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Ecological Factors Drive the Accumulation of Active Components in Codonopsis pilosula
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作者 Menghan Li yuhui he +5 位作者 Changning Chen Li Liu Jia Xu Jiahao Cao Xiaotong Guo Linlin Dong 《Phyton-International Journal of Experimental Botany》 2025年第8期2575-2591,共17页
Codonopsis pilosula is a major Qi-tonifying medicinal herb,and its active composition is analyzed systematically.However,the relationship between its production origins and commodity specification grades with the acti... Codonopsis pilosula is a major Qi-tonifying medicinal herb,and its active composition is analyzed systematically.However,the relationship between its production origins and commodity specification grades with the active composition of C.pilosula lacks systematic research.This study integrates the HPLC and UV-Vis methodologies to evaluate the quality of C.pilosula from commodity specification grades and different origins,and it explores the correlation between ecological factors and production origins with active components.Here,network pharmacology is used to determine that lobetyolin,syringin,and tangshenoside I have potential efficacy in treating pulmonary fibrosis and oxidative stress.The HPLC and UV-Vis methods were employed to quantitatively analyse the levels of five active compounds from different origins and commodity specification grades.Ecological factors were collected from the different production origins with ArcGIS,and correlation analysis was conducted between these factors and the active components of C.pilosula to identify the key ecological influences that drive the accumulation of active compounds.Results showed that network pharmacology analyses indicated that the active components of C.pilosula,including lobetyolin,syringin,and tangshenoside I,bind to targets and exhibit antioxidant and antipulmonary fibrosis effects.Differences in the contents of active components across three commodity specification grades were not significant.The contents of active components in C.pilosula showed differences with varying origins,with the most variation observed in soluble sugar content,and notable variations are also observed in the levels of lobetyolin,syringin,and tangshenoside I,which could serve as potential biomarkers for different origins.Additionally,ecological factors influenced the accumulation of C.pilosula’s active components.The contents of soluble sugars and tangshenoside I were positively correlated with temperature and precipitation.Our study evaluated the active components of C.pilosula,and findings show that lobetyolin,syringin,and tangshenoside I have potential efficacy in treating pulmonary fibrosis and oxidative stress.The differences in the quality of C.pilosula across varying commodity specification grades are not significant.The different contents of C.pilosula across varying origins are significant,with soluble sugars and glycosides serving as potential markers for distinguishing C.pilosula from different origins.Moreover,ecological factors drove the accumulation of C.pilosula components.Soluble sugars and tangshenoside I content were particularly influenced by temperature and precipitation.Sand content and electrical conductivity significantly correlated with syringin,whereas organic carbon negatively influenced total flavonoids.This research provides a theoretical basis for the selection of the C.pilosula growing area and lays a foundation for the study of the C.pilosula quality standard. 展开更多
关键词 Codonopsis pilosula commodity specification grades producing origins LOBETYOLIN SYRINGIN tangshenoside I soluble sugar total flavonoids
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科尔沁沙质草地关键植物种群动态对降水变化的响应
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作者 刘新平 胡鸿姣 +3 位作者 何玉惠 徐远志 景家琪 张尧 《中国沙漠》 北大核心 2025年第4期43-56,共14页
