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An Exploratory Study on the Components of Visual Merchandising of Internet Shopping Mall (인터넷쇼핑몰의 VMD 구성요인에 대한 탐색적 연구)

  • Kim, Kwang-Seok;Shin, Jong-Kuk;Koo, Dong-Mo
    • Journal of Global Scholars of Marketing Science
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    • v.18 no.2
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    • pp.19-45
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    • 2008
  • This study is to empirically examine the primary dimensions of visual merchandising (VMD) of internet shopping mall, namely store design, merchandise, and merchandising cues, to be a attractive virtual store to the shoppers. The authors reviewed the literature related to the major components of VMD from the perspective of the AIDA model, which has been mainly applied to the offline store settings. The major purposes of the study are as follows; first, tries to derive the variables related with the components of visual merchandising through reviewing the existing literatures, establish the hypotheses, and test it empirically. Second, examines the relationships between the components of VMD and the attitude toward the VMD, however, putting more emphasis on finding out the component structure of the VMD. VMD needs to be examined with the perspective that an online shopping mall is a virtual self-service or clerkless store, which could reduce the number of employees, help the shoppers search, evaluate and purchase for themselves, and to be explored in terms of the in-store persuasion processes of customers. This study reviewed the literatures related to store design, merchandise, and merchandising cues which might be relevant to the store, product, and promotion respectively. VMD is a total communication tool, and AIDA model could explain the in-store consumer behavior of online shopping. Store design has to do with triggering a consumer attention to the online mall, merchandise with a product related interest, and merchandising cues with promotions such as recommendation and links that induce the desire to pruchase. These three steps might be seen as the processes for purchase actions. The theoretical rationale for the relationship between VMD and AIDA could be found in Tyagi(2005) that the three steps of consumer-oriented merchandising are a store, a product assortment, and placement, in Omar(1999) that three types of interior display are a architectural design display, commodity display, and point-of-sales(POS) display, and in Davies and Ward(2005) that the retail store interior image is related to an atmosphere, merchandise, and in-store promotion. Lee et al(2000) suggested as the web merchandising components a merchandising cues, a shopping metaphor which is an assistant tool for search, a store design, a layout(web design), and a product assortment. The store design which includes differentiation, simplicity and navigation is supposed to be related to the attention to the virtual store. Second, the merchandise dimensions comprising product assortments, visual information and product reputation have to do with the interest in the product offerings. Finally, the merchandising cues that refer to merchandiser(MD)'s recommendation of products and providing the hyperlinks to relevant goods for the shopper is concerned with attempt to induce the desire to purchase. The questionnaire survey was carried out to collect the data about the consumers who would shop at internet shopping malls frequently. To select the subject malls, the mall ranking data announced by a mall rating agency was used to differentiate the most popular and least popular five mall each. The subjects was instructed to answer the questions after navigating the designated mall for five minutes. The 300 questionnaire was distributed to the consumers, 166 samples were used in the final analysis. The empirical testing focused on identifying and confirming the dimensionality of VMD and its subdimensions using a structural equation modeling method. The confirmatory factor analysis for the endogeneous and exogeneous variables was carried out in four parts. The second-order factor analysis was done for a store design, a merchandise, and a merchandising cues, and first-order confirmatory factor analysis for the attitude toward the VMD. The model test results shows that the chi-square value of structural equation is 144.39(d.f 49), significant at 0.01 level which means the proposed model was rejected. But, judging from the ratio of chi-square value vs. degree of freedom, the ratio was 2.94 which smaller than an acceptable level of 3.0, RMR is 0.087 which is higher than