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排序方式: 共有2219条查询结果,搜索用时 265 毫秒
82.
Wandi Wahyudi Viko Ladelta Leonidas Tsetseris Merfat M. Alsabban Xianrong Guo Emre Yengel Hendrik Faber Begimai Adilbekova Akmaral Seitkhan Abdul-Hamid Emwas Mohammed N. Hedhili Lain-Jong Li Vincent Tung Nikos Hadjichristidis Thomas D. Anthopoulos Jun Ming 《Advanced functional materials》2021,31(23):2101593
Electrolyte additives have been widely used to address critical issues in current metal (ion) battery technologies. While their functions as solid electrolyte interface forming agents are reasonably well-understood, their interactions in the liquid electrolyte environment remain rather elusive. This lack of knowledge represents a significant bottleneck that hinders the development of improved electrolyte systems. Here, the key role of additives in promoting cation (e.g., Li+) desolvation is unraveled. In particular, nitrate anions (NO3−) are found to incorporate into the solvation shells, change the local environment of cations (e.g., Li+) as well as their coordination in the electrolytes. The combination of these effects leads to effective Li+ desolvation and enhanced battery performance. Remarkably, the inexpensive NaNO3 can successfully substitute the widely used LiNO3 offering superior long-term stability of Li+ (de-)intercalation at the graphite anode and suppressed polysulfide shuttle effect at the sulfur cathode, while enhancing the performance of lithium–sulfur full batteries (initial capacity of 1153 mAh g−1 at 0.25C) with Coulombic efficiency of ≈100% over 300 cycles. This work provides important new insights into the unexplored effects of additives and paves the way to developing improved electrolytes for electrochemical energy storage applications. 相似文献
83.
Neural Computing and Applications - The use of games in daily life, especially in education, has been in an incline during the COVID-2019 pandemic. Thus, game-based learning environments have... 相似文献
84.
ABSTRACTWind turbine control is an important task to make the electricity generation secure in terms of energy demand and machine safety. It also yields to control the desired power level and optimized energy because of the assignment of turbine speed. The contactless piezoelectric wind energy harvester (CPWEH) used in this study has three piezoelectric layers located around the shaft with 120 degrees apart and they are buckled by the magnetic force without any physical contact. The superiority of this device is to generate energy for low wind speeds such as 1.5 m/s. However, for high speeds, high total harmonic distortions (THDs) govern the waveforms, thus controlling the turbine speed becomes necessary for optimizing the output power. Encouraged by this, a small low inertia dc generator is coupled with the wind turbine, and the generator terminals are connected to a resistor through a power switch to generate a braking torque that opposes to wind speed direction. By controlling the switch properly, turbine speed is ensured to remain within a certain band, which accordingly prevents the turbine from rotating very fast at damaging wind speeds. Several experiments are performed on the developed CPWEH with/without the presented control scheme which prove the existence of promising performance of our proposal. 相似文献
85.
Murat Özen Myrjam MertensJan Luyten Frans SnijkersHans D’Hondt Pegie Cool 《Ceramics International》2012,38(1):619-625
In this paper, the amorphous barium titanate precursor was prepared by the peroxo-hydroxide method and post-treated by various drying procedures, such as: room temperature drying, room temperature vacuum drying and vacuum drying at 50 °C. The objective in the latter two treatments was to increase the Ti-O-Ba bonds of the precursor. The post-treated precursors were compared with the untreated (i.e., ‘wet’) precursor. Also, a barium titanate precursor was prepared by an alkoxide route. Afterwards, the precursors were hydrothermally treated at 200 °C in a 10 M NaOH solution. Vacuum drying of the precursor seemingly promoted the formation of Ti-O-Ti bonds in the hydrothermal end-product. The low Ba:Ti ratio (0.66) of the alkoxide-route prepared precursor lead to a multi-phase hydrothermal product with BaTiO3 as the main phase. In contrast, phase pure BaTiO3, i.e. without BaCO3 contamination, was obtained for the precursor which was dried at room temperature. Cube-shaped and highly crystalline BaTiO3 particles were observed by electron microscopy for the hydrothermally treated peroxo-hydroxide-route prepared precursor. 相似文献
86.
Yunus Emre Unsal Mustafa Soylak Mustafa Tuzen 《International Journal of Food Science & Technology》2012,47(6):1253-1258
A new and simple solid‐phase extraction method for the determination of trace levels of sunset yellow has been developed on Diaion HP 2MG column system. The adsorbed sunset yellow on the resin was eluted with 3 mL of methanol and determined by UV–Vis spectrophotometry at 484 nm. Various experimental parameters such as pH, amount of sunset yellow, flow rates of sample and eluent solutions, resin amount, sample volumes, etc. were investigated. The influences of some alkali, alkali earth and transition metals on the recoveries of sunset yellow were investigated. The recovery values for sunset yellow were higher than 95%. Preconcentration factor was found as 150. The detection limit (three sigma) of the reagent blank for sunset yellow was 5.2 μg L?1. The relative standard deviations (RSD) of the procedure were found as 3.9%. The validation of the presented procedure was performed by the method of standard addition. The procedure was successfully applied to the determination of trace levels of sunset yellow in powdered beverage and confectionery products. 相似文献
87.
Neural Computing and Applications - 相似文献
88.
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90.
Ali Gökhan Demir Barbara Previtali 《The International Journal of Advanced Manufacturing Technology》2014,75(9-12):1557-1568
Thin sheet anode and cathode materials made in composite structures constitute some of the most important components of a Li-ion battery. These materials are currently cut by punching technology, which shows degrading behaviour as the tool wears out. A viable option for Li-ion battery electrode manufacturing is the use of remote laser cutting. However, the operation requires fulfilling both productivity and quality aspects to substitute the conventional production method. One of the most critical aspects in quality is the clearance width, which is defined as the extent of the exposed middle layer of the sandwich at the laser cut kerf. This work investigates the quality aspects of laser cutting of Li-ion electrodes when a green fibre laser source (λ?=?532 nm, τ?=?1 ns) is used rather than the more traditional infrared (IR) fibre laser source (λ?=?1,064 nm, τ?=?250 ns). The processing conditions were investigated to reveal the technological feasibility zones. Clearance width was studied within the technological feasibility zones for all the material-laser combinations. Results showed that high productivity criterion is met by the IR system, since cutting speed could reach 30 m/min with 54 W average laser power on both anode and cathode. On the other hand, the green laser provided clearance width below 20 μm. In the best case, the clearance on anode could be eliminated with the green laser system. Although the maximum cutting speed was 4.5 m/min, upscaling of green laser power can provide required productivity. 相似文献