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This work presents theoretical modeling of some systems, using density functional theory (DFT), for enhancing the photoresponse of a dye-sensitized solar cell. The optimization of the dye (NKX 2587) as well as the dye derivatives was carried out using B3LYP and 6-311g (d,p) level of theory, using DFT as incorporated in Gaussian 03 level of programming. The HOMO-LUMO energy gaps are lower for (CdSe)13 -Dye-(TiO2 )6 multijunction systems in comparison with both the isolated dyes as well as dye-TiO2 systems. The absorption peaks were found to be mostly red-shifted for (CdSe)13 -Dye-(TiO2 )6 multijunction systems with respect to the Dye-TiO2 systems, indicating the enhancement of the absorption behavior of the dye sensitizer by its interaction with the CdSe framework. The results thus indicate some sort of co-sensitization of the TiO2 by the dye sensitizer as well as the CdSe quantum dot and are hence expected to increase the efficiency of the solar device. © 2019 Wiley Periodicals, Inc.

Common mulberry weed (Fatoua villosa (Thunb.) Nakai) and creeping amaranth (Amaranthus crassipes Schlecht) are reported for the first time in Pakistan's flora as these were not listed in any other literature nor identified before in Pakistan. Plants were found as a result of taxonomic studies performed in 2013 in Peshawar, Pakistan. Detail study was performed for the exact identification. Morphological results were compared with Flora of China and Flora of North America. Plant distribution along with its habitat and adjacent species was also recorded. Scanning electron and light microscopy was performed for the confirmation of epidermal appendages on leaf epidermis and palyno-morphological characters.

Thermal properties of fossil fuel are the key fundamental characteristics, which can distinguish any compound as a potential fuel. The performance of diesel fuel blend along with stability and solubility parameter designs are evaluated. The results from the experimental study indicate that the increase in hydrogen peroxide (H2O2) amount enhances the cetane number of diesel fuel blend significantly. However, the calorific value decreases as compared to pure diesel fuel. All values performed well according to the ASTM D-975 diesel testing method. The thermodynamics of the prepared fuel blends also revealed that substantial solubility and diesel/H2O2 blend stability are provided even at lower temperatures. Such blends can be used as a feasible replacement of pure diesel fuel. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Calculations based on second-order Moller–Plesset and density functional theory (DFT) methods using different exchange and correlation functionals are performed on C2H4Nb organometallic complex for its hydrogen storage capacity. We found that this complex can store up to a maximum of 14 H2 molecules using Becke-3 Lee–Yang–Parr (B3LYP)/LanL2DZ method, with a gravimetric H2 uptake capacity of 18.92 wt% and average binding energy of 0.52 eV/H2. The evaluation of the temperature dependence of the Gibbs free energy change (ΔG) of H2 adsorption process indicates that the adsorption of H2 molecules is energetically favorable below 250 K using B3LYP (LanL2DZ) and PBEPBE (LanL2MB, LanL2DZ) level of theories. On the basis of the DFT descriptors, calculated at B3LYP (LanL2DZ) and B3PW91 (LanL2MB) level of theory, we found that the stability of the complex increases with increase in the number of H2 molecules adsorbed by the complex. © 2013 Wiley Periodicals, Inc.

