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1.
Probabilities of gamma-ray simultaneous emission have been calculated for the determination of correction factors of full-energy peak areas of radionuclides with a complex decay scheme at measurements of gamma-spectra using HPGe detectors. Coincidence probabilities were determined using the Monte Carlo method for the following radionuclides: 22Na, 24Na, 46Sc, 51Cr, 52Fe, 54Mn, 56Co, 57Co, 58Co, 59Fe, 60Co, 64Cu, 65Zn, 67Cu, 68Ge-68Ga, 75Se, 85Sr, 88Y, 94Nb, 108mAg, 109Cd, 111In, 124Sb, 125Sb, 125I, 131I, 132Cs, 133Ba, 134Cs, 139Ce, 152Eu, 153Sm, 153Gd, 155Eu, 166mHo, 169Yb, 177Lu, 186Re, 207Bi, 208Tl, 212Pb, 212Bi, 241Am.  相似文献   

2.
The recombination energy of N22+ has been computed using N22+, N22+ and N2 potential curves from the literature. Vibrational overlaps and energies liberated in the various N22+3?g,1g+, 3Πu, 1Πu → N2+(X2+g, A 2+g, A 2Πu, B2u+,C2u+) vibronic transitions have been computed and used as input for determination of the N2+ recombination energy.  相似文献   

3.
The CASPT2 potential energy curves (PECs) for O‐loss dissociation from the X2Π, A2Π, B2Σ+, C2Σ+, 14Σ?, 12Σ?, and 14Π states of the OCS+ ion were calculated. The PEC calculations indicate that X2Π, 14Σ?, 12Σ?, and 14Π correlate with CS+(X2Σ+) + O(3Pg); A2Π and B2Σ+ correlate with CS+(A2Π) + O(3Pg); and C2Σ+ probably correlates with CS+(X2Σ+) + O(1Dg). The CASSCF minimum energy crossing point (MECP) calculations were performed for the C2Σ+/14Σ?, C2Σ+/14Π, A2Π/14Σ?, A2Π/12Σ?, A2Π/14Π, and B2Σ+/12Σ? state pairs and the spin‐obit couplings were calculated at the located MECPs. A conical intersection point between the B2Σ+ and C2Σ+ potential energy surfaces was found at the CASSCF level. Based on our calculations, seven O‐loss predissociation processes of the C2Σ+ state are suggested and an appearance potential value of 7.13 eV for the CS+ + O product group is predicted. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011  相似文献   

4.
In this article, the angular correlated configuration interaction method previously introduced by some of the authors is extended to three‐body atomic systems with general masses. A recently proposed angularly correlated basis set is used to construct ground state wave functions which: (i) satisfy exactly Kato cusp conditions at the two‐body coalescence points; (ii) have only linear coefficients; and (iii) show a fast convergency rate for the energy. The efficiency of the construction is illustrated by the study of the negatively charged hydrogen‐like systems (H?, T?, D?, 1H?, and Mu?), neutral helium‐like systems (e?e? He+2,e?e? 4He+2, e?e? 3He+2, e?μ? He+2, e?μ ?4He+2, and e?μ? 3He+2), and positively charged lithium‐like systems (e?e? Li+3, e?e? 7Li+3, e?e? 6Li+3, e?μ? Li+3, e?μ? 7Li+3, and e?μ? 6Li+3). The ground state energies and other mean values are compared with those given in the literature, when available. Wave functions with a moderate number of (20 maximum) linear coefficients are given explicitly; they are sufficiently simple and accurate to be used in practical calculations of atomic collision in which multidimensional integrations are involved. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010  相似文献   

