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Repressing iron overload ameliorates central poststroke pain via the Hdac2-Kv1.2 axis in a rat model of hemorrhagic stroke
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作者 He Fang Mengjie Li +6 位作者 Jingchen Yang Shunping Ma Li Zhang Hongqi Yang Qiongyan Tang Jing Cao Weimin Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2708-2722,共15页
Thalamic hemorrhage can lead to the development of central post-stroke pain.Changes in histone acetylation levels,which are regulated by histone deacetylases,affect the excitability of neurons surrounding the hemorrha... Thalamic hemorrhage can lead to the development of central post-stroke pain.Changes in histone acetylation levels,which are regulated by histone deacetylases,affect the excitability of neurons surrounding the hemorrhagic area.However,the regulato ry mechanism of histone deacetylases in central post-stroke pain remains unclea r.Here,we show that iron overload leads to an increase in histone deacetylase 2expression in damaged ventral posterolateral nucleus neurons.Inhibiting this increase restored histone H3 acetylation in the Kcna2 promoter region of the voltage-dependent potassium(Kv)channel subunit gene in a rat model of central post-stroke pain,thereby increasing Kcna2expression and relieving central pain.However,in the absence of nerve injury,increasing histone deacetylase 2 expression decreased Kcna2expression,decreased Kv current,increased the excitability of neurons in the ventral posterolateral nucleus area,and led to neuropathic pain symptoms.Moreover,treatment with the iron chelator deferiprone effectively reduced iron overload in the ventral posterolateral nucleus after intracerebral hemorrhage,reversed histone deacetylase 2 upregulation and Kv1.2 downregulation,and alleviated mechanical hypersensitivity in central post-stroke pain rats.These results suggest that histone deacetylase 2 upregulation and Kv1.2 downregulation,mediated by iron overload,are important factors in central post-stroke pain pathogenesis and co uld se rve as new to rgets for central poststroke pain treatment. 展开更多
关键词 central post-stroke pain hemorrhagic stroke histone deacetylase iron overload voltage-gated potassium ion channel 1.2
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Oxidation of As(Ⅲ) by potassium permanganate 被引量:11
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作者 LI Na FAN Maohong +3 位作者 Van Leeuwen Johannes Saha Basudeb YANG Hongqun HUANG C. P. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第7期783-786,共4页
The oxidation of As(Ⅲ) with potassium permanganate was studied under conditions including pH, initial As(Ⅲ) concentration and dosage of Mn(Ⅶ). The results have shown that potassium permanganate was an effecti... The oxidation of As(Ⅲ) with potassium permanganate was studied under conditions including pH, initial As(Ⅲ) concentration and dosage of Mn(Ⅶ). The results have shown that potassium permanganate was an effective agent for oxidation of As(Ⅲ) in a wide pH range. The pH value of tested water was not a significant factor affecting the oxidation of As(Ⅲ) by Mn(Ⅲ). Although theoretical redox analyses suggest that Mn(Ⅶ) should have better performance in oxidization of As(Ⅲ) within lower pH ranges, the experimental results show that the oxidation efficiencies of As(Ⅲ) under basic and acidic conditions were similar, which may be due to the adsorption of As(Ⅲ) on the Mn(OH)2 and MnO2 resulting from the oxidation of As(Ⅲ). 展开更多
关键词 ARSENITE ARSENATE OXIDATION potassium permanganate
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Novel Application of Vacuum Sealing Drainage with Continuous Irrigation of Potassium Permanganate for Managing Infective Wounds of Gas Gangrene 被引量:14
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作者 胡宁 吴星火 +7 位作者 刘融 杨述华 黄玮 蒋电明 吴强 夏天 邵增务 叶哲伟 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2015年第4期563-568,共6页
