Preparation of fine particles of carnegieite by a mist decomposition method

A mist of a hydrosol consisting of silica, alumina/NaAlO₂ and sodium hydroxide was produced by a supersonic atomization, and treated successively in three furnaces of different temperatures. The temperatures of the furnaces were adjusted for the evaporation of water, the dehydration and the crystallization of the mixed oxide, respectively. The spherical particles ( 0.5m) of carnegieite were found to be formed in a narrow composition range of the raw materials at temperatures of 650 to 900° C. The factors affecting the properties of the particles were investigated.     

Protective effect of phytic acid hydrolysis products on iron-induced lipid peroxidation of liposomal membranes

Beneficial effects of dietary phytic acid (myo-inositol hexaphosphate; IP₆) have often been explained by its strong iron ion-chelating ability, which possibly suppresses iron ion-induced oxidative damage in the gastrointestinal tract. Because phytic acid is hydrolyzed during digestion, this work aimed to know whether its hydrolysis products (IP_2′ IP_3′, IP_4′ and IP₅) could still prevent iron ion-induced lipid peroxidation. Studies using liposomal membranes demonstrated that hydrolysis products containing three or more phosphate groups are able to inhibit iron ion-induced lipid peroxidation although their effectiveness decreased with dephosphorylation. Similarly, they also prevented iron ion-induced decomposition of phosphatidylcholine hydroperoxide. These results demonstrate that intermediate products of phytic acid hydrolysis still possess iron ion-chelating ability, and thus they can probably prevent iron ion-induced lipid peroxidation in biological systems.     

Hydrophilic surface modification of polypropylene films by CCl4 plasma

The CCl₄ plasma treatment of polypropylene films was investigated from the viewpoint of hydrophilic surface modification using a contact-angle meter, ATR FTIR spectroscopy, and angular XPS. Hydrophilicity and chemical composition of the CCl₄ plasma treatment was effective in hydrophilic modification. The advancing contact angle of water for polypropylene films was decreased from 99° to 81-7° by the CCl₄ plasma treatment, and the surface energy increased from 27.2 to 38.9-67.7 mJ/m² when the discharge current varied from 50 to 150 mA. The CCl₄ plasma initiated chlorination, oxidation, and aluminum sputtering reactions. The chlorination of polypropylene films was favorable in a mild CCl₄ plasma operated at discharge current of 50 mA. The oxidation and aluminum sputtering reactions were predominant over the chlorination in strong CCl₄ plasmas operated at discharge currents of more than 75 mA. The chlorination initiated by the mild CCl₄ plasma was restricted near the film surface within 36 Å deep. The regions modified with the strong CCl₄ plasma reached inner layers of 36-49 Å deep. Hydrophilicity caused by the CCl₄ plasma treatment may be due not only to chlorine functionalities but also to oxygen and aluminum functionalities. © 1993 John Wiley & Sons, Inc.     

Evaluation for distance learning scheme on distributed multiple server system

A distributed multiple server system is designed and implemented with Web-DB based services for distance learning as well as emergency communication. The system has employed multiple servers located in a distributed campus network environment. Each server of the system has multi-core processors. With so-called “server virtualization” technology, some programs are executed in parallel (on the virtual servers) so that such a system can efficiently perform several functions. For example, two or more application services can be performed simultaneously as “cloud services” on the whole system. The system can provide distance learning scheme for educational tool, at the same time it can also support Web-based surveillance facilities for emergency contact. With qualitative and quantitative approach, trial evaluation of system has been performed in some classrooms of distributed campus. And users can obtain some good results from the above evaluation.     

One-Step Synthesis of Luminescent Nanoparticles of Complex Oxide, Strontium Aluminate

An organic aqueous solution of metal acetylacetonate precursors was subjected to spray pyrolysis in order to fabricate SrAl₂O₄:Eu (SAO) nanoparticles. Non-agglomerated luminescent SAO nanoparticles, having a spherical shape with a size of 10–30 nm, were achieved in a single step, while only submicrometer-sized SAO particles were obtained from the conventional ultrasonic pyrolysis of the metal nitrates. Without any post-annealing process, the as-prepared SAO nanoparticles were observed to exhibit a strong photoluminescence, which is comparable with that of the submicrometer-sized SAO particles. A mechanism for the formation of the nanoparticles is also discussed.     

Synthesis and luminescence properties of Pr3+ doped CaxBa1?xTiO3 (0.3?x<1) fine particles

Ca _x Ba_1−x TiO₃ (CBT) fine particles doped with red luminescence center of Pr³⁺ ions (Pr: CBT) were successfully synthesized by salt assisted spray pyrolysis (SASP) process. Scanning electronic microscope (SEM) and laser scattering analysis demonstrate that salt can be removed from the surface of particles by washing with Milli-Q water and the particles can be further separated by ball-milling to get well-dispersed Pr³⁺ ions doped CBT fine particles. The luminescence properties, such as photoluminescence (PL) and mechanoluminescence (ML), of as-synthesized Pr: CBT particles were investigated. For Pr: CBT fine particles with different Ca molar ratios, all the samples show one emission at 612 nm, with increasing Ca molar ratio, PL intensity of Pr: CBT fine particles become stronger and stronger. When pressure was loaded on the Pr: CBT pellet, mechanoluminescence(ML) emission was measured. The results show that the ML intensity is proportional to the applied pressure.     

Some characteristics of a sparged agitated vessel under foaming — Mechanical control of foaming —

Foam-breaking with a rotating disk mechanical foam-breaker (MFRD) was studied for a foaming system containing a diluted detergent solution in a laboratory sparged agitated vessel. The change of the foam-breaking capacity of the MFRD by varying the air sparge rate, the working volume and the impeller speed or the disk diameter was measured. Based on these measurements, empirical equations are presented for predicting the critical foam-breaking regions of the MFRD fitted with the agitated vessel. The operational range where foam-breaking with the MFRD can be carried out effectively and economically is also discussed.     

