• 제목/요약/키워드: Ivory

검색결과 104건 처리시간 0.026초

조선시대 조적용 석회의 소성 성능과 모르타르의 물성에 대한 실험 연구 (An Experimental Study on the Firing Performance and Property of Lime Mortar for Building in Joseon Dynasty)

  • 이상옥;정광용
    • 건축역사연구
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    • 제25권3호
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    • pp.37-45
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    • 2016
  • This study was to investigate the firing method of limestone in Joseon Dynasty, and analyze the physical chemical properties of lime mortars in Joseon Dynasty. This study was to manufacture and evaluate the firing experiment and mortar of Limestone by each sort in order to reproduce the traditional lime mortars in Joseon Dynasty, and investigate the behavior to improve physical properties according to the firing method of Limestone. This study has found out that there were screening criteria and standard of appropriate firing temperature about the Limestone in Joseon Dynasty. Accordingly, this study was to improve its strength through various additives and mixture. In particular, in case of Limestone, the black and blue Limestone were preferred, and most of domestic Limestones were low grade Limestone including the clay and took ivory white or blue with low whiteness. This study has shown that the low grade Limestone was mined by the surface mining compared with the high grade Limestone as underground mining method, and could be used because it was easy to mine relatively and there was possibility that Natural Hydraulic Lime(NHL) was used with the traditional lime mortars in Joseon Dynasty.

백제시대의 목공예 연구 (A Study on Woodcraft in Baekje)

  • 조숙경
    • 한국가구학회지
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    • 제25권2호
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    • pp.139-147
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    • 2014
  • This paper researched the woodcraft in the Baekje kingdom since the study on the Baekje furniture has not been established due to the absence of the artifacts or remains related to the furniture in the Baekje period. Accordingly, the study focused on the excavated Baekje wooden products and wood crafts on the basis of ancient documents and investigated the ancient documents supposedly related to the Baekje furniture: The Chronicles of the Three States and Japan Scribe. As the result of the study, it could be summarized as follows. First of all, the woodcraft materials were wood, whagak, ivory, silver, gold and they were domestic or imported. Secondly, the woodcraft was finished naturally or lacquered with black or red color or varnishing with lacquer. Thirdly, the kinds of furniture used in the Baekje were a desk, a small portable dinning table, a table and folding stool. Even though there has been no heritage of the Baekje furniture and woodcraft and it is difficult to explain the characteristics or give an example of the Baekje furniture in detail, this study seems to be significant now that it researched the documents and related artifacts or remains which could give some hints or hypothesis of the furniture and woodcraft in the Baekje. What is more, there have been no sound studies on the Baekje furniture.

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흑연 함침법에 의한 흑색 지르코니아의 제조 및 특성분석 (Preparation and Characterization of Black Color Zirconia by Impregnation Method Used by Graphite)

  • 이광호;안종필;박주석;이용석;이병하
    • 한국세라믹학회지
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    • 제46권4호
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    • pp.379-384
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    • 2009
  • Zirconia is widely used for structural materials in machinery due to its superior properties, such as high strength, high hardness, and high toughness. Zirconia generally has ivory or white color. Therefore many studies are performed for diversification of zirconia color, in order to be widely uitilized for decoration and machine parts which need distincfive color. In this study, graphite is used to prevent structural defect, to maintain superior properties, and to develop black color of zirconia by impregnation method. As specimen was impregnated at $1600^{\circ}C$ for 2 h, bending strength is 1221 MPa, density is $6.01\;g/cm^3$, hardness is 10.1 GPa, absorption coefficient is 0%, transmittance is Fail, chromaticity is 54. The results indicate that black zirconia has enough properties to be adopted as mechanical parts. Optimum impregnation time is 2 h for various observations.

