Fatty acid composition of lipids in pot marigold (Calendula officinalis L.) seed genotypes

Background

The process of thermal decomposition of dichloromethane (DCM) and chlorobenzene (MCB) during the combustion in an inert, bubbling fluidized bed, supported by LPG as auxiliary fuel, have been studied. The concentration profiles of C₆H₅CI, CH₂Cl₂, CO₂, CO, NO_x, COCl₂, CHCl₃, CH₃Cl, C₂H₂, C₆H₆, CH₄ in the flue gases were specified versus mean bed temperature.

Results

The role of preheating of gaseous mixture in fluidized bed prior to its ignition inside bubbles was identified as important factor for increase the degree of conversion of DCM and MCB in low bed temperature, in comparison to similar process in the tubular reactor.

Conclusions

Taking into account possible combustion mechanisms, it was identified that autoignition in bubbles rather than flame propagation between bubbles is needed to achieve complete destruction of DCM and MCB. These condition occurs above 900°C causing the degree of conversion of chlorine compounds of 92-100%.     

Hydrogenation of chloronitrobenzenes over Pd and Pt catalysts supported on cationic resins

Liquid phase hydrogenation of chloronitrobenzene isomers (x-CNB x = 2, 3, 4) to the corresponding chloroanilines (x-CAN) at mild reaction conditions (0.6 MPa, 25°C, diethyl ether-methanol as solvents) over palladium and platinum catalysts containing 1 mass % of metal on trimethylammonium functionalized poly{styrene-co-divinylbenzene} (Dowex-D) was studied. The average selectivities to x-CAN over Pd/D-Cl and Pd/D-OH catalysts were 72 % and 42 %, respectively, at the x-CNB conversion of about 80 %. The average selectivities of 81 % and 84 % were achieved using Pt/D-Cl and Pt/D-OH, respectively, at the x-CNB conversion of approximately 90 %, whereas the average starting reaction rates were 1.2 × 10^?3 mol g^?1 s^?1 and 2.6 × 10^?3 mol g^?1 s^?1 (hydrogen consumption rate per mass of platinum), respectively. Under similar reaction conditions, using palladium catalysts supported on a resin with anionic groups anchored to polymeric chains at the average reaction rate equal to 3.8 × 10^?3 mol g^?1 s^?1 (hydrogen consumption rate per mass of palladium), the selectivities from 85 % (2-CAN and 3-CAN) to 95 % (4-CAN) were achieved (Kratky et al., 2002).     

A Novel Strategy for Quantifying Clopidogrel Using Square‐wave Voltammetry and a Boron‐doped Diamond Film

The voltammetric behavior of clopidogrel bisulfate (CLO), an antiplatelet agent, was investigated for the first time in the literature on a cathodically pretreated boron‐doped diamond electrode (CP‐BDDE) using cyclic (CV) and square‐wave voltammetry (SWV). It was observed an anodic peak for CLO, suitable for analytical purposes, at about 1.15 V (vs. Ag/AgCl (3.0 mol L^?1 KCl)) by CV in Britton‐Robinson buffer solution (pH 5.0). On the physical‐chemical characterization of the interface phenomena, it was proved that electrode reaction of the analyte was controlled by a diffusion process. At optimized square‐wave parameters (pulse amplitude of 60 mV, frequency of 30 Hz and scan increment of 3 mV), the obtained analytical curve was linear for the CLO concentration range from 0.60 to 60.0 μmol L^?1, with a detection limit of 0.60 μmol L^?1. The simple, rapid and greener analytical method, based on CP‐BDDE electrochemical sensor, was successfully applied in real samples (pharmaceuticals and urine).     

Thermal decomposition,kinetic study and evolved gas analysis of 1,3,5-triazine-2,4,6-triamine

The thermo-physical properties for four rock types (granite, granodiorite, gabbro, and garnet amphibolite) from room temperature to 1,173 K were investigated. Thermal diffusivity and specific heat capacity were measured using the laser-flash technique and heat flux differential scanning calorimetry, respectively. Combined with the density data, rock thermal conductivities were calculated. Rock thermal diffusivity and conductivity decrease as the temperature increases and approach a constant value at high temperatures. At room temperature, the measured thermal conductivity is consistently near or lower than the calculated conductivity using the mineral series model, which suggests that real thermal conduction is more complicated than is depicted in the model. Therefore, in situ measurement remains the best method for accurately obtaining thermal conductivity for rocks.     

