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A Novel Feature-based Method for Sentiment Analysis of Chinese Product Reviews

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China Communications 2014年第3期11卷 154-164页

作者： liu lizhen SONG Wei WANG Hanshi LI Chuchu LU Jingli Information and Engineering College Capital Normal University Beijing 100048 P. R. China Agresearch Ltd New Zealand

Sentiment analysis of online reviews and other user generated content is an important research problem for its wide range of *** this paper,we propose a feature-based vector model and a novel weighting algorithm for sentiment analysis of Chinese product ***,an opinionated document is modeled by a set of feature-based vectors and corresponding *** from previous work,our model considers modifying relationships between words and contains rich sentiment strength descriptions which are represented by adverbs of degree and *** parsing is applied to construct the feature vectors.A novel feature weighting algorithm is proposed for supervised sentiment classification based on rich sentiment strength related *** experimental results demonstrate the effectiveness of the proposed method compared with a state of the art method using term level weighting algorithms.

关键词：基于特征情感评论商品中国加权算法向量模型特征向量

An Improved Unsupervised Approach to Word Segmentation

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China Communications 2015年第7期12卷 82-95页

作者： WANG Hanshi HAN Xuhong liu lizhen SONG Wei YUAN Mudan Information and Engineering College Capital Normal University Beijing Bayi High School

ESA is an unsupervised approach to word segmentation previously proposed by Wang, which is an iterative process consisting of three phases: Evaluation, Selection and Adjustment. In this article, we propose Ex ESA, the extension of ESA. In Ex ESA, the original approach is extended to a 2-pass process and the ratio of different word lengths is introduced as the third type of information combined with cohesion and separation. A maximum strategy is adopted to determine the best segmentation of a character sequence in the phrase of Selection. Besides, in Adjustment, Ex ESA re-evaluates separation information and individual information to overcome the overestimation frequencies. Additionally, a smoothing algorithm is applied to alleviate sparseness. The experiment results show that Ex ESA can further improve the performance and is time-saving by properly utilizing more information from un-annotated corpora. Moreover, the parameters of Ex ESA can be predicted by a set of empirical formulae or combined with the minimum description length principle.

关键词：分词方法监督个人信息最小描述长度 ESA 平滑算法合理利用经验公式

干湿交替对湖泊沉积物中磷的形态及释放速率影响

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人民长江 2024年第2期55卷 57-64,76页

作者：吴虎彬李荣富吴永明姚忠刘亚军刘丽贞南昌大学资源与环境学院江西南昌330031 江西省科学院微生物研究所江西南昌330096

沉积物是湖泊水环境磷的重要内源,由于气候变化和人类活动的影响,鄱阳湖季节性水位波动剧烈,这种季节性干湿交替对沉积物磷的内源释放的影响目前尚不明确。选择鄱阳湖抚河入湖口为研究对象,采集了6根粉砂壤土沉积柱与6根砂土沉积柱,室... 详细信息

沉积物是湖泊水环境磷的重要内源,由于气候变化和人类活动的影响,鄱阳湖季节性水位波动剧烈,这种季节性干湿交替对沉积物磷的内源释放的影响目前尚不明确。选择鄱阳湖抚河入湖口为研究对象,采集了6根粉砂壤土沉积柱与6根砂土沉积柱,室内模拟干湿交替及长期淹水两种情景并开展了45 d的培养试验,探讨了干湿交替对沉积物磷的形态与内源释放速率的影响。结果表明:(1)干湿交替促进沉积物向上覆水释放磷,释放磷的主要组分为有机磷,粉砂壤土与砂土沉积物总磷释放速率最大可达2.59 mg/(m^(2)·d)与1.97 mg/(m^(2)·d),是长期淹水沉积物总磷释放速率的4~5倍;(2)干湿交替条件下沉积物中铁铝结合态无机磷(Fe/Al-Pi)减少,弱吸附态无机磷(WA-Pi)、潜在活性有机磷(PA-Po)等易释放的磷含量增加,中活性有机磷(MA-Po)增加,钙结合态无机磷(Ca-Pi)、非活性有机磷(NA-Po)等较稳定的磷无显著变化;(3)长期淹水沉积物中Fe/Al-Pi增加,与Fe/Al-Pi能够相互转化的MA-Po减小,易释放的磷(WA-Pi、PA-Pi、PA-Po)及较稳定的磷(Ca-Pi、NA-Po)无显著变化。分析表明干湿交替条件会促进Fe/Al-Pi向MA-Po转化,并进一步转化为易释放的WA-P、PA-Po,促进底泥内源磷释放。

关键词：沉积物磷形态内源释放干湿交替鄱阳湖

High proton conductivity in metalloring-cluster based metalorganic nanotubes

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Nano Research 2021年第2期14卷 387-391页

