In order to build method for measuring of elements in honey, the contents of Ba, Cu, Pb, Cd, As, Hg, Cr, Mn, Se had been determined by microwave diges- tion (MWD) and actively coupled plasma atomic emission spectrom...In order to build method for measuring of elements in honey, the contents of Ba, Cu, Pb, Cd, As, Hg, Cr, Mn, Se had been determined by microwave diges- tion (MWD) and actively coupled plasma atomic emission spectrometry (ICP-AES). The results show that, the range of heavy metal elements were in the range of 0- 10.0 mg/L, with good linear relationship. In addition, all correlation coefficients kept higher than 0.999, and the recovery rate of ample added with standard solution was in 94.1%-110%. By comparison with the result of chemical experiment, the method was quickly accessible and convenient, widely used in the measurement of elements in honey, with satisfactory results.展开更多
In order to develop a method for measuring of elements in Sipunculus nudus, the contents of Cu, Pb, Cd, Cr, Mn, As, Hg and Ba were determined by actively coupled plasma atomic emission spectrometry (MWD) and microwa...In order to develop a method for measuring of elements in Sipunculus nudus, the contents of Cu, Pb, Cd, Cr, Mn, As, Hg and Ba were determined by actively coupled plasma atomic emission spectrometry (MWD) and microwave digestion (ICP-AES). The results showed that correlation coefficients al kept higher than 0.999 and the recovery rates of sample added standard solutions were in 98%-114%. The results indicated that the contents of Cu, Pb, Cd, Cr, Mn, As, Hg and Ba were 17.119, 3.781, 0.695, 7.351, 1997.982, 0.620, 0.144, 4.249 mg/kg respectively. The contents of Mn exceeded national limit by hundredfold, Cd sevenfold, Pd fourfold, Cd three-and-a-half-fold, and As onefold. Sipunculs nudus became seriously pol uted. Therefore, it is necessary to formulate robust policies to fol ow closely and pay close attention to coastal areas pol ution around Dongfang City.展开更多
Cadmium (Cd) concentrations in the water extracts of ten contaminated soils by arsenic (As) with various iron (Fe) contents were measured using inductively coupled plasma atomic emission spectrometry (ICP-AES)...Cadmium (Cd) concentrations in the water extracts of ten contaminated soils by arsenic (As) with various iron (Fe) contents were measured using inductively coupled plasma atomic emission spectrometry (ICP-AES) and electrothermal atomic absorption spectrometry (ETAAS), Due to the potential spectral interferences of As and Fe in the quantification of Cd, two methods were used for the background compensation. The first method was based on the use of a deuterium lamp (BGCD2 mode). The second one required a Cd hollow cathode lamp pulsated with a current for which the intensity varies in the course of time (BGCSR mode). The results showed that the choices of the analytical technique and the method used for the background compensation depend on the Cd, As and Fe concentrations in the solution and the concentration ratios As/Cd or/and Fe/Cd. In comparison with the ICP-AES and the ETAAS in combination with the BGCD2 mode, it was shown that the high-speed self-reversal method (HSSR) was a more appropriate method to correct As and Fe spectral interferences during the Cd measurements. On the other hand, depending on the Cd concentration, it was established that no significant Fe interference occurred during the Cd determination even if Fe concentration was 50 mg/L, reflecting the efficiency of the HSSR method to overcome the Fe interferences in the determination of Cd concentration by ETAAS without any matrix modifier in water extracts.展开更多
Meretricis concha is a kind of marine traditional Chinese medicine(TCM), and has been commonly used for the treatment of asthma and scald burns. In order to investigate the relationship between the inorganic elemental...Meretricis concha is a kind of marine traditional Chinese medicine(TCM), and has been commonly used for the treatment of asthma and scald burns. In order to investigate the relationship between the inorganic elemental fingerprint and the geographical origin identification of Meretricis concha, the elemental contents of M. concha from five sampling points in Rushan Bay have been determined by means of inductively coupled plasma optical emission spectrometry(ICP-OES). Based on the contents of 14 inorganic elements(Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se, and Zn), the inorganic elemental fingerprint which well reflects the elemental characteristics was constructed. All the data from the five sampling points were discriminated with accuracy through hierarchical cluster analysis(HCA) and principle component analysis(PCA), indicating that a four-factor model which could explain approximately 80% of the detection data was established, and the elements Al, As, Cd, Cu, Ni and Pb could be viewed as the characteristic elements. This investigation suggests that the inorganic elemental fingerprint combined with multivariate statistical analysis is a promising method for verifying the geographical origin of M. concha, and this strategy should be valuable for the authenticity discrimination of some marine TCM.展开更多
