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Spatial variability of leaf wetness under different soil water conditions in rainfed jujube (Ziziphus jujuba Mill.) in the loess hilly region, China

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Journal of Arid Land 2022年第1期14卷 70-81页

作者： gao zhiyong WANG Xing State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China Xi'an University of TechnologyXi'an 710048China School of Agriculture Ningxia UniversityYinchuan 750021China

Leaf wetness provides a wide range of benefits not only to leaves,but also to ecosystems and *** regulates canopy eco-hydrological processes and drives spatial differences in hydrological *** spite of these functions,little remains known about the spatial distribution of leaf wetness under different soil water *** wetness measurements at the top(180 cm),middle(135 cm),and bottom(85 cm)of the canopy positions of rainfed jujube(Ziziphus jujuba Mill.)in the Chinese loess hilly region were obtained along with meteorological and soil water conditions during the growing seasons in 2019 and *** soil water non-deficit condition,the frequency of occurrence of leaf wetness was 5.45%higher at the top than at the middle and bottom of the canopy *** frequency of occurrence of leaf wetness at the top,middle and bottom of the canopy positions was over 80%at 17:00‒18:00(LST).However,the occurrence of leaf wetness at the top was earlier than those at the middle and bottom of the canopy ***,leaf drying at the top was also latter than those at the middle and bottom of the canopy *** wetness duration at the middle was similar to that at the bottom of the canopy position,but about 1.46-3.01 h less than that at the *** soil water deficit condition,the frequency of occurrence of leaf wetness(4.92%-45.45%)followed the order of top>middle>bottom of the canopy *** the onset of leaf wetness was delayed,the onset of wet leaf drying was advanced and the leaf wetness duration was *** wetness duration at the top was linearly related(R^(2)>0.70)to those at the middle and bottom of the canopy positions under different soil water *** conclusion,the hydrological processes at canopy surfaces of rainfed jujube depended on the position of leaves,thus adjusting canopy structure to redistribute hydrological process is a way to meet the water need of jujube.

关键词： canopy position leaf wetness rainfed jujube soil water condition loess hilly region

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Complex network theory-based condition recognition of electromechanical system in process industry

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Science China(Technological Sciences) 2016年第4期59卷 604-617页

作者： WANG RongXi gao JianMin gao zhiyong gao Xu JIANG HongQuan State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University

In order to recognize the different operating conditions of a distributed and complex electromechanical system in the process industry,this work proposed a novel method of condition recognition by combining complex network theory with phase space ***,a condition-space with complete information was reconstructed based on phase space reconstruction,and each condition in the space was transformed into a node of a complex ***,the limited penetrable visibility graph method was applied to establish an undirected and un-weighted complex network for the reconstructed ***,the statistical properties of this network were calculated to recognize the different operating conditions.A case study of a real chemical plant was conducted to illustrate the analysis and application processes of the proposed *** results showed that the method could effectively recognize the different conditions of electromechanical systems.A complex electromechanical system can be studied from the systematic and cyber perspectives,and the relationship between the network structure property and the system condition can also be analyzed by utilizing the proposed method.

关键词： complex network condition recognition phase space reconstruction complex electromechanical system

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An artificial immune and incremental learning inspired novel framework for performance pattern identification of complex electromechanical systems

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Science China(Technological Sciences) 2020年第1期63卷 1-13页

作者： WANG RongXi gao Xu gao JianMin gao zhiyong CHEN Kun PENG CaiYuan State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong UniversityXi'an 710049China Xi'an Thermal Power Research Institute Co. Ltd.Xi'an 710054China