천연 오미자 추출물의 약리, 화학적 특성 및 분석 (A study on the Pharmaceutical & Chemical Characteristics and Analysis of Natural Omija Extract)

  • 성기천
    • 한국응용과학기술학회지
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    • 제28권3호
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    • pp.290-298
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    • 2011
  • Natural Omija belongs to magnoliaceae was known to possess natural odor, taste, color, and various pharmaceutical & chemical characteristics. Omija extraction was extracted using ethanol as a solvent. Omija extract showed a light red-violet color of viscous liquid state. Some conclusions from the result of characteristic experiment were obtained as follows. From the result of antimicrobial experiment, occurrence of staphylococuss aureus and aspergillus niger as microbes was decreased according to the passage of time. This phenomenon could know that Omija component is affected to antimicrobial effect. From the result of dye experiment, fiber dyeing showed with some ivory color after dyed to cotton and silk. This phenomenon could know that Omija component is affected to dyeing effect from observation of scanning electron microscope(SEM). From the result of instrument analysis, inorganic components of K(107.30ppm), Na(2.110ppm), Ca(0.935ppm), Mg(0.891ppm), Li(0.270ppm) etcs from Omija were detected with ICP/OES, and aromatic components of benzene(10.808), a-pinene(13.996), phenol(14.183), ${\beta}$-terpene(15.840), a-terpinolene(17.616) etcs from Omija were also detected with GC/MSD.

전부도재관에 사용되는 레진시멘트의 색안정성에 관한 연구 (THE STUDY ON THE COLOR STABILITY OF RESIN CEMENT USED IN ALL CERAMIC CROWN)

  • 이태희;이영수;박원희
    • 대한치과보철학회지
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    • 제42권1호
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    • pp.41-48
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    • 2004
  • Statement of problem : The Cement as well as restoration required esthetics for making natural color restoration. Purpose : The purpose of this research is to evaluate color stability of restoration intermediated by resin cement which is used for cementation of all ceramic crown. Material and method : After making Empress 2 ingot into the size of $10mm{\times}10mm{\times}1mm$ according to indication, it glazed and made 48 Empress 2 blocks. Three kinds of resin cement(Rely-X, Variolink 2, Choice) having same shade cemented between Empress 2 blocks and Ivory shade tiles and made 48 specimens in the thickness of $30{\mu}m$ and $80{\mu}m$. After measureing color difference using spectorphotomenter, the result of this study were as follows. Results : The color difference of resin cement used in experiment increased in the order Rely-X, Variolink 2. As the thickness of cement increases, the color difference of all kinds of cement found statistically sifnificant difference but, this result is clinically acceptable. Conclusion : More resarch would have to be done in order to decrease the color difference as cement's thickness.

대학의 영어강의 확대에 대한 비판적 논의 (A Critical Approach on the Extension of Lecture in English at Colleges)

  • 김달효
    • 수산해양교육연구
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    • 제22권1호
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    • pp.38-51
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    • 2010
  • The purpose of this study was to criticize (through available documents) the lecture in English at colleges. It is necessary that a study of English is emphasized in the era of internationalization. But, the indiscreet extension of lecture in English without consideration of the purpose, principle, and philosophy of college's education needs reflective thinking. This study criticized four dimensions, in other words the effectiveness of lecture in English, criteria of internationalization and college's competition of lecture in English, social inequality of lecture in English, and the harmfulness in the value of Korean language of lecture in English. First, most researches expressed the indiscreet extension of lecture in English was not effective in both students and professors. Second, many scholars and agencies on the internationalization and college's competition excluded the lecture in English as criteria. Third, the indiscreet extension of lecture in English had the possibility of social inequality. And fourth, the indiscreet extension of lecture in English had harmfulness in the value of Korean language and Korean's thought. College's education is an ivory tower in society. So, colleges should discard the thought that extension of lecture in English is the best way. Colleges should keep the purpose, principle, and philosophy of college's education.

한국산 미기록종 Russula eburneoareolata Hongo (상아무당버섯)의 보고 (Note on the New Record of Russula eburneoareolata Hongo in Korea)

  • 신광수
    • 한국균학회지
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    • 제38권2호
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    • pp.197-198
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    • 2010
  • 2006년 7월25일 국립공원 계룡산 상신리 지역의 활엽수림에서 채집한 무당버섯인 R. eburneoareolata Hongo의 형태학적 특징 및 생태학적 특성을 기초로 하여 상아무당버섯으로 명명하였다. 본 종의 자실체는 중형이며, 갓은 4-9 cm의 크기이며 성숙하면 표면이 갈라져 상아색 돌기 모양이 나타난다. 주름살은 조밀하며 짙은 크림색이며 자루는 길이가 3-6 cm, 두께가 12-20mm 정도이다. 포자는 타원형이며 표면에 사마귀모양의 돌기가 가는 띠로 연결되어 분포한다. 크기는 $7-8{\times}6-7\;{\mu}m$이다. 담자기는 크기가 $35-40{\times}10-11\;{\mu}m$ 정도이며 4개의 담자포자가 달린다. 낭상체는 반원통형 또는 방망이 모양으로 끝부분이 약간 뾰족하다.

