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Tetrathiafulvalene esters with high redox potentials and improved solubilities for non-aqueous redox flow battery applications
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作者 Weikang Hu Jiaqi Xu +3 位作者 Nanjie Chen Zongcai Deng Yuekun Lai Dongyang Chen 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期899-908,共10页
The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxflow batteries.Herein,three tetrathiofulvalene(TTF)derivatives with different substitution gr... The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxflow batteries.Herein,three tetrathiofulvalene(TTF)derivatives with different substitution groups,namely TTF diethyl ester(TTFDE),TTF tetramethyl ester(TTFTM),and TTF tetraethyl ester(TTFTE),are prepared and their energy storage properties are evaluated.It has been found that the redox potential and solubility of these TTF derivatives in conventional carbonate electrolytes increases with the number of ester groups.The battery with a catholyte of 0.2 mol L^(-1) of TTFTE delivers a specific capacity of more than 10 Ah L^(-1) at the current density of 0.5 C with two discharge voltage platforms locating at as high as 3.85 and 3.60 V vs.Li/Liþ.Its capacity retention can be improved from 2.34 Ah L^(-1) to 3.60 Ah L^(-1) after 100 cycles by the use of an anion exchange membrane to block the crossover of TTF species.The excellent cycling stability of the TIF esters is supported by their well-delocalized electrons,as revealed by the density function theory calculations.Therefore,the introduction of more and larger electron-withdrawing groups is a promising strategy to simultaneously increase the redox-potential and solubility of redox-active ma-terials for non-aqueous redoxflow batteries. 展开更多
关键词 Non-aqueous redox flow batteries Tetrathiofulvarene redox potential SOLUBILITY Substituent effect
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Relationship and effect of redox potential,jarosites and extracellular polymeric substances in bioleaching chalcopyrite by acidithiobacillus ferrooxidans 被引量:13
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作者 余润兰 钟代立 +3 位作者 苗雷 吴发登 邱冠周 顾国华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第7期1634-1640,共7页
The changes of pH,redox potential,concentrations of soluble iron ions and Cu^2+ with the time of bioleaching chalcopyrite concentrates by acidithiobacillus ferrooxidans were investigated under the different condition... The changes of pH,redox potential,concentrations of soluble iron ions and Cu^2+ with the time of bioleaching chalcopyrite concentrates by acidithiobacillus ferrooxidans were investigated under the different conditions of initial total-iron amount as well as mole ratio of Fe(III) to Fe(II) in the solutions containing synthetic extracellular polymeric substances (EPS).When the solution potential is lower than 650 mV (vs SHE),the inhibition of jarosites to bioleaching chalcopyrite is not vital as EPS produced by bacteria can retard the contamination through flocculating jarosites even if concentration of Fe(III) ions is up to 20 g/L but increases with increasing the concentration of Fe(III) ions;jarosites formed by bio-oxidized Fe3+ ions are more easy to adhere to outside surface of EPS space on chalcopyrite;the EPS layer with jarosites acts as a weak diffusion barrier to further rapidly create a high redox potential of more than 650 mV by bio-oxidizing Fe^2+ ions inside and outside EPS space into Fe^3+ ions,resulting in a rapid deterioration of ion diffusion performance of the EPS layer to inhibit bioleaching chalcopyrite severely and irreversibly. 展开更多
关键词 extracellular polymeric substances CHALCOPYRITE BIOLEACHING jarosites redox potential
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Phosphorus in Interstitial Water Induced by Redox Potential in Sediment of Dianchi Lake,China 被引量:34
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作者 LI Qing-Man ZHANG Wen +3 位作者 WANG Xing-Xiang ZHOU Yi-Yong YANG Hao JI Guo-Liang 《Pedosphere》 SCIE CAS CSCD 2007年第6期739-746,共8页
