Target mass correction on the 3He polarized structure function

Target mass correction (TMC) is employed to amend the polarized helium structure functions, ³He . The structure function can be obtained via the convolution of the light cone momentum distribution with the polarized structure of the proton and neutron. The calculation of the polarized structure function of the nucleon is based on the constituent quark model. The analytical result for ³He polarized structure function at low values of Q² is not in good agreement with the available experimental data. The reliability of calculations is increased using TMC effect. New comparison confirms a better agreement with the experimental data.     

Essential oil composition of Nepeta satureioides from Iran

The essential oil of Nepeta satureioides Boiss. from Iran was isolated by hydrodistillation in yield of 0.06% (w/w). The chemical composition of the essential oil was analyzed by GC and GC-MS. Forty-five compounds accounting for 97.4% of the total oil were identified. The major components were linalool (23.8%), (Z,E)-farnesol (14.7%), linalyl acetate (11.1%), β-caryophyllene (6.6%), lavandulol acetate (6.6%), caryophyllene oxide (6.4%), and (Z)-β-farnesene (3.4%). Oxygenated terpenoids were the main group of compounds. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 144–145, March–April, 2006.     

Optical buffer performance enhancement using Particle Swarm Optimization in Ring-Shape-Hole Photonic Crystal Waveguide

Ring-Shape-Hole Photonic Crystal Waveguides (RSHPCW) is a popular structure in designing optical buffers attracted many attentions recently. There are some parameters such as the radii of holes and pillars next to the defect that have significant effects on slow light properties. Consequently, one of the promising methods for effectively slowing the light speed down and controlling dispersion is to optimize these parameters, which is the motivation of this study. Particle Swarm Optimization (PSO) algorithm is one of the best proposed heuristic optimization algorithms in Artificial Intelligence applied to many engineering problem. In this work, this algorithm is employed to find the best values of the aforementioned radii for maximizing Normalized Delay-Bandwidth Product (NDBP) of RSHPCW structure as the first systematic optimizer. Calculation results show that there are 34% and 41% improvement in NDBP and bandwidth compared to the previous works, very substantial achievements in this area.     

A novel method for sulfonation of aromatic rings with silica sulfuric acid

Direct and chemoselective sulfonation of aromatic compounds with silica sulfuric acid in 1,2-dichloeoethane or under solvent-free conditions.     

Solvent‐free Oxidation of Alcohols by Silica Sulfuric Acid/Sodium Dichromate Dihydrate or Potassium Permanganate/Wet SiO2 System

A combination of silica sulfuric acid and sodium dichromate dihydrate or potassium permanganate in the presence of wet SiO₂ was used as an effective oxidizing agent for oxidation of alcohols to their corresponding aldehydes or ketones in solvent free conditions.     

Essential oil variation of Salvia officinalis aerial parts during its phenological cycle

In this paper the variation in the quantity and quality of the essential oil of Salvia officinalis during its life cycle stages is reported. The oils were obtained by hydrodistillation of air-dried samples. The yield of essential oil (w/w %) in different stages was in the order: floral budding (0.9%) > vegetative (0.7%) > flowering (0.5%) > immature fruit (0.4%) > ripen fruit (0.2%). The essential oils were analyzed by GC and GC-MS. In total, 36, 41, 40, 38, and 41 constituents were identified and quantified in the subsequent stages, respectively. Oxygenated monoterpenes were the main group of compounds in the fruiting set (56.9%), vegetative (48.5%), flowering (47.7%), and floral budding (45.3%) stage. 1,8-cineole as one of the major constituents of all samples was lower in the vegetative stage and gradually increased in subsequent harvesting times to reach a maximum in flowering and then decreased in the fruiting set. In contrast, the globulol content was higher in the first stage and decreased drastically during fruit maturation. Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 16–19, January–February, 2006.     

