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A Novel Layered Double Hydroxide and Dodecyl Alcohol Assisted PCM Composite with High Latent Heat Storage Capacity and Thermal Conductivity

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Journal of Thermal Science 2024年第2期33卷 537-547页

作者： AL-AHMED Amir SARI Ahmet KHAN Firoz AL-RASHEIDI Masoud Hekimoğlu Gökhan AFZAAL Mohammad A.ALSULAMI Ahmed DAFALLA Hatim SALHI Billel A.ALSULAIMAN Fahad interdisciplinary research center for Renewable Energy and Power Systems(IRC-REPS) King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Metallurgical and Material Engineering Karadeniz Technical UniversityTrabzon61080Turkey Maths and Natural Sciences Division Higher Colleges of TechnologyP.O.Box 7947SharjahUnited Arab Emirates Department of Mechanical Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Core research Facilities King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia interdisciplinary research center for membranes and water security King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia

Dodecyl alcohol(DDA) is a promising solid-liquid phase change material(PCM) due to its favorable latent heat storage(LHS) ***,the leakage issue of PCM in a melted state during the heating period and low thermal conductivity restricts its utilization potential in thermal energy storage(TES) *** the same context,the present work aims to overcome the leakage issue and improve the thermal conductivity of the *** this in mind,a novel leak-proof layered double hydroxide(LDH)/DDA composite PCM is proposed through a solution-based impregnation *** leak-proof impregnation ratio of the DDA impregnated within the cavities of the synthesized Al/Fe-LDH was determined to be 60%.Detailed morphological,physicochemical,and thermal properties of the fabricated composite were studied by scanning electron microscopy(SEM),Fourier transforms infrared(FTIR) spectroscopy,X-ray diffraction(XRD)spectroscopy,differential scanning calorimetry(DSC),thermalgravimetric analysis(TGA),and thermal cycling *** results show that the LDH/DDA composite has a suitable phase change temperature(about 20℃) for passive solar thermal management of building *** composite PCM showed high LHS enthalpy(about136 J/g),good thermal stability,and cycling LHS *** also showed nearly 152% higher thermal conductivity compared to that of pure DDA,ultimately reducing the melting and solidification time of the pure DDA by 44.9% and 45.5%,respectively.

关键词： dodecyl alcohol layered double hydroxide composite PCM thermal conductivity thermal energy storage(TES)

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Multiple pollutants from crop and livestock production in the Yangtze River: status and challenges

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 134-139,I0005页

作者： Lihua MA Shiyang LI Linfa FANG Xuanjing CHEN Ran XIAO Xiaoxuan SU Zhaolei LI Zhaohai BAI Lin MA Prakash LAKSHMANAN Xinping CHEN interdisciplinary research center for Agriculture Green Development in Yangtze River Basin College of Resources and EnvironmentSouthwest UniversityChongqing 400715China water Systems and Global Change Group Wageningen University&Research6708 PB Wageningenthe Netherlands Key Laboratory of Agricultural water Resources Center for Agricultural Resources ResearchInstitute of Genetic and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China Key Laboratory of Sugarcane Biotechnology and Genetic Improvement(Guangxi) Ministry of Agriculture and Rural AffairsGuangxi Key Laboratory of Sugarcane Genetic ImprovementSugarcane Research InstituteGuangxi Academy of Agricultural SciencesNanning 530007China Queensland Alliance for Agriculture and Food Innovation University of QueenslandSt Lucia 4067Australia

The rapid increase in the proportion of cash crops and livestock production in the Yangtze River Basin has led to commensurate increases in fertilizer and pesticide inputs. Excessive application of chemical fertilizer, organophosphorus pesticides and inappropriate disposal of agricultural waste induced water pollution and potentially threaten Agriculture Green Development(AGD). To ensure food security and the food supply capacity of the Yangtze River Basin, it is important to balance green and development, while ensuring the quality of water bodies. Multiple pollutants affect the transfer, adsorption, photolysis and degradation of each other throughout the soil-plant-water system. This paper considers the impact of multi-pollutants on the nitrogen and phosphorus cycles especially for crops, which are related to achieving food security and AGD. It presents prospective on theory, modeling and multi-pollutant control in the Yangtze River Basin for AGD that are of potential value for other developing regions.

