• Journal of environmental and Sanitary engineering
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• v.14 no.2
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• pp.96-104
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• 1999

A questionary survey was conducted to investigate citizen's attitude to the treatment of food wastes in Miryang city. In this study, collection effectives was 87.8%, as 281 individuals among 320 individuals. After volume-base charge system, 86.8% of answers perform source separation and 60.9% of respondents separate everything of recycle goods. The majority of respondents discharge food waste using standard envelope. The biggest problems for deposition of the food wastes are offensive odor and worm for reasons of sanitation. Almost citizens think that the period of deposition suit from two days to three days. More than 90.0% of the citizens recognized that compost products made from food wastes and recognition of the people for the composting and composting facilities was affirmative. Majority of the respondents thought that the administration and the provincial government need activity publicity for the source separation fixations of the food wastes.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.2 s.245
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• pp.179-186
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• 2006

Dielectrophoresis has received considerable attention for separating nanotubes according to electronic types. Here we examine the effects of surface conductivity of semiconducting single-walled carbon nanotubes (SWNT), induced by ionic surfactants, on the sign of dielectrophoretic force. The crossover frequency of semiconducting SWNT increases rapidly as the conductivity ratio between the particle and medium increases, leading to an incomplete separation of ionic surfactant suspended SWNT at an electric field frequency of 10 MHz. The surface charge of SWNT is neutralized by an equimolar mixture of anionic surfactant sodium dodecyl sulfate (SDS) and cationic surfactant cetyltrimenthylammonium bromide (CTAB), resulting in negative dielectrophoresis of semiconducting species at 10 MHz. A comparative Raman spectroscopy study shows a nearly complete separation of metallic SWNT.

• Journal of Electrochemical Science and Technology
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• v.11 no.2
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• pp.155-164
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• 2020

Here we report our preliminary results about nickel phosphide (Ni-P) electroless coating on the surface of cellulose paper (CP) and its feasibility as the anode for lithium (Li) batteries. In particular, CP can act as a flexible skeleton to maintain the mechanical structure, and the Ni-P film can play the roles of both the anode substrate and the active material in Li batteries. Ni-P films with different P contents were plated uniformly and compactly on the microfiber strands of CP. When they were tested as the anode for Li battery, their theoretical capacity per physical area was comparable to or higher than hypothetical pure graphite and P film electrodes having the same thickness. After the large irreversible capacity loss in the first charge/discharge process, the samples showed relatively reversible charge/discharge characteristics. All samples showed no separation of the plating layer and no detectable micro-cracks after cycling. When the charge cut-off voltage was adjusted, their capacity retention could be improved significantly. The electrochemical result was just about the same before and after mechanical bending with respect to the overall shape of voltage curve and capacity.

• Microbiology and Biotechnology Letters
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• v.18 no.5
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• pp.517-524
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• 1990

The solubilization and desolubilization of proteins in CTAB/hexanol/isooctane reverse micellar system were investigated for the selective separation of proteins. Several proteins were used, including bovine serum albumin (BSA), pepsin, trysin and ribonuclease-a. Most proteins could be solubilized into reverse micelles in the pH range above the isoelectric point of each protein, where the net charge of protein was opposite to that of surfactant. However BSA was solubilized above pH 10, which is serveral pH units above the pI 4.9. The kinds of anions in aqueous phase influenced on protein solubilization while no significant trend was observed with different cations, Protein solubilization decreased with increase of the ion size in the order of F -, C1-, Br- and I -. The size of CTAB micelles did not change significantly with increasing ionic strength, but the solubilization decreased. Protein desolubilization showedropposite behaviors to the solubilization. Several model mixtures such as pepsin/ trypsin, pepsin/ribonuclease-a and BSAlribonucleaee-a were successfully separated from each other without changing enzymatic activities.

