An analytical expression of ampere’s force between two current rings in a compensated torsion balance is deduced here,the properties and stability of this force are discussed.The result of numerical estimation for ty...An analytical expression of ampere’s force between two current rings in a compensated torsion balance is deduced here,the properties and stability of this force are discussed.The result of numerical estimation for typical experimental parameters shows that the uncertainties of the force are smaller than 1×10^(-4) orders,which is very important for precise measurement of gravitational constant G.展开更多
Ionic liquid electrospray(ILE) in an atmospheric environment is often accompanied by the gas discharge phenomenon. It interferes with the normal operation of the electrospray and the measurement of experimental parame...Ionic liquid electrospray(ILE) in an atmospheric environment is often accompanied by the gas discharge phenomenon. It interferes with the normal operation of the electrospray and the measurement of experimental parameters. In this study, electrospray experiments were conducted on the ionic liquid EMI-BF4. The observations revealed that the operating modes of the ionic liquid depend on the voltage polarity at high voltages. Additionally, a correspondence between the operating mode of ILE and the current signal in the circuit was established. The shape of the liquid cone formed at the needle tip bore a striking resemblance to the plume of corona discharge, suggesting that the motion trajectory of electrons influenced the curvature of the liquid cone. Steamer theory provided a clear explanation for the change in curvature as the voltage increased.展开更多
Optical whispering gallery mode （WGM） microresonators have attracted great attention due to their remarkable proper- ties such as extremely high quality factor, small mode volume, tight confinement of modes, and str...Optical whispering gallery mode （WGM） microresonators have attracted great attention due to their remarkable proper- ties such as extremely high quality factor, small mode volume, tight confinement of modes, and strong evanescent field. All these properties of WGM microresonators have ensured their great potentials for applications, such as physical sen- sors, bio/chemical sensors and microlasers. In this mini-review, the key parameters and coupling conditions of WGM microresonators are firstly introduced. The geometries of WGM optical microcavities are presented based on their fabri- cation methods. This is followed by the discussion on the state-of-the-art applications of WGM microresonators in sen- sors and microlasers.展开更多
We repeated Saxl’s electrically charged pendulum experiment with an accuracy about one order higher.We found.no anomalous period change reported by him.Further experiment research shows that his result could be expla...We repeated Saxl’s electrically charged pendulum experiment with an accuracy about one order higher.We found.no anomalous period change reported by him.Further experiment research shows that his result could be explained if there were the affection of a capacitance between the pendulum disk and other part of the apparatus in his experiment.展开更多
We have carried out a high precision torsion balance experiment in searching for abnormally large coherent scattering cross sections between a sapphire crystal and solar-neutrino.According to the hypothesis and the ex...We have carried out a high precision torsion balance experiment in searching for abnormally large coherent scattering cross sections between a sapphire crystal and solar-neutrino.According to the hypothesis and the experimental results presented by J.Weber,a diurnal effect,which was 60 times larger than the noise level,should he observed obviously,but no significant diurnal effects were found at the level of 8.1 x 10^(-8) dyn in our experiment.展开更多
文摘An analytical expression of ampere’s force between two current rings in a compensated torsion balance is deduced here,the properties and stability of this force are discussed.The result of numerical estimation for typical experimental parameters shows that the uncertainties of the force are smaller than 1×10^(-4) orders,which is very important for precise measurement of gravitational constant G.
基金supported by the National Key Research and Development Program of China(No.2020YFC2201004)National Natural Science Foundation of China(No.12172110)。
文摘Ionic liquid electrospray(ILE) in an atmospheric environment is often accompanied by the gas discharge phenomenon. It interferes with the normal operation of the electrospray and the measurement of experimental parameters. In this study, electrospray experiments were conducted on the ionic liquid EMI-BF4. The observations revealed that the operating modes of the ionic liquid depend on the voltage polarity at high voltages. Additionally, a correspondence between the operating mode of ILE and the current signal in the circuit was established. The shape of the liquid cone formed at the needle tip bore a striking resemblance to the plume of corona discharge, suggesting that the motion trajectory of electrons influenced the curvature of the liquid cone. Steamer theory provided a clear explanation for the change in curvature as the voltage increased.
基金This work is partially supported by National Natural Science Foundation of China （11774102）, the Scientific Research Funds and Promotion Program for Young and Middle-aged Teacher in Science ＆ Technology Research of Huaqiao University （ZQN-YXS04, 17BS412）, Open Fund of IPOC （BUPT）, National Research Foundation Singapore （NRF） （NRF-CRP13-2014-05）, European Union＇s Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement （No. 798916） and Singapore Ministry of Education Academic Research Fund Tier 1 （RG89/16）.
文摘Optical whispering gallery mode （WGM） microresonators have attracted great attention due to their remarkable proper- ties such as extremely high quality factor, small mode volume, tight confinement of modes, and strong evanescent field. All these properties of WGM microresonators have ensured their great potentials for applications, such as physical sen- sors, bio/chemical sensors and microlasers. In this mini-review, the key parameters and coupling conditions of WGM microresonators are firstly introduced. The geometries of WGM optical microcavities are presented based on their fabri- cation methods. This is followed by the discussion on the state-of-the-art applications of WGM microresonators in sen- sors and microlasers.
基金Supported by the National Natural Science Foundation of China.
文摘We repeated Saxl’s electrically charged pendulum experiment with an accuracy about one order higher.We found.no anomalous period change reported by him.Further experiment research shows that his result could be explained if there were the affection of a capacitance between the pendulum disk and other part of the apparatus in his experiment.
基金Supported by the National Natural Science Foundation of Chinathe HUO Yingdong Educational Foundation.
文摘We have carried out a high precision torsion balance experiment in searching for abnormally large coherent scattering cross sections between a sapphire crystal and solar-neutrino.According to the hypothesis and the experimental results presented by J.Weber,a diurnal effect,which was 60 times larger than the noise level,should he observed obviously,but no significant diurnal effects were found at the level of 8.1 x 10^(-8) dyn in our experiment.
