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Discovering forest height changes based on spaceborne lidar data of ICESat-1 in 2005 and ICESat-2 in 2019:a case study in the Beijing-Tianjin-Hebei region of China

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Forest Ecosystems 2020年第4期7卷 704-715页

作者： tong sun Jianbo Qi Huaguo Huang State Forestry and Grassland Administration Key Laboratory of Forest Resources and Environmental Management Beijing Forestry UniversityBeijing 100083China

Background:The assessment of change in forest ecosystems,especially the change of canopy heights,is essential for improving global carbon estimates and understanding effects of climate *** lidar systems provide a unique opportunity to monitor changes in the vertical structure of ***’s Ice,Cloud and Land Elevation Satellites,ICESat-1 for the period 2003 to 2009,and ICESat-2(available since 2018),have collected elevation data over the Earth’s surface with a time interval of 10 *** this study,we tried to discover forest canopy changes by utilizing the global forest canopy height map of 2005(complete global coverage with 1 km resolution)derived from ICESat-1 data and the ATL08 land and vegetation products of 2019(sampling footprints with 17 m diameter)from ***:Our study revealed a significant increase in forest canopy heights of China’s Beijing-Tianjin-Hebei *** of unchanging areas for data consistency of two products show that the bias values decreased significantly from line-transect-level(−8.0 to 6.2 m)to site-level(^(−1).5 to 1.1 m),while RMSE values are still relatively high(6.1 to 15.2 m,10.2 to 12.0 m).Additionally,58%of ATL08 data are located in‘0m’pixels with an average height of 7.9 m,which are likely to reflect the ambitious tree planting programs in ***:Our study shows that it is possible,with proper calibrations,to use ICESat-1 and-2 products to detect forest canopy height changes in a regional *** expect that the approach presented in this study is potentially suitable to derive a fine-scale map of global forest change.

关键词： Forest height Global map ATL08 products Comparison Plantation

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The Thermal Decomposition of Calcium Carbonate

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Chinese Chemical Letters 2001年第8期12卷 745-746页

作者： Yu Ting ZHAO tong Shan sun Bing sun Department of Chemistry Shandong UniversityJinan 250100

The thermogravimetry(TG) and derivative thermogravimetry(DTG) curves of the thermal decomposition reaction of calcium carbonate have been measured at five different heating rates. The kinetic parameters and the reaction mechanism of the reaction were evaluated from analysis of the TG and DTG curves by using the Ozawa method, the combined integral and differential methods and the reduced equations derived by us.

关键词： Calcium carbonate kinetic parameters non-isothermal kinetics TG-DTG

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Bifunctional erdite rods as an effective flocculant and catalyst in electro-Fenton systems

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Progress in Natural Science:Materials International 2023年第4期33卷 518-525页

作者： tong sun Chengzhong sun Ying Wang Jiancong Liu Htet Oo Kaung Suiyi Zhu Zhongkai University of Agriculture and Engineering Crude Oil Shipping and Marketing Company Dagang Oilfield Company CNPC Supervision Company Jilin Oilfield Company CNPC School of Environment Northeast Normal University Lversheng Environmental Technology Company

Erdite rods were massively produced via a one-step alkaline heating route with the complete recycling of waste waterwork sludge. The sludge was a mixture of Fe, Mn, Al, and Si, but only Fe-bearing substances were converted as erdite rods. The erdite rods had 100 nm diameter and 1-5 μm length, and was hydrolysed as Fe-SH-rich flocs in wastewater. Its hydrolysis became slow in the presence of electric field but accelerated by adding PMS. pNitrophenol was targeted as organic pollutant to determine the rods performance. The removal efficiency of pnitrophenol was 7.4% by adding erdite rods, but up to 44.6% with the addition of erdite/PMS, and then dramatically increased to 98.7% in the electro-PMS/erdite system. Given that the free Fe was less than 30 mg/L,the surface Fe of Fe-SH-rich flocs predominated the PMS activation, in which the surface Fe enriched in electronic field and then was involved in the redox reaction of PMS and then reduced by the adjacent S on flocs. This enabled the recycling of Fe3+/Fe2+to activate PMS at high level. Thus, the erdite rods showed high p-nitrophenol removal efficiency in the electro-Fenton system in comparison with the other reported reagents, e.g. ferrous sulphate,ferbam, pyrite and FeS.

