Journal articles: 'Coulomb efficiency'

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LAURITSCH, G., and P. G. REINHARD. "AN FFT SOLVER FOR THE COULOMB PROBLEM." International Journal of Modern Physics C 05, no. 01 (February 1994): 65–75. http://dx.doi.org/10.1142/s0129183194000064.

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A solution of the Coulomb problem in Fourier representation is given. The problems with the long-range parts of the Coulomb potential are circumvented by a separate handling of them. This allows the Fourier representation to develop its typical efficiency and robusteness.

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Song, P., P. Kraus, V. Kumar, and P. Dupont. "Analysis of Rigid-Body Dynamic Models for Simulation of Systems With Frictional Contacts." Journal of Applied Mechanics 68, no. 1 (June 16, 2000): 118–28. http://dx.doi.org/10.1115/1.1331060.

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The use of Coulomb’s friction law with the principles of classical rigid-body dynamics introduces mathematical inconsistencies. Specifically, the forward dynamics problem can have no solutions or multiple solutions. In these situations, compliant contact models, while increasing the dimensionality of the state vector, can resolve these problems. The simplicity and efficiency of rigid-body models, however, provide strong motivation for their use during those portions of a simulation when the rigid-body solution is unique and stable. In this paper, we use singular perturbation analysis in conjunction with linear complementarity theory to establish conditions under which the solution predicted by the rigid-body dynamic model is stable. We employ a general model of contact compliance to derive stability criteria for planar mechanical systems. In particular, we show that for cases with one sliding contact, there is always at most one stable solution. Our approach is not directly applicable to transitions between rolling and sliding where the Coulomb friction law is discontinuous. To overcome this difficulty, we introduce a smooth nonlinear friction law, which approximates Coulomb friction. Such a friction model can also increase the efficiency of both rigid-body and compliant contact simulation. Numerical simulations for the different models and comparison with experimental results are also presented.

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Qing-Yun, Chen, Shi Dong-Dong, Zhang Yuan-Jun, and Wang Yun-Hai. "Phenol degradation on novel nickel-antimony doped tin dioxide electrode." Water Science and Technology 62, no. 9 (November 1, 2010): 2090–95. http://dx.doi.org/10.2166/wst.2010.401.

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Nickel and antimony doped tin dioxide is a novel anodic material for its good performance of electrochemical ozone generation and direct electro-catalytic oxidation. Electro-catalytic oxidation of phenol on this novel nickel-antimony doped tin dioxide electrode is presented here. The morphology and composition of the electrode are characterized. The effects of applied current densities on phenol degradation rate, energy consumption and coulomb efficiency are discussed. In 0.1 M sulfuric acid, after 4 h electrolysis with current density of 25 mA cm−1, 90% phenol is removed. And with current density of 20 mA cm−1, the highest energy efficiency of 6.85 g kWh−1 and the highest coulomb efficiency of 6.87 μg C−1 are obtained. The effect of current densities on TOC removal is also discussed.

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Wen, T., G. S. Solt, and D. W. Gao. "Electrical resistance and coulomb efficiency of electrodialysis (ED) apparatus in polarization." Journal of Membrane Science 114, no. 2 (June 1996): 255–62. http://dx.doi.org/10.1016/0376-7388(96)00005-1.

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Yu, Chun Jian, Xiao Diao Huang, Cheng Gang Fang, and Ke Fang Dai. "Research on Damping and Vibration Characteristic of the Large and Precision NC Rotary Table." Advanced Materials Research 97-101 (March 2010): 1216–22. http://dx.doi.org/10.4028/www.scientific.net/amr.97-101.1216.

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According to the current situation of acicular chip and high-frequency chattering of the NC rotary table while gear milling, rigidity and damping performances of the table were analyzed and the damping program of Coulomb friction was bring up. Online test of the gear milling cutting force can be used to establish dynamic model of circumferential vibration of the table with Coulomb friction. Then mechanism of restraining gear cutting chatter by damping of Coulomb friction and acicular chip generating mechanism were exposed. Furthermore, relationship between backlash and rotary rigidity of the table was also analyzed. A kind of floating apparatus with friction damping was designed to optimize circumferential damping of the table by adjusting Coulomb friction force, which reduces the influence of high-frequency chattering on gear milling. As a result, efficiency of gear milling was increased 1.5 times and the noise was reduced from 105dB to 91dB.

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Krasny, Robert, and Lei Wang. "A treecode based on barycentric Hermite interpolation for electrostatic particle interactions." Computational and Mathematical Biophysics 7, no. 1 (December 13, 2019): 73–84. http://dx.doi.org/10.1515/cmb-2019-0006.

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AbstractA particle-cluster treecode based on barycentric Hermite interpolation is presented for fast summation of electrostatic particle interactions in 3D. The interpolation nodes are Chebyshev points of the 2nd kind in each cluster. It is noted that barycentric Hermite interpolation is scale-invariant in a certain sense that promotes the treecode’s efficiency. Numerical results for the Coulomb and screened Coulomb potentials show that the treecode run time scales like O(N log N), where N is the number of particles in the system. The advantage of the barycentric Hermite treecode is demonstrated in comparison with treecodes based on Taylor approximation and barycentric Lagrange interpolation.

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Kerr, Mark J., Andres Cuevas, and Patrick Campbell. "Limiting efficiency of crystalline silicon solar cells due to Coulomb-enhanced Auger recombination." Progress in Photovoltaics: Research and Applications 11, no. 2 (2003): 97–104. http://dx.doi.org/10.1002/pip.464.

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Yang, Bin, Jin Wang, Youyu Zhu, Kemeng Ji, Chengyang Wang, Dianbo Ruan, and Yongyao Xia. "Engineering hard carbon with high initial coulomb efficiency for practical sodium-ion batteries." Journal of Power Sources 492 (April 2021): 229656. http://dx.doi.org/10.1016/j.jpowsour.2021.229656.

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Masuda, Yoshitake, Junji Akimoto, and Kazumi Kato. "Nanoarchitectonics of Acicular Nanocrystal Assembly and Nanosheet Assembly for Lithium-Ion Batteries." Journal of Nanoscience and Nanotechnology 20, no. 5 (May 1, 2020): 3004–12. http://dx.doi.org/10.1166/jnn.2020.17443.

