SnO_(2)is used as electrode material with excellent properties,but it has some disadvantages such as slow reaction kinetics,low inherent conductivity and complex preparation process.Here,SnO_(2)@carbon nanotubes(SnO_(...SnO_(2)is used as electrode material with excellent properties,but it has some disadvantages such as slow reaction kinetics,low inherent conductivity and complex preparation process.Here,SnO_(2)@carbon nanotubes(SnO_(2)@CNTs)is synthesized through an efficient method of one-pot alternating current electrochemical dispersion.By using heat treatment at 400℃,the SnO_(2)@CNTs-400 composite material with abundant mesoporous structure is obtained,while the crystal particles are grown,and a strong bonding effect is formed with CNTs via powerful Sn-O-C bond.Benefiting from the introduction of high electrical conductivity CNTs and outstanding structural characteristics,as prepared composite material(SnO_(2)@CNTs-400)exhibit enhanced diffusion dynamics,lithium-ion transmission rate and structural steadiness.The specific capacity of SnO_(2)@CNTs and SnO_(2)@CNTs-400 as anodes for lithium-ion batteries can reach 690.2 mA·h/g and 836.5 mA·h/g,respectively,after 100 cycles at 0.5 A/g.The abundant chemical bonds and porous structure can be formed in composite via alternating current synthesis method,which takes significant in improving electrochemical properties.展开更多
To study the alternating current （AC） impedance properties of Ag/AgC1 electrocardiograph （ECG） electrodes, the electrode pair was gel-to-gel connected, and then the electrical potential was recorded after a safe s...To study the alternating current （AC） impedance properties of Ag/AgC1 electrocardiograph （ECG） electrodes, the electrode pair was gel-to-gel connected, and then the electrical potential was recorded after a safe stimulating current passes through the electrode pair, so the AC impedance data of ECG electrodes were obtained. Varying the frequency and value of stimulating current, the detailed comparison and analysis of AC impedance properties of the electrodes were performed, and the stability was further characterized by using the continuous measurement within 24 h. The experimental results show that the AC impedance values of electrodes decreased, and then slightly increased with the increase of frequency of stimulating current. The minimum AC impedance value was obtained when the frequency was changed to 10 kHz. When the stimulating current increased, the AC impedance values of electrodes showed a slight decrease, but did not change significantly. Besides, the continuous measurement results show that the impedance value presented a significant increase in the initial 30 min, and then was stabilized in the following measuring process.展开更多
Alternating current electrical dynamometer is a common device to measure the torque of engines, such as the gasoline engine. In order to solve the problems such as high cost, high energy consumption and complicated me...Alternating current electrical dynamometer is a common device to measure the torque of engines, such as the gasoline engine. In order to solve the problems such as high cost, high energy consumption and complicated measurement system which exists in the direct measurement on the torque of alternating current electrical dynamometer, copper loss and iron loss are taken as two key factors and a soft-sensing model on the torque of alternating current electrical dynamometer is established using the fuzzy least square support vector machine (FLS-SVM). Then, the FLS-SVM parameters such as penalty factor and kernel parameter are optimized by adaptive genetic algorithm, torque soft-sensing is investigated in the alternating current electrical dynamometer, as well as the energy feedback efficiency and energy consumption during the measurement phase of a gasoline engine loading continual test is obtained. The results show that the minimum soft-sensing error of torque is about 0.0018, and it fluctuates within a range from -0.3 to 0.3 N·m. FLS-SVM soft-sensing method can increase by 1.6% power generation feedback compared with direct measurement, and it can save 500 kJ fuel consumption in the gasoline engine loading continual test. Therefore, the estimation accuracy of the soft measurement model on the torque of alternating current electrical dynamometer including copper loss and iron loss is high and this indirect measurement method can be feasible to reduce production cost of the alternating current electrical dynamometer and energy consumption during the torque measurement phase of a gasoline engine, replacing the direct method of torque measurement.展开更多