5.
Summary Relatively short-lived radioactive nuclides of cosmogenic origin, such as7Be (T1/2=53.3 d),32P (14.3 d),33P (25.3 d),35S (87.4 d) as well as22Na (2.6 y) have come to be recognized as potential tools to trace environmental processes, such as precipitation, washout (precipitation scavenging), resuspension, atmospheric particle deposition and deposition patterns of airborne contaminants, aerosol deposition and aerosol trapping by above ground vegetation (air-to-vegetation transfer). Of the above radionuclides,7Be as well as210Pb of terrestrial origin and137Cs, a fission product radionuclide, are commonly used for determining the atmospheric particle deposition parameters. It was found that the deposition velocity of7Be-associated aerosol particles varied from 0.3 to 0.8 cm. s-1(average 0.5 cm. s-1), the washout ratio for7Be varied from 103 to 375 (average 144), the resuspension factor for the7Be-associated particles varied from 1.6. 10-4to 4.2. 10-4m-1(average 2.3. 10-4m-1) and the air-to-vegetation transfer rate for7Be varied from 5258 to 16180 m3.kg-1(average 9856 m3.kg-1) for grass, gramineae or poaceae the species. For the137Cs-associated aerosol particles the deposition velocity varied from 1.3 to 6.3 cm. s-1(average 3.4 cm. s-1), the washout ratio for137Cs varied from 284 to 3810 (average 1295), the resuspension factor for the137Cs-associated aerosol particles varied from 0.1. 10-4to 1.2. 10-4m-1(average 0.6. 10-4m-1) and the air-to-vegetation transfer rate for137Cs varied from 39638 to 345279 m3.kg-1(average 181197 m3.kg-1) for grass, gramineae or poaceaethe species.  相似文献   

6.
Summary Direct titrimetric method for the estimation of uranium(VI) in the range of 0.7 to 76 mg is performed by decomposing and oxidising the complex, {U(VI)O2 · U(V)O2 · Fe(CN)6}, with ceric sulphate. The mixed valency state in the above mentioned complex has been confirmed by magnetic measurements, the isolated complex being paramagnetic. Na+, K+, Cs+, Ca2+, Sr2+, Mg2+, Be2+, Pd2+, La3+, Ir3+, Ru3+, and Te4+ do not interfere but Ag+, Tl+, Cu2+, Ba2+, CO2+, Ni2+, Zn2+, Pb2+, Hg2+, Sn2+, Bi3+, Au3+, Rh3+, Sb3+, In3+, Ti3+, Th4+, Zr4+, Pt4+, V5+, Se6+, MO6+, and Os8+ do.
Zusammenfassung Die Bestimmung von Uran(VI) in der Größenordnung von 0,7 bis 76 mg erfolgt durch Zersetzung und Oxydation des Komplexes U(VI)O2 · U(V)O2 · · Fe(CN)6 mit Cer(IV) sulfat. Die zweierlei Wertigkeitsstufen in diesem paramagnetischen Komplex wurden durch magnetische Messungen bestätigt. Na+, K+, Cs+, Ca2+, Sr2+, Mg2+, Be2+, Pd2+, La3+, Ir3+, Ru3+, and Te4+ stören nicht; hingegen stören Ag+, Tl+, Cu2+,Ba 2+, CO2+, Ni2+, Zn2+, Pb2+, Hg2+, Sn2+, Bi3+, Au3+, Rh3+, Sb3+, In3+, Ti3+, Th4+, Zr4+, Pt4+, V5+, Se6+, MO6+, and Os8+.
  相似文献   

