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Comparative study on the hydrogen storage performance of as-milled MgRENi rapid quenched alloy catalyzed by metal sulfides

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Journal of Magnesium and Alloys 2024年第5期12卷 2010-2023页

作者： Xiaoping Dong Zhaoqing Zhang Liying Yang Shenghai Xin Dandan Su Zhiyuan Li Department of Mechanical Design and Manufacture and Automation Hebei UniversityBaoding 071000PR China baoding New Energy Vehicle Power Engineering Technology Research Center Hebei UniversityBaoding 071002PR China Hebei Technology Innovation Center for Lightweight of New Energy Vehicle Power System(Preparation) Hebei UniversityBaoding 071002PR China

The composites of Mg_(20)Pr_(1)Sm_(3)Y_(1)Ni_(10)as-quenched alloy and 3 wt.%M(M=CoS,CoS_(2),MoS_(2))catalyst were prepared by high-speed vibration ball *** effects of metal sulfides on the hydrogenation and dehydrogenation dynamics of alloys were *** results show that the as-milled composites contain a large number of amorphous embedded by a small amount of nanocrystals,and there are many point *** ball milling,the crystal grain size in the composites containing CoS is relatively larger,followed by CoS_(2)and MoS_(2)*** hydrogenation,the amorphous phase is crystallized to form Mg_(2)NiH_(4),YH_(3),Pr_(8)H_(18.96),Sm_(3)H_7,Mg,Co or Mo phases,however,Mg_(2)Ni,YH_(2),PrH_(2)and Ni_(3)Y phases appeared after *** maximum hydrogenation capacity of the composites containing CoS,CoS_(2)and MoS_(2)are 3.939,4.265 and 4.507 wt.%,*** hydrogenation saturation ratio of composite containing MoS_(2)is higher than that of the composites containing CoS and CoS_(2).The dehydrogenation activation energy of the composites containing CoS,CoS_(2)and MoS_(2)is 107.76,68.43 and 63.28 ***^(-1).H_(2).On the improvement of hydrogen storage performance of Mg_(20)Pr_(1)Sm_(3)Y_(1)Ni_(10)alloy,the catalytic effect of MoS_(2)sulfide is better than that of CoS_(2)sulfide,and which is better than CoS sulfide.

关键词： Mg_(20)Pr_(1)Sm_(3)Y_(1)Ni_(10)as-quenched alloy CoS CoS_(2)and MoS_(2)sulfide Milling Activation energy Hydrogen storage dynamics

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Predicting carbon storage of mixed broadleaf forests based on the finite mixture model incorporating stand factors,site quality,and aridity index

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Forest Ecosystems 2024年第3期11卷 276-286页

作者： Yanlin Wang Dongzhi Wang Dongyan Zhang Qiang Liu Yongning Li College of Forestry Hebei Agricultural UniversityBaoding071001China College of Economics and Management Hebei Agricultural UniversityBaoding071001China

The diameter distribution function(DDF)is a crucial tool for accurately predicting stand carbon storage(CS).The current key issue,however,is how to construct a high-precision DDF based on stand factors,site quality,and aridity index to predict stand CS in multi-species mixed forests with complex *** study used data from70 survey plots for mixed broadleaf Populus davidiana and Betula platyphylla forests in the Mulan Rangeland State Forest,Hebei Province,China,to construct the DDF based on maximum likelihood estimation and finite mixture model(FMM).Ordinary least squares(OLS),linear seemingly unrelated regression(LSUR),and back propagation neural network(BPNN)were used to investigate the influences of stand factors,site quality,and aridity index on the shape and scale parameters of DDF and predicted stand CS of mixed broadleaf *** results showed that FMM accurately described the stand-level diameter distribution of the mixed *** and *** forests;whereas the Weibull function constructed by MLE was more accurate in describing species-level diameter *** combined variable of quadratic mean diameter(Dq),stand basal area(BA),and site quality improved the accuracy of the shape parameter models of FMM;the combined variable of Dq,BA,and De Martonne aridity index improved the accuracy of the scale parameter *** to OLS and LSUR,the BPNN had higher accuracy in the re-parameterization process of ***,LSUR,and BPNN overestimated the CS of *** but underestimated the CS of *** in the large diameter classes(DBH≥18 cm).BPNN accurately estimated stand-and species-level CS,but it was more suitable for estimating stand-level CS compared to species-level CS,thereby providing a scientific basis for the optimization of stand structure and assessment of carbon sequestration capacity in mixed broadleaf forests.

