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Design and Characterization of a Novel Z-axis Quartz Cross-fork Micromachined Gyroscope

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Chinese Journal of Mechanical Engineering 2011年第1期24卷 50-57页

作者： xie liqiang WU Xuezhong LI Shengyi WANG Haoxu TAO Yi DONG Peitao College of Mechatronics Engineering andAutomation National University of Defense Technology Changsha 410073 China Engineering Institute of Engineering Corps PLA University of Science and Technology Nanjing 210007 China Wuhan Ordnance N. C. O. Academy Wuhan 430075 China

The existing researches on quartz gyroscope mainly focus on the structure design of the tuning fork, which aim at obtaining a better vibration characterization. However, the fabrication of complicated structure is a challenge for present processes, and the imperfect fabrication process seriously affects the performances of the sensors. In this paper, a novel quartz cross-fork structure micromachined gyroscope is proposed. The sensor has a simple structure in x-y plane of quartz crystal. Unlike other quartz gyroscopes, the proposed gyroscope is based on shear stress detection to sense Coriolis’ force rather than normal stress detection. This feature can simplify the sensing electrode patterns and miniaturize the structure easily. Then the mechanical analysis of the structure is discussed. In order to obtain high sensitivities and uniform characteristics between different structures, the sensing beam is designed to be tapered, and the taper should be appreciably greater than 1°. This scheme is validated by finite element analysis software. The dynamic characteristic of the structure is analyzed by lumped parameter model. The dynamic stress in the beam and the detection sensitivity are deduced to optimize the structure parameter of gyroscope. Finally, the gyroscope is fabricated by quartz anisotropic wet etching. The prototype is characterized as follows. The drive mode frequency is 13.38 kHz, and the quality factor is about 900 in air. The scale factor is 1.45 mV/（（°） s –1 ） and the nonlinearity is 3.6% in the dynamic range of ±200°/s. Process and test results show that the proposed quartz gyroscope can achieve a high performance at atmosphere pressure. The research can simplify the fabrication of the quartz gyroscope, and is taken as a novel method for the design of quartz gyroscope.

关键词： quartz gyroscope cross-fork dynamic analysis Coriolis’ force

Risk assessment and identification of factors influencing the historical concentrations of microcystin in Lake Taihu, China

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Journal of Environmental Sciences 2023年第5期127卷 1-14页

作者： Chen Cheng Alan D.Steinman Kaiye Zhang Qi Lin Qingju Xue Xing Wang liqiang xie State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China Annis Water Resources Institute Grand Valley State University740 West Shoreline DriveMuskegonMIUSA National Engineering Laboratory for Lake Pollution Control and Ecological Restoration Chinese Research Academy of Environmental SciencesBeijing 100012China State Environmental Protection Key Laboratory of Drinking Water Source Protection Chinese Research Academy of Environmental SciencesBeijing 100012China

Understanding the history of microcystins(MCs)pollution in large lakes can help inform future lake *** collected sediment cores from Lake Taihu to:investigate the long-term record of MCs(MC-LR,MC-YR,and MC-RR),explore the main environmental drivers of MCs,and assess their public health and ecological *** showed that MCs content in all cores increased over *** core from north Taihu had the highest MC concentrations,with an average total MCs(sum of MC-LR,MC-YR,and MC-RR=TMCs)content of(74.31±328.55)ng/*** core from eastern Taihu showed the lowest average TMCs content of(2.91±3.95)ng/*** showed that sediment MCs at the three sites were positively correlated with sediment ***-LR and MC-YR in northern and western Taihu negatively correlated with both the sediment total organic carbon/sediment total nitrogen ratio(STOC/STN)andwater nitrate(NO_(3)^(−)-N)concentration,but three MC congeners at eastern Taihu showed positive correlations with water orthophosphate(PO_(4)^(3−)-P),NO_(3)^(−)-N,and STOC/*** additive model analysis at each site revealed that NO_(3)^(−)-N was the main TMCs driver in northern andwestern Taihuwhere phytoplankton dominated,whereasPO_(4)^(3−)-P was the main TMCs driver in eastern Taihu where macrophytes *** the whole lake scale,total phosphorus(TP)andPO_(4)^(3−)-P were the most important environmental drivers influencing MCs;TP explained 47.4%,44.2%,and 47.6%while orthophosphate explained 34.8%,31.2%,and 34.7%of the deviance on TMCs,MC-LR,and MC-YR,***_(3)^(−)-N also showed a strong effect on MCs variation,especially on *** assess-ment showed that both ecological and public health risk has increased in recent *** conclude that while control of phosphorus and nitrogen input should be a major focus for future lake management,lake zone-specificmanagement strategiesmay also be important.