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Nanoarchitectonics of metal oxide nanocrystal electrodes were developed for lithium-ion batteries. The electrodes included copper nanoparticles and doped fluorine. For the acicular nanocrystals, charge–discharge reactions progressed at 1.8 V over 100 cycles at 100 and 10 μA. A 15-mmdiameter battery containing acicular nanocrystals showed capacity, coulomb efficiency, and specific capacity, respectively of 20 μAh, 98%, and ~242 mAh/g at 100 μA and 40 μAh, 99%, and 484 mAh/g at 10 μA. The TiO2/SnO2 electrode consisted of a SnO2 sheet-assembled structure with surface layers of anatase TiO2. The TiO2/SnO2 battery operated at 1.3 (100 cycles) and 1.2 (50 cycles) V at 100 and 10 μA, respectively; its capacity, coulomb efficiency, and specific capacity, respectively were 50 μAh, 98%, and 161 mAh/g at 100 μA and 200 μAh, 97–98%, and 643 mAh/g at 10 μA. The characteristic microstructure, chemical composition, and crystal faces of both materials contributed to battery performance.

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Nikhamkin, M. Sh, S. V. Semenov, G. V. Mekhonoshin, I. V. Semenova, and N. A. Sazhenkov. "Twin Shaft Rotor System Vibration Damping Experimental Investigation." Applied Mechanics and Materials 752-753 (April 2015): 918–21. http://dx.doi.org/10.4028/www.scientific.net/amm.752-753.918.

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The influence of dry friction damping on twin shaft model test rig vibration experimental investigation is presented. Experimental investigation method is devised and tested at the work. Dry and Coulomb friction damper is developed. The efficiency of damping is evaluated quantitatively via rotor shaft vibration displacements amplitude determining.

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11

Li, Fei, Shao Jun Wang, Li Wei, Wei Na Tao, Xue Yang Dong, and Hua Liu. "LiFePO₄/Li Batteries with Mixtures of Carbonate and Ionic Liquid [EMIM]⁺[TFSI]^- as High Properties and Safety Electrolyte." Applied Mechanics and Materials 275-277 (January 2013): 2375–80. http://dx.doi.org/10.4028/www.scientific.net/amm.275-277.2375.

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The electrolyte optimum composition consists of 1mol/L LiTFSI in the [EMIM]+[TFSI]-mixed with EC and DMC in weight ratio of 60:20:20. The LiFePO4/Li cell using 1 mol/L LiTFSI/([EMIM]+[TFSI]-/EC/DMC) as electrolyte show that the first coulomb efficiency was 90% and the first discharge capacity was 168mAh g-1. The 15th reversible capacities were maintain 157mAh g-1at 0.2C. Compared with traditional organic electrolyte and pure IL electrolyte, IL-based mixed electrolyte have good coulomb efficiencies and higher charge and discharge performances. The lithium transference number of IL-based mixed electrolyte at room temperature are 0.59. Thermal stability of IL-based mixed electrolyte higher than traditional organic electrolyte, and show almost non-flammability by the burning tests.

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Winzer, Torben, and Ermin Malić. "Microscopic study of the efficiency of Coulomb- and phonon-induced relaxation channels in graphene." physica status solidi (b) 248, no. 11 (September 21, 2011): 2615–18. http://dx.doi.org/10.1002/pssb.201100048.

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13

Tan Tai, Nguyen Huynh, and Le Van Anh. "A simple weak form for contact problems with Coulomb friction." Vietnam Journal of Mechanics 33, no. 4 (December 12, 2011): 259–82. http://dx.doi.org/10.15625/0866-7136/33/4/259.

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This paper proposes a weak form for the contact problem with Coulomb friction, written as extension of the standard virtual work principle and involving both the displacements and the multipliers defined on the reference contact surface. The mixed relationship is shown to be equivalent to the strong form of the initial/boundary value contact problem, and it can be discretized by means of the finite element method in a simple way. Typical numerical examples are given to assess the efficiency of the formulation in statics and dynamics.

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Mandzyuk, V. I., V. G. Khomenko, V. M. Sachko, I. F. Myronyuk, and V. Z. Barsukov. "The Lithium Power Sources Based on Porous Carbon Material." Фізика і хімія твердого тіла 16, no. 1 (March 15, 2015): 217–20. http://dx.doi.org/10.15330/pcss.16.1.217-220.

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The paper describes the use of porous carbon material (PCM), obtained from plant raw materials as anode of lithium power source (LPS). It is established that the electrochemical parameters of LPS at current density of C/20 are stable over long cycling (over 90 charge/discharge cycles) – discharge capacity remained at 150 mA∙h/g, and Coulomb efficiency exceeds 95%.

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Spyrou, A., H. W. Becker, A. Lagoyannis, S. Harissopulos, and C. Rolfs. "A 4π γ-summing method for cross-section measurements of capture reactions." HNPS Proceedings 15 (January 1, 2020): 111. http://dx.doi.org/10.12681/hnps.2627.

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Capture reaction cross sections at energies far below the Coulomb barrier are of major importance for the understanding of stellar nucleosynthesis. Since the cross sections of the majority of these reactions are very small, the use of high efficiency detectors is essential. In this work, a new method for capture reaction cross section measurements based on a large volume 4π NaI detector is presented.

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Gümüş, Sedat. "On The Computation Of Two-Center Coulomb Integrals Over Slater Type Orbitals Using The Poisson Equation." Zeitschrift für Naturforschung A 60, no. 7 (July 1, 2005): 477–83. http://dx.doi.org/10.1515/zna-2005-0702.

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In this paper, a new analytical formula has been derived for the two-center Coulomb integrals over Slater type orbitals using the Poisson equation. The obtained results from constructed computer program for the presented formula have been compared with the available literature and it is seen that the efficiency of the presented algorithm for a wide range of quantum numbers, orbital exponents and internuclear distances is satisfactory.

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Lee, Wonmi, Byeong Wan Kwon, Mina Jung, Dmytro Serhiichuk, Dirk Henkensmeier, and Yongchai Kwon. "Iron-vanadium redox flow batteries with polybenzimidazole membranes: High coulomb efficiency and low capacity loss." Journal of Power Sources 439 (November 2019): 227079. http://dx.doi.org/10.1016/j.jpowsour.2019.227079.

