• Title/Summary/Keyword: initial permeability

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New-Onset Malignant Pleural Effusion after Abscess Formation of a Subcarinal Lymph Node Associated with Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration

  • Jang, Sun Mi;Kim, Min Ji;Cho, Jeong Su;Lee, Geewon;Kim, Ahrong;Kim, Jeong Mi;Park, Chul Hong;Park, Jong Man;Song, Byeong Gu;Eom, Jung Seop
    • Tuberculosis and Respiratory Diseases
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    • v.77 no.4
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    • pp.188-192
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    • 2014
  • We present a case of an unusual infectious complication of a ruptured mediastinal abscess after endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), which led to malignant pleural effusion in a patient with stage IIIA non-small-cell lung cancer. EBUS-TBNA was performed in a 48-year-old previously healthy male, and a mediastinal abscess developed at 4 days post-procedure. Video-assisted thoracoscopic surgery was performed for debridement and drainage, and the intraoperative findings revealed a large volume pleural effusion that was not detected on the initial radiographic evaluation. Malignant cells were unexpectedly detected in the aspirated pleural fluid, which was possibly due to increased pleural permeability and transport of malignant cells originating in a ruptured subcarinal lymph node from the mediastinum to the pleural space. Hence, the patient was confirmed to have squamous cell lung carcinoma with malignant pleural effusion and his TNM staging was changed from stage IIIA to IV.

The Effects of High Pressure Water Contact State on Hydraulic Fracturing (고압수 접촉상태가 수압파쇄에 미치는 영향)

  • Lee, Sang Hun;Lim, Jong Se;Jang, Won Yil
    • Tunnel and Underground Space
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    • v.26 no.5
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    • pp.409-417
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    • 2016
  • The shale gas is emerging as one of the oil and gas resources which can replace the traditional oil and gas resources. As the shale layer where the shale gas is deposited has low permeability, the hydrofracturing method is required to improve the productivity. This study is designed to conduct the laboratory hydrofracturing test on the samples which are modeled after the drilling hole having the general drilling hole and spiral groove. And compare the initial fracturing pressure and fluid contact between them in order to the result of the hydrofracturing depending on the shape of the drilling hole. In addition, the results were compared with the numerical modeling values from 3DEC and they were also compared with the data from the advance researches. It was found from the study that rather than the contact area of the high pressures water, the force concentration depending on the form of guide hole was more effective in the hydrofracturing.

Characterization of the Hepatic Uptake of l-Anilino-8-naphthalene sulfonate(ANS) by Isolated Rat Hepatocytes-Is Serum Protein Essential for Hepatic Uptake of ANS in the Liver?- (유리간세포를 사용한 ANS의 간내 이행에 관한 연구-ANS의 간내 이행과정에 단백질 매개 기구가 존재하는가?-)

  • Chung, Youn-Bok;Yuk, Dong-Yeon;Han, Kun
    • Journal of Pharmaceutical Investigation
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    • v.21 no.1
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    • pp.43-50
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    • 1991
  • The hepatic uptake of an anionic fluorescence probe, l-anilino-8-naphthalene sulfonate (ANS) was characterized using isolated rat hepatocytes. The initial uptake rate of ANS by isolated hepatocytes was determined. The uptake process of ANS was fitted well to the Michaelis-Menten equation with a saturable component. The $V_{max}$ and $K_m$ values were $2.9{\pm}0.1\;nmol/min/mg$ protein and $29.1{\pm}3.2\;{\mu}M$, respectively. The uptake clearance $(CL_{up})$ based on the ratio of $V_{max}$ to $K_m$ was 11.7 ml/min/g liver, revealing the good coincidence with that assessed from the analysis of the plasma disappearance curve in previous report. Furthermore, the effect of serum protein on the hepatic uptake of ANS into isolated hepatocytes was investigated. The permeability clearances $(PS_{inf})$ of ANS uptake were much higher than those predicted based on the unbound fractions in the presence of serum. These suggested that the hepatic uptake of extensively serum protein-bound ANS is mediated not only by the unbound form of ligand but also by the serum protein-mediated uptake mechanism.

