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Unsaturated bi-heterometal clusters in metal-vacancy sites of 2D MoS2 for efficient hydrogen evolution 被引量:1
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作者 Gonglei Shao Jie Xu +4 位作者 Shasha Gao Zhang Zhang Song Liu Xu Zhang zhen zhou 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期264-275,共12页
The valence states and coordination structures of doped heterometal atoms in two-dimensional(2D)nanomaterials lack predictable regulation strategies.Hence,a robust method is proposed to form unsaturated heteroatom clu... The valence states and coordination structures of doped heterometal atoms in two-dimensional(2D)nanomaterials lack predictable regulation strategies.Hence,a robust method is proposed to form unsaturated heteroatom clusters via the metal-vacancy restraint mechanism,which can precisely regulate the bonding and valence state of heterometal atoms doped in 2D molybdenum disulfide.The unsaturated valence state of heterometal Pt and Ru cluster atoms form a spatial coordination structure with Pt–S and Ru–O–S as catalytically active sites.Among them,the strong binding energy of negatively charged suspended S and O sites for H+,as well as the weak adsorption of positively charged unsaturated heterometal atoms for H*,reduces the energy barrier of the hydrogen evolution reaction proved by theoretical calculation.Whereupon,the electrocatalytic hydrogen evolution performance is markedly improved by the ensemble effect of unsaturated heterometal atoms and highlighted with an overpotential of 84 mV and Tafel slope of 68.5 mV dec^(−1).In brief,this metal vacancy-induced valence state regulation of heterometal can manipulate the coordination structure and catalytic activity of heterometal atoms doped in the 2D atomic lattice but not limited to 2D nanomaterials. 展开更多
关键词 CLUSTERS hydrogen evolution reaction metal vacancy MOS2 unsaturated heterometal
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Engineering electrolyte additives for stable zinc-based aqueous batteries:Insights and prospects
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作者 Tao Liu Xusheng Dong +7 位作者 Bin Tang Ruizheng Zhao Jie Xu Hongpeng Li Shasha Gao Yongzheng Fang Dongliang Chao zhen zhou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期311-326,共16页
Zn-based aqueous batteries(ZABs) are gaining widespread popularity due to their low cost and high safety profile. However, the application of ZABs faces significant challenges, such as dendrite growth and parasitic re... Zn-based aqueous batteries(ZABs) are gaining widespread popularity due to their low cost and high safety profile. However, the application of ZABs faces significant challenges, such as dendrite growth and parasitic reactions of metallic Zn anodes. Therefore, achieving high-energy–density ZABs necessitates addressing the fundamental thermodynamics and kinetics of Zn anodes. Various strategies are available to mitigate these challenges, with electrolyte additive engineering emerging as one of the most efficient and promising approaches. Despite considerable research in this field, a comprehensive understanding of the intrinsic mechanisms behind the high performance of electrolyte additives remains limited. This review aims to provide a detailed introduction to functional electrolyte additives and thoroughly explore their underlying mechanisms. Additionally, it discusses potential directions and perspectives in additive engineering for ZABs, offering insights into future development and guidelines for achieving high-performance ZABs. 展开更多
关键词 Aqueous batteries Zn anodes Electrolyte additive engineering Interfacial chemistry Electrochemical mechanisms
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Experimental study of core MHD behavior and a novel algorithm for rational surface detection based on profile reflectometry in EAST
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作者 叶凯萱 周振 +20 位作者 张涛 马九阳 王嵎民 李恭顺 耿康宁 吴茗甫 文斐 黄佳 张洋 邵林明 杨书琪 钟富彬 高善露 喻琳 周子强 向皓明 韩翔 张寿彪 李国强 高翔 the EAST Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期66-75,共10页
