Photosensitive poly(vinylene carbonate)s based on reaction development patterning with dilute aqueous alkaline solution

We examined positive‐tone pattern formation based on reaction development patterning (RDP) using hydrolysis of carbonate groups on the side chains of vinyl polymers. Homopolymers and copolymers with carbonate groups were prepared by radical polymerization using vinylene carbonate (VCA) as a monomer. Application of RDP to the VCA homopolymer resulted in unclear positive‐tone pattern because the high reactivity of the carbonate group led to insufficient difference in solubility between the exposed and unexposed areas. When we applied RDP using 5.0 wt% NaOH_aq as developer to the copolymers between VCA and vinyl acetate (P(VCA–VAc)s), clear positive‐tone patterns were successfully obtained. The effect of the ratio of carbonate groups in the copolymers on the development property of the RDP process was examined, and the use of a copolymer in which the ratio between VCA and VAc was 1:0.6 was found to yield positive‐tone pattern with the highest contrast. Pattern formation using more dilute developer (1.0 wt% NaOH_aq) was also achieved. Though conventional photosensitive polymers are required to have acidic or protected acidic groups for alkaline development, we succeeded in addition of photosensitivity to P(VCA–VAc)s, which do not have such functional groups, by using dilute aqueous alkaline solutions as developers. © 2015 Society of Chemical Industry     

从《世阿弥传书》到《匠明》:能乐观演空间尺度体系的传承与演变

本文以日本传统能乐艺术的集大成者、能乐师世阿弥的传书为研究对象，从他在室町时代(1338—1573) 前期对能乐观演空间的言论中分析、总结出世阿弥对能乐观演空间设计尺寸的原理性认识。其后，将世阿弥的设计尺寸理论与江户初期成书的建筑技术书《匠明》中对能乐观演空间的设计尺寸的规定进行比较，考察两者之间的变化。最终，总结了江户时代(17 世纪初)对室町时代能乐观演空间尺寸体系的继承以及演变。     

Autonomous calibration method of the reference flat surface of an interferometer without using a standard flat surface

An autonomous method for calibrating the reference flat surface of an interferometer is proposed with the uncertainty analysis. The method consists of three phases; the first step is multiple rotating shifts of a specimen, the second is a linear shift, and the last is multiple rotating shifts again. The profile of the reference flat surface is basically determined by the linear shift. The linear shift errors that occurred during the linear shift are identified by the rotating shifts. The rotating shift errors caused by the rotating shifts can be compensated and the residual uncertainty can be reduced in proportion to the square root of the number of rotating shifts per one revolution. Finally, the uncertainty analysis is carried out in detail.     

Layer-by-layer assembly through weak interactions and their biomedical applications

The surface design and control of substrates with nanometer- or micrometer-sized polymer films are of considerable interest for both fundamental and applied studies in the biomedical field because of the required surface properties. The layer-by-layer (LbL) technique was discovered in 1991 by Decher and co-workers for the fabrication of polymer multilayers constructed mainly through electrostatic interaction. The scope and applicability of this LbL assembly has been extended by introducing molecularly regular conformations of polymers or proteins by employing, for the first time, weak interactions such as van der Waals interactions and biological recognition. Since these weak interactions are the sum of the attractive or repulsive forces between parts of the same molecule, they allow macromolecules to be easily arranged into the most stable conformation in a LbL film. By applying this characteristic feature, the template polymerization of stereoregular polymers, stereoregular control of surface biological properties, drastic morphological control of biodegradable nano materials, and the development of three-dimensional cellular multilayers as a tissue model were successfully achieved. It is expected that LbL assembly using weak interactions will promote further interest into fundamental and applied studies on the design of surface chemistry in the biomedical field.     

