This work investigated the removal, kinetics and thermodynamics of iron(II) ions (Fe(II)) by adsorption in static and dynamic conditions in aqueous media on activated carbons (AC-i30min, AC-i1h, and AC-i24h), prepared...This work investigated the removal, kinetics and thermodynamics of iron(II) ions (Fe(II)) by adsorption in static and dynamic conditions in aqueous media on activated carbons (AC-i30min, AC-i1h, and AC-i24h), prepared from palm nut shells collected in the city of Franceville to Gabon, using potassium hydroxide (KOH) as the activating agent. Results on the elimination of Fe(II) in static and dynamic adsorption on prepared activated carbons (ACs) showed that the AC-i24h adsorbent has the best Fe(II) adsorption capacities at saturation (Qsat). The Qsat obtained on AC-i24h in static and dynamic conditions (17.87 and 10.38 mg/g, respectively) were higher than those of AC-i30min (13.89 and 5.54 mg/g respectively) and AC-i1h (14.92 and 8.64 mg/g respectively). Moreover, the static adsorption was more effective in the removal of Fe(II) ions in aqueous media in our experimental conditions. The percentage removal (%E) of Fe(II) obtained on prepared activated carbons in static conditions was better than those obtained in dynamic conditions, especially on AC-i24h, where the %E was 89.27% in static and 61.56% in dynamic. In kinetics, results showed that the pseudo-second-order kinetic model best described the adsorption mechanisms of Fe(II) on prepared activated carbons in static adsorption, with mainly of chemisorption on the solid surfaces. However, in dynamic conditions, the pseudo-first-order kinetic model was more suitable. In addition to the weak interactions between Fe(II) and the activated carbon surfaces, strong interactions (chemisorption) were also observed. Also, thermodynamic data obtained on AC-i24h in static adsorption indicated that the adsorption of Fe(II) was spontaneous and increased with temperature (ΔG˚ H˚ = 503.54 KJ/mol).展开更多
The novel Fe-N co-doped ordered mesoporous carbon with high catalytic activity in m-cresol removal was prepared by urea-assisted impregnation and simple pyrolysis method.During the preparation of the Fe-NC catalyst,th...The novel Fe-N co-doped ordered mesoporous carbon with high catalytic activity in m-cresol removal was prepared by urea-assisted impregnation and simple pyrolysis method.During the preparation of the Fe-NC catalyst,the complexation of N elements in urea could anchor Fe,and the formation of C3N4during urea pyrolysis could also prevent migration and aggregation of Fe species,which jointly improve the dispersion and stability of Fe.The FeN4sites and highly dispersed Fe nanoparticles synergistically trigger the dual-site peroxymonosulfate (PMS) activation for highly efficient m-cresol degradation,while the ordered mesoporous structure of the catalyst could improve the mass transfer rate of the catalytic process,which together promote catalytic degradation of m-cresol by PMS activation.Reactive oxygen species (ROS) analytic experiments demonstrate that the system degrades m-cresol by free radical pathway mainly based on SO_(4)^(-)·and·OH,and partially based on·OH as the active components,and a possible PMS activation mechanism by 5Fe-50 for m-cresol degradation was proposed.This study can provide theoretical guidance for the preparation of efficient and stable catalysts for the degradation of organic pollutants by activated PMS.展开更多
Three types of paddy soils, derived from granite, Quaternary red clay andbasalt, respectively, were selected to study the effects of Fe and Mn in paddy soils on methaneproduction and emission through pot and incubatio...Three types of paddy soils, derived from granite, Quaternary red clay andbasalt, respectively, were selected to study the effects of Fe and Mn in paddy soils on methaneproduction and emission through pot and incubation experiments. The results indicated that thedifference of Fe and Mn in paddy soils was one of the important factors causing obvious differencesin methane emission from different soil types. Soil Fe and Mn affecting methane emission from thepaddy soils was likely through affectingsoil Eh and forming Fe and Mn plagues on rice roots.Different rates and valences of added Fe and Mn significantly affected methane production from paddysoils. Therefore, this study enhanced understanding of processes controlling methane emission frompaddy soils and may help to improve modeling and estimating regional and global methane emissionfrom paddy soils.展开更多
