The soil chemistry of gallium, indium, and thallium is not well defined, particularly with emerging evidence that these elements have toxic properties and may influence food safety. The purpose of this investigation w...The soil chemistry of gallium, indium, and thallium is not well defined, particularly with emerging evidence that these elements have toxic properties and may influence food safety. The purpose of this investigation was to estimate the soil concentrations of gallium, indium, and thallium and determine if these elements have a soil chemistry like aluminum and therefore demonstrate significant concentration correlations with aluminum. Twenty-seven soil series were selected, and the elemental concentrations were determined using aqua regia digestion with analytical determination performed using inductively coupled plasma emission-mass spectroscopy. The concentrations of gallium, indium, and thallium generally compared with the known literature. Aluminum-gallium and aluminum-thallium exhibited significant concentration correlations across the soil horizons of the sampled soils. Aluminum, gallium, and thallium did demonstrate concentration increases in soil horizons having illuviation of phyllosilicates, implying these phyllosilicates have adsorption and isomorphic substitution behaviors involving these elements.展开更多
A method is proposed for the extraction and separation of trivalent gallium,indium and thallium from their corresponding aqueous solutions at 65 deg C with 2,6-bis-(1'-phenyl-3'-methyl-5'-oxopyrazole-4'...A method is proposed for the extraction and separation of trivalent gallium,indium and thallium from their corresponding aqueous solutions at 65 deg C with 2,6-bis-(1'-phenyl-3'-methyl-5'-oxopyrazole-4') pyridineacyl (H_2PMBPP or H_2A) using molten paraffinwax as a diluent. The values of pH_(1/2) for extraction of gallium, indium and thallium are2.62,4.32 and 4.93, respectively. Gallium can he extracted by H_2PMBPP at a lower acid medium. Theeffect of solvent and the composition of the extracted species are reported. And the thermodynamicdata of the extraction are also obtained.展开更多
In this study nine cases of thallium poisoning in a series of homicidal poisoning were analyzed in order to provide more information concerning thallium poisoning. It was found that the most common clinical feature of...In this study nine cases of thallium poisoning in a series of homicidal poisoning were analyzed in order to provide more information concerning thallium poisoning. It was found that the most common clinical feature of thallium poisoning was peripheral neuropathy and paraesthesia was more common than amyasthenia. Understanding of these clinical characteristics of thallium poisoning was helpful to early identification and differential diagnosis. Since the early administration of Prussian Blue, as a specific antidote for thallium poisoning, can substantially improve the prognosis, it is of great importance to establish a correct and early diagnosis.展开更多
BACKGROUND Thallium poisoning is rare and difficult to recognize.Early diagnosis and treatment of thallium-poisoned patients are essential to prevent morbidity and mortality.AIM To evaluate the efficacy of treatments ...BACKGROUND Thallium poisoning is rare and difficult to recognize.Early diagnosis and treatment of thallium-poisoned patients are essential to prevent morbidity and mortality.AIM To evaluate the efficacy of treatments and outcomes of five patients with early diagnosis of acute thallium poisoning.METHODS Five patients who consumed a thallium-contaminated meal were hospitalized in succession,and underwent clinical examinations such as blood tests and electromyography tests.Urine and blood tests confirmed the diagnosis of thallotoxicosis,revealing the occurrence of food poisoning.All patients underwent detoxification treatment,including hemoperfusion(HP)and treatment with Prussian blue(PB).A 24-mo follow-up was performed to evaluate the long-term outcomes on the patients after discharge.RESULTS Initially,the patients presented with symptoms of acute thallium poisoning including hyperalgesia of the limbs and abdominalgia,which may differ from common peripheral neuropathy.Accompanying symptoms such as hepatic damage and alopecia were observed in all the patients,which further confirmed the diagnosis of poisoning.Treatment with chelating agents was ineffective,while HP and treatment with PB drastically decreased the thallium concentration in the urine and blood.With early diagnosis and intervention,four patients had a good prognosis and no permanent sequelae.One patient developed blindness and disability during the 24-mo follow-up period.CONCLUSION Identification of incident cluster and characteristic symptoms is extremely important for early diagnosis of acute thallium poisoning.HP plus PB is essential to improve the prognosis of thallium-poisoned patients.展开更多