The standard molar enthalpies of formation of chromone-3-carboxylic acid, 6-methylchromone-2-carboxylic acid,and 6-methyl-4-chromanone determined by micro-combustion calorimetry

The energies of combustion of chromone-3-carboxylic acid (C3CA), 6-methylchromone-2-carboxylic acid (6MCC), and 6-methyl-4-chromanone (6M4C) were determined using an isoperibolic micro-combustion calorimeter. The calorimeter used in the present work has been assembled, calibrated, and tested in our laboratory with the desired results. Prior to the measurement of the energies of combustion, the purities, heat capacities (C _p), fusion temperatures (T _fus), and enthalpies of melting (Δ_fus H) for each compound were determined by differential scanning calorimetry. The values of the energies of combustion were used to derive standard molar enthalpies of combustion ( \( \Delta _{{\text{c}}} H_{{\text{m}}}^{\circ } \) ) and standard molar enthalpies of formation ( \( \Delta _{{\text{f}}} H_{{\text{m}}}^{\circ } \) ) in the crystalline phase at T = 298.15 K. The values found for the \( \Delta _{{\text{f}}} H_{{\text{m}}}^{\circ } \) of C3CA, 6MCC, and 6M4C were ?(619.5 ± 2.6), ?(656.2 ± 2.2), and ?(308.9 ± 3.0) kJ mol^?1, respectively.     

Thermal degradation of B-group vitamins: B1, B2 and B6

The thermal behaviour of vitamins B₁, B₂ and B₆ under non-isothermal conditions and dynamic air atmosphere was studied. According to our study, it was determined that the most stable compound is vitamin B₂. A kinetic analysis of the thermodegradation process using four different data processing methods (Friedman, Flynn–Wall–Ozawa, Kissinger–Akahira–Sunose and modified NPK) was performed. The NPK was the only method that made it possible to evaluate the contribution to the reaction rate of the temperature and conversion, respectively. The results obtained from kinetic analysis were corroborated with the molecular architecture of the studied compounds.     

Character tables of p-groups with derived subgroup of prime order II

Two character tables of finite groups are isomorphic if there exist a bijection for the irreducible characters and a bijection for the conjugacy classes that preserve all the character values. In this paper we classify up to isomorphism the character tables of p-groups with derived subgroup of prime order via a combinatorial object independent of the prime p.     

Semiempirical evaluation for proton affinities of phosphorus compounds

We here report the AM 1 and PM 3 evaluation of proton affinities for phosphorus compounds. The substituent effects, the preferred site of protonation, and the geometry changes produced upon protonation are discussed in terms of the present semiempirical calculations that are compared with experimental data and previous ab initio results. © 1993 John Wiley & Sons, Inc.     

Synthesis of methyl derivatives of linear and angular thienocoumarins and thiopyranocoumarins

New linear and angular thienocoumarins and thiopyranocoumarins were synthesized. The key intermediates were appropriate methyl derivatives of 7-mercaptocoumarin, which were condensed with chloro-ketones or propargyl chloride. Thioethers were cyclized under various conditions in order to determine which methods produced the best yields of the desired thienocoumarins 15, 16, 17, 18, 22, 23, 24, 27 and thiopyranocoumarins 28 and 29 .     

Multispectrum analysis of CH4 from 4100 to 4635 cm: 1. Self-broadening coefficients (widths and shifts)

The Lorentz self-broadening (halfwidths) and self-induced pressure-shift coefficients were measured for the first time in the octad region of methane. All spectra were recorded at 0.011 cm⁻¹ resolution using the McMath-Pierce Fourier transform spectrometer located at the National Solar Observatory on Kitt Peak, Arizona. ¹²C-enriched CH₄ gas samples at room temperature were used, and high signal-to-noise ratios of 2000:1 were achieved. The multispectrum nonlinear least squares fitting technique enabled us to fit simultaneously a total of 10 high-resolution laboratory absorption spectra consisting of six self-broadened and four air-broadened spectra. In this paper, we report the self-broadened widths and self-induced pressure shift coefficients for 1423 transitions belonging to five bands with a maximum J of 16. The numbers of measurements by bands are: 71 for ν₂ + 2ν₄, 202 for ν₁ + ν₄, 824 for ν₃ + ν₄, 58 for 2ν₂ + ν₄, and 268 for ν₂ + ν₃. The observed widths varied from 0.045 to about 0.090 cm⁻¹ atm⁻¹ at 296 K. The measured pressure-shift coefficients had values extending from about −0.020 to −0.005 cm⁻¹ atm⁻¹ at 298.3 ± 1.2 K. The results obtained for the broadening coefficients in the various bands were compared with each other and with measurements reported in the literature for other methane bands.