a generally acceptable level of 0.08. GFI and AGFI is turned out to be 0.90 and 0.84 respectively. Both NFI and NNFI is 0.94, and CFI 0.95. The major test results are as follows; first, the second-order factor analysis and structural equational modeling reveals that the differentiation, simplicity and ease of identifying current status of the transaction are confirmed to be subdimensions of store design and to be a significant predictors of the dependent variable. This result implies that when designing an online shopping mall, it is necessary to differentiate visually from other malls to improve the effectiveness of the communications of store design. That is, the differentiated store design raise the contrast stimulus to sensory organs to promote the memory of the store and to have a favorable attitude toward the VMD of a store. The results that navigation which means the easiness of identifying current status of shopping affects the attitude to VMD could be interpreted that the navigating processes via the hyperlinks which is characteristics of an internet shopping is a complex and cognitive process and shoppers are likely to lack the sense of overall structure of the store. Consequently, shoppers are likely to be alost amid shopping not knowing where to go. The orientation tool enhance the accessibility of information to raise the perceptive power about the store environment.(Titus & Everett 1995) Second, the primary dimension of merchandise and its subdimensions was confirmed to be unidimensional respectively, have a construct validity, and nomological validity which the VMD dimensions supposed to have a positive correlation with the dependent variable. The subdimensions of product assortment, brand fame and information provision proved to have a positive effect on the attitude toward the VMD. It could be interpreted that the more plentiful the product and brand assortment of the mall is, the more likely the shoppers to favor it. Brand fame and information provision as well affect the VMD attitude, which means that the more famous the brand, the more likely the shoppers would trust and feel familiar with the mall, and the plentifully and visually presented information could have the shopper have a favorable attitude toward the store VMD. Third, it turned out to be that merchandising cue of product recommendation and hyperlinks affect the VMD attitude. This could be interpreted that recommended products could reduce the uncertainty related with the purchase decision, and the hyperlinks to relevant products would help the shopper save the cognitive effort exerted into the information search and gathering, which could lead to a favorable attitude to the VMD. This study tried to sheds some new light on the VMD of online store by reviewing the variables mentioned to be relevant with offline VMD in the existing literatures, and tried to link the VMD components from the perspective of AIDA model. The effect size of the VMD dimensions on the attitude was in the order of the merchandise, the store design and the merchandising cues.It is said that an internet has an unlimited place for display, however, the virtual store is not unlimited since the consumer has a limited amount of cognitive ability to process the external information and internal memory. Particularly, the shoppers are likely to face some difficulties in decision making on account of too many alternative and information overloads. Therefore, the internet shopping mall manager should take into consideration the cost of information search on the part of the consumer, to establish the optimal product placements and search routes. An efficient store composition would be possible by reducing the psychological burdens and cognitive efforts exerted to information search and alternatives evaluation. The store image is in most part determined by the product category and its brand it deals in. The results of this study support this proposition that the merchandise is most important to the VMD attitude than other components, the manager is required to take a strategic approach to VMD. The internet users are getting more accustomed and more knowledgeable about the internet media and more likely to accept the internet as a shopping channel as the period of time during which they use the internet to shop become longer. The web merchandiser should be aware that the product introduction using a moving pictures and a bulletin board become more important in order to present the interactive product information visually and communicate with customers more actively, therefore leading to making the quantity and quality of product information more rich.

