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1.
The activated carbon was prepared by using corncobs and characterized by sorpatometer for using as an exchanger material to separate the generated 113mIn from 113Sn and 124,125Sb. To optimize the separation process, the different parameters like acetone percentage, HCl concentration were studied. The exchange capacity of Sn(IV) is 7.6 meq/g onto the activated carbon and the elution efficiency of 113mIn > 80% by using 10 mL of 0.2 M HCl-80% acetone with flow rate 1 mL/min. The radionuclidic purity and radiochemical purity of the eluted 113mIn were examined and clarified the presence of 124,125Sb with relatively high level as radio impurities, so further separation was carried out by using Dowex 1×8 as an anion exchanger below the activated carbon matrix on the same separation column to adsorb the 113Sn and 124,125Sb, which escape from the activated carbon matrix.  相似文献   

2.
A procedure for preparation of 99Mo/99mTc radioisotope generator based on low specific activity neutron activated 99Mo was developed. Aluminum molybdate(VI)-99Mo of high Mo(VI) content (~?364 mg/g Al99Mo) was prepared by mixing low specific activity molybdate(VI)-99Mo and aluminum mixture solution with isoamyl alcohol. Al99Mo gel matrix was precipitated when the pH of the mixture solution was raised to ~?5 by addition of NaOH to the mixture. Radiometric measurements indicate the strong fixation of Molybdate(VI)-99Mo species in the form of the sparingly insoluble Al99Mo gel matrix. The prepared AlMo gel matrix was physiochemically characterized. Al99Mo gel matrix was used as a base material for preparation of 99Mo/99mTc generator. The 99mTc eluted from 99Mo/99mTc radioisotope generator was found to have relatively high elution yield (84?±?2.3%), radionuclidic (≥?99.99%), radiochemical (98.1?±?0.9%) and chemical purity.  相似文献   

3.
A procedure for separation of no-carrier-added 113mIn(III) radioisotope from a bulk of 110mAg has been developed. The sorption behavior of 113mIn(III) and 110mAg(I) ions in HNO3 acid solutions on different tungstocerate matrices showed high affinity of 110mAg(I) ions towards tungstocerate(IV) gel matrices compared with 113mIn(III) ions. No-carrier-added 113mIn radionuclide was separated from 110mAg on 12-tungstocerate(IV) column matrix. 11 mL 0.3M HNO3 acid solution was enough for eluting the 113mIn from the column bed. 110mAg was recovered from the column by eluting the column bed with 12 mL 2M HNO3 acid solution.  相似文献   

4.
Radiolabeled fatty acids as myocardial metabolic agent are used for detecting ischemic heart disease, however, no 99mTc-labeled fatty acids have potential use in clinical diagnosis. In this work, five fatty acid analogues labeled with 99mTc were firstly synthesized and characterized, their biological behaviors were investigated. All Radiotracers had good stability when incubated in rat serum for 3 h at 37 °C. 99mTc -CpT-12-ODPPA (8b) showed higher initial myocardial uptake (8.17% ID/g at 1 min postinjection) and good heart/blood ratio (2.58 at 30 min postinjection). 99mTc-11-dpa-OUFA (2b) as positively charged lipophilic compounds had reasonable heart uptake (5.59% ID/g at 1 min postinjection) and good retention (1.89% ID/g at 60 min postinjection). Unfortunately, no great improvement was obtained by the five 99mTc-labeled fatty acid analogues for the short myocardial retention and poor heart/liver ratios.  相似文献   

5.
The authors describe a cataluminescence (CTL) based sensing method via signals generated at the surface of In3LaTi2O10 nanoparticles for simultaneous determination of trimethylamine, formaldehyde and benzene in air. The analytical wavelengths are 340 nm, 440 nm and 600 nm, and the best surface temperature of the catalytic material is 275 °C. The limits of detection of this method are 0.3 mg?m?3 for trimethylamine, 0.07 mg?m?3 for formaldehyde, and 0.2 mg?m?3 for benzene. The linear ranges of CTL intensity versus gas/vapor concentration are from 1.0 to 65.1 mg?m?3 for trimethylamine, from 0.2 to 72.5 mg?m?3 for formaldehyde, and from 0.5 to 77.5 mg?m?3 for benzene. The recoveries after testing 10 standard samples ranged from 98.1% to 102.6% for trimethylamine, from 98.1% to 102.6% for formaldehyde, and from 97.7% to 103.8% for benzene. Gaseous ammonia, acetaldehyde, toluene, ethylbenzene, ethanol, sulfur dioxide and carbon dioxide do not interfere. The relative deviation of the CTL signals after 200 h of continuous detection of trimethylamine, formaldehyde and benzene is <3%.
Graphical abstract Schematic of a cataluminescence (CTL) based method for simultaneous determination of trimethylamine (TMA), formaldehyde (HCHO) and benzene (C6H6) in air. The linear ranges of CTL intensity versus gas/vapor concentration are from 1.0 to 65.1 mg?m?3 for TMA, from 0.2 to 72.5 mg?m?3 for HCHO, and from 0.5 to 77.5 mg?m?3 for C6H6.
  相似文献   

