• Title/Summary/Keyword: Intermediate products

검색결과 374건 처리시간 0.034초

Antimicrobial Properties of Wheat Gluten-Chitosan Composite Film in Intermediate-Moisture Food Systems

  • Park, Sang-Kyu;Bae, Dong-Ho
    • Food Science and Biotechnology
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    • 제15권1호
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    • pp.133-137
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    • 2006
  • Wheat gluten-chitosan composite film (WGCCF) can prevent moisture migration and enhance the antimicrobial properties of gluten in intermediate-moisture foods like sandwiches. To mimic the structure of actual sandwich-type products we developed multi-layer food models, where moisture content and water activity differ. Water activity gradients direct moisture migration and therefore determine product characteristics and product stability. A 10% wheat gluten film-forming solution was mixed with chitosan film-forming solution (0-3%, w/w) and evaporated to generate WGCCF. Addition of 3% chitosan enhanced the mechanical properties of the film composite, lowered its water vapor permeability, and improved its ability to protect against both, Streptococcus faecalis and Escherichia coli, in a 24 hr sandwich test (reduction of 1.3 and 2.7 log cycles, respectively, compared to controls). Best barrier and antimicrobial performance was found for 3% chitosan WGCCF at pH 5.1. Film of this type may find application as barrier film for intermediate-moisture foods.

냉간압연용 장수명 중간롤 개발 (Development of intermediate roll which has a long life for cold rolling mills)

  • 박영철;김병훈;김일봉;김정태;김현문;이우동
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2004년도 제5회 압연심포지엄 신 시장 개척을 위한 압연기술
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    • pp.207-215
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    • 2004
  • There are various characteristics called for in work roll and intermediate rolls for cold rolling mills. Among these characteristics, the two main requirements are to ensure the quality of the rolled products and to reduce roll cost. To achieve these needs, resistance to wear, to thermal shock and to contact fatigue are especially important. This paper describes that new material(named DSR1) for intermediate rolls which greatly increases rolling campaign and improves resistance to wear has been developed. DSR1 was successfully manufactured and has been used in the cold rolling mill. It showed that Trial product was homogenous in hardness distribution and sufficient usable diameter. Also in service test, trial product is much more excellent rolling performance than conventional $5\%Cr$.

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Formation Mechanism of Intermediate Phase in $Ba(Mg_{1/3}Ta_{2/3})O_3$ Microwave Dielectrics

  • Fang, Yonghan;Oh, Young-Jei
    • 한국세라믹학회지
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    • 제38권10호
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    • pp.881-885
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    • 2001
  • Kinetics and mechanisms of intermediate phases formation in $Ba(Mg_{1/3}Ta_{2/3})O_3$, obtained by a solid state reaction were studied. $Ba{Ta_2}{O_6}$ and ${Ba_4}{Ta_2}{O_9}$ as intermediate products were first formed at $700^{\circ}C$. $Ba(Mg_{1/3}Ta_{2/3})O_3$ was appeared at $800^{\circ}C$. Several reactions take place on heating process. $Ba{Ta_2}{O_6}$ is found at the first stage of the reaction, and then $Ba{Ta_2}{O_6}$ or ${Ba_4}{Ta_2}{O_9}$ react with MgO to form $Ba(Mg_{1/3}Ta_{2/3})O_3$. The reaction of $Ba(Mg_{1/3}Ta_{2/3})O_3$ formation does not complete until fired at $1350^{\circ}C$ for 60 min. The kinetics of solid-state reaction between powdered reactants was controlled by diffusion mechanism, and can be explained by the Jander's model for three-dimensional diffusion.

