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Efficient Accumulation Integrated with Selective Degradation of Micropollutants Under Irradiation of Visible Light by the Size-Exclusion Effect of Metal-Organic Framework

SSRN

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SSRN 2023年

作者： Mi, Xin Li, Xiang Wang, Chongchen Wang, Bo Advanced Research Institute of Multidisciplinary Science School of Chemistry and Chemical Engineering Beijing Institute of Technology No. 5 South Street Zhongguancun Haidian District Beijing100081 China Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation Beijing Advanced Innovation Center for Future Urban Design Beijing University of Civil Engineering and Architecture Beijing100044 China

Developing multifunctional materials for efficiently removing pharmaceutical active compounds (PACs) in water matrix that coexisted with humic acid (HA) is in high demand. Water-stable metal-organic frameworks (MOFs) with high surface area and highly dispersed metallic sites are excellent adsorbents for uptaking PACs. However, limited catalytic activities of metal clusters under visible light hinder efficient degradation. In this study, the charge transfer properties (photocurrent increased 4.7 times) and visible-light absorption (bandgap 2.95~2.38 eV) of UiO-66 (Ce) were successfully improved by introducing a series of CdS using a facile post-synthesis modification (X % CdS@UiO-66 (Ce) (X = 10, 20, 30). h+ and •O2- were proved to be the major reactive species. The adsorption ability of the composites were 11.84 ~12.21 times higher than CdS and the overall removal efficiency were 1.31 and 2.18 times higher than that of UiO-66 (Ce) and CdS, respectively. Thanks to the porous structures, the composites retain high adsorption capacities for four negatively charged non-steroid anti-inflammatory drugs (NSAIDs) with low concentrations detected by HPLC-MSMS (e.g., 799.9 μg/g for diclofenac sodium) under interference of increasing amount of HA. This study offers a facile strategy to remove PACs and HA containing water effectively. © 2023, The Authors. All rights reserved.

关键词： Adsorption

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Two Degree-of-Freedom Dynamic Theoretical Model on Tile Thermal Protection System

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第1期36卷 139-145页

作者： HUANG Jie YAO Weixing KONG Bin YANG Jiayong WANG Man ZHANG Qingmao Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and Astronautics State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics AVIC Chengdu Aircraft Design and Research Institute

In order to study the dynamic behaviors of the thermal protection system(TPS)and dynamic strength of the strain-isolation-pad(SIP),a two degree-of-freedom dynamic theoretical model is presented under the acoustic excitation and base excitation. The tile and SIP are both considered as the elastic body and simplified as a mass point,a linear spring and a damping element. The theoretical solutions are derived,and the reasonability of theoretical model is verified by comparing the theoretical results with the numerical results. Finally,the influences on the dynamic responses of TPS by the structural damping coefficient of TPS,elasticity modulus and thickness of SIP are *** results show that the material with higher damping,and SIP with thicker size and lower elastic modulus should be considered to reduce the dynamic responses and intensify the security of TPS. The researches provide a theoretical reference for studying the dynamic behaviors of TPS and the dynamic strength of SIP. Besides,the dynamic theoretical model can be used as a quick analysis tool for analyzing the dynamic responses of TPS during the initial design phase.

关键词： thermal protection system dynamic theoretical model acoustic excitation base excitation

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Influence of reactor Core Sizes on Neutronics Performance of 250 Mwt Molten Salt reactor with Plutonium Grade Fuel

SSRN

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SSRN 2023年

作者： Waris, Abdul Wulandari, Cici Permana, Sidik Kinoshita, Motoyasu Research Center for Nuclear Reactor Technology Nuclear Energy Research Organization National Research and Innovation Agency Building No. 80 PUSPIPTEK South Tangerang15314 Indonesia Department of Physics Faculty of Mathematics and Natural Sciences Bandung Institute of Technology Indonesia Department of Nuclear Science and Engineering Faculty of Mathematics and Natural Sciences Bandung Institute of Technology Indonesia Nuclear Physics & Biophysics Research Division Department of Physics Faculty of Mathematics and Natural Sciences Bandung Institute of Technology Jl. Ganesa 10 Bandung40132 Indonesia Molten Salt Laboratory Inc. The University of Electro Communications-Alliance Center 1-1-1 Kojima-Cho Chofu Tokyo182-0026 Japan Faculty of Engineering Sciences Kyushu University 6‑1 Kasuga‑Koen Fukuoka Kasuga816‑8580 Japan

The influence of reactor core sizes and plutonium grades in neutronic performances on 250 MWt MSR have been investigated. The calculation is performed using PIJ and CITATION modules in the SRAC program and JENDL 4.0 as a nuclear data library. The reactor core size is varied into two different sizes (type-A and type-B), where the type-A reactor has double the size of type-B. The variation of Plutonium grades is employed in this study for several fuel cases. The fraction of Plutonium in the salt (PuF4) is optimized based on the obtained reactor criticality for 2000 days of operation time. The results indicate that reactor type-B has a higher PuF4 consumption, and the percentage of plutonium reduction becomes higher than reactor type-A. Additionally, the comparison of neutronic performance on the varied fuel cases is also analyzed in this paper. © 2023, The Authors. All rights reserved.

