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51. Uranium Extraction from Sea Water with Composite Adsorbents, (II)

Author

Hisao Yamashita, Fumito Nakajima, Ozawa Yoshihiro, and Toshifumi Murata

Subjects
Nuclear and High Energy Physics, Materials science, Inorganic chemistry, Oxide, chemistry.chemical_element, Uranium, Chloride, Ferrous, chemistry.chemical_compound, Adsorption, Nuclear Energy and Engineering, chemistry, Specific surface area, medicine, Titanium tetrachloride, Uranyl chloride, medicine.drug
Abstract

A composite hydrous oxide, prepared from the mixed solution of titanium tetrachloride and ferrous chloride by addition of sodium hydroxide solultion, was investigated because of its rather high uranium adsorption capacity and its magnetic property. Results obtained may lead to easier handling of adsorbent species in the extraction of uranium from sea water. The uranium adsorption capacity of the composite hydrous oxide was measured using sea water to which a small amount of uranyl chloride was added. The initial uranium concentration was 10.1 μg/l. Physical and chemical properties, such as specific surface area, mean pore radius and amount of surface OH groups, were also measured. The composite hydrous oxide was found to be composed mainly of relatively small particles of anatase and large particles of magnetite. Uranium adsorption capacity reaches its maximum when the precipitation temperatures are 50–70°C. The capacity of the composite hydrous oxide was found to be closely related to the mean pore size ...

Published
1979

52. Uranium Extraction from Sea Water with Composite Adsorbents, (IV)

Author

Hisao Yamashita, Toshifumi Murata, Fumito Nakajima, and Ozawa Yoshihiro

Subjects
inorganic chemicals, Nuclear and High Energy Physics, Materials science, Precipitation (chemistry), Inorganic chemistry, Extraction (chemistry), Composite number, technology, industry, and agriculture, Oxide, chemistry.chemical_element, Uranium, equipment and supplies, Mole fraction, complex mixtures, chemistry.chemical_compound, Adsorption, Nuclear Energy and Engineering, chemistry, Titanium, Nuclear chemistry
Abstract

Composite hydrous titanium(IV)-iron(II) oxides prepared by precipitation from homogeneous solutions were studied with a view to developing magnetic adsorbents for uranium extraction from sea water. Higher uranium adsorption capacity was registered with homogeneous than with heterogeneous solution used for preparing the oxide. The adsorbents for uranium prepared from homogeneous solution moreover were found to require the copresence of urea and a suitable anion such as SO2- 4, in order to provide strongly active adsorption of uranium. The value of saturated magnetization of the composite hydrous oxides decreased with increasing titanium mole fraction up to 0.75, increase of the titanium mole fraction had, on the other hand, the effect of enhancing uranium adsorption capacity, which however saturated beyond 0.75 titanium mole fraction. The change of enthalpy brought by the uranium adsorption on the composite hydrous titanium (IV)-iron (II) oxides was 10 kcal/mol, and the amount of change independent of the ...

Published
1980

53. Extraction of Uranium from Seawater Using Magnetic Adsorbents

Author

T. Murata, Ozawa Yoshihiro, F. Nakajima, H. Yamashita, and K. Fujita

Subjects
inorganic chemicals, Hydrometallurgy, Chemistry, Process Chemistry and Technology, General Chemical Engineering, Extraction (chemistry), Inorganic chemistry, technology, industry, and agriculture, chemistry.chemical_element, Filtration and Separation, General Chemistry, Actinide, Uranium, Extractive metallurgy, equipment and supplies, complex mixtures, Adsorption, Desorption, Seawater
Abstract

A new process for the extraction of uranium from seawater was developed. In the process, uranium adsorption is effected using powdered magnetic adsorbents; the adsorbents are then separated from seawater using magnetic separation technology. This process is superior to a column method using a granulated hydrous titanium oxide adsorber bed in the following ways: (1) a higher rate of adsorption is realized because smaller particles are used in the uranium adsorption; and (2) blocking, which is inevitable in an adsorber bed, is eliminated. The composite hydrous titanium-iron oxide as a magnetic adsorbent having high uranium adsorption capacity and magnetization can be prepared by adding urea to a mixed solution of titanium sulfate and ferrous sulfate. Adsorption and desorption of uranium and the removal of the adsorbent using a small-scale uranium extraction plant (about 15 m3/d) is reported, and the feasibility of uranium extraction from seawater by this process is demonstrated.

