Park, Hye-Yang;Oh, Nam-Sik;Lee, Keun-Woo;Lee, Ho-Yong
The Journal of Korean Academy of Prosthodontics
/
v.35
no.4
/
pp.647-661
/
1997
The resin modified glass ionomer cements(RMGICs) have been used for years since 1989. Recently it has been developed for luting of fixed restorations. To evaluate the bond strength and marginal leakage of RMGICs for luting usage, the 80 extracted human molars which had uniform area of exposed dentin were cemented with 3 types of RMGICs(Fuji Duet, Advance, Vitremer), a conventional Glass Ionomer Cement(GIC-Fuji I), and a resin cement (Panavia 21) to base metal alloy(Ni-Cr-Be). After thermocycling the specimens were immersed in basic fuschin dye for measuring marginal leakage. The shear bond strength was measured with Instron and the maximum dye penetration was measured to 0.1mm. The types of fractured patterns were determined with stereoscope(${\times}7.5$). The results are as follows. 1. The difference between 3 RMGICs and a conventional GIC in shear bond strength was not statistically significant. It seemed that RMGICs had lower shear bond strength than resin cement. (p<0.01) 2. The mean scores of marginal leakage had no significant difference between the resin cement and 3 RMGICs but it was much higher in conventional GIC than the RMGICs (p<0.05) 3. It was determined that the manufacturer and the methods of dentin pretreatment determined the pattern of fracture surfaces and the frequency of adhesive failure between teeth and 3 RMGICs standed as in following order - Vitremer, Advance, Fuji Duet. (p<0. 01) When the fracture pattern was analyzed, it could be said that the materials and the method of dentin pretreatment have much effect on bonding states. This means that the dentin bonding agents should be improved. But the limited products in this experiment can not evaluate the physical properties of the entire RMGICs. Therefore a further study which can evaluate various RMGICs should be in progress to develope better cements.
The reaction mechanisms of dry cleaning with UV-excited chlorine radical for Zn, Fe and Ti trace contaminants on the Si wafer have been studied by SEM, AFM and XPS analyses in this work. The patterned Zn, Fe and Ti films were deposited on the Si wafer surface by thermal evaporation and changes in the surface morphology after dry cleaning with $Cl_2$and UV/$Cl_2$at $200^{\circ}C$ were studied by optical microscopy and SEM. In addition, changes in the surface roughness of Si wafer with the cleaning was observed by AFM. The chemical bonding states of the Zn, Fe and Ti deposited silicon surface were observed with in-line XPS analysis. Zn and Fe were easily cleaned in the form of volatile zinc-chloride and iron-chloride as verified by the surface morphology changes. Ti which forms involatile oxides was not easily removed at room temperature but was slightly removed by UV/$Cl_2$at elevated temperature of $200^{\circ}C$. It was also found that the surface roughness of the Si wafer increased after $Cl_2$and UV/$Cl_2$cleaning. Therefore, the metallic contaminants on the Si wafer can be easily removed at lower temperature without surface damage by a continuous process using wet cleaning followed by UV/$Cl_2$dry cleaning.
Jo, Han-Young;Kim, Tae-Heon;Kim, Ho;Jeong, Han-Sol;Lee, Chang-Hyun;Lee, Gwang-Gyu
Journal of Physiology & Pathology in Korean Medicine
/
v.22
no.2
/
pp.357-364
/
2008
Mylabris is the dried body of the chinese blister beetle. The species used in medicine are Mylabris phalerata and M. cichorii. In recent studies, it has been found that Mylabris possesses antitumor properties, increases the number of leukocytes, and has irritant effects on the urinary organs. The crude extracts of Mylabris have been noted for their highly irritant action and other traditional uses of Mylabris include treatment of poor local blood circulation. The active constituent of Mylabris is cantharidin. The chemical is notable for its vesicant properties, but with severe side effects such as nephrotoxicity. This experiment examined the effect of extracts and fractions, obtained from Mylabris phalerata Pall. on hair growth activity of the C57BL/6N mice after topical application to skin. First, we examined the effect of an extracts, obtained from the alcohol extracts of dried Mylabris phalerata Pall. on hair growth activity of the C57BL/6N mice after topical application to skin. Second, we examined on hair growth activity of the cantharidin fraction of Mylabris phalerata Pall. compared to the control and 1% minoxidil groups. Third, we investigated the number of hair follicle and mast cells after topical application of extracts of Mylabris phalerata Pall. to skin for 16 days. The results were as follows: Hair growth effect from the extracts of Mylabris phalerata Pall.(0.312%) was observed in 80% of mice whose hair had been removed in 13 days. Hair growth effect from the extract of Mylabris phalerata Pall.(0.312 and 0.625%) and 1% minoxidil group was observed in 100% of mice whose hair had been clipped in 20 days. Hair growth effect from the cantharidin fraction(0.5%) and water fraction(0.5%) of Mylabris phalerata Pall. was observed in 100% of mice whose hair had been clipped in 24 days. The hair growth effect on the cantharidin fraction(0.125%) was observed to be strong compared with the minoxidil(3%) group, commercial hair growth agents, in mice whose hair had been clipped in 19 days. In the spontaneous alopecia mice model, the hair growth effect from the cantharidin fraction (0.125%) was observed to be strong as compared with the states before the 13 days experiment. These experiments suggest that extracts and fractions of Mylabris phalerata Pall. may stimulate the topical hair growth activity in low doses.