Microwave reflectometry is a powerful diagnostic that can measure the density profile and localized turbulence with high spatial and temporal resolution and will be used in ITER,so understanding the influence of plasm... Microwave reflectometry is a powerful diagnostic that can measure the density profile and localized turbulence with high spatial and temporal resolution and will be used in ITER,so understanding the influence of plasma perturbations on the reflect signal is important.The characteristics of the reflect signal from profile reflectometry,the time-of-flight(TOF)signal associated with the MHD instabilities,are investigated in EAST.Using a 1D full-wave simulation code by the Finite-DifferenceTime-Domain(FDTD)method,it is well validated that the local density flattening could induce the discontinuity of the simulated TOF signal and an obvious change of reflect amplitude.Experimental TOF signals under different types of MHD instabilities(sawtooth,sawtooth precursors and tearing mode)are studied in detail and show agreement with the simulation.Two new improved algorithms for detecting and localizing the radial positions of the low-order rational surface,the cross-correlation and gradient threshold(CGT)method and the 2D convolutional neural network approach(CNN)are presented for the first time.It is concluded that TOF signal analysis from profile reflectometry can provide a straightforward and localized measurement of the plasma perturbation from the edge to the core simultaneously and may be a complement or correction to the q-profile control,which will be beneficial for the advanced tokamak operation. 展开更多
关键词 MHD instabilities profile reflectometry rational surface detection convolutional neural network(CNN) EAST tokamak
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Observation of Doppler shift f_(D) modulated by the internal kink mode using conventional reflectometry in the EAST tokamak
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作者 李恭顺 张涛 +18 位作者 耿康宁 文斐 叶凯萱 徐立清 朱翔 张学习 钟富彬 周振 杨书琪 周子强 喻琳 兰婷 王守信 提昂 张寿彪 刘海庆 李国强 高翔 the EAST Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期1-9,共9页
In this paper we present a new experimental observation using a conventional reflectometry technique,poloidal correlation reflectometry(PCR),in the Experimental Advanced Superconducting Tokamak(EAST).The turbulence sp... In this paper we present a new experimental observation using a conventional reflectometry technique,poloidal correlation reflectometry(PCR),in the Experimental Advanced Superconducting Tokamak(EAST).The turbulence spectrum detected by the PCR system exhibits an asymmetry and induced Doppler shift f_(D)during the internal kink mode(IKM)rotation phase.This Doppler shift f_(D)is the target measurement of Doppler reflectometry,but captured by conventional reflectometry.Results show that the Doppler shift f_(D)is modulated by the periodic changes in the effective angle between the probing wave and cutoff layer normal,but not by plasma turbulence.The fishbone mode and saturated long-lived mode are typical IKMs,and this modulation phenomenon is observed in both cases.Moreover,the value of the Doppler shift f_(D)is positively correlated with the amplitude of the IKM,even when the latter is small.However,the positive and negative frequency components of the Doppler shift f_(D)can be asymmetric,which is related to the plasma configuration.A simulated analysis is performed by ray tracing to verify these observations.These results establish a clear link between f_(D)and IKM rotation,and are helpful for studying the characteristics of IKM and related physical phenomena. 展开更多
关键词 microwave reflectometry Doppler shift internal kink mode
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低能电子轰击引起氧化铝钝化膜BCMOS传感器暗电流变化研究
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作者 闫磊 石峰 +7 位作者 程宏昌 焦岗成 杨晔 肖超 樊海波 郑舟 董海晨 何惠洋 《红外技术》 CSCD 北大核心 2024年第3期342-346,共5页
针对低能电子(电子能量为300~1500 eV)轰击引起氧化铝钝化层BCMOS(Back-thinned Complementary Metal-Oxide-Semiconductor,BCMOS)图像传感器暗电流增加问题,设计了电子轰击BCMOS图像传感器实验,经统计发现,对于厚度为10 nm的氧化铝钝化... 针对低能电子(电子能量为300~1500 eV)轰击引起氧化铝钝化层BCMOS(Back-thinned Complementary Metal-Oxide-Semiconductor,BCMOS)图像传感器暗电流增加问题,设计了电子轰击BCMOS图像传感器实验,经统计发现,对于厚度为10 nm的氧化铝钝化层BCMOS图像传感器,轰击能量大于600 eV时暗电流增加速率明显;轰击电子能量不超过1.5 keV时,暗电流存在最大值,约为12000 e-/pixel/s;电子轰击后的BCMOS图像传感器在电子干燥柜中静置时,其暗电流呈指数趋势下降。通过分析指出入射电子引起氧化铝钝化层与硅界面处缺陷态增加,是引起上述现象的主要原因。 展开更多
