Acute lung injury(ALI)is a critical respiratory disorder with a high mortality rate and is caused by several factors.Addressing oxidative stress and infiammation is a pivotal strategy for ALI treatment.In this study,w...Acute lung injury(ALI)is a critical respiratory disorder with a high mortality rate and is caused by several factors.Addressing oxidative stress and infiammation is a pivotal strategy for ALI treatment.In this study,we introduced a novel nanotherapeutic approach involving a curcumin-loaded ceria nanoenzyme delivery system tailored to counteract the multifaceted aspects of ALI.This system leverages the individual and combined effects of the components to provide a comprehensive therapeutic solution.The dual-action capability of this nanosystem was manifested by mitigating mitochondrial oxidative stress in lung epithelial cells and inhibiting the transient receptor potential melanosome-associated protein 2(TRPM2)-NOD-like receptor thermal protein domain associated protein 3(NLRP3)signaling pathway,offering a highly effective therapeutic approach to ALI.Our findings reveal the underlying mechanisms of this innovative nanodelivery system,showcasing its potential as a versatile strategy for ALI treatment and encouraging further exploration of nanoenzyme-based therapies for ALI.展开更多
Nano cerium oxide films were applied on AA7020-T6 aluminum alloy and the effects of acetic acid concentration on the microstructure and electrochemical properties of the coated samples were investigated by using scann...Nano cerium oxide films were applied on AA7020-T6 aluminum alloy and the effects of acetic acid concentration on the microstructure and electrochemical properties of the coated samples were investigated by using scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and potentiodynamic polarization methods. It has been found that by increasing the acetic acid/CeCl3·7H2O molar ratio, high uniform and crack-free films with well-developed grains were obtained and grain sizes of the films decreased. Elimination of cracks and decreasing grain size of the nano cerium oxide films caused corrosion resistance to increase.展开更多
Ta/NiFe/Ta ultrathin films with and without nano-oxide layers （NOLs） were prepared by magnetron sputtering followed by a vacuum annealing process. The influence of NOLs on the magnetoresistance （MR） ratio of ultra...Ta/NiFe/Ta ultrathin films with and without nano-oxide layers （NOLs） were prepared by magnetron sputtering followed by a vacuum annealing process. The influence of NOLs on the magnetoresistance （MR） ratio of ultrathin permalloy films was studied. The results show that the influence of grain size and textures on the MR ratio becomes weak when the thickness of the NiFe layer is below 15 nm. A higher MR ratio was observed for the thinner （〈 15 nm） NiFe film with NOLs. The MR ratio of a 10 nm NiFe film can be remarkably enhanced by NOLs. The enhanced MR ratio for these ultrathin films can be attributed to the enhanced specular reflection of conduction electrons.展开更多
The different investigation has been carried out on the biological activities of titanium dioxide nanoparticle but the effect of this nano product on the antibacterial activity of different antibiotics has not been ye...The different investigation has been carried out on the biological activities of titanium dioxide nanoparticle but the effect of this nano product on the antibacterial activity of different antibiotics has not been yet demonstrated. In this study the nano size TiO2 is synthesized using citric acid and alpha dextrose and the enhancement effect of TiO2 nanoparticle on the antibacterial activity of different antibiotics was evaluated against Methicillin-resistant Staphylococcus aureus (MRSA). During the present study, different concentrations of nano-scale TiO2 were tested to find out the best concentration that can have the most effective antibacterial property against the MRSA culture. Disk diffusion method was used to determine the antibacterial activity of these antibiotics in the absence and presence of sub inhibitory concentration of TiO2 nano particle. A clinical isolate of MRSA, isolated from Intensive Care Unit (ICU) was used as test strain. In the presence of sub-inhibitory concentration of TiO2 nanoparticle (20 μg/disc) the antibacterial activities of all antibiotics have been increased against test strain with minimum 2 mm to maximum 10mm. The highest increase in inhibitory zone for MRSA was observed against pencillin G and amikacin (each 10 mm). Conversely, in case of nalidixic acid, TiO2 nanoparticle showed a Synergic effect on the antibacterial activity of this antibiotic against test strain. These results signify that the TiO2 nanoparticle potentate the antimicrobial action of beta lactums, cephalosporins, aminoglycosides, glycopeptides, macrolids and lincosamides, tetracycline a possible utilization of nano compound in combination effect against MRSA.展开更多