A case of breast sparganosis

  • Sim, Seo-Bo;You, Jai-Kyung;Lee, In-Young;Im, Kyung-Il;Young, Tai-Soon
    • Parasites, Hosts and Diseases
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    • 제40권4호
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    • pp.187-189
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    • 2002
  • A 29-year-old Korean woman visited the Department of Surgery in MizMedi Hospital with a palpable itching mass on the right breast that had existed for the past 7 months. She had no history to eat either frogs or snakes, but had the history of drinking impure water. Sonography revealed a serpiginous hypoechoic tubular structure associated with partial fat necrosis in breast parenchymal layer and subcutaneous fat layer. It also revealed oval cystic lesions. At operation, an ivory white opaque ribbon-like worm that measured 16.5 cm in length and 0.5 cm in width was extracted. Anti-sparganum specific serum IgG level in the patient's serum (absorbance = 0.71), measured by ELISA, was found to be significantly higher than those of normal controls (cut off point = 0.21) . Sonography and ELISA appear to be helpful to diagnose sparganosis. Breast sparganosis is rarely found throughout the world.

A Human Case of Lumbosacral Canal Sparganosis in China

  • Fan, Jian-Feng;Huang, Sheng;Li, Jing;Peng, Ren-Jun;Huang, He;Ding, Xi-Ping;Jiang, Li-Ping;Xi, Jian
    • Parasites, Hosts and Diseases
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    • 제59권6호
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    • pp.635-638
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    • 2021
  • In this study, we intended to describe a human case of lumbosacral canal sparganosis in People's Republic of China (China). A 56-year-old man was admitted to Xiangya Hospital Central South University in Changsha, Hunan province, China after having an experience of perianal pain for a week. An enhancing mass, a tumor clinically suggested, was showed at the S1-S2 level of the lumbosacral spine by the examination of magnetic resonance imaging (MRI) with gadolinium contrast. The patient was received the laminectomy from S1 to S2, and an ivory-white living worm was detected in inferior margin of L5. In ELISA-test with cerebrospinal fluid (CSF) and serum samples, anti-sparganum antibodies were detected. He had a ingesting history of undercooked frog meat in his youth. By the present study, a human case of spinal sparganosis invaded in lumbosacral canal at the S1-S2 level was diagnosed in China. Although the surgical removal of larvae is known to be the best way of treatment for sparganosis, we administered the high-dosage of praziquantel, albendazole and dexamethasone to prevent the occurrence of another remain worms in this study.

Impact resistance efficiency of bio-inspired sandwich beam with different arched core materials

  • Kueh, Ahmad B.H.;Tan, Chun-Yean;Yahya, Mohd Yazid;Wahit, Mat Uzir
    • Steel and Composite Structures
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    • 제44권1호
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    • pp.105-117
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    • 2022
  • Impact resistance efficiency of the newly designed sandwich beam with a laterally arched core as bio-inspired by the woodpecker is numerically investigated. The principal components of the beam comprise a dual-core system sandwiched by the top and bottom laminated CFRP skins. Different materials, including hot melt adhesive, high-density polyethylene (HDPE), acrylonitrile butadiene styrene (ABS), epoxy resin (EPON862), aluminum (Al6061), and mild carbon steel (AISI1018), are considered for the side-arched core layer of the beam for impact efficiency assessment. The aluminum honeycomb takes the role of the second core. Contact force, stress, damage formation, and impact energy for beams equipped with different materials are examined. A diversity in performance superiority is noticed in each of these indicators for different core materials. Therefore, for overall performance appraisal, the impact resistance efficiency index, which covers several chief impact performance parameters, of each sandwich beam is computed and compared. The impact resistance efficiency index of the structure equipped with the AISI1018 core is found to be the highest, about 3-10 times greater than other specimens, thus demonstrating its efficacy as the optimal material for the bio-inspired dual-core sandwich beam system.