• Title/Summary/Keyword: B-type

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A Comparison of Chromium and Copper-Containing Waterborne Wood Preservatives for Fixing and Leaching Characteristics (크롬-구리 화합물계(化合物系) 목재방부제(木材防腐劑)의 정착(定着) 및 용탈특성(溶脫特性) 비교(比較))

  • Ra, Jong-Bum;Kim, Gyu-Hyeok
    • Journal of the Korean Wood Science and Technology
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    • v.23 no.3
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    • pp.66-72
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    • 1995
  • The rate of fixation of the components were evaluated in CCA-Type B and CCFZ-treated radiata pine sapwood by quantitative analysis of solution expressed from the treated wood. The leaching characteristics of radiata pine blocks treated with CCA-Type B and CCFZ were also evaluated by the AWPA standard leaching test. Both fixation and leaching charactersistics of CCA-Type B were compared with CCA-Type C treated wood samples. The rate of CCA-Type B fixation was a little faster than that of CCFZ. However, significant amounts of arsenic was unfixed in the CCA-Type B treated samples and consequently leached. These significant quantities of arsenic liberated from the CCA-Type B treated wood during service may pose some environmental concerns. Arsenic was no longer detectable from CCA-Type C treated samples when fixation was complete, even though the fixation of CCA-Type C was slower in some degree than CCA-Type B. In summary, it could be said that CCFZ was much safer preservative than CCA-Type B by the criterion based on the relative hazard assessed by absolute amount of unfixed element present in the treated wood. Also the decision that CCA preservative has to move from Type B to Type C should be made sooner or later for continuous use of CCA preservative in the future.

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Development of Combinational 2-Way Isohybrid for GSM1900 Base Station (GSM1900 기지국용 일체형 2-Way Isohybrid의 개발)

  • Park, Noh-Joon;Jung, Seung-Woo;Kang, Young-Jin;Choi, U-Sung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.8
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    • pp.1415-1423
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    • 2007
  • Total efficiency of transmitter system was improved by developing combinational 2-Way Isohybrid for GSM1900 base station in this paper. The size of product was decreased and the characteristics were stabilized. The isohybrid transmitter combiner of chip coupler type and hybrid coupler type were designed and fabricated. Insertion loss for chip coupler type isohybrid was $3.17\;dB{\sim}3.47\;dB$. On the other hand, insertion loss for hybrid coupler type was $3.17\;dB{\sim}3.42\;dB$. Isolations between ANT and port were $24.23\;dB{\sim}29.98\;dB$ in case of chip coupler type Isohybrid and were $26.28\;dB{\sim}36.91\;dB$ in case of hybrid coupler type, respectively.

Strength Performance Evaluation of Threaded Nail Joints of Wooden Retaining Wall Using Pitch Pine (Pinus rigida Miller) Square Timber (리기다 소나무 정각재를 사용한 목재옹벽의 직결나사못 접합부 내력 성능 평가)

  • Song, Yo-Jin;Kim, Keon-Ho;Lee, Dong-Heub;Hwang, Won-Joung;Hong, Soon-Il
    • Journal of the Korean Wood Science and Technology
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    • v.39 no.1
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    • pp.53-59
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    • 2011
  • A connection was made between a single stretcher and 2 headers with 2 threaded nails (Type-A), and another one between 2 stretchers and 2 headers with 4 threaded nails (Type-B) to use as specimens. Type-C was the stretchers that are connected with 2 threaded nails by half lap joint at end-distance 5D to reinforce Type-B, Type-C1 the stretchers that are connected by half lap joint at end-distance 10D, and Type-C2 with 3 threaded nails at end-distance 10D. Compressive shear strength of Type-C, the supplementation of Type-B, was decreased by 30%, compared with that of Type-B. Those of Type-B and Type-C1 that used longer end-distance than Type-C were about the same, and that of Type-C2 connected with 3 threaded nails was 1.28-times stronger than that of Type-C1. Connection of the retaining wall using existing square timber has a problem between long and short stretchers and 2 headers. So it was investigated in the experiment to replace it. Therefore, if Type-B is replaced with Type-C2 in constructing the retaining wall, the crack and the rupture of timber caused by threaded nail as well as construction period can be reduced, and also it can be expected to increase their own strength.

