An effect of heating and stirring in a facile wet chemical route to synthesize entangled nanofibrous mesh of doped polyaniline(PANI) was reported. The structural, morphological, and optical properties of PANI nano-fib...An effect of heating and stirring in a facile wet chemical route to synthesize entangled nanofibrous mesh of doped polyaniline(PANI) was reported. The structural, morphological, and optical properties of PANI nano-fibers were found to be dependent on synthesis temperature and stirring. The XRD analysis confirms nano PANI formation with 2θ peaks around 15°, 21°, and 25° for(011),(020), and(200) crystal planes, respectively. The average crystallite size varies between 25 nm to 60 nm due to change in synthesis conditions. The SEM analysis reveals the clustered granule formation for PANI sample synthesized at 28 and 60 ℃ under continuous stirring, whereas, unstirred synthesis at 60 ℃ shows entangled nano-fibrous mesh morphology. The TGA study shows better thermal stability for PANI mesh over granular PANI. The FTIR spectra validates the emeraldine salt PANI formation with peaks corresponding to C-H, C-N, N=Q=N, N=B=N, and N-H vibration bands. The UV-Vis analysis shows the major absorbance peaks around λ: 340 nm(π-π* transition of benzenoid ring), and λ: 800 nm(π-π*, polaron-π*, π-polaron transitions). The dense entangled nano-fibrous coating of PANI synthesized at 60 ℃ without stirring shows highest electrical conductivity of 3.79 S·cm^-1.展开更多
The conducting polyaniline （PANI） prepared by three chemical oxidative polymerization pathways including microemulsion, emulsion and aqueous solution methods were studied and compared. Their structures, morphologies...The conducting polyaniline （PANI） prepared by three chemical oxidative polymerization pathways including microemulsion, emulsion and aqueous solution methods were studied and compared. Their structures, morphologies and properties were characterized using FT-IR, XRD, TEM and TGA. PANI particles formed in aqueous solution have a smallest size and doping HCl enables to increase their conductivity. In contrast, PANI particles prepared by emulsion method have the highest thermal stability and conductivity and more ordered morphology. Rather different from these two methods, microemulsion approach allows forming nanocomposite PANI with tube-like nanostructure.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 biodiesel prepared from Xanthoceras Sorbiflia Bunge Oil catalyzed by Ce doped nano PO_4^(3-)/ZrO_2 was investigated. A maximum biodiesel yield of 91.83% was achieved at the concentration of Ce^(3+) up to 0.1 mol/L...The biodiesel prepared from Xanthoceras Sorbiflia Bunge Oil catalyzed by Ce doped nano PO_4^(3-)/ZrO_2 was investigated. A maximum biodiesel yield of 91.83% was achieved at the concentration of Ce^(3+) up to 0.1 mol/L, calcination temperature 500 °C, calcination time 3.0 h, and the concentration of phosphoric acid of 3.5 mol/L. Ce-nano PO_4^(3-)/ZrO_2 catalyst activities were correlated with the observed physico-chemical characteristics derived from scanning electron microscopy(SEM), FT-infrared(FT-IR), X-ray diffraction(XRD), thermogravimetric(TG) and Brunauer-Emmett-Teller(BET) analysis. The delayed crystallization of ZrO_2 made surface oxides have more defects which were beneficial to the adsorption of PO_4^(3-) by the concentration increment of Ce^(3+). The chemical composition of synthesized biodiesel was confirmed by gas chromatography(GC). The characteristics of Xanthoceras Sorbiflia Bunge oil were found within the optimal range in accordance with Chinese No. 0 diesel standard as a substitute diesel fuel.展开更多
