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water Science and Engineering 2024年第2期17卷 129-138页

作者： Guo-fen Hua Shang-qing Liu Xiang-dong Liu Jin-li Li Yue Fang Wen-ting Xie Xiang Xu College of water Conservancy and Hydroelectric Power Hohai UniversityNanjing 210098China College of renewable energy Hohai UniversityNanjing 210098China

Coastal wetlands are hotspots for nitrogen(N)cycling,and crab burrowing is known to transform N in intertidal marsh ***,the underlying mechanisms remain *** study conducted field experiments and used indoor control test devices to investigate the seasonal response of nitrogen to crab disturbance at the sediment-water interface in coastal tidal flat *** results showed that crab disturbance exhibited significant seasonality with large seasonal differences in cave density and *** to crab disturbance,nitrogen fuxes at the sediment-water interface were much greater in the box with crabs than in the box without *** summer,NH-N showed a positive flux from the sediment to the overlying water,but NO2-N and NOg-N showed positive fluxes from the sediment to the overlying water only in early *** winter,NH-N showed a positive flux from the sediment to the overlying water,but NO-N and NO,-N both exhibited positive and negative *** results indicated that the presence of crab burrows can cause the aerobic layer to move downward by approximately 8-15 cm in summer and directly promote nitrification at the sediment surface.

关键词： Coastal tidal flat wetland Crab disturbance Nitrogen flux Nitrification Denitrification Sediment-water interface

Evaluation of soil loss severity and ecological restoration approach for sustainable agriculture in the Hindu Kush, Karakoram and Himalaya region

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Journal of Mountain Science 2024年第5期21卷 1509-1521页

作者： Arshad ASHRAF Imran AHMAD Climate Energy and Water Research InstituteNational Agricultural Research Centre(NARC)Islamabad 44000Pakistan

Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya(HKH) region. The existing production of cereal crop grains has been reduced to one third of the potential crop grains production owing to land degradation and poor farming practices. It is necessary to assess risk of soil loss and identify appropriate controlling measures to address issues of low agriculture productivity and water insecurity in the region. In the present study, severity of soil loss was predicted using Revised Universal Loss Equation(RUSLE) and ecological measures were identified for sustainable mountain agriculture in the HKH region of Upper Indus Basin, Pakistan. Overall 62.6% area was found to have very low risk of soil loss, i.e., 100 t/(ha·yr) in about 6.8% and 7.4% areas respectively. The mean rate of soil loss was about 41.9 t/(ha·yr) in the Hindu Kush, 31.1 t/(ha·yr) in the Himalayas, 18.8 t/(ha·yr) in the Karakoram and overall 29.7 t/(ha·yr) in the three HKH ranges. As such no considerable measures have been adopted by the communities for restoration of the degraded areas except raising fruit/farm trees and supporting limited social forestry for their livelihoods. The slopes cleared for cultivation and susceptible to erosion may be stabilized through sowing/planting of multi-purpose plant species and formation of proper bench terraces. The conservation of forest ecosystem and pastures at higher elevations would help in reducing overland water flow, risk of flash flood hazard and minimizing sediment loads in the downstream. It is essential to adopt site-specific resource conservation techniques and restore possible ecosystem health for sustainable agriculture and economic developm

关键词： Climate change Erodibility Indus basin Land degradation Slope stabilization

Highly selective and eco-friendly dihydroisoquinoline synthesis via Cu/Co synergistic catalysis in Cu NPs@MOFs catalyst under mild conditions

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Science China Chemistry 2024年第5期67卷 1561-1568页

作者： Peng-Fei Guo Ze-Long Liang Yue-E Jiao Hang Xu Bin Zhao Key Laboratory of Advanced energy Material Chemistry Renewable Energy Conversion and Storage CenterDepartment of ChemistryNankai UniversityTianjin 300071China

