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Special Issue on Using Artificial Intelligence in Internet of Things vip Editors: Fuji Ren, Yu Gu
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作者 Fuji Ren yu gu 《ZTE Communications》 2014年第4期2-2,共1页
Interact of Things has received much attention over the past de cade. With the rapid increase in the use of smart devices, we are now able to collect big data on a daily basis. The data we are gather ing and related p... Interact of Things has received much attention over the past de cade. With the rapid increase in the use of smart devices, we are now able to collect big data on a daily basis. The data we are gather ing and related problems arc becoming more complex and uncer tain. Researchers have therefore turned to AI as an efficient way of dealing with the problems created by big data. 展开更多
关键词 AI ZTE Communications Call for Papers Special Issue on Using Artificial Intelligence in Internet of Things
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Regulatory Effects of Radix Salviae Miltiorrhizae Water Extract and Semen Ziziphi Spinosae Compound onβ-secretase Activity in Mice Exposed to Aluminum Maltolate
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作者 Jiaguo LIANG Min WEI +7 位作者 yuxue HUANG yu gu Jinmiao WU Kun CHEN Yongqiu QIU yuncong LU Junchen WEI Shuqiu ZHANG 《Medicinal Plant》 2025年第4期39-42,共4页
[Objectives]To explore the effects of Radix Salviae Miltiorrhizae water extract and Semen Ziziphi Spinosae compound on theβ-secretase activity in mice exposed to aluminum maltolate.[Methods]A total of 60 healthy,clea... [Objectives]To explore the effects of Radix Salviae Miltiorrhizae water extract and Semen Ziziphi Spinosae compound on theβ-secretase activity in mice exposed to aluminum maltolate.[Methods]A total of 60 healthy,clean-grade SPF mice were randomly assigned to four groups based on their body weight,with each group consisting of 15 mice.The groups included a control group,a model group,treatment group 1,and treatment group 2.The control group received an equivalent dose of normal saline,while the model group and treatment groups 1 and 2 were intraperitoneally injected with 0.3 mg/kg of aluminum maltolate solution for 60 d.Additionally,treatment groups 1 and 2 were injected with 0.3 mg/kg of Radix Salviae Miltiorrhizae water extract and 0.3 mg/kg of Semen Ziziphi Spinosae compound,respectively,starting from the 31 st day for a total of 30 d.The cognitive functions of mice,specifically their learning and memory capabilities,were assessed using the Y-shaped water maze test at three distinct time points:prior to,during,and following the experimental procedure.Serum samples were collected for the analysis of various biochemical markers,including hemoglobin(Hb),total cholesterol(TC),triglycerides(TG),total protein(TP),alanine aminotransferase(ALT),and blood urea nitrogen(BUN).Additionally,brain tissues were harvested to evaluate the levels of glutathione peroxidase(GSH-PX)and acetylcholinesterase(AChE)in both serum and brain samples.The expression levels ofα-secretase,β-secretase,andγ-secretase in mouse serum were quantified using enzyme-linked immunosorbent assay(ELISA).[Results]According to the final results of the Y-shaped water maze test,the administration of therapeutic drugs to mice resulted in a gradual reduction in both the swimming time and the distance traveled to reach the platform in treatment groups 1 and 2.Additionally,the number of errors made by these treatment groups was significantly greater than that observed in the control group,with statistically significant differences(P<0.01).Among the three groups subjected to subchronic aluminum exposure,statistically significant differences were observed in the levels of Hb,TC,TG,TP,ALT,BUN,brain GSH-PX,and brain AChE(P<0.05).Furthermore,with the increasing duration of therapeutic drug administration,the levels ofβ-secretase in the brains of mice in both the treatment groups and the model group exhibited a significant decrease,while the levels ofα-secretase showed a significant increase.Additionally,the differences were statistically significant when compared to the control group(P<0.05).[Conclusions]Radix Salviae Miltiorrhizae water extract and Semen Ziziphi Spinosae compound will decrease the expression level ofβ-secretase activity in mice exposed to aluminum maltolate. 展开更多
关键词 Radix Salviae Miltiorrhizae water extract Semen Ziziphi Spinosae compound ALUMINUM Β-SECRETASE MICE Learning and memory capability
