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Changjiang River sediment delivering into the sea in response to water storage of Sanxia Reservoir in 2003

Acta Oceanologica Sinica 2006年第2期25卷 71-79页

作者： CHU zhongxin ZHAI Shikui CHEN Xiufa College of Marine Geosciences Ocean University of China Qingdao 266003 China Development and Research center China Geological Survey Beijing 100083 China

The Sanxia Reservoir on the Changjiang River stored water from 1 to 10 June and from 25 October to 5 November in 2003, elevating the water level to 135 and 139 m above mean sea level at the dam, respectively. A monthly dataset of water discharge, suspended sediment concentration （SSC） and sediment load of the Changjiang River from 1953 to 2003 measured at the Datong Hydrological Gauging Station of the downstreammost Changjiang River was mainly used to examine the Changjiang River sediment delivering into the sea in 2003 in response to the Sanxia Reservoir water storages in the same year. The results show that （1） compared with those in 2002, 2001, and the multi-yearly （1953-2000） average, both annual SSC and sediment load at Datong in 2003 were markedly reduced, and they were even smaller than the multi-yearly （1953-2000） minimum, although the annual runoff in 2003 did not change largely; and （2） compared with those in the corresponding months in 2002, 2001 and the multi-monthly average from 1953 to 2000, monthly SSC and sediment load at Datong both in June and November of 2003 were also markedly reduced, and those in June 2003 were even smaller than the multi-monthly minimum from 1953 to 2000. These may indicate that sediment sedimentation in the Sanxia Reservoir resulting from the Sanxia Reservoir water storage should be the main cause of the decreased annual and monthly SSC and sediment load of the Changjiang River into the sea in 2003. Besides, it seems that the Sanxia Reservoir water storage in the early June （flood season） of 2003 had more impacts on the decreased monthly SSC into the sea than that in the late October and early November （approximately non-flood season） of 2003.

关键词： Changjiang (Yangtze) River Sanxia Reservoir water storage sediment

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Transformation mechanism of nutrient elements in the process of biochar preparation for returning biochar to soil

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Chinese Journal of Chemical Engineering 2017年第4期25卷 477-486页

作者： Shuangshuang Tian zhongxin Tan Alfreda Kasiuliene Ping Ai College of Resources and Environment HuazhongAgricultural UniversityWuhan 430070China Waste Science and Technology Department of CivilEnvironmental and Natural Resources EngineeringLulea University of TechnologySE-97187 LuleaSweden College of Engineering Huazhong Agricultural UniversityWuhan 430070China

Returning biochar to soil is a heavily researched topic because biochar functions well for soil improvement. There is a significant loss of nutrients, which occurs during biochar preparation before biochar is returned to soil,thereby seriously undermining biochar＇s efficacy. Therefore, the transformation mechanisms of biochar p H,mass, nutrients and metals during pyrolysis under different atmospheres and temperatures were studied such that the best method for biochar preparation could be developed. Several conclusions can be reached：（1） a CO2 atmosphere is better than a N2 atmosphere for biochar preparation, although preparation in a CO2 atmosphere is not a common practice for biochar producers;（2） 350 ℃is the best temperature for biochar preparation because the amount of nutrient loss is notably low based on the premise of straw transferred into biochar; and（3） transforming mechanisms of pH, N, P and K are also involved in the biochar preparation process.

关键词： nutrient Transformation pyrolysis seriously alkaline premise kinetics notably thereby volatile

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黑麦挂面微波间歇干燥特性及动力学模型研究

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食品与发酵工业 2025年第05期51卷 241-247页

作者：程丽丽张媛媛唐雪燕王娇张仲欣漯河食品工程职业大学食品与生物工程学院河南科技大学食品与生物工程学院

以黑麦挂面为对象，采用微波间歇干燥方法，研究不同微波功率、装载量和面条厚度对黑麦挂面干燥特性和有效水分扩散系数的影响，通过SPSS软件对5种干燥动力学模型进行拟合，得到黑麦挂面间歇微波干燥动力学模型，并对微波干燥黑麦挂面... 详细信息

