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1.
The thermal stability of a FeF3 cathode was quantitatively studied by differential scanning calorimetry (DSC). The cycled electrode without electrolyte was examined and found to become more thermally stable after Li-ion insertion. On the other hand, mixtures of cycled electrodes and electrolyte were investigated by changing the ratio of cycled electrode to electrolyte. The thermal decomposition of the electrolyte was mainly responsible for the exothermic heat for the discharged electrode and electrolyte combination. Although a reaction between the active materials of the electrode and electrolyte was observed for the mixture of the charged electrode and electrolyte, the exothermic heats were small. In contrast to lithium transition-metal oxide cathodes for lithium-ion batteries, the exothermic heat was suppressed by the FeF3 electrode. Therefore, FeF3 as a cathode for Li-ion batteries shows more thermal stability at elevated temperatures. 相似文献
2.
In the present study, K2S and Bi2S3 were used as additives in electrolytes and electrodes, respectively. The effects of these additives on the electrochemical properties of nano-sized Fe2O3-loaded carbon electrodes were investigated using cyclic voltammetry (CV), galvanostatic cycling performance and scanning electron microscopy (SEM), along with electron dispersive spectroscopy (EDS). The results showed that both K2S and Bi2S3 significantly reduced hydrogen evolution and benefited the Fe2O3-loaded carbon electrode, such as by retarding passivation and improving the discharge capacity. The effects of metal sulfide additives depended on the carbon used. For Bi2S3 additive, all carbons provided larger capacities than acetylene black (AB) while AB gave greater capacity than other carbons when K2S was used. 相似文献
3.
Kazuhiko Takeuchi Taka-aki Hanaoka Takehiko Matsuzaki Yoshihiro Sugi Shigeto Ogasawara Yoshimoto Abe Takahisa Misono 《Catalysis Today》1994,20(3):423-435
An in situ diffuse reflectance FT-IR technique was employed to investigate the active surface species and the reaction mechanism of the oxygenate formation in the vapor phase hydroformylation of ethene on Co/SiO2 promoted with various noble metals such as Ir, Rh, Pt, Re, Ru, and Pd. Co(A)/SiO2 and Ir(CO)/SiO2 which were derived from cobalt(II) acetate and Ir4(CO)12, respectively, were quite inactive in the reaction, and showed only quite small peaks of adsorbed CO under the conditions of 1.1 MPa of C2H4/CO/H2 at 298 K. In contrast, Co(A)-Ir(CO)/SiO2, which were very active in the reaction, exhibited strong absorption bands of linear and bridged CO species. At 423–463 K, propanal adsorbed on the catalyst and acyl species which is suggested as the intermediate for the formation of propanal were also observed on this catalyst. By exposing CO preadsorbed on this catalyst to C2H4/H2 at 289 K and 0.1 MPa, the intensity of the linear CO band decreased, and the bands of propanal and acyl species emerged simultaneously, whereas that of the bridged CO band remained constant after the initial drop. These results suggested that the oxygenates are formed via the CO insertion into adsorbed ethyl species, and linear CO species plays a major role in the CO insertion on these noble metal-promoted cobalt catalysts. 相似文献
4.
Manabu Nishijima Irina D. Gocheva Shigeto Okada Takayuki Doi Jun-ichi Yamaki Tetsuaki Nishida 《Journal of power sources》2009,190(2):558-562
Fluorine compounds have high discharge voltage due to its highly ionic metal-ligand bonds. In them, perovskite-type metal trifluorides with corner sharing matrix have large bottlenecks of diffusion pathways for intercalants. Iron trifluoride composites (FeF3-C) prepared by planetary ball milling with carbon showed reversible charge/discharge behavior not only for Li, but also for Na anodes. X-ray diffraction and 57Fe Mössbauer spectroscopy were applied to characterize the electrochemical properties of FeF3 vs. Li and Na anodes. The cathode performances of the other commercially available transition metal trifluorides such as MF3 (M = Ti, V, Mn, Co) have been also investigated. 相似文献
5.
Noriaki Kurita Norihiko Fukatsu Teruo Ohashi Satoshi Miyamoto Fumiaki Sato Hiroyuki Nakai Kazuhiko Irie 《Metallurgical and Materials Transactions B》1996,27(6):929-935
We have developed a hydrogen sensor for in situ measurements of hydrogen activities in molten copper. The sensor consists of a concentration cell utilizing a proton conductor,
CaZr0.9In0.1O3-δ, as the solid electrolyte. The electromotive force (emf) of the cell was generated by both hydrogen and oxygen activity gradients
across the cell in a high-temperature region simulating the fire refining processes of copper. However, accurate hydrogen
activity in molten copper could be evaluated from the emf if oxygen activity in molten copper was determined simultaneously
by another concentration cell and if the hydrogen and the oxygen activities at the reference electrode were known. The performance
of the sensor was studied under various conditions. The observed good response and reliability of the sensor show that it
should be a powerful tool for improvement of the fire refining process of the molten copper. Theoretical treatment of the
calculation of the emf of the concentration cells using a mixed ionic conductor, i.e., protonic and oxide ionic conductor, as solid electrolytes is also discussed briefly. 相似文献
6.
