• Title/Summary/Keyword: Well resistance

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Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2009 (설비공학 분야의 최근 연구 동향 : 2009년 학회지 논문에 대한 종합적 고찰)

  • Han, Hwa-Taik;Lee, Dae-Young;Kim, Seo Young;Choi, Jong-Min;Baik, Yong-Kyu;Kwon, Young-Chul
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.22 no.7
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    • pp.492-507
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    • 2010
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2009. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of general thermal and fluid flow, fluid machinery and piping, and new and renewable energy. Various topics were covered in the field of general thermal and fluid flow such as an expander, a capillary tube, the flow of micro-channel water blocks, the friction and anti-wear characteristics of nano oils with mixtures of refrigerant oils, etc. Research issues mainly focused on the design of micro-pumps and fans, the heat resistance reliability of axial smoke exhaust fans, and hood systems in the field of fluid machinery and piping. Studies on ground water sources were executed concerning two well type geothermal heat pumps and multi-heat pumps in the field of new and renewable energy. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included the heat transfer in thermoelectric cooling systems, refrigerants, evaporators, dryers, desiccant rotors. In the area of industrial heat exchangers, researches on high temperature ceramic heat exchangers, plate heat exchangers, frosting on fins of heat exchangers were performed. (3) In the field of refrigeration, papers were presented on alternative refrigerants, system improvements, and the utilization of various energy sources. Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and $CO_2$ were studied. Efforts to improve the performance of refrigeration systems were made applying various ideas of suction line heat exchangers, subcooling bypass lines and gas injection systems. Studies on heat pump systems using unutilized energy sources such as river water, underground water, and waste heat were also reported. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. In the area of cogeneration systems, papers on energy and economic analysis, LCC analysis and cost estimating were reported. Studies on ventilation and heat recovery systems introduced the effect on fire and smoke control, and energy reduction. Papers on district cooling and heating systems dealt with design capacity evaluation, application plan and field application. Also, the maintenance and management of building service equipments were presented for HVAC systems. (5) In the field of architectural environment, various studies were carried to improve indoor air quality and to analyze the heat load characteristics of buildings by energy simulation. These studies helped to understand the physics related to building load characteristics and to improve the quality of architectural environment where human beings reside in.

Analysis Corrosion Products Formed on the Great Buddha Image of Kotokuin Temple in Kamakura (고덕원 국보 동조아미타여래좌상의 표면에 생성한 부식생성물의 해석)

  • Matsuda Shiro;Aoki Shigeo;Kang, Dai-il
    • 보존과학연구
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    • s.17
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    • pp.161-182
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    • 1996
  • In natural atmosphere, copper and copper alloy have been used to make buddha statues and ornaments of historic buildings since the abovementioned metals have corrosion resistance in some extent, and the patinaformed on the surface of the metals has provided the people aesthetic satisfaction with its beauty. But in atmosphere polluted by $SO_x$and $NO_x$, the patina layer does not work as a protective film, and it allows damages of the metal. Since 1992, Tokyo National Research Institute of Cultural Properties(TNRICP)has conducted studies on the influence of atmospheric pollution on metal cultural property held under open air. The Great Buddha Image which is located in Kamakura about 50km west from Tokyo, has been selected as one of the objects to study because it is made by copper alloy and it has stood exposed in the air for about a few hundreds years. Furthermore it is also the reason to study on it that there are many cultural properties in the surroundings of it. We have analysed the components and the structure of the corrosion products formed on the surface of the Buddha, have carried out exposure tests using the alloy samples which have simulated the components of the Great Image, and have observed climated and polluted air in order to discuss the relation between corrosion of metals in open air and conditions of the atmosphere. In this paper, the authors have described the components and the structure of the corrosion product formed on the surface of the Great Image by means of X-ray fluorescence spectroscopy and X-ray diffraction. The conclusions are as follows. (1) Sulfate patina composed mainly with brochantite were detected on the all sides of the Image and the amount of the patina is found more on the back of the Image facing to north. (2) Antlerite were detected on the back and a park of the left side facing to west, and formation of it was considered to have close relation with malignant atmosphere. (3) A big amount of chloride patina which mainly composed of atacamite were observed on the front facing to south. (4) Carbonate patina mainly composed of malachite were detected on the area where brochantite was often detected as well. It suggested that malachite had been transformed into brochantite by deteriorated atmosphere. (5) On the all sides of the Image, patina were observed together with copper oxides mainly composed of cuprous oxide. It showed that the surface layer of the Image consists of two layers : inner layer of oxide and outer layer of patina. (6) Corrosion products of lead which was a component of copperalloy were detected on the all sides : the main lead product found on the front was chlorophosphate whereas the one on the back was sulfate.

