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The objective of this study was to investigate the lab-scale manufacturing process of insulation fiberboard (IFB) with cellulose nanofibers (CNFs) and evaluate the effects of CNFs on the mechanical and physical properties of the IFB. Because the fabricated IFBs with CNFs had a homogeneous appearance, it was assumed that CNFs can be easily dispersed within IFB by adding them during the mixing stage of the wet process of wood-based board production. The results for the IFBs with CNFs revealed that the density and bending properties increased, while the thickness decreased with an increase in the CNF addition ratio. Furthermore, after the water absorption test, the weight change rates of the IFBs decreased, and the thickness swelling rates increased. Although the size of the specimens was different from the size in JIS A 5905 (Japan Standards Association 2014), the modulus of rupture (MOR) values of IFBs with a target density more than or equal to 0.20 g/cm3 were higher than the value of A-class IFB in the standard for all CNF addition ratios. In addition, lower thermal conductivity may be realized under similar MOR values by adding CNFs to IFB. On the other hand, to produce CNF-reinforced IFBs with target density/thickness, it is necessary to develop a method for decreasing the cohesive force derived from CNF aggregation and the compressive force originating from the water surface tension caused by the high water retention of CNFs.

This paper presents the first-principles investigation on interfacial adhesive strength between grafted polymer and cellulose. Focusing on maleic anhydride-grafted polypropylene, which is expected to be used in various applications including automobiles, a simple interfacial model was constructed under a local tensile loading condition. Then the stress–strain relation, deformation of molecular structure and breaking process were discussed. From comparison of mechanical responses among three chemically possible bonding configurations, it was clarified that the monoester bond exhibited higher interfacial strength than the diester bond. We also found that controlling the bonding configuration can improve the interface strength by about 50% compared to when primary OH groups react to form ester bonds. It was proved that this first-principles calculation model was effective for the definitive design and development of chemical modification of nanocellulose.

The addition of maleic anhydride (MA)-modified polypropylene (MAPP) as a compatibilizer increases mechanical and physical properties of wood/plastic composites (WPCs). It is thought that MA graft ratio (Gr), molecular weight (weight-average molecular weight [Mw]), and mixing methods of MAPP affect physical and mechanical properties of WPCs. However, evaluation, especially for mixing order, is not enough. The objective of this study was to investigate the effect of Gr and Mw of MAPP and its mixing methods on the mechanical and physical properties of WPCs. Two types of mixing methods were used: mixing the MAPP with the filler using a Henschel mixer before kneading with PP (premixing method) and mixing all of the materials at one time (one-step mixing method). The WPCs made with the premixing method had lower shear viscosity and higher flexural modulus than those made with the one-step mixing method. The particle size, moisture content, and surface morphology of fillers are thought to be more important in determining the shear viscosity of WPCs than the MAPP itself. The highest tensile, impact, and flexural strengths of WPCs were obtained in the WPC with premixing with low-Gr and high-Mw MAPP. It may be due to the effective reaction of the wood flour with MAPP and higher entanglement between the MAPP and PP. These results suggest that the premixing method could improve productivity and mechanical properties of WPCs.

To realize upgrade recycling of commodity-type polyolefin resins, acid modification with maleic anhydride (MAH) and organic peroxide was applied to polypropylene (PP)-rich commercial recovered resi...

Compatibilizers added into filler-reinforced polymer composites are supposed to bring about the enhancement of mechanical properties by binding with the filler and entanglement with the polymer matrix. We elucidated the binding of maleic anhydride-modified polypropylene (MAPP) compatibilizer and microcrystalline cellulose (MCC) filler. This is usually not readily detectable by spectroscopy. For this, we adopted a set of enzymatic digestion and refined but simple spectroscopy. A series of binary composites of MCC and MAPP was prepared by kneading. By the cellulolytic treatment and an adequate heat processing, we obtained clear IR signals due to the binding. Furthermore, by gel (swollen)-state NMR method which has attracted attention for analyzing plant cell wall, we acquired interface-specific liquid-state NMR spectra giving the information of the bonds between these components insoluble in commonly used solvents. Such analytical methods provide a useful perspective on the relationship between the microstructure and compatibility of composite materials.

Commercial wood flour of pine (Pinus densiflora) was used as an experimental material. It was milled with different milling times 0, 10, 20, 30, 40, 60, and 120 min to investigate the effect of their particle size distribution on the mechanical properties of the wood–plastic composite. Two kinds of drying conditions, 7 days of freeze-drying at a temperature of −45 °C and heat drying (80 °C) for 24 h were applied. Polypropylene and maleic anhydride-grafted polypropylene were used as a matrix and the compatibilizer of the wood–plastic composite compound, respectively. Particle size analysis showed that an increase in the time of ball milling decreased the wood flour size. However, an excessive milling period of time longer than 40 min corresponded to an increase in the amount of aggregation. Scanning electron microscope images showed the existence of aggregation for the wood flour with 120 min of wet milling time. As the particle size decreased, mechanical properties of wood–plastic composite increased for up to 30 min of wet milling time and then slightly decreased. This behavior might be due to aggregation. The optimum mechanical property was obtained at 30 min of wet milling time under freeze-drying conditions.

Recently, the usage of wood–plastic composite (WPC) products has increased, mainly for exterior decking. The shape of fillers is one of the important factors deciding the mechanical and ph...

