自励振動式蒸気エンジンの提案及びその高性能化に関する研究

学位の種別: 論文博士審査委員会委員 : (主査)東京大学教授 鹿園 直毅, 東京大学教授 加藤 千幸, 東京大学特任教授 橋本 彰, 東京大学准教授 姫野 武洋, 東京大学講師 長谷川 洋介University of Tokyo(東京大学

Status of butyltins contamination in sediments from Kong Kong Laut, Johor after five years of global banning

This study is aimed to determine the concentration of butyltin and the physic-chemical factors in marine sediment after five years of total global banning. Level of butyltins namely tributyltins (TBT), dibutyltin (DBT) monobutyltin (MBT) and the physicochemical parameters of sediments (sediment texture, pH and total organic carbon (TOC)) were measured in sample collected from nine stations at Kong Kong Laut. Concentrations of tributyltin were varied from undetected to 945.7 μg kg-1 dry weight, undetected to 188 μg kg-1 dry weight for DBT, and undetected to 55.2 μg kg-1 dry weights for MBT. The highest levels of TBT and DBT were found at station number 1, which is in the vicinity of dock yard. Level of pH and type of sediment are almost uniform in all nine stations except for TOC. No significant relationships were found between physicochemical parameters and the three butyltins. These findings suggest that TBT in station number 1 was freshly introduced and that the main source was suspected from maintenance work conducted in the dockyard

スミヲモチイタスイシツジョウカ

Although water important source of life and energy, millions of people worldwide are suffering from a shortage of fresh and clean drinking water. Industrialization, population expansion and urbanization have largely contibuted to the severe water pollution. Namely, the main sources of water pollution can be attributed to the discharge of untreated toxic industrial and municipal waste, the dumping of industrial effluent and runoff from agricultural fields. In order to reuse the little available water, many water treatment systems have been developed. Among the various water treatment technologies, the adsorption process is considered as a better method, because of convenience, lower cost, ease of operation and simplicity of design. In particular, charcoal is re-examined as an adsorbent. In this paper, the characteristics of charcoal, mechanism of adsorbing and application of activated carbon, wood charcoal and bamboo charcoal are reviewed

Small molecule-based detection of non-canonical RNA G-quadruplex structures that modulate protein translation

Tandem repeats of guanine-rich sequences in RNA often form thermodynamically stable four-stranded RNA structures. Such RNA G-quadruplexes have long been considered to be linked to essential biological processes, yet their physiological significance in cells remains unclear. Here, we report a approach that permits the detection of RNA G-quadruplex structures that modulate protein translation in mammalian cells. The approach combines antibody arrays and RGB-1, a small molecule that selectively stabilizes RNA G-quadruplex structures. Analysis of the protein and mRNA products of 84 cancer-related human genes identified Nectin-4 and CapG as G-quadruplex-controlled genes whose mRNAs harbor non-canonical G-quadruplex structures on their 5′UTR region. Further investigations revealed that the RNA G-quadruplex of CapG exhibits a structural polymorphism, suggesting a possible mechanism that ensures the translation repression in a KCl concentration range of 25–100 mM. The approach described in the present study sets the stage for further discoveries of RNA G-quadruplexes

タケスミニヨルユウキリンカゴウブツルイ、フタルサンエステルルイオヨビタカンホウコウゾクタンカスイソルイノジョキョ

竹炭を用いて、有機リン化合物類10種類、フタル酸エステル類8種および多環芳香族炭化水素類8種の吸着性について検討した。竹炭1ｇに対して、トリフェニルフォスフェイト（TPP）は約3㎎、トリス（2-クロロエチル）フォスフェイト（TCEP）は約1.5㎎、クロロピリフォスは約2.5㎎であったが、その他の有機リン化合物類は4-5㎎吸着した。フタル酸エステル類については、ジエチルフタレート (DEP)、ジ－ｎ－ヘキシルフタレート (DHP) および　ジシクロヘキシルフタレート(DCHP)は2.5-3.5㎎であったが、その他の化合物は4-5㎎が吸着した。多環芳香族炭化水素類については、ベンゾ[a]フェナンスレン(B[a]PH)、3,4-ベンズピレン(B[a]P)およびペリレン（PARY)は2.5-3.5㎎であったが、その他は約4㎎と高かった。次に平衡濃度と吸着量の関係をみた。有機リン化合物類は、平衡濃度が高くなるにつれ、吸着量が減少する傾向がみられた。フタル酸エステル類については、DEPとジプロピルフタレート(DPrP)は、平衡濃度が高くなると吸着量が増加したが、それ以外の物質は有機リン化合物類と同様減少した。多環芳香族炭化水素類は、平衡濃度が高くなるにつて、吸着量が増加する傾向が認められた。0.002㎎/Ｌ の有機リン化合物類を含む試験水500mlに竹炭を10ｇ加え24間撹拌後の除去率を算出すると、有機リン化合物類は95-100%、フタル酸エステル類はジ-n-ブチルフタレート(DBP)とDCHPを除き98-100%であった。多環芳香族炭化水素類は86-100%であった。このように、水中に存在する有機リン化合物類、フタル酸エステル類および多環芳香族炭化水素類のほとんどを、竹炭を用いて除去することができた。Water is the essence of life, however, millions of people are suffering from a shortage of drinking water. Industrialization, population expansion and urbanization have largely contributed to severe water pollution due to the discharge of untreated toxic industrial and municipal wastes, the dumping of industrial effluent and runoff from agricultural fields. In order to reuse the limited amount of available water, many water treatment systems have been developed. The applications of bamboo charcoal as a water treatment material for organophosphoric compounds (OPs), phthalic acid esters (PAEs) and polyaromatic hydrocarbons (PAHs) were investigated and the relationships between the equilibrium concentrations of their chemical compounds and the absorbed amounts by bamboo charcoal were discussed. Although the equilibrium concentrations of OPs and most PAEs increased as the absorbed amount decreased, the equilibrium concentrations of PAHs decreased. Removal rates of OPs ranged between 95％and 100％. Removal rates of PAEs except for Di-n-buty1 phthalate (DBP) and Dicyclohexy1 phthalate (DCP) were in the range of 98-100%. Removal rates of PAHs were in the range of 86-100%. It was found that bamboo charcoal is an important item for the removal of harmful chemical compounds in water samples