共查询到20条相似文献,搜索用时 15 毫秒
1.
Haider A. Khwaja Adil R. Khan Sumizah Qureshi 《International journal of environmental analytical chemistry》2013,93(3):285-297
Abstract The use of ion-exchange chromatography with an IonPac AS 14 column, 3.5 mM Na2CO3/1.0 mM NaHCO3 eluent and suppressed conductivity detection provides a simple, cost-effective, fast, accurate, and highly sensitive method for the determination of F?, Cl?, NO2 ?, Br?, NO3 ?, PO4 2?, SO4 2?, and C2O4 2? at low μ/L levels in environmental samples. Data on sensitivity, selectivity, accuracy, and % relative standard deviation are described. The method is suitable for many environmental applications including atmospheric aerosols (exposed on cellulose, glass fiber, and quartz filters), rainwater, cloud water, potable- and non-potable waters, and carbonated waters. Dominant components of the aerosol were SO4 2?, NO3 ?, and Cl?. Rainwater, on the other hand, has relatively very low concentrations of these three species. The wide-spread concentration range for Cl? in variety of water samples and the high concentrations for SO4 2? in drinking water are striking. Determination of the anionic composition of carbonated waters revealed a considerable variation of the individual anions. 相似文献
2.
Dioctylarsinic acid, HDOAA, in chloroform (0.1 M) extracts thulium(III), dysprosium(III) and samarium(III) from their aqueous solutions in the pH ranges 1–6.5, 2–7 and 4–8, respectively, with extraction coefficients of approximately 0.1 for the lowest and 10 for the highest pH. The extractability increased with increasing ionic strength for each ion and decreased in the order ClO4- > NO3- > Cl- > SO42- > acetate for solutions of the same molarity. pH-Dependence curves had slopes ranging from 1.05 to 1.87. The reagent-dependence studies gave curves with slopes between 3.60 and 5.30. The general formula [MXn(DOAA)m(HDOAA)p(H2O)q] (X = Cl-. NO3-, SO42-/2, ClO4-, acetate, OH-; n+m=3, m+p=4 or 5, q?0)is suggested for the extracted species. 相似文献
3.
C. Noubactep 《Journal of Radioanalytical and Nuclear Chemistry》2005,267(1):13-19
Summary Theeffect ofCl-, CO32-, EDTA, NO2-, NO3-, PO43-, SO42-, and humic substances (HS)on the U(VI)co-precipitation from aqueous solutions by zerovalent iron (ZVI) was investigated in
the neutral pH range.Batch experiments without shaking were conducted for 14 days mostly with five different ZVI materials
(15 g/l), selected ligands (10mM) and an U(VI) solution (20 mg/l, 0.084mM). Apart from Cl-, all tested ligands induced a decrease ofU(VI)coprecipitation. This decrease is attributed to the surface adsorption and
complexation of the ligands at the reactive sites on the surface of ZVI and their corrosion products. The decrease ofU(VI)removal
was not uniform with the five ZVI materials. Generally, groundwater with elevated EDTA concentration could not be remediated
with the ZVI barrier technology. The response of the system on the pre-treating by two ZVI materials in 250mM HCl indicated
that in situ generated corrosion products favor an irreversible U(VI) uptake. Thus for the long term performance of ZVI barrier,
the iron dissolution should continue in such a way that fresh iron oxide be always available for U(VI) coprecipitation. 相似文献
4.
A film polyvinyl chloride (33 wt %) carbonate-selective electrode based on a higher quaternary ammonium salt with increased steric accessibility of the exchange site, 3,4,5-tris(dodecyloxy)benzyl( oxyethyl)3trimethylammonium chloride (5 wt %), was developed using o-nitrophenyl decyl ether (52 wt %) as a plasticizer and heptyl p-trifluoroacetylbenzoate (10 wt %) as a solvating agent. The limit of detection of hydrocarbonate was 1.9 × 10?9 M, lifetime was 2.5 months, and the slope of the electrode function was 32.3 ± 0.6 mV/decade. The electrode is selective in the presence of interfering SO42-, Cl?, C2O42-, Br?, HPO42-, and NO3- ions, which allows its application for the determination of HCO3- ions in mineral water. 相似文献
5.
