• Title/Summary/Keyword: 기원물질

Search Result 407, Processing Time 0.037 seconds

Radiocarbon for Studies of Organic Matter Cycling in the Ocean (방사성탄소를 이용한 해양 유기탄소 순환 연구 동향)

  • Hwang, Jeomshik
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.17 no.3
    • /
    • pp.189-201
    • /
    • 2012
  • Radiocarbon is a powerful tool for studies of carbon cycling in the ocean. Development of measurement technology of accelerator mass spectrometry has enabled researchers to measure radiocarbon even in specific compounds. In this paper, a brief introduction on radiocarbon measurement and reporting of radiocarbon data is provided. Researches that used radiocarbon measurements on bulk organic matter, organic compound classes, and specific organic compounds are reviewed. Examples include works to understand the cycling of particulate and dissolved organic matter, biochemical composition of particulate organic matter, post-depositional transport of sedimentary organic matter, selective incorporation of fresh organic matter by benthic organisms, chemoautotrophy by archaea, and sources of halogenated chemical compounds found in marine mammals.

Nanosized Calcite in the Chinese Loess (중국 뢰스의 나노 방해석)

  • Jeong, Gi-Young
    • Journal of the Mineralogical Society of Korea
    • /
    • v.20 no.4
    • /
    • pp.255-260
    • /
    • 2007
  • The loess on the Chinese loess plateau is not only the accumulation of Asian dust but also the source materials of Hwangsa. The eolian carbonates of the loess were dissolved and reprecipitated to form secondary pedogenic carbonates by the post-depositional weathering during the interglacial time. Mineralogical analysis shows that the secondary calcites are composed mostly of a nanosized fibrous calcite with rather constant width ($30{\sim}50nm$) and highly variable length. The nano calcite is the major authigenic mineral, which occurs as the fine-grained matrix of the loess and paleosol. The nano calcite was recently reported in the Hwangsa, where it was originated from the source regions of Chinese loess plateau.

Origin of the Jechon granite: a review of the Sr isotope data (제천 화강암의 기원: 스트론티움 동위원소 자료의 재고)

  • 권성택;진명식;주승환
    • The Journal of the Petrological Society of Korea
    • /
    • v.1 no.2
    • /
    • pp.132-137
    • /
    • 1992
  • Review of metamorphic terms and rock names from various published articles in Korea reveals that they have often been misused and they may lead to a faulty results in the interpretations of the geologic mass. Their usage can be classified into several groups. A few simple rules are proposed for use in naming metamorphic rocks. The new rock names make by the proposed rules are listed as table with old names.

  • PDF

Tracing Source and Concentration of Riverine Organic Carbon Transporting from Tamjin River to Gangjin Bay, Korea (탐진강-강진만의 댐하류 열린하구 시스템에서 유기탄소의 조성 및 기원 변화 연구)

  • Park, Hyung-Geun;Kang, Dong-Won;Shin, Kyung-Hoon;Ock, Giyoung
    • Korean Journal of Ecology and Environment
    • /
    • v.50 no.4
    • /
    • pp.422-431
    • /
    • 2017
  • The biogeochemical information of riverine organic matter gives a detailed and integrated recording of natural and anthropogenic activity within a watershed. To investigate the changes in quality and quantity of organic carbon transporting from mountain to ocean via river channels, we estimated the concentrations of dissolved (DOC) and particulate organic carbon (POC), and then traced the source origin of POC using stable carbon isotopes ratio before and after summer rainfalls in the Tamjin River and Ganjin Bay, Korea. Along the small watershed, a total of 13 sites including headwaters, dam reservoir, river and estuary were established for the study. We found some interesting findings in the aspect of distribution of DOC/POC concentration changing their origin sources dynamically flowing downstream. In particular, the river channel transport downstream mainly DOC to river mouth, although upper dam reservoir increased POC concentration by phytoplankton production in summer. Whereas, in the river mouth and estuary, POC was dominated not only by local supply from nearby reed saltmarsh, but also by marine phytoplankton production, respectively. The findings can contribute to increasing the understanding of riverine organic carbon transport in upper large dam and lower open estuary system.