Summary: Traumatic gas gangrene is a fatal infection mainly caused by Clostridium perfringens. It is a challenge to manage gas gangrene in open wounds and control infection after debridement or amputa- tion. The aim ... Summary: Traumatic gas gangrene is a fatal infection mainly caused by Clostridium perfringens. It is a challenge to manage gas gangrene in open wounds and control infection after debridement or amputa- tion. The aim of the present study was to use vacuum sealing drainage (VSD) with continuous irrigation of potassium permanganate to manage infective wounds of gas gangrene and observe its clinical effi- cacy. A total of 48 patients with open traumatic gas gangrene infection were included in this study. Am- putations were done for 27 patients, and limb salvage procedures were performed for the others. After amputation or aggressive debridement, the VSD system, including polyvinyl alcohol (PVA) foam dress- ing and polyurethane (PU) film, with continuous irrigation of 1:5000 potassium permanganate solutions, was applied to the wounds. During the follow-up, all the patients healed without recurrence within 8-18 months. There were four complications. Cardiac arrest during amputation surgery occurred in one pa- tient who suffered from severe septic shock. Emergent resuscitation was performed and the patient re- turned to stable condition. One patient suffered from mixed infection of Staphylococcal aureus, and a second-stage debridement was performed. One patient suffered from severe pain of the limb after the debridement. Exploratory operation was done and the possible reason was trauma of a local peripheral nerve. Three cases of crush syndrome had dialysis treatment for concomitant renal failure. In conclusion, VSD can convert open wound to closed wound, and evacuate necrotic tissues. Furthermore, potassium permanganate solutions help eliminate anaerobic microenviroument and achieve good therapeutic effect on gas gangrene and mixed infection. VSD with continuous irrigation of potassium permanganate is a novel, simple and feasible alternative for severe traumatic open wounds with gas gangrene infection. 展开更多
关键词 vacuum sealing drainage potassium permanganate IRRIGATION gas gangrene TRAUMA
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Effects of chlorine content and position of chlorinated phenols on their oxidation kinetics by potassium permanganate 被引量:4
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作者 ZHANGJin LIGui-bai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第3期342-345,共4页
Chlorine content and position of chlorinated phenols have many significant effects on the reactivity of oxido-reduction. The effects of chlorine content and position of chlorinated phenols on their oxidation kinetics ... Chlorine content and position of chlorinated phenols have many significant effects on the reactivity of oxido-reduction. The effects of chlorine content and position of chlorinated phenols on their oxidation kinetics by potassium permanganate were evaluated through different kinetics studies. Since chlorine was an electron withdrawing atom, the substitution of chlorine on the aromatic ring decreased the oxidation rate constant by σ-electron withdrawing conductive effect. The substitution of chlorine at ortho or para position on the aromatic ring increased the oxidation rate constant by π-electron donating conjugative effect, and the conjugative effect could counteract the negative impact of the conductive effect to some extent. On the other hand, the substitution of chlorine at ortho position on the aromatic ring decreased the oxidation rate constant by steric hindrance effect. The oxidation rate constants of phenol and chlorinated phenols studied decreased as follow order: 4-chlorophenol>2,4-dichlorophenol>phenol>2,6-dichlorophenol. 展开更多
关键词 oxidation KINETICS PHENOL 4-CHLOROPHENOL 2 4-DICHLOROPHENOL 2 6-DICHLOROPHENOL potassium permanganate
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Flow-injection chemiluminescence determination of tryptophan using galangin-potassium permanganate-polyphosphoric acid system 被引量:2
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作者 Hui Chen Li Li Min Zhou Yong Jun Ma 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第2期203-206,共4页
