Spectral Properties of Graphene with Periodic Array of Defects in a Magnetic Field

Graphene with a periodic array of defects in a homogeneous magnetic field is considered. We suggest a solvable model of the system. Three types of defects are studied. The spectra of the Hamiltonians have the Hofstadter butterfly type. The comparison of the spectrum for pure graphene and one for the system having defects of each type is made.     

Surrounded Vaidya black holes: apparent horizon properties

We study the thermodynamical features and dynamical evolutions of various apparent horizons associated with the Vaidya evaporating black hole surrounded by the cosmological fields of dust, radiation, quintessence, cosmological constant-like and phantom. In this regard, we address in detail how do these surrounding fields contribute to the characteristic features of a surrounded dynamical black hole in comparison to a dynamical black hole in an empty background.     

XANES/EPR Evidence of the Oxidation of Nickel(II) Quinolinylpropioamide and Its Application in Csp3−H Functionalization

An in situ generated oxidation species of nickel quinolinylpropioamide intermediate was produced. Characterization by X-ray absorption near edge structure (XANES) and EPR provides complementary insights into this oxidized nickel species. With aliphatic amides and isocyanides as substrates, a nickel-catalyzed facile synthesis of structurally diverse five-membered lactams could be achieved.     

Solid-State NMR Spectroscopy: A Powerful Technique to Directly Study Small Gas Molecules Adsorbed in Metal–Organic Frameworks

Metal–organic frameworks (MOFs) have shown great potential in gas separation and storage, and the design of MOFs for these purposes is an on-going field of research. Solid-state nuclear magnetic resonance (SSNMR) spectroscopy is a valuable technique for characterizing these functional materials. It can provide a wide range of structural and motional insights that are complementary to and/or difficult to access with alternative methods. In this Concept article, the recent advances made in SSNMR investigations of small gas molecules (i.e., carbon dioxide, carbon monoxide, hydrogen gas and light hydrocarbons) adsorbed in MOFs are discussed. These studies demonstrate the breadth of information that can be obtained by SSNMR spectroscopy, such as the number and location of guest adsorption sites, host–guest binding strengths and guest mobility. The knowledge acquired from these experiments yields a powerful tool for progress in MOF development.     

Synthesis of 9-Arylhexahydroacridine-1,8-diones Using Phosphate Fertilizers as Heterogeneous Catalysts

Russian Journal of Organic Chemistry - A new strategy has been proposed for the synthesis of 9-arylhexahydroacridine-1,8-diones by three-component condensation of aromatic aldehydes with...     

Heat Transfer in Porous Microchannels with Second-Order Slipping Boundary Conditions

Transport in Porous Media - The paper presents results of a study of forced convection in a vertical flat and circular microchannels incorporating porous medium under slip boundary conditions of...     

Impact Force Identification on Carbon Fibre–Epoxy Honeycomb Composite Panel Based on Local Convex Curve Criterion

Experimental Mechanics - Identification of impact force is essential for various engineering applications, such as performance evaluation, design optimisation, noise suppression, and vibration...     

In-Vivo Soft Tissues Mechanical Characterization: Volume-Based Aspiration Method Validated on Silicones

Experimental Mechanics - Simulating the deformations of soft tissues has gained importance in recent years due to the development of 3D patient-specific biomechanical models in the context of...