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Microstructure and room temperature fracture toughness of Nb-Si-based alloys with Sr addition

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Rare Metals 2024年第8期43卷 3904-3912页

作者： Yong-Lin Huang Li-na Jia Bin Kong Yue-Ling Guo na wang School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Nb-Si-based alloys show great potential to surpass the widely used Ni-based *** element Sr is widely applied in aluminum and magnesium alloys,but reports about the effects of Sr on Nb-Si-based alloys are quite ***,Nb-Si-based alloys with nominal compositions of Nb-15Si-24Ti-4Cr-2Al-2Hf-0/0.05/0.15Sr(at%)were prepared by directional solidification and heat *** microstructural characterization and room temperature fracture toughness of Nb-Si-based alloy were systematically *** show that all these alloys consist of Nb_5Si_3 phase embedded within Nb solid solution(Nb_(ss)) *** Nb_(5)Si_(3) phase becomes refined and more discontinuous after adding minor *** for the fracture toughness,0.05 at% and 0.15 at% Sr additions do not cause significant *** discontinuous and refining mechanism of Sr element was studied,and the analysis of toughness decreasing with Sr addition reveals that the size of Nb_(ss) phase plays a crucial role in determining the fracture toughness.

关键词： Nb-Si alloy Refinement Discontinuous Fracture toughness Nb_(ss)

Big Data Access Control Mechanism Based on Two-Layer Permission Decision Structure

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Computers, Materials & Continua 2024年第4期79卷 1705-1726页

作者： Aodi Liu na wang Xuehui Du Dibin Shan Xiangyu Wu Wenjuan wang He’nan Province Key Laboratory of Information Security Information Engineering UniversityZhengzhou450000China

Big data resources are characterized by large scale, wide sources, and strong dynamics. Existing access controlmechanisms based on manual policy formulation by security experts suffer from drawbacks such as low policymanagement efficiency and difficulty in accurately describing the access control policy. To overcome theseproblems, this paper proposes a big data access control mechanism based on a two-layer permission decisionstructure. This mechanism extends the attribute-based access control (ABAC) model. Business attributes areintroduced in the ABAC model as business constraints between entities. The proposed mechanism implementsa two-layer permission decision structure composed of the inherent attributes of access control entities and thebusiness attributes, which constitute the general permission decision algorithm based on logical calculation andthe business permission decision algorithm based on a bi-directional long short-term memory (BiLSTM) neuralnetwork, respectively. The general permission decision algorithm is used to implement accurate policy decisions,while the business permission decision algorithm implements fuzzy decisions based on the business *** BiLSTM neural network is used to calculate the similarity of the business attributes to realize intelligent,adaptive, and efficient access control permission decisions. Through the two-layer permission decision structure,the complex and diverse big data access control management requirements can be satisfied by considering thesecurity and availability of resources. Experimental results show that the proposed mechanism is effective andreliable. In summary, it can efficiently support the secure sharing of big data resources.

关键词： Big data access control data security BiLSTM

The Influence of Different Solar System Planetary Ephemerides on Pulsar Timing

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Research in Astronomy and Astrophysics 2024年第8期24卷 85-99页

作者： Jian-Peng Dai Wei Han na wang School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China

Pulsar timing offers a comprehensive avenue for exploring diverse topics in physics and *** solar system planetary ephemeris is crucial for pulsar timing as it provides the positions and velocities of solar system planets including the ***,it is inevitable that inherent inconsistencies exist in these *** between various ephemerides can significantly impact pulsar timing and parameter ***,pulsar timing highly depends on the JPL DE ephemeris,for instance,the Pulsar Timing Array data analysis predominantly utilizes *** this study,we examine inconsistencies across various ephemeris series,including JPL DE,EPM,and ***,discrepancies emerge particularly between the current ephemeris DE436 and the earliest released ephemeris DE200,as well as the most recent ephemerides,e.g.,DE440,INPOP21A,and *** detailed analysis of the effects of ephemeris on geometric correction procedures for the conversion of measured topocentric times of arrival is presented in this *** researches reveal that variations in the Roemer delays across different ephemerides lead to distinct *** timing residuals and the fact that these discrepancies can be readily incorporated into the subsequent pulsar parameters,leading to inconsistent fitting estimates,suggest that the influence of errors in the ephemeris on the timing process might currently be underappreciated.

