• Title/Summary/Keyword: Oxide

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Separation of Ferrous Materials from Municipal Solid waste Incineration Bottom Ash (생활폐기물(生活廢棄物) 소각(燒却) 바닥재의 자력선별(磁力選別)에 따른 ferrous material의 분리(分離) 특성(特性))

  • Um, Nam-Il;Han, Gi-Chun;You, Kwang-Suk;Cho, Hee-Chan;Ahn, Ji-Whan
    • Resources Recycling
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    • v.16 no.3 s.77
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    • pp.19-26
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    • 2007
  • The bottom ash of municipal solid waste incineration generated during incineration of municipal solid waste in metropolitan area consists of ceramics, glasses, ferrous materials, combustible materials and food waste and so on. Although the ferrous material was separated by the magnetic separation before the incineration process, of which content accounts for about $3{\sim}11%$ in bottom ash. The formation of a $Fe_3O_4-Fe_2O_3$ double layer(similar to pure Fe) on the iron surface was found during air-annealing in the incinerator at $1000^{\circ}C$. A strong thermal shock, such as that takes place during water-cooling of bottom ash, leads to the breakdown of this oxidation layer, facilitating the degradation of ferrous metals and the formation of corrosion products and it existed as $Fe_2O_3,\;Fe_3O_4\;and\;FeS_2$. So, many problems could occur in the use of bottom ash as an aggregate substitutes in construction field. Therefore, in this study, the separation of ferrous materials from municipal solid waste incineration bottom ash was investigated. In the result, the ferrous product(such as $Fe_2O_3,\;Fe_3O_4,\;FeS_2$ and iron) by magnetic separator at 3800 gauss per total bottom ash(w/w.%) accounted for about 18.7%, and 87.7% of the ferrous product was in the size over 1.18 mm. Also the iron per total bottom ash accounted for about 3.8% and the majority of it was in the size over 1.18 mm.

THE BOND CHARACTERISTICS OF PORCELAIN FUSED BY TITANIUM SURFACE MODIFICATION (타이타늄의 표면개질에 따른 도재 결합 특성)

  • Choi, Taek-Huw;Park, Sang-Won;Vang, Mong-Sook;Yang, Hong-So;Park, Ha-Ok;Lim, Hyun-Pil;Oh, Gye-Jeong;Kim, Hyun-Seung;Lee, Kwang-Min;Lee, Kyung-Ku
    • The Journal of Korean Academy of Prosthodontics
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    • v.45 no.2
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    • pp.169-181
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    • 2007
  • Statement of problem: Titanium is well known as a proper metal for the dental restorations, because it has an excellent biocompatibility, resistance to corrosion, and mechanical property. However, adhesion between titanium and dental porcelains is related to the diffusion of oxygen to the reaction layers formed on cast-titanium surfaces during porcelain firing and those oxidized layers make the adhesion difficult to be formed. Many studies using mechanical, chemical and physical methods to enhance the titanium-ceramic adhesion have been actively performed. Purpose: This study meant to comparatively analyse the adhesion characteristics depending on different titanium surface coatings after coating the casts and wrought titanium surfaces with Au and TiN. Material and method: In this study, the titanium specimens (CP-Ti, Grade 2, Kobe still Co. Japan) were categorized into cast and wrought titanium. The wrought titanium was cast by using the MgO-based investment(Selevest CB, Selec). The cast and wrought titanium were treated with Au coating($ParaOne^{(R)}$., Gold Ion Sputter, Model PS-1200) and TiN coating(ATEC system, Korea) and the ultra low fusing dental porcelain was fused and fired onto the samples. Biaxial flection test was done on the fired samples and the porcelain was separated. The adhesion characteristics of porcelain and titanium after firing and the specimen surfaces before and after the porcelain fracture test were observed with SEM. The atomic percent of Si on all sample surfaces was comparatively analysed by EDS. In addition, the constituents of specimen surface layers after the porcelain fracture and the formed compound were evaluated by X-ray diffraction diagnosis. Result: The results of this study were obtained as follows : 1. The surface characteristics of cast and wrought titanium after surface treatment(Au, TiN, $Al_2O_3$ sandblasting) were similar and each cast and wrought titanium showed similar bonding characteristics. 2. Before and after the biaxial flection test, the highest atomic weight change of Si component was found in $Al_2O_3$ sandblasted wrought titanium(28.6at.% $\rightarrow$ 8.3at.%). On the other hand, the least change was seen in Au-Pd-In alloy(24.5at.% $\rightarrow$ 9.1at.%). 3. Much amount of Si components was uniformly distributed in Au and TiN coated titanium, but less amount of Si's was unevenly dispersed on Al2O3 sandblasting surfaces. 4. In X-ray diffraction diagnosis after porcelain debonding, we could see $Au_2Ti$ compound and TiN coating layers on Au and TiN coated surfaces and $TiO_2$, typical oxide of titanium, on all titanium surfaces. 5. Debonding of porcelain on cast and wrought titanium surface after the biaxial flection is considered as a result of adhesion deterioration between coating layers and titanium surfaces. We found that there are both adhesive failure and cohesive failure at the same time. Conclusion: These results showed that the titanium-ceramic adhesion could be improved by coating cast and wrought titanium surfaces with Au and TiN when making porcelain fused to metal crowns. In order to use porcelain fused to titanium clinically, it is considered that coating technique to enhance the bonding strength between coating kKlayers and titanium surfaces should be developed first.

