• Journal of the Korean Society of Industry Convergence
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• v.27 no.2_2
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• pp.437-443
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• 2024

The purpose of radiological Dispersal Device(RDD) is to kill people by explosives and to cause radiation exposure by dispersing radioactive materials. And It is a form of explosive that combines radioactive materials such as Co-60 and Ir-192 with improvised explosives. In this study, we tested and evaluated whether it was possible to read the internal structure of an explosive using X-rays in a radioactive explosive situation. The improvised explosive device was manufactured using 2 lb of model TNT explosives, one practice detonator, one 9V battery, and a timer switch in a leather briefcase measuring 41×35×10 cm³. The radioactive material used was the Co-60 source used in the low-level gamma ray irradiation device operated at the Advanced Radiation Research Institute of the Korea Atomic Energy Research Institute. The radiation dose used was gamma ray energy of 1.17 MeV and 1.33 MeV from a Co-60 source of 2208 Ci. The dose rates are divided into 0.5, 1, 2, and 4 Gy/h, and the exposure time was divided into 1, 3, 5, and 10 minutes. Co-60 source was mixed with the manufactured explosive and X-ray image reading was performed. As a result of the experiment, the X-ray image appeared black in all conditions divided by dose rate and time, and it was impossible to confirm the internal structure of the explosive. This is because γ-rays emitted from radioactive explosives have higher energy and stronger penetrating power than X-rays, so it is believed that imaging using X-rays is limited By blackening the film. The results of this study are expected to be used as basic data for research and development of X-ray imaging that can read the internal structure of explosives in radioactive explosive situations.

• Sim-seong Yeon-gu
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• v.33 no.2
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• pp.99-140
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• 2018

After a careful review on the concept of transference from the perspective of analytical psychology with Jung's view in the center, the author had proposed that an interpretation for the whole series of 'Rosarium Philosophorum' including its posterior part to which Jung didn't refer in 'The Psychology of The Transference' be carried out for the genuine understanding of transference. The symbolic meaning of the twenty woodcuts' pictures in 'Rosarium Philosophorum' could be interpreted as the alchemical stages of blackening, whitening, yellowing, reddening and etc. The transformation through each stage could be associated with the process of psychotherapy as well as individuation process and the meaning of transference could be elucidated as a kind of initiating process for the individuation process. The eastern traditional thoughts on psychic transformation and human development were also compared. The individuation process would be coexistent with the development of human relationship including the therapeutic relationship and the concept of human (人 and 人間) in the eastern traditional thoughts would have many meaningful implications for further studies.

• Food Science and Preservation
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• v.6 no.2
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• pp.148-152
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• 1999

Philippine bananas were ripened at various temperatures(18$^{\circ}C$, 21$^{\circ}C$ and 25$^{\circ}C$) for 5 days and stored at 13$^{\circ}C$ and ambient temperature(13-20$^{\circ}C$) for 16 days. Their quality changes were evaluated during the storage. The color chart number and soluble solids of bananas before storage showed 4.2-5.2 and 18.7-18.8$^{\circ}$ Bx at 18$^{\circ}C$ and 21$^{\circ}C$ ripening and 5.5 and 20.1 $^{\circ}$Bx at 25$^{\circ}C$ ripening, respectively. Weight losses reached about 1% around 10 days in all storage conditions. Soluble solids increased initially for 4-6 days and then decreased slightly. Color chart number changed from 4.2-5.5 after ripening to 7 after 2-4 days storage. Blackening of 18$^{\circ}C$ and 21$^{\circ}C$ ripened bananas occurred after 4 days storage at 13$^{\circ}C$ and after 2 days storage at ambient temperature. Decay of 18$^{\circ}C$ and 21$^{\circ}C$ ripening bananas increased from 2.1% after 6 days at 13$^{\circ}C$ storage and 4.2% after 4 days at ambient temperature storage to 75-100% within 2-4 days after that times. The decay of 25$^{\circ}C$ ripened bananas rapidly increased after 2 days at 13$^{\circ}C$ storage and at the initial at ambient temperature storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.57-63
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• 2002

As an alternative to methyl bromide (MeBr) fumigation for the control of quarantine pests of pears (Pyrus pyrifolia cv. Niitaka), the effect of gamma irradiation (0.5~3 kGy) was comparatively investigated. Insects found in the pears were identified Tetranychus urticae Koch and Panonychus ulmi Koch, which were of quarantine importance. These insects were easily destroyed by MeBr even one day after fumigation. Whereas irradiation at 0.5~2 kGy was not enough to reach the mortality, even if 3 kGy showed the same mortality as MeBr after 17 days of treatment. Respiration of pears was stimulated by both increased doses of irradiation and MeBr fumigation. The rates of surface blackening and core browning were accelerated by MeBr rather than higher doses of irradiation. While the changes in flesh firmness and surface color were more apparent in irradiated samples at above 2 kGy than MeBr. There were negligible differences in the contents of titratable acidity, acetaldehyde and ethanol by the treatment conditions except for 3 kGy-irradiated group. Sensory evaluation showed that mere than 1 kGy was the threshold to induce the significant changes in quality of pears.