A nitrate-reducing bacterium was isolated from a hot spring and identified as Bacillus licheniformis. This strain was found to accumulate NO2(-) in the medium even in the presence of NH4(+) by shaking culture when FeSO4 was added to the medium. The NO2(-) accumulation was due to nitrate reductase activity, and the same accumulation was also recognized in some other bacteria. Since the nitrate reduction had no marked effect on the cell growth, it is possible that this nitrate reduction may not be involved in either an assimilatory or a dissimilatory one like those hitherto reported.

High performance liquid chromatography (HPLC) analysis of the culture filtrate of an isolated mold, Aspergillus terreus S-4, showed a larger peak of a terrein-like substance than those of gallic acid and protocatechuic acid. The chemical structure of this substance was investigated and identified as terrein, 4,5-dihydroxy-3-propenyl- 2-cyclopenten-1-one. We also examined some culture conditions for the production of terrein using a sake cake medium for strain S-4.

Background Katsuobushi is a dried, smoked and fermented bonito used in Japanese cuisine. During the fermentation process with several Aspergillus species, the colour of Katsuobushi gradually changes from a dark reddish-brown derived from haem proteins to pale pink. The change in colour gives Katsuobushi a higher ranking and price. This study aimed to elucidate the mechanism of decolourisation of Katsuobushi. Results A decolourising factor from the culture supernatant of Aspergillus (Eurotium) repens strain MK82 was purified to homogeneity. The purification was monitored by measuring the decolourising activity using equine myoglobin and bovine haemoglobin as substrates. It was found that the decolourising factor had protease activity towards myoglobin and haemoglobin. Complete inhibition of the enzyme by the inhibitor pepstatin A and the internal amino acid sequence classified the protein as an aspartic protease. The enzyme limitedly hydrolysed myoglobin between 1-Met and 2-Gly, 43-Lys and 44-Phe, and 70-Leu and 71-Thr. The purified enzyme decolourised blood of Katsuwonus pelamis (bonito) and a slice of dried bonito. Conclusion It is proposed that aspartic protease plays a role in the decolourisation of Katsuobushi by the hydrolysis of haem proteins that allows the released haem to aggregate in the dried bonito.

Optical properties, including optical transmittance, absorption coefficient, refractive index, and dielectric constant, of Sr7%, Ce15% co-doped GdF 3 crystal grown by the Czochralski method are discussed. Moreover, α-ray responses, including emission spectrum, pulse height spectrum, and decay time, are also presented. This is the first report on refractive index, dielectric constant, and light yield under α-ray irradiation of the Sr:Ce:GdF 3 single crystal.

In this study, (Gd1−xYx)F3 (x=0.2, 0.4, 0.5 0.6 and 0.8) crystals were grown by the μ-PD method. Neither visible inclusions nor cracks were observed in (Gd1−xYx)F3 (x=0.4, 0.5 and 0.6) crystals. Lattice constants increase linearly as the Y3+ concentration decreases. Using (Gd1−xYx)F3 as a host material, the Sr0.5% Ce1%, 3%, 5% and 7% co-doped Gd0.5Y0.5F3 single crystal was prepared. In this crystal, Ce3+-perturbed luminescence at 380 nm is observed with 31.8 ns photoluminescence decay time. Under X-ray excitation rather high radioluminescence intensity of this band was obtained exceeding that of BGO scintillator. The energy transfer in the sequence of regular Ce3+→ (Gd3+)n→ perturbed Ce3+ sites was evidenced though observation of decay time shortening of the regular Ce3+ and Gd3+ centers and intensity change between Gd3+ and Ce3+-perturbed emission.

Photoreorientation of a stripe pattern consisting of an MPS structure in a Langmuir-Blodgett monolayer by irradiation with linearly polarized light is achieved for the first time using a PDMS/poly(methacrylate) diblock copolymer with a liquid crystalline azobenzene-containing side chain. The stripe MPS pattern in the trans azobenzene state is diminished by photoisomerization to the cis form upon UV light irradiation. By the erasure of the MPS structure, the anisotropic photo-oriented stripe pattern is generated upon irradiation with linearly polarized visible light, the orientation of the stripe pattern being orthogonal to the electric vector of the light.

Pr1%:K(Y 1− x Lu x ) 3 F 10 ( x =0, 0.2, 0.4) single crystals were grown by the μ-PD method. All the grown crystals were greenish and perfectly transparent without any inclusions or cracks. Radioluminescence spectra and decay kinetics of the Pr1%:K(Y,Lu) 3 F 10 crystals were measured. Emission from the Pr 3+ 5d–4f transition, peaking around 260 nm and of the decay time of around 22 ns were observed. The 5d–4f emission intensities of the Pr1%:K(Y,Lu) 3 F 10 crystals were higher than that of the standard BGO scintillator.

A recombinant cyclodextrin glycosyltransferase (CGTase) gene fused with thioredoxin (Trx), hexa-histidine (His(6)) and S-protein (S) at the N terminus and a proline-rich peptide (PRP) at the C terminus, was constructed using the wild-type gene from Paenibacillus sp. A11, the pET-32a vector and Escherichia coli BL21(DE3) as the host cell. The expression levels and enzyme characteristics of the Trx-His(6)-CGTase-PRP fusion protein, the recombinant CGTase without fusion peptides, and the wild-type CGTase were compared. The maximum specific activity for the Trx-His(6)-CGTase-PRP fusion enzyme was 2.7 fold higher than that of the non-fusion form at the optimal IPTG concentration. The Trx-His(6)-CGTase-PRP fusion protein was purified to homogeneity by starch adsorption and Ni-NTA affinity chromatography, with a specific activity of 2,268 units/mg protein at a 61% yield. The ease of purification and the higher enzyme yield were obtained with the fusion form when compared to the non-fusion and wild-type enzymes. The fusion enzyme was superior than its wild-type counterpart in terms of stability against high temperature and organic solvents. Moreover, the fusion enzyme could catalyze the synthesis of cyclodextrins in 20% (v/v) dimethylformamide with a higher product yield of CD(7) and CD(8) compared to that of the wild-type enzyme in the same buffer-solvent system.