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A study of pain perception related to IV therapy in hospitalized preschool children and their mothers (정맥주사와 채혈시 학령전기 아동과 어머니가 인지하는 동통)

  • 임지영
    • Journal of Korean Academy of Nursing
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    • v.22 no.1
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    • pp.49-67
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    • 1992
  • Most hospitalized children will experience physical pain as well as psychological distress. Preschool children's pain perception related to painful procedures can increase due to elevated anxiety and fear because they do not have understanding logical of their disease and hospitalization. In particular, they are distressed about needle - related procedures which are feared because they are seen to be a cause of bodily damage. This descriptive study attempted to identify pain perception levels in preschool children and their mothers. A self-reporting measurement and behavioral observation were used to collect the data. A total of 25 hospitalized preschool children and their mothers were investigated and data were collected about 60 painful procedures. Data collection was carried out by the researcher and two trained investigators from November first to December tenth. Three insruments were used to collect the data : Faces Pain Rating Scale(FPRS) developed by Beyer was used to measure the degree of preschool children's pain perception about painful procedures. The Visual Analogue Scale(VAS) devised by Huskisson was used to assess the degree of mothers' pain perception about their children's painful procedures. A Pain Behavioral Checklist based on the Procedure Behavior Check List by LeBaron and Zelter and modified by the researcher was used to observe behaviors of preschool children, their mothers, and nurses when the painful procedures took place. The data were analyzed by an SPSS program, and were tested using real numbers, percentages, Pearson correlation coefficient, t-test, and ANOVA. The results of this study are as follows : 1. Of all the painful procedures, the mean score for the FPRS for the preschool children's pain perception was 4.02 points, and the mean score for the VAS of mothers' pain perception was 10.92 points. 2. A Positive correlation which was statistically significant was found between the pain perception of preschool children and their mothers (r=.53, p<.01). that is, the higher the children's pain perception was, the higher their mothers' pain perception was. 3. The characteristics of the painful procedures related with children's pain perception as follows : The type of painful procedure was found to be statistically significant (F=23.44, p<.01), Among the three procedures Ⅳ starting was found to be perceived as the most painful procedures to the children. The greater the number of times that the procedure had been done, the higher the pain perception was (F=4.44, p<.01), and the longer the duration of the procedure, the higher the pain perception wa(r=.30, p<.05). Pain perception in the treatment room was higher than in the children's room(t=6.30, <.01), pain perception in the mother's presence was the higher than when the mother was not present (t=2.91, p<.01). 4. The characteristics of the painful procedures related with the mothers' pain perception as follows : The type of painful procedure was found to be statistically significant(F=6.01, p<.01). Among the three procedures Ⅳ sampling was found to be perceived as the most painful procedures to the mothers. The greater the number of times that the procedure had been done, the higher the pain perception was (F=5.95, p<.01), and the longer the duration of the procedure, the higher the pain perception was (r=.31, p<.05). Pain perception in the treatment room was higher than in the children's room (t=3.51, p<.01), but pain perception in the mother's presence showed statistically significant no difference. 5. Of all of the 19 children's behaviors during the painful procedures, the most frequent behaviors observed Were as follows in order of frequency “crying”, “screamirig”, “facial grimacing”, “physical resistance”, Of all of the nine methers' behaviors, the most frequent by observed in “console children”, “hold children”, “applaud children”, Of all of the 11 nurses' behaviors during the painful procedures, the mast frequent in order were “smiling”, “physical restraint”, “console children”, “praise children”. 6. A positive correlation between children's and mothers' pain perception and children's behaviors was found to be statistically significant (r=.65, p<.01, r=67, p<.01). Also the relationship between children's and mothers' pain percertion, and mothers' behavior was found to be statistically significant (r=.57, p<. 01, 4=.60, p<.01). The relationship between children's pain perception and nurses' behaviors was also found to be statistically significant (r=.46, p<.01), but there was difference between mothers' pain perception and nurses' behaviors.