关键词： Agriculture Green Development crop production livestock production multi-pollutant models multiple pollutants Yangtze River Basin

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Secure Transmission of Compressed Medical Image Sequences on Communication Networks Using Motion Vector watermarking

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Computers, Materials & Continua 2024年第3期78卷 3283-3301页

作者： Rafi Ullah Mohd Hilmi bin Hasan Sultan Daud Khan Mussadiq Abdul Rahim Computer and Information Sciences Department Universiti Teknologi PETRONASBandar Seri Iskandar Perak32610Malaysia Department of Computer Science National University of TechnologyIslamabad46000Pakistan interdisciplinary research center for Intelligent Secure Systems King Fahd University of Petroleum and MineralsDammam31261Saudi Arabia

Medical imaging plays a key role within modern hospital management systems for diagnostic *** methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all while upholding image ***,an increasing number of hospitals are embracing cloud computing for patient data storage,necessitating meticulous scrutiny of server security and privacy ***,considering the widespread availability of multimedia tools,the preservation of digital data integrity surpasses the significance of compression *** response to this concern,we propose a secure storage and transmission solution for compressed medical image sequences,such as ultrasound images,utilizing a motion vector watermarking *** watermark is generated employing an error-correcting code known as Bose-Chaudhuri-Hocquenghem(BCH)and is subsequently embedded into the compressed sequence via block-based motion *** the process of watermark embedding,motion vectors are selected based on their magnitude and phase *** embedding watermarks,no specific spatial area,such as a region of interest(ROI),is used in the *** embedding of watermark bits is dependent on motion *** reversible watermarking allows the restoration of the original image sequences,we use the irreversible watermarking *** reason for this is that the use of reversible watermarks may impede the claims of ownership and legal *** restoration of original data or images may call into question ownership or other legal *** peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)serve as metrics for evaluating the watermarked image *** all images,the PSNR value exceeds 46 dB,and the SSIM value exceeds *** results substantiate the efficacy of the proposed technique in preserving data integrity.

关键词： Block matching algorithm(BMA) compression full-search algorithm motion vectors ultrasound image sequence watermarking

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High-resolution short-term prediction of the COVID-19 epidemic based on spatial-temporal model modified by historical meteorological data

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Fundamental research 2024年第3期4卷 527-539页

作者： Bin Chen Ruming Chen Lin Zhao Yuxiang Ren Li Zhang Yingjie Zhao Xinbo Lian Wei Yan Shuoyuan Gao College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000China Collaborative Innovation center of Western Ecological security Lanzhou UniversityLanzhou 730000China

In the global challenge of Coronavirus disease 2019(COVID-19)pandemic,accurate prediction of daily new cases is crucial for epidemic prevention and socioeconomic *** contrast to traditional local,one-dimensional time-series data-based infection models,the study introduces an innovative approach by formulating the short-term prediction problem of new cases in a region as multidimensional,gridded time series for both input and prediction targets.A spatial-temporal depth prediction model for COVID-19(ConvLSTM)is presented,and further ConvLSTM by integrating historical meteorological factors(Meteor-ConvLSTM)is refined,considering the influence of meteorological factors on the propagation of *** correlation between 10 meteorological factors and the dynamic progression of COVID-19 was evaluated,employing spatial analysis techniques(spatial autocorrelation analysis,trend surface analysis,etc.)to describe the spatial and temporal characteristics of the *** the original ConvLSTM,an artificial neural network layer is introduced to learn how meteorological factors impact the infection spread,providing a 5-day forecast at a 0.01°×0.01°pixel *** results using real dataset from the 3.15 outbreak in Shanghai demonstrate the efficacy of Meteor-ConvLSTM,with reduced RMSE of 0.110 and increased R^(2) of 0.125(original ConvLSTM:RMSE=0.702,R^(2)=0.567;Meteor-ConvLSTM:RMSE=0.592,R^(2)=0.692),showcasing its utility for investigating the epidemiological characteristics,transmission dynamics,and epidemic development.

