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Oxidative Potential of Metal-Containing Nanoparticles in Coal Fly Ash Generated from Coal-Fired Power Plants in China 被引量:3
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作者 Miao Xu Zuoshun Niu +3 位作者 Chang Liu Jia Yan Bo Peng Yi Yang 《Environment & Health》 2023年第3期180-190,共11页
The overwhelming magnitude of coal-fired power plants has caused an inevitable release of metal-containing nanoparticles(MNPs)into the atmosphere,which may be inhaled into the respiratory system and cause oxidative st... The overwhelming magnitude of coal-fired power plants has caused an inevitable release of metal-containing nanoparticles(MNPs)into the atmosphere,which may be inhaled into the respiratory system and cause oxidative stress.In this study,MNPs and oxidative potential(OP)were analyzed in<1μm fractions of 56 coal fly ashes collected from Chinese CFPPs.The particle number concentrations(PNCs)of Fe-and Ti-containing NPs,as the dominant MNPs in CFAs,were in the range of 1.5×10^(9)to 9.4×10^(10)and 6.4×10^(8)to 4.1×10^(10)particles/mg,with average particle sizes of 87 and 89 nm,respectively.Average OP values of<1μm fractions were 1.4−2.2 nmol AA min^(−1)μg^(−1)for three simulated lung fluids,which were 2−3 orders of magnitude higher than those of urban atmospheric PM_(2.5).According to structural equation model analysis,metal concentrations in<1μm fractions,PNCs of Fe-/Ti-containing NPs,and their corresponding dissolved Fe/Ti(including NPs with minute sizes)can regulate OP of<1μm fractions in CFAs.Elevated PNCs of MNPs in CFAs can be produced by CFPPs burning low-rank coals and with a low combustion efficiency boiler(e.g.,circulating fluidized-bed boiler).Once entering lung fluids,they likely release more dissolved metals or tiny corresponding NPs,thus generating greater OP.This study provides the first comprehensive investigation of OP generated by MNPs in CFAs. 展开更多
关键词 metal-containing NPs coal fly ash SP-ICP-MS oxidative potential simulated lung fluids
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Chemical characteristics,oxidative potential,and sources of PM_(2.5)in wintertime in Lahore and Peshawar,Pakistan 被引量:4
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作者 Mushtaq Ahmad Qing Yu +3 位作者 Jing Chen Siming Cheng Weihua Qin Yuepeng Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第4期148-158,共11页
The chemical characteristics,oxidative potential,and sources of PM_(2.5)were analyzed at the urban sites of Lahore and Peshawar,Pakistan in February 2019.Carbonaceous species,water soluble ions,and metal elements were... The chemical characteristics,oxidative potential,and sources of PM_(2.5)were analyzed at the urban sites of Lahore and Peshawar,Pakistan in February 2019.Carbonaceous species,water soluble ions,and metal elements were measured to investigate the chemical composition and sources of PM_(2.5).The dithiothreitol(DTT)consumption rate was measured to evaluate the oxidative potential of PM_(2.5).Both cities showed a high exposure risk of PM_(2.5)regarding its oxidative potential(DTT v).Carbonaceous and some of the elemental species of PM_(2.5)correlated well with DTT v in both Lahore and Peshawar.Besides,the DTT v of PM_(2.5)in Lahore showed significant positive correlation with most of the measured water soluble ions,however,ions were DTT-inactive in Peshawar.Due to the higher proportions of carbonaceous species and metal elements,Peshawar showed higher mass-normalized DTT activity of PM_(2.5)compared to Lahore although the average PM_(2.5)concentration in Peshawar was lower.The high concentrations of toxic metals also posed serious non-carcinogenic and carcinogenic risks to the residents of both cities.Principle component analysis coupled with multiple linear regression was applied to investigate different source contributions to PM_(2.5)and its oxidative potential.Mixed sources of traffic and road dust resuspension and coal combustion,direct vehicle emission,and biomass burning and formation of secondary aerosol were identified as the major sources of PM_(2.5)in both cities.The findings of this study provide important data for evaluation of the potential health risks of PM_(2.5)and for formulation of efficient control strategies in major cities of Pakistan. 展开更多
关键词 Air pollution DTT Health risk oxidative potential Source apportionment
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Comparison of light absorption and oxidative potential of biodiesel/diesel and chemicals/diesel blends soot particles 被引量:2
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作者 Yu Kuang Yi Guo +4 位作者 Jiaqi Chai Jing Shang Jiali Zhu Svetlana Stevanovic Zoran Ristovski 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第1期184-193,共10页
