• Title/Summary/Keyword: Secondary Source

Search Result 700, Processing Time 0.024 seconds

The Responses of a Small Lake Watershed to an Inorganic Carbon Cycle (무기탄소 순환에 대한 소규모 호수 유역의 반응)

  • Cho, Youngil
    • Journal of Korean Society on Water Environment
    • /
    • v.29 no.5
    • /
    • pp.610-617
    • /
    • 2013
  • Investigating the budgets of alkalinity and dissolved inorganic carbon (DIC) in lake water systems is significant for the examination of the behavior of a lake as a sink or a source with respect to the circulation of inorganic carbon chemistry. Budgets of total alkalinity ($Alk_T$) and DIC in Onondaga Lake, which was polluted by chronic calcium (Ca) loading in spite of the closure of soda ash ($Na_2CO_3$) facility, were determined by the analyses of inorganic carbon chemistry in tributary stream channels linked to the lake. AlkT and DIC fluxes of Onondaga Creek and Ninemile Creek occupied 65% and 54%, respectively, as larger tributary streams in comparison with other tributaries as well as different input sources. Budget calculations indicate that 18% of AlkT and 11% of DIC inputs to Onondaga Lake, respectively, remained immobilized in the Lake. This suggests that Ca chronically leached had been precipitated with inorganic carbon or remineralized by secondary mineral formation during the experimental period. In this study, the assumed mass balance calculation in Onondaga Lake with tributary streams resulted in exhibiting that the lake played a role of the sink for the inorganic carbon cycle.

$H_{2}$ production of photosynthetic bacteria transferred TOL plasmid from flavobacterium odoratum (Flavobacterium odoratum의 TOL 플라스미드를 전달받은 광합성세균으로부터의 수소 생성)

  • 오순옥;조인성;이희경;민경희
    • Korean Journal of Microbiology
    • /
    • v.29 no.6
    • /
    • pp.408-415
    • /
    • 1991
  • TOL plsmid size of Flavobacterium odoratum SUB53 was estimated as 83 Md and the optimum concentration of m-toluate degradation by TOL plasmid was 5 mM. $H_{2}$ production by Rhodopseudomonas sphaeroides KCTC1425 was largely dependent on nitrogenase activity and showed the highest at 30 mM malate with 7 mM glutamate as nitrogen source. Nitrogenase activities were inhibited by 0.3 mM $NH_{4}^{+}$ions, to be appeared the decrease of $H_{2}$ production. Conjugation of TOL plasmids from F. odoratum SUB53 and Pseudomonas putida mt-2 to R. sphaeroides showed the optimum at the exponential stage of recipient cells in presence of helper plasmid pRK2013. According to the investigation of catechol-1,2-oxygenase (C-1, 2-O) and catechol-2,3-oxygenase (C-2,3-O) activities of R. sphaeroides C1 (TOL SUB53) and C2 (TOL mt-2), the gene for C-2,3-O is located on TOL plasmid and gene for C-1, 2-O on the chromosome of R. sphaeroides. m-Toluate was biodegraded by TOL plasmid in R. sphaeroides C1 and C2, presumably to be produced $H_{2}$ gas from the secondary metabolites of m-toluate.e.

  • PDF

Environmental Impact Assessment of Uranium Anormaly in Stream System around the Shinbo Talc Mine (신보활석광산 주변에 형성된 우라늄 이상치가 지표수계 환경에 미치는 영향)

  • 나춘기;정재일
    • Economic and Environmental Geology
    • /
    • v.33 no.4
    • /
    • pp.261-271
    • /
    • 2000
  • In order to evaluate the environmental impact of U anormaly in the drainage system around the Shinbo talc mine area, U contents, their distribution patterns, bioaccumulation and a-radioactivity in stream water, stream sediments and aquatic organisms were investigated. The U contents of stream water attenuated with increasing distance from the mine area. The same attenuation pattern is shown in stream sediments from mine to 0.75 km downstream, although these contain highly enriched U contents (24~83 mg/kg) comparing with the international average concentration of surface soils (0.79~11 mg/kg). However, U content increases abruptly in sediment at 1.5 km downstream, probably due to detrital migration and rediposition of U enriched sediments. Futhermore, enriched U in downstream sediments occur in high proportions of carbonate and Fe-Mn oxide bounded forms, which show high potential of a secondary pollution source. For aquatic organisms, bio accumulation degree of U are in the order: aquatic larvae>black snail>mountain frog>crawfish. Cultured trout by the U enrich groundwater (387 ${\mu}g$/l) shows U accumulation in the part of branchia (CRs 5.25) and bones (CRs 11.2) but not in flesh (CRs 0.03). Total a-radioactivity have been measured in the level as 0.47 nCi/l for groundwater, 2.94~18 nCi/kg${\cdot}$DW for organisms and 93~328 nCi/kg${\cdot}$DW for sediments.

