• Journal of the Korean Chemical Society
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• v.38 no.9
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• pp.660-666
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• 1994

The effects of temperature and flow rate of eluent on the separation of adjacent lighter lanthanide pairs (La : Ce, Ce : Pr, Pr: Nd) have been studied with displacement chromatography. Two serial columns packed with Amberlite 120 cation exchange resin are used for loading and separation. The retaining ion is $H^+$ ion and the eluent is 0.012M and 0.015M of EDTA solution. The columns and the eluent are maintained at the temperature of 90$^{\circ}C$ and pressurized to reduce vaporizing in the ion-exchange resin column. The eluated solution is analyzed directly with ICP-AES. The separation factors of the lanthanide pairs, La: Ce, Ce :Pr, and Pr: Nd, are 4.6, 2.8, and 1.9, respectively and are higher than that from theoretical calculation at 25$^{\circ}C$. When the flow rate is reduced from 2.5 ml/min to 1.5 ml/min, the HETP is reduced from 1.60 cm to 0.88 cm. The separation efficency can be improved at lower flow rate of eluent and higher operating temperature. The recoveries of pure lanthanides than 99.9% are 49∼77% from this separation.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.4
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• pp.69-76
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• 2002

The aim of this study is to provide fundamental informations that make it possible to use a cool stream and a hot stream simultaneously. We changed the pressure of compressed air that flows into a tube, the inner diameter of orifice that a cold stream exits, and the mass flow rate ratio. And in each case, we measured the temperature of a cold stream and a hot stream in each exit of a tube. Also we measured the axial and the radial temperature distribution in internal spare of a tube. From the study, fellowing conclusive remarks 7an be made. First, As the number of nozzles increase, separation point move into the hot exit. Second, When we use guide vane type nozzle, the axial temperature distribution constant over the 0.75 of air mass flow rate radio. Third, When we use Spiral type nozzle, axial and radial temperature distribution in the inner space is higher than another nozzle. Fourth, Axial and radial temperature distribution in the inner space vortex-tube is determined by separation point. And separation point is moved by changing of air mass flow rate ratio. At last, A heating apparatus is possible far vortex-tube to use.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.446-448
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• 2000

In this study, we investigated the theoretical and experimental study for separation of solid-liquid suspensions of water and fine particles using acoustic standing wave. When the acoutic force was not applied, the separation efficiency was decreased as flow rate was increased. When it was applied, the separation efficiency was maintained over 95%.

• Journal of Animal Reproduction and Biotechnology
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• v.35 no.2
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• pp.142-148
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• 2020

The research work was undertaken to determine an effective fertilization medium, sperm separation method and sperm capacitating agent for optimum in vitro fertilization (IVF) rates of indigenous zebu cow oocytes. In experiment 1, tissue culture medium (TCM 199), Tyrode's albumin lactate pyruvate (TALP) and Brackett and Oliphant (BO) medium were used as basic medium for IVF of oocytes of indigenous zebu cows. In experiment 2, three sperm separation methods namely centrifugation, swim up and percoll gradient methods were used for separation of motile and viable spermatozoa for IVF. In experiment 3, for capacitation of spermatozoa, IVF medium supplemented with the heparin, mixture of penicillamine, hypotaurine and epinephrine (PHE) or the combination of heparin with PHE were used for fertilization. In vitro culture (IVC) of presumptive zygotes was done in modified synthetic oviduct fluid (mSOF) medium using standard procedure 24 h after sperm-oocytes co-culture. The cleavage rate was determined to evaluate the efficacy of fertilization medium, sperm separation method and sperm capacitating agent 24 h after IVC. The cleavage rate was higher in oocytes fertilized in TALP (63.3%) than in TCM 199 (47.5%) (p < 0.05). The cleavage rate was higher in oocytes fertilized by spermatozoa separated by percoll gradient method (62.3%) than by centrifugation (51.6%) (p < 0.05). The cleavage rate of oocytes was higher when insemination was done with spermatozoa capacitated in TALP supplemented with heparin and PHE (61.3%) compared to control (40.9%) (p < 0.05). In conclusions, TALP based medium and percoll gradient sperm separation followed by capacitation with combination of heparin and PHE are suitable for IVF of indigenous zebu cow oocytes in Bangladesh.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.5
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• pp.599-606
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• 1995