Novel Highly Acidic Nanoporous Cage Type Materials and Their Catalysis

Acylation of aromatic compounds such as veratrole (1,2-dimethoxybenzene), anisole, isobutyl benzene, and 2-methoxynaphthalene with acetic anhydride (Ac₂O) has been investigated over different solid acid catalysts such as MWW, BEA, FAU, MOR, and MFI. MWW catalysts have been characterized by X-ray diffraction, N₂ adsorption–desorption isotherm, and HR-FESEM characterization techniques. The reaction is studied in the temperature range 313–353 K under N₂ atmosphere. Among the catalysts tested, MWW was found to be more active than other zeolites. This is mainly due to its three dimensional porous structure with excellent textural characteristics. The effect of veratrole/Ac₂O molar ratio, catalyst concentration, and reaction temperature has been optimized to get higher conversion of Ac₂O. Under the optimized reaction conditions, MWW gave the Ac₂O conversion of 64.3% with a selectivity to acetoveratrone (3′,4′-dimethoxyacetophenone) (100%). It was also found that the structural features and acidity play an important role in the conversion and product distribution in the acylation of different aromatic substrates like anisole, isobutyl benzene, and 2-methoxy naphthalene. MWW catalyst has been reused in few cycles after regeneration by washing with ethyl acetate followed by calcination at 500 °C for 4 h without loss in its activity. The reaction kinetics of the catalyst was also studied and the results are discussed in detail.     

Effect of coprecipitated barium ferrite on the cure characteristics and dynamic properties of natural rubber–ferrite composites around percolation

The influence of coprecipitated hexagonal barium ferrite BaFe₁₂O₁₉ phase on the cure characteristics and dynamic properties of natural rubber–ferrite composites has been studied as a function of ferrite loading up to 220 phr (part per hundred part of rubber). Unusual characteristics of coprecipitated ferrite particles were discovered by scanning electron microscope. The results show that scorch time t₁₀ and cure time t₉₀ decrease dramatically with increasing ferrite content up to critical ferrite loading. After 160 phr, t₉₀ increases sharply with increasing ferrite content, in contrast to saturation of t₁₀. Minimum torque recorded normal behavior at low ferrite loading, whereas it decreases with increasing ferrite content at high ferrite loading because of dilution effects. The storage modulus E′ and loss modulus E″ decrease with increasing temperature. The loss tangents (tanδ) of the composites are greater than those of the pure rubber. Linear viscoelastic behavior was observed as a result of the homogeneity and compatibility of the composites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Monitoring groundwater variation by satellite and implications for in-situ gravity measurements

In order to establish a new technique for monitoring groundwater variations in urban areas, the applicability of precise in-situ gravity measurements and extremely high precision satellite gravity data via GRACE (Gravity Recovery and Climate Experiment) was tested. Using the GRACE data, regional scale water mass variations in four major river basins of the Indochina Peninsula were estimated. The estimated variations were compared with Soil-Vegetation-Atmosphere Transfer Scheme (SVATS) models with a river flow model of 1) globally uniform river velocity, 2) river velocity tuned by each river basin, 3) globally uniform river velocity considering groundwater storage, and 4) river velocity tuned by each river basin considering groundwater storage. Model 3) attained the best fit to the GRACE data, and the model 4) yielded almost the same values. This implies that the groundwater plays an important role in estimating the variation of total terrestrial storage. It also indicates that tuning river velocity, which is based on the in-situ measurements, needs further investigations in combination with the GRACE data. The relationships among GRACE data, SVATS models, and in-situ measurements were also discussed briefly.     

Transcriptional Induction of Metallothionein by Tris(pentafluorophenyl)stibane in Cultured Bovine Aortic Endothelial Cells

Vascular endothelial cells cover the luminal surface of blood vessels and contribute to the prevention of vascular disorders such as atherosclerosis. Metallothionein (MT) is a low molecular weight, cysteine-rich, metal-binding, inducible protein, which protects cells from the toxicity of heavy metals and active oxygen species. Endothelial MT is not induced by inorganic zinc. Adequate tools are required to investigate the mechanisms underlying endothelial MT induction. In the present study, we found that an organoantimony compound, tris(pentafluorophenyl)stibane, induces gene expression of MT-1A and MT-2A, which are subisoforms of MT in bovine aortic endothelial cells. The data reveal that MT-1A is induced by activation of both the MTF-1–MRE and Nrf2–ARE pathways, whereas MT-2A expression requires only activation of the MTF-1–MRE pathway. The present data suggest that the original role of MT-1 is to protect cells from heavy metal toxicity and oxidative stress in the biological defense system, while that of MT-2 is to regulate intracellular zinc metabolism.