The adsorptive removal of arsenic by synthetically-prepared nano Fe-Mn binary oxides（FM） was investigated. A novel method using potassium permanganate and ferric chloride as raw materials was used to synthesise FM. ...The adsorptive removal of arsenic by synthetically-prepared nano Fe-Mn binary oxides（FM） was investigated. A novel method using potassium permanganate and ferric chloride as raw materials was used to synthesise FM. The molar ratio of Fe and Mn in the synthetic Fe-Mn binary oxides was 4 ： 3. The FM-1 and FM-2（prepared at different activation temperatures） having high specific surface areas（358.87 and 128.58 m^2/g, respectively） were amorphous and of nano particle types. The amount of arsenic adsorbed on FM-1 was higher than that adsorbed on FM-2 particles. After adsorption by FM-1, residual arsenic concentration decreased to less than 10 μg/L. The adsorption kinetics data were analyzed using different kinetic models including pseudo first-order model, pseudo second-order model, Elovich model and intraparticle diffusion model. Pseudo second-order kinetic model was the most appropriate model to describe the adsorption kinetics. The adsorption percentage of As（Ⅲ） increased in the p H range of 2–3 while it decreased with the increase of pH（ 3〈pH〈10）. The effects of coexisting anions on As（Ⅲ） removal using FM-1 and FM-2 were also studied and the order of the effects is as follows： NO_3^-, Cl-, F-〈SO_4^（2-）, HCO_3-〈H_2PO_4^-, indicating that H_2PO_4^- is the major competitor with As（Ⅲ） for adsorptive sites on the surface of the adsorbents. The higher adsorption capacity of FM-1 makes it potentially attractive adsorbent for the removal of As（Ⅲ） from groundwater.展开更多
As a potential application of titanium-oxide nanoparticles, it is extremely important to investigate a detailed picture of the surface and interior structural properties of nanocrystalline materials, such as rutile an...As a potential application of titanium-oxide nanoparticles, it is extremely important to investigate a detailed picture of the surface and interior structural properties of nanocrystalline materials, such as rutile and anatase with diameters 7.0 and 4.5nm, respectively. X-ray absorption spectroscopy has been used to identify the local Ti environment and related electronic structure. We combine the experimental results at the Ti edge in both bulk and nano-crystals to determine the lattice distortion in terms of differently characteristic preedge features and the variation in the multiple-scattering region of X-ray absorption near-edge structure (XANES) spectra. The relationship between the transition peaks and the surface-to volume ratio is also discussed.展开更多
In this study,the workability of cement-based grouts containing n-TiO 2 nanoparticles and fly ash has been investigated experimentally.Several characteristic quantities(including,but not limited to,the marsh cone flow...In this study,the workability of cement-based grouts containing n-TiO 2 nanoparticles and fly ash has been investigated experimentally.Several characteristic quantities(including,but not limited to,the marsh cone flow time,the mini slump spreading diameter and the plate cohesion meter value)have been measured for different percentages of these additives.The use of fly ash as a mineral additive has been found to result in improvements in terms of workability behavior as expected.Moreover,if nano titanium oxide is also used,an improvement can be obtained regarding the bleeding values for the cement-based grout mixes.Using such experimental data,a multi-layer perceptron artificial neural network model has been developed(5 neurons in the hidden layer of the network model have been developed using a total of 42 experimental data).70%of the data employed in this model have been used for training,15%for validation and 15%for the test phase.The results demonstrate that the artificial neural network model can predict Marsh cone flow time,mini slump spreading diameter and plate cohesion meter values with an average error of 0.15%.展开更多
Nanoscale zero-valent iron （nZVI） assembled on graphene oxide （GO） （rGO-nZVI） composites were synthesized by reduction of GO and ferrous ions with potassium borohydride, for use in Cr（VI） removal from aqueous ...Nanoscale zero-valent iron （nZVI） assembled on graphene oxide （GO） （rGO-nZVI） composites were synthesized by reduction of GO and ferrous ions with potassium borohydride, for use in Cr（VI） removal from aqueous solution. The results showed that the two-dimensional structure of GO could provide a skeleton support for Fe0, thus overcoming the bottleneck of aggregation for nZVI. Also, rGO-nZVI would form a ferric-carbon micro-electrolysis system in Cr（VI）-contaminated aquifers, enhancing and accelerating electron transfer, exhibiting high rate and capacity for Cr（VI） removal. The optimum dosage of the applied rGO-nZVI was linearly correlated with the initial Cr（VI） concentration. Characterization of rGO-nZVI before and after reaction with Cr（VI） revealed the process of Cr（VI） removal： rGO-nZVI firstly transferred electrons from Fe0 cores via their Fe（II）/Fe（III） shells to the GO sheet; there, negatively charged Cr（VI） received electrons and changed into positively charged Cr（III）, which was adsorbed by the negatively charged GO sheet, avoiding the capping and passivating of nZVI rGO-nZVI formed a good electrically conductive network, and thus had long-term electron releasing properties, which was important for groundwater remediation.展开更多
LaNi（0.6）Fe（0.4）O（3-δ） （LNF） powders were synthesized by the glycine-nitrate process and LNF-gadolinium-doped ceria （GDC） nanocomposite cathodes for solid oxide fuel cells （SOFCs） were fabricated by infil...LaNi（0.6）Fe（0.4）O（3-δ） （LNF） powders were synthesized by the glycine-nitrate process and LNF-gadolinium-doped ceria （GDC） nanocomposite cathodes for solid oxide fuel cells （SOFCs） were fabricated by infiltration from LNF porous backbones. Electrochemical properties and Cr-poisoning behavior of LNF-GDC cathodes were studied. Single phase perovskite LNF could be obtained at the glycine to nitrate molar ratio of 1：1. The polarization resistance of the LNF-GDC nanocomposite cathode was significantly decreased in comparison with the LNF. This phenomenon was associated with enhanced catalytic activity and enlarged triple-phase boundary （TPB） length by GDC nano particles. In addition, the nanocomposite cathode showed good Cr tolerance under open circuit condition. The LNF-GDC nanocomposite cathodes were expected for use as a potential cathode in intermediate- temperature solid oxide fuel cells （IT-SOFC）.展开更多
Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability cau...Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability caused by detrimental chlorine chemistry.Herein,we present our recent discovery that the incorporation of Ce into Ni Fe layered double hydroxide nanosheet array on Ni foam(Ce-Ni Fe LDH/NF)emerges as a robust electrocatalyst for seawater oxidation.During the seawater oxidation process,CeO_(2)is generated,effectively repelling Cl^(-)and inhibiting the formation of Cl O-,resulting in a notable enhancement in the oxidation activity and stability of alkaline seawater.The prepared Ce-Ni Fe LDH/NF requires only overpotential of 390 m V to achieve the current density of 1 A cm^(-2),while maintaining long-term stability for 500 h,outperforming the performance of Ni Fe LDH/NF(430 m V,150 h)by a significant margin.This study highlights the effectiveness of a Ce-doping strategy in augmenting the activity and stability of materials based on Ni Fe LDH in seawater electrolysis for oxygen evolution.展开更多
It is normally difficult to prepare nano-sized Ba0.5Sr0.5Co0.8Fe0.2O3-δ（BSCF） oxide at high temperature due to its high surface activity. The complexing process, which has successfully applied in the synthesis of n...It is normally difficult to prepare nano-sized Ba0.5Sr0.5Co0.8Fe0.2O3-δ（BSCF） oxide at high temperature due to its high surface activity. The complexing process, which has successfully applied in the synthesis of nano Sm0.15Ce0.85I1.925 with crystallite size down to 5 nml, just resulted in a coarse BSCF with crystaUite size of 41.9 nm at 900℃. We applied a novel process by simply modifying the solid precursor from the complexing process with concentrated nitric acid treatment. The obtained BSCF powder had a crystaUite size of -25 nm even calcined at 1000℃. The small crystaUite size is extremely promising to enhance the electrochemical performance of cathode for solid oxide fuel cell dramatically.展开更多
A series of nano-size gold catalysts were prepared by deposition-precipitation method using silica material promoted with different amounts of MgO as the carrier. The influences of MgO addition on the structure and pr...A series of nano-size gold catalysts were prepared by deposition-precipitation method using silica material promoted with different amounts of MgO as the carrier. The influences of MgO addition on the structure and property of the nano-size gold catalysts were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, O2 temperature-programmed desorption （O2-TPD）, and inductively coupled with plasma atomic emission spectroscopy （ICP-AES） techniques. The total oxidation of CO was chosen as the probe reaction. The results suggest that for the gold catalysts supported on the silica material after MgO modification, the size of the gold particles is pronouncedly reduced, the oxygen mobility is enhanced, and the catalytic activity for low-temperature CO oxidation is greatly improved. The gold catalyst modified by 6 wt% MgO （Mg/SiO2 weight ratio） shows higher CO oxidation activity, over which the temperature of CO total oxidation is lower about 150 K than that over the silica directly supported gold catalyst.展开更多
The influence of nanostructure on the electrochemical properties of Li-ion battery was investigated. Tin-oxide nanotubes were prepared by combining sol-gel method with polycarbonate template. Scanning electron microsc...The influence of nanostructure on the electrochemical properties of Li-ion battery was investigated. Tin-oxide nanotubes were prepared by combining sol-gel method with polycarbonate template. Scanning electron microscopy and X-ray diffractometry were applied to characterize the obtained material. The electrochemical measurements were conducted on the nanostructured tin-oxides as electrode of Li-ion batteries. The XRD data indicate that the wall of tube is composed of cassiterite crystals of several nanometers. The electrochemical measurements show that the reaction under potential 0.1-0.2 V is possibly related to the tubular structure of the material. It is suggested that the trapping of Li by dangling bonds and defects sites also contributes to the larger irreversible capacity loss in the first discharge.展开更多
In this article, we study modified nano-hydroxyapatite (HAp) by nano manganese oxide (Mn3O4) as adsorbent material to remove iron ions from groundwater. Different parameters were studied to option optimum conditions o...In this article, we study modified nano-hydroxyapatite (HAp) by nano manganese oxide (Mn3O4) as adsorbent material to remove iron ions from groundwater. Different parameters were studied to option optimum conditions of removing such as contact time, pH, initial concentration, a dosage of adsorbent, agitation speed and temperature. Kinetics studies included first order (R2 = 0.915), pseudo-first order (R2 = 0.936), second order (R2 = 0.948), pseudo-second order (R2 = 0.995), Elovich equation model (R2 = 0.977), intraparticle diffusion (R2 = 0.946), Natarajan and Khalaf (R2 = 0.915) were carried out, the obtained results revealed that the pseudo-second order is the best to describe the adsorption process because the correlation coefficient is approaching one (R2 = 0.995). Adsorption isotherm was calculated by using Freundlich, Langmuir and Temkin constants, adsorption capacity from Langmuir model was 0.606 mg/g. Thermodynamic parameters (ΔG, ΔH = ?51 KJ/mol, and ΔS = ?142 (KJ/mol)) for the adsorption process were also calculated and discussed.展开更多