To effectively solve the agglomeration problems in the solid state reaction process,pre-adding glucose is adopted to the synthesis of Li Fe PO4/C energy materials using Fe–P waste slag. The average particle grain siz...To effectively solve the agglomeration problems in the solid state reaction process,pre-adding glucose is adopted to the synthesis of Li Fe PO4/C energy materials using Fe–P waste slag. The average particle grain size of Li FeP O4/C decreases,and the impurities in Li Fe PO4/C composites reduce to a great extent. It makes great sense to the mass industrial production. The optimum synthesis conditions determined in this work are based on the orthogonal experiments. The samples synthesized in a scale of 500 g exhibit high purity,excellent electrochemical performance,high reaction activity,good reversibility,and low polarization level.The discharge capacities are 145,134,117,and 102 m Ah/g at the current densities of 0.1 C,0.2 C,0.5 C and1 C,respectively. This work puts forward a practical suggestion for mass producing environmental benign and low cost Li FeP O4/C as cathode materials of lithium ion batteries.展开更多
Erectile dysfunction （ED） is a major complication of diabetes mellitus. Icariin has been shown to enhance erectile function through its bioactive form, icarisid Ih This study investigates the effects of icarisid Ⅱ ...Erectile dysfunction （ED） is a major complication of diabetes mellitus. Icariin has been shown to enhance erectile function through its bioactive form, icarisid Ih This study investigates the effects of icarisid Ⅱ on diabetic rats with ED and its potential mechanism viathe assessment of advanced glycosylation end products （AGEs）, autophagy, mTOR and the NO-cGMP pathway. Icarisid Ⅱ was extracted from icariin by an enzymatic method. In the control and diabetic ED groups, rats were administered normal saline; in the icarisid Ⅱ group, rats were administered icarisid Ⅱ intragastrically. Erectile function was evaluated by measuring intracavernosal pressure/mean arterial pressure （ICP/MAP）. AGE concentrations, nitric oxide synthase （NOS） activity and cGMP concentration were assessed by enzyme immunoassay. Cell proliferation was analysed using methyl thiazolyl tetrazolium assay and flow cytometry. Autophagosomes were observed by transmission electron microscopy, monodansylcadaverine staining and GFP-LC3 Iocalisation. The expression of NOS isoforms and key proteins in autophagy were examined by western blot. Our results have shown that Icarisid Ⅱ increased ICP/MAP values, the smooth muscle cell （SMC） growth curve, S phase and SMC/collagen fibril （SMC/CF） proportions and decreased Beclin 1 （P〈0.05）. Icarisid Ⅱ significantly increased the proliferative index and p-p70S6K（Thr389） levels and decreased the numbers of autophagosomes and the levels of LC3-11 （P〈0.01）. Icarisid Ⅱ decreased AGE concentrations and increased cGMP concentration, NOS activity （P〈0.05） and cNOS levels （P〈0.01） in the diabetic ED group. Therefore, Icarisid Ⅱ constitutes a promising compound for diabetic ED and might be involved in the upregulation of SMC proliferation and the NO-cGMP pathway and the downregulation of AGEs, autophagy and the mTOR pathway.展开更多
Magnetically modified Fe-Al pillared bentonite（Fe3O4/ Fe-Al-Bent） was prepared via chemical co-precipitation method and characterized by powder X-ray diffraction（XRD）, Brunauer-EmmettTeller（BET）, Fourier transfo...Magnetically modified Fe-Al pillared bentonite（Fe3O4/ Fe-Al-Bent） was prepared via chemical co-precipitation method and characterized by powder X-ray diffraction（XRD）, Brunauer-EmmettTeller（BET）, Fourier transform infrared spectroscopy（FTIR） and scanning electron microscopy（SEM）. A series of experiments were carried out to investigate the degradation of Orange II by the obtained heterogeneous catalysts in the presence of H2O2. The experimental result indicated that the synthetic materials had a high catalytic activity and good reusability.展开更多
Catalytic oxidation of benzene with N_(2)O to phenol over the hierarchical and microporous Fe/ZSM-5-based catalysts in a continuous fixedbed reactor was investigated.The spent catalyst was in-situ regenerated by an ox...Catalytic oxidation of benzene with N_(2)O to phenol over the hierarchical and microporous Fe/ZSM-5-based catalysts in a continuous fixedbed reactor was investigated.The spent catalyst was in-situ regenerated by an oxidative treatment using N_(2)O and in total 10 reaction-regeneration cycles were performed.A 100% N_(2)O conversion,93.3% phenol selectivity,and high initial phenol formation rate of 16.49±0.06mmol_(phenol gcatalyst)^(-1)h^(-1)at time on stream(TOS) of 5 min,and a good phenol productivity of 147.06 mmol_(phenol gcatalyst)^(-1)during catalyst lifetime of 1800 min were obtained on a fresh hierarchical Fe/ZSM-5-Hi2.8 catalyst.With the reaction-regeneration cycle,N_(2)O conversion is fully