• Title/Summary/Keyword: Filtration barrier

Search Result 23, Processing Time 0.02 seconds

Inactivation of Ralstonia Solanacearum using Filtration-Plasma Process (여과-Plasma 공정을 이용한 Ralstonia Solanacearum 불활성화)

  • Kim, Dong-Seog;Park, Young-Seek
    • Journal of Environmental Science International
    • /
    • v.23 no.6
    • /
    • pp.1165-1173
    • /
    • 2014
  • For the field application of dielectric barrier discharge plasma reactor in nutrient solution culture, a filtration-DBD (dielectric barrier discharge) plasma reactor was investigated for the Ralstonia solanacearum which causes bacterial wilt in aquiculture. The filtration-DBD plasma reactor system of this study was consisted of filter, plasma reactor, reservoir. The DBD plasma reactor consisted of a quartz dielectric tube, discharge electrode (inner) and ground electrode (outer). The experimental results showed that the inactivation of R. solanacearum with filter media type in filter reactor ranked in the following order: anthracite > fiber ball > sand > ceramic ball > quartz ceramic. In filtration + plasma process, disinfection effect with the voltage was found to small. In disinfection time of 120 minutes, residual R. solanacearum concentration was 1.17 log (15 CFU/mL). When the continuous disinfection time was 120 minute, disinfection effect was thought to keep the four days. In sporadic operation mode of 30 minutes disinfection - 24 hours break, residual R. solanacearum concentration after five days was 0.3 log (2 CFU/mL). It is considered that most of R. solanacearum has been inactivated substantially.

A study on nanoparticle filtration characteristics of multilayer meltblown depth filters

  • Lee, Kang-San;Hasolli, Naim;Jeon, Seong-Min;Lee, Jae-Rang;Kim, Kwang-Deuk;Park, Young-Ok;Hwang, Jungho
    • Particle and aerosol research
    • /
    • v.12 no.3
    • /
    • pp.51-56
    • /
    • 2016
  • Due to recent development in nanotechnology and increasing usage and production of nanomaterials, numerous studies related to environment, sanitation and safety handling of nanoparticle are being conducted. Since nanoparticles can be easily absorbed into human bodies through breathing process, based on their toxic substances and their large specific surface, these particles can cause serious health damage. Therefore, to reduce nanoparticle emissions, nanofiltration technology is becoming a serious issue. Filtration is a separation process during which a fluid passes through a barrier by removing the particles from the stream. Barrier filters can be made of various materials and shapes. One of the most common type of barrier filter is the fibrous filter. Fibrous filters are divided in two types: nonwoven and woven fabrics. Polypropylene is a thermoplastic material, used as a base material for melt blown nonwoven fabric. In this study, we examined filtration property of KCl nanoparticles with a mean particle diameter of 75 nm using multilayer meltblown filter samples. These experiments verify that the penetration of nanoparticle in the filter correlate with pressure drop; the meltblown layer MB1 has the greatest effect on dust collection efficiency of the filter. Among all tested samples, dust collection efficiency of 2-layer filter was best. However, when considering the overall pressure drop and dust collection efficiency, the 4-layer filter has the highest quality factor for particles smaller than 70 nm.

The Transmission Electron Microscopic Study on the Alteration of Filtration Barrier in Aged Rat Kidney (흰쥐 콩팥여과관문의 노화 변화에 관한 투과전자현미경적 연구)

  • Lee, Se-Jung;Lim, Hyoung-Soo;Lim, Do-Seon;Hwang, Douk-Ho
    • Applied Microscopy
    • /
    • v.38 no.2
    • /
    • pp.107-115
    • /
    • 2008
  • The filtration barrier of kidney consists of endothelial cell, glomerular capillary, glomerular basement membrane, mesangial matrix, and podocyte. In aged rats, the morphological changes were shown in various parts, including the glomerulus. These changes were thickening of basement membrane and mesangial matrix, crescent formation of glomerular capillary, deformity of foot processes, glomerular sclerosis and obsolescence. But these glomerular morphologies are partial images or few serial images analysis. In this study, we examined the morphological alteration of glomerulus in the young and aged rats by light microscopy, transmission electron microscopy and three dimensional reconstruction. We were found in aged rat glomerulus, expansion of urinary space and mesangial matrix, thickening and degrading of glomerular basement membrane, decreasing in podocyte foot processes, fragmentation of podocytic nucleus membrane. These observations indicate that may provide useful data for investigating the pathogenesis of age-related dysfunction of kidney.

