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The interaction between KIF21A and KANK1 regulates dendritic morphology and synapse plasticity in neurons
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作者 Shi-Yan Sun Lingyun Nie +5 位作者 Jing Zhang Xue Fang Hongmei Luo Chuanhai Fu Zhiyi Wei Ai-Hui Tang 《Neural Regeneration Research》 SCIE CAS 2025年第1期209-223,共15页
Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory.Kinesin-4 KIF21A helps organize the microtubule-actin network at th... Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory.Kinesin-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1;however,whether KIF21A modulates dendritic structure and function in neurons remains unknown.In this study,we found that KIF21A was distributed in a subset of dendritic spines,and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative spines.Furthermore,the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic plasticity.Knockdown of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching,and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1,but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and talin1.Knocking down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals’cognitive abilities.Taken together,our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function. 展开更多
关键词 ACTIN CYTOSKELETON dendrite KANK1 KIF21A MICROTUBULE spine morphology SPINE synaptic plasticity talin1
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Emergent topological ordered phase for the Ising-XY model revealed by cluster-updating Monte Carlo method
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作者 马赫阳 张万舟 +2 位作者 田彦婷 丁成祥 邓友金 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期386-400,共15页
The two-component cold atom systems with anisotropic hopping amplitudes can be phenomenologically described by a two-dimensional Ising-XY coupled model with spatial anisotropy.At low temperatures,theoretical predictio... The two-component cold atom systems with anisotropic hopping amplitudes can be phenomenologically described by a two-dimensional Ising-XY coupled model with spatial anisotropy.At low temperatures,theoretical predictions[Phys.Rev.A 72053604(2005)]and[arXiv:0706.1609]indicate the existence of a topological ordered phase characterized by Ising and XY disorder but with 2XY ordering.However,due to ergodic difficulties faced by Monte Carlo methods at low temperatures,this topological phase has not been numerically explored.We propose a linear cluster updating Monte Carlo method,which flips spins without rejection in the anisotropy limit but does not change the energy.Using this scheme and conventional Monte Carlo methods,we succeed in revealing the nature of topological phases with half-vortices and domain walls.In the constructed global phase diagram,Ising and XY-type transitions are very close to each other and differ significantly from the schematic phase diagram reported earlier.We also propose and explore a wide range of quantities,including magnetism,superfluidity,specific heat,susceptibility,and even percolation susceptibility,and obtain consistent and reliable results.Furthermore,we observed first-order transitions characterized by common intersection points in magnetizations for different system sizes,as opposed to the conventional phase transition where Binder cumulants of various sizes share common intersections.The critical exponents of different types of phase transitions are reasonably fitted.The results are useful to help cold atom experiments explore the half-vortex topological phase. 展开更多
关键词 topological phase transition Ising-XY model Monte Carlo method half vortex
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Mesopause temperatures and relative densities at midlatitudes observed by the Mengcheng meteor radar 被引量:2
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作者 Wen Yi XiangHui Xue +5 位作者 MaoLin Lu Jie Zeng HaiLun Ye JianFei Wu Chong Wang TingDi Chen 《Earth and Planetary Physics》 CAS CSCD 2023年第6期665-674,共10页