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Lactate and lactylation modifications in neurological disorders
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作者 yu gu Keyang Chen +5 位作者 Chunyan Lei Xinglong Yang Lu Wang Linhu Zhao Wen Jiang Qionghua Deng 《Neural Regeneration Research》 2026年第5期1681-1697,共17页
Research into lactylation modifications across various target organs in both health and disease has gained significant attention.Many essential life processes and the onset of diseases are not only related to protein ... Research into lactylation modifications across various target organs in both health and disease has gained significant attention.Many essential life processes and the onset of diseases are not only related to protein abundance but are also primarily regulated by various post-translational protein modifications.Lactate,once considered merely a byproduct of anaerobic metabolism,has emerged as a crucial energy substrate and signaling molecule involved in both physiological and pathological processes within the nervous system.Furthermore,recent studies have emphasized the significant role of lactate in numerous neurological diseases,including Alzheimer's disease,Parkinson's disease,acute cerebral ischemic stroke,multiple sclerosis,Huntington's disease,and myasthenia gravis.The purpose of this review is to synthesize the current research on lactate and lactylation modifications in neurological diseases,aiming to clarify their mechanisms of action and identify potential therapeutic targets.As such,this work provides an overview of the metabolic regulatory roles of lactate in various disorders,emphasizing its involvement in the regulation of brain function.Additionally,the specific mechanisms of brain lactate metabolism are discussed,suggesting the unique roles of lactate in modulating brain function.As a critical aspect of lactate function,lactylation modifications,including both histone and non-histone lactylation,are explored,with an emphasis on recent advancements in identifying the key regulatory enzymes of such modifications,such as lactylation writers and erasers.The effects and specific mechanisms of abnormal lactate metabolism in diverse neurological diseases are summarized,revealing that lactate acts as a signaling molecule in the regulation of brain functions and that abnormal lactate metabolism is implicated in the progression of various neurological disorders.Future research should focus on further elucidating the molecular mechanisms underlying lactate and lactylation modifications and exploring their potential as therapeutic targets for neurological diseases. 展开更多
关键词 astrocyte-neuron lactate shuttle theory brain functions brain lactate metabolism central nervous system histone lysine lactylation monocarboxylate transporters nervous system neurodegenerative diseases non-histone lysine lactylation post-translational modifications
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LogUAD: Log Unsupervised Anomaly Detection Based on Word2Vec 被引量:5
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作者 Jin Wang Changqing Zhao +3 位作者 Shiming He yu gu Osama Alfarraj Ahed Abugabah 《Computer Systems Science & Engineering》 SCIE EI 2022年第6期1207-1222,共16页
System logs record detailed information about system operation and areimportant for analyzing the system's operational status and performance. Rapidand accurate detection of system anomalies is of great significan... System logs record detailed information about system operation and areimportant for analyzing the system's operational status and performance. Rapidand accurate detection of system anomalies is of great significance to ensure system stability. However, large-scale distributed systems are becoming more andmore complex, and the number of system logs gradually increases, which bringschallenges to analyze system logs. Some recent studies show that logs can beunstable due to the evolution of log statements and noise introduced by log collection and parsing. Moreover, deep learning-based detection methods take a longtime to train models. Therefore, to reduce the computational cost and avoid loginstability we propose a new Word2Vec-based log unsupervised anomaly detection method (LogUAD). LogUAD does not require a log parsing step and takesoriginal log messages as input to avoid the noise. LogUAD uses Word2Vec togenerate word vectors and generates weighted log sequence feature vectors withTF-IDF to handle the evolution of log statements. At last, a computationally effi-cient unsupervised clustering is exploited to detect the anomaly. We conductedextensive experiments on the public dataset from Blue Gene/L (BGL). Experimental results show that the F1-score of LogUAD can be improved by 67.25%compared to LogCluster. 展开更多
