• 제목/요약/키워드: H-continuous

검색결과 2,171건 처리시간 0.029초

신평·장림 산단 인근 주민의 PAHs 및 VOCs 노출 (Exposure to PAHs and VOCs in Residents near the Shinpyeong·Jangrim Industrial Complex)

  • 윤미라;조혜정;김근배;장준영;이철우;이보은
    • 한국환경보건학회지
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    • 제47권2호
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    • pp.131-143
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    • 2021
  • Objectives: This study aims to investigate the atmospheric concentration of polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs) and the urinary concentration of biomarkers in residents near the Shinpyeong·Jangrim Industrial Complex to compare them with those of residents in a control area. Methods: Hazardous air pollutants (PAHs and VOCs) were measured in an exposure area (two sites) and a control area (one site). Urine samples were collected from residents near the industrial complex (184 persons) and residents in the control area (181 persons). Multiple linear regression analysis was used to identify which factors affected the concentration of PAHs and VOCs metabolites. Results: The average atmospheric concentration of PAHs in Shinpyeong-dong and Jangrim-dong was 0.45 and 0.59 ppb for pyrene, 0.15 and 0.16 ppb for benzo[a]pyrene, and 0.29 and 0.35 ppb for dibenz[a,h]anthracene. The average atmospheric concentration of VOCs was 1.10 and 0.99 ppb for benzene, 8.22 and 11.30 ppb for toluene, and 1.91 and 3.05 ppb for ethylbenzene, respectively. The concentrations of PAHs and VOCs in residents near the Shinpyeong·Jangrim Industrial Complex were higher than those of residents in the control area. Geometric means of urinary 2-hydroxyfluorene, 1-hydroxypyrene, methylhippuric acid, and mandelic acid concentrations were 0.45, 0.22, 391.51, and 201.36 ㎍/g creatinine, respectively. Those levels were all significantly higher than those in the control area (p<0.05). In addition, as a result of multiple regression analysis, even after adjusting for potential confounding factors such as gender and smoking, the concentration of metabolites in urine was high in residents near the Shinpyeong·Jangrim Industrial Complex. Conclusion: The results of this study show the possibility of human exposure to VOCs in residents near the Shinpyeong·Jangrim Industrial Complex. Therefore, continuous monitoring of the local community is required for the management of environmental pollutant emissions.

초미세습식분쇄공정의 공정변수에 따른 해조칼슘의 입자크기 분석 (Preparation of Seaweed Calcium Microparticles by Wet-grinding Process and their Particle Size Distribution Analysis)

  • 한민우;윤광섭
    • 산업식품공학
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    • 제13권4호
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    • pp.269-274
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    • 2009
  • 습식분쇄의 최적조건을 얻고자 부형제 종류, 농도, 습식 분쇄시 rotor speed, bead size, feed rate, 분쇄회수를 달리하여 분쇄한 결과, 부형제로는 gum arabic을 사용하여 5%의 농도로 첨가할 때 가장 좋은 분쇄효과를 나타내었다. Rotor speed를 달리하여 습식분쇄한 결과, rotor speed가 증가할수록 좋은 결과를 나타내어 4,000 rpm에서 가장 우수한 것으로 나타났다. 원료와 직접 부딪혀 분쇄를 하게 되는 bead는 0.4 mm의 크기를 사용하였을 때 가장 작은 사이즈로 분쇄되는 것으로 나타났다. 분쇄가 이루어지는 chamber내에 원료를 공급하는 비율에 따른 결과에서는 40 L/h 의 속도로 공급했을 때 가장 작은 입도분포를 보였다. 분쇄회수에 따른 영향은 횟수에 따라서는 8회 이상으로 분쇄하였을때 0.6 $\mu$m이하의 입도분포가 90% 이상으로 나타나 10회를 분쇄하였을때 가장 좋은 효과를 나타내었다. 연속운전과 비연속운전의 비교에서는 연속운전이 더 효율적이었으며 부형제 종류에 따른 영향은 gum arabic을 첨가하여 분쇄하였을때 가장 우수한 결과를 나타내었다. 따라서 적절한 농도와 종류의 부형제 사용과 rotor speed, bead size, feed rate, 용매와의 혼합비의 최적공정을 수립한 습식 분쇄기술로 초미세액상칼슘의 제조가 가능하였고, 습식분쇄기술을 식품가공기술로 활용할 수 있는 가능성을 확보하였다.