The atmospheric temperatures and densities in the mesosphere and lower thermosphere(MLT)region are essential for studying the dynamics and climate of the middle and upper atmosphere.In this study,we present more than ... The atmospheric temperatures and densities in the mesosphere and lower thermosphere(MLT)region are essential for studying the dynamics and climate of the middle and upper atmosphere.In this study,we present more than 9 years of mesopause temperatures and relative densities estimated by using ambipolar diffusion coefficient measurements observed by the Mengcheng meteor radar(33.4°N,116.5°E).The intercomparison between the meteor radar and Thermosphere Ionosphere Mesosphere Energetics and Dynamics/Sounding of the Atmosphere by Broadband Emission Radiometry(TIMED/SABER)and Earth Observing System(EOS)Aura/Microwave Limb Sounder(MLS)observations indicates that the meteor radar temperatures and densities agree well with the simultaneous satellite measurements.Annual variations dominate the mesopause temperatures,with the maximum during winter and the minimum during summer.The mesopause relative densities also show annual variations,with strong maxima near the spring equinox and weak maxima before the winter solstice,and with a minimum during summer.In addition,the mesopause density exhibits a structure similar to that of the zonal wind:as the zonal wind flows eastward(westward),the mesopause density decreases(increases).At the same time,the meridional wind shows a structure similar to that of the mesopause temperature:as the meridional wind shows northward(southward)enhancements,the mesopause temperature increases(decreases).Simultaneous horizontal wind,temperature,and density observations provide multiple mesospheric parameters for investigating mesospheric dynamics and thermodynamic processes and have the potential to improve widely used empirical atmospheric models. 展开更多
关键词 meteor radar MESOPAUSE horizontal wind temperature density
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Resting-state electroencephalography theta predicts neurofeedback treatment 4-month follow-up response in nicotine addiction 被引量:1
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作者 Qiujian Meng Ying Zhu +4 位作者 Ye Yuan Li Yang Jiafang Liu Xiaochu Zhang Junjie Bu 《General Psychiatry》 CSCD 2023年第4期303-311,共9页
Background The high rate of long-term relapse is a major cause of smoking cessation failure.Recently,neurofeedback training has been widely used in the treatment of nicotine addiction;however,approximately 30%of subje... Background The high rate of long-term relapse is a major cause of smoking cessation failure.Recently,neurofeedback training has been widely used in the treatment of nicotine addiction;however,approximately 30%of subjects fail to benefit from this intervention.Our previous randomised clinical trial(RCT)examined cognition-guided neurofeedback and demonstrated a significant decrease in daily cigarette consumption at the 4-month follow-up.However,significant individual differences were observed in the 4-month follow-up effects of decreased cigarette consumption.Therefore,it is critical to identify who will benefit from pre-neurofeedback.Aims We examined whether the resting-state electroencephalography(EEG)characteristics from pre-neurofeedback predicted the 4-month follow-up effects and explored the possible mechanisms.Methods This was a double-blind RCT.A total of 60 participants with nicotine dependence were randomly assigned to either the real-feedback or yoked-feedback group.They underwent 6 min closed-eye resting EEG recordings both before and after two neurofeedback sessions.A follow-up assessment was conducted after 4 months.Results The frontal resting-state theta power spectral density(PSD)was significantly altered in the real-feedback group after two neurofeedback visits.Higher theta PSD in the real-feedback group before neurofeedback was the only predictor of decreased cigarette consumption at the 4-month follow-up.Further reliability analysis revealed a significant positive correlation between theta PSD pre-neurofeedback and post-neurofeedback.A leave-one-out cross-validated linear regression of the theta PSD pre-neurofeedback demonstrated a significant correlation between the predicted and observed reductions in cigarette consumption at the 4-month follow-up.Finally,source analysis revealed that the brain mechanisms of the theta PSD predictor were located in the orbital frontal cortex.Conclusions Our study demonstrated changes in the resting-state theta PSD following neurofeedback training.Moreover,the resting-state theta PSD may serve as a prognostic marker of neurofeedback effects.A higher resting-state theta PSD predicts a better long-term response to neurofeedback treatment,which may facilitate the selection of individualised interventions. 展开更多
关键词 NICOTINE ADDICTION TREATMENT
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Resonant Charge Transport Assisted by the Molecular Vibration in Single-Molecule Junction from Time-Domain ab initio Nonadiabatic Molecular Dynamics Simulations
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作者 田韫哲 郑奇靖 赵瑾 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第12期92-97,共6页