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Studies on the Physical Properties of Major Tree Barks Grown in Korea -Genus Pinus, Populus and Quercus- (한국산(韓國産) 주요(主要) 수종(樹種) 수피(樹皮)의 이학적(理學的) 성질(性質)에 관(關)한 연구(硏究) -소나무속(屬), 사시나무속(屬), 참나무속(屬)을 중심(中心)으로-)

  • Lee, Hwa Hyoung
    • Journal of Korean Society of Forest Science
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    • v.33 no.1
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    • pp.33-58
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    • 1977
  • A bark comprises about 10 to 20 percents of a typical log by volume, and is generally considered as an unwanted residue rather than a potentially valuable resourses. As the world has been confronted with decreasing forest resources, natural resources pressure dictate that a bark should be a raw material instead of a waste. The utilization of the largely wasted bark of genus Pinus, Quercus, and Populus grown in Korea can be enhanced by learning its physical and mechanical properties. However, the study of tree bark grown in Korea have never been undertaken. In the present paper, an investigative study is carried out on the bark of three genus, eleven species representing not only the major bark trees but major species currently grown in Korea. For each species 20 trees were selected, at Suweon and Kwang-neung areas, on the same basis of the diameter class at the proper harvesting age. One $200cm^2$ segment of bark was obtained from each tree at brest height. Physical properties of bark studied are: bark density, moisture content of green bark (inner-, outer-, and total-bark), fiber saturation point, hysteresis loop, shrinkage, water absorption, specific heat, heat of wetting, thermal conductivity, thermal diffusivity, heat of combustion, and differential thermal analysis. The mechanical properties are studied on bending and compression strength (radial, longitudinal, and tangential). The results may be summarized as follows: 1. The oven-dry specific gravities differ between wood and bark, further more even for a given bark sample, the difference is obersved between inner and outer bark. 2. The oven-dry specific gravity of bark is higher than that of wood. This fact is attributed to the anatomical structure whose characters are manifested by higher content of sieve fiber and sclereids. 3. Except Pinus koraiensis, the oven-dry specific gravity of inner bark is higher than that of outer bark, which results from higher shrinkage of inner bark. 4. The moisture content of bark increases with direct proportion to the composition ratio of sieve components and decreases with higher percent of sclerenchyma and periderm tissues. 5. The possibility of determining fiber saturation point is suggested by the measuring the heat of wetting. With the proposed method, the fiber saturation point of Pinus densiflora lies between 26 and 28%, that of Quercus accutissima ranges from 24 to 28%. These results need be further examined by other methods. 6. Contrary to the behavior of wood, the bark shrinkage is the highest in radial direction and the lowest in longitudinal direction. Quercus serrata and Q. variabilis do not fall in this category. 7. Bark shows the same specific heat as wood, but the heat of wetting of bark is higher than that of wood. In heat conductivity, bark is lower than wood. From the measures of oven-dry specific gravity (${\rho}d$) and moisture fraction specific gravity (${\rho}m$) is devised the following regression equation upon which heat conductivity can be calculated. The calculated heat conductivity of bark is between $0.8{\times}10^{-4}$ and $1.6{\times}10^{-4}cal/cm-sec-deg$. $$K=4.631+11.408{\rho}d+7.628{\rho}m$$ 8. The bark heat diffusivity varies from $8.03{\times}10^{-4}$ to $4.46{\times}10^{-4}cm^2/sec$. From differential thermal analysis, wood shows a higher thermogram than bark under ignition point, but the tendency is reversed above ignition point. 9. The modulus of rupture for static bending strength of bark is proportional to the density of bark which in turn gives the following regression equation. M=243.78X-12.02 The compressive strength of bark is the highest in radial direction, contrary to the behavior of wood, and the compressive strength of longitudinal direction follows the tangential one in decreasing order.

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The Acid-resistant Characteristic of Organic Acid Tolerance Mutant of Leuconostoc paramesenteroides (Leuconostoc paramesenteroides 유기산 내성 변이균주의 내산성 특성)

  • Kim, Young-Hwan;Kim, Hee-Zoong;Oh, Kyun-Sik;Kim, Sun-Young;Lee, Si-Kyung;Kang, Sang-Mo
    • Korean Journal of Food Science and Technology
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    • v.40 no.4
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    • pp.424-429
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    • 2008
  • To investigate the acid tolerance characteristics of the acid-resistant mutant, Leuconostoc paramesenteroides P-200, as a kimchi starter, this study examine proton permeability, ATPase activity, glycolysis activity, $Mg^{2+}$ release, and membrane fatty acid composition, and compared the data to that of its wild-type, L. paramesenteroides LP-W. In the proton permeability experiment, the LP-W and P-200 strains' average maximum half-time $(t_{1/2})$ values for pH equilibration through the cell membrane were approximately 5.7 and 9.3 min in 150mM KCl solution, and 4.2 and 8.3 min in 3% NaCl solution, respectively. Their values and pH levels for maximal specific ATPase activity showed that P-200 had greater activity than LPW. And the results of pH-dependent glycolysis activity showed that P-200 had greater activity than LP-W. Furthermore, after 2 hr at pH 4.0, LP-W and P-200 had percent magnesium release values of approximately 12% and 34%, respectively. A comparison of their membrane fatty acid compositions indicated that C18 and cyclo-C19 were the major different fatty acids between the two strains, and their contents of C18 and cyclo-C19 were 2.5% and not detected, respectively, in LP-W, and 6.4% and 11.4%, respectively, in P-200. These results indicate that the P-200 strain has significantly improved acid tolerance as compared to its wild type, LP-W.

