Conductive polyanilines are synthesized by doping with inorganic and organic acids, namely Hydrochloric acid (HCl) and ±10-camphor sulfonic acid (CSA). The direct current (DC) conductivities (σDC) are found to b...Conductive polyanilines are synthesized by doping with inorganic and organic acids, namely Hydrochloric acid (HCl) and ±10-camphor sulfonic acid (CSA). The direct current (DC) conductivities (σDC) are found to be about 9.5 ′ 10-8, 1.8, and 95.8 S/cm for PANI base, PANI(HCl) and PANI(CSA), respectively. σDC is measured down to a temperature of ~100 K and the apparent change in the activation energies are found to be 98.16, 74.40, and 57.24 meV for PANI base, HCl, and CSA dopings respectively. σDC is less temperature dependent near room temperature, further decrease in temperature the σDC is strongly dependent. Upon the inspection of AC conductivities (σAC) versus frequency curves, it can be inferred that the conduction process is noticeably influenced upon doping and within the dopants. σAC has shown classical plateau (DC-AC crossover) region, nonetheless shifted crossover frequency (critical frequency) upon doping is rather interesting. Critical frequencies (wc) are obtained from universal power-law for all samples. The variation in the dielectric properties can be attributed to the dopant incorporation. In material characterization, successful doping is corroborated by FTIR, UV-vis spectroscopy and slight influence upon doping can also be seen in thermal properties. Intense photoluminescence (PL) peaks at 322.5, 581.4 and 644.2 nm are observed. PANI(CSA) exhibited highest peak intensity followed by PANI(HCl) and PANI base.展开更多
To measure the void fraction online in oil-gas pipeline, an improved electrical capacitance tomography (ECT) system has been designed. The capacitance sensor with new structure has twelve internal electrodes and overc...To measure the void fraction online in oil-gas pipeline, an improved electrical capacitance tomography (ECT) system has been designed. The capacitance sensor with new structure has twelve internal electrodes and overcomes the influence of the pipe wall. The data collection system is improved by using high performance IC (integrated circuit). Static tests of bubble flow, stratified flow and annular flow regime are carried out. Measurements are taken on bubble flow, stratified flow and slug flow. Results show that the new ECT system performs well on void fraction measurement of bubble flow and stratified flow, but the error of measurement for slug flow is more than 10%.展开更多
There are many reports of devices and fuel additives being able to enhance the performance of automobiles and other forms of transportation that rely upon the combustion of gasoline or diesel fuels. The claims extend ...There are many reports of devices and fuel additives being able to enhance the performance of automobiles and other forms of transportation that rely upon the combustion of gasoline or diesel fuels. The claims extend from increased mileage and power to significant reductions in toxic exhaust emissions of carbon monoxide and unburnt hydrocarbons. Progress towards more widespread applications of means of improving fuel efficiency has been impeded by the lack of a coherent explanation of the mechanism of action. Fuel combustion allows for the conversion of much of the available chemical energy in volatile hydrocarbons to mechanical energy, which moves the pistons within an engine. It is proposed that the amount of chemical energy in hydrocarbons can be increased by the absorption of an environmental force termed KELEA (kinetic energy limiting electrostatic attraction). In addition to providing greater mechanical energy with relatively less heat output, the combustion of KELEA activated fuels proceeds further with less toxic emissions of carbon monoxide and unburnt hydrocarbons from incomplete combustion. KELEA activation of fuels should become standard practice in the transportation industry, with potential additional benefits in slowing the rate of global warming.展开更多
Bismuth telluride(Bi_(2)Te_(3))has attracted much attention in the field of thermoelectrics since it is one kind of commercial room-temperature thermoelectric material.Herein three kinds of Bi_(2)Te_(3) thermoelectric...Bismuth telluride(Bi_(2)Te_(3))has attracted much attention in the field of thermoelectrics since it is one kind of commercial room-temperature thermoelectric material.Herein three kinds of Bi_(2)Te_(3) thermoelectric fibers with internal tensile stress are fabricated utilizing an optical fiber template method.The effects of internal stress on the microstructure and the electrical transportation of Bi_(2)Te_(3) thermoelectric fibers are investigated.The Bi_(2)Te_(3) cores in the fibers are highly crystalline and possess a tensile nanosheet structure with preferential orientation as evidenced by X-ray diffraction and Raman studies.Tensile stress can enhance electrical properties of the fibers.And a paper cup generator covered with 20 pieces of optimized fibers provides a μW-level output power.It is inferred that tensile stress tuning can be an effective tool for the material optimization of thermoelectric performance.展开更多