The goal of this paper is to explore the relationship between the inorganic elemental fingerprint and the geographical origin identification ofMeretricis concha, which is a commonly used marine traditional Chinese med...The goal of this paper is to explore the relationship between the inorganic elemental fingerprint and the geographical origin identification ofMeretricis concha, which is a commonly used marine traditional Chinese medicine (TCM) for the treatment of asthma and scald bums. For that, the inorganic elemental contents ofMeretricis concha from five sampling points in Jiaozhou Bay have been determined by means of inductively coupled plasma optical emission spectrometry, and the comparative investigations based on the contents of 14 inorganic elements (A1, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se and Zn) of the samples from Jiaozhou Bay and the previous reported Rushan Bay were performed. It has been found that the samples from the two bays are ap- proximately classified into two kinds using hierarchical cluster analysis, and a four-factor model based on principle component analysis could explain approximately 75% of the detection data, also linear discriminant analysis can be used to develop a prediction model to distinguish the samples from Jiaozhou Bay and Rushan Bay with accuracy of about 93%. The results of the present investi- gation suggested that the inorganic elemental fingerprint based on the combination of the measured elemental content and chemom- etric analysis is a promising approach for verifying the geographical origin ofMeretricis concha, and this strategy should be valuable for the authenticity discrimination of some marine TCM.展开更多
Sediment samples obtained from the South Mid-Atlantic Ridge were analyzed for the major and trace elements by inductively coupled plasma atomic emission spectroscopy and inductively coupled plasma mass spectrometry. R...Sediment samples obtained from the South Mid-Atlantic Ridge were analyzed for the major and trace elements by inductively coupled plasma atomic emission spectroscopy and inductively coupled plasma mass spectrometry. Results revealed that the contents of elements(e.g., Fe, Mn, Cu, Zn, V, Co) were high in samples 22V-TVG10 and 26V-TVG05 from the sites near the hydrothermal areas, and low in sample 22V-TVG14, which was collected far from the hydrothermal areas. The contents of Ca, Sr and Ba in the samples showed opposite trends. A positive correlation between the concentrations of metallic elements(Cu, Zn, Co, Ni, Pb, V) and Fe in the samples were observed. These results are consistent with chemical evolution of the dispersing hydrothermal plume.展开更多
Self-made enriched IUB boric acid as raw material was purified by recrystallization. The effects of final crystallization temperature, crystallization time, stirring speed, crystallization frequency and other factors ...Self-made enriched IUB boric acid as raw material was purified by recrystallization. The effects of final crystallization temperature, crystallization time, stirring speed, crystallization frequency and other factors on the purity were investigated. The appropriate operating condition was that the final crystallization temperature and time were 5 ℃ and 10 h respectively under a low-speed stirring for crystallizing twice, which would make the purity and yield of boric acid reach 99.94% and 95.36%, respectively. Taking this as foundation, recrystallization process was optimized with acetone as anti-solvent, whose amount was the most important index. The boric acid solution was added into acetone and recrystallized under the same condition, and the purity and yield of boric acid would reach 99.98% and 99.61%, respectively. The product detected by XRD was confirmed as boric acid crystal. Main ion concentration in the product was detected by ICP, which basically met the national standard of high purity. Crystal morphology of boric acid was observed by SEM.展开更多