A laboratory study on synthetic fiber filter for further treatment of turbid stormwater from construction sites

  • Yuan, Qingke;Kim, Youngchul
    • Membrane and Water Treatment
    • /
    • v.10 no.2
    • /
    • pp.105-112
    • /
    • 2019
  • On the purpose of conform the more stringent government regulation for turbid stormwater from construction sites, the feasibility and availability of synthetic fiber placing after the conventional protection barrier were tested in this study. Initially, comparative work on the filtering performance of fiber media and conventional gravel filter was carried out, 27% higher filtration capacity was obtained under the similar operational conditions. The filter efficiency was about 20 to 52% with a varying filter depth of 5 to 15cm, presuming at extreme storm flow conditions (800-1500 m/day of filtration rates). Fiber filter was found to have a similar filtration prosperity as grain media; namely, the separation efficiency is directly and inversely proportional to filter depth and rate, respectively. The effects of filter aid (polyaluminium chloride) on filter performance was also investigated, it greatly affected the turbidity reduction at the dosage of 2 mg/L. At the time of breakthrough, a simple filter washing was carried out, herein, the solid recovery achieved over than 88% and greatly determined by operational parameters. Based on the operational data, the empirical models aimed for predicting filtration efficiency were established, which can effectively determine the required filter depth and filtration area in field.

Evaluation of Extended Canine Semen after Different Filtration Treatment (개 희석 정액의 다양한 filtration 처리 후 정자평가)

  • Kim, Yong-Jun;Kim, Jin-Young;Kim, Sue-Hee;Lee, Young-Jun
    • Journal of Veterinary Clinics
    • /
    • v.24 no.4
    • /
    • pp.577-583
    • /
    • 2007
  • It is important to obtain semen with good quality for efficient fertilization and pregnancy. To obtain these semen, various methods have been developed but most of these methods are time consuming and require costly equipment. Therefore, the objective of this research is to investigate the usability of column filtration system as quick and simple method to get sperm with better quality. Ejaculates were obtained from 5 dogs and analyzed with basic quality parameters before each filtration. Sperm concentration was adjusted to $5{\times}10^7/ml$ after dilution. The experimental groups were divided into non-filtered group(control) and filtered groups(glass wool, Sephadex 5% and Sephadex 20%). Ejaculates were filtered through each filter system and assessed by recovery rate of sperm, motility, normal morphology, CFDA/PI stain and plasma membrane integrity(hypo-osmotic swelling test, HOST). The lowest recovery rate of spermatozoa was recorded in glass wool filtration group, followed by 20% Sephadex filtration group(p<0.05). There was no significant difference between control(non-filtered) and 5% Sephadex filtration poop. Also, there was no significant difference of sperm motility assessed under light microscope among experimental groups. Morphological normality of canine spermatozoa was the highest in the glass wool filtration group and the lowest in the 5% Sephadex filtration group with no significant differences versus 20% Sephadex filtration and control group, respectively(p<0.05). Viability of canine sperm assessed by CFCA/PI staining was the highest in the glass wool filtration poop with no significant difference versus the control group, and the lowest in the 20% Sephadex filtration group with no significant difference versus 5% Sephadex filtration group, respectively(p<0.05). HOS values of canine sperm was the highest in the 20% Sephadex filtration group with no significant difference versus 5% Sephadex filtration group, and the lowest in the control poop with no significant difference versus glass wool filtration group, respectively(p<0.05). Therefore, these results indicated that filtration treatment for extended canine sperm would be useful method to get sperm with better quality by trapping the damaged sperm, consequently filter would be physical barrier against injured or immotile sperm.

Air-Filter Media Characteristics of Wet-laid Nonwoven based on HDPE Plexi-filament (고밀도 폴리에틸렌 플렉시 필라멘트로 제조된 습식부직포의 에어필터 여재 특성 연구)

  • Bae, Younghwan;Wee, Jae-Hyung;Lee, Myungsung;Yeang, Byeong Jin;Kim, Dokun;Yeo, Sang Young
    • Textile Coloration and Finishing
    • /
    • v.33 no.4
    • /
    • pp.302-308
    • /
    • 2021
  • Air filters are being used in countless places from industrial sites to everyday life. The spread of the COVID-19 virus, which started in 2019, is disrupting people's daily lives, and the importance of air filters as a basic means to prevent the spread of these diseases is further highlighted. In this study, the purpose was to develop another type of air filter media with excellent barrier properties that can replace PP meltblown nonwoven fabrics widely used commercially due to its excellent electrostatic properties, differential pressure and filtration efficiency. Therefore, wet-laid nonwoven for air filters were manufactured using plexi-filaments formed through flash spinning and having various fiber diameter from hundreds of nanometers to tens of micrometers, and its applicability as an air-filter media was investigated compared to the meltblown nonwoven. As a result of the performance evaluation, it was found that the filtration efficiency and barrier performance at 0.3㎛ was superior to that of the meltblown nonwoven of the same weight, although the differential pressure was high due to morphological properties of the plexi-filament.