The sediment redox potential was raised in the laboratory to estimate reduction of internal available phosphorus loads,such as soluble reactive phosphorus(SRP)and total phosphorus(TP),as well as the main elements of s... The sediment redox potential was raised in the laboratory to estimate reduction of internal available phosphorus loads,such as soluble reactive phosphorus(SRP)and total phosphorus(TP),as well as the main elements of sediment extracts in Dianchi Lake.Several strongly reducing substances in sediments,which mainly originated from anaerobic decomposition of primary producer residues,were responsible for the lower redox potential.In a range of -400 to 200 mV raising the redox potential of sediments decreased TP and SRP in interstitial water.Redox potentials exceeding 320 mV caused increases in TP,whereas SRP maintained a relatively constant minimum level.The concentrations of Al,Fe, Ca^(2+),Mg^(2+),K^+,Na^+ and S in interstitial water were also related to the redox potential of sediments,suggesting that the mechanism for redox potential to regulate the concentration of phosphorus in interstitial water was complex. 展开更多
关键词 Dianchi Lake interstitial water PHOSPHORUS redox potential SEDIMENT
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Control of fermentation types in continuous-flow acidogenic reactors:effects of pH and redox potential 被引量:13
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作者 任南琪 陈小蕾 赵丹 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第2期116-119,共4页
The experiments were carried out in continuous flow acidogenic reactors with molasses used as substrate to study the effects of pH and redox potential on fermentation types. The conditions for each fermentation type w... The experiments were carried out in continuous flow acidogenic reactors with molasses used as substrate to study the effects of pH and redox potential on fermentation types. The conditions for each fermentation type were investigated at different experimental stages of start up, pH regulating and redox potential regulating. The experiments confirmed that butyric acid type fermentation would occur at pH > 6, the propionic acid type fermentation at pH about 5.5 with E h> -278 mV, and the ethanol type fermentation at pH < 4.5. A higher redox potential will lead to propionic acid type fermentation because propionogens are facultative anaerobic bacteria. 展开更多
关键词 wastewater anaerobic treatment acidogenic reactor fermentation types redox potential(OR)
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Redox potential E_H [Se(VI)/Se(IV)] of aqueous extractof soils from Yongshou Kaschin-Beck diseaseregion and the influence by humic acid
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作者 Peng An and Xu Langqiu Research Center for Eco-Environmental Sciences,Academia Sinica,Beijing 100083,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1989年第2期29-36,共8页
The relation between EH [Se(VI)/Se(IV)] and pH of soil aqueous extract in Kaschin-Beck disease region and the effects of natural redox agents, namely humic substances, MnO2 and Fe2+, on the redox property of the syste... The relation between EH [Se(VI)/Se(IV)] and pH of soil aqueous extract in Kaschin-Beck disease region and the effects of natural redox agents, namely humic substances, MnO2 and Fe2+, on the redox property of the system were studied. The results indicated that both humic acid and Fe2+ could enhance the reducibility of Se(VI) and MnO2, a limited oxidizability for Se(IV). Fe2+ showed a weak reducibility only at low pH value. The reducibilities of three sulfur-containing compounds for Se(VI) were in following order:thioglycollic acid > L-cysteine > sulfide 展开更多
关键词 SELENIUM redox potential Kaschin-Beck disease humic acid.
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Groundwater Level Effect on Redox Potential, on Cadmium Uptake and Yield of Soybean
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作者 Md. Zahidul Haque Choichi Sasaki +2 位作者 Nobuhiko Matsuyama Takeyuki Annaka Chihiro Kato 《American Journal of Plant Sciences》 2014年第20期3022-3031,共10页