Surface sediment samples were collected at 21 offshore sites in western Xiamen Bay, Southeast China. Total concentrations of Li, V, Cr, Co, Ni, Cu, Zn, St, Mn, Pb, Ba, Fe, and Ti were determined by inductively coupled...Surface sediment samples were collected at 21 offshore sites in western Xiamen Bay, Southeast China. Total concentrations of Li, V, Cr, Co, Ni, Cu, Zn, St, Mn, Pb, Ba, Fe, and Ti were determined by inductively coupled plasma-optical emission spectrometry; Hg was determined by atomic fluorescence spectrometry. A modified BCR sequential extraction procedure was used to extract fractions of the above elements. Concentrations of Pb, Cr, and Hg at most sites met the primary standard criteria of Marine Sediment Quality except site S12 for Pb and S7 for Cr, while concentrations of Zn at 17 sites and Cu at seven sites exceeded the criteria. The mean concentration of Hg was three times higher than the background, with a possible source being the Jiulong River. Fe, Ti, Ba, Co, V, and Li dominated the residual phase, mainly from terrestrial input. Ni, Cr, Pb, and Hg in the non-residual phase varied largely between sites. Sr, Mn, Cu, and Zn were mainly in the non- residual fraction. Most sites showed considerable ecological risk; exceptions were site S7 (very high) and sites S10, S11, and S14 (moderate). Cu showed moderate-to-high pollution and Pb exhibited no-to-low pollution, while other metals had a non-pollution status according to their ratios of secondary phase to primary phase (RSP). Results of two assessment methods showed moderate pollution and a very high ecological risk for Cu, Zn, Ni, and Cr at site S7, which might be due to the local sewage treatment plant.展开更多
The values of GΘ,EΘ or pH from 110 to 160℃ were calculated and the relevant potential expressions were obtained.E-pH diagrams of ZnS-H2O system at oxygen partial pressure of 0.8 MPa,ionic activity of 1.0 and differ...The values of GΘ,EΘ or pH from 110 to 160℃ were calculated and the relevant potential expressions were obtained.E-pH diagrams of ZnS-H2O system at oxygen partial pressure of 0.8 MPa,ionic activity of 1.0 and different temperatures were drawn through thermodynamical calculation.With the temperature increasing,the stable regions of S and Zn(Ⅱ) in the E-pH diagrams become gradually larger,but the amplification decreases over 150℃.The impacts of leaching parameters,such as temperature,liquid to solid ratio,initial acidic concentration,leaching time,oxygen partial pressure and stirring speed on the leaching rate of Zn(Ⅱ) and conversion rate of S in the single factor of high pressure leaching experiment of ZnS in autoclave,were studied.The leaching residue was examined by X-ray fluorescence(XRF) chemical composition identification and X-ray diffraction(XRD) phase identification,and the content of the leaching solution was tested by inductively coupled plasma-atomic emission spectrometry(ICP).The experimental results indicate that the leaching rate of zinc increases from 60.05% to 97.85% and the conversion rate of sulfur increases from 38.90% to 80.92% with the temperature increasing from 110℃ to 150℃,5:1 of liquid-to-solid ratio,150 g/L of initial acidic concentration,120 min of leaching time,0.8 MPa of oxygen partial pressure,and 480 r/min of stirring speed,which tend to be stable over 150℃.The experimental results correspond with theoretical calculation.展开更多
The effect of dolomite with different particle size fractions on hematite flotation was studied using sodium oleate as collector at p H of about 9. The effect mechanism of dolomite on hematite flotation was investigat...The effect of dolomite with different particle size fractions on hematite flotation was studied using sodium oleate as collector at p H of about 9. The effect mechanism of dolomite on hematite flotation was investigated by means of solution chemistry, ultraviolet spectrophotometry(UV), inductively coupled plasma atomic emission spectrometry(ICP-AES) and X-ray photoelectron spectroscopy(XPS). It is observed that dolomite with different size fractions has depressing effect on hematite flotation using sodium oleate as collector, and dolomite could be the "mineral depressant" of hematite using sodium oleate as collector. The reasons for that are concerned with sodium oleate consumption and the adsorption onto hematite of dissolved species of dolomite.展开更多
We have developed a compact photoelectron imaging facility, including an anion source with dissociative photoelectron attachment to molecules, a linear time-of-flight mass spec-trometry (TOFMS), and an orthogonal hi...We have developed a compact photoelectron imaging facility, including an anion source with dissociative photoelectron attachment to molecules, a linear time-of-flight mass spec-trometry (TOFMS), and an orthogonal high-resolution threshold photoelectron velocity map imaging spectrometer (VMI). Intense and cold cluster anions were prepared in photoelectron- attachment processes upon pulsed UV laser ablation of metal target. Combining this anion source with TOFMS-VMI, the achieved mass resolution is about 200, and the electron ki- netic energy resolution is better than 3%, i.e., 30 meV for 1 eV electrons. More importantly, low-energy photoelectron imaging spectra for CH3S- and S2- at 611.46 nm are obtained. In both cases, the refined electron affinities are determined to be 1.86264-0.0020 eV for CH3S and 1.67444-0.0035 eV for S2, respectively. Preliminary results suggest that the apparatus is a powerful tool for estimating precise electron affinities values from threshold photoelectron imaging spectroscopy.展开更多
