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Enhancing the anti-corrosion performance and biocompatibility of AZ91D Mg alloy by applying roughness pretreatment and coating with in-situ Mg(OH)_(2)/Mg-Al LDH

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Journal of Magnesium and Alloys 2024年第6期12卷 2520-2533页

作者： Zexi Shao Pubo Li Chao Zhang Bintao Wu Chan Tang Mangmang Gao School of Materials and New Energy Ningxia Key Laboratory of Photovoltaic MaterialsNingxia UniversityYinchuan750021PR China Department of Gastroenterology The Third Xiangya HospitalCentral South UniversityChangsha410000PR China

Corrosion-resistant and biocompatible films were fabricated on AZ91D Mg alloy substrates by varying their roughness levels using met-allographic preparation and subsequent hydrothermal *** coated films comprised a mixed structure of Mg(OH)_(2)and Mg-Al layered double hydroxides(LDH)and exhibited excellent *** film thickness increased with decreasing surface *** resistance was evaluated using potentiodynamic polarization and electrochemical impedance *** pretreat-ment influenced the chemical activity of the Mg alloy surface and helped modulate the dissolution rate of the Mg_(17)Al_(12)phase during the hydrothermal *** decreasing roughness of the Mg substrate,the Al^(3+)concentration gradually increased,accelerating the in-situ formation of the Mg(OH)_(2)/LDH composite coating and improving its crystallinity.A thick and dense Mg(OH)_(2)/LDH coating was synthesized on the Mg substrate with the least roughness,substantially improving the corrosion resistance of the AZ91D *** lowest corrosion current density((5.73±2.75)×10^(−8)A·cm^(−2))was achieved,which was approximately three orders of magnitude less than that of bare ***,the coating demonstrated biocompatibility with no evident cytotoxicity,cellular damage,and hemolytic *** study provides an effective method for preparing coatings on Mg alloy surfaces with excellent corrosion resistance and biocompatibility.

关键词： Magnesium alloy Roughness Corrosion resistance Layered double hydroxides Biocompatibility

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L_(1)-Smooth SVM with Distributed Adaptive Proximal Stochastic Gradient Descent with Momentum for Fast Brain Tumor Detection

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Computers, Materials & Continua 2024年第5期79卷 1975-1994页

作者： Chuandong Qin Yu Cao Liqun Meng School of Mathematics and Information science North Minzu UniversityYinchuan750021China ningxia Key Laboratory of Intelligent Information and Big Data Processing Yinchuan750021China

Brain tumors come in various types,each with distinct characteristics and treatment approaches,making manual detection a time-consuming and potentially ambiguous *** tumor detection is a valuable tool for gaining a deeper understanding of tumors and improving treatment *** learning models have become key players in automating brain tumor *** descent methods are the mainstream algorithms for solving machine learning *** this paper,we propose a novel distributed proximal stochastic gradient descent approach to solve the L_(1)-Smooth Support Vector Machine(SVM)classifier for brain tumor ***,the smooth hinge loss is introduced to be used as the loss function of *** avoids the issue of nondifferentiability at the zero point encountered by the traditional hinge loss function during gradient descent ***,the L_(1) regularization method is employed to sparsify features and enhance the robustness of the ***,adaptive proximal stochastic gradient descent(PGD)with momentum,and distributed adaptive PGDwithmomentum(DPGD)are proposed and applied to the L_(1)-Smooth *** computing is crucial in large-scale data analysis,with its value manifested in extending algorithms to distributed clusters,thus enabling more efficient processing ofmassive amounts of *** DPGD algorithm leverages Spark,enabling full utilization of the computer’s multi-core *** to its sparsity induced by L_(1) regularization on parameters,it exhibits significantly accelerated convergence *** the perspective of loss reduction,DPGD converges faster than *** experimental results show that adaptive PGD withmomentumand its variants have achieved cutting-edge accuracy and efficiency in brain tumor ***-trained models,both the PGD andDPGD outperform other models,boasting an accuracy of 95.21%.

关键词： Support vector machine proximal stochastic gradient descent brain tumor detection distributed computing

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THE LIMIT CYCLE BIFURCATIONS OF A WHIRLING PENDULUM WITH PIECEWISE SMOOTH PERTURBATIONS

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Acta Mathematica Scientia 2024年第3期44卷 1115-1144页

作者：杨纪华 School of Mathematics and Computer science Ningxia Normal UniversityGuyuan756000China ningxia Basic science Research Center of Mathematics Yinchuan750000China

This paper deals with the problem of limit cycles for the whirling pendulum equation x=y,y=sin x(cosx-r)under piecewise smooth perturbations of polynomials of cos x,sin x and y of degree n with the switching line x=*** upper bounds of the number of limit cycles in both the oscillatory and the rotary regions are obtained using the Picard-Fuchs equations,which the generating functions of the associated first order Melnikov functions ***,the exact bound of a special case is given using the Chebyshev *** the end,some numerical simulations are given to illustrate the existence of limit cycles.

