Selective Oxidation of Limonene over γ-Al2O3 Supported Metal Catalyst with H2O2

Liquid phase oxidation of limonene by hydrogen peroxide over the CeO2 and Fe2O3 catalysts supported by γ-Al2O3 was reported. Etly acetate and acetone were used as solvent to investigate the effect of the solvent on the oxidation reaction. The experiments were carried out at 80 °C The conversion of limonene and the selectivities of the carvone were calculated during the 10h reaction time. According to experimental results, maximum conversion of limonene and product selectivity of carvone were obtained with CeO2-γAl2O3 catalyst as 85% and 41%, respectively end of the 10 h reaction. The XRD analysis of the CeO2-γAl2O3 catalyst were performed

Collapse of the Small‐Angle Magnon Scattering in Fe as a Function of Magnetic Field

The dependence of the spin wave energy on the magnetization M⇒ and the applied magnetic field H⇒ in Fe (and other ferromagnets) has not been very well investigated with neutrons. According to the Holstein‐Primakoff dispersion relation, the contributions of the Zeeman energy gμBHgμBH and the dipole‐dipole interactions 4π gμBM sin2θq4πgμBMsin2θq do not simply add linearly to the exchange energy Dq2. However, in order to see these contributions, one must observe the very low energy (.01 – .1 mev) spin waves. One of the predictions of this dispersion relation is that the scattering of neutrons by spin waves near the origin should disappear as the magnetic field is increased. This is a consequence of the kinematics of the scattering process. Using our double‐Si crystal technique for small angle scattering we have experimentally observed this collapse at a field of about 8 kG in Fe at room temperature as predicted by theory. We have also measured the scattering due to these very low energy spin waves at temperatures up to .7 Tc and compared the data on an absolute scale with the theoretical cross section. The agreement is reasonably good.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87920/2/1340_1.pd

Sintering and properties of ZrO[2](Mg)-MgO composites

These studies shows which structures and properties have composites based on ZrO[2](Mg)-MgO sintered in a wide temperature range from 1400to 1650{о}С. X-ray diffraction showed an increasing of crystalline size with increasing of magnesia concentration. Decreasing of sintering temperature accompanied with an increasing of porosity and reduction of the compressive strength. Scanning electron microscopy showed the morphology of the composite structure. It is discovered that the pore size in the zirconia matrix in an order of magnitude higher than in magnesia inclusions

Crystal Structure Refinement of SrMoO4, SrWO4, CaMoO4, and BaWO4 by Neutron Diffraction

The crystal structures of CaMoO4, SrMoO4, SrWO4, and BaWO4 have been refined from neutron diffraction data taken in the (h0l)(h0l) and (hhl)(hhl) zones. Oxygen position refinement is started from the parameters proposed by Sillén and Nylander and results in an improvement of over an order of magnitude in the oxygen coordinates. A comparison of coordinates for the different compounds shows several systematic differences.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70371/2/JCPSA6-55-3-1093-1.pd

Elderly patients in emergency department: Dyspnea and chest pain

INTRODUCTION: As in all countries, the rate of geriatric group in the population is increasing rapidly in parallel with the improvement of life style.. Geriatric patients frequently refer to ED with cardiopulmonary complaints. The aim of study was to investigate the diagnosis distributions of geriatric patients with chest pain- respiratory distress. METHODS: This retrospective study was performed with 1343 patients over 65 years of age who were admitted to ED with respiratory distress- chest pain evaluated with computed tomography - cardiac enzyme levels. RESULTS: A total of 1343 patients with respiratory distress and chest pain from the geriatric age group were included in the study. 531 patients who were admitted due to trauma and more than one admission to hospital with the same complaints were excluded from the study. Respiratory distress and chest pain were observed in 343 of 812 patients (42.24%) cause of pulmonary, 247 (30.41%) patients cardiac, and 222 (27.33%) had due to other causes. In patients with pulmonary-related respiratory distress and chest pain, the most common cause was pneumonia (39.06%);and in 51.41% of patients with cardiac causes, acute myocardial infarction was detected. DISCUSSION AND CONCLUSION: We believe that to known the etiology of respiratory distress and chest pain will provide better patient evaluation. Considering that the number of geriatric patients who applied for emergency services increases day by day, the fact that emergency workers have more knowledge about geriatrics is an important factor that will increase the success rate of emergency department treatment

Slag Systems in Copper Recycling from Cu-Mg Scraps Slag Systems in Copper Recycling from Cu-Mg Scraps

Abstract Ever increasing metal consumptions starting with the industrial revolution, caused improper and irresponsible utilization of raw material sources. Initially, recycling concepts were purely based on economic motives. Today, however, it covers much broader concepts along with local economic views, such as globalization and environment. The rate of recycling from secondary raw materials is on the rise, and, therefore, not only the primary sources are conserved by the energy savings per unit ton of metal but also the secondary raw materials are rendered to be useful. For instance, the recycling ratio is more than 40% in terms of copper today. This study aims at determining a suitable slag system for the recycling of Cu-Mg scraps in order to obtain a slag with high fluidity. Oxygen and hydrogen absorption of these alloys, as well as the choice of refractories, represent major importance during the pyrometallurgical valorization of Cu and Cu alloys. The optimum experimental conditions for the valorization of Cu-Mg scraps (0.59% Mg) were found to be 1200 o C; a slag composition of 16% CaO, 49% FeO, 35% SiO 2 + B 2 O 3 ; chrome-corundum refractory brick with a ceramic-chemical bonding, and 30 minutes of reaction period. Characterization studies revealed that the slags produced did not contain free silicates [(Fe,Mg) 2 SiO 4 ], that their soluble impurity content was below the limits, and that they displayed a glassy appearance

Crystal structures of spinel-type Na2MoO4and Na2WO4 revisited using neutron powder diffraction

Time-of-flight neutron powder diffraction data have been collected from Na2MoO4 and Na2WO4 to a resolution of sin ([theta])/[lambda] = 1.25 Å-1, which is substanti­ally better than the previous analyses using Mo K[alpha] X-rays, providing roughly triple the number of measured reflections with respect to the previous studies [Okada et al. (1974). Acta Cryst. B30, 1872-1873; Bramnik & Ehrenberg (2004). Z. Anorg. Allg. Chem. 630, 1336-1341]. The unit-cell parameters are in excellent agreement with literature data [Swanson et al. (1962). NBS Monograph No. 25, sect. 1, pp. 46-47] and the structural parameters for the molybdate agree very well with those of Bramnik & Ehrenberg (2004). However, the tungstate structure refinement of Okada et al. (1974) stands apart as being conspicuously inaccurate, giving significantly longer W-O distances, 1.819 (8) Å, and shorter Na-O distances, 2.378 (8) Å, than are reported here or in other simple tungstates. As such, this work represents an order-of-magnitude improvement in precision for sodium molybdate and an equally substantial improvement in both accuracy and precision for sodium tungstate. Both compounds adopt the spinel structure type. The Na+ ions have site symmetry .-3m and are in octa­hedral coordination while the transition metal atoms have site symmetry -43m and are in tetra­hedral coordination