The Characteristics of Trace Metal Distribution of Artificial and Natural-Origin Suspended Particulate Matter (SPM) by grain size

Air pollution caused by suspended particulate matter (SPM) has increased remarkedly in industrial areas, and this has become an emergency issue in the global environment. Atomospheric SPM influences the local ecosystem including various plants and animals. It is necessary to examine the distribution characteristics of such trace metals in fine particulates (especially those with a diameter (φ) of less than 2.1μm). The Environment Agency of the Japanese goverment will complete analysis of the a concentration of suspended particulate matter less than 2.4μm by the end of 1999, and will be examining the relationship between the concentration of suspended particulate matter (0.1-9.0μm) with consideration given to the particle size throughout two years. It became clear that the metals of artificial origin such as Pb, V, Cd, Ni, Cr, existed in fine particulates (0.1 or more 2.0μm). By contrast, the metals of natural origin, such as Ti, Mn, Mg, Sr, mainly existed in coarse Area in Japan.浮遊粒子状物質（0.1～9.0μm）中の酸溶解性金属について、各金属の粒径別濃度分布を検討した。ことに人為起減金属と考えられるPb、Cd、Ni,Crは微小粒子（0～2.0μｍ）部分に存在する事が判明した。これに対し天然起源の金属であるTi、Mn、Mg、Sr等は粗大粒子（2.1～9.0μｍ）に多く存在した。すなわち微小部分に存在する人に由来の金属は酸性雨などによる溶解性が大きいと考えられる。そのために人に由来の金属は動植物のみならず人体への影響も引き起こし易い状況にあることが推察された。また本調査地点の倉敷市は立地的には水島工業地帯の北東に位置していること、西風、南西風が卓越した地点であることから、工業地帯の煙突からの放出物質ならびに自動車排気ガス等の汚染の影響を受けやすいことが判明した。発生源同定、発生源対策等の観点からも、今後において浮遊粒子状物質を含むエアロゾルの粒径別の化学組成の研究、特に微小粒子領域における詳細な研究が望まれる。現在の日本の大気汚染防止法は直径100分の1mm以下の浮遊粒子状物質について基準を設けているが、もっと小さい2.5μｍに焦点を当てた基準等の検討も必要であろう。浮遊粒子状物質には、ほこりやちり等の天然由来のものに含まれるのに対して、2.5μｍ以下は排ガス等の人為的な発生源が中心であり、肺の組織の深部まで到達して沈着しやすく健康への影響も大きいことからも、今後より詳細な研究と汚染防止対策が切望される

Synthesis and Fluorescence of 2-pyrone Derivatives for Electroluminescence Devices(SPECIAL ISSUE CELEBRATING TEN YEARS OF ESTABLISHMENT OF FACULTY OF ENVIRONMENTAL STUDIES)

A convenient method of synthesizing 6-aryl- and 6-styryl-4-methylsulfanyl-2-oxo-2H-pyran derivatives through the reactions of various active methylene compounds with ketene dithioacetals and investigation of the fluorescence of the products in the solid state are described. The structure-activity relationships of various 2-pyrone derivatives and the effects of different aryl and styryl substituents on the aryl group were clarified. Materials which are strongly fluorescent in the primary colors (red, green, and blue) are the most important materials in the field of organic electroluminescence (EL). The 2-pyrone derivatives synthesized in this work emitted light at 447～620 nm in the solid state