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基于SFODLPME-HPLC-QAMS法测定金银花中黄酮类成分含量的研究
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作者 金绍娣 顾东雅 +2 位作者 裴丽 顾晨露 朱驯 《化学与生物工程》 北大核心 2026年第1期64-70,共7页
采用悬浮固化液相微萃取(SFODLPME)联合高效液相色谱(HPLC)及一测多评法(QAMS),建立了金银花中芦丁、金丝桃苷、木犀草苷、忍冬苷、苜蓿素、木犀草素、槲皮素和穗花杉双黄酮等8种黄酮类成分的同步测定方法。通过单因素实验优化了萃取条... 采用悬浮固化液相微萃取(SFODLPME)联合高效液相色谱(HPLC)及一测多评法(QAMS),建立了金银花中芦丁、金丝桃苷、木犀草苷、忍冬苷、苜蓿素、木犀草素、槲皮素和穗花杉双黄酮等8种黄酮类成分的同步测定方法。通过单因素实验优化了萃取条件,并以芦丁为内参物建立了其他成分的相对校正因子计算模型,系统考察了该方法在不同色谱条件下的适用性。结果表明,最佳SFODLPME萃取条件为:以40μL正十二醇为萃取剂、0.1 mol·L^(-1)盐酸加量150μL、萃取时间30 min,该条件下各成分富集效果好、色谱峰形佳、干扰少;建立的相对校正因子在不同仪器、色谱柱、流速下的重现性良好(RSD<2.0%);一测多评法测定结果与外标法无显著差异。该方法首次实现了金银花中穗花杉双黄酮的鉴别,具有绿色、高效、成本低、灵敏度高等优点,适用于金银花中多种黄酮类成分的纯化与检测。 展开更多
关键词 悬浮固化液相微萃取 一测多评 金银花 黄酮
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一种高阶QAM多模式信号实时解调方案设计
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作者 李大芳 《西南民族大学学报(自然科学版)》 2026年第1期70-77,共8页
针对高阶QAM解调的解调性能损失大及实时性差等问题,通过仿真验证给出了一种适用于工程应用的实时解调方案,该方案适用于从4QAM到1024QAM八种调制模式,码速率4.8 ksps~8192 ksps连续可调.仿真结果及实际应用表明,该解调方案仅有1024QAM... 针对高阶QAM解调的解调性能损失大及实时性差等问题,通过仿真验证给出了一种适用于工程应用的实时解调方案,该方案适用于从4QAM到1024QAM八种调制模式,码速率4.8 ksps~8192 ksps连续可调.仿真结果及实际应用表明,该解调方案仅有1024QAM模式下的解调损失超过3 dB,其余模式下的解调损失均不超过3 dB,解调方案具有结构简单、实现方便、解调性能高、实时性好等特点. 展开更多
关键词 qam解调 定时恢复 载波恢复
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QAM信号基于泰勒补偿的离网格直接定位算法
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作者 牛芳 刘国亮 +2 位作者 康小亮 张继龙 韦仪 《现代雷达》 北大核心 2026年第2期35-41,共7页
文中深入研究正交幅度调制(QAM)信号的离网格直接定位(DP)问题。现有DP算法普遍存在计算复杂度较高与离网格模型误差的问题,导致定位性能受限。针对上述问题,文中提出了一种基于泰勒补偿的QAM信号的离网格DP算法。该算法充分利用多嵌套... 文中深入研究正交幅度调制(QAM)信号的离网格直接定位(DP)问题。现有DP算法普遍存在计算复杂度较高与离网格模型误差的问题,导致定位性能受限。针对上述问题,文中提出了一种基于泰勒补偿的QAM信号的离网格DP算法。该算法充分利用多嵌套阵列接收QAM信号的特性,在抑制高斯噪声的同时增大天线孔径,进而有效提升系统可用自由度。此外,利用离散傅里叶变换构建一种计算高效的DP代价函数,以减少由穷尽网格搜索带来的高计算复杂度,并利用一阶泰勒级数展开技术对位置估计偏差进行精准计算与补偿,以此提高定位精度。数值仿真结果表明,所提算法的定位精度优于传统的基于空间平滑的子空间数据融合DP算法与Capon DP算法,同时保持了较低的计算复杂度。 展开更多
关键词 离网格 正交幅度调制信号 直接定位 泰勒补偿
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Peak current reduction in presence of RF phase modulationin the dual RF system
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作者 Jiang Bocheng Zhang Yao Tsai Cheng-Ying 《强激光与粒子束》 北大核心 2026年第1期160-165,共6页
[Background]High harmonic cavities are widely used in electron storage rings to lengthen thebunch,lower the bunch peak current,thereby reducing the IBS effect,enhancing the Touschek lifetime,as well asproviding Landau... [Background]High harmonic cavities are widely used in electron storage rings to lengthen thebunch,lower the bunch peak current,thereby reducing the IBS effect,enhancing the Touschek lifetime,as well asproviding Landau damping,which is particularly important for storage rings operating with ultra-low emittance or atlow beam energy.[Purpose]To further increase the bunch length without additional hardware costs,the phasemodulation in a dual-RF system is considered.[Methods]In this paper,turn-by-turn simulations incorporating randomsynchrotron radiation excitation are conducted,and a brief analysis is presented to explain the bunch lengtheningmechanism.[Results]Simulation results reveal that the peak current can be further reduced,thereby mitigating IBSeffects and enhancing the Touschek lifetime.Although the energy spread increases,which tends to reduce thebrightness of higher-harmonic radiation from the undulator,the brightness of the fundamental harmonic can,in fact,beimproved. 展开更多
关键词 dual high-frequency system phase modulation beam bunch stretching intra-beam scattering
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Evaluation of Reinforcement Learning-Based Adaptive Modulation in Shallow Sea Acoustic Communication
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作者 Yifan Qiu Xiaoyu Yang +1 位作者 Feng Tong Dongsheng Chen 《哈尔滨工程大学学报(英文版)》 2026年第1期292-299,共8页