关键词： COVID-19 Prediction ConvLSTM Refined prediction Meteorological factors Spatial-temporal analysis

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Greenhouse gas emissions mitigation and economic viability of sugar crops in China

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Frontiers of Agricultural Science and Engineering 2024年第3期11卷 397-408,I0004页

作者： Linsheng YANG Xiaozhong WANG Wushuai ZHANG Prakash LAKSHMANAN Yan DENG Xiaojun SHI Xinping CHEN Fusuo ZHANG interdisciplinary research center for Agriculture Green Development in Yangtze River Basin College of Resources and EnvironmentSouthwest UniversityChongqing 400716China Key Laboratory of Low-carbon Green Agriculture in Southwestern China(Ministry of Agriculture and Rural Affairs) Southwest UniversityChongqing 400716China Rice research Institute Anhui Academy of Agricultural SciencesHefei 230031China Key Laboratory of Sugarcane Biotechnology and Genetic Improvement(Guangxi) Ministry of Agriculture and Rural AffairsGuangxi Key Laboratory of Sugarcane Genetic ImprovementGuangxi Academy of Agricultural SciencesSugarcane Research InstituteGuangxi Academy of Agricultural SciencesNanning 530007China center for Resources Environment and Food SecurityChina Agricultural UniversityBeijing 100193China

Climate change mitigation is a major challenge of human ***,to this end,many countries including China are committed to achieving carbon neutrality within a few *** is a major sugarcane and sugar beet producing country and has one of the largest carbon footprint for sugarcane and sugar beet production globally.A comprehensive study was conducted on sugarcane and sugar beet crops grown in China for greenhouse gas(GHG)emissions mitigation potential,economic crop production from a sustainable sugar production ***-term trend analysis showed that yield and GHG emissions of sugarcane and sugar beet crops increased but the ratio of income to cost *** equation model analysis revealed nitrogen fertilizer and labor as the major drivers of GHG emissions for both sugarcane and sugar *** sugarcane and sugar beet,the path coefficient of N fertilizer were‒0.964 and‒0.835 and that of labor were 0.771 and 0.589,*** transitioning the current cropping system to an improved model with optimized labor,N input and machinery use,the GHG emissions and total annual cost of sugarcane and sugar beet production can be reduced by 32%and 24%,respectively,by 2030,compared to a business-as-usual *** is the first integrated and comparative study of environmental and economic sustainability of sugarcane and sugar beet production in *** findings will enable all stakeholders of Chinese sugarcane and sugar beet industries to transform them into environmentally and economically sustainable sugar production.

关键词： Economic profits GHG emissions labor input nitrogen input sugar

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Review on current development of polybenzimidazole membrane for lithium battery

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Journal of Energy Chemistry 2024年第4期91卷 579-608页

作者： Yonggui Deng Arshad Hussain Waseem Raza Xingke Cai Dongqing Liu Jun Shen College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060GuangdongChina interdisciplinary research center for Hydrogen Technologies and Carbon Management(IRC-HTCM) King Fahd University of Petroleum&MineralsKFUPM Box 504031261 DhahranSaudi Arabia Institute for Advanced Study Shenzhen UniversityShenzhen 518060GuangdongChina

With the rapid development of portable technology,lithium batteries have emerged as potential candidates for high-performance energy storage systems owing to their high energy density and cycling *** the key components of a lithium battery system,the separator plays a critical role as it directly influences the battery performance benchmark(cycling performance and safety).However,traditional polyolefin separators(polypropylene/polyethylene)are unable to meet the demands of highperformance and safer battery systems due to their poor electrolyte compatibility,thermal runaways,and ultimate growth of *** contrast,membranes fabricated using polybenzimidazole(PBI)exhibit excellent electrolyte wettability and outstanding thermal dimensional stability,thus holding great potential as separators for high-performance and high-safety *** this paper,we present a comprehensive review of the general requirements for separators,synthesis technology for separators,and research trends focusing PBI membranes in lithium batteries to alleviate the current commercial challenges faced by conventional polyolefin *** addition,we discuss the future development direction for PBI battery separators by considering various factors such as production cost,ecological footprint,preparation technology,and battery component *** exploring these perspectives,we aim to promote the continued application and exploration of PBI-based materials to advance lithium battery technology.

