• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.111-120
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• 2006

Opening size of 3 types of geotextile were tested using dry and wet sieving methods to evaluate characteristics of test methods and to compare the test results. Judging from test results, dry sieving method is a poor test, having many problems causing many errors but a simple-quick test. Wet sieving method is a very specific test avoiding many of the problems of dry sieving such as electrostatic charges, trapping in the geotextiles and so on. However, one of wet sieving tests, KSK ISO12956, takes long time to complete a test and is too strict to handle loss of granular material. Generally, opening size of a geotextile by wet sieving test is smaller than that of dry sieving test. Especially, opening size by KSF 2126 which is one of wet sieving test but disused at present anymore is similar or smaller than that by KSK ISO12956 method.

• Journal of the Korean GEO-environmental Society
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• v.11 no.5
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• pp.15-23
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• 2010

Dry sieving, wet sieving and photoscattering analyzer were tested as particle size analyzing methods for sediments from rivers and lakes of Han river, Nakdong river, Youngsan river, and Kumgang river area. Dry sieving showed a big error due to coagulating effect over drying process and this phenomena was severe for lake sediment. Wet sieving and PSA showed an accurate results though wet sieving needs more labor and complicate processes. Freeze-dry or freeze-dry after oxidation of organics with hydrogen peroxide showed improved results but gave lower portion of fine particles in comparing with wet sieving. Heavy metal contents and extractable metal contents were investigated for the sediments and high heavy metal content and extractable amount were obtained from fine particles as expected. Using of proper particle size analyzing method is important and the sediment management should be focused on the fine particles.

• Journal of the Korean Society of Safety
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• v.34 no.3
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• pp.28-35
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• 2019

Dry water is a core-shell structured powder which comprises a very fine water core covered with hydrophobic silica particles. Recently, the dry water has attracted attention as a new type of fire extinguishing agents. However, characteristics of the dry water as a fire extinguishing agent have not been revealed until now. To our best knowledge, this is the first work to uncover effects of particle size of the dry water on the fire extinguishing performance. Pristine dry water, which has heterogeneous particle size distribution, was carefully separated by sieving method into three fractions which were a small size (ca. $110{\mu}m$) fraction, a medium size (ca. $220{\mu}m$) fraction and a large size (ca. $400{\mu}m$) fraction. Microscopic observations confirmed the effective separation of dry water's particle size. In extinguishing tests of wood cribs fire, the medium size dry water showed most excellent fire extinguishing performance, as compared to other dry waters having small (ca. $110{\mu}m$) and large (ca. $400{\mu}m$) particle size. The good performance of the medium size (ca. $220{\mu}m$) dry water may be attributed to the balance between cooling effect of the water core and smothering effect of the silica particles. It is also revealed that small size dry water has poor flowability than large size dry water.

• Journal of the Mineralogical Society of Korea
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• v.15 no.4
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• pp.283-291
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• 2002

Dry-based processes such as crushing, milling, sieving, magnetic and gravity separation were employed in order to investigate the purification characteristics of bentonite. The CECs of Gampo 13 and 35 bentonites were estimated at 88.3 and 93.3 meq/100 g and the samples contained quartz and feldspar as impurity minerals. According to the physical properties of constituent minerals of bentonite, the purification techniques were adopted to enhance the grade of montmorillonite High grade of montmorillonite could be obtained by the combination of each process. Consequently, the recovery of final products of Gampo 13 and 35 bentonite were 68.6 and 49.5%, and the CECs of them were 96.9 and 109.6 meq/100 g, respectively.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.252-256
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• 2001

The rapid development of communication equipment and information processing technology has led to a constant improvement in cordless communication. Lithium ion batteries used in cellular phones and laptop computers, in particular, have been in the forefront of the above revolution. These batteries use high value added raw materials and have a high and stable energy output and are increasingly coming into common use. The development of the material for the negative terminal has led to an improvement in the quality and efficiency of the batteries, whereas a reduction in the cost of the battery by researching new materials for the positive anode has become a research theme by itself. These long life batteries, it is being increasingly realized, can have value added to them by recycling. Research is increasingly being done on recycling the aluminum case and the load casing for the negative diode. This paper aims to introduce the current situation of recycling of lithium ion batteries. 1. Introduction 2. Various types of batteries and the situation of their recycling and the facts regarding recycling. 3. Example of cobalt recycling from waste Lithium ion secondary cell. 3-1) Flow Chart of Lithium ion battery recycling 3-2) Materials that make a lithium ion secondary cell. 3-3) Coarse grinding of Lithium ion secondary cell, and stabilization of current discharge 3-4) Burning 3-5) Grinding 3-6) Magnetic Separation 3-7) Dry sieving 3-8) Dry Classifying 3-9) Content Ratio of recycled cobalt parts 3-10) Summary of the Line used for the recovery of Cobalt from waste Lithium ion battery. 4. Conclusion.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3465-3474
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• 2014