Burkholderia sp. strain AK-5 converts 4-aminophenol to maleylacetic acid via 1,2,4-trihydroxybenzene, which is unstable in vitro and non-enzymatically auto-oxidized to 2-hydroxy-1,4-benzoquinone. Crude extract of strain AK-5 retarded the auto-oxidation and reduced the substrate analogue, 2,6-dimethoxy-1,4-benzoquinone, in the presence of NADH. The two enzymes responsible were purified to homogeneity. The deduced amino acid sequence of the enzyme that inhibited the auto-oxidation showed a high level of identity to sequences of iron-containing superoxide dismutases (Fe-SODs) and contained a conserved metal-ion-binding site; the purified enzyme showed superoxide dismutase activity and contained 1 mol of Fe per mol of enzyme, identifying it as Fe-SOD. Among three type SODs tested, Fe-SOD purified here inhibited the auto-oxidation most efficiently. The other purified enzyme showed a broad substrate specificity toward benzoquinones, including 2-hydroxy-1,4-benzoquinone, converting them to the corresponding 1,4-benzenediols; the enzyme was identified as 2-hydroxy-1,4-benzoquinone reductase. The deduced amino acid sequence did not show a high level of identity to that of benzoquinone reductases from bacteria and fungi that degrade chlorinated phenols or nitrophenols. The indirect role of Fe-SOD in 1,2,4-trihydroxybenzene metabolism is probably to scavenge and detoxify reactive species that promote the auto-oxidation of 1,2,4-trihydroxybenzene in vivo. The direct role of benzoquinone reductase would be to convert the auto-oxidation product back to 1,2,4-trihydroxybenzene. These two enzymes together with 1,2,4-trihydroxybenzene 1,2-dioxygenase convert 1,2,4-trihydroxybenzene to maleylacetic acid.

Liquified Natural Gas (LNG) is one of the most promising propellant for near future space transportation rocket engine because of its low cost and fewer handling concerns. However, for LNG propellant, erosion of engine material by sulfur (sulfur attack) and coking by LNG pyrolysis are significant problems in a regenerative cooling passage. In this study, the effects of sulfur attack and coking are experimentally evaluated for material candidates such as Inconel600, SUS316, Hastelloy-X, and some copper alloys. In the sulfur attack tests, EPMA and Raman analysis indicate that metallic sulfide can be observed only on the surface and XRD analysis indicates that sulfur attack are hardly recognized for all of material in the test conditions. In coking tests, it is clear that coking of methane with 5% propane can proceed more than those of pure methane. The thermal decomposition temperature is significantly decreased by catalytic effects of Ni in engine material. The results of coking tests will be included in the design criteria of combustion chamber, nozzle of the LNG rocket engines.

A newly isolated strain, MS-2-5, identified as Bacillus halodurans , produced five alkaline and thermotolerant amylases. The five amylases, named amylases A–E, were separated from each other, and purified to homogeneity. The molecular masses of these amylases were different from each other, and estimated to be 90, 85, 70, 65, and 58 kDa. These amylases showed the maximal activities at 60–65 °C and pH 10.5–11. A predominant product by each enzyme reaction was maltotetraose. These amylases were classified as an α-amylase by anomeric form analysis of the reaction products. Internal amino acid sequence analyses of the purified enzymes suggested that these enzymes were produced from a single polypeptide by proteolytic degradation. The gene, named amyA , was cloned and expressed in the T7 promoter systems of Escherichia coli . To increase yield and productivity of recombinant enzyme, cultivation conditions were examined. The maximal amount of enzyme was produced when an E. coli transformant carrying amyA was cultivated at 25 °C in Luria-Bertani medium supplemented with 1.0% d -glucose, 1.0% d -sorbitol, 0.1% MgSO 4 ·7H 2 O, and 2.0% yeast extract. The yield of the transformant increased 104-fold as, compared with that of the parent strain MS-2-5.

Ceriporiopsis sp. strain MD-1, isolated from forest soil, produced several extracellular enzymes that decolorized human hair melanin. Among them, three enzymes (E1, E2-1, and E2-2) were purified to homogeneity and characterized. The enzymes required hydrogen peroxide in their enzyme reactions and, typical of other fungal peroxidases, oxidized various phenol compounds such as guaiacol, but not 3,4-dimethoxybenzyl alcohol. The spectra of the three enzymes showed an absorption maximum at 406 nm, indicating that they were heme proteins. However, the A 406 / A 280 values of the enzymes were below 0.4, which was lower than those of other peroxidases. E2-1 and E2-2 were similar to each other in their molecular and catalytic properties, and they possibly represent products of posttranslational modifications and/or allelic variants of the same gene, mdcA . The corresponding cDNA was cloned and sequenced; the deduced amino acid sequence showed high identities to the manganese peroxidases from other microorganisms. The specific activities and K m values of E2-1 and E2-2 for synthetic and human hair melanins were much higher than those of Phanerochaete chrysosporium manganese peroxidase and lignin peroxidase.

