• 치과방사선
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• 제26권2호
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• pp.45-63
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• 1996

In attempt to determine radiation effect on the mandibular condyle of the growing rat, 27 white female rats (Sprague-Dawley) were divided into 3 groups and irradiated respectively 5Gy, 10Gy, 20Gy using MK Cell Irradiator. Mandibular condyles from rats on the day of 1, 7, 14 after the irradiation day were obtained, sectioned sagittally and examined by light microscopy, and thereafter middle portion through anteroposterior direction on the sagittal plane was selected to examine the ultrastructural change by transmission electron microscopy. The obtained results are followings. 1. In the proliferative zone some cells showed little organelles in case of 5Gy irradiation, in addition the number of degenerative cells increased and in case of 10Gy irradiation, and in case of 20 Gy irradiation total number of cells decreased. 2. In the hypertrophic zone, narrowing of width and partial disorder in hypertrophic process were noted in case of 5 Gy irradiation, and more prominent narrowing of width and more irregular disorder in hypertrophic process in case of both 10Gy and 20Gy irradiation. 3. In the upper hypertrophic zone some chondrocytes seemed to be dying and the polarity of nuclei could not be seen, if any. 4. The periodic observation showed the severest change at day 7 and the signs of recovery at day 14 after irradiation.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권5호
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• pp.39-45
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• 2013

Many researchers have studied the effectiveness of ultrasound in chemical and environmental engineering fields including material synthesis, pollutant removal, cleaning, extraction, and disinfection. Acoustic cavitation induced by ultrasound irradiation in aqueous phase can cause various sonophysical and sonochemical reactions without any chemicals. However most of the previous studies focused only on the relationships between ultrasonic conditions and the results of sonochemical reactions in lab-scale sonoreactors. As a results of this, only a few studies have been devoted to design and optimization of industrial scale sonoreactors. In this study, the effect of the distance between two opposite transducer modules on sonochemical reactions was investigated in single and dual irradiation systems (334 kHz) for four distances including 50, 100, 150, and 200 mm using KI dosimetry. It was found that the dual irradiation systems provided higher performance in terms of the zeroth reaction coefficient and the cavitation yield compared to the single irradiation systems. The sonochemiluminescence (SCL) images for the visualization of the cavitation field showed that cavitation active zone was larger and sonochemical reaction intensity was much higher in the dual irradiation system than in the single irradiation system.

• Nuclear Engineering and Technology
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• 제55권3호
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• pp.958-967
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• 2023

This work studies the defect features in a dilute FeMnNi alloy by an Object Kinetic Monte Carlo (OKMC) model based on the "grey-alloy" method. The dose rate effect is studied at 573 K in a wide range of dose rates from 10^-8 to 10^-4 displacement per atom (dpa)/s and demonstrates that the density of defect clusters rises while the average size of defect clusters decreases with increasing dose rate. However, the dose-rate effect decreases with increasing irradiation dose. The model considered two realistic mechanisms for producing <100>-type self-interstitial atom (SIA) loops and gave reasonable production ratios compared with experimental results. Our simulation shows that the proportion of <100>-type SIA loops could change obviously with the dose rate, influencing hardening prediction for various dose rates irradiation. We also investigated ways to compensate for the dose rate effect. The simulation results verified that about a 100 K temperature shift at a high dose rate of 1×10^-4 dpa/s could produce similar irradiation microstructures to a lower dose rate of 1×10^-7 dpa/s irradiation, including matrix defects and deduced solute migration events. The work brings new insight into the OKMC modeling and the dose rate effect of the Fe-based alloys.

• KSBB Journal
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• 제27권4호
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• pp.222-226
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• 2012

In this study, the effect of gamma irradiation on the microbial contamination and biological activities of tuna cooking juices was investigated. Tuna cooking juice was by-produced during the canning processing, and had various functional components. But, it was shown that the tuna cooking juice was seriously contaminated. Gamma irradiation effectively reduced the microbial population in tuna cooking juice. Also, 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity, tyrosinse inhibitory activity, and ACE inhibitory activity of tuna cooking juices were all increased as a result of gamma irradiation. These results suggest that wasted tuna cooking juices can be used as a functional component in the food and cosmetic industries if the irradiation technology were applied.

• 대한한의학회지
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• 제26권4호
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• pp.143-151
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• 2005

Objectives: The purpose of this study was to investigate the effect of exterior vascular laser irradiation therapy by live blood analysis. Methods: We analysed the changing forms of the live blood sample with a microscope before and after exterior vascular laser irradiation therapy of the blood. Results: Rouleau of red cells, erythrocyte aggregation of red cells, thrombocyte aggregation, uric acid crystals, red crystals, and protoplasts in blood were decreased significantly after exterior vascular laser irradiation therapy. Conclusions: This study suggests that exterior vascular laser irradiation will have positive effects in eliminating various effete matters in blood and will have efficacy in the treatment and prevention of cardiovascular system disorders and hyperlipidemia, caused by effete matters, or numbness and arthralgia caused by blood stagnancy and blood circulation disorder.