Heavy metal determination was carried out by applying the solid phase extraction (SPE) method in batch mode followed by atomic absorption spectroscopy (AAS) and inductively coupled plasma atomic emission spectrosc...Heavy metal determination was carried out by applying the solid phase extraction (SPE) method in batch mode followed by atomic absorption spectroscopy (AAS) and inductively coupled plasma atomic emission spectrosco py (ICP-AES) from aqueous solutions using Ghezeljeh montmorillonite nanoclay as a new natural adsorbent. The Ghezeljeh clay is characterized by using Fourier Transform Infrared (FT-IR) Spectroscopy, Scanning Electron Mi- croscopy-Energy Dispersive Spectrometry (SEM-EDS) and X-ray Diffractometry (XRD) and X-ray Fluorescence (XRF). The results of XRD and FT-IR of nanoclay confirm that montmorillonite is the dominant mineral phase. Based on SEM images of Ghezeljeh clay, it can be seen that the distance between the plates is Nano. The effects of varying parameters such as initial concentration of metal ions, pH and type of buffer solutions, amount of ad- sorbent, contact time, and temperature on the adsorption process were examined. The effect of various interfer- ing ions was studied. The adsorption data correlated with Freundlich, Langmuir, Dubinin-Radushkevich (D-R), and Temkin isotherms. The Langmuir and Freundlich isotherms showed the best fit to the equilibrium data for Hg(II), but the equilibrium nature of Cu(ll) adsorption has been described by the Langmuir isotherm. The kinetic data were described with pseudo-first-order, pseudo-second-order and double-exponential models, The adsorp- tion process follows a pseudo-second-order reaction scheme, Calculation of AGσ, △Hσ and ASσ showed that tilenature of Hg(II) ion sorption onto the Ghezeljeh nanoclay was endothermic and was favored at higher temper- attire, and the nature of Cu(II) ion sorption was exothermic and was favored at lower temperature,展开更多
The effects of Fe2+ on the trimethylamine N-oxide (TMAO) demethylating activity of the Harpadon nehereus kidney extract were studied in this research.The activity of the kidney extract was presumably inhibited by ethy...The effects of Fe2+ on the trimethylamine N-oxide (TMAO) demethylating activity of the Harpadon nehereus kidney extract were studied in this research.The activity of the kidney extract was presumably inhibited by ethylene diamine tetra-acetic acid (EDTA),which indicates that the kidney extract contains an enzyme or enzyme system with metal cations as activator.Activity of the kidney extract was enhanced significantly when Fe2+ was added into the model system in vitro.As the concentration of Fe2+ increased,the decomposing rate of TMAO increased rapidly until TMAO decomposed completely.The activity of the kidney extract was also enhanced by reductant such as ascorbic acid.Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) was employed to determine the content of total iron in a number of fishery products.Significant positive correlation between the contents of total iron and endogenous formaldehyde (FA) was found,especially in marine products.展开更多
A series of tungsten-substituted molybdophosphoric acids(H3PMo12-nWnO40·xH2O) were synthesized and characterized by inductive coupled plasma atomic emission spectroscopy(ICPAES),thermal gravimetry and differentia...A series of tungsten-substituted molybdophosphoric acids(H3PMo12-nWnO40·xH2O) were synthesized and characterized by inductive coupled plasma atomic emission spectroscopy(ICPAES),thermal gravimetry and differential scanning calorimetry(TG-DSC),Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),and FTIR pyridine adsorption.The as-prepared heteropoly acids have a Keggin type structure.The synthesis of tetrahydrofuran by reactive distillation and cyclodehydration of 1,4-butanediol was studied using the tungsten-substituted molybdophosphoric acids as catalysts.The results of catalytic test indicated that the catalytic activity increased with the increase in the substitution number(n) of tungsten atom in H3PMo12-nWnO40·xH2O and was constant as the substitution number(n) was more than 8.The catalytic activity increased with the increase in the catalyst loading and the selectivity of tetrahydrofuran was nearly 100%.展开更多
文摘In order to build method for measuring of elements in honey, the contents of Ba, Cu, Pb, Cd, As, Hg, Cr, Mn, Se had been determined by microwave diges- tion (MWD) and actively coupled plasma atomic emission spectrometry (ICP-AES). The results show that, the range of heavy metal elements were in the range of 0- 10.0 mg/L, with good linear relationship. In addition, all correlation coefficients kept higher than 0.999, and the recovery rate of ample added with standard solution was in 94.1%-110%. By comparison with the result of chemical experiment, the method was quickly accessible and convenient, widely used in the measurement of elements in honey, with satisfactory results.
