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Biomass derived carbon materials have advantages of cost and availability over other carbon materials. However, handful researches based on biomass derived carbon materials have been conducted to explore the oil–water adsorption potential. In this study, we demonstrated that the egg yolk derived carbon material in the presence of iron nanoparticle can be used as a cost-effective absorbent to oil–water separation. Carbon-sponge composite was prepared by dip coating method and showed high adsorption capacity (from 28 to 87 times its original weight) for broad spectrum of organic solvents and oil. These results show evidence that the egg yolk derived carbon material is suitable candidate for the construction of hydrophobic sponge in large-scale and low-cost for removal of oil contaminants from aqueous medium.

Two novel heterogeneous hybrid catalysts were successfully synthesized using octa-aminopropyl polyhedral oligomeric silsesquioxane hydrochloride salt (OA-POSS) and ionic liquids, followed by immobilization of Cu and Ag nanoparticles. The obtained hybrid catalysts, Cu@POSS-ILs and Ag@POSS-ILs, were characterized using FT-IR, SEM, EDX, TEM, XRD and TGA. Catalytic studies demonstrated that Cu@POSS-ILs was an excellent catalyst for click reaction in aqueous medium. Furthermore, Ag@POSS-ILs was also exhibited to be an active catalyst for 4-nitrophenol (4-NP) reduction. Simple preparation and easy catalysts recovery and recyclability of Cu@POSS-ILs and Ag@POSS-ILs for at least 3 and 6 runs, respectively, without loss of catalytic activity could be considered as important advantageous from catalytic application point of view.

Octavinyl polyhedral oligomeric silsesquioxane (POSS) was polymerized on the surface of Fe3O4 nanoparticles (NPs) and then the NPs were functionalized with carboxylic acid groups using thiol-ene click reactions with thioglycolic acid. The as-prepared Fe3O4@POSS-COOH magnetic hybrid NPs had mesoporous structures with an average particle diameter of 15 nm and a relatively high specific surface area of 447 m2·g−1. Experimental results showed that 4 mg of Fe3O4@POSS-COOH NPs efficiently adsorbed and removed methylene blue from water at 5 min. This is due to the presence of both carboxylic acid and pendant vinyl groups on the Fe3O4@POSS-COOH NPs. These NPs could be easily withdrawn from water within a few seconds under moderate magnetic field and showed high stability in acid and alkaline aqueous mediums.

In this study, a new series of hybrid hydrogels based on poly(N-isopropyl acrylamide-co-itaconic acid) containing octavinyl polyhedral oligomeric silsesquioxane (OV-POSS) nontoxic cross-linker with different feed ratio were fabricated via free radical copolymerization. The resulted hydrogels were characterized by FT-IR, SEM, XRD and TGA analysis. Various parameters such as time, temperature, pH and salt effects were investigated on the swelling as well as dye removal properties of hybrid hydrogels. The adsorption experiments showed that the maximum adsorption capacity accrued at pH 11 for methylene blue. Adsorption kinetics was elucidated by both pseudo-first-order and pseudo-second-order kinetic models under different conditions. Also, adsorption isotherm of the adsorption of methylene blue on poly(NIPAM-co-IA)/POSS8 adsorbent was investigated using Langmuir, Freundlich, Redlich–Peterson and Sips models, in which the experimental data were fitted well with Langmuir, model.

A novel nanosensor based on CdSe quantum dots (QDs) capped with 8-hydroxyqunoline (HQ) was developed for Al3+ ions determination in aqueous solutions. The method is based on the fluorescence enhancement of the HQ functionalized QDs in the presence of Al3+ ions, due to the strong interaction between Al3+ and HQ. Prepared nanosensor exhibited an acceptable selectivity and sensitivity for Al3+ ions in the presence of other metal ions. Plot of Log(I/I0) against Log[Al3+] shows a good linearity in the range of 0.02–3.0 mM, and the method could be used for detection of Al3+ ions concentration in aqueous solutions.

A nanosensor based on p-nitrophenyldiazenylphenyloxadiazole (NDPO) capped CdSe quantum dots (QDs) was developed for Cd2+ ions in aqueous solutions. The nanosensor exhibited a high selectivity for cadmium ions and showed linear correlation with Cd2+ ions concentration in the range of 0.05–1.0 mmol/L. The prepared NDPO capped CdSe QDs were characterized by TEM, SEM, EDX, and FTIR techniques.