干旱半干旱区陆地生态系统中,关键植物种群的动态变化是植被结构调整的核心驱动力,也是植被响应降水变化的生态基础。本研究以中国北方半干旱区科尔沁沙质草地植被为对象,通过降水变化控制实验,解析关键种群对降水变化的响应路径及其生... 干旱半干旱区陆地生态系统中,关键植物种群的动态变化是植被结构调整的核心驱动力,也是植被响应降水变化的生态基础。本研究以中国北方半干旱区科尔沁沙质草地植被为对象,通过降水变化控制实验,解析关键种群对降水变化的响应路径及其生态功能分异特征,进而识别植被结构的种群水平配置规律。结果表明:降水减少驱动多年生优势植物种被一年生植物替代,如糙隐子草(Cleistogenes squarrosa)的重要值和生态位宽度可由0.21和5.06降低至0,而降水增加仅微调各优势种的优势度。降水变化下,植被指示种功能分异明显:降水增加以多年生植物为主,如糙隐子草指示值可达0.25;降水减少以半灌木为主,如兴安胡枝子(Lespedeza bicolor)指示值可达0.23;阶段性干旱则为猪毛菜(Salsola collina)等一年生植物,指示值为0.39。植被泛化种对阶段性干旱较为敏感,植被特化种对极端降水变化较为敏感,二者生态位收缩均触发中性类群物种数占比增加以填补空缺。具有高重要值、高指示性、广生态位或特殊生态位的关键种均可对降水处理组间差异具有重要贡献。这些关键种群结构特征对降水的极端变化、减少及春季变化会更敏感。本研究强调结合降水格局与对应关键缓冲植物种来优化植被空间配置的可行性,可为半干旱沙质草地植被响应气候变化的适应性管理提供理论支撑。 展开更多
关键词 降水格局 植物种群 优势种 指示种 生态位
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降水量对半干旱沙质草地土壤胞外酶活性的影响
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作者 景家琪 刘新平 +4 位作者 何玉惠 丰洁 胡鸿姣 徐远志 张尧 《中国沙漠》 北大核心 2025年第4期368-377,共10页
土壤酶深度参与土壤系统的养分循环进程,是维系植物与土壤养分关联的核心纽带。土壤胞外酶活性对降水格局的变动极为敏感,在缺水且养分匮乏的沙质草地生态系统中尤为突出。本研究以半干旱沙质草地为研究对象,开展不同降水条件下土壤胞... 土壤酶深度参与土壤系统的养分循环进程,是维系植物与土壤养分关联的核心纽带。土壤胞外酶活性对降水格局的变动极为敏感,在缺水且养分匮乏的沙质草地生态系统中尤为突出。本研究以半干旱沙质草地为研究对象,开展不同降水条件下土壤胞外酶活性变化研究,确定沙质草地生态系统土壤胞外酶活性动态变化规律,揭示沙质草地土壤碳、氮、磷含量以及酶活性对短期降水变化的响应机制。结果显示:(1)减少30%降水条件下的植物地上生物量比自然条件显著降低(P<0.05),而土壤容重和电导率比自然条件下显著增加(P<0.05);(2)相较于对照组,增加60%降水处理使微生物碳限制程度以及微生物氮限制程度显著提高(P<0.05);(3)土壤胞外酶活性对水分波动响应较强,增加60%降水条件下纤维二糖水解酶活性提高到对照组的2.47倍,对应碳相关酶活性增加19.7%;而氮相关酶活性在对照组表现最大。 展开更多
关键词 降水变化 土壤酶活性 沙质草地 植物生物量 土壤理化性质
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半干旱沙质草地植物群落构建对降水的响应
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作者 景家琪 刘新平 +3 位作者 何玉惠 丰洁 胡鸿姣 徐远志 《中国沙漠》 北大核心 2025年第4期314-323,共10页
降水是影响半干旱沙质草地植被生长发育和系统稳定维持的关键因子。为探明降水变化如何影响固沙植物群落构建及其生产力,本文整合分析了2014—2023年的降水和半干旱沙质草地植被长期定位监测数据,研究了降水变化对植物群落结构组成、物... 降水是影响半干旱沙质草地植被生长发育和系统稳定维持的关键因子。为探明降水变化如何影响固沙植物群落构建及其生产力,本文整合分析了2014—2023年的降水和半干旱沙质草地植被长期定位监测数据,研究了降水变化对植物群落结构组成、物种多样性和生产力的影响。结果表明:(1)在40%的年降水变异内,多年生草本植物糙隐子草(Cleistogenes squarrosa)和二裂委陵菜(Potentilla bifurca)、一年生草本植物狗尾草(Setaria viridis)和尖头叶藜(Chenopodium acuminatum)及半灌木兴安胡枝子(Lespedeza bicolor)在10年间均为建群种,不受降水变化的影响,而在50%的年降水变异内,草本植物白草(Pennisetum centrasiaticum)和猪毛蒿(Artemisia scoparia)连续5年成为群落优势种,其余物种则随着降水变化呈现年际波动;(2)沙质草地植物群落多样性指数随降水增加而降低,群落丰富度、优势度和均匀度相对稳定,而功能群均匀度离散程度较高且总体上升;(3)沙质草地一年生草本植物和多年生草本植物的生物量与当年7月及生长季降水显著正相关,且二者地上生物量呈现增减互补的变化趋势,这一特征是维持系统生产力稳定的权衡对策,尤其在2018年和2022年表现尤为明显。降水直接决定半干旱沙质草地植物群落构建及其功能群多样性,可为预测半干旱沙质草地未来降水变化情景下的固沙植被群落演替,以及沙地生态系统植被稳定性维持和植被资源化利用提供理论支持。 展开更多
关键词 降水变化 群落构建 生物多样性 地上生物量
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Modification strategies for non-aqueous, highly proton-conductive benzimidazole-based high-temperature proton exchange membranes
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作者 Yunfa Dong Shijie Zhong +9 位作者 yuhui he Zhezhi Liu Shengyu Zhou Qun Li Yashuai Pang Haodong Xie Yuanpeng Ji Yuanpeng Liu Jiecai Han Weidong he 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第4期43-51,共9页
High-temperature proton exchange membranes(HT-PEMs) possess excellent thermal and outstanding electrochemical stability, providing an avenue to realize high-temperature proton exchange membranes fuel cells(HT-PEMFCs) ... High-temperature proton exchange membranes(HT-PEMs) possess excellent thermal and outstanding electrochemical stability, providing an avenue to realize high-temperature proton exchange membranes fuel cells(HT-PEMFCs) with both superior power density and long-term durability. Unfortunately, polybenzimidazole(PBI), a typical material for conventional HT-PEMs, fails to compromise the high nonaqueous proton conductivity and high mechanical properties, thus hindering their practical applications.Achieving efficient nonaqueous proton conduction is crucial for HT-PEMFC, and many insightful research works have been done in this area. However, there still lacks a report that integrates the host-vip interactions of phosphoric acid doping and the structural stability of polymers to systematically illustrate modification strategies. Here, we summarize recent advancements in enhancing the nonaqueous proton conduction of HT-PEMs. Various polymer structure modification strategies, including main chain and side group modification, cross-linking, blocking, and branching, are reviewed. Composite approaches of polymer, including compounding with organic porous polymers, filling the inorganic components and modifying with ionic liquids, etc., are also covered in this work. These strategies endow the HT-PEMs with more free volume, nanophase-separated structure, and multi-stage proton transfer channels, which can facilitate the proton transportation and improve their performance. Finally, current challenges and future directions for further enhancements are also outlined. 展开更多
