• Title/Summary/Keyword: Ti-mesh

Search Result 75, Processing Time 0.024 seconds

Alveolar Ridge Augmentation Using Titanium Reinforced Goretex (TRG) and Titanium Mesh in Severe Alveolar Bone Loss Area: Case Report (심하게 흡수된 치조제에 Titanium 강화 Gore-Tex (TRG) 및 Titanium Mesh로 수직적 골증대술을 실시한 증례보고)

  • Kim, Won-Jik;Yoon, Kyung-Sun;Hong, Su-Ryun;Choi, Jin-Kyung;Lee, Yong-Uk;Kim, Dong-Suk;Hyun, Jong-Oh;Cho, Hyo-Won;Choi, Ji-Hye;Jung, Tae-Woong;Bae, Yoon-Ki;Kwon, Sun-Kyu;Choi, Hyun-Joon;Lee, Hyun-Su;Yang, Su-Nam
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.33 no.1
    • /
    • pp.66-72
    • /
    • 2011
  • A severely vertical resorbed ridge is a significant challenge in implant dentistry. To solve this problem, several augmentation techniques, such as guided bone regeneration (GBR), onlay bone grafts, distraction osteogenesis, and ridge splitting techniques, have been proposed and used for several years. Among these methods, vertical ridge augmentation using guided bone regeneration aims to build space and guide osteoblasts to this space to promote osteogenesis. The aim of guided bone regeneration is to maintain and stabilize the space and block the proliferation of adjacent soft tissue. In our hospital, we encountered a case of a woman in her forties with an atrophied mandible, who underwent implant surgery in the right mandible. Titanium reinforced Gore-Tex (TRG) was used to augment the mandible and titanium mesh was used in the left mandible. Favorable results were obtained. This report compares the two methods and reviews the relevant literature.

Study on Dressing Conditions for Creep-feed in Cubic Boron Nitride Grinding of OrthoMTA Compacters (OrthoMTA 컴팩터의 크리프피드 CBN 연삭을 위한 드레싱 조건 연구)

  • Maeng, Heeyoung;Baek, Eun-Pyo
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.23 no.1
    • /
    • pp.69-74
    • /
    • 2014
  • An OrthoMTA compacter is made by machining a Ni-Ti alloy wire using tapered helix creep-feed grinding machines. This aim of this study is to find the optimal dressing conditions to sharpen the corner of a cubic boron nitride (CBN) wheel. On the basis of the results of various experiments, it is verified that the most important factors in dressing are the dressing depth and feeding method, whereas the feed rate has less importance for producing a smaller corner R value. The study also finds the optimum dressing depth to reduce the dressing time, a feeding speed and method to stabilize the machining, and the mesh grade for the CBN wheel to make the groove of the compacter deeper.

Using the mesh electrode for TCO-Iess dye-sensitized solar cells application (메쉬전극을 이용한 TCO-Iess 염료태양전지제작)

  • Jung, Ki-Young;Ju, In-Suk;Sung, Youl-Moon;Kwak, Dong-Joo;Park, Cha-Soo
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
    • /
    • 2009.10a
    • /
    • pp.403-405
    • /
    • 2009
  • 본 연구에서는 염료태양전지의 제작 시 고가의 TCO전극을 사용하지 않고 간단히 광전극을 대체할 수 있는 방법으로 메쉬전극을 이용하는 TCO-less 염료태양전지를 제작하였다. 메쉬전극을 이용한 TCO-less 염료태양전지의 구조는 "Glass / 메쉬전극($TiO_2$를 딥코팅 한 후 염료를 흡착시킴) / 전해질 / 멤브레인 필터 / 상대전극(Pt-coated TCO) / Glass" 로 구성된다. 제작된 샘플의 광전변환 효율은 약 1.5% 였으며 fill factor는 0.55로 나타났다. 향후 계획으로 효율을 향상 시킬 수 있는 방법을 도입하여 광전류밀도와 fill factor를 개선하는 연구를 진행할 예정이다.

  • PDF

A Study of $H_{2}O_{2}$ Production and BPA/17${\beta}$-estradiol Removal by Ultrasound and Pulsed UV in the Presence of Various Catalysts (Ultrasound와 Pulsed UV 조사시 $H_{2}O_{2}$ 발생량과 보조제 주입시 bisphenol A, 17${\beta}$-estradiol의 제거에 대한 연구)

  • Han, Jongh-Hun;Lee, Sung-Jae;Yoon, Yeo-Min;Her, Nam-Guk
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.26 no.2
    • /
    • pp.313-319
    • /
    • 2012
  • This study investigated the relative degradation of commonly known endocrine-disrupting compounds such as bisphenol A (BPA) and 17${\beta}$-estradiol (E2) using ultrasound (US) and pulsed ultraviolet (PUV) in water. The removal efficiency of BPA and E2 was determined as a function of generating power and $H_{2}O_{2}$ production. The ultrasound and PUV irradiation of the aqueous solution was performed in 3 L and 90 L stainless reactor at a constant temperature of $20^{\circ}C$ with an applied power of 200 W and 2000 W, respectively. The removal of BPA and E2 by US and PUV varied with catalysts. The experiments were conducted under the following conditions: total operating time, 30 min; initial concentration, 1 uM. In the case of E2 (10 min), % removal was 92.5/95.8/87.6/82.4, while % removal of BPA (10 min) was 62.3/82.3/91.1/67.0/64.3 in various conditions (PUV, $PUV+H_2O_2$, PUV+wire mesh, $PUV+TiO_2$ coated wire mesh), respectively.