• Journal of the Mineralogical Society of Korea
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• v.32 no.4
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• pp.259-271
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• 2019

We evaluated mineralogical, physical property and accelerated weather resistance of cinnabar, realgar and orpiment used as cultural heritages and traditional paintings. JB and JS are sample names of cinnabar and JH and UH are sample names of orpiment and Realgar, respectively. As a result of mineralogical property evaluation, Jinsa was identified cinnabar (HgS) and there was no difference in chemical composition according to the grade. UH and JH were confirmed realgar (AsS) and orpiment (As₂S₃), respectively. The polarization characteristics such as shape and color indicate that pigments using our test were natural mineral pigment observed by polarization microscope. Especially, in the case of cinnabar, it is not easy to distinguish between natural mineral pigment and synthetic pigment. But the results of polarization microscope said that cinnabar is natural occurring mineral which have authentic mineral particle and unevenly fracture. As a result of thermal analysis, JH has a higher glass transition temperature and heat stability than UH. After accelerated weather test, cinnabar, realgar and orpiment were striking result in color change because of light degradation. Red color of cinnabar turn into black and the color of realgar and orpiment became brighter than before. JB (meta-cinnabar) is more photosensitivity and faster becoming dark than JB (cinnabar). Finally light transforms realgar (red, As₄S₄) in arsenolite (As₂O₃).

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.13 no.2
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• pp.67-73
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• 2007

A respiration rate analysed by enzyme kinetics-based respiration model and gas permeability data of LDPE film were applied to design the optical modified atmosphere (MA) packaging condition of persimmon (Diospyros kaki cv. Fuyu) fruits. The fruit quality rapidly decreases due to physiology disorder such as softening and peel blackening. $O_2$ permeance ($Q_{O2}$ in $ml{\cdot}hr^{-1}{\cdot}atm^{-1}{\cdot}m^{-2}$) and $CO_2$ performance ($Q_{CO2}$ in $ml{\cdot}hr^{-1}{\cdot}atm^{-1}{\cdot}m^{-2}$) of low density polyethylene (LDPE) film samples were measured at $0^{\circ}C$ and described as function of thickness (L in ${\mu}m$) as $Q_{O2}=(2540{\times}1/L)-16$, and $Q_{CO2}=(13742{\times}1/L)-70$, respectively. MA package containing single persimmon fruit of 225g was designed and tested experimentally at $0^{\circ}C$ by using LDPE films. Package atmospheres predicted from the relationship of $O_2$, $CO_2$ and $N_2$ balances on the packages was in good agreement with those obtained experimentally. Physiology disorder occurrence was the lowest at 52 ${\mu}m$ package that attained optimum gas condition ($O_2$ 2.8% and $CO_2$ 5.4%). The computer simulation was found to be effective to help to design the optimum MA packaging condition of individual persimmon fruit.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.16 no.2_3
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• pp.53-58
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• 2010

Internal gas composition of single unit persimmon package was evaluated at $-1^{\circ}C$ as function of package film area and fruit weight in order to find packaging conditions to achieve the optimal modified atmosphere beneficial for keeping the freshness. With large fruit size(${\approx}230\;g$), low permeable films (LLDPE/PP in 35 or $40\;{\mu}m$ thickness and $30\;{\mu}m$ OPP) with an exact fitness to the fruit (surface area of $0.040\;m^2$) resulted in anaerobic atmosphere with occurrence of browning in long term storage. With medium (${\approx}210\;g$) and medium small (${\approx}190g$) sizes, larger surface area of low permeable $35\;{\mu}m$ LLDPE/PP film provided higher $O_2$ and lower $CO_2$ concentrations causing higher occurrence of softening and blackening discoloration. On the other hand, smaller surface area of lower $O_2$ and higher $CO_2$ concentrations had a high risk of browning. Wise combination of fruit size, packaging film and surface area is required for attaining the beneficial modified atmosphere to prevent the physiological injuries.