While reinforcement learning-based underwater acoustic adaptive modulation shows promise for enabling environment-adaptive communication as supported by extensive simulation-based research,its practical performance re... While reinforcement learning-based underwater acoustic adaptive modulation shows promise for enabling environment-adaptive communication as supported by extensive simulation-based research,its practical performance remains underexplored in field investigations.To evaluate the practical applicability of this emerging technique in adverse shallow sea channels,a field experiment was conducted using three communication modes:orthogonal frequency division multiplexing(OFDM),M-ary frequency-shift keying(MFSK),and direct sequence spread spectrum(DSSS)for reinforcement learning-driven adaptive modulation.Specifically,a Q-learning method is used to select the optimal modulation mode according to the channel quality quantified by signal-to-noise ratio,multipath spread length,and Doppler frequency offset.Experimental results demonstrate that the reinforcement learning-based adaptive modulation scheme outperformed fixed threshold detection in terms of total throughput and average bit error rate,surpassing conventional adaptive modulation strategies. 展开更多
关键词 Adaptive modulation Shallow sea underwater acoustic modulation Reinforcement learning
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Unlocking Wavelength-Selective Modulations of Open-Circuit Voltage in Metal Halide Perovskite Solar Cells
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作者 Younsuk Hu Jibeom Hong +3 位作者 Kyounguk Cho Wanseung Yoo Doo Hyun Ko Inchan Hwang 《Energy & Environmental Materials》 2026年第1期329-340,共12页
The photovoltaic performance of metal halide perovskite solar cells often respond divergently to environmental conditions during storage.In particular,light exposure can either enhance or degrade device efficiency,yet... The photovoltaic performance of metal halide perovskite solar cells often respond divergently to environmental conditions during storage.In particular,light exposure can either enhance or degrade device efficiency,yet the mechanisms underlying these antithetical behaviors are still under investigation.In this study,we explore the modulation of the open-circuit voltage(Voc)in triple-cation mixed-halide perovskite solar cells by systematically controlling storage environments.While light intensity exhibits minimal impact during storage,the spectral composition of illumination selectively enhances Voc comprising reversible and irreversible contributions.Structural characterization reveals that prolonged storage degrades the quality of perovskite crystals in the upper region of the perovskite layer,whereas light storage promotes the relaxation of microstrain at the buried interface with a p-type organic layer.This structural reorganization at the interface,accompanied by lattice expansion,accounts for suppressed nonradiative recombination and a corresponding increase in quasi-Fermi level splitting.Consequently,devices fabricated without chemical defect passivation achieve a power conversion efficiency of higher than 40%under indoor lighting conditions after preconditioned by continuous exposure to ambient light during storage.These findings highlight the critical role of controlled light exposure during storage not only in enhancing efficiency,but also in ensuring reproducibility of perovskite solar cell characterization. 展开更多
关键词 indoor photovoltaics light-induced modulations perovskite solar cells REPRODUCIBILITY strain relaxation
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Lattice-oxygen modulation for redox stabilization and multi-electron transfer in lithium-rich cathodes
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作者 Mingche Huang Ruian Fan +5 位作者 Chenkai Sun Aoshen Duan Hao Cheng Ruguang Ma Erhong Song Jianjun Liu 《Materials Reports(Energy)》 2026年第1期94-102,共9页
