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Atmospheric and Oceanic Science Letters 2024年第5期17卷 47-53页

作者： Yumeng Liu Xianhong Meng Lin Zhao S-Y.Simon Wang Lixia Zhang Zhaoguo Li Chan Wang Yingying An Key laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouChina Zoige Plateau Wetlands Ecosystem Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouChina University of Chinese Academy of Sciences BeijingChina Utah Climate Center Utah State UniversityLoganUSA The State Key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina

Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal *** study investigates the influence of the East Asian westerly jet(EAWJ)on TRSR rainfall.A strong correlation is found between TRSR summer precipitation and the Jet Zonal Position Index(JZPI)of the EAWJ from 1961 to 2019(R=0.619,ppacific(CTP)significantly affects TRSR *** influence is mediated through the AEA via a Rossby wave train extending eastward along the EAWJ,and another south of 45°***,the NA–CTP Opposite Phase Index(OPI),which quantifies the difference between the summer mean sea surface temperatures of the NA and the CTP,is identified as a critical factor in modulating the strength of this teleconnection and influencing the zonal position of the EAWJ.

关键词： Summer precipitation East Asian subtropical westerly jet Three River Source Region Atlantic-Eurasian teleconnection

Enhancing the Surface Stability of Ni-Rich Layered Transition Metal Oxide Cathode Materials

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Chinese Journal of Structural Chemistry 2019年第12期38卷 2005-2008页

作者： HU Jiang-Tao ZHANG Ji-Guang College Energy and Environment Directorate Pacific Northwest National Laboratory

Rechargeable Li-ion batteries have gained prominence because they offer unparalleled high energy density and high voltage *** are already widely used in portable electronic devices and electric *** of the most promising cathode materials,the Ni-rich LiNixMnyCo1-x-yO2(x≥0.6)cathode(Ni-rich NMC)has been extensively studied because its high Ni content enables high specific capacity(more than 200 mAh/g)[1].

关键词： gained Transition Cathode

Ensemble-based uncertainty quantification for coordination and control of thermostatically controlled loads

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Journal of Control and Decision 2018年第2期5卷 148-168页

作者： Weixuan Li Jianming Lian Dave Engel Hong Wang pacific northwest national laboratory RichlandWAUSA

This work investigates an uncertainty quantification(UQ)framework that analyses the uncertainty involved in modelling control systems to improve control strategy *** framework involves solving four problems:identifying uncertain parameters,propagating uncertainty to the quantity of interest,data assimilation and making decisions under quantified uncertainties.A specific group of UQ approaches,known as the ensemble-based methods,are adopted to solve these *** UQ framework is applied to coordinating a group of thermostatically controlled loads,which relies on simulating a second-order equivalent thermal parameter model with some uncertain *** this uncertainty affects the prediction and the control of total power is *** study shows that uncertainty can be effectively reduced using the measurement of air ***,the control objective is achieved fairly accurately with a quantification of the uncertainty.

关键词： Uncertainty quantification ensemble-based method thermostatically controlled loads transactive control smart grid

A Hydrogen Iron Flow Battery with High Current Density and Long Cyclability Enabled Through Circular Water Management

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Energy & Environmental Materials 2023年第4期6卷 173-178页

作者： Litao Yan Yuyan Shao Wei Wang pacific northwest national laboratory 902 Battelle BoulevardRichland WA 99354USA

The hydrogen-iron(HyFe)flow cell has great potential for long-duration energy storage by capitalizing on the advantages of both electrolyzers and flow ***,its operation at high current density(high power)and over continuous cycling testing has yet to be *** this article,we discuss our design and demonstration of a water-management strategy that supports high current and long-cycling performance of a HyFe flow *** molecules associated with the movement of protons from the iron electrode to the hydrogen electrode are sufficient to hydrate the membrane and electrode at a low current density of 100 mA cm^(-2)during the charge *** higher charge current density,more aggressive measures must be taken to counter back-diffusion driven by the acid concentration gradient between the iron and hydrogen *** water-management approach is based on water vapor feeding in the hydrogen electrode and water evaporation in the iron electrode,thus enabling high current density operation of 300 mA cm^(-2).