关键词 BENZIMIDAZOLE Nonaqueous proton conduction Free volume Nanophase-separated structure Structure modification
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Complementary memtransistors for neuromorphic computing: How, what and why
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作者 Qi Chen Yue Zhou +4 位作者 Weiwei Xiong Zirui Chen Yasai Wang Xiangshui Miao yuhui he 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期64-80,共17页
Memtransistors in which the source-drain channel conductance can be nonvolatilely manipulated through the gate signals have emerged as promising components for implementing neuromorphic computing.On the other side,it ... Memtransistors in which the source-drain channel conductance can be nonvolatilely manipulated through the gate signals have emerged as promising components for implementing neuromorphic computing.On the other side,it is known that the complementary metal-oxide-semiconductor(CMOS)field effect transistors have played the fundamental role in the modern integrated circuit technology.Therefore,will complementary memtransistors(CMT)also play such a role in the future neuromorphic circuits and chips?In this review,various types of materials and physical mechanisms for constructing CMT(how)are inspected with their merits and need-to-address challenges discussed.Then the unique properties(what)and poten-tial applications of CMT in different learning algorithms/scenarios of spiking neural networks(why)are reviewed,including super-vised rule,reinforcement one,dynamic vision with in-sensor computing,etc.Through exploiting the complementary structure-related novel functions,significant reduction of hardware consuming,enhancement of energy/efficiency ratio and other advan-tages have been gained,illustrating the alluring prospect of design technology co-optimization(DTCO)of CMT towards neuro-morphic computing. 展开更多
关键词 complementary memtransistor neuromorphic computing reward-modulated spike timing-dependent plasticity remote supervise method in-sensor computing
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Effect of slow-release iron fertilizer on iron-deficiency chlorosis, yield and quality of Lilium davidii var.unicolor in a two-year field experiment 被引量:3
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作者 Yang Qiu ZhongKui Xie +5 位作者 XinPing Wang YaJun Wang YuBao Zhang yuhui he WenMei Li WenCong Lv 《Research in Cold and Arid Regions》 CSCD 2018年第5期421-427,共7页
Iron deficiency chlorosis of Lilium davidii var. unicolor is often the case in practice in alkaline soils of northwest region of China. It is difficult to control iron chlorosis because of high cost and short effectiv... Iron deficiency chlorosis of Lilium davidii var. unicolor is often the case in practice in alkaline soils of northwest region of China. It is difficult to control iron chlorosis because of high cost and short effective work time of conventional iron fertilizers. In this study, a 2-year field experiment was conducted to evaluate the effects of two slow-release fertilizers on the suppression of iron deficiency chlorosis, soil chemical properties, and the yield and quality of L. davidii var. unicolor. Results show that both coated slow-release iron fertilizers and embedded slow-release iron fertilizer effectively controlled iron-deficiency chlorosis. The application of slow-release iron fertilizers significantly increased plant height and chlorophyll content of L. davidii var. unicolor at different growth stages. Furthermore, coated iron fertilizer application significantly increased starch, protein, soluble sugar and vitamin C content of L. davidii var. unicolor, and it also significantly improved total amino acid content, with increases in essential amino acids(Trp, Leu, Lys, Phe, Val, and Thr contents) and in nonessential amino acids(Asp, Glu, Cit, Ihs, Acc, Ala, Pro, and Cys contents). It was concluded that application of coated slow-release iron fertilizer could be a promising option for suppression of iron deficiency chlorosis and deserves further study. 展开更多
