• Clean Technology
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• v.26 no.2
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• pp.102-108
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• 2020

In recent years, packed column has been widely used in separation processes, such as absorption, desorption, distillation, and extraction, in the petrochemical, fine chemistry, and environmental industries. Packed column is used as a contacting facility for gas-liquid and liquid-liquid systems filled with random packed materials in the column. Packed column has various advantages such as low pressure drop, economical efficiency, thermally sensitive liquids, easy repairing restoration, and noxious gas treatment. The performance of a packed column is highly dependent on the maintenance of good gas and liquid distribution throughout a packed bed; thus, this is an important consideration in a design of packed column. In this study, hydraulic pressure drop, hold-up as a function of liquid load, and mass transfer in the air, air/water, and air-NH₃/water systems were studied to find the geometrical characteristic for raschig super-ring experiment dry pressure drop. Based on the results, design factors and operating conditions to handle noxious gases were obtained. The dry pressure drop of the random packing raschig super-ring was linearly increased as a function of gas capacity factor with various liquid loads in the Air/Water system. This result is lower than that of 35 mm Pall-ring, which is most commonly used in the industrial field. Also, it can be found that the hydraulic pressure drop of raschig super-ring is consistently increased by gas capacity factor with various liquid loads. When gas capacity factor with various liquid loads is increased from 1.855 to 2.323 kg^-1/2 m^-1/2 S^-1, hydraulic pressure drop increases around 17%. Finally, the liquid hold-up related to packing volume, which is a parameter of specific liquid load depending on gas capacity factor, shows consistent increase by around 3.84 kg^-1/2 m^-1/2 S^-1 of the gas capacity factor. However, liquid hold-up significantly increases above it.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.721-724
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• 2007

In this study, we examined the effects of Angelica keiskei (AK) in rats, in order to evaluate tissue quercetin concentrations and serum lipid profile changes. Dried AK powder was added to a regular chow at a 5% level, and fed for 8 weeks to male rats. AK significantly lowered serum total cholesterol, low-density lipoprotein cholesterol, and very low-density lipoprotein cholesterol levels, while it increased high-density lipoprotein cholesterol levels. However, AK did not influence serum triglyceride levels. Two antioxidant flavonoids present in AK, quercetin and its glycoside isoquercitrin, were detected in the serum and liver of the rat. However, another quercetin glycoside, hyperoside, was not detected in either the serum or liver despite its presence in the diet. These results indicate that AK seems to alter serum lipid concentrations, possibly through the body's absorption of certain quercetin glycosides.

• Journal of Life Science
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• v.25 no.1
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• pp.53-61
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• 2015

In this study, we tried to separate the photosensitizer that induces apoptosis of leukemia cells (U937) from perilla leaves. Perilla leaves (Perilla frutescens Britt var. japonica Hara) are a popular vegetable in Korea, being rich in vitamins (A and E), GABA, and minerals. Dried perilla leaves were extracted with methanol to separate the photosensitizer by various chromatographic techniques. The structure of the isolated compound (PL9443) was identified by 1D-NMR, 2D-NMR, and FAB-mass spectroscopy. Absorbance of the UV-Vis spectrum was highest at 410 nm and was confirmed by the 330, 410, and 668 nm. PL9443 compound was determined to be pheophorbide, an ethyl ester having a molecular weight of 620. It was identified as a derivative compound of pheophorbide structure when magnesium comes away from a porphyrin ring. Observation of morphological changes in U937 cells following cell death induced by treated PL9443 compound revealed representative phenomena of apoptosis only in light irradiation conditions (apoptotic body, vesicle formation). Results from examining the cytotoxicity of PL9443 substance against U937 cells showed that inhibition rates of the cell growth were 99.9% with the concentration of 0.32 nM PL9443. Also, the caspase-3/7 activity was 99% against U937 cells with the concentration of 0.08 nM of PL9443 substance. The result of the electrophoresis was that a DNA ladder was formed by the PL9443. The PL9443 compound is a promising lead compound as a photosensitizer for photodynamic therapy of cancer.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.3
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• pp.253-257
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• 1984

A field experiment was conducted in order to secure the basic information on the rational application of nitrogen and potassium for autumn growing Chinese cabbage (Brassica campastris ssp. pekinensis, var.; Miho 70 days). The results of the experiment are summarized as follows: 1. Potassium effect was observed where nitrogen applied either less than 15kg N/10a and heavy dose of 25kg N/10a. No potassium effect was observed where 20kg N/10a applied. In the case of 25kg N/10a, potassium effect was observed only in total weight but failed yield marketable product weighing over 1 kilogram per cabbage. 2. Nitrogen application, in general, tends to lower the soil pH and it is particularly true when heavy dose of over 20kg N/10a is applied. As a result, Chinese cabbage has increasingly removed soil born potassium and reduced exchangeable potassium content of the soil. 3. Oven dried cabbage which received 25kg N/10a plus potassium showed a low concentration of calcium and this phenomena seems to be attributable to the acidification of soils and it further caused failure in producing cabbages of marketing value.

