Antibacterial and Morphological Studies of Electrospun Silver-Impregnated Polyacrylonitrile Nanofibre

Silver-impregnated polyacrylonitrile (PAN) nanofibre was prepared through electrospinning process. Infra-red spectroscopy (FT-IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Thermo gravimetric analyses (TGA/DTA) were used to characterize PAN and PAN/Ag composites. The XRD results reflects decrease in the crystallinity of PAN as it is been modified with Ag. Antibacterial activity of PAN/Ag was also investigated

Phase Behavior of Aqueous Na-K-Mg-Ca-CI-NO3 Mixtures: Isopiestic Measurements and Thermodynamic Modeling

A comprehensive model has been established for calculating thermodynamic properties of multicomponent aqueous systems containing the Na{sup +}, K{sup +}, Mg{sup 2+}, Ca{sup 2+}, Cl{sup -}, and NO{sub 3}{sup -} ions. The thermodynamic framework is based on a previously developed model for mixed-solvent electrolyte solutions. The framework has been designed to reproduce the properties of salt solutions at temperatures ranging from the freezing point to 300 C and concentrations ranging from infinite dilution to the fused salt limit. The model has been parameterized using a combination of an extensive literature database and new isopiestic measurements for thirteen salt mixtures at 140 C. The measurements have been performed using Oak Ridge National Laboratory's (ORNL) previously designed gravimetric isopiestic apparatus, which makes it possible to detect solid phase precipitation. Water activities are reported for mixtures with a fixed ratio of salts as a function of the total apparent salt mole fraction. The isopiestic measurements reported here simultaneously reflect two fundamental properties of the system, i.e., the activity of water as a function of solution concentration and the occurrence of solid-liquid transitions. The thermodynamic model accurately reproduces the new isopiestic data as well as literature data for binary, ternary and higher-order subsystems. Because of its high accuracy in calculating vapor-liquid and solid-liquid equilibria, the model is suitable for studying deliquescence behavior of multicomponent salt systems

Study on identification of leather industry wastewater constituents and its photocatalytic treatment

The present research work was intended to find out the useful information on identification, separation and photocatalytic degradation of organic compounds present in leather industry wastewater. The separation of organic compounds present in leather industry wastewater was carried out by solvent extraction. The separated crude extracted products were purified through column chromatography and characterized by UV–vis spectrophotometer, gas chromatography–mass spectrophotometer, liquid chromatography–mass spectrophotometer, 1H and 13C Fourier-transform nuclear magnetic resonance spectroscopy. The elemental analysis of wastewater and solid residue was carried out by inductively coupled plasma-optical emission and X-ray fluorescence spectroscopy. The organic compounds such as nonadec-1-ene, 2-phenylethanol, 2,4-di-tert-butylphenol and other organic compounds in the leather industry wastewater were identified. Out of these organic compounds, 2-phenylethanol was photocatalytically degraded using standard Degussa P-25 TiO2 (100 mg) photocatalyst under the irradiation of UV light. Result has been shown that 2-phenylethanol was transformed into 2-tert-butyl-4,6-dimethylphenol, 2,6-di-tert-butyl-4-methylphenol then the prolonged time (30 h) irradiation leads to 100 % degradation of 2-phenylethanol. Further possible degradation mechanism of 2-phenylethanol was proposed based on the electrospray ionization mass spectrometry analysis of degraded samples. The degradation of 2-phenylethanol was confirmed by chemical oxygen demand analysis of degraded samples. The physicochemical parameters such as pH, color, chemical oxygen demand, total dissolved solids, electrical conductivity and ionic chromatography analysis of the leather industry wastewater were also measured

In vitro activity of diethylcarbamazine on the infective larvae microfilariae and adult worms of Breinlia sergenti

10.1016/0020-7519(73)90072-6International Journal for Parasitology36803-807IJPY

In vitro activity of levamisole on the infective larvae, microfilariae and adult worms of Breinlia sergenti

10.1016/0020-7519(74)90107-6International Journal for Parasitology42207-210IJPY

Simulation and dSPACE Based Implementation of Various PWM Strategies for A New H-Type FCMLI Topology

Depending on the number of levels in output voltage, inverters can be divided into two categories: two level inverter and Multi Level Inverters (MLIs). An inverter topology for high voltage and high power applications that seems to be gaining interest is the MLI. In high power and high voltage applications, the two level inverters have some limitations in operating at high frequency mainly due to switching losses and constraints of device rating.In this paper, a three phase H + type FCMLI (Flying Capacitor MLI) using sinusoidal reference, third harmonic injection reference, 60 degree reference and stepped wave reference are initially developed using SIMULINK and then implemented in real time environment using dSPACE. In H-type FCMLI with R-load it is inferred that bipolar COPWM-C provides output with relatively low distortion for 60 degree reference and bipolar COPWM-C strategy is found to perform better since it provides relatively higher fundamental RMS output voltage for THI reference. The five level output voltages of the chosen MLIs obtained using the MATLAB and dSPACE based PWM (Pulse Width Modulation) strategies and the corresponding %THD (Total Harmonic Distortion), VRMS (fundamental), CF (Crest Factor) and FF (Form Factor) are presented and analyzed