Soot particles,mainly coming from fuel combustion,affect climate forcing through absorbing light and also result in adverse human health outcomes.Though biodiesel or additives blending with diesel was considered envir... Soot particles,mainly coming from fuel combustion,affect climate forcing through absorbing light and also result in adverse human health outcomes.Though biodiesel or additives blending with diesel was considered environmentally friendly,the understanding on absorbing and oxidative capacity of soot emitted from them are still unclear.The watersoluble organic carbon(WSOC)content,surface chemical structure,light absorption and oxidative potential(OPDTT)of soot from biodiesel/diesel and chemicals/diesel blends were investigated utilizing total organic carbon analyzer,X-ray photoelectron spectrometer,ultraviolet–visible spectrophotometry and dithiothreitol(DTT)assay.The differences and correlations between soot properties were statistically analyzed.Chemicals/diesel blends soot owned significantly higher WSOC content,ratio of mass absorbing efficiency(MAE)in250 and 365 nm(E2/E3),OPDTT,and higher surface carbonyl content.Coconut biodiesel/diesel blends soot contained evidently higher aromatic carbon–oxygen single bond(ArC–O)content,and higher MAE365.The individual comparison of biodiesel/diesel blends showed20%coconut biodiesel blend owned the lowest WSOC,E2/E3 and OPDTT,while highest ArC–O and MAE365,representing strongest absorbing properties.Association analysis showed OPDTTwas significantly positively correlated with WSOC.Further,the evident negative correlation between MAE365 and OPDTT was observed.Our results showed coconut biodiesel/diesel blends soot induced lower levels of oxidative potential,whereas absorption of light was higher,which have far reaching consequences on climate forcing.Therefore,it is important to evaluate the balance point between light-absorbing properties and oxidative potential,under the wide use of biodiesel. 展开更多
关键词 Soot particle BIODIESEL Light absorption Mass absorbing efficiency oxidative potential Dithiothreitol(DTT)
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Heterogeneous oxidation of SO_2 by O_3-aged black carbon and its dithiothreitol oxidative potential 被引量:3
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作者 Weiwei Xu Qian Li +3 位作者 Jing Shang Jia Liu Xiang Feng Tong Zhu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第10期56-62,共7页
Ozone(O3) is an important atmospheric oxidant. Black carbon(BC) particles released into the atmosphere undergo an aging process via O3 oxidation. O3-aged BC particles may change their uptake ability toward trace r... Ozone(O3) is an important atmospheric oxidant. Black carbon(BC) particles released into the atmosphere undergo an aging process via O3 oxidation. O3-aged BC particles may change their uptake ability toward trace reducing gases such as SO2 in the atmosphere,leading to different environmental and health effects. In this paper, the heterogeneous reaction process between O3-aged BC and SO2 was explored via in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS). Combined with ion chromatography(IC),DRIFTS was used to qualitatively and quantitatively analyze the sulfate product. The results showed that O3-aged BC had stronger SO2 oxidation ability than fresh BC, and the reactive species/sites generated on the surface had an important role in the oxidation of SO2.Relative humidity or 254 nm UV(ultraviolet) light illumination enhanced the oxidation uptake of SO2 on O3-aged BC. The oxidation potentials of the BC particles were detected via dithiothreitol(DTT) assay. The DTT activity over BC was decreased in the process of SO2 reduction, with the consumption of oxidative active sites. 展开更多
关键词 Black carbon Ozone SO2 Heterogeneous reaction oxidative potential Dithiothreitol assay
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Multiscattering-enhanced absorbance to enable the sensitive analysis of extremely diluted biological samples: Determination of oxidative potential in exhaled air
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作者 Sami Goekce Nicolas Concha-Lozano +7 位作者 Jean-Jacques Sauvain Maud Hemmendinger Alejandro Portela Elise Sergent Pascal Andujar Jean-Claude Pairon Pascal Wild Guillaume Suarez 《Medicine in Novel Technology and Devices》 2022年第2期62-66,共5页
Direct determination of the oxidative potential in exhaled air(OPEA)as a biological indicator of the redox balance status in airways requires an extremely sensitive sensing approach to counterbalance the high dilution... Direct determination of the oxidative potential in exhaled air(OPEA)as a biological indicator of the redox balance status in airways requires an extremely sensitive sensing approach to counterbalance the high dilution of the exhaled air matrix.In opposite to standard colorimetric assays based on Beer-Lambert Law,the use of simple multiscattering-enhanced absorbance(MEA)strategy results in an improved photonic sensing system.Based on this strategy and using the ferrous-xylenol orange assay,analytical performances allowing the detection of 3 pmol of H_(2)O_(2) could be obtained.The comparative analysis of photometric configurations–standard vs MEA–highlights the large absorbance gain obtained for tiny