenced the sorption behavior significantly. The radiation stability of these inorganic sorbents were studied by irradiating them up to 48 Mrad. Adsorbed actinides and fission products were successfully eluted from HFeO and from the mix-bed of HTiO and HThO by 0.5M nitric acid.The authors wish to thank Shri R. D. Changarani, Chief Superintendent NRG Facilities and Shri P. K. Dey, Head FRD for their valuable advice and constant support.  相似文献   

15.
Hydrated iron oxide or amorphous-Fe2O3·3.5 H2O (HFeO), hydrated titanium oxide (HTiO) and hydrated thorium oxide (HThO) were synthesized and their applicability for the decontamination of intermediate level liquid wastes (ILLW) was tested. The sorption of a few actinides like plutonium and americium on HFeO, 137Cs and 106Ru on HTiO and 90Sr on HThO was investigated as a function of pH, time and loading capacity of the hydrous oxide with metal ions. The influence of the total dissolved salt content was also monitored. Some of these parameters influenced the sorption behavior significantly. The radiation stability of these inorganic sorbents were studied by irradiating them up to 48 Mrad. Adsorbed actinides and fission products were successfully eluted from HFeO and from the mix-bed of HTiO and HThO by 0.5M nitric acid.The authors wish to thank Shri R. D. Changarani, Chief Superintendent NRG Facilities and Shri P. K. Dey, Head FRD for their valuable advice and constant support.  相似文献   

16.
A novel diamine, bis‐(3‐aminophenyl)‐4‐(trifluoromethyl)phenyl phosphine oxide (mDA3FPPO), containing phosphine oxide and fluorine moieties was prepared via the Grignard reaction from an intermediate, 4‐(trifluoromethyl)phenyl diphenyl phosphine oxide, that was synthesized from diphenylphosphinic chloride and 4‐(trifluoromethyl)bromobenzene, followed by nitration and reduction. The monomer was characterized by Fourier transform infrared (FTIR), 1H NMR, 31P NMR, 19F NMR spectroscopies; elemental analysis; melting point measurements; and titration and was used to prepare polyimides with a number of dianhydrides such as pyromellitic dianhydride (PMDA), 5,5′‐[2,2,2‐trifluoro‐1‐(trifluoromethyl)ethyliden]‐bis‐1,3‐isobenzofuranedione (6FDA), 3,3′,4,4′‐benzophenone tetracarboxylic dianhydride (BTDA), and 4,4′‐oxydiphthalic dianhydride (ODPA). Polyimides were synthesized via a conventional two‐step route; preparation of polyamic acids, followed by solution imidization, and the molecular weight were controlled to 20,000 g/mol. Resulting polyimides were characterized by FTIR, NMR, DSC, and intrinsic viscosity measurements. Refractive‐index, dielectric constant, and adhesive properties were also determined. The properties of polyimides were compared with those of polyimides prepared from 1,1‐bis‐(4‐aminophenyl)‐1‐phenyl‐2,2,2‐trifluoroethane (3FDAm) and bis‐(3‐aminophenyl) phenyl phosphine oxide (mDAPPO). The polyimides prepared from mDA3FPPO provided high glass‐transition temperatures (248–311 °C), good thermal stability, excellent solubility, low birefringence (0.0030–0.0036), low dielectric constants (2.9–3.1), and excellent adhesive properties with Cu foils (107 g/mm). © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3335–3347, 2001  相似文献   

17.
Summary Stability constants for mixed-ligand complexes of the types [NiABH2], [NiABH] and [NiAB] formed by NiII with l-cysteine (cys), d-penicillamine (pen) or l-cysteic acid (cya) as ligand A and dl-2,3-diaminopropionic acid (dapa), dl-2,4-diaminobutyric acid (daba) or dl-ornithine (orn) as ligand B have been determined by the computerbased analysis of pH titration data obtained at 37 °C and I = 0.15 mol dm–3 (NaClO4). In the [NiABH] species, for all three secondary ligands (B), when A = pen or cya the labile proton appears to be attached to the terminal amino group of ligand B, whereas when A = cys it is not clear where the proton is located. In all the systems in the [NiABH2] species, one proton resides with the primary ligand (A) and the other with the secondary ligand (B). In the [NiAB]-type complexes, cys and pen chelate through the amino and thiolato groups, while cya binds in a glycine-like mode and the secondary ligands (B) coordinate in a terdentate manner.Author to whom all correspondence should be directed.  相似文献   

18.
Summary A method is described for the routine determination of ethylene oxide and propylene oxide, and of C1-nC4 alkoxyl groups. It was found that monomeric propylene oxide yields isopropyl iodide and propylene when decomposed by hydriodic acid, but the decomposition of propylene oxide polymers results mainly in the formation of isopropyl iodide (68%) and propionaldehyde (22%): less than 1% of propylene is formed and seven other compounds are also present. Those of the latter that were present in amounts 1% were identified. These results were taken into account in working out the quantitative method.The sample is decomposed in boiling hydriodic acid, volatile products are collected in m-xylene in a cold trap, and ethylene and propylene are measured in a gas burette (nitrometer). 1,1,2-Trichlorethane is added to the m-xylene solution as internal standard, and C1-nC4 iodides and propionaldehyde are determined gaschromatographically with Apiezon L on kieselguhr as stationary phase. The time required is 1 hr after the decomposition of the sample is complete, but the working time per sample is less if a series of samples is analysed.

Meinem verehrten Lehrer, Herrn Prof. Dr. Hans Lieb, zum 80. Geburtstag gewidmet.

Herrn Dr. Pfab danke ich. für wertvolle Hinweise, Herrn Dr. Noffz für Beratung und anregende Diskussion bei der Einrichtung der Gas-Chromatographie. Die massenspektrometrischen Untersuchungen wurden in dankenswerter Weise von Herrn Dr. Benz, die Papier- und Dünnschicht-Chromatographie von Herrn Dr. Steuerle ausgeführt. Für die gewissenhafte Ausführung der Versuche sei auch an dieser Stelle Herrn Niklas gedankt.  相似文献   

19.
A combined radiochemical separation method has been developed that enables the simultaneous determination of 234U, 235U, 238U, 237Np, 239,240Pu, 238Pu, 241Am, 242Cm, and 244Cm in medium and low level liquid radioactive wastes. The main steps of the method are sample destruction, co-precipitation on iron(II)-hydroxide and calcium-oxalate, separation by extraction chromatography using supported dipentyl-pentyl phosphonate (UTEVA) and supported N,N-octylphenyl-di-i-butylcarbamoylmethyl phosphine oxide with tributyl phosphate (TRU), and α source preparation. The key parameter of the method is the adjustment of the oxidation states of the actinoides before adding the sample onto the UTEVA column. It has been determined that (NH4)2S2O8 can be used for oxidation state adjustment resulting sufficient chemical yields.  相似文献   

20.
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   

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