Trace analysis of N-formylmorpholine in hydrocarbons and water by gas-liquid chromatography

Summary N-Formylmorpholine, which is a solvent used in the extraction of benzene, toluene and xylenes extraction from petroleum feedstocks, is determined in trace amounts in water and in aromatic hydrocarbons by gas-liquid chromatography using two stationary phases. Traces of N-formylmorpholine in hydrocarbons was determined on a column packed with 2.3% Bentone 34+4.6% DEGA on Chromosorb W AW treated with 1% KOH. Traces of N-formylmorpholine in water was determined on 20% SE-30 on Chromosorb W AW. The developed methods were examined and proved to give quantitative results.     

Synthesis,characterization, electrochemical behaviour and catalytic activity of manganese(II) complexes with linear and tripodal tetradentate ligands derived from Schiff bases

New manganese(II) complexes, [Mn(H₂L)(H₂O)₂]Cl₂· xH₂O, with linear and tripodal tetradentate ligands have been synthesized and characterized by elemental analysis, molar conductance, i.r. spectra, magnetic measurements and electronic and e.s.r. spectra. The data show that the ligands are neutral and coordinate to manganese in a tetradentate manner; the other axial sites are occupied by the water molecules. Magnetic and e.s.r. data show that manganese(II) adopts a high-spin configuration in the complexes. The electrochemical behaviour of the complexes, determined by cyclic voltammetry, shows that the chelate structure, ligand geometry and electron donating effect of the ligand substituents are among the factors influencing the redox potentials of the complexes. In addition, we note that linear ligands stabilize the manganese(III) state to a greater extent than tripodal ligands and their complexes vigorously catalyse the disproportionation of hydrogen peroxide in the presence of added imidazole.     

Dose distribution of gamma radiation in a new geometric configuration of a standard carton date package and its experimental application for disinfestation of packed dates

A new geometrical configuration composed of three standard carton boxes (SCBs) full with polyethylene bags (PBs), where each bag contains 1 kg of date, was placed on a single turntable of Gammabeam-650 and irradiated with low doses. The mean “radiation absorbed dose” for disinfestation of this geometrical unit at 15 equally distributed positions (Fricke dosimeters) inside 3 SCBs put on a single turntable was calculated to be 0.46 ± 0.20 kGy and dose uniformity ratio (U) = 1.0019/0.2500 = 4.00. The development and genetic tests carried out on insects found in the PBs 1–2 days after irradiation resulted in that all insects were completely sterile and died within a short period of time. No sign of any reinfestation was recorded at all in the treated packages even after 30 days of storage in an insectory. Apparently the prevention of insects from invading and/or penetrating the date packages is due mainly to the new combination of standard carton boxes that are widely used for commercial purposes and hermetically heat-sealed polyethylene bags of dates in addition to the entire prevention of reproduction induced by the “low” doses of γ radiation. Therefore, by using similar geometrical configuration, 18 big standard carton date packages can be simultaneously disinfected, using the same range of doses or so, by utilizing all the 6 turntables inside the radiation chamber of the Gammabeam-650 irradiation facility.     

Enhancement of Congo red dye removal efficiency using Mg-Fe-layered double hydroxide

Research on Chemical Intermediates - In this study, Mg-Fe(II)-Al-layered double hydroxide with different molar ratios Fe/Al (Mg0.80-Fe0.14-Al0.06-LDHs and Mg0.80-Fe0.20-Al0.00-LDHs) was prepared...     

Chemical characteristics of aerosol insecticide deposition in indoor surfaces

We investigated the deposition rate of aerosol insecticide on through woollen surfaces inside a test chamber. Compared to floor surface, the deposition rate of aerosol insecticide active ingredient on table of 1 m high was up to 2.07 times for piperonyl butoxide, 1.64 times for tetramethrin and 2.95 times for permethrin represented by 0.51, 0.37 and 0.23 μg cm^?2 for the three molecules, respectively. Application of the household used cleaning to the woollen table surface decrease these concentrations by 61.32%, 45.01% and 59.80% for the three pesticides respectively, this cleaning procedure still not efficient for the floor surfaces. Moreover, indoor conditions permit the removal of 46.42%, 21.92% and 14.35% of the table surface deposition rate after one week, for the three pesticides, respectively. These conditions ensure the removal of only 28.72%, 20.69% and 24.05% of the three deposit molecules respectively on floor surface.     

Eutectic crystallization and hydrogen bonding interactions in polymer/surfactant blends

The unusual eutectic crystallization behavior in the poly(ε‐caprolactone) (PCL) and 3‐pentadecylphonel (PDP) binary blends was investigated by differential scanning calorimetry and Fourier transform infrared (FTIR) spectroscopy. A eutectic system was found with the eutectic composition at 60 wt % PDP and the eutectic melting temperature at 35 °C. The melting process of the blend at the eutectic composition was studied by in situ FTIR. The concurrence of the melting of PCL and PDP crystallites and the sequential formation of hydrogen bonding interaction between PDP molecules and PCL chains were traced. It was also found that a further increase in temperature above the eutectic melting temperature would impair the hydrogen bonding and increase the content of nonassociated phenol hydroxyl group. The semicrystalline morphology of blends affected by the composition was also investigated. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1015–1023, 2009     

Solar thermochemical reactionsⅢ:A convenient one-pot synthesis of 1,2,4,5-tetrasubstituted imidazoles catalyzed by high surface area SiO_2 and induced by solar thermal energy

A simple,convenient and efficient method for the synthesis of 1,2,4,5-tetrasubstituted imidazole derivatives using benzoin,an aromatic aldehyde,an aromatic amine in the presence of ammonium acetate catalyzed by high surface area SiO_2 and induced by free solar thermal energy was reported.     

Gas chromatography active ingredient control of aerosol insecticide from Algerian market

Household insecticide products are common and a popular mode of personal protection against household insect pests in all parts of the world. A chromatographic method for the control of aerosol insecticide active ingredient content was developed to be simple and rapid for the inspection of the numerous products for professional and private uses proposed in the Algerian market. Throughout, the most sold aerosol insecticides only two over eight were fair to the label declaration. However, the product labels need the addition of some details, like the active ingredients concentrations.     

Peristaltic transport and heat transfer of a MHD Newtonian fluid with variable viscosity

The influence of temperature‐dependent viscosity and magnetic field on the peristaltic flow of an incompressible, viscous Newtonian fluid is investigated. The governing equations are derived under the assumptions of long wavelength approximation. A regular perturbation expansion method is used to obtain the analytical solutions for the velocity and temperature fields. The expressions for the pressure rise, friction force and the relation between the flow rate and pressure gradient are obtain. In addition to analytical solutions, numerical results are also computed and compared with the analytical results with good agreement. The results are plotted for different values of variable viscosity parameter β, Hartmann number M, and amplitude ratio ?. It is found that the pressure rise decreases as the viscosity parameter β increases and it increases as the Hartmann number M increases. Finally, the maximum pressure rise (σ=0) increases as M increases and β decreases. Copyright © 2009 John Wiley & Sons, Ltd.