Nano-fibrous polyaniline was synthesized on stainless steel electrode in 0.5mol·L-1 H2SO4 solution by pulse galvanostatic method. The effects of synthetic conditions of pulse galvanostatic method on the electro...Nano-fibrous polyaniline was synthesized on stainless steel electrode in 0.5mol·L-1 H2SO4 solution by pulse galvanostatic method. The effects of synthetic conditions of pulse galvanostatic method on the electroactivity of polyaniline were investigated. The results show that the electroactivity of polyaniline film strongly depends on the synthetic conditions, such as the ratio of “on time” to “off time”(ton/toff), frequency, monomer concentration, temperature and mean current density. Different electroactivities of polyaniline are caused by different morphologies of polyaniline. The nano-fibrous polyaniline has higher electroactivity than polyaniline with other morphologies. Under the following conditions: mean current density of pulse galvanostatic method 13mA·cm-2, ton/toff 1, frequency 200Hz, monomer concentration 0.3mol·L-1 and temperature 20℃, nano-fibrous polyaniline film with the highest electroactivity can be obtained.展开更多
Biofouling is a major issue in aquaculture cages and nano materials based antifouling strategies became more prominent in recent years.Polyethylene aquaculture cage net surface which is modified with polyaniline and n...Biofouling is a major issue in aquaculture cages and nano materials based antifouling strategies became more prominent in recent years.Polyethylene aquaculture cage net surface which is modified with polyaniline and nano-copper oxide(CuO),reported to have biofouling resistance.Leaching of nano CuO from the net to the aquatic environment and its bioaccumulation in fish is the major concern against the technology adoption.The present study aimed to understand the accumulation of copper in fishes grown in a nano CuO treated aquaculture cage net.Studied the leaching pattern of nano CuO,biofouling inhibition and changes in strength of the cage net due to the nano CuO treatments.Fishes grown in the treated cages exhibited normal growth characteristics with no signs of abnormalities and also copper in their organs were within the prescribed standard limit.The CuO treated cage net exhibited excellent biofouling resistance and the percentage of occlusion of mesh by foulers were 56.77%more efficient than untreated cage net.Rate of nano CuO leached to the aquatic system was less than 8μg/g⋅d.The fouling organism assemblage on untreated and treated net was 18 and 11 species,respectively.Major calcareous shelled foulers were absent on treated nets.The study highlighted the potential application of nano CuO treatment to control biofouling in aquaculture cages.展开更多
An access to an increase in the information storage capacity is to reduce memory units to a nano-scale. There fore, we used carboxylized phenyl-capped polyaniline tetramer (PCAT) as the functional component and silica...An access to an increase in the information storage capacity is to reduce memory units to a nano-scale. There fore, we used carboxylized phenyl-capped polyaniline tetramer (PCAT) as the functional component and silica as the carrier to prepare PCAT/silica composite nano-particles (= 60 nm) with a structure of core-shell. The functionalized particles were two-dimensionally arrayed on substrates such as silicon, glass and ITO glass at pH 3.SEM and AFM results proved the arraying regularity of these particles under any given conditions, and the electrostatic force microscopy showed their response to +3 V bias applied.展开更多