• Journal of Ginseng Research
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• 제17권1호
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• pp.29-34
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• 1993

This study was undertaken to investigate the effect of red ginseng extract (5.5 mg/mouse ip) on the activities of superoxide dismutase (SOD), peroxidase and catalase in the liver of the gamma ray irradiated male mice. The experimental groups consisted of control, red ginseng extract injection group, irradiation (8 $Gy^{60}$Co) group and red ginseng extract injection after irradiation group. in red ginseng extract injection group, SOD, peroxidase and catalase activities were similar to that in the control group. In irradiation group SOD, peroxidase and catalase activities increased progressively until the 2nd day after the treatment and then decreased thereafter, whereas red ginseng extract injection after irradiation group recovered more rapidly than irradiation group. The above results suggested that red ginseng extract injection after irradiation group have the recovery effects on the activities of SOD, peroxidase and catalase after radiation injury in the liver of male mice.

• 대한한방내과학회지
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• 제27권2호
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• pp.316-326
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• 2006

Backgrounds & Objects: The aim of this study was to investigate the radioprotective effect of Shengmai-san(SMS), a herbal medicine, on mice jejunal crypt cell survival and Apoptosis. Methods: Mice were devided into 4 groups according to radiation dose and SMS treatment: Normal was the group without irradiation. Control was the group treated with D.W before 10 Gy irradiation. SMS 2.9 was sample group treated with 2.9 mg/10 g of SMS extract before 10 Gy irradiation and SMS 29 was sample group treated with 29 mg/10 g of SMS extract before 10 Gy irradiation. And Each group were sacrificedat 24 hours and 72 hours after irradiation. To analyze the crypt survival, hematoxylin-eosin staining was used and to analyze the apoptosis, the TUNEL assay was done. Results: 1. From the microcolony survival assay, the SMS 2.9 and SMS 29 showed the radioprotective effect with a statistical significance compared to the control group at 24 hr (P < 0.01) and 72 hr (p < 0.001) after 10 Gy irradiatien. And the differences of radioprotective effect between SMS 2.9 and SMS 29 were net significant. 2. The results of the TUNEL assay showed that the apoptotic index in SMS 2.9 and SMS 29 was significantly decreased, as compared to the control group at both 24 hr ( p < 0.01) and 72 hr (SMS 2.9 : p < 0.001. SMS 29 : P < 0.01) after 10Gy irradiation And the differences of between SMS 2.9 and SMS 29 were not significant. Conclusions: It could be suggested that the Shengmai-san has a prominent Protective effect in mice intestines against the radiation damage. And the radieprotective effect seems to be related to inhibition of the apoptosis.

• 치과방사선
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• 제8권1호
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• pp.39-42
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• 1978

The effect of irradiation of x-ray to developing rat mandible in the gestation stage was focused on the study of mandible development and the side effect of x-ray irradiation. The author studied the effect of x-ray irradiation with the gestated rat and their off'springs. 100 rads, 200 rads, 300 rads and 400 rads of x-ray was irradiated in regular order schematically at the lower left abdomen of gestated rat. 18½days after conception, their off'springs were sacrificed and exaimined their developing mandible with histological findings. The results were as followed. 1. In the 100-200 rads irradiated rat off'springs, bony trabeclulation was revealed irregular shape. In combine with this finding, osteoblast and fibroblast were appeared shrunken of their nucleus and location of eccentric position. 2. In the 300-400 rads irradiated rat off'springs, decrease of fibroblast and osteoblast appearance in the periosteum were prominently observed and empty lacunae were frequently appeared in their bone matrix. 3. The advent of osteoclast and resorption of cortical bone were appeared in proportion to increasing of x-ray irradiation.

• Nuclear Engineering and Technology
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• 제53권5호
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• pp.1602-1611
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• 2021

A varying degree of eccentricity always exists in the initial configuration of a nuclear fuel rod. Its impact on traditional LWR fuel is limited as the radial gap closes relatively early during irradiation. However, the effect of misalignment is expected to be more relevant in rods with highly conductive fuels, large initial gaps and low conductivity filling gases. In this paper, we study similar characteristics in the experimental setup of two fuel disc irradiation campaigns carried out in the OECD Halden Boiling Water Reactor. Using the multi-dimensional fuel performance code OFFBEAT, we combine 2-D axisymmetric and 3-D simulations to investigate the effect of eccentricity on the fuel temperature distribution. At the same time, we illustrate how the advent of modern tools with multi-dimensional capabilities might further improve the design and interpretation of in-pile separate-effect tests and we outline the potential of such an analysis for upcoming experiments.

• 한국의류산업학회지
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• 제15권3호
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• pp.430-436
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• 2013

The purpose of this study investigates the effects of electron beam(EB) irradiation on the chemical and morphological properties of Hansan ramie fiber. Hansan ramie fibers were irradiated with electron beam doses of 0, 1, 3, 5 and 10kGy. The effect of electron beam irradiation on the chemical components of fibers as well as the surface chemical and morphological properties were investigated using chemical component analysis methods based on TAPPI standards, XPS, and SEM. The results indicate that the surface layers can be removed under suitable EB irradiation doses. Alcohol-benzene extraction and lignin content increases gradually with an increase in EB irradiation and reaching a maximum at an EB dose of 3kGy, and decreases at 10kGy. The surface chemical changes measured by XPS corresponded to the chemical composition analysis results. The C1 peak and the O/C ratio decreased with the removal of the multi-layer and primary layer by EB irradiation. The SEM images show the inter-fibrillar structure etched by EB irradiation up to 5kGy. At 10kGy, the surface structure of the ramie fiber shows highly aligned and distinctive striations in a longitudinal direction. The removal of these exterior layers of the fiber was confirmed by changes in surface morphology as observed in SEM images.