• Title/Summary/Keyword: $OH^-$

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Adsorption of Water on Cation Supported Layer Silicates (陽이온이 支持된 Layer Silicate 上에서의 水分의 吸着)

  • Jong Taik Kim;Shon, Jong Rack
    • Journal of the Korean Chemical Society
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    • v.19 no.5
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    • pp.317-324
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    • 1975
  • The adsorptions of gaseous $H_2O\;and\;D_2O\;on\;Na^+-,\;Ca^{2+}-,\;and\;Al^{3+}$ montmorillonites at various temperatures were undertaken. Break down of ir hydroxyl stretching bands into four Gaussian components was made by means of manual technique. Resonance theory of water to form silanol hydroxyl group was supported by $3625cm^{-1}$ band for OH and $2680cm^{-1}$ band for OD which depend on amounts of water adsorbed. The broad bands at about $3400 cm^{-1}\;and\;2475cm^{-1}$ were assigned to stretching band of silanol OH hydrogen bonded to adsorbed water. The prominent $3230 cm^{-1}$ band together with component around $2345 cm^{-1}$ were attributed to adsorbed $H_2O\;and\;D_2O$ respectively. The chemical nature of the hydrogen bonding between adsorbed water and neighboring surface OH was explained adequately in terms of electrostatic interaction.

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Comparison of OH radical generation depending on anatase to rutile ratio of TiO2 nanotube Photocatalyst (Anatase와 Rutile 결정상 비율에 따른 TiO2 nanotube의 OH radical 생성량 비교 연구)

  • Lee, Hyojoo;Lee, Yongho;Pak, Daewon
    • Journal of Korean Society on Water Environment
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    • v.35 no.6
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    • pp.550-556
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    • 2019
  • This study was carried out to improve the photocatalytic reaction of TiO2 photocatalyst. During the photocatalytic reaction, OH radicals are generated and they have an excellent oxidation capability for wastewater treatment. To evaluate the OH radicals generated according to crystallographic structure of TiO2 nanotubes photocatalyst, a probe compound, 4-Chlorobenzoic acid was monitored to evaluate OH radical. Ultraviolet light was applied for photocatalytic reaction of TiO2. The 4-Chlorobenzoic acid solution was prepared at laboratory. TiO2 nanotube was grown on titanium plate by using anodization method. The annealing temperature for TiO2 nanotube was varied from 400 to 900 ℃ and the crystal forms of the TiO2 nanotube was analyzed. Depending on annealing temperature, TiO2 nanotubes have shown different crystal forms; 100% anatase (0 % rutile), 18.4 % rutile (81.6 % anatase), 36.6 % rutile (63.4 % anatase) and 98.6% rutile (1.4% anatase). As the annealing temperature increases, the rutile ratio increases. OH radical generation from 18.4 % rutile TiO2 nanotube plate was about 3.8 times higher than before annealing and 1.4 times higher than only 100 % anatase-TiO2 nanotube. The efficiency of the 18.4% rutile TiO2 nanotube was the best in comparison to TiO2 nanotube with 18.4 %, 36.6 % and 98.6 % rutile. As a result, photocatalytic ability of 18.4 % rutile-TiO2 nanotube plate was higher than 100 % anatase-TiO2 nanotube plate.

Detection of Iron Phases Presents in Archaeological Artifacts by Raman Spectroscopy