尿酸和叶酸存在下改性碳纳米管糊电极上多巴胺电催化氧化MohammadMazloum-Ardakani,MahboobeAbolhasani,Bibi-FatemehMirjalili,MohammadAliSheikh-Mohseni,AfsanehDehghani-Firouzabadi,AlirezaKhoshroo简

A chemically modified carbon paste electrode (CPE), consisting of 2,2''-[(1E)-(1,2-phenylenebis(azanylylidene)] bis(methanylylidene)]bis(benzene-1,4-diol) (PBD) and multiwalled carbon nanotubes (CNTs), was used to study the electrocatalytic oxidation of dopamine using cyclic voltammetry, chronoamperometry, and differential pulse voltammetry (DPV). First, the electrochemical behavior of the modified electrode was investigated in buffer solution. Then the diffusion coefficient, electrocatalytic rate constant, and electron-transfer coefficient for dopamine oxidation at the surface of the PBD-modified CNT paste electrode were determined using electrochemical approaches. It was found that under optimum conditions (pH = 7.0), the oxidation of dopamine at the surface of such an electrode occurred at about 200 mV, lower than that of an unmodified CPE. DPV of dopamine at the modified electrode exhibited two linear dynamic ranges, with a detection limit of 1.0 μmol/L. Finally, DPV was used successfully for the simultaneous determination of dopamine, uric acid, and folic acid at the modified electrode, and detection limits of 1.0, 1.2, and 2.7 μmol/L were obtained for dopamine, uric acid, and folic acid, respectively. This method was also used for the determination of dopamine in a pharmaceutical preparation using the standard addition method.     

Target mass correction on the 3He polarized structure function

The diffusion-effusion model has been used to analyse the release and yields of Fr and Cs isotopes from uranium carbide targets of very different thicknesses (6.3 and 148 g/cm²) bombarded by a 1 GeV proton beam. Release curves of several isotopes of the same element and production efficiency versus decay half-life are well fitted with the same set of parameters. Comparison of efficiencies for neutron-rich and neutron-deficient Cs isotopes enables separation of the contributions from the primary (p + ²³⁸U) and secondary (n + ²³⁸U) reactions to the production of neutron-rich Cs isotopes. A rather simple calculation of the neutron contribution describes these data fairly well. The FLUKA code describes the primary and secondary-reaction contributions to the Cs isotopes production efficiencies for different targets quite well.     

Using graphene/TiO2 nanocomposite as a new route for preparation of electroconductive,self-cleaning,antibacterial and antifungal cotton fabric without toxicity

A novel and efficient process is reported for fabrication of electroconductive, self-cleaning, antibacterial and antifungal cellulose textiles using a graphene/titanium dioxide nanocomposite. Cotton fabric was loaded with graphene oxide using a simple dipping coating method. The graphene oxide-coated cotton fabrics were then immersed in TiCl₃ aqueous solution as both a reducing agent and a precursor to yield a fabric coated with graphene/titanium dioxide nanocomposite. The crystal phase, morphology, microstructure and other physicochemical properties of the as-prepared samples were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy and UV-Vis reflectance spectroscopy. Electrical resistance, self-cleaning performance, antimicrobial activity and cytotoxicity of treated fabrics were also assessed. The electrical conductivity of the graphene/titanium dioxide nanocomposite-coated fabrics was improved significantly by the presence of graphene on the surface of cotton fabrics. The self-cleaning efficiency of the treated fabrics was tested by degradation of methylene blue in aqueous solution under UV and sunlight irradiations. The results indicated that the decomposition rates of methylene blue were improved by the addition of graphene to the TiO₂ treatment on fabrics. Moreover, the graphene/titanium dioxide nanocomposite-coated cotton samples had negligible toxicity and possessed excellent antimicrobial activity.     

Oxidative Removal of Acetal Protection by the Action of KHSO5 and AlCl3 under Mild Heterogeneous Conditions

Russian Journal of Organic Chemistry -