In the present study, poly(acrylamide-co-itaconic acid) hybrid nanocomposites were synthesized via free radical copolymerization method. Octavinyl polyhedral oligomeric silsesquioxane (OV-POSS) with different weight ratio (0, 4, 8, 12 and 14 wt%) was utilized as a cross-linker. Dye adsorption properties of the as-prepared hybrid nanocomposites were investigated for crystal violet (CV) elimination from aqueous solution. The effect of various parameters, such as OV-POSS content, adsorbent amount, pH, temperature, contact time and initial dye concentration, on the adsorption of CV was studied. Moreover, adsorption kinetic, isotherm and the thermodynamic of the CV adsorption on the so-called hybrid nanocomposites were studied.

In this investigation, the preparation of novel Halloysite-based chitosan/oxidized starch (Hal/CTS/OSR) Hybrid bionanocomposite hydrogels is described. The obtained hybrid hydrogels were characterized by using FT-IR, SEM, XRD, TGA and DTG techniques. In addition, the efficiency of hydrogels as drug delivery systems was studied. The results demonstrated that depending on experimental parameters, such as the ratio of CTS/OSR, and the type of Hal nanotubes (modified or unmodified), the hydrogel properties can be affected and modulated significantly. 74.3%, 71.2% and 69.45% MTZ release were observed for CTS/OSR/mHal 10, CTS/OSR and CTS/OSR/Hal 10 respectively.

A new method based on CdSe quantum dots (QDs) was developed to detect 185delAG mutation in BRCA1 gene. In this method P2-NH2 strand was covalently attached to QDs possessing carboxylic acid to provide QD-P2, and its emission was studied against other probs. In the presence of cDNA and P1-NH2, emission of QD-P2 was 85% more intense than just pure bare QD-P2. Moreover, new peak appeared in emission spectrum in higher wavelength which could be associated with formation of more organized shrinked aggregates due to connection between QDs by DNA strands. Partial (35%) increase in the intensity of emission in the presence of mDNA was observed, according to the formation of disorganized aggregates and therefore less rigid system, which is attributed to mutation in DNA strands. The generation of organized small and disorganized aggregates in the presence of cDNA and mDNA, respectively, was approved by DLS analysis and zeta potential measurements.

A copper-containing polyoxovanadate nanocluster, [(C2H5)4N]4[V8Cu2O24]∙2H2O (1), was synthesized through reaction between the Cu(NO3)2∙3H2O and [(C2H5)4N]4VO3 in the molar ratio 1 : 4. Nanocluster ...

A nanosensor, based on 8-hydroxyquinoline functionalized graphene oxide, was developed for the fluorescence detection of Zn

The monomer 2-{5-[4-((4-nitrophenyl)diazenyl)phenyl]-1,3,4-oxadiazol-2-ylthio}ethyl acrylate (NDPOE-acrylate) was synthesized in five steps and then copolymerized with N-isopropylacrylamide, leading to a dual pH and temperature responsive polymeric sensor. Obtained copolymer exhibited the lower critical solution temperature only in acidic medium (pH 2) as 32 °C. The UV–vis and fluorescence of copolymer was investigated at different pH values in various temperatures. The UV–vis of copolymer are independent to temperature above pH 4. The copolymer exhibited sensitive fluorescence change towards pH between 2 and 10 at different temperatures.

A nano-biosensor based on graphene oxide (GO) and 5-carboxy fluorescein (FAM) labeled DNA was developed for the detection of deletion mutation in exon 19 of EGFR gene, which led to the lung cancer. The method is based on the adsorbtion of FAM-labeled single-stranded DNA (fDNA) on GO, leading to fluorescence quenching of FAM. By addition of its complementary DNA (cDNA), a double-stranded DNA (dsDNA) was formed, resulted in recovering of fluorescence of FAM by desorbing and releasing from GO. While in the case of mismatched DNA, corresponding dsDNA was not formed, and therefore the fluorescence of FAM was not recovered.