Using ab initio nonadiabatic molecular dynamics simulation, we study the time-dependent charge transport dynamics in a single-molecule junction formed by gold(Au) electrodes and a single benzene-1,4-dithiol(BDT)molecu... Using ab initio nonadiabatic molecular dynamics simulation, we study the time-dependent charge transport dynamics in a single-molecule junction formed by gold(Au) electrodes and a single benzene-1,4-dithiol(BDT)molecule. Two different types of charge transport channels are found in the simulation. One is the routine nonresonant charge transfer path, which occurs in several picoseconds. The other is activated when the electronic state of the electrodes and that of the molecule get close in energy, which is referred to as the resonant charge transport. More strikingly, the resonant charge transfer occurs in an ultrafast manner within 100 fs, which notably increases the conductance of the device. Further analysis shows that the resonant charge transport is directly assisted by the B_(2) and A1 molecular vibration modes. Our study provides atomic insights into the time-dependent charge transport dynamics in single-molecule junctions, which is important for designing highly efficient single-molecule devices. 展开更多
关键词 charge RESONANT Molecular
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Revisiting the Role of Physical Confinement and Chemical Regulation of 3D Hosts for Dendrite-Free Li Metal Anode 被引量:3
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作者 Shufen Ye Xingjia Chen +8 位作者 Rui Zhang Yu Jiang Fanyang Huang Huijuan Huang Yu Yao Shuhong Jiao Xiang Chen Qiang Zhang Yan Yu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第11期290-306,共17页
Lithium metal anode has been demonstrated as the most promising anode for lithium batteries because of its high theoretical capacity,but infinite volume change and dendritic growth during Li electrodeposition have pre... Lithium metal anode has been demonstrated as the most promising anode for lithium batteries because of its high theoretical capacity,but infinite volume change and dendritic growth during Li electrodeposition have prevented its practical applications.Both physical morphology confinement and chemical adsorption/diffusion regulation are two crucial approaches to designing lithiophilic materials to alleviate dendrite of Li metal anode.However,their roles in suppressing dendrite growth for long-life Li anode are not fully understood yet.Herein,three different Ni-based nanosheet arrays(NiO-NS,Ni_(3)N-NS,and Ni_(5)P_(4)-NS)on carbon cloth as proof-of-concept lithiophilic frame-works are proposed for Li metal anodes.The two-dimensional nanoarray is more promising to facilitate uniform Li^(+)flow and electric field.Compared with the NiO-NS and the Ni_(5)P_(4)-NS,the Ni_(3)N-NS on carbon cloth after reacting with molten Li(Li-Ni/Li_(3)N-NS@CC)can afford the strongest adsorption to Li+and the most rapid Li+diffusion path.Therefore,the Li-Ni/Li_(3)N-NS@CC electrode realizes the lowest overpotential and the most excellent electrochemical performance(60 mA cm^(−2)and 60 mAh cm^(−2)for 1000 h).Furthermore,a remarkable full battery(LiFePO_(4)||Li-Ni/Li_(3)N-NS@CC)reaches 300 cycles at 2C.This research provides valuable insight into designing dendrite-free alkali metal batteries. 展开更多
关键词 Li metal anodes 3D carbon framework Ni-based nanosheets Physical morphology confinement Chemical adsorption/diffusion regulation
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Concentrated ternary ether electrolyte allows for stable cycling of a lithium metal battery with commercial mass loading high-nickel NMC and thin anodes
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作者 Jun Yang Xing Li +17 位作者 Ke Qu Yixian Wang Kangqi Shen Changhuan Jiang Bo Yu Pan Luo Zhuangzhi Li Mingyang Chen Bingshu Guo Mingshan Wang Junchen Chen Zhiyuan Ma Yun Huang Zhenzhong Yang Pengcheng Liu Rong Huang Xiaodi Ren David Mitlin 《Carbon Energy》 SCIE CSCD 2023年第3期2-18,共17页
A new concentrated ternary salt ether-based electrolyte enables stable cycling of lithium metal battery(LMB)cells with high-mass-loading(13.8 mg cm^(−2),2.5 mAh cm^(−2))NMC622(LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2))cathodes ... A new concentrated ternary salt ether-based electrolyte enables stable cycling of lithium metal battery(LMB)cells with high-mass-loading(13.8 mg cm^(−2),2.5 mAh cm^(−2))NMC622(LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2))cathodes and 50μm Li anodes.Termed“CETHER-3,”this electrolyte is based on LiTFSI,LiDFOB,and LiBF4 with 5 vol%fluorinated ethylene carbonate in 1,2-dimethoxyethane.Commer-cial carbonate and state-of-the-art binary salt ether electrolytes were also tested as baselines.With CETHER-3,the electrochemical performance of the full-cell battery is among the most favorably reported in terms of high-voltage cycling stability.For example,LiNi_(x)Mn_(y)Co_(1-x-y)O_(2)(NMC)-Li