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光传输系统中LDPC码的新颖随机构造方法

半导体光电 2014年第6期35卷 1058-1061页

作者：袁建国田杨舒梁博张杰郭旭兵重庆邮电大学光纤通信技术重点实验室重庆400065

分析光传输系统的传输特性与规则LDPC码的随机构造方法之后,提出LDPC码的一种新颖随机构造方法。基于该构造方法构造了一种新颖的码率为93.7%、冗余度为6.69%的规则SCG-LDPC(3969,3720)码,该规则LDPC码在将来的硬件实现中可相对地节省... 详细信息

分析光传输系统的传输特性与规则LDPC码的随机构造方法之后,提出LDPC码的一种新颖随机构造方法。基于该构造方法构造了一种新颖的码率为93.7%、冗余度为6.69%的规则SCG-LDPC(3969,3720)码,该规则LDPC码在将来的硬件实现中可相对地节省硬件存储空间和减少计算量。仿真分析表明:该新颖的SCG-LDPC(3969,3720)码在BER为10-8时,与同码率同冗余度的ITU-T G.975建议中RS(255,239)码和ITU-T G.975.1建议中LDPC(32640,30592)码相比,其净编码增益(NCG)和距离Shannon限都分别改善了约1.92dB和0.97dB。因而该规则LDPC码的纠错性能更为优越,更适用于光传输系统。

关键词：光传输系统随机构造方法前向纠错低密度奇偶校验码净编码增益

南雄自然保护区—城乡梯度空气负离子时空分异对比研究

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热带林业 2021年第4期49卷 9-13页

作者：郭绪兵蔡章林邱治军陈志红周光益广东南雄小流坑—青嶂山省级自然保护区广东南雄512421 中国林业科学研究院热带林业研究所广东广州510520

对比分析广东南雄小流坑-青嶂山自然保护区与城区、乡镇的空气负离子变化特征,探究森林植被对空气负离子的调控作用,为森林旅游资源开发和生态环境建设提供理论支撑。使用空气负离子仪对2019年保护区内外的空气负离子浓度进行实地对比... 详细信息

对比分析广东南雄小流坑-青嶂山自然保护区与城区、乡镇的空气负离子变化特征,探究森林植被对空气负离子的调控作用,为森林旅游资源开发和生态环境建设提供理论支撑。使用空气负离子仪对2019年保护区内外的空气负离子浓度进行实地对比观测和分析。研究结果表明:(1)空气负离子浓度空间分异明显,保护区内空气负离子年平均值为1194 ion·cm^(-3),分别是乡镇和城区的1.5倍和2.8倍;(2)保护区内空气负离子浓度的季节性变化显著,夏季最高,冬季最低,但城区空气负离子的季节性变化不显著;(3)一天之内,空气负离子浓度上午或者傍晚最高,中午最低,下午居中。森林对空气负离子具有明显的调控作用,森林质量越好,空气负离子浓度越高。

关键词：空气质量森林旅游阔叶林时空变化

南雄小流坑——青嶂山保护区维管植物区系研究

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林业与环境科学 2017年第1期33卷 16-23页

作者：陈志红郭绪兵戴文坛陈伟霖王厚麟缪绅裕广东南雄小流坑-青嶂山省级自然保护区广东南雄512421 广州大学生命科学学院广东广州510006

基于历史资料、文献查阅和2016年4—8月的样线、样方补充调查结果显示,广东南雄小流坑—青嶂山省级自然保护区共有野生维管植物1 289种,隶属于185科652属;其中蕨类植物112种,占8.69%,植物区系起源较古老;蕨类植物的科、属地理分布以热... 详细信息

基于历史资料、文献查阅和2016年4—8月的样线、样方补充调查结果显示,广东南雄小流坑—青嶂山省级自然保护区共有野生维管植物1 289种,隶属于185科652属;其中蕨类植物112种,占8.69%,植物区系起源较古老;蕨类植物的科、属地理分布以热带、亚热带为主;种子植物区系表征科为壳斗科、山茶科、樟科、木兰科、金缕梅科、冬青科等共14个科,是华夏植物区系的重要组成部分。种子植物科、属的分布区类型中均以泛热带分布型占优势,同时含有较多的热带亚洲、北温带区系成分,区系成分复杂、多样且古老;区内有国家重点保护和珍稀濒危植物13科14属15种,其中的莼菜(Brasenia schreberi)和南方红豆杉(Taxus wallichiana ***)为国家I级重点保护植物;与邻近的车八岭保护区种子植物区系比较,二者的科、属相似性系数分别为92.86%和77.40%,存在较明显的差异。