• Proceedings of the KIEE Conference
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• 2003.10a
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• pp.286-289
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• 2003

We investigated the influence of the properties of substrate material on the separation efficiency in microchip electrophoresis. We fabricated the various microchips and studied separation efficiency in microchannels composed of a single material such as quartz, glass, polydimethylsiloxane (PDMS), and polymethylmetha crylate (PMMA), as well as hybrid micro channels composed of different materials. New fabrication process for glass chip was suggested and some treatment is added to improve fabrication process in other chip. Separation efficiency was compared by measuring migration times and bandwidths of EOF and analytes in each microchip. The efficiency is the function of migration time, which is affected by the electroosmotic flow (EOF), and bandwidth of an analyte. EOF is highly dependent upon the characteristics of a microchannel wall surface. Migration time was more reproducible in silica chips than that of PDMS chip and more band broadening was observed in the microchip composed of hybrid material due to non-uniformity of surface charge density at the walls of the channel.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.340-343
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• 2011

Explosive bolts are reliable and efficient mechanical fastening devices having the special feature of a built-in release. The disadvantage of explosive bolt lies in that it is based on the high explosive effect of a pyrotechnic charge. The aim of the present work is to propose a pyrotechnically releasable mechanical linking device for two mechanical elements that does not suffer from such drawbacks. The pyro-lock using the pressure cartridge has the release characteristic without fragmentation and minimum pyro-shock. The present work is focused on the design, the interpretation of structure, the separation mechanism, separation force, and the results of various tests.

• Journal of the Korean Society of Visualization
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• v.19 no.1
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• pp.50-56
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• 2021

With the advances in recent nanotechnology, mass transport phenomena have been receiving large attention both in academic researches and industrial applications. Nonetheless, it is not clearly determined which parameters are dominant at nanoscale mass transport. Especially, membrane is a kind of technology that use a selective separation to secure fresh water. The development of great separation membrane and membrane-based separation system is an important way to solve existing water resource problems. In this study, glass fiber-based membranes which are treated by graphene oxide (GO), poly-styrene sulfonate (GOP) and sodium dodecyl sulfate (GPS) were fabricated. Mass transport parameters were investigated in terms of material-specific and structure-specific dominance. The 3D structural information of GO, GOP, and GPS was obtained by using synchrotron X-ray nano tomography. In addition, electrostatic characteristic and water absorption rate of the membranes were investigated. As a result, we calculated internal structural information using Tomadakis-Sotrichos model, and we found that manipulation of surface characteristics can improve spacer arm effect, which means enhancement of water permeability by control length of ligand and surface charge functionality of the membrane.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.1051-1054
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• 2006

Lots of information such as prescription transmitted to the drug store by the result of separation of medical activity from medicine one, EDI for billing medical charge to Health Care Public Cooperation and the returned opinion letter sent to doctor etc is scattered in the Web document made from XML. Especially information containing medical treatment charge is one of the materials that are revised frequently. It is the current situation that document is transmitted or form is made for distribution whenever this kinds of revision is occurred. In this thesis, DTD design and implementation for the information system regarding the rate of medical charge is studied based on XML which is used to calculate charges for the several activities including consulting and prescribing. Patient or patron as well as doctor, pharmacist and nurse are all interested in the information regarding the rate of medical charge. It aims everybody to easily obtain information about the rate of medical charge by querying it anytime, anywhere.

• Polymer(Korea)
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• v.31 no.2
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• pp.136-140
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• 2007

Charge transfer interaction as a hybridization mechanism of silsesquioxane/polymer was tested using carbazole (electron donor) group and dinitrobenzene (electron acceptor) group. Hybridization test was conducted using films made from mixing/casting of poly (carbazole-styrene) (PS/D) and dimtrobenzyl silsesquioxane (Cube/A), and transparent hybrid films were successfully obtained under some conditions. $^1H-NMR$ of PS/D and Cube/A, and W absorption test of hybrid films showed that one acceptor and one donor can form one charge transfer complex when no silsesquioxane molecule was included in films, but transparent hybrids with no phase separation were obtained only at acceptor/donor ratios less than 0.7 : 1. These results also suggested that on average 4 charge transfer complexes form per one silsesquioxane.

• Resources Recycling
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• v.18 no.1
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• pp.13-21
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• 2009

A research on material separation of EVA and PET mixture plastic waste using a triboelectrostatic separator has been carried out. It was found that PP was the best charging material to give the highest charge on the surface of EVA and PET mixture plastics with an opposite polarity. Therefore, a charger of pipe line type using PP material was manufactured for separation of EVA and PET mixture plastic waste. At optimum test conditions that used PP cyclone charger developed in this study, we could separate out PET with a glade of 98.7% and a recovery of 89.7%.