The feasibility of foam separation to remove protein produced from fish culture water was investigated, By assuming foam separation column as a single well-mixed pool, a simplified model for foam separator conditions was alse studied under the batch operation. The model indicated that the protein removal could be described as a first-order reaction whose rate increases with both superficial air velocity and protein concentration in the bulk solution. from ,the results of an experimental study on the effects of superficial air velocity, the protein concentration, temperature, and pH on protein removal, the superficial air velocity and initial protein concentration in bulk solution were found to be important operational factors. Other experimental results important that foam separator operated under batch conditions would be considered as a completely mixed reactor. The protein removal rate by foam separation process was increased proportionally with the superficial air velocity, and the adsorptive removal rate of protein was found to obey Langmuir adsorption formula. The preposed simplified model was verified with the experimental data obtained from this study. Under the experimental range used, both temperature and pH did not affect the protein removal.

• Journal of Environmental Science International
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• v.20 no.8
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• pp.1011-1019
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• 2011

The objective of this research is to evaluate optimal conditions of permeability and selectivity on the polysulfone membrane for efficiency of separation of $CH_4$ by checking four factors which are temperature, pressure, gas compositions and gas flow rates. When higher pressure was applied at the input, lower efficiency of recovery of $CH_4$ and higher efficiency of separation of $CH_4$ were shown. It has the tendency to show lower efficiency of recovery of $CH_4$ and higher efficiency of separation of $CH_4$ at the output as higher temperature at input. The lower flow rates make higher efficiency of recovery of $CH_4$ and lower efficiency of separation of $CH_4$. Finally, over 90% efficiency for $CH_4$ separation and recovery conditions are temperature ($-5^{\circ}C$), pressure (8 bar), gas composition rate (6:4) ($CH_4:CO_2$) and gas flow rate ($5\ell$/min). These conditions make higher separation and recovery efficiency such as 90.1% and 92.1%, respectively.

• Membrane and Water Treatment
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• v.10 no.2
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• pp.127-137
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• 2019

The D2EHPA/TBP co-extractants immobilized PolyHIPE membrane can be used for the selective separation of Mn (II) from Co (II). By solvent-nonsolvent method, D2EHPA/TBP co-extractants can be effectively immobilized into PolyHIPE membrane. The pore structure of PolyHIPE membrane and the presence of TBP enhance the stability of immobilized co-extractants. The optimal operating conditions for the separation of Mn (II) and Co (II) are feeding phase at pH 5.5, sulfuric acid concentration in the stripping phase of about 50 g/L and stirring speed at 400 rpm. The D2EHPA/TBP co-extractants ratio of 5:1 shows synergetic effect on Mn/Co separation factor about 22.74. The removal rate and recovery rate of Mn (II) is about 98.4 and 97.1%, respectively, while for Co (II) the transport efficiency is insignificant. The kinetic study of Mn (II) transport shows that high initial flux, $J_f^o=80.1({\mu}mol/m^2s)$, and maxima stripping flux, $J_s^{max}=20.8({\mu}mol/m^2s)$, can be achieved with D2EHPA/TBP co-extractants immobilized PolyHIPE membrane. The stability and reusability study shows that the membrane can maintain a long term performance with high efficiency. High purity of Co (II) and Mn (II) can be recovered from the feeding phase and stripping phase, respectively.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.921-931
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• 2020