关键词 slow-release fertilizer iron-deficiency chlorosis Lilium davidii var.unicolor LONG-TERM
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An artificial synapse by superlattice-like phase-change material for low-power brain-inspired computing 被引量:1
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作者 Qing Hu Boyi Dong +5 位作者 Lun Wang Enming Huang Hao Tong yuhui he Ming Xu Xiangshui Miao 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第7期49-54,共6页
Phase-change material(PCM)is generating widespread interest as a new candidate for artificial synapses in bioinspired computer systems.However,the amorphization process of PCM devices tends to be abrupt,unlike continu... Phase-change material(PCM)is generating widespread interest as a new candidate for artificial synapses in bioinspired computer systems.However,the amorphization process of PCM devices tends to be abrupt,unlike continuous synaptic depression.The relatively large power consumption and poor analog behavior of PCM devices greatly limit their applications.Here,we fabricate a GeTe/Sb2Te3 superlattice-like PCM device which allows a progressive RESET process.Our devices feature low-power consumption operation and potential high-density integration,which can effectively simulate biological synaptic characteristics.The programming energy can be further reduced by properly selecting the resistance range and operating method.The fabricated devices are implemented in both artificial neural networks(ANN)and convolutional neural network(CNN)simulations,demonstrating high accuracy in brain-like pattern recognition. 展开更多
关键词 superlattice-like phase-change material artificial synapse low-power consumption
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Tailoring lithium intercalation pathway in 2D van der Waals heterostructure for high-speed edge-contacted floating-gate transistor and artificial synapses 被引量:2
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作者 Jun Yu Jiawei Fu +8 位作者 Hongcheng Ruan Han Wang Yimeng Yu Jinpeng Wang yuhui he Jinsong Wu Fuwei Zhuge Ying Ma Tianyou Zhai 《InfoMat》 SCIE CSCD 2024年第10期53-64,共12页
Local phase transition in transition metal dichalcogenides (TMDCs) by lithiumintercalation enables the fabrication of high-quality contact interfaces in twodimensional(2D) electronic devices. However, controlling the ... Local phase transition in transition metal dichalcogenides (TMDCs) by lithiumintercalation enables the fabrication of high-quality contact interfaces in twodimensional(2D) electronic devices. However, controlling the intercalation oflithium is hitherto challenging in vertically stacked van der Waalsheterostructures (vdWHs) due to the random diffusion of lithium ions in thehetero-interface, which hinders their application for contact engineering of 2DvdWHs devices. Herein, a strategy to restrict the lithium intercalation pathwayin vdWHs is developed by using surface-permeation assisted intercalationwhile sealing all edges, based on which a high-performance edge-contact MoS_(2)vdWHs floating-gate transistor is demonstrated. Our method avoids intercalationfrom edges that are prone to be random but intentionally promotes lithiumintercalation from the top surface. The derived MoS_(2) floating-gatetransistor exhibits improved interface quality and significantly reduced subthresholdswing (SS) from >600 to 100 mV dec^(–1). In addition, ultrafast program/erase performance together with well-distinguished 32 memory statesare demonstrated, making it a promising candidate for low-power artificialsynapses. The study on controlling the lithium intercalation pathways in 2DvdWHs offers a viable route toward high-performance 2D electronics for memoryand neuromorphic computing purposes. 展开更多
关键词 2D vdW heterostructure high-speed floating-gate transistor interlayer lithium intercalation engineering phase-engineered contact
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Effects of gibberellic acid on tiller-bulb number and growth performance of Lilium davidii var. unicolor