Annual Variation of Water Quality and Bivalvia Communities in Gamak Bay (가막만의 수질환경과 이매패류(Bivalvia)군집의 연간변동)

  • Kim, Yun-Seol;Yoon, Ho-Seop;Park, Il-Woong;Lee, Woo-Bum;Joo, Seung-Yong;Choi, Sang-Duk
    • Korean Journal of Environmental Biology
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    • v.26 no.4
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    • pp.279-291
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    • 2008
  • The seasonal distribution pattern of the Bivalvia samples collected from 12 stations in Gamak Bay in April, July, September and November from 2001 to 2006. A total of 28 species (226.72$\pm$196.20 ind. m$^{-2}$) were identified. The COD has decreased from 3.30 mg L$^{-1}$ to 1.89 mg L$^{-1}$ level on average and especially, the COD of sediment has decreased from 21.51 mg g-dry$^{-1}$ to 16.99 mg g-dry$^{-1}$ level on average. Therefore, water quality level of Gamak Bay was improved from level 3 to 2. The dominant species over 1.0 percentages were composed of the total 13 species, and they occupied 96.75% of the total density of the Bivalvia. Major dominant species was Musculista senhousia 100.38 ind. m$^{-2}$ (22.16%), Moerella rutila 69.00 ind. m$^{-2}$ (15.23%), Theorafragilis 49.70 ind. m$^{-2}$ (10.97%), Mytilus edulis 42.18 ind. m$^{-2}$ (9.31 %), and Raphia undulata 40.99 ind. m$^{-2}$ (9.05%). This area could be divided into three groups by the cluster analysis based on the total species composition.

Nutritional Properties of ChOl-PyOn Preparation by Adding Mugwort and Pine leaves (쑥과 솔잎을 첨가한 절편의 영양학적 특성)

  • 김종군
    • Korean journal of food and cookery science
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    • v.11 no.5
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    • pp.446-455
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    • 1995
  • The nutritional properties of the Chol-Pyon were investigated with changing the materials (mugwort and pine leaves). In proximate composition, rice powder added mugwort and pine leaves showed the lligher con-tents of crude protein, crude lipid and crude ash than in rice powder. Ihe pH of rice powder, mugwort and pine leaves was 6.4, 6.8 and 3.5, respectively. The rice powder added pine leaves showed the lowest pH value. The content of the free sugar in raw materials for ChOl-PyOn preparation was 0.9% in rice powder, 0.3% in mugwort and 2.7% in pine leaves. Eighteen kinds of amino acids were determined in raw materials for ChOl-fyOn preparation and their contents were 4.8% in mugwort, 4.2% in rice powder and 2.8% in pine leaves. The major minerals of raw materials for ChOl-PyOn preparation was 0.9% increased in the order of K> Na > Mg > Ca in rice powder, Mg > K > Ca > Na in mugwort, and K > Ca > Mg > Na in pine leaves. Both of mugwort and pine leaves additives showed the higher contents of 8 kinds of minerals (Ca, Mg, K, Na, Mn, Fe, Cu, Zn) than in rice powder. In relation to changes in the texture of ChOl-PyOn, hardness, fracturability and adhesiveness at 25${\pm}$1$^{\circ}C$ were measured to be highest in white ChOl-PyOn. Cohesiveness was shown to be highest at 15% in case of mugwort and 2.5% in case of pine leaves. Elasticity was measured to be highest at 0.99 in case that 7.5% mugwort was added to raw materials for ChOl-PyOn. As a result of estimating the sensory qualities of the ChOl-PyOn prepared to which the additives were added in differing amounts, immediately after its preparation the mugwort additive of 7.5% showed the superior sensory qualities Chol-PyOn (p < 0,01).

