The Experts below are selected from a list of 40299 Experts worldwide ranked by ideXlab platform
Shi Xue Dou - One of the best experts on this subject based on the ideXlab platform.
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Achieving High-Performance Room-Temperature Sodium-Sulfur Batteries With S@Interconnected Mesoporous Carbon Hollow Nanospheres.
Journal of the American Chemical Society, 2016Co-Authors: Yunxiao Wang, Jianping Yang, Weihong Lai, Shulei Chou, Hua-kun Liu, Dongyuan Zhao, Shi Xue DouAbstract:Despite the high theoretical capacity of the sodium–sulfur battery, its application is seriously restrained by the challenges due to its low sulfur electroactivity and accelerated shuttle effect, which lead to low accessible capacity and Fast Decay. Herein, an elaborate carbon framework, interconnected mesoporous hollow carbon nanospheres, is reported as an effective sulfur host to achieve excellent electrochemical performance. Based on in situ synchrotron X-ray diffraction, the mechanism of the room temperature Na/S battery is proposed to be reversible reactions between S8 and Na2S4, corresponding to a theoretical capacity of 418 mAh g–1. The cell is capable of achieving high capacity retention of ∼88.8% over 200 cycles, and superior rate capability with reversible capacity of ∼390 and 127 mAh g–1 at 0.1 and 5 A g–1, respectively.
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Achieving High-Performance Room-Temperature Sodium–Sulfur Batteries With S@Interconnected Mesoporous Carbon Hollow Nanospheres
2016Co-Authors: Yunxiao Wang, Jianping Yang, Weihong Lai, Shulei Chou, Hua-kun Liu, Dongyuan Zhao, Shi Xue DouAbstract:Despite the high theoretical capacity of the sodium–sulfur battery, its application is seriously restrained by the challenges due to its low sulfur electroactivity and accelerated shuttle effect, which lead to low accessible capacity and Fast Decay. Herein, an elaborate carbon framework, interconnected mesoporous hollow carbon nanospheres, is reported as an effective sulfur host to achieve excellent electrochemical performance. Based on in situ synchrotron X-ray diffraction, the mechanism of the room temperature Na/S battery is proposed to be reversible reactions between S8 and Na2S4, corresponding to a theoretical capacity of 418 mAh g–1. The cell is capable of achieving high capacity retention of ∼88.8% over 200 cycles, and superior rate capability with reversible capacity of ∼390 and 127 mAh g–1 at 0.1 and 5 A g–1, respectively
Olga Kocharovskaya - One of the best experts on this subject based on the ideXlab platform.
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slow gamma photon with a doublet structure time delay via a transition from destructive to constructive interference of collectively scattered radiation with the incoming photon
Physical Review A, 2009Co-Authors: R.n. Shakhmuratov, Joseph Odeurs, Farit G. Vagizov, Olga KocharovskayaAbstract:Single gamma photon propagation in a dense absorptive medium with two widely spaced resonances is experimentally studied. After an initial Fast Decay, a revival of the photon amplitude in the form of a bump, exceeding the probability amplitude of the incident photon, is observed. The irradiation time of this bump delays approximately by the lifetime of the excited nuclei in the absorber. This effect is explained by the interference of the incoming radiation with the collectively scattered radiation, the phase of which is modulated with the frequency of the doublet splitting. Initially, the destructive interference changes to a constructive one, distinguishing the storage and retrieval stages of the photon propagation in a dense medium, i.e., the collective absorption and collective re-emission processes.
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slow γ photon with a doublet structure time delay via a transition from destructive to constructive interference of collectively scattered radiation with the incoming photon
Physical Review A, 2009Co-Authors: R.n. Shakhmuratov, Joseph Odeurs, Farit G. Vagizov, Olga KocharovskayaAbstract:Single $\ensuremath{\gamma}$ photon propagation in a dense absorptive medium with two widely spaced resonances is experimentally studied. After an initial Fast Decay, a revival of the photon amplitude in the form of a bump, exceeding the probability amplitude of the incident photon, is observed. The irradiation time of this bump delays approximately by the lifetime of the excited nuclei in the absorber. This effect is explained by the interference of the incoming radiation with the collectively scattered radiation, the phase of which is modulated with the frequency of the doublet splitting. Initially, the destructive interference changes to a constructive one, distinguishing the storage and retrieval stages of the photon propagation in a dense medium, i.e., the collective absorption and collective re-emission processes.