关键词： Lithium batteries Separators Porous separators Polybenzimidazole Membrane

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The role of morphology on the electrochemical CO_(2) reduction performance of transition metal-based catalysts

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Journal of Energy Chemistry 2023年第10期85卷 198-219,I0007页

作者： Umar Mustapha Chidera C.Nnadiekwe Maria Abdulkarim Alhaboudal Umar Yunusa Abdulhakam Shafiu Abdullahi Ismail Abdulazeez Ijaz Hussain Saheed A.Ganiyu Abdulaziz A.Al-Saadi Khalid Alhooshani Department of Chemistry King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia interdisciplinary research center for Refining&Advanced Chemicals King Fahd University of Petroleum&MineralsDhahran 31261Saudi Arabia interdisciplinary research center for membranes and water security King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

The continued increase in population and the industrial revolution have led to an increase in atmospheric carbon dioxide(CO_(2)) concentration. Consequently, developing and implementing effective solutions to reduce CO_(2) emissions is a global priority. The electrochemical CO_(2) reduction reaction(CO_(2)RR) is strongly believed to be a promising alternative to fossil fuel-based technologies for the production of value-added chemicals. So far, the implementation of CO_(2)RR is hindered by associated electrochemical reactions, such as low selectivity, hydrogen evolution reaction(HER), and additional overpotential induced in some cases. As a result, it is necessary to conduct a timely evaluation of the state-of-the-art strategies in CO_(2)RR, with a focus on the engineering of the electrocatalytic systems. Catalyst morphology is one factor that plays a critical role in overcoming these drawbacks and significantly contributes to enhancing product selectivity and Faradaic efficiency(FE). This review article summarizes the recent advances in the rational design of electrocatalysts with various morphologies and the influence of these morphologies on CO_(2)RR. To compare literature findings in a meaningful way, the article focuses on results reported under a well-defined period and considers the first three rows of the d-block metal catalysts. The discussion typically covers the design of nanostructured catalysts and the molecular-level understanding of morphology-performance relationship in terms of activity, selectivity, and stability during CO_(2) electrolysis. Among others, it would be convenient to recommend a comprehensive discussion on the morphologies of single metals and heterostructures, with a detailed emphasis on their impact on CO_(2) conversion.

关键词： CO_(2)electroreduction Electrochemical reduction of CO_(2) Morphology Catalysts d-block metals catalysts Faradaic efficiency Selectivity

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The effect of altering crosslinker chemistry during interfacial polymerization on the performance of nanofiltration membranes for desalination, organic, and micropollutants removal

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Frontiers of Chemical Science and Engineering 2023年第12期17卷 2025-2036页

作者： Jamilu Usman Abdul Waheed Umair Baig Isam HAljundi interdisciplinary research Centre for membranes and water security King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Chemical Engineering Department King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

Chemistry of the polyamide active layer of a desalination membrane is critical in determining both its physical and chemical *** this study,we designed and fabricated three novel membranes with different active layers using the crosslinkers:terephthaloyl chloride,isophthaloyl chloride,and trimesoyl *** crosslinkers were reacted with an aqueous solution of an aliphatic *** these crosslinkers differ in their structures and crosslinking mechanisms during interfacial polymerization,the resultant membranes also possess different structural *** water contact angle of the fabricated membranes also varies;the water contact angles of 4A-3P-TPC@PSF/PET,4A-3P-TMC@PSF/PET,and 4A-3P-IPC@PSF/PET,are 68.9°,65.6°,and 53.9°,***,the desalination performance of resultant membranes also showed variations,with 4A-3P-TPC@PSF/PET,4A-3P-IPC@PSF/PET,and 4A-3P-TMC@PSF/PET having a permeate flux of 17.14,25.70,and 30.90 L·m^(−2)·h^(−1),respectively,at 2.5 *** 4A-3P-TPC@PSF/PET membrane exhibited extensive crosslinking with aliphatic linear amine,and cationic dye rhodamine B,MgCl_(2),and amitriptyline rejection rates of 98.6%,92.7%and 80.9%,*** 4A-3P-TMC@PSF/PET membrane showed mediocre performance,while 4A-3P-IPC@PSF/PET membrane showed even lower performance,with a 35%rejection of methyl orange dye.

关键词： acid chlorides covalent crosslinking desalination linear aliphatic amine micropollutant removal thin film composite membranes

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Agriculture green development in China: insights and advances

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 5-19,I0005页

作者： Jianbo SHEN Qichao ZHU Yong HOU Wen-Feng CONG Wen XU Jiuliang XU Zhichao AN Xiaoqiang JIAO Kai ZHANG Tianxiang YU Lin MA Oene OENEMA William J.DAVIES Fusuo ZHANG State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China Key Laboratory of Agricultural water Resources Center for Agricultural Resources ResearchInstitute of Genetic and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China Wageningen Environmental research Wageningen University&ResearchWageningen6700 AAthe Netherlands Lancaster Environment Centre University of LancasterLancasterLA14YQUK