关键词： Erdite rods p-Nitrophenol Fenton reaction Wastewater treatment Flocculant

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Application of Non-invasive Microsensing System to Simultaneously Measure Both H^＋ and O2 Fluxes Around the Pollen Tube

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Journal of Integrative Plant Biology 2006年第7期48卷 823-831页

作者： Yue Xu tong sun Li-Ping Yin College of Life Sciences Capital Normal University Beijing 100037 China Younger USA Company Cary NC 27513 USA Vibrating Probe Facility Biology Department University of Massachusetts at Amherst MA 01003 USA

Various Ionic and molecular activities in the extraceUular environment are vital to plant cell physiological processes. A noninvasive microsensing system （NMS） based on either the scanning ion-selective electrode technique （SIET） or the scanning polarographlc electrode technique （SPET） is able to obtain information regarding the transportation of various Ions/molecules in Intact samples under normal physiological conditions. The two-probe simultaneous test system （2STS） Is an Integrated system composed of SIET, SPET, and a Xu-Kunkel sampling protocol. In the present study, 2STS was able to simultaneously measure fluxes of H^＋ and O2 of the Uly （Lillum Iongiflorum Thunb. cv. Ace） pollen tube while avoiding interference between the two probes. The results Indicate that the proton fluxes were effluxes, whereas the oxygen fluxes were Influxes, and they were closely correlated to each other surrounding the constitutive alkaline band region. Specifically, when the proton effluxes increased, the oxygen Influxes also increased. Therefore, the hypothesis of condensed active mitochondria existing in the alkalized area of the pollen tube proposed by Hepler＇s group is supported.

关键词： non-invasive microsensing system (NMS) oxygen fluxes pollen tube proton fluxes scanning ion-selective electrode technique (SIET) scanning polarographic electrode technique (SPET) two-probe simultaneous test system (2STS).

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Preparation and crystallization kinetics of micron-sized Mg（OH）2 in a mixed suspension mixed product removal crystallizer

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Frontiers of Chemical Science and Engineering 2013年第2期7卷 130-138页

作者： Xingfu SONG Kefeng tong Shuying sun Ze sun Jianguo YU National Engineering Research Center for Integrated Utilization of Salt Lake Resources East China University of Science and Technology Shanghai 200237 China

Magnesium hydroxide is an important chemi- cal, and is usually obtained from seawater or brine via precipitation process. The particle size distribution of magnesium hydroxide has great effects on the subsequent filtration and drying processes. In this paper, micron-sized magnesium hydroxide with high purity, large particle size and low water content in filter cake was synthesized via simple wet precipitation in a mixed suspension mixed product removal （MSMPR） crystallizer. The effects of reactant concentration, residence time and impurities on the properties of magnesium hydroxide were investigated by X-Ray diffraction （XRD）, Scanning Electron Micro- scopy （SEM） and Malvem laser particle size analyzer. The results show that NaOH concentration and residence time have great effects on the water content and particle size of Mg（OH）2. The spherical Mg（OH）2 with uniform diameter of about 30 μm was obtained with purity higher than 99% and water content less than 31%. Furthermore, the crystallization kinetics based on the population balance theory was studied to provide the theoretical data for industrial enlargement, and the simulation coefficients （R2） based on ASL model and C-R model are 0.9962 and 0.9972, respectively, indicating that the crystal growth rate of magnesium hydroxide can be well simulated by the size- dependent growth models.

关键词： magnesium hydroxide precipitation micron-sized crystallization kinetics

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A Novel Parameter-Optimized Recurrent Attention Network for Pipeline Leakage Detection

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IEEE/CAA Journal of Automatica Sinica 2023年第4期10卷 1064-1076页

作者： tong sun Chuang Wang Hongli Dong Yina Zhou Chuang Guan The authors are with the Sanya Offshore Oil&Gas Research Institute Northeast Petroleum UniversitySanya 572024 Artificial Intelligence Energy Research Institute Northeast Petroleum University Heilongjiang Provincial Key Laboratory of Networking and Intelligent Control Northeast Petroleum UniversityDaqing 163318China

Accurate detection of pipeline leakage is essential to maintain the safety of pipeline ***,deep learning(DL)has emerged as a promising tool for pipeline leakage detection(PLD).However,most existing DL methods have difficulty in achieving good performance in identifying leakage types due to the complex time dynamics of pipeline *** the other hand,the initial parameter selection in the detection model is generally random,which may lead to unstable recognition *** this reason,a hybrid DL framework referred to as parameter-optimized recurrent attention network(PRAN)is presented in this paper to improve the accuracy of ***,a parameter-optimized long short-term memory(LSTM)network is introduced to extract effective and robust features,which exploits a particle swarm optimization(PSO)algorithm with cross-entropy fitness function to search for globally optimal *** this framework,the learning representation capability of the model is improved and the convergence rate is ***,an anomaly-attention mechanism(AM)is proposed to discover class discriminative information by weighting the hidden states,which contributes to amplifying the normalabnormal distinguishable discrepancy,further improving the accuracy of *** that,the proposed PRAN not only implements the adaptive optimization of network parameters,but also enlarges the contribution of normal-abnormal discrepancy,thereby overcoming the drawbacks of instability and poor ***,the experimental results demonstrate the effectiveness and superiority of the proposed PRAN for PLD.