3,4-Dihydroisoquinoline(DHIQ)is an important precursor used in the production of drugs for treating cancer,HIV,Alzheimer's disease,*** studies on DHIQ synthesis show low catalytic selectivity due to the susceptible over-oxidation feedstock of1,2,3,4-tetrahydroisoquinoline(THIQ),which often requires alkali ***,it is desirable yet challenging to explore a highly selective and efficient oxydehydrogenation capacity for DHIQ synthesis under eco-friendly reaction ***,a novel framework 1 was synthesized,exhibiting 1D channels with the size of 4.6 A×9.6 A and high solvent/p H/thermal stability.A stable framework allows it to encapsulate Cu nanoparticles(NPs)to form Cu NPs@1-x(x=1,2,3,and 4)with varying loading amounts of Cu NPs at 2.0 wt%,3.0 wt%,4.0 wt%,and 6.0 wt%,*** NPs@1-3 could selectively catalyze the reaction from THIQ to DHIQ with a high selectivity of 98%and a recorded turnover frequency(TOF)of 22.1 h-1under eco-friendly mild *** corresponding catalytic activity can maintain at least five recyclings and can be further applied to gram-scale ***,the efficient preparation of DHIQ catalyzed by Cu NPs@1-3 could be realized even under air ***,the anticancer molecule precursor synthesis of 6,7-dimethoxy-3,4-dihydroisoquinoline was also selectively catalyzed by Cu NPs@*** investigations revealed that high catalytic performance can be attributed to the stable framework and the synergistic catalytic effect of the loaded Cu NPs and Co metal *** importantly,this work represents the first example of MOF catalysts for selectively thermo-catalytic DHIQ synthesis and demonstrates a simple approach to obtain efficient catalysts for selective oxydehydrogenation in the production of unsaturated compounds.

关键词： metal-organic frameworks Cu NPs@MOFs 3 4-dihydroisoquinoline selective oxydehydrogenation synergistic catalysis

Numerical study of flow and thermal characteristics of pulsed impinging jet on a dimpled surface

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 106-117页

作者： Amin Bagheri Kazem Esmailpour Morteza Heydari renewable energy Research Center Damavand BranchIslamic Azad UniversityDamavandIran

This research comprehensively investigates the flow and thermal characteristics of a pulsating impinging jet over a dimpled *** analyzes the impact of key parameters(e.g.,inlet velocity pulsation functions,pulsation frequency,amplitude,dimple pitch,dimple depth,Reynolds number)on flow patterns and heat *** computational fluid dynamics and the Re-normalization group turbulence model are employed to accurately simulate complex turbulent flow *** and average heat transfer coefficients are calculated and compared to steady impingement cases,revealing the potential benefits of pulsation for heat transfer *** study also examines how pulsation-induced flow modulation and thermal mixing affect heat transfer *** indicate that combining fluctuating flow with a dimpled surface can improve heat transfer *** summary,increasing pulsation amplitude consistently enhances heat transfer,while the effect of frequency varies between impinging and wall jet zones.

关键词： Pulsating impinging jet Dimpled surface Heat transfer enhancement Pulsation frequency and amplitude Coherent structures

Visual and portable detection of metronidazole realized by metal-organic framework flexible sensor and smartphone scanning

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Chinese Chemical Letters 2024年第10期35卷 526-530页

作者： Xiangshuai Li Jian Zhao Li Luo Zhuohao Jiao Ying Shi Shengli Hou Bin Zhao Department of Chemistry Key Laboratory of Advanced Energy Materials Chemistry Renewable Energy Conversion and Storage Center (RECAST) Nankai University

Metronidazole （MNZ） is a type of antibiotic that can help people and animals cure bacterial in fections,however,abuse of MNZ has posed a threat to human ***,portable and vi sual detection of MNZ is meaningful for food safety and rational administration of drugs,bu full of ***,a porous three-dimensional Tb-based metal-organic framework (MOF{（CH3）2NH2·[Tb5（TDA）8（H2O）2]·6DMF·2C2H5OH}_n（TDA-Tb） with good solvent and p H stabilities was pre pared,and the framework possesses one-dimensional channels with a diameter of 12 A along the c-axis Experiment results suggest that the synthesized TDA-Tb can selectively and sensitively detect MNZ in water,and the limit of detection （LOD） is as low as 4.1×10-7mol/***,a flexible sensor TDA Tb-M was also constructed by incorporating TDA-Tb into membrane materials for convenient *** the TDA-Tb-M firstly realized portable and visual detection of MNZ through smartphone scanning,which may inspire more probes with wide application ranges.