In this study a cobalt film electrodeposited on a copper disk (Ø=3.1 mm) was tested as electrode to measure nitrite ions in raw water. This electrode was able to determine the nitrite ions concentration in nondeaerated synthetic media and in natural water. The electrode reached a detection limit of 0.2 μmol L?1 and has a linear concentration range of 0.4 to 2 μmol L?1 NO2?. The influence of several ions such as NO3?, Cl?, SO42?, Mg2+, HCO3? and NH4+ was also tested. The electrode was used to determine the concentration of nitrite ions in a real sample. 相似文献
6.
Sviderskii V. A. Voronkov M. G. Klimenko S. V. Bystrov D. N. 《Russian Journal of Applied Chemistry》2001,74(12):2087-2090
The structure and composition of polyheterosiloxanes formed in hydrolytic polycondensation of ethyl silicate in the presence of copper salts under the conditions of base catalysis (NH4OH) were studied as influenced by the nature of acid anion (SO4
2
-, Cl-, NO3
-, CH3COO-). 相似文献
7.
Kemilly M. P. Pinheiro Roger C. Moreira Kariolanda C. A. Rezende Mrcio Talhavini Lucio P. L. Logrado Jos A. F. Baio Marcos R. V. Lanza Wendell K. T. Coltro 《Electrophoresis》2019,40(3):462-468
This study describes the development of an analytical methodology based on the use of microchip electrophoresis (ME) devices integrated with capacitively coupled contactless conductivity detection (C4D) for the separation and detection of inorganic anions in post‐blast explosive residues. The best separation condition was achieved using a running buffer composed of 35 mmol/L lactic acid, 10 mmol/L histidine and 0.070 mmol/L cetyl(trimethyl ammonium) bromide. For C4D measurements, the highest sensitivity was obtained applying a 700 kHz sinusoidal wave with excitation voltage of 20 Vpp. The separation of Cl?, NO3?, NO2?, SO42?, ClO4? and ClO3? was performed within ca. 150 s with baseline resolution and efficiencies between 4.4 × 104 and 1.7 × 105 plates/m. The found limits of detection ranged between 2.5 and 9.5 μmol/L. Last, real samples of post‐blast explosive residues were analyzed on the ME‐C4D devices obtaining successfully the determination of Cl?, NO3? and SO42?. The achieved concentration values varied between 12.8–72.5 mg/L for Cl?, 1.7–293.1 mg/L for NO3? and 1.3–201.3 mg/L for SO42?. The data obtained using ME‐C4D devices were in good agreement with the concentrations found by ion chromatography. The approach reported herein has provided short analysis time, instrumental simplicity, good analytical performance and low cost. Furthermore, the ME‐C4D devices emerge as a powerful and portable analytical platform for on‐site analysis demonstrating to be a promising tool for the crime scene investigation. 相似文献
8.
Xiaogang Gu Yandi Wang Zhouwei Miao Shuguang Lu Zhaofu Qiu Qian Sui Xuhong Guo 《Research on Chemical Intermediates》2017,43(1):1-13
In this study, an environmentally friendly complexing agent, S,S′-ethylenediamine-N,N′-disuccinic acid (EDDS), was applied in Fe(III)-mediated activation of persulfate (PS), and the degradation performance of trichloroethylene (TCE) was investigated. The effects of PS concentration, Fe(III)/EDDS molar ratio, and inorganic anions on TCE degradation were evaluated, and the generated reactive oxygen species responsible for TCE removal were identified. The results showed that nearly complete TCE degradation was achieved with PS of 15.0 mM and a molar ratio of Fe(III)/EDDS of 4:1. An increase in PS concentration or Fe(III)/EDDS molar ratio to a certain value resulted in enhanced TCE degradation. All of the anions (Cl?, HCO3 ?, SO4 2?, and NO 3 ? ) at tested concentrations had negative effects on TCE removal. In addition, investigations using radical probe compounds and radical scavengers revealed that sulfate radicals (SO 4 ·? ), hydroxyl radicals (·OH), and superoxide radical anions (O 2 ·? ) were all generated in the Fe(III)–EDDS/PS system, and ·OH was the primary radical responsible for TCE degradation. In conclusion, the Fe(III)–EDDS-activated PS process is a promising technique for TCE-contaminated groundwater remediation. 相似文献
9.