关键词： Thorium

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Study on surface pore characteristic and hydrophilicity of carbon materials in HTGR 27

Study on surface pore characteristic and hydrophilicity of c...

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27th International Conference on Nuclear Engineering: Nuclear Power Saves the World!, ICONE 2019

作者： Ma, Sheng-Chao Shen, Kai-Yue Yin, Hua-Qiang He, Xue-Dong Li, Jun Meng, Ying-Chao Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University Beijing100084 China Nuclear Power Design and Research Sub-institute Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China Chengdu610213 China Institute for Chemical and Bioengineering Department of Chemistry and Applied Biosciences Swiss Federal Institute of Technology Zurich Zurich8093 Switzerland

ISBN: (纸本)9784888983051

Lots of porous carbon materials, including boron-containing carbon (BC) and isostatic pressure graphite (IG-110), are used in high-temperature gas cooled reactor (HTGR). To prevent corrosion caused by carbon-water reaction at high temperature, water absorbed in the materials needs to be removed before the reactor operation. It has become the consensus of the researchers that the pore morphology of the material has an important influence on the physical adsorption and desorption process of the gas. Therefore, it is significant to explore the migration mechanism of moisture in carbon materials by studying the pore characteristics and hydrophilic properties of the material surface. Scanning electron microscopy (SEM) and contact angles tests were used to study the surface pore characteristic and hydrophilicity of BC and IG-110. The results of SEM scanning show that a large number of irregular micropores and cracks were found on the surface of BC, while the structure of IG-110 was more compact, and the size and number of pores were obviously smaller. 3 μL and 5 μL water drops were used to contact angle tests, it was found that the average contact angle of the BC surface with water droplets is 118.04°, which is greater than that of IG-110, measured as 112°. Finally, the water vapor absorption experiment of these two materials were carried out to verify that the pore structure and hydrophilicity have an effect on water absorption, and the pore structure has a more decisive effect on moisture absorption than the hydrophilicity. © 2019 American Society of Mechanical Engineers (ASME). All rights reserved.

关键词： Scanning electron microscopy

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design and Realization of Intelligent Airborne Information Processing Concept Simulation System

Design and Realization of Intelligent Airborne Information P...

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IEEE International Conference on High Performance Computing and Communications (HPCC)

作者： Jianchun Xie Linting Bai Qing Luo Aviation Key Laboratory of Science And Technology On Airborne And Missile-borne Computer AVIC Xi'an Aeronautics Computing Technique Research Institute Xi'an China College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Nanning China Shenyang Aircraft Design&Reserch Institute Shenyang China

Facing the development trend of future distributed cloud operations, intelligent operations, and the technical requirements of multi-machine collaborative operations in the aviation field, this paper further studies the unified data transmission and management of multiple platforms based on the research of the unified cloud intelligent combat system architecture. Distributed data storage and management, multi-platform open information processing resource management and other key technologies, on the basis of the principle prototype designed and implemented by ourselves, a set of conceptual simulation platforms have been constructed for the simulation and technical verification of the entire airborne information processing system.

关键词： Technical requirements Atmospheric modeling Systems architecture Collaboration Prototypes Information processing Market research

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Preferential Removal of the Carboxyl Group-Containing Emerging Contaminants and the Adsorption-Induced Degradation by Ce-Metal-Organic Framework