文摘In order to develop a method for measuring of elements in Sipunculus nudus, the contents of Cu, Pb, Cd, Cr, Mn, As, Hg and Ba were determined by actively coupled plasma atomic emission spectrometry (MWD) and microwave digestion (ICP-AES). The results showed that correlation coefficients al kept higher than 0.999 and the recovery rates of sample added standard solutions were in 98%-114%. The results indicated that the contents of Cu, Pb, Cd, Cr, Mn, As, Hg and Ba were 17.119, 3.781, 0.695, 7.351, 1997.982, 0.620, 0.144, 4.249 mg/kg respectively. The contents of Mn exceeded national limit by hundredfold, Cd sevenfold, Pd fourfold, Cd three-and-a-half-fold, and As onefold. Sipunculs nudus became seriously pol uted. Therefore, it is necessary to formulate robust policies to fol ow closely and pay close attention to coastal areas pol ution around Dongfang City.
文摘Cadmium (Cd) concentrations in the water extracts of ten contaminated soils by arsenic (As) with various iron (Fe) contents were measured using inductively coupled plasma atomic emission spectrometry (ICP-AES) and electrothermal atomic absorption spectrometry (ETAAS), Due to the potential spectral interferences of As and Fe in the quantification of Cd, two methods were used for the background compensation. The first method was based on the use of a deuterium lamp (BGCD2 mode). The second one required a Cd hollow cathode lamp pulsated with a current for which the intensity varies in the course of time (BGCSR mode). The results showed that the choices of the analytical technique and the method used for the background compensation depend on the Cd, As and Fe concentrations in the solution and the concentration ratios As/Cd or/and Fe/Cd. In comparison with the ICP-AES and the ETAAS in combination with the BGCD2 mode, it was shown that the high-speed self-reversal method (HSSR) was a more appropriate method to correct As and Fe spectral interferences during the Cd measurements. On the other hand, depending on the Cd concentration, it was established that no significant Fe interference occurred during the Cd determination even if Fe concentration was 50 mg/L, reflecting the efficiency of the HSSR method to overcome the Fe interferences in the determination of Cd concentration by ETAAS without any matrix modifier in water extracts.
基金supposed by the Program for Science and Technology of Shandong Province (2011GHY11521)the Department of Education of Shandong Province (No. J11LB07)the Natural Science Foundation of Qingdao City (Nos. 12-1-3-52-(1)-nsh and 12-1-4-16-(7)-jch)
文摘Meretricis concha is a kind of marine traditional Chinese medicine(TCM), and has been commonly used for the treatment of asthma and scald burns. In order to investigate the relationship between the inorganic elemental fingerprint and the geographical origin identification of Meretricis concha, the elemental contents of M. concha from five sampling points in Rushan Bay have been determined by means of inductively coupled plasma optical emission spectrometry(ICP-OES). Based on the contents of 14 inorganic elements(Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se, and Zn), the inorganic elemental fingerprint which well reflects the elemental characteristics was constructed. All the data from the five sampling points were discriminated with accuracy through hierarchical cluster analysis(HCA) and principle component analysis(PCA), indicating that a four-factor model which could explain approximately 80% of the detection data was established, and the elements Al, As, Cd, Cu, Ni and Pb could be viewed as the characteristic elements. This investigation suggests that the inorganic elemental fingerprint combined with multivariate statistical analysis is a promising method for verifying the geographical origin of M. concha, and this strategy should be valuable for the authenticity discrimination of some marine TCM.