To compare the photocatalytic performances of titania for purification of waste water according to applied voltages and doping, $TiO_2$ films were prepared in a 1.0 M $H_2SO_4$ solution containing $NH_4F$ at different anodic voltages. Chemical bonding states of F-N-codoped $TiO_2$ were analyzed using surface X-ray photoelectron spectroscopy (XPS). The photocatalytic activity of the co-doped $TiO_2$ films was analyzed by the degradation of aniline blue solution. Nanotubes were formed with thicknesses of 200-300 nm for the films anodized at 30 V, but porous morphology was generated with pores of 1-2 ${\mu}m$ for the $TiO_2$ anodized at 180 V. The phenomenon of spark discharge was initiated at about 98 V due to the breakdown of the oxide films in both solutions. XPS analysis revealed the spectra of F1s at 684.3 eV and N1s at 399.8 eV for the $TiO_2$ anodized in the $H_2SO_4-NH_4F$ solution at 180 V, suggesting the incorporation of F and N species during anodization. Dye removal rates for the pure $TiO_2$ anodized at 30 V and 180 V were found to be 14.0% and 38.9%, respectively, in the photocatalytic degradation test of the aniline blue solution for 200 min irradiation; the rates for the F-N-codoped $TiO_2$ anodized at 30 V and 180 V were found to be 21.2% and 65.6%, respectively. From the results of diffuse reflectance absorption spectroscopy (DRS), it was found that the absorption edge of the F-N-codoped $TiO_2$ films shifted toward the visible light region up to 412 nm, indicating that the photocatalytic activity of $TiO_2$ is improved by appropriate doping of F and N by the addition of $NH_4F$.
The Ulsan Fe-W deposit, which can be classified as a calcareous skarn deposit, is represented by ore pipe consisting principally of magnetite and lesser amounts of scheelite with minor sulphides, sulphosaits, arsenides, sulpharsenides, etc. At Ulsan mine, metasomatic processes of skarn growth may be divided broadly into two stages based on the paragenetic sequence of calc-silicate minerals and their chemical composition; early and late skarn stages. Early stage has started with the formation of highly calcic assemblages of wollastonite, diopsidic clinopyroxene and nearly pure grossular, which are followed by the formation of clinopyroxenes with salite to ferrosalite composition and grandite garnets with intermediate composition. Based on these calc-silicate assemblages, the temperatures of early skarn formations have been in the ranges of $550^{\circ}$ to $450^{\circ}$. The calc-silicate assemblages formed during the earlier half period of late skarn stage show the enrichment of notable iron and slight manganese, and the depletion of magnesium; clinopyroxenes are hedenbergitic, and grandite garnets are andraditic. The formation temperatures during this skarn stage are inferred to have been in the range of $430^{\circ}$ to $470^{\circ}C$ at low $X_{CO_2}$ by data from fluid inclusions of late andraditic garnets. The later half period of late skarn stage is characterized by the hydrous alteration of pre-existing minerals and the formation of hydrous silicates. The main iron-tungsten mineralization representing prominent deposition of magnetite immediately followed by minor scheelite impregnation has taken place at the middle of early skarn stage, while complex polymetallic mineralization has proceeded during and after the late skarn stage. Various metals and semimetals of Fe, Ni, Co, Cu, Zn, As, Mo, Ag, In, Sn, Sb, Te, Pb and Bi have been in various states such as native metal, sulphides, arsenides, sulphosaits, sulpharsenides and tellurides.
While the oxygen content of gasoline for automobiles in Korea is regulated to less than 2.3 weight %, European and World-Wide Fuel Charter (WWFC) regulate it to less than 2.7 weight %. The oxygen content of oxygen-containing materials increases the octane number of the fuel due to the secondary combustion in the internal combustion engine. It has been reported to be effective in reducing emissions, such as CO, HC, which is caused by incomplete combustion. Before 2000s in the United States and Europe, there has been many researches about vehicle application of the changes in oxygen content of gasoline. However, there are not many domestic researches which reflect the improvement of the fuel quality and automotive technology. In this study, fuels of three different oxygen contents were applied to GDI and MPI engines. As a result, the changes of fuel consumption and emission gas were very similar depends of the oxygen content changes. The PN in GDI engine was decreased as the oxygen content was increased.
