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Optimizing Solar Energy Harvesting: A K-Means Clustering Approach for Enhanced Efficiency and Viability

ENERGY SCIENCE & ENGINEERING 2025年第1期13卷 191-202页

作者： Bin, Li Shahzad, Muhammad Farhan, Muhammad Khan, Muhammad Sanaullah Saif, Mubaarak Abdulrahman Abdu Bitew, Girmaw Teshager North China Elect Power Univ Sch Elect & Elect Engn Beijing Peoples R China Muhammad Nawaz Sharif Univ Engn & Technol Dept Elect Engn Multan Pakistan Govt Coll Univ Faisalabad Dept Elect Engn & Technol Faisalabad Pakistan Taiz Univ Fac Engn & Informat Technol Renewable Energy Dept Taizi Yemen Bahir Dar Univ Bahir Dar Inst Technol Fac Elect & Comp Engn Bahir Dar Ethiopia

In recent years, photovoltaic (PV) solar energy has played a crucial role in the global transition toward renewable energy, contributing to 46% of the electric capacity. It has emerged as a primary source;however, optimizing energy utilization and solar panel efficiency to maximize absorbed solar radiation remains a significant challenge. Additionally, it addresses the optimization of solar energy generation and the mitigation of potential overheating issues in dual-axis solar tracking systems. Despite its importance, PV power generation is hindered by uncertainty and intermittency, posing obstacles to achieving a stable and reliable power supply. This research introduces an innovative synthesis method for a typical solar radiation year (TSRY) based on K-means clustering to maximize energy harvest. The K-means algorithm, a fundamental image processing technique, is utilized to classify images into distinct groups. This approach enhances energy generation potential, panel efficiency, and the long-term sustainability of solar energy systems compared to conventional methods.

关键词： distributed generation K-means clustering maximum power point tracking photovoltic energy renewable energy sustainable energy

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Multi-mechanism REYs enrichment in early Cambrian phosphorites within inner-shelf:Constraints from the geochemistry characteristics of francolite in Kunyang,Yangtze Block

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Geoscience Frontiers 2025年第2期16卷 263-281页

作者： Pei Liang Junyi Wang Li Chen Yuling Xie Bingbing Zhao School of Civil and Resources Engineering University of Science and Technology BeijingNo.30 Xueyuan RoadHaidian DistrictBeijing 100083China Yunnan Hong Fu Chemical Co.Ltd. Kunming 654100China

Middle and heavy rare earth elements and yttrium (MHREYs) are critical to the high-tech and green-energy industries, generating tremendous supply risk in recent decades. Recently, sedimentary phosphorites have been identified as a new resource for MHREYs. The Early Cambrian is considered one of the critical large-scale phosphorus-forming periods in china and globally. During this period, widespread large-scale phosphorites mainly occurred at shelf, while small-scale phosphate concretions predominantly existed in near-slope settings on the Yangtze Block, South china. However, multi controls for ore-forming mechanism of extraordinary REYs enrichment in phosphorites have not been well constrained, limiting the understanding of the formation of large-scale phosphorites at shelf. To better understand the REYs enrichment in phosphorite, the REYs-rich Kunyang phosphorite, the largest phosphorite in shelf environment on the Yangtze Block, was investigated through mineralogy, in-situ geochemistry of major and trace elements in francolites. Based on the mineral characteristics, four types of phosphorite and four types of wall rocks were divided, which can be grouped into high-REYs (435–717 ppm) and low-REYs (224–282 ppm) categories. Comparing the geochemical characteristics of high-REYs and low-REYs groups, multi-mechanisms of REYs enrichment can be supposed. Frequent Fe redox cycling and related suboxic conditions may be responsible for the extraordinary REYs enrichment in phosphorites. In high-energy hydrodynamic systems with a low sedimentation rate, prolonged deposition of francolite enhanced the effects of adsorption and substitution in the early and late diagenetic stages, respectively, significantly increasing REYs uptake. Moreover, in the inner-shelf environment, wave fluctuations and storm effects are significant, leading to extensive diagenetic reworking, which form extremely high REYs contents in the altered rims of francolite. The negative Eu anomalies in the high

关键词： Kunyang REYs Phosphorite Early Cambrian In-situ geochemistry

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Adjoint-based RCS surface sensitivity calculation for very large electrical size object

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Defence Technology(防务技术) 2025年第5期47卷 164-179页

作者： Jun Deng Zhenghong Gao Lin Zhou Ke Zhao Jiangtao Huang Wei Zhang Northwestern Polytechnical University Xi'an 710072China National Key Laboratory of Aircraft Configuration Design Xi'an 710072China China Aerodynamic Research and Development Center Mianyang 621000China