In this greenhouse experiment, we investigated the effects of two constant groundwater levels: 10 cm groundwater level (GW-10) and 40 cm groundwater level (GW-40) and one change groundwater level, which was 40-10-40 c... In this greenhouse experiment, we investigated the effects of two constant groundwater levels: 10 cm groundwater level (GW-10) and 40 cm groundwater level (GW-40) and one change groundwater level, which was 40-10-40 cm (GW-40-10-40) on Cadmium (Cd) uptake and seed yield of Soybean plant in Cd contaminated soils (1.57 mg·kg-1). The experimental soil layer was made with gravel layer (14 cm), non-polluted soil (15 cm) and polluted soil (25 cm). The redox potential of every soil layer was measured from sowing to harvesting. The soil layer (10 – 40 cm) of GW-10 was always in reduction condition and that of GW-40 was always in oxidation condition. First 50 days of GW 40-10-40 were in oxidation and next 50 days in reduction and final 20 days again returned in oxidation condition. Soybean seed Cd concentration was significantly highest in GW-40-10-40 (1.16 ± 0.13 mg·kg-1) and lowest in GW-40 (0.81 ± 0.12 mg·kg-1). Cd concentration of stem was found significantly higher in GW-40 (1.7 ± 0.2 mg·kg-1) than GW-10 (0.91 ± 0.08 mg·kg-1) and GW-40-10-40 (1.28 ± 0.13 mg·kg-1). There was no significant difference in root Cd concentration among these 3 treatments. Main stem height of soybean plant and 100 seed weight of GW-40 were significantly higher than those of GW-10. The result revealed that, soil redox condition is an important factor for Cd uptake in soybean plant and seed yield of soybean. This study will help to manage the farming process more appropriately with the aim of minimizing uptake of Cd and other toxic metals in grain crops. 展开更多
关键词 Groundwater Level redox potential (eh) CADMIUM UPTAKE SOYBEAN SEED YIELD
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Dual-parameter Correlation Analysis of the Redox Potential Data of 1-Methyl-2-formyl-5-substituted Pyrroles and their Hydrazones
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作者 Hai Ying HE Chen Lin +1 位作者 Cheng Xue ZHAO Xi Kui JIANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第12期1097-1100,共4页
By using 1-methyl-2-formyl-5-substituted pyrroles (1-Y), 1-methyl-2-formyl-5-substituted pyrrole phenylhydrazones (2-Y) and 1-methyl-2-formyl-5-substituted pyrrole (4-nitrophenyl)-hydrazones (3-Y) as model structures ... By using 1-methyl-2-formyl-5-substituted pyrroles (1-Y), 1-methyl-2-formyl-5-substituted pyrrole phenylhydrazones (2-Y) and 1-methyl-2-formyl-5-substituted pyrrole (4-nitrophenyl)-hydrazones (3-Y) as model structures for nitrogen-containing heterocyclic aromatic compounds, correlation analysis of their redox potential data show that the transition states (TS) of the polarographic process are mainly affected by the polar effects, but spin-delocalizatin effects also exist. 展开更多
关键词 correlation analysis polar effect spin-delocalization effect redox potential
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Quantitative Analysis of the Relationship between Ruminal Redox Potential and pH in Dairy Cattle: Influence of Dietary Characteristics
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作者 Yayu Huang Jean Philippe Marden +3 位作者 Chaouki Benchaar Christine Julien Eric Auclair Corine Bayourthe 《Agricultural Sciences》 2017年第7期616-630,共15页
The ruminal redox potential (Eh) can reflect the microbiological activity and dynamics of fermentation in the rumen. It might be an important indicator of rumen fermentation in combination with pH. However, the rumina... The ruminal redox potential (Eh) can reflect the microbiological activity and dynamics of fermentation in the rumen. It might be an important indicator of rumen fermentation in combination with pH. However, the ruminal Eh has been rarely studied in dairy cows due to the difficulty of its measurement, and the relationship between ruminal Eh and pH is not clear. The objective of this study was to investigate the relationship between ruminal Eh and pH of dairy cows by meta-analysis of systematic measurements from different experiments. A database was constructed from 22 experiments on cannulated dairy cattle including 57 dietary treatments. The ruminal pH and Eh were measured without air contact between 0 and 8 h post-feeding. The results demonstrated a quadratic correlation between ruminal Eh and pH with a reliable within-animal variation (Eh = -1697 + 540.7 pH -47.7 pH2, nobservation = 70, nanimal = 26, P Eh, but not always to the same extent. Some of them still influenced the relationship between ruminal Eh and pH. While the mechanism of the interaction between ruminal Eh and pH remains to be elucidated, it would be interesting to associate Eh to microbial profile, ruminal VFA concentration and milk production performance in future studies. 展开更多