H_(2)O_(2) amounts–from 0 to 30 pmol–whereas similar sensing trends are observed at higher concentration range.The automated introduction of exhaled air sample into the reaction compartment via needle-impinger coupled with the MEA-based photonic cell enables ultrasensitive determination of OPEA in short time(<5 min).A pilot study conducted on healthy subjects(n=22)and chronic obstructive pulmonary disease(COPD)patients(n=23)volunteers shows a significant increase of the OPEA for COPD versus controls and strong negative correlation between OPEA and spirometry parameters(Tiffeneau index:FEV1/FVC)for ex-/non-smokers.Application perspectives to assess inflammatory episodes in obstructive lung diseases are thus made possible using this sensing approach. 展开更多
关键词 Absorbance enhancement Photonic device oxidative potential Exhaled air COPD Pilot study
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Potential oxidative stress in children with chronic constipation 被引量:2
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作者 Jun-FuZhou Jian-GuoLou +1 位作者 Sheng-LiZhou Ji-YueWang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第3期368-371,共4页
AIM: To investigate the potential oxidative stress in children with -chronic constipation and to explore its mechanisms.METHODS: Seventy children with chronic constipation and 70 age- and sex-matched healthy children ... AIM: To investigate the potential oxidative stress in children with -chronic constipation and to explore its mechanisms.METHODS: Seventy children with chronic constipation and 70 age- and sex-matched healthy children were enrolled in a randomized controlled study. Plasma levels of vitamins C and E, activities of superoxide dismutase and catalase and lipoperoxide level in erythrocytes were determined by spectrophotometry.RESULTS: Compared with healthy children whose vitamin C,vitamin E, superoxide dismutase, catalase and lipoperoxide were 58.35±14.42 μmol/L, 27.15±6.55 μmol/L, 2 206±171U/(g· Hb), 327.3±82.2 K/(g·Hb) and 19.18±4.27 nmol/(g·Hb)respectively, the levels of vitamin C, vitamin E, the activity of superoxide dismutase, and catalase in the children with chronic constipation significantly decreased [46.59±11.51 μmol/L,20.65±4.80 μmol/L, 1943±147 U/(g·Hb) and 269.3±67.8 K/(g·Hb),respectively P<0.01], while the lipoperoxide significantly increased [25.22±5.01 nmol/(g·Hb), P<0.01]. With a prolonged course of disease, the levels of vitamin C, vitamin E, the activity of superoxide dismutase and catalase in the children with chronic constipation gradually decreased,while the level of lipoperoxide gradually increased.CONCLUSION: Chronic constipation can cause potential oxidative stress in children. 展开更多
关键词 Chronic constipation potential oxidative stress SPECTROPHOTOMETRY
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Further Investigation on the Correlation between Ionization Potential and Superconductivity of Oxides
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作者 Wei CHEM and Ruzhang MA(Dept. of Materials Physics, University of Science and Technology Bejing, Bejing, 100083, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1994年第6期455-458,共4页
The relations of oxygen content, critical temperature TC and mean ionization potential < U0> of superconducting oxides are reported. We found that in oxides oxygen is the major element which governs their < U... The relations of oxygen content, critical temperature TC and mean ionization potential < U0> of superconducting oxides are reported. We found that in oxides oxygen is the major element which governs their < U0> te values and thus oxygen content plays an jmportant role in their superconducting properties. As for Y(123)- and T1-systems oxygenation may improve their TC values, but for Biand Hg-systems oxygenation process is not so important. In Y(123), as the oxygen content increase results in the increase of TC upon < U0>to, while the substitution of Ba2+ by Sr2+ causes the decrease of TC upon < U0 >. These results may provide some clues about the superconductivity of oxides and support further that < Uo > is really a good criterion for oxide superconductivity. Two kinds of possible superconducting oxides are predicted in this paper according to the mean ionization potential criterion. 展开更多
关键词 CUO Nature Further Investigation on the Correlation between Ionization potential and Superconductivity of Oxides
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Concentration-dependent effects of reductive pulmonary inhalants on ultrafine particle-induced oxidative stress:Insights for health risk assessment
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作者 Ya-qi Yu Tong Zhu 《Environmental Science and Ecotechnology》 SCIE 2024年第3期118-124,共7页
