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Design and implementation of China Hydrogen Price Index system

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Clean Energy 2023年第1期7卷 148-156页

作者： Wei liu Yanming Wan Yan Zhang Qi Liu China Hydrogen Alliance Research Institute Co. LtdBeijing100007China Guohua Energy Investment Co. LtdBeijing100007China

Hydrogen will be an important part of China’s energy system in the future and an important carrier for energy-using terminals to realize green and low-carbon transformation.It is important to establish a nationwide hydrogen market to promote the healthy and orderly development of the hydrogen industry chain.The core is to form a complete hydrogen price mechanism and play a decisive role in the process of resource allocation by the market.In this paper,we have developed the framework of the‘China Hydrogen Price Index’system by establishing the‘Assessment+Collection’model,which covers four types of hydrogen:hydrogen,clean hydrogen,renewable hydrogen and high-purity hydrogen.The model considers the raw materials required for hydrogen production,fixed equipment,engineering construction costs and carbon prices,and conducts sensitivity analysis on the trends and influencing factors of national and regional hydrogen prices of multiple categories since 2018.The results show that,with respect to the level of hydrogen prices,fossil-energy-rich and renewable-energy-rich areas have more advantages than other regions.The price of raw materials is the main factor of the hydrogen price change,and the utilization hours of renewable energy and hydrogen production equipment have a key influence on the price of renewable hydrogen.Next,by establishing an index update mechanism,improving the standard system and building a trading platform,we can further exert the role of price signals and continue to promote the efficient and smooth expansion of the domestic hydrogen market.

关键词： hydrogen price index market price

A Full-Scale Optimization of a Crop Spatial Planting Structure and its Associated Effects

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Engineering 2023年第9期28卷 139-152页

作者： Qi Liu Jun Niu Taisheng Du Shaozhong Kang Center for Agricultural Water Research in China China Agricultural UniversityBeijing 100083China State Key Laboratory of Efficient Utilization of Agricultural Water Resources Beijing 100083China National Field Scientific Observation and Research Station on Efficient Water Use of Oasis Agriculture in Wuwei of Gansu Province Wuwei 733000China Key Laboratory of Agricultural Water Saving of the Ministry of Water Resources Beijing 100083China

Driven by the concept of agricultural sustainable development,crop planting structure optimization(CPSO)has become an effective measure to reduce regional crop water demand,ensure food security,and protect the environment.However,traditional optimization of crop planting structures often ignores the impact on regional food supply–demand relations and interprovincial food trading.Therefore,using a system analysis concept and taking virtual water output as the connecting point,this study proposes a theoretical CPSO framework based on a multi-aspect and full-scale evaluation index system.To this end,a water footprint(WF)simulation module denoted as soil and water assessment tool–water footprint(SWAT-WF)is constructed to simulate the amount and components of regional crop WFs.A multi-objective spatial CPSO model with the objectives of maximizing the regional economic water productivity(EWP),minimizing the blue water dependency(BWFrate),and minimizing the grey water footprint(GWFgrey)is established to achieve an optimal planting layout.Considering various benefits,a fullscale evaluation index system based on region,province,and country scales is constructed.Through an entropy weight technique for order preference by similarity to an ideal solution(TOPSIS)comprehensive evaluation model,the optimal plan is selected from a variety of CPSO plans.The proposed framework is then verified through a case study of the upper–middle reaches of the Heihe River Basin in Gansu province,China.By combining the theory of virtual water trading with system analysis,the optimal planting structure is found.While sacrificing reasonable regional economic benefits,the optimization of the planting structure significantly improves the regional water resource benefits and ecological benefits at different scales.

关键词： Planting structure optimization Full-scale evaluation index system Water footprint SWAT-WF module Interprovincial food trade Entropy weight TOPSIS

A Dual-spline Approach to Load Error Repair in a HEMS Sensor Network

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Computers, Materials & Continua 2018年第11期57卷 179-194页

作者： Xiaodong liu Qi Liu School of Computing Edinburgh Napier University10 Colinton RoadEdinburgh EH105DTUK

In a home energy management system(HEMS),appliances are becoming diversified and intelligent,so that certain simple maintenance work can be completed by appliances themselves.During the measurement,collection and transmission of electricity load data in a HEMS sensor network,however,problems can be caused on the data due to faulty sensing processes and/or lost links,etc.In order to ensure the quality of retrieved load data,different solutions have been presented,but suffered from low recognition rates and high complexity.In this paper,a validation and repair method is presented to detect potential failures and errors in a domestic energy management system,which can then recover determined load errors and losses.A Kernel Extreme Learning Machine(K-ELM)based model has been employed with a Radial Basis Function(RBF)and optimised parameters for verification and recognition;whilst a Dual-spline method is presented to repair missing load data.According to the experiment results,the method outperforms the traditional B-spline and Cubic-spline methods and can effectively deal with unexpected data losses and errors under variant loss rates in a practical home environment.