포기김치와 맛김치의 미생물학적 및 이화학적 품질 특성 비교 (Comparison of Mcrobial and Physicochemical Properties between Pogi Kimchi and Mat Kimchi)

  • 문은우;김수연;당윤미;박보연;박은진;송혜연;양지수;윤소라;서혜영;하지형
    • 한국식생활문화학회지
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    • 제34권2호
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    • pp.217-223
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    • 2019
  • This study aimed to evaluate the characteristic differential between whole cabbage kimchi (pogi kimchi) and sliced cabbage kimchi (mat kimchi) during kimchi fermentation at $6^{\circ}C$. The difference of microbial and physicochemical properties was investigated until 6 weeks. For the changes in the microbial flora, both kimchi samples exhibited a continuous increase in total aerobic bacteria and lactic acid bacteria (LAB) population size up to 2 weeks followed by a stationary phase until 5 weeks. Interestingly, the number of LAB of mat kimchi was overall higher than that of pogi kimchi during kimchi fermentation. We speculate that mat kimchi has in a more advantageous growth condition than pogi kimchi for microbial growth because small kimchi cabbage size appropriately derives nutritional supply in order to increase the LAB growth. During lactic fermentation at $6^{\circ}C$, physicochemical changes in the pH, salinity, and titratable acidity was observed to be no significant differences between two types of kimchi. Furthermore the contents of organic acids such as oxalic acid, citric acid, malic acid, lactic acid, fumaric acid, and acetic acid was not significantly different (p>0.05) between both kimchi samples as well as the contents of total free amino acid.

Salivary Flow According to Elderly's Whole Health and Oral Health Status: According to Application of Oral exercise and Salivary Gland Massage

  • Oh, Ji-Young;Noh, Eun-Mi;Park, Hye-Young;Lee, Min-Kyung;Kim, Hye-Jin
    • 대한의생명과학회지
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    • 제25권3호
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    • pp.218-226
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    • 2019
  • In old age, measures to cope with the natural phenomenon of aging and various diseases of the elderly due to the deterioration of physical function are also a challenge for this society. While interest in systematic health is increasing, it is true that awareness and interest in oral-related diseases is relatively lacking. This study aims to present basic data necessary to improve the quality of life for senior citizens aged 65 or older by improving the oral dryness caused by systemic health. By research method, improve oral dryness caused by whole-body health with the elderly over 65 and promote their oral health, inducing the increase of the salivary flow rate through oral health care education, oral exercise, and salivary gland massage. First, on the DMSQ according to the general characteristics of the elderly, the recognition of the whole body and oral health status, independent sample t-test and One-way ANOVA were conducted. Second, on changes in the salivary flow rate and saliva pH according to the general characteristics of the elderly, recognition of oral and whole-body health status, and whole-body health, paired samples t-test was conducted. Studies have shown that salivary gland flow increased significantly after oral exercise and salivary gland massage, the salivary flow rate significantly increased. In all variables of the recognition of the oral health status, the salivary flow rate increased after oral exercise and salivary gland massage, and in the whole-body health, regardless of hypertension, diabetes, cardiovascular disorders, and osteoporosis, the salivary flow rate increased after oral exercise and salivary gland massage, and the salivary flow rate increased after oral exercise and salivary gland massage if the subjects responded that they did not have thyroid abnormality, anemia, abnormalities of breathing, hypotension, gastrointestinal disturbance, or kidney diseases. As a comprehensive analysis of this study, many felt oral dryness when they had a problem with the whole-body health, and many felt oral dryness when they had a problem with oral health cognition. After applying oral exercise and salivary gland massage as intervention methods in the oral health care for the elderly, the salivary flow rate significantly increased, and it is judged that the methods were very effective for controlling oral dryness. Furthermore, it is judged that the factors affecting oral health, whole-body health, and oral dryness would be identified, which would be helpful for the promotion of whole-body health and oral health. It is judged that continuous research would be needed so that measures for the application of the oral care program and system for the elderly would be prepared in the future.

