• Title/Summary/Keyword: oxidized

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A comparative clinical study on oxidized titanium implants and sandblasted large-grit acid etched implants in soft bone

  • Lee, Jun-Young;Song, Ji-Eun;Jung, Ui-Won;Kim, Chang-Sung;Choi, Seong-Ho;Cho, Kyoo-Sung
    • Journal of Periodontal and Implant Science
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    • v.39 no.sup2
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    • pp.205-212
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    • 2009
  • Purpose: The aim of this retrospective study was to compare the survival rate of oxidized titanium implants and sandblasted large-grit acid etched implants in soft bone. Methods: 201 oxidized titanium implants were inserted in 84 patients between May 1999 and May 2004. 120 sandblasted large-grit acid etched implants were inserted in 74 patients between December 2000 and May 2004. The patients were followed-up 0${\sim}$5 years in ITI group or 0${\sim}$6 years in BRA group, respectively. The following information was collected from the patient records: age, gender, systemic disease, implant type, number, length and diameter of the implants, their location in the jaws, bone quantity, the number of failed implants, the causes of failure, and advanced surgery for bone augmentation. Results: In the oxidized titanium implants, 8 implants showed early failure, and 1 implant showed late failure, respectively. The cumulative survival rate was 95.48%. In the sandblasted large-grit acid etched implants, 1 implant showed late failure and cumulative survival rate was 99.10%. The cumulative survival rate and the survival rates in the case of the advanced procedure during the implant placement were not significantly different in both groups. Conclusions: Oxidized titanium implants and sandblasted large-grit acid etched implants can be used successfully in soft bone regardless of the surgical methods used during the implant placement. (J Korean Acad Periodontol 2009;39:205-212)

C-V Characteristics of Oxidized Porous Silicon (다공성 실리콘 산화막의 C-V 특성)

  • Kim, Seok;Choi, Doo-Jin
    • Journal of the Korean Ceramic Society
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    • v.33 no.5
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    • pp.572-582
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    • 1996
  • The porous silicon was prepared in the condition of 70mA/cm2 and 5.10 sec and then oxidized at 800~110$0^{\circ}C$ MOS(Metal Oxide Semiconductor) structure was prepared by Al electrode deposition and analyzed by C-V (Capacitance-Voltage) characteristics. Dielectric constant of oxidized porous silicon was large in the case of low temperature (800, 90$0^{\circ}C$) and short time(20-30min) oxidation and was nearly the same as thermal SiO2 3.9 in the case of high temperature (110$0^{\circ}C$) and long time (above 60 min) It is though to be caused byunoxidized silicon in oxidized porous silicon film and capacitance increase due to surface area increment effect.

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Antioxidant Activity of Daidzin and Puerarin toward Oxidation of Human Low Density Lipoprotein (갈근에서 분리한 Daidzin 및 Puerarin의 사람 Low Density Lipoprotein 대한 항산화 효과)

  • 박종옥;김경순;지영애;류병호
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.1
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    • pp.25-31
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    • 1997
  • Antioxidative activity of daidzin and puerarin isolated from Puerariae radix against oxidation of low density lipoprotein(LDL) was investigated. The concentration of daidzin at 100$\mu\textrm{g}$/$m\ell$ and puerarin at 60$\mu\textrm{g}$/$m\ell$ inhibited Cu$^{2+}$-mediated oxidation of LDL almost completely. The electrophoretic mobility of oxidized LDL by addition of daidzin(100$\mu\textrm{g}$/$m\ell$) and puerarin(60$\mu\textrm{g}$/$m\ell$) was faster than that of native LDL, but slower than that of oxidized LDL. The oxidized LDL induced by J774 or macrophage was inhibited strongly in the presence of 100$\mu\textrm{g}$/$m\ell$ daidzin and 60$\mu\textrm{g}$/$m\ell$ Puerarin. The formation of conjugated dienes in the oxidized LDL was strongly inhibited by 100$\mu\textrm{g}$/$m\ell$ daidzin and 60$\mu\textrm{g}$/$m\ell$ puerarin.n.

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Effect of Electrochemical Redox Reaction on Biochemical Ammonium Oxidation and Chemical Nitrite Oxidation