A Phytol‐Enriched Diet Activates PPAR‐α in the Liver and Brown Adipose Tissue to Ameliorate Obesity‐Induced Metabolic Abnormalities 下载免费PDF全文
7.
Larisa S. Plashnitsa Eiji Kobayashi Shigeto Okada Jun-ichi Yamaki 《Electrochimica acta》2011,56(3):1344
Lithium vanadium fluorophosphate, LiVPO4F, was utilized as both cathode and anode for fabrication of a symmetric lithium-ion LiVPO4F//LiVPO4F cell. The electrochemical evolution of the LiVPO4F//LiVPO4F cell with the commonly used organic electrolyte LiPF6/EC-DMC has shown that this cell works as a secondary battery, but exhibits poor durability at room temperature and absolutely does not work at increased operating temperatures. To improve the performance and safety of this symmetric battery, we substituted a non-flammable ionic liquid (IL) LiBF4/EMIBF4 electrolyte for the organic electrolyte. The symmetric battery using the IL electrolyte was examined galvanostatically at different rates and operating temperatures within the voltage range of 0.01–2.8 V. It was demonstrated that the IL-based symmetric cell worked as a secondary battery with a Coulombic efficiency of 77% at 0.1 mA cm−2 and 25 °C. It was also found that the use of the IL electrolyte instead of the organic one resulted in the general reduction of the first discharge capacity by about 20–25% but provided much more stable behavior and a longer cycle life. Moreover, an increase of the discharge capacity of the IL-based symmetric battery up to 120 mA h g−1 was observed when the operating temperature was increased up to 80 °C at 0.1 mA cm−2. The obtained electrochemical behavior of both symmetric batteries was confirmed by complex-impedance measurements at different temperatures and cycling states. The thermal stability of LiVPO4F with both the IL and organic electrolytes was also examined. 相似文献
8.
BACKGROUND: To improve the poor prognosis of patients with advanced incurable gastric cancer, intensive chemotherapy combined with radical surgery was used. PATIENTS AND METHODS: Thirty patients with incurable gastric cancer were treated with a combination of 5-fluorouracil (370 mg/m2) and leucovorin (30 mg/person), given intravenously for five consecutive days, followed by cisplatinum (70 mg/m2) and etoposide (70 mg/m2) on days 6 and 20, delivered through a catheter placed either in the aorta with its tip at the level of the ninth thoracic vertebra or in the celiac artery. This treatment (FLEP therapy) was repeated twice every 5 weeks. Radical or palliative surgery followed chemotherapy. RESULTS: The overall response rate to the chemotherapy was 50.0% (15 of 30 patients, 95% confidence limit 0.305-0.671). Nineteen patients (15 with a partial response, three showing no change, and one with progressive disease) underwent surgery. Of these, nine underwent curative surgery and 10 palliative surgery. The median survival time was 6.5 months overall, 12.7 months for responders, and 4.7 months for nonresponders. Long-term survivors were exclusively found among patients with distant lymph node metastasis treated by curative surgery (55.6% at 5 years). CONCLUSIONS: Favorable results of this small phase II study justify a phase III trial. 相似文献
9.
M Hayashi S Takizawa N Fukatsu I Imamura K Shimura I Horii 《Canadian Metallurgical Quarterly》1995,20(3):281-296
The toxicity of Etretinate, a retinoid compound, on the male reproductive system was studied in male rats. The drug was administered for four weeks at the dose levels of 0 (control: Vehicle, Peanut oil), 5 and 25 mg/kg/day. The animals were then allowed to mate, and their male reproductive functions and organs were examined in detail. No significant changes due to toxicity were observed in male reproductive functions and organs in the 5 mg/kg/day group after the 4-week treatment. In contrast, males in the 25 mg/kg/day group showed drug-related changes in their reproductive performance (decrease of mating ability and fertility rate), testosterone blood level, sperm head counts, sperm viability and number in the caudal epididymis, organ weight and in the histopathology of their reproductive organs (atrophy of seminiferous tubules, necrosis of spermatocytes and spermatids, vacuolation of nuclei of spermatocytes and spermatids). Even though Etretinate belong to the retinoid group of compounds, the changes seen in the 25 mg/kg/day group were almost the same as those observed in Vitamin A-deficient animals. In conclusion, there is a correlation between changes due to toxicity observed for parameters of male fertility and for histopathological evaluation of the testis of rats that receiving high dose, treatment with Etretinate for 4 weeks. 相似文献
10.
A high frequency model of transformer winding is used to analyze the voltage oscillations due to various excitations such as the very fast transient overvoltage which occurs at the time of disconnecting switch operations. Usually, a circuit of interlinked inductances and capacitances is used for this purpose, in which circuit parameters have to be properly determined. Previously, those constants have been estimated taking the coil section pair as a unit. In the method proposed here, the section pair can be further subdivided. The time‐domain calculation is conducted combining the frequency analysis and FFT technique. The voltage oscillations of the winding subjected to the lightning impulse are calculated. The correspondence with the experimental results is satisfactory. The response to a chopped impulse shows this method's applicability to high frequency analysis. Since the constants are calculated directly from the design parameters of transformer winding, this technique is particularly useful in developing and designing transformers. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 146(3): 8–16, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10280 相似文献