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Heteroatom doping regulates the catalytic performance of singleatom catalyst supported on graphene for ORR

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Nano Research 2024年第3期17卷 1086-1093页

作者： Ji-Kai Sun yu-Wei Pan Meng-qian Xu Lei Sun Shaolong Zhang Wei-Qiao Deng dong Zhai Institute of Molecular Sciences and Engineering Institute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao 266237China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Replacing fossil fuels with fuel cells is a feasible way to reduce global energy shortages and environmental ***,the oxygen reduction reaction(ORR)at the cathode has sluggish kinetics,which limits the development of fuel *** is significant to develop catalysts with high catalytic activity of *** single-atom catalysts(SACs)of Pt supported on heteroatom-doped graphene are potential candidates for *** we studied the SACs of Pt with different heteroatoms doping and screened out Pt-C_(4) and Pt-C_(3)O_(1) structures with only 0.13 V overpotential for ***,it is found that B atoms doping could weaken the adsorption capacity of Pt,while N or O atoms doping could enhance *** regularity was verified on Fe *** the electronic interaction analysis between Pt and adsorbate,we explained the mechanism of this regularity and further proposed a new descriptor named corrected d-band center(ε_(d-corr))to describe *** descriptor is an appropriate reflection of the number of free electrons of the SACs,which could evaluate its adsorption *** work provides a purposeful regulatory strategy for the design of ORR catalysts.

关键词： single-atom catalyst(SAC) oxygen reduction reaction(ORR) heteroatom doping corrected d-band center descriptor

Biomimetic chitin hydrogel via chemical transformation

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Nano Research 2024年第2期17卷 771-777页

作者： Rui-Rui Liu qian-qian Shi yu-Feng Meng Yong Zhou Li-Bo Mao Shu-Hong yu Division of Nanomaterials&Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China College&Hospital of Stomatology Key Laboratory of Oral Diseases Research of Anhui ProvinceAnhui Medical UniversityHefei 230032China Department of Dental Implantology College&Hospital of StomatologyAnhui Medical UniversityHefei 230032China

Chitin hydrogel has been recognized as a promising material for various biomedical applications because of its biocompatibility and ***,the fabrication of strong chitin hydrogel remains a big challenge because of the insolubility of chitin in many solvents and the reduced chain length of chitin regenerated from *** herein introduce the fabrication of chitin hydrogel with biomimetic structure through the chemical transformation of chitosan,which is a water-soluble deacetylated derivative of *** reacetylation of the amino group in chitosan endows the obtained chitin hydrogel with outstanding resistance to swelling,degradation,extreme temperature and pH conditions,and organic *** chitin hydrogel has excellent mechanical properties while retaining a high water content(more than 95 wt.%).It also shows excellent antifouling performance that it resists the adhesion of proteins,bacteria,blood,and ***,as the initial chitosan solution can be feasibly frozen and templated by ice crystals,the chitin hydrogel structure can be either nacre-like or wood-like depending on the freezing method of the precursory chitosan *** to these anisotropic structures,such chitin hydrogel can exhibit anisotropic mechanics and mass transfer *** current work provides a rational strategy to fabricate chitin hydrogels and paves the way for its practical applications as a superior biomedical material.

关键词： chitin hydrogel biomimetic structure chemical stability mechanical strength antifouling

Contrasting strategies of optimizing carrier concentration in bulk InSe for enhanced thermoelectric performance

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Rare Metals 2024年第9期43卷 4425-4432页

作者： Hao-Nan Shi Shu-Lin Bai yu-Ping Wang Li-Zhong Su qian Cao Cheng Chang Li-dong Zhao School of Materials Science and Engineering Beihang University School of Materials Science and Engineering Taiyuan University of Science and Technology Huabei Cooling Device Co.Ltd.

Indium selenide (InSe),as a wide-bandgap semiconductor,has received extensive attention in the flexible electronics field in recent years due to its exceptional plasticity and promising thermoelectric ***,the low carrier concentration severely limits its thermoelectric performance *** this work,we conducted contrasting strategies that can be employed to increase the carrier concentration of InSe,including bandgap narrowing and heterovalent ***,the carrier concentration initially increases as a result of the reduced bandgap upon Te alloying and then slightly decreases due to the weak electronegativity of *** Br doping realizes high carrier concentration by pushing the Fermi level into the conduction bands and activating the multiple *** the other hand,both Te and Br obviously suppress the thermal conductivity due to the point defect *** contrast,Br doping realizes a higher thermoelectric performance with a maximum ZT of～0.13 at 773 K benefiting from the better optimization of carrier *** work elucidates the strategies for enhancing carrier concentration at anion sites and demonstrates the high efficiency of halogen doping in ***,the carrier concentration of InSe is promising to be further optimized,and future work should focus on employing approaches such as cation doping or secondphase compositing.

