methyl ester is a liquid biofuel obtained by chemical processes from vegetable oils or animal fats and an alcohol that can be used in diesel engines, alone or blended with diesel oil.in this study , the transesterification of sunflower oil with methanol was studied using NaOH as catalyst.the dependence of the conversion of sonflower oil on the reactions variables as methyl ester preparation, Separation of methyl ester from by-products, methyl ester purification, Effect of Molar ratio of Methanol to oil on Transesterification, Effect of Catalyst Concentration on Transesterification, was performed.The limited fossil fuel resources along with the need to reduce Green House Gas emissions were a major impulse to the development of alternative fuels. As a result, increased attention has been given to biofuels, such as biodiesel, that can be used as an alternative fuel in compression–ignition engines. Its production from renewable resources, such as vegetable oils and animal fats, makes it biodegradable and non-toxic; also, it contributes to the reduction of CO2 emissions, because it comprises a closed carbon cycle

Sample preparation is an important step in chemical analysis. The present article gives an overview about the Stir bar sorptive extraction (SBSE) as a technique for sample preparation for chromatographic analysis. Stir bar extraction, desorption steps and optimization of the extraction conditions like pH, extraction time, addition of an inert salt, addition of an organic modifier and stirring speed have been discussed. Extraction mechanism, advantages, disadvantages and some applications in water, environmental, pharmaceutical and food analysis have been also discussed. The application of SBSE can be considered as an attractive alternative to classical extraction methods by reducing the consumption of and exposure to the solvent, disposal cost, and extraction time.

In this work, a novel and extra sensitive method for on-line continues monitoring of Clarithromycin in whole blood sample was introduced based on coupling of electro-membrane extraction (EME) and stripping fast Fourier transform continuous cyclic voltammetry (SFFTCCV). In this method, the potential waveform was continuously applied on a Poly(L-Aspartic Acid)/Graphite Oxide/Pristine Graphene/Glassy Carbon Electrode and the electrode response was obtained by detracting the background current and in the following integrating the current in the specific potential range of oxidation of the analyte. This method was performed by applying a DC potential and migration of Clarithromycin from the sample solution into a layer of 4-methyl-2-pentanol that is immobilized in the pores of the sheet membrane and then migration into the acceptor solution. A low and valuable detection limit of 1.0 ng ml-1 and quantification limit of 6.0 ng ml-1 are considered as a part of the sensible results of this experiment. Furthermore, an efficient linearity in the range of 6.0-1000 ng ml-1 were found.

A superhydrophobic (SH) surface is a nanoscopic coating layer that repels water. Due to extreme water repellency has properties such as self-cleaning and anti-icing. In this context, access to bulk water repellency, cost effective, durability against acids and bases, fluorine free and catalyst free synthesis of a superhydrophobic coating, has been remaining an elusive goal. We demonstrated a unique class of modification of silica nanoparticle with coating by grafting short and long normal chain alcohols on silica nanoparticles surface by a facile two-step method and without catalyst. The modified nanoparticles showed very well SH property. This kind of coating and modification, hitherto undisclosed, is expected to be a breakthrough in the field non fluorine and cost effective industrial SH coatings.

The measurements of copper sulphate conductance have happened in binary mixed solvent with ethanol in different mass fraction 0%, 20% and 40% (W/W) (EtOH-H2O) at four different temperatures from 298.15 to 313.15o K (with a step of 5o K). The experimental data obtained by using the Fuoss-Shedlovsky extrapolation technique. All thermodynamic parameters for association were calculated. This parameters such as molar conductance (Λm), limiting molar conductance (Λ0), Walden product (Λ0 η0), ion-pair association constant (KA), the activation energy for the transport process (Ea) and also the standerd thermodynamic prameters for association (∆GoA, ∆HoA and ∆SoA). Although we studied the effect of hydrogen bond formation in solution. The results estimated show that the association constant was increased with increasing temperature while the molar conductance and the limiting molar conductance values were decreased. Furthermore, all the association constant values were increased indicating that the association process is endothermic.

This review examines high performing energy storage devices for high-power applications including heavy electric vehicles, energy-efficient cargo ships and locomotives, aerospace and stationary grid system. Such devices require systematic design and fabrication of composite nanostructured carbon-based material and conductive polymers. Electrochemical capacitors based on nanostructured carbon can complement or replace batteries in electrical energy storage and harvesting applications, when high power delivery or uptake is needed. Composite device of pseudo-capacitive polymeric materials and nanostructured carbon with the latest generation of nanostructured lithium electrodes has brought the energy density of electrochemical capacitors closer to that of batteries without compromising its specific power density, high capacitance and lifetime cycling stability. Energy storage devices’ widespread applications in industrial, hybrid electric vehicles and commodity electronics could be facilitated through careful selection of electrolyte-electrode system. Good understanding of charging mechanism is key to improving device’s performance. Charging mechanism includes sequential ion desolations in pores smaller than the solvated ions through ion exchange or ion adsorption. This leads to higher capacitance for such storage devices. This has opened the door to designing advanced high-energy density devices with fast charging and discharging times using a variety of electrolytes and nanostructured carbon-polymer composite.