基金supported by the National Natural Science Foundation of China(No.51273184)the National Natural Science Foundation of China Shandong Joint Fund for Marine Science Research Centers(No.U1406402)
文摘The goal of this paper is to explore the relationship between the inorganic elemental fingerprint and the geographical origin identification ofMeretricis concha, which is a commonly used marine traditional Chinese medicine (TCM) for the treatment of asthma and scald bums. For that, the inorganic elemental contents ofMeretricis concha from five sampling points in Jiaozhou Bay have been determined by means of inductively coupled plasma optical emission spectrometry, and the comparative investigations based on the contents of 14 inorganic elements (A1, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se and Zn) of the samples from Jiaozhou Bay and the previous reported Rushan Bay were performed. It has been found that the samples from the two bays are ap- proximately classified into two kinds using hierarchical cluster analysis, and a four-factor model based on principle component analysis could explain approximately 75% of the detection data, also linear discriminant analysis can be used to develop a prediction model to distinguish the samples from Jiaozhou Bay and Rushan Bay with accuracy of about 93%. The results of the present investi- gation suggested that the inorganic elemental fingerprint based on the combination of the measured elemental content and chemom- etric analysis is a promising approach for verifying the geographical origin ofMeretricis concha, and this strategy should be valuable for the authenticity discrimination of some marine TCM.
基金the National Natural Science Foundation of China (No. 41306053)the Open Fund of the Key Laboratory of Marine Geology and Environment, Chinese Academy of Sciences (Nos. MGE 2015KG04 and MGE2015KG01)+2 种基金the Open Fund of the Key Laboratory of Submarine Geosciences, State Oceanic Administration, People’s Republic of China (No. KSLG 1503)the Special Fund for the Taishan Scholar Program of Shandong Province (No. ts201511061)The authors would like to thank the crews of the COMRA cruises (DY115-22 and DY115-26)
文摘Sediment samples obtained from the South Mid-Atlantic Ridge were analyzed for the major and trace elements by inductively coupled plasma atomic emission spectroscopy and inductively coupled plasma mass spectrometry. Results revealed that the contents of elements(e.g., Fe, Mn, Cu, Zn, V, Co) were high in samples 22V-TVG10 and 26V-TVG05 from the sites near the hydrothermal areas, and low in sample 22V-TVG14, which was collected far from the hydrothermal areas. The contents of Ca, Sr and Ba in the samples showed opposite trends. A positive correlation between the concentrations of metallic elements(Cu, Zn, Co, Ni, Pb, V) and Fe in the samples were observed. These results are consistent with chemical evolution of the dispersing hydrothermal plume.
文摘Self-made enriched IUB boric acid as raw material was purified by recrystallization. The effects of final crystallization temperature, crystallization time, stirring speed, crystallization frequency and other factors on the purity were investigated. The appropriate operating condition was that the final crystallization temperature and time were 5 ℃ and 10 h respectively under a low-speed stirring for crystallizing twice, which would make the purity and yield of boric acid reach 99.94% and 95.36%, respectively. Taking this as foundation, recrystallization process was optimized with acetone as anti-solvent, whose amount was the most important index. The boric acid solution was added into acetone and recrystallized under the same condition, and the purity and yield of boric acid would reach 99.98% and 99.61%, respectively. The product detected by XRD was confirmed as boric acid crystal. Main ion concentration in the product was detected by ICP, which basically met the national standard of high purity. Crystal morphology of boric acid was observed by SEM.