关键词：维管植物种子植物区系小流坑-青嶂山自然保护区

A flexible and high temperature tolerant strain sensor of La0.7Sr0.3MnO3/Mica

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Journal of Materials Science & Technology 2020年第9期44卷 42-47页

作者： Min guo Cheng Yang Dong Gao Qiang Li Aihua Zhang Jiajun Feng Hui Yang Ruiqiang Tao Zhen Fan Min Zeng guofu Zhou xubing Lu J-MLiu Institute for Advanced Materials and Guangdong Provincial Key Laboratory of Optical Information Materials and Technology South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Optical Information Materials and Institute of Electronic Paper Displays South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou 510006China National Center for International Research on Green Optoelectronics South China Normal UniversityGuangzhou 510006China Laboratory of Solid State Microstructures and Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

Flexible sensors have been widely investigated due to their broad application prospects in various flexible ***,most of the presently studied flexible sensors are only suitable for working at room temperature,and their applications at high or low temperatures are still a big *** this work,we present a multimodal flexible sensor based on functional oxide La0.7Sr0.3MnO3(LSMO)thin film deposited on mica *** a strain sensor,it shows excellent sensitivity to mechanical bending and high bending durability(up to 3600 cycles).Moreover,the LSMO/Mica sensor also shows a sensitive response to the magnetic field,implying its multimodal sensing *** importantly,it can work in a wide temperature range from extreme low temperature down to 20K to high temperature up to 773 *** flexible sensor based on the flexible LSMO/mica hetero-structure shows great potential applications for flexible electronics using at extreme temperature environment in the future.

关键词： Flexible sensor Mica La0.7Sr0.3MnO3 High temperature Multimodal sensing

Versatile SrFeO_(x) for memristive neurons and synapses

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Journal of Materiomics 2022年第5期8卷 967-975页

作者： Kaihui Chen Zhen Fan Jingjing Rao Wenjie Li Deming Wang Changjian Li Gaokuo Zhong Ruiqiang Tao guo Tian Minghui Qin Min Zeng xubing Lu guofu Zhou Xingsen Gao Jun-Ming Liu Institute for Advanced Materials South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou510006China Guangdong Provincial Key Laboratory of Optical Information Materials and Technology&National Center for International Research on Green Optoelectronics South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou510006China School of Physics and Telecommunication Engineering South China Normal UniversityGuangzhou510006China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen518055China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen518055China Laboratory of Solid State Microstructures and Innovation Center of Advanced Microstructures Nanjing UniversityNanjing210093China

Spiking neural network(SNN)consisting of memristor-based artificial neurons and synapses has emerged as a compact and energy-efficient hardware solution for spatiotemporal information ***,it is challenging to develop memristive neurons and synapses based on the same material system because the required resistive switching(RS)characteristics are ***,it is shown that SrFeO_(x)(SFO),an intriguing material system exhibiting topotactic phase transformation between insulating brownmillerite(BM)SrFeO_(2).5 phase and conductive perovskite(PV)SrFeO_(3) phase,can be engineered into both neuronal and synaptic *** a BM-SFO single layer as the RS medium,the Au/BM-SFO/SrRuO_(3)(SRO)memristor exhibits nonvolatile RS behavior originating from the formation/rupture of PV-SFO filaments in the BM-SFO *** contrast,using a PV-SFO(matrix)/BM-SFO(interfacial layer)bilayer as the RS medium,the Au/PV-SFO/BM-SFO/SRO memristor exhibits volatile RS behavior originating from the interfacial BM-PV phase *** and neuronal characteristics are further demonstrated in the Au/BM-SFO/SRO and Au/PV-SFO/BM-SFO/SRO memristors,*** the SFO-based synapses and neurons,fully memristive SNNs are constructed by simulation,which show good performance on unsupervised image *** study suggests that SFO is a versatile material platform on which both neuronal and synaptic devices can be developed for constructing fully memristive SNNs.