作者： Quanjie Lin Yingxiang Ye lizhen liu Zizhu Yao Ziyin Li Lihua Wang Chulong liu Zhangjing Zhang Shengchang Xiang Fujian Provincial Key Laboratory of Polymer Materials College of Chemistry and Materials ScienceFujian Normal Uriversity32 Shangsan RoadFuzhou 350007China State Key Laboratory of Structural Chemistry Frujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Two novel anionic single-walled metal-organic nanotubes(MONTs),[(CH_(3))_(2)NH_(2)][ln(cdc)(thb)].2DMF.9.5H_(2)O(FJU-105)and[(CH_(3))_(2)NH_(2)][ln(cdc)(H-btc)]-2DMA·11H_(2)O(FJU-106)(H_(2)cdc=9H-carbazole-3,6-dicarboxylic acid,H_(2)thb=2,5-thiophene dicarboxylic acid,H3btc=1,3,5-benzene tricarboxylic acid),are achieved by employing[ln_(6)(cdc)_(6)]^(6+)metalloring cluster with largest diameter as the secondary building blocks(SBUs).The inner surface of FJU-106 is functionalized by uncoordinated-COOH groups of the H-btc linkers,leading to a higher proton conduction than *** 70℃,FJU-106 displays the proton conduction performances among MONTs,up to 1.80×10^(-2)S·cm(^-1).And FJU-105 and FJU-106 are the first examples of MONT proton conductors operating at subzero temperature.

关键词： metal-organic nanotubes macrocyclic metalloring cluster inner-surface functionalizatin proton-conductivity

Extraction and characterization of bound extracellular polymeric substances from cultured pure cyanobacterium(Microcystis wesenbergii)

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Journal of Environmental Sciences 2014年第8期26卷 1725-1732页

作者： lizhen liu Boqiang Qin Yunlin Zhang Guangwei Zhu Guang Gao Qi Huang Xin Yao State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography & LimnologyChinese Academy of Sciences University of Chinese Academy of Sciences School of Environment and Planning Liaocheng University

Preliminary characterization of bound extracellular polymeric substances（bEPS） of cyanobacteria is crucial to obtain a better understanding of the formation mechanism of cyanobacterial bloom. However,the characterization of bEPS can be affected by extraction methods. Five sets（including the control） of bEPS from Microcystis extracted by different methods were characterized using three-dimensional excitation and emission matrix（3DEEM） fluorescence spectroscopy combined chemical spectrophotometry; and the characterization results of bEPS samples were further compared. The agents used for extraction were NaOH,pure water and phosphate buffered saline（PBS） containing cationic exchange resins,and hot water. Extraction methods affected the fluorescence signals and intensities in the bEPS. Five fluorescence peaks were observed in the excitation and emission matrix fluorescence spectra of bEPS samples. Two peaks（peaks T1 and T2） present in all extractions were identified as protein-like fluorophores,two（peaks A and C） as humic-like fluorophores,and one（peak E） as a fulvic-like *** these substances,the humic-like and fulvic-like fluorescences were only seen in the bEPS extracted with hot water. Also,NaOH solution extraction could result in strong fluorescence intensities compared to the other extraction methods. It was suggested that NaOH at pH 10.0 was the most appropriate method to extract bEPS from Microcystis. In addition,dialysis could affect the yields and characteristics of extracted bEPS during the determination process. These results will help us to explore the issues of cyanobacterial blooms.

关键词： Bound extracellular polymeric substances(bEPS) Extraction Fluorescence intensities Microcystis Three-dimensional excitation and emission matrix(3DEEM)

Layer-by-layer epitaxy growth of thickness-controllable two-dimensional tungsten disulfide

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Science China(Information Sciences) 2024年第5期67卷 302-310页

作者： Jieyuan LIANG Zixing ZOU Junwu LIANG Di WANG Biao WANG Anshi CHU Jiali YI Cheng ZHANG lizhen FANG Tian ZHANG Huawei liu Xiaoli ZHU Dong LI Anlian PAN Key Laboratory for Micro-Nano Physics and Technology of Hunan Province State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan Institute of Optoelectronic IntegrationCollege of Materials Science and Engineering School of Physics and ElectronicsHunan University School of Electronic Information and Electrical Engineering Changsha University School of Physics and Telecommunication Engineering Yulin Normal University Units Semiconductor Technology Co. Ltd. School of Physics and Electronics Hunan Normal University

Bilayer transition metal dichalcogenides（TMDs） balance the high mobility of single layers with the high state density of multilayers and therefore have promising application prospects in high-performance electronics. However, the layer-controlled growth of 2D materials is still confronted with challenges such as poor repeatability between different labs and a limited understanding of the growth mechanism at the atomic scale. Herein, we report a new carbon-assisted chemical vapor deposition process that can realize the growth of WS2sheets with high yield, precise thickness controllability, and repeatability. We show that carbon can act as a reducing agent and catalyst that preferentially reacts with the WO3precursor to form intermediate WO3-xproducts with low-valence state W. The resulting oxycarbide gas has a low surface adsorption energy when deposited on the surface of as-grown WS2, which provides nucleation sites for the subsequent layer of WS2growth and leads to the vertical growth of WS2sheets. The growth mechanism is thoroughly investigated. Electrical transport measurements show that the produced bilayer WS2possesses a high carrier mobility(up to 58 cm2·V-1·s-1) and small subthreshold swing（estimated to be 148 mV/decade）,which are among the best reported results for TMDs produced using CVD.

