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Background: A wide variety of dihydropyrimidins (DHPMs) exhibit pharmacological and biological activities. Herein, an efficient one-pot synthesis of some 3, 4-dihydropyrimidin-2(1H)-one derivatives is reported using Fe3O4 @SiO2–Pr-INH. Objective: Recently, several catalysts have been used to improve the Biginellis-reaction. However, some of these catalysts have imperfections. Herein, a convenient method for the synthesis of 3, 4-dihydropyrimidin- 2(1H)-ones and their sulfur derivatives using Fe3O4 @SiO2–Pr-INH is reported. Materials and Methods: Firstly, the catalyst was synthesized through a simple four-step method. The Fe3O4 MNPs were synthesized using the chemical co-precipitation method, coated with a layer of silica using TEOS, and then functionalized with CPTMS. Subsequently, a nucleophilic substitution of Cl by isoniazid resulted in the formation of the magnetic Fe3O4@SiO2–Pr-INH. After the preparation and characterization of Fe3O4@SiO2–Pr-INH, its catalytic activity was studied in the synthesis of 3, 4-dihydropyrimidin-2(1H)-one derivatives. Following the optimization of the reaction conditions, several 3, 4-dihydropyrimidin-2(1H)-one derivatives were synthesized by the reaction of ethyl acetoacetate or acetylacetone, thiourea or urea and aromatic aldehydes at 80 °C under solvent-free conditions. Results: Isoniazid-functionalized Fe3O4 magnetic nanoparticles (Fe3O4@SiO2–Pr-INH) were prepared using Fe3O4 with silica layer and their surface was modified with isoniazid. They were characterized successfully by infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy and were used for the synthesis of some 3, 4-dihydropyrimidin-2(1H)-one derivatives as catalysts. Aromatic aldehydes with electron-donating or electron-withdrawing groups afforded 3, 4- dihydropyrimidin-2(1H)-ones and their sulfur derivatives in good to excellent yields in short reaction times. Conclusion: Isoniazid-functionalized Fe3O4 magnetic nanoparticles (Fe3O4@SiO2–Pr-INH) were used as an efficient catalyst for Biginelli-type synthesis of 3, 4-dihydropyrimidin-2(1H)-ones and 3, 4-dihydropyrimidin- 2(1H)-thiones in good to excellent yields and short reaction times. It is noteworthy that this method has several advantages such as simple experimental procedures, the absence of solvent, environmentally benign process, stability and reusability of the catalyst.

In this study, tri-layer fabrics for surgical gown applications were developed using polypropylene spunbond, polypropylene melt-blown and polyester/rayon spunlace (hydro-entangled) nonwoven layers ...

Background: Medications induced QT prolongation could cause ventricular arrhythmia, torsade de pointes, and death. Objective: The purpose of this study was to evaluate the magnitude of QTc interval prolongation as a result of levofloxacin treatment in patients admitted to cardiology wards. Methods: This was a cross-sectional study conducted in the coronary care units and general wards of the Imam Ali Heart Hospital in Kermanshah, Iran. The QTc interval was determined at baseline and after 72 hours of levofloxacin administration. Changes in the QTc interval before and after the levofloxacin prescription were determined. Results: The mean age of recruited patients was 63.26 ± 14.56 years. More than 80% of patients who received levofloxacin experienced QTc prolongation. The QTc interval was increased significantly after levofloxacin administration (15.68 ± 26.84 milliseconds) (p Conclusion: Treatment with levofloxacin in patients with heart disease increases the risk of QT prolongation.

日本語とペルシア語においては、身体語彙を含む慣用句がかなり高い比重を占めている。本稿では、両言語に共通し、頻度のかなり多い句例として見られる「手」と「دست/dast/手」の慣用句を分析し、異同を考察する。具体的には日本語ではメタファーやメトニミーとペルシア語では「مجاز مرسل/ majāz-e morsal/メトニミー」「استعاره/este’āre/メタファー」「کنایه/kenāye/メタファー」などの手法を用いて、意味拡張のプロセスの究明を目指す。

Diazinon is an important organophosphorus pesticide with extensive use, which is considered to be a major health hazard for humans due to its adverse effects on cholinesterase activity and central nervous system. The entry of diazinon into water resources affects a wide range of non-target organisms, which highlights the importance of its removal from water resources. The present study aimed to synthesize and use WO3 doped ZnO nanocatalyst to degrade diazinon. Zinc oxide nanoparticles were synthesized using the hydrothermal method and doped with 0.5%, 1%, and 2% M tungsten oxide. Moreover, the effects of dopant percentage, pH, the initial concentration of diazinon, nanoparticle dosage, and contact time were investigated. The results of EDS revealed that W was doped into ZnO structure. The maximum diazinon degradation (99%) was obtained using 10 mg/cm−2 2% WO3 doped ZnO, 10 mg/l diazinon, neutral pH value and contact time of 180 min. Removal efficiency was decreased by increasing pH and initial diazinon concentration. The experimental kinetic data followed the pseudo-first order model. The reaction rate constant (kobs) was decreased from 0.0205 to 0.0034 1/min with increasing initial diazinon concentration from 10 to 200 mg/L, respectively. The figures of merit based on electric energy consumption (EEO) indicate that less energy is consumed during the degradation of diazinon in the presence of 2% WO3 doped ZnO compared with other photocatalysts. Therefore, it could be concluded that 2%WO3 doped ZnO is a promising material for photocatalytic degradation of diazinon with high efficiency under optimal condition.

