Trophodynamics of euphausiids in the Amundsen Sea during the austral summer by fatty acid and stable isotopic signatures

Ko, A.R.,Yang, E.J.,Kim, M.S.,Ju, S.J. Pergamon Press 2016 Deep-sea research. Part II, Topical studies in oce Vol.123 No.-

The Amundsen Sea is characterized by a continental shelf, long-term sea ice, and many coastal polynyas with high biological productivity. Euphausia superba and Euphausia crystallorophias, which are dominant Antarctic krill, are major prey for most predators, such as fishes, birds, and marine mammals. An understanding of the feeding ecology of krill may provide the information for the structure and function of the Amundsen Sea ecosystem. Thus, we applied two biochemical approaches (fatty acids and stable isotopes) to determine the trophodynamics of adult krill in the Amundsen Sea. There were no significant differences in lipid contents between the two species, but the dominant storage lipids were different. Triacylglycerol (TAG) was dominant in E. superba, but wax esters (WE) were dominant in E. crystallorophias due to their different living strategies. Furthermore, the lipid content of E. crystallorophias displayed a spatial variation, being highest on the glacial edge. It was difficult to understand the feeding strategy and food source using only the fatty acid compositions of krill and in situ particulate organic matter. However, we found that specific FA ratios (18:1ω9/18:1ω7 and PUFA/SFA) and the nitrogen isotope ratio (δ<SUP>15</SUP>N) provide more insight into the feeding ecology of krill, such as feeding strategy and trophic position. These ratios suggest that E. crystallorophias consistently showed a higher degree of carnivorous feeding than E. superba in the Amundsen Sea during the austral summer. In conclusion, adult E. superba might more directly obtain their energy from in situ primary producers in the open sea, but, in the Amundsen Sea Polynya, adult E. crystallorophias seems to obtain their energy mainly through the microbial loop (microzooplankton). If so, E. crystallolophias would be a key player not only to transfer the energy from microbes to higher trophic levels but also to control the carbon and nitrogen cycle in the Amundsen Sea Polynya.

Study of sulfur-resistant Ni-Al-based catalysts for autothermal reforming of dodecane

Jung, S.Y.,Ju, D.G.,Lim, E.J.,Lee, S.C.,Hwang, B.W.,Kim, J.C. Pergamon Press ; Elsevier Science Ltd 2015 International journal of hydrogen energy Vol.40 No.39

Diesel fuel has merits such as good refueling infrastructure and high hydrogen density, but it also contains small amounts of sulfur compounds that deactivate reforming catalysts by sulfur poisoning. In this work, various promoters such as La (NAL10-PM), Ce (NAC10-PM), and Fe (NAF10-PM) were used to improve the catalytic activities of Ni-Al-based reforming catalysts in the presence of sulfur compounds. Various Ni-Al-based catalysts were prepared by a polymer-modified incipient method using polymethyl methacrylate (PMMA). The tests were performed in a fixed-bed reactor, and dodecane and dibenzothiophene (DBT) were used as the surrogate diesel fuel and sulfur compound, respectively. In the presence of 100 ppm DBT, the NAF10-PM catalyst maintained 80% dodecane conversion without deactivation for 6 h, although the other catalysts were deactivated; the conditions were S/C = 1.23, O<SUB>2</SUB>/C = 0.25, 750 <SUP>o</SUP>C, and a gas hourly space velocity of 12,000 h<SUP>-1</SUP>. Scanning electron microscopy-energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy showed that catalyst deactivation was caused by the deposition of large amounts of graphitic carbon on the catalyst surface in the presence of 100 ppm DBT. Lesser graphitic carbon was deposited on the NAF10-PM catalyst than the other catalysts, and catalytic activity was maintained even in the presence of DBT. In addition, X-ray diffraction showed the formation of a Ni-Fe alloy in the NAF10-PM catalyst. It is suggested that the Ni-Fe alloy prevented the deposition of graphitic carbon, and thus catalyst deactivation. In summary, the catalytic activity for autothermal reforming of dodecane on the Fe-promoted NAF10-PM catalyst was excellent, and no deactivation occurred in the presence of 100 ppm DBT.