휘발성 유기화합물의 실시간 모니터링을 위한 휴대형 GC의 성능 평가 (Performance Evaluation of a Portable GC for Real-time Monitoring of Volatile Organic Compounds)

  • 유동욱;선영식;오준식;이봉윤;김현식;정광우
    • 대한화학회지
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    • 제64권6호
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    • pp.327-333
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    • 2020
  • 대기 중 미량의 휘발성 유기화합물을 실시간으로 측정할 수 있는 휴대형 GC의 성능을 평가하였다. 휴대형 GC의 크기는 35 × 26 × 15 ㎤, 무게는 5 kg으로 소형·경량이고, 24 VDC, 1 A (최대 3.2 A)의 저전력을 소모하며 공기를 운반 기체로 사용하므로 별도의 가스 실린더를 필요로 하지 않는다. 벤젠, 톨루엔, 에틸벤젠, 자일렌 1 ppmv와 20 ppmv 시료의 크로마토그램에 대한 피크 면적의 상대표준편차(RSD)는 각각 3.79%, 0.48% 이하이고, 머무름 시간의 RSD는 각각 0.40%와 0.08% 이하로 우수한 재현성을 보였다. 또한 방법검출한계(MDL)는 0.09 ppmv로 낮은 검출한계를 나타냈다. 길이 30 m, 내경 0.28 mm의 분리 컬럼을 사용하여 10분 이내의 측정 조건에서 구한 피크용량과 분해능은 다양한 혼합 샘플도 정량 및 정성 분석이 가능함을 입증하였다. 특히 27시간 동안 연속적으로 80회의 분석을 수행하였을 때 관찰된 크로마토그램의 피크 세기와 머무름 시간의 RSD가 각각 2.4%, 0.5% 이하로 좋은 재현성을 보였다. 따라서 본 연구의 휴대형 GC는 실내외 그리고 산업 현장에서 배출되는 휘발성 유해가스의 탐지는 물론 화학 물질의 유출사고에 대응하여 실시간 모니터링 할 수 있는 측정 장비로 활용될 수 있으리라 기대된다.

마을 내 잔존 노거수의 생육현황 및 실태진단 - 경주시 현곡면을 중심으로 - (Diagnosis of the growth status and actual condition of the remaining old trees in the village - Focused on Hyeongok-myeon in Gyeongju-si -)

  • 김영훈;덩베이지아;천겅;유주한
    • 한국환경복원기술학회지
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    • 제23권6호
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    • pp.109-123
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    • 2020
  • The purpose of this study is to provide basic data for the establishment of future countermeasures by diagnosing the growth status and actual condition of undesignated old trees distributed in Hyeongok-myeon, Gyeongju, Gyeongsangbuk-do. The number of old trees surveyed was 2 weeks in Gajeong-ri, 2 weeks in Haguri, 3 weeks in Nae-Tae-ri, 1 week in Nawon-ri, 6 weeks in Oryu-ri, 3 weeks in Sangguri, and 2 weeks in Sohyeon-ri, The trees species composition was 6 trees Celtis sinensis Pers., 1 Diospyros lotus L. trees, 4 trees Salix chaenomeloides Kimura trees, 2 Styphnolobium japonicum L. trees, and 7 Zelkova serrata (Thunb.) Makino trees. Growth status is 7.1~22.0m in height, 14.6~25.1m in long axis, 10.2~19.2m in short axis, root diameter is 76.0~236.4cm, diamter at breast height is 67.0~220.0cm, soil acidity is pH4.9~7.0, soil The hardness was measured to be 4.0-27.0mm. The result grade of the scoring data of health information is represented by monitoring generally, monitoring critically, and absolute monitoring, and it was confirmed that out of the 20 trees population in Hyeongok-myeon, the general monitoring grade was 7 weeks, the major monitoring grade was 13 weeks, and there was no absolute monitoring grade. Accordingly, the number of old trees of the general surveillance level was maintained at the current level, and ecological surgical operations were introduced for the major surveillance level, but the case of village forests should be different, and sequential treatments were the old tree urgently needed. The level and bark of the target tree, the state of the crown, the root exposure, the presence of pests and pests, the vitality and the ground condition, the degree of pollution are normal, poor, or very poor, operation and protection management, soil improvement, removal of cover, and disinfection were urgently needed for the old trees with the surveyed data. In order to compensate for these matters, continuous monitoring and management measures for the old number should be sought.