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페니토인 제제의 생체이용률에 관한 연구 (The Study on the Bioavailability of the Phenytoin Products)

  • 박경호;김낙두;이민화
    • 약학회지
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    • 제30권1호
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    • pp.14-23
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    • 1986
  • This study was conducted to investigate the correlation between the dissolution rates and the bioavailabilities of commercial phenytoin products, and also the correlation between their biovailabilities in rabbits and those in humans. Dissolution test was conducted in pH 9. 0 alkaline borate buffer (0.2M) using basket method with seven phenytoin products commercially available. According to the dissolution rate, the phenytoin products were divided into three groups, such as rapid, intermediate and slow group. Three phenytoin products from each group were selected for the bioavailability test in rabbits and humans. The bioavailability test was carried out in rabbits and normal volunteers using cross over design. Single doses of 20mg/kg and 300mg/man were orally administered to rabbits and normal volunteers respectively. Average $C_{max}$, $t_{max}$ and AUC of three phenytoin products were determined from the serum concentration-time curve in rabbit and human experiments. The relative bioavailability evaluation was conducted using AUC of three phenytoin products. The correlations between the dissolution rate constants and bioavailabilities (AUC) of three phenytoin products in rabbits as well as those in humans were not found. Whereas, there was significant correlation between average AUC of three phenytoin products in humans and those in rabbits (r=0.993, p<0.1). From the results of this experiment, it can be concluded that the bioavailability of phenytoin products in humans may be predicted from the results of the rabbit experiment. Also it is assumed that the prediction of the bioavailability of phenytoin products in humans may be difficult from the only results of in vitro dissolution test.

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산업관련표(産業關聯表)에 의(依)한 임업구조분석(林業構造分析)과 유발생산액(誘發生産額) -임업(林業)이 한국경제(韓國經濟)에 미치는 영향(影響)- (Analysis of Forestry Structure and Induced Output Based on Input - output Table - Influences of Forestry Production on Korean Economy -)