Bacillus pumilus X-6-9 isolated from soil and subsequently identified, produced xylooligosaccharides with long chains from xylan and accumulated them in the culture. By improving the culture conditions and mutating the bacterium, a 3.2-fold increase in the production of the xylooligosaccharides was established, when compared to the original culture conditions of B. pumilus X-6-19. The addition of D-glucose to the culture of the mutant strain U-3 of B. pumilus X-6-9 repressed the synthesis of beta-xylosidase, but not xylanase. Thus, it was revealed that strain U-3 was a good organism for the production and accumulation of xylooligosaccharides with long chains from xylan by a microbial culture. Xylanase produced by strain U-3 was purified to homogeneity and characterized. The hydrolyzates generated by the purified xylanase contained xylobiose, xylotriose, xylotetraose, and xylopentaose, but not xylose.

The biodegradable chelating agents [S,S]-ethylenediaminedisuccinic acid (EDDS), citric acid and the low biodegradable chelating agent ethylenediaminetetraacetic acid (EDTA) were investigated for their applicability for the removal of lead from soil by soil washing and electrokinetic processing. In the soil washing tests at 298 K, the removal efficiency of lead with EDDS and EDTA was high in the pH range from 7 to 10 and the ability of lead removal with EDDS in this pH region is comparable to that with EDTA. Meanwhile, the removal efficiency of lead with citric acid was approximately 50% at pH 4 and decreased with increasing pH. Therefore, citric acid was hardly useful. Acid contribution was predominant for the removal of lead with EDDS and citric acid at pH 4 and the complexation between these chelating agents and lead were negligible. In the electrokinetic tests at ambient temparature, EDTA was more effective than EDDS and citric acid for lead transport through the soil by electrokinetic processing.

We propose a small-footprint X-cut thin-sheet lithium niobate optical modulator with high-speed and low-driving-voltage characteristics. Since an optical waveguide is folded by a mirror placed at one edge of the modulation chip, the chip can be shortened by about half. In addition, a wide modulation bandwidth can be achieved, because the path-length difference between the optical waveguide and the coplanar-waveguide (CPW) electrode is decreased to as short as possible by placing the CPW electrode as far as possible along the optical waveguide in the folded portion, and the microwave effective index is set to realize effective velocity matching between the lightwave and the microwave. A small footprint of 1.78 times 29 mm, a low half-wave voltage of 2.0 V at dc, and a 3-dBe modulation bandwidth of 20 GHz were obtained.

Pseudomonas sp. strain 7-6, isolated from active sludge obtained from a wastewater facility, utilized a quaternary ammonium surfactant, n -dodecyltrimethylammonium chloride (DTAC), as its sole carbon, nitrogen, and energy source. When initially grown in the presence of 10 mM DTAC medium, the isolate was unable to degrade DTAC. The strain was cultivated in gradually increasing concentrations of the surfactant until continuous exposure led to high tolerance and biodegradation of the compound. Based on the identification of five metabolites by gas chromatography-mass spectrometry analysis, two possible pathways for DTAC metabolism were proposed. In pathway 1, DTAC is converted to lauric acid via n -dodecanal with the release of trimethylamine; in pathway 2, DTAC is converted to lauric acid via n -dodecyldimethylamine and then n -dodecanal with the release of dimethylamine. Among the identified metabolites, the strain precultivated on DTAC medium could utilize n -dodecanal and lauric acid as sole carbon sources and trimethylamine and dimethylamine as sole nitrogen sources, but it could not efficiently utilize n -dodecyldimethylamine. These results indicated pathway 1 is the main pathway for the degradation of DTAC.

Lactobacillus casei TISTR 1500 was isolated from soil of a dairy wastewater treatment plant and selected as the most active azo dye degrader of 19 isolates. Growing cells and freely suspended cells of this strain completely degraded methyl orange, thereby decolorizing the medium. The strain stoichiometrically converted methyl orange to N,N-dimethyl-p-phenylenediamine and 4-aminobenzenesulfonic acid, which were identified by HPLC, GC, and GC-MS analyses. The enzyme activity responsible for the cleavage of the azo bond of methyl orange was localized to the cytoplasm of cells grown on modified MRS medium containing methyl orange. The effect of sugars, oligosaccharides, organic acids, metal ions, pHs, oxygen and temperatures on methyl orange decolorization by freely suspended cells was investigated. The optimal conditions for the decolorization of methyl orange by the Lactobacillus casei TISTR 1500 are incubation at 35 degrees C and pH 6 with sucrose provided as the energy source.

Eighteen bacterial stock cultures were examined for their ability to utilize NH(4)(+) and NO(3)(-) simultaneously in a medium containing NH(4)NO(3) with shaking using a test tube capped with a cotton stopper. Pseudomonas aeruginosa NBRC 12689 utilized 1 mg/ml of NH(4)NO(3) most rapidly of the cultures tested. The bacterium could completely utilize 5 mg/ml of NH(4)NO(3) within 3 d, 6 mg/ml of NH(4)Cl within 3 d, and 20 mg/ml of NaNO(3) within 2 d under optimum conditions. The addition of Fe(2+) to the NH(4)NO(3) medium markedly promoted the utilization of the two ions. When the Pseudomonas strain utilized 5 mg/ml of NH(4)NO(3) completely, the total nitrogen in the culture including its cells decreased to 41% of that of the NH(4)NO(3) originally provided. GC-MS analysis showed that the removed nitrogen was probably denitrified. When the bacterium was incubated in the NH(4)NO(3) medium with shaking in a vial sealed with a rubber stopper, N(2) accumulated, but not N(2)O at the final phase of cultivation. On the other hand, both N(2) and N(2)O were detected in the NaNO(3) medium. We concluded that the bacterium removed NH(4)(+) from NH(4)NO(3) as a nitrogen source for its cell components, together with the denitrification of NO(3)(-) under controlled shaking conditions. In addition, NH(4)(+) promoted the cell growth of the bacterium and denitrification to N(2), preventing the accumulation of N(2)O.