关键词： Bandgap Carrier concentration Heterovalent doping InSe Thermoelectric

Monotonic mechanical behaviour of compacted completely decomposed granite with various inclusion levels of incineration bottom ash

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第8期25卷 670-679页

作者： Han-Lin WANG Cheng-Shuang YIN qian-Yi ZHANG Qi-Wei LIU Zhen-yu YIN dong-Xing XUAN Askar KHASANOV Research Center for Advanced Underground Space Technologies of Hunan University Changsha 410082China Key Laboratory of Building Safety and Energy Efficiency of the Ministry of Education Hunan UniversityChangsha 410082China College of Civil Engineering Hunan UniversityChangsha 410082China School of Civil Engineering Zhengzhou UniversityZhengzhou 450001China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Department of Applied and Theoretical Mechanics Samarkand State UniversitySamarkandUzbekistan

1 Introduction Completely decomposed granite(CDG)is widely distributed in South China(Xu et al.,2022;Wang et al.,2023).The parent granite rock mass gradually loses features during the weathering process,and thus needs to be reinforced when used(Lan et al.,2003;Dassekpo et al.,2017;Alamanis et al.,2021).On the other hand,considering the huge demand for construction materials and limited natural resources,it is increasingly important to fully utilize solid waste(Gruhler et al.,2019;Anagnostopoulos et al.,2020;Jiang et al.,2022,2023a,2023b).With high strength and environment-friendly characteristics,incineration bottom ash(IBA)seems to be a suitable reinforcement material for CDG(Ahmed and Khalid,2011;Alhassan and Tankó,2012;Toraldo et al.,2013;Lynn et al.,2017;Xuan et al.,2018;Tang et al.,2020).

关键词： incineration behaviour utilize

Mechanical performance of 22SiMn2TiB steel welded with lowtransformation- temperature filler wire and stainless steel filler wire

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Journal of Iron and Steel Research International 2024年第4期31卷 967-981页

作者： Zi-dong Lin Kai-jie Song Zhen Sun Zi-qian Zhu Xue-feng Zhao Constantinos Goulas Wei Ya Xing-hua yu School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China Department of Design Production and Management Faculty of Engineering Technology.University of TwenteEnschede 7500 AETheNetherlands Rotterdam Additive Manufacture Fieldlab(RAMLAB) Rotterdam 3089 JWTheNetherlands

TX-80 low-transformation-temperature(LTT)welding wire was used to replace the traditional ER 307Si welding wire to realize the connection of 22SiMn2TiB armor steel in manual overlay *** previously existing issues,such as welding cracks,large welding deformation,and severe welding residual stress,were solved to ensure good strength and ductility *** particular,with the same welding conditions,TX-80 LTT wire eliminates welding *** reduces the welding deformation no matter the base pretreatment of pre-setting angle or no pre-setting *** comparison,it was found that the microstructure at the TX-80 weld is mainly composed of martensite and a small amount of retained *** contrast,the microstructure of the ER 307Si weld consists of a large amount of austenite and a small amount of skeleton-like *** variation trend of residual stress and microhardness from the weld to the base were investigated and compared with the mechanical properties of base *** TX-80 and the ER 307Si tensile samples elongation is 6.76%and 6.01%,while the ultimate tensile strengths are 877 and 667 MPa,*** average impact toughness at room temperature of the ER 307Si weld is 143.9 J/cm^(2),much higher than that of the TX-80 weld,which is only 36.7 J/cm^(2).The relationship between impact and tensile properties with microstructure species and distribution was *** addition,the fracture surface of the tensile and the impact samples was observed and *** dimples,fewer pores,larger radiation zone,and shear lips of TX-80 samples indicate better tensile ductility and worse impact toughness than those of ER 307Si weld.

关键词： Low-transformation-temperature material 22SiMn2TiB steel Welding deformation Residual stress Martensitic transformation Mechanical property

SwiftTheft: A Time-Efficient Model Extraction Attack Framework Against Cloud-Based Deep Neural Networks

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Chinese Journal of Electronics 2024年第1期33卷 90-100页

作者： Wenbin YANG Xueluan GONG Yanjiao CHEN qian WANG Jianshuo dong School of Cyber Science and Engineering Wuhan University School of Computer Science Wuhan University College of Electrical Engineering Zhejiang University

With the rise of artificial intelligence and cloud computing, machine-learning-as-a-service platforms,such as Google, Amazon, and IBM, have emerged to provide sophisticated tasks for cloud applications. These proprietary models are vulnerable to model extraction attacks due to their commercial value. In this paper, we propose a time-efficient model extraction attack framework called Swift Theft that aims to steal the functionality of cloud-based deep neural network models. We distinguish Swift Theft from the existing works with a novel distribution estimation algorithm and reference model settings, finding the most informative query samples without querying the victim model. The selected query samples can be applied to various cloud models with a one-time selection. We evaluate our proposed method through extensive experiments on three victim models and six datasets, with up to 16 models for each dataset. Compared to the existing attacks, Swift Theft increases agreement(i.e., similarity) by 8% while consuming 98% less selecting time.