TEMPERATURE CHANGE IN THE PULP ACCORDING TO POLISHING CONDITION OF VARIOUS RESTORATIVE MATERIALS (여러가지 수복물의 polishing조건에 따른 치수 온도변화)

  • Baik, Byeong-Ju;Park, Jong-Ha;Yang, Jeong-Suk;Lee, Seung-Young;Kim, Jae-Gon
    • Journal of the korean academy of Pediatric Dentistry
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    • v.26 no.2
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    • pp.365-376
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    • 1999
  • The importance of finishing and polishing the restoration has been described by several authors. The final step provides for improved metallurgical properties, better marginal adaptation, reduced plaque accumulation. Unfortunately, finishing of the restorations can produce damage from temperature rises at the pulpal wall. The aim of this study was to determine the changes in temperature can be occurred during the use of finishing and polishing instruments under a variety of conditions. ; with or without a water coolant, intermittent or continuous operation, high or low rotation speed, remaining dentin thickness and various restorative materials. Class V preparations were cut on extracted molars and restored with composite resin(Z 100), resin-modified glass ionomer cements(Dyract, Fuji II LC), and amalgam. Finishing was done with aluminum oxide coated disc($Sof-lex^{(R)}$ polishing disc, 3M, USA). The following results were obtained. 1. The rise of temperature during polishing of amalgam restorations was the highest among the all experimental groups except polishing with water coolant(P<0.05). However, there were no statistical differences in temperature rises between Z 100, Dyract and Fuji II LC(P>0.05). 2. The intrapulpal temperature was greatly influenced by the applied time, and intermittent polishing was showed significantly lower temperature rises than continuous polishing(P<0.01). 3. The intrapulpal temperature was increased according to the application of polishing regard less of using water coolant. However, polishing with water coolant showed significantly lower temperature in the pulp than not used water coolant(P<0.01).

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Synthesis of anhydrite in the mixtures of alunite and limestone by roasting (Alunite와 limestone의 혼합소성에서의 무수석고의 합성)