metal cells retain 80%capacity at 430 cycles with a 4.4 V cut-off and 83%capacity at 100 cycles with a 4.5 V cut-off(charge at C/5,discharge at C/2).According to simulation by density functional theory and molecular dynamics,this favorable performance is an outcome of enhanced coordination between Li^(+)and the solvent/salt molecules.Combining advanced microscopy(high-resolution transmission electron microscopy,scanning electron microscopy)and surface science(X-ray photoelectron spectroscopy,time-of-fight secondary ion mass spectroscopy,Fourier-transform infrared spectroscopy,Raman spectroscopy),it is demonstrated that a thinner and more stable cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)are formed.The CEI is rich in lithium sulfide(Li_(2)SO_(3)),while the SEI is rich in Li_(3)N and LiF.During cycling,the CEI/SEI suppresses both the deleterious transformation of the cathode R-3m layered near-surface structure into disordered rock salt and the growth of lithium metal dendrites. 展开更多
关键词 concentrated electrolyte density functional theory ether electrolyte high‐nickel cathode high‐voltage battery molecular dynamics
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Overcoming the Na-ion conductivity bottleneck for the cost-competitive chloride solid electrolytes
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作者 Lv Hu Hui Li +3 位作者 Fang Chen Yating Liu Jinzhu Wang Cheng Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期1-8,I0001,共9页
Chloride solid electrolytes possess multiple advantages for the construction of safe,energy-dense allsolid-state sodium batteries,but presently the chlorides with sufficiently high cost-competitiveness for commerciali... Chloride solid electrolytes possess multiple advantages for the construction of safe,energy-dense allsolid-state sodium batteries,but presently the chlorides with sufficiently high cost-competitiveness for commercialization almost all exhibit low Na-ion conductivities of around 10^(-5)S cm^(-1)or lower.Here,we report a chloride solid electrolyte,Na_(2.7)ZFCl_(5.3)O_(0.7),which reaches a Na-ion conductivity of 2.29×10^(-4)S cm^(-1)at 25℃without involving overly expensive raw materials such as rare-earth chlorides or Na_(2)S.In addition to the efficient ion transport,Na_(2.7)ZrCl_(5.3)O_(0.7)also shows an excellent deformability surpassing that of the widely studied Na_(3)PS_(4),Na_(3)SbS_(4),and Na_(2)ZrCl_(6)solid electrolytes.The combination of these advantages allows the all-solid-state cell based on Na_(2.7)ZrCl_(5.3)O_(0.7)and NaCrO_(2)to realize stable room-temperature cycling at a much higher specific current than those based on other non-viscoelastic chloride solid electrolytes in literature(120 mA g^(-1)vs.12-55 mA g^(-1));after 100 cycles at such a high rate,the Na_(2.7)ZFCl_(5.3)O_(0.7)-based cell can still deliver a discharge capacity of 80 mAh g^(-1)at25℃. 展开更多
关键词 All-solid-state sodium batteries Ionic conductivities Solid electrolytes Chlorides High voltage stability
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Modulating Co-Co bonds average length in Co_(0.85)Se_(1-x)S_(x) to enhance conversion reaction for potassium storage
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作者 Daming Chen Yuchun Liu +5 位作者 Pan Feng Xiao Tao Zhiquan Huang Xiyu Zhang Min Zhou Jian Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期111-121,共11页
While alloying transition metal chalcogenides(TMCs)with other chalcogen elements can effectively improve their conductivity and electrochemical properties,the optimal alloying content is still uncertain.In this study,... While alloying transition metal chalcogenides(TMCs)with other chalcogen elements can effectively improve their conductivity and electrochemical properties,the optimal alloying content is still uncertain.In this study,we study the influence of dopant concentration on the chemical bonds in TMC and reveal the associated stepwise conversion reaction mechanism for potassium ion storage.According to density function theory calculations,appropriate S-doping in Co0.85Se(Co_(0.85)Se_(1-x)S_(x))can reduce the average length of Co-Co bonds because of the electronegativity variation,which is thermodynamically favourable to the phase transition reactions.The optimal Se/S ratio(x=0.12)for the conductivity has been obtained from experimental results.When assembled as an anode in potassium-ion batteries(PIBs),the sample with optimized Se/S ratio exhibits extraordinary electrochemical performance.The rate performance(229.2 mA h g^(-1)at 10 A g^(-1))is superior to the state-of-the-art results.When assembled with Prussian blue(PB)as a cathode,the pouch cell exhibits excellent performance,demonstrating its great potential for applications.Moreover,the stepwise K+storage mechanism caused by the coexistence of S and Se is revealed by in-situ X-ray diffraction and ex-situ transmission electron microscopy techniques.Hence,this work not only provides an effective strategy to enhance the electrochemical performance of transition metal chalcogenides but also reveals the underlying mechanism for the construction of advanced electrode materials. 展开更多