We have reported a first principles study of structural, mechanical, electronic, and thermoelectric properties of the monoclinic ternary thallium chalcogenes Tl2MQ3(M = Zr, Hf;Q = S, Se, Te). The electronic band struc...We have reported a first principles study of structural, mechanical, electronic, and thermoelectric properties of the monoclinic ternary thallium chalcogenes Tl2MQ3(M = Zr, Hf;Q = S, Se, Te). The electronic band structure calculations confirm that all compounds exhibit semiconductor character. Especially, Tl2ZrTe3 and Tl2HfTe3 can be good candidates for thermoelectric materials, having narrow band gaps of 0.169 eV and 0.21 eV, respectively. All of the compounds are soft and brittle according to the second-order elastic constant calculations. Low Debye temperatures also support the softness. We have obtained the transport properties of the compounds by using rigid band and constant relaxation time approximations in the context of Boltzmann transport theory. The results show that the compounds could be considered for room temperature thermoelectric applications(ZT ~ 0.9).展开更多
A novel complex of monomeric thallium(III) with the nitrogen donor ligand phenanthroline (phen) has been prepared and characterized by multinuclear NMR (1H, 13C, 205Tl). The three complexes exist in equilibria in DMSO...A novel complex of monomeric thallium(III) with the nitrogen donor ligand phenanthroline (phen) has been prepared and characterized by multinuclear NMR (1H, 13C, 205Tl). The three complexes exist in equilibria in DMSO and acetonitrile solution, which was proved by the 205Tl NMR spectra. The 1H and 13C NMR spectra of tris-phen Tl(III) complex have been measured, where the spin-spin coupling between Tl (I = 1/2) and 13C or 1H signals were observed with the 1H and 13C NMR spectroscopy in acetonitrile. The coupling constants are presented and the chemical shifts of complexes are discussed in detail.展开更多
The cyclic voltammetry(CV) and the square wave technique were used for the investigations of thallium(Ⅰ) underpotential deposition(UPD) on the silver electrode. A solution of 10 \{mmol/L\} HClO 4+10 mmol/L NaCl was s...The cyclic voltammetry(CV) and the square wave technique were used for the investigations of thallium(Ⅰ) underpotential deposition(UPD) on the silver electrode. A solution of 10 \{mmol/L\} HClO 4+10 mmol/L NaCl was selected as the supporting electrolyte. The calibration plots for Tl(Ⅰ) concentration in the range of 2×10 -9 -1×10 -7 mol/L were obtained. The detection limit was 5×10 -10 mol/L. For the solutions of 4 0×10 -9 mol/L thallium added before the urine sample pretreatment procedure, the average recovery was 105 6% with a relative standard deviation(RSD) of 15 5%.展开更多
The potential of modified multiwallcd carbon nanotubes, as a solid-phase extraction sorbent for the simultaneous separation and preconcentration of zinc and thallium has been investigated. Zinc and thallium were adsor...The potential of modified multiwallcd carbon nanotubes, as a solid-phase extraction sorbent for the simultaneous separation and preconcentration of zinc and thallium has been investigated. Zinc and thallium were adsorbed quantitatively onto modified multiwalled carbon nanotubes in the pH range of 3 - 6.5. Parameters influencing the simultaneous preconcentration of Zn(II) and Tl(I) ions such as pH of the sample, sample and eluent flow rate, type and volume of elution solution and interfering ions, have been examined and optimized. Linearity was maintained between 0.1 to 20.0 μg?mL–1 for thallium and 20.0 ng?mL–1 to 5.0 μg?mL–1 for zinc in the final solution. The defection limits based on three times the standard deviation of the blank signal (n = 8) for thallium and zinc were 5.1 and 1.4 ng?mL–1, respectively. Seven replicate determination of a mixture of 5.0 and 0.2 μg?mL–1 of thallium and zinc in the final solution gave a mean absorbance of 0.085 and 0.074 with relative standard deviation 1.5% and 1.7%, respectively. The method has been applied for the determination of trace amounts of zinc and thallium in biological and water sample with satisfactory results.展开更多
Thallium is a heavy metal highly toxic to the biosphere. It can be determined by anodic stripping voltammetry after deposition on mercury film. The aim of this work is to study the conditions and mechanisms of deposit...Thallium is a heavy metal highly toxic to the biosphere. It can be determined by anodic stripping voltammetry after deposition on mercury film. The aim of this work is to study the conditions and mechanisms of deposition of Hg on glassy carbon electrode and Tl on Hg film by cyclic voltammetry, scanning electron microscopy, chronoamperometry and impedance techniques. The results showed a germination and growth of a 3D Hg phase on glassy carbon electrode. Similarly, the electrodeposition of Tl on Hg follows a 3D three-dimensional nucleation with diffusion controlled growth. The impedance measurements reveal an easier charge transfer on the Tl film.展开更多
By standard method to determine thallium content in 34 batches of cosmetic products sold in Shenzhen,including cushions and sunscreens for children,all results of samples are within the range of not detected to 0.62 m...By standard method to determine thallium content in 34 batches of cosmetic products sold in Shenzhen,including cushions and sunscreens for children,all results of samples are within the range of not detected to 0.62 mg/kg.By calculating the Maximum Theoretical Safety Limit,according to guidance of Scientific Committee on Consumer Safety(SCCS)of European Union and Toxicological Review of Thallium and Compounds 2009 of United States Environmental Protection Agency(EPA)to assess the risk of cosmetic products.As a result,if the mean concentration of thallium in different kind of cosmetic products does not exceed 0.031 mg/kg,the products will not show significant toxicological risk for consumers.展开更多