간호대학생의 이론・실습 성적과 임상수행능력의 관련성 : 성인간호학 교과목을 중심으로

권현진,김다영,김민정,김소현,박예담,박지원,왕서현,유영주,이재현,주가은,신수진 이화여자대학교간호학회 2020 이화간호학회지 Vol.- No.54

Purpose: This study aimed to explore the relationship among score of theory course, score of practicum course and clinical practice ability by the course, Adult Health Nursing. Methods: A descriptive research was conducted using questionaries. Data were collected from September 25 to October 2, 2019. Participants were 67 nursing students at one university in Seoul on their junior year who have experienced clinical settings. The collected data were analyzed by t-test, ANOVA, Cohen’s Kappa, and Scheffe’s test using SPSS 25.0 version program. Results: Participants were given a quartile number from 1 to 4 respectively according to their scores of theory course those of practicum course. The total mean score of clinical practice ability was 3.61, with a perfect score of 5. The scores of theory course and practicum course showed slight correlation(Cohen’s Kappa=.168). However, significant correlation did not existed among score of theory course, score of practicum course and clinical practice ability. Conclusion: The result showed that score of theory course, score of practicum course and clinical practice ability have no significant correlation. However, its finding suggests the necessity of further research about various approach and new evaluation methods needed in order to improve nursing students’ competency.

Molecular Analysis of Prion Protein Gene (PRNP) in Korean Patients with Creutzfeldt-Jakob Disease

Jeong, B.-H Korean Academy of Medical Science 1998 Journal of Korean medical science Vol.13 No.3

초음파 가진을 이용한 2-유체 노즐의 효율 향상

주은선,나우정,정진도,송민근,이경열 한국농업기계학회 2002 바이오시스템공학 Vol.27 No.4

Adult T-cell Leukemia/Lymphoma with Features of CD30-Positive Anaplastic Large Cell Lymphoma

Soon Nam Lee Korean Academy of Medical Science 1997 Journal of Korean medical science Vol.12 No.4

초음파 적용 상온연무기용 2-유체 노즐의 분무입경 측정

나우정,주은선,정진도,송민근,이경열 경상대학교 농업생명과학연구원 2001 농업생명과학연구 Vol.35 No.-

상온연무기의 연무입자의 미립화에 대한 초음파 에너지의 효과를 구명하기 위하여 상온 연무기용 2-유체 노즐에 초음파 비가진 시의 상용분무, 분무노즐에 초음파 진동을 기계적 진동으로 주는 간접진동분무, 초음파를 분무액체에 직접 가하는 개질분무, 간접진동분무와 개질분무를 동시에 가하는 간접진동 및 개질법 겸용분무에 대하여 입경을 측정하였다. 분무방향 축과 반경방향 전 영역에 걸쳐서 사우터 평균지름(Sauter's mean diameter)을 측정한 결과 초음파 비가진 시인 상용분무시의 입경이 가장 크게, 간접진동 및 개질법 겸용의 경우가 가장 작게 나타났다. To figure out the effect of ultrasonic energy on the atomization of spray droplets from a twin-fluid nozzle used for cold-fog machine, spray droplets were measured according to the four experimental conditions; conventional spray where no ultrasonic energy is added, indirect vibration method where ultra vibration is added to the body of nozzle, liquid-property-change method where ultrasonic energy is added directly into the spray liquid, and combined addition method where indirect vibration method and liquid-property-change method are applied simultaneously. For all the regions according to the distance from the nozzle tip and for all radial regions, the poorest atomization was observed for the conventional spray condition and the best atomization was observed for the combined method conditions.