关键词： Performance evaluation Cloud computing Analytical models Computational modeling Estimation Artificial neural networks Artificial intelligence

Predicting hepatocellular carcinoma: A new non-invasive model based on shear wave elastography

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World Journal of Gastroenterology 2024年第25期30卷 3166-3178页

作者： dong Jiang Yi qian Yi-Jun Gu Ru Wang Hua yu Hui dong dong-yu Chen Yan Chen Hao-Zheng Jiang Bi-Bo Tan Min Peng Yi-Ran Li Department of Ultrasound Eastern Hepatobiliary Surgery HospitalThe Third Affiliated Hospital of Naval Medical UniversityShanghai 200433China Department of Pathology Shanghai Eastern Hepatobiliary Surgery HospitalThird Affiliated Hospital of Naval Medical UniversityShanghai 200433China Department of College of Art and Science Case Western Reserve UniversityClevelandOH 44106United States Ultrasound Diagnosis PLA Naval Medical CenterShanghai 200437China

BACKGROUND Integrating conventional ultrasound features with 2D shear wave elastography(2D-SWE)can potentially enhance preoperative hepatocellular carcinoma(HCC)*** To develop a 2D-SWE-based predictive model for preoperative identification of *** A retrospective analysis of 884 patients who underwent liver resection and pathology evaluation from February 2021 to August 2023 was conducted at the Oriental Hepatobiliary Surgery *** patients were divided into the modeling group(n=720)and the control group(n=164).The study included conventional ultrasound,2D-SWE,and preoperative laboratory *** logistic regression was used to identify independent predictive factors for RESULTS In the modeling group analysis,maximal elasticity(Emax)of tumors and their peripheries,platelet count,cirrhosis,and blood flow were independent risk indicators for *** factors yielded an area under the curve of 0.77(95%confidence interval:0.73-0.81)with 84%sensitivity and 61%*** model demonstrated good calibration in both the construction and validation cohorts,as shown by the calibration graph and Hosmer-Lemeshow test(P=0.683 and P=0.658,respectively).Additionally,the mean elasticity(Emean)of the tumor periphery was identified as a risk factor for microvascular invasion(MVI)in malignant liver tumors(P=0.003).Patients receiving antiviral treatment differed significantly in platelet count(P=0.002),Emax of tumors(P=0.033),Emean of tumors(P=0.042),Emax at tumor periphery(P<0.001),and Emean at tumor periphery(P=0.003).CONCLUSION 2D-SWE’s hardness value serves as a valuable marker for enhancing the preoperative diagnosis of malignant liver lesions,correlating significantly with MVI and antiviral treatment efficacy.

关键词： Shear wave elastography Predicting model Microvascular invasion Antiviral treatment Hepatocellular carcinoma

Derivatives of Intersection Local Time for Two Independent Symmetricα-stable Processes

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1273-1292页

作者： Huan ZHOU Guang Jun SHEN qian yu Department of Mathematics Anhui Normal UniversityWuhu 241002P.R.China Department of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China Key Laboratory of Mathematical Modelling and High Performance Computing of Air Vehicles(NUAA) MIITNanjing 211106P.R.China

In this paper,we consider the derivatives of intersection local time for two independent d-dimensional symmetricα-stable processes X^(α) and X^(α)with respective indices α and α.We first study the sufficient condition for the existence of the derivatives,which makes us obtain the exponential integrability and H?lder *** we show that this condition is also necessary for the existence of derivatives of intersection local time at the ***,we also study the power variation of the derivatives.

关键词： Symmetric stable processes intersection local time exponential integrability power variation

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A systematic framework of constructing surrogate model for slider track peeling strength prediction

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Science China Technological Sciences 2024年第10期67卷 3261-3274页

作者： dong XingJian CHEN qian LIU WenBo WANG dong PENG ZhiKe MENG Guang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University KEIPER Seating Mechanisms Co. Ltd. Department of Industrial Engineering and Management Shanghai Jiao Tong University

Peeling strength can comprehensively reflect slider track safety and is crucial in car seat safety assessments. Current methods for determining slider peeling strength are primarily physical testing and numerical simulation. However, these methods encounter the potential challenges of high costs and overlong time consumption which have not been adequately addressed. Therefore, the efficient and low-cost surrogate model emerges as a promising solution. Nevertheless, currently used surrogate models suffer from inefficiencies and complexity in data sampling, lack of robustness in local model predictions, and isolation between data sampling and model prediction. To overcome these challenges, this paper aims to set up a systematic framework for slider track peeling strength prediction, including sensitivity analysis, dataset sampling, and model prediction. Specifically, the interpretable linear regression is performed to identify the sensitivity of various geometric variables to peeling strength. Based on the variable sensitivity, a distance metric is constructed to measure the disparity of different variable groups. Then, the sparsity-targeted sampling(STS) is proposed to formulate a representative dataset. Finally, the sequentially selected local weighted linear regression(SLWLR) is designed to achieve accurate track peeling strength prediction. Additionally, a quantitative cost assessment of the supplementary dataset is proposed by utilizing the minimum adjacent sample distance as a mediator. Experimental results validate the efficacy of sequential selection and the weighting mechanism in enhancing localization ***, the proposed SLWLR method surpasses similar approaches and other common surrogate methods in terms of prediction performance and data quantity requirements, achieving an average absolute error of 3.3 kN in the simulated test dataset.

关键词： slider track peeling strength surrogate model sensitivity analysis data sampling local weighted linear regression

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