• Journal of radiological science and technology
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• v.42 no.6
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• pp.413-422
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• 2019

Heavy ion particle, represented carbon ion, radiotherapy is currently most advanced radiation therapy technique. Conventional radiation therapy has made remarkable changes over a relatively short period of time and leading various developments such as intensity modulated radiation therapy, 4D radiation therapy, image guided radiation therapy, and high precisional therapy. However, the biological and physical superiority of particle radiation, represented by Bragg peak, can give the maximum dose to tumor and minimal dose to surrounding normal tissues in the treatment of cancers in various areas surrounded by radiation-sensitive normal tissues. However, despite these advantages, there are some limitations and factors to consider. First, there is not enough evidence, such as large-scale randomized, prospective phase III trials, for the clinical application. Secondly, additional studies are needed to establish a very limited number of treatment facilities, uncertainty about the demand for heavy particle treatment, parallel with convetional radiotherapy or indications. In addition, Bragg peak of the heavy particles can greatly reduce the dose to the normal tissues front and behind the tumor compared to the photon or protons. High precision and accuracy are needed for treatment planning and treatment, especially for lungs or livers with large respiratory movements. Currently, the introduction of the heavy particle therapy device is in progress, and therefore, it is expected that more research will be active.

• Progress in Medical Physics
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• v.28 no.2
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• pp.67-75
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• 2017

Prior to the introduction of a medical apparatus based on heavy-ion medical accelerator in Korea, a study is needed on quality control in clinical operation for the safe and appropriate usage of the instrument. Data relevant for the study were obtained via information sharing sessions and visits by the Particle Therapy Co-Operative Group (PTCOG) and other related academic associations. Furthermore, investigative analysis of the European and Japanese performance evaluation guidelines for heavy ion, as well as research on relevant literature, were conducted. In addition, instrumental standards were analyzed through an investigation of the current usage status of the heavy-ion medical accelerator, and further analysis was conducted on the evaluation methods for the performance, safety, and significance of the instrument. Based on these analyses, regular quality control procedures for heavy-ion medical accelerators in hospitals and other institutes were extrapolated. It is hoped that the results of this study will facilitate hospitals that have introduced heavy-ion medical accelerators, or are considering the implementation of the instrument, in their understanding of the fundamental standards and capabilities of the treatment system, as well as in establishing and carrying out quality control procedures for clinical operations such that it will contribute to the safety of patients and the efficiency of medical practitioners.

• Journal of Environmental Science International
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• v.9 no.4
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• pp.325-330
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• 2000

The hydroxyapatite (HAp) for the present study was prepared by precipitation method in semiconductor fabrication and the crystallized at ambient to 95$0^{\circ}C$ for 30min in electric furnace. The ion-exchange characteristics of HAp for various heavy metal ions such as $Cd^{2+}, Cu^{2+}, Mn^{2+}, Zn^{2+}, Fe^{2+}, Pb^{2+}, Al^{3+}, and Cr^{6+}$ in aqueous solution has been investigated. The removal ratio of various metal ions for HAp were investigated with regard to reaction time, concentration of standard solution, amount of HAp and pH of solution. The order of the ions exchanged amount was as follws: $Pb^{2+}, Fe^{3+}>Cu^{2+}>Zn^{2+}>Al^{3+}>Cd^{2+}>Mn^{2+}>Cr^{6+}. The Pb^{2+}$ ion was readily removed by the Hap, even in the strongly acidic region. The maximum amount of the ion-exchange equilibrium for $Pb^{2+}$ ion was about 45 mg/gram of HAp. The HAp would seem to be possible agent for the removal of heavy metal ions in waste water by recycling of waste sludge in semiconductor fabrication.

• 한국초전도학회:학술대회논문집
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• 2008.08a
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• pp.19-19
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• 2008

• Journal of Soil and Groundwater Environment
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• v.28 no.6
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• pp.16-23
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• 2023

Heavy metal (Zinc, Cadmium, Lead) adsorption onto surface modified activated carbon was performed in order to better understand the effect of sodium ion addition to activated carbon. Surface modification methods in this research included water washing, nitric acid washing, and sodium addition after nitric acid washing. These surface modifications generated oxygen functional groups with sodium ions on the surface of the activated carbon.. This caused the change of the specific surface area as well as in the ratio of the carboxyl groups. Heavy metal adsorption onto sodium-containing activated carbon was the most among the three modifications. After the adsorption of heavy metals, the carboxyl group ratio decreased and sodium ions on the surface of the activated carbon were almost non-existent after the adsorption of heavy metals onto sodium-containing activated carbon. The results from this research indicated that ion exchange with sodium ions in carboxyl groups effectively improved heavy metal adsorption rather than electrostatic adsorption and hydrogen ion exchange.

