• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.3
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• pp.1-6
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• 2010

A new testing method named pitch deposit tester (PDT) was developed by KRICT in order to evaluate the deposit potential of micro-stickies. The new method involves depositing the potential pitch particles on the air bubble covered plastic film set in the pitch deposit tester (PDT) and analysing the deposited area by an image analyzer. In this study, the effect of fixing agents on potential pitch deposition was elucidated. The effects of some fixing agents (polyamine and polyethyleneimine) on pitch control were investigated by the PDT test of 100% recycled newsprint stock. The study suggested that proper use of the PEI can lead to better pitch control than that of polyamine. The efficiency of novel screening method using the PDT and retention and drainage analyser (RDA) for fixing agents in terms of retention and deposit contamination could be confirmed by above mentioned results.

• Environmental Analysis Health and Toxicology
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• v.30 no.sup
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• pp.4.1-4.7
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• 2015

Objectives Approximately 2000 phase-in substances are subject to registration according to the Act on the Registration and Evaluation, etc. of Chemical Substances (K-REACH), and the expected testing cost is 2.06 trillion Korean won assuming all the test data required for registration are acquired. The extent to which these enormous test costs can be reduced depends on the availability of existing data that can be used to meet the requirements of the K-REACH we examined the current availability of test data that can be used for chemical substance registration. Methods We analyzed the possibility of utilizing the existing test data obtained from 16 reference databases for 369 of 518 kinds of phase-in substances subject to registration that were reported in last October 2014. Results The physical and chemical properties were available for 57.1% of substances, whereas data regarding human hazards and environmental hazards were available at considerably lower rates, 8.5% and 11.8%, respectively. Conclusions Physical and chemical properties were available for a fairly high proportion, whereas human hazards and environmental hazards were reported for considerably fewer substances.

• Proceedings of the Korean Reliability Society Conference
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• 2006.05a
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• pp.48-54
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• 2006

In this thesis, accelerated life test (ALT) method and procedure for rubber O-ring are applied to assure specified reliability of the products at guaranteeing the life of the products. Rubber O-ring is parts that keep intensity or make machine operation smoothly on attrition portion of machine and is used to prevent that oil is leaked. Usually. Rubber O-ring used NBR that is copolymer of acrylonitrile and butadiene. this are superior oil resistance, heat resistance, durability of abrasion, cold resistance, chemical resistance etc. The accelerated life test model for rubber O-ring are developed using the relationship between stresses and life characteristics of products. Using the accelerated life test method and the acceleration life test equipment which is developed, we performed life test, collected life data and analyzed the results of tests. The proposed accelerated life test method and procedure may be extended and applied to testing similar kinds of products to reduce test times and costs of the tests remarkably.

• Journal of the Korean Chemical Society
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• v.57 no.1
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• pp.40-51
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• 2013

In order to develop a quantitation method for Perfluorooctanesulfonic acid(PFOS) contained in plastics that are mainly used in electric and electronic equipment, this study consisted of conducting method validations with LDPE samples using soxhlet solvent extraction and LC/MS. As a result, the limits of detection and quantitation (LOD, LOQ) were $2.58{\mu}g/L$ and $7.82{\mu}g/L$, respectively. Additionally, the recovery was 96-102%. For the correlation coefficient of LC/MS, the $r^2$ value was 0.9992 in the concentration range of $7.82-100{\mu}g/L$, which confirmed its linearity. Furthermore, for the standardization of the analysis method for PFOS in electric and electronic equipment to correspond to EU environmental regulations, we conducted a proficiency test with a number of domestic and international testing laboratories. Three of the ten testing laboratories that participated in the proficiency test submitted outliers. Accordingly, we examined the cause of the outliers using the $^{19}F$ NMR, finding that the main cause was an error in the processing of the results for isomers in PFOS that existed in standard solutions and samples.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.8
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• pp.1010-1020
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• 2014

