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Preparation and Characterization of LiTaO_3 Films Derived by an Improved Sol-Gel Process

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Acta Metallurgica Sinica(English Letters) 2013年第3期26卷 299-302页

作者： Jun GOU Jun WANG Ming YANG zehua huang Weizhi LI Yadong JIANG State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Information University of Electronic Science and Technology of China

In this paper, an improved sol-gel method was suggested to obtain high-concentration LiTaO3 precursor solution for simplified experimental conditions and thicker films, by mixing lithium acetate and tantalum ethoxide in a 1, 2-Propylene glycol solution. Compared to traditional methods, the process was done without weak acidic solution and absolute dry experimental condition. Results of a comparative study of LiTaO3 thin films derived by the improved sol-gel process and a traditional process using 2-methoxy ethanol as solvent were presented. Nano-crystalline LiTaO3 films with rhombohedral structures were formed in both methods after annealing at 650℃ for 5 min. The thickness of each LiTaO3 layer coated onto the substrate increased from 25 nm to 110 nm when 2-methoxy ethanol was replaced by 1, 2-Propylene glycol. LiTaO3 films with a stronger preferential orientation were obtained in 1, 2-Propylene glycol due to its higher boiling point and slower volatilization rate. On the other hand, the diffraction peak intensity of LiTaO3 thin films prepared using 1, 2-Propylene glycol was weaker than that of the films prepared using 2-methoxy ethanol due to decreased times of annealing.

关键词： LiTaO3 Thin film Sol-gel Crystallization

Mn/ZIF-90对水中重金属离子的吸附性能研究

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应用化工 2025年第1期54卷 137-142,146页

作者：韩臻谭文渊黄泽华陈建书刘佳明刘鑫叶江自贡乡村振兴发展服务中心四川自贡643000 四川轻化工大学化学与工程学院四川自贡643000 北京清新环境技术股份有限公司北京100083

以乙酸锰、乙酸锌、咪唑-2-甲醛等原料合成锰掺杂的改性金属骨架结构材料Mn/ZIF-90,将该材料应用于Cu、Pb、Cd、Cr、Ni和As离子的吸附,通过调控水的pH值测试Mn/ZIF-90的吸附性能,并以Cu、Cd和Cr元素为例,对材料的吸附结果进行拟合,探讨... 详细信息

以乙酸锰、乙酸锌、咪唑-2-甲醛等原料合成锰掺杂的改性金属骨架结构材料Mn/ZIF-90,将该材料应用于Cu、Pb、Cd、Cr、Ni和As离子的吸附,通过调控水的pH值测试Mn/ZIF-90的吸附性能,并以Cu、Cd和Cr元素为例,对材料的吸附结果进行拟合,探讨材料的吸附机理。结果表明,20 mg改性后的Mn/ZIF-90材料对pH为6.5~8.0、离子浓度为0.02 mg/L的50 mL农业用水中的上述6种离子可做到10 min内吸附率100%的完全去除,同时不存在Mn元素泄露的现象。经Langmuir、Freundlich、Temkin、D-R(Dubinin-Radushkevich)和Scatchard模型拟合可知,材料对各离子的吸附主要以物理吸附为主,同时存在化学吸附。

关键词：吸附农业用水金属骨架结构材料 ZIF材料

Water quality soft-sensor prediction in anaerobic process using deep neural network optimized by Tree-structured Parzen Estimator

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Frontiers of Environmental Science & Engineering 2023年第6期17卷 23-35页

作者： Junlang Li Zhenguo Chen Xiaoyong Li Xiaohui Yi Yingzhong Zhao Xinzhong He zehua huang Mohamed A.Hassaan Ahmed El Nemr Mingzhi huang SCNU Environmental Research Institute Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of EnvironmentSchool of EnvironmentSouth China Normal UniversityGuangzhou 510006China Fujian Environmental Protection Design Institute Co.Ltd Fuzhou 350000China National Institute of Oceanography and Fisheries NIOFAlexandria 21556Egypt SCNU Qingyuan Institute of Science and Technology Innovation Co. Ltd.Qingyuan 511517China

