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Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geology & Exploration is the property of Geology & Exploration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

PM2. 5 components of Yingtan City were continuously monitored for 29 days using XRF online analyzer, oc/ec online analyzer and ion chromatography online analyzer. The daily average concentration of PM2. 5 at the monitoring site during spring monitoring period ranged from 6 to 49 μg/m~3,with an average concentration 30. 7 μg/m~3. The daily average concentration of PM2. 5 was between 16～50 μg/m~3,and the average concentration was 37. 5 μg/m~3 during winter monitoring. The concentration levels and daily variation characteristics of eight heavy metal elements were analyzed, and the sources and pollution levels of these elements were assessed. Additionally, the elemental exposure doses were calculated, and health risk assessments were conducted. The results were shown as follows:（1）During the monitoring period, the average concentrations of Cr and other elements in spring PM2. 5 were lower than those in winter PM2. 5. The mass concentrations of Cu and Zn in winter were significantly higher than those in other cities, which may be related to the accumulation of emissions from the copper smelting and processing industry in Yingtan City;（2）The ambient air PM2. 5 in Yingtan City in spring was slightly enriched with Cr, Mn, Ni, Cu, Zn, As, Pb and Cd. In winter, Mn was slightly enriched, Cr and Ni were moderately enriched, and Cu, Zn, As, Cd and Pb were highly enriched. （3）The results of principal factor analysis showed that the proportion of soil dust and crust dust from natural sources in spring and winter were 38. 0% and 35. 2% respectively, making them the largest single source of PM2. 5 in Yingtan City. （4）The exposure dose shows that the daily average exposure level of 8 elements in PM2. 5 were ADDing＞ADDinh＞ADDderm, and ADDing was much higher than ADDinh and ADDderm. Among the three exposure pathways, children had the highest exposure doses for all eight elements. Among the 8 elements, Zn has the highest exposure dose to different populations under different exposure pathways, with ADDing in children being 0. 038 0,ADDing in adult males being 0. 010 3,and ADDing in adult females being 0. 011 8 [mg·（kg·d）-1]. （5）The health risk assessment results indicated that As posed a certain non carcinogenic health risk to all populations and Pb has a certain non carcinogenic health risk for children. The sum of the non carcinogenic risk values of the 8 elements showed the following order: ADDing＞ADDderm＞ADDinh, with ADDing being the main pathway for non carcinogenic risk. None of the 8 elements had a carcinogenic risk to the exposed population. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geology & Exploration is the property of Geology & Exploration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Northwest A & F University - Natural Science Edition is the property of Editorial Department of Journal of Northwest A&F University (Natural Science Edition) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chinese Institute of Food Science & Technology / Zhongguo Shipin Xuebao is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to accurately quantify the trace elements in the ant, the samples were pretreated by microwave digestion with HNO3-H2O2 mixed acid as the digestion system. The appropriate isotopes were selected. 52Cr, 55Mn, 60Ni, 63Cu, 66Zn, 75As, 78Se, 88Sr and 114Cd were determined with 103Rh as internal standard. 202Hg and 208Pb were determined with 185Re as internal standard. Then a method for the determination of 11 trace elements in polyrhachis vicina rogers by inductively coupled plasma mass spectrometry was established. It was found that the sample was completely digested with HNO3-H2O2 as the digestion system. KED mode was used to eliminate the interference of mass spectrometry, and the matrix effect was corrected by internal standard method. By drawing the calibration curve and determining the blank of the process, the correlation coefficient of the calibration curve of each element was greater than 0.999, the detection limit of the method was 0.000 5-0.011 mg/kg, and the quantitative limit of the method was 0.001 6-0.033 mg/kg. The actual samples of Polyrhachis vicina rogers were determined. The relative standard deviations (RSD, n = 9) were in the range of 1.2%-5.5%, and the recoveries were 91.2%-107%. Through the comparison test between laboratories, the relative deviations were between - 3.15% and 2.74%. The samples of polyrhachis vicina roger from six different habitats were determined. The results showed that there were great differences in the contents of other 10 trace elements except cadmium in samples from different habitats. Results were stable and reliable, and could meet the requirements for the analysis and detection of 11 trace metal elements in Polyrhachis vicina roger. [ABSTRACT FROM AUTHOR]