A high sensitive flow-injection chemiluminescence (FI-CL) method for the determination of tryptophan has been developed. The method is based on the chemiluminescence reaction of galangin-potassium permanganate-trypt... A high sensitive flow-injection chemiluminescence (FI-CL) method for the determination of tryptophan has been developed. The method is based on the chemiluminescence reaction of galangin-potassium permanganate-tryptophan in polyphosphoric acid (PPA) media. Under the optimized conditions, tryptophan was determined in the range 0.05-10 μg/mL with the detection limit (3tr) of 5.0 × 10^-3 μg/mL. The relative standard deviation (RSD) was 1.0% for 11 replicate determinations of 1.0 μg/mL tryptophan. Three synthetic samples were determined selectively with recoveries in the range from 99.6% to 102.0% in the presence of other amino acids. 展开更多
关键词 CHEMILUMINESCENCE FLOW-INJECTION GALANGIN potassium permanganate TRYPTOPHAN
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Wet carbon-based solid acid/potassium permanganate as an efficient heterogeneous reagents for oxidation of alcohols under mild conditions 被引量:1
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作者 Arash Shokrolahi Abbas Zali Mohammad Hossein Keshavarz 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第11期1274-1276,共3页
Wet carbon-based solid acid and potassium permanganate were used as new reagents for oxidation of alcohols to their corresponding aldehydes and ketones in heterogeneous mixtures. The experiments were done moderately a... Wet carbon-based solid acid and potassium permanganate were used as new reagents for oxidation of alcohols to their corresponding aldehydes and ketones in heterogeneous mixtures. The experiments were done moderately at mild condition and high yields in suitable times were obtained. 展开更多
关键词 Carbon-based solid acid potassium permanganate OXIDATION ALCOHOLS
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Preliminary Analyses of Controlled Release of Potassium Permanganate Encapsulated in Polycaprolactone 被引量:1
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作者 Niya S. King Stephanie Luster-Teasley Clayton J. Clark II 《Journal of Water Resource and Protection》 2021年第1期32-43,共12页
Potassium permanganate (KMnO<sub>4</sub>) has been used widely as an oxidant for remediation of contaminated soil and water systems. The present study evaluates the release of this oxidant from Polycaprola... Potassium permanganate (KMnO<sub>4</sub>) has been used widely as an oxidant for remediation of contaminated soil and water systems. The present study evaluates the release of this oxidant from Polycaprolactone (PCL) polymer as part of a patented controlled release process (CRP) to be applied for targeted removal of contaminants from water. KMnO<sub>4</sub> was encapsulated into PCL at a 1:5 oxidant to polymer ratio and placed in batch reactor systems with reagent water to be evaluated over a 96 hour period. SEM images showed that over time, the number of cavities and their sizes increased on the waxy surface of the PCL polymer. The experimental data from the release of KMnO<sub>4</sub> from PCL was found to fit non-Fickian diffusion model after dissolution (R<sup>2</sup> = 0.93) similar to other systems that describe the dispersal of other oxidants from wax matrices. In addition, the model parameters for data of this present study were also found to be comparable to previous release studies with the same oxidant encapsulated in different wax matrices at similar ratios. Overall, the similarity of release data between the diversity of polymers shows that the controlled release biodegradable polymer utilizing PCL provides effective release of the KMnO<sub>4</sub> with the added benefit biodegradable nature of PCL. 展开更多
关键词 potassium permanganate CONTROLLED-RELEASE ENCAPSULATION KINETICS
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Effect of operating conditions and potassium content on Fischer-Tropsch liquid products produced by potassium-promoted iron catalysts 被引量:1
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作者 Francisco E.M.Farias Fernando G.Sales Fabiano A.N.Fernandes 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第2期175-178,共4页