• Korean Journal of Food Science and Technology
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• v.43 no.6
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• pp.729-734
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• 2011

With the goal of transforming rice protein from an insoluble to a soluble form to increase the industrial utilization of rice wine meal (RWM), RWM was derivatized using commercial proteases and the RWM hydrolysates were characterized. Eight commercial proteases were used individually or in combination for hydrolysis of RWM. The degree of hydrolysis was assessed by determining the soluble protein in supernatant using the Lowry assay, protein in precipitates using a semimicro Kjeldahl procedure, and gravimetrically by the weight difference before and after hydrolysis. Protamex, Alcalase and Protease N proteases were most effective for hydrolysis of RWM. Although these assessment methodologies displayed some variation, they generally showed a similar pattern. When the aforementioned three proteases were simultaneously used to treat RWM, no significant difference was observed between the three assays (p<0.05) indicating an absence of enzymatic synergy.

• Journal of Periodontal and Implant Science
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• v.35 no.4
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• pp.949-959
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• 2005

이 연구는 임플란트를 식립하기를 원하는 전신건강상태가 양호하며 구강위생상태가 좋은 14명 환자(남자:8명, 여자:6명, 평균나이 : 44세)의 20개의 발치와 내에 흡수성 차폐막(BioMesh. Sam Yang Corporation, Korea)과 함께 탈회냉동 건조동종 골(dem-ineralized freezedried bone allografts, $250-500{\mu}m$. Pacific Coast Tissue Bank, U.S.A.)과 이종골(Bovine-Bone, Bio-Oss 0.25-1.0 mm, Geistlich, Biomaterials and Osteohealth, Switzerland)을 1:1(부피)로 혼합하여 이식한 후 그 치유양상을 관찰하고자 조직학적 및 면역조직화학적으로 평가하였다. 이직재가 탈락되는 것을 방지하기 위하여 발치한 후 1개윌이 경과된 후에 이식재와 차폐막을 위치시켰다. 표본제작을 위하여 이식술을 시행한 지 약 6개윌 후에 임플란트를 식립하기 직전 식립부위에서 trephine bur로 골을 채취하였는데, 20증례 중 7증례에서 임플란트를 식립하기 전에 차폐막이 노출되었다. 차폐막이 노출되지 않은 것을 대조군으로, 노출된 것을 실험군으로 설정하였다. 조직학적인 관찰을 위하여 통상적인 방법에 따라 탈회 표본을 제작하였고, alkaline phosphotase(ALP)틀 이용하여 면역조직화학적 염색을 시행한 후 골 형성 상태를 평가하여 다음과 같은 결과를 얻었다. 본 연구에서는 발치와내에서 골유도재생술 후 나타나는 치유 형태를 5가지 형태로 분류할 수 있었다. Type I, II와 III는 새로운 골 형성을 나타내지 않았고, 면역조직화학적 검사 시 ALP 음성 소견을 나타내었다. Type V는 새로운 골 형성과 ALP 양성 소견을 나타내었으나 염증, 괴사, 결합조직의 증식 등은 없었다. Type IV와 Type V의 차이는 결합조직의 증식여부로 구분되었다. 막이 노출되지않은 증례들 중 7 증례에서는 Type V의 치유 형태를, 2증례에서는 Type IV의 치유 형태를 나타내었다. 막이 노출되었던 증례에서는 Type I, II, III의 다양한 치유 형태를 나타내었다. 본 연구결과, 발치와 내에 골유도재생술을 시행한 후 차폐막의 노출 여부가 신생골 형성에 중요한 영향을 미칠 것으로 사료되며, 본 연구에서 분류한 치유 형태가 향후 골유도재생술 후의 결과 분석에 활용될 수 있을 것으로 사료된다.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.4
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• pp.564-572
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• 2000

