Objective:To investigate the relation between fruit seeds,plants residuals and appendicitis. Methods:Among cases that underwent appendectomy,the appendicitis cases having fruit seeds and undigested plant residuals in ...Objective:To investigate the relation between fruit seeds,plants residuals and appendicitis. Methods:Among cases that underwent appendectomy,the appendicitis cases having fruit seeds and undigested plant residuals in their etiology were examined retrospectively.Also, histopathological features,age,sex,and parameters of morbidity and mortality were used. Results:Fruit seed was found in one case(0.05%) with presence of pus in appendix lumen, undigested plant residuals in 7 cases(0.35%).It was determined that there were appendix inflammation in 2 of the plant residuals cases,while there were obstruction and lymphoid hyperplasia in the appendix lumen of 5 cases.No mortality was observed.Conclusions:The ratio of acute appendicitis caused by plants is minimal among all appendectomised patients, but avoidence of eating undigested fruit seeds and chewing plants well may help to prevent appendicitis.展开更多
Objective:To evaluate the potency of carboxymethyl chitosan-2,2' ethylenedioxy bisethylamine-folate(CMC-EDBE-FA) on tissue injury,antioxidant status and glutathione system in tissue mitochondria and serum against ...Objective:To evaluate the potency of carboxymethyl chitosan-2,2' ethylenedioxy bisethylamine-folate(CMC-EDBE-FA) on tissue injury,antioxidant status and glutathione system in tissue mitochondria and serum against nicotine-induced oxidative stress in mice.Methods: CMC-EDBE-FA was prepared on basis of carboxymethyl chitosan tagged with folic acid by covalently linkage through 2,2' ethylenedioxy bis-ethylamine.Animals were divided into four groups,i.e.,control,nicotine(1 mg/kg bw/day),CMC-EDBE-FA(1 mg/kg bw/day) and nicotine(1 mg/kg bw/day) and CMC-EDBE-FA(1 mg/kg bw/day) for 7 days.Levels of lipid peroxidation, oxidized glutathione level,antioxidant enzyme status and DNA damage were observed and compared.Results:The significantly increase of lipid peroxidation,oxidized glutathione levels and DNA damage was observed in nicotine treated group as compared with control group;those were significantly reduced in CMC-EDBE-FA supplemented group.Moreover,significantly reduced antioxidant status in nicotine treated group was effectively ameliorated by the supplementation of CMC-EDBE-FA.Only CMC-EDBE-FA treated groups showed no significant change as compared with control group;rather than it repairs the tissue damage of nicotine treated group.Conclusions:These findings suggest that CMC-EDBE-FA is non-toxic and ameliorates nicotine-induced toxicity.展开更多
Low temperature catalysts are attracting increasing attention in the selective catalytic reduction(SCR)of NO with NH3.Mn Ox-decorated Mg Al layered double oxide(Mn/Mg Al-LDO)was synthesized via a facile fast pour assi...Low temperature catalysts are attracting increasing attention in the selective catalytic reduction(SCR)of NO with NH3.Mn Ox-decorated Mg Al layered double oxide(Mn/Mg Al-LDO)was synthesized via a facile fast pour assisted co-precipitation(FP-CP)process.Compared to the Mn/Mg Al-LDO obtained via slow drop assisted coprecipitation(SD-CP)method,the Mn/Mg Al-LDO(FP-CP)has excellent activity.The Mn/Mg Al-LDO(FP-CP)catalyst was shown to possess a high NO conversion rate of 76%-100%from 25 to 150℃,which is much better than the control Mn/Mg Al-LDO(SD-CP)(29.4%-75.8%).In addition,the Mn/Mg Al-LDO(FP-CP)offered an enhanced NO conversion rate of 97%and a N2selectivity of 97.3%at 100℃;the NO conversion rate was 100%and the N2selectivity was 90%at 150℃with a GHSV of 60,000 h^-1.The Mn/Mg Al-LDO(FP-CP)catalyst exhibited a smaller fragment nano-sheet structure(sheet thickness of 7.23 nm).An apparent lattice disorder was observed in the HRTEM image confirming the presence of many defects.The H2-TPR curves show that the Mn/Mg Al-LDO(FP-CP)catalyst has abundant reducing substances.Furthermore,the enhanced surface acidity makes the NH3concentration of the Mn/Mg Al-LDO(FP-CP)catalyst lower than 100 ml·m^-3after the reaction from 25 to 400℃.This can effectively reduce the ammonia escape rate in the SCR reaction.Thus,the Mn/Mg Al-LDO(FP-CP)catalyst has potential applications in stationary industrial installations for environmentally friendly ultra-low temperature SCR.展开更多