The impact of reductive pulmonary inhalants on ultrafine particles(UFPs)-induced pulmonary oxidative stress remains a crucial consideration,yet the concentration-dependent effects of these inhalants have remained unex... The impact of reductive pulmonary inhalants on ultrafine particles(UFPs)-induced pulmonary oxidative stress remains a crucial consideration,yet the concentration-dependent effects of these inhalants have remained unexplored.Here we synthesized composite UFPs simulating atmospheric UFPs,primarily composed of metals and quinones.We subjected these UFPs to varying concentrations(0e7000 mM)of two reductive pulmonary inhalants,N-acetylcysteine and salbutamol,to assess their influence on oxidative potential,measured through the dithiothreitol assay(OP^(DTT)).Simultaneously,we analysed the soluble metal content of UFPs to uncover potential relationships between oxidative potential and metal solubility.Our results unveil a dual role played by these inhalants in shaping the OPDTT of composite UFPs.Specifically,OP^(DTT) generally increased as inhalant concentrations rose from 0 to 300 mM.However,an intriguing reversal occurred when concentrations exceeded 500 mM,resulting in a decline in OPDTT.Relative to untreated UFPs,these inhalants induced promotion and inhibition effects within concentration ranges of 100e500 and>1000 mM,respectively.While no significant correlation emerged between OP^(DTT) and soluble metal content as inhalant concentrations ranged from 0 to 7000 mM,noteworthy positive correlations emerged at lower inhalant concentrations(e.g.,N-acetylcysteine at 0 e300 mM).These findings provide insights into the potential influence of reductive pulmonary inhalants on health risks associated with UFP exposure,further underscoring the need for continued research in this critical area. 展开更多
关键词 Concentration-dependent effects oxidative potential Reductive pulmonary inhalants Soluble metals Simulated atmospheric ultrafine particles
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Indoor Simulation Study on Nutrient Release of Fishponds Sediment 被引量:2
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作者 杜旭彤 谢骏 +2 位作者 王广军 余德光 赵旭斌 《Agricultural Science & Technology》 CAS 2009年第3期127-130,138,共5页
[Objective] The study aimed to research the nutrients release of ponds sediment.[Method] The sediments which from a new pond(A) and an old one (B) these analyses used to carry out indoor experiment under the anaerobic... [Objective] The study aimed to research the nutrients release of ponds sediment.[Method] The sediments which from a new pond(A) and an old one (B) these analyses used to carry out indoor experiment under the anaerobic dark condition for researching on nutrient release. The N(nitrogenous) and P(phosphorous) release were analyzed every two days.[Result] At the prophase, the N release in B was bigger than that in A, while the decline sediment release in A was gentle.[Conclusion] There was no accumulation of organic compound during the breeding time. The NH4-N was the main form of N release; and the P release was correlated with N release, while PO4-P was the main form of P release. 展开更多
关键词 SEDIMENT Nutrient release Indoor simulation study Oxidation reduction potential (ORP)
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The effects of nitrogen fertilizer application on methane and nitrous oxide emission/uptake in Chinese croplands 被引量:18
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作者 SUN Bin-feng ZHAO Hong +2 位作者 LU Yi-zhong Lü Fei WANG Xiao-ke 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第2期440-450,共11页
The application of nitrogen(N) fertilizer to increase crop yields has a significant influence on soil methane(CH_4) and nitrous oxide(N_2O) emission/uptake.A meta-analysis was carried out on the effect of N appl... The application of nitrogen(N) fertilizer to increase crop yields has a significant influence on soil methane(CH_4) and nitrous oxide(N_2O) emission/uptake.A meta-analysis was carried out on the effect of N application on(i) CH_4 emissions in rice paddies,(ii) CH_4 uptake in upland fields and(iii) N_2O emissions.The responses of CH_4 emissions to N application in rice paddies were highly variable and overall no effects were found.CH_4 emissions were stimulated at low N application rates(〈100 kg N ha^(-1)) but inhibited at high N rates(〉200 kg N ha^(-1)) as compared to no N fertilizer(control).The response of CH_4 uptake to N application in upland fields was 15%lower than control,with a mean CH_4 uptake factor of-0.001 kg CH_4-C kg^(-1) N.The mean N_2O emission factors were 1.00 and 0.94%for maize(Zea mays) and wheat(Triticum aestivum),respectively,but significantly lower for the rice(Oryza sativa)(0.51%).Compared with controls,N addition overall increased global warming potential of CH_4 and N_2O emissions by 78%.Our result revealed that response of CH_4 emission to N input might depend on the CH_4concentration in rice paddy.The critical factors that affected CH_4 uptake and N_2O emission were N fertilizer application rate and the controls of CH_4 uptake and N_2O emission.The influences of application times,cropping systems and measurement frequency should all be considered when assessing CH_4 and N_2O emissions/uptake induced by N fertilizer. 展开更多
