Influence of the axial dispersion on immobilized enzyme catalytic bed was investigated in order to examine the kinetic behavior of the biocatalysis. The enzyme employed in this study was the tyrosinase(EC 1.14.18.1) immobilized on carbon support : this system requires two substrates of phenol and oxygen. This enzyme has potential application for phenol degradation in waste water. A simulated reactor was a packed-bed reactor of 2.54cm in diameter and 10cm long, loaded with the immobilized carbon particle with an average diameter of $550{\mu}m$. A phenol feed in the strength of 55.5mM(5220ppm) was used to observe the behavior of the immobilized enzyme column at three different dissolved oxygen levels of 0.08445mM(2.7ppm), 0.1689mM(5.4ppm) and 0.3378mM(9.5ppm) with the flow rates in the range of 60(1mL/s) to 180mL/min(3mL/s). Examination of the Biot number and Damkolher numbers of the immobilized system enables us to eliminate the contribution of external mass transfer to set of differential equations derived from the dispersion model. Solution of the equation was finally obtained numerically with the application of the Danckwert boundary conditions and the assumed zero-and first order rates on the non-linear two substrate enzyme kinetics. Higher conversion of phenol was observed at the low flow rates and at the higher oxygen concentration. Comparison of axial dispersion and plug flow model showed that no detectable difference was observed in the column outlet conversion between the axial and the plug flow models which was in complete agreement with the previous studies.
Kim, Kye-Hoon;Kim, Kwon-Rae;Kim, Hyuck-Soo;Lee, Goon-Taek;Lee, Keun-Hwa
Korean Journal of Soil Science and Fertilizer
/
v.43
no.3
/
pp.384-389
/
2010
Outbreak of contagious diseases to livestock animals is becoming prevalent worldwide and consequently, tremendous numbers of the infected or culled stocks are buried on the ground as the most common disposal method. The buried animals can generate a wide range of detrimental components such as leachate, nutrient salts, and pathogenic bacteria, consequently contaminating the surround environment. This implies that regular investigations are required to monitor any possible detrimental environmental aspect occurred around burial sites. Therefore, the current study was conducted to investigate whether the soil and groundwater nearby the burial sites had been contaminated by the substances originated from the burial sites, which can be applied for the establishment of the ideal burial site construction design and post management scheme. For this, two different burial sites located in Cheonan and Pyeongtaek were selected. Cheonan and Pyeongtaek sites were constructed in 2004 and 2008, respectively and both contained dead poultry infected by avian influenza (AI). Soil and groundwater samples were collected around the sites followed by determination of the nutrient concentrations and bacteria (Salmonella, Camphylobacter, and Bacillus) existence in both soil and groundwater. Some of the soil samples showed higher EC, $NH_4$-N, $NO_3$-N concentration compared to those of the background (control) soils. Also the concentration of $NH_4$-N in some of the groundwater samples appeared to exceed the USEPA guideline value for drinking water (10 mg $L^{-1}$). These results indicated that the soil and groundwater were influenced by the burial site originated nutrients. In the soil, Bacillus was isolated in most soil samples while there were no detections of Salmonella and Camplylobacter. Due to the Bacillus existing mainly as a spore in the soils, it was considered that the frequent detection of Bacillus in the soil samples was attributed to the nutrients originated from the burial sites.
The physicochemical properties of starches isolated from three kinds of waxy ricer were investigated. The average diammeter of Orchal starch granule was 3.6u, and those of Hangang and Baegoon starch granules were 4.8u and 5.6u, respectively. X-ray diffraction patterns of all samples were A types. Optical transmittance of starch suspensions was increased rapidly $60{\sim}62^{\circ}C$, $50{\sim}55^{\circ}C$ and $50{\sim}60^{\circ}C$ in Olchal, Hangang and Baegoon, respectively, and all of them exhibited maximum transmittance $75{\sim}80^{\circ}C$ in range. Initial gelationization temperature by means of amylogram pattern was $60{\sim}61^{\circ}C$, then, Olchal starch had a little higher temperature than others. Raising power of them was $260\sim220$, and then, Olchal starch has a little higher raising power. But, water binding capacity of Baegoon and Hangang were somewhat higher than that of Olchal. Blue values of Olchal and Hangang were similar with 0.13, and that of Baegoon was 0. 14. Alkari numbers of Olchal, Hangang and Baegoon were 4.2, 4.9 and 5.1. The degree of retrogradation of Hangang and Baegoon starch gels were somewhat higher than that of Olchal starch gel.