Lithium-rich layered oxides(LRLOs)are promising cathode materials due to their high specific capacity,energy density,and operating voltage.However,their performance is hindered by the limited redox activity of transit... Lithium-rich layered oxides(LRLOs)are promising cathode materials due to their high specific capacity,energy density,and operating voltage.However,their performance is hindered by the limited redox activity of transition metals,leading to oxygen redox instability,oxygen release,and capacity degradation.To address these issues,we propose an innovative lattice-oxygen modulation(LOM)strategy that incorporates Mn^(3+)and Ti^(4+)into the Li_(1.2)Cr_(0.3)Mn_(0.4)Ti_(0.1)O_(2) system,effectively mitigating Cr migration,stabilizing oxygen redox reactions,and reinforcing structural integrity.This results in improved electrochemical performance,as demonstrated by a 56.5 mAh g^(−1) increase in initial discharge capacity to 364.2 mAh g^(−1),with 71.3%capacity retention after 30 cycles,reflecting a 20.2%improvement in cycling stability.Density functional theory(DFT)calculations confirm enhanced Cr redox reversibility and reduced oxygen evolution,further strengthening structural stability.These synergistic effects highlight the pivotal role of the LOM strategy in optimizing both electrochemical performance and structural integrity,offering a scalable pathway to improve capacity and cycling stability in lithium-rich cathodes. 展开更多
关键词 Lithium-rich cathodes Oxygen modulation Redox stabilization Multi-electron transfer enhancement Lattice reinforcement
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Tea polyphenol polymer film enables broadband optical modulation for hybrid mode-locked ultrafast fiber lasers
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作者 Wei Chen Kang Li +4 位作者 Cheng Gao Qingping Hu Zhengfan Li Yi Xiong Yunzhou Sun 《Chinese Physics B》 2026年第2期442-450,共9页
Materials exhibiting broadband nonlinear optical responses are critically important for ultrafast photonics applications,particularly as saturable absorbers(SAs)that facilitate broadband optical pulse generation.In th... Materials exhibiting broadband nonlinear optical responses are critically important for ultrafast photonics applications,particularly as saturable absorbers(SAs)that facilitate broadband optical pulse generation.In this study,tea polyphenolpolyvinyl alcohol(TP-PVA)composite films are synthesized via a polymer embedding method and employed as SAs to initiate ultrafast pulse operation in fiber lasers.The TP-PVA SA film exhibits excellent broadband saturable absorption performance at wavelengths of 1.0μm,1.5μm,and 2.0μm,with modulation depths of 54.21%,41.41%,and 51.16%,respectively.Stable passively mode-locked pulses with pulse widths of 588 fs,419 fs,and 743 fs are generated in Yb-,Er-,and Tm-doped fiber lasers,respectively.This work confirms the effective performance of TP-PVA as a broadband SA,and establishes a foundation for the integration of novel and sustainable materials within ultrafast photonic systems.The approach paves the way for developing compact broadband ultrafast laser systems operating in the near-infrared spectral region. 展开更多
关键词 ultrafast fiber lasers saturable absorbers broadband modulators natural dyes tea polyphenol
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Double-side delay alignment modulation for multi-user millimeter wave and terahertz communications
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作者 Xingwei Wang Haiquan Lu +1 位作者 Jieni Zhang Yong Zeng 《Digital Communications and Networks》 2026年第1期11-24,共14页
Delay Alignment Modulation(DAM)is an innovative broadband modulation technique well-suited for millimeter Wave(mm Wave)and Terahertz(THz)massive Multiple-Input Multiple-Output(MIMO)communication systems.Leveraging the... Delay Alignment Modulation(DAM)is an innovative broadband modulation technique well-suited for millimeter Wave(mm Wave)and Terahertz(THz)massive Multiple-Input Multiple-Output(MIMO)communication systems.Leveraging the high spatial resolution and sparsity of multi-path channels,DAM effectively mitigates Inter-Symbol Interference(ISI)by aligning all multi-path components through a combination of delay pre-compensation(or post-compensation)and path-based beamforming.As such,ISI is eliminated