In order to improve the purification properties of polysulfone (PSF) ultrafiltration membranes (UFM), nano-graphene oxide (nano-GO) was taken as modifier, and the physical blending process was adopted in our experimen...In order to improve the purification properties of polysulfone (PSF) ultrafiltration membranes (UFM), nano-graphene oxide (nano-GO) was taken as modifier, and the physical blending process was adopted in our experiment. The microstructure, surface morphology and functional groups of modified UFM have been characterized respectively by scanning electron microscopy, atomic force microscopy and Fourier transform infrared spectroscopy, and the static contact angle between the membrane surface and the water droplet has also been detected to show the change of its hydrophilicity. Through experiments, it has been found that modified UFM has larger and more developed finger micro-pores, and there exist a large number of -OH groups on its surface, and also its hydrophilicity has been enhanced. The result of the experiments show that the modified UFM may keep rejection above 97% and its water flux can be reached at about 219.1 L/(m2·h) under pressure of 1 bar if 0.4 wt% of nano-GO was added. Additionally, the nano-GO can increase the flux recovery radio (FRR) of the membranes, and the maximum FRR was observed as 74.4% if 0.3 wt% of nano-GO was appended.展开更多
Magnetically separable CuO nanoparticles supported on graphene oxide（Fe3O4 NPs/GO-CuO NPs） is synthesized and characterized for the preparation of propargylamines in EtOH,at 90 C.Fe3O4 NPs/GOCuO NPs is found to be a...Magnetically separable CuO nanoparticles supported on graphene oxide（Fe3O4 NPs/GO-CuO NPs） is synthesized and characterized for the preparation of propargylamines in EtOH,at 90 C.Fe3O4 NPs/GOCuO NPs is found to be an efficient catalyst for the A^3-coupling of aldehydes,amines,and alkynes through C-H activation.Both aromatic and aliphatic aldehydes and alkynes are combined with secondary amines to provide a wide range of propargylamines in moderate to excellent yields.展开更多
A kind of new nano composite with ultraviolet （UV） ray resistance and high temperature stability was prepared by in-situ polymerization in low temperature. Polysulfonamide （PSA） was synthesized with 4, 4＇-diamin...A kind of new nano composite with ultraviolet （UV） ray resistance and high temperature stability was prepared by in-situ polymerization in low temperature. Polysulfonamide （PSA） was synthesized with 4, 4＇-diaminodiphenyl sulfone （DDS） and terephthaloyl chloride （TPC） in the common solvent N, N-Dimethyl- -acetamide （DMAc）. Nano filler is a certain nano titanium oxide modified by silicon oxide （TMS）, which plays the role of UV resistance additives. Properties of the novel composite materials were characterized by Atomic Force microscopy （AFM）, thermal gravimetric Analysis （TGA） and Ultraviolet Spectroscopy. AFM had showed the sizes and distributions of TMS particles in the nanocomposite. Ultraviolet Spectroscopy for the nanocomposites showed a large absorption in UV band. TGA showed the decomposition temperature was increased over ten degrees with 0.5% wt TMS for this nanocomposite compared with pure PSA.展开更多
In order to improve optical property of the multi-walled carbon nanotubes(MWNTs),MWNTs were decorated with europium oxide(Eu2O3) nanoparticles by using co-deposition method. The MWNTs/Eu2O3 composites were examined by...In order to improve optical property of the multi-walled carbon nanotubes(MWNTs),MWNTs were decorated with europium oxide(Eu2O3) nanoparticles by using co-deposition method. The MWNTs/Eu2O3 composites were examined by XRD,scanning electron microscopy,transmission electron microscopy,and VUV-Vis Luminescence spectroscopy and citric acid(CA) molecules were introduced onto the surface of MWNTs. The results show that there are many oxygenated functional groups on the surface of the MWNTs after the treatment of mixture acid,such as carboxy,hydroxl,carbony and amidocyanogen. The results of electron microscopy illuminate that the MWNTs are coated by nano-europium oxide after annealed at 750℃. The MWNTs/Eu2O3 composite emits much strong red light at about 610 nm under UV excitation.展开更多
Graphene oxide (GO) is a graphene derivatives that has oxygen-containing functional groups on the graphene basal plane, such as hydroxyl, carbonyl, epoxy and carboxyl groups. GO is considered as a promising material f...Graphene oxide (GO) is a graphene derivatives that has oxygen-containing functional groups on the graphene basal plane, such as hydroxyl, carbonyl, epoxy and carboxyl groups. GO is considered as a promising material for biological applications owing to its excellent surface functionalizability, high specific suface area and good biocompatibility. In this study, GO/chitosan hybrid scaffolds were prepared for tissue engineering. Nano silver was loaded into the scaffold to improve its antibacterial ability and biomimetic Ca-P coatings were deposited on the scaffold surface to enhance its osteoconductivity. First, GO was prepared by the chemical oxidization of graphite. Secondly, nano-Ag loaded GO was prepared by chemical reducing Ag ions in GO solutions. Then, nano-Ag loaded GO solution was mixed with CS solution to form GO-CS gel. Chitosan (CS) and GO were crosslinked by electrostatic interactions between oxygen-containing functional groups of GO and NH2 groups of CS. The gel were freeze dried to produce nano-Ag loaded GO/CS hybrid porous scaffolds. Finally, the as-prepared scaffolds were immersed the into a supersaturated calcium phosphate solution (SCPS) for 7 days to deposite CaP coatings on the surface of the micropores. SEM images showed that nano-Ag uniformly distributed in the scaffold and the CaP covered most of the scaffold surfaces. In vitro cell culture and antimicrobial test indicated the biomimetic mineralized Ag-CS-GO scaffolds have good osteoconductivity and bactericidal ability.展开更多