关键词 暗电流 电子轰击 背减薄CMOS 氧化铝钝化层
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A leap by the rise of solid-state electrolytes for Li-air batteries 被引量:1
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作者 Kecheng Pan Minghui Li +5 位作者 Weicheng Wang Shuochao Xing Yaying Dou Shasha Gao Zhang Zhang zhen zhou 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第4期939-944,共6页
Li-air batteries have attracted extensive attention because of their ultrahigh theoretical energy density. However, the potential safety hazard of flammable organic liquid electrolytes hinders their practical applicat... Li-air batteries have attracted extensive attention because of their ultrahigh theoretical energy density. However, the potential safety hazard of flammable organic liquid electrolytes hinders their practical applications. Replacing liquid electrolytes with solidstate electrolytes(SSEs) is expected to fundamentally overcome the safety issues. In this work, we focus on the development and challenge of solid-state Li-air batteries(SSLABs). The rise of different types of SSEs, interfacial compatibility and verifiability in SSLABs are presented. The corresponding strategies and prospects of SSLABs are also proposed. In particular, combining machine learning method with experiment and in situ(or operando)techniques is imperative to accelerate the development of SSLABs. 展开更多
关键词 Solid-state Li-air batteries Solid-state electrolytes Interfacial compatibility and verifiability
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One-year observation of the mixing states of oxygenated organics-containing single particles in Guangzhou,China 被引量:1
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作者 Liyuan Mao Suxia Yang +6 位作者 Xiaoya Cheng Sulin Liu Duanying Chen zhen zhou Mei Li Chenglei Pei Chunlei Cheng 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2024年第5期155-169,共15页
Oxygenated organic molecules(OOMs)play an important role in the formation of secondary organic aerosols(SOAs),but the mixing states of OOMs are still unclear.This study investigates the mixing states of OOM-containing... Oxygenated organic molecules(OOMs)play an important role in the formation of secondary organic aerosols(SOAs),but the mixing states of OOMs are still unclear.This study investigates the mixing states of OOM-containing single particles from the measurements taken using a single particle aerosol mass spectrometer in Guangzhou,China in 2022.Generally,the particle counts of OOM particles and the mass concentration of secondary organic carbon(SOC)exhibited similar temporal trends throughout the entire year.The OOM particles were consistently enriched in secondary ions,including ^(16)O^(−),^(26)CN^(−),^(46)NO_(2)^(−),^(62)NO_(3)^(−),and ^(97)HSO_(4)^(−).In contrast,the number fractions and diurnal patterns of OOM particles among the total detected particles showed similar distributions in August and October;however,the SOC ratios in fine particulate matter were quite different,suggesting that there were different mixing states of single-particle oxygenated organics.In addition,further classification results indicated that the OOM particles were more aged in October than August,even though the SOC ratios were higher in August.Furthermore,the distribution of hydrocarbon fragments exhibited a notable decrease from January to October,emphasizing the more aged state of the organics in October.In addition,the sharp increase in elemental carbon(EC)-OOM particles in the afternoon in October suggests the potential role of EC in the aging process of organics.Overall,in contrast to the bulk analysis of SOC mass concentration,the mixing states of the OOM particles provide insights into the formation process of SOAs in field studies. 展开更多
关键词 Oxygenated organics Single particles Mixing state Secondary formation PHOTOCHEMISTRY
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Mixing states and secondary formation processes of organic nitrogen-containing single particles in Guangzhou,China