关键词： acid concentration gradient energy storage flow battery hydrogen longcycling performance water management

Template-directed synthesis of nitrogen- and sulfur- codoped carbon nanowire aerogels with enhanced electrocatalytic performance for oxygen reduction

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Nano Research 2017年第6期10卷 1888-1895页

作者： Shaofang Fu Chengzhou Zhu Junhua Song Mark H. Engelhard Xiaolin Li Peina Zhang Haibing Xia Dan Du Yuehe Lin School of Mechanical and Materials Engineering Washington State University WA 99164 USA Environmental Molecular Science laboratory Pacific Northwest National Laboratory Richland WA 99354 USA Energy and Environmental Directory Pacific Northwest National Laboratory Richland WA 99354 USA State Key laboratory of Crystal Materials Shandong University Jinan 250100 China

Heteroatom doping, precise composition control and rational morphology design are efficient strategies for producing novel nanocatalysts for the oxygen reduction reaction （ORR） in fuel cells. Herein, a cost-effective approach to synthesize nitrogen- and sulfur-codoped carbon nanowire aerogels using a hard templating method is proposed. The aerogels prepared using a combination of hydrothermal treatment and carbonization exhibit good catalytic activity for the ORR in alkaline solution. At the optimal annealing temperature and mass ratio between the nitrogen and sulfur precursors, the resultant aerogels show comparable electrocatalytic activity to that of a commercial Pt/C catalyst for the ORR. Importantly, the optimized catalyst shows much better long-term stability and satisfactory tolerance for the methanol crossover effect. These codoped aerogels are expected to have potential applications in fuel cells.

关键词： heteroatom-doped carbons porous nanomaterials aerogels metal-free catalysts oxygen reduction reaction

Fabrication,characterization and optimization of high conductivity and high quality nanocrystalline molybdenum thin films

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Journal of Materials Science & Technology 2019年第11期35卷 2734-2741页

作者： Anil K.Battu Nanthakishore Makeswaran C.V.Ramana Center for Advanced Materials Research(CMR) University of Texas at El PasoEl PasoTX 79968USA Environmental Molecular Sciences laboratory(EMSL) Pacific Northwest National Laboratory(PNNL)RichlandWA 99352USA

The present study investigated the influence of substrate temperature(Ts)and working pressure(P(Ar))on tailoring the properties of nanocrystalline(nc)molybdenum(Mo)films fabricated by radio-frequency magnetron *** structural,morphological,electrical and optical properties of nc-Mo films were evaluated in *** Mo films exhibited(110)orientation with average crystallite size varying from 9 to 22(±1)nm on increasing *** with structural data,the electrical resistivity decreased from 55μΩcm to 10μΩcm,which is the lowest among all the Mo *** Mo films deposited under variable P(Ar).the(110)peak intensity decrement coupled with peak broadening on increasing P(Ar).Lower deposition pressure yielded densely packed thin films with superior structural properties along with low resistivity of 15μΩ*** conditions to produce high quality Mo films with excellent structural,morphological,electrical and optical characteristics for utilization in solar cells as back contact layers were identified.

关键词： Molybdenum Thin films Microstructure Electrical characteristics Optical properties Solar cells

Aerosol Indirect Effects on Warm Clouds in the Grid-Point Atmospheric Model of IAP LASG(GAMIL)

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Atmospheric and Oceanic Science Letters 2010年第4期3卷 237-241页

作者： Shi Xiang-Jun Wang Bin Liu Xiao-Hong Wang Ming-Huai Li Li-Juan Dong Li Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China pacific northwest national laboratory Richland Washington 99352 USA

Aerosol indirect effects on warm clouds are estimated in the Grid-point Atmospheric Model of the State Key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics(IAP LASG)(GAMIL) with a new two-moment cloud microphysics scheme using two different physically-based aerosol activation parameterizations:Abdul-Razzak and Ghan,and Nenes and *** annual global mean changes in shortwave cloud forcing from preindustrial times to present day(a measure of the aerosol indirect effects) estimated from these two parameterizations are remarkably similar:0.76 W m?2 with the Abdul-Razzak and Ghan parameterization,and 0.78 W m?2 with the Nenes and Seinfeld ***-based parameterizations can provide robust representations of aerosol effects on droplet nucleation,meaning that aerosol activation is no longer the most uncertain factor in modeling aerosol indirect effects.

关键词： aerosol indirect effect droplet nucleation atmospheric model GAMIL

Data-driven modeling of power generation for a coal power plant under cycling

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能源与人工智能(英文) 2023年第1期11卷 90-105页

作者： Himanshu Sharma Laurentiu Marinovici Veronica Adetola Herbert T.Schaef pacific northwest national laboratory RichlandWA 99354USA

Increased penetration of renewables for power generation has negatively impacted the dynamics of conventional fossil fuel-based power *** power plants operating on the base load are forced to cycle,to adjust to the fluctuating power *** results in an inefficient operation of the coal power plants,which leads up to higher operating *** overcome such operational challenge associated with cycling and to develop an optimal process control,this work analyzes a set of models for predicting power ***,the power generation is intrinsically affected by the state of the power plant components,and therefore our model development also incorporates additional power plant process variables while forecasting the power *** present and compare multiple state-of-the-art forecasting data-driven methods for power generation to determine the most adequate and accurate *** also develop an interpretable attention-based transformer model to explain the importance of process variables during training and *** trained deep neural network(DNN)LSTM model has good accuracy in predicting gross power generation under various prediction horizons with/without cycling events and outperforms the other models for long-term *** DNN memory-based models show significant superiority over other state-of-the-art machine learning models for short,medium and long range *** transformer-based model with attention enhances the selection of historical data for multi-horizon forecasting,and also allows to interpret the significance of internal power plant components on the power *** newly gained insights can be used by operation engineers to anticipate and monitor the health of power plant equipment during high cycling periods.