以黑麦挂面为对象，采用微波间歇干燥方法，研究不同微波功率、装载量和面条厚度对黑麦挂面干燥特性和有效水分扩散系数的影响，通过SPSS软件对5种干燥动力学模型进行拟合，得到黑麦挂面间歇微波干燥动力学模型，并对微波干燥黑麦挂面进行品质评价。结果表明，黑麦挂面微波间歇干燥主要表现为降速干燥，微波功率越大、装载量越小、挂面厚度越薄，干燥速度越快，干燥用时越短；干燥中有效水分扩散系数为1.180 39×10-11～2.967 02×10-11m2/s,并随着微波功率和挂面厚度的增加而增大，随着装载量的增加而减小；通过模型拟合发现，Logarithmic模型是黑麦挂面间歇微波干燥的最佳模型，R2最大，χ2和均方根误差最小，可有效描述黑麦挂面微波干燥时水分的变化过程；微波干燥黑麦挂面色泽较好，黑红发亮，抗弯曲特性高，熟断条率为0,蒸煮损失率为7.70%,质构特性良好，具有商品价值。该研究为微波技术在挂面生产的应用提供理论依据。

关键词：黑麦挂面微波间歇干燥干燥特性动力学模型有效水分扩散系数

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Mean square consensus of uncertain discrete-time stochastic multi-agent systems with x-dependent noise

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Journal of Control and Decision 2020年第2期7卷 196-213页

作者： Shuang Liang zhongxin Liu Zengqiang Chen College of Artificial Intelligence Nankai UniversityTianjin 300353People’s Republic of China Tianjin Key Laboratory of Intelligent Robotics Nankai UniversityTianjin 300353People’s Republic of China

In this paper, the mean square consensus control problem is investigated for linear uncertain discrete-time multi-agent systems withx-dependent noise and time-varying delays. Under undirected connected topology, the robust consensus problem of multi-agent systems is converted into the robust stabilisation problem for thediscrete-time stochastic systems. By utilising Lyapunov functionaland the linear matrix inequality method, some new sufficient conditions are derived to guarantee the consensus of uncertain discretetime stochastic multi-agent systems. Based on the state feedbackcontroller protocol with time-varying delays, a new consensus criterion is established for the discrete-time stochastic multi-agent systems with parameter uncertainties. Finally, numerical examples areprovided to illustrate the effectiveness of the proposed results.

关键词： Discrete multi-agent systems mean square consensus parameter uncertainties time-varying delays linear matrix inequalities

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Modeling and reachability of probabilistic finite automata based on semi-tensor product of matrices

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Science China(Information Sciences) 2018年第12期61卷 202-204页

作者： Zhipeng ZHANG Zengqiang CHEN zhongxin LIU College of Computer and Control Engineering Nankai University Tianjin Key Laboratory of Intelligent Robotics Nankai University

Dear editor,As mathematical models, finite automata have been a powerful synthesis tool for modeling and analyzing discrete event systems where states and events are a finite logical or discrete set. In deterministic finite automata, the successor can be uniquely determined by the predecessor and input event. In other words, it exhibits a deterministic behavior. As a practical and theoretical motivation, probabilistic finite automata (PFAs)

关键词： Modeling and reachability of probabilistic finite automata based on semi-tensor product of matrices

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Bifunctional Fe-doped CoP@Ni_(2)P heteroarchitectures for highefficient water electrocatalysis

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Nano Research 2022年第10期15卷 8865-8871页

作者： zhongxin Duan Depeng Zhao Yuchen Sun Xiaojie Tan Xiang Wu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

It is important to develop economical and durable electrocatalysts for sustainable energy conversion ***,the current catalysts still suffer from insufficient hydrogen adsorption ***,we report a kind of novel bi-phosphide catalyst through constructing heterogeneous structures and cation *** obtained sample delivers an outstanding hydrogen evolution reaction(HER)performance at all pH *** oxygen evolution reaction(OER)electrocatalyst,Fe-CoP@Ni_(2)P samples show an overpotential of 237 mV at 50 mA·cm^(−2) in alkaline *** electrolysis of water,Fe-CoP@Ni_(2)P catalysts deliver a cell voltage of 1.59 V at 50 mA·cm^(−2) and long ***,density functional theory(DFT)calculation further confirms that the doped heterostructure promotes Gibbs free energy for hydrogen *** the significant increase in the density of total states(DOS)also enhances the catalytic activity of HER.