초음파에 의한 액체 미립화 입경 분포도에 관한 연구

최우창,주은선,송민근,박영호 慶尙大學校生産技術硏究所 1998 生産技術硏究所論文集 Vol.14 No.-

A Study on size distributions of the liquid atomization by ultrasonic was carried out using 3 methods, such as direct vibration, aerosol and improvement method. Distilled water and city water were selected as the reference liquids and gasoline, kerosene and petroleum as fuel liquids. Two kinds of ultrasonic transducers, with 28kHz and 2MHz were used. Characteristics and phenomena on ultrasonic atomization were observed and examined relatively according to influx and liquid load by using the Malvern system. In results, The best uniformity of particle size was achieved by the direct vibration method, and their mean size was 10 times larger than that of the aerosol method.

Characterization of CBD-CdSe1-ySy deposited at low-temperature for photovoltaic applications

J.I. Contreras-Rascón,J. Díaz-Reyes,J.E. Flores-Mena,M. Galvan-Arellano,L.A. Juárez-Morán,R.S. Castillo-Ojeda 한국물리학회 2015 Current Applied Physics Vol.15 No.12

We present the structural and optical characterization of cadmium selenide sulphur (CdSe1-ySy) deposited by chemical bath deposition (CBD) technique at low-temperature (20 ± 2 ℃). The sulphur molar fraction is varied from 0 to 42.13%. The chemical stoichiometry is estimated by energy-dispersive X-ray spectroscopy (EDS). The CdSe1-ySy shows hexagonal wurtzite crystalline phase, which was found by X-ray diffraction (XRD) analysis and it was confirmed by Raman spectroscopy. The average grain size of the CdSe1-ySy films was ranged from 1.20 to 1.68 nm that was determined by Debye-Scherrer equation from W(002) direction and it was confirmed by high resolution transmission electron microscopy (HRTEM). This average grain size indicates a high quantum confinement because of it is smaller than the Bohr radii of CdS (2.8 nm) and CdSe (4.9 nm). Raman spectra show two dominant vibrational bands about 208 and 415 cm-1 associated at CdSe-1LO-like and CdSe-2LO-like. By transmittance measurements at room temperature are found that the optical band gap energies vary from 1.86 to 2.16 eV in the range of investigated sulphur molar fraction. Room temperature photoluminescence shows radiative bands in the visible range and a dominant band in the UV range, approximately 3.0 eV, which can be associated with a radiative transition, bound exciton to donor impurity.

Cr-doped BiYO3 photocatalyst for degradation of oxytetracycline under visible light irradiation

Hernández-Arellano Diana L.,Durán-Álvarez Juan C.,Cortés-Lagunes Silvana,Zanella Rodolfo,Soto Tania E.,López-Juárez Rigoberto 한국세라믹학회 2023 한국세라믹학회지 Vol.60 No.1

Chromium-doped BiYO3 powders were synthesized by the Pechini method at low temperature between 400 and 800 °C for 1 h. From the XRD results it was observed the coexistence between tetragonal and cubic phases for samples calcined at 400 °C for 1 h. Meanwhile, for samples calcined at 600 and 800 °C, a single cubic phase was observed. The powders consisted of agglomerates of nanocrystals as shown in the SEM and TEM images. The specific surface area was in the order of 3.01–7.74 m2 g−1, obtained from BET analysis. The band gap of BiYO3 and Cr-doped BiYO3 was < 2.21 eV which corroborates that these materials absorb light in the visible region of the electromagnetic spectrum. The photocatalytic decomposition of oxytetracycline was successfully achieved using Cr-doped BiYO3, where the best performance was obtained with BiY0.98Cr0.02O3 ceramic powders calcined at 800 °C for 1 h. For this composition the removal of oxytetracycline after 240 min of visible light irradiation was 100% of degradation and 75% of mineralization. The photocatalytic process was driven by the photo-holes, as a negligible production of ·OH radicals was observed in tests using scavengers. The photocatalytic activity of the BiY0.995Cr0.005O3 and BiY0.98Cr0.02O3 materials was corroborated under more realistic conditions, using tap water and trace concentration of the antibiotic. The high stability of the photocatalyst was observed through four consecutive reaction cycles. The results demonstrate that the Cr-doping has clearly improved the catalytic performance of BiYO3 for degradation of oxytetracycline under visible light irradiation.