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作者 Lijun Yun Chunlei Cheng +9 位作者 Suxia Yang Zaihua Wang Mei Li Qi En Zhong LiyuanMao Sulin Liu Xiaoya Cheng Duanying Chen Fan Yang zhen zhou 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第4期62-73,共12页
Organic nitrogen(ON)compounds play a significant role in the light absorption of brown carbon and the formation of organic aerosols,however,the mixing state,secondary formation processes,and influencing factors of ON ... Organic nitrogen(ON)compounds play a significant role in the light absorption of brown carbon and the formation of organic aerosols,however,the mixing state,secondary formation processes,and influencing factors of ON compounds are still unclear.This paper reports on the mixing state of ON-containing particles based on measurements obtained using a highperformance single particle aerosol mass spectrometer in January 2020 in Guangzhou.The ON-containing particles accounted for 21% of the total detected single particles,and the particle count and number fraction of the ON-containing particles were two times higher at night than during the day.The prominent increase in the content of ON-containing particles with the enhancement of NO_xmainly occurred at night,and accompanied by high relative humidity and nitrate,which were associated with heterogeneous reactions between organics and gaseous NO_(x)and/or NO_(3)radical.The synchronous decreases in ON-containing particles and the mass absorption coefficient of water-soluble extracts at 365 nm in the afternoon may be associated with photo-bleaching of the ON species in the particles.In addition,the positive matrix factorization analysis found five factors dominated the formation processes of ON particles,and the nitrate factor(33%)mainly contributed to the production of ON particles at night.The results of this study provide unique insights into the mixing states and secondary formation processes of the ON-containing particles. 展开更多
关键词 Organic nitrogen compounds Single particles Mixing state Secondary formation Nighttime chemistry
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非结核分枝杆菌肺病的CT分型及其临床特征分析(附132例报告) 被引量:6
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作者 李多 房坤 +2 位作者 王珏 周震 吕平欣 《中国防痨杂志》 CAS CSCD 2019年第2期202-209,共8页
目的分析非结核分枝杆菌肺病的CT分型,以及不同型别患者的临床及CT表现特点。方法回顾性分析2011年11月至2018年1月首都医科大学附属北京胸科医院确诊的132例非结核分枝杆菌肺病患者的临床及CT资料,根据CT表现分为上叶空洞型、结节支气... 目的分析非结核分枝杆菌肺病的CT分型,以及不同型别患者的临床及CT表现特点。方法回顾性分析2011年11月至2018年1月首都医科大学附属北京胸科医院确诊的132例非结核分枝杆菌肺病患者的临床及CT资料,根据CT表现分为上叶空洞型、结节支气管扩张型、混合型和不易分类型4种类型,统计分析不同CT分型患者的临床及CT特征。采用SPSS17.0软件进行统计学分析,计数资料采用χ^2检验或连续校正χ^2检验,计量资料采用t检验或方差分析,均以P<0.05为差异有统计学意义;4组不同CT型别患者的临床统计数据进行两两比较时,以P<0.008为差异有统计学意义。结果132例非结核分枝杆菌肺病CT分型结果为:上叶空洞型36例(27.3%),结节支气管扩张型61例(46.2%),混合型15例(11.4%),不易分类型20例(15.2%)。非结核分枝杆菌肺病不同CT分型组中,男性构成比由高到低分别为上叶空洞型(86.1%,31/36)、不易分类型(70.0%,14/20),混合型(53.3%,8/15)和结节支气管扩张型(24.6%,15/61),差异有统计学意义(χ^2=37.712,P<0.001)。上叶空洞型、结节支气管扩张型、混合型和不易分类型患者平均年龄分别为(58.5±13.8)岁、(58.1±13.3)岁、(61.3±10.4)岁和(51.0±17.0)岁,差异无统计学意义(F=1.875,P=0.140)。上叶空洞型患者中吸烟者占64.7%(22/34),明显高于结节支气管扩张型患者(13.0%,7/54)(χ^2=25.258,P<0.001)。上叶空洞型患者发生肺气肿者占66.7%(24/36),发生间质纤维化改变者占33.3%(12/36),明显高于结节支气管扩张型[分别为13.1%(8/61)和0.0%(0/61)](χ^2=29.369、23.204,P值均<0.001)。上叶空洞型并发胸膜增厚者占61.1%(22/36),明显高于结节支气管扩张型(23.0%,14/61)(χ^2=14.125,P<0.001);混合型患者并发胸膜增厚者占66.7%(10/15),同样高于结节支气管扩张型(χ^2=10.649,P=0.001)。结论非结核分枝杆菌肺病中,结节支气管扩张型最常见;上叶空洞型好发于男性有肺气肿和(或)间质纤维化改变的患者,结节支气管扩张型好发于女性无肺部基础疾病(未并发肺部其他种类疾病,包括肺气肿、间质纤维化等)的患者。 展开更多
关键词 分枝杆菌感染 非典型性 肺疾病 体层摄影术 X线计算机 诊断显像
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A study on the mechanism of acupuncture treatment of acne based on immune inflammation
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作者 Chu-Yi Zhang Rui Jin +1 位作者 Yi-Jun Feng zhen zhou 《TMR Non-Drug Therapy》 2023年第1期8-13,共6页