Performance pattern identification is the key basis for fault detection and condition prediction,which plays a major role in ensuring safety and reliability in complex electromechanical systems(CESs).However,there are a few problems related to the automatic and adaptive updating of an identification *** to solve the problem of identification model updating,a novel framework for performance pattern identification of the CESs based on the artificial immune systems and incremental learning is proposed in this paper to classify real-time monitoring data into different performance ***,an unsupervised clustering technique is used to construct an initial identification ***,the artificial immune and outlier detection algorithms are applied to identify abnormal data and determine the type of immune ***,incremental learning is employed to trace the dynamic changes of patterns,and operations such as pattern insertion,pattern removal,and pattern revision are designed to realize automatic and adaptive updates of an identification *** effectiveness of the proposed framework is demonstrated through experiments with the benchmark and actual pattern identification *** an unsupervised and self-adapting approach,the proposed framework inherits the preponderances of the conventional methods but overcomes some of their drawbacks because the retraining process is not required in perceiving the pattern ***,this method can be flexibly and efficiently used for performance pattern identification of the ***,the proposed method provides a foundation for fault detection and condition prediction,and can be used in other engineering applications.

关键词： performance pattern identification complex electromechanical systems artificial immune incremental learning data classification

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Application research of multivariate linkage fluctuation analysis on condition evaluation in process industry

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Science China(Technological Sciences) 2018年第3期61卷 397-407页

作者： XIE JunTai gao JianMin gao zhiyong WANG RongXi WANG Zhen State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University

Abnormal conditions are hazardous in complex process systems, and the aim of condition recognition is to detect abnormal conditions and thus avoid severe accidents. The relationship of linkage fluctuation between monitoring variables can characterize the operation state of the system. In this study,we present a straightforward and fast computational method, the multivariable linkage coarse graining(MLCG) algorithm, which converts the linkage fluctuation relationship of multivariate time series into a directed and weighted complex network. The directed and weighted complex network thus constructed inherits several properties of the series in its structure. Thereby, periodic series convert into regular networks, and random series convert into random networks. Moreover, chaotic time series convert into scale-free networks. It demonstrates that the MLCG algorithm permits us to distinguish, identify, and describe in detail various time series. Finally, we apply the MLCG algorithm to practical observations series, the monitoring time series from a compressor unit, and identify its dynamic characteristics. Empirical results demonstrate that the MLCG algorithm is suitable for analyzing the multivariable linkage fluctuation relationship in complex electromechanical system. This method can be used to detect specific or abnormal operation condition, which is relevant to condition identification and information quality control of complex electromechanical system in the process industry.

关键词： complex electromechanical system linkage fluctuation modeling and analysis network structure entropy operation quality evaluation

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Coupling analysis-based false monitoring information identification of production system in process industry

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Science China(Technological Sciences) 2017年第6期60卷 807-817页

作者： gao zhiyong WANG RongXi JIANG HongQuan gao JianMin DONG RongGuang State Key Laboratory for Manufacturing Systems Engineering Xi 'an Jiaotong University Xi 'an 710049 China

False monitoring information is a major problem in process production system and several ineffective methods have been proposed to identify false monitoring information in the production system. In this paper, a new method is proposed to identify false monitoring information based on system coupling analysis and collision detection from the perspective of data analysis. Coupling multifractal features are extracted to reflect the changes in coupling relationship by utilizing the multifractal detrended cross-correlation analysis (MF-DXA). Each monitoring variable in process production system has more than one coupled variable, which can be regarded as multi-source. To achieve low redundancy in features and uniform description of coupling relationship, the feature level information fusion is studied based on modified Mahalanobis Taguchi system (MTS). False alarms are identified when the coupling relationships among the coupled monitoring variables collide. Analysis results of coupled R?ssler and Henon datasets indicate the feasibility of this method for selecting the effective coupling feature and uniform description of coupling relationship. The compressor system case of Coal Chemical Ltd. Group is studied and false monitoring information is identified.