关键词： Fe doping phosphide heterostructure all pH range hydrogen evolution reaction(HER) electrolysis

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Microstructure and properties of as-cast Cu-Cr-Zr alloys with lanthanum addition

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Journal of Rare Earths 2018年第4期36卷 424-429页

作者： Jilin Li Lili Chang Shengli Li Xinde Zhu zhongxin an Department of Material Science and Engineering Shandong UniversityJinan 250061China Zhengzhou Yutong Bus Co.Ltd. Zhengzhou 450061China

Cu-0.45 Cr-0.2 Zr-xLa（x = 0-0.48） alloys were prepared by vacuum casting. The effects of La addition and orientation on the microstructure and properties of the as-cast alloy were investigated by an optical microscope, a scanning electron microscope with an energy dispersive X-ray spectrometer, a tensile testing machine and an electrical conductivity tester. The result shows that the addition of La significantly refines the columnar grainsize and decreases the secondary dendrite arm spacing. Trace addition of La improves the room temperature ultimate tensile strength,elongation and electrical conductivity mainly by purifying during melting and casting. The ultimate tensile strength, elongation and electrical conductivity significantly decrease with the increase of La content due to formation of coarse particles and oxides, which severely harm the performance of the Cu-0.45 Cr-0.2 Zr-xLa alloys. The Cu-0.45 Cr-0.2 Zr-0.13 La alloy possesses a good combination of room temperature ultimate tensile strength, elongation and electrical conductivity. In addition, room temperature ultimate tensile strength and electrical conductivity along transverse direction of the ingot are higher than that along longitudinal direction,which is mainly ascribed to different distribution of grain boundary and grain orientation.

关键词： La Cu-Cr-Zr alloy Orientation Ultimate tensile strength Electrical conductivity Rare earths

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Observer-based fault detection for switched systems with all unstable subsystems

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Journal of Control and Decision 2021年第2期8卷 116-123页

作者： Qingyu Su zhongxin Fan Jian Li School of Automation Engineering Northeast Electric Power University169 Changchun RoadChuanying DistrictJilin 132012People’s Republic of China

This paper deals with the fault detection observer design problem for switched system with all modes ***,the error system model is *** the consideration of the instability caused by the unobservable condition of(Ai,Ci),a switching signal is obtained via average dwell time method and discretised Lyapunov *** means of linear matrix inequalities,sufficient conditions pledging exponential stability and H∞performance are *** transferring the observer design problem into H∞performance analysis,proper observer gain is obtained via solving these *** the end,the validity of the proposed Luenberger observer is verified by an example.

关键词： Average dwell time discretised Lyapunov function weighted H∞performance Luenberger observer unstable subsystems

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左房室整体纵向应变对心力衰竭患者重组人脑脑钠肽治疗后左心功能早期变化的评价

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中国循证心血管医学杂志 2025年第1期17卷 88-93页

作者：赵建鹏赵忠信李真河北省衡水市第六人民医院药剂科衡水053200

目的探究左房室整体纵向应变(GLS)对心力衰竭(HF)患者重组人脑脑钠肽(rhBNP)治疗后左心功能早期变化的评价。方法选择2020年9月至2023年9月于河北省衡水市第六人民医心内科就诊的HF患者106例作为研究对象,根据治疗方式分为rhBNP治疗(观... 详细信息