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective Aiming at the corrosion problem of carbon steel weld in the produced water environment of a gas field, trace metal elements such as Mo, Cr, Ni and Cu were added to microalloying the electrode. Method The corrosion resistances of five kinds of carbon steel weld metals with different structures were systematically evaluated by immersion corrosion method at 60 ℃ in the produced water of gas field. Result The addition of Mo and Cr elements can refine the grains and improve the corrosion resistance. Conclusions By adding 12 wt% Cr, 1.5 wt% Ni, 1.6 wt% Mo and 0.8 wt% Cr, 0.3 wt% Ni, 0.3 wt% Cu into the electrode, the electrochemical corrosion resistance of the weld structure can be improved. The corrosion products are mainly composed of FeCO3, and some samples also contain a small amount of FeS or FeS2 and CaCO3. [ABSTRACT FROM AUTHOR]

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A method for the determination of eight metal elements in silicon manganese smelting slag by inductively coupled plasma mass spectrometry (ICP-MS) was established by using HCl-HNO3-HF-HClO4 mixed acid as digestion system, adding 1. 0 mL of 100 g/L hydroxylamine hydrochloride solution to dissolve the residue, s electing appropriate isotopes, and using 103 Rh as internal standard to determine Cr, Co, Ni, Cu, Zn and Cd, and 193Ir as internal standard to determine Tl and Pb. It was found that the sample pretreatment selection HC1 : HNO3 : HF : HClO4 = 5 : 5 : 5 : 1, and 1.0 mL 100 g/L hydroxylamine hydrochloride solution was added in the redissolution stage to completely digest the sample. The determination results of the elements to be determined in the sample were not interfered by the matrix composition. The KED mode and interference coefficient correction method were used to eliminate the interference of mass spectrometry. By drawing the calibration curve and measuring the bank of the process, the correlation coefficients of each element calibration curve were all greater than 0. 999 9. The detection Units were between 0. 006 mg/kg and 0. 19 mg/kg. The limits of quantification were between 0. 018 mg/kg and 0. 57 mg/kg. The actual sampes of silicomanganese stag were determined, the relative standard deviations (RSD, n = 11) were in the range of 0.83%--4.1%, and the recoveries were 94.7%--106%. After personnel comparison test, the relative deviation was between --4. 54% and 4. 24%. The results showed that the method was stable and reliable and could meet the requirements of analysis and detection of eight trace metal elements in silicon manganese smelting stag. [ABSTRACT FROM AUTHOR]

A method for the simultaneous determination of tungsten, molybdenum, thalium, cadmium, bismuth, uranium, thorium, and chromium in phosphate ore samples by inductively coupled plasma mass spectrometry after open wet digestion system of mixed four acid (nitric acid-hydrofluoric acid-perchloric acid-sulfuric acid) was established. Satisfactory and accuracy results were obtained compared with the classic alkaline solution method. The effect of volatile and insoluble elements in phosphate ores was dsscussed. Appropriate analytical isotopes were seated and interference correction equations were used to eliminate mass interference. Using 103Rh and 186Re as internal standard elements, the dynamic drift of the analysis signal was effectively corrected. The detection limit is 0. 010-0. 36 µg/g, the precision is less than 6%, and the recovery is between 93. 4% -108%. Without increasing the analysis cost, sample solution can also be used for the determination of other major and trace elements by ICP-OES and ICP-MS at the same time. The method is simple, fast, practical, and suitable for the detection of 8 elements in phosphate ores. [ABSTRACT FROM AUTHOR]

