Combining MoS<Subscript>2</Subscript> or MoSe<Subscript>2</Subscript> nanoflakes with carbon by reacting Mo(CO)<Subscript>6</Subscript> with S or Se under their autogenic pressure at elevated temperature

This paper describes a non-aqueous, solvent-free, environmentally friendly, one-pot facile reaction to synthesize inorganic materials inclusion with carbon (MoS₂ or MoSe₂/C) at low temperatures. Nanoflakes of MoS₂ and MoSe₂ inclusion with carbon are prepared by a thermal (750 °C) reaction between Mo(CO)₆ and S or Se at their autogenic pressure in a closed reactor under inert atmosphere. Elemental sulfur or selenium powders are chosen in order to avoid the use of highly toxic H₂S and H₂Se gases. Without further processing of the as-prepared MoS₂/C or MoSe₂/C products, their compositional, morphological and structural characterization are carried out. The possibility of hydrogen storage in as-synthesized MoS₂/C or MoSe₂/C products is examined. A probable reaction mechanism for the formation of MoS₂ or MoSe₂ nanoflakes inclusion with C is discussed.     

微波加热制备尺寸各向异性纳米金属钌颗粒

采用微波加热Polyol法以PVP作为稳定剂,首先快速合成了晶粒尺寸为2～6nm具有不同长宽比的各向异性的单分散金属钌胶体颗粒.以单分散胶体颗粒为晶种,获得不同团聚程度的纳米金属钌颗粒.高分辨电子显微镜(HRTEM)研究表明,树枝状纳米金属钌是由随机取向的金属钌单晶颗粒组成的.     

A Zn‐Doped CuO Nanocomposite Shows Enhanced Antibiofilm and Antibacterial Activities Against Streptococcus Mutans Compared to Nanosized CuO

Zinc‐doped copper oxide and copper oxide nanoparticles (NPs) are synthesized and deposited on artificial teeth by sonic irradiation, and the ability of these coatings to restrict biofilm formation by Streptococcus mutans is examined. The CuO and Zn:CuO NP‐coated teeth show significant reductions in biofilm formation of 70% and 88%, respectively, compared to uncoated teeth. The mechanism of the Zn:CuO nanoparticles is investigated, revealing that the nanoparticles attach to and penetrate the bacteria and generate intracellular reactive oxygen species (ROS) that enhance lipid peroxidation and cause cell death. Conversely, the CuO or ZnO NPs do not show this behavior and could not generate intracellular ROS. These results highlight the superior efficacy of Zn:CuO nanocomposites over CuO and ZnO NPs and the role of ROS in their antimicrobial effect.     

Creation of Shock-Abrasion Resistance Build-up Metal Using a Physicochemical Model of High-Temperature Processes

Build-up metal for shock-abrasion resistance was the focus of this work, where the mathematical model of physicochemical high-temperature processes developed by the authors in their previous works was used. A computer program based on the model permitted forecasting of the required chemical composition and structure of the build-up metal. Flux-cored wires were fabricated from a cold-rolled ribbon (1008 steel) and filled with a powder mixture. Low carbon steel (A 516) was used as the base metal. The specimens were prepared by 3-layered build-up. The prepared specimens were tested using light microscopy, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDS), hardness measurements, and shock-abrasion resistance measurements. The results of the above-mentioned tests confirmed the correct calculation of the model and the good shock-abrasion resistance of the suggested build-up metal.     

Effect of surfactant concentration on the size of coated ferromagnetic nanoparticles

We demonstrate that the average size of the coated ferromagnetic Fe₂O₃ nanoparticles is controlled by the surfactant concentration in the coating solution. Magnetization as a function of this ratio first increases and then decreases exhibiting a peak. Surface area of the coated material shows inverse behavior, i.e. first decreases and then increases. Both curves have extrema at the same ratio of surfactant/substrate. We explain these features in terms of competition between surface and volume contribution to the total energy, where surface contribution is determined by the bonding energy between the surfactant SH-group and Fe₂O₃. We support our conclusions by employing transmission electron microscopy and elemental analysis.     

Successful treatment of early secondary myelofibrosis in SLE with IVIG

With increasing demand for esthetics, dentists face the challenge of delivering definitive restorations that fulfill patients' expectations of esthetics, biocompatibility, and durability. Recent technical developments have encouraged fabrication of gold-reinforced porcelain inlays that meet these important criteria. This article describes a sequence to construct metal-reinforced porcelain inlay restorations.     

Semi-automatic computer construction of three-dimensional shapes for the finite element method

Seven patients with idiopathic Parkinson's disease, aged 62 to 76 years, average duration of the disease approximately eleven years, suffering from severe hallucinosis and paranoid delusions of different degree, in whom conventional therapeutic strategies (administration of benzodiazepines and mild neuroleptics) had no antipsychotic effect, received clozapine, a non-classical highly potent neuroleptic, while blood count was strictly monitored. Paranoid ideas disappeared in all seven patients after a maximum of four days administration of 25-125 mg/day. No deterioration of parkinsonian symptoms, quantified according to UPDRS was seen. Given the protection of clozapine, we could increase the L-dopa dose in two cases, thereby improving the patients' motor function. Blood count showed no abnormalities in any of the patients during an average observation period of seventeen months. Our results support the assumption that clozapine has a potent antipsychotic effect in the treatment of psychotic decompensation in advanced Parkinson's disease in carefully selected patients. We saw no negative influence of the neuroleptic on extrapyramidal symptoms.     

Biological treatment of chemical industry effluents by stabilization ponds

The aim of the work has been to develop a biological treatment for chemical industry effluents.

A multistage photosynthetic chemostat, fed by chemical industry effluents, was operated continuously as a bench scale experiment aimed at testing the possibility of treating these effluents by means of stabilization ponds. 70–80% of COD and 80–85% of BOD could be removed together with the pesticidal activity present in the raw wastewater. Optimal number of reactors was found to be 6.

Most of the COD and BOD elimination took place during a 30 day detention time. The effluents cannot be considered suitable for free discharge, but can be disposed of by irrigating carefully a halotolerant vegetation.     

Improved efficiency of dye sensitized solar cells by treatment of the dyed titania electrode with alkyl(trialkoxy)silanes

Dye sensitized cells are improved by passivation of the dyed titania electrode by silanizing the dyed surface with alkyl(trialkoxy)silanes. In cells utilizing the ruthenium dye bis(4,4′-dicarboxy-2,2′-bipyridine)bis(thiocyanato)ruthenium (II) (N3) optimum performance is produced by treating the dyed electrode with octyl(trimethoxy)silane in dry toluene. Such treatment increases efficiency as much as 66%, raising cells utilizing an ionic liquid electrolyte with high [I₃⁻] from 1.7% to 2.8% (1 sun AM1.5). The effect on dark currents and on cell efficiencies of this silanization and of dyeing both the FTO and TiO₂ surfaces is discussed for ionic liquid and acetonitrile based electrolytes.