Safe, sustainable, and green production of hydro gen peroxide is an exciting proposition due to the role of hydrogen peroxide as a green oxidant and energy carrier for fuel cells. The current work reports the developm...Safe, sustainable, and green production of hydro gen peroxide is an exciting proposition due to the role of hydrogen peroxide as a green oxidant and energy carrier for fuel cells. The current work reports the development of carbon dot-impregnated waterborne hyperbranched polyurethane as a heterogeneous photo-catalyst for solar-driven production of hydrogen peroxide. The results reveal that the carbon dots possess a suitable band-gap of 2.98 eV,which facilitates effective splitting of both water and ethanol under solar irradiation. Inclusion of the carbon dots within the eco-friendly polymeric material ensures their catalytic activity and also provides a facile route for easy catalyst separation, especially from a solubilizing medium.The overall process was performed in accordance with the principles of green chemistry using bio-based precursorsand aqueous medium. This work highlights the potential of carbon dots as an effective photo-catalyst.展开更多
Nanostructured ZnO and CuO, and coupled oxides, i.e., ZnCu, Zn2Cu, and ZnCu2, with ZnO:CuO molar ratios of 1:1, 2:1, and 1:2, respectively, were successfully prepared through a simple, one-step, microwave-assisted ure...Nanostructured ZnO and CuO, and coupled oxides, i.e., ZnCu, Zn2Cu, and ZnCu2, with ZnO:CuO molar ratios of 1:1, 2:1, and 1:2, respectively, were successfully prepared through a simple, one-step, microwave-assisted urea–nitrate combustion synthesis, without the use of organic solvents or surfactants. The prepared samples were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis, transmission electron microscopy, Fourier-transform infrared spectroscopy, diffuse reflectance spectroscopy, and photoluminescence spectroscopy. The optical absorption of Zn O extended into the visible region after CuO loading. The photocatalytic activities of ZnO, CuO, and the coupled oxides were evaluated based on photodegradation of 2,4-dichlorophenol under visible-light irradiation. The coupled metal oxide Zn2Cu showed the best photocatalytic activity; this was mainly attributed to the extended photoresponsive range and the increased charge separation rate in the nanocomposite. The photocatalytic degradation process obeyed pseudo-first-order kinetics. The results suggest that the coupled metal oxide Zn2Cu has potential applications as an efficient catalytic material with high efficiency and recyclability for the photocatalytic degradation of organic pollutants in aqueous solution under visible-light irradiation.展开更多