The dependencies of Fischer-Tropsch synthesis liquid hydrocarbon product distribution on operating pressure and temperature have been studied over three potassium-promoted iron catalysts with increasing potassium mola... The dependencies of Fischer-Tropsch synthesis liquid hydrocarbon product distribution on operating pressure and temperature have been studied over three potassium-promoted iron catalysts with increasing potassium molar content. The study followed an experimental planning and the results were analyzed based on surface response methodology. The effects of different operating conditions and potassium contents on the liquid product distribution were compared based on number average carbon number and dispersion. Results showed that high pressures (25 to 30 arm) favored the production of waxes that could be converted into liquid fuels through hydrocracking, while greater direct selectivity towards diesel was favored by low pressure (20 arm) using catalysts with low potassium to iron molar ratios. The liquid product distribution produced using an iron catalyst with high potassium content presented higher number-average number of carbons when compared to the distribution obtained using an iron catalyst with low potassium content. 展开更多
关键词 Fischer-Tropsch synthesis liquid fuels iron-based catalyst potassium
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Effects of Potassium Permanganate on Respiratory Movement in Carassius auratus under Different Conditions
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作者 XIE Song CHEN Li-wei 《Animal Husbandry and Feed Science》 CAS 2010年第10期36-38,共3页
[ Objective] To observe the effects of potassium permanganate on respiratory rate and cough frequency of Carassius auratus in different conditions. [Method] According to the simple factor design of experiment, the res... [ Objective] To observe the effects of potassium permanganate on respiratory rate and cough frequency of Carassius auratus in different conditions. [Method] According to the simple factor design of experiment, the respiratory rate and cough frequency of Carassius auratus were recorded. The factors included concentration of potassium permanganate, temperature, duration time and pH values. [ Result] The respiratory rate and cough frequency of Carassius auratus were increased and then decreased with the increasing concentrations of potassium permanganate, rising temperature, and duration of medicated bath. The Carassius auratus had the best respiratory function at pH 7.0. The strong acid and strong alkali caused lesions and inhibited the respiratory function of Carassius auratus. [ Conclusion ] The potassium permanganate at different concentrations may have an impact on the cough frequency and respiratory rate of Carassius auratus. 展开更多
关键词 potassium permanganate Respiratory rate Cough frequency Carassius auratus
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Suicidal ingestion of potassium permanganate
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作者 Esin Korkut Ayhan Saritas +3 位作者 Yusuf Aydin Semih Korkut Hayati Kandis Davut Baltaci 《World Journal of Emergency Medicine》 CAS 2013年第1期73-74,共2页
BACKGROUND:Potassium permanganate is used clinically as an antiseptic and antifungal agent.Ingestion of potassium permanganate may result in damage to the upper gastrointestinal tract.Burns and ulceration of the mouth... BACKGROUND:Potassium permanganate is used clinically as an antiseptic and antifungal agent.Ingestion of potassium permanganate may result in damage to the upper gastrointestinal tract.Burns and ulceration of the mouth,esophagus and stomach occur due to its action.Emergency endoscopy is useful to assess the severity of damage and also to guide management.METHODS:We reported a patient presenting to the emergency department after suicidal ingestion of potassium permanganate.RESULTS:After treatment,the patient was discharged home on the 7th day after admission.CONCLUSION:Early emergency endoscopy should be considered to determine the extent of upper gastrointestinal damage in the emergency department. 展开更多
关键词 Emergency endoscopy Gastric damage SUICIDE potassium permanganate