The weak mass number difference of interference elements and target elements can be distinguished by high resolution coupled plasma mass spectrometry which can solve the mass spectrometry of polyatoms and oxides. It has been focused on trace element analysis in coal, but the application is still not mature enough. The challenge of mass spectrometry interference in determination of trace metal elements, especially rare earth elements in coal has not been systematically reported. HNO3-HF mixed acid was used to digest coal sample, pretreatment conditions such as digestion time, evaporation acid and resolution were optimized. The mass spectrometry interference of V, Cr, Mn, Co, Ni, Cu, Ga, Ge, As, Rb, Sr, Y, Nb, Mo, Cd, Sn,Sb,Cs,Ba,La,Ce,Pr,Nd,Sm,Eu,Dy,Gd,Tb, Ho,Er,Lu, Hf,Tl,Pb,Th total 35 trace metal elements at low, midde and high resolution was studied. Ge, Nd, Eu, Gd, Ho, Er, Lu were determined in high resolution pattern, Ga was determined in mid-resolution pattern, the remaining elements were determined in low resolution pattern. A method for measuring 35 trace metal elements in coal with high resolution inductively coupled plasma mass spectrometry was established. Under the optimized experimental conditions, the linear correlation coefficient of each element standard curve is greater than 0.999 9, and the detection limit is 0. 001--0. 082 µg/g. Coal standard sample (SARM 20) was selected for method verification, and elements with no certified value in the standard sample were basically matched with the standard experiment, the relative standard deviation of determination results are 0. 27c--6. 3% and the standard recoveries are 85. 8%-- 117 Four representative sample of other bituminous coal from Russian, other bituminous coal from Australian, coking coal from Mongolian, and other bituminous coal from Indonesia were seeded for testing, and the differences of trace metal element contents in coal from different producing areas were analyzed. The centents of Mn,Ba,Sr and rare earth elements are different in four coals, which can support the analysis of coal origin. [ABSTRACT FROM AUTHOR]