Plasma treatment can be used to modify the structure of natural fibre like jute fora variety of applications. Environmentally friendly jute fibre was treated with argon and oxygenplasma. The treated samples were chara...Plasma treatment can be used to modify the structure of natural fibre like jute fora variety of applications. Environmentally friendly jute fibre was treated with argon and oxygenplasma. The treated samples were characterized by X-ray diffraction (XRD), Fourier transforminfrared spectroscopy (FTIR) and optical microscope. The macromolecular and microstructuralchanges in cellulose confirmed the change by plasma treatment. The XRD results confirmed thatthe crystal size and the crystallinity of the plasma treated fibre increased. Argon plasma treatedfibre had a smooth and compact surface, compared to oxygen plasma treated fibre. The maximumstain (i.e. stress) concentrated in the oxygen plasma treated fibre. Optical micrographs showedthe oxygen plasma treated fibre tended to rupture due to higher strain (i.e., stress) comparedto fibre with argon plasma treatment. FTIR results also provided the evidence of change in thechemical constituents with plasma treatment.展开更多
The vertically aligned one-dimensional(1 D)core-shell structure can maximize the exposure and use of the functionally active surface while maintaining the geometric effects caused by the underlying structure.Herein,we...The vertically aligned one-dimensional(1 D)core-shell structure can maximize the exposure and use of the functionally active surface while maintaining the geometric effects caused by the underlying structure.Herein,we have fabricated 1 D vertically aligned ZnO/V2O5 core-shell hetero-nanostructure nanorod arrays(NRs)for photoelectrochemical(PEC)water splitting.ZnO/V2O5 NRs were prepared through the hydrothermal growing of ZnO NRs and then radio frequency(RF)magnetron sputtering deposition of V2O5 for 300,600 and 900 s.The photocurrent density of ZnO/V2O5-based photoanodes was gradually increased with the sputtering time,reaching the maximum value of 1.21 m A/cm^2 at 1.23 V vs.reversible hydrogen electrode(RHE)for ZnO/V2O5-600,whereas for pure ZnO-based photoanode was 0.42 mA/cm^2.The incident photon to electron conversion efficiency(IPCE)of ZnO/V2O5-600 evaluated to be 82.3%which was 2.3 times higher than that of ZnO(36.4%).The improved PEC performance of ZnO/V2O5-600 is because the core-shell structure with a moderate thickness of the V2O5 layer has the extremely high carrier density,largest electrochemically active surface area(ECSA),largest carrier density,lowest charge recombination rate,and the longest lifetime of e-h pairs due to the formation of the staggered gap junction.This study provides an effective way to design and fabrication of hetero-nanostructures for highefficiency photoelectrodes.展开更多
In this study,we reported on the concept and practical use of cation exchange resin(CER)for removing anions in water via pretreating the CER with metal salts.The cation exchange resinsupported iron and magnesium oxide...In this study,we reported on the concept and practical use of cation exchange resin(CER)for removing anions in water via pretreating the CER with metal salts.The cation exchange resinsupported iron and magnesium oxides/hydroxides composite(FeMg/CER)was synthesized and introduced as a new and potential adsorbent for selective removal of nitrate ion in the water environment.Characteristics of FeMg/CER were determined by techniques such as Fouriertransform infrared spectroscopy,scanning electron microscopy,and Xray diffraction.The results showed that FeMg/CER material had a high nitrate adsorption capacity of 200 mg NO_(3)^()·g^(1)with a fast equilibrium adsorption time of 30 min at pH 5.In addition,it had good durability of at least 10 times of regeneration,which could be applied to practical water and wastewater treatment.展开更多