Porous silica particles are the most prevailing raw material for stationary phases of liquid chromatography. During a long period of time, various methodologies for production of porous silica particles have been proposed, such as crashing and sieving of xerogel, traditional dry or wet process preparation of conventional spherical particles, preparation of hierarchical mesoporous particles by template-mediated pore formation, repeated formation of a thin layer of porous silica upon nonporous silica core (core-shell particles), and formation of specific silica monolith followed by grinding and calcination. Recent developments and applications of useful porous silica particles will be covered in this review. Discussion on sub-$3{\mu}m$ silica particles including nonporous silica particles, carbon or metal oxide clad silica particles, and molecularly imprinted silica particles, will also be included. Next, the individual preparation methods and their feasibilities will be collectively and critically compared and evaluated, being followed by conclusive remarks and future perspectives.

• Korean Journal of Organic Agriculture
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• v.13 no.2
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• pp.197-209
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• 2005

of Hangalku per plant sold for wild vegetables were 9.1g and 0.9g, and number of leaves was 10.8. Root fresh and dry weights of Hangalku per plant were 19.2g and 4.1g. Thirty five soil samples were collected from the native soils grown Cirsium japonicum DC., and mycorrhizal spores in soils were separated using wet-sieving methods. Number of mycorrhizal spores per 30g fresh soil sized over 500${\mu}$m, 355~500${\mu}$m, 251~354${\mu}$m, 107~250${\mu}$m and 45~106${\mu}$m were 0.6, 2.1, 6.0, 55.3 and 126, etc. Total number of mycorrhizal spores per 30g fresh soil were 190. Root infection by vesicles, hyphae and arbuscules were 13%, 4% and 3%, respectively. As a result of identification, mass propagated mycorrhizal spores by the host plant of Sudangrass were Glomus sp., Gigaspora sp., and Acaulospora sp., and so on.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.1
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• pp.120-124
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• 1994

Nine wind vegetables were analyzed for moisture, ash, crude protein, crude lipid and dietary fiber. Wild vegetables contained 33-53% of dietary fiber on a dry weight basis. Dalle (Allium monanthum) contained 49% total dietary fiber and 22% soluble dietary fiber and dodok(Codonopsis lanceolata) contained 55% total dietary fiber and 21% soluble dietary fiber. Wild 8% more dietary fiber than cultivated one. Water holding capacities of wild vegetables were higher than commercial wheat bran and soy fiber, but lower in oil absorption. When wild dodok and dalle were wet milled by blade grinding before sieving the dietary fiber content in dodok was increased from 55 to 83 % with increasing the dietary fiber content in dalle form 49% to 69%.

• Korean Journal of Plant Resources
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• v.27 no.2
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• pp.194-201
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• 2014

This study was carried out to investigate the characteristics and infection effects of AMF with soil samples collected at some sites in Gyeonggi province, Korea. AMF spore and characteristics of infection structure in upland plant root were observed as wet sieving and staining method, growth of Capsicicum annum was compared between treatment and non treatment. AMF spores isolated from each soil sample were ellipse or circle type and the colors were soft yellow and white. The colonization rate of AMF with soil infection of Zea mays roots was 13.3~83.3%, the rate of infected soil collected from Z. mays was higher on average. When compared to the growth of C. Annum with control after infection on C. annum, it wasn't showing many differences in fresh weight, dry weight and height, but the yield of fruit of C. annuum showed double than the control group.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.3
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• pp.267-273
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• 1995

The differences in rumen particle pool size, passage rate and rumen degradability in sheep receiving three varieties of orchardgrass hay harvested at pre-heading (H1), early-bloom (H2) and late-bloom (H3) were investigated using four ruminal-cannulated wethers (68 kg) fed 1,300 g of the hay once a day. Representative samples of whole rumen contents were collected at different times after feeding and the quantities of rumen particle pools [large particle pool (LPP), retained on a $1,180{\mu}m$ sieve; small particle pool (SPP), retained on a 47 but passed a $1,180{\mu}m$ sieve; and soluble fraction (SOL), passed a $47{\mu}m$ sieve (SOL)] were determined by a wet-sieving technique. The fullowing results were obtained: 1) The dry weight of whole rumen contents were significantly lower (p < 0.05) for HI than for H2 or H3. The reduction rate of whole rumen contents was slightly but significantly greater for HI that, the other hay varieties. 2) The LPP disappearance rates were 26.2, 25.3 and 21.7 g DM/h for H1, H2 and H3, respectively, and no statistical differences were found among the hay varieties. Appreciable changes were not observed with SPP and SOL throughout measurements for all hay varieties; however the SPP was markedly greater (p <0.05) for H2 and ill than for HI, while SOL did not differ among hay varieties. 3) The SPP passage rate (g DM/h) and effective rumen degradability (%) for HI, H2 and ill were, respectively, 9.7, 56.6; 16.9, 42.3; and 18.0, 28.9. The ruminal tum-over rate for SPP appeared to be higher for HI than for the other hay varieties.