关键词： Electric load data analysis home energy management quality assurance and control

Identification of navigation characteristics of single otter trawl vessel using four machine learning models

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Journal of Oceanology and Limnology 2023年第3期41卷 1206-1219页

作者： Qi Liu Yunxia CHEN Haihong MIAO Yingbin WANG School of Fishery Zhejiang Ocean UniversityZhoushan 316022China Zhoushan Ecological Environment Bureau Putuo Branch Zhoushan 316100China Marine Fisheries Bureau of Putuo District Zhoushan 316105China

Fishing logbook records the fishing behaviors and other information of fishing vessels.However,the accuracy of the recorded information is often difficult to guarantee due to the misreport and concealment.The fishing vessel monitoring system(VMS)can monitor and record the navigation information of fishing vessels in real time,and it may be used to improve the accuracy of identifying the state of fishing vessels.If the VMS data and fishing logbook are combined to establish their relationships,then the navigation characteristics and fishing behavior of fishing vessels can be more accurately identified.Therefore,first,a method for determining the state of VMS data points using fishing log data was proposed.Secondly,the relationship between VMS data and the different states of fishing vessels was further explored.Thirdly,the state of the fishing vessel was predicted using VMS data by building machine learning models.The speed,heading,longitude,latitude,and time as features from the VMS data were extracted by matching the VMS and logbook data of three single otter trawl vessels from September 2012 to January 2013,and four machine learning models were established,i.e.,Random Forest(RF),Adaptive Boosting(AdaBoost),K-Nearest Neighbor(KNN),and Gradient Boosting Decision Tree(GBDT)to predict the behavior of fishing vessels.The prediction performances of the models were evaluated by using normalized confusion matrix and receiver operator characteristic curve.Results show that the importance rankings of spatial(longitude and latitude)and time features were higher than those of speed and heading.The prediction performances of the RF and AdaBoost models were higher than those of the KNN and GBDT models.RF model showed the highest prediction performance for fishing state.Meanwhile,AdaBoost model exhibited the highest prediction performance for non-fishing state.This study offered a technical basis for judging the navigation characteristics of fishing vessels,which improved the algorithm for judging the behavior of fishing vesse

关键词： vessel monitoring system(VMS) fishing logbook single otter trawler state identification machine learning

Research on carbon emissions embodied in China-Russia trade under the background of the Belt and Road

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Frontiers of Earth Science 2023年第2期17卷 576-588页

作者： Yang YU Yiming DU Wei XU Qi Liu School of Economics and Management Beijing University of Chemical TechnologyBeijing 100029China

Based on the latest China-Russia input-output data sets over the period from 2007 to 2015,this study quantified the flow of embodied carbon emissions in China-Russia trade using the emission embodied in bilateral trade(EEBT)approach.In addition,the structural decomposition analysis(SDA)was employed to identify the potential driving factors that affect embodied carbon in imports and exports.The results showed as follow.1)China was a net exporter of carbon emissions in bilateral trade between China and Russia during 2007–2015.Despite that the bilateral trade scale had expanded considerably,the net export volume of CO_(2)from China to Russia decreased from 13.21 Mt in 2007 to 4.45 Mt in 2015.2)From the perspective of different sectors,the metal manufacturing and the chemical sectors of China and Russia were the main sources of CO_(2)emissions.3)In terms of driving factors,it was found that the carbon emission coefficient was the main reason for contributing to embodied emission reduction.Moreover,the contribution rate of carbon emission coefficient to reduce the carbon emissions in imports reached to 95.26%,as well as 108.22%in exports.The bilateral trade scale was the main driver for the increase in embodied carbon emissions,and the contribution rate to embodied carbon emissions in imports and exports were 14.80%and 65.17%,respectively.4)This study argued that China and Russia should further optimize the energy structure and improve the energy efficiency and intermediate technology in the future.

关键词： embodied carbon emissions I-O model China-Russia trade SDA

A new type of cell related to organ movement for selfing in plants

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National Science Review 2023年第9期10卷 190-203页

作者： Yin-Zheng Wang Yan-Xiang Lin Qi Liu Jing liu Spencer C.H.Barrett State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of Sciences China National Botanical Garden College of Life Sciences University of Chinese Academy of Sciences College of Pharmacy Fujian University of Traditional Chinese Medicine Department of Ecology and Evolutionary Biology University of Toronto

Many plants employ osmotic and hydrostatic pressure to generate movement for survival,but little is known about the cellular mechanisms involved.Here,we report a new cell type in angiosperms termed ’contractile cells’ in the stigmas of the flowering plant Chirita pumila with a much-expanded rough endoplasmic reticulum(RER).Cryo-scanning electron microscopy and transmission electron microscopy analyses revealed that the RER is continuously distributed throughout the entirety of cells,confirmed by endoplasmic reticulum(ER)-specific fluorescent labeling,and is distinct from the common feature of plant ER.The RER is water-sensitive and extremely elongated with water absorption.We show that the contractile cells drive circadian stigma closing-bending movements in response to day-to-night moisture changes.RNA-seq analyses demonstrated that contractile cells have distinct molecular components.Furthermore,multiple microstructural changes in stigma movements convert an anti-selfing structure into a device promoting selfing—a unique cellular mechanism of reproductive adaptation for uncertain pollination environments.

