Efficient hydrogen production using a multi-layered photobioreactor and a photosynthetic bacterium mutant with reduced pigment

A multi-layered photobioreactor (MLPR), where the light paths were formed by the localization of bacterial cells, was constructed for efficient hydrogen production. The performance was investigated under several conditions in order to clarify the effect of this reactor on hydrogen production. An analysis of the hydrogen production profile showed that the MPLR utilizes both the light that directly illuminates its surface and the light induced and diffused from its light paths for hydrogen production. It was also found that the hydrogen productivity in the MLPR was more than twice that in a plate-type reactor. When a photosynthetic bacterium mutant with reduced pigment, MTP4, was used, the maximum hydrogen production rate reached 2.0 l/m² h, which was 38% higher than that of a conventional plate-type reactor. The synergistic effect of the improvement in the reactor and the modification of the bacteria was brought about by the combination of the MLPR and MTP4, and resulted in an improvement in the hydrogen production.     

Intra-arterial preventive chemotherapy for residual liver after resection of hepatic metastasis from colorectal cancer

We treated 18 cases with intra-hepatic arterial infusion chemotherapy after resection of hepatic metastasis from colorectal cancer (June 1991-September 1997). Eight cases were H1, 7 were H2, and 3 were H3. Hepatic lobectomy was done in 3 cases, lobectomy + partial resection in 2 cases, and partial resection in 13 cases. All cases received high-dose intermittent 5-FU infusion (WHF = 5-FU 1,000 mg/m2/5 hrs/w) on an outpatient basis. The total frequency of WHF was 4-54 times (average 29), and total 5-FU doses ranged from 6.0 to 81.0 g (average 40 g). The 1- and 5-year cumulative survival rates were 100% and 77.5% in all patients 100% and 87.5% in H1 group and 100% and 64.3% in H2 + H3 group, respectively. There was no significant difference of survival between the H1 and H1 + H3 groups. The 1- and 5-year recurrence rates in residual liver were 5.9% and 14.4%, respectively. One of 2 cases with residual liver recurrence was resected for metastasis again, and the patient is now in a disease-free state. WHF after resection of hepatic metastasis from colorectal cancer has a preventive effect for their survival, not only in H1 group but also in H2 + H3 group.     

Oxidation products of cyanidin 3-O-β-d-glucoside with a free radical initiator

Recently, we have reported that anthocyanins show strong antioxidative activity, but no attention has been paid to anthocyanins from the viewpoint of the reaction mechanism of alkylperoxyl radicals; therefore, we investigated the reaction products of antioxidative anthocyanins (cyanidin 3-O-β-d-glucoside). Cyanidin 3-O-β-d-glucoside was reacted with 2,2′-azobis(2,4-dimet hylvaleronitrile) to generate the alkylperoxyl radicals, and the reaction products were isolated by high-performance liquid chromatography. The products were identified as 4,6-dihydroxy-2-O-β-d-glucosyl-3-oxo-2,3-dihydrobenzofuran and protocatechuic acid. Based on reaction products, the antioxidative mechanism of cyanidin 3-O-β-d-glucoside may be different from that of α-tocopherol; cyanidin 3-O-β-d-glucoside would produce another radical scavenger, as it would break down the structure and scavenge the radicals.     

Integrated circuits for television receivers

Integrated circuits are being investigated for use in as many television circuits as feasible. In Japan, considerable work has been done by different groups within the TV industry to develop ICs that will permit cost reduction, increased reliability, and simplification of assembly-line operations. This article is a report on results of the concentrated efforts made by five major television set manufacturers to develop and produce black-and-white and color receivers, in collaboration with four universities, two institutes, and seven components manufacturers.     

Morphology of composite film prepared by polymerizing styrene in poly(vinyl chloride) film

Styrene and the styrene-additive mixtures (kerosene, dioxane, ethylene dichloride, or dioctylphthalate) were soaked into a poly(vinylchloride) film and then styrene was polymerized. Subsequently, poly(styrene) was extracted with CCl₄ and the microporous membrane was obtained, of which the morphology was studied. It is elucidated that the additives affect the morphology of the resultant composite films.     

Lead Oxide Coatings on Sol–Gel-Derived Lead Lanthanum Zirconium Titanate Thin Layers for Enhanced Crystallization into the Perovskite Structure

An improved method is described for the sol–gel preparation of PLZT thin layers in the perovskite structure. The method uses a PbO cover coat. Details are reported for the sol-gel processing route and heat-treatment conditions. Through use of this method it is possible to prepare singlephase perovskite material with improved properties. The deleterious effect of additional phases—which are not present when a PbO cover coat is used—is attributed to Pb loss from the surface during thermal processing. Examples are given for PLZT thin layers integrated on Si with and without a PbO cover coat. The dielectric and ferroelectric properties were always found to be superior for coated structures.     

Structural and electrical studies of plasma-deposited polycrystalline silicon thin-films for photovoltaic application

Plasma-deposited polycrystalline Si films [or microcrystalline Si (μc-Si) films] produced by plasma enhanced chemical vapor deposition (PECVD) have attracted considerable attention as novel, low-cost and stable materials for the photovoltaic i-layer in p–i–n junction thin-film solar cells. The μc-Si films prepared under various deposition conditions show widely various microstructures, from a crystalline–amorphous mixed state to an almost perfect crystalline state, with different crystallographic orientations. These structural changes directly influence the carrier transport properties that play a dominant role in determining photovoltaic performance. Furthermore, obtaining a uniform built-in electric field throughout the i-layer is a crucial issue for achieving excellent photovoltaic performance. To obtain a uniform electric field, the following terms should be required for the i-layer: ‘truly’ intrinsic characteristic (or not n-type characteristics) as well as structural uniformity in the growth direction without an incubation layer. Here, structural properties of μc-Si for achieving truly intrinsic characteristics are reviewed with an emphasis on collations with the crystalline volume function and the degree of (2 2 0) crystallographic preferential orientation in the crystalline phase. In addition, we reviewed a growth mechanism for the μc-Si film that is actually used in the photovoltaic i-layer in highly efficient solar cells: hybrid-phase growth consisting of conventional vapor-phase growth at the surface and the solid-phase crystallization that simultaneously occurs in the film. That growth is very effective in producing structural uniformity along the growth direction and for formation of crystallites directly on the underlying doped layer.