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Occurrence and Geochemical Characteristics of the Haenam Pb-Zn Skarn Deposit (해남 연-아연 스카른광상의 산상과 지화학적 특성)

  • Im, Heonkyung;Shin, Dongbok;Heo, Seonhee
    • Economic and Environmental Geology
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    • v.47 no.4
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    • pp.363-379
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    • 2014
  • The Haenam Pb-Zn skarn deposit is located at the Hwawon peninsula in the southwestern part of the Ogcheon Metamorphic Belt. The deposit is developed along the contact between limestone of the Ogcheon group and Cretaceous quartz porphyry. Petrography of ore samples, chemical composition of skarn and ore minerals, and geochemistry of the related igneous rocks were investigated to understand the characteristics of the skarn mineralization. Skarn zonation consists of garnet${\pm}$pyroxene${\pm}$calcite${\pm}$quartz zone, pyroxene+garnet+quartz${\pm}$calcite zone, calcite+pyroxene${\pm}$garnet zone, quartz+calcite${\pm}$pyroxene zone, and calcite${\pm}$chlorite zone in succession toward carbonate rock. Garnet commonly shows zonal texture comprised of andradite and grossular. Pyroxene varies from Mn-hedenbergite to diopside as away from the intrusive rock. Chalcopyrite occurs as major ore mineral near the intrusive rock, and sphalerite and galena tend to increase as going away. Electron probe microanalyses revealed that FeS contents of sphalerite become decreased from 5.17 mole % for garnet${\pm}$pyroxene${\pm}$calcite${\pm}$quartz zone to 2.93 mole %, and to 0.40 mole % for calcite+pyroxene${\pm}$garnet zone, gradually. Ag and Bi contents also decreased from 0.72 wt.% and 1.62 wt.% to <0.01 wt.% and 0.11 wt.%, respectively. Thus, the Haenam deposit shows systematic variation of species and chemical compositions of ore minerals with skarn zoned texture. The related intrusive rock, quartz porphyry, expresses more differentiated characteristics than Zn-skarn deposit of Meinert(1995), and has relatively high$SiO_2$ concentration of 72.76~75.38 wt.% and shows geochemical features classified as calc-alkaline, peraluminous igneous rock and volcanic arc tectonic setting.

Lithologic and Structural Controls and Geochemistry of Uranium Deposition in the Ogcheon Black-Slate Formation (옥천대(沃川帶) 우라늄광층(鑛層)의 구조규제(構造規制) 및 지구화학적(地球化學的) 특성연구(特性硏究))