while preserving multi-path power gains.In this paper,we investigate multi-user double-side DAM,which incorporates both delay pre-compensation at the transmitter and post-compensation at the receiver,in contrast to prior works that primarily focus on singleside DAM with only delay pre-compensation.Firstly,we derive the constraint on the number of introduced delays and formulate the corresponding delay pre/post-compensation vectors tailored for multi-user double-side DAM,given a specific number of delay compensations.Furthermore,we demonstrate that when the number of Base Stations(BSs)/User Equipment(UE)antennas is sufficiently large,single-side DAM—where delay compensation is performed only at the BS/UE—is preferable to double-side DAM,since the former results in less ISI to be spatially eliminated.Next,we propose two low-complexity path-based beamforming strategies based on the eigen-beamforming transmission and ISI-Zero Forcing(ZF),respectively.On this basis,we further analyze the achievable sum rates.Simulation results verify that with a sufficiently large number of BS/UE antennas,singleside DAM is adequate for ISI elimination.Moreover,compared to the benchmarking scheme of Orthogonal Frequency Division Multiplexing(OFDM),multi-user BS-side DAM achieves higher spectral efficiency and lower Peak-to-Average Power Ratio(PAPR). 展开更多
关键词 Delay alignment modulation Delay pre-compensation Delay post-compensation Path-based beamforming Fractional channel delay
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Dual-region synergistic modulation and (101) facet engineering for highly reversible zinc anodes
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作者 Shuai Zhang Kittima Lolupiman +5 位作者 Dongdong Zhang Zixuan Gao Rungroj Chanajaree Xinyu Zhang Jin Cao Jiaqian Qin 《Advanced Powder Materials》 2026年第1期99-111,共13页
Aqueous zinc-ion batteries(AZIBs)offer promising safety and affordability,but suffer from dendritic Zn growth and parasitic side reactions at the electrode-electrolyte interface.Herein,we construct a dual-region inter... Aqueous zinc-ion batteries(AZIBs)offer promising safety and affordability,but suffer from dendritic Zn growth and parasitic side reactions at the electrode-electrolyte interface.Herein,we construct a dual-region interfacial modulation framework by molecularly reconfiguring the Helmholtz double layer via trace methyl methacrylate(MMA).Exploiting its amphiphilic and functionally asymmetric architecture,MMA enables a coordinated interfacial reconstruction that disrupts Zn^(2+)solvation in the outer Helmholtz plane,builds a chemisorbed coordination layer in the inner plane,and modulates local interfacial chemistry with spatial precision.This dualregion regulation collectively suppresses water reactivity,facilitates Zn^(2+)desolvation,and drives crystallo-graphically preferred deposition along the(101)plane,promoting lateral growth and mitigating dendrite for-mation.As a result,symmetric Zn||Zn cells exhibit over 4200 h of stable cycling at 1 mA cm^(-2) and maintain 1100 h of operation at 2 mA cm^(-2),even at 0℃.Zn||Ti half-cells achieve a Coulombic efficiency of 99.83%,while Zn||NH_(4)V_(4)O_(10) full cells deliver 93.92%capacity retention after 400 cycles at 2 A g^(-1),and preserve 85.3%after 300 cycles at 0℃.This work demonstrates a scalable,mechanism-driven electrolyte design paradigm for dendrite-free and high-performance aqueous Zn metal batteries. 展开更多
关键词 Aqueous zinc-ion batteries Helmholtz plane engineering Dendrite suppression Solvation modulation Facet-selective Zn deposition
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Periodontitis-associated salivary microbiota exacerbates systemic osteoclastogenesis via gut modulation and tryptophan metabolism suppression in ovariectomized mice
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作者 Nannan Wang Jun Qian +7 位作者 Min Wang Lili Li Wenzheng Liao Rixin Chen Hua Nie Ruiyang Ge Fangfang Sun Fuhua Yan 《International Journal of Oral Science》 2026年第1期152-164,共13页