关键词： (stars)pulsars general-Planetary Systems-time-ephemerides

CRBFT:A Byzantine Fault-Tolerant Consensus Protocol Based on Collaborative Filtering Recommendation for Blockchains

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Computers, Materials & Continua 2024年第7期80卷 1491-1519页

作者： Xiangyu Wu Xuehui Du Qiantao Yang Aodi Liu na wang Wenjuan wang He’nan Province Key Laboratory of Information Security Information Engineering UniversityZhengzhou450000China School of Cyber Science Engineering Zhengzhou UniversityZhengzhou450000China

Blockchain has been widely used in finance,the Internet of Things(IoT),supply chains,and other scenarios as a revolutionary *** protocol plays a vital role in blockchain,which helps all participants to maintain the storage state ***,with the improvement of network environment complexity and system scale,blockchain development is limited by the performance,security,and scalability of the consensus *** address this problem,this paper introduces the collaborative filtering mechanism commonly used in the recommendation system into the Practical Byzantine Fault Tolerance(PBFT)and proposes a Byzantine fault-tolerant(BFT)consensus protocol based on collaborative filtering recommendation(CRBFT).Specifically,an improved collaborative filtering recommendation method is designed to use the similarity between a node’s recommendation opinions and those of the recommender as a basis for determining whether to adopt the recommendation *** can amplify the recommendation voice of good nodes,weaken the impact of cunningmalicious nodes on the trust value calculation,andmake the calculated resultsmore *** addition,the nodes are given voting power according to their trust value,and a weight randomelection algorithm is designed and implemented to reduce the risk of *** experimental results show that CRBFT can effectively eliminate various malicious nodes and improve the performance of blockchain systems in complex network environments,and the feasibility of CRBFT is also proven by theoretical analysis.

关键词： Blockchain consensus byzantine fault-tolerant collaborative filtering trust

The Adjustment Analysis Method of the Active Surface Antenna Based on Convolutional Neural Network

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Research in Astronomy and Astrophysics 2024年第6期24卷 294-306页

作者： You Ban Shang Shi na wang Qian Xu Shufei Feng School of Mechanical Engineering Xinjiang UniversityUrumqi 830017China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China

Active surface technique is one of the key technologies to ensure the reflector accuracy of the millimeter/submillimeter wave large reflector *** antenna is complex,large-scale,and high-precision equipment,and its active surfaces are affected by various factors that are difficult to comprehensively deal *** this paper,based on the advantage of the deep learning method that can be improved through data learning,we propose the active adjustment value analysis method of large reflector antenna based on deep *** method constructs a neural network model for antenna active adjustment analysis in view of the fact that a large reflector antenna consists of multiple panels spliced *** on the constraint that a single actuator has to support multiple panels(usually 4),an autonomously learned neural network emphasis layer module is designed to enhance the adaptability of the active adjustment neural network *** classical 8-meter antenna is used as a case study,the actuators have a mean adjustment error of 0.00252 mm,and the corresponding antenna surface error is0.00523 *** active adjustment result shows the effectiveness of the method in this paper.

关键词： techniques:radar astronomy telescopes methods:analytical methods:numerical

Transverse mode-coupling instability with longitudinal impedance

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Nuclear Science and Techniques 2024年第6期35卷 40-53页

作者： Hai-Sheng Xu Chun-Tao Lin na wang Jing-Ye Xu Yuan Zhang Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Institute of Advanced Science Facilities Shenzhen 518107GuangdongChina

Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle *** mechanism of TMCI can be explained by the coupling of transverse coherent oscillation modes owing to the transverse short-range wakefield(i.e.,the transverse broadband impedance).Recent studies on future circular colliders,e.g.,FCC-ee,showed that the threshold of TMCI decreased significantly when both longitudinal and transverse impedances were *** performed computations for the circular electron-positron collider(CEPC)and observed a similar *** studies on the influence of longitudinal impedance on the TMCI threshold were *** concluded that the imaginary part of the longitudinal impedance,which caused a reduction in the incoherent synchrotron tune,was the primary reason for the reduction in the TMCI ***,the real part of the longitudinal impedance assists in increasing the TMCI threshold.

关键词： Transverse mode-coupling instability Longitudinal impedance

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Electrolytes additives for Zn metal anodes: regulation mechanism and current perspectives

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Rare Metals 2024年第9期43卷 4162-4197页

作者： Yu-Zhe Zhang Huai-Sheng Ao Qi Dong Shao-Jie Zhang Zhi-Guo Hou na-na wang Xue-Song Xie Jian Rong Zhong-Yu Li School of Environmental Science and Engineering Changzhou University School of Petrochemical Engineering Changzhou University Hefei national Laboratory for Physical Science at Microscale School of Chemistry and Materials Science University of Science and Technology of China Institute for Superconducting and Electronic Materials Australian Institute for Innovative Materials Innovation Campus University of Wollongong Department of Chemical and Materials Engineering University of Alberta

With distinct advantages such as high gravimetric and volumetric capacity(5855 mAh·cm-3and 820mAh·g-1), low redox potential(-0.762 V vs. standard hydrogen electrode（SHE）), high abundance, low toxicity and intrinsic safety of Zn metal anode, Zn-ion batteries have become a potential alternative to Li-ion ***, several challenges still need to be addressed prior to the practical applications of Zn-ion batteries, such as dendrite growth during Zn plating/stripping and interfacial side reactions on the Zn surface. Such issues can be addressed by introducing additives to regulate the components and structures of the electrolyte. In this review, we systematically discussed the core issues of metallic Zn anodes and comprehensively summarized a novel perspective of the regulation mechanism of inhibiting dendrite growth or interfacial side reactions in Zn anodes by introducing additives into aqueous ***, some discussions and prospects for aqueous Zn ion batteries（AZIBs） are presented for future research.