《Arabian Journal of Chemistry》2023,16(5):104668
In this study, SAA@CS-CB(aluminum-ash carbide slag carbon black doped composite) was prepared by sintering method and modified by impregnation with oxalic acid to obtain SAA@CS-CBoa. Fluoride adsorption experiments were carried out using this composite as adsorbent. With increasing pH values, the adsorption amount of fluoride decreases in the range of 2–11. The pseudo second order equation and Langmuir model were fit to the experimental data, and the adsorption of fluoride by SAA@CS-CBoa exhibited spontaneous and endothermic characteristics. When PO43-, CO32–, SO42-, Cl-, NO3–, Br- and HCO3– anions were individually or combined in solution, the adsorbents exhibited higher fluoride selectivity and sensitivity, while PO43-and CO32– weakened the adsorption of fluoride in solution in the same way regardless of the presence of the other 5 anions. The results of SEM, EDS, XRD and FTIR characterizations showed that the mechanism of fluoride adsorption and removal by SAA@CS-CBoa included the combined effects of electrostatic attraction, surface coordination precipitation and ion exchange. SAA@CS-CBoa is an effective composite material for water adsorption of fluoride, and still has an excellent performance of cyclic regeneration after 10 times adsorption desorption. This study provides a new approach for the utilization of fluoride removal resources for industrial solid waste resource recycling. 相似文献
10.
Simultaneous determination of three chloroacetic acids,three herbicides,and 12 anions in water by ion chromatography 下载免费PDF全文
An ion chromatography method was developed for the simultaneous detection of three soluble herbicides (glyphosate, bentazone and picloram), three chlorine disinfection byproducts (monochloroacetic acid, dichloroacetic acid and trichloroacetic acid) and 12 anions in water (Cl–, Br–, SO42–, CO32–, ClO3–, ClO4–, BrO3–, PO43–, NO2–, NO3–, CH3COO– and COO–). High linearity (r2 > 0.996) was observed for all target analytes for each respective concentration range. The limit of detection and limit of quantitation were between 0.21–0.85 and 0.06–25.46 μg/L, respectively. However, the interference effect of Cl–, NO3–, SO42– and CO32– on some target analytes must be considered during the analysis. Sample pre‐treatment by a hydrogen column (H‐column) required to reduce the negative effect of CO32–. Additionally, sample pre‐treatment by a sliver–hydrogen column (Ag–H‐column) is required when Cl– > 100 mg/L and SO42– < 50 mg/L, and pre‐treatment by both a barium column (Ba‐column) and an H‐column is required when Cl– > 100 mg/L and SO42– > 50 mg/L. When Cl– > 100 mg/L, SO42– > 50 mg/L and CO32– > 20 mg/L, the sample pre‐treatment by either an Ag–H–Ba‐column or an Ag–H‐column and Ba‐column is required to minimize interference. 相似文献
11.
Yan Xiaoju Bao Ruiling Yu Shuili 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(8):1318-1325
The article studies on the effects of six inorganic ions (Ca2+, Mg2+, Cl?, SO 4 2? , H2PO 4 ? , and HCO 3 ? ) on titanium dioxide (TiO2)-based photocatalytic degradation of humic acid (HA). We focus on the effects of the inorganic ions on HA characters, adsorption of HA on TiO2 and photocatalytic degradation of HA. The results indicate that Ca2+ and Mg2+ with HA can form complexes which can decrease the solubility of HA, and then increase the HA adsorbed on TiO2. However, the complex is more difficult to be degraded than HA. The effects of Cl? and SO 4 2? are closely related to their influences on HA solubility. The solubility changes of HA to some extent can enhance the adsorption of HA on TiO2, and promote the photocatalytic degradation. Nevertheless, great solubility decreasing of HA can weaken the photocatalytic degradation. HCO 3 ? and H2PO 4 ? can inhibit the photocatalytic degradation process seriously, because HCO 3 ? and H2PO 4 ? are the strong scavengers of hydroxyl radicals, and can weaken the adsorption of HA on TiO2 due to adsorption competition. 相似文献
12.
A. M. Elokhov A. E. Lesnov O. S. Kudryashova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(10):1972-1977
The effect the salting-out agent anion nature has on the temperature and concentration intervals of the existence of the separation area is established by analyzing the phase diagrams of pseudoternary KCl (KBr, KI, KNO3, K2SO4, K4P2O7)–potassium bis(alkyl polyoxyethylene)phosphate (oxyphos B)–water systems. It is concluded that the anionic salting-out capability is reduced in the order P2O74-> SO42-> Cl? > Br?> NO74-> SO3-> I?. The thermodynamic parameters of phase separation used to interpret the results are calculated. The observed pattern of a change in the salting-out ability of the investigated salts relative to aqueous solutions of the surfactants is in good agreement with the lyotropic (Hofmeister) series. 相似文献
13.