关键词 Log anomaly detection log instability word2Vec feature extraction
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Spin regulation on(Co,Ni)Se_(2)/C@FeOOH hollow nanocage accelerates water oxidation
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作者 yu gu Xiaolei Wang +7 位作者 Muhammad Humayun Linfeng Li Huachuan Sun Xuefei Xu Xinying Xue Aziz Habibi‐Yangjeh Kristiaan Temst Chundong Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第3期839-850,共12页
Spin engineering is recognized as a promising strategy that modulates the association between d‐orbital electrons and the oxygenated species,and enhances the catalytic kinetics.However,few efforts have been made to c... Spin engineering is recognized as a promising strategy that modulates the association between d‐orbital electrons and the oxygenated species,and enhances the catalytic kinetics.However,few efforts have been made to clarify whether spin engineering could make a considerable enhancement for electrocatalytic water oxidation.Herein,we report the spin engineering of a nanocage‐structured(Co,Ni)Se_(2)/C@FeOOH,that showed significant oxygen evolution reaction(OER)activity.Magnetization measurement presented that the(Co,Ni)Se_(2)/C@FeOOH sample possesses higher polarization spin number(μb=6.966μB/f.u.)compared with that of the(Co,Ni)Se_(2)/C sample(μb=6.398μB/f.u.),for which the enlarged spin polarization number favors the adsorption and desorption energy of the intermediate oxygenated species,as confirmed by surface valance band spectra.Consequently,the(Co,Ni)Se_(2)/C@FeOOH affords remarkable OER product with a low overpotential of 241 mV at a current of 10 mA cm^(-2) and small Tafel slope of 44 mV dec^(-1) in 1.0 mol/L KOH alkaline solution,significantly surpassing the parent(Co,Ni)Se_(2)/C catalyst.This work will trigger a solid step for the design of highly‐efficient OER electrocatalysts. 展开更多
关键词 Spin engineering d‐Orbital electron Hollownanocage FEOOH Oxygen evolution reaction
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Recent Advances in the Molecular Mechanisms of Ocular Dominance Plasticity in the Visual Cortex 被引量:2
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作者 Yanglin Qin Wei Wang +1 位作者 yu gu Xuefeng Shi 《Neuroscience Bulletin》 2025年第9期1645-1655,共11页
The visual cortex is an essential part of the brain for processing visual information.It exhibits structural and functional plasticity,which is crucial for adapting to complex visual environments.The quintessential ma... The visual cortex is an essential part of the brain for processing visual information.It exhibits structural and functional plasticity,which is crucial for adapting to complex visual environments.The quintessential manifestation of visual cortical plasticity is ocular dominance plasticity during the critical period,which involves numerous cellular and molecular events.While previous studies have emphasized the role of visual cortical neurons and their associated functional molecules in visual plasticity,recent findings have revealed that structural factors such as the extracellular matrix and glia are also involved.Investigating how these molecules interact to form a complex network that facilitates plasticity in the visual cortex is crucial to our understanding of the development of the visual system and the advancement of therapeutic strategies for visual disorders like amblyopia. 展开更多
关键词 Visual cortex PLASTICITY Visual experience Development Molecular mechanisms
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Inverting tidal velocity from geomagnetic satellite by nonlinear method 被引量:1
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作者 yu gu ZhengYong Ren +3 位作者 Yang Wu LiNan Xu PengFei Liu Keke Zhang 《Earth and Planetary Physics》 2025年第3期607-613,共7页
This study presents an inversion method to recover the tidal flow velocity using tidal signals extracted from geomagnetic satellite dataset.By integrating the latest Earth conductivity profile and the Earth's magn... This study presents an inversion method to recover the tidal flow velocity using tidal signals extracted from geomagnetic satellite dataset.By integrating the latest Earth conductivity profile and the Earth's magnetic field model,the limited memory quasi-Newton method(L-BFGS)is used to directly invert seawater flow velocities.We used the radial component of the induced magnetic field as the observed data,constructed an L_(2)-norm-based data misfit term using theoretical response and observed data,and applied smoothness constraints to the ocean flow velocity.The results agree well with the widely used HAMTIDE model in low-and mid-latitude regions,which is attributed to Macao Science Satellite-1's(MSS-1)unique low-inclination orbit of full coverage in these areas.These findings underscore MSS-1's potential to advance research on tidal-induced magnetic fields and their applications in ocean dynamics studies. 展开更多
