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Global water security is jeopardized by the presence of anthropogenic contaminants, which can persist resiliently in the environment and adversely affect human health. Surface adsorption of polluting species is an effective technique for water purification. In this work, redox-active magnetic compounds were designed for the targeted removal of inorganic and organic anions in water via polymeric redox-active vinylferrocene (VFc) and pyrrole (Py) moieties. An Fe

Oblique angle deposition can reduce ion bombardment and facilitate precursor migration on surfaces, which can affect the crystallographic properties of thin films. We prepared nanostructured Bi2Te3 thin films by oblique deposition at room temperature, and analyzed their structural and thermoelectric properties. The thin films were deposited by radio-frequency magnetron sputtering on a glass substrate, which was tilted at angles of 0–80° to the target. Cross-sectional SEM images showed that the samples consisted of columnar nanostructures, with the voids between the columnar grains increasing as the oblique angle was increased owing to the shadowing effect. XRD analysis indicated that crystallite size increased as the oblique angle was increased, although highly oriented thin films were not obtained. The highest mobility and electrical conductivity were observed at an oblique angle of 20° due to the relatively large crystallite size of the thin film obtained at this angle, as well as the small number of voids between the columnar grains. As a result, this film exhibited the highest power factor (3.1 μW/(cm·K2)), approximately six times higher than that obtained by normal sputtering deposition. Therefore, we conclude that using a moderate oblique angle can improve the thermoelectric properties of thin films.

The carrier concentration and mobility in nanocrystalline Bi2Te3 thin films with controlled strain were investigated through a combination of infrared spectroscopy and first-principles calculations, and the results were compared to Hall measurement data. The thin films were deposited on flexible polyimide substrates using radio frequency magnetron sputtering at a substrate temperature of 200 °C. Various compressive strains were introduced into the thin films by changing the curvature of the flexible substrate prior to deposition. The magnitude of the strain was determined by X-ray diffraction, which found that the strain in the c-axis direction was more greatly influenced by the magnitude of curvature than that in the a,b-axis direction. The average crystallite size remained at ∼30 nm across the entire range of strains tested, but did slightly increase with decreasing strain. The electronic transport properties were estimated by infrared spectroscopy using the Drude model, with the effective mass being determined from the band structure using first-principles calculations based on density functional theory. This combined analysis exhibited a similar decrease in carrier concentration and increase in mobility with decreasing strain as the Hall measurements, though the difference between the results of the two measurement methods became greater as the strain decreased.

The effect of crystal grain size on the thermoelectric properties of nanocrystalline antimony telluride (Sb

A new chiral phosphine ligand (R)-1 possessing a fluoroalcohol moiety was prepared. The (R)-1-coordinated Rh(I) complex showed an excellent catalytic activity for asymmetric 1,2-addition of arylboronic acids to aldehydes to afford highly enantioenriched diarylmethanols. The fluoroalcohol moiety in ligand (R)-1 plays a pivotal role for the high enantioselectivity of the present Rh(I)-catalyzed transformation.

The effects of crystal orientation and grain size on the thermoelectric properties of Bi2Te3 thin films were investigated by conducting experimental and theoretical analyses. To vary the crystal orientation and grain size, we performed oblique deposition, followed by thermal annealing treatment. The crystal orientation decreased as the oblique angle was increased, while the grain size was not changed significantly. The thermoelectric properties were measured at room temperature. A theoretical analysis was performed using a first principles method based on density functional theory. Then the semi-classical Boltzmann transport equation was used in the relaxation time approximation, with the effect of grain size included. Furthermore, the effect of crystal orientation was included in the calculation based on a simple semi-experimental model. A maximum power factor of 11.6 µW/(cmK2) was obtained at an oblique angle of 40°. The calculated thermoelectric properties were in very good agreement with the experimentally measured values.