The Heck coupling of haloarenes with various alkenes was successfully performed in the presence of 0.25 mol % PdCl2 and 0.5 mol % biphenyl-4-yl-[4(5)-(biphenyl-4-yl)-1H-imidazol-2-yl]ketone 2f as a ligand with Na2CO3 as optimal base, in a 1:1 mixture of H2O/DMF as the reaction solvent at 80 °C for 8 h. Imidazole 2f was found to be an inexpensive, air-stable, easily available, and efficient ligand in the palladium-catalyzed Heck reactions of aryl iodides (76 %--94 %), bromides (52 %--79 %), and chlorides (40 %--70 %).

An oxido-peroxido tungsten(VI) complex [WO(O2)L(CH3OH)] using salicylidene benzoyl hydrazine as a tridentate ONO donor Schiff base (H2L) has been synthesized and characterized by elemental analysis, IR, 1H NMR, molar conductance data, and single-crystal X-ray analysis. The complex was used as a catalyst for epoxidation of olefins and oxidation of sulfides. The results show that epoxides and sulfoxides were produced in high yield, turnover number, and selectivity.

Eftekhari-Sis, Bagher/0000-0001-8998-8040 WOS: 000318399000014 Willgerodt-Kindler reaction of arylglyoxal hydrates with secondary amines and elemental sulfur under solvent-free conditions at 80 degrees C is developed, in which alpha-ketothioamides are obtained in 70-90% yield in 0.6-1 hour. The X-ray crystal-structure analysis for one compound was obtained. Research Council of the University of Maragheh This work was supported by the Research Council of the University of Maragheh. B.E.S. gratefully acknowledges Mr. Biglari (IASBS) for recording NMR spectra.

A simple and efficient method for the synthesis of α-ketothioamides via the Willgerodt–Kindler reaction is developed. Reactions were carried out between arylglyoxal hydrates, amines and elemental sulfur in water at 80°C to afford corresponding α-ketothioamides in good to high yields in a short reaction time.

A method was developed for the detection of 185delAG mutation in BRCA1 gene, which is responsible for 85% and 63% lifetime risks of hereditary breast and ovarian cancer in women, respectively. The protocol is based on the quenching and recovering fluorescence emission of fluorescein-based dye (FAM)-labeled DNA in the presence of graphene oxide (GO), followed by addition of cDNA or mDNA. In addition, ligase reaction between a DNA probe attached to GO and a DNA possessing FAM on 5' terminal in the presence of cDNA or mDNA was applied.

New N-alkyl(aryl)-2,4-diaryl-1H-pyrrol-3-ol derivatives have been synthesized in moderate to good yields in a novel and efficient process by aldol reaction of 1-(4-methoxyphenyl)propan-2-ones with phenylglyoxal in the presence of DABCO in water, followed by Paal–Knorr reaction with amines in the presence of a catalytic amount of p-TSA in toluene at reflux.

At room temperature, and efficiently catalyze the direct Mannich-type reaction of varieties of in situ–generated aldimines using aldehydes and anilines with ketones in a three-component reaction under solvent-free conditions. The reaction proceeds rapidly and affords the corresponding β-amino ketones in good to high yields with good to excellent stereoselectivity. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency.

At room temperature, alcohols and phenols are efficiently protected with hexamethyldisilazane (HMDS) in the presence of silica sulfuric acid in good to excellent yields. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency.

Red mud (RM) is generated as a by-product during the production of alumina from bauxite ore. In this study, RM packing in a column is used as a catalyst for carbon–carbon double bond formation via Knoevenagel condensation. The reactants are added to the top of the column and then eluted with solvent. The products are collected in high yields and short time. RM packed in a column eliminates a catalyst separation step from the reaction mixture in this work.

For the first time, the Baylis-Hillman (BH) reaction of 2H-thiopyran-4(3H)-one is investigated, and surprisingly, the reaction of 2H-thiopyran-4(3H)-one with aldehydes in the presence of different tertiary amines shows excellent chemo- and regioselectivity in water. At room temperature, DBU affords BH adducts, but with DABCO, aldol products were obtained. In the case of DABCO, Et(3)N, or DMAP, domino aldol-rearrangement reactions occurred at 45-50 °C.

Manganeses(II) chloride supported on montmorillonite K10 was found to be an efficient catalysts for the oxidation of alcohols to carbonyl compounds with hydrogen peroxide as oxidant.