Purpose: To determine the clinical value of the Siewert classification for gastic-cancer patients in Korea, we evaluated and compared the clinicopathologic factors of type II and type III cancer. Materials and Methods: The medical records of 89 consecutive patients who had undergone surgery for an adenocarcinoma of the gastroesophageal junction (GEJ) at the Department of Surgery, Hanyang University Hospital, between Jun. 1992 and Dec. 2003 were reviewed retrospectively. Results: There were one patient with type I, 12 pateints with type II and 77 patients with type III. During the same period, 1,341 patients underwent surgery for a gastric carcinoma, so proportion of GEJ cancer being $6.6\%$. The median followup duration was 31 months (range: $2\∼135$ months), and the follow-up rate was $100\%$. Between type II and type III cancers, there were no significant differences in the clinicopathologic variables including age, sex, gross appearance, histologic type, depth of invasion, and pathologic stage. The longest diameter of the tumor was larger in type III ($6.1\pm2.1$ cm) than in type II ($3.9\pm1.1$ cm)(P=0.001). A total gastrectomy with Roux-en-Y esophagojejunostomy was done most frequently, while jejunal interposition was done in 3 cases of type II and 2 cases of type III. More than a D2 lymphadenectomy was done all cases. The numbers of dissected lymph nodes and metastatic lymph nodes in type II were 43.8 and 5.8 respectively, while they were 49.8 and 8.1 in type III, but the difference between the two groups were not statistically significant. The mean length of the proximal resection margin was $15\pm5$ mm in type II and $21\pm13$ mm in type III, but this difference was not statistically significanct. The time to recurrence after operation was 19.3 months in type II and 16.9 months in type III. The five-year survival rates of type II and III were $68.8\%\;and\;52.7\%$ respectively, but difference was not significant. Conclusion: There were no significant differences in the clinicopathologic variables, including survival rate, between type II and type III cancers in Korean patients According to these findings, it appears to be reasonable to classify type III cancer as a cardia cancer in a broad sense.
BACKGROUND: Today, environmentally friendly farming has become an important feature of agricultural policy. It promotes or sustains farming systems which protect and enhance the environment. This study was conducted to compare benthic invertebrate communities in an organic and a conventional paddy field in South Korea. METHODS AND RESULTS: Benthic invertebrates were collected at 11 regions of a rice paddy from June to August, 2009, 2010 and 2011. These comparisons undertaken using a community assessment approaches such as the number of individuals and species and community composition. Generally, the larger number of individuals and species of benthic invertebrates was observed in an organic paddy than in a conventional paddy field. Organic paddy fields could supported the wider range of species and abundance in aquatic invertebrates comparing to conventional paddy fields. Carrying capacity to support larger numbers of invertebrates also tends to be higher in organic paddy than in conventional paddy field. Specially, organic farming regions surrounded by forests were high quality habitat for benthic invertebrates than other surrounded regions such as grassland. CONCLUSION(S): We concluded that organic farming was more advantaged to benthic invertebrates than conventional farming. In order to improve biodiversity in rice paddy field, farming regimes without agricultural chemicals are recommended. The effect of organic management on biodiversity and abundance of benthic invertebrates could be maximized across highland farmland.
