Nitrogen and oxygen isotope ratios (δ15N, δ18O) of nitrate have been measured by denitrifier method aiming to analyze N material flows and their sources (ocean, lake, river, and groundwater). The denitrifier method developed in 1990s allows us to measure both δ15N and δ18O of nitrate simultaneously employing small amounts (i.e. 30nmol). The instruments including online auto-injection of N2O gas are still expensive(generally cost more than two hundred thousand US$). Here, we have developed a self-made auto-injection system of N2O to IRMS connected to the interface(Conflo III). This self-made system is inexpensive(i.e. twenty thousand US$) and has equal precisions of δ15N and δ18O with the past systems.
Elementary particle physics is a discipline that aims to understand the origin of matter at the most fundamental level. An outline of elementary particle physics is presented as plainly as possible in the three-part tutorial. In the first part, the most fundamental particles called quarks and leptons are introduced. Quarks consist protons, neutrons and mesons, which Dr. Hideki Yukawa had predicted, while neutrinos and electrons are called leptons along with muons, which were discovered by Dr. Yoshio Nishina.
How to emit X-rays easily using a cigarette lighter (electric discharge) is explained, and a history of studies of X-ray production methods using electrification or charge up is also included. Comments are given for the related patents. The related following topics are explained:X-ray emission from pyroelectric crystal, a series use of pyroelectric crystals, and peel-off of adhesive tape. Relations to PIXE(particle-induced X-ray emission) experiment and nuclear fusion using pyroelectric crystal are also given. Explanations of palm-top size EPMA(electron probe X-ray microanalyzer) and XRF(X-ray fluorescence) spectrometers that can be made in laboratory quite easily are added. Application of pyroelectric XRF to the following materials are given:leather, cinnabar seal ink, polyvinyl chloride, cup, steel, paint. The detection limit of pyroelectric XRF is down to 180 ppm and, if pretreated, 0.1 ppm. The general trend of X-ray instruments is miniaturization and XRF using even a few wattage X-ray tube is superior to SPring-8 synchrotron XRF in some experimental conditions. Special attention is noted to the danger of an electric circuit, where a high voltage is applied, because of the exposure to X-rays, produced by the electrification under specific conditions of electrification and a vacuum level.