Anaerobic process is regarded as a green and sustainable process due to low carbon emission and minimal energy consumption in wastewater treatment plants(WWTPs).However,some water quality metrics are not measurable in real time,thus influencing the judgment of the operators and may increase energy consumption and carbon *** of the solutions is using a soft-sensor prediction *** article introduces a water quality soft-sensor prediction method based on Bidirectional Gated Recurrent Unit(BiGRU)combined with Gaussian Progress Regression(GPR)optimized by Tree-structured Parzen Estimator(TPE).TPE automatically optimizes the hyperparameters of BiGRU,and BiGRU is trained to obtain the point prediction with GPR for the interval ***,a case study applying this prediction method for an actual anaerobic process(2500 m^(3)/d)is carried *** show that TPE effectively optimizes the hyperparameters of *** point prediction of CODeff and biogas yield,R^(2)values of BiGRU,which are 0.973 and 0.939,respectively,are increased by 1.03%–7.61%and 1.28%–10.33%,compared with those of other models,and the valid prediction interval can be ***,the proposed model is assessed as a reliable model for anaerobic process through the probability prediction and reliable *** is expected to provide high accuracy and reliable water quality prediction to offer basis for operators in WWTPs to control the reactor and minimize carbon emission and energy consumption.

关键词： Water quality prediction Soft-sensor Anaerobic process Tree-structured Parzen Estimator

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Assessing Landsat-8 and Sentinel-2 spectral-temporal features for mapping tree species of northern plantation forests in Heilongjiang Province,China

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Forest Ecosystems 2022年第3期9卷 344-356页

作者： Mengyu Wang Yi Zheng Chengquan huang Ran Meng Yong Pang Wen Jia Jie Zhou zehua huang Linchuan Fang Feng Zhao Key Laboratory of Geographical Process Analysis&Simulation of Hubei Province/College of Urban and Environmental Sciences Central China Normal UniversityWuhan430079China Department of Geographical Sciences University of MarylandCollege ParkMD20742USA Macro Agriculture Research Institute Interdisciplinary Sciences Research InstituteCollege of Resources and EnvironmentHuazhong Agricultural UniversityWuhan430070China Institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing100091China Key Laboratory of Forestry Remote Sensing and Information System National Forestry and Grassland AdministrationBeijing100091China

Background:Accurate mapping of tree species is highly desired in the management and research of plantation forests,whose ecosystem services are currently under ***-series multispectral satellite images,e.g.,from Landsat-8(L8)and Sentinel-2(S2),have been proven useful in mapping general forest types,yet we do not know quantitatively how their spectral features(e.g.,red-edge)and temporal frequency of data acquisitions(e.g.,16-day vs.5-day)contribute to plantation forest mapping to the species ***,it is unclear to what extent the fusion of L8 and S2 will result in improvements in tree species mapping of northern plantation forests in ***:We designed three sets of classification experiments(i.e.,single-date,multi-date,and spectral-temporal)to evaluate the performances of L8 and S2 data for mapping keystone timber tree species in northern *** first used seven pairs of L8 and S2 images to evaluate the performances of L8 and S2 key spectral features for separating these tree species across key growing *** we extracted the spectral-temporal features from all available images of different temporal frequency of data acquisition(i.e.,L8 time series,S2 time series,and fusion of L8 and S2)to assess the contribution of image temporal frequency on the accuracy of tree species mapping in the study ***:1)S2 outperformed L8 images in all classification experiments,with or without the red edge bands(0.4%–3.4%and 0.2%–4.4%higher for overall accuracy and macro-F1,respectively);2)NDTI(the ratio of SWIR1 minus SWIR2 to SWIR1 plus SWIR2)and Tasseled Cap coefficients were most important features in all the classifications,and for time-series experiments,the spectral-temporal features of red band-related vegetation indices were most useful;3)increasing the temporal frequency of data acquisition can improve overall accuracy of tree species mapping for up to 3.2%(from 90.1%using single-date imagery to 93.3%using S2 time-series),yet similar ov