关键词： WS$_2$ thickness-controlled growth chemical vapor deposition additive carbon

Controlled growth of vertically stacked In_(2)Se_(3)/WSe_(2) heterostructures for ultrahigh responsivity photodetector

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Nano Research 2024年第3期17卷 1856-1863页

作者： Cheng Zhang Biyuan Zheng Guangcheng Wu Xueying liu Jiaxin Wu Chengdong Yao Yizhe Wang Zilan Tang Ying Chen lizhen Fang Luying Huang Dong Li Shengman Li Anlian Pan Key Laboratory for Micro-Nano Physics and Technology of Hunan Province State Key Laboratory of Chemo/Biosensing and ChemometricsCollege of Materials Science and EngineeringHunan UniversityChangsha 410082China

Transition metal dichalcogenides(TMDCs)are promising candidates for future optoelectronic devices accounting for their high carrier mobility and excellent quantum ***,the limited light absorption efficiency in atomically thin layers significantly hinders photocarrier generation,thereby impairing the optoelectronic performance and hindering practical ***,we successfully synthesized In_(2)Se_(3)/WSe_(2) heterostructures through a typical two-step chemical vapor deposition(CVD)*** In_(2)Se_(3) nanosheet with strong light absorption capability,serving as the light absorption layer,was integrated with the monolayer WSe_(2),enhancing the photosensitivity of WSe_(2) *** laser irradiation with a wavelength of 520 nm,the In_(2)Se_(3)/WSe_(2) heterostructure device shows an ultrahigh photoresponsivity with a value as high as 2333.5 A/W and a remarkable detectivity reaching up to 6.7×10^(12) Jones,which is the highest among almost the reported TMDCs-based heterostructures grown via CVD even some fabricated by mechanical exfoliation(ME).Combing the advantages of CVD method such as large scale,high yield,and clean interface,the In_(2)Se_(3)/WSe_(2) heterostructures would provide a novel path for future high-performance optoelectronic device.

关键词： transition metal dichalcogenides(TMDCs) In_(2)Se_(3) heterostructure photodetector ultrahigh responsivity

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小型化窄条形宽带柔性天线

固体电子学研究与进展 2023年第5期43卷 408-412页

作者：刘丽珍郑州联睿电子科技有限公司郑州450001

设计了一款小型化窄条形宽带柔性天线,该天线由辐射片和带有短路枝节的共面波导金属地构成,整体尺寸为24.5 mm×5.0 mm×0.1 mm。通过采用带有短路枝节的共面波导金属地、新共面波导结构、两个U型缝隙、馈线倾斜焊接等方法,有效增加了... 详细信息

设计了一款小型化窄条形宽带柔性天线,该天线由辐射片和带有短路枝节的共面波导金属地构成,整体尺寸为24.5 mm×5.0 mm×0.1 mm。通过采用带有短路枝节的共面波导金属地、新共面波导结构、两个U型缝隙、馈线倾斜焊接等方法,有效增加了阻抗带宽,且与常规柔性天线相比尺寸减小70%。测试结果表明,天线用于超宽带定位系统中的智能手表时,工作频段覆盖3.27~4.55 GHz,带宽内增益大于2.4 dBi,不圆度小于0.95 dB。

关键词：小型化窄条形柔性天线智能手表

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农作物种子纠纷的司法调解路径

分子植物育种 2023年第21期21卷 7257-7261页

作者：刘丽珍广州商学院广州511363

本研究对农作物种子纠纷的司法调解路径进行了深入分析,探讨了农作物种子纠纷的多样性和复杂性,并阐述了司法调解在处理这些纠纷中的重要作用。本研究通过案例分析,总结了成功调解的关键因素和经验,并指出了在实际操作中可能遇到的挑战... 详细信息

本研究对农作物种子纠纷的司法调解路径进行了深入分析,探讨了农作物种子纠纷的多样性和复杂性,并阐述了司法调解在处理这些纠纷中的重要作用。本研究通过案例分析,总结了成功调解的关键因素和经验,并指出了在实际操作中可能遇到的挑战。研究还提出了未来如何更有效地进行司法调解的策略和建议,包括深化案例研究、探索技术手段、加强调解员培训、建立多方合作机制和完善法律框架等。本研究期望能为处理农作物种子纠纷提供理论指导和实践参考。

关键词：农作物种子司法调解案例分析合作机制法律框架