SSRN

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SSRN 2023年

Pharmaceuticals (e.g. nonsteroidal anti-inflammatory drugs (NSAIDs) and quinone antibiotics etc.) and perfluoroalkyl carboxylic acids (PFCAs) containing carboxyl groups are frequently detected emerging contaminants (ECs). However, their distinguished structures (aromatic and alkyl groups) bring challenges for developing materials for water purification. In this study, Ce-MOFs, with various topologies (UiO-66, MOF-808, Ce-BTC), were selected as the platform to compare the preferential adsorption coupled with subsequent degradation of 19 pharmaceuticals including NSAIDs and 5 PFCAs at trace amounts (μg/L). Results show that Ce-based MOFs with unsaturated coordinated sites effectively adsorbed two kinds of ECs, but the mechanisms differed. For PFCAs with increasing lengths of alkyl chains, log Kow can be correlated well (R2 = 0.87~ 0.99) with both the adsorption kinetics ln (v0) and capacities (Qe), indicating the hydrophobic interaction should be the major mechanism. In contrast, Ce-MOFs rapidly adsorbed the carboxylic group containing pharmaceuticals mainly through electrostatic interaction, ranking the excellent adsorbents reported so far (e.g., Qeofloxacin = 419.78 mg/g). Thanks to the series of reactive species (•OH, 1O2, •O2-and defects) generated under solar-light irradiation, higher adsorption capacities of aromatic NASIDs facilitated the selective decomposition in situ. Notably, the calculated adsorption capacities (Qe) of selected pharmaceuticals correlated well (R2 = 0.99) with the pseudo-first-order rate constants during photocatalytic degradation. This study offers helpful guidance for the preferential removal of ECs. © 2023, The Authors. All rights reserved.

关键词： Adsorption

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Emergent grain boundary phases in stressed polycrystalline thin films

arXiv

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arXiv 2022年

作者： Wang, Mengyuan Yan, Ruilin Han, Xiao Wang, Hailong Upmanyu, Moneesh CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern Mechanics CAS Center for Excellence in Complex System Mechanics University of Science and Technology of China Anhui Hefei230027 China Department of Mechanical and Industrial Engineering Northeastern University BostonMA02115 United States

The grain boundary (GB) microstructure influences and is influenced by the development of residual stresses during synthesis of polycrystalline thin films. Recent studies have shown that the frustration between the preferred growth direction and rotations of abutting crystals to local cusps in GB energies leads to internal stresses localized within nanoscopic surface layers around the valleys and ridges that form at emergent boundaries (eGBs). Using a combination of continuum frameworks, numerical analyses and all-atom simulations of bicrystal h111i copper films, we show that eGBs tune their surface morphology and rotation extent in response to external strains. Compression favors rotation to and growth of low energy GB phases (complexions) at eGB valleys while tension favors the transitions at eGB ridges, a reflection of the stress-induced mass efflux/influx that changes the energetic balance between interfacial and deformation energies. Molecular dynamics simulations of strained and growing bicrystal films reveal that the eGB phase transition is coupled to island formation at the surface triple junctions, providing a direct link between eGB phases and surface step flow. The interplay between eGB structure, morphology and mechanics emerges as a crucial ingredient for predictive understanding of stress and morphological evolution during film growth, with broad implications for multifunctional response of polycrystalline surfaces in a diverse range of surface phenomena such as surface mediated deformation, interfacial embrittlement, thermal grooving, stress corrosion, surface catalysis and topological conduction. © 2022, CC BY.

关键词： Residual stresses

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Fingerprinting 146 Chinese chestnut(Castanea mollissima Blume)accessions and selecting a core collection using SSR markers

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Journal of Integrative Agriculture 2021年第5期20卷 1277-1286页

作者： NIE Xing-hua WANG Ze-hua LIU Ning-wei SONG Li YAN Bo-qian XING Yu ZHANG Qing FANG Ke-feng ZHAO Yong-lian CHEN Xin WANG Guang-peng QIN Ling CAO Qing-qin Beijing Advanced Innovation Center for Tree Breeding by Molecular Design Beijing University of AgricultureBeijing 102206P.R.China College of Plant Science and Technology Beijing Key Laboratory for Agricultural Application and New TechniqueBeijing University of AgricultureBeijing 102206P.R.China College of Landscape Architecture Beijing University of AgricultureBeijing 102206P.R.China Chestnut Technology Experiment and Extension Station of Huairou District Beijing 102206P.R.China Shandong Institute of Pomology Shandong Academy of Agricultural SciencesTai’an 271000P.R.China Changli Institute of Pomology Hebei Academy of Agriculture and Forestry SciencesChangli 066600P.R.China

Chinese chestnut is an important nut tree around the *** the types of Chinese chestnut resources are abundant,resource utilization and protection of chestnut accessions are still very ***,we fingerprinted and determined the genetic relationships and core collections of Chinese chestnuts using 18 fluorescently labeled SSR markers generated from 146 chestnut *** analyses showed that these markers from the tested accessions are highly polymorphic,with an average allele number(N_(a))and polymorphic information content(PIC)of 8.100 and 0.622 per locus,*** these strongly distinguishing markers,we successfully constructed unique fingerprints for 146 chestnut accessions and selected seven of the SSR markers as core markers to rapidly distinguish different *** exploration of the genetic relationships among the five cultivar groups indicated that Chinese chestnut accessions are divided into three regional type groups:group I(North China(NC)and Northwest China(NWC)cultivar groups),group II(middle and lower reaches of the Yangtze River(MLY)cultivar group)and group III(Southeast China(SEC)and Southwest China(SWC)cultivar groups).Finally,we selected 45 core collection members which represent the most genetic diversity of Chinese chestnut *** study provides valuable information for identifying chestnut accessions and understanding the phylogenetic relationships among cultivar groups,which can serve as the basis for efficient breeding in the future.