6.
This paper is focused on a characterization of bacterial contamination in pool water of the interim spent fuel storage (JAVYS Inc.) in Slovak Republic and on bioaccumulation of 137Cs and 60Co by isolated bacteria. Bacterial community in pool water is kept on very low level by extremely low concentration of solutes in deionized water and by the efficient water filtration system. Based on standard methods and sequencing of 16S rDNA four pure bacterial cultures were identified as Kocuria palustris, Micrococcus luteus, Ochrobactrum spp. and Pseudomonas aeruginosa. Isolated aerobic bacteria were able to bioaccumulate 137Cs and 60Co in laboratory experiments. The mechanism of Co and Cs binding involve rapid interactions with anionic groups of the components of cell surface and in the case of Cs+ ions is followed by transport processes across cytoplasm membranes and by intracellular distribution. The maximum specific uptake of Cs+ after 48 h cultivation in mineral medium (MM) reached 7.54 ± 0.48 μmol g?1 dw (Ochrobactrum spp.), 19.6 ± 0.1 μmol g?1 dw (M. luteus) and 20.1 ± 2.2 μmol g?1 dw (K. palustris). The maximum specific uptake of Co2+ after 24 h cultivation in MM reached 31.1 ± 3.5 μmol g?1 dw (Ochrobactrum spp.), 86.6 ± 12.2 μmol g?1 dw (M. luteus) and 16.9 ± 1.2 μmol g?1 dw (K. palustris). These results suggest that due to the long lasting uptake of 137Cs, 60Co and other radionuclides by biofilm in pool water high specific radioactivities (Bq m?2) can be expected on stainless steel walls of pools.  相似文献   

7.
The preparation of a carbon ceramic electrode modified with SnO2 (CCE/SnO2) using tin dibutyl diacetate as precursor was optimized by a 23 factorial design. The factors analyzed were catalyst (HCl), graphite/organic precursor ratio, and inorganic precursor (dibutyltin diacetate). The statistical treatment of the data showed that only the second-order interaction effect, catalyst × inorganic precursor, was significant at 95% confidence level, for the electrochemical response of the system. The obtained material was characterized by scanning electron microscopy (MEV), X-ray diffraction (XRD), RAMAN spectroscopy, XPS spectra, and voltammetric techniques. From the XPS spectra, it was confirmed the formation of the Si–O–Sn bond by the shift in the binding energy values referred to Sn 3d3/2 due to the interaction of Sn with SiOH species. The incorporation of SnO2 provided an increment of the electrode response for levofloxacin, with Ipa = 147.0 μA for the ECC and Ipa = 228.8 μA for ECC/SnO2, indicating that SnO2 when incorporated into the silica network enhances the electron transfer process. Under the optimized working conditions, the peak current increased linearly with the levofloxacin concentration in the range from 6.21×10?5 to 6.97×10?4 mol L?1 with quantification and detection limits of 3.80×10?5 mol L?1 (14.07 mg L?1) and 1.13×10?5 mol L?1 (4.18 mg L?1), respectively.  相似文献   

8.
A novel quinoline derivative, 2,2′-[(5-chloro-8-hydroxyquinoline-7-yl) methylazanediyl] diacetic acid (CHQMADA) was labeled with 99mTc using SnCl2·2H2O as a reducing agent to give a complex with a labeling yield 94 %. Also [99mTc(H2O)3(CO)3]+ was prepared by heating at 100 °C for 30 min using 2 mg CHQMADA at pH 8 to give a labeling yield >99 %. 99mTc-(CO)3 CHQMADA and 99mTc-Sn(II)-CHQMADA showed tissue uptake (target to non target T/NT = 6.80 ± 0.22) and (T/NT = 5.65 ± 0.34) respectively in Escherichia coli induced infection, which is higher than the commercially available 99mTc-ciprofloxacin (T/NT = 3.80 ± 0.80). In conclusion, both complexes were able to differentiate between septic and aseptic inflammation with superiority of [99mTc-(CO)3 CHQMADA].  相似文献   