关键词： Microcystins Pollution history Orthophosphate Nitrate Risk assessment Lake Taihu

Chlorofullerene C_(60)Cl_(6) Enables Efficient and Stable Tin-Based Perovskite Solar Cells

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Energy & Environmental Materials 2024年第1期7卷 176-183页

作者： Jingfu Chen Chengbo Tian Chao Sun Panpan Yang Wenjing Feng Lingfang Zheng Liu Yang Enlong Hou Jiefeng Luo liqiang xie Zhanhua Wei Xiamen Key Laboratory of Optoelectronic Materials and Advanced Manufacturing Institute of Luminescent Materials and Information DisplaysCollege of Materials Science and EngineeringHuaqiao UniversityXiamen 361021China

Tin-based perovskite solar cells(TPSCs)have received great attention due to their eco-friendly properties and high theoretical ***,the fast crystallization feature of tin-based perovskites leads to poor film quality and limits the corresponding device ***,a chlorofullerene,C_(60)Cl_(6),with six chlorine attached to the C_(60)cage,is applied to modulate the crystallization process and passivate grain boundary defects of the perovskite *** chemical interactions between C_(60)Cl_(6)and perovskite components retard the transforming process of precursors to perovskite crystals and obtain a high-quality tin-based perovskite *** is also revealed that the C_(60)Cl_(6)located at the surfaces and grain boundaries can not only passivate the defects but also offer a role in suturing grain boundaries to suppress the detrimental effects of water and oxygen on perovskite films,especially the oxidation of Sn^(2+)to Sn^(4+).As a result,the C_(60)Cl_(6)-based device yields a remarkably improved device efficiency from 10.03%to 13.30%with enhanced *** work provides a new strategy to regulate the film quality and stability of TPSCs using functional fullerene materials.

关键词： crystallization regulation defect passivation fullerene derivative perovskites solar cell tin-based perovskite

A New Model for Software Defect Prediction Using Particle Swarm Optimization and Support Vector Machine

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A New Model for Software Defect Prediction Using Particle Sw...

第25届中国控制与决策会议

作者： He Can Xing Jianchun Zhu Ruide Li Juelong Yang Qiliang xie liqiang PLA University of Science and Technology Technical Management Office of Naval Defence Engineering

ISBN: (纸本)9781467355339

Software defect prediction could improve the reliability of software and reduce development costs. Traditional prediction models usually have a lower prediction accuracy. In order to solve this problem, a new model for software defect prediction using Particle Swarm Optimization（PSO） and Support Vector Machine（SVM） named P-SVM model is proposed in this paper, which takes advantage of non-linear computing capability of SVM and parameters optimization capability of PSO. Firstly, P-SVM model uses PSO algorithm to calculate the best parameters of SVM, and then it adoptes the optimized SVM model to predict software defect. P-SVM model and other three different prediction models are used to predict the software defects in JM1 data set as an experiment, the results show that P-SVM model has a higher prediction accuracy than BP Neural Network model, SVM model, GA-SVM model.

关键词： software defect prediction Support Vector Machine Particle Swarm Optimization parameters optimization.

来源： cnki会议评论

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高亏格膜泡形状的数值计算

计算物理 2009年第5期26卷 763-766页

作者：解立强甘肃民族师范学院物理系甘肃合作747000

通过对Willmore区域外,特别是中等及较小约化体积下的形状及其演化进行深入细致的研究,发现在这一区域的形状要远比原有的猜测丰富,亏格g=2的膜泡会展现出比已有结果更多迷人的形状并出现新的膜泡相变分支.同时,数值计算的结果更加期待... 详细信息

通过对Willmore区域外,特别是中等及较小约化体积下的形状及其演化进行深入细致的研究,发现在这一区域的形状要远比原有的猜测丰富,亏格g=2的膜泡会展现出比已有结果更多迷人的形状并出现新的膜泡相变分支.同时,数值计算的结果更加期待实验验证,从而为曲率模型的正确性提供有力支持.