采用循环伏安法、微分脉冲伏安法、交流阻抗谱以及计时电流法等电化学方法,结合红外光谱、紫外-可见分光光度法、原子力显微镜、透射电子显微镜以及原子吸收光谱等辅助手段,表征了固定漆酶的聚苯胺-草酸钴纳米复合物的化学组成、结构和...采用循环伏安法、微分脉冲伏安法、交流阻抗谱以及计时电流法等电化学方法,结合红外光谱、紫外-可见分光光度法、原子力显微镜、透射电子显微镜以及原子吸收光谱等辅助手段,表征了固定漆酶的聚苯胺-草酸钴纳米复合物的化学组成、结构和形貌,测试了纳米复合物固酶前后的导电性能的变化,研究了纳米复合物修饰电极上固定漆酶的直接电化学行为,评估了该电极的催化氧还原效能以及作为电化学传感器检测氧分子的性能。实验结果表明该电极在不含电子介体的溶液中以酶活性中心T2作为首要电子受体,将得到电子传递给化学吸附的氧气使其被电还原,其表观电子迁移速率为0.017 s^(-1),且具有良好的催化氧还原性能(氧还原起始电位:460 m V vs NHE,转化氧分子为水的表观速率常数为2.6×10-4 s^(-1)),酶电催化氧还原为水分子步骤为反应的速控步。该电极作为电化学传感器对氧具有极低检测限(0.20μmol·L^(-1)),宽线性响应范围(0.4~7.5μmol·L^(-1))以及对底物高亲和力(KM=122.4μmol·L^(-1))等优势。展开更多
文摘An effect of heating and stirring in a facile wet chemical route to synthesize entangled nanofibrous mesh of doped polyaniline(PANI) was reported. The structural, morphological, and optical properties of PANI nano-fibers were found to be dependent on synthesis temperature and stirring. The XRD analysis confirms nano PANI formation with 2θ peaks around 15°, 21°, and 25° for(011),(020), and(200) crystal planes, respectively. The average crystallite size varies between 25 nm to 60 nm due to change in synthesis conditions. The SEM analysis reveals the clustered granule formation for PANI sample synthesized at 28 and 60 ℃ under continuous stirring, whereas, unstirred synthesis at 60 ℃ shows entangled nano-fibrous mesh morphology. The TGA study shows better thermal stability for PANI mesh over granular PANI. The FTIR spectra validates the emeraldine salt PANI formation with peaks corresponding to C-H, C-N, N=Q=N, N=B=N, and N-H vibration bands. The UV-Vis analysis shows the major absorbance peaks around λ: 340 nm(π-π* transition of benzenoid ring), and λ: 800 nm(π-π*, polaron-π*, π-polaron transitions). The dense entangled nano-fibrous coating of PANI synthesized at 60 ℃ without stirring shows highest electrical conductivity of 3.79 S·cm^-1.
基金Funded by the National Natural Science Foundation of China ( No. 50771020)
文摘The conducting polyaniline （PANI） prepared by three chemical oxidative polymerization pathways including microemulsion, emulsion and aqueous solution methods were studied and compared. Their structures, morphologies and properties were characterized using FT-IR, XRD, TEM and TGA. PANI particles formed in aqueous solution have a smallest size and doping HCl enables to increase their conductivity. In contrast, PANI particles prepared by emulsion method have the highest thermal stability and conductivity and more ordered morphology. Rather different from these two methods, microemulsion approach allows forming nanocomposite PANI with tube-like nanostructure.
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 Key Laboratory of Bio-based Material Science&Technology(Northeast Forestry University)Ministry of Education(No.SWZCL2016-10)+2 种基金Natural Science Foundation of Inner Mongolia(No.2018BS03004)Talent Development Fund of Inner MongoliaNational Majority R&D Program of China(2017YFD06002025)
文摘The biodiesel prepared from Xanthoceras Sorbiflia Bunge Oil catalyzed by Ce doped nano PO_4^(3-)/ZrO_2 was investigated. A maximum biodiesel yield of 91.83% was achieved at the concentration of Ce^(3+) up to 0.1 mol/L, calcination temperature 500 °C, calcination time 3.0 h, and the concentration of phosphoric acid of 3.5 mol/L. Ce-nano PO_4^(3-)/ZrO_2 catalyst activities were correlated with the observed physico-chemical characteristics derived from scanning electron microscopy(SEM), FT-infrared(FT-IR), X-ray diffraction(XRD), thermogravimetric(TG) and Brunauer-Emmett-Teller(BET) analysis. The delayed crystallization of ZrO_2 made surface oxides have more defects which were beneficial to the adsorption of PO_4^(3-) by the concentration increment of Ce^(3+). The chemical composition of synthesized biodiesel was confirmed by gas chromatography(GC). The characteristics of Xanthoceras Sorbiflia Bunge oil were found within the optimal range in accordance with Chinese No. 0 diesel standard as a substitute diesel fuel.