关键词 Macao Science Satellite-1 satellite magnetic data tidal velocity inversion
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A Potentially Shared Neural Basis Linking Rapid Saccades and Avoidance Initiation in the Superior Colliculus Driven by Visual Threats
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作者 Zhou Sun yu gu 《Neuroscience Bulletin》 2025年第6期1115-1118,共4页
Throughout the lifespan,an animal can encounter predators frequently,thus the ability to avoid attacks from predators is crucial for its survival.The chances of evading danger can be greatly improved if the animal can... Throughout the lifespan,an animal can encounter predators frequently,thus the ability to avoid attacks from predators is crucial for its survival.The chances of evading danger can be greatly improved if the animal can respond immediately to the threat.Therefore,when an animal detects a threat through its visual system,it must quickly direct its gaze and attention toward the source of danger,assess the threat level,and take appropriate action. 展开更多
关键词 avoidance initiation threat assessment gaze direction survival visual systemit visual threats superior colliculus rapid saccades
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Rolling Bearing Fault Diagnosis Based on MTF Encoding and CBAM-LCNN Mechanism
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作者 Wei Liu Sen Liu +2 位作者 Yinchao He Jiaojiao Wang yu gu 《Computers, Materials & Continua》 2025年第3期4863-4880,共18页
To address the issues of slow diagnostic speed,low accuracy,and poor generalization performance in traditional rolling bearing fault diagnosis methods,we propose a rolling bearing fault diagnosis method based on Marko... To address the issues of slow diagnostic speed,low accuracy,and poor generalization performance in traditional rolling bearing fault diagnosis methods,we propose a rolling bearing fault diagnosis method based on Markov Transition Field(MTF)image encoding combined with a lightweight convolutional neural network that integrates a Convolutional Block Attention Module(CBAM-LCNN).Specifically,we first use the Markov Transition Field to convert the original one-dimensional vibration signals of rolling bearings into two-dimensional images.Then,we construct a lightweight convolutional neural network incorporating the convolutional attention module(CBAM-LCNN).Finally,the two-dimensional images obtained from MTF mapping are fed into the CBAM-LCNN network for image feature extraction and fault diagnosis.We validate the effectiveness of the proposed method on the bearing fault datasets from Guangdong University of Petrochemical Technology’s multi-stage centrifugal fan and Case Western Reserve University.Experimental results show that,compared to other advanced baseline methods,the proposed rolling bearing fault diagnosis method offers faster diagnostic speed and higher diagnostic accuracy.In addition,we conducted experiments on the Xi’an Jiaotong University rolling bearing dataset,achieving excellent results in bearing fault diagnosis.These results validate the strong generalization performance of the proposed method.The method presented in this paper not only effectively diagnoses faults in rolling bearings but also serves as a reference for fault diagnosis in other equipment. 展开更多
关键词 Rolling bearing fault diagnosis markov transition field lightweight convolutional neural network convolutional block attention module
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Comprehensive research facility for negative ion source neutral beam injection at CRAFT:design and first
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作者 Jianglong WEI Yahong XIE +40 位作者 yuanlai XIE Caichao JIANG yuanzhe ZHAO Yongjian XU yuming gu Wei YI Wei LIU Lyuyang BU Dezhi YAN Zhimin LIU Sheng LIU Junjun PAN Shiyong CHEN Ling yu Qinglong CUI Shihua SONG yuqing CHEN Ji WANG Ling LIU Shengmin PAN Bin guO Zhigang ZHU Na WANG Junwei XIE yuwen YANG Tengsai ZHU Lixin YANG yufan LI Ning TANG Qianxu WANG Huihui HONG Bo LIU yuqian LI Yang LI yu gu Xufeng PENG Shanhu LIU Yong WU Xiancai MENG Chundong HU Lizhen LIANG 《Plasma Science and Technology》 2025年第4期1-11,共11页