Genetic Basis of Steroid Resistant Nephrotic Syndrome

  • Park, Eujin
    • Childhood Kidney Diseases
    • /
    • v.23 no.2
    • /
    • pp.86-92
    • /
    • 2019
  • Steroid-resistant nephrotic syndrome (SRNS) has long been a challenge for clinicians due to its poor responsiveness to immunosuppressants, and rapid progression to end-stage renal disease. Identifying a monogenic cause for SRNS may lead to a better understanding of podocyte structure and function in the glomerular filtration barrier. This review focuses on genes associated with slit diaphragm, actin cytoskeleton, transcription factors, nucleus, glomerular basement membrane, mitochondria, and other proteins that affect podocyte biology.

Comparison of Environmental Evaluation for Paper and Plastic Based Mask Packaging (종이 기반과 플라스틱 기반 보건마스크 패키징의 환경영향 비교)

  • Dongho Kang;Youjin Go;Sanghoon Oh;Gohyun Choo;Jisoo Jang;Junhyuk Lee;Jinkie Shim
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
    • /
    • v.30 no.1
    • /
    • pp.73-83
    • /
    • 2024
  • In this study, environmental evaluation of high barrier coated paper (coating layer/paper) packaging is conducted in comparison with conventional aluminum laminated (PET/VMPET/LLDPE) plastic packaging. The target product for this packaging is a KF94 mask, which requires a high barrier of water and oxygen to maintain the filtration ability of the mask filter. The functional unit of this study is 10,000 mask packaging materials based on a material capable of blocking oxygen (<1 g/m2day) and moisture (<3 g/m2day) for the preservation of KF94 masks. In order to understand the results easily, paper-based mask packaging system divided into 6 stages (pulp, pulping & paper making, calendaring & coating, printing, packing and waste management), while plastic-based mask packaging consists of 5 stages (material production, processing, printing, packing, waste management) In case of paper-based mask packaging, most contributing stage is calendaring & coating, resulting from heat and electricity production. On the other hand, plastic-based mask packaging is contributed more than 30% by material production, specifically due to linear low density polyethylene and purified terephthalic acid production. The comparison results show that global warming potential of paper-based mask packaging has 32% lower than that of plastic-based mask packaging. Most of other impact indicators revealed in similar trend.

Application of a fouling resistant microfiltration membrane in activated sludge process (막오염 저항성이 우수한 정밀여과막의 생물학적 처리공정 적용)

  • Myoung, Su-Wan;Park, In-Hwan;Kim, In-Chul;Lee, Kew-Ho
    • Proceedings of the Membrane Society of Korea Conference
    • /
    • 2004.05b
    • /
    • pp.140-143
    • /
    • 2004
  • Membrane bioreactors (MBRs) used for water purification are based on the association of a bioreactor, within which a culture of microorganisms degrades the polluting compounds, and a membrane filtration separator. The use of a porous barrier usually ensures the disinfection of the effluent.(omitted)

  • PDF

High Glucose and Advanced Glycosylation Endproducts(AGE) Modulate the P-cadherin Expression in Glomerular Epithelial Cells(GEpC) (배양한 사구체 상피세포에서 고농도 당과 후기 당화합물에 의한 P-cadherin의 변화)

  • Ha Tae-Sun;Koo Hyun-Hoe;Lee Hae-Soo;Yoon Ok-Ja
    • Childhood Kidney Diseases
    • /
    • v.9 no.2
    • /
    • pp.119-127
    • /
    • 2005
  • Purpose : Podocytes are critical in maintaining the filtration barrier of the glomerulus and are dependent on the integrity of slit diaphragm(SD) proteins including nephrin, p-cadherin, and others. Diabetic proteinuric condition demonstrates defects in SD molecules as well as ultrastructural changes in podocytes. We examined the molecular basis for this alteration of SD molecules especially on P-cadherin as a candidate regulating the modulation of pathogenic changes in the barrier to protein filtration. Methods : To investigate whether high glucose and AGE induce changes in SD, we cultured rat GEpC under normal(5 mM) or high glucose(30 mM) and AGE- or BSA-added conditions and measured the change of P-cadherin expression by Western blotting and RT-PCR. Results : We found that administration of high glucose decreased the P-cadherin production significantly in the presence or absence of AGE by Western blotting. In RT-PCR high glucose with or without AGE also significantly decreased the expression of P-cadherin mRNA compared to those of controls. Such changes were not seen in the osmotic control. Conclusion : We suggest that high glucose with or without AGE suppresses the Production of P-cadherin at the transcriptional level and that these changes nay explain the functional changes of SD in diabetic conditions. (J Korean Soc Pediatr Nephrol 2005;9:119-127)

  • PDF