  • Lee, Dai Sung;Yun, Suckew;Lee, Jong Hyeog;Kim, Jeong Taeg
    • Economic and Environmental Geology
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    • v.19 no.spc
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    • pp.19-41
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    • 1986
  • Structural, radioactive, petrological, petrochemical, mineralogical and stable isotopic study as well as the review of previous studies of the uranium-bearing slates in the Ogcheon sequence were carried out to examine the lithological and structural controls, and geochemical environment in the uranium deposition in the sequence. And the study was extended to the coal-bearing formation (Jangseong Series-Permian) to compare the geochemical and sedimentologic aspects of uranium chemistry between Ogcheon and Hambaegsan areas. The results obtained are as follows: 1. The uranium mineralization occurs in the carbonaceous black slates of the middle to lower Guryongsan formation and its equivalents in the Ogcheon sequence. In general, two or three uranium-bearing carbonaceous beds are found with about 1 to 1.5km stratigraphic interval and they extend from Chungju to Jinsan for 90km in distance, with intermittent igneous intrusions and structural Jisturbances. Average thickness of the beds ranges from 20 to 1,500m. 2. These carbonaceous slate beds were folded by a strong $F_1$-fold and were refolded by subsequent $F_1$-fold, nearly co-axial with the $F_1$, resulting in a repeated occurrence of similar slate. The carbonaceous beds were swelled in hing zones and were shrinked or thined out in limb by the these foldings. Minor faulting and brecciation of the carbonaceous beds were followed causing metamorphism of these beds and secondary migration and alteration of uranium minerals and their close associations. 3. Uranium-rich zones with high radioactive anomalies are found in Chungju, Deogpyong-Yongyuri, MiwonBoun, Daejeon-Geumsan areas in the range of 500~3,700 cps (corresponds to 0.017~0.087%U). These zones continue along strike of the beds for several tens to a few hundred meters but also discontinue with swelling and pinches at places that should be analogously developed toward underground in their vertical extentions. The drilling surveyings in those area, more than 120 holes, indicate that the depth-frequency to uranium rich bed ranging 40~160 meter is greater. 4. The features that higher radioactive anomalies occur particularly from the carbonaceous beds among the argillaceous lithologic units, are well demonstrated on the cross sections of the lithology and radioactive values of the major uranium deposits in the Ogcheon zone. However, one anomalous radioactive zone is found in a l:ornfels bed in Samgoe, near Daejeon city. This is interpreted as a thermal metamorphic effect by which original uranium contents in the underlying black slate were migrated into the hornfels bed. 5. Principal minerals of the uranium-bearing black slates are quartz, sericite, biotite and chlorite, and as to chemical composition of the black slates, $Al_2O_3$ contents appear to be much lower than the average values by its clarke suggesting that the Changri basin has rather proximal to its source area. 6. The uranium-bearing carbonaceous beds contain minor amounts of phosphorite minerals, pyrite, pyrrhotite and other sulfides but not contain iron oxides. Vanadium. Molybdenum, Barium, Nickel, Zirconium, Lead, Cromium and fixed Carbon, and some other heavy metals appear to be positive by correlative with uranium in their concentrations, suggesting a possibility of their genetic relationships. The estimated pH and Eh of the slate suggests an euxenic marine to organic-rich saline water environment during uranium was deposited in the middle part of Ogcheon zone. 7. The Carboniferous shale of Jangseong Series(Sadong Series) of Permian in Hambaegsan area having low radioactivity and in fluvial to beach deposits is entirely different in geochemical property and depositional environment from the middle part of Ogcheon zone, so-called "Pibanryong-Type Ogcheon Zone". 8. Synthesizing various data obtained by several aspects of research on uranium mineralization in the studied sequence, it is concluded that the processes of uranium deposition were incorporated with rich organic precipitation by which soluble uranyl ions, $U{_2}^{+{+}}$ were organochemically complexed and carried down to the pre-Ogcheon sea bottoms formed in transitional environment, from Red Sea type basin to Black Sea type basin. Decomposition of the organic matter under reducing conditions to hydrogen sulfide, which reduced the $UO{_2}^{+2}$ ions to the insoluble uranium dioxide($UO_2$), on the other side the heavy metals are precipitated as sulfides. 9. The EPMA study on the identification of uraninite and others and the genetic interpretation of uranium bearing slates by isotopic values of this work are given separately by Yun, S. in 1984.

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Effect of Additives on Paper Aging (종이 첨가제가 종이의 노화에 미치는 영향)

  • 윤병호;이명구;최경화
    • Journal of Korea Foresty Energy
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    • v.21 no.2
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    • pp.25-33
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    • 2002
  • One of the critical problems to preserve books and documents in libraries and archives is the deterioration. Some of previous results showed that the major cause of paper deterioration was the acid-catalyzed hydrolysis of the cellulose in paper fibres and aging rate of acidic paper was faster than that of alkaline paper. Therefore, It is necessary to remove the acid in the paper for reducing the rate of paper deterioration. It has been reported to extend the useful life of acidic paper by three to five times. Recently, It has been recognized the need for an effective method of deacidifying large quantities of books and document. However, in the previous many reports little attention was paid to the effect of paper additives. In this paper, We carried out experiment about the effect of additives on paper aging and the effect of deacidification by the gaseous ethanolamines (monoehtanolamine, diethanolamine, triehtanolamine). In result, it was found that the strength of aging was in the order of the alum+rosin>alum >AKD> control and the rate of deacidification was in the order of the monoethanolamine>diethanolamine>triethanolamine. The treatment with the gaseous ethanolamines caused decreasing of brightness and dropping of fold endurances. However, deacidification by combination treatment of the various gaseous ehtnaolamines prevented from decreasing of brightness and dropping of folding endurances.