Published
1981

54. The Collection of Uranium from Sea Water with Hydrous Metal Oxide. III. The Effects of Diverse Ions in Sea Water on Uranium Adsorption by Hydrous Titanium(IV) Oxide

Author

Hisao Yamashita, Ozawa Yoshihiro, Toshifumi Murata, and Fumito Nakajima

Subjects
inorganic chemicals, Magnesium, Inorganic chemistry, technology, industry, and agriculture, chemistry.chemical_element, General Chemistry, Uranium, Calcium, complex mixtures, chemistry.chemical_compound, Adsorption, Calcium carbonate, chemistry, Specific surface area, Carbonate, Fluoride, Nuclear chemistry
Abstract

The effect of diverse ions present in sea water on the uranium adsorption is elucidated in the present paper. The uranium-adsorption experiments were conducted using sea water and a solution containing 0.72 mol dm−3 NaCl and 2.3×10−3 mol dm−3 NaHCO3. The uranium uptake was about ten times larger from the NaCl–NaHCO3 solution than from sea water. The ions which depressed the uranium uptake were the calcium, magnesium, and fluoride present in sea water. Among these ions, calcium had the largest effect on the uranium uptake. The analysis of calcium and carbonate in the adsorbent after the adsorption experiment has revealed that the molar ratio between calcium and carbonate was about one. It was considered that calcium carbonate was deposited on the adsorbent during the uranium adsorption. The specific surface area and the pore volume decreased after the deposition of calcium carbonate. It was supposed that the decrease in the uranium uptake was caused by the coverage of the surface of hydrous titanium(IV) ox...

Published
1980

55. The Triflic Acid-Catalysed Deacylation and Decarboxylation of Polymethylbenzenecarbonyl Derivatives under Mild Conditions

Author

Takashi Keumi, Ozawa Yoshihiro, Hidehiko Kitajima, and Toshio Morita

Subjects
Steric effects, chemistry.chemical_compound, Chemistry, Decarboxylation, Boiling, Organic chemistry, General Chemistry, Triflic acid, Catalysis
Abstract

Sterically hindered acylarenes are deacylated to arenes in good yields on heating in boiling 1,2-dichloroethane containing a catalytic amount of triflic acid and water. Hindered arenecarboxylic acids undergo decarboxylation under the same conditions to give arenes in high yields.

Published
1989

56. AMPEROMETRIC GAS SENSOR USING SOLID STATE PROTON CONDUCTOR SENSITIVE TO HYDROGEN IN AIR AT ROOM TEMPERATURE

Author

Miura, Norio, Kato, Hiroshi, Ozawa, Yoshihiro, Yamazoe, Noboru, and Seiyama, Tetsuro

Abstract

A new type of amperometric gas sensor using a proton conductor (antimonic acid) and its working mechanisms are proposed for detecting small amounts of H2in air at room temperature. The short circuit current of the sensor cell was found to be proportional to the concentration of H2. It is also shown that the sensor could be modified into a simpler construction where the reference gas (air) is no longer necessary.

Published
1984
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57. PROTON CONDUCTION IN ANTIMONIC ACID AT MEDIUM TEMPERATURES IN THE PRESENCE OF WATER VAPOR

Author

Ozawa, Yoshihiro, Miura, Norio, Yamazoe, Noboru, and Seiyama, Tetsuro

Abstract

Antimonic acid was found to exhibit a relatively high proton conductivity at medium temperatures of 100–300 °C in the presence of water vapor. For example, the conductivity as high as 1×10−4S·cm−1could be maintained for 8 h at 200 °C under the water vapor pressure of 13 kPa. This stable conductivity at medium temperature was found to be attributable to the thermal stability of the water of constitution of Sb2O5·2H2O.

Published
1983
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58. The Collection of Uranium from Sea Water with Hydrous Metal Oxide. II. The Mechanism of Uranium Adsorption on Hydrous Titanium(IV) Oxide

Author

Yamashita, Hisao, Ozawa, Yoshihiro, Nakajima, Fumito, and Murata, Toshifumi

Abstract

The mechanism of uranium adsorption from sea water by hydrous titanium(IV) oxide was investigated. The uranium adsorption experiments were conducted using a solution containing NaCl, NaHCO3, and uranium. Thermochemical calculation showed that the tris(carbonato)dioxouranate(VI) ion [UO2(CO3)3]4−found in sea water existed in the solution at pH 8 and 25 °C. The uranium uptake varied with the pH of the solution, exhibiting a minimum value at pH 8. The enthalpy change, ΔH, and the activation energy, E, of the uranium adsorption were found to be 23.6 kJ mol−1and 52.7 kJ mol−1respectively. The analysis of carbonate in the adsorbent showed that the carbonate ion in [UO2(CO3)3]4−was released into the solution during the uranium adsorption. On the basis of the present experimental results, the mechanism of uranium adsorption was discussed.