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作者 yuhui he ZhongKui Xie +3 位作者 XinPing Liu YaJun Wang YuBao Zhang Yang Qiu 《Research in Cold and Arid Regions》 CSCD 2019年第4期327-334,共8页
Lilium davidii var.unicolor(Lanzhou lily)is an important economic crop in the northwest cold and arid regions of China.Effective regulation of tiller-bulb development and plant growth is the key to improving yield and... Lilium davidii var.unicolor(Lanzhou lily)is an important economic crop in the northwest cold and arid regions of China.Effective regulation of tiller-bulb development and plant growth is the key to improving yield and quality of the lily.This study attempted to evaluate the effect of gibberellic acid(GA3)on tiller-bulb development and plant growth of Lanzhou lily by applying GA3 at various concentrations(0 mg/L,10 mg/L,30 mg/L,60 mg/L,and 100 mg/L)before planting and in the seedling period.Results showed that the 60-mg/L GA3 application had an inhibiting effect on tiller-bulb formation and increased the ratios of single and double bulbs but decreased the ratios of bulbs with three or more tiller bulbs,as com pared to the control(CK)and other GA3 treatments.The difference in flower number did not reach significant levels among the treatments.The tillering-related endogenous hormones IAA(indole-3-acetic acid)and Z(zeatin)content de creased,while IAA/Z increased with the 60-mg/L GA3 treatment during tiller initiation.And also,the shoot-bulb number and total daughter-bulb number decreased significantly with the 60-mg/L GA3 treatment.Furthermore,the 10-mg/L GA3 application promoted growth of Lanzhou lily significantly and resulted in an increase in plant height;bulb diameter;bulb circumference;and biomass of shoots,bulbs,fibrous roots,and the whole plant.Therefore,GA3 application is promising as a new regulation method for inhibiting tiller-bulb development and promoting bulb growth in Lanzhou lily production. 展开更多
关键词 Gibberellic acid TILLER BULB endogenous HORMONE content height biomass
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Multi-Level Regulation of Electrostatic Microenvironment With Anion Vacancies for Low-Lithium-Gradient Polymer Electrolyte
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作者 Yunfa Dong yuhui he +11 位作者 Botao Yuan Xingyu Ding Shijie Zhong Jianze Feng Yupei Han Zhezhi Liu Lin Xu Ke Feng Jiecai Han Haichao Cheng Chade Lv Weidong he 《Electron》 2025年第3期21-30,共10页
Solid-state lithium-metal batteries based on poly(vinylidene fluoride-co-hexafluoropropylene)(PVH)are frequently proposed to address the detrimental safety issue of conventional lithium-ion batteries by eliminating th... Solid-state lithium-metal batteries based on poly(vinylidene fluoride-co-hexafluoropropylene)(PVH)are frequently proposed to address the detrimental safety issue of conventional lithium-ion batteries by eliminating the use of flammable solvents,but still face a key challenge:low capacity and sluggish charge/discharge rate due to the intrinsic large-gradient Li^(+)distribution across the ionically-inert PVH matrix.Herein,Te vacancies in form of Bi_(2)Te_(3-x) are proposed to polarize the PVH unit to realize efficient decoupling of lithium salts at the atomic level in PVH-based solid polymeric electrolyte.Te vacancies in the PVH electrolyte doped with Bi_(2)Te_(3-x)(PVBT)induce a high-throughput and homogenous Li^(+)flow within the PVH matrices and near the Li metal.Theoretical calculations show that Te vacancies own high adsorption energy with bis(trifluoromethanesulfonyl)imide anions(TFSI^(-)),repulsive effect on Li^(+),and localized electron distribution,giving rise to a lithium-ion concentration gradient of 30 mol m^(-3),the smallest among the PVH-based inorganic/organic composite electrolytes.Consequently,the polarized electrolyte owns an unprecedented high-rate battery capacity of 114 mAh g^(-1)at~700 mA g^(-1)and also superior capacity performances with a cathode loading of 12 mg cm^(-2),outperforming the state-of-art PVH-based inorganic/organic composite electrolytes in Li||LiFePO_(4)battery.The work demonstrates an efficient strategy for achieving fast Liþdiffusion dynamics across polymeric matrices of classic solid-state electrolytes. 展开更多
