• Korean Journal of Microbiology
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• v.28 no.1
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• pp.55-64
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• 1990

Cell volume and DNA contents of the fusants were similar to those of parents. Genetic stability of the fusants was increased when they were cultured on minimal medium (MM) rather than on complete medium (CM), and the fusants were stabilized by subculturing 7 generations each 7 day on MM agar. The finally selected fusants after being cultured for 6 months on CM were stable without segregation. The fusants could also form nuclein and ascospores, and show red and pink colors by the test of TTC colorization. Assimilability and fermentability of carbon sources of the fusants were similarto those of parents. The tolerance of KCl, NaCl, sodium propionate and cycloheximide showed the traits of one strain of parents. When the fusants were cultured for 72 hr and 60 hr in the medium containing 20% glucose and sucrose, respectively, the yield of ethanol for FWKS 260 was reached to 9.6 v/v% and 9.8v/v%, respectively. The sensitive strain Kyokai 7 was found to be killed entirely after cultivation of 48 hr by the killer toxin from the fusants. The recipient S 29 and Kyokai 7 were found to have neither L nor M dsRNA plasmid. However, K 52 and fusants had both L and M dsRNA plasmid of 4.7 kb and 2.5 kb, respectively. The curants treated by heat and cycloheximide did not contain M dsRNA plasmid, but had large amounts of L dsRNA plasmid of those of killer yeasts.

• Korean Journal of Heritage: History & Science
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• v.54 no.1
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• pp.18-31
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• 2021

Linoleum is a resilient, hygienic, and eco-friendly floor covering. It was developed in England by Frederick Walton in 1863. Made of cork flour, linseed oil, and burlap as its main materials, the flexible and waterproof linoleum became globally popular in the early 20th century. Unlike the vinyl coverings, the burlap-backed linoleum was used not only in commercial spaces but also in household areas like kitchens, bathrooms, and even living rooms. As a global product, linoleum was imported and used in Korean palaces like Deoksugung and Changdeokgung in the early modern period. According to the record Deoksugung Won-Ahn, linoleum was applied to the major buildings, including Hamnyeongjeon, Deokhongjeon, and Jeonggwanheon, and various other venues. The linoleum used in these places are mainly monochrome blue and brown color, which probably means that they are from England. The trade records in the early 20th century show that linoleum was imported mainly from England and America. The Ewangjik building floor plan in the Changdeokgung Palace shows that linoleum was used extensively. There are even some originals, which were laid in 1920 and left in the Changdeokgung Palace. When Daejojeon and Huijeongdang were rebuilt in 1920, the interior was outfitted with western features and linoleum was used in areas such as bathrooms, the tonsorial parlor, and one of the rooms on the west side of Huijeongdang. In situ in the Daejojeon and Huijeongdang areas in the Changdeokgung Palace are monochrome, patterned black, and stylized floral tile patterned, which are closely similar to American products made by ALC and Armstrong company. This study will help us better understand linoleum's characteristics, its uses and the material itself. It will also form the basis for the restoration of Changdeokgung Palace as well as other modern interiors with linoleum flooring in the future.

• Journal of the Korean Wood Science and Technology
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• v.40 no.3
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• pp.164-176
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• 2012

In the present study, rapeseed flour (RSF), which is a by-product from the production of edible oil and biodiesel extracted from rapeseed, was used to develop alternative adhesives for the production of plywood panels. To examine the effects of the enzyme on the adhesive properties and formaldehyde emission of the RSF-based adhesive resins, three enzymes, such as cellulase (CEL), pectinase (PEC) and protease (ALC), were used either separately or together. As a crosslinking agent, PF prepolymers, which were prepared with 1.5, 1.8 and 2.1 mole formaldehyde and 1 mol phenol (1.8-, 2.1- and 2.4-PF), were added into the RSF hydrolyzates. The adhesive resins formulated with CEL- or CEL-PEC-RSF hydrolyzates and 1.8-F/P PF prepolymers exhibited excellent adhesive strengths and formaldehyde emission. The tensile shear strength and formaldehyde emission of the plywood panels bonded with the formulate resins were satisfied with the minimum requirement of the KS standard for ordinary plywood panels (0.6 N/$mm^2$). In addition, formaldehyde emissions of the plywood panels approached to that of E0 specified in the KS standard (0.5 mg/${\ell}$), and even had much better than those of commercial UF glue mixes. Overall, the use of RSF-based adhesive resins for the production of plywood panels might provide durable adhesive properties and an environmentally friendly substitute for petroleum-based adhesive resins. However, further researches - the increase of solid content of RSF-based adhesives for reducing press time and the microscopic observation of plywood specimen for identifying the relationship between tensile shear strength and the penetration of adhesives into wood structure - are required to commercialize the RSF-based adhesives.

• The Korean Journal of Nuclear Medicine
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• v.34 no.1
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• pp.55-61
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• 2000

Purpose: We performed this study to evaluate the changes of gallbladder ejection fraction (GBEF) in diabetic patients with or without autonomic neuropathy. Materials and Methods: This study included 37 diabetic patients (25 women, 12 men, mean age 51 years) and 24 normal controls (10 women, 14 men, mean age 38 years). After intravenous injection of 185 MBq of $^{99m}Tc$-DISIDA, serial anterior abdominal images were acquired before and after fatty meal. Regions of interest were applied on gallbladder and right hepatic lobe on 60 and 90 minute images to calculate GBEF. Results: GBEF was significantly reduced in diabetes with autonomic neuropathy ($43{\pm}12.3%$) and without autonomic neuropathy ($57.5{\pm}13.2%$) compared with normal controls ($68{\pm}11.6%$, p<0.05). And also, GBEF was significantly reduced in diabetes with autonomic neuropathy compared with diabetes without autonomic neuropathy (p<0.05). Fasting blood glucose level, age, sex, hemoglobin Alc, body mass index, serum lipid level were not different in these two diabetic patient groups (p>0.05). When 50.2% of GBEF was used as the criteria for diabetic autonomic neuropathy, the sensitivity and specificity were 80%, 76.5%, respectively. The area under receiver operating characteristic curve was 0.846. Conclusion: GBEF of diabetic patients with autonomic neuropathy was significantly reduced than that of diabetic patients without autonomic neuropathy.