Epidemiological studies have highlighted an association between periodontitis and osteoporosis.However,the mechanism underlining this association remains unclear.Here,we revealed significant differences in the salivar... Epidemiological studies have highlighted an association between periodontitis and osteoporosis.However,the mechanism underlining this association remains unclear.Here,we revealed significant differences in the salivary microbiota between periodontally healthy individuals and periodontitis patients,with periodontitis patients exhibiting increased salivary microbiota diversity and an elevated abundance of pathogenic bacteria.Using an ovariectomized(OVX) mouse model,we demonstrated that the salivary microbiota from periodontitis patients exacerbated bone destruction by modulating the gut microbiota.Metabolomic analysis revealed that the periodontitis-associated salivary microbiota suppressed tryptophan metabolism.The tryptophan metabolite indole-3-lactic acid(ILA) directly inhibited osteoclast formation and differentiation.In OVX mice treated with periodontitis salivary microbiota,supplementation with ILA effectively suppressed osteoclastogenesis and alleviated the detrimental effects of periodontitis-associated salivary microbiota on systemic bones.In summary,our data demonstrate that periodontitis can affect systemic bone metabolism via the oral-gut axis and that ILA supplementation serves as a potential therapeutic option to mitigate these adverse effects. 展开更多
关键词 tryptophan metabolism salivary microbiota PERIODONTITIS OSTEOCLASTOGENESIS pathogenic bacteriausing epidemiological studies indole lactic acid gut modulation
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Complexity-Reduced Equalization for 200 Gbit/s PON Downstream Systems Based on SSB Modulation and Direct Detection
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作者 Yang Tao Huang Xingang +3 位作者 Ma Zhuang Zhong Yiming Huang Xiatao Liu Bo 《ZTE Communications》 2026年第1期56-64,共9页
The 200 Gbit/s passive optical network(PON)is most likely to be the next-generation scheme following 50G PON.The costeffective direct detection(DD)system is the economical choice.However,larger-capacity DD systems wil... The 200 Gbit/s passive optical network(PON)is most likely to be the next-generation scheme following 50G PON.The costeffective direct detection(DD)system is the economical choice.However,larger-capacity DD systems will face much more serious power fading caused by chromatic dispersion(CD)combined with square-law DD and thereby significantly increases the complexity of equalization algorithms.In this paper,a 200 Gbit/s Nyquist 4-level pulse amplitude modulation(PAM4)single side-band(SSB)modulation-DD downlink scheme is designed,and a low complexity quadratic-nonlinear equalizer is proposed for this system.The computational complexity of the quadratic nonlinear equalizer is about 28%of that of the conventional Volterra nonlinear equalizer,while still exhibiting excellent nonlinear equalization ability.Simulation results for the 200 Gbit/s system with 20 km fiber transmission show that it can achieve a power budget of 29 dB,while a 30.4 dB power budget is obtained in the 50 Gbit/s experimental transmission. 展开更多
关键词 200 Gbit/s passive optical network single side band modulation direct detection EQUALIZATION
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Modulation of mitochondrial dysfunction:Mechanisms and strategies for the use of natural products to treat stroke
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作者 Na Qin Rujuan Liu +3 位作者 Rong Deng Liuliu Shi Lei Wang Ting Zhu 《Neural Regeneration Research》 2026年第6期2215-2226,共12页
