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Spatiotemporal evolution of urban carbon emission performance in China and prediction of future trends

Journal of Geographical Sciences 2020年第5期30卷 757-774页

作者： WANG Shaojian gao shuang HUANG Yongyuan SHI Chenyi Guangdong Provincial Key Laboratory of Urbanization and Geo-simulation School of Geography and PlanningSun Yat-sen UniversityGuangzhou 510275China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China

Climate change resulting from CO_2 emissions has become an important global environmental issue in recent *** carbon emission performance is one way to reduce carbon *** carbon emission performance has been discussed at the national and industrial levels,city-level studies are lacking due to the limited availability of statistics on energy *** this study,based on city-level remote sensing data on carbon emissions in China from 1992–2013,we used the slacks-based measure of super-efficiency to evaluate urban carbon emission *** traditional Markov probability transfer matrix and spatial Markov probability transfer matrix were constructed to explore the spatiotemporal evolution of urban carbon emission performance in China for the first time and predict long-term trends in carbon emission *** results show that urban carbon emission performance in China steadily increased during the study period with some ***,the overall level of carbon emission performance remains low,indicating great potential for improvements in energy conservation and emission *** spatial pattern of urban carbon emission performance in China can be described as"high in the south and low in the north,"and significant differences in carbon emission performance were found between *** spatial Markov probabilistic transfer matrix results indicate that the transfer of carbon emission performance in Chinese cities is stable,resulting in a"club convergence"***,neighborhood backgrounds play an important role in the transfer between carbon emission performance *** on the prediction of long-term trends in carbon emission performance,carbon emission performance is expected to improve gradually over ***,China should continue to strengthen research and development aimed at improving urban carbon emission performance and achieving the national energy conservation and emission reducti

关键词： urban carbon emission performance super-efficiency SBM model spatial Markov chain spatiotemporal patterns trend prediction China

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Hydrous cerium oxides coated glass fiber for efficient and long-lasting arsenic removal from drinking water

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Journal of Advanced Ceramics 2021年第2期10卷 247-257页

作者： Ronghui Li Weiyi Yang shuang gao Jianku Shang Qi Li School of Gemology and Material Technology Hebei GEO UniversityShijiazhuang050031China Key Laboratory of Advanced Technologies of Materials(Ministry of Education) School of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu610031China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

A novel arsenic adsorbent with hydrous cerium oxides coated on glass fiber cloth(HCO/GFC)was *** HCO/GFC adsorbents were rolled into a cartridge for arsenic removal *** to the large pores between the glass fibers,the arsenic polluted water can flow through *** arsenic removal performance was evaluated by testing the equilibrium adsorption isotherm,adsorption kinetics,and packed-bed *** pH effects on arsenic removal were *** test results show that HCO/GFC filter has high As(Ⅴ)and As(Ⅲ)removal capacity even at low equilibrium *** more toxic As(Ⅲ)in water can be easily removed within a wide range of solution p H without *** contaminated ground-water from Yangzong Lake(China)was used in the column *** typical breakthrough conditions(the empty bed contact time,EBCT=2 min),arsenic researched breakthrough at over 24,000 bed volumes(World Health Organization(WHO)suggested that the maximum contaminant level(MCL)for arsenic in drinking water is 10 mg/L).The Ce content in the treated water was lower than 5 ppb during the column test,which showed that cerium did not leach from the HCO/GFC material into the treated *** relationship between dosage of adsorbents and the adsorption kinetic model was also clarified,which suggested that the pseudo second order model could fit the kinetic experimental data better when the adsorbent loading was relatively low,and the pseudo first order model could fit the kinetic experimental data better when the adsorbent loading amount was relatively high.