This paper deals with thallium in typical low-temperature deopits of Au, Tl, As,Sb and Hg in South China with respect to its mode of occurrence, minerals and geochemicalcorrelations with many other coexisting major an...This paper deals with thallium in typical low-temperature deopits of Au, Tl, As,Sb and Hg in South China with respect to its mode of occurrence, minerals and geochemicalcorrelations with many other coexisting major and trace elements. Criteria are proposed for i-dentifying independent thallium deposits and thallium-bearing deposits and the Nanhua realgardeposit is classified for the first time as an independent thallium deposit. Tl, F, Cl, I and B aresuggested as indicators for low-temperature mineralization with examples furnished for their ap-plications.展开更多
Lanmuchangite is a new thallium hydrous sulfate from the oxidation zone hosting rich thallium ore bodies in the Lanmuchang thallium(mercury) ore deposit, Xinren County, Guizhou Province, China. This new mineral is nam...Lanmuchangite is a new thallium hydrous sulfate from the oxidation zone hosting rich thallium ore bodies in the Lanmuchang thallium(mercury) ore deposit, Xinren County, Guizhou Province, China. This new mineral is named after the locality where it was discovered. The mineral is associated with melanterite, pickeringite, potassium alum, jarosite, gypsum, arsenic blane, sulphur and some unknown minerals. The aggregates of lanmuchangite range from 2 to 10 mm in size. In general, the aggregates are compact and massive in form and are composed of anhedral granular crystals measuring in size from 40 to 90μm, but the single crystal grains show distinct boundaries. Parallel columnar aggregates are occasionally seen, which are composed of subhedral to euhedral columnar crystals ranging in size from 15 to 65μm. White, light yellow to white in color, glassy in luster and transparent. Hv-{mess.}=94-124 kg/mm+2, Hm={3.1}-{3.4}, density={2.22} g/cm+3. Under the polarization microscope the mineral is colorless and homogeneous, with N-{meas.}={1.495}. It is easily water-soluble. The average chemical composition is: Tl-2O={33.25}, Al-2O-3={8.07}, SO-3={25.19}, SiO-2={0.10}, K-2O={0.35}, CaO={0.08}, MgO={0.06}, FeO={0.04} and H-2O={33.46} [the crystal water (H-2O) was measured by thermogravimetery (TG) while the other composition were determined by electron microprobe], totaling {100.60%}. The empirical formula is (Tl-{1.00}K-{0.05})-{1.05} (Al-{1.01}Si-{0.01}Ca-{0.01}Mg-{0.01})-{1.04}-{2.01}·{11.88} H-2O and the simplified formula is TlAl-2·12H-2O. The compatibility of lanmuchangite is {-0.03} and its value falls within the range of {±0.020}-{±0.039}, so the compatibility is excellent. Its TG curve demonstrated that the crystal water was lost (i.e., dewatering) in stages at 101, 130 and 230℃. At the temperature of 243℃ the process of dewatering came to the end and the sum of lost crystal water reaches {33.30} wt%. IR spectroscopic analysis showed that the absorption bands 3374-3147 cm+{-1} and 1655-1648 cm+{-1} are due to tensile and bending vibration of crystal water molecules (H-2O) whereas those at 1131 cm+{-1} and 605 cm+{-1} are attributed to tensile and bending vibration of group +{2-}. Lanmuchangite is of the isometric system, with space group=Pa3, a={12.212(5)}, v=1821(2)+3, and Z=4. The strongest diffraction lines from the X-ray power diffraction data are {4.314}(100, 220), {2.801}(70, 331), {7.03}(54, 111), {2.731}(35, 420), {6.11}(27, 200), {3.524}(24, 222), {3.676}(22, 311), {3.051}(22, 400), {2.350}(21, 511), {3.263}(20, 321), {2.494}(20, 422), {1.932}(19, 620).展开更多
The water system in a rural area of Lanmuchang in Southwest Guizhou is facing a risk of thallium (Tl) contamination due to Tl mineralization around the area. The major trace elements and Tl in the water system are stu...The water system in a rural area of Lanmuchang in Southwest Guizhou is facing a risk of thallium (Tl) contamination due to Tl mineralization around the area. The major trace elements and Tl in the water system are studied to understand the hydrogeochemical processes of Tl constrained by Tl mineralization. The results showed that the dispersion pattern of Tl follows a descending order in concentration from mine groundwater (deep groundwater) →stream water→shallow groundwater→background water, reflecting the impact of Tl mineralization on the hydrogeochemical composition. Tl concentrations in stream water in both regimes are remarkably higher (2-30 fold) downstream than up- and mid-streams, probably caused by the unidentified discharge of deep groundwater. Low Tl levels are detected in the current drinking water, however, the highly elevated Tl in stream water and ground water may pose a potential environmental risk through daily washing and agricultural irrigation. This study suggests that human activities, such as agricultural irrigation, could intensify the environmental risk of Tl.展开更多