  • Barbosa, A.L.;Jimenez, C.;Mosquera, J.A.
    • Corrosion Science and Technology
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    • v.17 no.2
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    • pp.60-67
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    • 2018
  • The compounds associated with corrosion, in metallic archaeological samples of carbon steel of insular origin were evaluated to establish their degree of deterioration and structural damage against air pollution. The iron phases present in samples of archaeological artifacts were detected by Raman spectroscopy and confocal Raman microcopy. These samples mainly exhibited ing mainly ${\beta}$-FeO(OH) type goethite oxyhydroxides and small amounts of akaganeite ${\alpha}$-FeO(OH) lepidocrocite ${\gamma}$-FeO(OH) due to dominant chloride in a marine environment and non-stoichiometric oxyhydroxides Fe (II + / III +) as indicators of early corrosion. Some parts showed the presence of magnetic maghemite indicating high corrosion. ${\gamma}$-FeO(OH) is a precursor of phases associated with advanced marine corrosion. By studying its decomposition by Raman spectroscopy, it was synthesized with the following sequence: ${\gamma}-FeO(OH){\rightarrow}{\alpha}-FeO(OH)+{\gamma}-FeO(OH)$, ${\rightarrow}{\gamma}-Fe_2O_3+Fe_3O_4$. Ferric compounds provided evidence for the effect of intensity of laser on them, constituting a very useful input for the characterization of oxidation of iron in this type of artifacts. Thus, destructive analysis techniques should be avoided in addition to the use of small amounts of specimen.

Photocatalytic Oxidation of NOx onCaO/TiO2 (CaO/TiO2에서 NOx의 광촉매 산화반응에 대한 연구)

  • Shin Joong-Hyeok;Lim Woong-Mook;Jun Jin
    • Journal of Environmental Science International
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    • v.15 no.6
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    • pp.533-538
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    • 2006
  • Removal of $NO_x$ on $CaO/TiO_2$ photocatalyst manufactured by the addition of $Ca(OH)_2$ was measured in relation with the amount of $Ca(OH)_2$ and calcination temperature. In case of pure $TiO_2$, the $NO_x$ removal decreased greatly with the increase of calcination temperature from $500^{\circ}C\;to\;700^{\circ}C$, whereas in the photocatalyst added with $Ca(OH)_2$, the removed amount of $NO_x$ was high and constant regardless of calcination temperature. Considering $NO_x$ removal patterns depending on the amount of $Ca(OH)_2$ added(50, 30, 10wt%), high removal rate showed at the photocatalysts containing less than 30wt% of $Ca(OH)_2$, and it was about 30% higher than that of pure $TiO_2$. From the XRD patterns, it is seen that the addition of $Ca(OH)_2$ contributes to maintaining the anatase structure that is favourable to photocatalysis. It also indicates that the possibility of the formation of calcium titanate($CaTiO_3$) by reacting with $TiO_2$ above $700^{\circ}C$. Apart from the favourable crystalline structure, the addition of $Ca(OH)_2$ helped increase the alkalinity of photocatalyst surface, thus promoting the photooxidation reaction of $NO_x$.

A study of association between Cold Hypersensitivity and Orthostatic Hypotension(OH) (냉증과 기립성 저혈압의 연관성에 관한 연구)

  • Jang, Gyeong-Ho;Song, Hwa-Suk;Lee, Dong-Gyu;Kim, Se-Hyeon;Kim, Sang-U
    • Journal of Oriental Medical Thermology
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    • v.2 no.1
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    • pp.29-34
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    • 2003
  • Purpose The purpose of this study was to verify the association between Cold Hypersensitivity and Orthostatic Hypotension(OH). Method This study was carried out on 39 women who visited outpatient department of Dept. of Gynecology. Bundang CHA oriental Hospital. College of Medicine. Pochun CHA univ. from December 2001 to November 2002. We divided them into two groups (Orthostatic Hypotension Group 24, Normal BP Group 15) and investigated general characteristics, weight, height, past history. family history through out the patient's note. OH was assessed 1 minute after the patients rose from a supine position by using tilting table. For the diagnosis of cold hypersensitivity, thermographic measurements were performed on two pairs of areas(palm-upper arm and back of hand-upper arm. And for that of the feet, other two pairs of areas(anterior thigh-top of the feet and posterior thigh-heel). And then by which verify the association between Cold Hypersensitivity and Orthostatic Hypotension(OH) Results As a results, 16 out of 24 patients, the OH group had cold hypersensitivity and 4 out of 15 Patients the normal BP group had cold hypersensitivity. It means that there was association between Cold Hypersensitivity and Orthostatic Hypotension(OH). Conclusion Above these results, we can reach the conclusion that OH is considered one of the causes of cold hypersensitivity.

