• Journal of Korea Foundry Society
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• v.36 no.1
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• pp.24-31
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• 2016

CD4MCU duplex stainless steel with gadolinium was fabricated as a neutron absorbing material by the air induction melting method. The gadolinium formed intermetallic compounds of Cu-Gd-Fe. There were no significant differences in hardness or ultimate tensile strength between experimental alloys. With the addition of gadolinium the yield strength of the cast alloy significantly increased, from $478.8{\pm}11.6$ to $514.2{\pm}29.9MPa$, whereas elongation of the cast alloy decreased with the addition of gadolinium, from $26.0{\pm}7.1$ to $7.0{\pm}2.5%$ due to the formation of gadolinium based intermetallic compounds.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.8 no.2
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• pp.113-118
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• 2022

Gadolinium neutron capture therapy (Gd-NCT) is a precision radiation therapy that kills cancer cells using the neutron capture reaction that occurs when ¹⁵⁷Gd hits thermal neutrons. ¹⁵⁷Gd has the highest thermal neutron capture cross section of 254,000 barns among stable isotopes in the periodic table. Another stable isotope, ¹⁵⁵Gd, also has a high thermal neutron trapping area (~ 60,700 barns), so gadolinium that exists in nature can be used as a Gd-NCT drug. Gd-NCT is a mixed kinetic energy of low-energy and high-energy ionizing particles, which can be uniformly distributed throughout the tumor tissue, thereby solving the disadvantage of heterogeneous dose distribution in tumor tissue. The Gd complexes of small-sized molecule are widely used as contrast agents for magnetic resonance imaging (MRI) in clinical practice. Therefore, these compounds can be used not only for diagnosis but also therapy when considering the concept of Gd-NCT. This multifunctional trial can look forward to new medical advance into NCT clinical practices. In this review, we introduce gadolinium compounds suitable for Gd-NCT and describe the necessity of image guided Gd-NCT.

• Nuclear Engineering and Technology
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• v.53 no.6
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• pp.1887-1892
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• 2021

The effect of gadolinium and boron on the texture development and magnetic properties of the texture controlled 23Cr-10NiCu duplex stainless steels were studied to develop a high performance neutron and electromagnetic shielding material. The 23Cr-10NiCu base alloy is composed of 60% of austenite and 40% of ferrite, whereas, the 23Cr-10NiCu-0.5Gd-0.8B modified alloy is composed of 66% of austenite, 27% of ferrite and 7% of CrFeB intermetallic compounds. The gadolinium and boron addition to the 23Cr-10NiCu base alloy increased mechanical properties. Microstructure observation showed that the small addition of 0.5 wt% gadolinium and 0.8 wt% boron to the alloy retarded to form texture at the same hot rolling conditions, and improved the maximum magnetism, residual magnetism and coercive force about 3%, 122% and 120%, respectively.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.5 no.1
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• pp.61-68
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• 2019

Purine type compounds has been recently reported to cause the death for lung cancer cell, related to microtubules-targeting agents (MTAs). Therefore it can be used to develop as theranostic radiopharmceuticals in nuclear medicine or gadolinium-based MRI imaging agents by chelate chemistry. In the study, we tried to chemically bind a DOTA chelate on the end of purine compound and obtained a specific conjugate of DOTA-purine for metal coordination. In particular, radiometal like Cu-64, for the development of MRI imaging agents, can be utilized to choice good candidates before the synthesis of gadolinium complexes. By the screening of radioisotope technique, Gd-DOTA-purine type complex was successfully prepared and showed MRI imaging for lung cancer cell into the mouse model.

• Journal of the Korean Applied Science and Technology
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• v.23 no.3
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• pp.207-214
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• 2006

$Y_{2-x}Gd_xO_3:Eu$, phosphors for plasma display panel(PDP), were prepared by Pechini method which use yttriun chloride, gadolinium chloride, and europium oxide as starting materials. This method is a different way to the synthesis of europium(Eu)-doped phosphors, and it consists of the formation of a polymeric resin obtained by polyesterification between metal chelate compounds and a polyfunctional alcohol. This needs lower temperature than solid-state synthetic method. The prepared $Y_{2-x}Gd_xO_3:Eu$ phosphor particles had spherical shape and coherence. The luminescence intensity of $Y_{2-x}Gd_xO_3:Eu$ phosphor particles increased according to the increase of gadolinium(Gd) content(to 0.8mol%), and $Y_{1.2}Gd_{0.8}O_3:Eu$ phosphors had the highest luminescence intensity under vacuum ultra violet(VUV) excitation. The optimum concentration of Eu in the phosphor and optimum calcination temperature was 3wt% and $1100^{\circ}C$. The prepared phosphors were consist of particle, and its size was between 100nm and 150nm. Among the different polyfunctional alcohols, diethylene glycol(DEG) improved the luminescence intensities of phosphors more than other additives. The Pechini method proved that it is demonstrated to be suitable for the synthesis of phosphors used in PDP.

• Nuclear Engineering and Technology
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• v.34 no.1
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• pp.80-89
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• 2002

A laboratory investigation of the behavior of radioactive metals under the various waste combustion atmospheres was conducted to predict the parameters that influence their partitioning behavior during waste incineration. Neodymium, samarium, cerium, gadolinium, cesium and cobalt were used as non-radioactive surrogate metals that are representative of uranium, plutonium, americium, curium, radioactive cesium, and radioactive cobalt, respectively. Except for cesium, all of the investigated surrogate metal compounds converted into each of their stable oxides at medium temperatures from 400 to 90$0^{\circ}C$, under oxygen- deficient and oxygen-sufficient atmospheres (0.001-atm and 0.21-atm $O_2$). At high temperatures above 1,40$0^{\circ}C$, cerium, neodymium and samarium in the form of their oxides started to vaporize but the vaporization rates were very slow up to 150$0^{\circ}C$ . Inorganic chlorine (NaCl) as well as organic chlorine (PVC) did not impact the volatility of investigated Nd$_2$O$_3$, CoO and Cs$_2$O. The results of laboratory investigations suggested that the combustion chamber operating parameters affecting the entrainment of particulate and filtration equipment operating parameters affecting particle collection efficiency be the governing parameters of alpha radionuclides partitioning during waste incineration.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.26 no.3
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• pp.237-252
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• 2016

Objectives: This study was conducted in order to improve the current understanding of rare earths(RE) and to provide supporting data for establishing occupational health policies by reviewing the toxicological data and issues caused by the use of RE compounds in various fields. Methods: To evaluate the potential toxicity of RE from the viewpoint of occupational health, we summarized extensive reviews of relevant articles in the toxicology(animals and cells), occupational health and safety, and epidemiologic literature. Results: Although occupational RE exposure occurs extensively from ore mining and refining to end users in various industrial applications, epidemiologic study has not been performed among workers up to now. Bioaccumulation and adverse effects of RE have also been mentioned in ore mining regions and nearby residences, but safety standards for each process are insufficient. Moreover, because new commercial recycling technology will soon be applied to various industries, regulation and policies are needed for preventing abuse of recycling. In the results of animal toxicity for a few REs(mostly cerium, lanthanum, and gadolinium), toxicities of liver, lung, blood, and the nervous system were identified due to oxidative stress, but study of long-term RE exposure is required. Understanding the dual effect for RE and discovery of biomarkers pose a scientific challenge in further mechanism studies. Conclusions: In the future, additional hazard evaluation based on animal experiments is required, alongside continuous research for developing analytical methods and discovering biomarkers. Finally, RE occupational health and safety management needs to be integrated into the sustainable use of these materials.