Acne is a chronic inflammatory skin disease involving hair follicle sebaceous glands,which is characterized by acne,papules,pustules,nodules,cysts and so on.The disorder of immune inflammation is the key link.A variet... Acne is a chronic inflammatory skin disease involving hair follicle sebaceous glands,which is characterized by acne,papules,pustules,nodules,cysts and so on.The disorder of immune inflammation is the key link.A variety of factors participate in the immune inflammatory response of acne and interact with each other,leading to the occurrence and development of acne inflammation.Acupuncture can regulate the immune and inflammatory response through many links and improve the skin lesions.This study explains potential mechanisms of acupuncture in the treatment of acne by regulating the body's immune inflammatory response,in order to provide new ideas. 展开更多
关键词 ACUPUNCTURE ACNE IMMUNITY inflammatory reaction MECHANISM
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基于深度学习的人工智能胸部CT肺结节检测效能评估 被引量:93
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作者 李欣菱 郭芳芳 +6 位作者 周振 张番栋 王卿 彭志君 苏大同 范亚光 王颖 《中国肺癌杂志》 CAS CSCD 北大核心 2019年第6期336-340,共5页
背景与目的肺结节精确检测是实现肺癌早诊的基础。基于深度学习的人工智能在肺内结节检测领域发展迅速,对其效能进行验证是促进其应用于临床的前提。本研究旨在评估基于深度学习技术的人工智能软件在胸部计算机断层扫描(computed tomogr... 背景与目的肺结节精确检测是实现肺癌早诊的基础。基于深度学习的人工智能在肺内结节检测领域发展迅速,对其效能进行验证是促进其应用于临床的前提。本研究旨在评估基于深度学习技术的人工智能软件在胸部计算机断层扫描(computed tomography, CT)恶性及非钙化结节检出中的价值。方法由天津医科大学总医院自建胸部CT肺结节数据库中随机抽取200例胸部CT数据,包含病理证实的肺癌及随访结节病例,导入肺结节人工智能识别系统,记录软件自动识别结节,并与原始影像报告结果进行对比。人工智能软件及阅片者检测到的结节由2名胸部专家进行评估并记录其大小及特征。计算灵敏度、假阳性率评估人工智能软件及医师的结节检测效能,应用McNemar检验确定二者之间是否存在显著性差异。结果 200例胸部多层螺旋CT共包含非钙化结节889枚,其中肺癌结节133枚,小于5 mm结节442枚。人工智能及放射科医师肺癌检出率皆为100%。人工智能软件结节检测灵敏度明显高于放射科医师(99.1%vs 43%, P<0.001)。人工智能总体假阳性率为每例CT 4.9个,排除5 mm以下结节后降为1.5个。结论基于深度学习的人工智能软件能实现恶性肺结节的无漏诊检出,具有较医师更高的结节检出灵敏度,在排除微小结节后可降低假阳性率。 展开更多
关键词 计算机体层成像 肺结节 深度学习 人工智能 检出
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《下一代二次电池》专辑序言 被引量:1
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作者 周震 董全峰 《电化学》 CAS CSCD 北大核心 2019年第1期1-2,共2页
随着人类社会的迅速发展,能源和环境问题逐渐成为人们关注的焦点.化石燃料的过度依赖和使用所导致的全球变暖和环境污染日趋严重,国内大范围高频率的雾霾天气引起了民众的广泛担心,迫切要求加快能源技术创新,建设清洁低碳、安全高效的... 随着人类社会的迅速发展,能源和环境问题逐渐成为人们关注的焦点.化石燃料的过度依赖和使用所导致的全球变暖和环境污染日趋严重,国内大范围高频率的雾霾天气引起了民众的广泛担心,迫切要求加快能源技术创新,建设清洁低碳、安全高效的新能源体系.风能、太阳能和潮汐能等清洁可再生能源在空间和时间上分布不均,电化学储能是实现其广泛应用的关键环节.以锂离子电池为代表的二次电池技术一经出现就在数码产品等移动电源市场占据了主导地位,然而长距离续航里程的电动汽车和发展新能源需要的智能电网等对储能技术提出了更高的要求.因此,下一代二次电池储能体系的研究发展至关重要,对我国能源、交通、信息和国防等领域的高速发展和相关战略新兴产业的形成和壮大具有重要意义. 展开更多
关键词 二次电池 能源体系 序言 专辑 可再生能源 锂离子电池 人类社会 环境污染
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Picroside Ⅱ down-regulates matrix metalloproteinase-9 expression following cerebral ischemia/reperfusion injury in rats 被引量:13
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作者 Xiang Li Xinying Xu +4 位作者 zhen Li Yunliang Guo Qin Li Xiaodan Li zhen zhou 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第18期1403-1407,共5页
Studies have shown that Picroside Ⅱ attenuates inflammatory reactions following brain ischemia through the inhibition of the TLR-4-NF-KB signal transduction pathway, and ameliorates cerebral edema through the reducti... Studies have shown that Picroside Ⅱ attenuates inflammatory reactions following brain ischemia through the inhibition of the TLR-4-NF-KB signal transduction pathway, and ameliorates cerebral edema through the reduction of aquaporin-4 expression. Matrix metalloproteinase-9 (MMP-9), located downstream of the TLR-4-NF-KB signal transduction pathway, can degrade the neurovascular matrix, damage the blood-brain barrier to induce cerebral edema, and directly result in neuronal apoptosis and brain injury, Therefore, the present study further observed MMP-9 expression in the brain tissues of rats with cerebral ischemia/reperfusion injury following Picroside Ⅱ treatment. Results demonstrated that Picroside Ⅱ significantly reduced MMP-9 expression in ischemic brain tissues, as well as neuronal apoptosis and brain infarct volume, suggesting Picroside Ⅱ exhibits neuroprotection by down-regulating MMP-9 expression and inhibiting cell apoptosis. 展开更多
关键词 Picroside cerebral ischemia/reperfusion injury APOPTOSIS matrix metalloproteinase-9 RATS neural regeneration
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Anti-oxidant effect of picroside II in a rat model of cerebral ischemia/reperfusion injury 被引量:9
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作者 Li Sun Xiaodan Li +3 位作者 Ling Wang Lihua Qin Yunliang Guo zhen zhou 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第15期1141-1146,共6页
