• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.1
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• pp.200-214
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• 1993

This paper presents the results of fluidelastic instability analysis performed for the U-tube bundle of a Westinghouse model 51 steam generator, one of the recirculating types designed at an early stage, in which the principal region of external cross-flow is associated with the U-bend portion of tube. The prerequisites for this analysis are detailed informations of the secondary side flow conditions in the steam generator and the free vibration behaviours of the U-tubes. In this study, the three-dimensional two-phase flow field in the steam generator has been calculated employing the ATHOS3 steam generator two-phase flow code and the ANSYS engineering analysis code has been used to calculate the free vibration responses of specific U tubes under consideration. The assessment of the potential instability for the suspect U-tubes, which is the final analysis process of the present work, has been accomplished by combining the secondary side velocity and density distributions obtained from the ATHOS3 prediction with the relative modal displacement and natural frequency data calculated using the ANSYS code. The damping of tubes in two-phase flow has been deduced from the existing experimental data by taking into account the secondary side void fraction effect. In operation of the steam generator, the tube support conditions at the tube-to-tube support plate intersections due to either tube denting degradation or deposition of tube support plate corrosion products or ingression of dregs. Thus, various hypothetical cases regarding the tube support conditions at the tube-to-tube support plate intersections have been considered to investigate the clamped support effects on the forced vibration response of the tube. Also, the effect of anti-vibration bars support in the curved portion of tube has been examined.

• Journal of Life Science
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• v.30 no.7
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• pp.581-591
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• 2020

This study investigated the probiotic properties and physiological activities of Korean fermented foods such as sikhae, young radish kimchi, and bean-curd dregs. Among the isolated lactic acid bacteria, Pediococcus inopinatus BZ4, Lactobacillus plantarum SH1, Lactobacillus brevis SH14, Pediococcus pentosaceus YMT1, and Leuconostoc mesenteroides YMT6 demonstrated a greater than 60% survival rate at pH 2.5, along with an excellent survival rate even at 0.3% bile acid. These five bacteria showed strong flocculation ability in autoaggregation and coaggregation tests, indirectly clustering useful micro-organisms and inhibiting the attachment of pathogenic bacteria. In a cell surface hydrophobicity test, these bacteria showed adhesion to three solvents (ethyl acetate, chloroform, and xylene) and high hydrophobicity, thereby indicating excellent indirect cell adhesion to intestinal cells. The cell-free supernatants and intracellular extracts of the five lactic acid bacteria showed antioxidative activity in the form of 2,2-Diphenyl-1-picrylhydrazyl and 2,2'-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging ability and lipid peroxidation inhibition. Antimicrobial activities were also observed in four pathogenic bacteria, namely E. coli KCTC 2571, H. pylori HPKCTC B0150, L. monocytogenes KCTC 13064, and S. aureus KCTC 1916. These results demonstrate that these five lactic acid bacteria could be used as probiotics with antioxidant and antimicrobial properties.

• Food Science and Preservation
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• v.22 no.5
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• pp.714-720
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• 2015

Biji is a tofu by-product made by squeezing the liquid out of the dregs left over from making tofu. The objectives of this research were to break the biji into sub-micron-scale particles and to prepare a biji sub-micron suspension having increased quality characteristics such as antioxidant capacity, polyphenol, dietary fiber, and soluble protein contents, in comparison with untreated biji. Disruption of biji by an ultra-high-pressure homogenization (UHPH) process was used to prepare the sub-micron suspension of biji. UHPH can be used to prepare emulsions or suspensions with extremely small particle sizes. The effect of the UHPH process on biji was studied at 1,000, 1,500, and 2,000 bar. The extraction yield increased up to 1.64 times by breaking the biji to form a sub-micron suspension. The soluble dietary fiber, protein, and free amino acid contents were increased by the UHPH process (p<0.05), in comparison with those of untreated biji. Furthermore, the total sugar, free sugar, and total polyphenol contents of biji were augmented by the UHPH process. Antioxidant activity (ABTS) after exposure to UHPH (1,000-2,000 bar) was well retained (p<0.05). The extraction efficiencies and nutritive components were enhanced by increasing the pressure in the UHPH process.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.3
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• pp.605-610
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• 2003

