The machinability of leaded brass is well known to be affected by the microstructural properties of its matrix and microconstituents, particularly by the size and distribution of lead particles, and of course, by variation in machining conditions. The behavior of precipitation and coarsening of Pb particles during solidification and subsequent annealing of α- and β-single phase pure leaded brass was initially assessed by conventional metallographic methods. The size distribution was treated by a new statistical method. The results were later extended to α+β phase commercial leaded α+β brasses.
The size and distribution of Pb particles were quite different in the two types of brasses. In as-cast conditions, Pb particles in α-brass were much coarser and precipitated mainly on grain boundaries, while the distribution of Pb particles in β phase brass was relatively homogeneous and its size was much smaller.
The diffusion path and preferred nucleation sites of Pb atoms such as dislocations, sub-boundaries and grain boundaries were needed to the coarsening of Pb particles.
The solid solubility of Pb was likely to be larger in β-phase than in α-phase, and therefore, the distribution of Pb particles in β-phase was more homogeneous than in α-phase.
It was concluded that the size and distribution of Pb particles in commercial leaded brass are determined through the change in the grain structure of α and β phases.

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 本年度（平成30年度），健康科学大学健康科学部地域連携推進委員会が，「健康科学大学と富士河口湖町との包括連携協定（平成22年3月24日締結，以下包括連携協定）」に関連して行った活動を中心にまとめた。
 「包括連携協定」の目的の一つである「知的財産の共有」に関連して，本学教員が地域住民に対して「健康科学大学　公開講座（富士河口湖町・健康科学大学地域連携講座）」を開く一方，本学河口湖キャンパスに町役場の職員を特別講師として招き，本学学生を対象に地域行政の基本や富士河口湖町の取組みや課題について解説する「地域連携の理論と実際」を開催した。
 本学ボランティアセンターに登録している学生は，健康科学部・看護学部を合わせて，270名（平成30年10月1日現在）あり，富士河口湖町内外の地元団体の要請に応じて延べ364名がボランティア活動に参加した。また，ボランティア活動の一環として毎年恒例となっている富士河口湖町内の清掃活動「ウォーク・クリーニング隊」が5月27日（日）に行われ，40名の学生ボランティアが参加した。

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