关键词： Weibull function Finite mixture model Linear seemingly unrelated regression Back propagation neural network Carbon storage

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Local thermal conductivity of inhomogeneous nano-fluidic films:A density functional theory perspective

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Chinese Physics B 2024年第4期33卷 594-603页

作者：孙宗利康艳霜康艳梅 Department of Mathematics and Physics North China Electric Power UniversityBaoding 071003China College of Science Hebei Agricultural UniversityBaoding 071001China Hebei Key Laboratory of Physics and Energy Technology Baoding 071003China university of International Relations Beijing 100091China

Combining the mean field Pozhar-Gubbins(PG)theory and the weighted density approximation,a novel method for local thermal conductivity of inhomogeneous fluids is *** correlation effect that is beyond the mean field treatment is taken into account by the simulation-based empirical *** application of this method to confined argon in slit pore shows that its prediction agrees well with the simulation results,and that it performs better than the original PG theory as well as the local averaged density model(LADM).In its further application to the nano-fluidic films,the influences of fluid parameters and pore parameters on the thermal conductivity are calculated and *** is found that both the local thermal conductivity and the overall thermal conductivity can be significantly modulated by these ***,in the supercritical states,the thermal conductivity of the confined fluid shows positive correlation to the bulk density as well as the ***,when the bulk density is small,the thermal conductivity exhibits a decrease-increase transition as the temperature is *** is also the case in which the temperature is *** fact,the decrease-increase transition in both the small-bulk-density and low-temperature cases arises from the capillary condensation in the ***,smaller pore width and/or stronger adsorption potential can raise the critical temperature for condensation,and then are beneficial to the enhancement of the thermal *** modulation behaviors of the local thermal conductivity lead immediately to the significant difference of the overall thermal conductivity in different phase regions.

关键词： thermal conductivity nano-fluidic films density functional theory

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DCVAE-adv:A Universal Adversarial Example Generation Method for White and Black Box Attacks

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Tsinghua Science and Technology 2024年第2期29卷 430-446页

作者： Lei Xu Junhai Zhai College of Mathematics and Information Science Hebei UniversityBaoding 071002China

Deep neural network(DNN)has strong representation learning ability,but it is vulnerable and easy to be fooled by adversarial *** order to handle the vulnerability of DNN,many methods have been *** general idea of existing methods is to reduce the chance of DNN models being fooled by observing some designed adversarial examples,which are generated by adding perturbations to the original *** this paper,we propose a novel adversarial example generation method,called *** from the existing methods,DCVAE-adv constructs adversarial examples by mixing both explicit and implicit perturbations without using original ***,the proposed method can be applied to both white box and black box *** addition,in the inference stage,the adversarial examples can be generated without loading the original images into memory,which greatly reduces the memory *** compared DCVAE-adv with three most advanced adversarial attack algorithms:FGSM,AdvGAN,and AdvGAN++.The experimental results demonstrate that DCVAE-adv is superior to these state-of-the-art methods in terms of attack success rate and transfer ability for targeted *** code is available at https://***/xzforeverlove/DCVAE-adv.

关键词： deep neural network adversarial examples white box attack black box attack robustness

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Shikimic acid accelerates phase change and flowering in Chinese jujube

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Horticultural Plant Journal 2024年第2期10卷 413-424页

作者： Xianwei Meng Zhiguo Liu Li Dai Weiqiang Zhao Jiurui Wang Lili Wang Yuanpei Cui Ying Li Yinshan Cui Yao Zhang Luyao Wang Fengjiao Yu Jin Zhao Mengjun Liu Research Center of Chinese Jujube Hebei Agricultural UniversityBaodingHebei 071000China College of Horticulture Hebei Agricultural UniversityBaodingHebei 071000China College of Life Science Hebei Agricultural UniversityBaodingHebei 071000China College of Forestry Hebei Agricultural UniversityBaodingHebei 071000China eCollege of Economics and ManagementHebei Agricultural UniversityBaodingHebei 071000China College of Economics and Management Hebei Agricultural University

