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CHARACTERIZATION AND ANTIBACTERIAL ACTIVITY OF ZnO NANOPARTICLES SYNTHESIZED BY CO PRECIPITATION METHOD
摘要： Objective: In the present study the antibacterial activity of zinc oxide (ZnO) nanoparticles was investigated against gram negative (Escherichia coli and Proteus vulgaris) and gram positive (Staphylococcus aureus and Streptococcus mutans) organisms. Methods: The synthesis of ZnO nanoparticles was carried out by co-precipitation method using zinc sulfate and sodium hydroxide as precursors. These nanoparticles were characterized by XRD (X-Ray Diffraction), FTIR (Fourier Transform Infrared Radiation), UV-Visible spectroscopy and SEM (Scanning Electron Microscope) with EDX (Energy Dispersive X-ray analysis). As well as antibacterial activity and minimum inhibitory concentration of the nanoparticles were carried out by agar well diffusion method and broth dilution method respectively against gram negative (Escherichia coli and Proteus vulgaris) and gram positive (Staphylococcus aureus and Streptococcus mutans) bacteria. Results: The average crystallite size of ZnO nanoparticles was found to be 35 nm by X-ray diffraction. The vibration bands at 450 and 603 cm-1 which were assigned for ZnO stretching vibration were observed in FTIR spectrum. The optical absorption band at 383 nm was obtained from UV-Visible spectrum. Spherical shape morphology was observed in SEM studies. The antibacterial assay clearly expressed that E. coli showed a maximum zone of inhibition (32±0.20 mm) followed by Proteus vulgaris (30±0.45 nm) at 50 mg/ml concentration of ZnO nanoparticles. Conclusion: Zinc oxide nanoparticles have exhibited good antibacterial activity with gram negative bacteria when compared to gram positive bacteria.
关键词： EDX,SEM,MIC,FTIR,UV-VISIBLE spectroscopy,XRD,ZnO nanoparticles
更新于2025-11-21 11:18:25
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Effect of electron beam irradiation on structure, morphology, and optical properties of PVDF-HFP/PEO blend polymer electrolyte films
摘要： The effect of 8 MeV energy electron beam (EB) on poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP)/poly-ethylene oxide (PEO) (@ w/w 90:10, PHP10) polymer blend films have been prepared and studied. The change in structure, morphology, and optical properties at 40, 80, and 120 kGy EB doses were investigated. The effect of the radiation process may responsible to occurs the degradation (chain scission) and chain link (cross linking) which are confirmed by the FT-IR analysis. The band at 1401 cm?1 corresponding to the –CH2– bending or scission mode have shifted to 1397 cm?1 after 120 kGy EB dose is due to the intermolecular interaction and the changes of the macromolecular chain by breaking of bonds with increased EB dose was observed. The XRD pattern shows decreased in the crystallinity from 60.03 to 23.42% and increased amorphousity for 120 kGy EB dose the and the surface morphology was drastically changed by decreasing the size of spherulites upon increased EB dose. The increase in optical absorption and the shifting of wavelength toward a higher end (red shift) was observed after the irradiation. The energy band gaps (Eg), and Urbach energy were estimated and they are found to be decreased, but the number of carbon atoms in a cluster of was increased with increased EB dose. The obtained results notice that the physical properties of polymer blend electrolytes can be improved by EB irradiation to use in different potential applications.
关键词： Polymer electrolyte,FESEM,UV–visible spectroscopy,Structural analysis,Electron beam irradiation
更新于2025-11-21 11:01:37
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Physical, Thermal and Spectroscopic Studies on Biofield Treated p-Dichlorobenzene
摘要： Para-dichlorobenzene (p-DCB) is widely used as a chemical intermediate in manufacturing of dyes, pharmaceuticals, polymers and other organic synthesis. The aim of present study was to evaluate the impact of biofield treatment on physical, thermal, and spectroscopic properties of p-dichlorobenzene. The p-dichlorobenzene sample was divided into two groups that served as treated and control. The treated group received Mr. Trivedi’s biofield treatment. Subsequently the control and treated samples were evaluated using X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and UV-Vis spectroscopy. XRD result showed an increase in crystallite size (4.93%) along with alteration in peak intensity of treated sample as compared to control. Furthermore, DSC analysis results showed that the latent heat of fusion of treated p-dichlorobenzene was considerably reduced by 8.66% as compared to control. The reduction in melting point of treated sample (54.99°C) was also observed as compared to control (57.01°C) p-dichlorobenzene. Moreover, TGA/DTG studies showed that Tmax (temperature, at which sample lost maximum of its weight) was increased by 6.26% and weight loss per degree celsius (°C) was decreased by 12.77% in biofield treated p-dichlorobenzene as compared to control sample. It indicates that thermal stability of treated p-dichlorobenzene sample might increase as compared to control sample. However, no change was found in UV-Vis spectroscopic character of treated p-dichlorobenzene as compared to control. These findings suggest that biofield treatment has significantly altered the physical and thermal properties of p-dichlorobenzene, which could make it more useful as a chemical intermediate.