关键词： false monitoring information coupling analysis MF-DXA MTS process industry

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Gas leakage recognition for CO2 geological sequestration based on the time series neural network

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Chinese Journal of Chemical Engineering 2020年第9期28卷 2343-2357页

作者： Denglong Ma Jianmin gao zhiyong gao Hongquan Jiang Zaoxiao Zhang Juntai Xie School of Mechanical Engineering Xi'an Jiaotong UniversityXi'an 710049China School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'an 710049China

The leakage of stored and transported CO2 is a risk for geological sequestration technology. One of the most challenging problems is to recognize and determine CO2 leakage signal in the complex atmosphere background. In this work, a time series model was proposed to forecast the atmospheric CO2 variation and the approximation error of the model was utilized to recognize the leakage. First, the fitting neural network trained with recently past CO2 data was applied to predict the daily atmospheric CO2. Further, the recurrent nonlinear autoregressive with exogenous input(NARX) model was adopted to get more accurate prediction. Compared with fitting neural network, the approximation errors of NARX have a clearer baseline, and the abnormal leakage signal can be seized more easily even in small release cases. Hence, the fitting approximation of time series prediction model is a potential excellent method to capture atmospheric abnormal signal for CO2 storage and transportation technologies.

关键词： Leakage identification Process safety Gas leakage Monitoring carbon sequestration CO2 storage

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Mechanism of calcium lignosulfonate in apatite and dolomite flotation system

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International Journal of Minerals,Metallurgy and Materials 2022年第9期29卷 1697-1704页

作者： Bo Feng Liangzhu Zhang Wenpu Zhang Huihui Wang zhiyong gao Jiangxi Key Laboratory of Mining Engineering Jiangxi University of Science and TechnologyGanzhou 341000China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China State Key Laboratory of Rare Metals Separation and Comprehensive Utilization Guangzhou 510600China

Since the physical and chemical properties of apatite and dolomite can be similar,the separation of these two minerals is ***,when performing this separation using the flotation method,it is necessary to search for selective *** experimental research was performed on the separation behavior of apatite and dolomite using calcium lignosulfonate as a depressant,and the mechanism by which this occurs was *** results show that calcium lignosulfonate has a depressant effect on both apatite and dolomite,but the depressant effect on dolomite is stronger at the same *** analysis shows that the adsorptive capacity of calcium lignosulfonate on dolomite is higher than that of apatite,which is due to the strong reaction between calcium lignosulfonate and the Ca sites on *** addition,there is a hydrogen bond between calcium lignosulfonate and dolomite,which further prevents the adsorption of sodium oleate to dolomite,thus greatly inhibiting the flotation of dolomite.

关键词： apatite dolomite calcium lignosulfonate depression mechanism

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Microstructure evolution and superelasticity behavior of Ti-Ni-Hf shape memory alloy composite with multi-scale and heterogeneous reinforcements

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Journal of Materials Science & Technology 2020年第7期42卷 113-121页

作者： Xiaoyang Yi Bin Sun Weihong gao Xianglong Meng zhiyong gao Wei Cai Liancheng Zhao School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

In the present study,the in-situ TiB whisker was introduced into the Ti-Ni-Hf shape memory alloy composite by the in-situ reaction of the Ti-Ni-Hf alloy powder and TiB2 ***(Ti,Hf)2 Ni phase also precipitated,accompanied with the formation of TiB ***,the residual TiB2 particles can be observed,as the TiB2 content was higher than 0.7 wt%.Thereinto,the larger scale reinforcements constituted the quasi-continuous network *** smaller scale reinforcements distributed in the interior of the network *** two-scale reinforcements showed the uniform distribution at macroscopic level and inhomogeneous distribution at microscopic *** single stage B19?B2 martensitic transformation occurred in the Ti-Ni-Hf *** addition,the martensitic transformation temperatures continuously decreased with the increased TiB2 content owing to the compositional and mechanical *** moderate TiB2 addition not noly enhanced the matrix strength,but also significantly improved the *** excellent superelaticity with the completely recoverable strain of 4%can be obtained in the Ti-Ni-Hf composite containing 0.7 wt%TiB2.