Yunxiao Wang - One of the best experts on this subject based on the ideXlab platform.
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Achieving High-Performance Room-Temperature Sodium-Sulfur Batteries With S@Interconnected Mesoporous Carbon Hollow Nanospheres.
Journal of the American Chemical Society, 2016Co-Authors: Yunxiao Wang, Jianping Yang, Weihong Lai, Shulei Chou, Hua-kun Liu, Dongyuan Zhao, Shi Xue DouAbstract:Despite the high theoretical capacity of the sodium–sulfur battery, its application is seriously restrained by the challenges due to its low sulfur electroactivity and accelerated shuttle effect, which lead to low accessible capacity and Fast Decay. Herein, an elaborate carbon framework, interconnected mesoporous hollow carbon nanospheres, is reported as an effective sulfur host to achieve excellent electrochemical performance. Based on in situ synchrotron X-ray diffraction, the mechanism of the room temperature Na/S battery is proposed to be reversible reactions between S8 and Na2S4, corresponding to a theoretical capacity of 418 mAh g–1. The cell is capable of achieving high capacity retention of ∼88.8% over 200 cycles, and superior rate capability with reversible capacity of ∼390 and 127 mAh g–1 at 0.1 and 5 A g–1, respectively.
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Achieving High-Performance Room-Temperature Sodium–Sulfur Batteries With S@Interconnected Mesoporous Carbon Hollow Nanospheres
2016Co-Authors: Yunxiao Wang, Jianping Yang, Weihong Lai, Shulei Chou, Hua-kun Liu, Dongyuan Zhao, Shi Xue DouAbstract:Despite the high theoretical capacity of the sodium–sulfur battery, its application is seriously restrained by the challenges due to its low sulfur electroactivity and accelerated shuttle effect, which lead to low accessible capacity and Fast Decay. Herein, an elaborate carbon framework, interconnected mesoporous hollow carbon nanospheres, is reported as an effective sulfur host to achieve excellent electrochemical performance. Based on in situ synchrotron X-ray diffraction, the mechanism of the room temperature Na/S battery is proposed to be reversible reactions between S8 and Na2S4, corresponding to a theoretical capacity of 418 mAh g–1. The cell is capable of achieving high capacity retention of ∼88.8% over 200 cycles, and superior rate capability with reversible capacity of ∼390 and 127 mAh g–1 at 0.1 and 5 A g–1, respectively
John E. Lisman - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Fast Decay of CaMKII FRET Sensor Signal in Spines after LTP Induction Is Not Due to Its
2016Co-Authors: Nikolai Otmakhov, Shaurav Regmi, John E. LismanAbstract:Because CaMKII is the critical Ca2+ sensor that triggers long-term potentiation (LTP), un-derstanding its activation and deactivation is important. A major advance has been the development of a FRET indicator of the conformational state of CaMKII called Camui. Experiments using Camui have demonstrated that the open (active) conformation increases during LTP induction and then Decays in tens of seconds, with the major Fast component Decaying with a time-constant of ~ 6 sec (tau1). Because this Decay is Faster if autopho-sphorylation of T286 is prevented (the autophosphorylation prolongs activity by making the enzyme active even after Ca2+ falls), it seemed likely that the Fast Decay is due to the T286 dephosphorylation. To test this interpretation, we studied the effect of phosphatase inhibi-tors on the single-spine Camui signal evoked by two-photon glutamate uncaging. We applied inhibitors of PP1 and PP2A, two phosphatases that are present at synapses and that have been shown to dephosphorylate CaMKII in vitro. The inhibitors increased the basal Camui activation state, indicating their effectiveness in cells. However, in no case did we find that tau1 was prolonged, contrary to what would be expected if the Decay was phos-phatase-dependent. This could either mean that Decay was due to some unknown phos-phatase or that the Decay was not due to dephosphorylation. To distinguish between these possibilities, we expressed pseudo-phosphorylated Camui (T286D) (plus additional muta-tions [T/A] that prevented inhibitory 305/306 phosphorylation). This form had an elevated basal activation state, but was further activated during glutamate uncaging; importantly the activation state Decayed with tau1 nearly the same as that of WT Camui. Therefore, the data strongly indicate that tau1 is not due to T286 dephosphorylation. We conclude that, although Camui is an excellent tool for observing CaMKII signaling, further experimentation is needed to determine how CaMKII is turned off by its dephosphorylation
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Fast Decay of CaMKII FRET Sensor Signal in Spines after LTP Induction Is Not Due to Its Dephosphorylation.