Various nanosized zinc aluminate(ZnAl2O4) samples were prepared by a conventional and a mi- crowave method both with and without using Opuntia dilenii haw plant extract,and were charac- terized by X-ray diffraction(XR...Various nanosized zinc aluminate(ZnAl2O4) samples were prepared by a conventional and a mi- crowave method both with and without using Opuntia dilenii haw plant extract,and were charac- terized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),high resolution scanning electron microscopy(HRSEM),energy dispersion scanning(EDX),temperature dependent conductance measurements, thermoelectric power measurements, ultraviolet-visible (UV-Vis) diffuse reflectance spectroscopy,and photoluminescence spectroscopy.The formation of a pure ZnAl2O4 phase was confirmed by XRD and FT-IR.A change in morphology from nanosized plates to nanosized sheets with,respectively,the conventional and microwave heating methods was clearly shown by HRSEM.UV-Vis diffusion reflectance spectroscopy measured the band gaps of ZnAl2O4 nanosized plates and nanosized sheets as 3.5 and 3.9 eV,respectively.The synthesized ZnAl2O4 was single crystalline and has three photoluminescence emissions at 482,528,and 540 nm.ZnAl2O4 nanosized sheets prepared by the microwave method showed higher catalytic activity for the oxida- tion of benzyl alcohol(85% conversion) than ZnAl2O4 nanosized plates prepared by the convention- al method(60% conversion).展开更多
Objective:To evaluate the acute toxicity of carboxymethyl chitosan-2,2' ethylenedioxy bisethylamine-folate(CMC-EDBE-FA) and as well as possible effect on microbial growth and in vitro cell cyto-toxicity.Methods:CM...Objective:To evaluate the acute toxicity of carboxymethyl chitosan-2,2' ethylenedioxy bisethylamine-folate(CMC-EDBE-FA) and as well as possible effect on microbial growth and in vitro cell cyto-toxicity.Methods:CMC-EDBE-FA was prepared on basis of carboxymethyl chitosan tagged with folic acid by covalently linkage through 2,2' elhylenedioxy bis-ethylamine. In vivo acute toxicity,in vitro cyto-toxicity and antimicrobial activity of CMC-EDBE-FA nanoparticle were determined.Results:Vancomycin exhibited the antibacterial activity against vancomycin sensitive Staphylococcus aureus,but CMC-EDBE-FA nanoparticle did not give any antibacterial activity as evidenced by minimal inhibitory concentration(MIC),minimal bactericidal concentration(MBC),disc agar diffusion(DAD) and killing kinetic assay.Further,the CMC-EDBE-FA nanoparticle showed no signs of in vivo acute toxicity up to a dose level of 1000 mg/kg p.o.,and as well as in vitro cyto-toxicity up to 230 μg/mL.Conclnsions:These findings suggest that CMC-EDBE-FA nanoparticle is expected to be safe for biomedical applications.展开更多
The mechanical and physical properties of biodegradable magnesium(Mg)alloys make them suitable for temporary orthopaedic implants.The success of these alloys depends on their performance in the physiological environme...The mechanical and physical properties of biodegradable magnesium(Mg)alloys make them suitable for temporary orthopaedic implants.The success of these alloys depends on their performance in the physiological environment.In the present work,surface modification of Mg-Ca binary alloy by acid pickling for better biomineralization and controlled biodegradation is explored.The corrosion rates of nitric and phosphoric acid treated samples were analysed by conducting electrochemical corrosion tests.In vitro degradation behaviour was studied using immersion test in simulated body fluid(SBF).The sample surfaces were characterized using scanning electron microscope(SEM),energy dispersive X-ray spectroscopy(EDS),Fourier transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS).It is seen that acid pickling leads to significant improvement in biomineralization and develop in situ calcium phosphate(Ca P)coating on the sample surfaces.In addition,the treated samples recorded a reduced degradation rate in the SBF compared to untreated samples.Thus,acid pickling is suggested as an effective surface treatment method to tailor the biomineralization and degradation behaviour of the Mg-Ca alloy in the physiological environment.展开更多