关键词 redox potential PH RUMEN Diet DAIRY COW
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Perspectives on aqueous organic redox flow batteries
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作者 Fulong Zhu Qiliang Chen Yongzhu Fu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第11期1641-1649,共9页
Aqueous organic redoxflow batteries(AORFBs)have pioneered new routes for large-scale energy storage.The tunable nature of redox-active organic molecules provides a robust foundation for creating innovative AORFBs with ... Aqueous organic redoxflow batteries(AORFBs)have pioneered new routes for large-scale energy storage.The tunable nature of redox-active organic molecules provides a robust foundation for creating innovative AORFBs with exceptional performance.Molecular engineering endows various organic molecules with considerable advantages in solubility,stability,and redox potential.Advanced characterizations have enabled a comprehensive understanding of the redox reaction and degradation mechanisms of these organic molecules.Computational chemistry and machine learning have guided the development of new organic molecules.The practical application of AORFBs will depend on the complementary efforts of multiple parties.This paper consolidates the current design principles of molecular engineering,degradation mechanisms,characterization techniques,and the utilization of computational chemistry.It also offers perspectives and forecasts the necessary attributes and strategic efforts for the next-generation AORFBs,aiming to provide the research community with a deeper understanding. 展开更多
关键词 potential redox exceptional
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Analysis of the electron transfer pathway in small laccase by EPR and UV-vis spectroscopy coupled with redox titration
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作者 Lu Yu Aokun Liu +3 位作者 Jian Kuang Ruotong Wei Zhiwen Wang Changlin Tian 《Magnetic Resonance Letters》 2024年第3期52-59,共8页
Bacterial small laccases(SLAC) are promising industrial biocatalysts due to their ability to oxidize a broad range of substrates with exceptional thermostability and tolerance for alkaline p H. Electron transfer betwe... Bacterial small laccases(SLAC) are promising industrial biocatalysts due to their ability to oxidize a broad range of substrates with exceptional thermostability and tolerance for alkaline p H. Electron transfer between substrate, copper centers, and O2is one of the key steps in the catalytic turnover of SLAC. However, limited research has been conducted on the electron transfer pathway of SLAC and SLAC-catalyzed reactions, hindering further engineering of SLAC to produce tunable biocatalysts for novel applications. Herein, the combinational use of electron paramagnetic resonance(EPR) and ultraviolet-visible(UV-vis) spectroscopic methods coupled with redox titration were employed to monitor the electron transfer processes and obtain further insights into the electron transfer pathway in SLAC. The reduction potentials for type 1 copper(T1Cu), type 2 copper(T2Cu) and type 3copper(T3Cu) were determined to be 367 ± 2 mV, 378 ± 5 m V and 403 ± 2 mV,respectively. Moreover, the reduction potential of a selected substrate of SLAC, hydroquinone(HQ), was determined to be 288 mV using cyclic voltammetry(CV). In this way, an electron transfer pathway was identified based on the reduction potentials. Specifically,electrons are transferred from HQ to T1Cu, then to T2Cu and T3Cu, and finally to O2.Furthermore, superhyperfine splitting observed via EPR during redox titration indicated a modification in the covalency of T2Cu upon electron uptake, suggesting a conformational alteration in the protein environment surrounding the copper sites, which could potentially influence the reduction potential of the copper sites during catalytic processes. The results presented here not only provide a comprehensive method for analyzing the electron transfer pathway in metalloenzymes through reduction potential measurements, but also offer valuable insights for further engineering and directed evolution studies of SLAC in the aim for biotechnological and industrial applications. 展开更多