基金supported by the National Natural Science Foundation of China(21177043,21077036)+1 种基金State Key Laboratory of Environmental Geochemistry(SKLEG2013801)Cultivation Project on 2014 Postgraduates’Research and Innovation Capability of Huaqiao University(426)
文摘Surface sediment samples were collected at 21 offshore sites in western Xiamen Bay, Southeast China. Total concentrations of Li, V, Cr, Co, Ni, Cu, Zn, St, Mn, Pb, Ba, Fe, and Ti were determined by inductively coupled plasma-optical emission spectrometry; Hg was determined by atomic fluorescence spectrometry. A modified BCR sequential extraction procedure was used to extract fractions of the above elements. Concentrations of Pb, Cr, and Hg at most sites met the primary standard criteria of Marine Sediment Quality except site S12 for Pb and S7 for Cr, while concentrations of Zn at 17 sites and Cu at seven sites exceeded the criteria. The mean concentration of Hg was three times higher than the background, with a possible source being the Jiulong River. Fe, Ti, Ba, Co, V, and Li dominated the residual phase, mainly from terrestrial input. Ni, Cr, Pb, and Hg in the non-residual phase varied largely between sites. Sr, Mn, Cu, and Zn were mainly in the non- residual fraction. Most sites showed considerable ecological risk; exceptions were site S7 (very high) and sites S10, S11, and S14 (moderate). Cu showed moderate-to-high pollution and Pb exhibited no-to-low pollution, while other metals had a non-pollution status according to their ratios of secondary phase to primary phase (RSP). Results of two assessment methods showed moderate pollution and a very high ecological risk for Cu, Zn, Ni, and Cr at site S7, which might be due to the local sewage treatment plant.
基金Project (2007CB613504) supported by the National Basic Research Program of ChinaProject(20050145029) supported by the PhD Programs Foundation of Ministry of Education of ChinaProject(2005221012) supported by the Science and Technology Talents Fund for Excellent Youth of Liaoning Province, China
文摘The values of GΘ,EΘ or pH from 110 to 160℃ were calculated and the relevant potential expressions were obtained.E-pH diagrams of ZnS-H2O system at oxygen partial pressure of 0.8 MPa,ionic activity of 1.0 and different temperatures were drawn through thermodynamical calculation.With the temperature increasing,the stable regions of S and Zn(Ⅱ) in the E-pH diagrams become gradually larger,but the amplification decreases over 150℃.The impacts of leaching parameters,such as temperature,liquid to solid ratio,initial acidic concentration,leaching time,oxygen partial pressure and stirring speed on the leaching rate of Zn(Ⅱ) and conversion rate of S in the single factor of high pressure leaching experiment of ZnS in autoclave,were studied.The leaching residue was examined by X-ray fluorescence(XRF) chemical composition identification and X-ray diffraction(XRD) phase identification,and the content of the leaching solution was tested by inductively coupled plasma-atomic emission spectrometry(ICP).The experimental results indicate that the leaching rate of zinc increases from 60.05% to 97.85% and the conversion rate of sulfur increases from 38.90% to 80.92% with the temperature increasing from 110℃ to 150℃,5:1 of liquid-to-solid ratio,150 g/L of initial acidic concentration,120 min of leaching time,0.8 MPa of oxygen partial pressure,and 480 r/min of stirring speed,which tend to be stable over 150℃.The experimental results correspond with theoretical calculation.
基金Project(51374079)supported by the National Natural Science Foundation of ChinaProject(KKSY201521031)supported by Talent Cultivation Foundation of Kunming University of Science and Technology,ChinaProject(2015Y067)supported by Foundation of Yunnan Educational Committee,China
文摘The effect of dolomite with different particle size fractions on hematite flotation was studied using sodium oleate as collector at p H of about 9. The effect mechanism of dolomite on hematite flotation was investigated by means of solution chemistry, ultraviolet spectrophotometry(UV), inductively coupled plasma atomic emission spectrometry(ICP-AES) and X-ray photoelectron spectroscopy(XPS). It is observed that dolomite with different size fractions has depressing effect on hematite flotation using sodium oleate as collector, and dolomite could be the "mineral depressant" of hematite using sodium oleate as collector. The reasons for that are concerned with sodium oleate consumption and the adsorption onto hematite of dissolved species of dolomite.
