• Title/Summary/Keyword: bond characteristic

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Deterioration Characteristic of Shotcrete Immersed in Chemical Solution (화학적 침식에 의한 숏크리트의 열화특성 분석 - 단기거동)

  • Lee, Gyu-Phil;Kim, Dong-Gyou;Bae, Gyu-Jin;Shin, Hyu-Soung
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.7 no.2
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    • pp.143-152
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    • 2005
  • Shotcrete for support of tunnel structures may contact with groundwater. The hazardous components in groundwater may cause corrosion of shotcrete. Also, the hazardous components may deteriorate the engineering properties of shotcrete, such as compressive strength, bond strength, flexural strength and so forth. The more the effect of the hazardous components on the shotcrete may increase, the more the stability of tunnel structure may decrease. The specimens were artificially immersed in various chemical solutions including hazardous components after the specimens were made at the tunnel construction site. It was performed to analyze the effect of the hazardous components in ground water on the engineering properties of shotcrete. The uniaxial compressive strength test, XRD, SEM were conducted to evaluate the durability and corrosion of shotcrete.

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Preparation of Tenoxicam Salt with Ethanolamine to Enhance the Percutaneous Absorption (테녹시캄의 피부 흡수율을 증진시키기 위한 에탄올아민염의 제조)

  • Gwak, Byung-Tae;Chun, Myung-Kwan;Choi, Hoo-Kyun
    • Journal of Pharmaceutical Investigation
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    • v.36 no.3
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    • pp.169-174
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    • 2006
  • The aim of this work was to prepare tenoxicam-ethanolamine salt with improved physicochemical properties for transdermal application. Tenoxicam-ethanolamine salt was prepared in methylene chloride and its physicochemical properties were investigated by DSC and FT-lR. The broad peak of tenoxicam around 3600-3200 $cm^-1$ was shifted to lower wavenumber and more broadened. The characteristic endothermic melting peak of tenoxicam appeared at $223^{\circ}C$. The melting peak of tenoxicam-ethanolamine salt was shifted to $159^{\circ}C$. In contrast to relatively small difference in the partition coefficients of tenoxicam and the tenoxicam-ethanolamine salt, large difference in aqueous solubility was observed. $Crovol^{\circledR}$ PK4O (PEG-12 palm kernel glycerides) provided the highest skin flux for both compounds. The order of the enhancing effect of the various vehicles tested was similar for tenoxicam and tenoxicam-ethanolamine salt, which indicated that their enhancing mechanism for tenoxicam and tenoxicam-ethanolamine salt is similar. Tenoxicam-ethanolamine salt had a higher skin flux than tenoxicam by 1.2- to 31.7-fold, depending on the vehicles used. It is suggested that the vehicles with medium HLB value, 1 double bond, and lower ethylene oxide chain length have a better ability to modify the permeability of the stratum corneum and to promote the effective penetration of tenoxicam and tenoxicam-ethanolamine salt.

Changes in IR Spectra of Ambers with Accelerated Aging (가속열화 시 호박 IR 특성의 경시적 변화)

  • Park, Jongseo;Lim, Yujin
    • Journal of Conservation Science
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    • v.28 no.3
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    • pp.247-256
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    • 2012
  • Amber has been used as gemstones and artifacts from the period of the Three Kingdoms or earlier, which are discovered in the process of excavation now. It is, however, very difficult to discuss the importing route and circulation of amber because there are no informations available on the provenance. In this study, we acquired the IR spectra of ambers originating from 5 different locations. We also monitored the change of characteristic IR peaks by artificially aging the ambers under heat, light and heat with oxygen, respectively. As the aging proceeded, the intensity of C=O band and O-H band increased, however, the bands related with C=C bond decreased. There needed some modifications in the discerning scheme because some peak disappeared with aging; yet, it was still possible to discern different ambers largely. Therefore, it is expected that the scheme can be used practically by appraising its applicability to the real amber relics excavated.

Case Study for the Communication Method of Information Design Type Advertising (정보디자인형 광고의 커뮤니케이션 기법에 관한 연구)

  • Kim, Jong-Min;Park, Han-Sol
    • The Journal of the Korea Contents Association
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    • v.17 no.11
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    • pp.90-101
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    • 2017
  • This study will analyze that the meaning and the characteristic of Information design type advertising. This study research the advertisement and Information with the issue and explore Information design type advertising samples by doing an in-depth analysis with an expert group and an inexpert group. It attracts customers visualizing sensational information and data as information design technique. It can be classified in to Manual type ad, Identity type ad, Data visualizing type ad. The communication formula of it goes through the keywords: Attention, Curation, Study, and these Curation and Study are new steps which didn't exist before in consumer behavior model. Information used in it comes from common sense or storytelling made by imagination, but there is no example of using false information distorting truth. Not exaggeration and falsehood, interesting which based on confidence creates a bond of sympathy: period time.