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Takeuchi, Tomonari, Toshikatsu Kojima, Hiroyuki Kageyama, Hironori Kobayashi, Kei Mitsuhara, Koji Nakanishi, and Toshiaki Ohta. "All‐Solid‐State Lithium‐Sulfur Batteries Using Sulfurized Alcohol Composite Material with Improved Coulomb Efficiency." Energy Technology 7, no. 12 (July 30, 2019): 1900509. http://dx.doi.org/10.1002/ente.201900509.

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19

Liu, Yunjian, Jun Lv, Guangyan Zhu, Yanyong Gao, Sanbin Liu, and Xiaohua Chen. "Improvement of the first coulomb efficiency and rate performance of Li1.5Ni0.25Mn0.75O2.5 with spinel LiNi0.5Mn1.5O4 doping." Ionics 19, no. 10 (January 31, 2013): 1335–40. http://dx.doi.org/10.1007/s11581-013-0859-4.

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20

Mulia, Dipa. "UKURAN TOKO DAN HOMOGENITAS BARANG DAGANGAN PENGARUHNYA TERHADAP DAYA TARIK TOKO TERHADAP KONSUMEN." Jurnal Manajemen 19, no. 3 (February 28, 2017): 426. http://dx.doi.org/10.24912/jm.v19i3.32.

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Munculnya toko toko baru biasanya menimbulkan “pergerakan konsumen” dari satu toko yang sudah ada kepada toko yang baru muncul. Toko toko yang letaknya saling berdekatan saling mempengaruhi satu sama lain dalam memperebutkan konsumen yang sama sehingga dapat dikatakan bahwa kinerja toko secara keseluruhan menjadi tidak efisisien. Model Elektrostatik atau Model Coulomb yang diperkenalkan oleh ahli Fiska abad 18, Charles Augustine de Coulomb dapat digunakan dalam menganalisis pengaruh toko terhadap konsumennya sehingga dapat dibuatkan desain toko agar kinerjanya menjadi efisien. Makalah ini dibuat melalui riset diskriptif dengan menggunakan pendekatan kuantitatif dengan mengambil sampel 5 buah toko dengan ukuran dan jenis yang berbeda. Responden diambil sebanyak 60 orang per toko dengan total responden sebanyak 300 orang. Hasil penelitian menunjukkan bahwa besar ukuran toko dan keragaman produk yang dijual mempengaruhi daya tarik toko terhadap konsumen.Introducing new store to customer usually create the “customer shift” from the existing store to the new one. When the new store is located nearby the existing one, the shifting could not be avoided; it means the efficiency of store is becoming less than before. In order to optimize the efficiency of store the distance between stores should be managed. This paper implements theClassic Model of Electrostatic Forces that also known as Model of Coulomb.The Model was promoted by France Physicist, Charles Augustine de Coulomb, in 18th Century. The attractiveness of store to customer is represented by the electrostatic force on the Model. This paper is a descriptive research with a quantitative approach; the object of research is 5 (five) stores with different types in term of size and product offered. There were 60 qualified respondents selected on each store, in total it was 300 respondents. The result of the research tells that the size of store and the homogeneity of product offered are influencing the attractiveness ofthe store to the customer.

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Yu, Chunjian, Xiaodiao Huang, and Chenggang Fang. "Research on dynamic characteristics of NC rotary table considering leakage factors of its hydrostatic guideway." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 226, no. 11 (February 7, 2012): 2674–85. http://dx.doi.org/10.1177/0954406212437642.

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The rigidity and damping characteristics of a large and heavy NC rotary table have great influence on machining efficiency and the integrated machine’s dynamic accuracy, but test and control methods related to these characteristics are difficult to apply. In the axial direction, the table was supported by a constant current hydrostatic guideway; the guideway’s surface roughness and planeness errors were the main factors contributing to hydraulic oil leakage. Based on the force analysis of a ZT20SW driven by double worm gear pairs, a dynamic model and an electromechanical–hydraulic coupling model in the circumferential direction were established. Simulation and experimental results altogether indicated that the cutting force on the table, leakage characteristics and Coulomb frictional force of the hydrostatic guideway each have great effects on dynamical accuracy. In addition, test methods on the leakage’s equivalent oil film thickness offer a new comprehensive evaluation standard for the hydrostatic guideway’s geometric errors. The hydrostatic guideway’s Coulomb frictional force can be controlled reasonably to improve the table’s dynamic accuracy.

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Xu, Chenglong, Jialei Lu, Zhimiao Zhao, Yinjiang Zhang, and Jiawei Zhang. "Electricity Generation, Salt and Nitrogen Removal and Microbial Community in Aircathode Microbial Desalination Cell for Saline-Alkaline Soil-Washing Water Treatment." Water 12, no. 8 (August 12, 2020): 2257. http://dx.doi.org/10.3390/w12082257.

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An aircathode microbial desalination cell (AMDC) was successfully started by inoculating anaerobic sludge into the anode of a microbial desalination cell and then used to study the effects of salinity on performance of AMDC and effect of treatment of coastal saline-alkaline soil-washing water. The results showed that the desalination cycle and rate gradually shorten, but salt removal gradually increased when the salinity was decreased, and the highest salt removal was 98.00 ± 0.12% at a salinity of 5 g/L. COD removal efficiency was increased with the extension of operation cycle and largest removal efficiency difference was not significant, but the average coulomb efficiency had significant differences under the condition of each salinity. This indicates that salinity conditions have significant influence on salt removal and coulomb efficiency under the combined action of osmotic pressure, electric field action, running time and microbial activity, etc. On the contrary, COD removal effect has no significant differences under the condition of inoculation of the same substrate in the anode chamber. The salt removal reached 99.13 ± 2.1% when the AMDC experiment ended under the condition of washing water of coastal saline-alkaline soil was inserted in the desalination chamber. Under the action of osmotic pressure, ion migration, nitrification and denitrification, NH4+-N and NO3−-N in the washing water of the desalination chamber were removed, and this indicates that the microbial desalination cell can be used to treatment the washing water of coastal saline-alkaline soil. The microbial community and function of the anode electrode biofilm and desalination chamber were analyzed through high-throughput sequencing, and the power generation characteristics, organics degradation and migration and transformation pathways of nitrogen of the aircathode microbial desalination cell were further explained.