LEE Jae Chul;CHOO Hyo Sang;LEE Kyu Hyong;CHO Kyu Dae
Korean Journal of Fisheries and Aquatic Sciences
/
v.28
no.5
/
pp.624-634
/
1995
Tides at both of northern and southern entrances of Kamag Bay were compared by deploying tide gauges for 18 days during July-August 1994. To examine the response of the inner bay to the tidal waves through both entrances, a current meter was moored at the eastern pan of the inner bay. Current meter mooring failed at the northern entrance (Yosu) while the current data was collected for only 5 days at the southern site (Songdo). Maximum range was 357 and 352 cm at Yosu and Songdo, respectively. Respective amplitudes for M2, S2 Kl O1 tides of 95.5, 48.8, 20.5, 14.0cm at Yosu and 93.6, 47.2, 21.3, 13.1cm at Songdo yielded the form numbers of 0.23 and 0.24, respectively, both of which belong to the predominantly semidiurnal tide, Contributions from the overtides and compound tides were less than $4\%^ at both sites. Differences in Greenwich phase of major partial tides between two sites were negligible. Maximum speed of tidal current was about 100cm/sec at the southern entrance and about 40cm/sec at the inner bay. Residual current speed was 17cm/sec southwestward at the southern entrance and 0.9cm/sec southeastward at the inner bay. Temporal change in current at the inner bay showed that the wind had a significant influence upon the circulation in Kamag Bay.
Since April 2012, doctor fish in the breeding tank and in the quarantine tank in Hanwha Aquaplanet Yeosu Aquarium have been dying, accompanied by diffuse bleeding around the mouth, in the chin, and at the bottom of the abdomen. In this study, the cause of death would be examined through the bacteriological study of doctor fish and the rearing water quality in the aquarium. The water quality and the bacterial counts of the rearing water in the exhibit tank and in the quarantine tank were analyzed once a week, starting from August to November 2014. Water quality was measured based on the following data: temperature was in the range of 24.5~26.8℃, pH at 6.77~7.94, DO at 6.15~8.61 ppm, ammonia at 0~0.93 ppm, nitrite at 0.009~0.075 ppm, and nitrate at 1.1~40.9 ppm. Studies revealed that the differences in these water quality factors were not related to the death of doctor fish. Bacterial counts in the rearing waters of Garra rufa slightly increased to 103~104 CFU/ml, just before the death of the doctor fish. Twelve strains of bacteria were isolated from the dead fish and rearing waters. The isolates were identified as Aeromonas veronii, Citrobacter freundii, Pseudorhodoferax aquiterrae, Shewanella putrefaciens, and Vibrio anguillarum on the basis of 16S rRNA gene sequences. The most dominant species was C. freundii, which showed medium sensitivity to florfenicol and norfloxacin, and was resistant to amoxacillin, doxycycline, oxytetracycline, tetracycline, and trimethoprim. Ten isolates were confirmed to be pathogenic to the doctor fish. Doctor fish infected with C. freundii and S. putrefaciens showed high mortality in the experimental groups. These results indicate that the variation in bacterial numbers in the rearing water was related to the death of doctor fish. C. freundii and S. putrefaciens were directly implicated in causing the death of doctor fish in the aquarium.
Kim, Ji-Soo;Lee, Jae-Young;Seo, Yong-Seok;Ju, Hyeon-Tae
The Journal of Engineering Geology
/
v.23
no.4
/
pp.457-465
/
2013
We integrated and correlated datasets from surface and subsurface geophysics, drilling cores, and engineering geology to identify geological interfaces and characterize the joints and fracture zones within the rock mass. The regional geometry of a geologically weak zone was investigated via a fence projection of electrical resistivity data and a borehole image-processing system. Subsurface discontinuities and intensive fracture zones within the rock mass are delineated by cross-hole seismic tomography and analyses of dip directions in rose diagrams. The dynamic elastic modulus is studied in terms of the P-wave velocity and Poisson's ratio. Subsurface discontinuities, which are conventionally identified using the N value and from core samples, can now be identified from anomalous reflection coefficients (i.e., acoustic impedance contrast) calculated using a pair of well logs, comprising seismic velocity from suspension-PS logging and density from logging. Intensive fracture zones identified in the synthetic seismogram are matched to core loss zones in the drilling core data and to a high concentration of joints in the borehole imaging system. The upper boundaries of fracture zones are correlated to strongly negative amplitude in the synthetic trace, which is constructed by convolution of the optimal Ricker wavelet with a reflection coefficient. The standard deviations of dynamic elastic moduli are higher for fracture zones than for acompact rock mass, due to the wide range of velocities resulting from the large numbers of joints and fractures within the zone.