关键词： Memristors Artificial synapses Artificial neurons Spiking neural network SrFeO_(x)

Experimental search for high-performance ferroelectric tunnel junctions guided by machine learning

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Journal of Advanced Dielectrics 2022年第3期12卷 35-47页

作者： Jingjing Rao Zhen Fan Qicheng Huang Yongjian Luo Xingmin Zhang Haizhong guo Xiaobing Yan guo Tian Deyang Chen Zhipeng Hou Minghui Qin Min Zeng xubing Lu guofu Zhou Xingsen Gao Jun-Ming Liu Institute for Advanced Materials South China Normal UniversityGuangzhou 510006P.R.China Guangdong Provincial Key Laboratory of Optical Information Materials and Technology South China Normal University Guangzhou 510006P.R.China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204P.R.China§School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001P.R.China Key Laboratory of Brain-Like Neuromorphic Devices and Systems of Hebei Province Hebei University Baoding 071002P.R.China Laboratory of Solid State Microstructures and Innovation Center of Advanced Nanjing 210093P.R.China

Ferroelectric tunnel junction(FTJ)has attracted considerable attention for its potential applications in nonvolatile memory and neuromorphic ***,the experimental exploration of FTJs with high ON/OFF ratios is a challenging task due to the vast search space comprising of ferroelectric and electrode materials,fabrication methods and conditions and so ***,machine learning(ML)is demonstrated to be an effective tool to guide the experimental search of FTJs with high ON/OFF ratios.A dataset consisting of 152 FTJ samples with nine features and one target attribute(i.e.,ON/OFF ratio)is established for ML *** various ML models,the gradient boosting classification model achieves the highest prediction *** the feature importance analysis based on this model with the association rule mining,it is extracted that the utilizations of{graphene/graphite(Gra)(top),LaNiO_(3)(LNO)(bottom)}and{Gra(top),Ca_(0.96)Ce_(0.04)MnO_(3)(CCMO)(bottom)}electrode pairs are likely to result in high ON/OFF ratios in ***,two previously unexplored FTJs:Gra/BaTiO_(3)(BTO)/LNO and Gra/BTO/CCMO,are predicted to achieve ON/OFF ratios higher than *** by the ML predictions,the Gra/BTO/LNO and Gra/BTO/CCMO FTJs are experimentally fabricated,which unsurprisingly exhibit≥1000 ON/OFF ratios(~8540 and~7890,respectively).This study demonstrates a new paradigm of developing high-performance FTJs by using ML.

关键词： Machine learning ferroelectric tunnel junctions ON/OFF ratio nonvolatile memory

The Design and Synthesis of Aromatic Spiroketal Bisphosphine Ligands（SKP） and Their Applications in Asymmetric Catalytic Reactions

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The Design and Synthesis of Aromatic Spiroketal Bisphosphine...

Impact of annealing temperature on the ferroelectric properties of W/Hf_(0.5)Zr_(0.5)O_(2)/W capacitor

第十八届全国金属有机化学学术研讨会

作者： Xiaoming Wang Zhaobin Han xubing Wang Fanye Meng Peihua guo Changsen Wei Zheng Wang Kuiling Ding State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences

＜正＞The development of new methodologies for efficient synthesis of chiral backbones will be highly valuable for the exploration of novel and highly selective chiral ligands,which play a key role in asymmetric catalytic *** the present work,a class of chiral aromatic spiroketal compounds were efficiently synthesized in excellent enantiopurities via Ir catalyzed asymmetric hydrogenation and spiroketalization,which constitutes the first catalytic asymmetric synthesis of this kind of structures.