Reconciling the tasks of producing adequate amounts of nutritious food for the increasing global population while preserving the environment and natural ecosystems simultaneously is an enormous challenge. The concept of agriculture green development(AGD) and the necessary governmental policies were developed to address the aforementioned challenge in China and to help achieve the related global sustainable development goals. Agriculture green development emphasizes the synergy between green and development;current agriculture has to transform from the intensive farming with high inputs, high environmental impacts and low resource-use efficiency to a more sustainable agriculture, in order to ensure an adequate supply of nutritious food while delivering environmental integrity, improved economic profitability,and social equity. A research program on AGD was established by China Agricultural University with four research themes, namely: green crop production, green integrated crop-animal production, green food and industry,and green ecological environment and ecosystem services, to provide a scientific basis for future developments and to facilitate the implementation of AGD in practice. AGD requires a multistakeholder approach, fueled by innovative and interdisciplinary research. Joint actions have to be taken by governments, farmers, supply industries, consumers, educators, extension services and researchers to support AGD. This requires strong coordination and public awareness campaigns. This review presents the progress that has been made over the past 5 years and makes recommendations for more research and development, in order to better deliver agricultural green and sustainable development on national and international scales.

关键词： Agriculture ecosystem services environmental protection food security green development multi-sectoral cooperation sustainable development

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Multifunctional HDPE/Cu biocidal nanocomposites for MEX additive manufactured parts: Perspectives for the defense industry

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Defence Technology（防务技术） 2024年第8期38卷 16-32页

作者： Nectarios Vidakis Nikolaos Michailidis Markos Petousis Nektarios K.Nasikas Vassilios Saltas Vassilis Papadakis Nikolaos Mountakis Apostolos Argyros Mariza Spiridaki Ioannis Valsamos Department of Mechanical Engineering Hellenic Mediterranean UniversityHeraklion 71410Greece Physical Metallurgy Laboratory Mechanical Engineering DepartmentSchool of EngineeringAristotle University of ThessalonikiThessaloniki 54124Greece Centre for research&Development of Advanced Materials(CERDAM) Center for Interdisciplinary Research and InnovationBalkan CentreThessaloniki 57001Greece Division of Mathematics and Engineering Sciences Department of Military SciencesHellenic Army AcademyVari GR16673AtticaGreece Department of Electronic Engineering Hellenic Mediterranean UniversityChania 73133Greece Department of Industrial Design and Production Engineering University of West AtticaAthens 12244Greece Institute of Electronic Structure and Laser Foundation for Research and TechnologyeHellasHeraklion 70013Greece

In this study, we investigated the performance improvement caused by the addition of copper(Cu)nanoparticles to high-density polyethylene(HDPE) matrix material. Composite materials, with filler percentages of 0.0, 2.0, 4.0, 6.0, 8.0, and 10.0 wt% were synthesized through the material extrusion(MEX)3D printing technique. The synthesized nanocomposite filaments were utilized for the manufacturing of specimens suitable for the experimental procedure that followed. Hence, we were able to systematically investigate their tensile, flexural, impact, and microhardness properties through various mechanical tests that were conducted according to the corresponding standards. Broadband Dielectric Spectroscopy was used to investigate the electrical/dielectric properties of the composites. Moreover, by employing means of Raman spectroscopy and thermogravimetric analysis(TGA) we were also able to further investigate their vibrational, structural, and thermal properties. Concomitantly, means of scanning electron microscopy(SEM), as well as atomic force microscopy(AFM), were used for the examination of the morphological and structural characteristics of the synthesized specimens, while energy-dispersive Xray spectroscopy(EDS) was also performed in order to receive a more detailed picture on the structural characteristics of the various synthesized composites. The corresponding nanomaterials were also assessed for their antibacterial properties regarding Staphylococcus aureus(S. aureus) and Escherichia coli(E. coli) with the assistance of a method named screening agar well diffusion. The results showed that the mechanical properties of HDPE benefited from the utilization of Cu as a filler, as they showed a notable improvement. The specimen of HDPE/Cu 4.0 wt% was the one that presented the highest levels of reinforcement in four out of the seven tested mechanical properties(for example, it exhibited a 36.7%improvement in the flexural strength, compared to the pure matrix). At the same

关键词： High-density polyethylene(HDPE) Copper(Cu) Material extrusion(MEX) Mechanical performance Electrical properties Antibacterial Defense and security

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