关键词 Co_(0.85)Se_(1-x)S_(x) Co-Co bonds Phase transition reactions Optimal Se/s Potassium ion batteries
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Absolute partial and total ionization cross sections of carbon monoxide with electron collision from 350 eV to 8000 eV
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作者 Taj Wali Khan 黄伟哲 +2 位作者 王恩亮 单旭 陈向军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期459-464,共6页
The absolute partial and total cross sections for electron impact ionization of carbon monoxide are reported for electron energies from 350 eV to 8000 eV.The product ions(CO^(+),C^(+),O^(+),CO^(2+),C^(2+),and O^(2+))a... The absolute partial and total cross sections for electron impact ionization of carbon monoxide are reported for electron energies from 350 eV to 8000 eV.The product ions(CO^(+),C^(+),O^(+),CO^(2+),C^(2+),and O^(2+))are measured by employing an ion imaging mass spectrometer and two ion-pair dissociation channels(C^(+)+O^(+)and C^(2+)+O^(+))are identified.The absolute cross sections for producing individual ions and their total,as well as for the ion-pair dissociation channels are obtained by normalizing the data of CO^(+)to that of Ar^(+)from CO-Ar mixture target with a fixed 1:1 ratio.The overall errors are evaluated by considering various kinds of uncertainties.A comprehensive comparison is made with the available data,which shows a good agreement with each other over the energy ranges that are overlapped.This work presents new cross-section data with electron energies above 1000 eV. 展开更多
关键词 electron impact ionization cross sections carbon monoxide ion imaging mass spectrometer
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Ab initio nonadiabatic molecular dynamics study on spin–orbit coupling induced spin dynamics in ferromagnetic metals
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作者 朱万松 郑镇法 +1 位作者 郑奇靖 赵瑾 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期156-163,共8页
Understanding the photoexcitation induced spin dynamics in ferromagnetic metals is important for the design of photo-controlled ultrafast spintronic device.In this work,by the ab initio nonadiabatic molecular dynamics... Understanding the photoexcitation induced spin dynamics in ferromagnetic metals is important for the design of photo-controlled ultrafast spintronic device.In this work,by the ab initio nonadiabatic molecular dynamics simulation,we have studied the spin dynamics induced by spin–orbit coupling(SOC)in Co and Fe using both spin-diabatic and spin-adiabatic representations.In Co system,it is found that the Fermi surface(E_(F))is predominantly contributed by the spin-minority states.The SOC induced spin flip will occur for the photo-excited spin-majority electrons as they relax to the E_(F),and the spin-minority electrons tend to relax to the EFwith the same spin through the electron–phonon coupling(EPC).The reduction of spin-majority electrons and the increase of spin-minority electrons lead to demagnetization of Co within100 fs.By contrast,in Fe system,the E_(F) is dominated by the spin-majority states.In this case,the SOC induced spin flip occurs for the photo-excited spin-minority electrons,which leads to a magnetization enhancement.If we move the E_(F) of Fe to higher energy by 0.6eV,the E_(F) will be contributed by the spin-minority states and the demagnetization will be observed again.This work provides a new perspective for understanding the SOC induced spin dynamics mechanism in magnetic metal systems. 展开更多
关键词 nonadiabatic molecular dynamics spin dynamics spin–orbit coupling ferromagnetic metal
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Holevo bound independent of weight matrices for estimating two parameters of a qubit
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作者 牛畅 郁司夏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期137-143,共7页