关键词 nitrogen fertilizer methane nitrous oxide global warming potential emission factor
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Phase Analysis of Titanium in Steel and Some Aspects on Their Application 被引量:1
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作者 CHEN Ming Hao and SHEN Ru Mei 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 1994年第1期51-55,共5页
Phase analysis of titanium in steel has been carried out on thirty samples with different Ticontent from 0. 036 %-0. 204% . The various heat treatments for the samples are to anneal at 1050-1200 ℃ for a while ,follo... Phase analysis of titanium in steel has been carried out on thirty samples with different Ticontent from 0. 036 %-0. 204% . The various heat treatments for the samples are to anneal at 1050-1200 ℃ for a while ,followed by cooling at a rate of 1 . 10, 20 ℃/s ,respectively.It is achieved to separate and determine fine particle TiC ,coarse particle Ti_2CS and TiN ex-tracted from steel by controlling the oxidation potential and acidity of solutions.The results of quantrtative analysis of the individual phase show that 0. 09 %- 0. 13 % Ti-contentis enough to eliminate free nitrogen and transform MnS into Yi_2CS in steel effectively. In the case of0. 06 %- 0. 10 % Ti-content combined with annealing at 1050℃. and quick cooling at 20 ℃/s ,a prop-er amount of fine particle TiC can be precipitated and the rate of TiC (fine )/TiC (total )is high ,which arebeneficial to increase strength and toughness of steel. More Ti-content or cooling slowly will preciprtatemore coarse particle TiC which decreaces toughness severely. The proposed methods for quantitativephase analysis of titanium in steel are given in detail. 展开更多
关键词 hase analysis oxidation potential.precipitation strengthening
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THE EFFECTS OF SHORT CHAIN FATTY ACID ON BIOLOGICAL PHOSPHATE RELEASE AND PHB SYNTHESIS UNDER ANAEROBIC CONDITION 被引量:1
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作者 田淑媛 《Transactions of Tianjin University》 EI CAS 1996年第2期93+89-92,共5页
The basic objective of this research is to determine the effects of acetate, propionate and butyrate on the biological phosphate(bio p) release and poly β hydroxybutyrate(PHB) synthesis and... The basic objective of this research is to determine the effects of acetate, propionate and butyrate on the biological phosphate(bio p) release and poly β hydroxybutyrate(PHB) synthesis and to test the effects of different acetate concentrations on the bio p release as well as the effect of butyrate on the bio p release and PHB synthesis in the presence of nitrates. Oxidation reduction potential probes are used to monitor the relative anaerobic and anoxic states of the sewage. The author quantified PHB, PHV in activated sludge by gas liquid chromatography. It has been demonstrated through a series of batch experiments that phosphorus release and PHB synthesis both take place in anaerobic zone of the bio p removal process, and the key factors to the maximization of PHB synthesis are that simple carbon substrates should be added to the anaerobic zone and that the addition of electron acceptors should be avoided. 展开更多
关键词 biological excess phosphate removal(BEPR) poly β hydroxybutyrate(PHB) oxidation reduction potential(ORP)
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Response of soil microbial activities and ammonia oxidation potential to environmental factors in a typical antimony mining area 被引量:1
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作者 Aihua Wang Shujun Liu +4 位作者 Jun Xie Wei Ouyang Mengchang He Chunye Lin Xitao Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第5期767-779,共13页
Mining,smelting and tailing deposition activities can cause metal(loid)contamination in surrounding soils,threatening ecosystems and human health.Microbial indicators are sensitive to environmental factors and have a ... Mining,smelting and tailing deposition activities can cause metal(loid)contamination in surrounding soils,threatening ecosystems and human health.Microbial indicators are sensitive to environmental factors and have a crucial role in soil ecological risk assessment.Xikuangshan,the largest active antimony(Sb)mine in the world,was taken as the research area.The soil properties,metal(loid)contents and microbial characteristics were investigated and their internal response relationships were explored by multivariate statistical analysis.The assessment of the single pollution index and Nemerow synthetic pollution index(PN)showed that the soils were mainly polluted by Sb,followed by Cd and As,in which sampling site S1 had a slight metal(loid)pollution and the other sampling sites suffered from severe synthetic metal(loid)pollution.The microbial characteristics were dissimilar among sampling points at different locations from the mining area according to hierarchical cluster analysis.The correlation analysis indicated that fluorescein diacetate hydrolase,acid phosphatase,soil basal respiration andmicrobial biomass carbonwere negatively correlatedwith PN,indicating their sensitivity to combined metal(loid)contamination;that dehydrogenase was positively correlated with pH;and that urease,potential ammonia oxidation and abundance of ammonia-oxidizing bacteria and archaea were correlated with N(nitrogen)contents.However,β-glucosidase activity had no significant correlations with physicochemical properties and metal(loid)contents.Principal components analysis suggested bioavailable Sb and pH were the dominant factors of soil environment in Xikuangshan Sb mining area.Our results can provide a theoretical basis for ecological risk assessment of contaminated soil. 展开更多