Objectives : Regulatory T cells can reduce inflammation and allergic reactions through their inhibitory functions. Gardeniae Fructus(GF) is a Heat-clearing herb used in traditional Korean medicine, and a wide range of studies on its antiinflammatory effects are being carried out. The authors investigated the effect that Gardeniae Fructus has on regulatory T cells. Methods : The authors screened 14 herbs for their effects on regulatory T cells. 100mg of each herb were separately dissolved in 1ml of sterile saline and the supernatant was harvested after 10 minutes of centrifuge at 15,000 rpm. The supernatant was filtered through a 0.2 ${\mu}m$ syringe filter, and the resulting stock was refrigerated at $4^{\circ}C$. The stock was diluted before testing and used at a final concentration of $0.01{\mu}g/ml$. CD4+CD25+ T cells from healthy BALB/c spleens were used as natural regulatory T cells (nTreg), and CD4+CD25- T cells were used as reactive T cells. CD4+CD25+ and CD4+CD25- T cells were activated with anti-CD3e ($10{\mu}g/m{\ell}$)/anti-CD28 ($1{\mu}g/m{\ell}$) and cultured. IL-10 from supernatant of the culture medium was measured by IL-10 cytokine ELISA. The percentages, cell numbers, phenotype and function of CD4+CD25+ Treg cells were determined by flow cytometry. Results : Gardeniae Fructus was shown to be the most potent herb among the 14 herbs tested for suppressing CD4+CD25- reactive T cell proliferation by stimulating CD4+CD25+ natural regulatory T cells. Gardeniae Fructus induces IL-10 secretion increase by stimulating CD4+CD25+ natural regulatory T cells, and indirectly suppresses CD4+CD25- reactive T cell proliferation through increasing CD25 (IL-2 receptor $\alpha$) expression and thus promoting bonding with IL-2. Gardeniae Fructus did not directly affect CD4+CD25- reactive T cell proliferation. Conclusions : Gardeniae Fructus suppressed reactive T cell proliferation through inducing increases in IL-10 secretion and CD25 (IL-2 receptor $\alpha$) expression.
Kwon, Eun Hee;Lee, Eun Min;Kim, Min Yong;Chang, Heyn Sung;Guahk, Young Tae;Kim, Kwang Ho;Nho, Nam Sun
Applied Chemistry for Engineering
/
v.25
no.2
/
pp.209-214
/
2014
In this paper, the rheological behaviors and non-Newtonian characteristics of maltenes which is effected by hydrocarbon solvent type, solvent mixing ratio, temperature and shear rate was measured and compared with oil sands bitumen. Maltenes was made by SDA (solvent deasphalting) method from oil sands bitumen. Oil sands bitumen had apparent viscosities of $800{\sim}150000mPa{\cdot}s$ measured at a shear rate of $50sec^{-1}$ in the range of $25{\sim}85^{\circ}C$ and showed yield stress of 0.1~0.3 Pa at the temperatures below $35^{\circ}C$. All the oil sands bitumen and maltenes exhibited a shear-thinning, i.e. pseudoplastic behavior and apparent viscosity of maltenes decreased with decreasing carbon numbers of hydrocarbon solvent. The change in apparent viscosity with temperature could be described by the simple Guzman-Andrade equation, and maltene viscosities were decreased as the mixing ratio of n-pentane was raised. Also, all maltenes approached to Newtonian fluid as temperature were increased. the degree of pseudoplasticity was enhanced with decreasing carbon number of solvent.
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.