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Low Plasma Potassium and High Iron Levels Increased the Risk of Dyslipidemia among Non-Diabetic Taxi-Motorbike Drivers Living and Working in Cotonou, Benin
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作者 Patrice Hodonou Avogbe Ambaliou Sanni 《Open Journal of Endocrine and Metabolic Diseases》 CAS 2022年第7期159-175,共17页
Non-traditional cardiovascular risk factors such as iron and potassium may play a role in lipid metabolism. However, information on this association is lacking in populations of Benin. This study evaluated the associa... Non-traditional cardiovascular risk factors such as iron and potassium may play a role in lipid metabolism. However, information on this association is lacking in populations of Benin. This study evaluated the associations between plasma iron and potassium levels and risk of dyslipidemia among taxi-motorbike drivers (TMDs) in Cotonou. We conducted a cross-sectional study on 134 males TMDs aged ≥20 years old, of whom 39 (29.1%) had dyslipidemia. Plasma biochemistry including measurements of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C), iron, and potassium were performed. Dyslipidemia was defined as any or combinations of the following: TC > 5.2 mmol/L, LDL-C > 3.4 mmol/L, TG > 1.7 mmol/L, and HDL-C 18.8 μmol/L) to the 1<sup>st</sup> tertile of plasma iron (<13.6 μmol/L) was 3.85, (95% CI: 1.20 - 12.35, p = 0.023). We observed similar patterns of association in a subgroup analysis restricted to normotensive patients, although the estimates lacked statistical significance. Our findings also revealed that the risk of dyslipidemia decreased when plasma potassium levels increased. The OR (95% CI) for dyslipidemia comparing the 2<sup>nd</sup> tertile (4.4 - 4.8 μmol/L) to the 1<sup>st</sup> tertile (<4.3 μmol/L) of potassium was 0.31 (0.11 - 0.86, p = 0.025). Interestingly, the risk of dyslipidemia decreased progressively (81% to 86%) and significantly across plasma potassium tertiles when restricting analysis to normotensive patients. The ORs (95% CI) for dyslipidemia comparing the 2<sup>nd</sup> and 3<sup>rd</sup> tertiles to the 1<sup>st</sup> tertile of plasma potassium were 0.19 (0.04 - 0.87, p = 0.032) and 0.14 (0.02 - 0.93, p = 0.043). In conclusion, our study shows that higher plasma iron and low potassium levels are significant predictors of dyslipidemia in TMDs. As such, the findings have public health implications for predicting and preventing dyslipidemia and associated cardiometabolic diseases. However, longitudinal studies are needed to determine if disturbances in iron and potassium levels, even within the normal range, are precursors or consequences of dyslipidemia. 展开更多
关键词 Cotonou DYSLIPIDEMIA iron potassium Taxi-Motorbike Drivers
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Influence of Potassium Nutrition and Exogenous Organic Acids on Iron Uptake by Monocot and Dicot Plants
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作者 Eman F. A. Awad-Allah Ibrahim H. Elsokkary 《Open Journal of Soil Science》 2020年第10期486-500,共15页
Iron (Fe) is a vital element for the survival and proliferation of all plants;therefore, Fe-biofortification by the application of chemical and organic fertilizers is being as an effective approach to fight hidden hun... Iron (Fe) is a vital element for the survival and proliferation of all plants;therefore, Fe-biofortification by the application of chemical and organic fertilizers is being as an effective approach to fight hidden hunger retards the growth and development of crop plants. Two experiments were carried out to investigate the effect of potassium and exogenous organic acids on iron uptake by two different plants<span>:</span><span> one is monocotyledon</span><span>,</span><span><span> maize (<i></i></span><i><i><span>Zea mays</span></i><span></span></i> L.) and the second is dicotolydon pea (<i></i></span><i><i><span>Pisum sativum</span></i></i><span> L.) grown under controlled conditions. The seedlings were grown in sand culture in a greenhouse experiment and irrigated with one-tenth strength modified nutrient solution of Hoagland and Arnon as a base solution (pH 7.5), containing different iron treatments (0, 1, and 5 ppm as FeSO</span><sub>4</sub>·<span>7H</span><sub><span>2</span></sub><span>O) combined with potassium nutrition (0, 5, 10, and 50 ppm as K</span><sub><span>2</span></sub><span>SO</span><sub><span>4</span></sub><span>). After 30 days, the best interaction treatment was selected for further experiment including 5.0 ppm Fe as FeSO</span><sub>4</sub><sup>.