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Doxorubicin is an anticancer drug known for a variety of cancers. As a targeted drug, it is loaded onto branched graphene oxide nanoparticles (GONPs). In this research, polymeric coatings containin...

Quantitative structure–property relationship study was carried out for the prediction of photolysis half-lives of dihydroindolizines. Genetic algorithm variable selection was used in the multiple linear regression modeling. Four descriptors including topological (AAC), 2D-Autocorrelations (GATS7m), 3D-MoRSE (Mor19p), and GETAWAY (HATS3p) descriptors were selected by the algorithm, revealing that a hybrid of topologic, geometric, and electronic features of the molecule affects photolysis half-life of studied photochromic compounds. The results showed that the developed model provides statistically significant predictions of photolysis half-lives of dihydroindolizines. Copyright © 2016 John Wiley & Sons, Ltd.

A QSPR study was performed between descriptors representing the molecular structures and the ozonolysis half-lives of azo dyes. Five descriptors were selected on the training set by stepwise regression. Based on these five descriptors, a model with the squared correlation R2 = 0.90 was developed by using SW-MLR. All descriptors involved in the model were derived solely from the chemical structures of the dyes, which makes the model very useful to estimate the ozonolysis half-lives of the dyes before they are synthesized. Classification functions were also developed using the linear discriminant analysis (LDA) to classify studied azo dyes into foaming or non-foaming compounds. The reliability of the proposed models was further illustrated using various evaluation techniques.

In this paper the photolysis half-lives of the model dyes in water solutions and under ultraviolet (UV) radiation were determined by using a continuous-flow spectrophotometric method. A quantitative structureproperty relationship (QSPR) study was carried out using 21 descriptors based on different chemometric tools including stepwise multiple linear regression (MLR) and partial least squares (PLS) for the prediction of the photolysis half-life (t1/2) of dyes. For the selection of test set compounds, a K-means clustering technique was used to classify the entire data set, so that all clusters were properly represented in both training and test sets. The QSPR results obtained with these models show that in MLR-derived model, photolysis half-lives of dyes depended strongly on energy of the highest occupied molecular orbital (EHOMO), largest electron density of an atom in the molecule (ED+) and lipophilicity (logP). While in the model derived from PLS, besides aforementioned EHOMO and ED+ descriptors, the molecular surface area (Sm), molecular weight (MW), electronegativity (χ), energy of the second highest occupied molecular orbital (EHOMO-1) and dipole moment (µ) had dominant effects on logt1/2 values of dyes. These were applicable for all classes of studied dyes (including monoazo, disazo, oxazine, sulfonephthaleins and derivatives of fluorescein). The results were also assessed for their consistency with findings from other similar studies.

La0.5Ca0.5CoO3 perovskite-type oxide is prepared by sol–gel method. The physical and chemical properties of La0.5Ca0.5CoO3 were characterized by differential thermal analysis (DTA), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), Brunauer–Emmett–Teller (BET) method and IR techniques. The photocatalytic activity of the sample is evaluated by photocatalytic removal of Congo Red (CR) dye under UV light irradiation. The results of XRD and BET indicate that the perovskite-type oxide (LCCO) have a good crystal phase at 650 and 750°C with large specific surface area. The DTA, XRD, TEM, SEM, and EDX data revealed that LCCO nanoparticles are prepared successfully via sol–gel modified pechini method. The result showed that the degradation efficiency of CR by LCCO is excellent under UV light irradiation under our experiment condition.

In the present work, nanoporous alumina microspheres have been synthesized by sol–gel technique. Acid deficient aluminum nitrate and a mixture of equimolar HMTA-Urea were used as starting materials. The prepared sol then injected as droplets into hot oil column to give spherical shape. After calcinations the samples were characterized by scanning electron microscope, fourier transform infra-red spectroscopy, thermogravimetry–differential thermal analysis, X-ray diffraction and N2 adsorption–desorption isotherms. With respect to the results achieved from the above analyses, it was found that nanoporous alumina microspheres with controllable size and morphology can successfully be produced through sol–gel method.

BaPbO3 perovskite was prepared by the sol-gel method. The physical and chemical properties of catalyst were characterized by XRD, TEM, SEM, EDX and IR techniques. The photocatalytic activity of the sample was evaluated by photocatalytic decomposition of methylene blue (MB) dye under UV irradiation. The results of XRD indicate that the perovskite-type oxide (BaPbO3) is crystal at 700 °C. The XRD, TEM and SEM revealed that BaPbO3 particles are prepared in the nano-size regime. The results show that the degradation efficiency of methylene blue (MB) by BaPbO3 is higher than rutile under similar conditions.Keywords: Perovskite-type oxide, nanopowder, dye removal, methylene blue.

The organic-inorganic hybrids of glycine, tetraethylortho silicate (TEOS) and triethylphosphate (TEP) doped with silver ions were prepared by the sol-gel method. After moulding and heating at 600 °C to remove organic compound, porous Ag/P2O5-SiO2 monoliths were obtained. Scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectrum, transmission electron microscopy (TEM), infrared spectroscopy (FT-IR) and scanning tunnelling microscopy (STM) were used to structurally study monoliths. Surface area, pore volume and swelling degree of the samples were adjusted with different contents of TEP in the starting composition. Ag ions were stably released into the water at 30 °C for 28 days. Antibacterial experimentation revealed that such materials, treated at 600 °C, could restrain Escherichia coli effectively.KEYWORDS Antibacterial effect, nano-silver, phosphorous, organic–inorganic hybrid, sol-gel.