关键词： Differential scanning calorimetry,Para-dichlorobenzene,Thermogravimetric analysis,and UV-Visible spectroscopy,Biofield treatment,X-ray diffraction study
更新于2025-09-23 15:23:52
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Simultaneous quantitative analysis of indomethacin and benzoic acid in gel using ultra-violet-visible spectrophotometry and chemometrics
摘要： BACKGROUND: In order to manufacture pharmaceutical products, real-time monitoring in the manufacturing process is necessary, but large equipment cost is required to achieve it. OBJECTIVE: The aim of this research is to use ultra-violet-visible spectroscopy along with chemometrics procedure to simultaneously quantitative analysis of indomethacin (IMC) and benzoic acid (BA) in the gel during pharmaceutical manufacturing process. METHODS: The gel preparations were contained of 0.1–1.5% IMC, 0.015–0.225% BA, 2% carbopol? 941 and 95% ethanol solution. The calibration models were constructed using the partial least square regression (PLS). RESULTS: The relationships of the measured and predicted concentrations for both IMC and BA had linear plots. The developed PLS calibration models were used to monitor the IMC and BA concentrations during mixing of the gels by the planetary centrifugal and conventional mixers, respectively. IMC and BA were gradually dispersed, dissolved and completely homogeneous within 30 min by the centrifugal mixer. In contrast, IMC and BA were slowly dispersed, dissolved and completely homogeneous at more than 60 min by the conventional mixer. CONCLUSIONS: The ultra-violet-visible spectrophotometric method couples with multivariate chemometric techniques for quantitative data analysis were successfully applied for the simultaneous determination of major component IMC and trace component BA in the gel.
关键词： benzoic acid,indomethacin,partial least square regression,Ultra-violet-visible spectroscopy,process analysis technology,process monitoring
更新于2025-09-23 15:22:29
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Surface characteristics of nitrogen ion implanted CR-39 polymer: RBS studies
摘要： This paper investigates the surface characteristics of nitrogen ion implanted CR- 39 polymer. The specimens were implanted with 100 keV N+ beam to various ?uences of 1 × 1015, 1 × 1016 and 2 × 1016 ions cm?2. The ion implantation induced modi?cations in these specimens were analyzed by Rutherford Backscattering Spectrometry (RBS) and UV- Visible spectroscopy. RBS studies reveal that the structure of the virgin CR-39 specimen has been modi?ed completely after N+ implantation. The spatial distribution in the form of carbonization, projected range, retained dose and atomic concentration of implanted nitrogen have been estimated using RBS spectra. RUMP analysis revealed that for the implanted specimen at ?uence 2 × 1016 N+ cm?2, the carbon concentration increases from 32 at.% to 43 at.% and oxygen concentration from 19 at.% to 26 at.% respectively near the surface. This increase in the concentration of carbon points towards the carbonization in the implanted layers. Furthermore, UV–Visible transmission spectra demonstrate that for higher ?uences, almost complete UV region is blocked; making CR-39 a viable functional material for UV blocking devices.
关键词： RBS,Ion implantation,UV–Visible spectroscopy,CR-39
更新于2025-09-23 15:21:01
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Interaction of Zinc Oxide and Copper Oxide Nanoparticles with Chlorophyll: A Fluorescence Quenching Study
摘要： The present study aims to investigate the interactions of zinc oxide nanoparticles and copper oxide nanoparticles with the major photosynthetic pigment chlorophyll using ultraviolet-visible, steady state, and time resolved laser induced fluorescence spectroscopy. The steady state fluorescence measurements show that zinc oxide and copper oxide nanoparticles quench the fluorescence of chlorophyll in concentration-dependent manner. The Stern-Volmer plot for the chlorophyll-zinc oxide nanoparticles is linear, and the value of quenching constant has been observed to increase with temperature indicating the possibility of dynamic quenching. A decrease in the lifetime of chlorophyll with increase in the concentration of zinc oxide nanoparticles confirms the involvement of dynamic quenching in the chlorophyll–zinc oxide nanoparticle interaction. In the case of copper oxide nanoparticles, the Stern-Volmer plot deviates from linearity observed in the form of upward curvature depicting the presence of both static and dynamic quenching. In addition, the lifetime of chlorophyll decreases with increase in the concentration of copper oxide nanoparticles displaying the dominance of dynamic quenching in the chlorophyll-copper oxide nanoparticle interaction. The decrease observed in the value of binding constant with increasing temperature and negative values of change in enthalpy, entropy, and Gibb’s free energy indicates that van der Waal and hydrogen bonding are the prominent forces during the interaction of chlorophyll with both zinc oxide and copper oxide nanoparticles and that the process is spontaneous and exothermic. The interaction of zinc oxide and copper oxide nanoparticles with chlorophyll occurs through electron transfer mechanism. The obtained results are useful in understanding the sensitization processes involving chlorophyll and zinc oxide and copper oxide nanoparticles.