关键词 anion vacancy fast Liþdiffusion PVH matrix solid state electrolyte
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Simulation of inhomogeneous strain in Ge-Si core-shell nanowires
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作者 yuhui he Yuning ZHAO +2 位作者 Chun FAN Xiaoyan LIU Ruqi HAN 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2009年第3期342-347,共6页
This paper studies the elastic deformation field in lattice-mismatched Ge-Si core-shell nanowires(NWs).Infinite wires with a cylindrical cross section under the assumption of translational symmetry are considered.The ... This paper studies the elastic deformation field in lattice-mismatched Ge-Si core-shell nanowires(NWs).Infinite wires with a cylindrical cross section under the assumption of translational symmetry are considered.The strain distributions are found by minimizing the elastic energy per unit cell using finite element method.This paper finds that the trace of the strain is discontinuous with a simple,almost piecewise variation between core and shell,whereas the individual components of the strain can exhibit complex variations.The simulation results are prerequisite of strained band structure calculation,and pave a way for further investigation of strain effect on the related transport property simulation. 展开更多
关键词 core-shell nanowire STRAIN continuum elasticity
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Toward memristive in-memory computing:principles and applications 被引量:2
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作者 Han Bao Houji Zhou +13 位作者 Jiancong Li Huaizhi Pei Jing Tian Ling Yang Shengguang Ren Shaoqin Tong Yi Li yuhui he Jia Chen Yimao Cai Huaqiang Wu Qi Liu Qing Wan Xiangshui Miao 《Frontiers of Optoelectronics》 EI CSCD 2022年第2期101-125,共25页
With the rapid growth of computer science and big data,the traditional von Neumann architecture suffers the aggravating data communication costs due to the separated structure of the processing units and memories.Memr... With the rapid growth of computer science and big data,the traditional von Neumann architecture suffers the aggravating data communication costs due to the separated structure of the processing units and memories.Memristive in-memory computing paradigm is considered as a prominent candidate to address these issues,and plentiful applications have been demonstrated and verified.These applications can be broadly categorized into two major types:soft computing that can tolerant uncertain and imprecise results,and hard computing that emphasizes explicit and precise numerical results for each task,leading to different requirements on the computational accuracies and the corresponding hardware solutions.In this review,we conduct a thorough survey of the recent advances of memristive in-memory computing applications,both on the soft computing type that focuses on artificial neural networks and other machine learning algorithms,and the hard computing type that includes scientific computing and digital image processing.At the end of the review,we discuss the remaining challenges and future opportunities of memristive in-memory computing in the incoming Artificial Intelligence of Things era. 展开更多
关键词 MEMRISTOR In-memory computing Matrix-vector multiplication Machine learning Scientific computing Digital image processing
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基于Ge-Ga-Sb介质的全相变脉冲神经网络的设计 被引量:1
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作者 林俊 麦贤良 +7 位作者 张大友 王宽 王欢 李祎 童浩 何毓辉 徐明 缪向水 《Science China Materials》 SCIE EI CAS CSCD 2023年第4期1551-1558,共8页
人工脉冲神经网络通常由多个异质结构的电路单元构成,其中包括具备积分点火功能来产生脉冲信号的神经元模拟器,以及具备记忆功能的突触器件.在本文中,我们设计了一种能进行“同质集成”的相变存储介质Ge-Ga-Sb(GGS)器件,该器件能够同时... 人工脉冲神经网络通常由多个异质结构的电路单元构成,其中包括具备积分点火功能来产生脉冲信号的神经元模拟器,以及具备记忆功能的突触器件.在本文中,我们设计了一种能进行“同质集成”的相变存储介质Ge-Ga-Sb(GGS)器件,该器件能够同时实现神经元和突触的模拟.在先前的研究中,GGS材料表现出优秀的数据存储功能,例如它具备较高的工作温度(281℃)、较高的十年数据保存温度(230℃)以及较低的电阻漂移.当对该器件改用短脉冲电学操作时,GGS器件首先会发生几个数量级的电阻突变,然后紧接着发生连续的电阻降低.通过透射电子显微镜发现,电阻突变是因为电极之间产生了结晶的导电通道,而电阻缓变是因为导电通道的变粗以及在通道内产生材料分相所致.这种“突变-缓变”的电阻变化特性既可以用来模拟神经元的积分点火功能,也可以模拟突触权重的变化.基于此器件设计的全相变脉冲神经网络,可以实现高达90%的手写数字识别率. 展开更多
