Fixed-bed operating experimental column conditions were studied to evaluate the performance of brick from Bangui Region (in Central African Republic), coated with iron oxyhydroxide (ferrihydrite) for the removal of ir...Fixed-bed operating experimental column conditions were studied to evaluate the performance of brick from Bangui Region (in Central African Republic), coated with iron oxyhydroxide (ferrihydrite) for the removal of iron(II) from aqueous solution. The prediction of theoretical breakthrough profiles using Bohart and Adams sorption model was employed to achieve characteristic parameters such as depth of exchange zone, time required for exchange zone to move vertically, moving rate for the exchange zone and adsorption capacity useful for fixed-bed column reactor was investigated under varying operating conditions. The effects of bed depth and flow rate on iron(II) adsorption were studied. Our finding revealed that the Brick from Bangui Region (in Central African Republic), coated with ferrihydrite was a very efficient media for the removal of Fe(II) ions from water. The experimental data showed that the depth and the moving rate (10.3 ± 0.6 cm) and (0.208 ± 0.006 cm/min) respectively of the exchange zone (adsorption zone) were independent of variability of the height of the adsorbent bed column, however the variations of the flow rate affect the moving rate of the exchange zone. The bed depth service time (BDST) model was used and permitted us to predict the service times of columns operated at various flow rates and bed depths and these predicted values were compared with the experimental values.展开更多
A new fi ber optic sensor based on the oxidation of 2,4-dichlorophenol（DCP） catalyzed by iron（II） phthalocyanine（Fe（II）Pc） was developed for the determination of DCP. The optical oxygen sensing fi lm containin...A new fi ber optic sensor based on the oxidation of 2,4-dichlorophenol（DCP） catalyzed by iron（II） phthalocyanine（Fe（II）Pc） was developed for the determination of DCP. The optical oxygen sensing fi lm containing fl uorescence indicator Ru（bpy）3Cl2 was used to detect the consumption of oxygen in solution. Moreover, a lock-in amplifier was used to determine the lifetime of the sensor head by detecting its phase delay change. The results reveal that the sensor has a linear detection range of 1.0×10^-6- 9.0×10^-5 mol/L and a response time of 5 min. The sensor also has high selectivity, good repeatability and stability. It can be used effectively to determine DCP concentration in real samples.展开更多
Some problems including low treatment capacity,agglomeration and clogging phenomena,and short working life,limit the application of pre-treatment methods involving zero-valent iron （ZVI）.In this article,ZVI was froz...Some problems including low treatment capacity,agglomeration and clogging phenomena,and short working life,limit the application of pre-treatment methods involving zero-valent iron （ZVI）.In this article,ZVI was frozen in an amorphous state through a melt-spinning technique,and the decolorization effect of amorphous ZVI on Acid Orange II solution was investigated under varied conditions of experimental variables such as reaction temperature,ribbon dosage,and initial pH.Batch experiments suggested that the decolorization rate was enhanced with the increase of reaction temperature and ribbon dosage,but decreased with increasing initial solution pH.Kinetic analyses indicated that the decolorization process followed a first order exponential kinetic model,and the surface-normalized decolorization rate could reach 2.09 L/（m^2 ·min） at room temperature,which was about ten times larger than any previously reported under similar conditions.Recycling experiments also proved that the ribbons could be reused at least four times without obvious decay of decolorization rate and efficiency.This study suggests a tremendous application potential for amorphous ZVI in remediation of groundwater or wastewater contaminated with azo dyes.展开更多
Iron tetranitrosyl complex bearing the thiosulfate ligand (TNIC) is an efficient nitrogen monoxide donor (NO). He shows antitumor properties and may be used as an original drug for the therapy of acute coronary syndro...Iron tetranitrosyl complex bearing the thiosulfate ligand (TNIC) is an efficient nitrogen monoxide donor (NO). He shows antitumor properties and may be used as an original drug for the therapy of acute coronary syndrome. In this work, the reaction of the TNIC with adenosine triphosphoric acid (ATP) was studied. Formation of the products for the reaction of ATP with TNIC was shown by electronic microscopy. The kinetics of the reaction was controlled by spectrofluorometric method, and the complexation constant was measured. The mechanism of interaction of ATP with TNIC was proposed, and the relevant kinetic model satisfactorily described the experimental data, which permitted to calculate the rate constants for these process stages. NMR, IR, and M?ssbauer studies were used for determination of the reaction product structure. NMR study showed TNIC interaction only with adenine part of ATP. The method of IR spectroscopy identified both the absence NO in the reaction products and the occurrence of new Fe-S and Fe-N bonds. M?ssbauer study showed that iron in the reaction products was presented by two forms: Fe(II) and Fe(III). Thus, the structures for the [ATP-Fe2+S] and [ATP-Fe3+S] complexes were proposed.展开更多