BACKGROUND: The toxic and hazardous elements in manganese ore not only affect manganese purification, production environment and product quality, but have also always been a technical problem in the manganese industry and particularly in experimental testing. At present, there are a total of 10 existing manganese ore composition analysis standard materials in the world, all of which lack the certified values of harmful components such as Cl, F, Co, Cr, Hg and As. Therefore, they do not meet the needs of manganese purification research, environmental monitoring, manganese ore import and detection method research. OBJECTIVES: To prepare manganese ore composition analysis standard materials with quantitative values for Cl, F, As, Pb, Cd, Cr and Hg. METHODS: Two certified chemical composition reference materials of manganese ore (GBW07139, GBW07140) were prepared by collecting samples from 3 large-scale manganese mining areas in Hunan Province and Xinjiang Autonomous Region. According to the type of deposit, all the samples passed the 97μm standard sieve and the initial uniformity inspection, and were packed into the smallest packaging unit individually or in combination. RESULTS: For the uniformity test of randomly selected 2×30 bottles, the measured values of F were all less than F0.05（29,60）=1.59, and the relative standard deviation was between 0.45% and 6.44%, indicating good uniformity of the samples. The long-term stability/short-term stability test was carried out within one year, and the linear model/average consistency data showed no significant difference, indicating good stability of samples. Ten laboratories participated in the collaborative certified value research, which included 23 components such as Mn, MnO2, SiO2, Al2O3, Fe, CaO, MgO, K2O, Na2O, TiO2, S, P, Cu, Co, Zn, Ni, Pb, Cd, Hg, Cr, As, Cl and F. In the two manganese ore composition analysis standard materials, the mass fractions of Mn were 21.63% and 41.55%, Cl were 38×10-6 and 1214×10-6, Ni were 1075×10-6 and 30.9×10-6, respectively. CONCLUSIONS: This batch of manganese ore composition analysis standard materials contain certified values of Cl, F, Pb, Cd, Cr, Co, Hg and As, and is suitable for quality control of manganese-related analysis and testing. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Contemporary Pediatrics is the property of Xiangya Medical Periodical Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mycosystema is the property of Mycosystema Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biogas slurry is the liquid part of anaerobic fermentation of excrements from breeding industries. It is rich in organic matters, nitrogen, phosphorus, potassium, and other nutrients. However, biogas slurry is an environmental pollution source if it is discharged without proper treatment. To recover the nutrients and remove Suspended Solids (SS) and trace heavy metals in the biogas slurry, a membrane filtration system was designed in this work. Herein, Ceramic Membrane (CM) was applied for pretreatment because of its large membrane flux, strong anti-pollution ability and high chemical stability features. The key parameters that affect the performance of the membrane filtration system, such as membrane pore size, biogas slurry temperature, membrane surface velocity and Volume Reduction Factor (VRF), were investigated. The effects of pretreatment were studied via analyzing the membrane flux, Chemical Oxygen Demand (COD), turbidity, ammonia nitrogen, and the content of heavy metals under different conditions. The results showed that the membrane flux could reach 250 L/ (m² ·h) for 50 nm CM, which was 75 L/ (m² ·h) higher than that of 20 nm CM. However, in order to achieve high permeate water quality and heavy metal removal efficiency, ultrafiltration by 20 nm pore size CM was selected for pretreatment. The membrane flux increased from 165 to 275 L/ (m² ·h) upon increasing liquid temperature from 15 to 40 °C. With the increase of membrane surface velocity, the membrane flux increased gradually, but the increasing rate decreased. The membrane flux could reach 175 L/ (m² ·h) under the membrane surface velocity of 3.0 m/s.When the concentration rate increased, the membrane fluxes showed a downward trend of first fast and then slow. The maximum VRF of 20 nm pore CM could reach above 10, and the corresponding membrane flux was 62.6 L/ (m2 ·h). The pretreatment of biogas slurry by CM filtration had the optimal economy, when the frequency converter operated in the range of 40-45 Hz. The removal efficiency of turbidity by 20, 100 and 1 000 nm pore CMs was 99.77%, 83.91% and 81.87%, respectively. And there was no significant difference on the COD removal between 20 nm and 100 nm, which was 15.97% and 13.12%, respectively. There was almost no retention of ammonia nitrogen for all CMs. The removal rate of Ca, Mg, K, P by 20 nm CM was 14.7%, 66.3%, 3.9% and 32.9% respectively. The retention rate of Cu, Zn, Pb, Fe and Mn in biogas slurry by 20 nm CM was 96.0%, 95.5%, 100%, 86.5% and 76.0%, respectively. However the removal efficiency of Cr was quite low owing to its anionic state in biogas slurry. To draw a conclusion, pretreatment of biogas slurry by ultrafiltration using 20 nm CM could effectively remove SS and heavy metals, and retain majority of the dissolved organic and inorganic nutrients in biogas slurry. After pretreatment by ultrafiltration, nanofiltration(NF) or reverse osmosis(RO) could be used to concentrate the dissolved nutrients including organic matters, nitrogen, phosphorus, and potassium. This study provides a useful reference for the harmless treatment and resource utilization of swine wastewater and biogas slurry. It is anticipated that membrane concentrate system could render versatile applications for biogas slurry. [ABSTRACT FROM AUTHOR]

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Owing to their small particle size, good stability against photobleaching, high fluorescence stability, tunable fluorescence emission, easy surface functionalization, low toxicity and excellent biocompatibility, carbon dot (CD) has been widely applied in many fields including catalyst, cell imaging, drug delivery, fluorescence detection and photoelectronic devices. In recent years, synthetic methods for preparing high-performance fluorescent CD using different raw materials have attracted much attention. In addition, detection of trace metal ions by a fluorescent probe has been rapidly developed and widely used. The fluorescent probe can be constructed thus:the CD directly interact with the target analyte, the CD modified by the specific ligand interact with the target analyte, and the CD forming a complex with other substances interact with the target analyte. OBJECTIVES: To provide references for researchers to synthesize CD and construct fluorescent probes based on CD for the determination of trace metal ions in complex samples. METHODS: The optical properties and synthetic raw materials of CD were described. The process and characteristics of the commonly used top-down and bottom-up methods were summarized. The application progress of fluorescent probes constructed by the three interaction modes between CD and target analytes for the determination of biochemical reaction ions, Fe3+, Zn2+ and Cu2+, and other heavy metal ions such as Hg2+, As3+, Pb2+, Cr6+ and Cd2+ were reviewed. RESULTS: Different raw materials had been utilized for synthesizing CD with different properties. The prepared CD were used to construct fluorescent probes for the determination of micro metal ions with high selectivity and sensitivity. CONCLUSIONS: Further research on the determination mechanisms, development of new detection modes, construction of fluorescent probes for specific metal ions and sample components, and establishment of analytical methods, which can be applied to complex samples are the challenges and development orientation of the fluorescent probes based on CD. [ABSTRACT FROM AUTHOR]