A bacterium, strain 10-L-2, that was isolated from soil and identified as Bacillus cereus grew well on medium containing 4-phenylenediamine and Polypepton. Strain 10-L-2 converted a wide variety of anilines, including 4-phenylenediamine, to their corresponding acetanilides. Growing cells acetylated a single amino group of 4-phenylenediamine to form 4-aminoacetanilide with a 97% molar yield, as shown by mass spectrometry and HPLC. Cell extracts exhibited arylamine N-acetyltransferase (NAT) activity toward 4-phenylenediamine. Two NATs, namely, NAT-a and NAT-b, were separated by DE52 column chromatography and were further purified and characterized. The subunit molecular masses of NAT-a and NAT-b were 31.0 and 27.5 kDa, respectively, as determined by SDS-PAGE analysis. The two enzymes had similar pH- and thermo-stabilities and were similarly affected by pH, temperature, and several reagents. The enzymes showed peak activity toward 5-aminosalicylic acid of the substrates tested, but they differed in substrate specificity. Only NAT-a had activity toward sulfamethazine. Although other wild-type bacterial cultures also synthesize NAT, the ability of strain 10-L-2 to convert and detoxify 4-phenylenediamine is much higher. This report provides the first evidence of two NATs in a eubacterium.

Enhanced solubilization of phenanthrene and pyrene from bentonite in micellar solution of Brij 30 and Triton X-100 has been studied. Experiments in batch bentonite/aqueous system were conducted to investigate the effectiveness of solubilization of phenanthrene and pyrene. The results obtained in this study are as follows: The solubilization of pyrene from bentonite in surfactant solutions was very low because of low water solubility and strong sorption onto bentonite of pyrene. Meanwhile, the solubilization of phenanthrene increased at bulk surfactant concentrations greater than the surfactant critical micelle concentration and was in order of Triton X-100>Brij 30. The solubilization of phenanthrene was also analyzed based on the partitioning of phenanthrene between bentonite, nonionic surfactant micelle and aqueous solution surrounding the micelles.

Perillae Herba, Sennae Folium, Cinnamomi Cortex, Phellodendri Cortex, Ginseng Radix, Glycyrrhizae Radix, Paeoniae Radix, and Zingiberis Rhizoma were irradiated with electron beam (5 MeV) and organic radicals were detected by ESR measurement, before and after irradiation (10 kGy) . A single line spectrum was detected at around g=2.005 in non-irradiated crude drugs, and radical concentrations were high in the leaf varieties of crude drugs. After irradiation, the signal intensity around g=2.005 increased, and a new subsignal was detected as a 3 mT shoulder of this signal. Broad, asymmetrically divided signals were also detected in irradiated root varieties of crude drugs. The free radical localized on the organic components of irradiated crude drugs tended to decrease with the water content. After irradiation, signal intensity reduced and reached a steady state after about 1 to 2 months. However, specificity of the ESR signal shape appearing after irradiation continued to be detectable for 6 months in leaf varieties and for a year in bark and root varieties of crude drugs. Consequently, it was concluded that ESR could be applied as an initial screening procedure to detect irradiated crude drugs.

Bordetella sp. strain 10d metabolizes 4-amino-3-hydroxybenzoic acid via 2-hydroxymuconic 6-semialdehyde. Cell extracts from 4-amino-3-hydroxybenzoate-grown cells showed high NAD(+)-dependent 2-hydroxymuconic 6-semialdehyde dehydrogenase, 4-oxalocrotonate tautomerase, 4-oxalocrotonate decarboxylase, and 2-oxopent-4-enoate hydratase activities, but no 2-hydroxymuconic 6-semialdehyde hydrolase activity. These enzymes involved in 4-amino-3-hydroxybenzoate metabolism were purified and characterized. When 2-hydroxymuconic 6-semialdehyde was used as substrate in a reaction mixture containing NAD(+) and cell extracts from 4-amino-3-hydroxybenzoate-grown cells, 4-oxalocrotonic acid, 2-oxopent-4-enoic acid, and 4-hydroxy-2-oxovaleric acid were identified as intermediates, and pyruvic acid was identified as the final product. A complete pathway for the metabolism of 4-amino-3-hydroxybenzoic acid in strain 10d is proposed. Strain 10d metabolized 2-hydroxymuconic 6-semialdehyde derived from 4-amino-3-hydroxybenzoic acid via a dehydrogenative route, not via a hydrolytic route. This proposed metabolic pathway differs considerably from the modified meta-cleavage pathway of 2-aminophenol and those previously reported for methyl- and chloro-derivatives.

We report herein the microphase separation structures (nanostructures) observed in Langmuir-Blodgett monolayers of an ABA block copolymer comprising of azobenzene-containing methacrylate and poly(ethylene oxide) as A and B block, respectively. After spreading this polymer on water in the trans and cis form of azobenzene, the monolayer is transferred onto mica at 1 mN m−1. The morphological features are observed by atomic force microscopy. The features of the nanostructures formed in the monolayers have obviously different features in the isomerization state of azobenzene. The conversions of the morphological features accompanied by the isomerization of azobenzene are attempted by light irradiation and dark adaptation. This paper focuses on the features in morphological conversions attained in the photo- and thermal processes.