</sup><span>7H</span><sub><span>2</span></sub><span>O and 50 ppm K as K</span><sub><span>2</span></sub><span>SO</span><sub><span>4</span></sub><span> in combination with 1</span><span> </span><span>×</span><span> </span><span><span>10<sup>-</sup></span><sup><span>5</span></sup><span> mole/liter of one </span></span><span>of </span><span>the following organic acids: Citric acid, Oxalic acid, Formic acid, Acetic acid, Propionic acid, Tartaric acid, Succinic acid, Fumaric acid, Malic acid, Glutamic acid, besides the free organic acid nutrient solution as a control. Results revealed that the interaction between 5.0 ppm Fe and 50 ppm K was the best interaction treatment for increasing biomass production and iron uptake of maize and pea seedlings under applied condition. Furthermore, exogenous application of organic acids improves uptake and translocation of nutrient such as iron, potassium and phosphorus by the maize and pea plants. In conclusion, potassium nutrition and exogenous organic acids have the potential to stimulate Fe-uptake of monocot and dicot plants and mediate iron-biofortified crops.</span> 展开更多
关键词 potassium Organic Acids iron Uptake BIOFORTIFICATION SUSTAINABILITY
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Comparison of Release Efficiencies for the Controlled-Release of Potassium Permanganate in Polycaprolactone
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作者 Niya Sade King Stephanie Luster-Teasley Clayton Jerie Clark II 《Journal of Environmental Protection》 2022年第3期277-288,共12页
The application of controlled release materials in tandem with chemical oxidants has become an emerging topic within the field of environmental treatment. The controlled release kinetic and mechanistic relationship be... The application of controlled release materials in tandem with chemical oxidants has become an emerging topic within the field of environmental treatment. The controlled release kinetic and mechanistic relationship between these components is important to understand a controlled release system. Potassium permanganate (KMnO<sub>4</sub>) was used as the encapsulated material integrated into polycaprolactone (PCL) producing controlled release biodegradable polymer (CRBP) pellets. In this study, batch experiments were used to examine the release kinetics from the discharge of the pelletized encapsulated oxidant into aqueous systems at various KMnO<sub>4</sub>:PCL ratios of 1:5, 2:5, and 3:5 by mass. Experimental results indicated as the amount of KMnO<sub>4</sub> in the PCL polymer pellets increased, a greater fraction of the oxidant was released as a function of time. The resultant data best fit a linearized diffusion model equation. Additionally, a comparison-controlled release study was conducted that contained the same oxidant at similar mass ratios. Release kinetics determined from this study could lead to effective implementation of CRBP systems and could suggest that CRBP encapsulated with KMnO<sub>4</sub> could serve as a promising controlled release technology in a long-term and controlled manner. 展开更多
关键词 potassium permanganate POLYCAPROLACTONE Controlled Release Biodegradable Polymer (CRBP)
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Effect of potassium permanganate dosing position on the performance of coagulation/ultrafiltration combined process 被引量:3
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作者 He Zhao Liang Wang +3 位作者 Hongwei Zhang Xiaona Wu Bin Zhao Fei Han 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第1期89-95,共7页
