High field asymmetric wave ion mobility spectrometry （FAIMS） is a powerful tool to detect and characterize gas-phase ions, while the unsolvable partial differential equation of ions moving in ion drift tube poses a ...High field asymmetric wave ion mobility spectrometry （FAIMS） is a powerful tool to detect and characterize gas-phase ions, while the unsolvable partial differential equation of ions moving in ion drift tube poses a big challenge to FAIMS spectral peak analysis. In this work, a universal and effective model of FAIMS spectral peak profile has been proposed by introducing ion trajectory and loss height. With this model, the influence of the structure of ion drift tube, dispersion voltages, compensation voltages, and carrier gas flow rate on the FAIMS spectral peak characteristics like peak shape, full width at half maximum and peak height is analyzed and discussed. The results show that the influence of different factors on the FAIMS spectral peak profile can be qualitatively described by the model which agrees with the experimental data.展开更多
A simple model for a set of integrate-and-fire neurons based on the weighted network is introduced. By considering the neurobiological phenomenon in brain development and the difference of the synaptic strength, we co...A simple model for a set of integrate-and-fire neurons based on the weighted network is introduced. By considering the neurobiological phenomenon in brain development and the difference of the synaptic strength, we construct weighted networks develop with link additions and followed by selective edge removal. The network exhibits the small-world and scale-free properties with high network efficiency. The model displays an avalanche activity on a power-law distribution. We investigate the effect of selective edge removal and the neuron refractory period on the self-organized criticality of the system.展开更多
Climate change brings unprecedented challenges to both the international community as well as international law. For example, extreme weather conditions might cause States to disappear and force its populations to mig...Climate change brings unprecedented challenges to both the international community as well as international law. For example, extreme weather conditions might cause States to disappear and force its populations to migrate. These phenomenon creates new challenges for current international law. First, under current legal frameworks, there is no provision regarding the disappearance of a State due to climate change. Second, for people who are forced to migrate due to climate change whether caused internally or internationally, current legal framework is also unclear to whether they could be classified as refugees and to what extent should they be protected. Despite these uncertainties, people of these endangered States cannot be left to fend themselves simply because there is a legal vacuum. This paper proposes a way forward for to meet this challenge and urge the international community to use this opportunity to refine the currently existing legal regime in order to solve the various challenges posed by climate change.展开更多
基金This work was supported by the National Natural Science Foundation of China （No.60871037 andNo.61004133） and the Innovation and Technology Fund of Hefei Institutes of Physical Science.
文摘High field asymmetric wave ion mobility spectrometry （FAIMS） is a powerful tool to detect and characterize gas-phase ions, while the unsolvable partial differential equation of ions moving in ion drift tube poses a big challenge to FAIMS spectral peak analysis. In this work, a universal and effective model of FAIMS spectral peak profile has been proposed by introducing ion trajectory and loss height. With this model, the influence of the structure of ion drift tube, dispersion voltages, compensation voltages, and carrier gas flow rate on the FAIMS spectral peak characteristics like peak shape, full width at half maximum and peak height is analyzed and discussed. The results show that the influence of different factors on the FAIMS spectral peak profile can be qualitatively described by the model which agrees with the experimental data.
基金Supported by National Natural Science Foundation of China under Grant No.10675060the Doctoral Foundation of Ministry of Education of China under Grant No.2002055009
文摘A simple model for a set of integrate-and-fire neurons based on the weighted network is introduced. By considering the neurobiological phenomenon in brain development and the difference of the synaptic strength, we construct weighted networks develop with link additions and followed by selective edge removal. The network exhibits the small-world and scale-free properties with high network efficiency. The model displays an avalanche activity on a power-law distribution. We investigate the effect of selective edge removal and the neuron refractory period on the self-organized criticality of the system.
文摘Climate change brings unprecedented challenges to both the international community as well as international law. For example, extreme weather conditions might cause States to disappear and force its populations to migrate. These phenomenon creates new challenges for current international law. First, under current legal frameworks, there is no provision regarding the disappearance of a State due to climate change. Second, for people who are forced to migrate due to climate change whether caused internally or internationally, current legal framework is also unclear to whether they could be classified as refugees and to what extent should they be protected. Despite these uncertainties, people of these endangered States cannot be left to fend themselves simply because there is a legal vacuum. This paper proposes a way forward for to meet this challenge and urge the international community to use this opportunity to refine the currently existing legal regime in order to solve the various challenges posed by climate change.