基金Project(2023JЛ10041)supported by the Distinguished Young Scholar Fund Project of Hunan Province Natural Science Foundation,ChinaProject(22A0114)supported by the Hunan Provincial Education Office Foundation of China+2 种基金Projects(GX-ZD20211004,GX-ZD20221007)supported by the Science and Technology Program of Xiangtan,ChinaProject(R24-5979269037)supported by the RSC Research Fund Grout,EnglandProject(S202310530037X)supported by the National College Students Innovative Experimental Program Funding Project,China。
文摘SnO_(2)is used as electrode material with excellent properties,but it has some disadvantages such as slow reaction kinetics,low inherent conductivity and complex preparation process.Here,SnO_(2)@carbon nanotubes(SnO_(2)@CNTs)is synthesized through an efficient method of one-pot alternating current electrochemical dispersion.By using heat treatment at 400℃,the SnO_(2)@CNTs-400 composite material with abundant mesoporous structure is obtained,while the crystal particles are grown,and a strong bonding effect is formed with CNTs via powerful Sn-O-C bond.Benefiting from the introduction of high electrical conductivity CNTs and outstanding structural characteristics,as prepared composite material(SnO_(2)@CNTs-400)exhibit enhanced diffusion dynamics,lithium-ion transmission rate and structural steadiness.The specific capacity of SnO_(2)@CNTs and SnO_(2)@CNTs-400 as anodes for lithium-ion batteries can reach 690.2 mA·h/g and 836.5 mA·h/g,respectively,after 100 cycles at 0.5 A/g.The abundant chemical bonds and porous structure can be formed in composite via alternating current synthesis method,which takes significant in improving electrochemical properties.
基金Project(111gpy06) supported by Fundamental Research Funds for the Central Universities,ChinaProject(101055807) supported by the Innovative Experiment Plan for College Students of Sun Yat-sen University,ChinaProject(KF201115) supported by the Opening Fund of Laboratory Sun Yat-sen University,China
文摘To study the alternating current （AC） impedance properties of Ag/AgC1 electrocardiograph （ECG） electrodes, the electrode pair was gel-to-gel connected, and then the electrical potential was recorded after a safe stimulating current passes through the electrode pair, so the AC impedance data of ECG electrodes were obtained. Varying the frequency and value of stimulating current, the detailed comparison and analysis of AC impedance properties of the electrodes were performed, and the stability was further characterized by using the continuous measurement within 24 h. The experimental results show that the AC impedance values of electrodes decreased, and then slightly increased with the increase of frequency of stimulating current. The minimum AC impedance value was obtained when the frequency was changed to 10 kHz. When the stimulating current increased, the AC impedance values of electrodes showed a slight decrease, but did not change significantly. Besides, the continuous measurement results show that the impedance value presented a significant increase in the initial 30 min, and then was stabilized in the following measuring process.
基金Project(11772126) supported by the National Natural Science Foundation of China
文摘Alternating current electrical dynamometer is a common device to measure the torque of engines, such as the gasoline engine. In order to solve the problems such as high cost, high energy consumption and complicated measurement system which exists in the direct measurement on the torque of alternating current electrical dynamometer, copper loss and iron loss are taken as two key factors and a soft-sensing model on the torque of alternating current electrical dynamometer is established using the fuzzy least square support vector machine (FLS-SVM). Then, the FLS-SVM parameters such as penalty factor and kernel parameter are optimized by adaptive genetic algorithm, torque soft-sensing is investigated in the alternating current electrical dynamometer, as well as the energy feedback efficiency and energy consumption during the measurement phase of a gasoline engine loading continual test is obtained. The results show that the minimum soft-sensing error of torque is about 0.0018, and it fluctuates within a range from -0.3 to 0.3 N·m. FLS-SVM soft-sensing method can increase by 1.6% power generation feedback compared with direct measurement, and it can save 500 kJ fuel consumption in the gasoline engine loading continual test. Therefore, the estimation accuracy of the soft measurement model on the torque of alternating current electrical dynamometer including copper loss and iron loss is high and this indirect measurement method can be feasible to reduce production cost of the alternating current electrical dynamometer and energy consumption during the torque measurement phase of a gasoline engine, replacing the direct method of torque measurement.