关键词 Electron paramagnetic resonance redox titration Electron transfer Reduction potential Small laccase
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湿地林土壤的Fe^(2+),Eh及pH值的变化 被引量:71
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作者 唐罗忠 生原喜久雄 +1 位作者 户田浩人 黄宝龙 《生态学报》 CAS CSCD 北大核心 2005年第1期103-107,共5页
通过在不同含水量 (田间持水量的 6 0 % :对照处理 ;田间持水量的 2 5 0 % :淹水处理 )和不同温度 (2 0℃ ,2 5℃ ,30℃ )条件下的室内培养 ,对江苏省里下河地区池杉湿地林土壤的二价铁离子 (Fe2 + )浓度 ,氧化还原电位 (Eh)及 p H值进... 通过在不同含水量 (田间持水量的 6 0 % :对照处理 ;田间持水量的 2 5 0 % :淹水处理 )和不同温度 (2 0℃ ,2 5℃ ,30℃ )条件下的室内培养 ,对江苏省里下河地区池杉湿地林土壤的二价铁离子 (Fe2 + )浓度 ,氧化还原电位 (Eh)及 p H值进行了研究。结果表明 ,与对照处理相比 ,淹水土壤的 p H值和 Fe2 + 浓度明显提高 (P<0 .0 1) ,而 Eh值则明显降低 (P<0 .0 1)。在淹水条件下 ,高温处理的土壤 p H值和 Fe2 +浓度明显高于低温处理土壤 (P<0 .0 1) ,Eh值则相反。研究表明 ,土壤 Eh值与 p H值之间存在着密切的 3次方程式关系 (P<0 .0 0 1)。就里下河地区湿地林土壤而言 ,Eh值下降至 2 0 0 m V以下时 ,才会有大量的铁元素被还原为Fe2 +。 展开更多
关键词 湿地林土壤 二价铁离子 氧化还原电位 PH值
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掺杂及卤化调控富勒烯氧化还原电位的DFT研究
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作者 李健 孙冰花 +5 位作者 王春妮 李奥 吕祥鸿 王晨 代盼 白真权 《原子与分子物理学报》 CAS 北大核心 2025年第4期65-72,共8页
采用基于密度泛函理论(DFT)的模拟计算方法,分别计算了原始富勒烯C_(60)和11种单原子置换(掺杂及卤化)富勒烯材料C_(59)X(X=B、Si、N、P、As、O、S、Se、F、Cl、Br)的氧化还原电位、电子亲合能、分子轨道能级.其中,B、As、P、Si、N、Se... 采用基于密度泛函理论(DFT)的模拟计算方法,分别计算了原始富勒烯C_(60)和11种单原子置换(掺杂及卤化)富勒烯材料C_(59)X(X=B、Si、N、P、As、O、S、Se、F、Cl、Br)的氧化还原电位、电子亲合能、分子轨道能级.其中,B、As、P、Si、N、Se、S单原子置换导致氧化还原电位正移,B置换后增幅最高(3.655 V);F、Cl、Br、O单原子置换后,氧化还原电位均负移,F置换后降幅最大(2.476 V).在所考察的12种富勒烯分子中,C_(59)B和C_(59)F的电子亲和能(EA)分别为最小值(-3.901 eV)和最高值(-2.577 eV),二者分别具有最强和最弱的得电子倾向.在C_(59)B和C_(59)F中,B、F置换原子周围存在电荷偏聚,且B、F与周围C原子的成键主要来自于-2.5 eV和-7.5 eV能级附近2p电子的相互作用. 展开更多
关键词 密度泛函理论 富勒烯C_(60) 氧化还原电位 电子结构
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Elevated CO_(2) increases soil redox potential by promoting root radial oxygen loss in paddy field
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作者 Jie Li Han Zhang +5 位作者 Wenyi Xie Cheng Liu Xiaoyu Liu Xuhui Zhang Lianqing Li Genxing Pan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第2期11-20,共10页
Soil redox potential(Eh)plays an important role in the biogeochemical cycling of soil nutrients.Whereas its effect soil process and nutrients'availability under elevated atmospheric CO_(2) concentration and warmin... Soil redox potential(Eh)plays an important role in the biogeochemical cycling of soil nutrients.Whereas its effect soil process and nutrients'availability under elevated atmospheric CO_(2) concentration and warming has seldom been investigated.Thus,in this study,a field experiment was used to elucidate the effect of elevated CO_(2) concentration and warming on soil Eh,redox-sensitive elements and root radial oxygen loss(ROL).We hypothesized elevated CO_(2) and warming could alter soil Eh by promoting or inhibiting ROL.We found that soil Eh in the rhizosphere was significantly higher than that of non-rhizosphere.Elevated CO_(2) enhanced soil Eh by 11.5%,which corresponded to a significant decrease in soil Fe^(2+)and Mn^(2+)concentration.Under elevated CO_(2),the concentration of Fe^(2+)and Mn^(2+)decreased by 14.7%and 13.7%,respectively.We also found that elevated CO_(2) altered rice root aerenchyma structure and promoted rice root ROL.Under elevated CO_(2),rice root ROL increased by 79.5%and 112.2%for Yangdao 6 and Changyou 5,respectively.Warming had no effect on soil Eh and rice root ROL.While warming increased the concentration of Mn^(2+)and SO_(4)^(2-)by 4.9%and 19.3%,respectively.There was a significant interaction between elevated CO_(2) and warming on Fe^(2+)and Mn^(2+).Under elevated CO_(2),warming had no effect on the concentration of Fe^(2+)but decreased Mn^(2+)concentration significantly.Our study demonstrated that elevated atmospheric CO_(2) in the future could increase soil Eh by promoting rice root ROL,which will alter some soil nutrients'availability,such as Fe^(2+)and Mn^(2+). 展开更多
关键词 Atmospheric CO_(2)enrichment Global warming Soil redox potential FACE Rice root aerenchyma
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Kinetics and Modeling of Chemical Leaching of Sphalerite Concentrate Using Ferric Iron in a Redox-controlled Reactor 被引量:7
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作者 宋健 高玲 +2 位作者 林建群 吴洪斌 林建强 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第8期933-936,共4页