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中国物理B:英文版 2023年第9期32卷 492-497页

作者：王岛张岩郭永斌尚真真符方健陆旭兵 College of Science Qiongtai Normal UniversityKey Laboratory of Child Cognition and Behavior Development of Hainan ProvinceHaikou 571127China College of Electronic and Electrical Engineering Henan Normal UniversityXinxiang 453007China Institute for Advanced Materials and Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou 510006China Key Laboratory of UWB and THz of Shandong Academy of Sciences Institute of AutomationQilu University of TechnologyJinan 250014China

Crystallization annealing is a crucial process for the formation of the ferroelectric phase in HfO_(2)-based ferroelectric thin ***,we systematically investigate the impact of the annealing process,with temperature varied from 350℃to 550℃,on the electricity,ferroelectricity and reliability of a Hf_(0.5)Zr_(0.5)O_(2)(HZO;7.5 nm)film *** was found that HZO film annealed at a low temperature of 400℃can effectively suppress the formation of the monoclinic phase and reduce the leakage *** film annealed at 400℃also exhibits better ferroelectric properties than those annealed at 350℃and 550℃.Specifically,the 400℃-annealed HZO film shows an outstanding 2Pr value of 54.6μC·cm^(-2)at±3.0 MV·cm^(-1),which is relatively high compared with previously reported values for HZO film under the same electric field and annealing *** the applied electric field increases to±5.0 MV·cm^(-1),the 2Pr value can reach a maximum of 69.6μC·cm^(-2).In addition,the HZO films annealed at 400℃and 550℃can endure up to bout 2.3×10^(8)cycles under a cycling field of 2.0 MV·cm^(-1)before the occurrence of *** the 400℃-annealed HZO film,72.1%of the initial polarization is maintained while only 44.9%is maintained in the 550℃-annealed HZO *** work demonstrates that HZO film with a low crystallization temperature(400℃)has quite a high ferroelectric polarization,which is of significant importance in applications in ferroelectric memory and negative capacitance transistors.

关键词： Hf_(0.5)Zr_(0.5)O_(2)thin film annealing temperature ferroelectric polarization endurance

酸枣根系结构可塑性对自然梯度干旱生境的适应机制

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生态学报 2018年第16期38卷 5810-5818页

作者：朱广龙陈许兵郭小倩焦秀荣周桂生扬州大学农业科技发展研究院教育部农业与农产品安全国际合作联合实验室扬州225009

根系是植物吸收水分和养分的主要器官,是直接接触土壤最先感受土壤逆境胁迫的部位。在干旱环境中,植物根系的结构特征必定发生改变以维持正常的生物机能而生存。目前,关于根系解剖结构的研究大多集中于根系的某一特定结构对单一逆境因... 详细信息

根系是植物吸收水分和养分的主要器官,是直接接触土壤最先感受土壤逆境胁迫的部位。在干旱环境中,植物根系的结构特征必定发生改变以维持正常的生物机能而生存。目前,关于根系解剖结构的研究大多集中于根系的某一特定结构对单一逆境因子的响应。以生长在烟台-石家庄-银川-吐鲁番不同地域气候条件形成的自然梯度干旱环境中的酸枣为试验材料,应用植物显微技术研究酸根系结构的可塑性对不同自然梯度干旱环境的适应机制,结果表明:酸枣根的初生结构包括表皮、皮层和维管柱,表皮位于幼根的最外层,由单层体积较小、紧密排列的表皮细胞组成。皮层占根初生结构的大部分比例,由体积较大的多层薄壁细胞组成,薄壁细胞近似圆球形,数目众多,呈环形分布。维管柱位于最内层,细胞小而密集,由中柱鞘、初生木质部、初生韧皮部及薄壁细胞组成。随生境干旱加剧,酸枣根初生结构表皮细胞的厚度和宽度逐渐增加,皮层薄壁细胞的厚度和宽度、皮层薄壁细胞层数和皮层厚度均以宁夏银川样地的最大。酸枣根的次生结构包括周皮(木栓层、木栓形成层、栓内层)和次生维管组织(次生韧皮部、维管形成层和次生木质部)。从烟台至新疆吐鲁番随生境干旱加剧,酸枣植株根系周皮逐渐加厚、致密度提高。次生木质部中,导管的数量增加,管径增大。干旱环境中,酸枣植株根系结构上的变化一方面提高了吸水能力和输水效率,另一方面增强了保水能力,减少水分散失,这可能是其适应干旱逆境的机制之一。

关键词：酸枣根系可塑性梯度干旱生境适应机制