Earozoru Kenkyu
Online ISSN : 1881-543X
Print ISSN : 0912-2834
ISSN-L : 0912-2834
Volume 19 , Issue 4
Winter
Showing 1-9 articles out of 9 articles from the selected issue
Feature Articles -Dry Deposition of Atmospheric Aerosols-
Technical paper
  • Hidenori YOSHIYAMA
    2004 Volume 19 Issue 4 Pages 274-280
    Published: December 20, 2004
    Released: April 18, 2007
    JOURNALS FREE ACCESS
    The polytetrafluoroethylene (PTFE) filter has been recommended for the measurement of mass concentration of ambient fine particles smaller than 2.5 μm (PM2.5) . Since the PTFE filter tends to be negatively charged, the electrical charge would introduce serious error in the evaluation of PM2.5 concentration with electric microbalances. The present work investigated the influence of filter charge on the determination of filter mass as well as a method which minimizes the error due to the electrical charge, using the PTFE filter of 140 mg weight with a support ring.
    It was found that that attractive electrostatic force exerting between filter and microbalance greatly influences the measured mass of filter and that the use of neutralizer can reduce the error, effectively. The use of filter measurement kit, which shields the electrical field from the filter, was also effective for reducing the error in the mass measurement of filter.
    Download PDF (658K)
Series article
  • Yasuo MORIMOTO
    2004 Volume 19 Issue 4 Pages 281
    Published: December 20, 2004
    Released: April 18, 2007
    JOURNALS FREE ACCESS
    Download PDF (491K)
  • Hisamitsu OMORI, Yasuo MORIMOTO
    2004 Volume 19 Issue 4 Pages 282-286
    Published: December 20, 2004
    Released: April 18, 2007
    JOURNALS FREE ACCESS
    Chronic obstructive pulmonary disease (COPD) is currently one of the major causes of death in the world. Further increases in the prevalence and mortality rates for the disease are predicted in the coming decades in Japan. The major causes of this increase are past smoking behavior and the aging of the population. COPD is a disease state characterized by airflow limitation. Airflow limitation is associated with an abnormal inflammatory response of the lungs to noxious particles or gases. Smoking is the single greatest independent risk factor for the development of COPD. In this article, we review the pathogenesis, pathology and pathophysiology of COPD. We also review the effects of cigarette smoking and smoking cessation on age-related pulmonary function decline, and prevalence of emphysema detected by thoracic CT screening.
    Download PDF (758K)
feedback
Top