Published
1980
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59. The Collection of Uranium from Sea Water with Hydrous Metal Oxide. IV. Physical Properties and Uranium Adsorption of Hydrous Titanium(IV) Oxide

Author

Yamashita, Hisao, Ozawa, Yoshihiro, Nakajima, Fumito, and Murata, Toshifumi

Abstract

The adsorption of uranium from sea water with hydrous titanium(IV) oxide(HTO) was studied. HTO was prepared by mixing titanium(IV) chloride and aqueous ammonia at different pHs and temperatures. The fundamental property of HTO was investigated for apparent crystal size, specific surface area, and pore size. The uranium uptake of HTO was found to depend more strongly on the temperature than on the pH in the preparation. HTO prepared at higher temperatures exhibited larger pores and a higher uranium uptake. A kinetic study of the uranium adsorption revealed that the rate of adsorption was controlled by the particle diffusion. The diffusion coefficients were calculated.

Published
1980
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60. The Collection of Uranium from Sea Water with Hydrous Metal Oxide. III. The Effects of Diverse Ions in Sea Water on Uranium Adsorption by Hydrous Titanium(IV) Oxide

Author

Yamashita, Hisao, Ozawa, Yoshihiro, Nakajima, Fumito, and Murata, Toshifumi

Abstract

The effect of diverse ions present in sea water on the uranium adsorption is elucidated in the present paper. The uranium-adsorption experiments were conducted using sea water and a solution containing 0.72 mol dm-3NaCl and 2.3×10-3mol dm-3NaHCO3. The uranium uptake was about ten times larger from the NaCl–NaHCO3solution than from sea water. The ions which depressed the uranium uptake were the calcium, magnesium, and fluoride present in sea water. Among these ions, calcium had the largest effect on the uranium uptake. The analysis of calcium and carbonate in the adsorbent after the adsorption experiment has revealed that the molar ratio between calcium and carbonate was about one. It was considered that calcium carbonate was deposited on the adsorbent during the uranium adsorption. The specific surface area and the pore volume decreased after the deposition of calcium carbonate. It was supposed that the decrease in the uranium uptake was caused by the coverage of the surface of hydrous titanium(IV) oxide with calcium carbonate. Magnesium ions depressed the uranium uptake in the same manner as calcium ions. The effect of the magnesium ions, however, was relatively small compared with that of the calcium ions.

Published
1980
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62. ChemInform Abstract: THE COLLECTION OF URANIUM FROM SEA WATER WITH HYDROUS METAL OXIDE. II. THE MECHANISM OF URANIUM ADSORPTION ON HYDROUS TITANIUM(IV) OXIDE

Author

Toshifumi Murata, Fumito Nakajima, Ozawa Yoshihiro, and Hisao Yamashita

Subjects
Inorganic chemistry, Enthalpy, Oxide, chemistry.chemical_element, General Medicine, Uranium, Metal, chemistry.chemical_compound, Adsorption, chemistry, visual_art, visual_art.visual_art_medium, Carbonate, Carbonate Ion, Titanium
Abstract

The mechanism of uranium adsorption from sea water by hydrous titanium(IV) oxide was investigated. The uranium adsorption experiments were conducted using a solution containing NaCl, NaHCO3, and uranium. Thermochemical calculation showed that the tris(carbonato)dioxouranate(VI) ion [UO2(CO3)3]4− found in sea water existed in the solution at pH 8 and 25 °C. The uranium uptake varied with the pH of the solution, exhibiting a minimum value at pH 8. The enthalpy change, ΔH, and the activation energy, E, of the uranium adsorption were found to be 23.6 kJ mol−1 and 52.7 kJ mol−1 respectively. The analysis of carbonate in the adsorbent showed that the carbonate ion in [UO2(CO3)3]4− was released into the solution during the uranium adsorption. On the basis of the present experimental results, the mechanism of uranium adsorption was discussed.

