The thermal conductivity of CFC alternatives HFC-125 and HCFC-141b in the liquid phase

The liquid thermal conductivities of the CFC alternatives, HFC-125, and HCFC-141b measured by a transient hot-wire apparatus with one bare platinum wire are reported in the temperature ranges from 193 to 333 K (HFC-125, CHF₂, CF₃) and from 193 to 393 K (HCFC-141b,CCI₂F-CF₃), in the pressure ranges from 2 to 30 MPa (HFC-125) and from 0.1 to 30 MPa (HCFC-141b), respectively. The results have been estimated to have an accurancy of ±0.5%. The liquid thermal conductives obtained have been correlated by a polynomial of temperature and pressure which can represent the experimental results within the standard deviations of 0.49% for HFC-125 and 0.46% for HCFC-141b, respectively.     

A New Approach to Processing Rutile from Ilmenite Ore Utilizing the Instability of Pseudobrookite

Rutile (TiO₂) is a vital industrial material used in pigments and in many other valuable chemicals. A new production process to synthesize rutile from natural ilmenite ore and therefore overcome the environmental problems associated with conventional rutile extraction processes was developed. Because the simple phase separation of ilmenite (FeTiO₃) into Fe₂O₃ and TiO₂ occurs due to air oxidation, extracting TiO₂ by removing Fe₂O₃ may be possible if pseudobrookite (Fe₂TiO₅), known as a stable compound in the Fe₂O₃-TiO₂ system at higher temperatures, is of unstable phase in the lower-temperature range. In order to clarify the potential of this new approach, the phase stability of pseudobrookite in the lower-temperature range is discussed. The free energy of formation of pseudobrookite from the respective pure oxides was measured at temperatures ranging from 1073 K to 1473 K by the chemical equilibrium technique using Al₂O₃ as the reference oxide. The observed free energy is given as a function of temperature: ?G⁰ = 7715 ? 7.7T (J/mol). The results indicate that pseudobrookite has an unstable phase below 929 K. This has important industrial implications as a new approach to producing synthetic rutile from ilmenite ore by oxidation at low temperatures and acid leaching.     

EPA and DHA Status of South Asian and White Canadians Living in the National Capital Region of Canada

To minimize the risk of cardiovascular disease (CVD), most dietary guidelines have recommended consuming 500 mg/day of eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) or two servings of oily fish/week. The sum of percent EPA and DHA in red blood cell (RBC) total fatty acids-termed the omega-3 index-has been proposed as a biomarker for assessing the risk of death from CVD. The omega-3 indices of ≤4, >4 to <8 and ≥8 % have been proposed to be associated with high, intermediate and low CVD risks, respectively. In this study, we determined the EPA + DHA intake level and the omega-3 index of South Asian Canadians (SAC; n = 308) and white Canadians (WC; n = 341) age 20–79 years living in the National Capital Region of Canada. The mean EPA + DHA intake levels were 569 ± 571 mg/day for SAC and 684 ± 865 mg/day for WC and 46 % of SAC and 43 % of WC met the recommended EPA + DHA intake level of 500 mg/day. The mean omega-3 indices were 6.6 and 5.9 % for SAC and WC respectively. The suggested cardio-protective target level for the omega-3 index of ≥8 % was observed only in 19.8 % of SAC and in 9.4 % of WC subjects. The majority of the participants (74.4 % of SAC and 82.7 % of WC) were in the >4 to <8 % range. These results suggest that although study participants’ dietary intake of EPA + DHA is adequate, this intake was not sufficient to provide an omega-3 index that is considered cardio-protective.     

Experimental determination of the thermal diffusivity of molten alkali halides by the forced Rayleigh scattering method. II. Molten NaBr,KBr, RbBr,and CsBr

This is a companion to an earlier paper (on molten alkali metal chlorides) which gives experimental results for the thermal diffusivity of four molten alkali metal bromides: NaBr, KBr, RbBr, and CsBr. The measurements were performed with a forced Rayleigh scattering instrument at temperatures up to 1326 K. The overall uncertainty in the measured thermal diffusivity is estimated to be ±3 to ±11%, depending on the measured salts. The results converted to thermal conductivity show one of the smallest values among other earlier experimental data obtained mainly by the steady-state methods. It is also found that the temperature dependence of the thermal conductivity is weakly negative.     

A twin optically-pumped far-infrared CH3OH laser for plasma diagnostics

A twin optically-pumped far-infrared CH₃OH laser has been constructed for use in plasma diagnostics. The antisymmetric doublet due to the Raman-type resonant two-photon transition is reproducibly observed at 118.8 μm. With the 118.8-μm line, it is obtained from the frequency separation of the anti-symmetric doublet that CH₃OH absorption line center is 16±1 MHz higher than the pump 9.7-μm P(36) CO₂ laser line center. It is shown that the Raman-type resonant two-photon transition is useful in order to get several-MHz phase modulation for the far-infrared laser interferometer. Some preliminary performances of this twin laser for the modulated interferometer are described.     

Magneto-optical measurements with a hybrid magnet

An FFT spectrometer has been constructed to measure magneto-optical spectra in the far-infrared region (3 to 40 cm^?1) with a hybrid magnet system. The magneto-absorption was studied in the spin-Peierls cuprate CuGeO₃ at various magnetic fields. Coil constants of superconducting magnet and resistive one, of which a hybrid magnet consists, were calibrated by ESR spectra at the constant field.     

Pharmacological effects of BAM-1120, a novel ergoline derivative, on central dopaminergic functions in rats

Based on data gathered from patients, psychiatrists, and social workers at the Hawaii State Hospital, it was determined that the majority of patients had been in the hospital for more than one year, were committed for forensic reasons, and did not need continued hospitalization. An inter-agency systems approach is needed to address the issue of length of patient stay.     

Preparation and Nonlinear Optical Properties of Quantum-Sized CuCl-Doped Silica Glass by the Sol–Gel Process

The sol–gel process has been applied successfully to the preparation of small-sized CuCl-doped silica glass with a significant quantum-sized effect. Gel synthesized by the hydrolysis of a complex solution of Si(OC₂H₅)₄ and CuCl with an HCl catalyst is heated to 900°C to form fine, cubic CuCl crystals. Above 700°C, absorption peaks observed at ∼370 and ∼380 nm are attributed to the excitation of confined Z_1,2 and Z₃ excitons, respectively, in the CuCl microcrystals. As the size of the CuCl crystals decreases, exciton energy shifts to the higher-energy side. The resonant third-order nonlinear susceptibility at 77 K is 1.1 × 10⁻⁸ esu, which originates from the enhancement by the quantum-sized effect of the exciton.     

“In Situ” Observation of Smelting Reduction and Carburization of Iron Ore with Carbonaceous Materials by Laser Scanning Microscope

It is a very valuable key technology to accelerate the rates of smelting reduction of iron ore and the succeeding carburization at low temperatures for lower energy consumption in the iron‐making process. It is well known that the smelting reduction and carburization are very complicated phenomena, but the mechanism has not yet been brought into daylight. It is considered that the molten iron oxide containing slag among carbonaceous materials and reduced iron is strongly concerned in the phenomena. Thereupon, an experimental model is made in the present work, and “in situ” observation was made on the smelting reduction and carburization phenomena at iron‐making temperatures by a laserscanning microscope. The mechanism of the phenomena is discussed based on the observed results and concentration profiles of carbon in quenched iron samples.