Geochemical Dispersion and Enrichment of Fluvial Sediments Depending on the Particla Size Distribution (입도분포에 따른 하상퇴적물의 지구화학적 분산 및 부화)

  • 이현구
    • Economic and Environmental Geology
    • /
    • v.32 no.3
    • /
    • pp.247-260
    • /
    • 1999
  • Geochermical characteristics of the fluvial sediments deprnding on particle size distribution size were investigated in the respect of majir, minor and rare eath element chemisitry. Ratios of $Al_{2}O_{3}/Na_{2}O$ and $K_{2}O/Na_{2}O$ of the sediments show the homogeneous valus, and partly positive correlation with $SiO_{2}/Al_{2}O_{3}$, respecively. Characteristics of minor element ratios (V/Ni, Cr/V, Ni/Co and Zr/Hf)are within the lower and narrow range. Thesesuggested that sediment sources may be acidic to intermediate granitic rock, and may be explained by simple weathering and sedimentation. With increasing SiO2 contents, concentrations of $Al_{2}O_{3}$, $Fe_{2}O_{3}$, CaO and MgO decreased, but those of $K_{2}O$ and $Na_{2}O$ increased, Concentrations of Ba, Be, Cs, Cu, Li, Ni, Sr, V and Zr show comparatively normal negative and some positive trends. Compared with the mean composition of granite, concentrations of $Al_{2}O_{3}$, $Fe_{2}O_{3}$, MnO, CaO and MgO in the sediments of the study area were highly enriced. Among some minor and rare earth elements, concentrations of As, Cd, Cu, and V were enriched, but those of Be, Ce, Rb, Sc, Sr and Zn were depleted when compared with average composition of granite. By decreasing of particle size fractions, SiO2, Rb and Sr conterts decreased, but concentrations of $Al_{2}O_{3}$, $Fe_{2}O_{3}$, CaO, MgO, $TiO_{2}$, MgO, $P_{2}O_{5}$, Be, Cu, Hf, Pb, V and Zr increased. From the correlations between particle size fractions and element concenreations, some elements of $Fe_{2}O_{3}$, CaO, MgO, $P_{2}O_{5}$, Cu, Ni, Zn and Zr showed typical trends in the secondary contramination sediments. These trends are typically shown under 100 mesh fractions. It indicates that the fraction of minus 100 mesh is the optimum size fraction for geochemical and environmental survey.

  • PDF

Printable Time Temperature Integrator Consisting of Oxygen Indicator and Cover Film with Various Oxygen Permeability (다양한 산소 투과도를 가진 커버필름과 산소지시물질로 제작된 인쇄형 TTI)

  • Kim, Do Hyeon;Jang, Han Dong;Han, Seo Hyeon;Ahn, Myung Hyun;Lee, Seung Ju
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
    • /
    • v.24 no.2
    • /
    • pp.41-48
    • /
    • 2018
  • A printable time temperature integrator (TTI) consisting of oxygen indicator and cover films with various oxygen permeability was developed. The printing ink contained methylene blue (oxygen indicator) which changed in color during storage. $TiO_2$ and glycerol for UV-activation of TTI and zein and ethanol for printing performance were also contained in the printing ink. The cover film on the ink was employed to control the color change rate and temperature dependency (Arrhenius activation energy, $E_a$) by using the different films (PE, PET, OPP, and LLDPE). The film properties were varied by annealing. TTI was produced by silk screen printing. As a result, the color change rates were different for the cover films, being the highest in TTI with LLDPE, followed by OPP, PE, and PET. The rate decreased with increase in the cover film thickness. The $E_a$ was the highest in TTI with LLDPE, followed by OPP, PE, and PET. The $E_a$ did not change with the cover film thickness. The annealed PVC and PET film were lower in oxygen permeability than the unannealed ones, indicating the lower color change rate.

Study on Metal Microfilter Coated with Ceramics by Using Plasma Thermal Spray Method (플라즈마 용사를 이용한 복합세라믹 미세필터 연구)

  • Song, In-Gyu;Lee, Young-Min;Shin, Hyun-Myung;Choi, Hae-Woon
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.35 no.9
    • /
    • pp.1035-1040
    • /
    • 2011
  • This research was performed on a microfilter made of a hybrid material (ceramic + metal) that was coated with ceramics on the metal-filter surface by using the thermal spray method. The ceramic powders used were $Al_2O_3+40TiO_2$ powder with a particle size of $20{\mu}m$ and $Al_2O_3$ (98%+)powder with a particle size of $45{\mu}m$. The metal filters were filter-grade $20{\mu}m$, $30{\mu}m$, and $50{\mu}m$ sintered metal powder filters (SIKA-R 20 IS, 30 IS, 50 IS; Sinter Metals Filters) and filter-grade $75{\mu}m$ sintered mesh filter with five layers. Ceramic-coated filters that were coated using the thermal spray method had a great influence on powder material, particle size, and coating thickness. However, these filters showed a fine performance when used as micro-filters.