The effect of crystal grain size on the thermoelectric properties of nanocrystalline antimony telluride (Sb2Te3) thin films was investigated by experiments and first-principles studies using a developed relaxation time approximation. The Sb2Te3 thin films were deposited on glass substrates using radio-frequency magnetron sputtering. To change the crystal grain size of the Sb2Te3 thin films, thermal annealing was performed at different temperatures. The crystal grain size, lattice parameter, and crystal orientation of the thin films were estimated using XRD patterns. The carrier concentration and in-plane thermoelectric properties of the thin films were measured at room temperature. A theoretical analysis was performed using a first-principles study based on density functional theory. The electronic band structures of Sb2Te3 were calculated using different lattice parameters, and the thermoelectric properties were predicted based on the semi-classical Boltzmann transport equation in the relaxation time approximation. In particular, we introduced the effect of carrier scattering at the grain boundaries into the relaxation time approximation by estimating the group velocities from the electronic band structures. Finally, the experimentally measured thermoelectric properties were compared with those obtained by calculation. As a result, the calculated thermoelectric properties were found to be in good agreement with the experimental results. Therefore, we can conclude that introducing the effect of carrier scattering at the grain boundaries into the relaxation time approximation contributes to enhance the accuracy of a first-principles calculation relating to nanocrystalline materials.

Oxygen-containing heterocyclic systems are important structures in organic chemistry because of their presence in many biologically active compounds. In this work, a Lewis acid-catalyzed cyclization of ethenetricarboxylate derivatives 1 with substituted propargyl alcohols to give methylenetetrahydrofurans was investigated. Reaction of 1 and gamma-silicon-substituted propargyl alcohols 4 with ZnBr2 at 80-110 degrees C led to (Z)-silicon-substituted products stereoselectively. Reaction of 1 and gamma-ester-substituted propargyl alcohol 7 in the presence of various Lewis acids gave ester-substituted methylenetetrahydrofurans stereoselectively. Interesting Lewis acid dependency on stereoselectivity for the reaction of 7 was found. Reaction of alpha-substituted propargyl alcohols also gave cyclized products.

A new zinc- and indium-promoted conjugate addition-cyclization reaction to afford nitrogen- and oxygen-containing five-membered heterocycles has been developed. Reaction of ethenetricarboxylates with propargylamines (1 equiv) in the presence of ZnBr2 or InBr3 afforded methylenepyrrolidines in high yields. The stoichiometric use of ZnBr2 or InBr3 at room temperature and the catalytic use of InBr3-Et3N at 80 degrees C were effective. Reaction of ethenetricarboxylates with propargyl alcohol in the presence of ZnBr2 or InBr3 afforded methylenetetrahydrofurans.

A novel cyclization reaction of ethenetricarboxylate derivative aromatic compounds in the presence of various Lewis acids gave benzo-annulated cyclic compounds such as oxindole and benzofuran derivatives via Friedel-Crafts intramolecular Michael addition in high yields. For example, the reaction of diethyl 2-[(N-methyl-N-phenylcarbamoyl)methylene]malonate (1a) in the presence of ZnCl2 at room temperature gave diethyl 2-(1-methyl-2-oxoindolin-3-yl)malonate (2a) in 98% yield. The reactions also proceeded with a catalytic amount of a Lewis acid such as AlCl3, ZnCl2, ZnBr2, Sc(OTf)3, or InBr3.

Treatment of sulfinylaziridines, which were synthesized from 1-chloroalkyl p-tolyl sulfoxides and imines, with ethylmagnesium bromide gave nonstabilized aziridinylmagnesiums by a sulfoxide-magnesium exchange reaction. The cross-coupling of the aziridinylmagnesiums with various kinds of alkylhalides was realized in high yields by using Cu(I) iodide as a catalyst, and the reaction was found to be stereospecific. The coupling products were hydrogenated with Pd(OH)2 in alcohol to give the amines bearing a quaternary chiral center in quantitative yields. Synthesis of both enantiomers of the amines bearing a quaternary chiral center was realized starting from optically active (R)-chloromethyl p-tolyl sulfoxide in good overall yields with perfect asymmetric induction.