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Priestley, F. D., I. De Looze, and M. J. Barlow. "The efficiency of grain growth in the diffuse interstellar medium." Monthly Notices of the Royal Astronomical Society 502, no. 2 (January 15, 2021): 2438–45. http://dx.doi.org/10.1093/mnras/stab122.

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ABSTRACT Grain growth by accretion of gas-phase metals is a common assumption in models of dust evolution, but in dense gas, where the time-scale is short enough for accretion to be effective, material is accreted in the form of ice mantles rather than adding to the refractory grain mass. It has been suggested that negatively charged small grains in the diffuse interstellar medium (ISM) can accrete efficiently due to the Coulomb attraction of positively-charged ions, avoiding this issue. We show that this inevitably results in the growth of the small-grain radii until they become positively charged, at which point further growth is effectively halted. The resulting gas-phase depletions under diffuse ISM conditions are significantly overestimated when a constant grain size distribution is assumed. While observed depletions can be reproduced by changing the initial size distribution or assuming highly efficient grain shattering, both options result in unrealistic levels of far-ultraviolet extinction. We suggest that the observed elemental depletions in the diffuse ISM are better explained by higher initial depletions, combined with inefficient dust destruction by supernovae at moderate ($n_{\rm H}\sim 30 \, {\rm cm}^{-3}$) densities, rather than by higher accretion efficiences.

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MACHTOUB, GHADA H. "NEW APPROACH TO THREE-BODY COULOMB PROBLEM WITH NONZERO TOTAL ANGULAR MOMENTUM." International Journal of Modern Physics C 12, no. 06 (July 2001): 835–50. http://dx.doi.org/10.1142/s0129183101002000.

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Our approach aims at a general formalism for the quantum description of the three-body Coulomb systems. We seek the exact solutions of 6D Schrödinger equation. For this, we propose a new algorithm for the case of nonzero total angular momentum, taking into account the overall rotation of the system, which is affected indirectly by the Coriolis coupling. We construct a special set of hyperspherical harmonics, which provide much more flexibility in choosing the best basis for the needs of this particular physical problem. The robustness, efficiency, and accuracy of the adopted algorithm are studied in detail. We apply this method to the computation of the nonrelativistic energy levels of the exotic helium [Formula: see text].

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Lee, Jeong, Jun-Mo Kim, Junsin Yi, and Chung-Yuen Won. "Battery Management System Algorithm for Energy Storage Systems Considering Battery Efficiency." Electronics 10, no. 15 (August 2, 2021): 1859. http://dx.doi.org/10.3390/electronics10151859.

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Aging increases the internal resistance of a battery and reduces its capacity; therefore, energy storage systems (ESSs) require a battery management system (BMS) algorithm that can manage the state of the battery. This paper proposes a battery efficiency calculation formula to manage the battery state. The proposed battery efficiency calculation formula uses the charging time, charging current, and battery capacity. An algorithm that can accurately determine the battery state is proposed by applying the proposed state of charge (SoC) and state of health (SoH) calculations. To reduce the initial error of the Coulomb counting method (CCM), the SoC can be calculated accurately by applying the battery efficiency to the open circuit voltage (OCV). During the charging and discharging process, the internal resistance of a battery increase and the constant current (CC) charging time decrease. The SoH can be predicted from the CC charging time of the battery and the battery efficiency, as proposed in this paper. Furthermore, a safe system is implemented during charging and discharging by applying a fault diagnosis algorithm to reduce the battery efficiency. The validity of the proposed BMS algorithm is demonstrated by applying it in a 3-kW ESS.

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Han, Jia Jun, Jin Ning Cheng, Feng Wen Pan, Xin Kui Liu, and Fang Zhang. "Effect of Synthesis Process of Polyaniline for the Zn-PANi Secondary Batteries." Advanced Materials Research 608-609 (December 2012): 1342–46. http://dx.doi.org/10.4028/www.scientific.net/amr.608-609.1342.

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The facters of molar ratio of aniline and ammonium persulfate ,aniline concentration, concentration of HCl , carbon species and different additives was studied on the yield and conductivity of polyaniline, also the coulomb efficiency and the cycle life of Zinc-PANi secondary battery. Results show that: the molar ratio of aniline and ammonium persulfate is 1:0.9, aniline concentration 0.12mol/L and the wooden actived carbon is 35% of the weight of aniline, the best value of conductivity and capacity are respectively 2.27S/cm and 121.5mAh/g.

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Huang, He, Li-Shi Luo, Rui Li, Jie Chen, and He Zhang. "Improve the efficiency of the Cartesian tensor based fast multipole method for Coulomb interaction using the traces." Journal of Computational Physics 371 (October 2018): 122–36. http://dx.doi.org/10.1016/j.jcp.2018.05.028.

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Morozovskiy, Pavel, Anna Babanina, Kristina Ziiaeva, and Sergey Shulzhenko. "Optimization of parameters of the bearing structures of deep excavations with minimization of environmental impacts." E3S Web of Conferences 110 (2019): 01002. http://dx.doi.org/10.1051/e3sconf/201911001002.

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The aim of the project is optimizing the parameters of deep foundation pits in order to improve their technical efficiency and economic feasibility, and development of an optimization algorithm. The analysis is carried out using the program complex PLAXIS 2D 2011. The article considers a model of the foundation pits to a depth of 5-20 m with various settings of attachment. To study the work of the soil body, the Mohr- Coulomb model is used as the simplest and strengthening soil with a small strain as the most reliable.

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Yu, Fei, Bo Rong Wu, Hong Liang Xu, and Feng Wu. "Synthesis, Characterization and Electrochemistry of Cathode Material Li [Li_0.2Mn_0.54Ni_0.13Co_0.13]O₂ Nanofibers Prepared by Electrospinning for Lithium Ion Batteries." Advanced Materials Research 860-863 (December 2013): 928–32. http://dx.doi.org/10.4028/www.scientific.net/amr.860-863.928.