Investigation of Pretreatment Method for Gelatin Preparation from Flounder Skin (가자미피(皮) 젤라틴 제조를 위한 전처리 방법의 검토)

  • KANG Tae-Jung;JEON You-Jin;KIM Se-Kwon;SONG Dae-Jin
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.25 no.2
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    • pp.93-102
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    • 1992
  • In order to reduce long preparating time for alkali pretreated B-type gelatin, enzyme pretreatment was tried on flounder(Limanda aspera) skin for I-type gelatin. The optimal extraction conditions of the B-type gelatin were 9 folds of added water with material(w/w), 3 hrs of extraction time, $60^{\circ}C$ of extraction temperature and pH 5. The maximum amount of I-type gelatin was extracted at $60^{\circ}C$ for 3 hrs using water controlled to pH 6.0(material : water= 1:9, w/w). The yields of the B- and E-type gelatin were $64.2\%\;and\;59.2\%,$ respectively. The B-type was superior to the B-type in physical properties such as jelly strength, viscosity and electric conductivity. Molecular weight of B-type was so far larger than that of the E-type due to different pretreatment method. Hydrolysis ratio of the E-type was higher than that of the B-type because of its molecular weight. Results suggest that B-type product would be better than I-type as fish skin gelatin but E-type was desirable in hydrolyzate preparation.

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A Study on the Cone Shaped Pendants in the Period of the Three States (삼국시대 원추형 수식에 대한 연구)

  • 김문자
    • The Research Journal of the Costume Culture
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    • v.10 no.5
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    • pp.485-492
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    • 2002
  • The purpose of this study is to classify of the Cone shaped Pendants in old tombs of Three Kingdom States. These Cone shaped Pendants are made of bronze and coated with gold plate or Gold. Each Cone shaped Pendants consists of a Sehwhan(細環) type or Taewhan type, a median part in the form of a several joined small globe, or circular shape, and finally a cone-shared pendant. Cone shaped Pendants is 5 part(A-L A-b, B-1-a, B-1-b, B-2-b type) in according to the styles of the Sehwhan(細環) and Taewhan type and median ornament types. A-a, A-b, B-1-a, B-1-b type was general style that was found in most of the old tombs in Kokuryo, Pacjae, ancient Silla. B-2-b type was excavated from the only Kokuryo tombs.

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Isoenzyme pattern of Aldaline and Acid Phosphatase in the Culture of Saccharomyces uvarum (Saccharomyces uvarum의 Alkaline 및 Acid Phosphatase의 Isoenzyme 양상에 대하여)

  • 이기성;최영길
    • Korean Journal of Microbiology
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    • v.23 no.3
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    • pp.172-176
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    • 1985
  • The present study was designed to investigate isoenzyme (ACPase, ALPase) pattern and its refulatory function between catabolically repressed and derepressed states in yeast, Saccharomyces uvarum. As the results, no other isoenzyme was detectable in acid phosphatase, but there were three isoenzyme types in aldaline phosphatase. Type "B" isoenzyme among alkaline phosphatases in catabolically repressed cell was derepressed, but in normally cultivated cell, type "C" isoenzyme was derepressed while type "B" activity was lowered. Type "B" isoenzyme could be postulated as repressible enzyme, type "A" as constityityve enzyme and type "C" as L-histidinol phosphatase, respectively, Also, it could be shown that type "B" ALPase, repressible enzyme, compensated for phosphate group supplier under catabolically repressed states. Protein profile in cytoplasmic soluble fraction of exponential phase cell was characterized by negative charged protein.

