On-Surface Synthesis and Spectroscopic Characterization of Laterally Extended Chevron Graphene Nanoribbons

We report the on-surface synthesis and spectroscopic study of laterally extended chevron graphene nanoribbons (GNRs) and compare them with the established chevron GNRs, emphasizing the consistency of bandgap reduction of semiconducting GNRs with increased width. The laterally extended chevron GNRs grown on Au(111) exhibit a bandgap of about 2.2 eV, which is considerably smaller than the values reported for chevron GNRs in similar studies.     

The Supramolecular Self-Assembly of Aminoglycoside Antibiotics and their Applications

Aminoglycosides, a class of antibiotics that includes gentamicin, kanamycin, neomycin, streptomycin, tobramycin and apramycin, are derived from various streptomyces species. Despite the significant increase in the antibacterial resistant pathogens, aminoglycosides remain an important class of antimicrobial drugs due to their unique chemical structure which offers a broad spectrum of activity. The modification of antibiotics and their subsequent use in supramolecular chemistry is rarely reported. Given the importance of aminoglycosides, here we give a brief overview on the modification of 4,5- and 4,6-disubstituted deoxystreptamine classes of aminoglycosides through supramolecular chemistry and their potential for real world applications. We also make the case that the work in this area is gaining momentum, and there are significant opportunities to meet the challenges of modern antibiotics through the modification of aminoglycosides by harnessing the advantages of supramolecular chemistry.     

1H-1,2,4-Triazolo-5-diazonium salts in the synthesis of novel [1,2,4]triazolo[1,5-c][1,2,4]benzotriazin-6-ols

Chemistry of Heterocyclic Compounds - Condensation of 1H-1,2,4-triazolo-5-diazonium salts with 1,3-cyclohexanedione, accompanied by cascade processes of cyclization and oxidative aromatization,...     

Phyto-synthesis of silver nanoparticles using aerial extract of Salvia leriifolia Benth and evaluation of their antibacterial and photo-catalytic properties

Research on Chemical Intermediates - We have synthesized silver nanoparticles (Ag-NPs) via a simple and eco-friendly method through the utilization of aqueous aerial parts of Salvia leriifolia...     

Catalyst-free grinding method: a new avenue for synthesis of 6-amino-3-methyl-4-aryl-1H-pyrazolo[3,4-b]pyridine-5-carbonitrile and DFT studies on the mechanistic pathway of this category of compounds

Research on Chemical Intermediates - A novel, efficient, one-pot, catalyst-free grinding procedure for synthesis of 6-amino-3-methyl-4-aryl-1H-pyrazolo[3,4-b]pyridine-5-carbonitrile is reported....     

DFT study of SiO2 nanoparticles as a drug delivery system: structural and mechanistic aspects

Structural Chemistry - Adsorption and reaction mechanisms for the noncovalent and covalent functionalization of SiO2 nanoparticle (SiNP) with gemcitabine (GEM) anticancer drug have been...     

A cost-effective form-stable PCM composite with modified paraffin and expanded perlite for thermal energy storage in concrete

Journal of Thermal Analysis and Calorimetry - High thermal conductivity in phase change materials (PCM) is preferred in thermal energy storage (TES) systems. Carbon additives are considered as...     

Assessment of Environmental Quantitative Variation of Diosgenin in Fenugreek Seeds via High-Performance Thin-Layer Chromatography Method

JPC – Journal of Planar Chromatography – Modern TLC - Fenugreek is one of the oldest medicinal plants known by mankind. The aim of this study is to evaluate the effect of environmental...     

Thermodynamic properties of Ga27Si3 cluster using density functional molecular dynamics

Density functional molecular dynamical calculations have been carried out to explore the effect of silicon impurities on thermodynamic properties of Ga(30). We have obtained 500 distinct low energy equilibrium geometries of Ga(27)Si(3) in order to obtain reliable ground state geometry. The specific heat has been calculated using multiple histogram techniques and compared with that of Ga(30). We demonstrate that silicon impurities have a dramatic effect on the thermodynamic properties of the host cluster. In contrast to Ga(30), the specific heat of Ga(27)Si(3) shows a clear melting peak at ≈500 K, changing the character of Ga(30) from a nonmelter to a melter.     

负载于HZSM-5上的CuO-ZnO-Al2O3纳米粒子：尿素－硝酸盐燃烧合成和理化表征

用尿素-硝酸盐燃烧法制备了一系列的负载于HZSM-5上的CuO-ZnO-Al2O3纳米复合材料(CZA/HZSM-5)。研究了燃料与氧化物的比率对所合成的复合材料的理化性质的影响。用TGA/DTG,FTIR和XRD等研究了尿素-硝酸盐凝胶的热分解和煅烧粉体的相演变过程。FESEM结果表明在燃烧过程中燃料的用量对CZA/HZSM-5的性质有重大影响。CuO和ZnO的晶粒首先随尿素量的增加而增大,然后随尿素量的增加而减小。CuO和ZnO的相对结晶度随燃料量的增加表现为非单调趋势。随着燃料与硝酸盐的比率的增加,CZA/HZSM-5不仅形貌变得超细和均一,而且表面孔隙率也显著增加。FTIR结果表明HZSM-5的结构甚至在负载了CuO-ZnO-Al2O3纳米粒子后也未被破坏,而且在CuO和ZnO与HZSM-5之间还有表面的键合。TGA/DTG结果指出燃烧合成法是一种由若干过程组合起来的方法,例如前驱体的热分解和前驱体间的放热反应等。另外,提出了CuO-ZnO-Al2O3负载在HZSM-5上的生成机理。