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Nanofibers of Li [Li0.2Mn0.54Ni0.13Co0.13]O2with high crystallinity were easily synthesized by electrospinning. Scanning electron microscopy (SEM) showed that precursor wires were glossy, and the diameters of oxide calcined at 800°C were 50-200 nm. And X-ray diffraction (XRD) exhibited perfect crystal structure. The electrochemical properties of materials with the specific morphology were significantly improved. The first charge/discharge capacity was around 309.3 and 270.2 mAh·g-1at 25 mA·g-1, and the first coulomb efficiency (87.4%) represented a good efficiency for Li2MnO3-type electrodes. After 20 cycles, discharge capacity was over 200 mAh·g-1at 25 mA·g-1, and capacity retention was 79.8% at 250 mA·g-1.Owing to its simplicity and applicability, the electrospinning method is an promising method to fabricate high performance Li [Li0.2Mn0.54Ni0.13Co0.13]O2materials for lithium ion batteries.

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Zhu, Yiting, Xuejun Zhu, Teruyuki Izumi, and Masashi Kanesaka. "Optimal Velocity Function Minimizing Dissipated Energy Considering All Friction in a Position Control System." Journal of Robotics and Mechatronics 19, no. 1 (February 20, 2007): 97–105. http://dx.doi.org/10.20965/jrm.2007.p0097.

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In order to help reduce global warming, the amount of dissipated energy of machines should be decreased. The present paper discusses optimal current and velocity functions that minimize the dissipated energy in a servo system with friction of all types. The Coulomb friction of a gear in the servo system is represented by the efficiency of the gear and is assumed to be proportional to the absolute value of the output torque of the motor. Even if the system is nonlinear due to Coulomb friction, an analytical optimal function can be solved by introducing a zero crossing time <I>tc</I>, when the input torque of the gear changes from positive to negative. The influence of the viscous friction upon the optimal zero crossing time <I>tc*</I> is examined by simulations. The energy dissipated with the optimal velocity function is compared to the energy dissipated with a conventional trapezoidal velocity function. The results of the simulations and the experiment indicate that the optimal velocity function can greatly reduce the amount of energy dissipated when the moment of inertia is large.

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Last, Isidore, Shlomo Ron, Andreas Heidenreich, and Joshua Jortner. "Coulomb explosion of nanodroplets drives the conversion of laser energy to nuclear energy." High Power Laser Science and Engineering 1, no. 2 (June 20, 2013): 69–73. http://dx.doi.org/10.1017/hpl.2013.10.

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AbstractTheoretical–computational studies of table-top laser-driven nuclear fusion of high-energy (up to 15 MeV) deuterons with ${}^{7} \mathrm{Li} $, ${}^{6} \mathrm{Li} $, and D nuclei demonstrate the attainment of high fusion yields within a source–target reaction design. This constitutes a source of Coulomb-exploding deuterium nanodroplets driven by an ultraintense femtosecond near-infrared laser and a solid hollow cylindrical target containing the second element. The source–target reaction design attains the highest table-top fusion efficiencies (up to $4\times 1{0}^{9} ~{\mathrm{J} }^{- 1} $ per laser pulse) obtained to date. The highest conversion efficiency of laser energy to nuclear energy ($1{0}^{- 2} $–$1{0}^{- 3} )$ for table-top DD fusion attained in the source–target design is comparable to that for DT fusion currently accomplished for ‘big science’ inertial fusion setups.

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Kaplan, A. E. "Coulomb cluster explosion boosted by an electrical pulse—neutron source, diagnostic tool, and test of nuclear fusion efficiency." Journal of Physics B: Atomic, Molecular and Optical Physics 52, no. 4 (January 22, 2019): 04LT01. http://dx.doi.org/10.1088/1361-6455/aafa56.

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Mehta, R., G. Bissinger, and J. M. Joyce. "Reduced error in σKX via nuclear-Coulomb excited absolute detector efficiency normalization for targets with Z = 29−79." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 56-57 (May 1991): 30–32. http://dx.doi.org/10.1016/0168-583x(91)95963-e.

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Lai, Yiming, Lei Wan, and Baoguo Wang. "PVDF/Graphene Composite Nanoporous Membranes for Vanadium Flow Batteries." Membranes 9, no. 7 (July 19, 2019): 89. http://dx.doi.org/10.3390/membranes9070089.

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The development of chemically stable and high conductive membranes is one of the most important issues to improve the performance of vanadium flow batteries (VFBs). Herein, poly(vinylidene fluoride) (PVDF)/graphene composite nanoporous membranes were easily fabricated by manipulating crystallization processes. The graphene was used to enhance membrane selectivity and conductivity. In the nanoscale channels of the membranes, the graphene nanosheets reduced the apertures among the crystal grains, thus restraining vanadium ions crossover due to the size exclusion effect. Moreover, the oxygen groups on the graphene improved the surface hydrophilicity and formed hydrogen bonds with the PVDF polymer chains, which facilitated the proton transport. The composite membranes, with a 0.15 wt % graphene loading, showed a selectivity of 38.2 and conductivity of 37.1 mS/cm. The single cell exhibited a coulomb efficiency of 94.7%, a voltage efficiency of 88.5%, and an energy efficiency of 83.8%, which was 13% higher than that of the pristine PVDF membranes. The composite membranes showed excellent stability during 100 charge-discharge cycles. All these results indicate that the PVDF/graphene composite membrane is a promising candidate for VFB applications.

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Kuo, Ting-Jung. "Development of a Comprehensive Model for the Coulombic Efficiency and Capacity Fade of LiFePO4 Batteries under Different Aging Conditions." Applied Sciences 9, no. 21 (October 28, 2019): 4572. http://dx.doi.org/10.3390/app9214572.

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In this paper, a comprehensive model for LiFePO4 batteries is proposed to ensure high efficiency and safe operation. The proposed model has a direct correlation between its parameters and the electrochemical principles to estimate the state of charge (SoC) and the remaining capacity of the LiFePO4 battery. This model was based on a modified Thévenin circuit, Butler–Volmer kinetics, the Arrhenius equation, Peukert’s law, and a back propagation neural network (BPNN), which can be divided into two parts. The first part can be represented by the dual exponential terms, responsive to the Coulomb efficiency; the second part can be described by the BPNN, estimating the remaining capacity. The model successfully estimates the SoC of the batteries that were tested with an error of 1.55%. The results suggest that the model is able to accurately estimate the SoC and the remaining capacity in various environments (discharging C rates and temperatures).