关键词： Antibiotic Lanthanide Luminescence Metal-organic framework Sensor

Pixel-level crack segmentation of tunnel lining segments based on an encoder–decoder network

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Frontiers of Structural and Civil Engineering 2024年第5期18卷 681-698页

作者： Shaokang HOU Zhigang OU Yuequn HUANG Yaoru LIU State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing 100084China China renewable energy Engineering Institute Beijing 100120China State Key Laboratory of Stimulation and Regulation of water Cycles in River Basins China Institute of Water Resources and Hydropower ResearchBeijing 100038China Hunan Provincial water Resources Development&Investment Co. Ltd.Changsha 410007China

Regular detection and repair for lining cracks are necessary to guarantee the safety and stability of *** development of computer vision has greatly promoted structural health *** study proposes a novel encoder–decoder structure,CrackRecNet,for semantic segmentation of lining segment cracks by integrating improved VGG-19 into the U-Net *** image acquisition equipment is designed based on a camera,3-dimensional printing(3DP)bracket and two laser rangefinders.A tunnel concrete structure crack(TCSC)image data set,containing images collected from a double-shield tunnel boring machines(TBM)tunnel in China,was *** data preprocessing operations,such as brightness adjustment,pixel resolution adjustment,flipping,splitting and annotation,2880 image samples with pixel resolution of 448×448 were *** model was implemented by Pytorch in PyCharm processed with 4 NVIDIA TITAN V *** the experiments,the proposed CrackRecNet showed better prediction performance than U-Net,TernausNet,and *** paper also discusses GPU parallel acceleration effect and the crack maximum width quantification.

关键词： tunnel lining segment crack detection semantic segmentation convolutional neural network encoder-decoder structure

Crystallization management of CsPbI2Br perovskites by PbAc2-incorporated twice spin-coating process for efficient and stable CsPbI2Br perovskite solar cells

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Journal of energy Chemistry 2024年第10期97卷 419-428页

作者： Yu Liu Kun Lang Huifang Han Huijing Liu Yao Fu Pengchen Zou Yinhui Lyu Jia Xu Jianxi Yao State Key Laboratory of Alternate Electrical Power System with renewable energy Sources Beijing Key Laboratory of Energy Safety and Clean Utilization North China Electric Power University

CsPbI2Br perovskite solar cell has been extensively studied due to its exceptional thermal stability and relatively stable perovskite phase ***,the presence of bromine leads to a rapid crystallization rate of CsPbI2Br films,resulting in small grain size and high defect ***,CsPbI2Br demonstrates poor light absorption due to its wide ***,it is crucial to control the crystallization rate and increase the film thickness to reduce defect density,enhance light absorption,and improve photovoltaic *** this study,we utilized a PbAc2-incorporated twice spincoating（PTS） process to address these ***,PbAc2was added to the CsPbI2Br precursor solution to form a CsPbI2Br film,which was then coated with the CsPbI2Br precursor solution to produce the PTS film,Ac-can delay the perovskite crystallization,leading to the formation of thicker and denser CsPbI2Br ***,lone-pair electrons of the oxygen atom provided by Ac-formed coordination bonds with under-coordinated Pb2+ions to fill halogen ion vacancies,thereby reducing the defect ***,the PTS CsPbI2Br device achieved a peak power conversion efficiency（PCE） of 16.19% and maintained 96.7% of its initial PCE over 1500 h at room temperature under 25% relative humidity without any encapsulation.