The extraction of thallium (Ⅲ) with di (2-ethylhexyl) sulfoxide from hydrochloric acid media was studied by means of single-drop method.An extraction rate expression and the activation energysupport a mechanism,in wh...The extraction of thallium (Ⅲ) with di (2-ethylhexyl) sulfoxide from hydrochloric acid media was studied by means of single-drop method.An extraction rate expression and the activation energysupport a mechanism,in which the ratelimiting step is HTlCl4+DEHSO(i) =HTlCl4DEHSO(i).展开更多
Thallium is a highly toxic metal,and trace amount of thallium(I)(Tl+)in potable water could cause a severe water crisis,which arouses the exploitation of highly-effective technology for purification of Tl+contaminated...Thallium is a highly toxic metal,and trace amount of thallium(I)(Tl+)in potable water could cause a severe water crisis,which arouses the exploitation of highly-effective technology for purification of Tl+contaminated water.This report proposes the multi-layered Prussian blue(PB)-decorated composite membranes(PBx@PDA/PEI-FP)based on the aminated filter papers for Tl+uptake.Extensively characterization by Fourier transform infrared spectrometer-attenuated total reflectance,scanning electron microscope,thermogravimetric analysis,X-ray photoelectron spectroscopy and X-ray diffraction were performed to confirm the in situ growth of cubic PB crystals on filter paper membrane surfaces via the aminated layers,and the successful fabrication of multi-layered PB overcoats via the increasing of aminated layers.The effect of PB layers on Tl+removal by PBx@PDA/PEI-FP from simulated drinking water was evaluated as well as the influence of different experimental conditions.A trade-off between PB decoration layer number and PB distribution sizes is existed in Tl+uptake by PBx@PDA/PEI-FP.The double-layered PB2@PDA/PEI-FP membrane showed the maximum sorption capacity,but its Tl+uptake performance was weakened by the acid,coexisting ions(K+and Na+)and powerful operation pressure,during filtrating a large volume of low-concentrated Tl+-containing water.However,the negative effect of coexisting ions on the Tl+uptake could be effectively eliminated in weak alkaline water,and the Tl+removal was increased up to 100%without any pressure driving for PB2@PDA/PEI-FP membrane.Most importantly,PB2@PDA/PEI-FP displayed the high-efficiency and high-selectivity in purifying the Tl+-spiked Pearl River water,in which the residual Tl+in filtrate was less than 2μg·L^(–1) to meet the drinking water standard of United States Environmental Protection Agency.This work provides a feasible avenue to safeguard the drinking water in remote and underdeveloped area via the energy-free operation.展开更多
Thallium contamination in water can cause great danger to the environment.In this study,we synthesized manganese oxide-coated sand(MOCS)and investigated the transport and retention behaviors of Tl(I)in MOCS under diff...Thallium contamination in water can cause great danger to the environment.In this study,we synthesized manganese oxide-coated sand(MOCS)and investigated the transport and retention behaviors of Tl(I)in MOCS under different conditions.Characterization methods combined with a two-site nonequilibrium transport model were applied to explore the retentionmechanisms.The results showed that Tl(I)mobility was strongly inhibited in MOCS media,and the retention capacity calculated from the fitted model was 510.41 mg/g under neutral conditions.The retention process included adsorption and oxidative precipitation by the manganese oxides coated on the sand surface.Cotransport with the same concentration of Mn(II)led to halving Tl(I)retention due to competition for reactive sites.Enhanced Tl(I)retention was observed under alkaline conditions,as increasing pH promoted electronegativity on the media surface.Moreover,the competitive cation Ca^(2+)significantly weakened Tl(I)retention by occupying adsorption sites.These findings provide new insights into understanding Tl(I)transport behavior in water-saturated porous media and suggest that manganese oxide-coated sand can be a cost-effective filter media for treating Tl-contaminated water.展开更多
Iron plaque is a Fe-containing oxide film produced by the oxidation of Fe(II)in the rice root system under the combined action of oxygen infiltration and other microorganisms.Owing to its special surface structure and...Iron plaque is a Fe-containing oxide film produced by the oxidation of Fe(II)in the rice root system under the combined action of oxygen infiltration and other microorganisms.Owing to its special surface structure and physio-chemical properties,the iron plaque has a strong absorption capacity for a variety of heavy metal ions.This study aimed to first investigate the effects of Fe species on the geochemical fractionation of Tl in typical paddy soil systems affected by industrial activities,followed by pot culture experiments to probe the effects of Fe species on the uptake and translocation of Tl in rice plants.The results of field work preliminarily showed that iron at different valences affected the conversion of the Tl geochemical fraction in the soil.Oxidizable Tl exerted significant positive correlation relationships with Fe2+and negative correlation relationships with Fe3+,while reducible Tl only displayed a positive correlation with