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
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
以T300碳纤维经超声波化学镀镍制成的导电镀镍碳纤维作为电磁屏蔽体,以在丁醇/水溶液体系中采用界面聚合法制备的纳米结构聚苯胺为吸波体,与环氧乙烯基酯树脂复合,制得兼具电磁屏蔽与吸波功能的电磁防护碳纤维复合材料,研究了它的力学...以T300碳纤维经超声波化学镀镍制成的导电镀镍碳纤维作为电磁屏蔽体,以在丁醇/水溶液体系中采用界面聚合法制备的纳米结构聚苯胺为吸波体,与环氧乙烯基酯树脂复合,制得兼具电磁屏蔽与吸波功能的电磁防护碳纤维复合材料,研究了它的力学性能、电磁屏蔽性能、吸波性能、微观形貌等。结果表明:控制碳纤维化学镀镍的施镀时间、纳米结构聚苯胺的用量,可得到具有良好力学性能、电磁屏蔽性能、吸波性能的电磁防护碳纤维复合材料。当化学镀镍的施镀时间为20 min、纳米结构聚苯胺的用量为3.5wt%时,复合材料的拉伸强度为894.3 MPa,屏蔽效能为43~72 d B(10 k Hz^4 GHz),在10.77~18 GHz范围内,反射率≤-10 d B,峰值-23.2 d B(13.62 GHz)。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.
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。
文摘以T300碳纤维经超声波化学镀镍制成的导电镀镍碳纤维作为电磁屏蔽体,以在丁醇/水溶液体系中采用界面聚合法制备的纳米结构聚苯胺为吸波体,与环氧乙烯基酯树脂复合,制得兼具电磁屏蔽与吸波功能的电磁防护碳纤维复合材料,研究了它的力学性能、电磁屏蔽性能、吸波性能、微观形貌等。结果表明:控制碳纤维化学镀镍的施镀时间、纳米结构聚苯胺的用量,可得到具有良好力学性能、电磁屏蔽性能、吸波性能的电磁防护碳纤维复合材料。当化学镀镍的施镀时间为20 min、纳米结构聚苯胺的用量为3.5wt%时,复合材料的拉伸强度为894.3 MPa,屏蔽效能为43~72 d B(10 k Hz^4 GHz),在10.77~18 GHz范围内,反射率≤-10 d B,峰值-23.2 d B(13.62 GHz)。