文摘Conductive polyanilines are synthesized by doping with inorganic and organic acids, namely Hydrochloric acid (HCl) and ±10-camphor sulfonic acid (CSA). The direct current (DC) conductivities (σDC) are found to be about 9.5 ′ 10-8, 1.8, and 95.8 S/cm for PANI base, PANI(HCl) and PANI(CSA), respectively. σDC is measured down to a temperature of ~100 K and the apparent change in the activation energies are found to be 98.16, 74.40, and 57.24 meV for PANI base, HCl, and CSA dopings respectively. σDC is less temperature dependent near room temperature, further decrease in temperature the σDC is strongly dependent. Upon the inspection of AC conductivities (σAC) versus frequency curves, it can be inferred that the conduction process is noticeably influenced upon doping and within the dopants. σAC has shown classical plateau (DC-AC crossover) region, nonetheless shifted crossover frequency (critical frequency) upon doping is rather interesting. Critical frequencies (wc) are obtained from universal power-law for all samples. The variation in the dielectric properties can be attributed to the dopant incorporation. In material characterization, successful doping is corroborated by FTIR, UV-vis spectroscopy and slight influence upon doping can also be seen in thermal properties. Intense photoluminescence (PL) peaks at 322.5, 581.4 and 644.2 nm are observed. PANI(CSA) exhibited highest peak intensity followed by PANI(HCl) and PANI base.
基金the National High Technology Research and Development Program of China (863 Program) (No. 2002AA616050).
文摘To measure the void fraction online in oil-gas pipeline, an improved electrical capacitance tomography (ECT) system has been designed. The capacitance sensor with new structure has twelve internal electrodes and overcomes the influence of the pipe wall. The data collection system is improved by using high performance IC (integrated circuit). Static tests of bubble flow, stratified flow and annular flow regime are carried out. Measurements are taken on bubble flow, stratified flow and slug flow. Results show that the new ECT system performs well on void fraction measurement of bubble flow and stratified flow, but the error of measurement for slug flow is more than 10%.
基金the National Natural Science Foundation of China(60371040)and The Foundation of Science and Technology Commis-sion of Shanghai Municipality(03JC14076)
文摘There are many reports of devices and fuel additives being able to enhance the performance of automobiles and other forms of transportation that rely upon the combustion of gasoline or diesel fuels. The claims extend from increased mileage and power to significant reductions in toxic exhaust emissions of carbon monoxide and unburnt hydrocarbons. Progress towards more widespread applications of means of improving fuel efficiency has been impeded by the lack of a coherent explanation of the mechanism of action. Fuel combustion allows for the conversion of much of the available chemical energy in volatile hydrocarbons to mechanical energy, which moves the pistons within an engine. It is proposed that the amount of chemical energy in hydrocarbons can be increased by the absorption of an environmental force termed KELEA (kinetic energy limiting electrostatic attraction). In addition to providing greater mechanical energy with relatively less heat output, the combustion of KELEA activated fuels proceeds further with less toxic emissions of carbon monoxide and unburnt hydrocarbons from incomplete combustion. KELEA activation of fuels should become standard practice in the transportation industry, with potential additional benefits in slowing the rate of global warming.
基金supported by Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2017BT01X137)National Key Research and Development Program of China(2016YFB0402204)+2 种基金China Postdoctoral Science Foundation(2018M640777)Fundamental Research Funds for Central Universities(D2160590)National Natural Science Foundation of China(U1601205).
文摘Bismuth telluride(Bi_(2)Te_(3))has attracted much attention in the field of thermoelectrics since it is one kind of commercial room-temperature thermoelectric material.Herein three kinds of Bi_(2)Te_(3) thermoelectric fibers with internal tensile stress are fabricated utilizing an optical fiber template method.The effects of internal stress on the microstructure and the electrical transportation of Bi_(2)Te_(3) thermoelectric fibers are investigated.The Bi_(2)Te_(3) cores in the fibers are highly crystalline and possess a tensile nanosheet structure with preferential orientation as evidenced by X-ray diffraction and Raman studies.Tensile stress can enhance electrical properties of the fibers.And a paper cup generator covered with 20 pieces of optimized fibers provides a μW-level output power.It is inferred that tensile stress tuning can be an effective tool for the material optimization of thermoelectric performance.
