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41.
Sulfide glasses have been considered as new anode materials for lithium-ion batteries because their high ionic conductivity (approximately ≥10−4 S/cm) (more than one order of magnitude higher than oxide glasses (approximately ≤10−6 S/cm)) was expected to accelerate Li+ ion insertion into and extraction from anode materials during charge and discharge reactions. This intrinsic property can yield the reversible lithium-alloying reaction by minimizing the aggregation of lithium-alloy phases leading to the improvement of cycling behavior. To examine sulfide glasses as new anode materials, GeS2 glass was chosen for study in this work due to its stability in air-atmospheres. The electrochemical properties of the GeS2 glass were compared with those of the Ge metal and GeO2 glass. The initial insertion of lithium into the GeX2 (X = O, S) glasses leads to the formation of Li2X (X = O, S) phases associated with the irreversible capacity on the first cycle. The improved reversibility of the reaction of lithium with Ge was observed in the Li2S medium rather than Li2O one, which leads to the improvement of cycle performance in the GeS2 glass anode. 相似文献
42.
采用色谱-质谱-红外(GC-MS-IR)三联仪,分析了新型齿轮油复合添加剂中硫化合物的种类、组成和结构,结合系统计算机自动检索功能,研究结果表明该硫化合物主要由二硫化物、三硫化物组成,烷烃的结构为叔丁基。 相似文献
43.
L. A. Zemnukhova N. P. Morgun M. A. Tsvetnov A. V. Kovekhova 《Journal of Sulfur Chemistry》2017,38(4):401-420
Sulfide ions are among the most common pollutants in natural waters. Sulfide sorption methods are widely used in the waste water treatment practice. The most promising sorbents for removing sulfide ions are porous carbon materials. In the present study we researched sorption capacity of the carbon- and silicon-containing samples of rice and buckwheat processing wastes, as well as the activated carbon, carbon fiber, chitosan and natural silicates toward the sulfide ions in aqueous solutions. It was found that the most effective sorbent from the studied ones is the carbon fiber Aktilen B (99%) and from plant wastes – carbonaceous sorbents obtained from rice straw (77–98%) and buckwheat (94%). We studied the physico-chemical and structural properties of the carbonaceous sorbent based on rice straw and it was found that this sample is amorphous and has a predominant microporous structure. At the concentration of sulfide ions ranging from 140 to 800?µg?l?1, the studied sorbent reduces the amount of sulfide ions to 0.4–1.4 of the maximum permissible concentration and can be used for treating natural and post-treating waste waters. 相似文献
44.
45.
Z. K. Kun D. Leksell P. R. Malmberg J. Murphy L. J. Sienkiewicz 《Journal of Electronic Materials》1981,10(1):287-300
Comparative experiments showed that the addition of chlorine at the preparation of the ZnS:Mn source materials for TFEL device
fabrication can enhance grain growth in the ZnS:Mn films during post-deposition anneal. Correspondingly the luminescent properties
of these films improved as compared to those without chlorine. Depending upon the Mn concen-tration and annealing temperature,
both the saturation brightness and the peak luminous efficiency have increased by up to a factor of three. Optimized experimental
para-meters resulted 810fL saturation brightness and 0.6l/W peak luminous efficiency. A practical significance is that useful
TFEL devices can be fabricated using source materials with Cl, addition when post deposition annealing temperatures have to
be kept low. 相似文献
46.
Removal of malodorous organic sulfides with molecular oxygen and visible light over metal phthalocyanine 总被引:2,自引:0,他引:2
Organic sulfides are malodorous compounds in environment. In this work, deodorization of model substrates, methyl phenyl sulfide, 2-mercaptobenzoic acid and benzyl 2-propenyl sulfide, have been studied in an aerated methanolic aqueous solution under visible light irradiation (lambda>450nm), using metal phthalocyanine sulfonate (MPcS, M=Al, Pd) as a photocatalyst. The result shows that all the representative sulfides could be efficiently oxidized, with concomitant formation of sulfoxide and sulfone as the main products. Kinetic study using sodium azide and benzoquinone as reactive species scavenger reveals that the sulfide oxidation is mainly initiated by singlet oxygen. It is also observed that the rate of sulfide oxidation increases with increasing the water content in the mixed solvent. Recycle experiments with immobilized PdPcS on organoclay or immobilized AlPcS on anionic resin demonstrates that the sensitizer could be repeatedly used, without significant loss in the photosensitization activity. 相似文献
47.
Controlling sulfide (H2S) production and emission in sewer systems is critical due to the corrosion and malodour problems that sulfide causes. Chemical dosing is one of the most commonly used measures to mitigate these problems. Many chemicals have been reported to be effective for sulfide control, but the extent of success varies between chemicals and is also dependent on how they are applied. This industry survey aims to summarise the current practice in Australia with the view to assist the water industry to further improve their practices and to identify new research questions. Results showed that dosing is mainly undertaken in pressure mains. Magnesium hydroxide, sodium hydroxide and nitrate are the most commonly used chemicals for sewers with low flows. In comparison, iron salts are preferentially used for sulfide control in large systems. The use of oxygen injection has declined dramatically in the past few years. Chemical dosing is mainly conducted at wet wells and pumping stations, except for oxygen, which is injected into the pipe. The dosing rates are normally linked to the control mechanisms of the chemicals and the dosing locations, with constant or profiled dosing rates usually applied. Finally, key opportunities for improvement are the use of mathematical models for the selection of chemicals and dosing locations, on-line dynamic control of the dosing rates and the development of more cost-effective chemicals for sulfide control. 相似文献
48.
49.
本文叙述了用电解精炼法在制备高纯铅过程中,降低铜、铋、锡杂质含量的各种措施和试验结果,比较详细地介绍了用硫化法降低电解液中的铜、铋、锡杂质的新工艺。 相似文献
50.
Villa-Gomez D Ababneh H Papirio S Rousseau DP Lens PN 《Journal of hazardous materials》2011,192(1):200-207
The effect of the sulfide concentration on the location of the metal precipitates within sulfate-reducing inversed fluidized bed (IFB) reactors was evaluated. Two mesophilic IFB reactors were operated for over 100 days at the same operational conditions, but with different chemical oxygen demand (COD) to SO42− ratio (5 and 1, respectively). After a start up phase, 10 mg/L of Cu, Pb, Cd and Zn each were added to the influent. The sulfide concentration in one IFB reactor reached 648 mg/L, while it reached only 59 mg/L in the other one. In the high sulfide IFB reactor, the precipitated metals were mainly located in the bulk liquid (as fines), whereas in the low sulfide IFB reactor the metal preciptiates were mainly present in the biofilm. The latter can be explained by local supersaturation due to sulfide production in the biofilm. This paper demonstrates that the sulfide concentration needs to be controlled in sulfate reducing IFB reactors to steer the location of the metal precipitates for recovery. 相似文献