Picroside II,the major active component of picroside,has been shown to induce PC12 cell axonal growth and relieve free radical damage.In vivo experiments have demonstrated that picroside II can improve neurological fu... Picroside II,the major active component of picroside,has been shown to induce PC12 cell axonal growth and relieve free radical damage.In vivo experiments have demonstrated that picroside II can improve neurological function in rats with cerebral ischemia/reperfusion injuries.In the present in vivo study,enzyme-linked immunosorbent assay and immunohistochemistry revealed that picroside II increased superoxide dismutase content and reduced inducible nitric oxide synthase content in the ischemic hemisphere.The effects of picroside II were similar to those of salvianic acid A sodium,an active control drug.These results indicate that picroside II exerts a neuroprotective effect,possibly by downregulating inducible nitric oxide synthase expression,increasing superoxide dismutase activity,and inhibiting neuronal apoptosis. 展开更多
关键词 picroside II salvianic acid A sodium brain ischemia reperfusion injury apoptosis inducible nitric oxide synthase superoxide dismutase neural regeneration
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Ethylene Emission as a Potential Indicator of Fuji Apple Flavor Quality Evaluation Under Low Temperature 被引量:22
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作者 Weiyan Qi Haijing Wang +4 位作者 zhen zhou Peng Yang Wenbin Wu Zhemin Li Xian Li 《Horticultural Plant Journal》 SCIE 2020年第4期231-239,共9页
Fuji apple(Malus×domestica Borkh.)is a popular fruit cultivar and occupies an important position in the fruit market due to its excellent flavor and storage quality.Ethylene emission can induce respiration,which ... Fuji apple(Malus×domestica Borkh.)is a popular fruit cultivar and occupies an important position in the fruit market due to its excellent flavor and storage quality.Ethylene emission can induce respiration,which would reduce postharvest quality and increase storage losses.In order to maintain fruit quality and extend shelf life,apples are usually stored in a low-temperature environment after harvest to reduce the formation of ethylene.Volatile aroma components are regarded as one of the most important aspects of flavor quality and a key factor for apple quality grading and customer satisfaction.Ethylene emission and its relationship with volatile aromas during low temperature,however,have not been determined.In this study,the dynamic changes of volatile aroma compounds of Fuji apples stored at 4°C were detected and analyzed for 42 days.The variation of ethylene released from Fuji apple was studied correspondingly.The results showed that ethyl butyrate,ethyl caproate,ethyl 2-methylbutyrate and 2-methylbutyl acetate were the main aroma components of Fuji apple.The change in ethylene emission and the normalized peak area of volatile aroma compounds exhibited a similar tendency that increased significantly from the 3rd day to the peak on the 14th day and then decreased;there was a positive linear correlation between them with a correlation coefficient of 0.79(P<0.05).Therefore,ethylene release can be used as a potential indicator for evaluation of volatile aroma compounds in apples.Using ethylene emission as an indicator could reduce the difficulty and complexity of volatile aroma evaluation,which could be a new non-destructive inspection choice for apple flavor quality assessment. 展开更多
关键词 APPLE AROMA flavor quality ETHYLENE correlation analysis
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Recent progress in rechargeable alkali metal-air batteries 被引量:13
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作者 Xin Zhang Xin-Gai Wang +1 位作者 Zhaojun Xie zhen zhou 《Green Energy & Environment》 SCIE 2016年第1期4-17,共14页