  • PDF

Fracture characterization with high frequency single-hole EM survey

  • Seo, Soon-Jee;Song, Yoon-Ho;Kim, Hee-Joon;Lee, Ki-Ha;Suh, Jung-Hee
    • Proceedings of the KSEEG Conference
    • /
    • 1999.04a
    • /
    • pp.90-93
    • /
    • 1999
  • We present a high frequency electromagnetic (EM) inversion scheme for detecting and characterizing a fracture using single-hole data. At high frequencies, say above tens of mega-hertz, since displacement currents cannot be ignored, electrical permittivity as well as electrical conductivity is to be considered together for analyzing the EM scattering data. In this paper, we have developed a three-step inversion scheme to map the fracture and to evaluate its electrical conductivity and permittivity. We performed EM profiling along the z-axis using three-component receivers for each source. The model was excited by a vertical magnetic dipole and the resistant magnetic fields were inverted using the non-linear least-squares method. Background resistivity and permittivity were easily obtained using vertical magnetic fields below 1 MHz and above 10 MHz, respectively. Both the vertical and dipping sheets were successfully mapped using the phase difference between 40 and 41 MHz. The electrical property of the sheet was well resolved using the information obtained in the previous two steps and secondary magnetic fields. Our study shows the potential of imaging the fracture in single-hole survey environment using the high frequency EM method.

  • PDF

Research on the Characteristics of Water inside a Human's Body and its Metabolism (인체내 수액의 특성 및 대사기전에 대한 연구 -진액.혈.한.소변.정의 생성기전 및 성질에 대하여-)

  • 백상용
    • The Journal of Korean Medicine
    • /
    • v.24 no.3
    • /
    • pp.130-137
    • /
    • 2003
  • Water, in a living being, is as essential as the essence derived from food is in maintaining one's life. The concepts are expressed in forms of "food and drink" and "drink-food" in the ${\mathbb{\ulcorner}}Hwangjenakyoung{\mathbb{\lrcorner}}$ and most of the other oriental medicine related references. Following the steps of the human body's metabolism, the water source builds up characteristic formations, such as bodily fluids (blood/perspiration/urine/essence), in each transforming phase according to the nature of the Ki that propels the transformation. Furthermore, each characteristic formations has its' own suitable duties, distinctive features and its field of activation. The vital energy of life is identified as a positive property due its fluidity and its formless nature. In order for this vital energy to come into its own, it needs to weld into one with the material-natured body of the negative property which will embrace the positive property and transform it into body fluid. Water taken into a body will undergo the first activation of Ki, dissolving the Wigi and the Wongi and transforming into the primary body fluid. The delicates among the dissolved Ki will once again go through a transformation in the Jungcho. It will turn into red blood, with influence of the vital function. When the vital energy completes its duties in all parts of the body, it combines with water again and transforms into the secondary bodily fluid. This is when the Takgi gets filtered and the new enriched essence is created.

  • PDF

A Study of the Producing Conventions of Lifestyle News in the Newspaper (신문매체에서의 라이프스타일 뉴스 제작관행 연구)

  • Hong, Eun-Hee
    • Journal of the Korean Home Economics Association
    • /
    • v.45 no.2
    • /
    • pp.105-117
    • /
    • 2007
  • The purpose of this study is to examine the producing conventions of lifestyle news and search for problems with these conventions. This research is about the entire process of production of lifestyle news, while dividing it into sourcing conventions and editing conventions. With this concept as a goal, we analyzed the content of lifestyle articles over the last six months in two types of daily papers, and then interviewed journalists in-depth. The results of the study indicate that as for sourcing conventions, reporting is accomplished by focusing on a reporter and using anonymous or false-named news sources. These conventions spread widely over not only ideas but also valuation of news items and security of news sources. This is because in terms of lifestyle news that is closely related to one's private life such as family relations, a reporter often attempts to prevent a news source from being exposed to secondary damage, such as the criticism of readers. In the meantime, editing conventions of lifestyle articles are irrelevant in terms of the quality of each media enterprise. Instead, these conventions are connected with the day of publication. Moreover, editors tend to approach editing conventions to spread the culture of upper classes, recognizing that the readers are consumers who have purchasing power.

