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Incorporating element doping and quantum dot embedding effects to enhance the thermoelectric properties of higher manganese silicides

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Journal of Materiomics 2021年第2期7卷 377-387页

作者： Qing Wang Shiyu Song Xiaofeng Yang Ziyang Liu Yufei Ma Xingyuan San Jianglong Wang Dan Zhang Shu-Fang Wang Zhiliang Li Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province College of Physics Science and TechnologyHebei UniversityBaoding071002China Institute of Life Science and Green Development Hebei UniversityBaoding071002China

Element doping and nano-inclusion embedding are effective approaches to enhance the electrical conductivities and decrease the lattice thermal conductivities of thermoelectric(TE)materials,***,the intrinsic low electrical thermal conductivities and high electrical properties are severely sacrificed,and the final figure of merit(ZT)is usually *** this study,Ag doping and Pt quantum dot(QD)embedding were synchronously achieved via embedding Ag/Pt alloy QDs into the higher manganese silicides to avoid the conventional single-element doping *** power factor(at 823 K)was enhanced from 1.57×10^(-3) W m^(-1) K^(-2) to 1.82×10^(-3) W m^(-1) K^(-2)(-16%)due to the-18%increase in carrier concentration that was derived from the Ag doping ***,the lattice thermal conductivity(at 823 K)decreased from 2.65 W m^(-1) K^(-1) e1.92 W m^(-1) K^(-1)(-28%)because of the broadband phonon scattering effect that resulted from the residual Pt QDs ***,the optimal ZT value increased by-52%from 0.42 to 0.64 at 823 *** study demonstrated that incorporating metastable alloy QDs to obtain element doping and nano-inclusion embedding effects is a novel and feasible means to enhance the ZT value of *** method is also possibly applicable to other alloy QD/TE composites.

关键词： Quantum dot Inclusion Higher manganese silicide Thermoelectric material Figure of merit

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Equilibrium Reinsurance Strategy and Mean Residual Life Function

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 758-777页

作者： Dan-ping LI Lv CHEN Lin-yi QIAN Wei WANG School of Statistics Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOEEast China Normal UniversityShanghai 200062China Academy of Statistics and Interdisciplinary Sciences Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOEEast China Normal UniversityShanghai 200062China School of Mathematics and Statistics Ningbo UniversityNingbo 315211China

In this paper,we analyze the relationship between the equilibrium reinsurance strategy and the tail of the distribution of the *** Mean Residual Life(MRL)has a close relationship with the tail of the distribution,we consider two classes of risk distributions,Decreasing Mean Residual Life(DMRL)and Increasing Mean Residual Life(IMRL)distributions,which can be used to classify light-tailed and heavy-tailed distributions,*** assume that the underlying risk process is modelled by the classical CramérLundberg model *** the mean-variance criterion,by solving the extended Hamilton-Jacobi-Bellman equation,we derive the equilibrium reinsurance strategy for the insurer and the reinsurer under DMRL and IMRL,***,we analyze how to choose the reinsurance premium to make the insurer and the reinsurer agree with the same reinsurance *** find that under the case of DMRL,if the distribution and the risk aversions satisfy certain conditions,the insurer and the reinsurer can adopt a reinsurance premium to agree on a reinsurance strategy,and under the case of IMRL,the insurer and the reinsurer can only agree with each other that the insurer do not purchase the reinsurance.

关键词： mean residual life excess-of-loss reinsurance insurer reinsurer stochastic control

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One-step green synthesis of silica microcapsules with high pesticide loading for sustained-release

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Journal of Environmental Chemical Engineering 2025年第4期13卷

作者： Runhe He Xuetao Tian Zitong Bao Yangyang Chen Qinxin Zhang Hongwei Zhang Yongbing Li Sai Chen Hebei Key Laboratory of Green Development of Rock and Mineral Materials and Institute of Basalt Fiber Materials School of Gemmology and Materials Science Hebei GEO University Shijiazhuang 050031 China Hebei Key Laboratory of Medical-Industrial Integration Precision Medicine School of Clinical Medicine North China University of Science and Technology Tangshan 063000 China Key Laboratory of Carbon Materials of Zhejiang Province Wenzhou University Wenzhou 325035 China Key Laboratory of Development and Application of Rural Renewable Energy Biogas Institute of Ministry of Agriculture and Rural Affairs Chengdu 610041 China