Organic polymer materials were used as a layer of adhesive into the graphene sheet between the layers to enhance the interaction force between the nano-structure to achieve excellent mechanical properties and barrier ...Organic polymer materials were used as a layer of adhesive into the graphene sheet between the layers to enhance the interaction force between the nano-structure to achieve excellent mechanical properties and barrier properties. PLA with good flowability and easy processing was selected. The mechanical properties and barrier properties of the graphene-based composites were improved by the use of PLA for good flowability, making it easy to enter the GO layer as a binder. Three methods of preparation of GO/PLA homogeneous composite membranes were designed by vacuum filtration. The experimental results show that the injection of PLA as a molecular binder into the GO layer can effectively mimic the nano-structure, and enhance the intergranular force of the graphene molecules and the compatibility with the polymer matrix.展开更多
基金funded by the National Natural Science Foundation of China(Nos.82103885,81871521,82273672)Natural Science Foundation of Shanghai(Nos.21ZR1477700,20ZR1470300)+1 种基金the Shanghai Municipal Health Commission-Outstanding Youth Foundation of Public Health(No.GWV-10.2-YQ48)Sci Tech Funding by CSPFTZ Lingang Special Area Marine Biomedical Innovation Platform。
文摘Acute lung injury(ALI)is a critical respiratory disorder with a high mortality rate and is caused by several factors.Addressing oxidative stress and infiammation is a pivotal strategy for ALI treatment.In this study,we introduced a novel nanotherapeutic approach involving a curcumin-loaded ceria nanoenzyme delivery system tailored to counteract the multifaceted aspects of ALI.This system leverages the individual and combined effects of the components to provide a comprehensive therapeutic solution.The dual-action capability of this nanosystem was manifested by mitigating mitochondrial oxidative stress in lung epithelial cells and inhibiting the transient receptor potential melanosome-associated protein 2(TRPM2)-NOD-like receptor thermal protein domain associated protein 3(NLRP3)signaling pathway,offering a highly effective therapeutic approach to ALI.Our findings reveal the underlying mechanisms of this innovative nanodelivery system,showcasing its potential as a versatile strategy for ALI treatment and encouraging further exploration of nanoenzyme-based therapies for ALI.
文摘Nano cerium oxide films were applied on AA7020-T6 aluminum alloy and the effects of acetic acid concentration on the microstructure and electrochemical properties of the coated samples were investigated by using scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and potentiodynamic polarization methods. It has been found that by increasing the acetic acid/CeCl3·7H2O molar ratio, high uniform and crack-free films with well-developed grains were obtained and grain sizes of the films decreased. Elimination of cracks and decreasing grain size of the nano cerium oxide films caused corrosion resistance to increase.
基金supported by the National Science Foundation of China (Nos.50671008,50871014,and 50831002)
文摘Ta/NiFe/Ta ultrathin films with and without nano-oxide layers （NOLs） were prepared by magnetron sputtering followed by a vacuum annealing process. The influence of NOLs on the magnetoresistance （MR） ratio of ultrathin permalloy films was studied. The results show that the influence of grain size and textures on the MR ratio becomes weak when the thickness of the NiFe layer is below 15 nm. A higher MR ratio was observed for the thinner （〈 15 nm） NiFe film with NOLs. The MR ratio of a 10 nm NiFe film can be remarkably enhanced by NOLs. The enhanced MR ratio for these ultrathin films can be attributed to the enhanced specular reflection of conduction electrons.
文摘The different investigation has been carried out on the biological activities of titanium dioxide nanoparticle but the effect of this nano product on the antibacterial activity of different antibiotics has not been yet demonstrated. In this study the nano size TiO2 is synthesized using citric acid and alpha dextrose and the enhancement effect of TiO2 nanoparticle on the antibacterial activity of different antibiotics was evaluated against Methicillin-resistant Staphylococcus aureus (MRSA). During the present study, different concentrations of nano-scale TiO2 were tested to find out the best concentration that can have the most effective antibacterial property against the MRSA culture. Disk diffusion method was used to determine the antibacterial activity of these antibiotics in the absence and presence of sub inhibitory concentration of TiO2 nano particle. A clinical isolate of MRSA, isolated from Intensive Care Unit (ICU) was used as test strain. In the presence of sub-inhibitory concentration of TiO2 nanoparticle (20 μg/disc) the antibacterial activities of all antibiotics have been increased against test strain with minimum 2 mm to maximum 10mm. The highest increase in inhibitory zone for MRSA was observed against pencillin G and amikacin (each 10 mm). Conversely, in case of nalidixic acid, TiO2 nanoparticle showed a Synergic effect on the antibacterial activity of this antibiotic against test strain. These results signify that the TiO2 nanoparticle potentate the antimicrobial action of beta lactums, cephalosporins, aminoglycosides, glycopeptides, macrolids and lincosamides, tetracycline a possible utilization of nano compound in combination effect against MRSA.
