Partial removal of PCDD/Fs, coplanar PCBS, and PCBS from municipal solid waste incineration fly ash by a column flotation process

Municipal solid waste incineration (MSWI) fly ash has recently attracted much attention because of its large quantity and enrichment of high toxic combustion generating organohalogen contaminants such as polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), coplanar polychlorinated biphenyls (coplanar PCBs), and polychlorinated biphenyls (PCBs). Since the organohalogen contaminants in MSWI fly ash are known to be enriched in the unburnt carbon (UC) fraction, the organohalogen contaminants can therefore be removed by the removal of UC. In this research, we used a modified column flotation technique to remove the organic contaminants from MSWI fly ash. UC was removed for 27.7% under the flotation condition without chemical flotation aids. The removal efficiencies of UC, PCDD/Fs, coplanar PCBs, and PCBs are further improved by adding flotation aids during the flotation process. UC was removed for 49.0% by adding a collector assistant with a HLB value of 13.5 and a concentration in the kerosene of 3% during the flotation process. In addition,the UC removal efficiencies are increased with the decrease of the diameter of the micropores in the gas spargers. By optimizing the flotation condition, 41.9% total PCDD/Fs, 40.8% coplanar PCBs, and 44.1% PCBs with 64.0% UC have been successfully removed from MSWI fly ash. The total toxic equivalent (TEQ) of the fly ash was decreased from 6.2 ng/g to 4.2 ng/g in the residue.     

Optical properties of epitaxial plzt thin films

In the epitaxial (Pb_1?x , La _x )(Zr_1?y , Ti _y )_1?x/4O₃ [PLZT] films, the composition dependence of the refractive index and electric-optic (EO) coefficient near the morphotropic phase boundary (MPB) composition was investigated. A (100/001)-oriented PLZT 10/65/35 epitaxial film is found to have isotropic optical properties. Highly (100/001)-oriented epitaxial PLZT films with compositions near the MPB on Nb–SrTiO₃ substrates were fabricated using a sol–gel process. The value of birefringence from 4?×?10^?3 to 5?×?10^?4 in PLZT epitaxial film was smaller than that of lithium niobate single crystal. The refractive index decreases with increasing lanthanum content. The difference in the refractive index obtained depended upon the lanthanum content up to 2%. This value is adequate for fabrication of waveguide structures. The EO coefficient of PLZT 9/65/35 thin films was 45 pm/V, which is larger than that of lithium niobate single crystal. A very small polarization dependence of the EO coefficient was also observed.     

Activity of chromium oxide and phase relations for the CaO-SiO2-CrOX system at 1873 K under moderately reducing conditions

In order to optimize the slag composition operated in the decarburization process of stainless steel production, activity of chromium oxide, aCrO_X, and phase relations for the CaO-SiO₂-CrO_X system have been investigated under moderately reducing conditions, P_O2 = 7.04?10^{? 6}Pa at 1873 K. Activity coefficients of chromium oxides show strong dependencies on X_CaO/X_SiO2, an index of basicity, and chromium content of the slag. Solubility of chromium oxide in the slag system drastically decreases with increasing X_caO/X_SiO2, which is consistent with increase in activity coefficients of chromium oxides. The optimal CaO-SiO₂-CrO_X slag for a practical decarburization process has been recommended to be doubly saturated with CrO_1.5 and CaCr₂O₄, namely XCaO/XsiO₂ = 1.47 at 1873 K, which may not be significantly affected by operating temperatures.     

Amniotic LPS-Induced Apoptosis in the Fetal Brain Is Suppressed by Vaginal LPS Preconditioning but Is Promoted by Continuous Ischemic Reperfusion

Chorioamnionitis (CAM) is an increasingly common disease affecting pregnant women which derives from bacterial vaginosis. In different clinical cases, it has been shown that CAM can cause multiple risk factors for fetal brain damage, such as infection, and intra-uterine asphyxia. However, the molecular mechanism remains unknown. In this study, we established a novel CAM mouse model by exposing pregnant mice to a combination of three risk factors: vaginal lipopolysaccharides (LPS), amniotic LPS, and ischemic reperfusion. We found amniotic LPS caused Parkinson’s disease-like fetal brain damage, in a dose and time-dependent manner. Moreover, the mechanism of this fetal brain damage is apoptosis induced by amniotic LPS but it was inhibited by being pretreated with a vaginal LPS challenge before amniotic LPS injection. In contrast, amniotic LPS with continuous ischemic reperfusion caused a higher level of apoptotic cell death than amniotic LPS alone. In particular, a potential neuroprotective biomarker phosphorylation (p)-CREB (ser133) appeared in only vaginal LPS preconditioned before amniotic LPS, whereas ischemic reperfusion triggered IKK phosphorylation after amniotic LPS. Despite the need for many future investigations, this study also discussed a developed understanding of the molecular mechanism of how these phenotypes occurred.     