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A Study on Association between Type of E-commerce and Demographic variables

  • JEONG, Dong-Bin
    • East Asian Journal of Business Economics (EAJBE)
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    • v.9 no.3
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    • pp.83-100
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    • 2021
  • Purpose - The purpose of this study is to comprehensively understand the recent status of domestic e-commerce market and provide useful information for the revitalization of domestic on-line economy. This study looks over the association between type of e-commerce and demographic variables for each purchase ordering and sales order business. The demographics under consideration is administrative district, occupation and business organization type and type of e-commerce is B2B, B2C and B2G to deal with. Research design, data, and methodology - From January 2017 to December 2017, about 14000 samples are extracted from all businesses with experience in purchasing or selling products or services through e-commerce. The association between the two categorical variables considered by using two major statistical techniques such as chi-square test and correspondence analysis can be quantitatively and visually detected. Result - This study shows the association between the type of e-commerce with the administrative district and the occupation is completely different, but B2B and B2C are identical for organization type, with respect to both purchase and sales orders. Conclusion - The association between the type of e-commerce with the administrative district and the occupation is completely different, but B2B and B2C are identical for organization type, with respect to both purchase and sales orders.

Proteolytic Conditions for the Hydrolysate of Flounder Skin Gelatin (효소에 의한 가자미피 젤라틴 가수분해물의 제조 조건)

  • 강태중;양현필;김세권;송대진
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.21 no.4
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    • pp.398-406
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    • 1992
  • In order to develop a new flavourant using the fish skin gelatin, the proteolytic renditions for the gelatin hydrolysate of the alkali (B-type) and Alcalase (E-type) pretreated flounder (Limanda aspera) skin gelatin were investigated, and some physical properties, molecular weight and amino acid compositions of the hydrolysates were, also, compared with each other. The proteolytic conditions of the gelatins (B-type and E-type) by trypsin were as follows : reaction temperature, 55$^{\circ}C$ : pH, 9.0 : enzyme concentration, 0.1% : re-action time, 4hrs for B-type and 1 hr for E-type. The degrees of hydrolysis of the B-type and E-type gelatin un-der the renditions stated above were 63% and 82%, respectively. The rnajor molecular weights of the hydrolysates were 15,000 dalton for B-type and 12,400 dalton for E-type. Among the amino acids in the hydrolysates, glycine, alanine, proline, hydroxyproline and serine having a sweet taste were responsible for 57% of the total amino acid. But valine, leucine, phenylalanine, tyrosine, methionine, arginine and histidine having a bitter taste were only 18%.

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Separation Performance of Disc Plate and Frame Type Reverse Osmosis System (원판틀형 역삼투 시스템의 투과성능)

  • 노상호;이종일;김영채;배성렬;정건용
    • Membrane Journal
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    • v.10 no.3
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    • pp.155-162
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    • 2000
  • The reverse osmosis membrane housing(HY) was developed for excellent distribution of a feed solution, and the separation performance was compared with the commercialized Rochem(RC) system. The permeation flux of HY system was a little lower than that of RC system. On the other hand, the NaCl rejection ra4io was generally higher. Also, the permeation flux and rejection ratio for type A, B and C modules(disc plate and frame type) were measured using NaCl, sucrose and butanol solutions. The separation performance of type C module for NaCL and sucrose solutions was the most effective, and then those of type A and B were followed, respectively. However, the separation performance for butanol solution was type B, C and A order. The flux improvement ratio of type B to A increased as butanol concentration decreased or operating pressure increased up to 28 bar.

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The Research of Commercial HTPB Polymer Binder Characteristics for Castable Plastic Bonded Explosive (주조형 복합화약용 HTPB 고분자 바인더의 상용모델 특성연구)

  • Lee, Seung-Jae;Kim, Jae-Woo;Park, Jong-Wan
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2011.11a
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    • pp.441-444
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    • 2011
  • Type A and Type B and are commercial HTPB models, which are very popular prepolymer for polyurethane binder family. So the study has been performed on the physical, chemical characteristic of HTPB and viscosity, mechanical property of PBX-A applying to HTPB. But We excluded the Type A from Appication test, because of law Hydroxyl value. And in the case of Type B, Type B-1, 2 has mechanical disadvatage to apply to HTPB in the process comparing with B-3. It seems to make no problem if we change equivalence ratio or curing condition within standards. But if we are to apply process condition like R-45HT(US-sample), it would be essential to apply HTPB with higher Hydroxyl Value and hydroxyl Functionality.

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