  • 이승윤
    • Journal of the Korean Wood Science and Technology
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    • 제2권4호
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    • pp.4-14
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    • 1974
  • The total forest land area in Korea accounts for some 67 percent of the nation's land total. Its productivity, however, is very low. Consequently, forest production accounts for only about 2 percent of the gross national product and a minor proportion of no more than about 5 percent versus primary industry. In this case, however, only the direct income from forestry is taken into account, making no reference to the forestry output induced by other industrial sectors. The value added Or the induced forestry output in manufacturing the primary wood products into higher quality products, makes a larger contribution to the economy than direct contribution. So, this author has tried to analyze the structure of forestry and compute the repercussion effect and the induced output of primary forest products when utilized by other industries for their raw materials, Hsing the input-output table and attached tables for 1963 and 1966 issued by the Bank of Korea. 1. Analysis of forestry structure A. Changes in total output Durng the nine-year period, 1961-1969, the real gross national product in Korea increased 2.1 times, while that of primary industries went up about 1. 4 times. Forestry which was valued at 9,380 million won in 1961, was picked up about 2. 1 times to 20, 120 million won in 1969. The rate of the forestry income in the GNP, accordingly, was no more than 1.5 percent both in 1961 and 1962, whereas its rate in primary industries increased 3.5 to 5.4 percent. Such increase in forestry income is attributable to increased forest production and rise in timber prices. The rate of forestry income, nonetheless, was on the decrease on a gradual basis. B. Changes in input coefficient The input coefficient which indicates the inputs of the forest products into other sectors were up in general in 1966 over 1963. It is noted that the input coefficient indicating the amount of forest products supplied to such industries closely related with forestry as lumber and plywood, and wood products and furniture, showed a downward trend for the period 1963-1966. On the other hand, the forest input into other sectors was generally on the increase. Meanwhile, the input coefficient representing the yolume of the forest products supplied to the forestry sector itself showed an upward tendency, which meant more and more decrease in input from other sectors. Generally speaking, in direct proportion to the higher input coefficient in any industrial sector, the reinput coefficient which denotes the use of its products by the same sector becomes higher and higher. C. Changes in ratio of intermediate input The intermediate input ratio showing the dependency on raw materials went up to 15.43 percent m 1966 from 11. 37 percent in 1963. The dependency of forestry on raw materials was no more than 15.43 percent, accounting for a high 83.57 percent of value added. If the intermediate input ratio increases in any given sector, the input coefficient which represents the fe-use of its products by the same sector becomes large. D. Changes in the ratio of intermediate demand The ratio of the intermediate demand represents the characteristics of the intermediary production in each industry, the intermediate demand ratio in forestry which accunted for 69.7 percent in 1963 went up to 75.2 percent in 1966. In other words, forestry is a remarkable industry in that there is characteristics of the intermediary production. E. Changes in import coefficient The import coefficient which denotes the relation between the production activities and imports, recorded at 4.4 percent in 1963, decreased to 2.4 percent in 1966. The ratio of import to total output is not so high. F. Changes in market composition of imported goods One of the major imported goods in the forestry sector is lumber. The import value increased by 60 percent to 667 million won in 1966 from 407 million won in 1963. The sales of imported forest products to two major outlets-lumber and plywood, and wood products and furniture-increased to 343 million won and 31 million won in 1966 from 240million won and 30 million won in 1963 respectively. On the other hand, imported goods valued at 66 million won were sold to the paper products sector in 1963; however, no supply to this sector was recorded in 1963. Besides these major markets, primary industries such as the fishery, coal and agriculture sectors purchase materials from forestry. 2. Analysis of repercussion effect on production The repercussion effect of final demand in any given sector upon the expansion of the production of other sectors was analyzed, using the inverse matrix coefficient tables attached to the the I.O. Table. A. Changes in intra-sector transaction value of inverse matrix coefficient. The intra-sector transaction value of an inverse matrix coefficient represents the extent of an induced increase in the production of self-support products of the same sector, when it is generated directly and indirectly by one unit of final demand in any given sector. The intra-sector transaction value of the forestry sector rose from 1.04 in 1963 to 1, 11 in 1966. It may well be said, therefore, that forestry induces much more self-supporting products in the production of one unit of final demand for forest products. B. Changes in column total of inverse matrix coefficient It should be noted that the column total indicates the degree of effect of the output of the corresponding and related sectors generated by one unit of final demand in each sector. No changes in the column total of the forestry sector were recorded between the 1963 and 1966 figures, both being the same 1. 19. C. Changes in difference between column total and intra-sector transaction amount. The difference between the column total and intra-sector transaction amount by sector reveals the extent of effect of output of related industrial sector induced indirectly by one unit of final demand in corresponding sector. This change in forestry dropped remarkable to 0.08 in 1966 from 0.15 in 1963. Accordingly, the effect of inducement of indirect output of other forestry-related sectors has decreased; this is a really natural phenomenon, as compared with an increasing input coefficient generated by the re-use of forest products by the forestry sector. 3. Induced output of forestry A. Forest products, wood in particular, are supplied to other industries as their raw materials, increasng their value added. In this connection the primary dependency rate on forestry for 1963 and 1966 was compared, i. e., an increase or decrease in each sector, from 7.71 percent in 1963 to 11.91 percent in 1966 in agriculture, 10.32 to 6.11 in fishery, 16.24 to 19.90 in mining, 0.76 to 0.70 in the manufacturing sector and 2.79 to 4.77 percent in the construction sector. Generally speaking, on the average the dependency on forestry during the period 1963-1966 increased from 5.92 percent to 8.03 percent. Accordingly, it may easily be known that the primary forestry output induced by primary and secondary industries increased from 16, 109 million won in 1963 to 48, 842 million won in 1966. B. The forest products are supplied to other industries as their raw materials. The products are processed further into higher quality products. thus indirectly increasing the value of the forest products. The ratio of the increased value added or the secondary dependency on forestry for 1963 and 1966 showed an increase or decrease, from 5.98 percent to 7.87 percent in agriculture, 9.06 to 5.74 in fishery, 13.56 to 15.81 in mining, 0.68 to 0.61 in the manufacturing sector and 2.71 to 4.54 in the construction sector. The average ratio in this connection increased from 4.69 percent to 5.60 percent. In the meantime, the secondary forestry output induced by primary and secondary industries rose from 12,779 million Wall in 1963 to 34,084 million won in 1966. C. The dependency of tertiary industries on forestry showed very minor ratios of 0.46 percent and 0.04 percent in 1963 and 1966 respectively. The forestry output induced by tertiary industry also decreased from 685 million won to 123 million won during the same period. D. Generally speaking, the ratio of dependency on forestry increased from 17.68 percent in 1963 to 24.28 percent in 1966 in primary industries, from 4.69 percent to 5.70 percent in secondary industries, while, as mentioned above, the ratio in the case of tertiary industry decreased from 0.46 to 0.04 percent during the period 1963-66. The mining industry reveals the heaviest rate of dependency on forestry with 29.80 percent in 1963 and 35.71 percent in 1966. As it result, the direct forestry income, valued at 8,172 million won in 1963, shot up to 22,724 million won in 1966. Its composition ratio lo the national income rose from 1.9 percent in 1963 to 2.3 per cent in 1966. If the induced outcome is taken into account, the total forestry production which was estimated at 37,744 million won in 1963 picked up to 105,773 million won in 1966, about 4.5 times its direct income. It is further noted that the ratio of the gross forestry product to the gross national product. rose significantly from 8.8 percent in 1963 to 10.7 percent in 1966. E. In computing the above mentioned ratio not taken into consideration were such intangible, indirect effects as the drought and flood prevention, check of soil run-off, watershed and land conservation, improvement of the people's recreational and emotional living, and maintenance and increase in the national health and sanitation. F. In conclusion, I would like to emphasize that the forestry sector exercices an important effect upon the national economy and that the effect of induced forestry output is greater than its direct income.