This study was carried out to determine the factor of a separating system according to the pepper varieties and the absence of a card cleaner system. The pepper varieties of Jeokyoung and AR-Legend were transplanted on November 20, 2019 and tested on March 18, 2020 with a harvesting speed of 0.2 m·s-1 for 10 pepper plants. The performance evaluation was determined by analyzing the separation efficiency of the peppers and the foreign matter mixing rate. The pepper harvester with a card cleaner showed a higher separation efficiency of the peppers compared to the pepper harvester without a card cleaner. The average separation efficiency of peppers on the pepper harvester with a card cleaner was higher at 13.5% for Jeokyoung and 1.9% for AR-Legend than that without a card cleaner. The mixing ratio of foreign materials on the pepper harvester with a card cleaner was lower at 8.7% and 2.5% for Jeokyoung and AR-Legend than that without a card cleaner, respectively. For the two-way ANOVA results according to the variety and the card cleaner, there was no effect on the separation efficiency of the peppers, but there was an effect on the foreign matter mixing rate.

• Progress in Superconductivity and Cryogenics
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• v.24 no.3
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• pp.12-18
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• 2022

In recent years, the impact of microplastics (MPs) on ecosystems is a serious problem. Since MPs are difficult to recover once they are dispersed into the environment, it is important to remove them at the source. We proposed a magnetic separation of primary MPs (plastics manufactured in minute sizes) sized 10-100 ㎛ that has not been removed in the sewage process, based on the magnetic seeding process. In this study, we used magnetite as a magnetic seeding agent, and conducted magnetic separation experiments in the continuous process using a superconducting solenoidal magnet to investigate the feasibility of practical magnetic separation system of MPs. As a result, 85% separation rate was obtained by continuous separation using high gradient magnetic separation (HGMS) with hydrophobically treated magnetite as a magnetic seeding agent.

• Journal of Biosystems Engineering
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• v.6 no.2
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• pp.33-47
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• 1982

To modernize the conventional rice post production technology and reduce grain losses, a transition toward the wet-paddy threshing system has been strongly demanded. The head-feeding type thresher with pneumatic separation has been used dominantly for threshing dried-paddy, but some adverse effects in separation performance for threshing wet-paddy is encounterred. In order to solve the problems, the development of thresher with an additional oscillating sieve to the conventional pneumatic separation has been recommanded. This study was intended to evaluate the separating performance of thresher with oscillating sieve which was attached additionally to the conventional auto-thresher equipped with separation system of blower and suction fan. For different feed rates and rice varieties, wet-and dry-material were tested with threshers attached with and without oscillating sieve. Results of the study are summarized as follows: 1. When the feed rates were 480 and 640 kg/hr, there was no statistically significant difference in power reqirements between the threshers with and without an additional sieve device for both dry-and wet-threshing. However, when the feed rate was 960 kg/hr, power requirements of thresher without sieve were greater for wet-paddy threshing than the thresher with the additional sieve separator by about 20% points. 2. With additional oscillating sieve device, the ratios of total weights of whole grains including grains with branch let and damaged grains to the total output did not show statistical difference among the feed rates. However, with pneumatic separation the ratio was decreased as the level of feed rate increased. 3. The total amount of grains with branchlet (including broken panicle) increased with the moisture content. For both the wet-and dry-material threshing with the additional oscillating sieve, the percent of grains with branchlet to the total output decreased greatly as the feed rate increased. 4. The output of the damaged grains increased as moisture content decreased. Especially, for the dry-paddy threshing, the additional sieve separating device produced more damaged grains than the pneumatic separation at all feed rates. 5. Generally, for dry paddy threshing, the separating performance of the thresher with the additional sieve device was better at all feed rates, showing greater difference with increasing feed rates. 6. Separating losses were greater with the pneumatic than sieve separation for both the wet-and dry-threshing. 7. The overall comparison of separating performance of threshers tested with and without an additional sieve device showed that the former was more effective than the latter for the dry-material threshing. However, for the wet-paddy threshing, the separation performance with a sieve device was better than the pneumatic only when the feed rate was high.