Carbon Dioxide Reforming of Methane over Ni Catalysts Supported on Al2O3 Modified with La2O3, MgO, and CaO

The preparation of synthesis gas from carbon dioxide reforming of methane (CDR) has attracted increasing attention. The present review mainly focuses on CDR to produce synthesis gas over Ni/MO_x/Al₂O₃ (X = La, Mg, Ca) catalysts. From the examination of various supported nickel catalysts, the promotional effects of La₂O₃, MgO, and CaO have been found. The addition of promoters to Al₂O₃-supported nickel catalysts enhances the catalytic activity as well as stability. The catalytic performance is strongly dependent on the loading amount of promoters. For example, the highest CH₄ and CO₂ conversion were obtained when the ratios of metal M to Al were in the range of 0.04–0.06. In the case of Ni/La₂O₃/Al₂O₃ catalyst, the highest CH₄ conversion (96%) and CO₂ conversion (97%) was achieved with the catalyst (La/Al = 0.05 (atom/atom)). For Ni/CaO/Al₂O₃ catalyst, the catalyst with Ca/Al = 0.04 (atom/atom) exhibited the highest CH₄ conversion (91%) and CO₂ conversion (92%) among the catalysts with various CaO content. Also, Ni/MgO/Al₂O₃ catalyst with Mg/Al = 0.06 (atom/atom) showed the highest CH₄ conversion (89%) and CO₂ conversion (90%) among the catalysts with various Mg/Al ratios. Thus it is most likely that the optimal ratios of M to Al for the highest activities of the catalysts are related to the highly dispersed metal species. In addition, the improved catalytic performance of Al₂O₃-supported nickel catalysts promoted with metal oxides is due to the strong interaction between Ni and metal oxide, the stabilization of metal oxide on Al₂O₃ and the basic property of metal oxide to prevent carbon formation.     

Employing electrostatic self-assembly of tailored nickel sulfide nanoparticles for quasi-solid-state dye-sensitized solar cells with Pt-free counter electrodes

A low cost, low-temperature processable, highly efficient nickel sulfide counter electrode is demonstrated. Using the tailored, preformed nickel sulfide nanoparticles and electrostatic self-assembly, a novel counter electrode was fabricated that exceeded the efficiency of a conventional Pt-based cell.     

The biological response of spermidine induced by ionization radiation

Globally, there are concerns over the risks associated with radiation exposure, so it is important to understand the biological effects of radiation exposure. Driven by the need to detect the presence of radiation exposure, biomarkers to monitor potential exposure after radiological accidents can be developed and would be extremely valuable for biological response. In this study, the behavior of spermidine as a biomarker was investigated in a C57BL/6 mouse model exposed to an acute whole-body sublethal dose of 6 Gy. The spermidine content values in serum increased for up to two days after 6 Gy irradiation. However, the enhanced spermidine content observed on day +3 in irradiated mice returned to normal levels on the subsequent five days. The result indicates that spermidine can be used as a biomarker of biological response to radiation exposure.     

Electrochemical performances of Li–Mn spinel synthesized from nanosized chemical manganese dioxide

Li–Mn spinel (LiMn₂O₄) is prepared from several chemical manganese dioxides (CMDs) and the electrochemical performances are compared. The CMDs are synthesized via a redox process involving the simultaneous reduction and oxidation reaction of manganese ions in starting materials to converge to MnO₂. KMnO₄ is used as an oxidizing agent and various manganese(II) salts as reducing agents in the redox process. The crystalline phase, particle size and shape, and specific surface area (SSA) of the CMDs and the Li–Mn spinels are examined. The influence of the starting manganese salts on the above properties is also investigated. The CMDs form as aggregates of nanosized particles with different crystalline phase according to the starting manganese salts. Pure Li–Mn spinel phase is obtained from the CMDs irrespective of the different crystalline phases. The charge and discharge profiles of the LiMn₂O₄ are measured and compared.     

Di‐μ‐methoxo‐bis({N,N′‐bis­[2‐(3,5‐di­methyl­pyrazol‐1‐yl)­ethyl]­amine‐κ3N}copper(II)) bis­(hexa­fluoro­phosphate)

The title compound, [Cu₂(C₁₄H₂₃N₅)₂(CH₃O)₂](PF₆)₂, has a doubly methoxo‐bridged centrosymmetric copper dimer cation involving two tridentate bis­(pyrazolyl)­amine ligands. The geometry of each Cu^II atom is a distorted square pyramid with two N atoms of the pyrazole in bis­[2‐(3,5‐di­methyl‐1‐pyrazolyl)­ethyl]­amine (bpea) and two μ₂‐bridging O atoms of the methoxo ligands forming the basal plane, and the amine N atom occupying the axial position. In the bridging plane, the Cu—O bond lengths are 1.940 (4) and 1.942 (4) Å, and the bond angles for O—Cu—O and Cu—O—Cu are 76.1 (2) and 103.9 (2)°, respectively. The Cu?Cu distance is 3.058 (1) Å. The central four‐membered ring lies on an inversion centre.     

Isolation and Crystal Structure of [Cu(L1)(O2CH)](ClO4)?·?H2O: Hydrolysis of DMF ( N , N -Dimethylformamide) by a Copper(II) Tetraazamacrocycle

The tetraazamacrocyclic copper(II) complex, [Cu(L)](ClO₄)₂ (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14.4.0^1.18.0^7.12]docosane), hydrolyzes DMF at room temperature. The formate anion which is one of the hydrolyzed species of DMF coordinates to the copper(II) ion to form [Cu(L1)(O₂CH)](ClO₄) · H₂O (1). The crystals of the complex 1 were isolated and structurally characterized by a combination of analytical, spectroscopic, and crystallographic methods. In 1, the macrocyclic ligand contains two trans fused cyclohexane rings, and the coordination geometry about the copper(II) ion adopts a square pyramid with four equatorial nitrogen atoms from the macrocycle and an oxygen atom from the formato ligand with an uncoordinated perchlorate ion.     

Screening of anti-obesity agent from herbal mixtures

Globally, one in three of the World's adults are overweight and one in 10 is obese. By 2015, World Health Organization (WHO) estimates the number of chubby adults will balloon to 2.3 billion--Equal to the combined populations of China, Europe and the United States. The discovery of bioactive compounds from herbs is one possible way to control obesity and to prevent or reduce the risks of developing various obesity-related diseases. In this study, we screened anti-obesity agents such as methyl gallate from the herbal composition known as HemoHIM that actively inhibits lipid formation as evidenced by Oil Red O staining and triglyceride (TG) contents in 3T3-L1 adipocytes, suggesting their use as an anti-obesity agent. Furthermore, the amount of glycerol released from cells into the medium had increased by treatment of methyl gallate in a concentration-dependent manner. The present study suggests that a promising anti-obesity agent like methyl gallate might be of therapeutic interest for the treatment of obesity.     

Palladium-Catalyzed Coupling Reaction of Iodouracil Having Acetamidine Moiety with Olefins

The reaction of 6-[1-Aza-2-(dimethylamino)prop-l-enyl]-5-iodo-1,3-dimethyluracil (3) with various olefins in the presence of a catalytic amount of Pd(OAc)₂ and 1.5 equiv. of K₂CO₃ in DMF at 120 °C gave the pyrido[2,3-d]pyrimidine derivatives (5a-b and 7a-d) in moderate to high yield.