According to the Leukemia and Lymphoma Society, leukemia is a malignant disease (cancer) that originates in a cell in the marrow. It is characterized by the uncontrolled growth of developing marrow cells. There are two major classifications of leukemia: myelogenous or lymphocytic, which can each be acute or chronic. The terms myelogenous or lymphocytic denote the cell type involved. Thus, four major types of leukemia are: acute or chronic myelogenous leukemia and acute or chronic lymphocytic leukemia. Leukemia, lymphoma and myeloma are considered to be related cancers because they involve the uncontrolled growth of cells with similar functions and origins. The diseases result from an acquired (not inherited) genetic injury to the DNA of a single cell, which becomes abnormal (malignant) and multiplies continuously. In the United States, about 2,000 children and 27,000 adults are diagnosed each year with leukemia. Treatment for cancer may include one or more of the following: chemotherapy, radiation therapy, biological therapy, surgery and bone marrow transplantation. The most effective treatment for leukemia is chemotherapy, which may involve one or a combination of anticancer drugs that destroy cancer cells. Specific types of leukemia are sometimes treated with radiation therapy or biological therapy. Common side effects of most chemotherapy drugs include hair loss, nausea and vomiting, decreased blood counts and infections. Each type of leukemia is sensitive to different combinations of chemotherapy. Medications and length of treatment vary from person to person. Treatment time is usually from one to two years. During this time, your care is managed on an outpatient basis at M. D. Anderson Cancer Center or through your local doctor. Once your protocol is determined, you will receive more specific information about the drug(s) that Will be used to treat your leukemia. There are many factors that will determine the course of treatment, including age, general health, the specific type of leukemia, and also whether there has been previous treatment. there is considerable interest among basic and clinical researchers in novel drugs with activity against leukemia. the vast history of experience of traditional oriental medicine with medicinal plants may facilitate the identification of novel anti leukemic compounds. In the present investigation, we studied 31 kinds of anti leukemic medicinal plants, which its pharmacological action was already reported through many experimental articles and oriental medical book: 『pharmacological action and application of anticancer traditional chinese medicine』 In summary: Used leukemia cellline are HL60, HL-60, Jurkat, Molt-4 of human, and P388, L-1210, L615, L-210, EL-4 of mouse. 31 kinds of anti leukemic medicinal plants are Panax ginseng C.A Mey; Polygonum cuspidatum Sieb. et Zucc; Daphne genkwa Sieb. et Zucc; Aloe ferox Mill; Phorboc diester; Tripterygium wilfordii Hook .f.; Lycoris radiata (L Her)Herb; Atractylodes macrocephala Koidz; Lilium brownii F.E. Brown Var; Paeonia suffruticosa Andr.; Angelica sinensis (Oliv.) Diels; Asparagus cochinensis (Lour. )Merr; Isatis tinctoria L.; Leonurus heterophyllus Sweet; Phytolacca acinosa Roxb.; Trichosanthes kirilowii Maxim; Dioscorea opposita Thumb; Schisandra chinensis (Rurcz. )Baill.; Auium Sativum L; Isatis tinctoria, L; Ligustisum Chvanxiong Hort; Glycyrrhiza uralensis Fisch; Euphorbia Kansui Liou; Polygala tenuifolia Willd; Evodia rutaecarpa (Juss.) Benth; Chelidonium majus L; Rumax madaeo Mak; Sophora Subprostmousea Chunet T.ehen; Strychnos mux-vomical; Acanthopanax senticosus (Rupr.et Maxim.)Harms; Rubia cordifolia L. Anti leukemic compounds, which were isolated from medicinal plants are ginsenoside Ro, ginsenoside Rh2, Emodin, Yuanhuacine, Aleemodin, phorbocdiester, Triptolide, Homolycorine, Atractylol, Colchicnamile, Paeonol, Aspargus polysaccharide A.B.C.D, Indirubin, Leonunrine, Acinosohic acid, Trichosanthin, Ge 132, Schizandrin, allicin, Indirubin, cmdiumlactone chuanxiongol, 18A glycyrrhetic acid, Kansuiphorin A 13 oxyingenol Kansuiphorin B. These investigation suggest that it may be very useful for developing more effective anti leukemic new dregs from medicinal plants.