关键词： whirling pendulum limit cycle Melnikov function Picard-Fuchs equation Chebyshev system

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Dynamic recrystallization mechanism, texture evolution development and mechanical characteristics of a Mg–8.7Gd–4.18Y–0.42Zr magnesium alloy by ECAP

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Progress in natural science:Materials International 2024年第2期34卷 376-388页

作者： Ling Zhang Yinglong Li School of Materials science and Engineering Northeastern University School of Mechanical and Engineering Ningxia Institute of Science and Technology

Equal channel angle pressing is recognized for its ability to refine alloy grains and alter grain orientation, thereby achieve better mechanical performance of the magnesium alloy. This study investigates the microstructures,dynamic recrystallization mechanism, texture development, and mechanical performance of GW94K(Mg–8.7Gd–4.18Y–0.42Zr wt. %) Mg alloy following ECAP-4 passes at 400°C and 3 mm/min. Results show that when high-temperature deformation is undertaken, twin formation is suppressed while dislocation slip is facilitated, increasing dislocation density during deformation. Following ECAP deformation, the sample displayed higher fracture elongation, TYS, and UTS than the as-solutioned GW94K alloy. In particular, the GW94K alloy performed well mechanically after ECAP-4 passes, with an ultimate TYS of 231 MPa, an UTS of 290 MPa, and an elongation of 14.8 %. DDRX and shear bands induce CDRX, both of which are important in plastic deformation. as well as in modifying microstructure and grain orientation during ECAP deformation.

关键词： Dynamic recrystallization mechanism Equal channel angular pressing Magnesium alloy Mechanical performance Mg-Gd-Y-Zr alloy Texture development

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Thermogravimetric characteristics of corn straw and bituminous coal copyrolysis based the ilmenite oxygen carriers

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Chinese Journal of Chemical Engineering 2024年第4期68卷 8-15页

作者： Pengxing Yuan Xiude Hu Jingjing Ma Tuo Guo Qingjie Guo College of Chemical Engineering Qingdao University of Science&TechnologyQingdao 266042China State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China

Herein,the co-pyrolysis reaction characteristics of corn straw(CS)and bituminous coal in the presence of ilmenite oxygen carriers(OCs)are investigated via thermogravimetry coupled with mass *** results reveal that the participation of OCs weakens the devolatilization intensity of *** the CS blending ratio is<50%,the mixed fuel exhibits positive synergistic *** fitting results according to the Coats-Redfern integral method show that the solid-solid interaction between OCs and coke changes the reaction kinetics,enhancing the co-pyrolysis reactivity at the high-temperature zone(750-950C).The synergistic effect is most prominent at a 30%CS blending ratio,with copyrolysis activation energy in the range of 26.35-40.57 kJ·mol^(-1).

关键词： Oxygen carrier Co-pyrolysis Biomass Coal

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An Opposition-Based Learning-Based Search Mechanism for Flying Foxes Optimization Algorithm

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Computers, Materials & Continua 2024年第6期79卷 5201-5223页

作者： Chen Zhang Liming Liu Yufei Yang Yu Sun Jiaxu Ning Yu Zhang Changsheng Zhang Ying Guo Software College Northeastern UniversityShenyang110169China School of Information science and Engineering Shenyang Ligong UniversityShenyang110159China China Telecom Digital Intelligence Technology Co. Ltd.Beijing100035China College of Computer science and Engineering Ningxia Institute of Science and TechnologyShizuishan753000China

The flying foxes optimization(FFO)algorithm,as a newly introduced metaheuristic algorithm,is inspired by the survival tactics of flying foxes in heat wave *** preferentially selects the best-performing *** tendency will cause the newly generated solution to remain closely tied to the candidate optimal in the search *** address this issue,the paper introduces an opposition-based learning-based search mechanism for FFO algorithm(IFFO).Firstly,this paper introduces niching techniques to improve the survival list method,which not only focuses on the adaptability of individuals but also considers the population’s crowding degree to enhance the global search ***,an initialization strategy of opposition-based learning is used to perturb the initial population and elevate its ***,to verify the superiority of the improved search mechanism,IFFO,FFO and the cutting-edge metaheuristic algorithms are compared and analyzed using a set of test *** results prove that compared with other algorithms,IFFO is characterized by its rapid convergence,precise results and robust stability.