The effects of potassium permanganate(KMnO_4)dosing position on the natural organic matter(NOM)removal as well as membrane fouling were investigated in the coagulation/ultrafiltration combined process.KMnO_4 oxidation... The effects of potassium permanganate(KMnO_4)dosing position on the natural organic matter(NOM)removal as well as membrane fouling were investigated in the coagulation/ultrafiltration combined process.KMnO_4 oxidation altered the NOM characteristics in terms of hydrophobicity and molecular weight,and destroyed humic substances originated from terraneous organisms in raw water.The optimal KMnO_4 dosage was 0.5 mg·L^(-1) in the peroxidation enhanced coagulation process with respect to the dissolved organic carbon(DOC)removal.When KMnO_4 was dosed into both upstream and downstream of coagulation,namely in the proposed twoposition dosing mode,coagulation and KMnO_4 oxidation worked individually on the apparent DOC removal.However,compared to the KMnO_4 addition prior to or after coagulation,the two-position dosing mode dramatically alleviated membrane fouling and reduced fouling irreversibility.This was attributed to the change of NOM characteristics as a result of KMnO_4 addition prior to coagulation and the presence of MnO_2 on membrane surface as a result of KMnO_4 addition prior to ultrafiltration.This work may provide useful information for the application of KMnO_4 oxidation in the coagulation/ultrafiltration combined system. 展开更多
关键词 高锰酸盐 COA 位置 KMNO4 凝结过程 表演 自然有机物
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Effects of Potassium and Manganese Promoters on Nitrogen-Doped Carbon Nanotube-Supported Iron Catalysts for CO_2 Hydrogenation 被引量:6
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作者 Praewpilin Kangvansura Ly May Chew +6 位作者 Chanapa Kongmark Phatchada Santawaja Holger Ruland Wei Xia Hans Schulz Attera Worayingyong Martin Muhler 《Engineering》 SCIE EI 2017年第3期385-392,共8页
氮掺杂碳纳米管(NCNTs)作为载体负载铁(Fe)纳米颗粒,可应用于CO_2多相催化加氢反应(633 K和25 bar)。当将钾(K)和锰(Mn)作为助催化剂时,Fe/NCNT展现出优异的CO_2加氢性能,在体积空速(GHSV)为3.1 L·g^(–1)·h^(–1)时转化率可... 氮掺杂碳纳米管(NCNTs)作为载体负载铁(Fe)纳米颗粒,可应用于CO_2多相催化加氢反应(633 K和25 bar)。当将钾(K)和锰(Mn)作为助催化剂时,Fe/NCNT展现出优异的CO_2加氢性能,在体积空速(GHSV)为3.1 L·g^(–1)·h^(–1)时转化率可达34.9%。当使用K作为助催化剂时,反应对烯烃和短链烷烃具有高的选择性。当K和Mn同时作为助催化剂时,其催化活性能够稳定地维持60 h。助催化剂Mn的结构效应通过X射线衍射、氢气程序升温还原以及近边X射线吸收精细结构进行表征。助催化剂Mn不仅能够稳定中间态FeO,且能降低程序升温还原的起始温度。通过探针反应NH3的催化分解来表征助催化剂效应。当K和Mn作为助催化剂时,Fe/NCNT具有最好的催化活性。在还原条件下,当K作为助催化剂时,Fe/NCNT具有最优异的热稳定性。 展开更多
关键词 CO_2加氢 铁基催化剂 n型碳纳米管 Mn助剂 K助剂
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Phenol Removal from Water with Potassium Permanganate Modified Granular Activated Carbon
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作者 Jin Zhang 《Journal of Environmental Protection》 2013年第5期411-417,共7页
In order to improve adsorption capacity of granular activated carbon (GAC), potassium permanganate was used to react with GAC to change the surface properties and improve the adsorption capacity of GAC. By batch exper... In order to improve adsorption capacity of granular activated carbon (GAC), potassium permanganate was used to react with GAC to change the surface properties and improve the adsorption capacity of GAC. By batch experiments, improvement of adsorption capacity of potassium permanganate modified GAC (GACM) was studied. The influence of adsorption time, temperature, ratio of phenol with GAC/GACM, initial concentration of phenol and pH on adsorption efficiency of GACM was studied. The results showed that modified by potassium permanganate, the adsorption capacity of GAC improved to a higher level. The removal efficiency of phenol increased to about 20%. 展开更多
关键词 MODIFIED GRANULAR ACTIVATED Carbon potassium permanganate PHENOL Adsorption
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Developed New Procedure for Low Concentrations of Hydrazine Determination by Spectrophotometry: Hydrazine-Potassium Permanganate System
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作者 S. Ganesh Fahmida Khan +3 位作者 M. K. Ahmed P. Velavendan N. K. Pandey U. Kamachi Mudali 《Journal of Analytical Sciences, Methods and Instrumentation》 2012年第2期98-102,共5页