Liquefaction and product identification of corn bran (CB) in phenol

The liquefaction of corn bran (CB) was successfully conducted by using three different liquefaction conditions. Among them, catalyzed liquefaction at high pressure and temperature (180–220°C) using phenol was the most effective for the liquefaction of CB. Both the phenol/CB ratio and the catalyst content affected the extent of the liquefaction. The decomposed components of CB did not show high reactivity toward phenol when liquefied without a catalyst. Thermal‐flow properties of the phenolated CB and flexural properties of the phenolated CB‐based moldings were influenced by the amount of combined phenol and were comparable to those of the commercial novolak or phenolated wood. The effect of molding time and filler content on the flexural properties is also presented. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 311–318, 2000     

Novel ambient temperature curable two-component waterborne silicone-acrylic coatings

Waterborne coatings are composed of resins containing hydrophilic functional groups. These groups usually remain in the coating film and can adversely affect film properties such as weatherability and resistance to water and alkali. We have developed a novel ambient temperature curable waterborne two-component system, in which the hydrophilic functional groups are consumed by the crosslinking reaction. The new coating system consists of a waterborne acrylic resin containing both tert-amino and carboxylic acid groups and a hardener containing both epoxy and alkoxysilyl groups. The waterborne silicone acrylic coatings provide superior film properties even if the acrylic resin has relatively low functional group content. In this paper we describe the crosslinking reaction mechanism and film properties using some acrylic resin types and paint formulations as examples. Presented at the 24th Annual Waterborne, High-Solids, and Powder Coatings Symposium, on February 5–7, 1997, in New Orleans, LA. 1-3 Takasago, Takaishi-shi, Osaka, Japan.     

Relationship between magnetic poles and characteristics of revolving permanent‐magnet type magnet wheels

The authors earlier proposed a revolving permanent‐magnet type wheel called the “magnet wheel,” which has the functions of both induction repulsive magnetic levitation and thrust. In this paper, the relationship between magnetic poles and lift force or thrust characteristics is examined to investigate the performance. Five types of magnet wheels are discussed in an experimental study and four more types are used in a theoretical study with three‐dimensional numerical analysis. The following parameters are considered: magnetomotive force (mmf) of a permanent magnet; thickness of the magnet in the magnetizing direction; total volume of magnets; fundamental factor; distortion factor of the space mmf distribution of poles; pole pitch; diameter of magnet wheel; mechanical clearance; and thickness and resistivity of conducting plate. The results show the following: 1. The lift force per unit of magnet volume is approximately proportional to the fundamental factor of the space mmf distribution of the poles. A low degree space harmonic mmf is effective in increasing lift force. 2. The driving power per unit of lift force is almost entirely independent of the configuration of the primary member, including pole arrangement and position relative to the secondary conducting plate, respectively, and depends only on the resistance of the conducting plate. 3. In both the “partial‐overlap type” and “tilt type” magnet wheels, many poles with sufficiently large pole pitch are useful. In the tilt type the use of a small tilt angle is desirable. © 1999 Scripta Technica, Electr Eng Jpn, 128(4): 111–120, 1999     

Poly(vinyl alcohol)-clay and poly(ethylene oxide)-clay blends prepared using water as solvent

Montmorillonite (MON) was solvent-cast blended with poly(vinyl alcohol) (PVA) and poly(ethylene oxide) (PEO) using water as cosolvent. The structure and properties of the blend films have been investigated. From small- and wide-angle X-ray scattering measurements of the blends, the silicate layers of MON are found to be well dispersed individually in the PVA-MON blends, while the silicate layers in PEO-MON blends are found to exist in the form of a large clay tactoid. Furthermore, for both blends, it is found that the silicate layers are parallel to the film surface of the blends, and that preferred orientation of polymer crystallites is induced by the presence of MON. The effects of the MON content on the thermal behavior of the PVA- and PEO-MON blends have been studied with a differential scanning calorimeter. Furthermore, the effects of geometry of the silicate layers on dynamic behavior of the blends have been studied. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 573–581, 1997     

Regulation of peroxisomal proteins and organelle proliferation by multiple carbon sources in the methylotrophic yeast,Candida boidinii

A methylotrophic yeast, Candida boidinii, was grown on various combinations of peroxisome-inducing carbon source(s) (PIC(s)), i.e. methanol, oleate and d-alanine, and the regulation of peroxisomal proteins (both matrix and membrane ones) and organelle proliferation were studied. This regulation was followed (1) at the protein or enzyme level by means of the peroxisomal enzyme activity and Western analysis; (2) at the mRNA level by Northern analysis; and (3) at the organelle level by direct observation of peroxisomes under a fluorescent microscope. Peroxisomal proliferation was followed in vivo by using a C. boidinii strain producing a green fluorescent protein having peroxisomal targeting signal 1. When multiple PICs were used for cell growth, C. boidinii induced specific peroxisomal proteins characteristic of all PIC(s) present in the medium, responding to all PIC(s) simultaneously. Thus, these PICs were considered to induce peroxisomal proliferation independently and not to repress peroxisomes induced by other PICs. Next, the sensitivity of the peroxisomal induction to glucose repression was studied. While the peroxisomal induction by methanol or oleate was completely repressed by glucose, the d-alanine-induced activities of d-amino acid oxidase and catalase, Pmp47, and the organelle proliferation were not. These results indicate that peroxisomal proliferation in yeasts is not necessarily sensitive to glucose repression. Lastly, this regulation was shown to occur at the mRNA level. © 1998 John Wiley & Sons, Ltd.     

Development for 4th generation mobile communications

The great success of the i‐mode service shows that data communication services are becoming accepted in the mobile communication world. Multimedia mobile communication services will be provided by 3rd generation IMT‐2000 systems next year in Japan. Thus, the time has come to begin the research and development for 4th generation (4G) mobile communication systems. There exist many difficult issues for 4G systems, such as frequency resources, additional investment, higher speed wireless transmission technology and so on. Furthermore, a new concept must be discussed for 4G before solving these issues. This paper briefly presents current conditions of cellular systems and the development of IMT‐2000 in Japan. The concept and problems of the 4G system are then described along with new technologies that will be useful in solving technical problems. Copyright © 2001 John Wiley & Sons, Ltd.