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2-Deoxy-2-fluoro-D-arabinofuranose류의 합성 연구 (Synthesis of 2-Deoxy-2-fluoro-D-arabinofuranose Derivatives)

  • 천문우;김문환;김득준;정원근
    • 약학회지
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    • 제28권3호
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    • pp.191-195
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    • 1984
  • A ten-step synthesis of 1, 3-di-O-acetyl-5-O-benzoyl-2-deoxy-2-fluoro-D-arabino-furanose, a versatile intermediate in the synthesis of chemotherapeutically important nucleosides, was achieved from D-glucose. This procedure affords good overall yields of products and is suitable for large scale preparations.

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N-acyloxyethylcarboxybetaine 형 양성계면활성제의 합성과 물성에 관한 연구 (A Study on the Synthesis and Physical Properties of N-acyloxyethyl carboxybetaine Type Amphoteric Surfactants)

  • 김용인;소희전;오양환;김병기
    • 한국응용과학기술학회지
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    • 제6권1호
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    • pp.31-40
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    • 1989
  • Five novel amphoteric surfactants of N-acyloxyethylcarboxybetaine series were synthesized via Schotten-Baumman reaction between five acid chlorides containing 10, 12, 14, 16 and 18 carbon atoms in their N-alkyl groups and dimethylaminoethanol to give the intermediate products, 2-dimethylaminoethylalkanoates(2). Quaternization of these products(2) was permitted to from 2-(acyloxyethyldimethylammonic)- acetates(3), whose structures were identified by elemental analysis, IR spectrophotometry and $^1Hnmr$ spectrometry. The yield of the final products was shown in the range of 77-80% based on the intermediate products. The surface tension of the aqueous solution of (3) was measured, and the critical micelle concentrations (cmc) were shown in the range of $2.1\;{\times}\;10^{-3}\;-\;3.3\;{\times}\;10^{-4}mol/l$, and the surface tension at cmc was 28-36 dyne/cm. Cmc was lowered gradually by the increment of the length of N-alkyl ester containing group. The isoelectric point was shown in the range of 4.44-5.20. It showed a tendency to lean toward the acidic site and its range was broadened as increase of the hydrophobic group length. A linear relationship between log cmc and the number of carbon atoms(N) in the hydrophobic alkyl chain was shown in the relative equation of log cmc=-1.75-0.1N, and the contribution rate of N on the standard free energy change in micellization, ${\bigtriangleup}({\bigtriangleup}G^{\circ}m)/{\bigtriangleup}N$, was calculated as -0.23 RT.