7.
Summary A method for titrimetric determination of lanthanum is proposed by oxidising lanthanum rhodizonate with ceric sulphate directly. A violet coloured complex is precipitated when the solution containing sodium rhodizonate and lanthanum nitrate is boiled. By analysis it appears that with one lanthanum three rhodizonates are attached. It is observed that Na+, K+, and Zr4+ do not interfere but Ag+, Cs+, Tl+, Be2+, Ca2+, Sr2+, Ba2+, Zn2+, Mg2+, Hg2+, Cu2+, Sn2+, Pd2+, Bi3+, Au3+, Sb3+, Al3+, Rh3+, Ru3+, Ir3+, Th4+, Te4+, Pt4+, Se6+, Cr6+, W6+, and U6+ do.
Zusammenfassung Zur maßanalytischen Bestimmung von Lanthan wird die unmittelbare Oxydation von Lanthanrhodizonat mit Cer(IV)-sulfat vorgeschlagen. Beim Kochen einer Lösung von Natriumrhodizonat und Lanthannitrat fällt ein violett gefärbter Komplex aus. Aus der Analyse ergibt sich das Verhältnis La: Rhodizonat =13. Na+, K+ und Zr4+ stören nicht im Gegensatz zu Ag+, Cs+, Tl+, Be2+, Ca2+, Sr2+, Ba2+, Zn2+, Mg2+, Hg2+, Cu2+, Sn2+, Pd2+, Bi3+, Au3+, Sb3+, Al3+, Rh3+, Ru3+, Ir3+, Th4+, Te4+, Pt4+, Se6+, Cr6+, W6+, und U6+.
  相似文献   

8.
In order to evaluate the possible radiological impact to the local public and environment from a phosphogypsum stockpile, 210Po and 210Pb concentrations in river water, lagoon water, suspended matter, superficial sediment, algae and bivalves samples collected in Venice lagoon area have been investigated. The results show that the mean 210Po and 210Pb concentrations in river water are 1.42±0.36 mBq.l-1 and 1.46±0.39 mBq.l-1 with a mean 210Po/210Pb ratio of 0.98±0.17 and about 60% of them are associated with the particulate; 210Po and 210Pb contribution from the phosphogypsum stockpile to the river water is negligible. Higher 210Po (2.61-5.67 mBq.l-1) and 210Pb (1.31-3.62 mBq.l-1) concentrations in the lagoon waters have been observed if compared with the literature values. About 60% of 210Po and 210Pb are found in the soluble form with a mean 210Po/210Pb ratio of 1.79±1.47. 210Po and 210Pb concentrations in 28 out 37 sediment samples ranged from 26 to 45 Bq.kg-1 (dry weight), only 9 sediments with 210Po and 210Pb concentrations greater than 45 Bq.kg-1 are found and most of them are located 1-4 km near the phosphogypsum stockpile. The elevated 210Po and 210Pb concentrations in the sediments may be due to the contamination from the phosphogypsum stockpile. The mean 210Po/210Pb ratio (0.986±0.049) in the sediments shows that 210Po and 210Pb exist in nearly secular equilibrium. 210Po and 210Pb concentrations in algae vary with different species. The mean 210Po and 210Pb concentrations in Gracilaria compress and Ulva laetevirens which show a similar behavior, are 3.18±1.23 Bq.kg-1 and 2.42±1.26 Bq.kg-1 (fresh weight), respectively, with a mean 210Po/210Pb ratio of 1.45±0.34. The mean concentration factors with respect to the filtered water are 1096±424 for 210Po and 1299±680 for 210Pb. The mean 210Po and 210Pb concentrations in the soft part of Mytilus edulis are 23.2±9.7 Bq.kg-1 and 0.537±0.203 Bq.kg-1 (fresh weight), respectively, with a mean 210Po/210Pb ratio of 43.6±10.0. The mean concentration factors with respect to the filtered water are 8006±3351 for 210Po and 290±109 for 210Pb, showing a very high accumulation effect for 210Po. The accumulation behaviors of Cerastoderma glaucum and Tapes philippinarum for 210Po are similar to Mytilus edulis, but that for 210Pb seems less effective, corresponding to a relatively higher 210Po/210Pb ratio. The estimated committed effective doses from 210Po for the individual local public through ingestion of bivalves are in the range of 0.050-0.231 mSv.y-1.  相似文献   