A high-yield alkylation of aziridinylmagnesiums, which were generated from sulfinylaziridines with EtMgBr by sulfoxide–magnesium exchange, with primary alkyl halides in the presence of Cu(I) iodide as a catalyst, was realized. The alkylated aziridines were converted in quantitative yield to amines bearing a quaternary chiral center by hydrogenation with Pd(OH) 2 . A synthesis of the optically active amines, bearing a quaternary chiral center, was realized, starting from optically active ( R )-chloromethyl p -tolyl sulfoxide, in good overall yield by the presented method.

Background Pulmonary arteriovenous malformations (PAVMs) are rarely encountered in clinical practice. The prevalence of PAVMs associated with hereditary hemorrhagic telangiectasia (HHT) has been estimated based on the rate in the family members of HHT patients, but the prevalence of PAVMs in the general population remains unknown. Methods We retrospectively examined the prevalence and clinical characteristics of PAVMs as detected by a low-dose thoracic CT screening program for lung cancer at the Hitachi Medical Center and the Hitachi General Health Care Center in the northern part of Ibaraki Prefecture, Japan. Results From 2001 to 2007, we identified eight patients (seven females and one male) with PAVMs among 21,235 initial screening participants (the mean age of the patients with PAVMs and that of the screening participants was 60.6 years). The prevalence of PAVMs was estimated at 38 per 100,000 individuals [95% confidence interval (CI)=18-76]. The diameter of the PAVMs was a mean of 6.6 mm, and none of the lesions could be detected by chest X-ray. Females older than 60 years tended to have larger PAVMs than younger women did (p=0.06). Two patients (25%) were diagnosed with HHT. One patient had previously undergone surgery for a brain abscess. Conclusion PAVMs are more prevalent than previously reported, especially among females.

Autodiploid strains were induced by colchicine treatment of Aspergillus niger WU-2223L, a citric acid-producing strain. In shaking culture, a representative autodiploid strain, L-d1, yielded higher citric acid than the parental strain, WU-2223L. When glucose was used as a carbon source, L-d1 and WU-2223L produced 67.2 g/l and 62.0 g/l of citric acid, respectively, from 120 g/l of glucose in 9 d-cultivation. Furthermore, the autodiploid strain L-d1 produced 49.6 g/l of citric acid, 1.4 times as much as that produced by WU-2223L from 120 g/l of soluble starch. During the whole period of cultivation with starch, the extracellular glucoamylase activity of L-d1 was on the same level as that of WU-2223L, but the extracellular acid-protease activity of L-d1 was much higher. The addition of pepstatin, an inhibitor of acid protease, to the culture broth at 2 d greatly increased the extracellular glucoamylase activity, and citric acid production by L-d1 reached a level of 59.0 g/l. During several subcultivations on both minimal and complete agar media, the autodiploid strains were genetically stable since they formed diploid conidia in their uniform colonies without producing sectors, and maintained citric acid productivity. However, when cultivated on minimal and complete agar media containing benomyl as a haploidizing reagent, the autodiploid strains readily formed sectors of haploid segregants. The properties of the haploid strains obtained by the benomyl treatment of the autodiploid strains were similar in morphology and citric acid productivity to those of the parental strain, WU-2223L. These results indicated that the enhanced production of citric acid from soluble starch by the autodiploid strains was due to autodiploid formation but not to gene mutation caused by the colchicine treatment.