The juvenile-to-adult phase change with first flowering as the indicator plays a crucial role in the lifecycle of fruit trees. However, the molecular mechanisms underlying phase change in fruit trees remain largely unknown. Shikimic acid (ShA) pathway is a main metabolic pathway closely related to the synthesis of hormones and many important secondary metabolites participating in plant phase change. So,whether ShA regulates phase change in plants is worth clarifying. Here, the distinct morphological characteristics and the underlying mechanisms of phase change in jujube (Ziziphus jujuba Mill.), an important fruit tree native to China with nutritious fruit and outstanding tolerance abiotic stresses, were clarified. A combined transcriptome and metabolome analysis found that ShA is positively involved in jujube(Yuhong’×Xing 16’) phase change. The genes in the upstream of ShA synthesis pathway (ZjDAHPS, ZjDHQS and ZjSDH), the contents of ShA and the downstream secondary metabolites like phenols were significantly upregulated in the phase change period. Further, the treatment of spraying exogenous ShA verified that ShA at a very low concentration (60 mg·L^(-1)) can substantially speed up the phase change and flowering of jujube and other tested plants including Arabidopsis, tomato and wheat. The exogenous ShA (60 mg·L^(-1)) treatment in jujube seedlings could increase the accumulation of endogenous ShA, enhance leaf photosynthesis and the synthesis of phenols especially flavonoids and phenolic acids, and promote the expression of genes (ZjCOs, ZjNFYs and ZjPHYs) involved in flowering pathway. Basing on above results, we put forward a propose for the underlying mechanism of ShA regulating phase change, and a hypothesis that ShA could be considered a phytohormone-like substance because it is endogenous, ubiquitous, movable and highly efficient at very low concentrations. This study highlights the critical role of ShA in plant phase change and its phytohormone-like propert

关键词： Ziziphus jujuba Mill. Phase change Flowering Shikimic acid Transcriptome Metabolome

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Comprehensive understanding of glioblastoma molecular phenotypes:classification,characteristics,and transition

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Cancer Biology & Medicine 2024年第5期21卷 363-381页

作者： Can Xu Pengyu Hou Xiang Li Menglin Xiao Ziqi Zhang Ziru Li Jianglong Xu Guoming Liu Yanli Tan Chuan Fang School of Clinical Medicine Hebei UniversityDepartment of NeurosurgeryAffiliated Hospital of Hebei UniversityBaoding 07100China Hebei Key Laboratory of Precise Diagnosis and Treatment of Glioma Baoding 071000China School of Basic Medical Sciences Hebei UniversityBaoding 07100China Department of Pathology Affiliated Hospital of Hebei UniversityBaoding 07100China

Among central nervous system-associated malignancies,glioblastoma(GBM)is the most common and has the highest mortality *** high heterogeneity of GBM cell types and the complex tumor microenvironment frequently lead to tumor recurrence and sudden relapse in patients treated with *** precision medicine,research on GBM treatment is increasingly focusing on molecular subtyping to precisely characterize the cellular and molecular heterogeneity,as well as the refractory nature of GBM toward *** understanding of the different molecular expression patterns of GBM subtypes is *** have recently proposed tetra fractional or tripartite methods for detecting GBM molecular *** various molecular subtypes of GBM show significant differences in gene expression patterns and biological *** subtypes also exhibit high plasticity in their regulatory pathways,oncogene expression,tumor microenvironment alterations,and differential responses to standard ***,we summarize the current molecular typing scheme of GBM and the major molecular/genetic characteristics of each ***,we review the mesenchymal transition mechanisms of GBM under various regulators.

关键词： Glioblastoma molecular phenotype classification characteristic mesenchymal transition

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Reconfigurable(4, 6^(2)) and(4, 8^(2)) Archimedean plasma photonic crystals in dielectric barrier discharge

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Plasma Science and Technology 2024年第6期26卷 70-78页

作者：李蕊王启晗刘富成高匡雅侯笑含贾萌萌李庆范伟丽 College of Physics Science and Technology Hebei UniversityBaoding 071002People’s Republic of China Institute of Electrostatic Technology Hebei UniversityBaoding 071002People’s Republic of China

Archimedean photonic crystal has become a research area of great interest due to its various unique properties. Here, we experimentally demonstrate the realization of reconfigurable(4, 6^(2))and(4, 8^(2)) Archimedean plasma photonic crystals(APPCs) by use of dielectric barrier discharges in air. Dynamical control on both the macrostructures including the lattice symmetry and the crystal orientation, and the microstructures including the fine structures of scattering elements has been achieved. The formation mechanisms of APPCs are studied by time-resolved measurements together with numerical simulations. Large omnidirectional band gaps of APPCs have been obtained. The tunable topology of APPCs may offer new opportunities for fabricating multi-functional and highly-integrated microwave devices.