  • Jeon, Bo-Young;Seo, Ha-Na;Kang, Seung-Won;Park, Doo-Hyun
    • Journal of Microbiology and Biotechnology
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    • v.20 no.3
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    • pp.485-493
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    • 2010
  • A modified graphite felt electrode with neutral red (NR-electrode) was shown to catalyze the chemical oxidation of nitrite to nitrate under aerobic conditions. The electrochemically oxidized NR-electrode (EO-NR-electrode) and reduced NR-electrode (ER-NR-electrode) catalyzed the oxidation of $1,094{\pm}39$ mg/l and $382{\pm}45$ mg/l of nitrite, respectively, for 24 h. The electrically uncharged NR-electrode (EU-NR-electrode) catalyzed the oxidation of $345{\pm}47$ mg/l of nitrite for 24 h. The aerobic bacterial community immobilized in the EO-NR-electrode did not oxidize ammonium to nitrite; however, the aerobic bacterial community immobilized in the ER-NR-electrode bioelectrochemically oxidized $1,412{\pm}39$ mg/l of ammonium for 48 h. Meanwhile, the aerobic bacterial community immobilized on the EU-NR-electrode biochemically oxidized $449{\pm}22$ mg/l of ammonium for 48 h. In the continuous culture system, the aerobic bacterial community immobilized on the ER-NR-electrode bioelectrochemically oxidized a minimal $1,337{\pm}38$ mg/l to a maximal $1,480{\pm}38$ mg/l of ammonium to nitrate, and the community immobilized on the EU-NR-electrode biochemically oxidized a minimal $327{\pm}23$ mg/l to a maximal $412{\pm}26$ mg/l of ammonium to nitrate every two days. The bacterial communities cultivated in the ER-NR-electrode and EU-NR-electrode in the continuous culture system were analyzed by TGGE on the $20^{th}$ and $50^{th}$ days of incubation. Some ammonium-oxidizing bacteria were enriched on the ER-NR-electrode, but not on the EU-NR-electrode.

Reproducible Resistance Switching and Physical Characteristics of TiOx films with Oxidation Temperature and Time

  • Kim, Jong-Gi;Na, Hee-Do;Sohn, Hyun-Chul
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.08a
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    • pp.171-171
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    • 2010
  • In this work, we investigated the effect of the oxidation temperature on the unipolar and bipolar resistance switching behaviors of the oxidized TiO-x films. TiOx films on Pt electrodes were fabricated by the oxidation of Ti films at $550^{\circ}C$ for 1 to 3 hours. The unipolar and bipolar resistance switching properties were investigated with the oxidation temperature and time. Also, the crystal structure and the physical properties such as chemical bonding states of TiOx layers were characterized in addition to the resistance switching characteristics. The resistance switching behaviors of TiOx films oxidized at above $450^{\circ}C$ and below $650^{\circ}C$ was shown. So, we investigated that the resistance switching behaviors of TiOx films oxidized at $550^{\circ}C$ with the oxidation time from 1 to 3 hour. The memory windows of unipolar switching in the oxidized TiOx films were reduced with increasing the oxidation time, but those of the bipolar switching were slightly enlarged. The enlargement of rutile TiO2 peak with increasing the oxidation time and temperature was studied by X-ray diffraction. An increase of non-lattice oxygen and Ti3+ in the TiOx films with the oxidation times was investigated by X-ray photoemission spectroscopy. It was expected that the uipolar and bipolar resistive switching of the oxidized TiOx film was strongly related with the migration of non-lattice oxygen anions and schottky barrier height, respectively.

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Fabrication and Characteristics of MMIC Substrate using Oxidation of Porous Silicon (다공질 실리콘 산화법을 이용한 MMIC 기판의 제조 및 그 특성)

  • Kwon, O.J.;Kim, K.J.;Lee, J.S.;Lee, J.H.;Choi, H.C.;Lee, J.H.;Kim, K.W.
    • Journal of Sensor Science and Technology
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    • v.8 no.2
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    • pp.202-209
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    • 1999
  • Microstrip line was fabricated on the oxidized porous silicon layer which has nearly electrically and chemically identical properties with thermally oxidized silicon layer. Thick oxidized porous silicon layer of few tenth of micrometers was prepared by thermal oxidation of porous silicon layer on silicon substrate. Multi-step thermal oxidation process was used to obtain high Quality and thick oxidized silicon layer and to release thermal stress. Microstrip line was fabricated on the oxidized porous silicon layer. Its microwave characteristics were measured and the availability for MMIC substrate was investigated.

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The Molecular Weight Distribution Pattern in Oxidized Corn Starch (산화에 따른 옥수수 전분의 분자량 분포 양상)

  • 한진숙;안승요
    • Korean journal of food and cookery science
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    • v.18 no.2
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    • pp.200-205
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    • 2002
  • Corn starch was modified by the oxidation with sodium hypochlorite(NaOCl) and the changes in the distribution of molecular weight were examined. Corn starch was oxidized with 0.25, 0.5, 0.75, 1.0, and 1.5% active Cl/g of starch at pH 7.0 and 25$^{\circ}C$ for 10 min. Oxidation of corn starch caused a change in the molecular weight distribution of amylopectin. The fraction of highest molecular weight in native starch decreased gradually and the fraction of lower molecular weight increased with increasing oxidation. Also, λ$\sub$max/ and iodine binding capacities of oxidized starches decreased and the soluble carbohydrate content increased by oxidation. The differential scanning calorimetric results of oxidized starches showed that the temperature and enthalpies of gelatinization were not changed by oxidation; however, the more the starch was oxidized, the greater the extent of retrogradation.