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Performance of membrane filtration in the removal of iron and manganese from Malaysia's groundwater

  • Kasim, Norherdawati;Mohammad, Abdul Wahab;Abdullah, Siti Rozaimah Sheikh
    • Membrane and Water Treatment
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    • v.7 no.4
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    • pp.277-296
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    • 2016
  • The aim of this research was to investigate the ability of nanofiltration (NF) and ultrafiltration (UF) membranes as a filtration unit for groundwater treatment for drinking water resources. Commercial membranes denoted as TS40, TFC-SR3 and GHSP were used to study the performance based on rejections and fluxes. The investigation has been conducted using natural groundwater obtained from a deep tube well with initial concentration of iron (Fe) and manganese (Mn) at 7.15 mg/L and 0.87 mg/L, respectively. Experimental results showed that NF membranes exhibited higher fluxes than UF membrane with pure water permeability at 4.68, 3.99 and $3.15L.m^{-2}.h^{-1}.bar^{-1}$, respectively. For metal rejection, these membranes have performed higher removal on Fe with TS40, TFC-SR3 and GHSP membranes having more than 82%, 92% and 86% respectively. Whereas, removal on Mn only achieved up to 60%, 80% and 30%, for TS40, TFC-SR3 and GHSP membranes respectively. In order to achieve drinking water standard, the membranes were efficient in removing Fe ion at 1 and 2 bar in contrast with Mn ion at 4 and 5 bar. Higher rejection of Fe and Mn were achieved when pH of feed solution was increased to more than 7 as TFC-SR3 membrane was negatively charged in basic solution. This effect could be attributed to the electrostatic effect interaction between membrane material and rejected ions. In conclusion, this study proved that NF membrane especially the TFC-SR3 membrane successfully treated local groundwater sources for public drinking water supply in line with the WHO standard.

Perforation optimization of hydraulic fracturing of oil and gas well

  • Zhu, Hai Yan;Deng, Jin Gen;Chen, Zi Jian;An, Feng Chen;Liu, Shu Jie;Peng, Cheng Yong;Wen, Min;Dong, Guang
    • Geomechanics and Engineering
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    • v.5 no.5
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    • pp.463-483
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    • 2013
  • Considering the influences of fluid penetration, casing, excavation processes of wellbore and perforation tunnels, the seepage-deformation finite element model of oil and gas well coupled with perforating technique is established using the tensile strength failure criterion, in which the user-defined subroutine is developed to investigate the dynamic evolvement of the reservoir porosity and permeability. The results show that the increases of perforation angle and decreases of perforation density lead to a higher fracture initiation pressure, while the changes of the perforation diameter and length have no evident influences on the fracture initiation pressure. As for initiation location for the fracture in wellbore, it is on the wellbore face while considering the presence of the casing. By contrast, the fractures firstly initiate on the root of the tunnels without considering casing. Besides, the initial fracture position is also related with the perforation angle. The fracture initiation position is located in the point far away from the wellbore face, when the perforation angle is around $30^{\circ}$; however, when the perforation angle is increased to $45^{\circ}$, a plane fracture is initiated from the wellbore face in the maximum horizontal stress direction; no fractures was found around perforation tunnels, when the angel is close to $90^{\circ}$. The results have been successfully applied in an oilfield, with the error of only 1.1% comparing the fracture initiation pressure simulated with the one from on-site experiment.

Infiltration behaviour of the slurry into tunnel face during slurry shield tunnelling in sandy soil (사질성 지반에서 이수식 쉴드 TBM 적용시 굴진면으로의 이수 침투특성에 대한 해석적 고찰)

  • Roh, Byoung-Kuk;Koh, Sung-Yil;Choo, Seok-Yeon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.14 no.3
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    • pp.261-275
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    • 2012
  • This paper presents numerical analysis of the mud cake infiltration behaviour which is influenced tunnel face stability during excavation by slurry shield TBM. This analysis method can make useful data to select proper shield TBM type and to set up the construction plan. But effective analysis did not proposed until now. In this paper, we carried out numerical analysis using by $PFC^{2D}$ fluid coupling simulation which is suitable for sandy soil modelling. As a analysis result, we checked that the slurry infiltration behaviour varied with soil permeability and slurry characteristic(specific weight, viscosity etc). This analysis method is helpful safety excavation through anticipating the proper slurry viscosity at the design stage and verifying the slurry quality at initial excavation stage.