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The Immunohistochemical Analysis for the Expression of Survivin, an Inhibitor of Apoptosis Protein, in Non-small Cell Lung Cancer (비소세포폐암에서 아포프토시스 억제 단백질 Survivin 발현에 관한 면역조직학적 분석)

  • Ko, Mi-Hye;Myoung, Na-Hye;Lee, Jae-Whan;Cho, Eun-Mi;Park, Jae-Seuk;Kim, Keun-Youl;Lee, Kye-Young
    • Tuberculosis and Respiratory Diseases
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    • v.48 no.6
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    • pp.909-921
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    • 2000
  • Background : Defects in apoptotic signaling pathways play important role in tumor initiation, progression, metastasis and resistance to treatment. Several proteins which may promote tumorigenesis by inhibiting apoptosis were identified. The survivin protein is the member of inhibitor of apoptosis protein(IAPs) family which inhibits apoptosis. Unlike other IAPs, it is expressed in during the fetal period but not in adult differentiated tissues. Many reports have stated that survivin is selectively expressed in many cancer cell lines and cancer tissues. We performed immunohistochemical analysis for survivin expression in non-mall cell lung cancer to get evaluate its clinical implication. Methods : Twenty nine surgically resected lung cancers were examined. Immunohistochemical staining were performed by immuno-peroxidase technique using avidin-biotinylated horseradish pemxidase complex in the formalin-fixed, paraffin-embedded tissue $4{\mu}m$ section. Anti-survivin polyclonal antibody was used for primary antibody and anti-p53 monoclonal antibody was also used to analyze the correlation between survivin and p53 expression. The survivin expression scores were determined by as the sum of the stained area and intensity. Results : Immunohistochemical analysis showed cancer specific expression of survivin in 20 of 29 cases (69.0%). Western blot analysis also showed the selective survivin expression in tumor tissue. There was no correlation between survivin expression and clinicopathological parameters and prognosis. We analyzed the ∞π'elation between survivin expression and p53 expression, but found none. Conclusion: We confirmed the tumor specific expression of survival in non-small cell lung canær. But this expression was not correlated with clinical parameters as well as histology, tumor stage, recurrence, and survival rate. Also it was not statistically correlated with the expression of p53.

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A Research on Ball-Balancing Robot (볼 벨런싱 로봇에 관한 연구)

  • Kim, Ji-Tae;Kim, Dae-young;Lee, Won-Joon;Jin, Tae-Seok
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.05a
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    • pp.463-466
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    • 2017
  • The purpose of this paper is to develop a module capable of all-directional driving different from conventional wheeled robots, and to solve the problems of the conventional mobile robot with side driving performance degradation, It is possible to overcome the disadvantages such as an increase in the time required for the unnecessary driving. The all - direction spherical wheel drive module for driving a ball - balancing robot is required to develop a power transfer mechanism and a driving algorithm for driving the robot in all directions using three rotor casters. 3DoF (Axis) A driver with built-in forward motion algorithm is embedded in the module and a driving motor module with 3DoF (axis) for driving direction and speed is installed. The movement mechanism depends on the sum of the rotation vectors of the respective driving wheels. It is possible to create various movement directions depending on the rotation and the vector sum of two or three drive wheels. It is possible to move in different directions according to the rotation vector field of each driving wheel. When a more innovative all-round spherical wheel drive module for forward movement is developed, it can be used in the driving part of the mobile robot to improve the performance of the robot more technically, and through the forward-direction robot platform with the drive module Conventional wheeled robots can overcome the disadvantage that the continuous straightening performance is lowered due to resistance to various environments. Therefore, it is necessary to use a full-direction driving function as well as a cleaning robot and a mobile robot applicable in the Americas and Europe It will be an essential technology for guide robots, boarding robots, mobile means, etc., and will contribute to the expansion of the intelligent service robot market and future automobile market.

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Conjugal transfer and fate of the genetically engineered $Km^{r}$ gene in freshwater environments (유전자 조작기법으로 변형시킨 $Km^{r}$ 유전자의 담수 환경에서의 전이 및 행방)

  • 김치경;이성기
    • Korean Journal of Microbiology
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    • v.28 no.3
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    • pp.219-228
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    • 1990
  • A kanamycin resistance($Km^r$) gene was studied for its transfer in natural freshwater environments by using the natural bacterial isolate(M1) of DK1 and the DKC601 strain, $Km^r$ plasmid of which was genetically engineered from the NI strain. The transfer frequency ofthe $Km^r$ gene and rearrangement of the $Km^r$ plasmid were compared between the gnetically engineered microorganism(GEM) and the NI parental strain by conjugation with the same recipient strain. The transfer frequency of the $Km^r$ gene was about $9.1\times 10^{-12}-1.8\times 10^{-11}$ in both the GEM and NI strains at 5 to $10^{\circ}C$, but the frequency of the NI was about 10 times higher than that of the GEM at 20 to $30^{\circ}C$. The $Km^r$ plasmid in the transconjugants obtained by conjugation of the NI with the MY1 strain as a ricipient showed alot of rearrangement, but the $Km^r$ plasmid transferred from the GEM was stable without alteration of its size. When the MT2 strain was used as a recipient, however, such a rearrangement of the $Km^r$ plamid was observed in the transconjugants obtained from the GEM as well as the NI strain. In those transconjugants obtained from different mating pairs and water environments, the plasmid were appeared to decrease in their number as the period of conjugation time was prolonged, but only the $Km^r$ plasmid transferred from the GEM kept having its size of 52kb. Therefore, the $Km^r$ gene was transferred at the same rate from the GEM and NI strains in natural freshwater environment, but the gene of the GEM strain was more stable than the NIduring conjugation and the $Km^r$ plasmid was rearranged by changing the recipient strain for conjugation in any water environments.