关键词： Crystallization management CsPbI2Br PbAc2 Perovskite solar cells Twice spin-coating process

An active learning workflow for predicting hydrogen atom adsorption energies on binary oxides based on local electronic transfer features

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Green energy & Environment 2024年第10期9卷 1489-1496页

作者： Wenhao Jing Zihao Jiao Mengmeng Song Ya Liu Liejin Guo International Research Center for renewable energy State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Department of energy and Power Engineering Shandong University of Technology

Machine learning combined with density functional theory（DFT） enables rapid exploration of catalyst descriptors space such as adsorption energy, facilitating rapid and effective catalyst screening. However, there is still a lack of models for predicting adsorption energies on oxides,due to the complexity of elemental species and the ambiguous coordination environment. This work proposes an active learning workflow（Le NN） founded on local electronic transfer features（e） and the principle of coordinate rotation invariance. By accurately characterizing the electron transfer to adsorption site atoms and their surrounding geometric structures, Le NN mitigates abrupt feature changes due to different element types and clarifies coordination environments. As a result, it enables the prediction of *H adsorption energy on binary oxide surfaces with a mean absolute error（MAE） below 0.18 e V. Moreover, we incorporate local coverage（θl） and leverage neutral network ensemble to establish an active learning workflow, attaining a prediction MAE below 0.2 e V for 5419 multi-*H adsorption structures. These findings validate the universality and capability of the proposed features in predicting *H adsorption energy on binary oxide surfaces.

关键词： Machine learning Adsorption energy Binary oxide Electron transfer Active learning

Exploring commercial water electrolyser systems: a data-based analysis of product characteristics

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CLEAN energy 2024年第1期8卷 126-133页

作者： Jin, Xin You, Shi Petersen, Marianne Riofrio, Jonathan Thakur, Soumya Traeholt, Chresten Feng, Zhijian Tech Univ Denmark Dept Wind & Energy Syst DK-2800 Lyngby Denmark Siemens Gamesa renewable energy AS DK-7330 Brande Denmark

The urgency for energy transition is evident through the increasing demand for new technologies such as water electrolysers (WEs), which have the potential to generate green hydrogen using renewable electricity. This paper aims to provide a comprehensive overview of the technical capabilities of commercially available WE system products. The analysis is based on publicly accessible data gathered from 28 WE manufacturers worldwide with a total of 186 products, focusing on technology types and various technical characteristics of each WE system, including capacity, footprint, hydrogen output pressure, hydrogen purity and conversion rate. The analysis reveals that the current WE system solutions in the market exhibit diverse and varied characteristics. Further, there is a lack of standardized product specifications adopted by manufacturers. This underscores the urgent need for the development of frameworks and standards. Implementing such standards is crucial for enhancing clarity and understanding, facilitating efficient comparisons and selection processes, and supporting the future advancement of WE technologies and WE-enabled Power-to-X applications on a global scale. A comprehensive overview of the technical capabilities of commercially available water electrolysis system products is presented. The analysis is based on publicly accessible data gathered from manufacturers worldwide, focusing on technology types and technical characteristics, including capacity, conversion rate, footprint, hydrogen output pressure, hydrogen purity and efficiency. Graphical Abstract

关键词： data analysis hydrogen Power-to-X standards water electrolyser system energy

Laboratory Implementation of Direct Torque Controller based Speed Loop Pseudo Derivative Feedforward Controller for PMSM Drive

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 12-21页

作者： Prabhakaran Koothu Kesavan Umashankar Subramaniam Dhafer J.Almakhles IEEE renewable energy Laboratory Department of Electrical EngineeringPrince Sultan UniversityRiyadh 12435Saudi Arabia

This paper,evaluate the effectiveness of a proposed speed loop pseudo derivative feedforward(PDFF)controller-based direct torque controller(DTC)for a PMSM drive against the performance of existing PI speed controller-based DTC and hysteresis current controller(HCC).The proposed PDFF-based speed regulator effectively reduces oscillation and overshoot associated with rotor angular speed,electromagnetic torque,and stator *** case studies,one using forward-to-reverse motoring operation and the other involving reverse-to-forward braking operation,has been validated to show the effectiveness of the proposed control *** proposed controller's superior performance is demonstrated through experimental verification utilizing an FPGA controller for a 1.5 kW PMSM drive laboratory prototype.

关键词： Direct torque control Pseudo derivative feedforward controller Permanent magnet synchronous motor(PMSM)