[Objectives]This study aimed to optimize the chelation process for complex microelement iron supplement derived from pig blood by response surface methodology.[Methods]On the basis of single-factor test,p H value,conc...[Objectives]This study aimed to optimize the chelation process for complex microelement iron supplement derived from pig blood by response surface methodology.[Methods]On the basis of single-factor test,p H value,concentration of polypeptide solution and volume ratio of polypeptide solution to FeCl_2 solution were selected as influencing factors with Fe(II)chelation rate as the indicator for Box-Behnken central composite experimental design with three factors and three levels.The effects of three factors on the response value were analyzed by response surface methodology.[Results]The optimized chelation process for complex microelement iron supplement derived from pig blood by response surface methodology was as follows:pH 5.40,polypeptide solution concentration 2.27%,volume ratio of polypeptide solution to FeCl_2 solution 2.16∶1.Under this condition,the predictive Fe(II)chelation rate of iron supplement was 79.37%,while the actual value was 79.41%.[Conclusions]The optimized process may provide new thoughts for the development and utilization of complex microelement iron supplement derived from pig blood.展开更多
Plasma iron is normally bound to the iron transport protein transferrin, but there are some iron ions not associated with transferrin. The latter ions are generally termed as non-transferrin-bound iron (NTBI) or labil...Plasma iron is normally bound to the iron transport protein transferrin, but there are some iron ions not associated with transferrin. The latter ions are generally termed as non-transferrin-bound iron (NTBI) or labile plasma iron. The NTBI has been thought to play an important role in iron-induced cell damage with resultant peroxidation of cell membrane lipids and other biomolecules, and such oxidative damage is implicated as an important contributor in the pathogenesis of cancer, cardiovascular disease, aging and other degenerative disorders, but little is understood about the chemical composition of NTBI and the origin of toxicity due to NTBI. In this review, we demonstrated the several chemical models for NTBI, and elucidated the chemical mechanism of iron toxicity due to NTBI in human body on the basis of my concept on the mechanism of oxygen activation in biological oxygenases. This has lead to the conclusion that 1) NTBI are divided into two groups, water-in-soluble and water-soluble ones, 2) some of the water-soluble NTBI react with oxygen or hydrogen peroxide, changing these molecules to those exhibiting the reactivity similar to singlet oxygen (1△g), and this is the main reason for NTBI to induce the oxidative stress, and 3) the responsibility of hydroxyl radical or free singlet oxygen is negligible as a “reactive oxygen species” in the human body. Based on the discussions described in this article we have proposed a new technique to prevent the oxidative damage due to NTBI. In order to achieve the purpose, we have synthesized the new superpolyphenols which contain more than 100 molecules of catechol derivative in one polymeric compound;these are sometimes water-insoluble, and in another cases, water-soluble. We have observed that some of these compounds can eliminate NTBI effectively from the plasma, and also some of these derivatives can remove hydrogen peroxide from the solution. Thus, we can hope that our new super-polyphenols should depress greatly the oxidative stress due to NTBI, which may be consistent with the facts that the Japanese tea catechins which contain polyphenols exhibit high preventing effects against lifestyle-related diseases, and that some polyphenols have been known to protect the pathogenesis of Alzheimer’s disease. We also discussed the antioxidative function by zinc(II) ion, which depresses the oxidative damage by NTBI by promoting the formation of iron deposition.展开更多