Relationship Marketing Factors, Relationship Quality, and Store Loyalty in Retail Specialty Stores (소매전문점에서의 관계마케팅요인과 관계품질 그리고 점포충성도와의 관계)

  • Park, Myung-Ho;Jung, Jung-Il
    • Journal of Distribution Research
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    • v.11 no.4
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    • pp.97-124
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    • 2006
  • This study investigates the relationship between the relationship marketing factors, relationship quality and store loyalty in retail specialty stores. The customization of a retail specialty store was found to be having a larger effect on relationship quality than other factors such as expertise, bonding and communication and the moderating effects of customer characteristic was found be having a larger effect on relationship quality all factors except to communication. The result of this study has some practical implications. First of all, the customization strategy for individual customers is needed because customers trusted employees who provide a customized service more. Second, the employees' expertise is important to obtain the trust of customers. Third, the findings of the study showed that the communication with employees did not affect the trust. Rather, customers more often want price discounts, useful information, other benefits related to transactions. The communication is also necessary to bond a strong relationship with customers, as well as to respond customer's requests immediately Fourth, the marketing managers of the store have to effectively manage the customer relationship with the special consideration to the customer's gender, transaction experience, and variety seeking disposition.

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The Adsorption of Alkyl Aldehydes on Cations Supported by Layer Silicate. Complex Formation Theory (Layer Silicate에 지지된 양이온상에서의 알킬알데히드의 흡착기구. 착물형성 이론)

  • Kim Jong Taik;Sohn Jong Rack
    • Journal of the Korean Chemical Society
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    • v.18 no.3
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    • pp.180-188
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    • 1974
  • Adsorption mechanism of alkyl aldehydes, acetaldehyde, acrolein, and crotonaldehyde on cations supported by layer silicates was studied by means of IR spectroscopy and X-ray. An analysis of four characteristic split bands in the region of $1720∼1580㎝^{-1}$ was made. The carbonyl stretching band which shifted about $130㎝^{-1}$ to lower frequencies was observed only for $Ni^{2+}$ and Al^{3+}$ but slightly with $Ca^{2+}$ at high sample temperature and was attributed to >C=O…M complex formation. A sharp band which appeared as a shoulder at 1722 for acetaldehyde and 1690 for acrolein and crotonaldehyde was responsible for the interaction of carbonyl with surface hydroxyl. The second broad band which appeared at about 1710~1660 was responsible for hydrogen bonding between carbonyl oxygen and cationic hydroxyl group. The third band which appeared at about 1640~1660 was attributed to induced >C=C< double bond due to the strong carbonyl interaction. This was supported by the interlamellar spacings obtained by X-ray diffractometry.

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Material and Geometrical Noninear Analysis of Reinforced Concrete Columns under Cyclic Loading (반복하중을 받는 철근콘크리트 기둥부재의 재료 및 기하적인 비선형 해석)

  • 김운학
    • Journal of the Earthquake Engineering Society of Korea
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    • v.3 no.1
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    • pp.55-66
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    • 1999
  • This paper presents an analytical prediction of the hysteresis behavior of reinforced concrete long column with rectangular section under the cyclic loading state. The mechanical characteristic of cracked concrete and reinforcing bar in concrete has been modeled, considering the bond effect between reinforcing bar and concrete, the effect of aggregate interlocking at crack surface and the stiffness degradation after the crack has taken place. The strength increase of concrete due to the lateral confining reinforcement has been also taken into account to model the confined concrete. The formulation of these models for concrete and reinforcing bar has been based on the smeared crack concept that the stress-strain relationship of reinforced concrete element would be defined using the average values. In addition to the material nonlinear properties, the algorithm for large displacement problem that may give an additional deformation has been formulated using total Lagrangian formulation. The analytically predicted behavior was compared with test result and they showed good agreement in overall behavior.