Journal of Korean Society for Geospatial Information Science
/
v.17
no.3
/
pp.3-12
/
2009
Soil is one of the Earth's most important resources. There are many differences among the soils of plains.like and hilly terrains, and therefore, accurate and comprehensive information on soil is essential for optimum and sustainable soil utilization. However, information on the soil of the hilly terrains of the Eastern Ghats of Tamil Nadu, India, is limited or absent. In the present study, Kolli hill, one among the hills of the Eastern Ghats, was soil.inventoried and mapped using a ground survey and remote sensing. Soil samples were collected and their physico.chemical properties analyzed according to the United States Department of Agriculture (USDA) standards. The soils were classified up to the family level. As a result of this study, 30 soil series belonging to ten sub.groups of five great groups and three sub.orders and orders each, were identified (classified to the family level) and mapped. Entisols, Inseptisols and Alfisols were the three orders, among which Entisols was the major one, occupying 75% of the area. Among the five great groups, Ustorthents occupied majority of the area (73%). Lithic Ustorthents and Typic Ustorthents were the two major sub.groups, occupying 40% and 26% of the total area, respectively. The present soil resource mapping of the Eastern Ghats of Tamil Nadu is a pioneer study, which yielded valuable information on the soil in this region.
In this study, it was analysed physical characteristics, TS, moisture, C/N ratio, leaching test, and element analysis in landfill wastes of 10 years old without landfill pretreatment. The Organic material content was 7.2%~23.5% and soil was the main inorganic materials which it's rate was 54.1%~71.0%, in landfill wastes. The results of TS, VS, and moisture were represented 51.5%~68.1%, 23.6%~56.1%, 32.0%~48.4%, respectively. The analysis of hazardous materials did not indicate Hg, $Cr^{+6}$, CN, Organic Phosphorus, TCE and PCE, however the Pb of leaching materials showed 0.023~0.092 mg/L, which was the highest. As the result of the element analysis, C was 47.74%~56.72%, N was 4.09%~9.92%, the C/N ratio was 5.76~12.57 and the result of soils around landfill was the highest heavy material, Pb, 2.465 mg/kg~10.251 mg/kg. The objectives of this paper are to investigate states, stabilization of these closed landfills and to gain suitable data for post-closure care using some parameters through analysis of landfill environment.
Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
/
2008.06a
/
pp.169-169
/
2008
To keep pace with scaling trends of CMOS technologies, high-k metal oxides are to be introduced. Due to their high permittivity, high-k materials can achieve the required capacitance with stacks of higher physical thickness to reduce the leakage current through the scaled gate oxide, which make it become much more promising materials to instead of $SiO_2$. As further studying on high-k, an understanding of the relation between the etch characteristics of high-k dielectric materials and plasma properties is required for the low damaged removal process to match standard processing procedure. There are some reports on the dry etching of different high-k materials in ICP and ECR plasma with various plasma parameters, such as different gas combinations ($Cl_2$, $Cl_2/BCl_3$, $Cl_2$/Ar, $SF_6$/Ar, and $CH_4/H_2$/Ar etc). Understanding of the complex behavior of particles at surfaces requires detailed knowledge of both macroscopic and microscopic processes that take place; also certain processes depend critically on temperature and gas pressure. The choice of $BCl_3$ as the chemically active gas results from the fact that it is widely used for the etching o the materials covered by the native oxides due to the effective extraction of oxygen in the form of $BCl_xO_y$ compounds. In this study, the surface reactions and the etch rate of $Al_2O_3$ films in $BCl_3/Cl_2$/Ar plasma were investigated in an inductively coupled plasma(ICP) reactor in terms of the gas mixing ratio, RF power, DC bias and chamber pressure. The variations of relative volume densities for the particles were measured with optical emission spectroscopy (OES). The surface imagination was measured by AFM and SEM. The chemical states of film was investigated using X-ray photoelectron spectroscopy (XPS), which confirmed the existence of nonvolatile etch byproducts.
[ $AB_2X_4$ ](A, B=Transition Metal, X=O, S, Se) are cubic spinel normal ferrimagnets, in which M ions occupy the tetrahedral sites and Cr ions occupy the octahedral sites. Recently, they have been investigated for behaviour of B site ions and A-B interaction. Polycrystalline $[Co_{0.9}Zn_{0.1}]_A[Cr_{1.98}{^{57}Fe_{0.02}}]_BO_4$ compound was prepared by wet-chemical process. The ferrimagnetic transition was observed around 90K. $M\"{o}ssbauer$ absorption spectra at 4.2K show that the well-developed two sextets are superposed with small difference in hyperfine fields($H_{hf}$). The hyperfine fields of $CoCr_{1.98}{^{57}Fe_{0.02}}O_4$ and $Co_{0.9}Zn_{0.1}Cr_{1.98}{^{57}Fe_{0.02}}O_4$ were determined to be 488, 478 kOe and 486, 468 kOe, respectively. We notice that the one of the magnetic hyperfine field values changes with Zn ion substitution. These results suggest the incommensurate states and spin-reorientation temperature($T_S=18K$) changes with Zn ions substitution below spin-reorientation temperature($T_S=28K$) of $CoCr_{1.98}{^{57}Fe_{0.02}}O_4$
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.