Measurement of self-diffusion coefficients in Li ionic conductors by using the short-lived radiotracer of 8Li

For the effective use of short-lived radioactive beams, soon to be available at the Tokai Radioactive Ion Accelerator Complex, the authors have developed a radiotracer method for diffusion studies in solids. The experimental test was performed by the measurement of the diffusion coefficients of Li in a sample of the compound βLiAl using an α-emitting radiotracer of ⁸Li (T_1/2=0.84 s). It was found that the time-dependent yields of the α particles from the diffusing ⁸Li that was initially implanted in the sample could be used as a measure of the diffusivity of the tracer in a nondestructive way. The method was applied to measure the self-diffusion coefficients of Li in βLiGa, and for investigating how the Li diffusion in the Li ionic conductors is affected by the concentration of atomic defects (i.e., the existence of the atomic vacancies of Li and the defects in Ga sites that are replaced by Li).     

A 78-year-old man with young onset parkinsonism and sudden death

We report a right-handed 78-year-old man with early onset parkinsonism. The patient had an onset of micrographia at 23 years of the age in 1939. Seven years later he started to drag his right foot, and at 38 years of age, he walked with small steps with festination. Tremor was also present in his right hand. His daily life was independent as a otorhinolaryngologist. He visited our clinic on March 24, 1977 when he was mentally sound and showed mild parkinsonism consisting of masked face, stooped posture, small step gait, bradykinesia, and right side dominant rigidity and tremor. He showed good response to trihexyphenidyl and amantadine HCl. Two month later, he developed dyskinesia and some worsening of parkinsonism, and was admitted to our hospital for the first time. He was treated with 400 to 600 mg/day of levodopa/ carbidopa. He showed marked improvement, however, dyskinesia remained in his mouth. He was doing well until 77 years of age (June of 1993) when he developed hallucination and motor fluctuations. He was admitted again to our hospital on June 22, 1993. On admission, he was alert and appeared mentally sound. However, Hasegawa dementia scale was 18/30. Upward gaze was slightly restricted (3/5). Voice was somewhat small but no masking was noted. His posture was stooped and the gait was of small step. Dyskinesia was noted during walk. No rigidity nor tremor was noted. Deep tendon reflexes were lost but no sensory loss or motor weakness was noted. Routine laboratory studies were unremarkable. A cranial CT scan revealed only mild to moderate cortical atrophy. Motor and sensory conduction velocities were within normal limits, however, motor action potentials could not be obtained with stimulation to the right common peroneal nerve. He was treated with 600 mg/day of levodopa with carbidopa, 100 mg of amantadine HCl, 300 mg of Dops, and 25 mg of tiapride. He continued to show motor fluctuations, and was discharged on July 23, 1993. Since then his motor functions had become progressively worse with frequent falls, but he was still able to walk without support. On October 3 of 1994, he went to bed as usual. On the next morning, he was found dead in his bed at 9: 30. The patient was discussed in neurological CPC, and the chief discussant arrived at the conclusion that the patient had young-onset Parkinson's disease with Lewy bodies in the substantia nigra. Opinions were divided between Parkinson's disease and Lewy body negative young onset parkinsonism. Postmortem examination revealed obstruction of the trachea by aspirated foods, and the cause of death appeared to have been suffocation by the foods. Macroscopically, the external appearance of the brain was unremarkable except for slight frontal atrophy. The substantia nigra showed depigmentation in the lateral part, but the pigmentation of the medial part was well preserved. Upon histologic examination, the number of pigmented neurons in the dorsomedial part was well preserved. In the lateral part, pigmented neurons were well preserved in the dorsal area, however, in the ventral area, only non-pigmented neurons were seen; they appeared to be neurons in the pars reticulata. No gliosis was seen in any of the nigral areas. No Lewy bodies were seen in the remaining neurons. So-called immature neurons with rounded shape without neuromelanin could not be detected. The locus coeruleus neurons were well preserved. The putamen and the other basal ganglia structures were also intact. Slight myelin pallor was noted in the subcortical white matter, however, otherwise cerebral cortices were normal. The histology of this patient is unique in that only the ventrolateral part of the substantia nigra showed abnormal finding consisting of lack of pigmented neurons without gliosis. It is not clear whether the nigral change represents degeneration or a congenital "hypoplasia'. To our knowledge, such a unique pathology of the substantia nigra has not been reported in the literature. Our patient ma     

Survey of actual viewing conditions at home and appropriate luminance of LCD‐TV screens

Abstract— To understand actual viewing conditions at home is important for TV design. And the preferred luminance level of LCD TVs under actual viewing conditions is also important in order to obtain both good picture quality and low power consumption. The actual viewing conditions of households and the preferred luminance levels was investigated. In a field test of 83 households, the display luminance, screen illuminance, and viewing locations were measured on site. In laboratory experiments, young and elderly subjects adjusted the luminance of an LCD‐TV screen to their preferred levels under different screen illuminance levels, angular screen sizes, and average luminance levels (ALL) of the images. As a result, two equations, which represent the preferred luminance level of LCD‐TV screens corresponding to different viewing conditions for young and elderly subjects were obtained. When the ALL of the images was 25% and the screen illuminance and angular screen size were set at 100 lx and 20°, respectively, the preferred luminance was 1 60 cd/m² for the young subjects and 248 cd/m² for the elderly subjects. By using the setting of the preferred luminance of an LCD TV under actual viewing conditions, it is possible to conserve energy consumption.