• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.1
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• pp.8-12
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• 2010

Purpose: In $^{18}F$-FDG automated synthesizer, deliver is done in automated mode after synthesis until the dispenser. After the delivery, the yield is calculated from the radioactivity which was read by the dose calibrator located in the dispenser. However, when the distance between the automated synthesizer and the dispenser is far, there are $^{18}F$-FDG residues, which results in loss of the amount of $^{18}F$-FDG. This study investigated the usefulness of a method that minimizes $^{18}F$-FDG residues. Materials and Methods: The structure of the tubing between the (TRACERlab Mx FDG; GE.) and the dispenser is that the distance is 8 m and the internal diameter is 1/16 inch. The synthesis process of The module goes through the synthesis process of trap, synthesis, delivery in the automated module. The time taken for synthesis is about 25 to 26 minutes, after which rinsing is done. However, after rinsing, as the distance of the tubing increased, there were 10~13% of $^{18}F$-FDG residues. Therefore, a method of using push syringe and $N_2$ gas in manual mode to minimize $^{18}F$-FDG residues is analyzed. Results: In manual mode, there were $^{18}F$-FDG residues of 4~5% for the push syringe, and there were $^{18}F$-FDG residues of less than 1% for the $N_2$ gas, which showed that the method using $N_2$ gas had superior usefulness. Also, there were no $^{18}F$-FDG residues in the cleaning the next day. Conclusion: The distance between the synthesizer and the dispenser needs to be reduced as much as possible, to reduce the rate of loss of $^{18}F$-FDG resulting from the distance of the tubing. However, in case the distance between the synthesizer and the dispenser has to be increased due to the system structure, using push syringe and $N_2$ gas simultaneously is a useful method for minimizing $^{18}F$-FDG residues.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3187-3190
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• 2007

Elastin-Like polypeptide (ELP) composed of elastin-based repeating units is an artificial biomaterial which is biocompatible and non-immunogenic. ELP shows a characteristic inverse phase transition between hydrophobic and hydrophilic phase by external stimuli such as salt, pH and temperature. In this study, ELP coated PS (polystyrene) beads are packed in tubing and the thermo -responsive flow characteristics of the packed bed are investigated. Preliminary test results show that the control of the fluid flow can be achieved by using the temperature driven phase transition effect of the ELP coated beads in a microchannel.

• Applied Biological Chemistry
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• v.41 no.8
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• pp.583-586
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• 1998

Porous ceramic cups are used for monitoring ion concentration in soil solutions in various time course and depth. A soil solution sampler was constructed in laboratory by inserting pliable perfluoroalkoxy(PFA) tubings into porous cup through holes in PVC rod segment which plugged top opening of the porous cup. The system was installed in drip irrigated soil in a vertical position, and nitrogen movement below the drip basin was monitored. To collect soil solution, vacuum in the cup was applied with a hand vacuum pump. The samples obtained were sufficient enough to run quantitative analyses for a number of chemicals. Nitrogen transformation and movement could be well defined, and the system seemed to be relevant to the other soil solution samplers in monitoring chemical movement in soil. Although this system has general deficiencies found in the other samplers using ceramic cup, it could be easily constructed at a low cost. Since the tubing was pliable, the cups could be installed in horizontal position, and this allows installations of the cups at more precise depth increments and also more precise samplings of soil solution at each depth.

• Journal of the Korean Ceramic Society
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• v.29 no.12
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• pp.919-925
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• 1992

Continuous synthesis process for monodispersed zirconia powders with ultrasonic wave mixing was developed. Reactant solutions were flowed through a T-tube with small diameter and then mixed in a microscale with ultrasonification. Reaction and aging were followed during the mixed solution of reactants is in plug flowing through a narrow long teflon tubing. Zr(n-OC4H9)4 in ethanol and H2O in ethanol were used as reactants. From this process monodispersed, spherical, non-agglomerated, singlet hydrated zirconia powders with 0.6 $\mu\textrm{m}$ average size were obtained. Geometrical standard deviation of the particle size distribution was less than 1.2 with ultrasonic mixing, and the geometrical standard deviation was not affected by the flow rate of the reactants.

