• Resources Recycling
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• v.10 no.6
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• pp.35-42
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• 2001

A study was conducted in order to remove Poly vinyl chloride (PVC) from granular plastic mixture by using Air Table. The motion of plastic particle on Air Table was investigated, and separation test on the plastic mixture with the mixing ratio of PVC 10% and PE 90% was conducted. At the optimum condition obtained from this study, that is frequency of 9.2Hz, air velocity of 1.05 m/sec, End-slope of $7.5 ^{\circ}$, Side-slope of $1^{\circ}$, Feeding speed of 450 g/min, etc., we could separate the PE-PVC mixture to PE (99.96% grade and 98.9% yield) and PVC (88.7% grade and 99.6% yield).

• Food Science and Preservation
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• v.10 no.3
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• pp.406-410
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• 2003

For selection of lactic acid bacteria for probiotics, we have examined isolated strains from Korean Dongchimi to assess the acid, bile, and pancreatic tolerance and the growth inhibition on the pathogens. Especially, a kind of isolated strains, FF-3 showed the highest resistancy to both of HCl and bile salt, as well as the highest inhibitory activities against Salmonella sp. and Escherichia coli. Further the bacteriocin of FF-3 showed relatively wide range of inhibition spectrum against gram positive and some gram negative bacterias. By using 16s rDNA sequencing method, FF-3 of the selected lactic acid bacteria were found to be identified as genus Lactobacillus.

• Journal of Sericultural and Entomological Science
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• v.38 no.1
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• pp.19-24
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• 1996

To investigate the genes which is related to immune reaction of Bombyx mori, differential screening was carried out using naive and induced B. mori mRNA probe. To begin with, we constructed the cDNA library with mRNA isolated from fifth instar larvae injected with E. coli(4 X 106 cells/larva) using Uni ZAP XR vector kit. Thirty-two inducible cDNAs showing higher intensity on the induced mRNA probing membranes were selected. Partial nucleotide sequences of 29 clones were determined and their expessed sequence tags (ESTs) were produced. Nineteen ESTs in 29 ESTs were matched in GenBank database and the rest of them were found to be unknown. These unmatched ESTs were presumed to be novel genes. The nineteen ESTs contained variable genes related to biological process in Bombyx mori and four classes immune genes. Four clones, BmInc 6, 8, 18 and 27 were similar to two antibacterial peptide genes, hemolin gene and transferrin gene, respectively.

• The Korean Journal of Mycology
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• v.42 no.4
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• pp.333-340
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• 2014

The aim of this study was to isolate a potential multifunctional biocontrol agent from bacteria for control of multiple plant diseases as an alternative to fungicides. A total of 201 strains were isolated from soil undamaged by repeated cultivation in Sunchang and their ability to produce antibiotics, siderophores and extracellular enzymes such as protease, cellulase and amylase was investigated. Selected strain SCS3 produced cellulose, protease and amylase. This strain also produced siderophores and showed excellent antifungal activity against various phytopathogens. SCS3 was identified as Bacillus subtilis using 16S rRNA sequencing, and named Bacillus subtilis SCS3. Finally, physiological and biochemical characteristics of B. subtilis SCS3 were examined. From the results, B. subtilis SCS3 was found to be a useful multifunctional biocontrol agent against various phytopathogens.

• Resources Recycling
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• v.17 no.6
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• pp.43-49
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• 2008

In this study, a scrap sorting system using a color recognition method has been developed to automatically sort out specified materials from a mixture, and its application as been examined in the separation of Cu and other non-ferrous metal parts from a mixture of iron scraps. The system is composed of three parts; measuring, conveying and ejecting parts. The color of scrap surface is recognized by the measuring part consisting of a line-scan camera, light sources and a frame grabber. The recognition is program-controlled by a image processing algorithms, and thus only the scrap part of designated color is separated by the use of air nozzles. In addition, the light system is designed to meet a high speed of sorting process with a frequency-variable inverter and the air nozzled ejectors are to be operated by an I/O interface communication with a hardware controller. In the functional tests of the system, its efficiency in the recognition of Cu scraps from its mixture with Fe ones reaches to more than 90%, and that in the separation more than 80% at a conveying speed of 25 m/min. Therefore, it is expected that the system can be commercialized in the industry of shredder makers if a high efficiency ejecting system is realized.

• KSBB Journal
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• v.21 no.2
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• pp.85-89
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• 2006

Typical property of the white-rot fungi is their ability to degrade lignin and other aromatic compounds with non-specific extracellular enzyme. In this work, the modification of the strain(Funalia trogii ATCC 200800) and the culture condition was performed to enhance enzyme productivity. Single cell was separated by the protoplasts formation and several putative laccase and manganese peroxidase inducers were tested. By adopting the modified strain, enzyme productivity increased comparing with that of the original strain. Extracellular enzyme formation was highly stimulated by the addition of copper and various aromatic compounds in the glucose-based culture medium.