基金supported by the National Natural Science Foundation of China(No.41120124003)the Ministry of Science and Technology of China(No.2012AA062602)the 111 project and Priority Development Projects of SRFDP of the Ministry of Education of China
文摘The adsorptive removal of arsenic by synthetically-prepared nano Fe-Mn binary oxides（FM） was investigated. A novel method using potassium permanganate and ferric chloride as raw materials was used to synthesise FM. The molar ratio of Fe and Mn in the synthetic Fe-Mn binary oxides was 4 ： 3. The FM-1 and FM-2（prepared at different activation temperatures） having high specific surface areas（358.87 and 128.58 m^2/g, respectively） were amorphous and of nano particle types. The amount of arsenic adsorbed on FM-1 was higher than that adsorbed on FM-2 particles. After adsorption by FM-1, residual arsenic concentration decreased to less than 10 μg/L. The adsorption kinetics data were analyzed using different kinetic models including pseudo first-order model, pseudo second-order model, Elovich model and intraparticle diffusion model. Pseudo second-order kinetic model was the most appropriate model to describe the adsorption kinetics. The adsorption percentage of As（Ⅲ） increased in the p H range of 2–3 while it decreased with the increase of pH（ 3〈pH〈10）. The effects of coexisting anions on As（Ⅲ） removal using FM-1 and FM-2 were also studied and the order of the effects is as follows： NO_3^-, Cl-, F-〈SO_4^（2-）, HCO_3-〈H_2PO_4^-, indicating that H_2PO_4^- is the major competitor with As（Ⅲ） for adsorptive sites on the surface of the adsorbents. The higher adsorption capacity of FM-1 makes it potentially attractive adsorbent for the removal of As（Ⅲ） from groundwater.
基金One of us (Z.Y. Wu) was supported by 100-Talent Research Program of The Chinese Academy of Sciences. One of the authors (K. Ibrahim) is grateful to the National Natural Science Foundation of China (NSFC) for financial support (Grant No. 10074063) The
文摘As a potential application of titanium-oxide nanoparticles, it is extremely important to investigate a detailed picture of the surface and interior structural properties of nanocrystalline materials, such as rutile and anatase with diameters 7.0 and 4.5nm, respectively. X-ray absorption spectroscopy has been used to identify the local Ti environment and related electronic structure. We combine the experimental results at the Ti edge in both bulk and nano-crystals to determine the lattice distortion in terms of differently characteristic preedge features and the variation in the multiple-scattering region of X-ray absorption near-edge structure (XANES) spectra. The relationship between the transition peaks and the surface-to volume ratio is also discussed.
基金funded by The Scientific and Technological Research Council of Turkey-TUBITAK[Grant No.219M522].
文摘In this study,the workability of cement-based grouts containing n-TiO 2 nanoparticles and fly ash has been investigated experimentally.Several characteristic quantities(including,but not limited to,the marsh cone flow time,the mini slump spreading diameter and the plate cohesion meter value)have been measured for different percentages of these additives.The use of fly ash as a mineral additive has been found to result in improvements in terms of workability behavior as expected.Moreover,if nano titanium oxide is also used,an improvement can be obtained regarding the bleeding values for the cement-based grout mixes.Using such experimental data,a multi-layer perceptron artificial neural network model has been developed(5 neurons in the hidden layer of the network model have been developed using a total of 42 experimental data).70%of the data employed in this model have been used for training,15%for validation and 15%for the test phase.The results demonstrate that the artificial neural network model can predict Marsh cone flow time,mini slump spreading diameter and plate cohesion meter values with an average error of 0.15%.
基金supported by the National Natural Science Foundation of China(Nos.41772244 and 41530636)
文摘Nanoscale zero-valent iron （nZVI） assembled on graphene oxide （GO） （rGO-nZVI） composites were synthesized by reduction of GO and ferrous ions with potassium borohydride, for use in Cr（VI） removal from aqueous solution. The results showed that the two-dimensional structure of GO could provide a skeleton support for Fe0, thus overcoming the bottleneck of aggregation for nZVI. Also, rGO-nZVI would form a ferric-carbon micro-electrolysis system in Cr（VI）-contaminated aquifers, enhancing and accelerating electron transfer, exhibiting high rate and capacity for Cr（VI） removal. The optimum dosage of the applied rGO-nZVI was linearly correlated with the initial Cr（VI） concentration. Characterization of rGO-nZVI before and after reaction with Cr（VI） revealed the process of Cr（VI） removal： rGO-nZVI firstly transferred electrons from Fe0 cores via their Fe（II）/Fe（III） shells to the GO sheet; there, negatively charged Cr（VI） received electrons and changed into positively charged Cr（III）, which was adsorbed by the negatively charged GO sheet, avoiding the capping and passivating of nZVI rGO-nZVI formed a good electrically conductive network, and thus had long-term electron releasing properties, which was important for groundwater remediation.
基金supported by a grant from the Fundamental R&D Program for Core Technology of Materials (No.10051006)funded by the Ministry of Knowledge Economy, Republic of Koreasupported by the New & Renewable Energy Core Technology Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP), granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea (No. 20113020030050)
文摘LaNi（0.6）Fe（0.4）O（3-δ） （LNF） powders were synthesized by the glycine-nitrate process and LNF-gadolinium-doped ceria （GDC） nanocomposite cathodes for solid oxide fuel cells （SOFCs） were fabricated by infiltration from LNF porous backbones. Electrochemical properties and Cr-poisoning behavior of LNF-GDC cathodes were studied. Single phase perovskite LNF could be obtained at the glycine to nitrate molar ratio of 1：1. The polarization resistance of the LNF-GDC nanocomposite cathode was significantly decreased in comparison with the LNF. This phenomenon was associated with enhanced catalytic activity and enlarged triple-phase boundary （TPB） length by GDC nano particles. In addition, the nanocomposite cathode showed good Cr tolerance under open circuit condition. The LNF-GDC nanocomposite cathodes were expected for use as a potential cathode in intermediate- temperature solid oxide fuel cells （IT-SOFC）.
