A simple and efficient procedure for the synthesis of N-substituted acryl amides has been developed using Na2CO3/SiO2 or NaHSO4/SiO2. smoothly acts as a base in reaction between acryloyl chloride variety amines to obtain their corresponding products good excellent yield. Additionally, NaHSO4/SiO2 catalyzed Ritter nitrile sec-benzylic alcohols give expected amide product. In both reactions, were...

Point-counted modes, representative mineral analyses, and whole-rock majorand trace-element compositions determined by X-ray fluorescence spectroscopy and inductively coupled plasma mass spectroscopy (ICP-MS) are presented for 11 samples of the hornblende^andesite block-lava flows erupted from Volca¤n de Colima in 1991 and 1998^1999. New ICP-MS trace-element data are also presented for 37 andes...

Quartz solubility in H2O-CO2 fluids was measured at 800 °C and 10 kbar. Mixed fluids were generated from hydrous oxalic acid, silver oxalate, silver carbonate, and liquid H2O; solubility was determined by weight changes of the quartz crystals. Stringent blank tests and weighing procedures were used to establish the CO2 and H2O contents of experimental fluids. Using experimentally constrained mo...

Dopamine (DA), noradrenaline (NE) and epinephrine (EA) are important biological neurotransmitters belonging to the class of catecholamines that are present in mammals. Catecholamines have only a brief duration of action and are ineffective when administered orally, because they are rapidly inactivated in the intestinal mucosa and the liver before reaching the systemic circulation. These neurotr...

We review our recent work on the physical mechanisms limiting the mobility of graphene on SiO2. We have used intentional addition of charged scattering impurities and systematic variation of the dielectric environment to differentiate the effects of charged impurities and short-range scatterers. The results show that charged impurities indeed lead to a conductivity linear in density (σ(n) ∝ n) ...

The distorted octahedral complexes [SnCl4{ BuSe(CH2)nSe Bu}] (n = 2 or 3), (1) and (2), obtained from reaction of SnCl4 with the neutral bidentate ligands and characterized by IR/Raman and multinuclear (H, Se{H} and Sn) NMR spectroscopy and X-ray crystallography, serve as very effective single source precursors for low pressure chemical vapor deposition (LPCVD) of microcrystalline, single phase...

The (n,m) population distribution of single-walled carbon nanotubes obtained on supported CoMo catalysts has been determined by photoluminescence and optical absorption. It has been found that the (n,m) distribution can be controlled by varying the gaseous feed composition, the reaction temperature, and the type of catalyst support used. When using CO as a feed over CoMo/SiO2 catalysts, increas...

Vertical structured Gallium nitride (GaN) p-n junction diodes with improved breakdown properties have been demonstrated using high-k dielectric passivation underneath the field plate. Simulation results at a reverse voltage of 1 kV showed that the maximum electric field near the mesa-etched p-n junction edges covered with film of dielectric constant k = 10 was reduced to 2.0 MV/cm from 3.0 MV/c...

OBJECTIVES This study evaluated the influence of air-particle abrasion protocols on the surface roughness (SR) of zirconia and the shear bond strength (SBS) of dual-polymerized resin cement to this ceramic. MATERIALS AND METHODS Sintered zirconia blocks (n = 115) (Lava, 3M ESPE) were embedded in acrylic resin and polished. The specimens were divided according to the 'particle type' (Al: 110 µ...