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Wang, S. J., X. M. Zong, B. He, and K. X. Kang. "Research on Prediction Model of Conical Pick Cutting Force Based on Coulomb-Mohr Criterion." MATEC Web of Conferences 319 (2020): 04001. http://dx.doi.org/10.1051/matecconf/202031904001.

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Cutting force is one of the most important influence factors that affect the efficiency and service life of the conical pick. In order to accurately calculate the cutting force, through theoretical analysis and experimental research, a cutting force model consisted of the basic fracture parameters of rock, geometric parameters and installation parameters of pick is proposed based on the coulomb-mohr criterion, and the calculation model is corrected by whole cutting experimental data, and validated the corrected model by orthogonal test, the result show that the error of the cutting force model is about 10%, which meets the requirements of engineering data. At the same time, significant analysis on the cutting force is obtained by range method, cutting depth h > semi-tip angle β > cutting angle α.

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Yuan, Li, Yun Zhang, Wen Jing Liu, Fu Wang, and Chao Lu. "Influences of Re-Sintering on the Structure and Electrochemical Performance of LiNi_1/3Co_1/3Mn_1/3O₂." Advanced Materials Research 669 (March 2013): 355–59. http://dx.doi.org/10.4028/www.scientific.net/amr.669.355.

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The influences of re-sintering on the structure and electrochemical performance of LiNi1/3Co1/3Mn1/3O2 were researched in this paper. The synthesized materials were characterized and tested by means of X-ray diffraction (XRD) and electrochemical measurements respectively. It was found that the re-sintered samples with better well-ordered layered structure, more perfect crystallization and more complete crystal structure will be formed with increasing temperature. Moreover, reasonable re-sintering time was required. The materials re-sintered at 860°C for 2h exhibited the best electrochemical performance, including high initial discharge capacity of 150.6 mAh•g-1 and coulomb efficiency of 84% at 0.2C rate.

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Wang, Kesheng, Yijia Lu, Jia Cheng, and Linhong Ji. "Prediction of residual clamping force for Coulomb type and Johnsen–Rahbek type of bipolar electrostatic chucks." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 1 (February 12, 2018): 302–12. http://dx.doi.org/10.1177/0954406218756938.

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As a key component in semiconductor manufacturing equipment, electrostatic chuck is conventionally divided into Coulomb type and J–R type depending on the generating mechanism of clamping force. After supply voltage is cut off, residual clamping force usually remains and becomes a serious issue for production efficiency and process reliability. Hence, it is significant to propose a general prediction model and reveal changing laws of residual force with time for both types. This paper establishes an equivalent circuit model for a bipolar electrostatic chuck containing distributed embosses on dielectric layer surface, and deduces a unified form of mathematical expression describing decaying force, which can cover the two types. The obtained equations can also predict steady force in working state. Furthermore, an experimental method for measuring clamping force and de-clamping time is presented. The results indicate relative deviations tend to decrease as voltages rise. It is found that prediction precision for J–R type is lower than that for Coulomb type. Main reasons are explained and relevant mechanisms are discussed. Overall, the calculations coincide with the measurements within an acceptable error range. The comparisons suggest the theoretical model is effective for simulating the characteristics of residual clamping force for both types of electrostatic chucks.

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Bratman, Vladimir, Yuri Lurie, Yuliya Oparina, and Andrey Savilov. "Capabilities of Terahertz Cyclotron and Undulator Radiation from Short Ultrarelativistic Electron Bunches." Instruments 3, no. 4 (October 11, 2019): 55. http://dx.doi.org/10.3390/instruments3040055.

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Mechanisms of coherent spontaneous cyclotron and undulator radiations of short dense bunches, in which electrons move along the same stationary helical trajectories, but have different dynamic properties, have been compared in detail. The results are based on the simplest 1D model in the form of a plane consisting of uniformly distributed synchronously moving and in-phase emitting particles, as well as numerical 3D codes developed to study the dynamics of bunches in waveguides taking into account the effects of the radiation and spatial charge fields. For cyclotron radiation under group synchronism conditions, the Coulomb expansion of a bunch occurs along the surface of a constant wave phase with the formation of an effectively radiating coherent structure. A significantly higher radiation frequency, but with a lower efficiency, can be obtained in the regime of simultaneous excitation of high-frequency (autoresonant) and low-frequency waves; in the field of the latter, stabilization of the bunch phase size can be achieved. Such a two-wave generation is much more efficient when the bunches radiate in the combined undulator and strong guiding magnetic fields under conditions of the negative mass instability, when both the Coulomb interaction of the particles and the radiation field stabilize the longitudinal size of the bunch.

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Lasemi, Niusha, Günther Rupprechter, Gerhard Liedl, and Dominik Eder. "Near-Infrared Femtosecond Laser Ablation of Au-Coated Ni: Effect of Organic Fluids and Water on Crater Morphology, Ablation Efficiency and Hydrodynamic Properties of NiAu Nanoparticles." Materials 14, no. 19 (September 24, 2021): 5544. http://dx.doi.org/10.3390/ma14195544.

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Scanning electron microscopy (SEM) and profilometry of the crater morphology and ablation efficiency upon femtosecond laser ablation of Au-coated Ni targets in various fluids revealed a pronounced dependence on the ablation medium. For ethanol, a sufficient ablation efficiency was obtained, whereas for 2-butanol a higher efficiency indicated stronger laser–target interaction. Hierarchical features in the crater periphery pointed to asymmetrical energy deposition or a residual effect of the Coulomb-explosion-initiating ablation. Significant beam deviation in 2-butanol caused maximum multiple scattering at the crater bottom. The highest values of microstrain and increased grain size, obtained from Williamson–Hall plots, indicated the superposition of mechanical stress, defect formation and propagation of fatigue cracks in the crater circumference. For n-hexane, deposition of frozen droplets in the outer crater region suggested a femtosecond-laser-induced phase explosion. A maximum ablation depth occurred in water, likely due to its high cooling efficiency. Grazing incidence micro X-ray diffraction (GIXRD) of the used target showed residual carbon and partial surface oxidation. The produced nanoparticle colloids were examined by multiangle dynamic light scattering (DLS), employing larger scattering angles for higher sensitivity toward smaller nanoparticles. The smallest nanoparticles were obtained in 2-butanol and ethanol. In n-hexane, floating carbon flakes originated from femtosecond-laser-induced solvent decomposition.