文摘We have developed a compact photoelectron imaging facility, including an anion source with dissociative photoelectron attachment to molecules, a linear time-of-flight mass spec-trometry (TOFMS), and an orthogonal high-resolution threshold photoelectron velocity map imaging spectrometer (VMI). Intense and cold cluster anions were prepared in photoelectron- attachment processes upon pulsed UV laser ablation of metal target. Combining this anion source with TOFMS-VMI, the achieved mass resolution is about 200, and the electron ki- netic energy resolution is better than 3%, i.e., 30 meV for 1 eV electrons. More importantly, low-energy photoelectron imaging spectra for CH3S- and S2- at 611.46 nm are obtained. In both cases, the refined electron affinities are determined to be 1.86264-0.0020 eV for CH3S and 1.67444-0.0035 eV for S2, respectively. Preliminary results suggest that the apparatus is a powerful tool for estimating precise electron affinities values from threshold photoelectron imaging spectroscopy.
基金financial support for this work by the Imam Khomeini International University (IKIU)Mines and Mining Industries Development and Renovation Organization of Iran (IMIDRO)
文摘Heavy metal determination was carried out by applying the solid phase extraction (SPE) method in batch mode followed by atomic absorption spectroscopy (AAS) and inductively coupled plasma atomic emission spectrosco py (ICP-AES) from aqueous solutions using Ghezeljeh montmorillonite nanoclay as a new natural adsorbent. The Ghezeljeh clay is characterized by using Fourier Transform Infrared (FT-IR) Spectroscopy, Scanning Electron Mi- croscopy-Energy Dispersive Spectrometry (SEM-EDS) and X-ray Diffractometry (XRD) and X-ray Fluorescence (XRF). The results of XRD and FT-IR of nanoclay confirm that montmorillonite is the dominant mineral phase. Based on SEM images of Ghezeljeh clay, it can be seen that the distance between the plates is Nano. The effects of varying parameters such as initial concentration of metal ions, pH and type of buffer solutions, amount of ad- sorbent, contact time, and temperature on the adsorption process were examined. The effect of various interfer- ing ions was studied. The adsorption data correlated with Freundlich, Langmuir, Dubinin-Radushkevich (D-R), and Temkin isotherms. The Langmuir and Freundlich isotherms showed the best fit to the equilibrium data for Hg(II), but the equilibrium nature of Cu(ll) adsorption has been described by the Langmuir isotherm. The kinetic data were described with pseudo-first-order, pseudo-second-order and double-exponential models, The adsorp- tion process follows a pseudo-second-order reaction scheme, Calculation of AGσ, △Hσ and ASσ showed that tilenature of Hg(II) ion sorption onto the Ghezeljeh nanoclay was endothermic and was favored at higher temper- attire, and the nature of Cu(II) ion sorption was exothermic and was favored at lower temperature,
基金supported by the National Natural Science Foundation of China (No.30871949)
文摘The effects of Fe2+ on the trimethylamine N-oxide (TMAO) demethylating activity of the Harpadon nehereus kidney extract were studied in this research.The activity of the kidney extract was presumably inhibited by ethylene diamine tetra-acetic acid (EDTA),which indicates that the kidney extract contains an enzyme or enzyme system with metal cations as activator.Activity of the kidney extract was enhanced significantly when Fe2+ was added into the model system in vitro.As the concentration of Fe2+ increased,the decomposing rate of TMAO increased rapidly until TMAO decomposed completely.The activity of the kidney extract was also enhanced by reductant such as ascorbic acid.Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) was employed to determine the content of total iron in a number of fishery products.Significant positive correlation between the contents of total iron and endogenous formaldehyde (FA) was found,especially in marine products.
基金Supported by Research Funds from Chinese Education Department (2003406)Bureau of Science and Technology of Jiangsu Province (BG2006025)
文摘A series of tungsten-substituted molybdophosphoric acids(H3PMo12-nWnO40·xH2O) were synthesized and characterized by inductive coupled plasma atomic emission spectroscopy(ICPAES),thermal gravimetry and differential scanning calorimetry(TG-DSC),Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),and FTIR pyridine adsorption.The as-prepared heteropoly acids have a Keggin type structure.The synthesis of tetrahydrofuran by reactive distillation and cyclodehydration of 1,4-butanediol was studied using the tungsten-substituted molybdophosphoric acids as catalysts.The results of catalytic test indicated that the catalytic activity increased with the increase in the substitution number(n) of tungsten atom in H3PMo12-nWnO40·xH2O and was constant as the substitution number(n) was more than 8.The catalytic activity increased with the increase in the catalyst loading and the selectivity of tetrahydrofuran was nearly 100%.