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The Effect of Hepatitis Treatment-Tang No.1 on Ethanol-Induced Cytotoxicity of Hep G2 Cells (Hep G2 세포에서 간염제1탕의 에탄올에 의한 세포독성 억제효과)

  • Park, Young-Kweon;Kim, Gang-San;Kang, Byung-Ki;Ra, Ki-Ung
    • The Journal of Internal Korean Medicine
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    • v.22 no.1
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    • pp.79-85
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    • 2001
  • Object : Hepatitis Treatment-tang No.1 has been used for the treatment of Liver disease and Jaundice. Long-term EtOH exposure leads to immunoregulatory and detoxification impairment. This study aimed to determine the relationship between TNF-${\alpha}$ production and expression, and EtOH-induced cytotoxicity on Hep G2 cells. Method : Cells were incubated with EtOH in the presence or absence of HT. The cells were tested after 24 hours and, again, after 48 hours. Cytoviability and TNF-${\alpha}$ release were analyzed by MTT assay and enzyme linked immunosorbent assay (ELISA), respectively. After 24 hours of EtOH exposure, the cytoviability decreased, and the release of TNF-${\alpha}$ was increased. Increased amounts of TNF-${\alpha}$ contribute to EtOH-induced cytotoxicity. The Anti-TNF-${\alpha}$ antibody almost abolished it. Interestingly, EtOH-induced cytotoxicity and TNF-${\alpha}$ production were inhibited by HT. Moreover, when HT was used in combination with the anti-TNF-${\alpha}$ antibody, there was a marked inhibition of EtOH-induced cytotoxicity. Results : These results suggest that HT may prevent the cytotoxicity through partial inhibition of the TNF-${\alpha}$ secretion.

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The Effect of Artemisia Capillaris Herba on Ethanol-Induced Cytokines(TNF-${\alpha},IL-1{\alpha}$) Secretion in Hep G2 Cells (인진호가 Hep G2 세포에서 에탄올 매개성 Cytokine 분비에 미치는 영향)

  • Sim, Jung-Sub;Kim, Il-Hwan;Kim, Gang-San;Kagn, Byung-Ki;Choi, Su-Deock
    • The Journal of Internal Korean Medicine
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    • v.22 no.1
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    • pp.87-93
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    • 2001
  • A human hepatoma cell line, Hep G2 cells, is reliable for the study of alcohol-induced hepatotoxicity. The aim of this study is to determine the relationship between TNF-${\alpha}$, IL-$1{\alpha}$ production and EtOH-induced cytotoxicity on Hep G2 cells. The cells were incubated with EtOH in the presence of Artemisia Capillaris Herba(AC) for 24 hours and in the absence of AC for 48 hours. Cytoviability and cytokines release were analyzed by MTT assay and enzyme linked immunosorbent assay (ELISA), respectively. After 24 hours of EtOH exposure, the cytoviability had markedly decreased, and the release of cytokines had increased. The increased amount of cytokines contributed to EtOH-induced cytotoxicity. Anti-TNF-${\alpha}$ and IL-$1{\alpha}$ antibodies almost abolished it. Interestingly, EtOH-induced cytotoxicity and cytokines production were inhibited by AC. Moreover, when AC was used in combination with antibodies, there was a marked inhibition of EtOH-induced cytotoxicity. These results suggest that EtOH-induced cytotoxicity may regulate, by various factors, and AC may prevent the cytotoxicity through partial inhibition of the $TNF-{\alpha}$ and IL-$1{\alpha}$ secretion.

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Association between serum 25-hydroxyvitamin D levels and adiposity measurements in the general Korean population