《Analytical letters》2012,45(2):207-219
Abstract A new type of bulk acoustic wave sensing device based on a conductivity-bulk acoustic wave frequency response is applied in ion chromatography to determine nitrate and other inorganic ions in vegetables. The present method has the advantages in its rapidity, simplicity, sensitivity and accuracy. Detection limits (peak=3[sgrave]) are obtained for NO3 ?, Cl?, NO2 ?, H2PO4 ? and SO4 2? at concentrations of 1, 0.6, 1, 7 and 3 ng (on column), respectively. Neither derivatization nor a clean-up step is necessary besides filtration. For the IC analysis, the analytical column is a Shim-pack IC AI column, and the eluent is 2.0 mM phthalic acid solution with pH 4.0. A comparison of IC-SBAW with conventional IC is made. The method allows the simultaneous determination of nitrate and other inorganic ion levels in vegetables. 相似文献
14.
《Electroanalysis》2006,18(23):2354-2360
In this study, simple disk electrodes were tested to monitor nitrate ion level in raw water: a Cu rod (3.1 mm diameter), a Pd rod (4 mm diameter) and an electrochemical copper deposit on Pd disk. These electrodes were able to detect significant variations of nitrate ions rate in synthetic media and in natural water. The influence of some ions such as SO42?, Mg2+, HCO3?, Cl?, NH4+ and Ca2+ were also tested. These electrodes, working at potentials close to ?1.5 V, were able to detect a 2 ppm nitrate ion variation in natural water. The preliminary results showed these electrodes should be promising alert systems for the in‐situ monitoring of nitrate ion level in natural waters. 相似文献
15.
L. G. Bondareva O. P. Kalyakina A. Ya. Bolsunovskii 《Journal of Analytical Chemistry》2006,61(4):354-358
The effect of humic acid on absorption-release processes in the bottom sediments-Yenisei river water system was studied by dual-column ion chromatography and γ-ray spectrometry. With the use of ion chromatography, it was found that processes related to the absorption of SO 4 2? and Cl? anions by a solid phase with the release of NO 3 ? , PO 4 3? , and F? to a liquid phase competed in the test systems as the concentration of water-soluble organic carbon (WSOC) was increased. Only the test anions were released in the systems without the introduction of an additional amount of WSOC as humic acid. With the use of γ-ray spectrometry, it was found that the release of 60Co, 152Eu, and 241Am radionuclides to the liquid phase in the systems with added humic acid began much earlier than in the system without the addition of humic acid. In this case, the amount of released radionuclides was greater than the amount of radioisotopes released in the system without the addition of humic acid: ~25% 241Am, ~3% 152Eu, and ~0.8% 60Co in the system with added humic acid or 0.8% 152Eu and <0.1% 60Co in the system without the addition of humic acid. The 241Am radionuclide was not determined in the system without the addition of humic acid. An increase in the concentration of WSOC in the experimental system of bottom sediments-Yenisei river water initiated the release of 60Co, 152Eu, and 241Am anthropogenic radionuclides from bottom sediments because of the formation of soluble complexes capable of migration. An increase in the concentration of WSOC had almost no effect on the release of 40K and 137Cs radionuclides. 相似文献
16.
A Multifunctional Bimetallic Molecular Device for Ultrasensitive Detection,Naked‐Eye Recognition,and Elimination of Cyanide Ions 下载免费PDF全文
Dr. Cheuk‐Fai Chow Dr. Wing‐Leung Wong Dr. Cheng‐Bin Gong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(37):12984-12990
A new bimetallic FeII–CuII complex was synthesized, characterized, and applied as a selective and sensitive sensor for cyanide detection in water. This complex is the first multifunctional device that can simultaneously detect cyanide ions in real water samples, amplify the colorimetric signal upon detection for naked‐eye recognition at the parts‐per‐million (ppb) level, and convert the toxic cyanide ion into the much safer cyanate ion in situ. The mechanism of the bimetallic complex for high‐selectivity recognition and signaling toward cyanide ions was investigated through a series of binding kinetics of the complex with different analytes, including CN?, SO42?, HCO3?, HPO42?, N3?, CH3COO?, NCS?, NO3?, and Cl? ions. In addition, the use of the indicator/catalyst displacement assay (ICDA) is demonstrated in the present system in which one metal center acts as a receptor and inhibitor and is bridged to another metal center that is responsible for signal transduction and catalysis, thus showing a versatile approach to the design of new multifunctional devices. 相似文献
17.
