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1.
Hui Zhang Xianjin Yu Lei Chen Jiaqiang Geng 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(1):249-258
The sorption of 63Ni(II) from aqueous solution using ZSM-5 zeolite was investigated by batch technique under ambient conditions. ZSM-5 zeolite
was characterized by point of zero net proton charge (PZNPC) titration. The sorption was investigated as a function of shaking
time, pH, ionic strength, foreign ions, humic acid (HA), fulvic acid (FA) and temperature. The results indicate that the sorption
of 63Ni(II) on ZSM-5 zeolite is strongly dependent on pH. The sorption is dependent on ionic strength at low pH, but independent
of ionic strength at high pH values. The presence of HA/FA enhances 63Ni(II) sorption at low pH values, whereas reduces 63Ni(II) sorption at high pH values. The sorption isotherms are simulated by Langmuir model very well. The thermodynamic parameters
(i.e., ∆H
0, ∆S
0 and ∆G
0) for the sorption of 63Ni(II) are determined from the temperature dependent sorption isotherms at 293.15, 313.15 and 333.15 K, respectively, and
the results indicate that the sorption process of 63Ni(II) on ZSM-5 zeolite is spontaneous and endothermic. 相似文献
2.
Lipeng Zhang Hui Zhang Zhiwei Ge Xianjin Yu 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(2):537-546
The fate and transport of toxic metal ions and radionuclides in the environment is generally controlled by sorption reactions.
The removal of 60Co(II) from wastewaters by MnO2 was studied as a function of various environmental parameters such as shaking time, pH, ionic strength, foreign ions, and
humic substances under ambient conditions. The results indicated that the sorption of 60Co(II) on MnO2 was strongly dependent on pH and ionic strength. At low pH, the sorption of 60Co(II) was dominated by outer-sphere surface complexation and ion exchange with Na+/H+ on MnO2 surfaces, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. The presence of HA/FA enhances
60Co(II) sorption at low pH values, whereas reduces 60Co(II) sorption at high pH values. The Langmuir and Freundlich models were used to simulate the sorption isotherms of 60Co(II) at three different temperatures of 298.15, 318.15 and 338.15 K. The thermodynamic parameters (ΔH
0, ΔS
0 and ΔG
0) calculated from the temperature dependent sorption isotherms indicated that the sorption process of 60Co(II) on MnO2 was endothermic and spontaneous. 相似文献
3.
Liu Xia Chen Yuantao Chi Yaling Guo Zhijun Cai Linsen 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(3):1357-1366
In this article, a series of batch experiments were carried out to investigate the effect of various environmental factors
such as contact time, solid content, pH, ionic strength, foreign ions, temperature and coexisting humic acid on the sorption
behavior radionuclide 60Co(II) on illite. The results indicated that the sorption of Co(II) was strongly dependent on pH, ionic strength and temperature.
At low pH, the sorption was dominated by outer-sphere surface complexation and ion exchange on illite surfaces, whereas inner-sphere
surface complexation was the main sorption mechanism at high pH. The Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models
were used to simulate the sorption isotherms at three different temperatures of 303.15, 323.15 and 343.15 K. The thermodynamic
data (∆G
0, ∆S
0, ∆H
0) were calculated from the temperature dependent sorption isotherms and the results suggested that the sorption process of
Co(II) on illite was an endothermic and spontaneous process. The sorption test revealed that the illite can be as a cost-effective
adsorbent suitable for pre-concentration of Co(II) from large volumes of aqueous solutions. 相似文献
4.
Zhengjie Liu Jianwei Yang Zengchao Zhang Lei Chen Yunhui Dong 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(3):801-809
Bentonite was investigated to remove Ni(II) from aqueous solutions because of its strong sorption ability. Herein, bentonite
was modified with sodium carboxymethylcellulose (CMC) and used as an adsorbent to remove Ni(II) from aqueous solutions. The
results indicated that CMC-bentonite had higher sorption capacity than bare bentonite in the sorption of Ni(II) from aqueous
solutions. Sorption of Ni(II) on CMC-bentonite was mainly dominated by ion exchange or outer-sphere surface complexation at
low pH values, but by inner-sphere surface complexation or surface precipitation at high pH values. The thermodynamic data
calculated from temperature dependent sorption isotherms indicated that the sorption of Ni(II) to CMC-bentonite hybrids was
an spontaneous process and enhanced with increasing temperature. 相似文献
5.
6.
R. Adam Rebeles P. Van den Winkel A. Hermanne L. De Vis R. Waegeneer 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(3):655-659
A homemade modular PC-controlled radiochemistry system, used to separate the no-carrier-added 64Cu from irradiated electroplated solid cyclotron target 64Ni layers was developed. Upon irradiation the target layer is dissolved in diluted nitric acid, followed by selective liquid–liquid
extraction of the 64Cu. The final purification step is achieved making use of an anion exchange column. All the separation procedures can be carried
out remote-controlled with a minimized risk of operator errors within less than 2 h, with excellent processing yield (>95%). 相似文献
7.