• KSBB Journal
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• v.15 no.4
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• pp.380-387
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• 2000

An extractive fermentation process using pervaporation was studied in a 7 liter fermentor. Pervaporation was performed using a silicone membrane module and a low-acid-producing strain Clostridium acetobutylicu, B18 was used to produce butanol. In batch culture without pervaporation pH 5.5 and initial glucose concentration of 60 g/L resulted in the highest butanol productivity (0.216 g/L$.$h) with butanol yield of 0.261 Butanol flux through the membrane was best at 2.0 L/min-tubing of air flow rate In batch and fed-batch fermentation glucose consumption rate increased by 1.3 times with pervaporation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.60-63
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• 2004

An innovative in-core neutron flux mapping system has been developed and applied successfully for service in a commercial pressurized water reactor. With the benefit of double indexing path selector (Dip $s^{ⓡ}$) mechanism, the reliability of the detector drive system has been improved five times higher than that of conventional systems, and the problems caused by the serious friction generated between the detector cable and guide tubing has been solved completely because the Dip $s^{ⓡ}$ architecture allows the detector guide tubings to have larger curvature and shorter length in nature. The simple and fast maintenance is particularly emphasized in the detector drive system to secure minimum radiation exposure to the maintenance personnel by optimizing the number of components and providing easy access to the components. The programmable logic controller based digital controller with Window $s^{ⓡ}$ based operator s console provides fully automated and user friendly operation and maintenance support means.

• Environmental Analysis Health and Toxicology
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• v.16 no.4
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• pp.171-179
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• 2001

A new passive sampler was developed, improving SPMD (Semipermeable Membrane Devices) that contained triolein in nonporous, low-density polyethylene layflat tubing. Experiments to measure PAHs concentration were carried out at four sites (Dukpo, Sochi, Sohwonggando, Yeonmok) on the southern coast of Korea that were contaminated by oil spills. Passive samplers were deployed at 4 and 8 week intervals at each site. Results showed that bioconcentration levels of PAHs were increased in proportion to exposure duration from all sample sites and accumulation in the passive sampler was much higher than in biota at the Dukpo site. Results of these tests suggest that new passive sampler is a useful tool for measuring bioconcentration organic compounds in aquatic environments.

• Journal of environmental and Sanitary engineering
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• v.16 no.3
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• pp.8-13
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• 2001

This study was carried out effect of red ginseng extract(1.0g/kg) on organotin compounds (10, 20 and 40 mg/kg) which poisons against some organs like thyroid gland, liver, kindey, testis, ovary, serum immuinty and sex hormone activity of rats were examinned by gastric tubing for 3 weeks. The weight of each organ in TBTO treated group were significantly increased other organs which excepted kinedy in males and only liver in females.(p<0.05, p<0.01). In case of Immunity activity of each sex, IgM level was small change comparsion with that of control group in all sex. but IgG level was significantly decreased females rather than males comparsion with that of control group.(p<0.05, p<0.01) In case of sex hormone activity, the testosterone activity of males and the estradiol activity of females were significantly decreased rather than the control group. on the other hand, red singsong treated group was only significantly increased estradiol activity.( p<0.05, p<0.01)

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.202-202
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• 2006

With a modern size exclusion chromatography (SEC) column, molecular weight analysis of a polymer sample takes about 10 min. However, it is desirable to reduce the analysis time further, in particular, for high throughput measurements required in combinatorial analyses or 2D-HPLC analyses. We implemented the high temperature SEC for the purpose. By inserting a narrow bore tubing between the column and the detector, a sufficient backpressure can be maintained to prevent the mobile phase from boiling and the effluent is cooled down enough when it reaches the detector. Therefore, a normal SEC detector can be used without any modification. The SEC resolution is greatly improved at the elevated temperature at high flow rate which allows high speed operation.

• Journal of Chest Surgery
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• v.25 no.10
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• pp.1048-1054
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• 1992

With use of a simple, inexpensive and nonpharmacological program for blood conservation, 24 consecutive patients underwent elective or urgent coronary artery bypass grafting without need of homologous red cell transfusions and /or fresh frozen plasma transfusions in 16 patients[66.7%]. Left internal mammary artery graftings were done in 18 patients[75%], with supplemental saphenous vein grafts in all. Intraoperatively, autologous heparinized blood was removed before bypass and retransfused at the conclusion of ext-racorporeal circulation. The volume remaining in the oxygenator and tubing set was returned without cell processing or hemofiltration. Using the hard-shell cardiotomy reservoir from the oxygenator, autotransfusion of the shed mediastinal blood was continued hourly by the next early;norning. The mean postoperative mediastinal blood loss was 364$\pm$234ml, whereas 553$\pm$383ml was autotransfused. 4 patients [16.7%] received homologous blood and an additional 4 patients[16.7%] fresh frozen plasma. Thus, in total, 16 patients[66.7%] were not exposed to any homologous blood products during the hospital stay. At discharge, the mean hemoglobin concentration was 10.3$\pm$1.6g /dl. Postoperative complications were few and there was no hospital death.