Electrode properties upon the substitution of Mo for Mn in Zr-basd AB2-type Hydrogen Storage Alloys (Zr1-xTixV0.4Ni1.2Mn0.4-yMoy계 합금전극의 Mo 함량에 따른 물성 및 전극특성)

  • Seo, Chan-Yeol;Park, Choong-Nyeon
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.11 no.4
    • /
    • pp.189-202
    • /
    • 2000
  • $AB_2$ type Zr-based Laves phases alloys have been studied for potential application as a negative electrode in a Ni-MH battery. The $AB_2$-type electrodes have a much higher energy density than $AB_5$-type electrodes per weight, however they have some disadvantages such as poor activation behavior and cycle life etc. Nonetheless, the $AB_2$-type electrodes have been studied very extensively due to their high energy density. In this study, in order to develop the cycle life, the Mn of $AB_2$ alloy composition was substituted partially by Mo. The alloys were melted by arc furnace and remelted 4-5 times for homogeneity. The alloy powder was used below 200-325 mesh for experiments. The structures and phases of the alloys were analyzed by XRD, SEM and EDS, and measured the curve of a pressure-composition isotherms. The electrodes were prepared by cold pressing of the copper-coated(25 wt%) alloy powders, and tested by a half cell. The results are summarized as follows. The cycle life was improved with the increase of Mo amount in $Zr_{1-x}Ti_xV_{0.4}Ni_{1.2}Mn_{0.4}Mo_y$(x=0.3, 0.4) and the activation was faster, whereas the discharge capacity decreased.

  • PDF

Fabrication and Characterization of piezoelectric thick films prepared by Screen Printing Method (Screen Printing법을 이용한 압전 후막의 제조 및 특성연구)

  • 김상종;최형욱;백동수;최지원;윤석진;김현재
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2000.07a
    • /
    • pp.873-876
    • /
    • 2000
  • Characteristics of piezoelectric thick films prepared by screen printing method were investigated. The piezoelectric thick films were printed using Pb(Mg,Nb)O$_3$-Pb(Zr,Ti)O$_3$system. The lower electrodes were coated with various thickness of Ag-Pd by screen printing to investigate the effect as a diffusion barrier and deposited with Pt by sputtering on Ag-Pd. The ceramic paste was prepared by mixing powder and binder with various ratios using three roll miller. The fabricated thick films were burned out at 650$^{\circ}C$ and sintered at 950$^{\circ}C$ in the O$_2$condition for each 20, 60min after printing with 350mesh screen. The thickness of piezoelectric thick film was 15∼20 $\mu\textrm{m}$ and the Ag-Pd electrode acted as a diffusion barrier above 3 $\mu\textrm{m}$ thickness. When the lower electrode Ag-Pd was 6 $\mu\textrm{m}$ and the piezoelectric thick films were sintered by 2nd step (650$^{\circ}C$/20min and 950$^{\circ}C$/1h) using paste mixed Pb(Mg,Nb)O$_3$-Pb(Zr,Ti)O$_3$$.$ MnO$_2$+ Bi$_2$O$_3$. V$_2$O$\_$5/ and binder in the ratio of 70:30, the remnant polarization of thick film was 9.1 ${\mu}$C /cm$^2$.

  • PDF

Effect of Grinding Method and Grinding Rate on the Dry Beneficiation of Kaolin Mineral (분쇄방식 및 분쇄율이 고령토 광물의 건식 정제에 미치는 영향)

  • Kim, Sang-Bae;Choi, Young-Yoon;Cho, Sung-Baek;Kim, Wan-Tae
    • Journal of the Mineralogical Society of Korea
    • /
    • v.21 no.2
    • /
    • pp.129-138
    • /
    • 2008
  • The characteristics of beneficiating kaolin mineral by liberation (selective grinding) and air classification have been investigated, comparing the grinding rates of ball mill and impact mill. The ore was ground using a ball mill and a impact mill to evaluate the grindability of the two grinding methods based on the constant production amount of fine particles in size less than 325 mesh. Then, the fine product was further separated into two fractions using an air-classifier and each fraction was chemically analyzed to compare the beneficiation efficiency of the two grinding methods. The chemical grade of kaolin mineral decreased as increasing the grinding rate of both the mills. particularly in the case of ball mill because of overgrinding impurities such as quartz and feldspar. In the case of the ball milling, the fine fraction less than 325 mesh was air-classified at a cutting point of $43\;{\mu}m$. The production rate of the air-classified concentrate was found to be 66.2 wt%, removing 5.3% of $Fe_2O_3$ and 34.6% of CaO. Under the same conditions mentioned above with the impact mill, the production rate of the air-classified concentrate was 64.4 wt%, removing 34.2% of $Fe_2O_3$, 67.6% of CaO and 25.0% of $TiO_2$. Therefore, our results indicate that impact mill is superior to ball mill in terms of impurity removal.