The nanocomposite of polypyrrole (PPy) and carboxylated multi-walled carbon nanotubes (MWCNT) was synthesized by in situ chemical oxidative polymerization method using HCl as a dopant and Ammonium persulphate (APS) as...The nanocomposite of polypyrrole (PPy) and carboxylated multi-walled carbon nanotubes (MWCNT) was synthesized by in situ chemical oxidative polymerization method using HCl as a dopant and Ammonium persulphate (APS) as an oxidant. The MWCNTs were carboxylic functionalized and were ultrasonicated to obtain uniform dispersion within the PPy matrix. Surface morphology of nanocomposites was investigated by Field Emission Scanning Electron microscopy (FE-SEM) and revealed that the functionalized MWCNTs were well embedded. X-Ray diffraction (XRD), Fourier Transform Infrared (FT-IR) Spectroscopy, Raman spectroscopy and UV-Vis spectroscopy were used to characterize the synthesized PPy-MWCNT nanocomposite. It was found that in situ polymerized PPy layer matrix was formed on carboxylated MWCNT and there was uniform dispersion of MWCNTs within the PPy matrix with significant interaction between PPy and MWCNTs. The response of the prepared PPy-MWCNT nanocomposite sensors was studied in the form of sensitivity towards Ammonia gas (NH3). The synergistic effects of the PPy-coated MWCNTs improve the gas sensing properties. Results showed that the sensitivity increased with NH3 concentration and it was also affected by the MWCNT content in PPy matrix. Furthermore, the sensor in pellet form reported here is robust, cost effective and relatively stable at room temperature.展开更多
基金Supported by the Department of Biotechnology.Government of India
文摘Objective:To investigate the relation between fruit seeds,plants residuals and appendicitis. Methods:Among cases that underwent appendectomy,the appendicitis cases having fruit seeds and undigested plant residuals in their etiology were examined retrospectively.Also, histopathological features,age,sex,and parameters of morbidity and mortality were used. Results:Fruit seed was found in one case(0.05%) with presence of pus in appendix lumen, undigested plant residuals in 7 cases(0.35%).It was determined that there were appendix inflammation in 2 of the plant residuals cases,while there were obstruction and lymphoid hyperplasia in the appendix lumen of 5 cases.No mortality was observed.Conclusions:The ratio of acute appendicitis caused by plants is minimal among all appendectomised patients, but avoidence of eating undigested fruit seeds and chewing plants well may help to prevent appendicitis.
文摘Objective:To evaluate the potency of carboxymethyl chitosan-2,2' ethylenedioxy bisethylamine-folate(CMC-EDBE-FA) on tissue injury,antioxidant status and glutathione system in tissue mitochondria and serum against nicotine-induced oxidative stress in mice.Methods: CMC-EDBE-FA was prepared on basis of carboxymethyl chitosan tagged with folic acid by covalently linkage through 2,2' ethylenedioxy bis-ethylamine.Animals were divided into four groups,i.e.,control,nicotine(1 mg/kg bw/day),CMC-EDBE-FA(1 mg/kg bw/day) and nicotine(1 mg/kg bw/day) and CMC-EDBE-FA(1 mg/kg bw/day) for 7 days.Levels of lipid peroxidation, oxidized glutathione level,antioxidant enzyme status and DNA damage were observed and compared.Results:The significantly increase of lipid peroxidation,oxidized glutathione levels and DNA damage was observed in nicotine treated group as compared with control group;those were significantly reduced in CMC-EDBE-FA supplemented group.Moreover,significantly reduced antioxidant status in nicotine treated group was effectively ameliorated by the supplementation of CMC-EDBE-FA.Only CMC-EDBE-FA treated groups showed no significant change as compared with control group;rather than it repairs the tissue damage of nicotine treated group.Conclusions:These findings suggest that CMC-EDBE-FA is non-toxic and ameliorates nicotine-induced toxicity.