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Tan, Zhi, Zhenhua Sun, Haihua Wang, Qi Guo, and Dangsheng Su. "Fabrication of porous Sn–C composites with high initial coulomb efficiency and good cyclic performance for lithium ion batteries." Journal of Materials Chemistry A 1, no. 33 (2013): 9462. http://dx.doi.org/10.1039/c3ta10524e.

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Tabbara, Mazen, and Gebran Karam. "Parametric Investigation of the Effects of Localization and Slenderness on the Stress–Strain Response and Confinement Efficiency in FRP-Wrapped Concrete Cylinders." Applied Sciences 10, no. 10 (May 15, 2020): 3432. http://dx.doi.org/10.3390/app10103432.

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In order to improve the efficiency of fiber reinforced plastics (FRP) confinement as a method to repair and strengthen concrete structures, a parametric analysis was carried out to investigate the effects of cylinder slenderness and the stiffness of the confinement on the localization pattern, the stress–strain response and the effectiveness of the confinement. FRP-wrapped concrete cylinders under axial compression were modeled in a high-resolution finite element model. Concrete was modeled as a Mohr–Coulomb material. The bi-linear stress–strain structural responses concur with published experimental data. Localization along discrete shear planes results in a failure mechanism that causes non-uniform hoop stresses in the FRP wrap due to the movement of solid wedges in the mechanism. A characteristic length for localization was identified and found in agreement with published experimental observations. The confinement efficiency shows a clear dependence on the confinement level and a weak dependence on slenderness above the characteristic length. A simple mechanistic model is proposed for the second branch of the bi-linear stress–strain response curve. The results of this study can be used to estimate the confinement efficiency factor and refine the design recommendations of Equation 12.1 of ACI 440.2R17.

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Wu, Shou Min, Lie Sheng Wei, and Gang Huang. "Research on the Minimum Rolled Thickness of Strip Steel in Cold Tandem Rolling." Key Engineering Materials 622-623 (September 2014): 993–99. http://dx.doi.org/10.4028/www.scientific.net/kem.622-623.993.

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In consideration of the zone between rolls and deformed area where friction at roll-sheet interface is lower than predetermined value of Coulomb friction in rolling process of ultrathin strip steel, fully integrated with equipment and process features of cold tandem mills, after a large number of field experiments and theoretical studies, on the basis of the improvement of ultrathin strip steel rolling force model, with the allowable rolling pressure and production efficiency as constraint condition, a new calculated theory about the minimum rolled thickness was put forward. What’s more, the theory will be used in the productive practice of 1220 five-rack cold tandem mills of China. The technique has the value to be further popularized.

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Qiu, Lei, Zi Qiang Shao, Ming Shan Yang, Wen Jun Wang, Fei Jun Wang, You Qi Li, and Jing Chen. "Study on the Synthesis CMCAB Electro Spinning Carbon-Coated LiFePO₄ Anode Materials." Advanced Materials Research 634-638 (January 2013): 2613–16. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.2613.

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LiFePO4 was spinning with cellulose derivatives by electrostatic spinning for the first time. Processing conditions were adjusted to the solution concentration of 15%, an applied voltage of 25KV, the quality of mixed solvent with 4:1, and then about 0.1μm nano-fibrous non-woven fabrics can be obtained. FTIR showed that the CMCAB was synthesized successfully. Coulomb efficiency of electrode materials before and after the modification was maintained at about 100%, specific capacity of the battery in 2C of discharge rate, it was the first time that discharge specific capacity had increased from the unmodified 147.6 mAh.g-1 to the modified 160.6 mAh.g-1Superscript text. After 200 weeks' cycle, the capacity loss decreased from 11.38% to 5.11%.

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Li, Shi You, Yang Yu Zhao, Wei Zhao, and Xiao Ling Cui. "Effect of Lithium Bis(oxalate)Borate-Based Electrolyte on the Performance of LiNi_0.5Mn_1.5O₄ for High Voltage Lithium-Ion Batteries." Key Engineering Materials 519 (July 2012): 156–59. http://dx.doi.org/10.4028/www.scientific.net/kem.519.156.

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LiNi0.5Mn1.5O4 is a promising 5 V class anode material for high power applications, however, before applying in lithium-ion batteries, it is necessary to find more appropriate electrolyte systems to exert the perfect electrochemical performance of LiNi0.5Mn1.5O4. In this paper, the electrochemical performances of LiBOB-propylene carbonate (PC)/dimethyl carbonate (DMC) electrolyte are investigated. It shows high oxidation potentials (>5.5 V) and satisfactory conductivities, When used in LiNi0.5Mn1.5O4/Li cells, compared to the cell with the electrolyte system of LiPF6-ethylene carbonate (EC)/dimethyl carbonate (DMC) electrolyte, LiBOB-PC/DMC electrolyte exhibit several advantages, such as more stable cycle performance, higher discharge voltage plateau (>4.64 V), higher coulomb efficiency, and higher mean voltage (4.55 V).

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Sercel, Peter C., Andrew Shabaev, and Alexander L. Efros. "Symmetry Breaking Induced Activation of Nanocrystal Optical Transitions." MRS Advances 3, no. 14 (2018): 711–16. http://dx.doi.org/10.1557/adv.2018.19.