A halotolerant strain FP-133, able to grow at concentrations of 0-12.5% (w/v) NaCl, was isolated from a fish paste and identified as Bacillus subtilis . B. subtilis strain FP-133 produced an intracellular protease which showed catalytic activity under saline conditions. The enzyme was purified to homogeneity 143-fold with a yield of 0.9%. The purified enzyme showed an optimum activity at a concentration of 5% (w/v) NaCl. After storage in 7.5% (w/v) NaCl at 4 degrees C for 24 h, the enzyme kept 100% of its activity. The molecular mass of the protease was determined to be 59 kDa by gel filtration; the protein consisted of four subunits each with a molecular mass of 14 kDa. The enzyme showed aminopeptidase activity. It acted on L-leucyl-p-nitroanilide, L-leucyl-beta-naphthylamide, and oligopeptides containing glycine, L-histidine, or L-leucine. The K(m ) and V (max) values for L-leucyl-p-nitroanilide were 18 microm and 2.2 mm/h mg, respectively. The enzyme was activated by Fe(2+), Fe(3+), and Ni(2+) in synergism with Mg(2+).

A bacterial isolate, strain PDa-1, grew well on basal medium supplemented with 2-phenylenediamine, sucrose, and ammonium nitrate and completely transformed 2-phenylenediamine. The isolate was identified as Bacillus cereus. The product formed from 2-phenylenediamine was identified by EI-MS and NMR as 2-aminoacetanilide; whole cells converted 2-phenylenediamine to the product with a 76% molar yield. Whole cells also showed a broad substrate specificity toward 20 of 26 tested arylamines with substituent groups of various size and positions. Especially 2-aminobenzoic acid, 4-aminosalicylic acid, 5-aminosalicylic acid, and 2-aminofluorene were converted completely to the corresponding product with an aminoacetyl group. Cell extracts of strain PDa-1 had a high arylamine N-acetyltransferase activity. The partially purified enzyme converted 2-phenylenediamine to 2-aminoacetanilide. Strain PDa-1 constitutively expressed the enzyme in the absence of 2-phenylenediamine. Effects of 2-phenylenediamine and 2-aminoacetanilide on growth indicated that this enzyme probably plays a role in the detoxification of toxic arylamines in this strain.

The authors propose a prechirped X-cut thin-sheet lithium niobate modulator. In this modulator, the /spl alpha/-chirp characteristic can be adjusted in the range of 0 to 0.8 by making coplanar waveguide electrodes asymmetric. In addition, a low-driving-voltage operation is achieved to make use of the thin-sheet structure without a SiO/sub 2/ buffer layer. We fabricated such a modulator with an /spl alpha/-chirp parameter of 0.65, a low half-wave voltage of 2.5 V, and a large bandwidth of 20 GHz. We also confirmed 10 Gb/s error-free transmission over an 80 km normal fiber (1.3 /spl mu/m zero-dispersion fiber) at a wavelength of 1.55 /spl mu/m by utilizing the modulator.

New rare-earth trifluorides of Gd1−xYbxF3 crystals were grown using the micro-pulling-down (μ-PD) method and single crystals were obtained for composition of x between 0.12 and 0.42 in the current study. Neither visible inclusions nor cracks were observed. Room temperature up-conversion luminescence spectra of Praseodymium (Pr3+) -doped Gd1−xYbxF3 were studied. Visible Pr3+ emission was obtained under infrared laser pumping on the ytterbium (Yb3+) absorption broadband at 935.5 nm. The origin of this emission will be discussed as a function of the decay times.

In electrokinetic soil remediation, contaminants are removed from soil and groundwater by action of an electrical potential applied across electrodes embedded in the contaminated medium. Soluble substances can be removed effectively by electroosmosis and ionic migration. However, contaminants that are adsorbed on the soil or are present as precipitates can not be effectively removed. In particular, the solubility of most heavy metals may be significantly reduced at elevated pH values. When impurities such as oxide and carbonate minerals are present, electrokinetics alone may not be effective in the extraction of heavy metals due to the higher acid / base buffer capacity. Also, acidification of the medium might cause large weight losses by dissolution of part of the solid matrix. It would, therefore, be better if the treatment were performed at neutral pH. In the present study, the effectiveness of introducing ethylenediaminetetraacetic acid (EDTA) as complexing agent to enhance the removal of cadmium from kaolinite by ion migration is examined. The investigation was carried out in a laboratory-scale column containing kaolinite contaminated with cadmium. As results of the study, cadmium migrated toward the anode without accumulation of cadmium and it was found that the effectiveness of EDTA for removing cadmium was significantly affected by the soil pH.

A Concurrent process for the synthesis and fabrication into rods of the machinable ceramic Ti3SiC2 by using a traveling-zone sintering method was investigated. Two different powder mixtures were prepared for the synthesis of Ti3SiC2. The first (TSC1) had the stoichiometric composition of Ti/Si/C = 3:1:2. In the second (TSC2), TiC was used instead of C to give a molar composition Ti/Si/TiC = 2:2:3. In the production of Ti3SiC2 rod from TSC1, there was a tendency for the cylindrical mold to become cracked during the sintering, because the synthesis of Ti3SiC2 from the simple mixture of Ti, Si and C occured by a tandem process and the primary exothermic reaction of Ti with C to form TiC caused a large thermal expansion of the material compact. On the other hand, Ti3SiC2 rod was successfully produced from the TSC2 mixture. Their density was elevated as increasing the sintering temperature and reducing the rate of movement of the stage, but employing too high temperature caused a reaction between the material powder and the mold, resulting in the product having unsatisfactory properties. The Ti3SiC2 rod produced contained varying amounts of TiC phase, the percentage of which showed a tendency to decrease under the same sintering conditions required to obtain a high density. We concluded that a well-densified, homogeneous Ti3SiC2 rod with high purity can be produced by the traveling-zone sintering method under the sintering conditions of a high temperature and a prolonged sintering time, if attention is paid to preventing reaction between the material compact and the mold.