Fe3+.Further analysis by pot culture experiments revealed that the contents of Fe were significantly positively correlated with Tl contents in Fe plaque(R2=0.529).In contrast,the water-soluble Tl contents in the soil were significantly negatively correlated with the contents of Fe(R2=–0.90,p<0.05).It suggests that the iron plaque promoted the absorption and fixation of Tl on the root surface of rice plants,causing Tl to accumulate in the iron plaque.Besides,the Tl content in the Fe plaque on the root surface of rice plants was greater than that in the above-ground tissues,which indicates that most Fe plaque exerts a certain degree of inhibition on Tl migration into the above-ground tissues of rice plants.All these findings indicate that Fe film is also an important carrier of Tl transfer in the soil–rice plant system,which provides new scientific support for the remediation of typical Tl-contaminated rice fields.展开更多
文摘The soil chemistry of gallium, indium, and thallium is not well defined, particularly with emerging evidence that these elements have toxic properties and may influence food safety. The purpose of this investigation was to estimate the soil concentrations of gallium, indium, and thallium and determine if these elements have a soil chemistry like aluminum and therefore demonstrate significant concentration correlations with aluminum. Twenty-seven soil series were selected, and the elemental concentrations were determined using aqua regia digestion with analytical determination performed using inductively coupled plasma emission-mass spectroscopy. The concentrations of gallium, indium, and thallium generally compared with the known literature. Aluminum-gallium and aluminum-thallium exhibited significant concentration correlations across the soil horizons of the sampled soils. Aluminum, gallium, and thallium did demonstrate concentration increases in soil horizons having illuviation of phyllosilicates, implying these phyllosilicates have adsorption and isomorphic substitution behaviors involving these elements.
基金This project is financially supported in part by the Gansu Province Natural Science Foundation (ZR96016) the KJCXGC-01 of NWNU, 2000, China
文摘A method is proposed for the extraction and separation of trivalent gallium,indium and thallium from their corresponding aqueous solutions at 65 deg C with 2,6-bis-(1'-phenyl-3'-methyl-5'-oxopyrazole-4') pyridineacyl (H_2PMBPP or H_2A) using molten paraffinwax as a diluent. The values of pH_(1/2) for extraction of gallium, indium and thallium are2.62,4.32 and 4.93, respectively. Gallium can he extracted by H_2PMBPP at a lower acid medium. Theeffect of solvent and the composition of the extracted species are reported. And the thermodynamicdata of the extraction are also obtained.
文摘In this study nine cases of thallium poisoning in a series of homicidal poisoning were analyzed in order to provide more information concerning thallium poisoning. It was found that the most common clinical feature of thallium poisoning was peripheral neuropathy and paraesthesia was more common than amyasthenia. Understanding of these clinical characteristics of thallium poisoning was helpful to early identification and differential diagnosis. Since the early administration of Prussian Blue, as a specific antidote for thallium poisoning, can substantially improve the prognosis, it is of great importance to establish a correct and early diagnosis.
基金National Natural Science Foundation of China,No.81701058Shandong Academy of Sciences,No.ZR2017PH027and China Postdoctoral Science Foundation,No.2017M612288.
文摘BACKGROUND Thallium poisoning is rare and difficult to recognize.Early diagnosis and treatment of thallium-poisoned patients are essential to prevent morbidity and mortality.AIM To evaluate the efficacy of treatments and outcomes of five patients with early diagnosis of acute thallium poisoning.METHODS Five patients who consumed a thallium-contaminated meal were hospitalized in succession,and underwent clinical examinations such as blood tests and electromyography tests.Urine and blood tests confirmed the diagnosis of thallotoxicosis,revealing the occurrence of food poisoning.All patients underwent detoxification treatment,including hemoperfusion(HP)and treatment with Prussian blue(PB).A 24-mo follow-up was performed to evaluate the long-term outcomes on the patients after discharge.RESULTS Initially,the patients presented with symptoms of acute thallium poisoning including hyperalgesia of the limbs and abdominalgia,which may differ from common peripheral neuropathy.Accompanying symptoms such as hepatic damage and alopecia were observed in all the patients,which further confirmed the diagnosis of poisoning.Treatment with chelating agents was ineffective,while HP and treatment with PB drastically decreased the thallium concentration in the urine and blood.With early diagnosis and intervention,four patients had a good prognosis and no permanent sequelae.One patient developed blindness and disability during the 24-mo follow-up period.CONCLUSION Identification of incident cluster and characteristic symptoms is extremely important for early diagnosis of acute thallium poisoning.HP plus PB is essential to improve the prognosis of thallium-poisoned patients.