目的探究左房室整体纵向应变(GLS)对心力衰竭(HF)患者重组人脑脑钠肽(rhBNP)治疗后左心功能早期变化的评价。方法选择2020年9月至2023年9月于河北省衡水市第六人民医心内科就诊的HF患者106例作为研究对象,根据治疗方式分为rhBNP治疗(观察组)和常规治疗(对照组),每组各53例。比较两组患者临床资料以及GLS和左心功能相关参数的情况。多元线性回归分析GLS值与左心功能参数的关系。多因素Logistic分析影响左心功能的独立影响因素。分层交互分析性别对GLS与左心功能之间关系的影响作用。采用限制性立方样条模型分析GLS值与rhBNP治疗后左心功能风险的剂量反应关系。分析各指标对左心功能不佳的预测能力,y=1-1/(1+e-z)回归方程建立预测模型,并使用十字交叉验证法对该模型进行验证。结果观察组患者的GLS、左心室轴向整体收缩期最大峰值应变(GCS)、心脏整体收缩期应变率(GSRs)水平均显著低于对照组(P0.05)。GLS与GCS、GSRs显著相关(P<0.001)。多因素Logistic分析显示性别(OR=6.254,95%CI:5.255~9.226,P=0.002)、左心室射血分数(LVEF,OR=2.148,95%CI:1.297~4.268,P=0.038)、GLS(OR=0.513,95%CI:0.486~0.864,P=0.019)、GCS(OR=0.642,95%CI:0.598~0.817,P=0.021)指标均是影响患者左心功能的独立影响因素。经过交互检验作用(P交互)后发现无论是否调整其他因素,性别均不能影响GLS与左心功能之间的关系。当GLS值≥0时,左心功能不佳风险几乎不再随GLS值增加而变化(HR=1.465,95%CI:1.244~1.743,P<0.001)。结构方程预测模型整体适配情况较好[内部验证前AUC=0.846(95%CI:0.831~0.876,P<0.05),内部验证后AUC=0.868(95%CI:0.827~0.881,P<0.05)],能很好地反映各影响因素与HF患者rhBNP治疗后左心功能的关系。预测模型较稳定(Nagelkerke R2=0.798)。结论GLS可以很好地评价HF患者rhBNP治疗后左心功能的早期变化,GLS值同左心功能指标的联合能够提高其对HF患者左心功能不佳风险的预测能力。

关键词：左房室整体纵向应变心力衰竭重组人脑脑钠肽左心功能早期变化

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Seasonal Variation of Environmental Variables and Phytoplankton Community Structure and Their Relationship in Liaodong Bay of Bohai Sea,China

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Journal of Ocean University of China 2018年第4期17卷 864-878页

作者： YANG Guojun WU zhongxin SONG Lun LU Xiaoqian College of Fisheries and Life Science Dalian Ocean UniversityDalian 116023China Center for Marine Ranching Engineering Science Research of Liaoning Province Dalian Ocean UniversityDalian 116023China College of Marine Science and Environment Dalian Ocean UniversityDalian 116023China Liaoning Ocean and Fisheries Science Research Institute Dalian 116023China

In this paper, systematic studies on the changes in concentrations of the environmental factors and the net-phytoplankton community, and the relationship between them in the Liaodong Bay, Bohai Sea during 2013 are presented. The PCA results showed that higher levels of nutrients and dissolved heavy metals in the river-estuary-bay system were closely related to the river runoff. Since the influences of industrial and anthropogenic activities, the Liaodong Bay coastal areas are facing a huge environmental challenge of nutrients and heavy metal pollution. Net-phytoplankton community structure showed obvious seasonal succession, among which the dominant and(or) key species were the main factors affecting community structure change and stability. Under certain environmental conditions, the dominant species and(or) key species dominated the phytoplankton community structure succession. The Bio-ENV results suggested that the seawater temperature, nutrient, Cu, Pb, Zn, and Cd in Liaodong Bay are important environmental variables that affect the phytoplankton community structure. Anthropogenic activities have significantly contributed to the changes in concentrations of environmental factors and the net-phytoplankton community structure and stability, and the relationship between them.

关键词： Liaodong Bay environmental variables eutrophication trace metals phytoplankton community ecological stability

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