关键词 Antimony mining area Metal(loid)pollution Microbial characteristics Enzyme activities Ammonia oxidation potential
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Influences on oxidation voltage and holding time on poly(3-methylthiophene) film for electrochromic stability
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作者 Bo Zhang Chen Xu +3 位作者 Guo-Yue Xu Chu-Yang Liu Hong-Han Bu Jian-Chao Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第12期493-498,共6页
In this study, we report the influences of oxidation potential and holding time on the electrochromic(EC) stability of poly(3-methylthiophene)(P3MT) film during the electrochemical reaction. The cycle stability and tr... In this study, we report the influences of oxidation potential and holding time on the electrochromic(EC) stability of poly(3-methylthiophene)(P3MT) film during the electrochemical reaction. The cycle stability and transmittance changes of the film were investigated by optimizing the oxidation potential, and its chemical compositions were measured by x-ray photoelectron spectra after multiple electrochemical cycles. High oxidation potentials can increase the P3MT film color contrast and decrease its cycle stability because of accelerating chemical decomposition. Moreover, the holding time with potential pulsing was analyzed by using the optical memory of P3MT at an optimized oxidation potential, which revealed the reduced voltage duration saved energy consumption by 11.6% and improved the EC cycle stability without changing in color contrast. 展开更多
关键词 ELECTROCHROMISM P3MT oxidation potential cycle stability
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Responses of potential ammonia oxidation and ammonia oxidizers community to arsenic stress in seven types of soil
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作者 Yanan Wang Xibai Zeng +3 位作者 Yang Zhang Nan Zhang Liyang Xu Cuixia Wu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第5期15-29,共15页
Soil arsenic contamination is of great concern because of its toxicity to human,crops,and soil microorganisms.However,the impacts of arsenic on soil ammonia oxidizers communities remain unclear.Seven types of soil spi... Soil arsenic contamination is of great concern because of its toxicity to human,crops,and soil microorganisms.However,the impacts of arsenic on soil ammonia oxidizers communities remain unclear.Seven types of soil spiked with 0 or 100 mg arsenic per kg soil were incubated for 180 days and sampled at days 1,15,30,90 and 180.The changes in the community composition and abundance of ammonia oxidizing bacteria(AOB)and ammonia oxidizing archaea(AOA)were analyzed by terminal restriction fragment length polymorphism(TRFLP)analysis,clone library sequencing,and quantitative PCR(qPCR)targeting amoA gene.Results revealed considerable variations in the potential ammonia oxidation(PAO)rates in different soils,but soil PAO was not consistently significantly inhibited by arsenic,probably due to the low bioavailable arsenic contents or the existence of functional redundancy between AOB and AOA.The variations in AOB and AOA communities were closely associated with the changes in arsenic fractionations.The amoA gene abundances of AOA increased after arsenic addition,whereas AOB decreased,which corroborated the notion that AOA and AOB might occupy different niches in arsenic-contaminated soils.Phylogenetic analysis of amoA gene-encoded proteins revealed that all AOB clone sequences belonged to the genus Nitrosospira,among which those belonging to Nitrosospira cluster 3a were dominant.The main AOA sequence detected belonged to Thaumarchaeal Group 1.1b,which was considered to have a high ability to adapt to environmental changes.Our results provide new insights into the impacts of arsenic on the soil nitrogen cycling. 展开更多
关键词 Ammonia oxidizers Arsenic potential ammonia oxidation(PAO) rate Ecological niche Terminal restriction fragment length polymorphism(T-RFLP) analysis
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Ambient particle composition and toxicity in 31 major cities in China 被引量:1
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作者 Lu Zhang Maosheng Yao 《Fundamental Research》 CAS CSCD 2024年第3期505-515,共11页