Published
1980

63. Authors

Author

Galperin, Alex, primary, Segev, Meir, additional, Radkowsky, Alvin, additional, Pei, B. S., additional, Chen, Y. B., additional, Shih, Chunkuan, additional, Lin, W. S., additional, Hida, Kazuki, additional, Kusuno, Sadao, additional, Seino, Takeshi, additional, Geldard, John F., additional, Beyerlein, Adolph L., additional, Chiu, Houn-Lin, additional, McGrail, B. P., additional, Matsuda, Masami, additional, Funabashi, Kiyomi, additional, Nishi, Takashi, additional, Yusa, Hideo, additional, Kikuchi, Makoto, additional, Rao, P. Bhaskar, additional, Singh, Om Pal, additional, Sohal, Manohar S., additional, Lee, Jae Young, additional, No, Hee Cheon, additional, Uda, Tatsuhiko, additional, Otsuka, Hisao, additional, Ozawa, Yoshihiro, additional, Sulima, Romuald, additional, Clayton, Eugene D., additional, Clark, Hugh K., additional, Walker, Gordon, additional, and Libby, Richard A., additional

Published
1986
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67. NIPPON KAGAKU KAISHI

Author

OZAWA, Yoshihiro, primary, MIURA, Norio, additional, YAMAZOE, Noboru, additional, and SEIYAMA, Tetsuro, additional

Published
1983
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68. NIPPON KAGAKU KAISHI

Author

YAMASHITA, Hisao, primary, OZAWA, Yoshihiro, additional, NAKAJIMA, Fumito, additional, and MURATA, Toshifumi, additional

Published
1978
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71. Authors

Author

Wood, Bernard J., primary, Beall, Gary W., additional, Allard, Bert, additional, Wood, Marcus I., additional, Coons, William E., additional, Brookins, Douglas G., additional, Schreiner, Felix, additional, Fried, Sherman, additional, Friedman, Arnold M., additional, Hawthorne, J. Russell, additional, Main, Alan P., additional, Shriver, Bryce L., additional, Pachur, Dieter, additional, Keller, Herbert W., additional, Shallen, John M., additional, Iiollein, David A., additional, Carl Hott, A., additional, Kiefhaber, Edgar, additional, Möckel, Hermann J., additional, Köster, Rainer H., additional, Uchida, Shunsuke, additional, Ozawa, Yoshihiro, additional, Ibe, Eishi, additional, Weguro, Yoshinorit, additional, Ilejna, J., additional, Mantlik, F., additional, Antonov, Angel, additional, Bogdzel, Andrej A., additional, Gledenov, Yuri] M., additional, Tishin, Viacheslav G., additional, and Akatsu, Eiko, additional

Published
1982
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80. Authors

Author

Davidson, William M., primary, Morimoto, Alan K., additional, Moya, Mary M., additional, Schoeneman, J. Lee, additional, Thunborg, Siegfried, additional, Starr, Gregory P., additional, Sami, Samir M., additional, Tran, C., additional, Hsu, Mo-chen, additional, Naito, Norio, additional, Sakuma, Akira, additional, Shigeno, Kei, additional, Mori, Nobuyuki, additional, Ha, Jae-Joo, additional, Aldemir, Tunc, additional, Hussein, Fahmy M., additional, Obeid, Mohamed A., additional, El-Malahy, Khalid S., additional, Binney, Stephen E., additional, Harris, Richard D., additional, Uda, Tatsuhiko, additional, Ozawa, Yoshihiro, additional, Iba, Hajime, additional, Wanner, Hans, additional, Tallent, Othar K., additional, McDaniel, Earl W., additional, Dodson, Karen E., additional, Godsey, Terry T., additional, Murray, Alexander P., additional, Braester, Carol, additional, Thunvik, Roger, additional, Kim, Hyong Chol, additional, Hsiao, Ming-Yuan, additional, and Levine, Samuel H., additional

Published
1987
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81. Authors

Author

Cubicciotti, Daniel, primary, Sehgal, Bal Raj, additional, Williford, R. E., additional, Uetake, Naohito, additional, Ozawa, Yoshihiro, additional, Kikuchi, Makoto, additional, Ratigan, Joe L., additional, Saltelli, A., additional, Avogadro, A., additional, Bidoglio, G., additional, Thunvik, Roger, additional, Braester, Carol, additional, Panno, S. V., additional, Soo, P., additional, Zijp, Willem L., additional, Zsolnay, Éva M., additional, Nolthenius, Henk J., additional, Szondi, Egon J., additional, Verhaag, Gerardus C. H. M., additional, Manno, Vincent P., additional, Golay, Michael W., additional, Cronenberg, August W., additional, Croucher, Douglas W., additional, MacDonald, Phililp E., additional, Schrack, Roald A., additional, and Nason, Randall R., additional

Published
1984
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85. HYDROGEN SEPARATION WITH ELECTROCHEMICAL CELL

Author

Miura, Norio, Ozawa, Yoshihiro, Yamazoe, Noboru, and Seiyama, Tetsuro

Abstract

A new technique for hydrogen separation using a short-circuited electrochemical cell constructed by use of a solid electrolyte was described with preliminary experimental data. With phosphomolybdic acid as a proton conductor, a short-circuit current density of 7.4 mA/cm2or a rate of hydrogen separation of 3.1 cm3/h·cm2-electrode, was attained experimentally.