The primary concern in stealth aircraft design is the very large electrical size ***,the computational and storage requirements of these objects present significant obstacles for current highfidelity design methods,particularly when addressing high-dimensional complex engineering design *** address these challenges,we developed a surface sensitivity technique based on the multilevel fast multipole algorithm(MLFMA).An access and storage of sparse partial derivative tensor was improved to significantly enhanced the computation *** far-field interactions of the surface sensitivity equation were realized by differential the multipole *** addition,we proposed a fast far-field multiplication method to accelerate the multiplication *** surface mesh derivative with respect to the design variables was calculated by analytical and complex variable methods,substantially improving computational *** advancements enabled the MLFMAbased surface sensitivity method to millions meshes and large-scale gradients,extending gradientbased optimization for very large electrical size *** cases have verified the effectiveness of this method in optimizing very large electrical objects in terms of both accuracy and efficiency.

关键词： Surface sensitivity Gradient MLFMA Discrete adjoint Very large electrical size RCS

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Internal response of vegetation growth to degrees of permafrost degradation in Northeast china from 2001 to 2020

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地球空间信息科学学报（英文版） 2025年第1期28卷中插15,265-283页

作者： Hong Yang Yanqiu Xing Xiaoqing Chang Jiaqi Wang Yuanxin Li Jie Tang Dejun Wang Centre for Forest Operations and Environment College of Mechanical and Electrical EngineeringNortheast Forestry UniversityHarbinChina College of Public Administration and Law Northeast Agricultural UniversityHarbinChina

Ecosystems at the southern edge of the permafrost distribution are highly sensitive to global *** in soil freeze-thaw cycles can influence vegetation growth in permafrost *** studies mainly focused on analyzing the differences of vegetation dynamics in different permafrost ***,the intrinsic drivers of permafrost degradation on vegetation growth remain elusive *** on the top temperature of permafrost(TTOP)model,we simulated the spatial distribution of permafrost in Northeast china(NEC)from 2001 to *** the data of the vegetation Net Primary Productivity(NPP),vegetation phenology,climate and permafrost phenol-ogy,and analytical methods including partial correlation,multiple linear regression,and path analysis,we explored the response of vegetation growth and phenology to soil freeze-thaw changes and climate change under different degrees of permafrost ***,the start date of the growing season(SOS)was very sensitive to the start date of soil thaw(SOT)changes,and multiple regression analyses showed that SOT was the main factor influencing SOS in 41.8%of the NEC *** factors remain the main factors affecting vegetation NPP in NEC,and the results of partial correlation analysis showed that only 9.7%of the regional duration of soil thaw(DOT)had a strong correlation with vegetation ***,we determined the mechan-ism responsible for the soil freeze-thaw changes and vegetation growth relationship using the path *** results indicated that there is a potential inhibitory effect of persistent permafrost degradation on vegetation *** findings would contribute to the improvement of process-based models of forest dynamics in the boreal region,which would help to plan sustainable development and conservation strategies in permafrost areas.

关键词： Permafrost degradation vegetation growth Net Primary Productivity(NPP) Northeast china(NEC) internal response

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Systematic metabolic engineering enables highly efficient production of vitamin A in Saccharomyces cerevisiae

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Synthetic and Systems Biotechnology 2025年第1期10卷 58-67页

作者： Yi Shi Shuhuan Lu Xiao Zhou Xinhui Wang Chenglong Zhang Nan Wu Tianyu Dong Shilong Xing Ying Wang Wenhai Xiao Mingdong Yao Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China Frontier Research Institute for Synthetic Biology Tianjin UniversityChina CABIO Bioengineering(Wuhan)Co. LtdWuhan430075China School of Life Sciences Faculty of MedicineTianjin UniversityChina Georgia Tech Shenzhen Institute Tianjin UniversityShenzhen518071China

Vitamin A is a micronutrient critical for versatile biological functions and has been widely used in the food,cosmetics,pharmaceutical,and nutraceutical *** biology and metabolic engineering enable microbes,especially the model organism Saccharomyces cerevisiae(generally recognised as safe)to possess great potential for the production of vitamin ***,we first generated a vitamin A-producing strain by miningβ-carotene 15,15′-mono(di)oxygenase from different sources and identified two isoenzymes Mbblh and Ssbco with comparable catalytic properties but different catalytic *** expression of isoenzymes increased the flux fromβ-carotene to vitamin A *** modulate the vitamin A components,retinol dehydrogenase 12 from Homo sapiens was introduced to achieve more than 90%retinol purity using shake flask *** POS5Δ17 enhanced the reduced nicotinamide adenine dinucleotide phosphate pool,and the titer of vitamin A was elevated by almost 46%.Multi-copy integration of the key rate-limiting step gene Mbblh further improved the synthesis of vitamin ***,the titer of vitamin A in the strain harbouring the Ura3 marker was increased to 588 mg/L at the shake-flask ***,the highest reported titer of 5.21 g/L vitamin A in *** was achieved in a 1-L *** study unlocked the potential of *** for synthesising vitamin A in a sustainable and economical way,laying the foundation for the commercial-scale production of bio-based vitamin A.

