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Chinese Science Bulletin 2011年第32期56卷 3480-3485页

作者： WU Xiao yan junjie Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites China Meteorological Administration Beijing 100081 China National Satellite Meteorological Center Beijing 100081 China

Based on the infrared radiation transfer model, the outgoing longwave radiation (OLR) and Channel 5 radiance of Fengyun-3B (FY-3B) satellite visible infrared radiometer (VIRR) were simulated for 3812 global soundings. Using regression analysis of the simulations, an inverse model, which connected the flux equivalent brightness temperature with the channel brightness temperature, was derived. By applying the model to the FY-3B VIRR L1 data, the global OLR data at the time of the passing of the FY-3B were processed. The quality of the data was validated by comparing it with that of the NOAA-18 satellite's advanced very high resolution radiometer (AVHRR). The validation results show root mean square errors in the range 10-13 W/M 2 when comparing the daily average OLR of the VIRR with that of the NOAA-18 AVHRR, and the correlation coefficients were in the range 0.97-0.98. The larger RMSE is mainly due to the different passing times of the two satellites for the specific locations on the Earth. An example of the OLR data and its preliminary applications are given.

关键词：红外辐射计向外长波辐射连接通道卫星辐射观测 OLR资料 AVHRR 估计

Experimental study on pressure and temperature distributions for low mass flux steam jet in subcooled water

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Science China(Technological Sciences) 2009年第6期52卷 1493-1501页

作者： junjie yan XinZhuang Wu DaoTong Chong State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an 710049 China

A low mass flux steam jet in subcooled water was experimentally *** transition of flow pattern from stable jet to condensation oscillation was observed at relatively high water *** axial total pressures,the axial and radial temperature distributions were measured in the jet *** results indicated that the pressure and temperature distributions were mainly influenced by the water *** correlations corrected with water temperature were given to predict the dimen-sionless axial pressure peak distance and axial temperature distributions in the jet region,the results showed a good agreement between the predictions and ***,the self-similarity property of the radial temperature was obtained,which agreed well with Gauss *** present work,all the dimensionless properties were mainly dependent on the water temperature but weakly on the nozzle size under a certain steam mass flux.

关键词： dimensionless self-similarity steam jet condensation temperature distribution total pressure

RNA editing machinery in plant organelles

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Science China(Life Sciences) 2018年第2期61卷 162-169页

作者： junjie yan Qunxia Zhang Ping Yin National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research Huazhong Agricultural University

RNA editing is a type of post-transcriptional modification that includes nucleotide insertion/deletion or conversion. Different categories of RNA editing have been widely observed in distinct RNAs from divergent organisms. In flowering plants, RNA editing usually alters cytidine to uridine in plastids and mitochondria, playing important roles in various plant developmental processes, including organelle biogenesis, adaptation to environmental changes, and signal transduction. Numerous studies have demonstrated that a number of factors are involved in plant RNA editing, such as pentatricopeptide repeat(PPR) proteins, multiple organelle RNA editing factors(MORF, also known as RIP), organelle RNA recognition motif(ORRM) containing proteins,protoporphyrinogen IX oxidase 1(PPO1) and organelle zinc finger 1(OZ1). These factors play diverse roles in plant RNA editing due to their distinct characteristics. In this review, we discuss the functional roles of the individual editing factors and their associations in plant RNA editing.

关键词： RNA editing editosome plant organelles

Optimization of cold-end system of thermal power plants based on entropy generation minimization

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Frontiers in Energy 2022年第6期16卷 956-972页

作者： Yue FU Yongliang ZHAO Ming LIU Jinshi WANG junjie yan State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China

Cold-end systems are heat sinks of thermal power cycles,which have an essential effect on the overall performance of thermal power *** enhance the efficiency of thermal power plants,multi-pressure condensers have been applied in some large-capacity thermal power ***,little attention has been paid to the optimization of the cold-end system with multi-pressure condensers which have multiple parameters to be ***,the design optimization methods of coldend systems with single-and multi-pressure condensers are developed based on the entropy generation rate,and the genetic algorithm(GA)is used to optimize multiple *** parameters,including heat transfer area of multi-pressure condensers,steam distribution in condensers,and cooling water mass flow rate,are optimized while considering detailed entropy generation rate of the cold-end *** results show that the entropy generation rate of the multi-pressure cold-end system is less than that of the single-pressure cold-end system when the total condenser area is ***,the economic performance can be improved with the adoption of the multi-pressure cold-end *** compared with the single-pressure cold-end system,the excess revenues gained by using dual-and quadruplepressure cold-end systems are 575 and 580 k$/a,respectively.