Electrokinetic soil remediation by electroosmosis and ionic migration is restricted to soluble substances. At a higher pH, the soil particles sorb more heavy metals, such as cadmium, than at a lower pH and the precipitation reactions of heavy metals are promoted. Both mechanisms make heavy metals immobile, rendering cleanup more difficult and electrokinetic extraction inefficient. Therefore, the acidification of soils is very important to increase the cleanup efficiencies of heavy metals, such as cadmium by electrokinetic method from contaminated soils. Meanwhile, hexavalent chromium is more mobile and easily soluble. Hexavalent chromium has high solubility in water and exists as chromate, monochromate or dichromate anions depending on the pH of the solutions. This hexavalent chromium is the chemical form requiring remediation. In this study, cadmium and hexavalent chromium transport are predicted with a simple numerical method in which electrical flow is coupled with hydraulic flow, and the sorption process in the soils is induced in the model. The effects of some factors such as electrode configuration, electric field strength and electrode spacing for saturated soils are investigated using this numerical model. The results obtained this study are summarized as follows: The two-dimensional electrode configurations containing cathode surrounded by three or more anodes rapidly remove cadmium from soils compared with one-dimensional electrode configuration. Meanwhile, in the removal of hexavalent chromium from soils, the two-dimensional electrode configurations containing anode surrounded by three or more cathodes can be effectively utilized compared with one-dimensional electrode configuration. A larger electrode spacing increases the processing time required, and it was also found that a larger electric field strength reduced the processing time required.

Pr-doped KY 3 F 10 (Pr:KYF) single crystals were grown by the micro-pulling-down ( μ -PD) method. The crystals were transparent with a slightly greenish color, 2.5–3.0 mm in diameter and 35–45 mm in length. Neither visible inclusions nor cracks were observed. Photoluminescence spectra and decay kinetics of Pr:KYF were measured. Emission due to Pr 3+ 5d–4f transition, peaking around 260 nm and of the decay time of 24 ns was observed. The short decay time suggests such a Pr-doped material for a scintillator application. To our knowledge, this is the first report of the Pr 3+ 5d–4f luminescence transition accomplished in a fluoride host.

Betaine is an important osmoprotectant, synthesized by many plants in response to abiotic stresses. Almost all known biosynthetic pathways of betaine are two-step oxidations of choline. Recently, a biosynthetic pathway of betaine from glycine, catalyzed by two N -methyltransferase enzymes, was found. Here, the potential role of N -methyltransferase genes for betaine synthesis was examined in a freshwater cyanobacterium, Synechococcus sp. PCC 7942, and in Arabidopsis plants. It was found that the coexpression of N -methyltransferase genes in Synechococcus caused accumulation of a significant amount of betaine and conferred salt tolerance to a freshwater cyanobacterium sufficient for it to become capable of growth in seawater. Arabidopsis plants expressing N -methyltransferase genes also accumulated betaine to a high level in roots, stems, leaves, and flowers and improved seed yield under stress conditions. Betaine levels were higher than those produced by choline-oxidizing enzymes. These results demonstrate the usefulness of glycine N -methyltransferase genes for the improvement of abiotic stress tolerance in crop plants.

2-amino-5-carboxymuconic 6-semialdehyde is an unstable intermediate in the meta-cleavage pathway of 4-amino-3-hydroxybenzoic acid in Bordetella sp. strain 10d. In vitro, this compound is nonenzymatically converted to 2,5-pyridinedicarboxylic acid. Crude extracts of strain 10d grown on 4-amino-3-hydroxybenzoic acid converted 2-amino-5-carboxymuconic 6-semialdehyde formed from 4-amino-3-hydroxybenzoic acid by the first enzyme in the pathway, 4-amino-3-hydroxybenzoate 2,3-dioxygenase, to a yellow compound (epsilonmax = 375 nm). The enzyme in the crude extract carrying out the next step was purified to homogeneity. The yellow compound formed from 4-amino-3-hydroxybenzoic acid by this purified enzyme and purified 4-amino-3-hydroxybenzoate 2,3-dioxygenase in a coupled assay was identified as 2-hydroxymuconic 6-semialdehyde by GC-MS analysis. A mechanism for the formation of 2-hydroxymuconic 6-semialdehyde via enzymatic deamination and nonenzymatic decarboxylation is proposed based on results of spectrophotometric analyses. The purified enzyme, designated 2-amino-5-carboxymuconic 6-semialdehyde deaminase, is a new type of deaminase that differs from the 2-aminomuconate deaminases reported previously in that it primarily and specifically attacks 2-amino-5-carboxymuconic 6-semialdehyde. The deamination step in the proposed pathway differs from that in the pathways for 2-aminophenol and its derivatives.