국내산 양식 뱀장어에서 항생제 내성 비브리오 세균 분리 및 특성 (Isolation and Characterization of Antibiotic Resistant Vibrio Strains from Japanese Eel (Anguilla Japonica) Cultured in Korea)

  • 박선영;김지형;전진우
    • 현장농수산연구지
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    • 제22권2호
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    • pp.51-58
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    • 2020
  • 2019년 11월, 국내의 뱀장어 양식장에서 양식 중이던 뱀장어가 피부궤양 및 피부의 점상출혈 소견을 보이며 지속적으로 폐사하였다. 일련의 폐사는 2019년 11월부터 12월까지 지속되었다. Vibrio 속 균주 1E1-2는 첫 번째 폐사 사례에서 폐사한 뱀장어의 출혈성 복수에서 분리되었고 균주 2A3-1는 두 번째 폐사 사례에서 폐사한 뱀장어의 복수에서 분리되었으며 균주 3K1-2는 세 번째 폐사 사례에서 폐사한 뱀장어의 신장에서 분리되었다. 16S rRNA gene 시퀀스 분석으로, 분리균주 1E1-2와 3K1-2가 V. fluvialis NBRC 103150T와 가장 높은 유사도를 나타내며 V. fluvialis로 동정되었으며, 균주 2A3-1는 V. plantisponsor NBRC103148T와 가장 높은 유사도를 나타내며 V. plantisponsor로 확인되었다. 항생제 감수성 실험 결과로, V. fluvialis 1E1-2는 tetracycline과 chloramphenicol에 대하여 중등도의 감수성을 보였고 trimethoprim-sulfamethoxazole에 대하여 내성을 나타내었다. V. plantisponsor 2A3-1는 ciprofloxacin과 levofloxacin에 대하여 중등도의 감수성을 나타내었고 trimethoprim-sulfamethoxazole에 대하여 내성을 나타내었다. V. fluvialis 3K1-2는 tetracycline에 대하여 중등도의 감수성을 나타내었고 ampicillin과 trimethoprim-sulfamethoxazole에 대하여 내성을 나타내었다. 이는 국내 양식 뱀장어에서의 항생제 내성 비브리오 감염증 사례로, 의미 깊은 보고라고 할 수 있다.

Mg-Fe 이중층수산화물로 제조한 분말상과 입상 안정화제의 비소 오염토양 안정화 기작 (Stabilization Mechanisms of Powdered and Bead Type Stabilizer Made of Mg-Fe Layered Double Hydroxide (LDH) for the Arsenic Contaminated Soil)

  • 김선희;김경태;오유나;한이경;이민희
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제27권4호
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    • pp.49-62
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    • 2022
  • The magnesium and iron-based layered double hydroxide (Mg-Fe LDH) was synthesized by the co-precipitation process and the bead type LDH (BLDH, 5~6 mm in diameter) was manufactured by using the Mg-Fe LDH and the starch as a binder. To evaluate the feasibility of the BLDH as the As stabilizer in the soil, various experiments were performed and the As stabilization efficiency of the BLDH was compared to that of powdered type LDH (PLDH, <149 ㎛ in diameter). For the As sorption batch experiment, the As sorption efficiency of both of the PLDH and the BLDH showed higher than 99%. For the stabilization experiment with soil, the As extraction reducing efficiency of the PLDH was higher than 87%, and for the BLDH, it was higher than 80%, suggesting that the BLDH has similar the feasibility of As stabilization for the contaminated soil, compared to the PLDH. From the continuous column experiments, when more than 7% BLDH was added into the soil, the As stabilization efficiency of the column maintained at over 91% for 7 pore volume flushing (simulating about 21 months of rainfall) and slowly decreased down to 64% after that time (to 36 months) under the non-equilibrium conditions. Results suggested that more than 7% of BLDH added in As-contaminated soil could be enough to stabilize As in soil for a long time. The main As fixation mechanisms on the LDH were also identified through the X-ray fluorescence (XRF), the X-ray diffraction (XRD), and the Fourier transform infrared (FT-IR) analyses. Results showed that the LDH has enough of an external surface adsorption capacity and an anion exchange capability at the interlayer spaces. Results of SEM/EDS and BET analyses also supported that the Mg-Fe LDH used in this study has sufficient porous structures and outer surfaces to fix the As. The reduction of carbonate (CO32-) and sulfate (SO42-) anions in the LDH after the reaction between As and the LDH was observed through the FT-IR, the XRF, and the XRD analyses, suggesting that the exchange of some of these anions with the arsenate (H2AsO4- or HAsO42-) occurs at the LDH interlayers during the stabilization process in soil.