关键词 脉冲神经网络 手写数字识别 数据保存 电路单元 电阻突变 导电通道 记忆功能 脉冲信号
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Self-selective memristor-enabled in-memory search for highly efficient data mining 被引量:1
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作者 Ling Yang Xiaodi Huang +12 位作者 Yi Li Houji Zhou Yingjie Yu Han Bao Jiancong Li Shengguang Ren Feng Wang Lei Ye yuhui he Jia Chen Guiyou Pu Xiang Li Xiangshui Miao 《InfoMat》 SCIE CSCD 2023年第5期121-133,共13页
Similarity search,that is,finding similar items in massive data,is a fundamental computing problem in many fields such as data mining and information retrieval.However,for large-scale and high-dimension data,it suffer... Similarity search,that is,finding similar items in massive data,is a fundamental computing problem in many fields such as data mining and information retrieval.However,for large-scale and high-dimension data,it suffers from high computational complexity,requiring tremendous computation resources.Here,based on the low-power self-selective memristors,for the first time,we propose an in-memory search(IMS)system with two innovative designs.First,by exploiting the natural distribution law of the devices resistance,a hardware locality sensitive hashing encoder has been designed to transform the realvalued vectors into more efficient binary codes.Second,a compact memristive ternary content addressable memory is developed to calculate the Hamming distances between the binary codes in parallel.Our IMS system demonstrated a 168energy efficiency improvement over all-transistors counterparts in clustering and classification tasks,while achieving a software-comparable accuracy,thus providing a low-complexity and low-power solution for in-memory data mining applications. 展开更多
关键词 in-memory search self-selective memristor similarity search ternary content addressable memory
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Unified throughout-pore microstructure enables ultrahigh separator porosity for robust high-flux lithium batteries 被引量:2
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作者 Dongjiang Chen Yuanpeng Liu +8 位作者 Chao Feng yuhui he Shengyu Zhou Botao Yuan Yunfa Dong Haodong Xie Guangfeng Zeng Jiecai Han Weidong he 《Electron》 2023年第1期37-49,共13页
With small thickness,commercial polyolefin separators own low porosity to ensure sufficient thermomechanical properties,resulting in tortuous and enlarged Li+diffusion pathways that induce large overpotentials and det... With small thickness,commercial polyolefin separators own low porosity to ensure sufficient thermomechanical properties,resulting in tortuous and enlarged Li+diffusion pathways that induce large overpotentials and detrimental dendrite growth.As a dilemma,the exploration of highly porous separators has been challenged by their large thickness,impairing the applicability of such pursuits.Herein,an ultraporous architecture is designed to shorten Li+transfer pathways by impregnating electrolyteaffinitive poly(vinylidene fluoride-co-hexafluoropropylene)into ultralight~3μm 3D-polytetrafluoroethylene scaffold(abbreviated as UP3D).The UP3D separator with a porosity of 74%gives rise to 70%enhancement in Li+transference and 77%reduction in Li+transfer resistance(2.67 mΩmm^(−1))and thus enables an ultrahigh Li+flux of 22.7 mA cm^(−2),effectively alleviating Li+concentration gradient across the separator.With the separator,the LiFePO4 half cell delivers a capacity of 118 mAh g^(−1) with an unparalleled capacity retention of 90%after 1000 cycles at 2 C,and a graphite||LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)pouch full cell delivers an areal energy density of 6.8 mWh cm^(−2)at 8.848 mA(1.4 mA cm^(−2))with a high cathode loading of 134.9 mg.Such results,together with the scalable production of the separator,reflect its promising potential in high-flux battery applications of separators that require both ultrahigh porosity and reliability. 展开更多
关键词 Li deposition Li-ion batteries polytetrafluoroethylene SEPARATOR ultrahigh porosity
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