关键词： Deep learning Interpretable temporal fusion transformer Long short-term memory Coal power plant cycling

Identification of the non-stationarity of extreme temperature events and teleconnections with solar activity and large-scale atmospheric circulation: A case study in the Yangtze River Economic Belt

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Journal of Earth Science 2024年

作者： Lin Zhang Jingyun Ling Shengzhi Huang Hongbin Zhan Yi Wu Menggui Jin Qiang Huang State Key laboratory of Eco-hydraulics in northwest Arid Region， Xi'an University of Technology College of Design and Engineering， national University of Singapore Yinshanbeilu Grassland Eco-Hydrology national Observation and Research Station， China Institute of Water Resources and Hydropower Research Department of Geology and Geophysics， Texas A&M University， College Station School of Earth System Science， Tianjin University School of Environmental Studies， China University of Geosciences

In recent decades， extreme climate events have become a major problem worldwide. To understand the uncertainty in the response of extreme events to global warming， regional assessments are required for various climatic and geographic regions. The spatiotemporal distribution of extreme temperature events in the Yangtze River Economic Belt (YREB) from 1960 to 2019， including interannual changes and their teleconnections with solar activity and large-scale atmospheric circulation， were analyzed using eight indices of extreme temperature events. Over the past six decades， the climate in the YREB region has seen a warming trend， characterized by an increase in extreme warm events and a decrease in extreme cold events. The extreme temperature indices exhibit strong spatial variability. The warm extremes display a significant upward trend across the YREB， while cold extremes are primarily concentrated in the western part of the region. In recent decades， both warm and cold extremes have significant interannual variations， and these events predominantly oscillate over periods of less than four years. After 1985， the relationship between El Ni?o-Southern Oscillation (ENSO)， Arctic Oscillation (AO)， pacific Decadal Oscillation (PDO) and extreme temperature events has changed significantly compared with pre-1985， and the direction of the phase angle can determine the positive and negative effects of the two time-series. ENSO， AO and PDO mainly have positive impacts on extreme temperature events， with ENSO and AO exerting greater impacts than PDO. In contrast， solar activity mainly has a negative impact on these events. Furthermore， the notable interdecadal changes in extreme temperature events， especially warm extremes， may be caused by the shift in the PDO phase. Therefore， the results of the study are important for the YREB region to take effective measures to mitigate the potential impacts of human activities on regional warming.

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Carbon dioxide conversion to valuable chemical products over composite catalytic systems

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Journal of Energy Chemistry 2013年第3期22卷 368-374页

作者： Robert A.Dagle Jianli Hu Susanne B.Jones Wayne Wilcox John G.Frye James F.White Juyuan Jiang Yong Wang pacific northwest national laboratory RichlandWA 99352USA School of Automation Engineering Tianjin University of Technology pacific northwest national laboratory.Richland WA 99352USA Voiland School of Chemical Engineering and Bioengineering Washington State University

This paper reports an experimental study on catalytic conversion of carbon dioxide to methanol, ethanol and acetic acid. Satalysts having different catalytic functions were synthesized and combined in different ways to enhance the selectivity to desired products. The combined catalyst system possessed the following functions： methanol synthesis, Fischer-Tropsch synthesis, water-gas-shift and hydrogenation. Results showed that the methods of integrating these catalytic functions played an important role in achieving the desired product selectivity. We speculate that if methanol synthesis sites were located adjacent to the C--C chain growth sites, the formation rate of C2 oxygenates would be enhanced. The advantage of using a high temperature methanol catalyst PdZnA1 in the combined catalyst system was demonstrated. In the presence of PdZnA1 catalyst, the combined catalyst system was stable at 380 ~C. It was observed that, at high temperature, kinetics favored oxygenate formation. The results implied that the process can be intensified by operating at high temperature using Pd-based methanol synthesis catalyst. Steam reforming of the byproduct organics was demonstrated as a means to provide supplemental hydrogen. Preliminary process design, simulation, and economic analysis of the proposed CO2 conversion process were carded out. Economic analysis indicates how ethanol production cost was affected by the price of CO2 and hydrogen.

关键词： CO2 utilization syngas Fischer-Tropsch methanol higher alchohols ethanol acetic acid