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ABSTRACTWe have analysed the effect of symmetry breaking on the optical properties of semiconductor nanocrystals due to doping by charged impurities. Using doped CdSe nanocrystals as an example, we show the effects of a Coulomb center on the exciton fine-structure and optical selection rules using symmetry theory and then quantify the effect of symmetry breaking on the exciton fine structure, modelling the charged center using a multipole expansion. The model shows that the presence of a Coulomb center breaks the nanocrystal symmetry and affects its optical properties through mixing and shifting of the hole spin and parity sublevels. This symmetry breaking, particularly for positively charged centers, shortens the radiative lifetime of CdSe nanocrystals even at room temperature, in qualitative agreement with the increase in PL efficiency observed in CdSe nanocrystals doped with positive Ag charge centers [A. Sahu et.al., Nano Lett. 12, 2587, (2012)]. The effect of the charged center on the photoluminescence and the absorption spectra is shown, with and without the presence of compensating charges on the nanocrystal surface. While spectra of individual nanocrystals are expected to shift and broaden with the introduction of a charged center, configuration averaging and inhomogeneous broadening are shown to wash out these effects. The presence of compensating charges at the NC surface also serves to stabilize the band edge transition energies relative to NCs with no charge centers.

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47

Ma. "Design and Implementation of a Hybrid Real-Time State of Charge Estimation Scheme for Battery Energy Storage Systems." Processes 8, no. 1 (December 18, 2019): 2. http://dx.doi.org/10.3390/pr8010002.

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In order to maximize the operating flexibility and optimize the system performance of a battery energy storage system (BESS), developing a reliable real-time estimation method for the state of charge (SOC) of a BESS is one of the crucial tasks. In practice, the accuracy of real-time SOC detection can be interfered with by various factors, such as battery’s intrinsic nonlinearities, working current, temperature, and aging level, etc. Considering the feasibility in practical applications, this paper proposes a hybrid real-time SOC estimation scheme for BESSs based on an adaptive network-based fuzzy inference system (ANFIS) and Coulomb counting method, where a commercially available lead-acid battery-based BESS is used as the research target. The ANFIS allows effective learning of the nonlinear characteristics in charging and discharging processes of a battery. In addition, the Coulomb counting method with an efficiency adjusting mechanism is simultaneously used in the proposed scheme to provide a reference SOC for checking the system reliability. The proposed estimating scheme was first simulated in a Matlab software environment and then implemented with an experimental hardware setup, where an industrial-grade digital control system using DS1104 as the control kernel and dSPACE Real-Time Interface (RTI) interface were used. Results from both simulation and experimental tests verify the feasibility and effectiveness of the proposed hybrid SOC estimation algorithm.

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Kim, Min-Young, Byeong-Su Kang, Sang-Jun Park, Jinsub Lim, Youngsun Hong, Jong-Hun Han, and Ho-Sung Kim. "Energy Efficiency Improvement of Vanadium Redox Flow Battery by Integrating Electrode and Bipolar Plate." Journal of Electrochemical Science and Technology 12, no. 3 (August 31, 2021): 330–38. http://dx.doi.org/10.33961/jecst.2021.00017.

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An integral electrode-bipolar plate assembly, which is composed of electrode, conductive adhesive film (CAF) and bipolar plate, has been developed and evaluated for application with a vanadium redox flow battery (VRB) to decrease contact resistance between electrode and bipolar plate. The CAF, made of EVA (ethylene-vinyl-acetate) material with carbon black or CNT (Carbon Nano Tube), is applied between the electrode and the bipolar plate to enable an integral assembly by adhesion. In order to evaluate the integral assembly of VRB by adhesive film, the resistivity of integral assembly and the performance of single cell were investigated. Thus, it was verified that the integral assembly is applicable to redox flow battery. Through resistance and contact resistance of bare EVA and CAF films on bipolar plate were changed. Among the adhesive films, CAF film coated with carbon black showed the lowest value in through resistance, and CAF film coated with CNT showed the lowest value in contact resistance, respectively. The efficiency of VRB single cell was improved by applying CAF films coated with carbon black and CNT, resulting in the reduced overvoltage in charging process. Therefore, the energy efficiency of both CAF films, about 84%, were improved than that of blank cell, about 79.5 % under current density at 40 mA cm−2. The energy efficiency of the two cells were similar, but carbon black coated CAF improved the coulomb efficiency and CNT coated CAF improved the voltage efficiency, respectively.

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Liu, Bai Xi. "Dynamic Parameters Estimation Based on Set Inversion and Interval Analysis Algorithm." Advanced Materials Research 591-593 (November 2012): 1954–57. http://dx.doi.org/10.4028/www.scientific.net/amr.591-593.1954.

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In the paper, an approach, based on bounded-error estimation via interval analysis, is presented to identify viscous damping coefficient and Coulomb friction coefficient of such-rod pumping system of directional well. The approach assumes the error of colleted output data of suck-rod pumping system is bounded. Hence, the problem of parameter estimation can be viewed as that of set inversion, which will be effectively solved via interval analysis. The main advantage of the proposed method in comparison with the traditional estimation methods is that, as it is global, it bypasses the problem of initialization. Moreover, the method avoids amount error due to transformation of measurement output data. An identification example is given to show the correctness and efficiency of the proposed method.

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Gao, Pan, Zhihui Liu, Danda Shi, Xuehua Fu, and Keliang Yan. "Mitigation Effect of Perforation Drilling on the Sliding Risk during Spudcan Installation Close to Footprints." Journal of Marine Science and Engineering 8, no. 2 (February 14, 2020): 118. http://dx.doi.org/10.3390/jmse8020118.

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Perforation drilling is a promising technique to mitigate the sliding risk of jack-up units installed around footprints. Based on the coupled Eulerian–Lagrangian (CEL) method, a 1/2 finite element model, including a rigid Lagrangian spudcan and a Eulerian soil part, was established, and the contact interface was modelled with the Coulomb friction model. Validated against an indoor perforation test, the model was adopted to investigate the mitigation mechanism and effects of the borehole diameter, number, depth, and the drilling range. The simulations reveal that the mitigation efficiency increases with the borehole diameter, number, and depth. However, it shows little improvement if the borehole depth increases beyond double footprint depth. The semi-drilling at the outer side of the footprint is a little more effective than the full-drilling at both the inner and outer sides of the footprint. The present work emphasizes the effects of perforation drilling parameters on the mitigation efficiency, which are of great significance to guide the engineering practice and guarantee the safe operation of the jack-up reinstallation close to existing footprints.

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Journal articles on the topic 'Coulomb efficiency'

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