Published
1980
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86. [Case Report; A case of cibenzoline abuse was diagnosed by its loading].

Author

Morishita K, Toyoshima T, Sano N, Harada H, Osawa M, Watanabe T, Handa M, Ozawa Y, and Matsunaga H

Subjects
Aged, 80 and over, Blood Glucose analysis, Fasting physiology, Female, Humans, Mental Disorders diagnosis, Treatment Outcome, Anti-Arrhythmia Agents adverse effects, Imidazoles adverse effects, Mental Disorders drug therapy
Published
2015
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87. Bovine spongiform encephalopathy in Japan and options for control.

Author

Ozawa Y

Abstract

Since September 2001, Japan has reported to the World Organisation for Animal Health (OIE: Office International des Epizooties) 31 cases of typical bovine spongiform encephalopathy (BSE) and two atypical cases. There were at least two major exposure episodes in Japan. The first, attributed mainly to imported contaminated feed ingredients, occurred between 1995 and 1996 and 13 affected Holstein cows (Group A) were detected in different parts of Japan. The second exposure occurred in Hokkaido, the northernmost island of Japan, between 1999 and 2000. To date, 14 BSE cases (Group B) have been found there. All positive cases of Groups A and B were Holstein cows. The remaining four cases (Group C) were of various ages, including one atypical case of 169-month-old native beef cattle, but the sources of infection are not yet known. Two young (21- and 23-month-old) Holstein steers are also included in Group C, but the transmissibility of these cases has not been confirmed. It appears unique that all confirmed typical BSE cases in Japan have been in Holstein cows, and it could be suggested that future surveillance of BSE in Japan should be focused solely on Holstein cows. It is also suggested that Japan be divided into two zones; Hokkaido zone and the rest. In this way, different strategies could be implemented to achieve eradication within shorter periods of time in respective zones. Since the youngest typical BSE case confirmed in Japan was a 48-month-old cow belonging to Group B, it is suggested that the age of the cattle to be tested at abattoirs be raised from 20 months to 30 months and older. So far, two so-called 'atypical' cases of BSE have been found in Japan, and the author proposes that it is necessary to demonstrate the transmissibility of these cases in order to confirm that they are indeed transmissible spongiform encephalopathies. Further, the author considers it necessary to compare the standards of the national diagnostic laboratory that tests healthy cattle in Japan with those of other OIE BSE reference laboratories in order to demonstrate that current Japanese diagnostic practices meet international standards.

Published
2007

88. [BSE and problems with food safety measures in Japan].

Author

Ozawa Y

Subjects
Animals, Cattle, Creutzfeldt-Jakob Syndrome prevention & control, Encephalopathy, Bovine Spongiform transmission, Food Handling standards, Humans, Japan, Safety, Encephalopathy, Bovine Spongiform prevention & control, Meat
Published
2005

89. [Placement of an ultraflex nitinol stent for severe tracheobronchial obstruction in a case of relapsing polychondritis].

Author

Miyazaki H, Shimane S, Morita S, Yamada T, Ida M, Ozawa Y, Nagayama M, Iwakiri S, Chihara K, and Hirata T

Subjects
Alloys, Bronchoscopy, Humans, Male, Middle Aged, Tracheal Stenosis etiology, Polychondritis, Relapsing complications, Stents, Trachea surgery, Tracheal Stenosis surgery
Abstract

A 59-year-old man, who had been treated for bronchial asthma since 2000, was hospitalized with high fever and productive cough in November 2003. Chest radiography on admission showed consolidations in both lower lung fields, and computed tomography demonstrated anteroposterior narrowing of both main bronchi. A physical examination revealed deformity of auricular cartilage and saddle nose, and we diagnosed him relapsing polychondritis (RP). When he was readmitted 4 months later because of severe tracheobronchial stenosis and respiratory failure he required mechanical ventilation, but it was difficult to wean him from the ventilator. Self-expandable metallic stents were placed in the left main bronchus and the trachea. After the procedure, he was successfully weared from mechanical ventilation. Since airway complications of RP can be fatal, stent implantation should be considered in the management of RP with airway manifestations.

Published
2005

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