• Journal of Conservation Science
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• v.30 no.1
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• pp.95-101
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• 2014

Silver objects tarnish with black from reaction with sulfurous acid or hydrogen sulfide of atmospheric. Blackening of silver objects results from formation of silver sulfide($Ag_2O$) on the surface. Silver sulfide usually is usually removed by conservation treatment. There are several cleaning methods such as chemical, electrochemical and micro-abrasion cleaning, but all of them consume silver. This study investigated the safe and effective parameter of laser cleaning by test on silver coupons. Laser cleaning is a selective process for the removal of specific substances. At first, laser cleaning applied to plain silver coupons, which were not corroded, to find out the safe range of laser energy density. From results, plain silver coupons were not changed at 1064nm below $4.00J/cm^2$ and at 532nm below $2.39J/cm^2$. The corrosion layer(silver sulfide) of artifical corroded silver coupons was removed at 1064nm with $2.39J/cm^2$ by 5~10 pulses and at 532nm with $1.19J/cm^2$ by 5~10 pulses. The removal thickness of corrosion layer was about 13-25nm per a laser pulse using AES analysis. In addition, laser cleaning tested the tarnish silver rings based on the results of silver coupons. As a result of test, the black surface were clean successfully and gave luster of silver, which showed the application possibility of laser cleaning for silver objects.

• Analytical Science and Technology
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• v.30 no.6
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• pp.312-318
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• 2017

The shelf life of 1,2-indandione/zinc (1,2-IND/Zn) solution and polyvinylpyrrolidone (PVP) solution, which are known as reagents for developing latent fingermarks deposited on the surface of thermal paper, was studied. The standard latent fingermarks used for comparisons were artificial latent fingermarks printed on thermally sensitive and non-sensitive surfaces with the same intensity. Upon treatment of standard latent fingermarks with the pre-mixed 1,2-IND/Zn and PVP solutions, the fingermarks could be successfully developed until 3 days after the preparation of the mixture. However, from the third day after mixing the reagents, blackening was observed on the surface of the thermal paper, indicating deterioration of the reagent performance. The 1,2-IND/Zn and PVP solutions separately stored without mixing in advance were mixed immediately before use, and the development efficiency of the latent fingermarks deposited on the surface of thermal paper was observed. The performance of the PVP solution decreased after 20 days from the preparation of the reagent. It was also found that the shelf life of 1,2-IND/Zn and PVP mixture was determined by the PVP solution. The effect of oxygen and moisture on the degradation of PVP was investigated. It was found that the performance of the PVP solution deteriorated because of the influence of moisture, though it was not affected by oxygen.

• 한국문화재보존과학회:학술대회논문집
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• 2004.10a
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• pp.115-130
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• 2004

Plant-based cultural assets using straw and grass as household goods of our people's have been used as indispensable tools for practical living for a very long time. However, only a limited number of artifacts were unearthed so far due to tile fragility of the material. For this reason, research on plant-based cultural properties had close to no progress, and the appropriateness of the PEG method, high-grade alcohol method, alcohol--ether-resin method, and Paraloid B-72 used in preserving plant-based cultural properties has not been sufficiently investigated. Therefore, this study examined the weight change rate by applying the methods of Primal MC-76 and vacuum freeze-drying used mostly as a earth-layer hardening material among PEG and acrylic resin, which are applied widely for preservation of waterlogged archaeological wood, as a means to preserve plant-based cultural properties along with the examination of the subject material, and an experiment was also performed on moisture absorption. The findings as a result were, first, the plant-based material being studied was found to be Typha (Typha orientalis Presl). Secondly, the weight change experiment applying $PEG\#400$ and $PEG\#4000$ confirmed a steady increase of weight if PEG -2Step is used for treatment. Third, in preserving all subject materials with soil, treatment with $PEG\#4000$, Primal MC-76, and vacuum freeze-drying showed that tile vacuum freeze-drying method resulted in the largest or $20\%$ reduction in weight, while Primal MC-76 resulted in $18\%$ and $PEG\#4000$ in $8\%$ of weight reduction. It was concluded that, considering the stability of soil measurement, this came to be because resin permeation was carried out along with tile drying process. Fourth, the weight changes were found to be around $10\%$ in various humidity conditions after the preservation treatment. The greatest weight change rate was seen in the case of $PEG\#4000$, particularly having chemicals gush out in a high humidity (RH $84\%$ or higher) environment. In the case of Primal MC-76 and vacuum freeze-drying methods, $6\~8\%$ weight changes were detected, and the lowest weight change was found in the case of the vacuum freeze-drying method. Fifth, as for color changes after treatment, blackening occurred most strongly with $PEG\#4000$, while Primal MC-76 and vacuum freeze-drying manifested colors closest to dry straw or grass. However, the texture of straw was not very evident in the case of Primal MC-76, due to a glossy surface, but vacuum freeze-drying was found to offer tile best result in terms of texture. Putting together the results of the above experiments, vacuum freeze-drying presented after being treated with PEG2-Step the most stabilized changes in weight, while it offered the smallest change in color as well.