  • Kim, Dasom;Kim, Jihye
    • Nutrition Research and Practice
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    • v.10 no.2
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    • pp.206-211
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    • 2016
  • BACKGROUND/OBJECTIVES: Obesity, which is a known risk factor for many chronic diseases, has also been associated with vitamin D deficiency. This study explored the relationship between serum 25-hydroxy-vitamin D [25(OH)D] concentrations and adiposity measures in a general Korean population using the most recent, nationally representative survey data. SUBJECTS/METHODS: The study sample consisted of 4,771 Korean adults (${\geq}19years$) who participated in the fifth Korean National Health and Nutrition Examination Surveys. Serum 25(OH)D was determined by radioimmunoassay. Body mass index (BMI), waist circumference (WC) and total body fat content were measured as adiposity measurements. Total body fat content was measured by dual-energy X-ray absorptiometry. RESULTS: The serum 25(OH)D level was significantly higher in men than in women. Serum 25(OH)D concentration was positively correlated with energy intake, and it was negatively correlated with total body fat content (P < 0.0001) and percentage body fat (P < 0.0001) after adjustment for age in both sexes, while was inversely correlated with BMI only in women. In multivariable regression analysis, serum 25(OH)D was inversely associated with the total body fat content after adjustment for age, BMI, education, region, smoking, alcohol consumption, physical activity, and energy intake only in men (P = 0.0047). However, the serum 25(OH)D concentration was not associated with WC or BMI, indicators of adiposity after adjustment for potential risk factors. CONCLUSIONS: Serum 25(OH)D concentration was independently associated with the total body fat content in a general Korean population, but it may be not associated with the indicators for estimating adiposity, such as WC or BMI.

A Case of Vitamin D-Dependent Rickets, Type 1 (제 1형 비타민 D 의존성 구루병 1례)

  • Hur, Ji Hye;Lee, Chong Guk;Sur, Chung Wook
    • Clinical and Experimental Pediatrics
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    • v.48 no.6
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    • pp.665-668
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    • 2005
  • "Rickets" is the term applied to impaired mineralization at epiphyseal growth plate, resulting in deformity and impaired linear growth of long bones. Rickets may arise as a result of vitamin D deficiency or abnormality in metabolism. Vitamin D-dependent rickets(VDDR) is rare autosomal recessive disorder in which affected individuals have clinical features of vitamin D deficiency. In 1961, Prader first described this disorder including severe clinical features of rickets, such as hypophosphatemia, hypocalcemia, muscle weakness and seizure. Two distinctive hereditary defects, type I VDDR and type II VDDR have been recognized in vitamin D metabolism. Type I VDDR may be due to congenital defects of renal 1 ${\alpha}$-hydroxylase, the enzyme responsible for conversion of $25(OH)D_3$. These patients have low to detectable $1,25(OH)_2D_3$ in presence of normal to raised $25(OH)D_3$. In type II VDDR, renal production of $1,25(OH)_2D_3$ is intact but $1,25(OH)_2D_3$ is not used effectively and target organ resistant to $1,25(OH)_2D_3$ is respectively derived from the abnormality in the vitamin D receptor. We report a case of a 25 month-old girl with typical clinical features of VDDR type I rickets, hypocalcemia, increased alkaline phosphatase and secondary hyperparathyroidism.

Recovery of Phosphorus in Animal Wastewater by Struvite Forming (Struvite 형성에 의한 축산폐수의 인 회수기술 개발)

  • Oh, I.H.;Lee, J.H.;Choi, B.H.;Myung, N.S.;Burns, R.T.
    • Journal of Biosystems Engineering
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    • v.31 no.1 s.114
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    • pp.46-51
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    • 2006
  • This study was carried out to recover phosphorus in animal wastewater using a magnesium source. $MgCl_2$, as a magnesium source, was shown a SP (soluble phosphorus) recovery rate of 98% in both the aeration and the NaOH tests to adjust pH around 8.5. In case of MgO, the recovery rate of SP were 88% with the aeration and 58% with the NaOH. In case of ammonia nitrogen recovery, $MgCl_2$ was shown the recovery rate of 17% with aeration and 18% with NaOH. MgO was shown the ammonia recovery rate of 18% with aeration and 11% with NaOH. At low temperature of $6-8^{\circ}C$ with the animal wastewater from piglet stall, the recovery rate of SP was shown 95% with NaOH and 92% with aeration using $MgCl_2$. The recovery rate of ammonia nitrogen was shown 9% with NaOH and 12% with aeration, respectively. It was observed that the pH can be raised by aeration. The reaction was completed within 5 minutes and the struvite cristal structure was formed and could be observed with an electronic microscope.