基金support from the Free Exploration Project of Frontier Technology for Laoshan Laboratory(No.16-02)the National Natural Science Foundation of China(Nos.22072015 and 21927811)。
文摘Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability caused by detrimental chlorine chemistry.Herein,we present our recent discovery that the incorporation of Ce into Ni Fe layered double hydroxide nanosheet array on Ni foam(Ce-Ni Fe LDH/NF)emerges as a robust electrocatalyst for seawater oxidation.During the seawater oxidation process,CeO_(2)is generated,effectively repelling Cl^(-)and inhibiting the formation of Cl O-,resulting in a notable enhancement in the oxidation activity and stability of alkaline seawater.The prepared Ce-Ni Fe LDH/NF requires only overpotential of 390 m V to achieve the current density of 1 A cm^(-2),while maintaining long-term stability for 500 h,outperforming the performance of Ni Fe LDH/NF(430 m V,150 h)by a significant margin.This study highlights the effectiveness of a Ce-doping strategy in augmenting the activity and stability of materials based on Ni Fe LDH in seawater electrolysis for oxygen evolution.
基金This work is also sponsored by the National Basic Research Program of China （No. 2003CB615702）the National Natural Science Foundation of China （No. 20646002, 20576051 and 20436030）+1 种基金Scientific Research Foundation for the Returned 0verseas China Scholars from State Ministry of Education （No. 2004527）Nanjing Ministry of Personnel.
文摘It is normally difficult to prepare nano-sized Ba0.5Sr0.5Co0.8Fe0.2O3-δ（BSCF） oxide at high temperature due to its high surface activity. The complexing process, which has successfully applied in the synthesis of nano Sm0.15Ce0.85I1.925 with crystallite size down to 5 nml, just resulted in a coarse BSCF with crystaUite size of 41.9 nm at 900℃. We applied a novel process by simply modifying the solid precursor from the complexing process with concentrated nitric acid treatment. The obtained BSCF powder had a crystaUite size of -25 nm even calcined at 1000℃. The small crystaUite size is extremely promising to enhance the electrochemical performance of cathode for solid oxide fuel cell dramatically.
基金supported by the Youth Fund Project(2002B25)of Sichuan Department of Educationthe Scientific Research Foundation for Doctor from Yibin College of China(2010B12)
文摘A series of nano-size gold catalysts were prepared by deposition-precipitation method using silica material promoted with different amounts of MgO as the carrier. The influences of MgO addition on the structure and property of the nano-size gold catalysts were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, O2 temperature-programmed desorption （O2-TPD）, and inductively coupled with plasma atomic emission spectroscopy （ICP-AES） techniques. The total oxidation of CO was chosen as the probe reaction. The results suggest that for the gold catalysts supported on the silica material after MgO modification, the size of the gold particles is pronouncedly reduced, the oxygen mobility is enhanced, and the catalytic activity for low-temperature CO oxidation is greatly improved. The gold catalyst modified by 6 wt% MgO （Mg/SiO2 weight ratio） shows higher CO oxidation activity, over which the temperature of CO total oxidation is lower about 150 K than that over the silica directly supported gold catalyst.
基金Project(203630002) supported by the National Natural Science Foundation of China
文摘The influence of nanostructure on the electrochemical properties of Li-ion battery was investigated. Tin-oxide nanotubes were prepared by combining sol-gel method with polycarbonate template. Scanning electron microscopy and X-ray diffractometry were applied to characterize the obtained material. The electrochemical measurements were conducted on the nanostructured tin-oxides as electrode of Li-ion batteries. The XRD data indicate that the wall of tube is composed of cassiterite crystals of several nanometers. The electrochemical measurements show that the reaction under potential 0.1-0.2 V is possibly related to the tubular structure of the material. It is suggested that the trapping of Li by dangling bonds and defects sites also contributes to the larger irreversible capacity loss in the first discharge.
文摘In this article, we study modified nano-hydroxyapatite (HAp) by nano manganese oxide (Mn3O4) as adsorbent material to remove iron ions from groundwater. Different parameters were studied to option optimum conditions of removing such as contact time, pH, initial concentration, a dosage of adsorbent, agitation speed and temperature. Kinetics studies included first order (R2 = 0.915), pseudo-first order (R2 = 0.936), second order (R2 = 0.948), pseudo-second order (R2 = 0.995), Elovich equation model (R2 = 0.977), intraparticle diffusion (R2 = 0.946), Natarajan and Khalaf (R2 = 0.915) were carried out, the obtained results revealed that the pseudo-second order is the best to describe the adsorption process because the correlation coefficient is approaching one (R2 = 0.995). Adsorption isotherm was calculated by using Freundlich, Langmuir and Temkin constants, adsorption capacity from Langmuir model was 0.606 mg/g. Thermodynamic parameters (ΔG, ΔH = ?51 KJ/mol, and ΔS = ?142 (KJ/mol)) for the adsorption process were also calculated and discussed.
