Theoretical study of organic materials based on Thieno[2,3-b]thiophene as layer of bulk heterojunction solar cells

In this study, we report a theoretical investigations on the structural, optoelectronic and photovoltaic properties of a series of conjugated organic molecules containing thieno[2,3-b]thiophene, with different substituents. The DFT calculations were performed by using the quantum chemical methods using B3LYP [1] level with 6-31G(d) [2] basis set for all atoms. All calculations were realized by Gaussian 09 [3] program supported by GaussView 5.0.8 interface. Moreover, the optoelectronic properties (HOMO, LUMO, Egap…) were determined from the fully optimized structures. The absorption properties (λmax, Etr, OS) of these molecules are obtained by TD-B3LYP/6-31G(d) method [4].The studied oligomers can be subdivided in three categories; the first one constitutes by synthetized oligomers [5] but is characterized with the highest energy band values. Thanks to the effect of structural modifications in there chemical structures in the second and the third categories, the energy gap values have known a dramatic decrease. We conclude that these conjugated materials, especially of the third categories, are good candidates for bulk heterojunctions in organic solar cells applications.

An inorganic-organic hybrid material made of a silica-immobilized schiffbase receptor and its preliminary use in heavy metal removal

A novel and excellent host for heavy metals was synthesized by chemical immobilization of a (E)-4-((pyridin-2-yl-methylene)amino)phenol Schiff base receptor onto silica particles. The new hybrid material (SPSB) was analyzed and evaluated by elemental analysis, FT-IR spectroscopy, solid-state 13C NMR, scanning electron microscopy, BET surface area and BJH analyses. The surface exhibits good thermal stability determined by thermogravimetry and good chemical stability examined in various acidic and buffer solutions (pH 1–7). The coordination ability of SPSB was found to be most efficient in the pH range 6.5–8 for Hg2+, Cd2+, Pb2+ and Zn2+. Alkali coexisting ions did not interfere with separation and determination. The adsorbent can be regenerated at ease without destruction. Heavy metal removal performance (99 mg g−1) was found to be higher compared to previous literature reports

Ethnomedicinal and traditional uses of the Ferns of Khyber Pakhtunkhwa, Pakistan

Abstract Ferns are often used by indigenous people in Khyber Pakhtunkhwa, Pakistan. This study was designed to collect the ethnomedicinal and traditional knowledge of these locals about this group of vascular plants. Forty taxa belong to nineteen genera and ten families are used in the treatment of different diseases. The Pteridaceae was the most representative family with twelve taxa (30%), followed by Athyriaceae and Dryopteridaceae with six taxa each (30%), and Thelypteridaceae with five taxa (12.5%). Regarding the genera, Adiantum, Asplenium and Dryopteris ranked first with four taxa each (30%), followed by Aleuritopteris, Diplazium, Pteris and Equisetum with three taxa each (30%), followed by Athyrium, Oeosporangium, Polystichum and Pseudophegopteris with two taxa each (20%). These taxa were commonly used in the treatment of respiratory disorders i.e. asthma, bronchitis, emphysema, pneumonia; intestinal ulcer, stomach, urinary ailments and skin disorders by the methods of decoction and infusion. Traditional knowledge about ethnomedicinal plants is a valuable and essential source for the discovery of allopathic, herbal and homeopathic medicines.</jats:p

Evaluation of Pelargonium extract and oil as eco-friendly corrosion inhibitor for steel in acidic chloride solutions and pharmacological properties

International audienceThere is a growing trend in utilizing plant extracts and pharmaceutical compounds as corrosion inhibitors. Accurate identification of the essential oil of aerial parts of Pelargonium was obtained using hydrodistillation, gas chromatography and gas chromatography–mass spectrometry. The oil was predominated by citronellol (22.8 %). The inhibitory effect of essential oil and extract of Pelargonium was estimated on the corrosion of mild steel in 1 M hydrochloric acid (HCl) using weight loss, electrochemical impedance spectroscopy (EIS) and Tafel polarization curves. Inhibition was found to increase with increasing concentration of the essential oil and extractof Pelargonium. The effect of temperature on the corrosion behavior of mild steel in 1 M HCl with addition of essential oil and extract was also studied, and the thermodynamic parameters were determined and discussed. Values of inhibition efficiency were calculated from weight loss, Tafel polarization curves, and EIS. All results are in good agreement. Polarization curves showed that essential oil and extract of Pelargonium behave as mixed type inhibitors in HCl (1 M). The results obtained showed that the essential oil and extract of Pelargonium could serve as an effective inhibitor of the corrosion of mild steel in HCl solution. To avoid any unexpected toxicity, the majority of compounds have been studied by using POM analyses