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A Study on Commemoration Characteristics of Vietnam War Memorials in the United States of America (미국에 있는 베트남전쟁 메모리얼에 나타난 기념성)

  • Lee, Sang-Seok
    • Journal of the Korean Institute of Landscape Architecture
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    • v.43 no.1
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    • pp.1-15
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    • 2015
  • The purpose of this study was to analyze the commemoration characteristics of Vietnam War Memorials(VWM) in the United States(VWMUS). Through site survey and internet research, the researcher selected 87 VWMUS except monuments simply with markers, and analyzed 5 analysis items: design concepts, spatial characteristics, landscape details, sculptures, and interpretive texts and symbols. The results are as follows: 1. The analysis revealed that the main concepts of VWMUS were to cherish victims of the Vietnam War(85 sites (97.7%)), show veteran's dedication for country(85 sites(97.7%)), and publicize the contribution of groups by troop, regional, and membership(84 sites(96.6%)). 2. Most VWMUS were located in memorial parks and plazas. 59 memorials(67.8%) were designed to pursue the completion of each memorial assuming the form of symmetry and circles. On the other hand, 12 memorials(13.8%) were typed memorial walls and 11 memorials(12.6%) were formed by spatial sequence including various landscape details and grading. 3. Stone walls were mainly used to cherish victims of the War at 65 memorials(74.7%), and also, Flags like the Stars and Stripes, POW MIA flags, and state flags were hoisted to symbolize memorial's identity at all memorials. Additionally, Benches, monuments, markers, posts and columns, ponds and channels, Helicopters were partially introduced some memorials. 4. Sculptures were used 21 memorials(24.1%) which were smaller in numbers than other War Memorial in the U.S.A., for black stonewall were used for the main element of VWMUS. Except for a few sculptures that aimed to represent the Vietnam War symbolically and narratively, 16 memorials(18.4%) were formed to realistically express the image of wounded soldiers and their hardship in the Vietnam War. 5. KIA, MIA, Veteran's name were written and their images depicted on walls, Also, the symbolic phrase, 'ALL GAVE SOME, SOME GAVE ALL' and 'DUTY, HONOR, COUNTRY' were written on the memorials walls, and the POW MIA symbols were printed on the flags and engraved on walls. 6. In the United States of America, Democratic patriotism was considered a main ideological value in VWMUS by engraving KIA MIA's names on the walls, hoisting flags Stars and Stripes and POW MIA, and writing symbolic phrases 'ALL GAVE SOME, SOME GAVE ALL' and 'DUTY, HONOR, COUNTRY'. On the contrary, in Vietnam, nationalism, patriotism, and socialism were emphasized as main ideologies through raising war victory and resistance to foreign power as well as writing the symbolic phrase 'TO-QUOC-GUI-CONG' meaning 'our country remember your achievement' on memorial towers. Further study will be required to comparatively analyze VWM in order to understand national characteristics in Korea, Australia, U.S.A, and Vietnam.

Properties of Hot Weather Nuclear Power Plant Concrete with Water Cooling Method and Retarding used (배합수 냉각방법 및 지연제 사용에 따른 서중 원전콘크리트의 특성)

  • Lee, Seung-Han;Jung, Yong-Wook;Jang, Seok-Soo;Yeo, In-Dong;Choi, Jong-Oh
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.9
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    • pp.4602-4609
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    • 2013
  • In summer and winter, the difference between the temperature during the day and that during the night is high, which leads to various problems during concrete placement, such as cracks and defects in the concrete as well as low durability and strength. Although nuclear power plant concrete is widely used for placement in all seasons, particular attention must be paid to its quality during the summer. Therefore, we evaluated the effects of a cooling method for mixing water, which is a commonly used hot weather precooling method, and the use of a retarder, on the characteristics of Nuclear Power Plant concrete. In the cooling method for mixing water, cold water at 5 was used, with 50% of the water content consisting of ice flakes. The effects of using a retarder were evaluated by reviewing the characteristics of the cement at the unset stage and after hardening. To evaluate the characteristics of the unset cement, we measured the slump, air volumes, setting times, and pressure strengths after hardening. Furthermore, we measured the heat of hydration at different temperatures; the loss of heat was minimized using insulation. Both the slump time and the complete ageing time of the air volume were found to be 120 min at $20^{\circ}C$ and 40 min at $40^{\circ}C$. In the case when the cooling method for mixing water was used and in the case when a retarder was used, the initial and final sets by penetration resistance were delayed, and the delay decreased with increasing air temperature. For the heat of hydration, the cooling method for mixing water not only lowered the maximum temperature but also delayed its attainment. However, the use of a retarder had no effect on the maximum temperature. Moreover, in the early ages (e.g., 3 and 7 days), the pressure strength of the concrete was lower than that of plain cement. However, the strength of 28-day concrete met the standard construction specifications.