Dendritic cells (DCs) are professional antigen-presenting cells (APCs) that play a critical role to activate immune response. They may be targeted for immunomodulation by microbes, including probiotics. In this study, chicken bone marrow dendrite cells (chi-BMDCs) were stimulated with lipopolysachride (LPS), Saccharomyces boulardii (Sb), Bacillus subtilis B10 (Bs), co-culture of Sb + Bs and phosphate buffer saline (PBS) as a control group (Ctr) at 3, 6, and 12 h intervals. Results revealed that treatment groups modulated the phenotype and biological functions of chi-BMDCs. Scan electron microscopy showed attachment of probiotics on the surface of chi-BMDCs. Additionally transmission electron microscopy (TEM) revealed efficiently engulfing and degradation of probiotics. Gene expression levels of MHC-II, CD40, CD80 and CD86 up-regulated in stimulated groups. Furthermore, toll-like receptors TLR1, TLR2, TLR4, and chicken specific TLR15 expressions were improved and downstream associated factors MyD88, TRAF6, TAB1, and NFκ-B mRNA levels increased in all treatment groups as compared to control. Surprisingly, NFκ-B response was noted significant higher in LPS treatment among all groups. Moreover, IL-1β, IL-17, IL-4, TGF-β, and IL-10 production levels were found higher, and lower concentration of INF-γ and IL-8 were observed in Sb, Bs, and Sb + Bs treatment groups. In contrast, LPS groups showed prominent increase in IL-12, INF-γ, and IL-8 concentration levels as compared to control group. Altogether, these results emphasize a potentially important role of Saccharomyces boulardii and Bacillus subtilis B10 in modulating immunological functions of chi-BMDCs by targeting specific toll like receptors (TLRs) and associated factors. The role of probiotics on chi-BMDCs functionality in a non-mammalian species have been presented for the first time. J. Cell. Biochem. 115: 189–198, 2014. © 2013 Wiley Periodicals, Inc.

C-Glycosidation plays a significant role in the synthesis of optically active scaffolds. Among C-glycosylations, C-alkynylation has emerged as a synthetic tool in organic or natural product synthesis since it make use of carbohydrates as chiral pool and source of carbon as well. In this present review several modes of C-alkynyl-glycosylations have been summarized based on different glycosyl donors such as glycals, anomeric acetates, anomeric halosugars, 1,2-anhydrosugars, 1,6-anhydrosugars, lactones, lactols and activated/unactivated terminal alkynes as a glycan partner under various Lewis acids like TiCl4, I2, BF3·OEt2, Cu(OTf)2, TMSOTf and/or metals like In, Zn. Further, total/fragment stereoselective synthesis of some important natural products has been elaborated.

Herein, we report our observations on voltammetric investigations about the redox behaviour of para-nitrotoluene, 1,4-benzoquinone and ferrocene, aimed at exploring the unusual aspects of ion-pairing phenomena in imidazolium-based room temperature ionic liquids (RTILs). Our observations indicate that the stabilization of electrogenerated ion/radical ion intermediates depends upon the potential of the working electrode and the overall composition of RTILs. In light of observed relative trends and quantum mechanical calculations, we propose that the ion-pair stabilization of electrogenerated charged species in RTILs is closely related to the structural organization and composition of electrode/RTIL interface. Copyright © 2012 John Wiley & Sons, Ltd.

Comparative quantitative-structure-toxicity-relationship models developed using various quantum chemical descriptors calculated at semiempirical (AM1, PM3), Hartree–Fock and density functional theory (DFT) (B3LYP) methods, are compared for predicting the toxicity (pIGC50) of 69 aliphatic compounds toward Vibrio fischeri. The multiple linear regression equations, which can assist in modeling toxicity of these compounds, are developed using molecular descriptor, log P (1-octanol/water partition coefficient) in conjunction with two quantum chemical descriptors, electrophilicity index (ω) and energy of the lowest unoccupied molecular orbital (ELUMO). The calculated toxicity values (PIGC50) based on the model equations are compared with the experimental data. In general, the stepwise model regression equations based on quantum chemical descriptor ω in combination with molecular descriptor log P, calculated at DFT(B3LYP) with 6-311G (d,p) and DGDVZP basis sets show better agreement with the experimental data. The electronic origin of the toxicity dependence on descriptors like log P, ω and ELUMO is traced to the cumulative contribution of the lipophilicity and electrophilicity of the chemical moieties to their toxic behavior. © 2012 Wiley Periodicals, Inc.