关键词： Castanea mollissima SSR markers fingerprinting phylogeny core collections

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A quantitative variational phase field framework

arXiv

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arXiv 2023年

作者： Mukherjee, Arnab Warren, James A. Voorhees, Peter W. Center for Hierarchical Materials Design Northwestern University EvanstonIL60208 United States Material Measurement Laboratory National Institute of Standards and Technology GaithersburgMD20899 United States Department of Materials Science and Engineering Northwestern University EvanstonIL60208 United States Department of Engineering Sciences and Applied Mathematics Northwestern University EvanstonIL60208 United States

The finite solid-liquid interface width in phase field models results in non-equilibrium effects, including solute trapping. Prior phase field modeling has shown that this extra degree of freedom, when compared to sharp-interface models, results in solute trapping that is well captured when realistic parameters, such as interface width, are employed. However, increasing the interface width, which is desirable for computational reasons, leads to artificially enhanced trapping thus making it difficult to model departure from equilibrium quantitatively. In the present work, we develop a variational phase field model that guarantees a temporal decrease in the free energy with independent kinetic equations for the solid and liquid phases. Separate kinetic equations for the phase concentrations obviate the assumption of point wise equality of diffusion potentials, as is done in previous works. Non-equilibrium effects such as solute trapping, drag and interface kinetics can be introduced in a controlled manner in the present model. In addition, the model parameters can be tuned to obtain "experimentally-relevant" trapping while using significantly larger interface widths than prior efforts. A comparison with these other phase field models suggests that interface width of about three to twenty-five times larger than current best-in-class models can be employed depending upon the material system at hand leading to a speed-up by a factor of W(d+2), where W and d denote the interface width and spatial dimension, respectively. Finally the capacity to model non-equilibrium phenomena is demonstrated by simulating oscillatory instability leading to the formation of solute bands. © 2023, CC BY.

关键词： Free energy

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COUNTRY-SCALE CROPLAND MAPPING IN DATA-SCARCE SETTINGS USING DEEP LEARNING: A CASE STUDY OF NIGERIA

arXiv

引用

arXiv 2023年

作者： Gajardo, Joaquin Volpi, Michele Onwude, Daniel Defraeye, Thijs Empa Swiss Federal Laboratories for Material Science and Technology Laboratory for Biomimetic Membranes and Textiles Lerchenfeldstrasse 5 St. GallenCH-9014 Switzerland SDSC Swiss Data Science Center ETH Zurich and EPFL Switzerland Food Quality and Design Wageningen University & Research P.O. Box 17 Wageningen6700 AA Netherlands Institute of Agricultural Sciences ETH Zurich Universitätstrasse 2 Zurich8092 Switzerland

Cropland maps are a core and critical component of remote-sensing-based agricultural monitoring. These maps can provide dense and up-to-date information about agricultural development without requiring regular field surveys, which are particularly challenging to execute in regions with limited accessibility. Machine learning is an effective tool for large-scale agricultural mapping, but relies on geo-referenced ground-truth data for model training and testing, which can be scarce or time-consuming to obtain. In this study, we explore the usefulness of combining a global cropland dataset and a hand-labeled dataset to train machine learning models for generating a new cropland map for Nigeria in 2020 at 10 m resolution. We provide the models with pixel-wise time series input data from remote sensing sources such as Sentinel-1 and 2, ERA5 climate data, and DEM data, in addition to binary labels indicating cropland presence. We manually labeled 1827 evenly distributed pixels across Nigeria, splitting them into 50% training, 25% validation, and 25% test sets used to fit the models and test our output map. We evaluate and compare the performance of single- and multi-headed Long Short-Term Memory (LSTM) neural network classifiers, a Random Forest classifier, and three existing 10 m resolution global land cover maps (Google's Dynamic World, ESRI's Land Cover, and ESA's WorldCover) on our proposed test set. Given the regional variations in cropland appearance, we additionally experimented with excluding or sub-setting the global crowd-sourced Geowiki cropland dataset, to empirically assess the trade-off between data quantity and data quality in terms of the similarity to the target data distribution of Nigeria. We find that the existing WorldCover map performs the best with an F1-score of 0.825 and accuracy of 0.870 on the test set, followed by a single-headed LSTM model trained with our hand-labeled training samples and the Geowiki data points in Nigeria, with a F1-score of

关键词： Mapping

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