Rechargeable alkali metal-air batteries are considered as the most promising candidate for the power source of electric vehicles(EVs) due to their high energy density. However, the practical application of metal-air b... Rechargeable alkali metal-air batteries are considered as the most promising candidate for the power source of electric vehicles(EVs) due to their high energy density. However, the practical application of metal-air batteries is still challenging. In the past decade, many strategies have been purposed and explored, which promoted the development of metal-air batteries. The reaction mechanisms have been gradually clarified and catalysts have been rationally designed for air cathodes. In this review, we summarize the recent development of alkali metal-air batteries from four parts: metal anodes, electrolytes, air cathodes and reactant gases, wherein we highlight the important achievement in this filed. Finally problems and prospective are discussed towards the future development of alkali metal-air batteries. 展开更多
关键词 Metal-air batteries Alkali metal anodes Electrolytes Ionic liquids Air cathodes
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circPTPN4 regulates myogenesis via the miR-499-3p/NAMPT axis 被引量:6
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作者 Bolin Cai Manting Ma +4 位作者 zhen zhou Shaofen Kong Jing Zhang Xiquan Zhang Qinghua Nie 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2022年第3期682-696,共15页
Background:Circular RNAs(circ RNAs)are a novel class of endogenous nc RNA,which widely exist in the transcriptomes of different species and tissues.Recent studies indicate important roles for circ RNAs in the regulati... Background:Circular RNAs(circ RNAs)are a novel class of endogenous nc RNA,which widely exist in the transcriptomes of different species and tissues.Recent studies indicate important roles for circ RNAs in the regulation of gene expression by acting as competing endogenous RNAs(ce RNAs).However,the specific role of circ RNAs in myogenesis is still poorly understood.In this study,we attempted to systematically identify the circ RNAs involved in myogenesis and analyze the biological functions of circ RNAs in chicken skeletal muscle development.Results:In total,532 circ RNAs were identified as being differentially expressed between pectoralis major(PEM)and soleus(SOL)in 7-week-old Xinghua chicken.Among them,a novel circ RNA(novel_circ_002621),generated by PTPN4 gene,was named circ PTPN4 and identified.circ PTPN4 is highly expressed in skeletal muscle,and its expression level is upregulated during myoblast differentiation.circ PTPN4 facilitates the proliferation and differentiation of myoblast.Moreover,circ PTPN4 suppresses mitochondria biogenesis and activates fast-twitch muscle phenotype.Mechanistically,circ PTPN4 can function as a ce RNA to regulate NAMPT expression by sponging mi R-499-3p,thus participating in AMPK signaling.Conclusions:circ PTPN4 functions as a ce RNA to regulate NAMPT expression by sponging mi R-499-3p,thus promoting the proliferation and differentiation of myoblast,as well as activating fast-twitch muscle phenotype. 展开更多
关键词 CHICKEN Circ PTPN4 Circular RNA MiR-499-3p MYOGENESIS NAMPT The transformation of myofiber
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Targeted design of advanced electrocatalysts by machine learning 被引量:7
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作者 Letian Chen Xu Zhang +3 位作者 An Chen Sai Yao Xu Hu zhen zhou 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第1期11-32,共22页
Exploring the production and application of clean energy has always been the core of sustainable development.As a clean and sustainable technology,electrocatalysis has been receiving widespread attention.It is crucial... Exploring the production and application of clean energy has always been the core of sustainable development.As a clean and sustainable technology,electrocatalysis has been receiving widespread attention.It is crucial to achieve efficient,stable and cheap electrocatalysts.However,the traditional“trial and error”method is time-consuming,laborious and costly.In recent years,with the significant increase in computing power,computations have played an important role in electrocatalyst design.Nevertheless,it is still difficult to search for advanced electrocatalysts in the vast chemical space through traditional density functional theory(DFT)computations.Fortunately,the development of machine learning and interdisciplinary integration will inject new impetus into targeted design of electrocatalysts.Machine learning is able to predict electrochemical performances with an accuracy close to DFT.Here we provide an overview of the application of machine learning in electrocatalyst design,including the prediction of structure,thermodynamic properties and kinetic barriers.We also discuss the potential of explicit solvent model combined with machine learning molecular dynamics in this field.Finally,the favorable circumstances and challenges are outlined for the future development of machine learning in electrocatalysis.The studies on electrochemical processes by machine learning will further realize targeted design of high-efficiency electrocatalysts. 展开更多