文摘Fixed-bed operating experimental column conditions were studied to evaluate the performance of brick from Bangui Region (in Central African Republic), coated with iron oxyhydroxide (ferrihydrite) for the removal of iron(II) from aqueous solution. The prediction of theoretical breakthrough profiles using Bohart and Adams sorption model was employed to achieve characteristic parameters such as depth of exchange zone, time required for exchange zone to move vertically, moving rate for the exchange zone and adsorption capacity useful for fixed-bed column reactor was investigated under varying operating conditions. The effects of bed depth and flow rate on iron(II) adsorption were studied. Our finding revealed that the Brick from Bangui Region (in Central African Republic), coated with ferrihydrite was a very efficient media for the removal of Fe(II) ions from water. The experimental data showed that the depth and the moving rate (10.3 ± 0.6 cm) and (0.208 ± 0.006 cm/min) respectively of the exchange zone (adsorption zone) were independent of variability of the height of the adsorbent bed column, however the variations of the flow rate affect the moving rate of the exchange zone. The bed depth service time (BDST) model was used and permitted us to predict the service times of columns operated at various flow rates and bed depths and these predicted values were compared with the experimental values.
基金Funded by the National Natural Science Foundation of China(Nos.61377092 and 51303115)
文摘A new fi ber optic sensor based on the oxidation of 2,4-dichlorophenol（DCP） catalyzed by iron（II） phthalocyanine（Fe（II）Pc） was developed for the determination of DCP. The optical oxygen sensing fi lm containing fl uorescence indicator Ru（bpy）3Cl2 was used to detect the consumption of oxygen in solution. Moreover, a lock-in amplifier was used to determine the lifetime of the sensor head by detecting its phase delay change. The results reveal that the sensor has a linear detection range of 1.0×10^-6- 9.0×10^-5 mol/L and a response time of 5 min. The sensor also has high selectivity, good repeatability and stability. It can be used effectively to determine DCP concentration in real samples.
基金the financial support from the Ministry of Science and Technology of China(No. 2011CB606301)the National Natural Science Foundation of China (No. 50825402,51101156)
文摘Some problems including low treatment capacity,agglomeration and clogging phenomena,and short working life,limit the application of pre-treatment methods involving zero-valent iron （ZVI）.In this article,ZVI was frozen in an amorphous state through a melt-spinning technique,and the decolorization effect of amorphous ZVI on Acid Orange II solution was investigated under varied conditions of experimental variables such as reaction temperature,ribbon dosage,and initial pH.Batch experiments suggested that the decolorization rate was enhanced with the increase of reaction temperature and ribbon dosage,but decreased with increasing initial solution pH.Kinetic analyses indicated that the decolorization process followed a first order exponential kinetic model,and the surface-normalized decolorization rate could reach 2.09 L/（m^2 ·min） at room temperature,which was about ten times larger than any previously reported under similar conditions.Recycling experiments also proved that the ribbons could be reused at least four times without obvious decay of decolorization rate and efficiency.This study suggests a tremendous application potential for amorphous ZVI in remediation of groundwater or wastewater contaminated with azo dyes.
文摘Iron tetranitrosyl complex bearing the thiosulfate ligand (TNIC) is an efficient nitrogen monoxide donor (NO). He shows antitumor properties and may be used as an original drug for the therapy of acute coronary syndrome. In this work, the reaction of the TNIC with adenosine triphosphoric acid (ATP) was studied. Formation of the products for the reaction of ATP with TNIC was shown by electronic microscopy. The kinetics of the reaction was controlled by spectrofluorometric method, and the complexation constant was measured. The mechanism of interaction of ATP with TNIC was proposed, and the relevant kinetic model satisfactorily described the experimental data, which permitted to calculate the rate constants for these process stages. NMR, IR, and M?ssbauer studies were used for determination of the reaction product structure. NMR study showed TNIC interaction only with adenine part of ATP. The method of IR spectroscopy identified both the absence NO in the reaction products and the occurrence of new Fe-S and Fe-N bonds. M?ssbauer study showed that iron in the reaction products was presented by two forms: Fe(II) and Fe(III). Thus, the structures for the [ATP-Fe2+S] and [ATP-Fe3+S] complexes were proposed.