基金supported by Science and Technology Innovation Talents Program of Bingtuan(No.2019CB025)Major Scientific and Technological Project of Bingtuan(No.2018AA002)。
文摘Low temperature catalysts are attracting increasing attention in the selective catalytic reduction(SCR)of NO with NH3.Mn Ox-decorated Mg Al layered double oxide(Mn/Mg Al-LDO)was synthesized via a facile fast pour assisted co-precipitation(FP-CP)process.Compared to the Mn/Mg Al-LDO obtained via slow drop assisted coprecipitation(SD-CP)method,the Mn/Mg Al-LDO(FP-CP)has excellent activity.The Mn/Mg Al-LDO(FP-CP)catalyst was shown to possess a high NO conversion rate of 76%-100%from 25 to 150℃,which is much better than the control Mn/Mg Al-LDO(SD-CP)(29.4%-75.8%).In addition,the Mn/Mg Al-LDO(FP-CP)offered an enhanced NO conversion rate of 97%and a N2selectivity of 97.3%at 100℃;the NO conversion rate was 100%and the N2selectivity was 90%at 150℃with a GHSV of 60,000 h^-1.The Mn/Mg Al-LDO(FP-CP)catalyst exhibited a smaller fragment nano-sheet structure(sheet thickness of 7.23 nm).An apparent lattice disorder was observed in the HRTEM image confirming the presence of many defects.The H2-TPR curves show that the Mn/Mg Al-LDO(FP-CP)catalyst has abundant reducing substances.Furthermore,the enhanced surface acidity makes the NH3concentration of the Mn/Mg Al-LDO(FP-CP)catalyst lower than 100 ml·m^-3after the reaction from 25 to 400℃.This can effectively reduce the ammonia escape rate in the SCR reaction.Thus,the Mn/Mg Al-LDO(FP-CP)catalyst has potential applications in stationary industrial installations for environmentally friendly ultra-low temperature SCR.
基金DBT(Grant No.BT/235/NE/TBP/2011 Dated April 30,2012),India,for financial support
文摘Safe, sustainable, and green production of hydro gen peroxide is an exciting proposition due to the role of hydrogen peroxide as a green oxidant and energy carrier for fuel cells. The current work reports the development of carbon dot-impregnated waterborne hyperbranched polyurethane as a heterogeneous photo-catalyst for solar-driven production of hydrogen peroxide. The results reveal that the carbon dots possess a suitable band-gap of 2.98 eV,which facilitates effective splitting of both water and ethanol under solar irradiation. Inclusion of the carbon dots within the eco-friendly polymeric material ensures their catalytic activity and also provides a facile route for easy catalyst separation, especially from a solubilizing medium.The overall process was performed in accordance with the principles of green chemistry using bio-based precursorsand aqueous medium. This work highlights the potential of carbon dots as an effective photo-catalyst.
文摘Nanostructured ZnO and CuO, and coupled oxides, i.e., ZnCu, Zn2Cu, and ZnCu2, with ZnO:CuO molar ratios of 1:1, 2:1, and 1:2, respectively, were successfully prepared through a simple, one-step, microwave-assisted urea–nitrate combustion synthesis, without the use of organic solvents or surfactants. The prepared samples were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis, transmission electron microscopy, Fourier-transform infrared spectroscopy, diffuse reflectance spectroscopy, and photoluminescence spectroscopy. The optical absorption of Zn O extended into the visible region after CuO loading. The photocatalytic activities of ZnO, CuO, and the coupled oxides were evaluated based on photodegradation of 2,4-dichlorophenol under visible-light irradiation. The coupled metal oxide Zn2Cu showed the best photocatalytic activity; this was mainly attributed to the extended photoresponsive range and the increased charge separation rate in the nanocomposite. The photocatalytic degradation process obeyed pseudo-first-order kinetics. The results suggest that the coupled metal oxide Zn2Cu has potential applications as an efficient catalytic material with high efficiency and recyclability for the photocatalytic degradation of organic pollutants in aqueous solution under visible-light irradiation.
基金support provided by Department of Science and Technology,New Delhiall India Council for Technical Education,New Delhi for the work presented in this paper
文摘Plasma treatment can be used to modify the structure of natural fibre like jute fora variety of applications. Environmentally friendly jute fibre was treated with argon and oxygenplasma. The treated samples were characterized by X-ray diffraction (XRD), Fourier transforminfrared spectroscopy (FTIR) and optical microscope. The macromolecular and microstructuralchanges in cellulose confirmed the change by plasma treatment. The XRD results confirmed thatthe crystal size and the crystallinity of the plasma treated fibre increased. Argon plasma treatedfibre had a smooth and compact surface, compared to oxygen plasma treated fibre. The maximumstain (i.e. stress) concentrated in the oxygen plasma treated fibre. Optical micrographs showedthe oxygen plasma treated fibre tended to rupture due to higher strain (i.e., stress) comparedto fibre with argon plasma treatment. FTIR results also provided the evidence of change in thechemical constituents with plasma treatment.