Modulations of mitochondrial dysfunction,which involve a series of dynamic processes such as mitochondrial biogenesis,mitochondrial fusion and fission,mitochondrial transport,mitochondrial autophagy,mitochondrial apop... Modulations of mitochondrial dysfunction,which involve a series of dynamic processes such as mitochondrial biogenesis,mitochondrial fusion and fission,mitochondrial transport,mitochondrial autophagy,mitochondrial apoptosis,and oxidative stress,play an important role in the onset and progression of stroke.With a better understanding of the critical role of mitochondrial dysfunction modulations in post-stroke neurological injury,these modulations have emerged as a potential target for stroke prevention and treatment.Additionally,since effective treatments for stroke are extremely limited and natural products currently offer some outstanding advantages,we focused on the findings and mechanisms of action related to the use of natural products for targeting mitochondrial dysfunction in the treatment of stroke.Natural products achieve neuroprotective through multi-target regulation of mitochondrial dysfunction encompassing the following processes:(1)Mitochondrial biogenesis:Cordyceps and hydroxysafflor yellow A activate the peroxisome proliferator-activated receptor gamma coactivator 1-alpha/nuclear respiratory factor pathway,promote mitochondrial DNA replication and respiratory chain protein synthesis,and thereby restore energy supply in the ischemic penumbra.(2)Mitochondrial dynamics balance:Ginsenoside Rb3 promotes Opa1-mediated neural stem cell migration and diffusion for recovery of damaged brain tissue.(3)Mitochondrial autophagy:Gypenoside XVII selectively eliminates damaged mitochondria via the phosphatase and tensin homolog-induced kinase 1/Parkin pathway and blocks reactive oxygen species and the NOD-like receptor protein 3 inflammasome cascade,thereby alleviating blood-brain barrier damage.(4)Anti-apoptotic mechanisms:Ginkgolide K inhibits Bax mitochondrial translocation and downregulates caspase-3/9 activity,reducing neuronal programmed death induced by ischemia-reperfusion.(5)Oxidative stress regulation:Scutellarin exerts antioxidant properties and improves neurological function by modulating the extracellular signal-regulated kinase 5-Kruppel-like factor 2-endothelial nitric oxide synthase signaling pathway.(6)Intercellular mitochondrial transport:Neuroprotective effects of Chrysophanol are associated with accelerated mitochondrial transfer from astrocytes to neurons.Existing studies have confirmed that natural products exhibit neuroprotective effects through multidimensional interventions targeting mitochondrial dysfunction in both ischemic and hemorrhagic stroke models.However,their clinical translation still faces challenges,such as the difficulty in standardization due to component complexity,insufficient cross-regional clinical data,and the lack of long-term safety evaluations.Future research should aim to integrate new technologies,such as single-cell sequencing and organoid models,to deeply explore the mitochondria-targeting mechanisms of natural products and validate their efficacy through multicenter clinical trials,providing theoretical support and translational pathways for the development of novel anti-stroke drugs. 展开更多
关键词 apoptosis AUTOPHAGY hemorrhagic stroke ischemic stroke mitochondrial biogenesis mitochondrial dynamics mitochondrial dysfunction modulations mitochondrial transport natural products oxidative stress
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Artificial Cooper-Pair Density Modulation in Buckled Heterostructure
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作者 Zhongrui Wang Yingbo Wang +10 位作者 Xiangjia Bai Lu Cao Yucheng Xue Yang Cao Dawei Zhai Hong-Jun Gao Francois M.Peeters Bert Jorissen Lucian Covaci Yuhang Jiang Jinhai Mao 《Chinese Physics Letters》 2026年第3期147-176,共30页