Pesticides are vital for agricultural productivity but their excessive use has raised serious environmental concerns, including soil and water contamination. Traditional pesticide formulations often face issues of rapid degradation, leading to repeated applications and resource waste. Controlled-release systems, particularly microencapsulation, have been proposed as solutions to address these issues, offering the potential to enhance pesticide efficiency and minimize environmental risks. However, traditional methods usually rely on toxic solvents or post-loading processes, which pose significant ecological risks and elevates manufacturing costs. This study presents a one-step green synthesis method to produce silica microcapsules loaded with the pesticide pirimiphos-methyl (PM), a widely used organophosphorus pesticide, without the need for toxic solvents. The synthesis uses tetraethyl orthosilicate (TEOS) and PM as the oil phase, and utilizes surfactants and NaF in an oil/water (O/W) emulsion system. The process is catalyzed by hydrochloric acid to form a silica shell that encapsulates the pesticide in situ. The effects of NaF and the core-to-wall ratio on the morphology, pesticide loading, encapsulation efficiency, thermal stability, and controlled release of the microcapsules were evaluated. The results demonstrate that the microcapsules exhibit high pesticide loading (62.18 %), excellent encapsulation efficiency (up to 92.17 %), and improved thermal stability, with sustained pesticide release over 16 d. This green synthesis method represents a significant advancement in pesticide delivery systems, offering a scalable, eco-friendly solution for sustainable agriculture with reduced environmental and health risks.

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Gaining water bodies by climate change benefits water crisis mitigation in central Asia

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science Bulletin 2025年

作者： Su, Yanan Chen, Shengqian Sui, Yijie Li, Xin Xu, Jinhao Che, Xianghong Xie, Tingting Chen, Jianhui Sheng, Yongwei Feng, Min Chen, Fahu State Key Laboratory of Tibetan Plateau Earth System Environment and Resources Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing100101 China College of Resources and Environment University of Chinese Academy of Sciences Beijing100049 China Research Center of Geospatial Big Data Application Chinese Academy of Surveying and Mapping Beijing100830 China College of Water Resources and Architectural Engineering Tarim University Alar843300 China Key Laboratory of Western China's Environmental Systems Ministry of Education College of Earth and Environmental Sciences Lanzhou University Lanzhou730000 China Department of Geography University of California Los AngelesCA90095 United States Academy of Plateau Science and Sustainability Qinghai Normal University Xining810016 China

Central Asia (CA) faces a severe water crisis exemplified by the shrinking Aral Sea. However, little is known about the entire region, particularly the numerous small water bodies that are vulnerable to climate change yet vital for regional sustainability. We examined water bodies as small as 0.0045 km2 across CA from 1992 to 2020, identifying 66,215 water bodies in 2020, 82.2% of which were previously unstudied. In contrast to the well-documented decline of the Aral Sea, other water bodies have expanded by 10.7% (8714.3 km2), with a net gain of 15,831 lakes since 1992. These findings challenge the perception of a drying CA and provide evidence of a warm-wet climate trend, which is redistributing water resources and creating opportunities for transforming water management to address the long-standing water crisis in CA. © 2025 science China Press

关键词： Central Asia Climate Change Small Water Bodies Water Crisis Water Resource Management

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Attention-based unsupervised prompt learning for SAM in leaf disease segmentation

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Knowledge-Based Systems 2025年 320卷

作者： Tian, Luda Yuan, Yingchun En, Qing Ma, Wei Zhang, Guanghui Liang, Fangfang School of Information Science and Technology Hebei Agricultural University Baoding071001 China Hebei Key Laboratory of Agricultural Big Data Baoding071001 China Hebei Engineering Research Center for Agricultural Remote Sensing Application Baoding071001 China Lab School of Computer Science Carleton University OttawaK1S 5B6 Canada Faculty of Information Technology Beijing University of Technology Beijing100124 China

In modern agriculture, leaf disease segmentation is crucial for crop disease management and yield improvement. Since most deep learning-based segmentation models require extensive annotations, pursuing unsupervised methods becomes a practical solution. Although advanced models like the Segment Anything Model (SAM) can produce precise class-agnostic masks without annotations, their reliance on human-interactive prompts limits their utility to unsupervised disease segmentation tasks. To address this limitation, we present UPLS, a novel three-stage framework that leverages unsupervised prompt learning to enable SAM for leaf disease segmentation. This method employs unsupervised contrastive learning to progressively segment leaf and disease areas and automatically generate disease prompts for SAM. Concretely, for fine and intricate lesions, we utilize an improved high-frequency attention mechanism to extract high-frequency features from the leaf area, and construct contrastive losses between global priors and foreground/background features. Furthermore, we devise a strategy to automatically generate disease-related prompts from the segmented leaf and initial lesion regions, enabling SAM to refine disease boundaries without human intervention. Experiments on three public plant disease segmentation datasets show that UPLS outperforms existing non-fully supervised segmentation methods in accuracy and robustness. Source code is available at https://***/Tianluda/UPLS. © 2025 Elsevier B.V.