recovered within TOS of 3 h,moreover,the phenol productivity was decreased ca.2.2±0.8% after each cycle,leading to a total phenol productivity of ca.0.44 ton_(pheol kg_(catalyst)^(-1)estimated for 300 cycles.Catalyst characterizations imply that the coke is rapidly deposited on catalyst surface in the initial TOS of 3 h(0.28 mgc_(gcatalyst)^(-1)min^(-1)) and gradually becomes graphitic during the TOS of 30 h with a slow formation rate of 0.06 mgc g_(catalyst)^(-1)min^(-1).Among others(e.g.,the decrease of textural property and acidity),the nearly complete coverage of the active Fe-O-Al sites by coke accounts for the main catalyst deactivation.Besides these reversible deactivation characteristics related to coking,the irreversible catalyst deactivation is also observed with the reaction-regeneration cycle.The latter is reflected by a further decreased amount of the active Fe-O-Al sites,which agglomerate on catalyst surface with the cycle,likely associated with the hard coke residue that is not completely removed by the regeneration.展开更多
The synthesis is and crystal structure are reported for the sheet-like compourd [CU2(oxpn)Fe(CN )5(NO)]. there oxpn is the dianion of M, M'-bis(3-aminopropyl)oxamide. This compound crustallizes in the orthogonal s...The synthesis is and crystal structure are reported for the sheet-like compourd [CU2(oxpn)Fe(CN )5(NO)]. there oxpn is the dianion of M, M'-bis(3-aminopropyl)oxamide. This compound crustallizes in the orthogonal space group Puma. with a=11 .413(4), b=22.242(5), c=7.736(2) A, and Z=4.The structure was refined to conventionat discrepancy factors R=0.047 and Pw=0.054. The Cu(II ) and Fe(III)centers are bridged by oxpn and cyanide, the formal behaves as a his-terdentate tigand bound to cooper(II)ion to form (II) dimers. whereas the latter bridges Cu(II) and Fe(III) centers in both symmetric and asymetric end- to-end bis-monodentate fashions, spreading out along be plane to form a 20 network. The Structure is made up of CuFe unit with Cu(II) and Fe(III) ions locating in a distorted square-based pyramid and a compressed octahedron, respectively.展开更多
An integrated production planning and control model based on MRPⅡand JIT is put forward through analyzing the characteristics of magnetic materials manufacturing companies. Master Production Schedule with limited cap...An integrated production planning and control model based on MRPⅡand JIT is put forward through analyzing the characteristics of magnetic materials manufacturing companies. Master Production Schedule with limited capacity and operational plan in workshop level based on the basic data of flow chart are formulated by this model which applied JIT idea and based on customer order demand. Push production is adapted during execution phase combined with process flow cards. The model is helpful to reduce inventory,keep certain flexbility of production and improve continuity and equilibrium of manufacturing process.展开更多
文摘This work investigated the removal, kinetics and thermodynamics of iron(II) ions (Fe(II)) by adsorption in static and dynamic conditions in aqueous media on activated carbons (AC-i30min, AC-i1h, and AC-i24h), prepared from palm nut shells collected in the city of Franceville to Gabon, using potassium hydroxide (KOH) as the activating agent. Results on the elimination of Fe(II) in static and dynamic adsorption on prepared activated carbons (ACs) showed that the AC-i24h adsorbent has the best Fe(II) adsorption capacities at saturation (Qsat). The Qsat obtained on AC-i24h in static and dynamic conditions (17.87 and 10.38 mg/g, respectively) were higher than those of AC-i30min (13.89 and 5.54 mg/g respectively) and AC-i1h (14.92 and 8.64 mg/g respectively). Moreover, the static adsorption was more effective in the removal of Fe(II) ions in aqueous media in our experimental conditions. The percentage removal (%E) of Fe(II) obtained on prepared activated carbons in static conditions was better than those obtained in dynamic conditions, especially on AC-i24h, where the %E was 89.27% in static and 61.56% in dynamic. In kinetics, results showed that the pseudo-second-order kinetic model best described the adsorption mechanisms of Fe(II) on prepared activated carbons in static adsorption, with mainly of chemisorption on the solid surfaces. However, in dynamic conditions, the pseudo-first-order kinetic model was more suitable. In addition to the weak interactions between Fe(II) and the activated carbon surfaces, strong interactions (chemisorption) were also observed. Also, thermodynamic data obtained on AC-i24h in static adsorption indicated that the adsorption of Fe(II) was spontaneous and increased with temperature (ΔG˚ H˚ = 503.54 KJ/mol).