关键词：高亏格膜泡形状曲率模型对称性相变

Stabilizing semi-transparent perovskite solar cells with a polymer composite hole transport layer

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Nano Research 2024年第3期17卷 1500-1507页

作者： Yongbin Jin Huiping Feng Zheng Fang Liu Yang Kaikai Liu Bingru Deng Jingfu Chen Xueling Chen Yawen Zhong Jinxin Yang Chengbo Tian liqiang xie Zhanhua Wei Xiamen Key Laboratory of Optoelectronic Materials and Advanced Manufacturing Institute of Luminescent Materials and Information DisplaysCollege of Materials Science and EngineeringHuaqiao UniversityXiamen 361021China

Semi-transparent perovskite solar cells(ST-PSCs)have broad applications in building integrated ***,the stability of ST-PSCs needs to be improved,especially in n-i-p ST-PSCs since the doped 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenyl-amine)-9,9'-spirobifluorene(Spiro-OMeTAD)is unstable at elevated temperatures and high *** this work,aπ-conjugated polymer poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophene-2-yl)-benzo[1,2-b:4,5-b']dithiophene))-alt-(5,5-(1',3'-di-2-thienyl-5',7'-bis(2-ethylhexyl)benzo[1',2'-c:4',5'-c']dithiophene-4,8-dione)](PBDB-T)is selected to form a polymer composite hole transport layer(HTL)with *** sulfur atom of the thiophene unit and the carbonyl group of the polymer interact with the undercoordinated Pb2+at the perovskite surface,which stabilizes the perovskite/HTL interface and passivates the interfacial *** incorporation of the polymer also increases the glass transition temperature and the moisture resistance of *** a result,we obtain ST-PSCs with a champion efficiency of 13.71%and an average visible light transmittance of 36.04%.Therefore,a high light utilization efficiency of 4.94%can be ***,the encapsulated device can maintain 84%of the initial efficiency after 751 h under continuous one-sun illumination(at 30%relative humidity)at the open circuit and the unencapsulated device can maintain 80%of the initial efficiency after maximum power tracking for more than 1250 h under continuous one-sun illumination.

关键词： semi-transparent solar cells π-conjugated polymer composite hole transport layer building integrated photovoltaics

Monolithic bilayered In_(2)O_(3) as an efficient interfacial material for high-performance perovskite solar cells

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Interdisciplinary Materials 2022年第4期1卷 526-536页

作者： Wanjia Tian Peiquan Song Yaping Zhao Lina Shen Kaikai Liu Lingfang Zheng Yujie Luo Chengbo Tian liqiang xie Zhanhua Wei Xiamen Key Laboratory of Optoelectronic Materials and Advanced Manufacturing Institute of Luminescent Materials and Information DisplaysCollege of Materials Science and EngineeringHuaqiao UniversityXiamenPeople's Republic of China

Carrier recombination at the buried SnO_(2)/perovskite interface limits the efficiency and stability of n-i-p-structured perovskite solar cells(PSCs).Herein,we report an In_(2)O_(3)interfacial layer with the distinctive structure of the monolithic compact/nanostructured *** partial hydrolysis nature of the In^(3+)ion enables the formation of nanorods on top of the compact In_(2)O_(3)layer when spin-coating the In(NO_(3))_(3) aqueous *** novel interfacial layer reduces the pinholes of the SnO_(2)film and increases the contact area between the perovskite and electron transport ***,PSCs with the incorporation of the interfacial layer demonstrate enhanced electron extraction and suppressed carrier ***,the champion device achieves a power conversion efficiency of 23.87%with a high fill factor of 82.14%.The optimized device also shows robust operational stability,retaining over 80%of the initial power conversion efficiency after working at the maximum power point for over 500 h under continuous one-sun illumination.

