Isolation and characterization of ingenol esters from Euphorbia cornigera

Methanolic extract of Euphorbia cornigera Boiss.on HPLC separation yielded three new compounds.Their structures and relative stereochemistry were established through 2D-NMR spectroscopic measurements.     

Line laser-based break sensor that detects light spots on yarns

In this paper, current yarn break sensor systems are investigated and a line laser-based yarn break sensor is proposed. In this proposed sensor system, yarns aligned in the same plane are illuminated with a line light and the light spots on the yarns are detected with a CCD camera, total yarn number is compared with the number of the light spots formed by the line laser on yarns. If the number of the yarns used is greater than the number of the light spots, sensor warns the breaking.Design principles of the line laser-based yarn break sensor are presented. Detection area of the sensor related to the yarn number, yarn thickness and the distances between the yarns is obtained. Equations for calculating the line laser radiation angle and the light spot intensity related to the detection area width and the line laser placement height are obtained.Different placement situations of line laser (transmitter) and the CCD camera (receiver) related to the yarn plane are explained. An experimental setup is developed to test the system and the image of the light spots formed on yarns is obtained. Block diagram of the sensor is given and the operation principle is explained.     

Synthesis and Characterization of <Emphasis Type="Italic">Cis</Emphasis>-[V<Superscript>IV</Superscript>O(pzc)<Subscript>2</Subscript>(H<Subscript>2</Subscript>O)]·2H<Subscript>2</Subscript>O (pzc: 2-pyrazinecarboxylate)

Abstract  

Hydrothermal synthesis and the structural characterization of V(IV) complex of 2-pyrazinecarboxylate (pzc), is reported. The vanadium is in a distorted octahedral environment. Pairs of pyrazine-2-carboxylate ligands are always cis to each other. The pzc ligands do not link adjacent vanadium atom directly. The remainder of the three-dimensional network is completed by intense hydrogen bonding of uncoordinated water molecules to aqua and pzc ligands. Cis-[V^IVO(pzc)₂(H₂O)]·2H₂O, 1, was characterized by means of elemental analysis (CHNS), TGA, FT-IR, manganometric titration, bond valance sum calculations and single crystal X-ray diffraction methods. Crystal data for 1: monoclinic space group P2 ₁ /c and unit-cell parameters are a = 9.1142(5), b = 16.5822(10), c = 12.8936(7) ?, β = 131.625(3)° and Z = 4. To the best of our knowledge, cis-[V^IVO(pzc)₂(H₂O)] is reported without single crystal structure by Eugenio Garribba and his colleagues in year 2006. Herein we complete full characterization of the title complex with single crystal structure and also 1 will be the first reported example of solid vanadium complex of 2-pyrazinecarboxylates involving intense hydrogen bonding.     

Characteristics of grape seed and oil from nine Turkish cultivars

Percentages of crude oil, protein, fibre and ash of grape seeds obtained from Turkish cultivars were of the ranges 5.40-10.79, 5.24-7.54, 17.6-27.1, and 1.2-2.6, respectively. The highest crude oil, crude protein and crude fibre were determined in Siyah pekmezlik, Karadimrit and Antep grape seeds. The energy values of seeds were established to be between 102.28 and 148.07?kcal?g(-1). Potassium and calcium contents of seed samples were found to be at high levels compared to sodium. The seeds contained 686-967?ppm of Na, 2468-3618?ppm of K and 2373-4127?ppm of Ca. The refractive index, relative density, acidity, saponification value, unsaponifiable matter and iodine value of seed oils were determined to be in the ranges 1.474-1.477 [Formula: see text], 0.909-0.934 25/25°C, 0.74-1.24%, 181-197, 0.91-1.66%, and 126-135, respectively. The main fatty acids were of the ranges 60.7-68.5% linoleic, 16.1-23.4% oleic and 8.0-10.2% palmitic. The highest percentages of linoleic acid (68.5%) was determined in Siyah pekmezlik seed oil.     

Antiproliferative, antimicrobial and apoptosis inducing effects of compounds isolated from Inula viscosa

The antiproliferative and antimicrobial effects of thirteen compounds isolated from Inula viscosa (L.) were tested in this study. The antiproliferative activity was tested against three cell lines using the MTT assay. The microdilution method was used to study the antimicrobial activity against two Gram positive bacteria, two Gram negative bacteria and one fungus. The apoptotic activity was determined using a TUNEL colorimetric assay. Scanning electron microscopy was used to study the morphological changes in treated cancer cells and bacteria. Antiproliferative activity was observed in four flavonoids (nepetin, 3,3'-di-O-methylquercetin, hispidulin, and 3-O-methylquercetin). 3,3'-di-O-Methylquercetin and 3-O-methylquercetin showed selective antiproliferative activity against MCF-7 cells, with IC(50) values of 10.11 and 11.23 μg/mL, respectively. Both compounds exert their antiproliferative effect by inducing apoptosis as indicted by the presence of DNA fragmentation, nuclear condensation, and formation of apoptotic bodies in treated cancer cells. The antimicrobial effect of Inula viscosa were also noticed in 3,3'-di-O-methylquercetin and 3-O-methyquercetin that inhibited Bacillus cereus at MIC of 62.5 and 125 μg/mL, respectively. Salmonella typhimurium was inhibited by both compounds at MIC of 125 μg/mL. 3,3'-di-O-Methylquercetin induced damage in bacterial cell walls and cytoplasmic membranes. Methylated quercetins isolated from Inula viscosa have improved anticancer and antimicrobial properties compared with other flavonoids and are promising as potential anticancer and antimicrobial agents.     