• The Korean Journal of Mycology
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• v.31 no.3
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• pp.192-199
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• 2003

This study was carried out to investigate the artificial cultivation of Pleurotus eryngii on the optimal medium vessel, periods of cultivation and the optimal method of pinheading for both yield and quality of fruiting body were also performed. The optimal composition of sawdust medium in polypropylene(PP) bottle was combination of sawdust(70%) and corncob(30%) but increased amount of corncob delayed the period of mycelial growth. The mycelial growth and the yield of fruiting body in the medium with beat pulp were worse than that without beat pulp. The optimal composition of nutrients for both yield and quality of fruit body tuned out to be a combination of rice bran(12%), wheat bran(12%) and cottonseed cake(6%). Additions of zeolite, shell lime and bean curd dregs were not effective in mycelial growth and yield of fruit body. When testing size of PP bottle for cultivation, the larger of bottle mouth is, the more pinheading number found, but the number of available fruit body is not significantly different. The culture in $1100\;ml-{\phi}75\;mm$ bottle is the best in the yield and quality of fruit body than those in $555\;ml-{\phi}50\;mm,\;850\;ml-{\phi}58\;mm,\;850\;ml-{\phi}65\;mm\;and\;1100\;ml-{\phi}65\;mm$ bottle. Using the PP bag for cultivation, a square shaped bag was better than a round shaped and black square shaped in mycelial growth and yield of fruit body. The most suitable period of incubation was 35 days after inoculation at $22{\pm}2^{\circ}C$. When the incubation periods was decreased less than 35 days, the pileus formation and yields were very bad but a pinheading condition looked similar, For an optimal pinheading, turning upside down was better than standing and covering.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.1
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• pp.1-13
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• 2006

A field survey on the spatio-temporal distribution characteristics and origins of organic matter in surface sediments was carried out monthly at six stations in Gamak Bay, South Korea from April 2000 to March 2002. The range of ignition loss(IL) was $4.6{\sim}11.6%(7.1{\pm}1.6%)$, while chemical oxygen demand(CODs) ranged from $12.25{\sim}99.26mgO_2/g-dry(30.98{\pm}19.09mgO_2/g-dry)$, acid volatile sulfide(AVS) went from no detection(ND)${\sim}10.29mgS/g-dry(1.02{\pm}0.58mgS/g-dry)$, and phaeopigment was $6.84{\sim}116.18{\mu}g/g-dry(23.72{\pm}21.16{\mu}g/g-dry)$. The ranges of particulate organic carbon(POC) and particulate organic nitrogen(PON) were $5.45{\sim}23.24 mgC/g-dty(10.34{\pm}4.40C\;mgC/g-dry)$ and $0.71{\sim}2.99mgN/g-dry(1.37{\pm}0.58mgN/g-dry)$, respectively. Water content was in the range of $43.1{\sim}77.6%(55.8{\pm}5.6%)$, and mud content(silt+clay) was higher than 95% at all stations. The spatial distribution of organic matter in surface sediments was greatly divided between the northwestern, central and eastern areas, southern entrance area from the distribution characteristic of their organic matters. The concentrations of almost all items were greater at the northwestern and southern entrance area than at the other areas in Gamak Bay. In particular, sedimentary pollution was very serious at the northwestern area, because the area had an excessive supply of organic matter due to aquaculture activity and the inflow of sewage from the land. These materials stayed longer because of the topographical characteristics of such as basin and the anoxic conditions in the bottom seawater environment caused by thermocline in the summer. The tendency of temporal change was most prominently in the period of high-water temperatures than low-water ones at the northwestern and southern entrance areas. On the other hand, the central and eastern areas did not show a regular trend for changing the concentrations of each item but mainly showed a higher tendency during the low-water temperatures. This was observed for all but AVS concentrations which were higher during the period of high-water temperature at all stations. Especially, the central and eastern areas showed a large temporal increase of AVS concentration during those periods of high-water temperature where the concentration of CODs was in excess of $20mgO_2/g-dry$. The results show that the organic matters in surface sediments in Gamak Bay actually originated from autochthonous organic matters with eight or less in average C/N ratio including the organic matters generated by the use of ocean, rather than terrigenous organic matters. However, the formation of autochthonous organic matter was mainly derived from detritus than living phytoplankton, indicated the results of the POC/phaeopigment ratio. In addition, the CODs/IL ratio results demonstrate that the detritus was the product of artificial activities such as dregs feeding and fecal pellets of farm organisms caused by aquaculture activities rather than the dynamic of natural ocean activities.