This study aims to examine the risk of electrical fire in places where electric heat wires are used. In general, the use of electric heating wires is becoming more common and prevalent in a bid to prevent increasing damage caused by freezing and bursting in residential water pipes, factory pipes and irrigation pipes in vinyl greenhouse and a variety of heat wire products are available in market with legal safety requirements imposed on them. However, the widespread use of anti-freezing burst heat wire products has caused increasing incidents of fire, which often fail to be incorporated into statistics due to quick onsite extinguishing and insignificant damage although damage is gradually on the rise. Against this backdrop, this study aims to look into the possibility of ignition caused by electric heat wires and the mechanism of how it turns into catching fire through overheat and short circuit tests for anti-freezing burst electrical heat wires (hereinafter called the ‘heat wire’) and expects to serve as the basis for further observations and analyses on the cause of fire and the process of ignition in a scientific manner.

The phytochemicals of many plants suggest their potential use as dietary supplements in cancer chemoprevention and chemotherapy. In the present study, antitumor activity of Cudrania tricuspidata, a plant native to East Asia, was investigated. Cell growth inhibition of the extract on HT-29 colorectal adenocarcinoma using MTT colorimetric assay was determined. Apoptosis on HT-29 cells was performed by DNA fragmentation analysis. PGE2 release was measured by enzyme immunoassay, because PGE2 is a key protumorigenic prostanoid in many human cancers. For the ROS scavenging activity, ROS level was detected by laser scanning confocal microscope. It was found that methanol extract of leaves inhibits cell viability by inducing apoptosis as evidenced by DNA fragmentation. Stem bark decreases synthesis of PGE2, inflammatory mediator. Fruits exhibited pronounced ROS scavenging activity. Taken together, these results suggest that Cudrania tricuspidata exerts growth inhibition and anti-oxidation on HT-29 cells through apoptosis, ROS scavenging respectively that it may have anti-cancer properties.

액체금속로 전열관재료용 개량 9Cr-1Mo강의 특성에 미치는 텅스텐의 영향을 고찰하기 위하여 개량 9Cr-1Mo강에 텅스텐을 2wt.% 첨가하여 템퍼링 온도에 따른 기계적 특성 및 미세조직의 변화를 조사하였다. 미세조직을 관찰한 결과 템퍼링시 전위회복에 의해 형성되는 셀 구조가 나타나는 템퍼링 온도는 개량 9Cr-1Mo강의 경우 700˚C인 반면, 텅스텐을 첨가한 9Cr-0.5Mo-2W강의 경우는 750˚C이었으며, 이 결과로부터 텅스텐 첨가는 전위회복을 지연하였음을 알 수 있다. 텅스텐을 첨가하여도 템퍼링 온도에 따라 생성되는 석출물의 종류는 차이가 없었으나, 텅스텐을 첨가한 강에 있는 석출물에는 텅스텐이 포함되어 있었다. 텅스텐의 첨가로 경도값, 고온 인장강도 그리고 항복강도가 증가하였다. 이것은 텅스텐 첨가로 인한 미세구조의 안정화에 기인하는 것으로 보인다. 충격시험에서는 항복강도가 낮은 개량 9Cr-1Mo강이 더 우수한 충격파괴특성을 가졌다.