关键词： chlorophyll and nanoparticles,molecular interaction,ultraviolet-visible spectroscopy,laser-induced fluorescence spectroscopy,Attenuated total reflectance–Fourier transform infrared spectroscopy,steady state and time resolved fluorescence,X-ray diffraction
更新于2025-09-19 17:15:36
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SPR responsive xylenol orange functionalized gold nanoparticles- optical sensor for estimation of Al3+ in water
摘要： Xylenol orange functionalized gold nanoparticles (XO-AuNPs), prepared by reducing HAuCl4 in presence of xylenol orange were found to be selective and sensitive for optical sensing of Al3+ in water. XO-AuNPs nanoparticles were characterized by transmission electron microscopy (TEM), x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS); the nanoparticles formed were of spherical shape and of uniform size of 3-12 nm. The interaction between Al3+ and XO-AuNPs at pH ~3 was studied by XPS analysis. XPS and TEM studies revealed that aggregation of XO-AuNPs in the presence of Al3+ takes place through analyte induced cross-linkage mechanism. Al3+ induced selective aggregation of the XO-AuNPs lead to a visual change in color of the colloidal solution from deep red to blue. The changes in characteristic absorption peak of XO-AuNPs were monitored; the ratio of A550nm/A515nm was used to quantify the concentration of Al3+ in water samples. The method gave a linear response from 50?300 ppb (R2 = 0.985) of Al3+ in drinking water with a detection limit of 12 ppb. The proposed method did not suffer any major interference from concomitant transition metal ions and anions. The developed method was simple, rapid and useful for determination of Al3+ in drinking water samples.
关键词： Aluminium,UV-visible spectroscopy,Optical sensor,Gold nanoparticles,X-ray photoelectron spectroscopy,Xylenol orange
更新于2025-09-16 10:30:52
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Measurement and Analysis of Radiation Calibration Uncertainty of Multi-Band Polarization Imager
摘要： The principle of multi-band polarization imager is introduced. In order to verify the accuracy, instrument was tested and analyzed by radiation calibration. The radiation calibration accuracy is better than 2%, which meets the design requirements.
关键词： Polarimetry,Radiometry,Visible Spectroscopy
更新于2025-09-16 10:30:52
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Facile Synthesis and Characterization of Zn2V2O7 Nanoparticles
摘要： Zinc vanadate (Zn2V2O7) nanoparticles were synthesized by facile thermal decomposition method. The as-synthesized Zn2V2O7 nanoparticles were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, Ultraviolet-visible (DRS-UV-visible) spectroscopy, photoluminescence spectroscopy, scanning electron microscopy and transmission electron microscopy. X-ray diffraction shows that the synthesized sample belongs to Zn2V2O7. FT-IR confirms the formation of Zn-O bond in the sample. UV-visible and photoluminescence studies reveal the optical property of the Zn2V2O7 nanoparticles. The nanobar-like morphology was confirmed by both SEM and TEM analysis.
关键词： UV-visible spectroscopy,Zinc vanadate,Nanoparticles,XRD pattern
更新于2025-09-11 14:15:04
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Preparation of TiO <sub/>2</sub> nanoparticles by hydrolysis of TiCl <sub/>4</sub> using water and glycerol solvent system
摘要： The anatase phase TiO2 nanoparticles (NPs) were synthesized by precipitation method using TCl4 as a precursor in a new reaction medium containing water and glycerol. The as-synthesized photocatalysts were characterized by Raman spectroscopy, Fourier Transform Infra-red Spectroscopy (FT-IR), UV-Visible spectroscopy and Field Emission Scanning Electron Microscopy (FESEM). The Raman spectra indicate the formation of crystalline anatase phase TiO2 NPs after calcination at 300 and 4000C. TiO2 NPs formation was confirmed by observing the major characteristic, FT-IR vibration bands of Ti-O network. The band gap calculated from UV-Vis DRS spectra ranged from 3.02-3.28 eV. FESEM images exhibit spherical shape TiO2 NPs in the form of nano-clusters with crystallite sizes ranged from 9.50-26.14 nm. FESEM images show that as the calcination temperature increases, the sizes of the TiO2 NPs also increase. The inclusion of glycerol promotes the formation of smaller particles and lowers the band gap of TiO2 NPs.
关键词： precipitation method,TiO2 nanoparticles,hydrolysis,anatase phase,Raman spectroscopy,FESEM,UV-Visible spectroscopy,water and glycerol solvent system,FT-IR,TiCl4
更新于2025-09-09 09:28:46