Emission Rates of Biogenic Volatile Organic Compounds (BVOCs) from Various Tree Species in Korea (I) (국내 수종별 BVOCs 방출량 (1))

  • Chang, Hanna;Son, Jounga;Je, Sun Mi;Oh, Chang-Young;Cho, Minseok;Kim, Juwan;Kim, Jaehyeon;Choi, Won-Sil;Lee, Young-Kyu
    • Journal of Korean Society of Forest Science
    • /
    • v.110 no.4
    • /
    • pp.543-553
    • /
    • 2021
  • This research focused on the investigation of isoprene and terpene emissions from 30 major urban tree species. We conducted sampling using a specific dynamic enclosure system between August and September 2020. Seedlings less than three years old were enclosed in a chamber consisting of a 400 L transparent Tedlar bag. The air-flows from the chamber's outlet were sampled using Tenax-filled sorbent tubes in the presence of standard conditions (temperature: 30℃, PAR: 1,000 μmol/m2/sec). A thermal desorption GC/MS system was used to analyze 38 BVOC compounds (isoprene, monoterpene, sesquiterpene, oxygenated monoterpene, and sesquiterpene). Isoprene emitters included Phyllostachys bambusoides, Quercus serrata, Daphniphyllum macropodum, and Buxus Koreana. Monoterpene emitters included Pinus rigida, Acer pictum subsp. mono, Larix kaempfer, Magnolia denudata, Metasequoia glyptostroboides, Pinus koraiensis, Pinus densiflora, and Abies holophylla. The monoterpene emission profiles were dominated by α-pinene, myrcene, limonene, β-pinen, and sabinene, while caryophyllene and farnesene were the prominent sesquiterpenes. Predominant oxygenated monoterpene compounds were also discovered as pulegone, borneol, menthol, eucalyptol, and nerol, while caryophyllene oxide were the prominent oxygenated sesquiterpenes. Sesquiterpenes and oxygenated sesquiterpenes had relatively lower contributions for all species.

고양이의 마디신경절에서 VIP 양성세포의 의의

  • 김영모;조정일;한창준
    • Proceedings of the KSLP Conference
    • /
    • 1996.11a
    • /
    • pp.94-94
    • /
    • 1996
  • 미주신경의 마디신경절내에 존재하는 신경세포는 경부, 흉강 및 복강의 감각신경을 지배하는 것으로 알려져 있으며 이와 관련된 SP, CGRP 등의 신경펩디드의 분포에 관하여 많은 보고가 이루어졌다. Vasoactive Intestinal Peptide(VIP)는 혈관, 평활근, 분비선 주위에 분포하는 부교감신경세포의 전달물질로서 후두의 자율신경계의 조절에 중요한 역할을 하고 있다 이러한 VIP지배신경의 기원에 관해서는 미주신경이나 후두신경, 그리고 일부 후두 구조내에 존재하는 부신경절(Paraganglia)에서 기원한 후 신경절 부교감신경으로 알려져 있는데, 즉 미주신경의 마디신경절은 단지 감각신경의 기원이 되는 신경세포 집합체로 마디신경절과 자율신경계의 상관관계에 대한 연구는 극히 드문 실정이다. 그러나 일부 보고에서 성문하부의 점막상피에서 SP나 CGRP외에도 VIP 양성세포가 발견됨으로써 일반적으로 자율신경계 세포로 알려진 VIP 양성세포의 기원과 기능은 더 규명되어야 할 부분의 하나로 사료된다 금번 저자는 고양이의 마디신경절에 대하여 면역 조직화학적 방법을 통한 VIP양성 세포의 출현여부를 관찰함으로써 마디신경절과 자율신경계와의 상관관계를 알아보고자 하였다.

  • PDF