  • Kim, Hyung-Seok;Ahn, Ji-Whan;Kim, Hwan;Shin, Kang-Ho;Cho, Dong-Sung
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.11 no.5
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    • pp.190-196
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    • 2001
  • Alunite was dehydrated at 500~$580^{\circ}C$ and desulfurued at 580~$780^{\circ}C$ in air atmosphere. Therefore, this study was carried out to investigate the formation conditions of anhydrite ($CaCO_4$) when the mixtures of alunite TEX>$[K_2SO_4$.$Al_2(SO_4)_3$.$4Al(OH)_3$] and limestone ($CaCO_3$)were roasted. Alunite scarcely dected the partial pressures of $CO_2$(g), but limestone was bansformed into CaO at $650^{\circ}C$ in air and $900^{\circ}C$ in saturated $CO_2$(g), atmosphere, respectively. When the the mixtures of 1 mol of alunite and 6 rnol of limestone were roasted for 2 hours at lO00C in air and saturated $CO_2$(g), anhydrite was formed at $550^{\circ}C$ calciumlangbeinite, at $700^{\circ}C$and haiiyne, at 800~$950^{\circ}C$. The formation rate of anhydrite in air and saturated $CO_2$(g), was 99.0 % and 95.0 %, respectively. then the formation rate of anhydrite was not changed in air atmosphere but increased according to the decreasing of the particle size of limestone in saturated $CO_2$(g). Therefore, when the mixture of 1 mol of alunite and 6 rnol of limestone were roasted, the clinker composed of lmol of haiiync and 1 mol of calciumlangbeiilte can be manufactured

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Anti-Atopic Effects of Mixed Extracts from Date Plum, Persimmon, and Mulberry Leaves (고욤잎, 감잎 및 뽕잎 복합추출물의 항아토피 효과)

  • Cho, Byoung Ok;Yin, Hong Hua;Shin, Jae Young;Fang, Chong Zhou;Chang, Che Denis;Jang, Seon Il
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.4
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    • pp.501-509
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    • 2016
  • The present study investigated the anti-atopic effects of mixed extracts from date plum, persimmon, and mulberry leaves (DPME) on atopic dermatitis (AD)-like skin lesions in hairless mice. The in vivo results demonstrated that DPME treatment significantly reduced the dermatitis clinical score and epidermal thickness in AD-like skin lesions. Histological analyses showed that DPME treatment strongly inhibited dermal infiltration of inflammatory cells and activity of mast cells in AD-like skin lesions. DPME treatment inhibited production of serum IgE and interluekin (IL)-4 in hairless mice with AD. Moreover, DPME treatment significantly suppressed production of tumor necrosis factor $(TNF)-{\alpha}$ and IL-6 cytokines in phorbol 12-myristate 13-acetate plus calcium ionophore A23187-stimulated HMC-1 human mast cells. In addition, DPME treatment reduced production of pro-inflammatory mediators (nitric oxide, prostaglandin E2, $TNF-{\alpha}$, and IL-6) in lipopolysaccharide-stimulated RAW 264.7 macrophages. Therefore, the results of this study indicate that the anti-atopic and anti-inflammatory effects of DPME may be involved in the regulation of inflammatory responses, suggesting that DPME may be used as an anti-atopic dermatitis material and natural anti-inflammatory ingredient.

Antimutagenic and Antitumor Effects of Codonopsis lanceolata Extracts (더덕 추출물의 항돌연변이 및 항종양 효과)

  • Kim, Soo-Hyun;Choi, Hyun-Jin;Chung, Mi-Ja;Cui, Cheng-Bi;Ham, Seung-Shi
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.10
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    • pp.1295-1301
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    • 2009
  • This study was carried out to investigate the mutagenic, antimutagenic, cytotoxicity and antitumor effect of Codonopsis lanceolata (CL). CL was extracted with 70% ethanol and then further fractionated to hexane, chloroform, ethyl acetate, butanol and water. Antimutagenic, cytotoxicity and antitumor effects of CL extracts were measured by using Ames test, SRB method, and the tumor growth inhibition test. CL extracts did not show any mutagenicity in the Ames test; however, 70% ethanol extracts and its fractions had strong antimutagenic effects against mutation induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and 4-nitroquinoline-1-oxide (4NQO). The ethyl acetate fraction of CL (200 ${\mu}g$/plate) showed approximately 72.1% inhibitory effect on the mutagenesis induced by 4NQO against TA98 strain, whereas 69.6% and 67.0% inhibitions were observed on the mutagenesis induced by MNNG and 4NQO against TA100 strain. In anticancer effects, the cytotoxicity of CL extract and its fractions against cancer cell lines including human cervical adenocarcinoma (HeLa), human hepatocellular carcinoma (HepG2), human breast adenocarcinoma (MCF-7), human lung carcinoma (A549) and transformed primary human embryo kidney (293) were investigated. The treatment of 1 mg/mL CL ethyl acetate fraction had the highest cytotoxicity of 74.5%, 70.7% and 80.3% against HeLa, MCF-7 and A549 cells, respectively. In contrast, the extract and its fractions showed only 2$\sim$31% cytotoxicity for a normal human kidney cell line (293). In vivo anticancer effect of CL extract was tested using Balb/c mice transplanted sarcoma-180 cells. CL ethyl acetate fraction showed the highest inhibition rate of 56.4% at the 50 mg/kg concentration.