• Analytical Science and Technology
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• v.9 no.3
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• pp.279-291
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• 1996

The new chelating resins, XAD-2, 4, 16-TAC and XAD-2, 4, 16-TAO were synthesized by Amberlite XAD-2, XAD-4, and XAD-16 macroreticular resins with 2-(2-thiazolylazo)-p-cresol(TAC) and 4-(2-thiazolylazo)orcinol(TAO) as functional groups and were characterized by elemental analysis and FT-IR spectrometry. It was found that the content of functional group in chelating resin was 0.60mmol/g in XAD-16-TAC and 0.68mmol/g in XAD-16-TAO respectively. The chelating resins were stable in acidic and alkaline solution and can be reused over 10 times. The sorption behavior of some metalions to two chelating resins was investigated by batch method, which included batch equilibrium, effect of pH, coexisting ions and masking agent. For the optimum condition of sorption, the time required for equilibrium was about 1 hour and optimum pH was 5. In the presence of anions such as ${SO_4}^{2-}$ and $CH_3COO^-$, the sorption of U(VI) ion was slightly reduced but other anions such as $Cl^-$ and $NO{_3}^-$ revealed no interference effect. Also, sorption capacity of U(VI) ion was decreased by addition of $CO{_3}^{2-}$ ion because of complex formation of $[UO_2(CO_3)_3]^{4-}$, but alkali metals and alkali earth metals including Na(I), K(I), Mg(II), and Ca(II) were not affected for the sorption extent. Masking agent, NTA showed better separation efficiency of U(VI) ion from coexisting metal ions such as Th(IV), Zr(IV), Hf(IV), Cu(II), Cd(II), Pb(II), Ni(II), Zn(II) and Mn(II) than EDTA, CDTA.

• The Korean Journal of Food And Nutrition
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• v.11 no.2
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• pp.243-248
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• 1998

Ark shell was known as shellfish that had hemoglobin as blood pigment and the action of mecidine, was consumed the great part of it as raw material, though it was produced about 13,000 M/T per year. Ark shell was processed the infinitesimal quantity as conned product, bout canned ark shell had problem that occurrenced discoloration after heat treatment during processing and storage. This discoloration mechanism during processing and storage was not cleared. This study was carried out to understand characteristics of the hemoglobin as blood pigment and carotenoid as meat pigment in ark shell and management of proper processing conditions for prevention of oxidation and discoloration by thermal treatment. When treated by digestion of 0.1% BHA, 0.1% Tenox-II, 0.5% Na2EDTA, 0.05% NDGA and 3% salt soln., 0.1% BHA solution was most suitable for stability of carotenoid that the retention ratio of carotenoids were 63.1% after heating to 116$^{\circ}C$ for 120 minutes. In preparation of canned ark shell and storage at 37$\pm$1$^{\circ}C$ for 60 days, the chemical composition, pH and salinity ere stable. And contents of total carotenoid were decreased slightly from 0.83mg% to 0.727mg%. The viable cell count were 6.92$\times$103 cfu/ml at raw ark shell, after processed and storage were not detected. The predominant amino acids in the raw ark shell were glutamic acid(19.7%), arginine(16.0%), glycine(12.6%), alanine(12.2%) and aspartic acid(7.6%). When 60 days stored, the contents of amino acid were stable. And the predominant nuclotide and their related compounds in the raw ark shell were hypoxanthine(2.14$\mu$mol/g), IMP(1.94$\mu$mol/g) and ATP(0.87$\mu$mol/g), and storage at 37$\pm$1$^{\circ}C$ for 60 days, the quantity order were same as raw material.

• Journal of the Korea Institute of Building Construction
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• v.9 no.4
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• pp.63-73
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• 2009

Recently, the use of lightweight panels in building structures has been increasing. Of the various lightweight panel types, styrofoam sandwich panels are inexpensive and are excellent in terms of their insulation capacity and their constructability. However, sandwich panels that include organic material are quite vulnerable to fire, and thus can numerous casualties in the event of a fire due to the lack of time to vacate and their emission of poisonous gas. On the other hand, lightweight foamed concrete is excellent, both in terms of its insulation ability and its fire resistance, due to its Inner pores. The properties of lightweight concrete is influenced by foaming agent type. Accordingly, this study investigates the insulation properties by foaming agent type, to evaluate the possibility of using light-weight foamed concrete instead of styrene foam. Our research found thatnon-heating zone temperature of lightweight foamed concrete using AP (Aluminum Powder) and FP (animal protein foaming agent) are lower than that of light-weight foamed concrete using AES (alkyl ether lactic acid ester). Lightweight foamed concrete using AES and FP satisfied fire performance requirements of two hours at a foam ratio 50, 100. Lightweight foamed concrete using AP satisfied fire performance requirements of two hours at AP ratio 0.1, 0.15. The insulation properties were better in closed pore foamed concrete by made AP, FP than with open pore foamed concrete made using AES.