基金gratefully acknowledge the financial support of the National Natural Science Foundation of China(22108145 and 21978143)the Shandong Province Natural Science Foundation(ZR2020QB189)+1 种基金State Key Laboratory of Heavy Oil Processing(SKLHOP202203008)the Talent Foundation funded by Province and Ministry Co-construction Collaborative Innovation Center of Eco-chemical Engineering(STHGYX2201).
文摘The novel Fe-N co-doped ordered mesoporous carbon with high catalytic activity in m-cresol removal was prepared by urea-assisted impregnation and simple pyrolysis method.During the preparation of the Fe-NC catalyst,the complexation of N elements in urea could anchor Fe,and the formation of C3N4during urea pyrolysis could also prevent migration and aggregation of Fe species,which jointly improve the dispersion and stability of Fe.The FeN4sites and highly dispersed Fe nanoparticles synergistically trigger the dual-site peroxymonosulfate (PMS) activation for highly efficient m-cresol degradation,while the ordered mesoporous structure of the catalyst could improve the mass transfer rate of the catalytic process,which together promote catalytic degradation of m-cresol by PMS activation.Reactive oxygen species (ROS) analytic experiments demonstrate that the system degrades m-cresol by free radical pathway mainly based on SO_(4)^(-)·and·OH,and partially based on·OH as the active components,and a possible PMS activation mechanism by 5Fe-50 for m-cresol degradation was proposed.This study can provide theoretical guidance for the preparation of efficient and stable catalysts for the degradation of organic pollutants by activated PMS.
基金Project supported by the State Science and Technology Commission of China.
文摘Three types of paddy soils, derived from granite, Quaternary red clay andbasalt, respectively, were selected to study the effects of Fe and Mn in paddy soils on methaneproduction and emission through pot and incubation experiments. The results indicated that thedifference of Fe and Mn in paddy soils was one of the important factors causing obvious differencesin methane emission from different soil types. Soil Fe and Mn affecting methane emission from thepaddy soils was likely through affectingsoil Eh and forming Fe and Mn plagues on rice roots.Different rates and valences of added Fe and Mn significantly affected methane production from paddysoils. Therefore, this study enhanced understanding of processes controlling methane emission frompaddy soils and may help to improve modeling and estimating regional and global methane emissionfrom paddy soils.
基金supported by the National Science Foundation of China(grant no.21206099)
文摘To effectively solve the agglomeration problems in the solid state reaction process,pre-adding glucose is adopted to the synthesis of Li Fe PO4/C energy materials using Fe–P waste slag. The average particle grain size of Li FeP O4/C decreases,and the impurities in Li Fe PO4/C composites reduce to a great extent. It makes great sense to the mass industrial production. The optimum synthesis conditions determined in this work are based on the orthogonal experiments. The samples synthesized in a scale of 500 g exhibit high purity,excellent electrochemical performance,high reaction activity,good reversibility,and low polarization level.The discharge capacities are 145,134,117,and 102 m Ah/g at the current densities of 0.1 C,0.2 C,0.5 C and1 C,respectively. This work puts forward a practical suggestion for mass producing environmental benign and low cost Li FeP O4/C as cathode materials of lithium ion batteries.
文摘Erectile dysfunction （ED） is a major complication of diabetes mellitus. Icariin has been shown to enhance erectile function through its bioactive form, icarisid Ih This study investigates the effects of icarisid Ⅱ on diabetic rats with ED and its potential mechanism viathe assessment of advanced glycosylation end products （AGEs）, autophagy, mTOR and the NO-cGMP pathway. Icarisid Ⅱ was extracted from icariin by an enzymatic method. In the control and diabetic ED groups, rats were administered normal saline; in the icarisid Ⅱ group, rats were administered icarisid Ⅱ intragastrically. Erectile function was evaluated by measuring intracavernosal pressure/mean arterial pressure （ICP/MAP）. AGE concentrations, nitric oxide synthase （NOS） activity and cGMP concentration were assessed by enzyme immunoassay. Cell proliferation was analysed using methyl thiazolyl tetrazolium assay and flow cytometry. Autophagosomes were observed by transmission electron microscopy, monodansylcadaverine staining and GFP-LC3 Iocalisation. The expression of NOS isoforms and key proteins in autophagy were examined by western blot. Our results have shown that Icarisid Ⅱ increased ICP/MAP values, the smooth muscle cell （SMC） growth curve, S phase and SMC/collagen fibril （SMC/CF） proportions and decreased Beclin 1 （P〈0.05）. Icarisid Ⅱ significantly increased the proliferative index and p-p70S6K（Thr389） levels and decreased the numbers of autophagosomes and the levels of LC3-11 （P〈0.01）. Icarisid Ⅱ decreased AGE concentrations and increased cGMP concentration, NOS activity （P〈0.05） and cNOS levels （P〈0.01） in the diabetic ED group. Therefore, Icarisid Ⅱ constitutes a promising compound for diabetic ED and might be involved in the upregulation of SMC proliferation and the NO-cGMP pathway and the downregulation of AGEs, autophagy and the mTOR pathway.