Assessment of Growth Conditions and Maintenance of Law-Protected Trees in Je-cheon City (제천시 보호수의 생육환경 및 관리현황 평가)

  • Yoon, Young-Han;Ju, Jin-Hee
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.28 no.2
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    • pp.67-74
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    • 2010
  • Law-protected trees are our precious asset as natural resources with history and tradition and natural heritage which should be protected and maintained well to bequeath next generation. Law-protected trees have not only thremmatologic and genetic meaning but also environmental and emotional meaning for their value to be high. This study investigated location, vitality, wrapping condition of root area and status of maintenance of the trees to figure out their growth environment and status of maintenance in a small-middle city through survey on those of law-protected trees in Je-cheon. There showed 300 more year old trees in Je-cheon mostly and the number of trees located in flat fields was the highest. For location type, village, hill and road types were presented in the order and for degree of development, land for building was found most frequently. The average electric resistance of the formative layer was measured to be $8.4k{\Omega}$ and four trees showed bark separation. Most law-protected trees underwent tree surgery, and complete bareness of root area was observed in a tree. The root area of two trees was covered with concrete. pH of soil was recorded to be 5.0~8.4 with its average of 7.1 and electric conductivity(EC) was less than 0.5 dS/m. For status of maintenance rearing facilities were placed for 16 trees out of totally 48 ones and stone fence was done for three ones. Tree surgery was conducted for 33 trees to prevent and to treat decomposed parts of holes. Direction boards were installed for 23 trees. Based on these results, measures to manage systematically law-protected trees in Jecheon could be suggested as follows. First, a sufficient space for growth of low part of trees should be secured. Second, a voluntary management should be induced by advertising them to residents in a community. Third, rearing facilities and direction boards of law-protected trees should be placed and related education should be conducted. Fourth, through operation of the department for law-protected trees consisting of related professions and cooperation among related departments the trees should be maintained continuously.

Effects of conditions for anodization and cyclic precalcification treatments on surface characteristics and bioactivity (양극산화와 석회화 순환처리 조건이 타이타늄 박판의 표면특성 및 생체활성에 미치는 영향)

  • Jang, Yong-Seok;Lee, Kang-Gyu;Jeon, Woo-Yong;Han, A-Lum;Lim, Chung-Ha;Lee, Min-Ho;Bae, Tae-Sung
    • Korean Journal of Dental Materials
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    • v.45 no.4
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    • pp.243-256
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    • 2018
  • The purpose of this study was to investigate the effects of the anodization and cyclic calcification treatment on the surface characteristic and bioactivity of the titanium thin sheet in order to obtain basic data for the production of bioactive titanium membrane. A $30{\times}20{\times}0.08mm$ titanium sheets were prepared, and then they were pickled for 10 seconds in the solution which was mixed with $HNO_3:HF:H_2O$ in a ratio of 12: 7: 81. The $TiO_2$ nanotube layer was formed to increase the specific surface area of the titanium, and then the cyclic calcification treatment was performed to induce precipitation of hydroxiapatite by improvement of the bioactivity. The corrosion resistance test, wettability test and immersion test in simulated body solution were conducted to investigate the effect of these surface treatments. The nanotubes formed by the anodization treatment have a dense structure in which small diameter tubes are formed between relatively large diameter tubes, and their inside was hollow and the outer walls were coupled to each other. The hydroxyapatite precipitates were well combined on the nanotubes by the penetration into the nanotube layer by successive cyclic calcification treatment, and the precipitation of hydroxyapatite tended to increase proportionally after immersion in simulated body solution as the number of cycles increased. In conclusion, it was confirmed that induction of precipitation of hydroxyapatite by cyclic calcification treatment after forming the nanotube $TiO_2$ nanotube layer on the surface of the titanium membrane can contribute to improvement of bioactivity.