关键词： hydrous cerium oxide(HCO) glass fiber cloth(GFC) column test adsorption kinetics adsorption mechanism

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Microstructural evolution and stress state related to mechanical properties of electron beam melted Ti-6Al-4V alloy modified by laser shock peening

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Journal of Materials Science & Technology 2020年第15期47卷 153-161页

作者： Liang Lan Xinyuan Jin shuang gao Bo He Yonghua Rong Research Center of High-temperature Alloy Precision Forming School of Material EngineeringShanghai University of Engineering ScienceShanghai 201620China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

This work characterizes microstructural evolutions of electron beam melted(EBM) Ti-6 Al-4 V alloy modified via laser shock peening(LSP).The depth stress distribution and tensile properties of EBM Ti-6 Al-4 V alloy were measured before and after *** results indicate that microstructure consists of β phase with 7.2%±0.4% vol.% and balance α lamellar in EBM sample,and the α lamella was refined into nano-equiaxed grains and submicro-equiaxed grains after *** dominant refinement mechanism is revealed during *** faults were found in the LSP-treated sample,and their corresponding planes were determined as(0001) basal plane,(1010) prismatic plane,and(1011) pyramidal plane obtained by high resolution transmission electron *** subgrains and high-angle grains formed during dynamic recrystallization were identified by selected area electron diffraction *** LSP treatment produces a significantly residual compressive stress approximately-380 MPa with the depth of compressive stress layer reaching 450 μ*** and elongation of the EBM sample were significantly increased after *** strength and ductility enhancements are attributed to compre s sive stress,grain refinement and grain gradient distribution of α phase.

关键词： Electron beam melting Ti-6Al-4V alloy Laser shock peening Microstructural evolution Stress state Mechanical properties

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液质联用技术鉴定至宝三鞭丸化学成分

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中成药 2024年第1期46卷 161-169页

作者：高文雅赵海誉高双荣赵小亮焦玥刘洋王志国高畅李涛杜茂波中国中医科学院中药研究所北京100700 中国中医科学院医学实验中心北京100700

目的建立HPLC-LTQ-Orbitrap MS和HPLC-QQQ MS/MS法分析至宝三鞭丸化学成分。方法采用分段供试品制备的前处理方式、高分辨质谱数据依赖的采集模式、HPLC-MS/MS靶向成分采集等综合研究策略鉴定成分。分析采用Waters BEH HSS T3色谱柱(2.1... 详细信息

目的建立HPLC-LTQ-Orbitrap MS和HPLC-QQQ MS/MS法分析至宝三鞭丸化学成分。方法采用分段供试品制备的前处理方式、高分辨质谱数据依赖的采集模式、HPLC-MS/MS靶向成分采集等综合研究策略鉴定成分。分析采用Waters BEH HSS T3色谱柱(2.1 mm×100 mm,1.8μm);流动相0.1%甲酸水-乙腈,梯度洗脱;体积流量0.3 mL/min;柱温30℃;电喷雾离子源(ESI);正负离子扫描。结果共鉴定出82个化合物,包括有机酸类18个、黄酮类17个、萜类及皂苷类11个、色原酮类8个、苯乙醇苷类4个、生物碱类3个、香豆素类3个、木脂素类2个、蒽醌类2个,其中30个通过与对照品保留时间及碎片离子信息比对而确认。结论本研究初步鉴定了至宝三鞭丸化学成分,为该制剂质量控制、作用机制研究提供了有力的支撑。

关键词：至宝三鞭丸化学成分 HPLC-LTQ-Orbitrap MS HPLC-QQQ MS

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Influence of multiple laser shock peening treatments on the microstructure and mechanical properties of Ti-6Al-4V alloy fabricated by electron beam melting

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International Journal of Minerals,Metallurgy and Materials 2022年第9期29卷 1780-1787页

作者： Liang Lan Ruyi Xin Xinyuan Jin shuang gao Bo He School of Material Engineering Shanghai University of Engineering ScienceShanghai 201620China Research Center of High-temperature Alloy Precision Forming Shanghai University of Engineering ScienceShanghai 201620China

Laser shock peening(LSP)is an attractive post-processing method to tailor surface microstructure and enhance mechanical performances of additive manufactured(AM)*** effects of multiple LSP treatments on the microstructure and mechanical properties of Ti-6Al-4V part produced by electron beam melting(EBM),as a mature AM process,were studied in this ***,surface topography,residual stress,and tensile performance of EBM-manufactured Ti-6Al-4V specimens were systematically analyzed subjected to different LSP *** distribution of porosities in EBM sample was assessed via X-ray computed *** results showed that EBM samples with two LSP treatments possessed a lower porosity value of 0.05%compared to the value of 0.08%for the untreated *** strength of EBM samples with two LSP treatments was remarkably raised by 12%as compared with the as-built *** grains ofαphase were refined in near-surface layer,and a dramatic increase in the depth and magnitude of compressive residual stress(CRS)was achieved in EBM sample with multiple LSP *** grain refinement ofαphase and CRS with larger depth were responsible for the strength enhancement of EBM samples with two LSP treatments.