基金Supported by Youth Fund of National Natural Science Foundation of China(31801673)Talent Development Fund of Anhui Academy of Agricultural Sciences(17F1205)+2 种基金Youth Innovation Fund of President of Anhui Academy of Agricultural Sciences(17B1220)Team Building Project of Anhui Academy of Agricultural Sciences(18C1225)Youth Fund of Natural Science Foundation of Anhui Province(1808085QC94)
文摘[Objectives]This study aimed to optimize the chelation process for complex microelement iron supplement derived from pig blood by response surface methodology.[Methods]On the basis of single-factor test,p H value,concentration of polypeptide solution and volume ratio of polypeptide solution to FeCl_2 solution were selected as influencing factors with Fe(II)chelation rate as the indicator for Box-Behnken central composite experimental design with three factors and three levels.The effects of three factors on the response value were analyzed by response surface methodology.[Results]The optimized chelation process for complex microelement iron supplement derived from pig blood by response surface methodology was as follows:pH 5.40,polypeptide solution concentration 2.27%,volume ratio of polypeptide solution to FeCl_2 solution 2.16∶1.Under this condition,the predictive Fe(II)chelation rate of iron supplement was 79.37%,while the actual value was 79.41%.[Conclusions]The optimized process may provide new thoughts for the development and utilization of complex microelement iron supplement derived from pig blood.
文摘Plasma iron is normally bound to the iron transport protein transferrin, but there are some iron ions not associated with transferrin. The latter ions are generally termed as non-transferrin-bound iron (NTBI) or labile plasma iron. The NTBI has been thought to play an important role in iron-induced cell damage with resultant peroxidation of cell membrane lipids and other biomolecules, and such oxidative damage is implicated as an important contributor in the pathogenesis of cancer, cardiovascular disease, aging and other degenerative disorders, but little is understood about the chemical composition of NTBI and the origin of toxicity due to NTBI. In this review, we demonstrated the several chemical models for NTBI, and elucidated the chemical mechanism of iron toxicity due to NTBI in human body on the basis of my concept on the mechanism of oxygen activation in biological oxygenases. This has lead to the conclusion that 1) NTBI are divided into two groups, water-in-soluble and water-soluble ones, 2) some of the water-soluble NTBI react with oxygen or hydrogen peroxide, changing these molecules to those exhibiting the reactivity similar to singlet oxygen (1△g), and this is the main reason for NTBI to induce the oxidative stress, and 3) the responsibility of hydroxyl radical or free singlet oxygen is negligible as a “reactive oxygen species” in the human body. Based on the discussions described in this article we have proposed a new technique to prevent the oxidative damage due to NTBI. In order to achieve the purpose, we have synthesized the new superpolyphenols which contain more than 100 molecules of catechol derivative in one polymeric compound;these are sometimes water-insoluble, and in another cases, water-soluble. We have observed that some of these compounds can eliminate NTBI effectively from the plasma, and also some of these derivatives can remove hydrogen peroxide from the solution. Thus, we can hope that our new super-polyphenols should depress greatly the oxidative stress due to NTBI, which may be consistent with the facts that the Japanese tea catechins which contain polyphenols exhibit high preventing effects against lifestyle-related diseases, and that some polyphenols have been known to protect the pathogenesis of Alzheimer’s disease. We also discussed the antioxidative function by zinc(II) ion, which depresses the oxidative damage by NTBI by promoting the formation of iron deposition.