9.
Frans J.C. Martins 《Tetrahedron》2009,65(15):2921-2926
Treatment of hexacyclo[7.4.2.01,9.03,7.04,14.06,15]pentadecane-10,12-diene-2,8-dione with aqueous sodium cyanide produced 2,8-dihydroxy-hexacyclo[7.4.2.01,9.03,7.04,14.06,15]pentadecane-10,12-diene-2,8-lactam and with sodium cyanide, ammonium chloride and ammonium hydroxide, 2-amino-8-hydroxy-hexacyclo [7.4.2.01,9.03,7.04,14.06,15]pentadecane-10,12-diene-2,8-lactam was obtained. 10-Hydroxy-hexacyclo [10.2.1.02,11.04,10.04,14.09,13]pentadecane-5,7-diene-3-one was converted into the corresponding aminonitrile and hexacyclo[10.2.1.02,11.04,10.04,14.09,13]pentadecane-5,7-diene-10-hydroxy-3-spiro-5′-hydantoin. Treatment of the latter with barium hydroxide produced exo-3-amino-10-hydroxy-hexacyclo [10.2.1.02,11.04,10.04,14.09,13]pentadecane-5,7-diene-endo-3-carboxylic acid. The isomeric endo-3-amino-10-hydroxy-hexacyclo[10.2.1.02,11.04,10.04,14.09,13]pentadecane-5,7-diene-exo-3-carboxylic acid was obtained from 3-cyano-3-ureido-hexacyclo[10.2.1.02,11.04,10.04,14.09,13]pentadecane-5,7-diene-10-ol.  相似文献   

10.
Abstract

Organic salts as initiators [A? +B?: Ph?3C+ClO? 4, Ph?3C+SbCl? 6, (?)Sp? +ClO? 4, and (?)(Sp)?2 3+(ClO4)? 3] and catalysts [A +B??: (+)CSA?; A? +B??: ph?3C+(+)CSA?? and (?)Sp?+(+)CSA??] are prepared and characterized by the dissociation constant (K d), fraction of free ions (α), and specific rotation. The asymmetrically stereoselective induction of the initiators and catalysts in the polymerization of N-vinylcarbazole is in the order A? +B?? > A +B?? > A? +B?. The specific rotations of the poly(N-vinylcarbazole) (PVCZ)s obtained are generally in this order.  相似文献   

11.
After single electron reduction of the dinitrogen complex [LtBuNi(μ‐η11‐N2)NiLtBu] ( I ) with KC8, reaction of the resulting compound K[LtBuNi(μ‐η11‐N2)NiLtBu] ( II ) with sodium sand yields KNa[LtBuNi(μ‐η11‐N2)NiLtBu] ( 1 ), which contains two different alkali metal ions. Treatment of I with two equivalents of sodium sand leads to the symmetric complex Na2[LtBuNi(μ‐η11‐N2)NiLtBu] ( 2 ). Complexes 1 and 2 were investigated by single crystal X‐ray diffraction analysis as well as by Raman spectroscopy, and the results were compared with the data of K2[LtBuNi(μ‐η11‐N2)NiLtBu] ( III ), which contains two K+ ions. Thus, it became obvious that the nature of the alkali metal ion M in compounds M2[LtBuNi(μ‐η11‐N2)NiLtBu] has hardly any influence on the degree of NN bond activation. Furthermore, it was shown that treatment of the dinickel(I) complex III with CO leads to the dinickel(0) compound K2[LtBuNi(CO)]2 ( 4 ) and N2. Reaction of the unreduced dinickel(I) complex I with CO leads to a more simple replacement of the N2 ligand and formation of [LtBuNi(CO)] ( 3 ).  相似文献   

12.
《Analytical letters》2012,45(11):865-871
Abstract

A nitron-polyvinylbenzyl chloride polymer was found to have a strong preference for oxidizing anions such as NO3 ?, NO2 ?, ReO4 ?, MnO4 ?, C1O4 ?, C1O3 ?, and Cr2O7 = but not for the non-oxidizing anions SO4 =, HSO4 ?, H2PO4 =, HPO4 =, PO4 =, OH?, CO3 =, HCO3 ?, F?, C1?, and Br?.  相似文献   