erized by a periodic real-space modulation of the superconducting pairing order parameter,is a novel quantum phase observed in superconducting(SC)systems.It is believed to play a key role in understanding the pseudoga... erized by a periodic real-space modulation of the superconducting pairing order parameter,is a novel quantum phase observed in superconducting(SC)systems.It is believed to play a key role in understanding the pseudogap phase of superconductors and has recently been discovered in bulk cuprates,transition-metal dichalcogenide,and other unconventional superconductors.However,artificially engineered PDW in designable two-dimensional materials remain rare.In this paper,we report a strain-assisted strategy to realize cooper-pair density modulation in a van der Waals heterostructure:graphene on SC 2H-NbSe2.Superconductivity is induced in graphene via the proximity effect.Meanwhile,the graphene membrane spontaneously buckles into a periodic structure owing to strain,featuring a spatially modulated local density of states(LDOS).The interplay between the spatially modulated LDOS and the proximity-induced superconductivity results in an oscillatory pair density determined by the buckled geometry,constituting an artificial PDW.This approach enables the engineering of PDWs with periodicities of up to tens of nanometers and allows their realization in a variety of heterostructures with tailored designs.Our work provides new insights into the investigation of PDW physics using predesigned two-dimensional materials. 展开更多
关键词 strain assisted strategy graphene proximity effect quantum phase artificial Cooper pair density modulation van der waals heterostructure pseudogap phase bulk cupratestransition metal
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Magnetic-Field Modulation of Na_(3)V_(2)(PO_(4))_(3)Crystal Orientation for Enhanced Sodium-Ion Battery Performance
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作者 Pengcheng Wang Xuqi Lin +6 位作者 Houlin Cheng Ciqi Yuan Yongping Zheng Yingbin Lin Zhigao Huang Hao Chen Jiaxin Li 《Carbon Energy》 2026年第2期221-235,共15页
Na_(3)V_(2)(PO_(4))_(3)(NVP)is a promising electrode material that exhibits magnetic anisotropy;however,the potential of this magnetic anisotropy to optimize battery performance has been largely unexplored.This study ... Na_(3)V_(2)(PO_(4))_(3)(NVP)is a promising electrode material that exhibits magnetic anisotropy;however,the potential of this magnetic anisotropy to optimize battery performance has been largely unexplored.This study proposes a cost-effective and efficient method to induce the alignment of NVP along the(113)crystal plane by applying a vertical magnetic field during the slurry coating process,thereby enhancing its battery performance.Comprehensive structural characterizations and theoretical analysis elucidate the structure-activity relationship between the preferred crystal orientation and ion transport kinetics,facilitating the formation of more ordered Na+deintercalation pathways in NVP electrodes.This alignment reduces electrode tortuosity,enhances interfacial compatibility,and substantially improves battery performance,particularly in terms of high-rate cycling capability.As a result,the magnetic-field-modulated NVP(NVP-M⊥)electrode exhibits a high capacity retention of85.1%after 500 cycles at 5 C,significantly surpassing that of the pristine electrode.The NVP-M⊥electrode also demonstrates considerable reversible capacity at 40 C and maintains excellent stability under high temperature and prolonged cycling conditions.Furthermore,superior battery performance is observed in the assembled NVP-M⊥‖hard-carbon pouch cell and commercial NVP electrode following magnetic-field modulation,thereby validating the efficacy of this method.Consequently,this magnetic-field-induced crystal-orientation optimization strategy provides an innovative approach for low-cost and highthroughput preparation of high-performance sodium-ion batteries. 展开更多
关键词 battery performance magnetic‐field modulation Na_(3)V_(2)(PO_(4))_(3)cathode sodium‐ion batteries thermalsafety
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HF-LPME-HPLC-QAMS测定薄荷中黄酮类成分含量 被引量:1
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作者 金绍娣 顾东雅 +1 位作者 裴丽 顾晨露 《化学研究与应用》 北大核心 2025年第8期2422-2429,共8页