Neutral beam injection(NBI)has been proven as a reliable heating and current drive method for fusion plasma.For the high-energy NBI system(particle energy>150 ke V)of large-scale fusion devices,the negative ion sou... Neutral beam injection(NBI)has been proven as a reliable heating and current drive method for fusion plasma.For the high-energy NBI system(particle energy>150 ke V)of large-scale fusion devices,the negative ion source neutral beam injection(NNBI)system is inevitable,which can obtain an acceptable neutralization efficiency(>55%).But the NNBI system is very complex and challengeable.To explore and master the key NNBI technology for future fusion reactor in China,an NNBI test facility is under development in the framework of the Comprehensive Research Facility for Fusion Technology(CRAFT).The initial goal of CRAFT NNBI facility is to achieve a 2 MW hydrogen neutral beam at the energy of 200–400 ke V for lasting 100 s.In the first operation of the CRAFT NNBI facility,a negative ion source with dual RF drivers was developed and tested.By using the 50 keV accelerator,the long-pulse and highcurrent extractions of negative hydrogen ions have been achieved and the typical values were 55.4 keV,7.3 A(~123 A/m^(2)),105 s and 55.0 keV,14.7 A(~248 A/m^(2)),30 s,respectively.By using the 200 keV accelerator,the megawatt-class negative hydrogen beam has also been achieved(135.9 keV,8.9 A,8 s).The whole process of the gas neutralization of negative ion beam,electric removal of residual ions,and beam transport have been demonstrated experimentally. 展开更多
关键词 beam acceleration magnetic confinement fusion negative ion source neutral beam injection(Some figures may appear in colour only in the online journal)
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Analysis of Meteorological Conditions for a Sea Fog Process in 2016 被引量:3
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作者 Xiaomeng Shi Xueying Liu +1 位作者 yu gu Qian Wang 《Atmospheric and Climate Sciences》 2021年第3期419-425,共7页
The visibility characteristics and meteorological conditions of a sea fog process on 27</span><sup><span style="font-family:Verdana;">th</span></sup><span style="font-fa... The visibility characteristics and meteorological conditions of a sea fog process on 27</span><sup><span style="font-family:Verdana;">th</span></sup><span style="font-family:Verdana;"> February, 2016 are analyzed and the heavy fog process is simulated by the Weather Research and Forecasting (WRF) model in this paper. The forecast results show that the visibility in Qingdao coastal area is light fog on the night of the 26</span><sup><span style="font-family:Verdana;">th</span></sup><span style="font-family:Verdana;">. In the WRF simulation, it can be observed from the sea-level pressure that the wind direction of Qingdao and the coastal area turned southerly with the eastward movement of the low pressure system on surface from 1200 UTC to 1800 UTC on the 26</span><sup><span style="font-family:Verdana;">th</span></sup><span style="font-family:Verdana;">. A large amount of water vapor brought by easterly and southerly wind provides sufficient water vapor conditions for the formation and development of the sea fog. At 975 hPa, there is a strong warm tongue over Shandong Peninsula at 0600 UTC on the 26</span><sup><span style="font-family:Verdana;">th</span></sup><span style="font-family:Verdana;">, w</span><span><span style="font-family:Verdana;">hile the offshore is affected by the cold tongue, where the horizontal temperature gradient is large and there is a strong baroclinicity. At 850 hPa, there is a weak warm ridge over Qingdao at 1200 UTC on the 26</span><sup><span style="font-family:Verdana;">th</span></sup><span style="font-family:Verdana;">, which means that it is an inversion layer, which is conducive to the maintenance of fog. 展开更多
关键词 Qingdao Offshore Heavy Fog WRF Satellite Remote Sensing DUAL-CHANNEL
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Terahertz Metamaterial-Based Microbolometers Fabricated by Conventional MEMS 被引量:1
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作者 Tianhong Ao Xiangdong Xu +6 位作者 yu gu Zhegeng Chen Yadong Jiang Xinrong Li yuxiang Lian Fu Wang Qiong He 《Optics and Photonics Journal》 2016年第8期215-218,共4页