This work presents a study for chemical leaching of sphalerite concentrate under various constant Fe3+ concentrations and redox potential conditions. The effects of Fe3+ concentration and redox potential on chemical l... This work presents a study for chemical leaching of sphalerite concentrate under various constant Fe3+ concentrations and redox potential conditions. The effects of Fe3+ concentration and redox potential on chemical leaching of sphalerite were investigated. The shrinking core model was applied to analyze the experimental results. It was found that both the Fe3+ concentration and the redox potential controlled the chemical leaching rate of sphalerite. A new kinetic model was developed, in which the chemical leaching rate of sphalerite was proportional to Fe3+ concentration and Fe3+ /Fe2+ ratio. All the model parameters were evaluated from the experimental data. The model predictions fit well with the experimental observed values. 展开更多
关键词 SPHALERITE LEACHING kinetic model Fe3+ concentration redox potential LabVIEW
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Quantitative redox imaging biomarkers for studying tissue metabolic state and its heterogeneity 被引量:1
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作者 He N.Xu Lin Z.Li 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2014年第2期109-128,共20页
NAD+/NADH redox state has been implicated in many diseases such as cancer and diabetes aswell as in the regulation of embryonic development and aging,To fluorimetrically sssthemitochondrial redox state,Dr.Chance and c... NAD+/NADH redox state has been implicated in many diseases such as cancer and diabetes aswell as in the regulation of embryonic development and aging,To fluorimetrically sssthemitochondrial redox state,Dr.Chance and co-workers measured the fluorescence of NADH andoxidized flavoproteins(Fp)including favin-adenine-dinucleotide(FAD)and demonstrated theirratio(i.e.the redox ratio)is a sensitive indicator of the mitochondrial redox states.,The Chanceredox sca mer was built to simult aneously measure NADH and Fp in tisue at submilimeter scalein 3D using the freeze-trap protocol.This paper summarizes our recent research experience,development and new applications of the redox scanning technique in collaboration with Dr.Chance beginning in 2005.Dr.Chance initiated or actively involved in many of the projectsduring the last several years of his life.We advanced the redox scanning technigue by measuringthe nominal concentrations(in reference to the frozen solution standards)of the endogenousfuorescent analy tes,i.e.,[NADH]and[rp]to quantify the redox ratios in various biologicaltissues.The advancement has enabled us to identify an array of the redox indices as quantitativeimaging,biomarkers(including[NADH],[Fp],[Fp]/[NADH]+[Fp],[NADH]/[Fp],and theirstandard deviations)for studying some important biological questions on cancer and normaltsue metabolism.We found that the redox indices were asociated or changed with(NADH)tumorigenesis(cancer versus non-cancer of human breast tisue biopsies);(2)tumor metastaticpotential;(3)tumor glucose uptake;(4)tumor p53 stat us;(5)PI3K pathway activation in pre-malignant tissue;(6)therapeutic ffects on tumors;(7)embryonic stem cell diferentiation;(8)the heart under fasting,Together,our work demonstrated that the tisue redox indices obtainedfrom the redox scanning technique may provide usefil information about tisue met abolism and physiology status in normal and diseased tissues.The Chance redox scanner and other redoximaging techniques may have wide-ranging potential applications in many fields,such as cancer,diabetes,developmental process,mitochondrial diseases,neurodegenerative diseases,and aging. 展开更多
关键词 Tumor progresion MITOCHONDRIA met astasis met astatic potential pre-malignancy NADH FP FAD redox ratio
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A Bioenergetic-Redox Approach to the Effect of Live Yeast on Ruminal pH during Induced Acidosis in Dairy Cow
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作者 Jean Philippe Marden Corine Bayourthe +1 位作者 Eric Auclair Raymond Moncoulon 《American Journal of Analytical Chemistry》 2013年第10期60-68,共9页