基金supported by National Research Foundation(NRF)of Korean grant funded by the Korea government(MSIP)(Grant number:2017R1E1A1A01074550)。
文摘The vertically aligned one-dimensional(1 D)core-shell structure can maximize the exposure and use of the functionally active surface while maintaining the geometric effects caused by the underlying structure.Herein,we have fabricated 1 D vertically aligned ZnO/V2O5 core-shell hetero-nanostructure nanorod arrays(NRs)for photoelectrochemical(PEC)water splitting.ZnO/V2O5 NRs were prepared through the hydrothermal growing of ZnO NRs and then radio frequency(RF)magnetron sputtering deposition of V2O5 for 300,600 and 900 s.The photocurrent density of ZnO/V2O5-based photoanodes was gradually increased with the sputtering time,reaching the maximum value of 1.21 m A/cm^2 at 1.23 V vs.reversible hydrogen electrode(RHE)for ZnO/V2O5-600,whereas for pure ZnO-based photoanode was 0.42 mA/cm^2.The incident photon to electron conversion efficiency(IPCE)of ZnO/V2O5-600 evaluated to be 82.3%which was 2.3 times higher than that of ZnO(36.4%).The improved PEC performance of ZnO/V2O5-600 is because the core-shell structure with a moderate thickness of the V2O5 layer has the extremely high carrier density,largest electrochemically active surface area(ECSA),largest carrier density,lowest charge recombination rate,and the longest lifetime of e-h pairs due to the formation of the staggered gap junction.This study provides an effective way to design and fabrication of hetero-nanostructures for highefficiency photoelectrodes.
基金Vietnam National University-Ho Chi Minh City under grant number A2020-16-01.
文摘In this study,we reported on the concept and practical use of cation exchange resin(CER)for removing anions in water via pretreating the CER with metal salts.The cation exchange resinsupported iron and magnesium oxides/hydroxides composite(FeMg/CER)was synthesized and introduced as a new and potential adsorbent for selective removal of nitrate ion in the water environment.Characteristics of FeMg/CER were determined by techniques such as Fouriertransform infrared spectroscopy,scanning electron microscopy,and Xray diffraction.The results showed that FeMg/CER material had a high nitrate adsorption capacity of 200 mg NO_(3)^()·g^(1)with a fast equilibrium adsorption time of 30 min at pH 5.In addition,it had good durability of at least 10 times of regeneration,which could be applied to practical water and wastewater treatment.
文摘Various nanosized zinc aluminate(ZnAl2O4) samples were prepared by a conventional and a mi- crowave method both with and without using Opuntia dilenii haw plant extract,and were charac- terized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),high resolution scanning electron microscopy(HRSEM),energy dispersion scanning(EDX),temperature dependent conductance measurements, thermoelectric power measurements, ultraviolet-visible (UV-Vis) diffuse reflectance spectroscopy,and photoluminescence spectroscopy.The formation of a pure ZnAl2O4 phase was confirmed by XRD and FT-IR.A change in morphology from nanosized plates to nanosized sheets with,respectively,the conventional and microwave heating methods was clearly shown by HRSEM.UV-Vis diffusion reflectance spectroscopy measured the band gaps of ZnAl2O4 nanosized plates and nanosized sheets as 3.5 and 3.9 eV,respectively.The synthesized ZnAl2O4 was single crystalline and has three photoluminescence emissions at 482,528,and 540 nm.ZnAl2O4 nanosized sheets prepared by the microwave method showed higher catalytic activity for the oxida- tion of benzyl alcohol(85% conversion) than ZnAl2O4 nanosized plates prepared by the convention- al method(60% conversion).