The stability of tear film for Korean (한국인에 대한 누액 안정성 조사)

  • Lee, Seong-Wook;Sim, Hyun-Seog;Jang, Seong-Joo
    • Journal of Korean Ophthalmic Optics Society
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    • v.6 no.2
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    • pp.161-164
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    • 2001
  • The purpose of our study was stability of tear film for Korean. In the 1970s, the major problem for the contact lens practitioner was the management of contact lens parameters. In the 1980s, oxygen permeability was the main problem in contact lens practice: now it is dry eyes. To appropriately fit the patient with contact lenses it is imperative to know in advance if the patient has a marginal dry eye. Based on the initial diagnosis appropriate care can be taken to minimize problems with the result that the patient can successfully wear contact lenses. A well known test for dry eyes is Schirmer test which has shown to be useful for diagnosing Sjogren syndrome. Biomicroscopy can often unmask numerous problems. The classical test for marginal dry eye is measuring the tear break up time(TBUT). A dry eye problem with contact lenses is often caused by the lid. If an incomplete blink is responsible for the dry eye it is possible to change the situation by blinking exercises. The result of these test, mean value of age was 22.8, mean value of blink rate was 19 times/min, mean value of Schirmer test was 25 mm/5 min, mean value of TBUT was 7.1 sec.

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The Power Loss Characteristics of Mn-Zn Ferrites at MHz Region with Sintering Condition (소성조건에 따른 MHz 대역의 Mn-Zn ferrite 전력손실 특성)

  • Suh J.J.;Song B.M
    • Resources Recycling
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    • v.12 no.6
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    • pp.26-31
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    • 2003
  • The power loss characteristics of Mn-Zn ferrite were observed with the sintering temperature. In case of $1150 ^{\circ}C$ sintering, the core loss increased with measuring temperature, and does not have minimum value at the point where the magnetocrystalline anisotropy be 'zero'. This reason mainly due to the change of core loss mechanism with grain size which affects residual loss. The grain size and sintered density slightly increased with equilibrium oxygen partial pressure at$ 1150 ^{\circ}C$ sintering. The resistivity and initial permeability showed no significance with atmosphere, these results due to complex effect of $Fe^{2+}$ concentration and microstructure change. The core loss at $100^{\circ}C$ decreased as the equilibrium oxygen partial pressure increased.e increased.

Use of a Combined Photocatalysis/Microfiltration System for Natural Organic Matter Removal (광촉매 반응과 침지형 정밀여과를 이용한 자연산 유기물의 제거)

  • 추광호;박경원;김문현
    • Membrane Journal
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    • v.14 no.2
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    • pp.149-156
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    • 2004
  • This work focused on the degradation of natural organic matter (NOM) present in lake water using a combined pkotocatalysisimicrofiltration (MF) process. The system performances were investigated in terms of organic removal efficiency and membrane permeability. The addition of iron oxide particles (IOP) into the photocatalytic membrane reactor improved initial NOM removal by sorption, but during photocatalysis the removal efficiency was reversed, probably due to the scattering of UV light by IOP. The modification of TiO$_2$ surfaces by IOP deposition was conducted to enhance the photocatalytic NOM removal efficiency. A minimal amount of Impregnation of IOP on TiO$_2$ surfaces was required to prevent the light scattering effect as well. The coating of MF membranes with IOP helped to improve the NOM removal efficiency while sorbing NOM by IOP. Regardless of tile operating conditions and particles addition examined, no significant fouling was occurring at a flux of 15 L/$m^2$-h during entire MF operation.

Effect of Extreme Rainfall on Cut Slope Stability: Case Study in Yen Bai City, Viet Nam

  • Tran, The Viet;Trinh, Minh Thu;Lee, Giha;Oh, Sewook;Nguyen, Thi Hai Van
    • Journal of the Korean GEO-environmental Society
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    • v.16 no.4
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    • pp.23-32
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    • 2015
  • This paper addresses the effects of extreme rainfall on the stability of cut slopes in Yen Bai city, Northern Viet Nam. In this area, natural slopes are excavated to create places for infrastructures and buildings. Cut slopes are usually made without proper site investigations; the design is mostly based on experience. In recent years, many slope failures have occurred along these cuts especially in rainy seasons, resulting in properties damaged and loss of lives. To explain the reason that slope failure often happens during rainy seasons, this research analyzed the influence of extreme rainfalls, initial ground conditions, and soil permeability on the changes of pore water pressure within the typical slope, thereafter determining the impact of these changes on the slope stability factor of safety. The extreme rainfalls were selected based on all of the rainfalls triggering landslide events that have occurred over the period from 1960 to 2009. The factor of safety (FS) was calculated using Bishop's simplified method. The results show that when the maximum infiltration capacity of the slope top soil is less than the rainfall intensity, slope failures may occur 14 hours after the rain starts. And when this happens, the rainfall duration is the deciding factor that affects the slope FS values. In short, cut slopes in Yen Bai may be stable in normal conditions after the excavation, but under the influence of tropical rain storms, their stability is always questionable.