关键词： Unsupervised learning

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Remarkable average thermoelectric performance of the highly oriented Bi(Te,Se)-based thin films and devices

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Journal of Materiomics 2024年第2期10卷 366-376页

作者： Zhiliang Li Xiaoqi Yang Zhi Gao Jingxuan Wang Yuli Xue Jianglong Wang Qian Cao Zhihai Ding Shufang Wang Hebei Key Lab of Optic-Electronic Information and Materials Key Laboratory of High-Precision Computation and Application of Quantum Field Theory of Hebei ProvinceCollege of Physics Science and TechnologyHebei UniversityBaoding071002China Huabei Cooling Device Co. LtdXianghe065400China

Bi(Te,Se)-based compounds have attracted lots of attention for nearly two centuries as one of the most successful commercial thermoelectric(TE)materials due to their high performance at near room *** with 3D bulks,2D thin films are more compatible with modern semiconductor technology and have unique advantages in the construction of micro-and *** device applications,high average TE performance over the entire operating temperature range is ***,highly c-axis-oriented N-type Bi(Te,Se)epitaxial thin films have been successfully prepared using the pulsed laser deposition technology by adjusting the deposition *** film deposited at~260℃demonstrate a remarkable average power factor(PFave)of~24.4 mW·cm^(-1)·K^(-2)over the tem-perature range of 305e470 K,higher than most of the state-of-the-art Bi(Te,Se)-based ***,the estimated average zT value of the film is as high as~*** then constructed thin-film TE devices by using the above oriented Bi(Te,Se)films,and the maximum output power density of the device can reach up to~30.1 W/m^(2)under the temperature difference of 40 ***,the outstanding average TE performance of the highly oriented Bi(Te,Se)thin films will have an excellent panorama of applications in semiconductor cooling and power generation.

关键词： Bismuth telluride Oriented thin film Thermoelectric device Average power factor Output power density

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Influence of key Ecological Function Area Policy on the Components of Water Balance-A Case Study in Yangtze River Basin

SSRN

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SSRN 2025年

作者： You, Guangyong Xu, Yan Zhang, Minxia Gao, Yuanyun He, Honglin Zhang, Mengyu Liu, Bo Zhu, Minxin You, Juan Nanjing Institute of Environmental Sciences Ministry of Ecology and Environment Jiangsu Nanjing210042 China Jiangsu Frontier Electric Power Technology Company Limited Jiangsu Nanjing211102 China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing100101 China National Ecosystem Science Data Center Beijing100101 China College of Resources and Environment University of Chinese Academy of Sciences Beijing100190 China School of Remote Sensing and Geomatics Engineering Nanjing University of Information Science and Technology Jiangsu Nanjing210044 China Hebei Engineering Consulting Institute Hebei Shijiazhuang050057 China

The National key Ecological Function Area (KEFA) policy of China, the world's largest ecological compensation program, played an important role in improving the ecological functions. To reveal the effects of KEFA on land surface water balance components, this study analyzed the difference between KEFA area and the rest of the area (NKEF) in Yangtze River Basin (YRB). The results showed that, 1) the KEFA had higher interception loss (Ei) but lower actual evaporation (Ea) and transpiration (Et) than NKEF. The proportions of Ea, Et, Ei to precipitation (Pre) were higher in KEFA than NKEF, suggesting the KEFA had higher water consumption possibly resulting from the vegetation growth and dynamics. 2) Over the past decades, Ea, Et, and Ei, as well as their proportions to Precipitation (PRE), were significantly increased in YRB. A significant change point around the year 2000 coincided with the climate cycles periods and implementations of national ecological restoration programs i.e. National Grain for Green Program. 3) The long-term trends of Ea/Pre and the Ei/Pre were higher in KEFA than NKEF, especially for the post-2000 period. Compared with pre-2000 period, The Ea/Pre, Et/Pre of the NKEF in the post-2000 period displayed sharp decrease, suggesting the decreasing vegetation cover and water consumption. This study revealed the hydrological effects of KEFA policy, the findings are meaningful in evaluating and optimizing the KEFA policy. © 2025, The Authors. All rights reserved.