Development a simple MEMS-based astronomical adaptive optics system at laboratory

  • Yu, Hyung-Jun;Park, Yong-Sun;Chae, Jong-Chul;Yang, Hee-Su
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.36 no.2
    • /
    • pp.132.2-132.2
    • /
    • 2011
  • We are developing Adaptive Optics (AO) system for astronomical use. The He-Ne laser works as an artificial light source. The tip-tilt correction servo is added to our AO system. The tip-tilt term, among the Zernike terms, is the biggest contributor of wavefront deformation caused by atmospheric turbulence at small telescopes. The tip-tilt correction servo consists of a Piezo tip-tilt platform with a mirror, a quadrant photodiode as a tip-tilt sensor, and controllers. The Shack-Hartmann wavefront sensor measures the residual wavefront errors and they are corrected by the MEMS (Micro Electro Mechanical System) deformable mirror. The MEMS deformable mirror allows the compact size at low cost compare to adaptive secondary mirror and other deformable mirrors. As the frame rates of the MEMS deformable mirror is about tens of kHz, the frame rates of the detector in wavefront sensor is the bottleneck of the wavefront correction speed. For faster performance, we replaced a CCD which provides frame rates only 70 Hz with a CMOS with frame rates up to 450 Hz.

  • PDF

High Boost Converter Using Voltage Multiplier (배압회로를 이용한 고승압 컨버터)

  • Baek Ju-Won;Kim Jong-Hyun;Ryoo Myung-Hyo;Yoo Dong-Wook;Kim Jong-Soo
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.55 no.8
    • /
    • pp.416-422
    • /
    • 2006
  • With the increasing demand for renewable energy, distributed power included in fuel cells have been studied and developed as a future energy source. For this system, a power conversion circuit is necessary to interface the generated power to the utility. In many cases, a high step-up dc/dc converter is needed to boost low input voltage to high voltage output. Conventional methods using cascade dc/dc converters cause extra complexity and higher cost. The conventional topologies to get high output voltage use flyback dc/dc converters. They have the leakage components that cause stress and loss of energy that results in low efficiency. This paper presents a high boost converter with a voltage multiplier and a coupled inductor. The secondary voltage of the coupled inductor is rectified using a voltage multiplier and series-connected with the boost voltage of primary voltage of the coupled inductor. Therefore, high boost voltage is obtained with low duty cycle. Theoretical analysis and experimental results verify the proposed solutions using a 300W prototype.

A Development of the Low Energy Large Aperture Electron Beam Generator (저에너지 대면적 전자빔 발생장치 개발(II))

  • Woo, Sung-Hun;Lee, Kwang-Sik;Lee, Dong-In;Cho, Chu-Hyun;Choi, Young-Wook;Lee, Hong-Sik;Abroyan, M.
    • Proceedings of the KIEE Conference
    • /
    • 1998.07e
    • /
    • pp.1767-1769
    • /
    • 1998
  • We have established a pulsed electron beam generation system with an energy of 200[keV], pulse repetition rate of 200[Hz], and several tens of [${\mu}s$] pulse width. The system is characterized by a cold cathode that is simpler than the hot cathode. Target object does not need to be scanned because of large aperture electron beam of 300[$cm^2$]. Electron source is secondary electrons that are generated when the ions from the glow discharge collide on the cathode surface. In this paper, the discharge current characteristics are investigated experimentally as a function of He gas pressure in order to obtain stable glow discharge. And computer simulations are carried out as a preliminary study for the development of low energy large aperture electron beam generator. The variation of electon beam current is investigated as a function of rising time of high voltage when 20[kV] potential is applied in 20[mTorr] pressure.

  • PDF

Regeneration and selection of root rot resistant Coleus forskohlii A threatened medicinal plant

  • M.George, Manju;Subramanian, R.B.;A.Prajapati, Hiren
    • Proceedings of the Plant Resources Society of Korea Conference
    • /
    • 2000.10a
    • /
    • pp.96-113
    • /
    • 2000
  • Coleus forskohlii Briq. of the family Lamiaceae yields a valuable secondary metabolite known as forskolin which is a labdane diterpenoid. Coleus forskohlii is the only known source of this compound. Forskolin is used in medicine for the treatment of glaucoma, congestive cardiomyopathy and asthma. Morphogenic callus was induced from young leaves on MS medium augmented with NAA and BA. These calli, when subcultured on MS with KN alone gave rise to shoots. The regenerated shoot developed good root system on MS medium fortified with NAA. The fully grown plantlets were transferred to soil for acclimatization. Coleus plant is mainly infected by a fungi Lasiodiplodia theobromae which causes root of disease. The fungal culture filterate (FCF) of Lasiodiplodia theobromae, has been used in regeneration media to find the MIC and further to select resistant plants to the pathogen. In the present study 40% FCF in the medium showed maximum inhibition and is there fore considered as the MIC level of Coleus forskohlii. This data could prove to be useful for the future for selecting a resistant C,forskohlii plant against the root disease caused by L.theobromae.

  • PDF