关键词： cold-end system entropy generation minimization optimization economic analysis genetic algorithm(GA)

A Review on Thermal Design of Liquid Droplet Radiator System

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Journal of Thermal Science 2021年第2期30卷 394-417页

作者： CHONG Daotong ZHU Maoguo ZHAO Quanbin CHEN Weixiong yan junjie State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China

Liquid Droplet Radiator (LDR) system is regarded as a quite promising waste heat rejection system for aerospace engineering.A comprehensive review on the state-of-the-art of LDR system was carried *** thermal design considerations of crucial components such as working fluid,droplet generator and collector,intermediate heat exchanger,circulating pump and return pipe were *** state-of-the-art of existing mathematical models of radiation and evaporation characteristics of droplet layer from literatures were ***,thermal designs of three LDR systems were *** weight and required planform area between the rectangular and triangular LDR systems were respectively compared and the evaporation models for calculating the mass loss were *** on the review,some prospective studies of LDR system were put forward in this paper.

关键词： Liquid Droplet Radiator(LDR)system thermal design considerations radiative heat transfer evaporation loss

Hydrogenation Behavior of Hydrogen Peroxide in a Microreactor

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China Petroleum Processing & Petrochemical Technology 2022年第4期24卷 29-35页

作者： Zhu Hongwei Sun Bing Jin yan Feng junjie Zhao Chenyang yan junjie Jiang Jie Xu Wei SINOPEC Research Institute of Safety Engineering Co. Ltd.Qingdao 266071 State Key Laboratory of Heavy Oil Processing China University of Petroleum Qingdao 266580

The hydrogenation of hydrogen peroxide is an unwanted side reaction in the direct synthesis of hydrogen peroxide and remains a problem to *** mechanism of this reaction has been studied with batch reactors but the slow heat and mass transfer in batch reactors hindered the understanding of its intrinsic *** this study,a microreactor is employed to investigate the parameters that influence the hydrogenation reaction,including flow rate,channel length,hydrogen pressure,solvent composition,and initial hydrogen peroxide *** activity of different catalysts was compared and the hydrogenation law was confirmed,providing guiding information to better control the hydrogenation process.

关键词： hydrogenation hydrogen peroxide microreactor hydrogenation decomposition law catalyst passivation

数据中心多能互补分布式能源系统设计与运行优化研究

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西安交通大学学报 2025年第1期59卷 93-104页

作者：任效效李小龙薛凯吴炫韩小渠王进仕严俊杰西安交通大学动力工程多相流国家重点实验室西安710049 中国电力工程顾问集团西北电力设计院有限公司西安710075

为实现数据中心的低碳转型和能效提升,提出了一种集成多种可再生能源和储能设备的多能互补分布式能源系统作为其供能系统。建立了包含生命周期成本、碳排放、能耗、电网购电率和热量浪费率等指标的优化目标体系。制定了两种考虑负荷特... 详细信息

为实现数据中心的低碳转型和能效提升,提出了一种集成多种可再生能源和储能设备的多能互补分布式能源系统作为其供能系统。建立了包含生命周期成本、碳排放、能耗、电网购电率和热量浪费率等指标的优化目标体系。制定了两种考虑负荷特征的运行策略,采用改进的多目标蝗虫优化算法对系统容量配置进行求解。为了分析优化目标和运行策略对系统优化的影响,通过组合不同优化目标和运行策略形成了多种优化设计方案,采用层次分析法和熵权法确定评价指标的权重,并利用多准则妥协解排序法进行评价排序。针对青海省某数据中心的案例,获得其能源系统的优化设计与运行方案。研究表明:运行策略主要影响吸收式制冷机和地源热泵的容量,而优化目标主要影响储能设备的容量;在相同的运行策略下,增加优化目标可提升系统的综合性能;对于不同的方案,生命周期成本、碳排放、能耗等基础优化目标值变化较小,而电网购电率和热量浪费率变化较大;通过实施五目标优化,即在基础优化目标的基础上增加热量浪费率、电网购电率,系统的综合性能得到了显著提升,其中热量浪费率和电网购电率分别降低了62.30%和25.92%,可再生能源发电占比增加了2%。

关键词：数据中心多能互补分布式能源系统优化设计运行策略多目标蝗虫优化算法

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TriCTI:an actionable cyber threat intelligence discovery system via trigger-enhanced neural network

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Cybersecurity 2022年第3期5卷 18-33页

作者： Jian Lu junjie yan Jun Jiang Yitong He Xuren Wang Zhengwei jiang Peian yang Ning Li Institute of Information Engineering Chinese Academy of SciencesBeijing 100093China School of Cyber Security University of Chinese Academy of SciencesBejing 100029China College of Information Engineering Capital Normal UniversityBeijing 100048China