Holevo bound plays an important role in quantum metrology as it sets the ultimate limit for multi-parameter estimations,which can be asymptotically achieved.Except for some trivial cases,the Holevo bound is implicitly... Holevo bound plays an important role in quantum metrology as it sets the ultimate limit for multi-parameter estimations,which can be asymptotically achieved.Except for some trivial cases,the Holevo bound is implicitly defined and formulated with the help of weight matrices.Here we report the first instance of an intrinsic Holevo bound,namely,without any reference to weight matrices,in a nontrivial case.Specifically,we prove that the Holevo bound for estimating two parameters of a qubit is equivalent to the joint constraint imposed by two quantum Cramér–Rao bounds corresponding to symmetric and right logarithmic derivatives.This weightless form of Holevo bound enables us to determine the precise range of independent entries of the mean-square error matrix,i.e.,two variances and one covariance that quantify the precisions of the estimation,as illustrated by different estimation models.Our result sheds some new light on the relations between the Holevo bound and quantum Cramer–Rao bounds.Possible generalizations are discussed. 展开更多
关键词 quantum metrology quantum Fisher information Holevo bound quantum multi-parameter estimation
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Observation of flat-band localized state in a one-dimensional diamond momentum lattice of ultracold atoms
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作者 曾超 石悦然 +5 位作者 毛一屹 武菲菲 谢岩骏 苑涛 戴汉宁 陈宇翱 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期212-217,共6页
We investigated the one-dimensional diamond ladder in the momentum lattice platform. By inducing multiple twoand four-photon Bragg scatterings among specific momentum states, we achieved a flat band system based on th... We investigated the one-dimensional diamond ladder in the momentum lattice platform. By inducing multiple twoand four-photon Bragg scatterings among specific momentum states, we achieved a flat band system based on the diamond model, precisely controlling the coupling strength and phase between individual lattice sites. Utilizing two lattice sites couplings, we generated a compact localized state associated with the flat band, which remained localized throughout the entire time evolution. We successfully realized the continuous shift of flat bands by adjusting the corresponding nearest neighbor hopping strength, enabling us to observe the complete localization process. This opens avenues for further exploration of more complex properties within flat-band systems, including investigating the robustness of flat-band localized states in disordered flat-band systems and exploring many-body localization in interacting flat-band systems. 展开更多
关键词 diamond lattice flat band momentum lattice localized state
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Oxygen‑Coordinated Single Mn Sites for Efficient Electrocatalytic Nitrate Reduction to Ammonia
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作者 Shengbo Zhang Yuankang Zha +8 位作者 Yixing Ye Ke Li Yue Lin Lirong Zheng Guozhong Wang Yunxia Zhang Huajie Yin Tongfei Shi Haimin Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期147-159,共13页
Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites... Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption spectroscopy.As a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(vs.reversible hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(vs.RHE)under ambient conditions.Further,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H cell.The in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites. 展开更多
关键词 Atomically dispersed Oxygen coordination Nitrate reduction reaction In situ spectroscopic studies Hydrogen evolution reaction
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NIR-II fluorescence imaging in liver tumor surgery: A narrative review
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作者 Zihao Liu Lifeng Yan +1 位作者 Qingsong Hu Dalong Yin 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第1期29-44,共16页
In liver tumor surgery,the recognition of tumor margin and radical resection of microcancer focis have always been the crucial points to reduce postoperative recurrence of tumor.However,naked-eye inspection and palpat... In liver tumor surgery,the recognition of tumor margin and radical resection of microcancer focis have always been the crucial points to reduce postoperative recurrence of tumor.However,naked-eye inspection and palpation have limited effectiveness in identifying tumor boundaries,and traditional imaging techniques cannot consistently locate tumors in real time.As an intraoperative real-time navigation imaging method,NIRfluorescence imaging has been extensively studied for its simplicity,reliable safety,and superior sensitivity,and is expected to improve the accuracy of liver tumor surgery.In recent years,the research focus of NIRfluorescence has gradually shifted from the-rst near-infrared window(NIR-I,700–900 nm)to the second near-infrared window(NIR-II,1000–1700 nm).Fluorescence imaging in NIR-II reduces the scattering effect of deep tissue,providing a preferable detection depth and spatial resolution while signi-cantly eliminating liver autofluorescence background to clarify tumor margin.Developingfluorophores combined with tumor antibodies will further improve the precision offluorescence-guided surgical navigation.With the development of a bunch offluorophores with phototherapy ability,NIR-II can integrate tumor detection and treatment to explore a new therapeutic strategy for liver cancer.Here,we review the recent progress of NIR-IIfluorescence technology in liver tumor surgery and discuss its challenges and potential development direction. 展开更多