9.
LiNi0.80Co0.15Al0.05O2 (NCA) is explored to be applied in a hybrid Li+/Na+ battery for the first time. The cell is constructed with NCA as the positive electrode, sodium metal as the negative electrode, and 1 M NaClO4 solution as the electrolyte. It is found that during electrochemical cycling both Na+ and Li+ ions are reversibly intercalated into/de-intercalated from NCA crystal lattice. The detailed electrochemical process is systematically investigated by inductively coupled plasma-optical emission spectrometry, ex situ X-ray diffraction, scanning electron microscopy, cyclic voltammetry, galvanostatic cycling, and electrochemical impedance spectroscopy. The NCA cathode can deliver initially a high capacity up to 174 mAh g?1 and 95% coulombic efficiency under 0.1 C (1 C?=?120 mA g?1) current rate between 1.5–4.1 V. It also shows excellent rate capability that reaches 92 mAh g?1 at 10 C. Furthermore, this hybrid battery displays superior long-term cycle life with a capacity retention of 81% after 300 cycles in the voltage range from 2.0 to 4.0 V, offering a promising application in energy storage.  相似文献   

10.
A method for production of no-carrier-added 117mSn (NCA 117mSn) has been developed. It includes proton irradiation of thick antimony targets and chemical recovery of 117mSn by extraction of Sb with dibutyl ether and chromatographic purification on silica gel column. The method provides production of curie amounts of 117mSn with specific activity about 1000 Ci/g and high radionuclidic purity.  相似文献   

11.
The hydrolytic species of lanthanide ions, La3+ and Sm3+, in water at I = 0.1 mol·dm?3 KCl ionic strength and temperatures of 298.15, 310.15 and 318.15 K were investigated by potentiometry. The hydrolytic species were modeled by the HySS simulation program. From the results, the hydrolytic species of each metal ion at different temperatures were calculated using the program HYPERQUAD2013. The hydrolysis constants (log10 β) of [La(OH)]2+ and La(OH)3 were calculated as ?8.52 ± 0.46, ?26.84 ± 0.48, and log10 β values of [Sm(OH)]2+, [Sm(OH)2]+, Sm(OH)3 were calculated as ?7.11 ± 0.21, ?15.84 ± 0.25 and ?23.44 ± 0.52 in aqueous media at 298.15 K, respectively. The dependence of the hydrolysis constants on the temperature allowed us to calculate the enthalpy, entropy, and Gibbs energy of hydrolysis values of each species.  相似文献   

12.
A novel 1,8-naphthalimide dye with simple structure has been produced by a facile synthetic method for colorimetric and fluorescent sensing of H+ and Cu2+. In CH3CN/H2O (1/1, v/v), the dye could monitor H+ using dual channels (ratiometric absorbance and fluorescence intensity change) from pH 6.2 to 12.0. Meanwhile, in the pH range of 1.9–5.2, the dye could also be used to detect Cu2+ using triple channels [ultraviolet–visible (UV–Vis) absorption, fluorescence intensity reduction, as well as fluorescence blueshift]. The detection limits for Cu2+ evaluated by colorimetric and fluorescent titration were 6.10 × 10?7 and 2.62 × 10?7 M, respectively. The dye exhibited specific selectivity and sensitivity for H+ and Cu2+ over various coexisting metal ions. Moreover, the sensing mechanism of the dye for H+ and Cu2+ was carefully examined.  相似文献   

13.
The radioisotope 117mSn has recently attracted considerable attention because of its application in theranostics and its imaging using 159-keV γ-photons. In this study, we developed a target system that yielded 117mSn via a 116Cd(α, 3n)117mSn nuclear reaction. A separable Pt substrate was utilized to prepare the enriched 116Cd target to be irradiated, and the enriched 116Cd in a cadmium acetate solution was electroplated onto the Pt substrate. The substrate was thermally analyzed via ANSYS simulations, and the plating thickness was optimized through calculations with TALYS code. The production of 117mSn was confirmed through the emission measurement of inherent gamma rays.  相似文献   

14.
The Li(Ni0.33Co0.33Mn0.33)O2 (LNCMO) cathode material is prepared by poly(vinyl pyrrolidone) (PVP)-assisted sol-gel/hydrothermal and poly(ethylene glycol)-block-poly(propylene glycol)-block-poly (ethylene glycol) (Pluronic-P123)-assisted hydrothermal methods. The compound prepared by PVP-assisted hydrothermal method shows a comparatively higher electrical conductivity of ~2?×?10?5 S cm?1 and exhibits a discharge capacity of 152 mAh g?1 in the voltage range of 2.5 to 4.4 V, for a C-rate of 0.2 C, whereas the compounds prepared by P123-assisted hydrothermal method and PVP-assisted sol-gel method show a total electrical conductivity in the order of 10?6 S cm?1 and result in poor electrochemical performance. The structural and electrical properties of LNCMO (active material) and its electrochemical performance are correlated. The difference in percentage of ionic and electronic conductivity contribution to the total electrical conductivity is compared by transference number studies. The cation disorder is found to be the limiting factor for the lithium ion diffusion as determined from ionic conductivity values.  相似文献   