关键词： Tree species mapping Plantation forests Red-edge features Temporal frequency of data acquisition Fusion of Landsat-8 and Sentinel-2

Improved Yield Prediction of Ratoon Rice Using Unmanned Aerial Vehicle-Based Multi-Temporal Feature Method

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Rice science 2023年第3期30卷 247-256,I0039-I0042页

作者： ZHOU Longfei MENG Ran YU Xing LIAO Yigui huang zehua LÜZhengang XU Binyuan YANG Guodong PENG Shaobing XU Le College of Resources and Environment Huazhong Agricultural UniversityWuhan 430070China National Key Laboratory of Crop Genetic Improvement/Hubei Hongshan Laboratory/Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River Ministry of Agriculture and Rural Affairs/College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China College of Agriculture Northeast Agricultural UniversityHarbin 150006China Harbin Institute of Technology Institute for Artificial Intelligence Co. LtdHarbin 150000China

Pre-harvest yield prediction of ratoon rice is critical for guiding crop interventions in precision ***,the unique agronomic practice(i.e.,varied stubble height treatment)in rice ratooning could lead to inconsistent rice phenology,which had a significant impact on yield prediction of ratoon ***-temporal unmanned aerial vehicle(UAV)-based remote sensing can likely monitor ratoon rice productivity and reflect maximum yield potential across growing seasons for improving the yield prediction compared with previous ***,in this study,we explored the performance of combination of agronomic practice information(API)and single-phase,multi-spectral features[vegetation indices(VIs)and texture(Tex)features]in predicting ratoon rice yield,and developed a new UAV-based method to retrieve yield formation process by using multi-temporal features which were effective in improving yield forecasting accuracy of ratoon *** results showed that the integrated use of VIs,Tex and API(VIs&Tex+API)improved the accuracy of yield prediction than single-phase UAV imagery-based feature,with the panicle initiation stage being the best period for yield prediction(R^(2) as 0.732,RMSE as 0.406,RRMSE as 0.101).More importantly,compared with previous multi-temporal UAV-based methods,our proposed multi-temporal method(multi-temporal model VIs&Tex:R^(2) as 0.795,RMSE as 0.298,RRMSE as 0.072)can increase R^(2) by 0.020-0.111 and decrease RMSE by 0.020-0.080 in crop yield *** study provides an effective method for accurate pre-harvest yield prediction of ratoon rice in precision agriculture,which is of great significance to take timely means for ensuring ratoon rice production and food security.

关键词： ratoon rice yield prediction unmanned aerial vehicle multi-temporal feature agronomic practice stubble height

The Research of Indoor Three-Dimensional Positioning Algorithm Based on Ultra-Wideband Technology

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The Research of Indoor Three-Dimensional Positioning Algorit...

中国企业相机治理结构的一项考察——对490家上市公司“两职”设置问题的实证分析

第三十九届中国控制会议

作者： Xin Wang zehua huang FuQuan Zheng Xincheng Tian School of Control Science and Engineering Shandong University Institute of Automation of Shandong Academy of Sciences

In the positioning of the target in the three-dimensional indoor scene, the non-line of sight(NLOS) error caused by the occlusion of the obstacle will seriously reduce the positioning accuracy of Chan algorithm. The Taylor series positioning algorithm can suppress the NLOS error, but the algorithm is dependent on the selection of the initial value, and the initial value selection is not suitable, which can lead to the non-convergence of the algorithm. Aiming at the above problems, a fast and accurate Chan-Taylor series joint three-dimensional localization algorithm is proposed. First, the time of arrival(TOA) data obtained by the ultra-wideband(UWB) technology measurement is analyzed by the residual discrimination method, and whether the NLOS error exists in the measured data is identified. Then, aiming at the existence of NLOS error, the positioning result obtained by the Chan algorithm is used as the initial positioning value of the Taylor series positioning algorithm, and the positioning position is further iteratively calculated by the Taylor series expansion method. In the case of the line of sight distance(LOS), a single Chan location algorithm is still used for calculation. The experimental results show that the Chan-Taylor series joint three-dimensional localization algorithm improves the positioning speed and effectively suppresses the adverse effect of NLOS error on the positioning accuracy, and can reach the positioning accuracy of less than 0.2 m in 73% case.