关键词 ELECTROCATALYST Machine learning Targeted design Thermodynamics properties Kinetic barrier
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Bifunctional electrocatalysts for rechargeable Zn-air batteries 被引量:7
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作者 Yibo Guo Ya-Nan Chen +1 位作者 Huijuan Cui zhen zhou 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第9期1298-1310,共13页
Zn-air batteries have attracted extensive attention for their unique features including high energy density,safety,low cost and environmental friendliness.However,due to their poor chargeability and low efficiency,the... Zn-air batteries have attracted extensive attention for their unique features including high energy density,safety,low cost and environmental friendliness.However,due to their poor chargeability and low efficiency,the practical application remains a challenge.The main obstacles are the intrinsic slow reaction kinetics on air cathodes,including oxygen reduction reaction during the discharging process and oxygen evolution reaction during the recharging process.Searching for efficient bifunctional oxygen electrocatalysts is key to solve these problems.In this review,the configuration and fundamental oxygen electrochemical reactions on air cathodes are briefly introduced for Zn-air batteries first.Then,the latest bifunctional oxygen electrocatalysts are summarized in detail.Finally,the perspectives are provided for the future investigations on bifunctional oxygen electrocatalysts. 展开更多
关键词 Bifunctional electrocatalysts Oxygen-reduction reaction Oxygen-evolution reaction Zn-air batteries Hybrid materials
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The Research on 220GHz Multicarrier High-Speed Communication System 被引量:8
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作者 Zhongqian Niu Bo Zhang +9 位作者 Jiale Wang Ke Liu Zhi Chen Ke Yang zhen zhou Yong Fan Yaohui Zhang Dongfeng Ji Yinian Feng Yang Liu 《China Communications》 SCIE CSCD 2020年第3期131-139,共9页
This paper presents our investigation into a 220 GHz multicarrier highspeed communication system based on solid state transceivers.The proposed system has eased the demand of high sampling rate analog-to-digital conve... This paper presents our investigation into a 220 GHz multicarrier highspeed communication system based on solid state transceivers.The proposed system has eased the demand of high sampling rate analog-to-digital converter(ADC)by providing several signal carriers in microwave band and converting them to 220 GHz channel.The system consists of a set of 220 GHz solid-state transceiver with 2 signal carriers,two basebands for 4 GSPS ADCs.It has achieved 12.8 Gbps rate real-time signal transmission using 16QAM modulation over a distance of 20 m without any other auxiliary equipment or test instruments.The baseband algorithm overcomes the problem of frequency difference generates by non-coherent structure,which guarantees the feasibility of long-distance transmission application.Most importantly,the proposed system has already carried out multi-channel 8K video parallel transmission through switch equipment,which shows the multicarrier high-speed communication system in submillimeter wave has great application prospects.To the best of the authors’knowledge,this is the first all-solid-state electronics multicarrier communication system in submillimeter and terahertz band. 展开更多
关键词 CIRCUITS and SYSTEMS COMMUNICATION SYSTEMS SUBMILLIMETER wave COMMUNICATION solid state CIRCUITS
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