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排序方式: 共有757条查询结果,搜索用时 31 毫秒
1.
Y Terashima H Ozaki R R Giri T Tano S Nakatsuji R Takanami S Taniguchi 《Water science and technology》2006,54(8):55-63
Environmental pollution by low concentrations of 2,4-Dichlorophenoxyacetic acid (2,4-D) is a concern these days due to ever increasingly stringent regulations. Photocatalysis with immobilized TiO2 fiber is a promising oxidation method. Laboratory experiments on photocatalytic degradation of 0.045 mmol l(-1) 2,4-D with the world's first high-strength TiO2 fiber catalyst were carried out in a continuous flow reactor in which the degradations were, in general, similar to those with high 2,4-D concentrations investigated elsewhere. Degradation and mineralization of 2,4-D were significantly enhanced with no initial pH adjustments. The rate constants for total organic carbon (TOC) without pH adjustment were about two-fold bigger than the pH adjustment cases. CO2 gas measurement and carbon mass-balance were carried out for the first time, where about 34% organic carbon converted into CO2 gas during four-hour oxidation. 2,4-Dichlorophenol (2,4-DCP), phenol, benzyl alcohol and two unknowns (RT = 2.65 and 3.78 min.) were detected as aromatic intermediates while Phenol was the new aromatic in HPLC analysis. Dechlorination efficiencies were high (> 70%) in all the cases, and more than 90% efficiencies were observed in chloride mass balance. Bigger flow rates and solution temperature fixed at 20 degrees C without pH adjustment greatly enhanced 2,4-D mineralization. These results can be an important basis in applying the treatment method for dioxin-contaminated water and wastewater. 相似文献
2.
Improved visible-light responsive photocatalytic activity of N and Si co-doped titanias 总被引:1,自引:0,他引:1
Thermal reaction of titanium tetraisopropoxide and tetraethyl orthosilicate in 1,4-butanediol afforded nanocrystalline silica-modified
titanias having large surface area and superior thermal stability. In this study, the thus-obtained silica-modified titanias
were treated in an NH3 flow at high temperatures, and their physical and photocatalytic properties were investigated. Compared with NH3-treated TiO2 without silica modification, the NH3-treated silica-modified titanias showed a stronger absorption in the visible region (400–500 nm) and had a larger peak at
396 eV in the N 1s XPS spectrum. These results indicate that a larger amount of nitrogen was stably doped in the silica-modified
titania. The obtained products exhibited a high photocatalytic activity for degradation of Rhodamine B and decomposition of
acetaldehyde under visible light irradiation.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
K. Fujii J. Fujimoto H. Hayashii R. Kajikawa Y. Masatani H. Ozaki A. Sugiyama R. Suzaki S. Suzuki T.Y. Tsukamoto T.F. Tsukamoto S. Uno S. Iwata 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1985,236(1):55-63
We constructed and tested a prototype gas sampling electromagnetic calorimeter of the Pb-proportional tube sandwich type. The calorimeter uses conductive plastic tubes and cathode pad readout with a tower structure which resulted in reasonable energy and spatial resolutions for electrons in the momentum range 0.5–4.0 GeV/c; /c). This paper describes the test and the performance studied under various conditions. 相似文献
4.
Endocrine disrupting chemicals (EDCs) are the focus of current environmental issues, as they can cause adverse health effects to animals and human, subsequent to endocrine function. The objective of this study was to remove a specific compound of EDCs (i.e. pentachlorophenol, C(6)OCL(5)Na, molecular weight of 288 g/mol) using low pressure reverse osmosis membrane (LPROM). A cross flow module of LPROM was used to observe the effects of operating parameters, i.e. pH, operating pressure and temperature. The design of the experiment was based on MINITAB(TM) software, and the analysis of results was conducted by factorial analysis. It was found that the rejection of pentachlorophenol was higher than 80% at a recovery rate of 60 to 70%. The rejection was subjected to increase with the increase of pH. The flux was observed to be increased with the increase of operating pressure and temperature. This study also investigated the interaction effects between operating parameters involved. 相似文献
5.
Lee S.B. Nakayama K. Matsui T. Ozaki M. Yoshino K. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2002,9(1):31-38
Silica particles dispersed in liquid crystals exhibit a novel behavior such as a unique migrating behavior and alignment. These characteristics are found to depend on the size of the nanoparticles, the surface state of nanoparticles, the liquid crystal (LC) phases, the amplitude and the frequency of applied voltage. These are discussed in terms of anisotropic particle-particle and particle-LC molecules interactions in the anisotropic environment of liquid crystal matrix 相似文献
6.