PloS one, 2015Co-Authors: Nikolai Otmakhov, Shaurav Regmi, John E. LismanAbstract:Because CaMKII is the critical Ca2+ sensor that triggers long-term potentiation (LTP), understanding its activation and deactivation is important. A major advance has been the development of a FRET indicator of the conformational state of CaMKII called Camui. Experiments using Camui have demonstrated that the open (active) conformation increases during LTP induction and then Decays in tens of seconds, with the major Fast component Decaying with a time-constant of ~ 6 sec (tau1). Because this Decay is Faster if autophosphorylation of T286 is prevented (the autophosphorylation prolongs activity by making the enzyme active even after Ca2+ falls), it seemed likely that the Fast Decay is due to the T286 dephosphorylation. To test this interpretation, we studied the effect of phosphatase inhibitors on the single-spine Camui signal evoked by two-photon glutamate uncaging. We applied inhibitors of PP1 and PP2A, two phosphatases that are present at synapses and that have been shown to dephosphorylate CaMKII in vitro. The inhibitors increased the basal Camui activation state, indicating their effectiveness in cells. However, in no case did we find that tau1 was prolonged, contrary to what would be expected if the Decay was phosphatase-dependent. This could either mean that Decay was due to some unknown phosphatase or that the Decay was not due to dephosphorylation. To distinguish between these possibilities, we expressed pseudo-phosphorylated Camui (T286D) (plus additional mutations [T/A] that prevented inhibitory 305/306 phosphorylation). This form had an elevated basal activation state, but was further activated during glutamate uncaging; importantly the activation state Decayed with tau1 nearly the same as that of WT Camui. Therefore, the data strongly indicate that tau1 is not due to T286 dephosphorylation. We conclude that, although Camui is an excellent tool for observing CaMKII signaling, further experimentation is needed to determine how CaMKII is turned off by its dephosphorylation.
R.n. Shakhmuratov - One of the best experts on this subject based on the ideXlab platform.
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slow gamma photon with a doublet structure time delay via a transition from destructive to constructive interference of collectively scattered radiation with the incoming photon
Physical Review A, 2009Co-Authors: R.n. Shakhmuratov, Joseph Odeurs, Farit G. Vagizov, Olga KocharovskayaAbstract:Single gamma photon propagation in a dense absorptive medium with two widely spaced resonances is experimentally studied. After an initial Fast Decay, a revival of the photon amplitude in the form of a bump, exceeding the probability amplitude of the incident photon, is observed. The irradiation time of this bump delays approximately by the lifetime of the excited nuclei in the absorber. This effect is explained by the interference of the incoming radiation with the collectively scattered radiation, the phase of which is modulated with the frequency of the doublet splitting. Initially, the destructive interference changes to a constructive one, distinguishing the storage and retrieval stages of the photon propagation in a dense medium, i.e., the collective absorption and collective re-emission processes.
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slow γ photon with a doublet structure time delay via a transition from destructive to constructive interference of collectively scattered radiation with the incoming photon
Physical Review A, 2009Co-Authors: R.n. Shakhmuratov, Joseph Odeurs, Farit G. Vagizov, Olga KocharovskayaAbstract:Single $\ensuremath{\gamma}$ photon propagation in a dense absorptive medium with two widely spaced resonances is experimentally studied. After an initial Fast Decay, a revival of the photon amplitude in the form of a bump, exceeding the probability amplitude of the incident photon, is observed. The irradiation time of this bump delays approximately by the lifetime of the excited nuclei in the absorber. This effect is explained by the interference of the incoming radiation with the collectively scattered radiation, the phase of which is modulated with the frequency of the doublet splitting. Initially, the destructive interference changes to a constructive one, distinguishing the storage and retrieval stages of the photon propagation in a dense medium, i.e., the collective absorption and collective re-emission processes.