关键词： stigma movement rough endoplasmic reticulum contractile cells circadian moisture changes reproductive transition

Modeling bubble column reactor with the volume of fluid approach:Comparison of surface tension models

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Chinese Journal of Chemical Engineering 2019年第11期27卷 2659-2665页

作者： Qi Liu Zhenghong Luo Department of Chemical Engineering College of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China

This work aims at comparing surface tension models in VOF(Volume of Fluid) modeling and investigating the effects of gas distributor and gas velocity. Hydrodynamics of a continuous chain of bubbles inside a bubble column reactor was simulated. The grid independence study was first conducted and a grid size of 1.0 mm was adopted in order to minimize the computing time without compromising the accuracy of the results. The predictions were validated by comparing the experimental studies reported in the literature. It was found that all surface tension models can describe the bubble rise and bubble plume in a column with slight deviations.

关键词： Bubble column reactor Computational fluid dynamics Volume of fluid method Surface tension models Gas distributor

Total nitrogen and community turnover determine phosphorus use efficiency of phytoplankton along nutrient gradients in plateau lakes

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Journal of Environmental Sciences 2023年第2期124卷 699-711页

作者： Yun Zhang Hucai Zhang Qi Liu Lizeng Duan qichao Zhou Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental SciencesYunnan UniversityKunming 650500China

Numerous studies support that biodiversity predict most to ecosystem functioning,but whether other factors display a more significant direct impact on ecosystem functioning than biodiversity remains to be studied.We investigated 398 samples of the phytoplankton phosphorus resource use efficiency(RUE_(P)=chlorophyll-a concentration/dissolved phosphate)across two seasons in nine plateau lakes in Yunnan Province,China.We identified the main contributors to phytoplankton RUEP and analyzed their potential influences on RUEP at different lake trophic states.The results showed that total nitrogen(TN)contributed the most to RUEP among the nine lakes,whereas community turnover(measured as community dissimilarity)explained the most to RUEP variation across the two seasons.Moreover,TN also influenced RUEP by affecting biodiversity.Species richness(SR),functional attribute diversity(FAD2),and dendrogram-based functional diversity(FDc)were positively correlated with RUEP in both seasons,while evenness was negatively correlated with RUEP at the end of the rainy season.We also found that the effects of biodiversity and turnover on RUEP depended on the lake trophic states.SR and FAD2 were positively correlated with RUEP in all three trophic states.Evenness showed a negative correlation with RUEP at the eutrophic and oligotrophic levels,but a positive correlation at themesotrophic level.Turnover had a negative influence on RUEP at the eutrophic level,but a positive influence at the mesotrophic and oligotrophic levels.Overall,our results suggested that multiple factors and nutrient states need to be considered when the ecosystem functioning predictors and the biodiversityecosystem functioning relationships are investigated.

关键词： Community turnover Biodiversity Phytoplankton Resource use efficiency Taxonomic diversity Total nitrogen

A new oxyapatite red phosphor Eu^(3+)-doped Ca_(3)Y_(7)(BO_(4))(SiO_(4))_(5)O:Synthesis,structure and luminescence properties

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Journal of Rare Earths 2022年第5期40卷 709-716,I0002页

作者： Tian Tian Wei liu Qi Liu Yan Zhang Yaoqing Chu Gan liu Jiayue Xu Institute of Crystal Growth School of Materials Science and EngineeringShanghai Institute of TechnologyShanghai 201418China Jiangsu Technology Innovation&C-V2X Academy Co. Ltd.Nanjing 210014China

A series of new oxyapatite red phosphors Ca_(3) Y_(7)(BO_(4)) (SiO_(4))_(5) O doped with different concentrations of Eu^(3+)were successfully synthesized by high temperature solid state method.The X-ray diffraction(XRD)Rietveld refinement results show that the structure of the phosphor belongs to space group P6_(3)/m and Eu^(3+)ion replaces Y^(3+)ion.The emission spectrum consists of the characteristic emission peaks corresponding to Eu^(3+)under the excitation of 274 nm and the dominant emission peak is at 614 nm(^(5)D_(0)→^(7)F_(2) of Eu^(3+)).The concentration quenching effect occurs and the optimized Eu^(3+)concentration is 4.0 mol%.The energy level diagram for luminous mechanism is also given and the non-radiative energy transfer mechanism between Eu^(3+)is mainly exchange interaction.The CIE coordinate is close to the ideal red light and the color purity is higher than 99.79%.Moreover,the phosphor exhibits moderate thermal stability because the photoluminescence intensity at 423 K is still maintained at higher than 78.97%of that at room temperature.The internal quantum efficiency of Ca_(3) Y_(7)(BO_(4)) (SiO_(4))_(5) O:4.0 mol%Eu^(3+)phosphor is 58.2%.A red light emitting diode(LED)device based on it can emit bright red light.The CCT values of the device are basically unchanged when driven by various bias current.The results show that Ca_(3) Y_(7)(BO_(4)) (SiO_(4))_(5) O:Eu^(3+)is a new type of oxyapatite red fluorescent material with good comprehensive performances.

关键词： Red phosphor Oxyapatite structure Eu3+ions doping LED device Rare earths