Bordetella sp. 10d produces a novel dioxygenase catalyzing the meta-cleavage of 4-amino-3-hydroxybenzoic acid, 4-amino-3-hydroxybenzoate 2,3-dioxygenase (4A3HBA23D). A gene encoding 4A3HBA23D was cloned and named ahdA. The deduced amino acid sequence of ahdA showed 29.2-24.2% identities to those of prokaryotic and eukaryotic 3-hydoxybenzoate 3,4-dioxygenases in reported meta-cleavage dioxygenases. However, no identities were observed in the amino-terminal sequences of the first 29 amino acid residues. An ORF was found downstream of ahdA. The deduced amino acid sequence of the ORF showed identities to those of LysR family regulators involved in protocatechuate metabolism and contained motifs conserved in the regulators. On the basis of these results, the ORF was named ahdR encoding a putative LysR family regulator. The transcription start point of ahdA was localized 414-bp upstream of the start codon of ahdA. Two DNA-binding motifs of LysR family regulators were found upstream of the transcription start point. These observations suggest that a LysR family regulator encoded by ahdR regulates the expression of ahdA.

Burkholderia sp. strain AK-5 utilized 4-aminophenol as the sole carbon, nitrogen, and energy source. A pathway for the metabolism of 4-aminophenol in strain AK-5 was proposed based on the identification of three key metabolites by gas chromatography-mass spectrometry analysis. Strain AK-5 converted 4-aminophenol to 1,2,4-trihydroxybenzene via 1,4-benzenediol. 1,2,4-Trihydroxybenzene 1,2-dioxygenase cleaved the benzene ring of 1,2,4-trihydroxybenzene to form maleylacetic acid. The enzyme showed a high dioxygenase activity only for 1,2,4-trihydroxybenzene, with K m and V max values of 9.6 μM and 6.8 μmol min −1 mg of protein −1 , respectively.

We propose a newly designed X-cut lithium niobate (LiNbO/sub 3/) optical modulator. It has a two-step back-slot structure to satisfy the velocity-matching condition without the buffer layer of silicon dioxide (SiO/sub 2/). Accordingly, this modulator can achieve low drive voltage and low optical insertion loss. In addition, the dc-drift phenomena due to the buffer layer can be suppressed. This structure is fabricated with micromachining technology using excimer laser ablation. The optical 3-dB bandwidth of the fabricated modulator reaches 30 GHz, and the drive voltage is less than 3 V at 1 kHz. From the measurement of the optical eye diagram at 43.5-Gb/s, clear eye openings were obtained. This modulator is sufficient for 40-Gb/s optical transmission systems.

A bacterial strain that grew on 4-amino-3-hydroxybenzoic acid was isolated from farm soil. The isolate, strain 10d, was identified as a species of Bordetella. Cell extracts of Bordetella sp. strain 10d grown on 4-amino-3-hydroxybenzoic acid contained an enzyme that cleaved this substrate. The enzyme was purified to homogeneity with a 110-fold increase in specific activity. The purified enzyme was characterized as a meta-cleavage dioxygenase that catalyzed the ring fission between C2 and C3 of 4-amino-3-hydroxybenzoic acid, with the consumption of 1 mol of O2 per mol of substrate. The enzyme was therefore designated as 4-amino-3-hydroxybenzoate 2,3-dioxygenase. The molecular mass of the native enzyme was 40 kDa based on gel filtration; the enzyme is composed of two identical 21-kDa subunits according to SDS/PAGE. The enzyme showed a high dioxygenase activity only for 4-amino-3-hydroxybenzoic acid. The Km and Vmax values for this substrate were 35 micro m and 12 micro mol.min-1.(mg protein)-1, respectively. Of the 2-aminophenols tested, only 4-aminoresorcinol and 6-amino-m-cresol inhibited the enzyme. The enzyme reported here differs from previously reported extradiol dioxygenases, including 2-aminophenol 1,6-dioxygenase, in molecular mass, subunit structure and catalytic properties.

Electrokinetic soil remediation is an effective in-situ separation and removal technique used for extraction of heavy metals and some organic compounds from fine-grained soils. The technology uses electricity to affect chemical concentrations and water flow through the pores of soils. It is clear that electrokinetic soil remediation by electroosmosis and ionic migration is restricted to soluble substances. Contaminants that are adsorbed on the soil or are present as precipitates can not be effectively removed. In particular, the solubility of most heavy metals may be significantly reduced at elevated pH values. When impurities such as iron oxides are present, electrokinetics alone may not be effective in the extraction of heavy metals due to the higher acid/base buffer capacity. Also, acidification of the medium might cause large weight losses by dissolution of part of the solid matrix. It would therefore be better if the treatment were performed at neutral pH.In the present study, the effectiveness of introducing a complexing agent to enhance the removal of cadmium from kaolinite in the region of neutral pH by ionic migration is examined. The complexing agent selected was ethylenediaminetetraacetic acid (EDTA). The investigation was carried out in a laboratory-scale column containing kaolinite contaminated with cadmium. As the results of the study, cadmium migrates toward the anode without accumulation of cadmium and is successfully removed at the anode reservoir.

A bacterial strain F-5-2, isolated from soil and identified as Klebsiella pneumoniae, removed NH4+ completely in 24 h of aerobic cultivation in a medium containing 1 mg/ml of NH4NO3. However, 70% of the NO3- originally provided remained. When 100 microM Fe2+ was added to the medium, both NH4+ and NO3- were removed simultaneously and completely from the culture within 6 h of incubation. In addition, the amount of MoO4- in the medium markedly affected the bacterial cell growth and utilization of NH4+ and NO3-. The bacterium could remove 4 mg/ml of NH4NO3 completely in 48 h of aerobic cultivation in a medium containing 100 microM Fe2+ and 0.8 pM MoO4(2-). The total nitrogen in the culture containing its cells was decreased to 14% of that in the NH4NO3 originally provided. GC-MS analysis demonstrated that N2 was generated from the nitrogen atoms of both NH4+ and NO3-.