The objective of this study was to evaluate the capacity of the live yeast (LY) Saccharomyces cerevisiae in optimizing ruminal pH and in understanding its mode of action during induced acidosis in dairy cow. Two non-l... The objective of this study was to evaluate the capacity of the live yeast (LY) Saccharomyces cerevisiae in optimizing ruminal pH and in understanding its mode of action during induced acidosis in dairy cow. Two non-lactating cannulated cows were used and offered twice daily a control diet (CD) consisting of 51% corn silage and 49% concentrates or a LY diet (LYD) composed of CD supplemented with 4 g of LY per cow and per day. Measurements of pH and redox potential (Eh) were continuously made at 1 h interval during an experimental period of 9 h per day. Samples of ruminal fluid were also taken at 2 h intervals for analyses of volatile fatty acids (VFA) and lactic acid. Oxygen partial pressure (logPO2) in the ruminal milieu was calculated from the Nernst equation, using either O2-H2O or lactate-propionate redox couples. The results showed an increase of 0.2 unit in ruminal pH when LYD was fed, which was accompanied by a mean difference in Eh of -20 mV with respect to CD. The logPO2 decreased significantly by 0.8 log unit for LYD when compared to CD. Concentrations of VFA and proportion of propionate were higher with LYD (114.4 mM and 17.1% total VFA) compared to CD (102.4 mM and 15.4% total VFA). Proportion of butyrate decreased (from 15.8% to 14.2% total VFA). Lactate concentration decreased by 55% on average. It is proposed that the stabilization of ruminal pH (>6) is the outcome of the LY ability to scavenge oxygen. In doing so, it increased the reducing capacity of the milieu favoring the production of total VFA and depressing the level of lactate. The LY oxygen-scavenging ability was put forward to account for the transformation of lactate (pKa = 3.86) into propionate (pKa = 4.87) under reduced ruminal conditions. 展开更多
关键词 LIVE YEAST OXYGEN FUGACITY pH redox potential
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养殖长茎葡萄蕨藻(Caulerpa lentillifera)污损微藻群落结构与水体pH和Eh变化的相关性
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作者 陈加雄 李伟滨 +2 位作者 黄乙书 廖小珊 林传旭 《湖北农业科学》 2022年第14期78-81,101,共5页
为探讨水体的pH和氧化还原电位(Eh)与长茎葡萄蕨藻(Caulerpa lentillifera)养殖过程中污损微藻群落变化的相关性,在养殖池中安装酸度计和氧化还原电位仪,在夹苗板处放置微藻附着试验塑料挂板45块,试验90 d。每隔10 d提取5板,合并分析微... 为探讨水体的pH和氧化还原电位(Eh)与长茎葡萄蕨藻(Caulerpa lentillifera)养殖过程中污损微藻群落变化的相关性,在养殖池中安装酸度计和氧化还原电位仪,在夹苗板处放置微藻附着试验塑料挂板45块,试验90 d。每隔10 d提取5板,合并分析微藻种群结构,记录同期pH和Eh。结果表明,共检出硅藻门4属4种,蓝藻门4属4种;pH前50 d呈上升趋势,后40 d趋于稳定,Eh在90 d内一直呈上升趋势;在前期pH和Eh较低的状态下硅藻类种群为优势群落,后期较高时则以蓝藻类种群为优势群落。pH和Eh与污损微藻种群结构具有显著相关性,与蓝藻种群呈正相关,与硅藻种群呈负相关。 展开更多
关键词 长茎葡萄蕨藻(Caulerpa lentillifera) 污损微藻 种群结构 pH 氧化还原电位(eh)
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WATER TABLE AND REDOX CONDITIONS IN DEEP TROPICAL PEAT
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作者 Hajah Dulima Jali 《湿地科学》 CSCD 2007年第1期13-19,共7页
Redox potential in the well developed tropical peat swamp in Brunei was studied for a year.Generally the redox potential measurements showed a large variation,ranging from-234 mV to 727 mV.The expected rise in redox v... Redox potential in the well developed tropical peat swamp in Brunei was studied for a year.Generally the redox potential measurements showed a large variation,ranging from-234 mV to 727 mV.The expected rise in redox values did not take place following the drop of water table during the dry months of June to September.The redox value at 100 cm depth indicated that the soil remained reduced throughout the year in spite of the lowering of water table below 150 cm in all sites during dry period.Similarly the redox values did not decrease rapidly following flooding when the water table rose to the surface.This phenomenon could be attributed to the topography of the peat dome which facilitated the fast lateral movement of water and thus promoted oxygen supply down the peat profile,though not great enough to reach the 100 cm depth.The rapid lateral flow of water in the outer Alan batu site facilitated aeration,but in the inner sites remained which was reduced because of the slower water movement.The slower initiation of the reducing condition was likely due to the presence of nitrate which has accumulated as a result of ammonium oxidation during the relatively long aerobic period.Differences in the distribution of redox potential with depth are possibly explained by the different permeability of peat affecting flow patterns and residence time of water.The nature and compactibility of the peat might have slowed the diffusion rates of O2 into the lower layer.Though the bulk density of the peat was low,the composition of the peat might influence the peat permeability and hydraulic conductivity.The tree trunks are not decomposed or large branches must have lowered permeability compared to the other peat material. 展开更多