关键词： Three-dimensional positioning NLOS Chan algorithm Taylor series expansion algorithm

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学术研究 2001年第2期 31-37页

作者：李子江黄泽华广东工业大学经济管理学院教授广东广州510090 佛山市禅科发展有限公司广东佛山528000

股东会、董事会、总经理和监事会构成了现代公司治理结构的基本内容 ,其中董事长与总经理两职的关系是普遍受到关注的问题。本文对董事长与总经理两职是否分任进行研究 ,通过对 4 90家中国上市公司的股权结构、董事会规模、监事会规模... 详细信息

股东会、董事会、总经理和监事会构成了现代公司治理结构的基本内容 ,其中董事长与总经理两职的关系是普遍受到关注的问题。本文对董事长与总经理两职是否分任进行研究 ,通过对 4 90家中国上市公司的股权结构、董事会规模、监事会规模、资本构成、公司绩效五方面进行统计分析 ,试图回答中国上市公司中董事长与总经理两职分离问题 ,从此探讨中国股份制公司发展的一些规律性问题。

关键词：股权结构治理结构公司绩效制衡

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肠道菌群对黏蛋白2的影响及其作用机制

胃肠病学 2019年第2期24卷 111-114页

作者：黄则华曾悦黄春兰上海交通大学附属第一人民医院消化科 201620

黏蛋白2(MUC2)是由肠道杯状细胞分泌的一种高度糖基化的分泌型黏蛋白,是组成肠黏液屏障的主要成分,在防御致病微生物入侵以及协助肠道益生菌定植等方面均具有重要作用。肠道菌群参与调控人体的诸多生理功能,可通过不同机制调控MUC2的合... 详细信息

黏蛋白2(MUC2)是由肠道杯状细胞分泌的一种高度糖基化的分泌型黏蛋白,是组成肠黏液屏障的主要成分,在防御致病微生物入侵以及协助肠道益生菌定植等方面均具有重要作用。肠道菌群参与调控人体的诸多生理功能,可通过不同机制调控MUC2的合成、分泌以及降解,从而影响MUC2的质和量。本文就肠道菌群对MUC2的影响及其作用机制作一综述。

关键词：黏蛋白2 肠道菌群肠道屏障 NF-κB NLRP6

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微型斯特林制冷机高温适应性实验研究

低温与超导 2024年第4期52卷 58-63页

作者：黄泽华黄太和曾勇孙建黄立武汉高德红外股份有限公司武汉430205

随着高工作温度HOT(High Operation Temperature)红外探测器的应用愈加广泛,更多应用场景要求微型斯特林制冷机在70℃以上的高温环境运行,这对制冷机高温适应性提出了挑战。基于研究气动型斯特林制冷机的高温适应性,通过高温环境对阻抗... 详细信息

随着高工作温度HOT(High Operation Temperature)红外探测器的应用愈加广泛,更多应用场景要求微型斯特林制冷机在70℃以上的高温环境运行,这对制冷机高温适应性提出了挑战。基于研究气动型斯特林制冷机的高温适应性,通过高温环境对阻抗和回热器损失的变化规律进行分析,研究高温环境对充气压力及谐振频率的影响,以及回热器丝网参数与高温适应性的关系,得出高温环境对制冷效率造成性能衰减的影响因素。实验表明:环境温度升高使得气体压力升高,使谐振频率提升。适当减少孔隙率可以减少回热器在高温环境的流阻损失,提高制冷效率。本文的研究对提高斯特林制冷机的热环境适应性具有一定的参考价值。

关键词：斯特林制冷机高温适应性损失实验研究