基金financially supported by Department of Biotechnology,Government of India(grant No.BT/PR10861/NNT/28/131/2008)
文摘Objective:To evaluate the acute toxicity of carboxymethyl chitosan-2,2' ethylenedioxy bisethylamine-folate(CMC-EDBE-FA) and as well as possible effect on microbial growth and in vitro cell cyto-toxicity.Methods:CMC-EDBE-FA was prepared on basis of carboxymethyl chitosan tagged with folic acid by covalently linkage through 2,2' elhylenedioxy bis-ethylamine. In vivo acute toxicity,in vitro cyto-toxicity and antimicrobial activity of CMC-EDBE-FA nanoparticle were determined.Results:Vancomycin exhibited the antibacterial activity against vancomycin sensitive Staphylococcus aureus,but CMC-EDBE-FA nanoparticle did not give any antibacterial activity as evidenced by minimal inhibitory concentration(MIC),minimal bactericidal concentration(MBC),disc agar diffusion(DAD) and killing kinetic assay.Further,the CMC-EDBE-FA nanoparticle showed no signs of in vivo acute toxicity up to a dose level of 1000 mg/kg p.o.,and as well as in vitro cyto-toxicity up to 230 μg/mL.Conclnsions:These findings suggest that CMC-EDBE-FA nanoparticle is expected to be safe for biomedical applications.
基金financial grant No.5/4–5/3ORTHO/2019-NCD-I Dt.16–09–2019 from Indian Council of Medical Research(ICMR)the grant from DST-FIST-No.SR/FST/ETI-388/2015,Govt.of India used for setting up 3D Profilometer facility at NIT Calicut。
文摘The mechanical and physical properties of biodegradable magnesium(Mg)alloys make them suitable for temporary orthopaedic implants.The success of these alloys depends on their performance in the physiological environment.In the present work,surface modification of Mg-Ca binary alloy by acid pickling for better biomineralization and controlled biodegradation is explored.The corrosion rates of nitric and phosphoric acid treated samples were analysed by conducting electrochemical corrosion tests.In vitro degradation behaviour was studied using immersion test in simulated body fluid(SBF).The sample surfaces were characterized using scanning electron microscope(SEM),energy dispersive X-ray spectroscopy(EDS),Fourier transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS).It is seen that acid pickling leads to significant improvement in biomineralization and develop in situ calcium phosphate(Ca P)coating on the sample surfaces.In addition,the treated samples recorded a reduced degradation rate in the SBF compared to untreated samples.Thus,acid pickling is suggested as an effective surface treatment method to tailor the biomineralization and degradation behaviour of the Mg-Ca alloy in the physiological environment.
文摘The nanocomposite of polypyrrole (PPy) and carboxylated multi-walled carbon nanotubes (MWCNT) was synthesized by in situ chemical oxidative polymerization method using HCl as a dopant and Ammonium persulphate (APS) as an oxidant. The MWCNTs were carboxylic functionalized and were ultrasonicated to obtain uniform dispersion within the PPy matrix. Surface morphology of nanocomposites was investigated by Field Emission Scanning Electron microscopy (FE-SEM) and revealed that the functionalized MWCNTs were well embedded. X-Ray diffraction (XRD), Fourier Transform Infrared (FT-IR) Spectroscopy, Raman spectroscopy and UV-Vis spectroscopy were used to characterize the synthesized PPy-MWCNT nanocomposite. It was found that in situ polymerized PPy layer matrix was formed on carboxylated MWCNT and there was uniform dispersion of MWCNTs within the PPy matrix with significant interaction between PPy and MWCNTs. The response of the prepared PPy-MWCNT nanocomposite sensors was studied in the form of sensitivity towards Ammonia gas (NH3). The synergistic effects of the PPy-coated MWCNTs improve the gas sensing properties. Results showed that the sensitivity increased with NH3 concentration and it was also affected by the MWCNT content in PPy matrix. Furthermore, the sensor in pellet form reported here is robust, cost effective and relatively stable at room temperature.