37 μm × 37 μm array of metamaterial-based microbolometers was designed and successfully fa-bricated by conventional MEMS technology. FTIR measurements reveal that the as-designed mi-crobolometers exhibit a high... 37 μm × 37 μm array of metamaterial-based microbolometers was designed and successfully fa-bricated by conventional MEMS technology. FTIR measurements reveal that the as-designed mi-crobolometers exhibit a high absorption of ~31.5% at 3.93 THz. In contrast, no response can be detected from those microbolometers without metamaterials. The experimental results have been confirmed by simulations. 展开更多
关键词 METAMATERIAL ABSORBER MEMS THZ
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碳酸酯类电解液中纳米银电极界面过程的原位拉曼光谱研究 被引量:2
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作者 谷宇 胡元飞 +7 位作者 王卫伟 尤恩铭 唐帅 苏建加 易骏 颜佳伟 田中群 毛秉伟 《电化学(中英文)》 CAS 北大核心 2023年第12期14-23,共10页
锂电池体系中负极表面固态电解质界面相(SEI)对锂电池性能起到至关重要的作用。然而,SEI结构和化学组成复杂,其形成机理至今仍未完全阐明,阻碍了锂电池的发展和应用。本文从方法学角度出发,采用表面增强拉曼光谱(SERS)“借力”策略,通... 锂电池体系中负极表面固态电解质界面相(SEI)对锂电池性能起到至关重要的作用。然而,SEI结构和化学组成复杂,其形成机理至今仍未完全阐明,阻碍了锂电池的发展和应用。本文从方法学角度出发,采用表面增强拉曼光谱(SERS)“借力”策略,通过优化银纳米粒子的结构并借助其外来表面局域等离激元共振作用,开展以EC-DMC为溶剂的碳酸酯类电解液体系中SEI成膜过程的原位研究。为了确保可靠的原位SERS测试,我们设计了一种三电极体系气密拉曼电池。我们利用原位SERS方法,在纳米银电极上获得了SEI成膜过程的组成和结构信息。研究表明,SEI随电位变化呈现出双层结构,其中内层由薄且致密的无机组分构成,外层由疏松的有机组分构成。同时,研究发现LEMC是EC还原的主要成分,而不是LEDC,且金属锂参与的化学反应在形成稳定SEI中的起到关键作用。此外,锂发生沉积后,由于锂与银的合金效应导致其介电常数发生变化,从而削无法进一步增强SEI的拉曼信号。本文为深入理解负极表面SEI的形成及演变过程提供依据,并为今后开展锂电池体系相关界面过程的原位研究提供借鉴。 展开更多
关键词 固态电解质界面相 原位SERS 负极界面 锂电池
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电极/碱性聚电解质界面的微分电容曲线和零电荷电位测定 被引量:1
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作者 刘晨希 邹泽萍 +11 位作者 胡梅雪 丁宇 谷宇 刘帅 南文静 马溢昌 陈招斌 詹东平 张秋根 庄林 颜佳伟 毛秉伟 《电化学(中英文)》 CAS 北大核心 2024年第3期24-33,共10页
碱性聚合物电解质作为现代碱性氢氧燃料电池的核心组成部分,其单离子导体的特性使得“电极/碱性聚电解质”界面的性质与“电极/溶液”界面有所不同。本文使用微电极,运用循环伏安、电化学交流阻抗以及浸入法等方法,测定了电极/碱性聚电... 碱性聚合物电解质作为现代碱性氢氧燃料电池的核心组成部分,其单离子导体的特性使得“电极/碱性聚电解质”界面的性质与“电极/溶液”界面有所不同。本文使用微电极,运用循环伏安、电化学交流阻抗以及浸入法等方法,测定了电极/碱性聚电解质界面的微分电容曲线和零电荷电位。该界面的微分电容曲线呈“U”状,且存在局域极小值,该极小值所对应的电位与浸入法测得的零电荷电位数值一致。单离子导体的特性使得“电极/碱性聚电解质”界面在零电荷电位两侧表现出不同的电化学极化行为。 展开更多
关键词 碱性物电解质 双电层 微电极 微分电容曲线 零电荷电位
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金属-水界面催化的分子机制:加氢与氧化反应 被引量:1
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作者 顾宇 王磊 +1 位作者 徐柏庆 施慧 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第11期1-55,共55页
固-水界面及相关现象(吸附、成核、腐蚀、催化等)存在于各类化学、物理和生物体系中.就多相催化的分子机制而言,长期以来主要的研究对象是固-气界面催化,对于催化剂与液体相接触时的固-液界面结构及固-液界面催化(尤其是催化动力学与机... 固-水界面及相关现象(吸附、成核、腐蚀、催化等)存在于各类化学、物理和生物体系中.就多相催化的分子机制而言,长期以来主要的研究对象是固-气界面催化,对于催化剂与液体相接触时的固-液界面结构及固-液界面催化(尤其是催化动力学与机理中的溶剂效应的本质)的理解则显著滞后.金属-水界面的催化加氢和氧化反应不仅在化学工业的绿色可持续发展中发挥着关键作用,也会对诸多生物体系的功能产生重要影响.然而,水所特有的理化性质使得固-水界面在催化过程中容易呈现丰富且复杂多变的特性,认识其中的微观机制具有挑战性.本文针对几类重要且典型的催化加氢和催化氧化反应(例如双氧水直接合成、生物质分子加氢脱氧、一氧化碳和醇类分子的氧化等),通过遴选近十年左右的代表性文献,总结并剖析了水分子(作为溶剂和添加剂)以及由水导致的溶解、表面基团电离、分子活化/钝化与解离等衍生形成的中性或离子化物种对表界面催化反应行为、机理和构效关系的影响方式与机制.这些实例共同揭示了氢键相互作用、表面基团的离子化、极性环境中化学键的异裂以及质子耦合电子转移等在调控金属-水界面的催化加氢和催化氧化反应中发挥着重要作用.在总结普遍规律和原理的基础上,还针对不同催化反应体系的特异性(例如除反应物外的界面共吸附物种与溶剂水和/或催化剂表面之间的相互作用对反应物分子的活泼性和反应机理的影响)进行了细致剖析.此外,越来越多的实验证据表明,金属-水界面的热催化加氢和热催化氧化与相应的电催化加氢和电催化氧化在反应机理等方面存在诸多相似性,预示着将两种长期分立的多相催化方法相结合,对多相催化反应中的金属-水界面进行系统深入的研究,有望更全面地理解金属-水界面催化的分子机制.本文的展望部分提出了一些亟待解决的重要科学问题和未来研究发展的核心任务,包括界面水分子和溶剂化物种的原位动态检测与结构解析、热催化加氢和热催化氧化反应的电化学本质等.这些研究目标的达成有赖于缜密的实验设计和准确严谨的(包括动力学同位素效应在内)测定与分析,以及先进的原位/工况表征技术和更完善的理论模拟方法的灵活应用. 展开更多
关键词 固-液界面 金属-水界面 氢键相互作用 质子耦合电子转移 水相反应 催化加氢 催化氧化
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Highly Efficient Adsorption of Copper Ions by a PVP-Reduced Graphene Oxide Based On a New Adsorptions Mechanism 被引量:10
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作者 Yongji Zhang HuiJuan Chi +4 位作者 WenHui Zhang Youyi Sun Qing Liang yu gu Riya Jing 《Nano-Micro Letters》 SCIE EI CAS 2014年第1期80-87,共8页
Polyvinylpyrrolidone-reduced graphene oxide was prepared by modified hummers method and was used as adsorbent for removing Cu ions from wastewater. The effects of contact time and ions concentration on adsorption capa... Polyvinylpyrrolidone-reduced graphene oxide was prepared by modified hummers method and was used as adsorbent for removing Cu ions from wastewater. The effects of contact time and ions concentration on adsorption capacity were examined. The maximum adsorption capacity of 1689 mg/g was observed at an initial p H value of 3.5 after agitating for 10 min. It was demonstrated that polyvinylpyrrolidone-reduced graphene oxide had a huge adsorption capacity for Cu ions, which was 10 times higher than maximal value reported in previous works. The adsorption mechanism was also discussed by density functional theory. It demonstrates that Cu ions are attracted to surface of reduced graphene oxide by C atoms in reduced graphene oxide modified by polyvinylpyrrolidone through physisorption processes, which may be responsible for the higher adsorption capacity. Our results suggest that polyvinylpyrrolidone-reduced graphene oxide is an effective adsorbent for removing Cu ions in wastewater. It also provides a new way to improve the adsorption capacity of reduced graphene oxide for dealing with the heavy metal ion in wastewater. 展开更多