The sorption of Pb(II) from aqueous solution using NKF-5 zeolite was investigated by batch technique under ambient conditions.
The NKF-5 zeolite sample was characterized by using FTIR and X-ray powder diffraction in detail. The sorption of Pb(II) was
investigated as a function of pH, ionic strength, foreign ions, and humic substances. The results indicated that the sorption
of Pb(II) on NKF-5 zeolite was strongly dependent on pH. The sorption was dependent on ionic strength at low pH, but independent
of ionic strength at high pH. At low pH, the sorption of Pb(II) was dominated by outer-sphere surface complexation and ion
exchange with H+ on NKF-5 zeolite surfaces, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. From the
experimental results, one can conclude that NKF-5 zeolite has good potentialities for cost-effective preconcentration of Pb(II)
from large volumes of aqueous solutions. 相似文献
8.
A. R. Jalilian L. Mirsadeghi Y. Yari-kamrani P. Rowshanfarzad M. Kamali-dehghan M. Sabet 《Journal of Radioanalytical and Nuclear Chemistry》2007,274(3):563-568
Copper-64 was produced as a by-product of 55Co via 64Ni(p,n)64Cu by 15 MeV proton bombardment of natNi resulting in a thick target yield of 5.31 MBq/μAh (143.5 μCi/μAh) and a radiochemical separation yield of 95% (radionuclide
purity >97% after 25 hours of bombardment). Rituximab was successively labeled with [64Cu]-CuCl2. N-succinimidyl-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA-NHS) was prepared at 25 °C using DOTA and
N-hydroxy succinimide (NHS) in CH2Cl2 followed by the addition of 1 ml of a Rituximab pharmaceutical solution. Radiolabeling was performed at 37 °C in 3 hours.
Radio thin-layer chromatography showed an overall radiochemical purity of 90–95% at optimized conditions (specific activity=30
GBq/mg, labeling efficacy; 82%) using various chromatography systems. The final isotonic 64Cu-DOTA-Rituximab complex was passed through a 0.22 μm filter and checked by gel electrophoresis for radiolysis control. Stability
of the final product was checked in the formulation and in presence of human serum at 37 °C. 相似文献
9.
Le Van So P. Pellegrini A. Katsifis J. Howse I. Greguric 《Journal of Radioanalytical and Nuclear Chemistry》2008,277(2):451-466
The radiochemical separation of the different radionuclides (64Cu, 67Cu, 67Ga, 66Ga, 56Ni, 57Ni, 55Co, 56Co, 57Co, 65Zn, 196Au) induced in the Ni supported Cu substrate — 68Zn target system, which was bombarded with the 29.0 MeV proton beam, was performed by ion-exchange chromatography using successive
isocratic and/or concentration gradient elution techniques. The overlapped gamma-ray spectrum analysis method was developed
to assess the 67Ga and 67Cu content in the 64Cu product and even in the post-67Ga production 68Zn target solution without the support of radiochemical separation. This method was used for the assessment of 64+67Cu radioisotope separation from 67Ga, the quality control of 64Cu product and the determination of the 68Zn (p,2p)67Cu reaction yield. The improvement in the targetry and the optimization of proton beam energy for the 68Zn target based 64Cu and 67Ga production were proposed based on the stopping power and range of the incident proton and on the excitation functions,
reaction yields and different radionuclides induced in the target system. 相似文献
10.
Zhiqiang Guo Donglin Zhao Yuan Li Zhesheng Chen Haihong Niu Jinzhang Xu 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(3):829-837
The sorption of radiocadmium on Ca-montmorillonite as a function of contact time, pH, ionic strength, foreign ions, humic acid (HA) and fulvic acid (FA) was studied using batch technique. The results demonstrated that the sorption of Cd(II) was dependent on ionic strength at pH < 9, and was independent of ionic strength at pH > 9. Outer-sphere surface complexation and/or ion exchange were the main mechanism of Cd(II) sorption on Ca-montmorillonite at low pH, whereas the sorption at high pH was mainly dominated via inner-sphere surface complexation. The sorption of Cd(II) on Ca-montmorillonite was dependent on foreign ions at low pH values, but was independent of foreign ions at high pH values. A positive effect of HA/FA on Cd(II) sorption was found at low pH values, whereas a negative effect was observed at high pH values. The thermodynamic parameters (i.e., ??H 0, ??S 0, ??G 0) were calculated from the temperature dependent sorption isotherms, and the results indicated that the sorption process of Cd(II) on Ca-montmorillonite was spontaneous and endothermic. 相似文献
11.