文摘In order to improve the purification properties of polysulfone (PSF) ultrafiltration membranes (UFM), nano-graphene oxide (nano-GO) was taken as modifier, and the physical blending process was adopted in our experiment. The microstructure, surface morphology and functional groups of modified UFM have been characterized respectively by scanning electron microscopy, atomic force microscopy and Fourier transform infrared spectroscopy, and the static contact angle between the membrane surface and the water droplet has also been detected to show the change of its hydrophilicity. Through experiments, it has been found that modified UFM has larger and more developed finger micro-pores, and there exist a large number of -OH groups on its surface, and also its hydrophilicity has been enhanced. The result of the experiments show that the modified UFM may keep rejection above 97% and its water flux can be reached at about 219.1 L/(m2·h) under pressure of 1 bar if 0.4 wt% of nano-GO was added. Additionally, the nano-GO can increase the flux recovery radio (FRR) of the membranes, and the maximum FRR was observed as 74.4% if 0.3 wt% of nano-GO was appended.
文摘Magnetically separable CuO nanoparticles supported on graphene oxide（Fe3O4 NPs/GO-CuO NPs） is synthesized and characterized for the preparation of propargylamines in EtOH,at 90 C.Fe3O4 NPs/GOCuO NPs is found to be an efficient catalyst for the A^3-coupling of aldehydes,amines,and alkynes through C-H activation.Both aromatic and aliphatic aldehydes and alkynes are combined with secondary amines to provide a wide range of propargylamines in moderate to excellent yields.
文摘A kind of new nano composite with ultraviolet （UV） ray resistance and high temperature stability was prepared by in-situ polymerization in low temperature. Polysulfonamide （PSA） was synthesized with 4, 4＇-diaminodiphenyl sulfone （DDS） and terephthaloyl chloride （TPC） in the common solvent N, N-Dimethyl- -acetamide （DMAc）. Nano filler is a certain nano titanium oxide modified by silicon oxide （TMS）, which plays the role of UV resistance additives. Properties of the novel composite materials were characterized by Atomic Force microscopy （AFM）, thermal gravimetric Analysis （TGA） and Ultraviolet Spectroscopy. AFM had showed the sizes and distributions of TMS particles in the nanocomposite. Ultraviolet Spectroscopy for the nanocomposites showed a large absorption in UV band. TGA showed the decomposition temperature was increased over ten degrees with 0.5% wt TMS for this nanocomposite compared with pure PSA.
基金Project(50372020) supported by the National Natural Science Foundation of China
文摘In order to improve optical property of the multi-walled carbon nanotubes(MWNTs),MWNTs were decorated with europium oxide(Eu2O3) nanoparticles by using co-deposition method. The MWNTs/Eu2O3 composites were examined by XRD,scanning electron microscopy,transmission electron microscopy,and VUV-Vis Luminescence spectroscopy and citric acid(CA) molecules were introduced onto the surface of MWNTs. The results show that there are many oxygenated functional groups on the surface of the MWNTs after the treatment of mixture acid,such as carboxy,hydroxl,carbony and amidocyanogen. The results of electron microscopy illuminate that the MWNTs are coated by nano-europium oxide after annealed at 750℃. The MWNTs/Eu2O3 composite emits much strong red light at about 610 nm under UV excitation.
文摘Graphene oxide (GO) is a graphene derivatives that has oxygen-containing functional groups on the graphene basal plane, such as hydroxyl, carbonyl, epoxy and carboxyl groups. GO is considered as a promising material for biological applications owing to its excellent surface functionalizability, high specific suface area and good biocompatibility. In this study, GO/chitosan hybrid scaffolds were prepared for tissue engineering. Nano silver was loaded into the scaffold to improve its antibacterial ability and biomimetic Ca-P coatings were deposited on the scaffold surface to enhance its osteoconductivity. First, GO was prepared by the chemical oxidization of graphite. Secondly, nano-Ag loaded GO was prepared by chemical reducing Ag ions in GO solutions. Then, nano-Ag loaded GO solution was mixed with CS solution to form GO-CS gel. Chitosan (CS) and GO were crosslinked by electrostatic interactions between oxygen-containing functional groups of GO and NH2 groups of CS. The gel were freeze dried to produce nano-Ag loaded GO/CS hybrid porous scaffolds. Finally, the as-prepared scaffolds were immersed the into a supersaturated calcium phosphate solution (SCPS) for 7 days to deposite CaP coatings on the surface of the micropores. SEM images showed that nano-Ag uniformly distributed in the scaffold and the CaP covered most of the scaffold surfaces. In vitro cell culture and antimicrobial test indicated the biomimetic mineralized Ag-CS-GO scaffolds have good osteoconductivity and bactericidal ability.
基金the National Natural Science Foundation of China(No.51675491)
文摘Organic polymer materials were used as a layer of adhesive into the graphene sheet between the layers to enhance the interaction force between the nano-structure to achieve excellent mechanical properties and barrier properties. PLA with good flowability and easy processing was selected. The mechanical properties and barrier properties of the graphene-based composites were improved by the use of PLA for good flowability, making it easy to enter the GO layer as a binder. Three methods of preparation of GO/PLA homogeneous composite membranes were designed by vacuum filtration. The experimental results show that the injection of PLA as a molecular binder into the GO layer can effectively mimic the nano-structure, and enhance the intergranular force of the graphene molecules and the compatibility with the polymer matrix.