膨胀石墨对各种油类的吸附动力学 总被引:9,自引:1,他引:8
Michio INAGAKI Tomoya NAGATA Taisuke SUWA Masahiro TOYODA 《新型炭材料》2006,21(2):97-102
通过对吸附率(有效吸附系数)Ks和饱和吸附量msat的测量,描述了粘度为0.001 Pa·s~0.850 Pa·s的各种油类在膨胀石墨柱中的吸附动力学,发现吸附率Ks对油类粘度有很强的相关性.吸入膨胀石墨柱中的饱和吸附量msat几乎恒定在50kg/kg,该值略低于由膨胀石墨块直接浸渍在油中测得的吸附容量,这是由于所吸附的油沿膨胀石墨柱高度存在重力梯度. 相似文献
7.
M Ikeda K Noda M Hiura T Tamaya M Ozaki M Hatae M Ozawa T Yamabe K Tanaka R Izumi H Okada Y Ogita H Hoshiai 《Canadian Metallurgical Quarterly》1998,25(14):2249-2257
We conducted a multi-site late phase II trial of oral etoposide administered for 21 consecutive days in patients with cervical cancer in cooperation with 32 institutes. Fifty mg/body of oral etoposide was administered daily for 21 consecutive days. Treatment cycles were to be repeated at 4- to 5-week intervals. Eighty patients were enrolled and 70 patients were evaluated. The overall response rate (95% CI), including one complete response patient and 18 partial response patients, was 27.1% (19/70). The most commonly observed toxicity was myelosuppression such as leukopenia, neutropenia, hemoglobin decrease and thrombocytopenia. Other adverse effects were gastrointestinal toxicities such as anorexia, nausea, stomatitis and vomiting, as well as fatigue and alopecia. These adverse effects were well tolerated and controlled with medications. From these results we concluded oral etoposide administered for 21 consecutive days was an effective drug against cervical cancer. 相似文献
8.
Y Nakamura T Ozaki S Ichimiya A Nakagawara S Sakiyama 《Canadian Metallurgical Quarterly》1998,243(3):722-726
Retinoic acid (RA) plays a major role in neuronal cell differentiation. Neuroblastoma cells differentiate in vitro by extending neurites and forming ganglion-like aggregates in response to RA. In the present study, we have examined a biological role(s) of DAN in the regulation of RA-mediated cellular differentiation in neuroblastoma cells. RTBM1 and SH-SY5Y cells undergo marked morphological changes associated with a remarkable induction of DAN gene expression when exposed to RA. By transfecting an expression vector harboring a rat DAN cDNA into SH-SY5Y cells, we have obtained two independent transfectants which express a large amount of DAN. The forced expression of DAN gene enhanced the neurite extension in the presence of RA, suggesting that DAN gene product might contain some regulatory role(s) in the RA-induced cellular differentiation in neuroblastoma cells. 相似文献
9.
A screening test was undertaken to isolate a microorganism that produced 5-oxoprolinase (without ATP-hydrolyzing). The 5-oxoprolinase (without ATP-hydrolyzing) activity (decyclization activity toward L-pyroglutamate) was found in a cell-free extract of Alcaligenes faecalis N-38A, newly isolated from a soil sample. The enzyme was purified as a homogeneous preparation. The molecular weight of the enzyme was estimated to be 47,000. The decyclization activity was specific for L-pyroglutamate, and independent of ATP and metal ions. The reaction was a reversible one, i.e., cyclization reaction of L-glutamate to yield pyroglutamate was identified. 相似文献
10.
H Ieda S Naruse S Furuya T Ozaki E Ando K Nokihara S Hori M Kitagawa T Hayakawa 《Canadian Metallurgical Quarterly》1998,13(12):1225-1233
In order to identify proguanylin-secreting cells, we have raised an antiserum against the synthetic fragment of human proguanylin (1-15) and have examined the proguanylin-positive cells in the human and rat gastrointestinal tract by immunohistochemical methods. Numerous proguanylin (1-15)-immunoreactive cells were found in the gastrointestinal tract. They were either pyramidal or spindle shaped in the stomach. Spindle-shaped cells, frequently possessing long slender processes, were located at the base of the pyloric epithelium and did not extend to the lumen. In the duodenum and jejunum, these cells were mostly pyramidal in shape and often had a slender process towards the lumen. The immunostaining was completely blocked by the human proguanylin (1-15) fragment. Paneth and goblet cells were negative against this antiserum. The number of serotonin-positive cells was much larger than that of proguanylin-positive cells in all the segments tested. The number of proguanylin-positive cells decreased from the jejunum to the ileum and very few cells were observed in the colon. In contrast to serotonin-positive cells, most somatostatin-positive cells were also positive for proguanylin. Thus, proguanylin (1-15) or its related protein appears to coexist with somatostatin in intestinal endocrine D cells which may be a source of circulating proguanylin. Proguanylin, like somatostatin, may also regulate intestinal function as a local regulator. 相似文献