关键词 POLYVINYLPYRROLIDONE Graphene oxide Cu ions Wastewater treatment Adsorption mechanism Density functional theory
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Development of a compact DOI-TOF detector module for high-performance PET systems 被引量:6
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作者 Qing-Yang Wei Tian-Peng Xu +4 位作者 Tian-Tian Dai Shi Wang Ya-Qiang Liu yu gu Tian-yu Ma 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第4期1-7,共7页
To increase spatial resolution and signal-to-noise ratio in PET imaging,we present in this paper the design and performance evaluation of a PET detector module combining both depth-of-interaction(DOI) and time-offligh... To increase spatial resolution and signal-to-noise ratio in PET imaging,we present in this paper the design and performance evaluation of a PET detector module combining both depth-of-interaction(DOI) and time-offlight(TOF) capabilities.The detector module consists of a staggered dual-layer LYSO block with2 mm × 2 mm × 7 mm crystals.MR-compatible SiPM sensors(MicroFJ-30035-TSV,SensL) are assembled into an 8× 8 array.SiPM signals from both fast and slow outputs are read out by a 128-channel ASIC chip.To test its performance,a flood histogram is acquired with a ^(22)Na point source on top of the detector,and the energy resolution and the coincidence resolving time(CRT) value for each individual crystal are measured.The flood histogram shows excellent crystal separation in both layers.The average energy resolution at 511 keV is 14.0 and 12.7%at the bottom and top layers,respectively.The average CRT of a single crystal is 635 and 565 ps at the bottom and top layers,respectively.In conclusion,the compact DOI-TOF PET detector module is of excellent crystal identification capability,good energy resolution and reasonable time resolution and has promising application prospective in clinical TOF PET,PET/MRI,and brain PET systems. 展开更多
关键词 POSITRON emission TOMOGRAPHY SIPM Depth of interaction (DOI) TIME-OF-FLIGHT (TOF)
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Functional Metabolomics Reveals that Astragalus Polysaccharides Improve Lipids Metabolism through Microbial Metabolite 2-Hydroxybutyric Acid in Obese Mice 被引量:9
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作者 Bingbing Li Ying Hong +7 位作者 yu gu Shengjie Ye Kaili Hu Jian Yao Kan Ding Aihua Zhao Wei Jia Houkai Li 《Engineering》 SCIE EI 2022年第2期111-122,共12页
Polysaccharides are widely present in herbs with multiple activities,especially immunity regulation and metabolic benefits for metabolic disorders.However,the underlying mechanisms are not well under-stood.Functional ... Polysaccharides are widely present in herbs with multiple activities,especially immunity regulation and metabolic benefits for metabolic disorders.However,the underlying mechanisms are not well under-stood.Functional metabolomics is increasingly used to investigate systemic effects on the host by iden-tifying metabolites with particular functions.This study explores the mechanisms underlying the metabolic benefits of Astragalus polysaccharides(APS)by adopting a functional metabolomics strategy.The effects of APS were determined in eight-week high-fat diet(HFD)-fed obese mice.Then,gas chromatography–time-of-flight mass spectrometry(GC–TOFMS)-based untargeted metabolomics was performed for an analysis of serum and liver tissues,and liquid chromatography–tandem mass spectrom-etry(LC–MS/MS)-based targeted metabolomics was performed.The potential functions of the metabo-lites were tested with in vitro and in vivo models of metabolic disorders.Our results first confirmed the metabolic benefits of APS in obese mice.Then,metabolomics analysis revealed that APS supplemen-tation reversed the HFD-induced metabolic changes,and identified 2-hydroxybutyric acid(2-HB)as a potential functional metabolite for APS activity that was significantly decreased by a HFD and reversed by APS.Further study indicated that 2-HB inhibited oleic acid(OA)-induced triglyceride(TG)accumula-tion.It was also found to stimulate the expression of proteins in lipid degradation in hepatocytes and TG lipolysis in 3T3-L1 cells.Moreover,it was found to reduce serum TG and regulate the proteins involved in lipid degradation in high-fat and high-sucrose(HFHS)-fed mice.In conclusion,our study demonstrates that the metabolic benefits of APS are at least partially due to 2-HB generation,which modulated lipid metabolism both in vitro and in vivo.Our results also highlight that functional metabolomics is practical for investigating the mechanism underlying the systemic benefits of plant polysaccharides. 展开更多