• Journal of Embryo Transfer
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• v.22 no.3
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• pp.173-178
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• 2007

돼지 정자의 성 선별에는 일반적으로 유속 세포 분석기를 이용한다. 유속 세포 분석은 DNA량의 차이에 기초하여 정자를 분리하는 기술로써 X 정자와 Y 정자를 90% 정확도로 분리할 수 있다. 그러나 이러한 유속 세포분석 기술은 정자의 손상을 야기해 정자의 기능과 수정능에 영향을 미치므로, 본 연구에서는 특정한 핵산 서열을 탐지할 수 있는 Chromogenic in situ hybridization(CISH)을 그와 비교하여 평가하였다. 유속 세포 분석을 수행하기 위해 정자를 SYBR 14와 PI로 염색하였고, histogram, dotplot, density, contour를 측정하였다. Y 염색체 특이적인 primer를 이용한 PCR로 유속 세포 분석의 정확도를 검사하였다. HRP/DAB 시스템에 기초한 CISH 분석에는 X 또는 Y 염색체에 상보적으로 결합하는 probe가 사용되었다. CISH 분석은 기존의 방법들보다 빠르고 쉬우며 비용이 적게 든다는 장점이 있다. 또한, CISH는 보다 정화한 정자의 선별을 가능하게 하는 것으로 나타났다. 본 연구에 따르면 CISH가 기존의 선별 방법들을 평가하는 기술로서만이 아니라 특정한 성별을 가진 포유동물의 생산에도 사용될 수 있을 것이다.

• Resources Recycling
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• v.29 no.6
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• pp.15-26
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• 2020

In recent years, there is an increasing interest in environmental friendly treatment of waste-plastics in terms of the generation of microplastics. Accordingly, the recycling of waste-plastics is very important because it provides advantages of volume reduction, mitigation of carbon dioxide emission, and reproduction of value-added products. In particular, in order to recycle the eco-friendly waste-plastics, it is necessary to use a physical separation methods, and among them, flotation separation, which can separate material (i.e., polymer component) in waste-plastics is well known as a very effective separation method in terms of material recycle. Therefore, in this review, the research trend of flotation separation for effective separation of mixture waste-plastics was investigated. In addition, through the reported research results, approaches to use as new functional materials from polymers, which are raw materials for waste-plastics, are summarized.

• Korean Journal of Microbiology
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• v.37 no.3
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• pp.189-196
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• 2001

Eighty-seven microbial strains capable of growing on bisphenol A (BPA) as a sole carbon source were isolated from soils, waste waters and sludges. Among them, three bacterial strains were finally selected as potential decomposers through measuring BPA-degradation efficiency by HPLC analysis. Two of these bacterial strains were identified as Serratia marcescens 1901 and S. marcescens 1902, and another was Pseudomonas putida 1401 by 16S rDNA partial sequences and based on morphological and physiological properties. They showed higher cell growth and BPA degradation in PAV (PAS medium containing vitamin mixtures) than in PAS medium. The degradation efficiencies of these bacterial strains were within a range of 20-40% in the PAV containing 500 mg/1 or 100 mg/l of BPA fur 3 days. S. marcescens 1901 showed higher degradation efficiency at 100 mg/1 of BPA than those of other selected strains, while S. marcescens 1902 and P. putida 1401 degraded a high concentration of BPA (500 mg/l) with a degradation efficiency of 40% for 3 days. The BPA degradation using a mixed culture of three selected strains showed the similar level of dog-radation efficiency with that using a pure culture.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.5
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• pp.571-577
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• 2012

In this study, a small movable batch treatment system for dredging soil deposited in a rain water tube is proposed; further, a vacuum silo sorting separation device with a vacuum silo, first-stage sorting separator, and conveyor is designed. The vacuum silo sorting separation device also consists of a storage tank, transferring screw, vacuum gate, screen bar, screen bar cleaner, and vacuum discharging device. In view of the fact that the flow of drawn air in the storage tank is a major factor influencing the sorting separation performance, the optimum shape of the tank is determined by CFD flow analysis. In addition, by using CAE structure analysis, the safety of a storage tank made of boards is examined. The specifications of the vacuum silo sorting separation device are determined by conducting mechanical and dynamic simulations of the driving mechanism of the vacuum silo sorting separation device through 3D-CAD modeling. Following this study, we will design a drum-screen-type second sorter, a decanter-type dehydration device, and waste water tank and pump as a secondary device. Further, on the basis of this design, we will construct a prototype model and carry out a field test.