에테르 결합을 가진 베타인계 양성계면활성제(兩性界面活性濟) 합성(合成) 및 계면활성(界面活性) (Synthesis and Surface Activities of Betaine Amphoteric Surfactant Having Ether Bond)

  • 차경온;이희종;김용인
    • 한국응용과학기술학회지
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    • 제9권1호
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    • pp.63-71
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    • 1992
  • Four novel amphoteric surfactants of N-alkoxyethylcarboxybetaine series were synthesized via Schotten-Baurnman reaction between four alkyl chlorides contaning 10, 12, 14 and 16 carbon atoms in their N-alkyl group and dimethylaminoethanol to give the intermediate products, alkoxyethyldimethylamine, Quaternization of these intermediates was permitted to form 2-(alkoxyethyldimethylarnmonio) acetates, whose structures were identified by elemental analysis. IR spectrophotometry and $^1$Hnmr spectrometry. The yield of the final products was shown in the range of $74{\sim}77%$ based on the yield of the intermediate products, Surface tension of the aqueous solution of the final products was measured. and the critical micelle concentrations(cmc) were shown in the range of $2.82{\times}10^{-3}{\sim}2.67{\times}10^{-6}$mol/l, and the surface thension at erne was 35${\sim}$43dyne/cm. Cmc was lowered gradually by the increase of carbon numbers in N-alkyl ether containing group. The isoelectric point was shown in the range of 4.08${\sim}$6.03. It showed a tendency to lean toward the acidic site and its range was broadened as increase of the hydrophobic group length. A linear relationship between log erne and the number of carbon atoms(N) in the hydrophobic alkyl chain was shown in the relative equation of log cmc=2.49-0.50N.

생산요소가격의 변화가 제조산업 마크업에 미치는 영향에 관한 실증분석 (Empirical Analysis on the Effects of the Input Factor Price on the Industrial Markups in Korean Manufacturing Industries)

  • 강주훈
    • 국제지역연구
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    • 제20권2호
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    • pp.47-62
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    • 2016
  • 본 논문은 마크업방정식을 설정하여 8개 제조산업의 산업별 마크업을 추정한 다음, 자기회귀시차모형을 추정하여 마크업의 요소가격탄력도를 산업별로 추정하였다. 또한 산업의 특성을 반영하는 산업의 자본집약도와 수입중간재비중을 고려하여 생산요소가격이 마크업을 결정하는 중요 변수임을 밝히고 있다. 분석결과 수입중간재비중이 높은 기계 전자 운송, 화학제품 그리고 금속제품산업에 있어서 마크업의 수입물가지수탄력도는 각각 -1.025, -0.176, -0.260으로 추정되었으며 자본집약적인 산업인 화학제품, 금속제품 그리고 기계 전자 운송의 경우, 이자율탄력도는 각각 -0.165, -0.147 그리고 -0.210으로 나타났다. 따라서 마크업의 주요 결정요소는 생산요소가격 그리고 산업의 특성을 반영하는 자본집약도와 해외중간재 비중이라 할 수 있다. 분석결과는 산업의 자본집약도가 클수록 그리고 해외중간재 비중이 큰 산업일수록 이자율과 수입물가지수의 변동은 산업별 마크업을 결정하는데 있어서 더욱 큰 영향을 주었음을 밝히고 있다.

크로스 롤러 가이드 다단 형상인발 공정설계에 관한 연구 (Process Design of Multi-Stage Shape Drawing Process for Cross Roller Guide)

  • 이상곤;이재은;이태규;이선봉;김병민
    • 한국정밀공학회지
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    • 제26권11호
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    • pp.124-130
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    • 2009
  • In the multi-stage shape drawing process, the most important aspect for the economy is the correct design of the various drawing stage. For most of the products commonly available round or square materials can be used as initial material. However, special products should be pre-rolled. This study proposes a process design method of multi-stage shape drawing process for producing cross roller guide. Firstly, a standard classification of shape drawing process is suggested based on the requirement of pre-rolling process. And a design method is proposed to design the intermediate die shape. The process design method is applied to design the multi-stage shape drawing process for producing cross roller guide. Finally, the effectiveness of the proposed design method is verified by FE-analysis and shape drawing experiment.