• Journal of the Korean Society of Radiology
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• v.11 no.6
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• pp.437-442
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• 2017

Heavy ion therapy has a high cure rate for cancer cell. So many countries are introducing heavy ion therapy facility. When treating a cancer using heavy ion therapy, neutrons and gamma rays are generated and affect electronic equipment. A budget of about KRW 200 billion is needed to build a heavy ion therapy facility, and it takes more than five years to build it. Therefore it is important to observe the dose distribution in the treatment room using the monte carlo simulation before construction. In this study, we used the FLUKA of monte carlo simulation to investigate the dose distribution in the heavy ion treatment room.

• Journal of environmental and Sanitary engineering
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• v.13 no.1
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• pp.174-184
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• 1998

Biosorption characteristics were investigated to discuss the use of agar entrapped Spirulina to remove of heavy metal ions from polluted waters. Agar immobilized algae were used as bioadsorbent in continuous reactor for heavy metal ions removal. The process solution contains Pb, Cu, and Cd as single ion and binary ions. In the adsorption of single heavy metal ions by agar immobilized Spirulina, the adsorption reached within 1hr and observed diffusion limitation differed from the free algal cell adsorption. The optimum pH for the adsorption of heavy metals was 4.5 but the influence of pH decreased less than that of free algal cell. Also, the adsorption characteristics of single heavy metal ions with agar immobilized Spirulina fitted the BET isotherm. Both of experiments of free algal cell and agar immobilized algae showed higher removal efficiency in the single ion solutions than binary ions solutions. The experimental results in the packed column with agar immobilized algae were over 90% of removal efficiency for the Pb, Cu, and Cd in single ion solutions.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.231-232
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• 2002

We have been developing microvolume LET counter in order to measure the three-dimensional LET distribution of the therapeutic heavy ion radiation volumes in the water phantom. With help of the technique of cathode induced carhge readout, this detector has a rectangular (box-shape) sensitive volume of which size is about 1 mm$^2$ and 2mm (depth).

• Progress in Superconductivity and Cryogenics
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• v.18 no.2
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• pp.25-29
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• 2016

High charge state electron cyclotron resonance (ECR) ion source is important on the performance of heavy ion accelerators. In this paper, a low temperature superconductor (LTS) was used to make a hexapole coil for an 18-GHz ECR ion source. Several hexapole structures, including racetrack, graded racetrack, and saddle were implemented and analyzed for the hexapole-in-solenoid ECR ion source system. Under the appropriate radial confinement field, the smaller outer radius of hexapole can be better for the solenoid design. Saddle hexapole was selected by comparing the wire length, maximum outer radius of the hexapole, the Lorentz force at the end part of the hexapole and the maximum magnetic field in the coil. Based on saddle hexapole, a new design for hexapoles, the snake hexapole, was developed in this paper. By comparative analysis of the Lorentz force at the end part of the saddle and snake hexapoles, the snake hexapole is much better in the ECR ion source system. The suggested design for the ECR ion source with the snake hexapole is presented in this paper.

• Journal of environmental and Sanitary engineering
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• v.14 no.1
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• pp.80-87
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• 1999

According to the fact that algae, which is usually used as a biosorbent, contains chlorophyll, we used the chlorophyll as an adsorbent. In this study, chlorophyll is immobilized by agar, which was made of platan, oak, ginkgo and pine. We investigated the removing capacity of biosorbents to toxic heavy metals (Pb, CU, Cd, Zn) in the single ion solution. Then the experimental parameters were pH, reaction time and concentration of heavy metal ions.The optimum conditions for the adsorption of heavy metals were as follows : pH range was 4~5, reaction time was 40mon, and the highest ratio of the removing rate was 50~70 ppm. The order of the amount of Pb, Cu and Cd removed was specified as oak > ginkgo > pine > platan in these conditions and as pine > ginkgo > oak > platan at Zn. Fro the results of the desorption experiments, we found that the heavy metal with the highest ratio of desorption in the single ion adsorbent was Cu.