13.
Two low cytotoxic fluorescence probes Rb1 and Rb2 detecting Fe3+ were synthesized and evaluated. Rb1 and Rb2 exhibited an excellent selectivity to Fe3+, which was not disturbed by Ag+, Li+, K+, Na+, NH4+, Fe2+, Pb2+, Ba2+, Cd2+, Ni2+, Co2+, Mn2+, Zn2+, Mg2+, Hg2+, Ca2+, Cu2+, Ce3+, AcO?, Br?, Cl?, HPO42?, HSO3?, I?, NO3?, S2O32?, SO32? and SO42? ions. The detection limits were 1.87 × 10?7 M for Rb1 and 5.60 × 10?7 M for Rb2, respectively. 1:1 stoichiometry and 1:2 stoichiometry were the most likely recognition mode of Rb1 or Rb2 towards Fe3+, and the corresponding OFF–ON fluorescence mechanisms of Rb1 and Rb2 were proposed.  相似文献   

14.
Abstract

The ion exchange potential of antimonic acid and silica gel ‘G’ has been explored in thin layer chromatographic studies for the separation of anions. Several important and difficult binary separations of anions have been achieved as a result of these studies. Io? 3-Bro? 3, I?-Io? 3, Io? 4-Io? 3, Io? 4-Po?- 4, Br?-Bro? 3, Aso?- 4-Cro?- 4, S2o?- 3-Po?- 4, CNS?-S2o?- 3, Io? 4-Cro?- 4, Bro? 3-Cro?- 4, Io? 3-Cr2o?- 7 and s2o3-Cro?- 4 etc. are separations of analytical interest. Besides, a rapid microgram determination of [Fe(CN)6]3? (1–10 μg) and Cr2o2- 7 (2–10 μg) ions have been made.  相似文献   

15.
Using an MC SCF CI method, wavefunctions for the ground state 1+g and the excited states of the symmetries 1+g, 1Πg, and 1Δg of the Cs2+2 ionic system are generated. The potential curves for eleven 1+g twelve 1Πg, and six 1Δg states are calculated. Results suggest a small charge-transfer cross section for the reaction CS+ + Cs+ → Cs CS2+.  相似文献   

16.
Summary Phenyl acetic acid has been found to be a selective reagent for the estimation of zirconium. The acid gives a white crystalline precipitate which is quantitative between pH values of 3.00 to 5.40. As the composition of the precipitate varies somewhat, direct weighing is not possible and the compound is ignited to the oxide. The ions Be2+, Ca2+, Sr2+, Zn2+, Hg2+, Pb2+, Mg2+, Ni2+, and Co2+ do not interfere, whereas the ions Fe3+, UO2 2+, Cr3+, Ba2+, Au+, Al3+, V2O4 2+, Ti4+, Sn2+, and Ba2+ cause interferences in the estimation.
Zusammenfassung Zur gravimetrischen Bestimmung von Zirkonium wird Phenylessigsäure empfohlen. Die weiße, kristalline Fällung ist im pH-Bereich 3,00–5,40 quantitativ. Infolge schwankender Zusammensetzung des Niederschlages ist eine direkte Wägung nicht möglich; er wird daher zum Oxid verglüht. Folgende Ionen stören nicht: Be2+, Ca2+, Sr2+, Zn2+, Hg2+, Pb2+, Mg2+, Ni2+ und Co2+; dagegen verursachen Fe3+, UO2 2+, Cr3+, Ba2+, Au+, Al3+, V2O4 2+, Ti4+, Sn2+ und Ba2+ Störungen bei der Bestim mung.