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Ionic composition and pollution characteristics of precipitation in Jeju Island during 2009-2014 (2009-2014년 제주지역 강수의 이온조성 및 오염특성)

  • Bu, Jun Oh;Song, Jung Min;Shin, Su Hyun;Kim, Won Hyung;Kang, Chang Hee
    • Analytical Science and Technology
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    • v.29 no.1
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    • pp.19-28
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    • 2016
  • The objective of this study was to determine the acidification of precipitation in the Jeju area. Precipitation samples were collected from the Jeju area from 2009-2014, and the major ionic species were analyzed. In the regression analysis, through a comparison of ion balance, electric conductivity, and acid fraction, the correlation coefficients showed a good linear relationship within the range of 0.927~0.983. The volume-weighted means of the pH and electric conductivity were 4.9 and 22.7 µS/cm, respectively. The ionic strength of precipitation was 0.27±0.38 mM, indicating about 35.9 % of total precipitation within the pure precipitation criteria. The volume-weighted mean concentrations (ìeq/L) of the ionic species in the precipitation were in the order of Na+ > Cl > nss-SO42− > NO3 > NH4+ > Mg2+ > H+ > nss-Ca2+ > PO43− > K+ > HCOO > CH3COO > NO2 > F > HCO3 > CH3SO3 . The acidification contributions by sulfuric and nitric acids were 54.5 % and 36.5 %, respectively. Meanwhile the acidification contributions by formic and acetic acids were 4.8 % and 4.2 %, respectively. Thus, it was found that the acidification of the precipitation in the Jeju area was mainly due to the inorganic acids. The neutralization factors by NH3 and CaCO3 were also 33 % and 20 %, respectively.

Characterization of a Korean Domestic Cyanobacterium Limnothrix sp. KNUA012 for Biofuel Feedstock (토착 남세균 림노트릭스 속 KNUA012 균주의 바이오연료 원료로서의 특성 연구)

  • Hong, Ji Won;Jo, Seung-Woo;Kim, Oh Hong;Jeong, Mi Rang;Kim, Hyeon;Park, Kyung Mok;Lee, Kyoung In;Yoon, Ho-Sung
    • Journal of Life Science
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    • v.26 no.4
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    • pp.460-467
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    • 2016
  • A filamentous cyanobacterium, Limnothrix sp. KNUA012, was axenically isolated from a freshwater bloom sample in Lake Hapcheon, Hapcheon-gun, Gyeongsangnam-do, Korea. Its morphological and molecular characteristics led to identification of the isolate as a member of the genus Limnothrix. Maximal growth was attained when the culture was incubated at 25℃. Analysis of its lipid composition revealed that strain KNUA012 could autotrophically synthesize alkanes, such as pentadecane (C15H32) and heptadecane (C17H36), which can be directly used as fuel without requiring a transesterification step. Two genes involved in alkane biosynthesis-an acyl-acyl carrier protein reductase and an aldehyde decarbonylase-were present in this cyanobacterium. Some common algal biodiesel constituents-myristoleic acid (C14:1), palmitic acid (C16:0), and palmitoleic acid (C16:1)-were produced by strain KNUA012 as its major fatty acids. A proximate analysis showed that the volatile matter content was 86.0% and an ultimate analysis indicated that the higher heating value was 19.8 MJ kg−1. The isolate also autotrophically produced 21.4 mg g−1 phycocyanin-a high-value antioxidant compound. Therefore, Limnothrix sp. KNUA012 appears to show promise for application in cost-effective production of microalga-based biofuels and biomass feedstock over crop plants.