Pharmacological Activities of Coffee Roasted from Fermented Green Coffee Beans with Fungal Mycelia in Solid-state Culture (진균류 균사체의 고체발효 커피생두로부터 조제한 원두커피의 생리활성)

  • Shin, Ji-Young;Kim, Hoon;Kim, Dong-Gu;Baek, Gil-Hun;Jeong, Heon-Sang;Yu, Kwang-Won
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.3
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    • pp.487-496
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    • 2013
  • Green coffee beans (CB, Indonesian Mandheling) were fermented with three kinds of mushrooms (Phellinus linteus, PL; Hericium erinaceum, HE; Ganoderma lucidum, GL) or two kinds of mycelia from molds (Monascus purpureus, MP; Monascus ruber, MR) using solid-state culture to enhance physiological activity. After the roasting of fermented green coffee beans, roasted coffees were extracted with a hot-water decoction or 95% ethanol reflux. Yields from hot water extracts (HW, 17.7~25.3%) were higher than those from ethanolic extracts (EE, 9.5~12.2%). Hot-water extracts of roasted coffees from green coffee beans fermented with two molds (MP-CB-HW and MR-CB-HW) showed higher total polyphenols, flavonoids, and DPPH free radical scavenging activity than roasted coffees from non-fermented (CB-HW) or fermented green coffee beans with the three mycelia from mushrooms. MR-CB-HW also had the most potent macrophage stimulating and mitogenic activity (1.32 and 1.40-fold of CB-HW, respectively). In addition, MP-CB-EE and MR-CB-EE did not show any cytotoxicity to the RAW 264.7 cell at a concentration of $100{\mu}g/mL$, and these extracts significantly inhibited nitric oxide (NO) production from the LPS-stimulated RAW 264.7 cell line (38.6 and 37.0% of the LPS-treated group). Meanwhile, the chlorogenic acid concentrations of MP-CB-HW or MR-CB-HW highly increased (to 76.21 or $76.73{\mu}g/mL$, respectively), but caffeine concentrations were not affected by solid-state fermentation. In conclusion, the physiological activities of roasted coffees were enhanced by the solid-state culture of green coffee beans with M. purpureus or M. ruber, suggesting that these roasted coffees could possibly serve industrial applications as functional coffee beverages.

Qualities and Anti-inflammatory Activity of Kyungokgos Sold in Local Markets (국내 시판 경옥고 제품의 품질 특성 및 항염증 활성)

  • Lee, Ka-Soon;Kim, Gwan-Hou;Kim, Hyun-Ho;Seong, Bong-Jae;Kim, Sun-Ick;Han, Seung-Ho;Kang, Eun Ju;Yoo, Yung Choon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.3
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    • pp.335-341
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    • 2013
  • Kyungokgos purchased in local markets in Korea vary in their combination and mixing ratios during processing. This study was investigated qualities of Kyungokgos manufactured traditionally to evaluating its qualities. The general components of Kyungokgos were moisture (18.62~49.78%), ash (0.198~1.211%), protein (0.89~3.58%), lipid (0.16~1.14%) and carbohydrates (47.95~77.08%). The color values of L, a, and b were 26.49~73.87, 16.51~38.64, and 45.41~88.94, respectively. The viscosity was classified into three non-Newtonian type groups: high, medium, and non-dilatant, according to the increase of loop execution times. Three extracts (KOG-1, -7, and -8, in a 30-fold dilution) showed no cytotoxicity toward RAW 264.7 cells, while the extracts of KOG-2, -4, and -5 showed a low cytotoxic effect. KOG-1 and -2 extracts with low cytotoxicity markedly inhibited the production of the inflammatory mediators-nitric oxide (NO) and tumor necrosis factor-alpha (TNF-${\alpha}$) in LPS-stimulated RAW 264.7 cells. These results indicate that KOG-1 and -2 extracts have anti-inflammatory activity in LPS-stimulated RAW 264.7 macrophages.