Part VI: See Z. analyt. Chem. 175, 29 (1960).  相似文献   

17.
Zusammenfassung Die Trennung der Ionenpaare Rb+/Cs+, K+/Rb+, K+/Cs+, Na+/K+, Li+/Na+ mit Salzsäure oder Ammoniumchloridlösung als Elutionsmittel gelingt quantitativ oder nahezu quantitativ mit Hilfe von Titanhexacyanoferrat(II)-säulen. Die Cäsiumionen können nicht eluiert werden. Ebenso gelingt die Trennung der lonenpaare Sr2+/Ba2+, Ca2+/Ba2+, Ba2+/Cs+ und Sr2+/Cs+ quantitativ oder nahezu quantitativ. Auch eine partielle Trennung der Seltenen Erden ist möglich; Yttrium ist leichter eluierbar als die Lanthanide.
Summary The quantitative or nearly quantitative separation of the ion pairs Rb+/Cs+, K+/Rb+, k+/Cs+, Na+/K+ and Li+/Na+ can be achieved with hydrochloric acid or ammonium chloride solutions as eluents by means of columns of titanium hexacyanoferrate(II). The elution of the Cs+ ions is not possible. In the same way the quantitative or nearly quantitative separation of the ion pairs Sr2+/Ba2+, Ca2+/Ba2+, Ba2+/Cs+ and Sr2+/Cs+ can be achieved. Also a partial separation of the rare-earth elements is possible; yttrium is more easily eluted than the lanthanides.
  相似文献   

18.
The total energies of ZnO(1Σ), ZnO(3Π), ZnO?(2Σ), ZnO+(2Σ), ZnS(1Σ), ZnS(3Π), ZnS?(2Σ), and ZnS+(2Σ) were calculated ab initio by the CCSD(T) method with the use of atomic basis sets including 80, 84, and 93 functions for O, S, and Zn, respectively. Similar calculations were performed for the Zn atom [Zn(1 S), Zn(3 P), Zn+(2 S), Zn2+(1 S)] and several oxygen and sulfur states [O(3 P), O?(2 S), O(1 D), O2(3Σ), O 2 ? (2Π), O2(1Δ), S(3 P), S?(2 S), S(1 D), S2(3Σ), S 2 ? (2Π), and S2(1Δ)]. The ideology of engagement groups suggested by us is considered. According to this approach, data treatment can be performed on the assumption that the errors in all the 24 results obey the normal distribution law. As a result, we obtained D e(ZnO) = 1.70 ± 0.21 and D e(ZnS) = 1.57 ± 0.25 eV (at a 95% confidence level).  相似文献   

19.
The mixture of di- and monoethylene ketals obtained by the reaction of 1,9-dibromopentacyc lo[5.4.0.02,6.03,10.05,9]-undeca-8,11-dione followed by hydrolysis and ring contraction by Faworsky method was converted into a mixture of ethylene ketals of 7-bromopentacyclo[5.3.0.02,5.03,9.04,8]decan-6-one-4- and 5-bromopentacyclo[5.3.0.02,5.03,9.04,8]decan-6-one-8-carboxylic acid where the carboxy group was replaced by bromine along the procedure of Hunsdiecker-Borodine-Cristol. 6-Ethylene ketal of the pentacyclo[5.3.0.02,5.03,9.04,8] decan-6-one obtained by the debromination of ethylene ketals of 4,7- and 5,8-dibromopentacyclo[5.3.0.02,5.03,9.04,8] decan-6-one was hydrolyzed to ketone whose oxime was selectively reduced on a platinum catalyst into the di-6-pentacyclo[5.3.0.02,5.03,9.04,8]decylamine. The reaction of reductive dimerization was also characteristic of pentacyclo[4.3.0.02,5.03,8.04,7]-nonan-9-one and pentacyclo[6.3.0.02,6.03,10.05,9]undecan-4-one oximes, whereas the composition of the reduction products of pentacyclo[5.4.0.02,6.03,10.05,9]undecan-8-one oxime depended on the amount of the catalyst.  相似文献   

20.
《Analytical letters》2012,45(11):859-864
Abstract

The solubilities and Ksp values at 25°C for the following anion salts of nitron are reported: VO4 =, Cro4 =, Cr2O7 =,WO4 =, MoO4 =, BF4 ?, NO3 ?, NO2 ?, SeO3 =, S2O8 =, SCN?, Fe(CN)6 ?3, Fe(CN)6 ?4, Fe(CN)5NO=, I?, IO4 ?, CIO3 ?, CIO4 ?, BrO3 ?, and picrate?. A total of 58 anions were tested.  相似文献   

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