关键词 文莱 热带泥煤湿地 地下水位 氧化还原条件 植物残体
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Deterioration in Hemodynamics Reaction, Baroreflex Sensitivity, Sympathetic Nerve Activity and Redox State of Thoracic Aorta in the Experimental Model of Nitrate Tolerance and Its Pharmacological Correction
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作者 Nikoloz V. Gongadze Tamara D. Kezeli +4 位作者 Galina V. Sukoyan Zaza Chapichadze Nino M. Dolidze Makrine Mirziashvili Mariam Chipashvili 《Pharmacology & Pharmacy》 2016年第1期81-88,共8页
Continuous treatment with organic nitrates causes nitrate tolerance and provides evidence for a relationship between mitochondrial complex 1 activity and mitochondrial aldehyde dehydrogenase-2 (ALDH-2) with disturbanc... Continuous treatment with organic nitrates causes nitrate tolerance and provides evidence for a relationship between mitochondrial complex 1 activity and mitochondrial aldehyde dehydrogenase-2 (ALDH-2) with disturbances of the hemodynamics reaction during nitroglycerin (NTG) tolerance (NTGT). The purpose of this study was the evaluation of efficacy of original oxidized form NAD-containing drug, NADCIN<sup>&reg</sup>, on hemodynamic reactions, baroreflex sensitivity (BRS) and reflex control of splanchnic sympathetic nerve activity (SSNA), level of redox-potential, activity of ALDH-2 and superoxide anion generation in aortic tissue in rat model of NTGT. Five groups (7 - 9 each) of male Wistar rats, including control, acute i.v. NTG (150 mcg/kg) administration, NTG tolerance NTGT treatment with NADCIN<sup>&reg</sup> 8 mg/kg and methylene blue (MB, 2.5 mg/kg) were used. NTGT in rats was accompanied with the greatly attenuation of hemodynamics reaction, BRS, the decreasing of the ability to reflex control of SSNA without pronounce overexpression of endothelin-1 in vessels (aorta). In NTGT rats i.v. NTG along induced less hypotensive reactions and alterations in heart period vs single NTG treated group, more expressively decreased BRS (-34%) and reflex control of SSNA (-18%). NADCIN<sup>&reg</sup> significantly inhibits tolerance-inducing properties of the prolonged nitroglycerin infusion (max decrease of blood pressure response to nitroglycerin injection, % of normal controls: NTGT 51.2%, NADCIN<sup>&reg</sup> 91.6%, MB 55.8%). NADCIN<sup>&reg</sup> in NTGT rats after NTG i.v. administration increased reduced BRS (+37.8%, p < 0,05), reflex control of SSNA (+29.4%, p < 0.05) and reversed the decreasing of NAD/NADH ratio, ALDH-2 activity and decreasing in superoxide generation in thoracic aortic tissue. Thus, course treatment with NADCIN<sup>&reg</sup> of NTGT rats restores hemodynamics changes, BRS and SSNA throughout the increasing of redox-potential NAD/NADH and cessates the NTGT developing. 展开更多
关键词 Experimental Model of Nitroglycerin Tolerance Baroreflex Sensitivity Aldehyde Dehydrogenase redox-potential Splanchnic Sympathetic Nerve Activity
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污水污泥磷形态亚临界水热转化研究
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作者 郑晓园 蔡炎嶙 +2 位作者 应芝 王波 豆斌林 《化工学报》 EI CSCD 北大核心 2024年第8期2970-2982,共13页
利用外源氮气加压的方式实现了水热过程温度-压力解耦,考察了亚临界水热过程有机物组成和初始水热压力对污水污泥中磷形态转化的影响,同时验证了该过程中生成蓝铁矿的可行性。污泥模化物水热实验表明,初始水热压力强化了磷富集于水热炭... 利用外源氮气加压的方式实现了水热过程温度-压力解耦,考察了亚临界水热过程有机物组成和初始水热压力对污水污泥中磷形态转化的影响,同时验证了该过程中生成蓝铁矿的可行性。污泥模化物水热实验表明,初始水热压力强化了磷富集于水热炭中,促进了葡萄糖和蛋白质转化为还原性物质,从水热炭中观察到较强的蓝铁矿X射线衍射峰。城市污泥水热实验表明,水热处理有利于磷富集于水热炭中,压力强化了磷向水热炭迁移,总磷(TP)浓度从31.45 mg/g(0.1MPa)提升到39.68 mg/g(1.0 MPa)。水热温度110℃时,增加初始水热压力促进了污泥中Fe(Ⅲ)-P向Fe(Ⅱ)-P转化,1.0 MPa水热炭中Fe(Ⅱ)-P浓度为原始污泥的6.31倍。提高初始水热压力促进了污泥中碳水化合物和蛋白质等有机物分解形成有机酸,使得水热液pH降低;蛋白质转化导致水热液中NH^(+)_(4)-N浓度升高。同时,水热液氧化还原电位升高,说明有机酸等还原性物质被消耗,促进了三价铁还原,致使水热炭中Fe(Ⅱ)-P浓度升高,有利于蓝铁矿生成。增压条件下,污泥水热炭XRD衍射图中观察到了蓝铁矿的特征峰,说明采用温度-压力解耦水热方法可以生成蓝铁矿。本研究为污泥磷资源回收提供了新思路。 展开更多
关键词 温度-压力解耦 氧化还原电位 还原 废物处理 回收
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