Adsorption of diazinon and fenitothion on MCM-41 and MCM-48 mesoporous silicas from non-polar solvent

The adsorption of two common organophosphorus pesticides, diethoxy-[(2-isopropyl-6-methyl-4-pyrimidinyl)oxy]-thioxophosphorane (diazinon) and dimethoxy-(3-methyl-4-nitrophenoxy)-thioxophosphorane (fenitrothion), by MCM-41 and MCM-48 mesoporous silicas at room temperature was investigated. UVvis and IR spectroscopy, small-angle X-ray diffraction, and the specific surface area analysis (S _BET) were used to study the adsorption behavior of diazinon and fenitrothion. The results show that the MCM-41 and MCM-48 mesoporous silicas adsorb diazinon more efficiently than fenitrothion. The extraction of adsorbed materials from the adsorbents with polar solvents and subsequent analysis by ³¹P NMR showed that the adsorption of diazinon and fenitrothion on mesoporous silicas is destructive and non-destructive, respectively. Nitrogen adsorption measurements showed that the specific surface area of both silicas decreases after the adsorption of pesticides, and the larger effect is observed for diazinon. The article is published in the original.     

Development and Validation of a Novel Gradient LC Method for Simultaneous Determination of Isoniazid and Acetylisoniazid in Human Plasma

The goal of this study was to develop and validate a new gradient high-performance liquid chromatography method for the simultaneous determination of isoniazid (INH) and acetylisoniazid (Ac-INH) in human plasma samples. A C18 reversed-phase column was employed for separation followed by UV detection at 266 nm. The calibration involved the use of five concentration levels ranging from 1 to 20 μg mL^?1 for both analytes. The developed method was validated using ICH guidelines. The calibration curve was found to be linear with correlation coefficient values (r ²) above 0.9991 and the highest RSD% values for intra-day assays were found to be 6.34 and 2.57% for INH and Ac-INH, respectively. The highest RSD% values for inter-day assays were 9.31 and 10.17% for INH and Ac-INH, respectively. LOD was calculated to be 0.1 and 0.15 μg mL^?1 for INH and Ac-INH, respectively. LOQ was calculated to be 0.33 and 0.5 μg mL^?1 for INH and Ac-INH, respectively.     

Analysis of a Low Cost and Low Complexity Adaptive Transmission Scheme for Massive MIMO Systems with Interference

Wireless Personal Communications - This paper evaluates a low-complexity Multiuser Adaptive Modulation (MAM) scheme for an uplink massive multiple-input and multiple-output (MIMO) systems with...     

Character inner amenability for semigroups

Semigroup Forum - Let $$varphi $$ be a character on a semigroup S. We introduce the notions of $$varphi $$-inner amenability and character inner amenability for S. We study the relation between...