15.
The adsorption characteristics of 113Sn(IV) and 113mIn(III) on glass beads from NaCl solutions have been studied. On the basis of these studies, 113Sn-113mIn generator has been prepared by adsorbing 113Sn on the glass beads column. 113mIn has been eluted by the 0.16M NaCl solution with pH 3.0, remaining 113Sn adsorbed on the glass beads. The yield of 113mIn has been about 73% in the first 6 ml of eluate, while the breakthrough of 113Sn has been about 0.042%.  相似文献   

16.
Possibility of using a low-temperature magnesium-potassium phosphate matrix to solve the problem of immobilizing the radioactive wastes containing radioactive carbon (14C) in the form of calcium carbonate was examined. The physicochemical characteristics of the compounds obtained were determined. Large values of the ultimate compression strength (22 ± 5 MPa), which satisfy the technical requirements for cemented radioactive wastes (no less than 4.9 MPa), were obtained. The minimum carryover of carbon dioxide into the atmosphere in the course of synthesis and in keeping of samples for 14 days was noted: not more than 3 wt % relative to the starting CaCO3. The leaching rate of carbonate ions from magnesium-potassium compounds by 28th day of contact with air does not exceed 10?9 g cm?2 day?1, with this value for the rest of the compound components not exceeding 10?4 g cm?2 day?1. Thus, it was found that the magnesium?potassium phosphate matrix is an alternative to the cementation for solidification of radioactive wastes containing 14C.  相似文献   

17.
This article reports the selective sensing ability of a newly synthesized calix[4]arene Schiff base (C4TSB) derivative. C4TSB exhibited strong turn-off fluorescence affinity for Hg2+ and Au3+. The selective sensing ability of receptor was investigated in the presence of different co-existing competing ions. The limit of detection for Hg2+ and Au3+ was determined as 1.9 × 10?5 and 1.0 × 10?6 M, respectively. Receptor forms 1:1 stoichiometric complex with both metals and their binding constants were calculated as 7.9 × 103 M?1 for Hg2+ and 5.7 × 103 M?1 for Au3+. Complexes were also characterized through FT-IR spectroscopy.  相似文献   

18.
Surface soil samples collected in the Jiuquan region in the downwind area of the Chinese nuclear test site (CNTs) were analyzed for Pu isotopes. The 239+240Pu activities ranged from 0.025 ± 0.009 to 0.89 ± 0.16 mBq g?1, varying significantly with different sampling sites. The Dunhuang city that is located in the southwestern part of the Jiuquan region received the heaviest Pu deposition (239+240Pu activities, 0.23–0.89 mBq g?1). Most of the 240Pu/239Pu isotopic ratios were similar with that of the global fallout. However, the low values (0.080–0.147) observed in three sampling sites further supported the finding of Pu originated from CNTs in that region.  相似文献   

19.
90Y was separated from 90Sr using an extraction chromatographic resin consisting of 4, 4′(5′)-bis-t-butylcyclohexano-18-crown-6 (DtBuCH18C6), 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl) amide (C2mimNTf2), and a polymer (Amberlite XAD-7). Ionic liquid was introduced into the column to improve the separation efficiency. The column showed an excellent performance for the separation of Y from Sr. After the separation, the ratio of 90Sr/90Y was <2.0 × 10?5; the column was recycled for >18 times. This study provides preliminary results on columns to produce 90Y with a high purity in radiopharmaceuticals.  相似文献   

20.
The indoor 222Rn radionuclide was directly absorbed in typical 20 ml glass scintillation vials by passing ?3 dm3 of ambient air through 16 ml of water-immiscible non-volataile scintillation cocktail Ultima-Gold F for 10 min. The activity of radon and its two α-emitting daughters: 218Po and 214Po, was determined with the BetaScout low-background liquid scintillation counter. The limit of 222Rn detection is 9 Bq/m3, and the quantification limit with 20% relative accuracy is 28 Bq/m3. The results of the indoor Rn measurement in different houses showed good consistency with results obtained from a Sarad EQF 3220 device.  相似文献   

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