基金Project(50473022) supported by the National Natural Science Foundation project supported by the State Key Laboratoryof Chemo/Biosensing and Chemometrics of China
文摘Nano-fibrous polyaniline was synthesized on stainless steel electrode in 0.5mol·L-1 H2SO4 solution by pulse galvanostatic method. The effects of synthetic conditions of pulse galvanostatic method on the electroactivity of polyaniline were investigated. The results show that the electroactivity of polyaniline film strongly depends on the synthetic conditions, such as the ratio of “on time” to “off time”(ton/toff), frequency, monomer concentration, temperature and mean current density. Different electroactivities of polyaniline are caused by different morphologies of polyaniline. The nano-fibrous polyaniline has higher electroactivity than polyaniline with other morphologies. Under the following conditions: mean current density of pulse galvanostatic method 13mA·cm-2, ton/toff 1, frequency 200Hz, monomer concentration 0.3mol·L-1 and temperature 20℃, nano-fibrous polyaniline film with the highest electroactivity can be obtained.
文摘Biofouling is a major issue in aquaculture cages and nano materials based antifouling strategies became more prominent in recent years.Polyethylene aquaculture cage net surface which is modified with polyaniline and nano-copper oxide(CuO),reported to have biofouling resistance.Leaching of nano CuO from the net to the aquatic environment and its bioaccumulation in fish is the major concern against the technology adoption.The present study aimed to understand the accumulation of copper in fishes grown in a nano CuO treated aquaculture cage net.Studied the leaching pattern of nano CuO,biofouling inhibition and changes in strength of the cage net due to the nano CuO treatments.Fishes grown in the treated cages exhibited normal growth characteristics with no signs of abnormalities and also copper in their organs were within the prescribed standard limit.The CuO treated cage net exhibited excellent biofouling resistance and the percentage of occlusion of mesh by foulers were 56.77%more efficient than untreated cage net.Rate of nano CuO leached to the aquatic system was less than 8μg/g⋅d.The fouling organism assemblage on untreated and treated net was 18 and 11 species,respectively.Major calcareous shelled foulers were absent on treated nets.The study highlighted the potential application of nano CuO treatment to control biofouling in aquaculture cages.
文摘An access to an increase in the information storage capacity is to reduce memory units to a nano-scale. There fore, we used carboxylized phenyl-capped polyaniline tetramer (PCAT) as the functional component and silica as the carrier to prepare PCAT/silica composite nano-particles (= 60 nm) with a structure of core-shell. The functionalized particles were two-dimensionally arrayed on substrates such as silicon, glass and ITO glass at pH 3.SEM and AFM results proved the arraying regularity of these particles under any given conditions, and the electrostatic force microscopy showed their response to +3 V bias applied.
文摘采用循环伏安法、微分脉冲伏安法、交流阻抗谱以及计时电流法等电化学方法,结合红外光谱、紫外-可见分光光度法、原子力显微镜、透射电子显微镜以及原子吸收光谱等辅助手段,表征了固定漆酶的聚苯胺-草酸钴纳米复合物的化学组成、结构和形貌,测试了纳米复合物固酶前后的导电性能的变化,研究了纳米复合物修饰电极上固定漆酶的直接电化学行为,评估了该电极的催化氧还原效能以及作为电化学传感器检测氧分子的性能。实验结果表明该电极在不含电子介体的溶液中以酶活性中心T2作为首要电子受体,将得到电子传递给化学吸附的氧气使其被电还原,其表观电子迁移速率为0.017 s^(-1),且具有良好的催化氧还原性能(氧还原起始电位:460 m V vs NHE,转化氧分子为水的表观速率常数为2.6×10-4 s^(-1)),酶电催化氧还原为水分子步骤为反应的速控步。该电极作为电化学传感器对氧具有极低检测限(0.20μmol·L^(-1)),宽线性响应范围(0.4~7.5μmol·L^(-1))以及对底物高亲和力(KM=122.4μmol·L^(-1))等优势。