关键词： AZIBs Current perspectives Electrolyte additives Regulation mechanism Zn metal anode

Crystal engineering regulation achieving inverse temperature symmetry breaking ferroelasticity in a cationic displacement type hybrid perovskite system

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Chinese Chemical Letters 2024年第5期35卷 477-481页

作者： na wang wang Luo Huaiyi Shen Huakai Li Zejiang Xu Zhiyuan Yue Chao Shi Hengyun Ye Leping Miao Chaotic Matter Science Research Center Department of MaterialsMetallurgy and ChemistryJiangxi University of Science and TechnologyGanzhou 341000China

Ferroelastic hybrid perovskite materials have been revealed the significance in the applications of switches,sensors,actuators,***,it remains a challenge to design high-temperature ferroelastic to meet the requirements for the practical ***,we reported an one-dimensional organicinorganic hybrid perovskites(OIHP)(3-methylpyrazolium)CdCl_(3)(3-MBCC),which possesses a mmmF2/m ferroelastic phase transition at 263 ***,utilizing crystal engineering,we replace-CH_(3) with-NH_(2) and-H,which increases the intermolecular force between organic cations and inorganic *** phase transition temperature of(3-aminopyrazolium)CdCl_(3)(3-ABCC),and(pyrazolium)CdCl_(3)(BCC)increased by 73 K and 10 K,***,BCC undergoes an unconventional inverse temperature symmetry breaking(ISTB)ferroelastic phase transition around 273 ***,it transforms from a high symmetry low-temperature paraelastic phase(point group 2/m)to a low symmetry high-temperature ferroelastic phase(point group ī)originating from the rare mechanism of displacement of organic cations phase *** means that crystal BCC retains in ferroelastic phase above 273 K until melting point(446 K).Furthermore,characteristic ferroelastic domain patterns on crystal BCC are confirmed with polarized optical *** study enriches the molecular mechanism of ferroelastics in the family of organic-inorganic hybrids and opens up a new avenue for exploring high-temperature ferroic materials.

关键词： Organic-inorganic hybrid perovskite Crystal engineering Inverse temperature symmetry breaking Displacement type phase transition Ferroelasticity

MdbHLH162 connects the gibberellin and jasmonic acid signals to regulate anthocyanin biosynthesis in apple

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Journal of Integrative Plant Biology 2024年第2期66卷 265-284页

作者： Jian-Ping An Rui-Rui Xu Xiao-na wang Xiao-Wei Zhang Chun-Xiang You Yuepeng Han Apple technology innovation center of Shandong Province College of Horticulture Science and EngineeringShandong Agricultural UniversityTai-An 271018China CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical GardenHubei Hongshan LaboratoryThe Innovative Academy of Seed Design of Chinese Academy of SciencesWuhan 430074China College of Biology and Oceanography Weifang UniversityWeifang 261061China

Anthocyanins are secondary metabolites induced by environmental stimuli and developmental *** positive regulators of anthocyanin biosynthesis have been reported,whereas the anthocyanin repressors have been *** the signal transduction pathways of gibberellin(GA)and jasmonic acid(JA)and their regulation of anthocyanin biosynthesis have been investigated,the cross-talk between GA and JA and the antagonistic mechanism of regulating anthocyanin biosynthesis remain to be *** this study,we identified the anthocyanin repressor MdbHLH162 in apple and revealed its molecular mechanism of regulating anthocyanin biosynthesis by integrating the GA and JA ***162 exerted passive repression by interacting with MdbHLH3 and MdbHLH33,which are two recognized positive regulators of anthocyanin ***162 negatively regulated anthocyanin biosynthesis by disrupting the formation of the anthocyanin-activated MdMYB1-MdbHLH3/33complexes and weakening transcriptional activation of the anthocyanin biosynthetic genes MdDFR and MdUF3GT by MdbHLH3 and *** GA repressor MdRGL2a antagonized MdbHLH162-mediated inhibition of anthocyanins by sequestering MdbHLH162 from the MdbHLH162-MdbHLH3/33 *** JA repressors MdJAZ1 and MdJAZ2 interfered with the antagonistic regulation of MdbHLH162 by MdRGL2a by titrating the formation of the MdRGL2a-MdbHLH162 *** findings reveal that MdbHLH162 integrates the GA and JA signals to negatively regulate anthocyanin *** study provides new information for discovering more anthocyanin biosynthesis repressors and explores the cross-talk between hormone signals.

关键词： anthocyanin biosynthesis bHLH transcription factor gibberellin jasmonic acid regulatory network transcriptional regulation