Copyright of Research of Environmental Sciences is the property of Research of Environmental Sciences Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In view of coal mine waste utilization of trace metal elements in fly ash, using of arbuscular mycorrhizal fungi regulating function of mineral elements, through the reclamation experiment in pot, the different strains of trace element in plant and matrix were compared,which were named Glomus mosseae( G. m) and phosphate-solubilizing bacteria isolated from coal fly ash(CA) and their combined effects. The results show that for the host, inoculated process increases its absorption amount of zinc, iron and copper, while inhibits the excessive absorption of harmful metal elements such as lead and manganese. The mycelium could absorb excess manganese. In different filling thickness comparison, the absorption capacity of zinc, iron and copper by mycorrhizal fungi is better than the root. For the matrix, inoculation could improve the content of zinc,iron,copper and lead,and reduce that of manganese. In compartments process,single abundance and deficiency index of effective zinc, copper and iron of all inoculation treatments are greater than the control. The inoculation treatments could compensate for the impact caused by reducing the thickness of sand in filled reclamation, cost savings. [ABSTRACT FROM AUTHOR]

A static experiment was carried out to evaluate trace cadmium ( II ) removal from water by two kinds of manganese coagulants, hydrous manganese dioxide (HMO) and ferric manganese coagulant (HFMO). The effects of turbidity, initial concentration of cadmium, coagulation time and different waters on the cadmium removal were investigated. The results showed that both HMO and HFMO could eliminate cadmium quickly from water, and the effectiveness of cadmium removed by HMO was better than that by HFMO. When pH = 6. 72, the Cd ( II ) initial concentration was 1 mg/L and the dosage of HMO was 20 mg/L, the removal rate of cadmium reached 85.04%. As for HFMO, when pH = 8.03, the removal rate of cadmium was only 53.23%. HMO performed better than HFMO on removal of cadmium and turbidity, when two manganese coagulants were used to treat the raw water of Jingmi canal of Beijing. [ABSTRACT FROM AUTHOR]

Urban soils are more easily subjected to modification, especially by contamination because of various human activities, and the environmental problems caused by urban soil pollution have become more prominent. To systematically investigate concentration characteristics, pollution levels, and exposure risks of 13 trace metals in urban soils of planning areas for 193 cities above the prefectural level, located in 31 provinces (autonomous regions and municipalities) of China, levels of pollution in urban soil were evaluated using the geoaccumulation index and integrated pollution index of trace metals, and health risks of residents exposed to urban soils were quantified using the health risk assessment method recommended by the US Environmental Protection Agency (USEPA). The results show that the median concentrations of As, Be, Cd, Co, Cr, Cu, Hg, Ni, Pb, Se, Tl, V, and Zn in topsoils of urban planning areas were 9.25, 2.14, 0.174, 12.4, 68.4, 28.2, 0.095, 27.7, 31.1, 0.29, 0.61, 82.7, and 82.2 mg·kg -1 , respectively. Compared with the corresponding urban soil background values, the concentrations of Cd, Hg, and Se changed significantly. The geoaccumulation index ( I ) values showed that Hg in urban soils of the planning area was the most severe pollutant, followed by Se and Cd, which caused pollution levels of uncontaminated to moderately contaminated levels, while other trace metals were uncontaminated. The Nemerow IPI (IPI geo ) values showed that Hg in urban soils of the planning area was the most severe pollutant, followed by Se and Cd, which caused pollution levels of uncontaminated to moderately contaminated levels, while other trace metals were uncontaminated. The Nemerow IPI (IPI N ) revealed that the soils in 22 urban planning areas were heavily polluted and 16 urban planning areas were moderately polluted; in addition, the most polluted city in China was Zhuzhou in the Hunan province. The results of health risk assessment indicate that the soils in the five urban planning areas-Chenzhou City, Huangshi City, Zhuzhou City, Xiangtan City, and Longyan City-posed potential non-carcinogenic risks to children, and the major factor triggering risks was ingestion of Pb. To understand the soil pollution status and distribution of contaminated land parcel, it is suggested to carry out detailed investigation in cities with integrated moderate to heavy pollution to establish the list of contaminated land parcel and implement pollution control and restoration.