P. Rajec V. Csiba M. Leporis M. Štefečka E. Losonczi Pataky M. Reich J. Ometáková 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(3):665-670
The reaction route 64Ni(p,n)64Cu is very popular for the preparation of 64Cu because its entrance channel is accessible at low energies and yield of reaction is quite high. However, a high price of
the enriched 64Ni is a disadvantage of this reaction path; hence, preparation of a chemically pure nickel targets for the production of 64Cu using COSTIS (Compact Solid Target Irradiation System) is of a great research interest. In this paper, effects of boric
acid, composition of electrolytic bath and electrochemical process conditions on the quality of nickel films deposited on
2 mm thick gold or platinum disc targets were investigated. Chemical purity of the electrodeposited nickel was measured by
the Auger electron spectroscopy and the surface quality of targets was studied microscopically (SEM). A SRIM program was used
for a thickness target calculation. COSTIS target station was installed at the end of the external beam line of the IBA Cyclone
18/9 cyclotron, and the irradiation surface of target was optimized. The target station has been equipped with Al or Nb window
foil in the front of the target to degrade the beam energy to an optimal value. 相似文献
12.
C. Dirks B. Scholten S. Happel A. Zulauf A. Bombard H. Jungclas 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(3):671-674
Cu isotopes (e.g. 64Cu) increasingly find use in radiopharmaceutical applications, accordingly fast and reliable methods for the production of
these isotopes are needed. The aim of the presented project is the characterization of a Cu selective extraction chromatographic
resin for the fast and selective separation of Cu radionuclides, e.g. from irradiated targets. The characterisation of the
resin includes the determination of weight distribution factors D
w
of Cu, Ni, Zn and other potentially interfering elements and impurities for varying acids and pH values, the influence of
macro amounts of Ni and Zn on the extraction of Cu as well as the influence of other potential interferents. Based on the
obtained results, a method for the separation of Cu and its purification from irradiated Ni or Zn targets was developed and
tested on simulated Ni and Zn targets. 相似文献
13.
H. M. H. Gad H. A. Elsanafini M. M. S. Ali Y. F. Lasheen M. G. Abdelwahed 《Russian Journal of Applied Chemistry》2016,89(6):988-999
In this study, saw dust has been used as precursor for production of low cost activated carbon using potassium hydroxide (KOH) and steam activation technique. The activated carbon was used to remove Cs+ and Sr2+ ions from aqueous solutions by batch operation, and the extent of adsorption was investigated as a function of solution pH, temperature, shaking time, and initial concentration. The influence of interfering ions was also investigated. The removal of metal ions was pH dependent and the adsorption capacity reaches its maximum 43% and 61.5% at pH 5.0 and 6.0 for Cs+ and Sr2+ ions, respectively. Thermodynamic studies showed different behaviours where an endothermic, non-spontaneous process was shown for Cs+ while an exothermic, spontaneous process was obtained for Sr2+. The kinetic data of both ions was described well by pseudo-second order rate equation. The two equilibrium models (Langmuir and Freundlich) have been also applied. Desorption studies indicated that HCl was the most effective desorbing eluent. The investigated adsorbent showed good results towards cesium and strontium removal from aqueous media that could be a promising method due to its low-cost and good efficiency. 相似文献
14.
G. I. Smirnov L. M. Dimova A. A. Redchenko 《Russian Journal of Applied Chemistry》2004,77(8):1259-1262
Ion-exchange sorption of K+ and Na+ from their mixture on X-ray-amorphous and crystalline Sn(IV) hydrophosphates was studied. These sorbents exhibit a high selectivity for K+. Amorphous Sn(IV) hydrophosphate can be used for efficient purification of aqueous sodium salt solutions to remove potassium impurity.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 8, 2004, pp. 1275–1278.Original Russian Text Copyright © 2004 by Smirnov, Dimova, Redchenko. 相似文献
15.
Tanveer Hussain Bokhari A. Mushtaq Islam Ullah Khan 《Journal of Radioanalytical and Nuclear Chemistry》2010,284(2):265-271
Production of radioactive scandium by irradiating natural titanium metal in Pakistan Research Reactor-1 was evaluated. The
production rate of 47Sc and other radioactive scandium was estimated. High specific activity 47Sc can be produced by irradiating enriched 47Ti in sufficient quantities needed for therapeutic applications. A new separation technique based on column chromatography
was developed. Neutron irradiated titanium was dissolved in hydrofluoric acid, which was evaporated and taken in distilled
water. The resulting solution was loaded on silica gel column. The radioactive scandium comes out first and the inactive titanium
is removed with 2 M HCl. More than 95% radioactive scandium was recovered, while chemical impurity of titanium determined
by optical emission spectroscopy was less than 0.01 μg/mL in final product. 相似文献
16.