关键词 Astragalus polysaccharides(APS) Functional metabolomics 2-Hydroxybutyric acid Obesity
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Cross-Layer Framework for Capacity Analysis in Multiuser Ultra-Dense Networks with Cell DTx 被引量:4
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作者 Qing Li yu Chen +2 位作者 Qimei Cui yu gu guoqiang Mao 《China Communications》 SCIE CSCD 2019年第9期106-121,共16页
Cell discontinuous transmission(Cell DTx)is a key technology to mitigate inter-cell interference(ICI)in ultra-dense networks(UDNs).The aim of this work is to understand the impact of Cell DTx on physical-layer sum rat... Cell discontinuous transmission(Cell DTx)is a key technology to mitigate inter-cell interference(ICI)in ultra-dense networks(UDNs).The aim of this work is to understand the impact of Cell DTx on physical-layer sum rates of SBSs and link-layer quality-of-service(QoS)performance in multiuser UDNs.In this work,we develop a cross-layer framework for capacity analysis in multiuser UDNs with Cell DTx.In particular,we first extend the traditional one-dimensional effective capacity model to a new multidimensional effective capacity model to derive the sum rate and the effective capacity.Moreover,we propose a new iterative bisection search algorithm that is capable of approximating QoS performance.The convergence of this new algorithm to a unique QoS exponent vector is later proved.Finally,we apply this framework to the round-robin and the max-C/I scheduling policies.Simulation results show that our framework is accurate in approximating 1)queue length distribution,2)delay distribution and 3)sum rates under the above two scheduling policies,and further show that with the Cell DTx,systems have approximately 30% higher sum rate and 35% smaller average delay than those in full-buffer scenarios. 展开更多
关键词 effective capacity QoS performance SUM rates MULTIUSER scheduling ultra-dense network (UDN)
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Radiation-induced cross-linking:a novel avenue to permanent 3D modification of polymeric membranes 被引量:5
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作者 yu gu Bo-Wu Zhang +4 位作者 Zhen guo Ji-Hao Li Ming yu Lin-Fan Li Jing-Ye Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第7期31-45,共15页
Membrane fouling is always the biggest problem in the practice of membrane separation technologies,which strongly impacts their applicability,separation efficiency,cost effectiveness,and service lifespan.Herein,a simp... Membrane fouling is always the biggest problem in the practice of membrane separation technologies,which strongly impacts their applicability,separation efficiency,cost effectiveness,and service lifespan.Herein,a simple but effective 3D modification approach was designed for permanently functionalizing polymeric membranes by directly cross-linking polyvinyl alcohol(PVA)under gamma-ray irradiation at room temperature without any additives.After the modification,a PVA layer was constructed on the membrane surface and the pore inner surface of polyvinylidene fluoride(PVDF)membranes.This endowed them with good hydrophilicity,low adsorption of protein model foulants,and easy recoverability properties.In addition,the pore size and distribution were customized by controlling the PVA concentration,which enhanced the rejection ability of the resultant membranes and converted them from microfiltration to ultrafiltration.The crosslinked PVA layer was equipped with the resultant membranes with good resistance to chemical cleaning by acidic,alkaline,and oxidative reagents,which could greatly prolong the membrane service lifetime.Furthermore,this approach was demonstrated as a universal method to modify PVDF membranes with other hydrophilic macromolecular modifiers,including polyethylene glycol,sodium alginate,and polyvinyl pyrrolidone.This modification of the membranes effectively endowed them with good hydrophilicity and antifouling properties,as expected. 展开更多
关键词 Ultrafiltration membrane ANTIFOULING 3D modification GAMMA-RAY Cross-linking
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