Current assessment of air quality or control effectiveness is solely based on particulate matter(PM)mass levels,without considering their toxicity differences in terms of health benefits.Here,we collected a total of 4... Current assessment of air quality or control effectiveness is solely based on particulate matter(PM)mass levels,without considering their toxicity differences in terms of health benefits.Here,we collected a total of 465 automo-bile air conditioning filters from 31 major Chinese cities to study the composition and toxicity of PM at a national scale.Dithiothreitol assay showed that normalized PM toxicity(NIOG)in different Chinese cities varied greatly from the highest 4.99×10^(-3)for Changsha to the lowest 7.72×10^(-4)for Yinchuan.NI0G values were observed to have significant correlations with annual PM_(10) concentration(r=-0.416,p=0.020)and some PM components(total fungi,so.2-and calcium element).The concentrations of different elements and water-soluble ions in PM also varied by several orders of magnitude for 31 cities in China.Endotoxin concentrations in PM analyzed using limulus amebocyte lysate assay ranged from 2.88 EU/mg PM(Hangzhou)to 62.82 EU/mg PM(Shijiazhuang)among 31 Chinese cities.Besides,real-time qPCR revealed 10~100-fold differences in total bacterial and fungal levels among 31 Chinese cities.The concentrations of chemical(water soluble ions and trace elements)and bi-ological(fungi,bacteria and endotoxin)components in PM were found to be significantly correlated with some meteorological factors and gaseous pollutants such as SO_(2).Our results have demonstrated that PM toxicity from 31 major cities varied greatly up to 6.5 times difference;and components such as fungi and SO_(4)^(2-)in PM could play important roles in the observed PM toxicity.The city-specific air pollution control strategy that integrates toxicity factors should be enacted in order to maximize health and economic co-benefits.This work also provides a comprehensive view on the overall PM pollution situation in China. 展开更多
关键词 PM toxicity oxidative potential BIOLOGICALS Chemical components ENDOTOXIN
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Comparison of different valent iron on anaerobic sludge digestion:Focusing on oxidation reduction potential,dissolved organic nitrogen and microbial community 被引量:1
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作者 Zecong Yu Keke Xiao +6 位作者 Yuwei Zhu Mei Sun Sha Liang Jingping Hu Huijie Hou Bingchuan Liu Jiakuan Yang 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2022年第6期159-170,共12页
This study compared effects of three different valent iron(Fe^(0),Fe(II)and Fe(III))on enhanced anaerobic sludge digestion,focusing on the changes of oxidation reduction potential(ORP),dissolved organic nitrogen(DON),... This study compared effects of three different valent iron(Fe^(0),Fe(II)and Fe(III))on enhanced anaerobic sludge digestion,focusing on the changes of oxidation reduction potential(ORP),dissolved organic nitrogen(DON),and microbial community.Under the same iron dose in range of 0−160 mg/L after an incubation period of 30 days(d),the maximum methane production rate of sludge samples dosed with respective Fe^(0),Fe(II)and Fe(III)at the same concentration showed indiscernible differences at each iron dose,regardless of the different iron valence.Moreover,their behavior in changes of ORP,DON and microbial community was different:(1)the addition of Fe^(0) made the ORP of sludge more negative,and the addition of Fe(II)and Fe(III)made the ORP of sludge less negative.However,whether being more or less negative,the changes of ORP may show unobservable effects on methane yield when it ranged from−278.71 to−379.80 mV;(2)the degradation of dissolved organic nitrogen,particularly proteins,was less efficient in sludge samples dosed with Fe^(0) compared with those dosed with Fe(II)and Fe(III)after an incubation period of 30 d.At the same dose of 160 mg/L iron,more cysteine was noted in sludge samples dosed with Fe(II)(30.74 mg/L)and Fe(III)(27.92 mg/L)compared with that dosed with Fe^(0)(21.75 mg/L);(3)Fe^(0) particularly promoted the enrichment of Geobacter,and it was 6 times higher than those in sludge samples dosed with Fe(II)and Fe(III)at the same dose of 160 mg/L iron. 展开更多
关键词 Enhanced anaerobic sludge digestion Different iron valence Oxidation reduction potential Dissolved organic nitrogen Microbial community
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Structural and Mechanistic Aspects of Mn-oxo and Co-based Compounds in Water Oxidation Catalysis and Potential Applications in Solar Fuel Production 被引量:1
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作者 Harvey J.M.Hou 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2010年第8期704-711,共8页