Summary Three types of shelf stable buffalo meat chunks (SBM) were prepared using three types of infusion solution formulations. These contained varying percentages of glycerol, sodium chloride, propylene glycol and honey, in addition to sodium nitrite @ 100 ppm and sorbic acid @ 0.2%. Meat chunks were pasteurised at 80 °C for 20 min and then desorbed under refrigeration, drained and dried at 80 °C. The SBM processed with ISF-3 (glycerol 6.0, propylene glycol 1.00 and sodium chloride 6.00%) had significantly lower salt and moisture content and significantly higher protein and haem pigments than the other two products. The SBM processed with ISF-1 (glycerol 9.5, propylene glycol 1.5, sodium chloride 7.5 and honey 2.0%) had significantly lower water activity but significantly higher yield and protein solubility than other two products. The SBM processed with ISF-2 (glycerol 2.5, propylene glycol 2.5, sodium chloride 8.5 and honey 1.0%) had significantly higher salt content and Thiobarbituric acid values than the other two products. All the three types of products had very good sensory acceptability and satisfactory microbiological qualities.

Cyclic molecular frameworks, especially the benzannulated medium-sized and macrocyclic ring (BMR) systems, constitute an integral component of a large number of biologically significant natural or synthetic molecules. Many of these BMR compounds are either approved as drugs or have reached the late developmental stages in clinical trials. Such cyclic systems have been shown to possess great potential, especially in the discovery of new anticancer leads. Efforts from synthetic chemists have led to the development of elegant new strategies for the construction of BMR scaffolds of medicinal importance. This review intends to highlight the importance of benzannulated medium-sized and macrocyclic rings (BMRs) and the strategies developed over the years for their synthesis.

The title compounds are prepared from stoichiometric mixtures of the metal nitrates dissolved in glycerin (120 °C, 12 h) followed by calcination in air (Pt crucible, 800 °C, 24 h).

Anomeric gem-diallylation, mono-β-crotylation and mono-β-propargylation of sugar 1,5 and 1,4 lactones have been achieved under Barbier reaction conditions using Zn powder and a catalytic amount of TMSCl as an activator. Ring closing olefin metathesis of the synthesized gem-diallyl derivatives furnished C-spiro cyclopentene glycosides. Finally, the cyclopentene rings were converted into carbohydrate based tricyclic morpholine fused triazole glycoconjugates as potential SGLT2 inhibitors.

It is proposed that the use of ultrasound irradiation is the major reason for the efficiency of the simple one-pot reaction of aromatic amines with triethyl orthoformate to afford formamidines and benzimidazole derivatives.

The synthesis of 8-, 9-, 10-, 11-, and 13-membered ring compounds having a carbohydrate ring fragment is established by intramolecular Sonogashira and Heck coupling reactions.

We report DFT studies on some perylene-based dyes for their electron transfer properties in solar cell applications. The study involves modeling of different donor-π-acceptor type sensitizers, with perylene as the donor, furan/pyrrole/thiophene as the π-bridge and cyanoacrylic group as the acceptor. The effect of different π-bridges and various substituents on the perylene donor was evaluated in terms of opto-electronic and photovoltaic parameters such as HOMO-LUMO energy gap, λmax, light harvesting efficiency(LHE), electron injection efficiency (Oinject), excited state dye potential (Edye*), reorganization energy(λ), and free energy of dye regeneration (ΔGdyeRegen). The effect of various substituents on the dye–I2 interaction and hence recombination process was also evaluated. We found that the furan-based dimethylamine derivative exhibits a better balance of the various optical and photovoltaic properties. Finally, we evaluated the overall opto-electronic and transport parameters of the TiO2-dye assembly after anchoring the dyes on the model TiO2 cluster assembly.

A variety of furanoses and pyranoses (14 examples) bearing a bromobenzyl and a terminal alkynyl group undergo the reaction in the presence of a heterogeneous basic alumina-supported palladium catalyst and CuI as co-catalyst to give benzannulated 10- to 13-membered macrocycles containing the carbohydrate moiety.

On the alkali metal tungsten bronzes, in particular those of potassium, rubidium and cesium