Lipeng Zhang Xianjin Yu Hui Zhang Enze Chen Tao Dong 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):1473-1485
In this work, a naturally occurring illite was characterized by using FT-IR and XRD technique to determine its surface functional groups and crystal structure. Sorption of 60Co(II) on illite as a function of contact time, pH, ionic strength, foreign ions, humic substances and temperature was studied under ambient condition using batch technique. The results indicated that the sorption of 60Co(II) on illite is strongly affected by pH values (2–9) and ionic strength. A positive effect of humic substances on 60Co(II) sorption was found at pH < 7.0, whereas a negative effect was observed at pH > 7.0. At low pH, the sorption of 60Co(II) was dominated by outer-sphere surface complexation and ion exchange with Na+/H+ on illite surfaces, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. The Langmuir and Freundlich models were used to simulate the sorption isotherms of 60Co(II) at three different temperatures of 298.15, 323.15 and 343.15 K. The thermodynamic parameters (ΔH 0, ΔS 0 and ΔG 0) calculated from the temperature dependent sorption isotherms indicated that the sorption process of 60Co(II) on illite was endothermic and spontaneous. 相似文献
17.
G. D. Kim H. J. Woo H. W. Choi N. B. Kim T. K. Yang J. H. Chang K. S. Park 《Journal of Radioanalytical and Nuclear Chemistry》2007,271(3):553-558
Neutron capture cross sections on 63Cu and 186W were measured by fast neutron activation method at neutron energies from 1 to 2 MeV. Monoenergetic fast neutrons were produced
by 3H(p,n)3He reaction. Neutron energy spread by target thickness, which was assumed to be the main factor of neutron energy spread,
was estimated to be 1.5% at neutron energy of 2.077 MeV. Neutron capture cross sections on 63Cu and 186W were calculated by reference comparison method on those of 197Au(n,γ). Not only statistical errors of gamma-counts from samples but also systematic errors in the counting efficiency for
HP Ge detector and the uncertainty of areal density of samples were considered in calculating neutron capture cross section.
Estimated neutron capture cross sections on 63Cu and 186W were also compared with ENDF-6 data. 相似文献
18.
E. S. Zakaria 《Journal of Radioanalytical and Nuclear Chemistry》2005,264(3):629-635
Summary This paper reports the radiochemical study of the ion-exchange of Cs+, Na+, Sr2+ and Eu3+ ions with H+ by chromium hexacyanoferrate(II) which was prepared in a granular form using a gel method. The slow steps which determine the rate of exchange of these ions are directly proportional to the particle diameter and this is confirmed from the linearity test of Bt vs. t plots at different particle diameters. Boyed’s equation and Reichenberg’s tables were used for evaluating all the kinetic parameters. The results reveal that the effective particle radii are unchanged for both chromium hexacyanoferrate(II) dried at 60 and 120 °C. The obtained data were analyzed using McKay plots and Arrhenius equation and the kinetic and thermodynamic parameters, e.g., effective diffusion coefficient, activation energies and entropies of activation have been evaluated. The mobility of these ions inside the particles of chromium hexacyanoferrate(II) decrease in the order of Eu3+>Sr2+>Na+⊃Cs+. 相似文献
19.
20.
A. V. Ivanov E. V. Korneeva B. V. Bukvetskii A. S. Goryan O. N. Antzutkin W. Forsling 《Russian Journal of Coordination Chemistry》2008,34(1):59-69
The structures and spectroscopic properties of mononuclear and binuclear mercury(II) and copper(II) complexes with four dithiocarbamate ligands R2NC(S)S? (R = CH3, C2H5, or iso-C3H7; R2 = (CH2)6) were studied by solid-state 13C and 15N CP/MAS NMR and EPR spectroscopy. Mercury(II) N,N-cyclohexamethylenedithiocarbamate [Hg2{S2CN(CH2)6}4] was obtained and characterized in detail by X-ray diffraction analysis at 299 K. The binuclear molecule of the complex is centrosymmetric; the central tricyclic fragment [Hg2S4C2] is in the chair conformation. In the 13C and 15N NMR spectra, the signals were assigned to the dithiocarbamate ligands with different structural functions: bidentate chelating and combined (both chelating and bridging) ones. The differences between the isotropic 15N chemical shifts for the dialkyldithiocarbamate ligands were interpreted in terms of combination of the mesomeric effect of the =NC(S)S-groups and the inductive effect of the alkyl substituents. According to the EPR data, copper(II) in magnetically diluted systems is mainly found in heterobinuclear molecules [CuHg(S2CNR2)4] and the geometry of the chromophores [CuS5] approximates to a tetragonal pyramid. 相似文献