关键词： additive manufacturing laser shock peening electron beam melting residual stress Ti-6Al-4V alloy mechanical properties

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面向多类型土壤有机碳定量反演的天基高光谱探测参数研究

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土壤 2024年第3期56卷 639-645页

作者：李泽鑫高爽王昌昆刘国华胡登辉中国科学院微小卫星创新研究院上海201203 中国科学院大学北京100049 中国科学院南京土壤研究所南京210008

星载高光谱仪器的光谱通道以及光谱分辨率和信噪比等核心参数设置直接影响土壤有机碳定量反演精度。本研究开展了卫星载荷光谱分辨率、信噪比、光谱特征波段对不同土壤类型有机碳反演影响的研究,提出了基于大气传输模型、光谱分辨率分... 详细信息

星载高光谱仪器的光谱通道以及光谱分辨率和信噪比等核心参数设置直接影响土壤有机碳定量反演精度。本研究开展了卫星载荷光谱分辨率、信噪比、光谱特征波段对不同土壤类型有机碳反演影响的研究,提出了基于大气传输模型、光谱分辨率分析模型、信噪比分析模型、特征波段的提取分析模型以及偏最小二乘回归反演模型的面向不同土壤类型有机碳监测的高光谱卫星“地面-大气-仪器-观测-反演”全链路仿真分析方法,实现了土壤类型、大气效应、仪器特性参数、反演方法的耦合影响分析。结果表明:①3种类型土壤有机碳反演的最佳光谱分辨率均在10~20 nm。②不同土壤类型对观测的信噪比需求不同。对于Phaeozem的有机碳监测,较另外两种土壤有更高的信噪比需求。③在不同特征波段提取分析方法下所需的最佳光谱分辨率和信噪比一致。不同类型土壤光谱数据提取出的特征波段不同,其中反演效果最佳的土壤类型为Chernozem,特征波段数为26个,R^(2)=0.8265,RMSE=3.4389 g/kg。④反演模型与仪器特性参数无耦合关系,同一类型土壤不同反演算法的最佳光谱分辨率和信噪比需求一致。⑤Chernozem有机碳最佳反演参数需求为光谱分辨率15 nm,信噪比大于506.66,特征波段提取数为26个;Kastanozem有机碳最佳反演参数需求为光谱分辨率17 nm,信噪比大于331.42,特征波段提取数为22个;Phaeozem有机碳最佳反演参数需求为光谱分辨率15 nm,信噪比大于432.51,特征波段提取数为19个。

关键词：天基高光谱探测土壤有机碳监测大气传输模型光谱分辨率信噪比特征波段提取基于变量优选法

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基于DNV规范的玻璃纤维复合材料软管保护结构强度仿真研究

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复合材料科学与工程 2024年第7期 93-99页

作者：高爽李想文子彦刘晓彬初星澎中海石油(中国)有限公司深圳分公司深圳518000 中海油深圳海洋工程技术服务有限公司深圳518000 北京玻钢院复合材料有限公司北京102101

玻璃纤维复合材料因具有质轻高强、耐腐蚀的材料特点,在过去二十年里,被海外油田公司广泛应用于水下油气生产设施的防护,并取得成熟的工程应用。本文针对国产玻璃纤维复合材料软管保护罩,结合保护罩在水下的功能,应用有限元ANSYS软件建... 详细信息

玻璃纤维复合材料因具有质轻高强、耐腐蚀的材料特点,在过去二十年里,被海外油田公司广泛应用于水下油气生产设施的防护,并取得成熟的工程应用。本文针对国产玻璃纤维复合材料软管保护罩,结合保护罩在水下的功能,应用有限元ANSYS软件建立国产玻璃纤维复合材料软管保护罩的三维模型,从沙坡堆积、渔网拖挂和落物冲击三方面分析保护罩的强度,并依据DNV规范进行安全评定。仿真分析与试验对比分析表明,该保护罩强度满足规范要求,与试验结论吻合,可为今后的国产玻璃纤维复合材料水下防护结构设计提供参考。