Inflammatory Signature after Low Dose γ-Radiation in Mice Brain and Gut: Switch from Therapeutic Benefit to Inflammation

Low dose y-radiation (LDIR) has been used as curative/adjuvant/palliative treatment modality for a variety of medical conditions. However, LDIR has been casually linked to NFκB activation and inflammation. Here, we investigated the kinetics of cyto/chemokines and their influence on inflammation in normal tissues after LDIR. C57BL/6 mice exposed to LDIR (2–50cGy) and sacrificed after 1 h-8 days were examined for alterations in 95 cyto/chemokines in brain and gut (QPCR profiling) and selectively validated by assessing secreted levels (ELISA). Kinetics of LDIR-induced inflammation was assessed using DNA fragmentation and histomorphological changes in brain and gut. LDIR induced a dose-dependent upregulation of cyto/chemokines after 2–50cGy in both brain and gut. Two genes, Csf3 and Tnfa , were upregulated in a ‘dose- and tissue-independent’ manner. Transcriptional kinetics revealed induction of more genes both in brain and gut in early response time (1–48 h) after LDIR. Conversely, only few genes upregulated and more genes downregulated in these tissues after extended response (4–8 days) period. DNA fragmentation and histomorphological analysis revealed consistent dose-, time-and tissue-dependent inflammation after LDIR. Also, serum levels of TNF-α, VEGFA, IFN-γ, GM-CSF, MCP-1 reinstigates the inflammatory signature after LDIR. Together, these results suggest that LDIR significantly inflicts a dose- and tissue-dependent inflammation in normal tissues and this induced inflammation may equivocate over-time and, hence frequency of LDIR use may control the switch from therapeutic benefit to inflammatory response

Design of A New Three Phase Hybrid H-bridge and H-Type FCMLI for Various PWM Strategies

The inverters have to be designed to obtain a quality output voltage or a current waveform with a minimum amount of ripple content. In high power and high voltage applications the conventional two level inverters, however, have some limitations in operating at high frequency mainly due to switching losses and constraints of the power device ratings. Series and parallel combination of power switches in order to achieve the power handling voltages and currents. The conventional two level inverters produce THD levels around 60% even under normal operating conditions which are undesirable and cause more losses and other power quality problems too on the AC drives and utilities. Nowadays, multilevel inverters are widely used in power industry. Voltage unbalance problem is one of the major issues in working of multilevel inverter. In this paper, a three phase H-bridge + H-type FCMLI using sinusoidal reference, third harmonic injection reference, 60 degree reference and stepped wave reference are initially developed using SIMULINK and then implemented in real time environment using dSPACE. The five level output voltages of the chosen MLIs obtained using the MATLAB and dSPACE based PWM strategies and the corresponding % THD, VRMS (fundamental) , CF and FF are presented and analyzed. It is observed that bipolar COPWM-C provides output with relatively low distortion for sine reference and bipolar COPWM-B strategy is found to perform better since it provides relatively higher fundamental RMS output voltage for 60 degree reference

Nano-fibrous sulfonated poly(ether ether ketone) membrane for selective electro-transport of ions

[Display omitted] ▶ Electrospun nano−fibrous sulfonated poly (ether ether ketone) (ESPEEK) membrane was fabricated onto spun-bonded non-woven polypropylene fabric. ▶ The fibers were found to be fairly uniform and show a narrow distribution in diameter. ▶ The average diameter was found to be 103 nm and the standard deviation was 20 nm. ▶ The electro-dialytic separation of cations (Na + from Mg 2+ or Ca 2+) was achieved using ESPEEK membrane. ▶ ESPEEK membrane may be the promising candidate for electro-dialytic selective separation of ions from their mixture. We reported fabrication of electrospun nano-fibrous ion-exchange membrane (IEM) composed of sulfonated poly(ether ether ketone) (SPEEK). Prepared membrane was employed for electro-dialytic separation of Na + from Mg 2+ or Ca 2+, which is an urgent problem for the production potable water from brackish water and chlor-alkali industries. Nano-fibrous membrane was successfully fabricated onto spun-bonded non-woven polypropylene fabric. Electrospun SPEEK (ESPEEK) and SPEEK thin film membrane's suitability, for the electro-dialytic separation of cations, was assessed by their conductivity measurements under different electrolytic environment using electrochemical impedance spectroscopy. Counter-ion transport number and membrane permselectivity were strongly depended on the nature of counter-ions. ESPEEK membrane showed very low selectivity (about negligible) for Mg 2+ and Ca 2+, because formation of nano-fibrous pore or channels, which restricted the migration of bi-valent cations. Additionally, very low flux and electro-transport efficiency for bi-valent cations in compare with Na + across ESPEEK membrane, suggested its possible application for electro-driven separation of mono-valent and bi-valent electrolytes. Electrospun nano-fibrous IEMs may be the promising candidate for electro-dialytic selective separation of ions depending on their charge and hydrated ionic size