关键词： charge transfer indium oxide interfacial layer perovskite solar cells

Sputtering under Mild Heating Enables High-Quality ITO for Efficient Semi-Transparent Perovskite Solar Cells

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Journal of Renewable Materials 2022年第10期10卷 2509-2518页

作者： Yongbin Jin Zheng Fang Liu Yang Kaikai Liu Mingliang Li Yaping Zhao Yujie Luo Huiping Feng Bingru Deng Chengbo Tian Changcai Cui liqiang xie Xipeng Xu Zhanhua Wei Xiamen Key Laboratory of Optoelectronic Materials and Advanced Manufacturing Institute of Luminescent Materials and Information DisplaysCollege of Materials Science and EngineeringHuaqiao UniversityXiamen361021China MOE Engineering Research Center for Brittle Materials Machining Huaqiao UniversityXiamen361021China

Semi-transparent perovskite solar cells(ST-PSCs)are promising in building-integrated photovoltaics(BIPVs)and tandem solar cells(TSCs).One of the keys to fabricate high-performance ST-PSCs is depositing efficient transparent *** tin oxide(ITO)is an excellent transparent conductive oxide with good light transmittance and high ***,the high sheet resistance of ITO sputtered at room temperature leads to the low fill factor(FF)and poor power conversion efficiency(PCE)of the ***,we study the effect of the sputtering temperature on the properties of ITO and the performance of *** find that when the sputtering temperature increases from the room temperature to 70℃,the crystallinity of the sputtered ITO gradually ***,the sheet resistance decreases and the corresponding device performance ***,once the sputtering temperature further increases over 70℃,the underlying hole transport layer will be damaged,leading to poor device ***,the optimized mild heating temperature of 70℃is applied and we obtain ST-PSCs with a champion PCE of 15.21%.We believe this mild heating assisted sputtering method is applicable in fabricating BIPVs and TSCs.

关键词： Indium tin oxide sputtering temperatures semi-transparent perovskite solar cells

Efficient Semi‑Transparent Wide‑Bandgap Perovskite Solar Cells Enabled by Pure‑Chloride 2D‑Perovskite Passivation

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Nano-Micro Letters 2023年第8期15卷 35-48页

作者： Liu Yang Yongbin Jin Zheng Fang Jinyan Zhang Ziang Nan Lingfang Zheng Huihu Zhuang Qinghua Zeng Kaikai Liu Bingru Deng Huiping Feng Yujie Luo Chengbo Tian Changcai Cui liqiang xie Xipeng Xu Zhanhua Wei Xiamen Key Laboratory of Optoelectronic Materials and Advanced Manufacturing Institute of Luminescent Materials and Information DisplaysCollege of Materials Science and EngineeringHuaqiao UniversityXiamen 361021People’s Republic of China MOE Engineering Research Center for Brittle Materials Machining Institute of Manufacturing EngineeringCollege of Mechanical Engineering and AutomationHuaqiao UniversityXiamen 361021People’s Republic of China Gold Stone(Fujian)Energy Company Limited Quanzhou 362005People’s Republic of China Collaborative Innovation Center of Chemistry for Energy Materials Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005People’s Republic of China

Wide-bandgap(WBG)perovskite solar cells suffer from severe non-radiative recombination and exhibit relatively large opencircuit voltage(V_(OC))deficits,limiting their photovoltaic ***,we address these issues by in-situ forming a well-defined 2D perovskite(PMA)_(2)PbCl_(4)(phenmethylammonium is referred to as PMA)passivation layer on top of the WBG active *** 2D layer with highly pure dimensionality and halide components is realized by intentionally tailoring the side-chain substituent at the aryl ring of the post-treatment ***-principle calculation and single-crystal X-ray diffraction results reveal that weak intermolecular interactions between bulky PMA cations and relatively low cation-halide hydrogen bonding strength are crucial in forming the well-defined 2D ***(PMA)_(2)PbCl_(4)forms improved type-I energy level alignment with the WBG perovskite,reducing the electron recombination at the perovskite/hole-transport-layer *** this strategy in fabricating semi-transparent WBG perovskite solar cells(indium tin oxide as the back electrode),the V_(OC)deficits can be reduced to 0.49 V,comparable with the reported state-of-the-art WBG perovskite solar cells using metal ***,we obtain hysteresis-free 18.60%-efficient WBG perovskite solar cells with a high V_(OC)of 1.23 V.

关键词： Wide-bandgap perovskite solar cells Transparent back electrodes Defect passivation Bulky cations