关键词： Ti-Ni-Hf composite Shape memory alloy Microstructure Martensitic transformation High temperature superelasticity

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Ethylenediamine tetramethylenephosphonic acid as a selective collector for the improved separation of chalcopyrite against pyrite at low alkalinity

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International Journal of Mining Science and Technology 2023年第7期33卷 873-882页

作者： Jianjun Wang gaogui Jing Renji Zheng Zijie Huang Wei Sun zhiyong gao School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China Hunan International Joint Research Centre for Efficient and Clean Utilization of Critical Metal Mineral Resources Central South UniversityChangsha 410083China

Chalcopyrite is the main Cu-containing mineral and cannot be separated well from pyrite using traditional xanthate collectors with large amounts of lime depressant, resulting in difficulties of the tailing treatment and associated precious metals recovery. Therefore, in this study, the green and odourless ethylenediamine tetramethylenephosphonic acid(EDTMPA) was introduced as a novel chalcopyrite collector. Flotation results from the binary mineral mixture and real ore demonstrated that EDTMPA could realize the selective separation of chalcopyrite from pyrite relative to ethyl xanthate(EX) without any depressants within the wide p H range of 6.0–11.0, and might replace the traditional high-alkaline lime process. Electrochemical and Fourier transform infrared spectra measurements indicated that the difference in adsorption performance of EDTMPA on chalcopyrite and pyrite was larger than that of EX, suggesting a better selectivity for EDTMPA. Density functional theory calculations demonstrated that there were stronger chemical bonds between P—O groups of EDTMPA and the Fe/Cu atoms on chalcopyrite in the form of a stable six-membered ring. Crystal chemistry calculations further revealed that the activity of metal atoms of chalcopyrite was higher than that of pyrite. Therefore, these basic theoretical results and practical application provide a guidance for the industrial application of EDTMPA in chalcopyrite flotation.

关键词： Chalcopyrite Pyrite Flotation Ethylenediamine tetramethylenephosphonic acid Collector

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Relations between spatial distribution and sequence types of the Cambrian-Ordovician marine source rocks in Tarim Basin

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Chinese Science Bulletin 2007年第A1期52卷 92-102页

作者： gao zhiyong ZHANG ShuiChang ZHANG XingYang ZHU RuKai Experiment & Research Center of Petroleum Geology Research Institute of Petroleum Exploration and Development PetroChina Beijing100083 China

Marine source rocks are considered to be mainly composed of the Cambrian-Ordovician deposit in Tarim Basin. Based on the previous studies made by other researchers, the authors calculated the thickness and distribution scale of these Cambrian-Ordovician source rocks by integrating sequence stratigraphy with investigations on sedimentary environments, well-shooting demarcating and calibrating the thickness of unknown source rocks with the thickness of the known ones according to characteristics of the source rocks that have "double track" seismic lineup reflectance. The results showed that the distribution area of the Lower-Cambrian Yuertusi Fm. source rock in platform inner depressions, slopes and deep basins is much bigger than that of the Middle Cambrian evaporite-lagoon source rock. Moreover, the former is superior to the latter in terms of the source rock quality. Likewise, the Middle-Ordovician Heituao Fm. source rock in the slopes and deep basins has a much wider distribution and better quality than the Upper Ordovician, and its quality is also better than those of the Shaergan and Yinggan Fms. source rock within platforms as well as the lime-mud-mound source rock along the fringe of the Upper-Ordovician platform. Most good Lower-Cambrian source rocks of the Kalpin outcrop lie on the initial ingression surface or in the condensed member of the Type I sequence. In this section, the source rock in Type II is inferior to that in Type I, even being far from an effective one (TOC: <0.5%). Likewise, the good Middle-Ordovician Heituao source rock also lies on the initial ingression surface or in the condensed member of the Type I sequence, while the poor Yinggan source rock and the lime-mud-mound along the fringe of the platform develop all in the Type II sequence. Under the condition of the same sea-level rising altitude and time, the ingression displacement (S1) at the base border in Type I is larger than S2 in Type II. Thus, the distribution of the source rock dev

关键词：寒武纪-奥陶纪体系原岩石海洋序列

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