关键词 Fluorescence guided-surgery liver cancer near infrared-II optical imaging
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Structural and Ferroelectric Transition in Few-Layer HfO_(2) Films by First Principles Calculations
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作者 Ruiling Gao Chao Liu +9 位作者 Bowen Shi Yongchang Li Bing Luo Rui Chen Wenbin Ouyang Heng Gao Shunbo Hu Yin Wang Dongdong Li Wei Ren 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第8期94-106,共13页
The discovery of ferroelectricity in HfO_(2)-based materials with high dielectric constant has inspired tremendous research interest for next-generation electronic devices.Importantly,films structure and strain are ke... The discovery of ferroelectricity in HfO_(2)-based materials with high dielectric constant has inspired tremendous research interest for next-generation electronic devices.Importantly,films structure and strain are key factors in exploration of ferroelectricity in fluorite-type oxide HfO_(2) films.Here we investigate the structures and straininduced ferroelectric transition in different phases of few-layer HfO_(2) films(layer number𝑁=1–5).It is found that HfO_(2) films for all phases are more stable with increasing films thickness.Among them,the Pmn2_(1)(110)-oriented film is most stable,and the films of𝑁=4,5 occur with a𝑃21 ferroelectric transition under tensile strain,resulting in polarization about 11.8μC/cm^(2) along in-plane𝑎-axis.The ferroelectric transition is caused by the strain,which induces the displacement of Hf and O atoms on the surface to non-centrosymmetric positions away from the original paraelectric positions,accompanied by the change of surface Hf–O bond lengths.More importantly,three new stable HfO_(2)2D structures are discovered,together with analyses of computed electronic structures,mechanical,and dielectric properties.This work provides guidance for theoretical and experimental study of the new structures and strain-tuned ferroelectricity in freestanding HfO_(2) films. 展开更多
关键词 properties. FERROELECTRIC POSITIONS
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Defect engineering: A versatile tool for tuning the activation of key molecules in photocatalytic reactions 被引量:7
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作者 Ning Zhang Chao Gao Yujie Xiong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第10期43-57,共15页
Many photocatalytic reactions such as CO2 reduction and N2 fixation are often limited by the activation of some key molecules. Defects in solid materials can robustly introduce coordinately unsaturated sites to serve ... Many photocatalytic reactions such as CO2 reduction and N2 fixation are often limited by the activation of some key molecules. Defects in solid materials can robustly introduce coordinately unsaturated sites to serve as highly active sites for molecular chemisorption and activation. As a result, rational defect engineering has endowed a versatile approach to further develop photocatalytic applications beyond water splitting. The subtly designed defects in photocatalysts can play critical and decisive roles in molecular activation as proven in recent years. The defects cannot only serve as active sites for molecular chemisorption, but also spatially supply channels for energy and electron transfer. In this review, we aim to summarize the diversiform photocatalytic applications using defects as active sites, including but not limited to CO2 reduction, O2 activation,H2O dissociation, N2 fixation as well as activation of other molecules. In particular, we emphatically outline how the parameters of defects (e.g.,concentration,location,geometric and electronic structures) can serve as the knobs for maneuvering molecular adsorption and activation as well as altering subsequent reaction pathway. Moreover, we underline the remaining challenges at the current stage and the potential development in the future.It is anticipated that this review consolidates the in-depth understanding towards the structure-activity relationship between defects and related reactions. 展开更多