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Using Hourly Measurements to Explore the Role of Secondary Inorganic Aerosol in PM_(2.5)during Haze and Fog in Hangzhou, China

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Advances in Atmospheric sciences 2014年第6期31卷 1427-1434页

作者： Roeland Cornelis JANSEN SHI Yang CHEN Jianmin HU YunJie XU Chang HONG Shengmao LI Jiao ZHANG Min Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science & Engineering Fudan University Hangzhou Municipal Environmental Monitoring Center Key Laboratory of Data Analysis and Application the First Institute of OceanographyState Oceanic Administration

This paper explores the role of the secondary inorganic aerosol （SIA） species ammonium,NH4＋,nitrate,NO3-,and sulfate,SO24-,during haze and fog events using hourly mass concentrations of PM2.5 measured at a suburban site in Hangzhou,China.A total of 546 samples were collected between 1 April and 8 May *** samples were analyzed and classified as clear,haze or fog depending on visibility and relative humidity （RH）.The contribution of SIA species to PM2.5 mass increased to ～50％ during haze and *** mass contribution of nitrate to PM2.5 increased from 11％ during clear to 20％ during haze *** mass exceeded sulfate mass during haze,while near equal concentrations were observed during fog *** role of RH on the correlation between concentrations of SIA and visibility was examined,with optimal correlation at 60％-70％ *** total acidity during clear,haze and fog periods was 42.38,48.38 and 45.51 nmol m-3,respectively,indicating that sulfate,nitrate and chloride were not neutralized by ammonium during any *** nitrate to sulfate molar ratio,as a function of the ammonium to sulfate molar ratio,indicated that nitrate formation during fog started at a higher ammonium to sulfate molar ratio compared to clear and haze *** haze and fog,the nitrate oxidation ratio increased by a factor of 1.6-1.7,while the sulfur oxidation ratio increased by a factor of 1.2-1.5,indicating that both gaseous NO2 and SO2 were involved in the reduced visibility.

关键词： haze secondary inorganic aerosol PM2.5 Yangtze River Delta

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Energy storage performance and phase transition under high electric field in Na/Ta co-doped AgNbO_(3)ceramics

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Journal of Materiomics 2023年第1期9卷 19-26页

作者： Mingyuan Zhao Jing Wang Hao Yuan Zehan Zheng Lei Zhao Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province College Physics Science and TechnologyHebei UniversityBaoding071002China State Key Laboratory of Mechanics and Control of Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing210016China

Lead-free antiferroelectric ceramics with high energy storage performance show great potential in pulsed power ***,poor breakdown strength and antiferroelectric stability are the two main drawbacks that limit the energy storage performance of antiferroelectric ***,highquality(Ag_(1-x)Na_(x))(Nb_(1-x)Ta_(x))O_(3)ceramics were prepared by the tape casting *** breakdown strength was greatly improved as a result of the high density and fine grains,while the antiferroelectric stability was enhanced owning to the M2 *** from the synergistic improvement in breakdown strength and antiferroelectric stability,(Ag_(0.80)Na_(0.20))(Nb_(0.80)Ta_(0.20))O_(3)ceramic reveals a benign energy storage performance of W_(rec)=5.8 J/cm^(3)and h=61.7%with good temperature stability,frequency stability and cycling *** is also found that the high applied electric field can promote the M2-M3 phase transition,which may provide ideas to improve the thermal stability of the energy storage performance in AgNbO_(3)-based ceramics.

关键词： Antiferroelectric ceramics AgNbO_(3)-based ceramics Phase transition Tape casting process

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Horizon thermodynamics in f(R,R^μνRμν)theory

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Chinese Physics C 2020年第11期44卷 208-212页

作者： Haiyuan Feng Rong-Jia Yang College of Physical Science and Technology Hebei UniversityBaoding 071002China Hebei Key Lab of Optic-Electronic Information and Materials Hebei UniversityBaoding 071002China National-Local Joint Engineering Laboratory of New Energy Photoelectric Devices Hebei UniversityBaoding 071002China Key Laboratory of High-pricision Computation and Application of Quantum Field Theory of Hebei Province Hebei UniversityBaoding 071002China

We investigate whether the new horizon first law still holds in f(R,R^μνRμν)*** this complicated theory,we first determine the entropy of a black hole by using the Wald method,and then derive the energy of the black hole by using the new horizon first law,the degenerate Legendre transformation,and the gravitational field *** application,we consider the quadratic-curvature gravity,and first calculate the entropy and energy of a static spherically symmetric black hole,which are in agreement with the results obtained in the literature for a Schwarzschild-(A)dS black hole.

关键词： black hole energy entropy new horizon first law

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