Fractionation and Availability of Heavy Metals in Paddy Soils near Abandoned Mining Areas (광산인근 논토양의 중금속 분획화 및 유효도)

  • Jung, Goo-Bok;Kim, Won-Il;Ryu, In-Soo
    • Korean Journal of Environmental Agriculture
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    • v.19 no.4
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    • pp.319-323
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    • 2000
  • This study was conducted to compare fractionations and availability of heavy metal in paddy soils near five abandoned mining areas. The sequential extraction procedure was used to fractionate the heavy metals in soils into the designated from water $soluble(H_2O)$, $exchangeable(0.5M\;KNO_3)$, organically bound(0.5M NaOH), $oxide/carbonate(0.05M\;Na_2-EDTA)$, and $sulfide/residual(4M\;HNO_3)$. EDTA and $HNO_3$ extractable of Cd, Pb, and Zn, and NaOH and $HNO_3$, extractable of Cu were predominant chemical forms. The ratio of $H_2O+KNO_3$ extractable of Cd, Zn, Cu, and Pb were 25.1, 8.7, 4.0, and 0.4%, respectively. The ratio of $H_2O+KNO_3$ extractable heavy metal were negatively correlated with soil pH, while $EDTA+HNO_3$ extractable heavy metal were positively correlated. The most consistent distribution patterns were found when the soil samples were grouped according to their total contents. Specially, the ratio of $H_2O+KNO_3$ extractable heavy metal were higher as total contents of heavy metal were increased. The ratio of $H_2O+KNO_3$ extractable heavy metal(Cd 1.06, Cu 0.15, Pb 0.01, and Zn 0.05%) were lower at the high soil pH than those(Cd 31.31, Cu 4.06, Pb 1.75, and Zn 10.16%) at the low level. Compared to other chemical forms, the degree of contribution for $KNO_3$ extractable form to the Cd uptake to brown rice was high, whereas that for EDTA and $HNO_3$ extractable forms were high to the Zn.

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Inhibition of Inflammation by Popillia flavosellata Ethanol Extract in LPSinduced RAW264.7 Macrophages (LPS로 염증 유도된 RAW 264.7세포에 대한 참콩풍뎅이(Popillia flavosellata) 에탄올 추출물의 항염증 효과)

  • Yoon, Young-Il;Hwang, Jae-Sam;Kim, Mi-Ae;Ahn, Mi Young;Lee, Young-Bo;Han, Myung Sae;Goo, Tae-Won;Yun, Eun-Young
    • Journal of Life Science
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    • v.25 no.9
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    • pp.993-999
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    • 2015
  • The beetle Popillia flavosellata has been no reported its functional effects. In this study, we investigated the anti-inflammatory effect of P. flavosellata ethanol extract (PFE) on RAW 264.7 mouse macrophage cells treated with lipopolysaccharide (LPS) for the induction of inflammation. First, we examined the cytotoxicity of PFE in the RAW 264.7 cells at a concentration of 2,000 μg/ml or less. To evaluate the anti-inflammatory effects of PFE, we investigated the expression levels of proinflammatory cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-6, and proinflammatory enzymes, such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-induced RAW 264.7 cells. In addition, we examined whether PFE inhibited the translocation of nuclear factor kappa B (NF-κB) p65 into the nucleus in the LPS-induced RAW 264.7 cells. We found that the protein levels of TNF-α and IL-6 were decreased in the LPS-induced RAW 264.7 cells after the treatment with PFE in a dose-dependent manner. In addition, we confirmed that PFE inhibited the translocation of NF-κB p65 into the nucleus, as well as the protein expression levels of iNOS and COX-2. Accordingly, we propose that PFE exerts an anti-inflammatory effect through the down-regulation of NF-κB p65, TNF-α, IL-6, iNOS, and COX-2 via the toll like receptor (TLR)-4 inflammatory signaling pathway.