Ballast water effluent treated by an electrolytic method contains reactive chlorine species and disinfection by-products (DBPs). In this study, we conducted whole effluent toxicity (WET) testing and ecological risk assessment (ERA) to investigate its ecotoxicological effects on marine environment. WET testing was carried out for three marine pelagic organisms, i.e., diatom Skeletonema costatum, rotifer Brachionus plicatilis and fish Paralichthys olivaceus. The biological toxicity test revealed that S. costatum was the only organism that showed apparent toxicity to the effluent; it showed no observed effect concentration (NOEC), lowest observable effect concentration (LOEC) and effect concentration of 50% (EC50) values of 12.5%, 25.0% and 83.3%, respectively, at brackish water condition. In contrast, it showed insignificant toxicity at seawater condition. B. plicatilis and P. olivaceus also showed no toxicities to the effluent at the both salinity conditions. Meanwhile, chemical analysis revealed that the ballast water effluent contained total residual oxidants (TROs) below $0.03{\mu}g/L$ and a total of 20 DBPs including bromate, volatile halogenated organic compounds (VOCs), halogenated acetonitriles (HANs), halogenated acetic acids (HAAs) and chloropicrin. Based on ERA, the 20 DBPs were not considered to have persistency, bioaccumulation and toxicity (PBT) properties. Except monobromoacetic acid, the ratio of predicted environmental concentration (PEC) to predicted no effect concentration (PNEC) of the other 19 DBPs did not exceed 1. Thus, our results of WET testing and ERA indicated that the ballast water effluent treated by electrolysis and subsequently neutralization was considered to have no adverse impacts on marine environment.

• Journal of the Korean Society for Nondestructive Testing
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• v.31 no.5
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• pp.552-559
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• 2011

Recently, the eddy current testing(ECT), alternating current field testing, magnetic flux leakage testing and remote field testing have been used as a nondestructive evaluation method based on the electromagnetic induction phenomenon. The eddy current testing is now widely accepted as a NDE method for the heat exchanger tube in the electric power industry, chemical, shipbuilding, and military. The ECT system mainly consists of the synthesizer module, analog module, analog-to-digital converter, power supplier, and data acquisition and analysis program. In the previous study, the synthesizer module and the analog module which is essential to the ECT system were primarily developed, and in this study the data acquisition and analysis program were developed. The operation system for this program is based on the Windows 7, and optimized for the Korean users, and the specific feature of this program using setup wizard enables inspector to make a setup easily for acquisition and analysis of ECT data. In this paper, the configuration and functions of eddy current data acquisition and analysis program will be introduced.

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.2
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• pp.155-161
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• 2010

Recently, the electromagnetic techniques of the eddy current testing(ECT), alternating current field testing, magnetic flux leakage testing and remote field testing have been used as a nondestructive evaluation method based on the electromagnetic induction. The eddy current testing is now widely accepted as a NDE method for the heat exchanger tube in the electric power industry, chemical, shipbuilding, and military. The ECT system mainly consists of the synthesizer module, analog module, analog-to-digital converter, power supplier, and data acquisition and analysis program. In this study, the synthesizer module and the analog module which are essential to the ECT system were primarily developed. The developed ECT system is basically a multifrequency type which is able to inject the maximum four frequencies based on the frequency and time domain multiplexing method. Conclusively, we confirmed that the EC signal was processed appropriately in each circuit modules, and the Lissajous EC signal was displayed in the impedance plane.

• Journal of Environmental Science International
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• v.2 no.3
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• pp.201-206
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• 1993

The concentration of Total Suspended Particulates(T.S.P), size distribution of suspended particulates, and soluble anions of T.S.P in atmosphere of industrial region in Busan were investigated. T.S.P was measured by High-Volume Air Sampler and particle size distribution was measured by Anderson Air Sampler. We analyzed the chemical component of the T.S.P by ion Chromatography and measure4 the shape and size of T.S.P by Scanning Electron Micrography The small size of T.S.P mainly exist in industrial region, but the large size of T.S.P mainly exist in residentail area.

• Textile Coloration and Finishing
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• v.22 no.4
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• pp.300-305
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• 2010

Poly(ethylene terephthalate)(PET) tire cord has relatively lower adhesion properties caused by limited reacting sites. In order to improve the adhesion force between PET tire cord and rubber, an additional process to activate surface of PET has been employed. Atmospheric plasma was used to substitute the chemical finishing process of PET tire cord as a green dipping process. Contact angle was measured to confirm surface change of PET after plasma treatment. The treated PET tire cords with/without resorcinol-formaldehyde-latex(RFL) and unvulcanized rubber were vulcanized in a testing mold at $160^{\circ}C$. After atmospheric plasma treatment of PET tire cord, adhesion force was somewhat increased under some conditions.

• The Plant Pathology Journal
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• v.26 no.2
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• pp.198-202
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• 2010

A study was conducted to find out the relationship of physico-chemical properties (viz. organic carbon(OC), pH, electrical conductivity, nitrogen, phosphorus and potassium content) of ginger growing soil with incidence percentage of rhizome rot and wilt disease complex of ginger. Organic carbon content and pH of the ginger soil contributed significantly (93%) in the prediction of ginger rhizome rot and wilt disease complex incidence with negative correlation. Soil having weak acidic reaction with OC percent greater than 2.25 was observed to have the lower average incidence of the disease.