Three novel linear plasmids, pDHL1 (8.4 kb), pDHL2 (9.2 kb) and pDHL3 (15.0 kb), were discovered in the halophilic (salt-tolerant) yeast Debaryomyces hansenii. Exonuclease treatment indicated that all three plasmids were blocked at their 5' ends, presumably, by analogy with most other eukaryotic linear plasmids which involved protein attachment. The Debaryomyces plasmids were entirely cured simply by growing cells in normal culture medium, but were stably maintained in culture medium containing salts, sorbitol or glycerol at suitable concentrations. This suggested that the pDHL plasmids required an osmotic pressure for stable replication and maintenance. The Debaryomyces yeast secreted a killer toxin against various yeasts species. Toxin activity was demonstrated only in the presence of salts such as NaCl or KCl, but this killer phenotype was not associated with the pDHL plasmids. Analysis of the plasmid-curing pattern suggested that pDHL3 may play a key role in the replication of the Debaryomyces plasmids. Southern hybridization showed that an extensive homology exists between specific regions of pDHL1 and pDHL2, whereas pDHL3 is unique.

BNF is found to be highly effective for the addition of arylboronic acids to aromatic aldehydes and is thus of interest in the preparation of bioactive diaryl methanols.

A high-yield alkylation of aziridinylmagnesiums, which were generated from sulfinylaziridines with EtMgBr by sulfoxide–magnesium exchange, with primary alkyl halides in the presence of Cu(I) iodide as a catalyst, was realized. The alkylated aziridines were converted in quantitative yield to amines bearing a quaternary chiral center by hydrogenation with Pd(OH) 2 . A synthesis of the optically active amines, bearing a quaternary chiral center, was realized, starting from optically active ( R )-chloromethyl p -tolyl sulfoxide, in good overall yield by the presented method.

Zinc Lewis acid-catalyzed cyclization of ethenetricarboxylate derivatives 1 with 2-ethynylanilines has been examined. Reaction of 1,1-diethyl 2-tert-butyl ethenetricarboxylate 1b with 2-(trimethylsilylethynyl)aniline substrates in the presence of Zn(OTf)2 gave bridged quinoline derivatives in 43−85% yield. The reaction of 1b with 2′-aminoacetophenone also gave the bridged quinoline derivative in 41% yield. Thermal reaction of bridged quinolines (180−190 °C) afforded indole derivatives in moderate to good yields.

Zinc Lewis acid-catalyzed cyclization of ethenetricarboxylate derivatives 1 with 2-ethynylanilines has been examined. Reaction of 1,1-diethyl 2-tert-butyl ethenetricarboxylate 1b with 2-(trimethylsilylethynyl)aniline substrates in the presence of Zn(OTf)(2) gave bridged quinoline derivatives in 43-85% yield. The reaction of 1b with 2'-aminoacetophenone also gave the bridged quinoline derivative in 41% yield. Thermal reaction of bridged quinolines (180-190 degrees C) afforded indole derivatives in moderate to good yields.

肺癌の皮膚転移の2例を報告した。症例1は59歳男子で胸部の腫瘤。組織は扁平上皮癌。症例2は71歳女子で背部の皮下硬結。組織は大細胞癌。いずれも単発性であつた。本邦の転移性皮膚癌の集計報告をまとめると, 頻度の高い原発臓器は乳房, 胃, 肺の順であるが, 最近は肺癌が増えている。また, 本邦の肺癌皮膚転移の報告例について考察を加えた。

Oxygen-containing heterocyclic systems are important structures in organic chemistry because of their presence in many biologically active compounds. In this work, a Lewis acid-catalyzed cyclization of ethenetricarboxylate derivatives 1 with substituted propargyl alcohols to give methylenetetrahydrofurans was investigated. Reaction of 1 and γ-silicon-substituted propargyl alcohols 4 with ZnBr2 at 80−110 °C led to (Z)-silicon-substituted products stereoselectively. Reaction of 1 and γ-ester-substituted propargyl alcohol 7 in the presence of various Lewis acids gave ester-substituted methylenetetrahydrofurans stereoselectively. Interesting Lewis acid dependency on stereoselectivity for the reaction of 7 was found. Reaction of α-substituted propargyl alcohols also gave cyclized products.