关键词：水下生产系统玻璃纤维复合材料仿真分析软管保护罩强度

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基于电流源型变频器的电机长线驱动方法

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自动化技术与应用 2024年第10期43卷 176-180页

作者：高爽张忠容慧娴中海石油(中国)有限公司深圳分公司广东深圳518000 深圳市行健自动化股份有限公司广东深圳518000

为解决因电机运行环境干扰信号过多、各项运行指标配比不均衡导致长线驱动稳定性差的问题,提出一种基于电流源型变频器的驱动方法。先建立电机同步运行模型,求解在不同的时间节点下电机定子、转子以及转动角等各项参数的同步变动关系,... 详细信息

为解决因电机运行环境干扰信号过多、各项运行指标配比不均衡导致长线驱动稳定性差的问题,提出一种基于电流源型变频器的驱动方法。先建立电机同步运行模型,求解在不同的时间节点下电机定子、转子以及转动角等各项参数的同步变动关系,然后将该关系值作为长线驱动的初步参照,分别设计单闭环和多闭环驱动机制,最后采用电流源型变频器参照控制电机线路电流和电压的极限变化,通过变频器阈值调节使得电压和电流驱动达到平衡状态,以平衡值为阈值建立驱动器。实验数据表明,所提方法长线驱动性能表现较佳,电机运行稳定性强。

关键词：电流源型变频器电机长线驱动同步运行模型变频器阈值多闭环驱动

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Possible Streams of the Globular Clusters in the Galaxy

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Chinese Journal of Astronomy and Astrophysics 2007年第1期7卷 111-119页

作者： shuang gao Bi-Wei Jiang Yong-Heng Zhao Department of Astronomy Beijing Normal University Beijing 100875 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

We aim to retrieve ghost streams under the assumption that all the globular clusters in our Galaxy were formed in very early merge events. Our results are based on two speculations： that the specific energy and angular momentum of the globular clusters after merge are not changed in the course of evolution and that the globular clusters with a common origin would stay in the same orbit plane as the parent galaxy. After taking into account the apogalacticum distance of the orbits, we suggest with some Confidence five possible streams. The number of streams is consistent with the previous results. Three of the four well established members of the Sagittadus stream were found to be in one of our streams. Several other globular clusters in our result were also thought to come from accretion by previous researchers. The orbital parameters of the streams are derived, which provide a way to test whether these streams are true with the help of more accurate measurement of proper motions of the globular clusters.

关键词： globular clusters general-Galaxy formation-Galaxy halo

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Fabrication of ultrafine ZnFe2O4 nanoparticles for efficient photocatalytic reduction CO2 under visible light illumination

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Journal of Materials Science & Technology 2018年第12期34卷 2331-2336页

作者： Jun xiao Weiyi Yang shuang gao Caixia Sun Qi Li Environment Functional Materials Division Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academy of SciencesShenyong 110016China University ofChineseAcademy of Sciences Beijing 100049China Division of Energy and Environment Graduate School of ShenzhenTsinghua UniversityShenzhen 518055China Key Laboratory of New Metallic Functional Materials and Advanced Surface Engineering in Universities of Shandong Qingdao Binhai UniversityQingdao 266555China School of Mechanical and Electronic Engineering Qingdao Binhai UniversityQingdao 266555China

A one-pot, solvent-thermal process was used to create the ultrafine ZnFe2O4nanoparticles *** the solvent-thermal process, the in situ self-forming NaCl not only served as a "cage" to confine the ion diffusion, but also acted as a microreactor for nanocrystallite growth. An average particle size of ～10 nm and a high-specific surface area of～112.9 m2/g were observed for the ultrafine ZnFe2O4nanoparticles Owing to the synergistic effect of ultrafine particle size, the full utilization of the visible light region and high conduction band(CB) position, ultrafine ZnFe2O4photocatalyst displayed an efficient photocatalytic CO2reduction under visible light illumination. Besides, the ultrafine ZnFe2O4photocatalyst showed high production selectivity for CH3CHO and C2H5OH generation in aqueous CO2/NaHCO3solution. This work may provide a new idea for the synthesis of new high-efficiency photocatalysts.

关键词： Ultrafine nanoparticles Photocatalytic CO_2 reduction Visible light ZnFe_2O_4 photocatalyst In situ self-formed "cage"

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