The cybersecurity report provides unstructured actionable cyber threat intelligence(CTI)with detailed threat attack procedures and indicators of compromise(IOCs),e.g.,malware hash or URL(uniform resource locator)of command and control *** actionable CTI,integrated into intrusion detection systems,can not only prioritize the most urgent threats based on the campaign stages of attack vectors(i.e.,IOCs)but also take appropriate mitigation measures based on contextual information of the ***,the dramatic growth in the number of cybersecurity reports makes it nearly impossible for security professionals to find an efficient way to use these massive amounts of threat *** this paper,we propose a trigger-enhanced actionable CTI discovery system(TriCTI)to portray a relationship between IOCs and campaign stages and generate actionable CTI from cybersecurity reports through natural language processing(NLP)***,we introduce the“campaign trigger”for an effective explanation of the campaign stages to improve the performance of the classification *** campaign trigger phrases are the keywords in the sentence that imply the campaign *** trained final trigger vectors have similar space representations with the keywords in the unseen sentence and will help correct classification by increasing the weight of the *** also meticulously devise a data augmentation specifically for cybersecurity training sets to cope with the challenge of the scarcity of annotation data *** with state-of-the-art text classification models,such as BERT,the trigger-enhanced classification model has better performance with accuracy(86.99%)and F1 score(87.02%).We run TriCTI on more than 29k cybersecurity reports,from which we automatically and efficiently collect 113,543 actionable *** particular,we verify the actionability of discovered CTI by using large-scale field data from VirusTotal(VT).The results demonstrate that the threat

关键词： Actionable cyber threat intelligence Campaign trigger Indicators of compromise(IOCs) Natural language processing(NLP)

Experimental study on mercury content in flue gas of coal-fired units based on laser-induced breakdown spectroscopy

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Plasma Science and Technology 2020年第7期22卷 75-82页

作者： Kai RONG Zhenzhen WANG Ruomu HU Renwei LIU Yoshihiro DEGUCH junjie yan Jiping LIU State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049People’s Republic of China Graduate School of Technology Industrial and Social SciencesTokushima UniversityTokushima 770-8501Japan Moe Key Laboratory of Thermo-Fluid Science and Engineering Xi'an Jiaotong UniversityXi'an 710049People’s Republic of China

Accurate measurement of trace heavy metal mercury(Hg) in flue gas of coal-fired units is great significance for ecological and environmental *** gas was used to simulate the actual flue gas of a power plant in this study.A laser-induced breakdown spectroscopy(LIBS)system for Hg measurement in mixed gas was built to study the effect of mixed gas pressure,Hg concentration in mixed gas and delay time on Hg *** experimental results show that the appropriate low mixed gas pressure can obtain high Hg signal intensity and signal to noise *** Hg signal intensity and signal to noise ratio increased with the increase of Hg concentration in mixed *** Hg signal intensity and signal to noise ratio decreased with the increase in delay *** to the above results,the optimized measurement conditions can be *** Hg concentrations in mixed gas were quantitatively analyzed by the internal standard method and traditional calibration method *** relative error of prediction of the test sample obtained by the internal standard method was within 11.11%.The relative error of prediction of the traditional calibration method was less than 14.54%.This proved that the internal standard method can improve the accuracy of quantitative analysis of Hg concentration in flue gas using LIBS.

关键词： laser-induced breakdown spectroscopy flue gas trace heavy metal quantitative analysis

Shape-controlled synthesis of liquid metal nanodroplets for photothermal therapy

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Nano Research 2019年第6期12卷 1313-1320页

作者： junjie yan Xudong Zhang yang Liu yanqi Ye Jicheng Yu Qian Chen Jinqiang Wang Yuqi Zhang Quanyin Hu yang Kang Min yang Zhen Gu Joint Department of Biomedical Engineering University of North Carolina at Chapel Hill and North Carolina State UniversityRaleighNC 27695USA Molecular Imaging Center Key Laboratory of Nuclear MedicineMinistry of HealthJiangsu Key Laboratory of Molecular Nuclear MedicineJiangsu Institute of Nuclear MedicineWuxi 214063China Department of Bioengineering University of CaliforniaLos AngelesCA 90095USA California NanoSystems Institute University of CaliforniaLos AngelesCA 90095USA Department of Materials Science & Engineering North Carolina State UniversityRaleighNC 27695USA Jonsson Comprehensive Cancer Center University of CaliforniaLos AngelesCA 90095USA Center for Minimally Invasive Therapeutics University of CaliforniaLos AngelesCA 90095USA

The capping agents for liquid metal (LM) nanodroplets in aqueous solutions are restricted to thiol-containing and positively-charged molecules or ***,both thiolate-metal complex and electrostatic interaction are liable to detachment upon strong mechanical forces such as sonication,leading to limited stability and *** address this,we utilized ultrasmall water soluble melanin nanoparticles (MNPs) as the capping agent,which exhibited strong metal binding capability with the oxide layer of gallium based LMs and resulted in enhanced ***,shape-controlled synthesis of LM nanodroplets can be achieved by the incorporation of *** EGaln nanostructures including nanorice,nanosphere and nanorod were obtained by simply tuning the feed ratio,sonication time,and suspension *** these shapes,EGaln nanorice has the best photothermal conversion efficiency,which could be leveraged for photothermal therapy.

关键词： liquid metal melanin nanoparticles nanomedicine shape-controlled synthesis photothermal therapy