Catalytic performance of a high-cell-density Ni honeycomb catalyst for methane steam reforming

The catalysis of methane steam reforming (MSR) by pure Ni honeycombs with high cell density of 2300 cells per square inch (cpsi) was investigated to develop efficient and inexpensive catalysts for hydrogen production. The Ni honeycomb catalyst was assembled using 30-μm-thick Ni foils, and showed much higher activity than that of a Ni honeycomb catalyst with cell density of 700 cpsi at a steam-to-carbon ratio of 1.36 and a gas hourly space velocity of 6400 h^?1 in a temperature range of 873–1173 K. Notably, the activity increased approximately proportional to the increasing geometric specific surface area of the honeycombs. The turnover rate of the Ni honeycomb catalyst was higher than that of supported Ni catalysts. The changes in chemical state of the Ni catalyst during hydrogen reduction and MSR reaction were analyzed by in situ X-ray absorption fine structure spectroscopy, which revealed that deactivation was mainly due to oxidation of the surface Ni atoms. These results demonstrated that the high-cell-density Ni honeycomb catalyst exhibits good performance for MSR reaction, and easy regeneration of the deactivated Ni honeycomb catalyst is possible only via hydrogen reduction.     

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。     

氘团簇离子(d3+)固体与相互作用过程中的团簇行为研究

讨论了由三个氘原子组成的氘团簇离子(d3+)束与独立氘离子束在轰击固体靶时,在原子过程和D-D核聚变过程中体现出的差别.对氘团簇与固体靶相互作用的机理进行了分析.     

Retrieving Domain-Specific Collocations by Co-occurrences and Word Order Constraints

In this paper, we describe a method for automatically retrieving collocations from large text corpora. This method comprises the following stages: (1) extracting strings of characters as units of collocations, and (2) extracting recurrent combinations of strings as collocations. Through this method, various types of domain-specific collocations can be retrieved simultaneously. This method is practical because it uses plain text with no specific-language-dependent information, such as lexical knowledge and parts of speech. Experimental results using English and Japanese text corpora show that the method is equally applicable to both languages.     

Antioxidative properties and flavonoid composition of Chenopodium quinoa seeds cultivated in Japan

To evaluate the nutritional advantages of quinoa seeds (Chenopodium quinoa Willd.) cultivated in Japan, antioxidative properties and flavonoid composition were determined and compared to corresponding data for conventionally-used cereals and pseudo-cereals, including quinoa seeds from South America. The antioxidant activities of these grains against DPPH radicals were strongly associated with the total phenolic content of the tested samples. The crude extracts of quinoa seeds cultivated in Japan exhibited higher antioxidative effects than those from South America and other cereals, excluding buckwheat. Four flavonol glycosides were isolated and identified from the Japanese quinoa seeds, and the chemical composition of the flavonoids – quercetin and kaempferol 3-O-(2″,6″-di-O-α-rhamnopyranosyl)-β-galactopyranosides (1 and 4), quercetin 3-O-(2″,6″-di-O-α-rhamnopyranosyl)-β-glucopyranoside (2), and quercetin 3-O-(2″-O-β-apiofuranosyl-6″-O-α-rhamnopyranosyl)-β-galactopyranoside (3) – was evaluated through quantitative determination. Trioside 2 was isolated for the first time from quinoa seeds. These glycosides were not detected in extracts from any of the tested grains except quinoa. The aglycone quercetin content of the Japanese quinoa seeds is higher than in the seeds from South America and buckwheat. The amounts of quercetin and kaempferol formed via acidic hydrolysis in quinoa are much higher than those of conventionally-used edible plants. The quinoa seeds cultivated in Japan are the most effective functional foodstuff – in terms of being a source of antioxidative and bioactive flavonoids – among cereals and pseudo-cereals.     

SEPARATION OF SAMARIUM ISOTOPES BY A CROWN ETHER

ABSTRACT

Samarium isotopes were fractionated in a liquid-liquid extraction system using dicychlohexano-18-crown-6. High precision isotope ratio measurements with a multicollector mass spectrometer made it possible to evaluate the contributions of the nuclear size and shape and the nuclear spin to the chemical isotope separation effect. The maximum value of the unit mass enrichment factor (?_u was observed to be 0.00161 ± 0.00002. The odd/even enrichment factor of ¹⁴⁷Sm was ?_O/E = ?0.00101 ± 0.00062 and that of ¹⁴⁹Sm was ?_O/E = ?0.00049 ± 0.00050. Enrichment factors were affected by nuclear mass, nuclear volume and nuclear spin in addition to vibrational motion of molecule. The nuclear volume effect was 1.94 times as large as the nuclear mass effect. The odd/even atomic mass effect was explained with 6s²-6s6p transition in optical isotope shift of Sm I. The correction due to the nuclear spin of ¹⁴⁷Sm was ?_spin; = ?0.0016 and that of ¹⁴⁹Sm was ?_spin; = ?0.0014.     

Tools with built-in thin film thermocouple sensors for monitoring cutting temperature

The ability to monitor in real time, the thermal activation and thermal impact to cutting tools has been very appealing to the manufacturing industries. Such responses can be measured with appropriate sensors such as thin film thermocouples (TFTs) built in cutting tools. The challenges have been to instrument the tool, equipment and sensors, which can withstand high stress and temperature in machining process. In this work, the sequence of fabricating the built-in TFTs and experimental setups are proposed and demonstrated. The cutting experiments are carried out under different cutting conditions for A6061-T6 aluminum alloy and finally cutting temperature is measured at very high cutting speeds up to 16 m/s.