Comparative sorption studies of chromate by nano-and-micro sized Fe2O3 particles

The comparative adsorption studies of Cr (VI) on nano and micro-powder Fe2O3 were investigated using kinetics and batch adsorption techniques. The uptake of chromate onto both the oxides of iron was observed to be dependent on the pH, contact time, temperature, media dosage and concentration of chromate anions. The values of sorption maxima were higher in the case of Fe2O3 nanopowder than the micro-powder which can be ascribed to the high surface area and point of zero charge (PZC) of the former oxide. The Dubinin-Radushkivech and Langmuir models were found well fitted for the description of the batch adsorption data. The FTIR studies confirmed that the hexavalent chromium was adsorbed onto both the iron oxides in the form of the Cr2O72−

Multidrug resistance reversal activity of extract and a rare dimeric naphthoquinone from Diospyros lotus

A dimeric naphthoquinone namely dihydrodyspyrole R (1) was purified once more from Diospyros lotus. Dihydrodyspyrole R and chloroform fractions were evaluated for their effects on the reversion of multidrug resistance (MDR). The compounds (1) and extract exhibited promising MDR reversing effect in a dose-dependent manner against mouse T-lymphoma cell line. Molecular docking of compound 1 revealed the correlation between in-silico with in-vitro results. The molecular docking results showed that compound 1 is bind closely where co-crystal ligand of P-gp is present. But usually, computational investigation predicts that, if a compound gives lesser score then compound will exhibit good activity. Hence, the docking scores of compound 1 are the near to the Rhodamine. It is conclude that there are certain important structural features of compound 1which are responsible for the inhibiting potency of P-gp from mice. The computational Petra/Osiris/Molinspiration (POM) analysis confirms the possibility of use of compound 1 without side effect or less toxicity risks

Exploring drivers of luxury brand buying behavior : An empirical study

The motivations that drive customers towards purchasing luxury brands have complex psychological underpinnings that warrant careful examination. This research paper examines the effect of brand image (BdI), brand trust (BdT) and brand affect (BdA) on luxury brand buying behavior with an aim to understand consumer motivations towards luxury brands. A structured questionnaire consisting of validated scales for the said constructs was administered to a sample of 390 consumers outside luxury brand stores within the Punjab province of Pakistan. For the data analysis, Partial Least Squares structural equation modeling (PLS-SEM) was used. We assessed the three correlations revealing significant relationships between the constructs. The empirical study makes an important contribution to the luxury brand management literature along with providing productive implications to academicians and experts

Arylhydrazono/Aryldiazenyl Pyrazoles: Green One-Pot Solvent-Free Synthesis and Anticancer Evaluation

The aim of this study was to synthesize and evaluate the biological activity of pyrazole derivatives, in particular, to perform a “greener” one-pot synthesis using a solvent-free method as an alternative strategy for synthesizing hydrazono/diazenyl-pyridine-pyrazole hybrid molecules with potential anticancer activity. Effective treatment for all types of cancers is still a long way in the future due to the severe adverse drug reactions and drug resistance associated with current drugs. Therefore, there is a pressing need to develop safer and more effective anticancer agents. In this context, some hybrid analogues containing the bioactive pharmacophores viz. pyrazole, pyridine, and diazo scaffolds were synthesized by one-pot method. Herein, we describe the expedient synthesis of pyrazoles by a onepot three-component condensation of ethyl acetoacetate/acetylacetone, isoniazid, and arenediazonium salts under solvent-free conditions, and the evaluation of their cytotoxicity using a sulforhodamine B assay on three cancer cell lines. Molecular docking studies employing tyrosine kinase were also carried out to evaluate the binding mode of the pyrazole derivatives under study. 1-(4-Pyridinylcarbonyl)-3- methyl-4-(2-arylhydrazono)-2-pyrazolin-5-ones and [4-(2-aryldiazenyl)-3,5-dimethyl-1H-pyrazol-1- yl]-4-pyridinylmethanones, previously described, were prepared using an improved procedure. Among these ten products, 1-isonicotinoyl-3-methyl-4-[2-(4-nitrophenyl)hydrazono]-2-pyrazolin-5-one (1f) displayed promising anticancer activity against the MCF-7, HepG2 and HCT-116 cell lines, with an IC50 value in the range of 0.2-3.4 μM. In summary, our findings suggest that pyrazoles containing hydrazono/ diazenyl and pyridine pharmacophores constitute promising scaffolds for the development of new anticancer agents. </jats:sec