关键词： Vitamin A Isozyme Retinol Metabolic engineering Cofactor engineering Saccharomyces cerevisiae

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Strain rate dependence of dynamic recrystallization and texture evolution in hot compressed Mg-Gd-Er-Zr alloy

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Journal of Magnesium and Alloys 2025年第1期13卷 161-171页

作者： Ning Ding Wenbo Du Shubo Li Ke Liu Xian Du Zijian Yu Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China

Hot deformation with high strain rate has been paid more attention due to its high efficiency and low cost,however,the strain rate dependent dynamic recrystallization(DRX)and texture evolution in hot deformation process,which affect the formability of metals,are lack of *** this work,the DRX behavior and texture evolution of Mg-8Gd-1Er-0.5Zr alloy hot compressed with strain rates of 0.1 s^(−1),1 s^(−1),10 s^(−1) and 50 s^(−1) are studied,and the corresponding dominant mechanisms for DRX and texture weakening are *** indicated the DRX fraction was 20%and the whole texture intensity was 16.89 MRD when the strain rate was 0.1 s^(−1),but they were 76%and 6.55 MRD,respectively,when the strain rate increased to 50 s^(−1).The increment of DRX fraction is suggested to result from the reduced DRX critical strain and the increased dislocation density as well as velocity,while the weakened whole texture is attributed to the increased DRX *** the low strain rate of 0.1 s^(−1),discontinuous DRX(DDRX)was the dominant,but the whole texture was controlled by the deformed grains with the preferred orientation of{0001}⊥CD,because the number of DDRX grains was *** the high strain rate of 50 s^(−1),continuous DRX(CDRX)and twin-induced DRX(TDRX)were promoted,and more DRX grains resulted in orientation *** whole texture was mainly weakened by CDRX and TDRX grains,in which CDRX plays a major *** results of present work are significant for understanding the hot workability of Mg-RE alloys with a high strain rate.

关键词： Dynamic recrystallization Texture Hot compression Strain rate Mg-Gd-Er-Zr alloy

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Dual-phase synergistically enhancing mechanical properties and thermal conductivity of hot-extruded Mg-8Gd-1Er-8Zn-1Mn alloy

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Journal of Magnesium and Alloys 2025年第3期13卷 1176-1186页

作者： Xudong Li Wenbo Du Feng Lou Ning Ding Xian Du Shubo Li College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China

The contradiction between mechanical properties and thermal conductivity of magnesium alloys is a roadblock for their widespread *** this study,we developed a hot-extruded Mg-8Gd-1Er-8Zn-1Mn alloy with high-strength and high-thermal-conductivity via dual-phase,W-phase andα-Mn,synergistically *** alloy extruded at 300℃ exhibited the yield strength and elongation of 372 MPa and 12%,respectively,it simultaneously demonstrated a high thermal conductivity of 134.3W/(m·K).After extrusion,the original coarse W-phase in the alloy was broken into near-spheroidal particles,which reduced the probability of electron *** addition,a large number of solute atoms dynamically precipitated in the form of nanoscale rod-like W-phase andα-Mn,makingα-Mg matrix revert to a nearly periodic arrangement *** high yield strength of the alloy is predominantly determined by grain boundary strengthening as well as W-phase andα-Mn dual-phase ***,the strategy of dual-phase strengthening provides a valuable approach for developing structure-function integrated Mg alloys.

关键词： Mg-RE-Zn alloy W-phase α-Mn Thermal conductivity Strength

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Texture,residual stress and mechanical properties of 7039-T6 thick plate Al alloy with MIG-welded laminar tearing

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International Journal of Minerals,Metallurgy and Materials 2025年第5期32卷 1176-1189页

作者： Jinghan Yang Linyang Wu Yong Lian Rongjun Zhang Xingyu Chen Jin Zhang Pengfei Ji Jinshan Luo Fangyun Chen Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Corrosion Erosion and Surface TechnologyUniversity of Science and Technology BeijingBeijing 100083China Institute of Engineering Technology University of Science and Technology BeijingBeijing 100083China Chongqing Changan Wangjiang Industry Group Co.Ltd. Chongqing 400054China