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Antibiotics from Mushrooms (버섯의 항생물질(抗生物質))

  • Hwang, Byung-Ho
    • Journal of Forest and Environmental Science
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    • v.22 no.1
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    • pp.83-100
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    • 2006
  • Antibiotics which produced by mushrooms discovered for last 40 years were described. Any antibiotic has not been used as infectious disease remudy but will be used as physiological active substance in near future. The antibiotic of mushrooms have not been published much in papers and do not have various finds of structures, compared to those of Streptomyces. Triple bond having compounds, terpenoid compounds aromatic compounds and some other compound have been known. These compounds are not dissolved well in water and mainly fat-soluble, except for cordycepin. Also, they are generally neutral, and some of them are acidic and almost none of them are basic compounds. However, acetylene and terpenoid compounds are the characteristic compounds of mushroom, and are not found in other microorganisms and plants. Especially, there are various terpenoid compounds in mushrooms. These metabolites of mushrooms were not used as antibiotic, but are interested as physiological active substance, such as enzyme inhibitor and immunomodulator. To promote studying on the antibiotics of mushroom, new screening methods must be developed, because strain belonged to the different genus produces different antibiotics, even though mushrooms belonged to the same genus and species. It is also known that mushrooms collected in different areas produce different antibiotics. Now, it is difficult to separate each pure compound from mushroom. It is important to find mushrooms which is impossible to cultivate artificially, or grow in the back land where is difficult to collect. Thousands of mushrooms grow on earth now, so that which species will be screened if not known. The biochemical and mycological study for usability of the metabolites of mushrooms is thought, as one of the important research areas, must be performed.

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States, Behaviors and Cues of Infants (영아의 상태, 행동, 암시)

  • Kim, Tae-Im
    • Korean Parent-Child Health Journal
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    • v.1
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    • pp.56-74
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    • 1998
  • The language of the newborn, like that of adults, is one of gesture, posture, and expression(Lewis, 1980). Helping parents understand and respond to their newborn's cues will make caring for their baby more enjoyable and may well provide the foundation for a communicative bond that will last lifetime. Infant state provides a dynamic pattern reflecting the full behavioral repertoire of the healthy infant(Brazelton, 1973, 1984). States are organized in a predictable emporal sequence and provide a basic classification of conditions that occur over and over again(Wolff, 1987). They are recognized by characteristic behavioral patterns, physiological changes, and infants' level of responsiveness. Most inportantly, however, states provide caregivers a framework for observing and understanding infants' behavior. When parents know how to determine whether their infant is sleep, awake, or drowsy, and they know the implications, recognition of states has for both the infant's behavior and for their caregiving, then a lot of hings about taking care of a newborn become much easier and more rewarding. Most parents have the skills and desire to do what is best for their infant. The skills 7373parents bring to the interaction are: the ability to read their infant's cues: to stimulate the baby through touch, movement, talking, and looking at: and to respond in a contingent manner to the infant's signals. Among the crucial skills infants bring to the interaction are perceptual abilities: hearing and seeing, the capacity to look at another for a period of time, the ability to smile, be consoled, adapt their body to holding or movement, and be regular and predictable in responding. Research demonstrates that the absence of these skills by either partner adversely affects parent-infant interaction and later development. Observing early parent-infant interactions during the hospital stay is important in order to identify parent-infant pairs in need of continued monitoring(Barnard, et al., 1989).

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A Study on the Improvement of Coloring in Dye-sensitized Solar Cell (염료감응형 태양전지의 착색 특성 개선 연구)

  • Seo, Hyun-Woong;Kim, Mi-Jeong;Son, Min-Kyu;Lee, Kyoung-Jun;Hong, Ji-Tae;Kim, Hee-Je
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.11a
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    • pp.297-300
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    • 2007
  • In this study, we have attempted a new method to enhance the coloring of dye on the $TiO_2$ surface in the dye sensitized solar cell. In the conventional coloring process in a dye sensitized solar cells, dye is absorbed by the covalent bond between TiO2 and dye molecule while the photo-electrode coated with $TiO_2$ layer is soaked in dye solution for about 12-24 hours. But this process takes long time, so we have researched more effective and faster way than the conventional process by applying electric field. Three kinds of electric power such as direct voltage, alternating voltage and pulse voltage were applied to the transparent conducting oxide during the coloring process. As a result, we achieved improved power, fill factor and efficiency of dye-sensitized solar cell in case of applying direct voltage and pulse voltage. In contrast, alternating voltage tend to reduce the dye adsorption on the $TiO_2$ surface and hence the efficiency. We measured the absorption spectra of dye by UV-VIS spectrophotometer before and after soaking the $TiO_2$ in the dye and found no characteristic change in the dye was observed. In this study, we researched on shortening time of coloring process which spent much time in the whole process.

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