중증 화상환자에서 다약제내성그람음성균의 Colistin 치료 (Intravenous Colistin Therapy for Multidrug-Resistant Gram-Negative Bacterial Infections in Major Burn Injuries)

  • 조기원;윤재철;전진우;김영민;임해준;김도헌;허준;전욱;조용석
    • 대한화상학회지
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    • 제22권1호
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    • pp.1-9
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    • 2019
  • Purpose: The aim of this study was to investigate the characteristics of Acute Kidney Injury Network (AKIN)-defined nephrotoxicity in patients undergoing intravenous colistimethate sodium (CMS) therapy for major burns. Methods: This retrospective study included burn patients who received more than 48 h of intravenous CMS between September 2009 and December 2015. Data collection was performed using the institution's electronic medical record system. Patients assigned to the developed nephrotoxic group experienced aggravation of current AKIN stage during CMS treatment; those assigned to the non-nephrotoxic group experienced no change in current or exhibited improved AKIN stage during CMS therapy. Results: A total of 306 patients were included in this study. All patients were grouped according to AKIN stage: AKIN 0 (n=152); AKIN 1 (n=6); AKIN 2 (n=9); AKIN 3 (n=139). The baseline creatinine (Cr) level was 0.73 mg/dL. The incidence of nephrotoxicity was 50.3% according to AKIN stage; overall mortality was 45.8%. The non-nephrotoxic group consisted of 127 (74.7%) patients and 43 (25.3%) were in the developed nephrotoxic group. In patients requiring continuous renal replacement therapy (CRRT), baseline Cr level was 0.83 mg/dL, pre-CMS Cr level was 1.17 mg/dL, and post-CMS Cr level was 1.34 mg/dL. Conclusion: CMS can be administered without signs of nephrotoxicity for a certain period (approximately 1 week), it can be used relatively safely for 2 weeks. Application of CMS is a reasonable option for treating infections caused by multi-drug resistant gram-negative bacteria in patients with major burns. The caution should be exercised nevertheless.

Opening New Horizons with the L4 Mission: Vision and Plan

  • Kyung-Suk Cho;Junga Hwang;Jeong-Yeol Han;Seong-Hwan Choi;Sung-Hong Park;Eun-Kyung Lim;Rok-Soon Kim;Jungjoon Seough;Jong-Dae Sohn;Donguk Song;Jae-Young Kwak;Yukinaga Miyashita;Ji-Hye Baek;Jaejin Lee;Jinsung Lee;Kwangsun Ryu;Jongho Seon;Ho Jin;Sung-Jun Ye;Yong-Jae, Moon;Dae-Young Lee;Peter H. Yoon;Thiem Hoang;Veerle Sterken;Bhuwan Joshi;Chang-Han Lee;Jongjin Jang;Jae-Hwee Doh;Hwayeong Kim;Hyeon-Jeong Park;Natchimuthuk Gopalswamy;Talaat Elsayed;John Lee
    • 천문학회지
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    • 제56권2호
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    • pp.263-275
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    • 2023
  • The Sun-Earth Lagrange point L4 is considered as one of the unique places where the solar activity and heliospheric environment can be observed in a continuous and comprehensive manner. The L4 mission affords a clear and wide-angle view of the Sun-Earth line for the study of the Sun-Earth and Sun-Moon connections from he perspective of remote-sensing observations. In-situ measurements of the solar radiation, solar wind, and heliospheric magnetic field are critical components necessary for monitoring and forecasting the radiation environment as it relates to the issue of safe human exploration of the Moon and Mars. A dust detector on the ram side of the spacecraft allows for an unprecedented detection of local dust and its interactions with the heliosphere. The purpose of the present paper is to emphasize the importance of L4 observations as well as to outline a strategy for the planned L4 mission with remote and in-situ payloads onboard a Korean spacecraft. It is expected that the Korean L4 mission can significantly contribute to improving the space weather forecasting capability by enhancing the understanding of heliosphere through comprehensive and coordinated observations of the heliosphere at multi-points with other existing or planned L1 and L5 missions.