文摘We have reported a first principles study of structural, mechanical, electronic, and thermoelectric properties of the monoclinic ternary thallium chalcogenes Tl2MQ3(M = Zr, Hf;Q = S, Se, Te). The electronic band structure calculations confirm that all compounds exhibit semiconductor character. Especially, Tl2ZrTe3 and Tl2HfTe3 can be good candidates for thermoelectric materials, having narrow band gaps of 0.169 eV and 0.21 eV, respectively. All of the compounds are soft and brittle according to the second-order elastic constant calculations. Low Debye temperatures also support the softness. We have obtained the transport properties of the compounds by using rigid band and constant relaxation time approximations in the context of Boltzmann transport theory. The results show that the compounds could be considered for room temperature thermoelectric applications(ZT ~ 0.9).
基金The authors are grateful to the Swedish Natural Science Research Council (NFR) for financial support and together with the Knut and Alice Wallenberg foundation, for providing funds for purchasing the NMR spectrometersFinancial support of Overseas
文摘A novel complex of monomeric thallium(III) with the nitrogen donor ligand phenanthroline (phen) has been prepared and characterized by multinuclear NMR (1H, 13C, 205Tl). The three complexes exist in equilibria in DMSO and acetonitrile solution, which was proved by the 205Tl NMR spectra. The 1H and 13C NMR spectra of tris-phen Tl(III) complex have been measured, where the spin-spin coupling between Tl (I = 1/2) and 13C or 1H signals were observed with the 1H and 13C NMR spectroscopy in acetonitrile. The coupling constants are presented and the chemical shifts of complexes are discussed in detail.
文摘The cyclic voltammetry(CV) and the square wave technique were used for the investigations of thallium(Ⅰ) underpotential deposition(UPD) on the silver electrode. A solution of 10 \{mmol/L\} HClO 4+10 mmol/L NaCl was selected as the supporting electrolyte. The calibration plots for Tl(Ⅰ) concentration in the range of 2×10 -9 -1×10 -7 mol/L were obtained. The detection limit was 5×10 -10 mol/L. For the solutions of 4 0×10 -9 mol/L thallium added before the urine sample pretreatment procedure, the average recovery was 105 6% with a relative standard deviation(RSD) of 15 5%.
文摘The potential of modified multiwallcd carbon nanotubes, as a solid-phase extraction sorbent for the simultaneous separation and preconcentration of zinc and thallium has been investigated. Zinc and thallium were adsorbed quantitatively onto modified multiwalled carbon nanotubes in the pH range of 3 - 6.5. Parameters influencing the simultaneous preconcentration of Zn(II) and Tl(I) ions such as pH of the sample, sample and eluent flow rate, type and volume of elution solution and interfering ions, have been examined and optimized. Linearity was maintained between 0.1 to 20.0 μg?mL–1 for thallium and 20.0 ng?mL–1 to 5.0 μg?mL–1 for zinc in the final solution. The defection limits based on three times the standard deviation of the blank signal (n = 8) for thallium and zinc were 5.1 and 1.4 ng?mL–1, respectively. Seven replicate determination of a mixture of 5.0 and 0.2 μg?mL–1 of thallium and zinc in the final solution gave a mean absorbance of 0.085 and 0.074 with relative standard deviation 1.5% and 1.7%, respectively. The method has been applied for the determination of trace amounts of zinc and thallium in biological and water sample with satisfactory results.
文摘Thallium is a heavy metal highly toxic to the biosphere. It can be determined by anodic stripping voltammetry after deposition on mercury film. The aim of this work is to study the conditions and mechanisms of deposition of Hg on glassy carbon electrode and Tl on Hg film by cyclic voltammetry, scanning electron microscopy, chronoamperometry and impedance techniques. The results showed a germination and growth of a 3D Hg phase on glassy carbon electrode. Similarly, the electrodeposition of Tl on Hg follows a 3D three-dimensional nucleation with diffusion controlled growth. The impedance measurements reveal an easier charge transfer on the Tl film.
文摘By standard method to determine thallium content in 34 batches of cosmetic products sold in Shenzhen,including cushions and sunscreens for children,all results of samples are within the range of not detected to 0.62 mg/kg.By calculating the Maximum Theoretical Safety Limit,according to guidance of Scientific Committee on Consumer Safety(SCCS)of European Union and Toxicological Review of Thallium and Compounds 2009 of United States Environmental Protection Agency(EPA)to assess the risk of cosmetic products.As a result,if the mean concentration of thallium in different kind of cosmetic products does not exceed 0.031 mg/kg,the products will not show significant toxicological risk for consumers.
文摘This paper deals with thallium in typical low-temperature deopits of Au, Tl, As,Sb and Hg in South China with respect to its mode of occurrence, minerals and geochemicalcorrelations with many other coexisting major and trace elements. Criteria are proposed for i-dentifying independent thallium deposits and thallium-bearing deposits and the Nanhua realgardeposit is classified for the first time as an independent thallium deposit. Tl, F, Cl, I and B aresuggested as indicators for low-temperature mineralization with examples furnished for their ap-plications.