To address the issues of energy crisis and global warming, novel renewable carbon-free or carbon-neutral energy sources must be identified and developed. A deeper understanding of photosynthesis is the key to provide ... To address the issues of energy crisis and global warming, novel renewable carbon-free or carbon-neutral energy sources must be identified and developed. A deeper understanding of photosynthesis is the key to provide a solid foundation to facilitate this transformation. To mimic the water oxidation of photosystem II oxygen evolving complex, Mn-oxo complexes and Co-phosphate catalytic material were discovered in solar energy storage. Building on these discoveries, recent advances in solar energy conversion showed a compelling working principle by combing the active Mn-oxo and Co-based catalysts in water splitting with semiconductor heteronanostructures for effective solar energy harnessing. In this review the appealing systems including Mn-oxo tetramer/Nafion, Mn-oxo dimer/TiO2, Mn-oxo oligomer/WO3, Co-Pi/Fe2O3, and Co-Pi/ZnO are summarized and discussed. These accomplishments offer a promising framework and have a profound impact in the field of solar fuel production. 展开更多
关键词 Mn Structural and Mechanistic Aspects of Mn-oxo and Co-based Compounds in Water Oxidation Catalysis and potential Applications in Solar Fuel Production II Figure
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Estimation of the Postmortem Interval by Measuring Blood Oxidation‑reduction Potential Values
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作者 Zhuqing Jiang Meng You +10 位作者 Xu Wang Di Lu Haidong Zhang Shengli Di Fengqin Zhang Zhaoming Guo Xiaofei E Lin Chang Jian Xiang Rufeng Bai Tiantong Yang 《Journal of Forensic Science and Medicine》 2016年第1期8-11,共4页
Accurate estimation of the postmortem interval(PMI)is an important task in forensic practice.In the last half-century,the use of postmortem biochemistry has become an important ancillary method in determining the time... Accurate estimation of the postmortem interval(PMI)is an important task in forensic practice.In the last half-century,the use of postmortem biochemistry has become an important ancillary method in determining the time of death.The present study was carried out to determine the correlation between blood oxidation-reduction potential(ORP)values and PMIs,and to develop a three-dimensional surface equation to estimate the PMI under various temperature conditions.A total of 48 rabbits were placed into six groups and sacrificed by air embolism.Blood was obtained from the right ventricle of each rabbit,and specimens were stored at 10℃,15℃,20℃,25℃,30℃,and 35℃.At different PMIs(once every 4 h),the blood ORP values were measured using a PB-21 electrochemical analyzer.Statistical analysis and curve fitting of the data yielded cubic polynomial regression equations and a surface equation at different temperatures.Result:The results showed that there was a strong positive correlation between the blood ORP values at different temperatures and the PMI.This study provides another example of using a three-dimensional surface equation as a tool to estimate the PMI at various temperature conditions. 展开更多
关键词 Forensic science interpolation function oxidation‑reduction potential postmortem interval three‑dimensional surface equation
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Aqueous Chemistry of Typical Geothermal Springs with Deep Faults in Xinyi and Fengshun in Guangdong Province,China 被引量:10
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作者 Guoping Lu Runfang Liu 《Journal of Earth Science》 SCIE CAS CSCD 2015年第1期60-72,共13页
This paper investigated aqueous chemistry for two geothermal spring groups responsive and sensitive to flow fluctuations induced by earthquakes. Quake monitorings are favored for their being in residential areas with ... This paper investigated aqueous chemistry for two geothermal spring groups responsive and sensitive to flow fluctuations induced by earthquakes. Quake monitorings are favored for their being in residential areas with well-preserved natural flow systems in Xinyi City's Xijiang Hot Springs and Fengshun County's Shihu Hot Spring. The hot springs are typical in temperatures and flow rates in southern China's Guangdong Province. Physical and chemical conditions deep down in the heat sources are important constraints on earthquake, fluid flow, reactive solute transport and heat transfer, but remain challenging to address via field observations and numerical experiments. In this paper, we made daily and annual observations on flow rates, temperature, and/or aqueous chemistry. We employed strontium isotopes as tracers for the water sources, equilibrium phase diagram for K-feldspar and albite stability, and Na-K-Mg diagram for heat reservoir temperatures. The abundant sulfite content in Xi- jiang Hot Springs is discussed. Our main finding are that the deep fault springs are characterized by low reduction-oxidation potential at around -200- -150 mV and relatively large daily flow variations. The resuits provide scientific background features on the field sites regarding earthquake monitoring and predictions and geothermal reservoir. 展开更多
关键词 GEOTHERMAL hot spring aqueous geochemistry earthquake monitoring geothermal reservoir temperature reduction oxidation potential Xinyi Fengshun.
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