A novel online combustion system was developed for the quantification of metals (Ag, Cd, Cr, Fe, La, Li, Mg, Ni, Pb, Y, Zn, and Zr) in volatile organic solvents such as acetone, methyl isobutyl ketone (MIBK), chloroform, dichloromethane, tetrachloroethane or trichloro-trifluoroethane. After combusting the sample aerosol in a commercial carbon analyzer oven in an oxygen-rich atmosphere, carbon dioxide and remaining oxygen were removed from the gas stream prior to the introduction into an inductively coupled plasma optical emission spectrometer (ICP-OES). The proposed combustion/carbon removal approach allowed stable operation of the ICP even when introducing highly volatile solvents that otherwise would have immediately extinguished the plasma. Analyte signals in halogenated solvents were found to be significantly higher than in non-halogenated ones and non-linear calibration functions were observed for all investigated analytes below 5 mg kg−1. Though a stable operation of the plasma was possible, the analyte signal intensities obtained in water were, depending on the element and the solvent, between 1.5 and 2800 times higher than in halogenated solvents.

An efficient one-pot quantitative procedure for the preparation of hydroxyl naphthalene-1,4-dione derivatives from three-component condensation reaction of aromatic aldehydes, aromatic amines, and 2-hydroxynaphthalene-1,4-dione in the presence of nano copper(II) oxide as catalyst under mild, ambient and solvent-free conditions is described. Simple procedure, high yields, short reaction time and an environmentally benign method are advantages of these protocols. The copper(II) oxide nanoparticles can be recovered and reused several times without loss of its activity.

An efficient one-pot quantitative procedure for the preparation of functionalized benzo[a]pyrano[2,3-c]phenazine derivatives from four-component reaction of 2-hydroxynaphthalene-1,4-dione, o -phenylenediamine, aldehydes, and malononitrile in the presence of nano CuO as the catalyst has been developed. The copper(II) oxide nanoparticles can be recovered and reused several times without loss of its activity.

Synthesis of 12-aryl-12H-indeno[1,2-b]naphtho[3,2-e]pyran-5,11,13-trione derivatives by the three component reaction of 2-hydroxynaphthalene-1,4-dione, aldehydes, and 2H-indene-1,3-dione under solvent-free conditions at 70 °C in the presence of catalytic amount of acidic ionic liquids such as triethylammonium hydrogensulfate ([Et3NH][HSO4]), triethylamine-bonded sulfonic acid ([Et3N–SO3H]Cl), 2-pyrrolidonium hydrogensulfate ([Hnhp][HSO4]), 3-methyl-1-sulfonic acid imidazolium chloride ([Msim]Cl), and 1-methylimidazolium hydrogensulfate ([Hmim][HSO4]) is described. In addition, 13-aryl-indeno[1,2-b]naphtha[1,2-e]pyran-12(13H)-one derivatives from the reaction of β-naphthol, aldehydes, and 2H-indene-1,3-dione under thermal solvent-free conditions in the presence of mentioned catalysts is reported.

The frequency response of a free running RF generator was evaluated for its ability to provide plasma diagnostic information. A small probe coil in the plasma torch housing and a frequency counter were used for frequency measurement. A linear dependence between the RF generator frequency and the flow of a foreign gas (CO 2 , H 2 , He, N 2 —introduced into the central channel of the ICP) was encountered. Moreover, the inductively coupled plasma (ICP) was found to extinguish at a constant, characteristic frequency when the flow of foreign gas was too high, allowing a simple prediction of the maximal tolerable foreign gas flow. Spectroscopic plasma diagnostic techniques (Mg II/Mg I ratio, excitation temperature and rotational temperature) were also investigated but provided little indication of instable plasma conditions due to the addition of foreign gases.

Electrochemical oxidation of several catechols is studied in the presence of 4(6)-aminouracil (3a) and 6-amino-1,3-dimethyl uracil (3b) as nucleophiles in aqueous solution using cyclic voltammetry and controlled-potential coulometry. The results reveal that quinones derived from catechols participate in Michael additions with 3a and 3b to give the corresponding catecholamine derivatives via an electron transfer followed by chemical reaction (EC) mechanistic pathway in good yields and purities.

A simple and efficient method for the selective separation and preconcentration of Ag+ using homogeneous liquid-liquid extraction was developed. Tetraspirocyclohexylcalix[4]pyrrole (TSCC4P) was synthesized and investigated as a suitable selective complexing ligand for Ag+. Zonyl FSA (FSA) was applied as a phase-separator agent under mild pH conditions. Under the optimal conditions ([TSCC4P] = 3.4 x 10(-4) M, [THF] = 25.0% v/v, [FSA] = 1.25% w/v, and pH = 4.5), 5 microg of Ag+ in 6.0 ml aqueous phase could be extracted quantitatively into 20 microl of the sedimented phase. The maximum concentration factor was 300-fold. The limit of detection of the proposed method was 0.005 ng/ml. The reproducibility of the proposed method was at most 3.5%. The influence of the pH, type and volume of the water-miscible organic solvent, concentration of FSA, concentration of the complexing ligand and the effect of different diverse ions on the extraction and determination of Ag+ were investigated. The proposed method was applied to the extraction and determination of Ag+ in different water samples.