关键词： attention mechanism(AM) long shortterm memory(LSTM) parameter-optimized recurrent attention network(PRAN) particle swarm optimization(PSO) pipeline leakage detection(PLD)

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The cathode catalysts of hydrogen fuel cell:From laboratory toward practical application

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Nano Research 2023年第4期16卷 4365-4380页

作者： Shuang Cao tong sun Jin-Rong Li Qin-Zhu Li Chun-Chao Hou Qi sun College of Chemistry and Chemical Engineering Institute for Sustainable Energy and ResourcesQingdao UniversityQingdao 266071China School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China

Proton exchange membrane fuel cells(PEMFCs)have received a sustained world-wide attention owing to their promising applications based on clean ***,their widespread applications are still restricted by the sluggish oxygen reduction reaction(ORR)*** the past decades,significant efforts have been devoted to developing efficient ORR catalysts,which have been summarized in numerous previous ***,most of them mainly focused on ORR activity on the rotating disk electrode(RDE)level,which cannot truly represent the performance in real *** and showcasing efficient catalysts evaluated at the membrane electrode assembly(MEA)level is of vital *** this review,we first briefly showcased the recent development of ORR catalysts and then put more emphasis on the discussion of designing efficient catalysts at MEA and full-cell level,aiming to help stimulate more attention on their practical applications.

关键词： oxygen reduction reaction hydrogen energy membrane electrode assembly proton exchange membrane fuel cells

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Influence of Parasitic Parameters on Dynamic Threshold Voltage Hysteresis of Silicon Carbide MOSFETs

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2251-2262页

作者： Yumeng Cai tong sun Peng sun Zhibin Zhao Xuebao Li Hui Wang Zhong Chen Boyuan Cao the State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China the Department of Electrical Engineering University of ArkansasFayettevilleAR 72701USA the Electric Power Research Institute State Grid Shanghai Electric Power CompanyShanghai 200437China

Threshold voltage (V_(TH)) hysteresis affects the dynamic characteristics of silicon carbide (SiC) MOSFETs, whichin turn affects reliability of a device. In this paper, a dynamichysteresis curve is proposed as an evaluation method of theinfluence of V_(TH) hysteresis on the switching characteristics ofSiC MOSFETs. This method can eliminate the impact of triggerlevel and obtain the dynamic V_(TH). Furthermore, the influence ofparasitic parameters on dynamic V_(TH) hysteresis is theoreticallyanalyzed. Double pulse tests under different parasitic parametersare performed on three SiC MOSFETs with different gatestructures to verify the analysis. Results show that gate resistance(R_(G)) and source inductance (L_(S)) have more significant effectson dynamic V_(TH) hysteresis compared with gate inductance anddrain inductance. V_(TH) hysteresis phenomenon weakens withincrease of R_(G) or L_(S), which is related to device *** results presented in this paper can provide guidance forthe design of circuit parasitic parameters of SiC MOSFETs toregulate V_(TH) hysteresis.

关键词： Dynamic hysteresis curve parasitic parameters silicon carbide(SiC)MOSFETs switching characteristics threshold voltage hysteresis

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Detection of common wound infection bacteria based on FAIMS technology

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Frontiers of Computer Science 2019年第4期13卷 907-909页

作者： Shenyi QIAN Daiyi LI tong sun Bin YU School of Computer and Communication Engineering Zhengzhou University of Light Industry Zhengzhou 450002 China College of Communication Engineering Chongqing University Chongqing 400044 China

1 Introduction and main contributions In clinical surgery and postoperative rehabilitation, various types of wound infections can cause a variety of diseases, leading to further injury and even death of patients, which has become a common concern among doctors. The use of specific and rational antibiotics for patients is an important way to treat bacterial infections, while avoiding the abuse of antibiotics [1]. Therefore, rapid and reliable detection of infectious bacteria is the key premise of follow-up antibiotic treatment.

关键词： Introduction main treatment

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A Novel Magnetic Separation Oxygen-enriched Method and the Influence of Temperature and Magnetic Field on Enrichment

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Journal of Thermal Science 2007年第1期16卷 79-83页

作者： Li WANG Jun CAI Ping WU Lige tong Shufeng sun School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China

A novel oxygen-enriched method is presented. Using two opposite magnetic poles of two magnets with certain distance forms a magnetic space having a field intensity gradient near its borders. When air injected into the magnetic space outflows from the magnetic space via its borders, oxygen molecules in air will experience the interception effect of the gradient magnetic field, but nitrogen molecules will outflow without hindrance. Thereby the continuous oxygen enrichment is realized. The results show that the maximum increment of oxygen concentration reaches 0.49% at 298 K when the maximum product of magnetic flux density and field intensity gradient is 563T^2/m. The enrichment level is significantly influenced by the gas temperature and the magnetic field. The maximum increment of oxygen concentration drops to 0.16% when the gas temperature rises to 343 K, and drops to 0.09% when the maximum product of magnetic flux density and gradient is reduced to 101 T^2/m from 563 T^2/m.

关键词： magnetic separation oxygen enrichment oxygen separation gradient magnetic field magnetizing force

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