Magnetoelectrical properties of W doped ZnO thin films

ZnO thin films were deposited on the Si(100) substrate by rf sputtering using a 99.999% pure commercially bought and a home made target under 100 W power. The home made ZnO target, including 1–2% tungsten, was synthesized via solid state reaction. Thin films were deposited under a flow of 70% argon and 30% O₂ gas mixture followed by post-deposition annealing under 1 Torr oxygen atmosphere. Both deposition and post-deposition annealing were done at 420±1 °C. The structural analyses show that the films were in the [0002] preferred direction and that W atoms are bound to the oxygen atoms by replacing the Zn host atoms. Although no specific change was observed in the magnetic properties as a result of W doping, significant changes in the electrical properties were observed, as determined by the longitudinal and transversal magneto-electrical measurements. It was found that the W impurities induce better insulating properties due to lower carrier concentration and higher resistivity values. On the other hand, the enhanced positive magnetoresistivity and the existence of polarized spin currents, which were not specific for pure ZnO thin films, were observed in W doped ZnO films below 10 K.     

N,N-bond-forming heterocyclization: synthesis of 3-alkoxy-2H-indazoles

A one-step heterocyclization of o-nitrobenzylamines to 3-alkoxy-2H-indazoles is reported. The electronic nature of the nitrophenyl group, the steric and electronic nature of the R1-functionalized benzylic amine, and the nature of the alcoholic solvent affect the efficiency of this heterocyclization reaction (approximately 40-90%).     

Monte Carlo Study of CO-NO Catalytic Surface Reaction Including CO-CO Repulsion

The CO-NO reaction on a catalytic surface is studied by using Langmuir-Hinshclwood thermal mechanism with Monte Carlo computer simulation. In this model, a novel concept of CO CO repulsion is introduced, which has experimental evidence due to the formation of dipoles when these molecules are chemisorbed on the surface. The system is investigated by applying two approaches of NO dissociation. In the first ca.se, NO always decomposes into N and O before adsorption on the surface, In the second case, NO adsorbs on the surface molecularly and then dissociates into N and O if a vacancy is present in its adjacent neighbourhood. The steady state reactive window （i.e. the continuous production of CO2 and N2） is obtained only with the diffusion of N-atoms on the surface, which extends with CO-CO repulsion in the first, case. Itowever, in the second case, reactive window is obtained with CO-CO repulsion alone, The reactive window width in this case is reasonably large. The first-order phase transition is eliminated in both the cases with CO-CO repulsion.     

Influence of temperature on surface tension of three liquid crystal polymers and polyethylene terephtalate

In this work Pressure Volume Temperature (PVT) data for three different liquid crystal polymers (LCPs), namely Vectra A950^® and two LCPs based on 4,4'-dihydroxybiphenyl (PB-n) (where n is the number of methylene units present in the polymer) and polyethylene terephtalate (PET), were obtained for temperatures ranging from 50 to 300°C and pressures ranging from 0.1 to 200 MPa. The experimental data were fitted to the Flory-Orwoll-Vrij equation of state and used to predict the influence of temperature on the surface tension of the four materials studied.

The surface tension of PET was shown to decrease linearly with increasing temperature. The surface tension of both PB-11 (γ_PB-11) and Vectra A950^® (γ_Vectra) decreased linearly with increasing temperature for temperatures corresponding to the nematic phases of the materials. Abnormal behaviour was observed for the surface tension of PB-8 (γ_PB-8): at temperatures just above T_b (the temperature at which the material became birefringent), γ levelled off and then decreased. A clear discontinuity was observed for both γ_PB-8 and γ_PB-11 near the mesophase to isotropic transition. For both PB-8 and PB-11, γ decreased linearly with increasing temperature for temperatures corresponding to the isotropic phases of the materials.     

Rapid and Efficient Microwave‐Assisted Synthesis of Some New Triazol‐3‐one Derivatives

A growing body of literature has shown the effectiveness of using microwaves in chemical reactions. The aim of this study is to demonstrate a rapid and highly efficient synthesis of some new triazol‐3‐ones via microwave heating using a monomode microwave. Compared with the thermal process, the microwave heating induces a dramatic reduction of the reaction time and improvement of the yields. In this study, rapid N‐benzylation and N‐acetylation of triazol‐3‐ones were achieved by microwave irradiation method for the first time. The newly synthesized compounds showed moderate antimicrobial activity against the standard bacterial and fungal organisms tested.