THE EFFECTS OF RESORBABLE MEMBRANE IN CONJUNCTION WITH OSSEOUS GRAFTS ON THE PERIODONTAL HEALING IN DOGS (흡수성차단막과 골이식재가 성견 치주질환 치조골재생에 미치는 영향)

  • Kim, Chong-Kwan
    • Journal of Periodontal and Implant Science
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    • v.24 no.1
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    • pp.51-63
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    • 1994
  • There has been many attempts to develop a method that can regenerate periodontal tissues that were lost due to periodontal diseasd, but none of them was completely successful. This study was designed to investigate the healing and regeneration of periodontal tissue when bone substitutes such as porous replamineform hydroxyapatite and porous resorbable calcium carbonate were used in combination with oxidized cellulose membrane and collagen absorbable hemostat, compared to a control where only oxidized cellulose membrane or collagen absorbable hemostat were used. Chronic periodontitis was induced on mandibular premolars of and adult dog by placing orthodontic elastic ligatures for 10 weeks. After flap operation, the control group were received oxidized cellulose membrane (control- I )or collagen absorbable hemostat (control- II) only, while one experimental group was given either porous replamineform hydroxyapatite or porous resorbable calcium carbonate in addition to oxidized cellulose membrane (Experimental I-A, I-B), and another experimental group was treated by using either porous replamineform hydroxyapatite or porous resorbable calcium carbonate in addition to collagen absorbable hemostat. (Experimental II-A, II-B) After 56 weeks, healing was histologically analyzed with the following results. 1. Apical migration of junctional epithelium was observed only in areas coronal to the notch for both control and experimental group. 2. Inflammatory cell infiltration was not observed in any groups. 3. Oxidized cellulose membrane and collagen absorbable hemostat were completely resorbed. 4. Newly-formed cementum was observed up to the level where junctional epithelium was located, for both control and experimental groups. 5. Bone formation was limited of the middle portion of the notch in the control group, where as experimental groups showed bone formation up to the level of implant materials coronal to the notch. 6. Minute resorption of apically located portions of implanted materials was observed in experimental group I-B and II-B only.

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Effect of loading time on the survival rate of anodic oxidized implants: prospective multicenter study

  • Kim, Seok-Gyu;Yun, Pil-Young;Park, Hyun-Sik;Shim, June-Sung;Hwang, Jung-Won;Kim, Young-Kyun
    • The Journal of Advanced Prosthodontics
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    • v.4 no.1
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    • pp.18-23
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    • 2012
  • PURPOSE. The purpose of this prospective study was to evaluate the effect of early loading on survival rate or clinical parameter of anodic oxidized implants during the 12- month postloading period. MATERIALS AND METHODS. Total 69 implants were placed in 42 patients. Anodic oxidized implants (GS II, Osstem Cor., Busan, Korea) placed on the posterior mandibles were divided into two groups, according to their prosthetic loading times: test group (2 to 6 weeks), and control group (3 to 4 months). The implant survival rates were determined during oneyear postloading period and analyzed by Kaplan-Meier method. The radiographic peri-implant bone loss and periodontal parameters were also evaluated and statistically analyzed by unpaired t-test. RESULTS. Total 69 implants were placed in 42 patients. The cumulative postloading implant survival rates were 88.89% in test group, compared to 100% in control group (P<.05). Periimplant marginal bone loss (T: $0.27{\pm}0.54$ mm, C: $0.40{\pm}0.55$ mm) and periodontal parameters showed no significant difference between the groups (P>.05). CONCLUSION. Within the limitation of the present study, implant survival was affected by early loading on the anodic oxidized implants placed on posterior mandibles during one-year follow-up. Early implant loading did not influence peri-implant marginal bone loss, and periodontal parameters.

The Study of the Anti-oxidative Effects of Polygonati Multiflori Caulis on Oxidized Brain and Liver Cells in Rats (야교등(夜交藤)이 흰쥐 뇌와 간에서의 산화 억제에 미치는 영향)

  • Lee, Han-Goo;Han, Hyo-Sang;Lee, Young-Jong
    • The Korea Journal of Herbology
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    • v.25 no.1
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    • pp.13-21
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    • 2010
  • Objectives : This study was purposed to the anti-oxidative effects of Polygonati Multiflori Caulis(henceforth PMC) on oxidized brain and liver cells in rats. Methods : After extraction of PMC with water, the water extract was divided into five fractions : hexane, ethyl ether, ethyl acetate, butanol and an aqueous fraction. The phenol contents of each fraction were measured. The lipid peroxidation inhibition effect were then investigated. Results : After processing PCM water and PCM fractionations on oxidized brain cells in rats, the SOD (super oxide dismutase) activity and glutathione content were increased, and the NO (nitric oxide) content was decreased. It had much higher SOD activity than liver cells in rats excluded in the n-BuOH and aqueous fractions. In case of oxidized liver cells in rats, the SOD activity and glutathione content increased, while both the NO content and the MDA (malondialdehyde) content decreased. It had much higher glutathione content than brain cells in rats in the every fractions. It had much lower MDA content than brain cells in rats in the Aqueous fractions and brain cells in rats had much lower MDA content than liver cells in rats in the total extract, n-hexane, EtOEt, EtOAc and n-BuOH fractions. Conclusions : PMC has anti-oxidative effect on oxidized liver cells and brain cells in rats, through there are differences in fraction. Additionally, Anti-oxidative effect of brain cells can be relaxed the mental nerve and it is related PMC effect.