关键词： Archimedean lattice plasma photonic crystals dielectric barrier discharge

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Occurrence of dark septate endophytes in Phragmites australis in the Baiyang Lake and their resistance to Cd stress

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Pedosphere 2024年第2期34卷 484-496页

作者： Minghui XU Xia LI Qiannan YE Feng GONG Xueli HE School of Life Sciences Hebei UniversityBaoding 071002China Key Laboratory of Microbial Diversity Research and Application of Hebei Province Hebei UniversityBaoding 071002China

Heavy metal pollution poses a serious hazard to human health,and microbial remediation of heavy metals in soil has been widely studied.A group of ascomycetes classified as dark septate endophytes(DSEs)colonize plant roots and benefit host plants under abiotic stress *** this study,Phragmites australis,a common remediation plant in the Baiyang Lake in North China,was *** and roots of *** were collected in typical heavy metal-contaminated sites,and the species diversity and community structure of DSEs in *** roots were *** addition,DSE strains were isolated,cultured,and tested for their tolerance to Cd *** results showed that DSEs occurred extensively in *** roots,forming typical dark septate hyphae,with a total colonization rate of 19.7%–83.1%.Morphological and internal transcribed spacer sequencing analyses were used to identify 10 species within 9 genera of DSE *** these fungi,6 strains with considerable resistance to Cd stress were *** biomasses of Poaceascoma helicoides,Alternaria doliconidium,and Acrocalymma vagum strains increased as the Cd levels *** results can not only help to understand plant-DSE interactions in wetland environments,but also provide a theoretical basis for making full use of DSE fungi to alleviate heavy metal contamination in soil.

关键词： ascomycete colonization rate contaminated site evenness index heavy metal Shannon-Wiener index Simpson index wetland

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Melatonin and dopamine alleviate waterlogging stress in apples by recruiting beneficial endophytes to enhance physiological resilience

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Journal of Integrative Agriculture 2024年第7期23卷 2270-2291页

作者： Yang Cao Peihua Du Yuwei Shang Jiahao Ji Leiqing Tan Xue Zhang Jizhong Xu Bowen Liang College of Horticulture Hebei Agricultural UniversityBaoding 071001China

Melatonin and dopamine can potentially prevent waterlogging stress in *** current study investigated the mechanism by which melatonin and dopamine alleviate apple waterlogging *** study demonstrated that melatonin and dopamine alleviated waterlogging by removing reactive oxygen species(ROS),and that the nitric oxide(NO)content and nitrate reductase(NR)activity were significantly *** and dopamine were also found to recruit different candidate beneficial endophytes(melatonin:Novosphingobium,Propionivibrio,and Cellvibrio;dopamine:Hydrogenophaga,Simplicispira,Methyloversatilis,Candidatus_Kaiserbacteria,and Humicola),and these endophytes were significantly and positively correlated with plant *** analyses showed that melatonin and dopamine significantly affected the endophytic bacterial and fungal communities under waterlogging *** metabolomic results showed that melatonin and dopamine led to waterlogging resistance by upregulating the abundance of beneficial substances such as amino acids,flavonoids,coumarins,and organic *** addition,melatonin and dopamine regulated the physicochemical properties of the soil,which altered the endophyte community and affected plant *** co-occurrence network demonstrated close and complex relationships among endophytes,metabolites,soil,and the *** results demonstrate that melatonin and dopamine alleviate waterlogging stress in apples by recruiting beneficial endophytes to enhance physiological *** study provides new insights into how melatonin and dopamine alleviate stress and a theoretical basis for synergistic beneficial microbial resistance to waterlogging stress.

关键词： dopamine endophytes Malus hupehensis melatonin metabolomics waterlogging

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A Lightweight, Searchable, and Controllable EMR Sharing Scheme

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Computers, Materials & Continua 2024年第4期79卷 1521-1538页

作者： Xiaohui Yang Peiyin Zhao School of Cyber Security and Computer Hebei UniversityBaoding071000China

Electronic medical records (EMR) facilitate the sharing of medical data, but existing sharing schemes suffer fromprivacy leakage and inefficiency. This article proposes a lightweight, searchable, and controllable EMR sharingscheme, which employs a large attribute domain and a linear secret sharing structure (LSSS), the computationaloverhead of encryption and decryption reaches a lightweight constant level, and supports keyword search andpolicy hiding, which improves the high efficiency of medical data sharing. The dynamic accumulator technologyis utilized to enable data owners to flexibly authorize or revoke the access rights of data visitors to the datato achieve controllability of the data. Meanwhile, the data is re-encrypted by Intel Software Guard Extensions(SGX) technology to realize resistance to offline dictionary guessing attacks. In addition, blockchain technology isutilized to achieve credible accountability for abnormal behaviors in the sharing process. The experiments reflectthe obvious advantages of the scheme in terms of encryption and decryption computation overhead and storageoverhead, and theoretically prove the security and controllability in the sharing process, providing a feasible solutionfor the safe and efficient sharing of EMR.

关键词： Lightweight keyword search large attribute domain controllability blockchain

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