7039 Al alloys are widely used in armor vehicles,given the material’s high specific strength and fracture ***,laminar tearing in the thickness plane of the base metal(BM),specifically in the normal direction(ND)and rolling direction(RD)plane,was occasionally observed after the welding of thick plates,resulting in premature material failure.A vertically metal-inert gas(MIG)-welded laminar tearing component of a 30 mm thick plate was analyzed to determine the factors associated with this *** texture,residual stress,microhardness,and tensile properties were also *** results indicated that the crack extended along the RD as a transcrystalline fracture and terminated at the *** grains near the crack grew preferentially in the(001)crystal ***,the tensile strength(83 MPa)and elongation(6.8%)in the RD were relatively higher than those in the *** particular,the primary factors for crack initiation include stronger texture,higher dislocation density,increased Al_(7)Cu_(2)Fe phases,lower proportion of small-angle grain boundaries,and varying grain sizes in different regions,leading to the fragile *** higher residual stress of the BM promotes the formation and extension of *** restraining force due to fixation and welding shrinkage force transformed the crack into laminar *** measures of laminar tearing were also proposed.

关键词： metal-inert gas welded Al alloy thick plate laminar tearing texture residual stress mechanical properties

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Recent progress on non-metallic carbon nitride for the photosynthesis of H_(2)O_(2):Mechanism,modification and in-situ applications

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Chinese Chemical Letters 2025年第1期36卷 165-175页

作者： Hao Lv Zhi Li Peng Yin Ping Wan Mingshan Zhu College of Environment and Climate Jinan UniversityGuangzhou 511443China Jiading Branch of Shanghai General Hospital Shanghai Jiao Tong University School of MedicineShanghai 201803China Department of Liver Surgery Ren Ji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China

Photocatalytic hydrogen peroxide(H_(2)O_(2))production has been considered as a promising strategy for H_(2)O_(2)synthesis due to its environmentally *** various photocatalysts,carbon nitride-based materials are excellent candidates for H_(2)O_(2)production because of their excellent visible-light response,low cost and high *** this review,we summarize in detail the research progress on the photocatalytic production of H_(2)O_(2)by carbon ***,we summarize the basic principles of photocatalysis and photocatalytic H_(2)O_(2)***,the classification and modification methods of carbonnitride-based materials are discussed,including morphology modulation,noble metal loading,defect control,heterojunction regulation,molecular structure engineering and elemental ***,the different in-situ applications of H_(2)O_(2)via photosynthesis were discussed,including disinfection and antibiotic resistant genes degradation,organic pollutants degradation,medical applications and fine chemical *** review brings great promise for in-situ H_(2)O_(2)photosynthesis,which is expected to serve as a key component in future applications.

关键词： Carbon nitride Hydrogen peroxide Photocatalysis Applications

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ZmHB53, a Maize Homeodomain-Leucine Zipper I Transcription Factor Family Gene, Contributes to Abscisic Acid Sensitivity and Confers Seedling Drought Tolerance by Promoting the Activity of ZmPYL4

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PLANT CELL AND ENVIRONMENT 2025年第6期48卷 3829-3843页

作者： Zhong, Yuan Yan, Xiaocui Wang, Nan Zenda, Tinashe Dong, Anyi Zhai, Xiuzhen Yang, Qian Duan, Huijun Hebei Agr Univ Coll Agron State Key Lab North China Crop Improvement & Regul Minist EducKey Lab Crop Germplasm Resources North Baoding Hebei Peoples R China

Plant-specific homeodomain-leucine zipper I (HD-Zip I) transcription factors (TFs) crucially regulate plant drought tolerance. However, their specific roles in maize (Zea mays L.) regulating drought tolerance remain largely unreported. Here, we screened a maize HD-Zip I TF family gene, ZmHB53, and clarified its role in drought stress. ZmHB53 overexpression maize plants exhibited sensitivity to abscisic acid (ABA), tolerant to polyethylene glycol (PEG 6000)-induced stress during germination, along with improved seedling drought resistance. Compared to the wild-type, ZmHB53 overexpression lines show higher water retention, biomass, and survival rates, and reduced water loss and stomatal size under drought, suggesting ZmHB53 ' s role in drought adaptation. DNA affinity purification sequencing (DAP-Seq), yeast one hybrid, electrophoretic mobility shift assay (EMSA), and dual luciferase showed that ZmHB53 directly bound to and upregulated the expression of ABA receptor ZmPYL4. Meanwhile, transgenic plants overexpressing ZmPYL4 also exhibit ABA sensitivity and drought tolerance. The research results provide novel insights into the regulatory role of ZmHB53 and ZmPYL4 in enhancing maize's drought tolerance, establishing a foundation for future validation and potential application of ZmHB53 in strategies to improve maize resistance to drought.

关键词： drought stress HD-Zip I transcription factors maize PYL ABA receptors root elongation stomatal closure

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