文摘Lanmuchangite is a new thallium hydrous sulfate from the oxidation zone hosting rich thallium ore bodies in the Lanmuchang thallium(mercury) ore deposit, Xinren County, Guizhou Province, China. This new mineral is named after the locality where it was discovered. The mineral is associated with melanterite, pickeringite, potassium alum, jarosite, gypsum, arsenic blane, sulphur and some unknown minerals. The aggregates of lanmuchangite range from 2 to 10 mm in size. In general, the aggregates are compact and massive in form and are composed of anhedral granular crystals measuring in size from 40 to 90μm, but the single crystal grains show distinct boundaries. Parallel columnar aggregates are occasionally seen, which are composed of subhedral to euhedral columnar crystals ranging in size from 15 to 65μm. White, light yellow to white in color, glassy in luster and transparent. Hv-{mess.}=94-124 kg/mm+2, Hm={3.1}-{3.4}, density={2.22} g/cm+3. Under the polarization microscope the mineral is colorless and homogeneous, with N-{meas.}={1.495}. It is easily water-soluble. The average chemical composition is: Tl-2O={33.25}, Al-2O-3={8.07}, SO-3={25.19}, SiO-2={0.10}, K-2O={0.35}, CaO={0.08}, MgO={0.06}, FeO={0.04} and H-2O={33.46} [the crystal water (H-2O) was measured by thermogravimetery (TG) while the other composition were determined by electron microprobe], totaling {100.60%}. The empirical formula is (Tl-{1.00}K-{0.05})-{1.05} (Al-{1.01}Si-{0.01}Ca-{0.01}Mg-{0.01})-{1.04}-{2.01}·{11.88} H-2O and the simplified formula is TlAl-2·12H-2O. The compatibility of lanmuchangite is {-0.03} and its value falls within the range of {±0.020}-{±0.039}, so the compatibility is excellent. Its TG curve demonstrated that the crystal water was lost (i.e., dewatering) in stages at 101, 130 and 230℃. At the temperature of 243℃ the process of dewatering came to the end and the sum of lost crystal water reaches {33.30} wt%. IR spectroscopic analysis showed that the absorption bands 3374-3147 cm+{-1} and 1655-1648 cm+{-1} are due to tensile and bending vibration of crystal water molecules (H-2O) whereas those at 1131 cm+{-1} and 605 cm+{-1} are attributed to tensile and bending vibration of group +{2-}. Lanmuchangite is of the isometric system, with space group=Pa3, a={12.212(5)}, v=1821(2)+3, and Z=4. The strongest diffraction lines from the X-ray power diffraction data are {4.314}(100, 220), {2.801}(70, 331), {7.03}(54, 111), {2.731}(35, 420), {6.11}(27, 200), {3.524}(24, 222), {3.676}(22, 311), {3.051}(22, 400), {2.350}(21, 511), {3.263}(20, 321), {2.494}(20, 422), {1.932}(19, 620).
文摘The water system in a rural area of Lanmuchang in Southwest Guizhou is facing a risk of thallium (Tl) contamination due to Tl mineralization around the area. The major trace elements and Tl in the water system are studied to understand the hydrogeochemical processes of Tl constrained by Tl mineralization. The results showed that the dispersion pattern of Tl follows a descending order in concentration from mine groundwater (deep groundwater) →stream water→shallow groundwater→background water, reflecting the impact of Tl mineralization on the hydrogeochemical composition. Tl concentrations in stream water in both regimes are remarkably higher (2-30 fold) downstream than up- and mid-streams, probably caused by the unidentified discharge of deep groundwater. Low Tl levels are detected in the current drinking water, however, the highly elevated Tl in stream water and ground water may pose a potential environmental risk through daily washing and agricultural irrigation. This study suggests that human activities, such as agricultural irrigation, could intensify the environmental risk of Tl.
文摘The extraction of thallium (Ⅲ) with di (2-ethylhexyl) sulfoxide from hydrochloric acid media was studied by means of single-drop method.An extraction rate expression and the activation energysupport a mechanism,in which the ratelimiting step is HTlCl4+DEHSO(i) =HTlCl4DEHSO(i).
基金supported by the National Natural Science Foundation of China(Grant Nos.22006026,52270001)Guangdong Basic and Applied Basic Research Foundation(Grant Nos.2023A1515012506,2019A1515110546)+4 种基金Science and Technology Program of Guangzhou(Grant No.202102080160)Project of Young Innovative Talents in Colleges and Universities of Guangdong Province(Grant No.2019KQNCX111)Outstanding Youth Project of Guangdong Natural Science Foundation(Grant No.2022B1515020030)Guangzhou Science and Technology Project(Grant Nos.202201020530,202201020200)Research Project of Guangzhou University(Grant No.YJ2023026).