We decided among extraction, orthodontic traction and autotransplantation such as direction and position of unerupted tooth, degree of developing root apex, eruption space, being of supernumerary tooth or odontoma or cyst when tooth impacted. Autotransplantation is considered when orthodontic traction is unrealistic or when tooth movement can absorb root of neighbor tooth. The prognosis for successful autotransplantation is dependent on a number of factors such as root development, surgical technique, patient's age, endodontic treatment, time and type of splinting, preservation of periodontal ligament and storage medium. Especially when severe osseous defect is being, bone graft considered for reducing of mobility and for assisting recovery. In all cases, chief complaint is unerupted tooth and various causing factors were supernumerary, odontoma, ectopia and so on. Before autotransplantation, space regaining was done if needed and demineralized freezed dried bone and autogenous bone graft was done when there is severe osseous defect by extraction of supernumerary tooth or odontoma. Splinting was removed after 2-3weeks At 3-4weeks after autotransplantation, endodontic treatment was decided. At follow up check, normal recovery was done and there was no inflammatory or replacement root resorption in periapical radiograph.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1363-1370
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• 2006

This study was designed to evaluate the effect of Agaricus blazei $\beta-glucan$ and egg shell calcium complex on bone metabolism in ovariectomized (OVX) rats. Forty Sprague-Dewley female rats, 10 weeks of age $(248{\pm}1.7g)$, were divided into 4 groups and fed on the experimental diets for 6 weeks: sham operated control treated with normal diet containing 0.5% calcium (Sham-C), OVX-control treated with normal diet containing 0.5% calcium (OVX-C), $OVX-\beta-glucan$ group treated with $\beta-glucan$ diet containing 0.5% calcium (OVX-G), and $OVX-\beta-glucan$ egg shell calcium complex treated with $OVX-\beta-glucan$ egg shell calcium complex containing 0.5% calcium (OVX-GE). Bone weight of femur was higher in the OVX-GE group than in the other OVX groups. Bone mineral density of femur was significantly different (p<0.05) among the experimental groups and showed the highest level in the OVX-GE group. Calcium absorption rate and retention were higher in the $\beta-glucan$ supplement groups than in the other groups (p<0.05). Alkaline phosphatase activities and osteocalcin levels of serum showed lower in the $\beta-glucan$ supplement groups than in the OVX-C group. Deoxypyridinoline crosslink values of urine, indicator of bone absorption, showed the lowest in the OVX-GE group. The $\beta-glucan$ supplemented groups had a lower bone resorption ratio than in the OVX-C group. We concluded that bioavailability of calcium is higher in $\beta-glucan$ supplement groups compared to those in OVX rats. From the above results, these findings suggest the possibility of using $\beta-glucan$ egg shell calcium complex as a functional food material related to bone metabolism, even though there is no significant difference between the groups of $\beta-glucan$ and $\beta-glucan-egg$ shell calcium complex supplementation.

• Korean journal of food and cookery science
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• v.30 no.6
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• pp.670-678
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• 2014

The purpose of this study was to find the optimal swelling method and condition for seacucumber to improve its taste and texture to accomodate the rapid increase of consumption. Another purpose was to try to determine an easy way to soak dried sea-cucumber under different conditions, and identify the influence of swelling time on the texture of sea-cucumber, in order to reduce preparation time and provide basic data for easy handling. After boiling or steaming for six different periods including 5, 15, 30 and 60 minutes the texture of the sea-cucumbers were compared, For the additive test, the sea-cucumbers were boiling for 30 minutes period with 4 different additives and the textures were compared, Since the texture is an important characteristic of sea-cucumber, there are many variables that affect this property including the, drying and preservation methods. This study provides basic understanding of the influence of the heating method, time and temperature on the swelling of sea-cucumber for handy use at processing sites.

• Applied Biological Chemistry
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• v.29 no.3
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• pp.288-293
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• 1986

The washed fresh ginsengs packed with air, vaccum and nitrogen gas were irradiated at the levels of 1,2 and 3kGy gamma radiation and then stored at $4{\sim}5^{\circ}C$ for 90days to investigate the effects of gamma radiation on microbial inactivation, eelworm disinfestation and physicochemical changes. After a 90 day storage, $2{\sim}3kGy$ irradiated groups showed 20% of weight loss and 10% of rot while non-irradiated group 100% and 20% or more, respectively. Also the irradiated groups showed somewhat lower values of specific gravity, color density and hardness immediately after irradiation, thereafter higher value of them with storage time than those of non-irradiated group. The irradiation increased the yields of ginseng extract and crude saponins but no effects on the proximate composition and TLC and HPLC patterns of saponin. The food-borne microorganisms decreased in viable cell counts by $2{\sim}3$ log cycles with $2{\sim}3kGy$ radiation and the eelworms were completely disinfested with 1 kGy radiation.