Atmospheric trace metal pollution is a striking environmental problem globally. Because of the limitations in monitoring data, our knowledge of the historical processes and sources of atmospheric trace metal pollution in China and its influence on remote terrestrial environmental quality is limited. The historical variations in atmospheric trace metal (Cd, Cr, Cu, Hg, Ni, Pb, and Zn) pollution during the past 400 years in the Fanjing Mountain area, northern Guizhou Province were studied by analyzing the metal concentrations and Pb isotopes in lake sediments. The results showed that concentrations of all metals in the sediments were relatively constant before 1800(A.D.). After 1800, concentrations of Cr, Cu, Ni, and Zn increased at first and then decreased, while concentrations of Hg, Cd, and Pb generally increased gradually over the most recent century and subsequent decades. The enrichment factor and 207 Pb/ 206 Pb analysis results indicated that Cd, Pb, and Hg were typical pollutants. Pollution of Hg began at around 1880(A.D.), and pollution of Cd and Pb has occurred since the 1950s; all pollutants exhibited aggravated trends in recent times. Pollution levels of Hg in recent years in the Fanjing Mountain area were comparable to those in other remote areas of East China, but levels were lower than those in Europe, America, and the Tibetan Plateau. In contrast, pollution levels of Cd and Pb in these areas showed large variability. By comparing the historical processes of trace metal pollution in different regions and exploring the potential pollution sources of metals in the study region, it can be deduced that atmospheric Hg pollution in the Fanjing Mountain area was the result of both global and regional emissions, while Cd and Pb pollution largely came from regional sources such as non-ferrous metals smelting and coal combustion emissions.

To study the pollution characteristics, sources, and transportation process of PM 2.5 and its chemical compositions in the Zhengzhou-Xinxiang region, PM 2.5 samples were collected using a middle volume sampler, in Zhengzhou and Xinxiang urban areas for 30 consecutive days during the winter of 2016. The mass concentration of PM 2.5 was measured gravimetrically. 17 trace metals were determined by inductively coupled plasma-mass spectrometry (ICP-MS), and 7 water-soluble ions were determined by ion chromatography. The enrichment factor (EF) method and principal component analysis were employed to determine the source apportionment. The results showed that the daily mean PM 2.5 mass concentration during the winter sampling period of 2016 in Xinxiang and Zhengzhou was 223.87 μg·m -3 and 226.67 μg·m -3 , respectively, which indicated that pollution levels were relatively high in both cities. The concentration of three macro elements (Al, Ca, and Fe) accounted for 50% of the total metal elements in both cities, while the heavy metals concentration was higher in Xinxiang than in Zhengzhou. The EFs of Cd, Ag, and Pb in Xinxiang were far higher than 1000, while only Cd was higher than 1000 in Zhengzhou. NO 3 - , SO 4 2- , and NH 4 + were the main ions in the two cities. They exceeded 94% of total water-soluble ions and existed in the forms of (NH 4 ) 2 SO 4 and NH 4 NO 3 . The principle component analysis showed that the main contributors to PM 2.5 were a mixture of biomass combustion and secondary aerosol in Xinxiang, and a mixture of coal combustion and traffic emissions in Zhengzhou, accounting for 34.94% and 33.99% of total PM 2.5 emissions, respectively.