建立中空纤维液相微萃取联合高效液相色谱一测多评(HF-LPME-HPLC-QAMS)测定薄荷中7种黄酮类成分(芦丁、橙皮苷、香叶木苷、香蜂草苷、蒙花苷、刺槐素、香叶木素)的方法。通过单因素实验考察了萃取剂种类、样品相pH、搅拌速度、盐离子浓... 建立中空纤维液相微萃取联合高效液相色谱一测多评(HF-LPME-HPLC-QAMS)测定薄荷中7种黄酮类成分(芦丁、橙皮苷、香叶木苷、香蜂草苷、蒙花苷、刺槐素、香叶木素)的方法。通过单因素实验考察了萃取剂种类、样品相pH、搅拌速度、盐离子浓度、时间对微萃取操作的影响,确定以正辛醇为萃取溶剂、样品溶液pH为4.0,在1000 r/min下搅拌萃取90 min,得到的7种黄酮类成分富集显著、峰型好、干扰少。以橙皮苷为内参物,建立高效液相色谱一测多评测定其他6种黄酮类成分的计算方法并验证了该方法的准确性与可行性。通过不同的仪器、色谱柱、流速等因素考察了相对校正因子的耐受性,结果表明各组分所建立的相对校正因子重现性良好,且一测多评法计算值与外标法实测值无显著差异。该方法绿色高效、成本低、灵敏度高,可用于薄荷中7种黄酮类成分的纯化、分析。 展开更多
关键词 中空纤维液相微萃取 一测多评 薄荷 黄酮类成分
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一种星座模板匹配的MQAM调制盲识别方法
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作者 韩勋 郑佳 +2 位作者 冯鑫 匡银 文伟 《电子测量技术》 北大核心 2025年第11期123-130,共8页
针对现有聚类识别算法对先验参数敏感的问题,该文提出了一种基于模板匹配的MQAM调制盲识别方法。首先对载频、带宽及码速率进行估计,根据估计结果完成下变频、抽取等预处理;然后定义星座分布熵特征描述星座图分布的收敛度,并通过最优化... 针对现有聚类识别算法对先验参数敏感的问题,该文提出了一种基于模板匹配的MQAM调制盲识别方法。首先对载频、带宽及码速率进行估计,根据估计结果完成下变频、抽取等预处理;然后定义星座分布熵特征描述星座图分布的收敛度,并通过最优化星座分布熵的方式实现最佳判决时刻序列获取及剩余载波补偿,进而恢复出最优星座图分布;最后计算最优星座图分布与不同调制类型预设模板之间的匹配度,完成调制样式的识别,可识别样式包括16QAM、32QAM、64QAM、128QAM及256QAM。该方法对初始参数选择不敏感,且利用了星座图整体分布这一本质差异进行识别,稳定性高,适用于工程实现。仿真结果表明,当信噪比15 dB时各信号识别率高于93%,同时抗噪声能力较现有算法亦有明显提升,证明了所提方法的有效性。 展开更多
关键词 qam信号 调制样式识别 星座分布熵 模板匹配
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Optimization of Mapping Rule of Bit-Interleaved Turbo Coded Modulation with 16QAM 被引量:1
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作者 费泽松 杨宇 +1 位作者 刘林南 匡镜明 《Journal of Beijing Institute of Technology》 EI CAS 2005年第1期18-21,共4页
Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding perfor... Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding performance. Furthermore, bit-interleaved in-phase and quadrature phase (I-Q) Turbo coded modulation scheme are designed similarly with I-Q trellis coded modulation (TCM). Through performance evaluation and analysis, it can be seen that the novel mapping rule outperforms traditional one and the I-Q Turbo coded modulation can not achieve good performance as expected. Therefore, there is not obvious advantage in using I-Q method in bit-interleaved Turbo coded modulation. 展开更多
关键词 binary Turbo coded modulation quadrature amplitude modulation (qam) mapping rule in-phase and quadrature (I-Q) coded modulation
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HPLC-QAMS法同时测定灵丹片中川芎5种成分的含量
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作者 陈斐斐 余欢 库雄 《湖北中医药大学学报》 2025年第4期44-48,共5页
目的 采用高效液相色谱-多指标质量评价法(HPLC-QAMS)对灵丹片中的川芎嗪,阿魏酸,川芎三萜,欧当归内酯A,藁本内酯的含量。方法 利用Dionex-U3000高效液相色谱系统,配备HPLCone-C_(18)色谱柱(4.6 mm×250 mm,5μm),并以MeCN为溶剂A,... 目的 采用高效液相色谱-多指标质量评价法(HPLC-QAMS)对灵丹片中的川芎嗪,阿魏酸,川芎三萜,欧当归内酯A,藁本内酯的含量。方法 利用Dionex-U3000高效液相色谱系统,配备HPLCone-C_(18)色谱柱(4.6 mm×250 mm,5μm),并以MeCN为溶剂A,H2O为溶剂B的混合溶液作为流动相。实施梯度洗脱程序,具体为:0~60 min,A:10%→100%;60~90 min,100%溶剂A;90~96 min,A:10%-→100%。流速V=11mL/min;柱温T=25℃。检测器的波长设定为210nm。结果 川芎嗪,阿魏酸,川芎三萜,欧当归内酯A,藁本内酯分别在1.42~39.22、1.27~40.13、2.13~50.63、2.02~46.47、1.64~44.3 1Lμg/mL显示出良好的线性相关性(r≥0.9993),平均加样回收率(RSD)分别为0.9994、0.9996、0.9994、0.9995、0.9991。结论 采用一测多评法得到的数据与使用外标法得到的结果相比较,两者之间未观察到显著差异,可用于同时测定灵丹片主要成分川芎所含的川芎嗪,阿魏酸,川芎三萜,欧当归内酯A,藁本内酯含量,为评估灵丹片的质量提供了科学依据。 展开更多
关键词 灵丹片 含量测定 HPLC-qamS 质量评价 川芎
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九味熄风颗粒UPLC-Q-TOF-MS/MS定性分析及HPLC-QAMS酚类成分定量分析 被引量:1
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作者 黄丽姣 王佳 +3 位作者 康雨 胡军华 韩明书 王振中 《药物评价研究》 北大核心 2025年第5期1245-1256,共12页
目的采用UPLC-Q-TOF-MS/MS技术解析九味熄风颗粒化学成分并建立5种酚酸类成分(天麻素、巴利森苷E、巴利森苷B、巴利森苷C、巴利森苷A)一测多评(QAMS)定量测定方法。方法应用Waters UPLC HSS T3色谱柱,以甲醇-0.1%甲酸水为流动相洗脱梯度... 目的采用UPLC-Q-TOF-MS/MS技术解析九味熄风颗粒化学成分并建立5种酚酸类成分(天麻素、巴利森苷E、巴利森苷B、巴利森苷C、巴利森苷A)一测多评(QAMS)定量测定方法。方法应用Waters UPLC HSS T3色谱柱,以甲醇-0.1%甲酸水为流动相洗脱梯度,体积流量0.3 mL·min^(-1),柱温35℃,采用电喷雾离子源(ESI),正、负离子模式扫描,根据质谱数据结合文献报道进行成分鉴定。采用Phenomenex Luna C18色谱柱,乙腈-0.1%磷酸水为流动相梯度洗脱,体积流量1.0 mL·min^(-1),柱温30℃,检测波长220 nm,以天麻素为内参物,建立其与4种酚类成分的相对校正因子,计算各待测组分的含量,比较外标法(ESM)和QAMS这2种方法的差异。结果从九味熄风颗粒中共推断和鉴定出92个化学成分,包括20个生物碱类、20个有机酸及其酯类、12个环烯醚萜类、6个酚类、6个氨基酸类、6个苯乙醇苷类、6个三萜类及16个其他类(糖类、黄酮类、核苷类等)成分。QAMS法和ESM法测得的各成分含量无显著性差异,5种成分相对误差(RE)均低于5%。结论通过UPLC-Q-TOF-MS/MS技术可实现对九味熄风颗粒化学成分的快速鉴定,建立的ESM与QAMS法联用的多指标定量方法可为该制剂酚类成分的质量一致性评价提供技术支撑。 展开更多
关键词 九味熄风颗粒 UPLC-Q-TOF-MS/MS 外标法(ESM) 一测多评(qamS)法 天麻素 巴利森苷E 巴利森苷B 巴利森苷C 巴利森苷A
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