基金Funded by the Specialized Research Fund for the Doctoral Program of Higher Education of China(20114219110002)the Natural Science Foundation of Hubei Province(Nos.2014CFB810&2014CFB812)
文摘Magnetically modified Fe-Al pillared bentonite（Fe3O4/ Fe-Al-Bent） was prepared via chemical co-precipitation method and characterized by powder X-ray diffraction（XRD）, Brunauer-EmmettTeller（BET）, Fourier transform infrared spectroscopy（FTIR） and scanning electron microscopy（SEM）. A series of experiments were carried out to investigate the degradation of Orange II by the obtained heterogeneous catalysts in the presence of H2O2. The experimental result indicated that the synthetic materials had a high catalytic activity and good reusability.
基金Financial support by the Specialized Research Fund for Doctoral Program of Higher Education,China (No.20120010110003)。
文摘Catalytic oxidation of benzene with N_(2)O to phenol over the hierarchical and microporous Fe/ZSM-5-based catalysts in a continuous fixedbed reactor was investigated.The spent catalyst was in-situ regenerated by an oxidative treatment using N_(2)O and in total 10 reaction-regeneration cycles were performed.A 100% N_(2)O conversion,93.3% phenol selectivity,and high initial phenol formation rate of 16.49±0.06mmol_(phenol gcatalyst)^(-1)h^(-1)at time on stream(TOS) of 5 min,and a good phenol productivity of 147.06 mmol_(phenol gcatalyst)^(-1)during catalyst lifetime of 1800 min were obtained on a fresh hierarchical Fe/ZSM-5-Hi2.8 catalyst.With the reaction-regeneration cycle,N_(2)O conversion is fully recovered within TOS of 3 h,moreover,the phenol productivity was decreased ca.2.2±0.8% after each cycle,leading to a total phenol productivity of ca.0.44 ton_(pheol kg_(catalyst)^(-1)estimated for 300 cycles.Catalyst characterizations imply that the coke is rapidly deposited on catalyst surface in the initial TOS of 3 h(0.28 mgc_(gcatalyst)^(-1)min^(-1)) and gradually becomes graphitic during the TOS of 30 h with a slow formation rate of 0.06 mgc g_(catalyst)^(-1)min^(-1).Among others(e.g.,the decrease of textural property and acidity),the nearly complete coverage of the active Fe-O-Al sites by coke accounts for the main catalyst deactivation.Besides these reversible deactivation characteristics related to coking,the irreversible catalyst deactivation is also observed with the reaction-regeneration cycle.The latter is reflected by a further decreased amount of the active Fe-O-Al sites,which agglomerate on catalyst surface with the cycle,likely associated with the hard coke residue that is not completely removed by the regeneration.
文摘The synthesis is and crystal structure are reported for the sheet-like compourd [CU2(oxpn)Fe(CN )5(NO)]. there oxpn is the dianion of M, M'-bis(3-aminopropyl)oxamide. This compound crustallizes in the orthogonal space group Puma. with a=11 .413(4), b=22.242(5), c=7.736(2) A, and Z=4.The structure was refined to conventionat discrepancy factors R=0.047 and Pw=0.054. The Cu(II ) and Fe(III)centers are bridged by oxpn and cyanide, the formal behaves as a his-terdentate tigand bound to cooper(II)ion to form (II) dimers. whereas the latter bridges Cu(II) and Fe(III) centers in both symmetric and asymetric end- to-end bis-monodentate fashions, spreading out along be plane to form a 20 network. The Structure is made up of CuFe unit with Cu(II) and Fe(III) ions locating in a distorted square-based pyramid and a compressed octahedron, respectively.
基金supported by Ministry of Education Social Science and Humanities Fund(12YJA630187)SHANNXI Social Science Fund(10Q067)High Education Research Fund of Northwestern Polytechnical University(2014)
文摘An integrated production planning and control model based on MRPⅡand JIT is put forward through analyzing the characteristics of magnetic materials manufacturing companies. Master Production Schedule with limited capacity and operational plan in workshop level based on the basic data of flow chart are formulated by this model which applied JIT idea and based on customer order demand. Push production is adapted during execution phase combined with process flow cards. The model is helpful to reduce inventory,keep certain flexbility of production and improve continuity and equilibrium of manufacturing process.