Nuran Kahriman Serhat Gün Abidin Gümrüküolu Nurettin Yayl Ümmühan Ocak Mira Ocak 《Journal of heterocyclic chemistry》2019,56(9):2612-2618
Anion sensor properties of N‐alkyl‐substituted 1,4′‐diazaflavonium bromides in methanol–water were evaluated by UV–vis spectrometry. Pronounced changes were observed in the absorption spectra of all compounds for only OH?, CO32?, and CN? among F?, Cl?, Br?, I?, OH?, CO32?, NO3?, PO43?, CN?, SO42?, HSO4?, HCO3?, SCN?, NO2?, and P2O72? ions. Two new absorption bands at 385 and 685 nm accompanying the distinct color change for OH?, CO32?, and CN? ions were observed in case of all compounds. The color changes were from pink to blue for CO32? and OH? ions and from pink to purple for CN? ion. Thanks to the distinct color change, the compounds can be used as selective colorimetric anion sensors. Linear changes of absorbance of N‐heptyl‐substituted compound at 385 nm as a function of the ion concentration were used to determine CN? ion in water samples. Detection and quantification limits of the proposed method were 0.94 and 2.82 mg/L, respectively. 相似文献
18.
Pit morphology of Inconel alloy 600 in sulphate (SO4
2-), nitrate (NO3
-) and bicarbonate (HCO3
-) ion-containing 0.5 M sodium chloride (NaCl) solution was analysed in terms of fractal geometry as functions of solution temperature and anion concentration using the potentiostatic current transient technique, scanning electron microscopy, image analysis and ac-impedance spectroscopy. Potentiostatic current transients revealed that the pitting corrosion is facilitated by the increase in solution temperature, irrespective of anion additives, and that it is hindered by the increase in NO3
- and HCO3
- ion concentration, regardless of solution temperature. Above 60 °C, it was also found that the addition of SO4
2- ions impedes pit initiation, but enhances pit growth. The value of fractal dimension D
f of the pits increased with increasing solution temperature and with decreasing NO3
- and HCO3
- ion concentration. Moreover, the value of D
f increased above 60 °C with increasing SO4
2- ion concentration. This is caused by the increase in the ratio of pit perimeter to pit area, implying the formation of pits with micro-branched shape due to the acceleration of the local attack in the pits. From the decrease of the depression parameter with increasing solution temperature, it is inferred that the roughness of the pits increased with increasing solution temperature. In addition, the depression parameter was found to increase with increasing NO3
- and HCO3
- ion concentration. But, above 60 °C, in the case of SO4
2- ion addition, the depression parameter decreased with increasing SO4
2- ion concentration. From the experimental findings, the three-dimensional pit morphology is discussed in terms of the values of D
f of the pits and the depression parameter, with respect to anion concentration and solution temperature. 相似文献
19.
《液相色谱法及相关技术杂志》2012,35(8):1559-1566
Abstract The use of an electrochemical detector for the ion chromatographic detection of non-oxidizable anions such as F?, PO4 ?3, NO3 ?, and SO4 ?2 is described. The electrochemical detector is placed in line after a fiber suppressor and responds to eluent pH changes as the dissociated acids pass through the detector. The intensity of the signal is dependent on the applied potential at the cell with 0.3V being an optimum. Minimum detection limits with a 0.10 mL sample injection volume are below 0.5 ppm for F?, Cl?, PO4 ?3, NO3 ?, and SO4 ?2. No adverse effects on the silver working electrode have been observed. 相似文献
20.
Wenzhi Hu Paul R. Haddad Kyioshi Hasebe Helmy A. Cook James S. Fritz 《Analytical and bioanalytical chemistry》2000,367(7):641-644
The inability to separate fluoride, phosphate and sulfate by electrostatic ion chromatography (EIC) was overcome by using an ODS silica column coated with mixed zwitterionic-cationic surfactants as the stationary phase. The best results were obtained using the zwitterionic surfactant, 3-(N,N-dimethylmyristylammonium)-propanesulfonate (C19H41NO3S), and the cationic surfactant, myristyltrimethylammonium, CH3(CH2)13N+(CH3)3, in a 10:1 molar ratio in the column coating solution. With a dilute solution of sodium tetraborate as the eluent the model analyte anions were completely separated in the following elution order: F–, HPO4 2–, SO4 2–, Cl–, NO2 –, Br–, NO3 –. The very early elution of phosphate and sulfate is most unusual and is unique to this system. Detection limits better than 1.1 × 10–4 mM and linear calibration plots up to 7.0 mM were obtained with a suppressed conductivity system. 相似文献