关键词 DEFECT engineering PHOTOCATALYSIS MOLECULAR adsorption MOLECULAR activation Electron transfer
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Synthesis and Photocatalytic Activity of One-dimensional ZnO-Zn2SnO4 Mixed Oxide Nanowires 被引量:2
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作者 Xue-lian Bai Nan Pan Xiao-ping Wang Hai-qian Wang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第1期81-86,共6页
混合氧化物光催化剂,有不同尺寸的 ZnO-Zn2SnO4 (ZnO-ZTO ) nanowires 被一个简单热蒸发方法准备。ZnO-ZTO nanowires 与一台扫描电子显微镜, X 光检查衍射,高分辨率的传播电子显微镜学,精力散的分光计,和 X 光检查光电子系列被描... 混合氧化物光催化剂,有不同尺寸的 ZnO-Zn2SnO4 (ZnO-ZTO ) nanowires 被一个简单热蒸发方法准备。ZnO-ZTO nanowires 与一台扫描电子显微镜, X 光检查衍射,高分辨率的传播电子显微镜学,精力散的分光计,和 X 光检查光电子系列被描绘。ZnO-ZTO 的 photocatalytic 活动混合了 nanowires 被观察甲基橘子的 photodegradation 行为学习水的答案。结果建议 ZnO-ZTO 混合了氧化物 nanowires 比纯 ZnO 和 Zn2SnO4 nanowires 举办一项更高的 photocatalytic 活动。在溶液的光催化剂集中清楚地影响降级率,和我们更高的 photodegradation 效率能与 ZnO-ZTO nanowire 催化剂的更小的数量被完成的结果表演,作为与纯 ZnO 和 ZTO nanowires 相比。而且, photocatalytic 活动能被减少 nanowires 的平均直径也提高。纯 ZnO 和 ZTO nanowires 的活动被身体上混合他们也提高。这些结果能被在二个半导体之间的协同解释。 展开更多
关键词 氧化锌 锡酸锌 纳米线 光催化活性 光降解 制备
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Morphology-dependent structures and catalytic performances of Au nanostructures on Cu_2O nanocrystals synthesized by galvanic replacement reaction 被引量:2
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作者 Zhenhua Zhang Rui Song +1 位作者 Tian Cao Weixin Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第6期1086-1091,共6页
Au nanostructures were prepared on uniform Cu2O octahedra and rhombic dodecahedra via the galvanic replacement reaction between HAuCl 4 and Cu2O. The compositions and structures were studied by Scanning Electron Micro... Au nanostructures were prepared on uniform Cu2O octahedra and rhombic dodecahedra via the galvanic replacement reaction between HAuCl 4 and Cu2O. The compositions and structures were studied by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), High-Resolution Transmission Electron Microscope (HRTEM), X-Ray Diffraction (XRD), X-Ray Absorption Spectroscopy (XAS), X-ray Photoelectron Spectroscopy (XPS) and in-situ DRIFTS spectroscopy of CO adsorption. Different from the formation of Au-Cu alloys on Cu2O cubes by the galvanic replacement reaction (ChemNanoMat 2 (2016) 861-865), metallic Au particles and positively-charged Au clusters form on Cu2O octahedra and rhombic dodecahedra at very small Au loadings and only metallic Au particles form at large Au loadings. Metallic Au particles on Cu2O octahedra and rhombic dodecahedra are more active in catalyzing the liquid phase aerobic oxidation reaction of benzyl alcohol than positively-charged Au clusters. These results demonstrate an obvious morphology effect of Cu2O nanocrystals on the liquid-solid interfacial reactions and prove oxide morphology as an effective strategy to tune the surface reactivity and catalytic performance. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved. 展开更多
关键词 Au/Cu2O nanocomposites Galvanic replacement reaction Liquid-solid interfacial reaction Crystal plane effect Aerobic oxidation of benzyl alcohol
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Synthesis of dihydrocapsaicin and dihydrocapsiate exclusively from lignocellulosic platform chemicals 被引量:2
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作者 Yan-Bing Li Hui-Ying Guo +1 位作者 Chen-Qiang Deng Jin Deng 《Green Energy & Environment》 SCIE EI CSCD 2022年第3期519-524,共6页
Biorefinery is pivotal to the sustainability of modern chemical industry.However,since biomass is oxygen-enriched,new and green chemical strategies are required for expanding the biomass derived chemical space.In this... Biorefinery is pivotal to the sustainability of modern chemical industry.However,since biomass is oxygen-enriched,new and green chemical strategies are required for expanding the biomass derived chemical space.In this work,synthesis of natural products dihydrocapsaicin and dihydrocapsiate was achieved exclusively from lignocellulosic platform chemicals.Natural products dihydrocapsaicin and dihydrocapsiate were synthesized exclusively from lignocellulosic platform chemicals,using furfural(from hemicellulose)and methyl isopropyl ketone(from cellulose)through aldol condensation-hydrolysis-hydrodeoxygenation to synthesize 8-methylnonanoic acid and then combined with vanillin derivates(from lignin).This synthesis demonstrates the feasibility of constructing natural products entirely from renewable biomass platform through green processes.The utilization of inherent functional groups of biomass demonstrates their potential to open up chemical space. 展开更多
关键词 SPACE SYNTHESIS HYDROLYSIS
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