An indirect, sensitive and accurate method for the determination of trace amounts of hydrazine is described. In this proposed the spectrophotometric method is based on its reduction properties of hydrazine with a know... An indirect, sensitive and accurate method for the determination of trace amounts of hydrazine is described. In this proposed the spectrophotometric method is based on its reduction properties of hydrazine with a known concentration of potassium permanganate to reduce the colour. The absorbance of unreduced permanganate is measured the colour difference at different wavelengths 546 and 526 nm which show an absorption spectrum with hydrazine. Hydrazine can be determined in the range of 100 - 700 μg/ml with correlation coefficient of 0.999 and relative standard deviation 1%. The method is successfully applied for the determination of hydrazine in water streams in nuclear reactors/purex process/boiler water and polluted water samples. 展开更多
关键词 Hydrazine/potassium permanganate UV-VIS SPECTROPHOTOMETRY Reducing Property Water STREAMS Nuclear Reactors
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Comparative study on combined preoxidation by potassium permanganate composites with chlorine and preozonation for enhancing coagulation
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作者 梁恒 郑文禹 +2 位作者 公维佳 任南琪 李圭白 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第6期849-853,共5页
Comparative pilot tests were conducted to investigate the coagulation-aid effects of the combined preoxidation by potassium permanganate composites (PPC) with chlorine and preozonation. And the synergistic mechanism o... Comparative pilot tests were conducted to investigate the coagulation-aid effects of the combined preoxidation by potassium permanganate composites (PPC) with chlorine and preozonation. And the synergistic mechanism of combined preoxidation was discussed. Results showed that 1.0 mg/L PPC with 2.0 mg/L chlorine could further improve the quality of treated water, as indicated by residual turbidity, TOC and algae. The enhanced efficiency could be explained by the synergistic effect of the preoxidants themselves, or the effect of chlorine and the intermediate such as hydrous manganese dioxide, which was generated by potassium permanganate, the main ingredient of PPC. 展开更多
关键词 臭氧预氧化 高锰酸钾 复合材料 凝血 合并 PPC 试验测试
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Effect of Potassium Addition on Coprecipitated Iron Catalysts for Fischer-Tropsch Synthesis Using Bio-oil-syngas
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作者 Zhao-xiang Wang Ting Dong Tao Kan Quan-xin Li 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第2期141-150,共10页
在为 Fischer-Tropsch 合成(英尺) 的一同沉淀的铁催化剂的活动和选择的钾增加和钾内容的效果在 1.5 MPa 在一个固定的床反应堆被学习, 300 吗??
关键词 共沉淀技术 催化剂 合成方法
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Removal of iron from ilmenite by KOH leaching-oxalate leaching method 被引量:5
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作者 WANG Yuanbo QI Tao +1 位作者 CHU Jinglong ZHAO Wei 《Rare Metals》 SCIE EI CAS CSCD 2010年第1期9-15,共7页
Oxalic acid was used for the removal of iron from the intermediates of ilmenite leached by KOH liquor. Various parameters, such as pH, temperature, initial oxalate concentration, and illumination were investigated. Me... Oxalic acid was used for the removal of iron from the intermediates of ilmenite leached by KOH liquor. Various parameters, such as pH, temperature, initial oxalate concentration, and illumination were investigated. Meanwhile, it was found that orthorhombic crystal Ti2O2(OH)2(C2O4)-H2O formed as the leaching proceeded. Scanning electronic microscope (SEM) images implied that the formation of Ti2O2(OH)2(C2O4).H2O with good crystallinity proceeded through three stages. Calcining Ti2O2(OH)2(C2O4)·H2O, anatase (350℃) or mtile (550℃) type TiO2 was obtained, respectively. Element analysis found that the calcined product contained 94.9% TiO2 and 2.5% iron oxide, but only about 1600 ppm dissolvable iron oxide was left, which indicates that oxalic acid was comparatively effective on iron oxide removal from the intermediates. Finally, an improved route was proposed for the upgrading of ilmenite into mtile. 展开更多
关键词 ILMENITE iron removal titanium oxide OXALATE potassium hydroxide KOH leaching
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