Lewis acid-catalyzed cyclization of various 2-(N-arylcarbamoyl)-methylenemalonates to give nitrogen-containing benzo-annelated heterocycles was investigated in terms of selectivity. Reaction of substrates with various alkyl groups on nitrogen proceeded to give oxindole derivatives. Cyclization reaction of diester-amides of MeO and halogen-substituted anilines in the presence of catalytic Lewis acid (ZnCl 2 , SnCl 4 , AlCl 3 , Zn(OTf) 2 , Sc(OTf) 3 , etc.) gave oxindoles in high yields. Interesting regioselectivity was observed for metahalogen substrates. Dimethoxyisoquinoline analogs were also obtained by this reaction using a catalytic Lewis acid.

A novel cyclization reaction of ethenetricarboxylate derivative aromatic compounds in the presence of various Lewis acids gave benzo-annulated cyclic compounds such as oxindole and benzofuran derivatives via Friedel–Crafts intramolecular Michael addition in high yields. For example, the reaction of diethyl 2-[(N-methyl-N-phenylcarbamoyl)methylene]malonate (1a) in the presence of ZnCl2 at room temperature gave diethyl 2-(1-methyl-2-oxoindolin-3-yl)malonate (2a) in 98% yield. The reactions also proceeded with a catalytic amount of a Lewis acid such as AlCl3, ZnCl2, ZnBr2, Sc(OTf)3, or InBr3.

Orientador : Mauro Augusto Demarzo Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil Mestrado

The cellular localization of the constitutive β-glucosidase in the mycelia of Trichoderma viride was investigated by cell fractionation using disrupted mycelia and mycelial protoplasts. In 2-d-old mycelia, approximately 86% of the cellular enzyme activity was detected in the fraction containing cytosol, plasma membrane, and periplasm, and 14% in that containing cell wall. With incubation of the mycelia in a lytic enzyme solution, the β-glucosidase was released rapidly before protoplast formation was observed. After 4 h of incubation in the lytic enzyme solution, only 4% of β-glucosidase activity was detected in the protoplasts recovered. These results indicated that most of the constitutive β-glucosidase was on the cell surface, especially in the cell wall and periplasm.

Lithium-ion cells with 5-Ah capacity were fabricated using a spinel Li 1.1 (Ni 0.025 Ti 0.025 Mg 0.02 )Mn 1.83 O 4 as a cathode active material, graphitized carbon as an anode active material, and 1 M LiPF 6 /ethylene carbonate + diethyl carbonate + dimethyl carbonate as an electrolyte. In order to improve the calendar life of the cell, we investigated the degradation mechanism by measuring the thickness of the solid electrolyte interphase (SEI) on anode active material. The SEI thickness was measured by focused ion beam, scanning electron microscope, and X-ray photoelectron spectroscopy. The thickness of the SEI was initially 0.04 μm, and after storage for 392 days at 25 and 40°C, the thickness was 0.15 and 0.45 μm, respectively. The capacity decreased with increase in the thickness of SEI, because Li in the cell is consumed by forming SEI. The amount of Li consumption was estimated theoretically assuming that SEI is formed by a reaction between intercalated Li and the electrolyte in SEI on the negative carbon surface, and a diffusion of the electrolyte in the SEI is the rate-determining step of the reaction. The theoretical equation showed a good agreement with experimental capacity fade at 25, 40, and 60°C for the storing days up to 380 days. A voltage decrease of the cell after 1-s at 20 A of discharge current was measured to estimate roughly the increase of the cell internal resistance during storage. The increase of SEI resistance was estimated by the theoretical equation and compared with the experimental voltage drop data after 1-s discharge. However, the theoretical data was not in a good agreement with the experimental data. The reason is that the charge-transfer resistance on the anode also increases during storage. Another reason is the resistance change of the cathode during the storage.