文摘Thallium is a highly toxic metal,and trace amount of thallium(I)(Tl+)in potable water could cause a severe water crisis,which arouses the exploitation of highly-effective technology for purification of Tl+contaminated water.This report proposes the multi-layered Prussian blue(PB)-decorated composite membranes(PBx@PDA/PEI-FP)based on the aminated filter papers for Tl+uptake.Extensively characterization by Fourier transform infrared spectrometer-attenuated total reflectance,scanning electron microscope,thermogravimetric analysis,X-ray photoelectron spectroscopy and X-ray diffraction were performed to confirm the in situ growth of cubic PB crystals on filter paper membrane surfaces via the aminated layers,and the successful fabrication of multi-layered PB overcoats via the increasing of aminated layers.The effect of PB layers on Tl+removal by PBx@PDA/PEI-FP from simulated drinking water was evaluated as well as the influence of different experimental conditions.A trade-off between PB decoration layer number and PB distribution sizes is existed in Tl+uptake by PBx@PDA/PEI-FP.The double-layered PB2@PDA/PEI-FP membrane showed the maximum sorption capacity,but its Tl+uptake performance was weakened by the acid,coexisting ions(K+and Na+)and powerful operation pressure,during filtrating a large volume of low-concentrated Tl+-containing water.However,the negative effect of coexisting ions on the Tl+uptake could be effectively eliminated in weak alkaline water,and the Tl+removal was increased up to 100%without any pressure driving for PB2@PDA/PEI-FP membrane.Most importantly,PB2@PDA/PEI-FP displayed the high-efficiency and high-selectivity in purifying the Tl+-spiked Pearl River water,in which the residual Tl+in filtrate was less than 2μg·L^(–1) to meet the drinking water standard of United States Environmental Protection Agency.This work provides a feasible avenue to safeguard the drinking water in remote and underdeveloped area via the energy-free operation.
基金This work was supported by the National Natural Science Foundation of China(Nos.51878092 and 52070029)。
文摘Thallium contamination in water can cause great danger to the environment.In this study,we synthesized manganese oxide-coated sand(MOCS)and investigated the transport and retention behaviors of Tl(I)in MOCS under different conditions.Characterization methods combined with a two-site nonequilibrium transport model were applied to explore the retentionmechanisms.The results showed that Tl(I)mobility was strongly inhibited in MOCS media,and the retention capacity calculated from the fitted model was 510.41 mg/g under neutral conditions.The retention process included adsorption and oxidative precipitation by the manganese oxides coated on the sand surface.Cotransport with the same concentration of Mn(II)led to halving Tl(I)retention due to competition for reactive sites.Enhanced Tl(I)retention was observed under alkaline conditions,as increasing pH promoted electronegativity on the media surface.Moreover,the competitive cation Ca^(2+)significantly weakened Tl(I)retention by occupying adsorption sites.These findings provide new insights into understanding Tl(I)transport behavior in water-saturated porous media and suggest that manganese oxide-coated sand can be a cost-effective filter media for treating Tl-contaminated water.
基金supported by the National Natural Science Foundation of China(Nos.42173007,41830753,41873015)Natural Science Foundation of Guangdong Province,China(Nos.2021B1515020078,2021A1515011588,2014A030313527,the one granted to Jin Wang starting from 2023)+1 种基金Earth Critical Zone and Eco-geochemistry(No.PT252022024)the“Challenge Cup”program(Xiaoyin Zhang,Han Cai,Yuhua Zhang,Haoran Li,Mengqing Sun,Wenhuan Yuan and Ying Zhang).
文摘Iron plaque is a Fe-containing oxide film produced by the oxidation of Fe(II)in the rice root system under the combined action of oxygen infiltration and other microorganisms.Owing to its special surface structure and physio-chemical properties,the iron plaque has a strong absorption capacity for a variety of heavy metal ions.This study aimed to first investigate the effects of Fe species on the geochemical fractionation of Tl in typical paddy soil systems affected by industrial activities,followed by pot culture experiments to probe the effects of Fe species on the uptake and translocation of Tl in rice plants.The results of field work preliminarily showed that iron at different valences affected the conversion of the Tl geochemical fraction in the soil.Oxidizable Tl exerted significant positive correlation relationships with Fe2+and negative correlation relationships with Fe3+,while reducible Tl only displayed a positive correlation with Fe3+.Further analysis by pot culture experiments revealed that the contents of Fe were significantly positively correlated with Tl contents in Fe plaque(R2=0.529).In contrast,the water-soluble Tl contents in the soil were significantly negatively correlated with the contents of Fe(R2=–0.90,p<0.05).It suggests that the iron plaque promoted the absorption and fixation of Tl on the root surface of rice plants,causing Tl to accumulate in the iron plaque.Besides,the Tl content in the Fe plaque on the root surface of rice plants was greater than that in the above-ground tissues,which indicates that most Fe plaque exerts a certain degree of inhibition on Tl migration into the above-ground tissues of rice plants.All these findings indicate that Fe film is also an important carrier of Tl transfer in the soil–rice plant system,which provides new scientific support for the remediation of typical Tl-contaminated rice fields.