关键词： Flying foxes optimization(FFO)algorithm opposition-based learning niching techniques swarm intelligence metaheuristics evolutionary algorithms

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MCIF-Transformer Mask RCNN:Multi-Branch Cross-Scale Interactive Feature Fusion Transformer Model for PET/CT Lung Tumor Instance Segmentation

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Computers, Materials & Continua 2024年第6期79卷 4371-4393页

作者： Huiling Lu Tao Zhou School of Medical Information&Engineering Ningxia Medical UniversityYinchuan750004China School of Computer science and Engineering North Minzu UniversityYinchuan750021China Key Laboratory of Image and Graphics Intelligent Processing of State Ethnic Affairs Commission NorthMinzu UniversityYinchuan750021China

The precise detection and segmentation of tumor lesions are very important for lung cancer computer-aided ***,in PET/CT(Positron Emission Tomography/Computed Tomography)lung images,the lesion shapes are complex,the edges are blurred,and the sample numbers are *** solve these problems,this paper proposes a Multi-branch Cross-scale Interactive Feature fusion Transformer model(MCIF-Transformer Mask RCNN)for PET/CT lung tumor instance segmentation,The main innovative works of this paper are as follows:Firstly,the ResNet-Transformer backbone network is used to extract global feature and local feature in lung *** pixel dependence relationship is established in local and non-local fields to improve the model perception ***,the Cross-scale Interactive Feature Enhancement auxiliary network is designed to provide the shallow features to the deep features,and the cross-scale interactive feature enhancement module(CIFEM)is used to enhance the attention ability of the fine-grained ***,the Cross-scale Interactive Feature fusion FPN network(CIF-FPN)is constructed to realize bidirectional interactive fusion between deep features and shallow features,and the low-level features are enhanced in deep semantic ***,4 ablation experiments,3 comparison experiments of detection,3 comparison experiments of segmentation and 6 comparison experiments with two-stage and single-stage instance segmentation networks are done on PET/CT lung medical image *** results showed that APdet,APseg,ARdet and ARseg indexes are improved by 5.5%,5.15%,3.11%and 6.79%compared with Mask RCNN(resnet50).Based on the above research,the precise detection and segmentation of the lesion region are realized in this *** method has positive significance for the detection of lung tumors.

关键词： PET/CT images instance segmentation mask RCNN interactive fusion transformer

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Frictional contact analysis of a rigid solid with periodic surface sliding on the thermoelectric material

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 179-196页

作者： Yali ZHANG Yueting ZHOU Shenghu DING School of Mathematics and Statistics Ningxia UniversityYinchuan 750021China School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai 200092China

Understanding and characterizing rough contact and wavy surfaces are essential for developing effective strategies to mitigate wear,optimize lubrication,and enhance the overall performance and durability of mechanical *** sliding friction contact problem between a thermoelectric(TE)half-plane and a rigid solid with a periodic wavy surface is the focus of this *** simplify the problem,we utilize mixed boundary conditions,leading to a set of singular integral equations(SIEs)with the Hilbert *** analytical solutions for the energy flux and electric current density are obtained by the variable transform method in the context of the electric and temperature *** contact problem for the elastic field is transformed into the second-kind SIE and solved by the Jacobi ***,the smoothness of the wavy contact surface ensures that there are no singularities in the surface contact stress,and ensures that it remains free at the contact *** on the plane strain theory of elasticity,the analysis primarily examines the correlation between the applied load and the effective contact *** distribution of the normal stress on the surface with or without TE loads is discussed in detail for various friction ***,the obtained results indicate that the in-plane stress decreases behind the trailing edge,while it increases ahead of the trailing edge when subjected to TE loads.

关键词： wavy surface periodic contact thermoelectric(TE)material Hilbert integral kernel

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Response of ecosystem carbon storage to land use change from 1985 to 2050 in the ningxia Section of Yellow River Basin,China

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Journal of Arid Land 2024年第1期16卷 110-130页

作者： LIN Yanmin HU Zhirui LI Wenhui CHEN Haonan WANG Fang NAN Xiongxiong YANG Xuelong ZHANG Wenjun College of Geographical sciences and Planning Ningxia UniversityYinchuan 750021China China-Arab Joint International Research Laboratory for Featured Resources and Environmental Governance in Arid Region Yinchuan 750021China ningxia Land Resources Surveying and Monitoring Institute Yinchuan 750002China State Key Laboratory of Efficient Production of Forest Resources Yinchuan 750002China ningxia Lingwu Baijitan National Nature Reserve Administration Yinchuan 751400China

Regional sustainable development necessitates a holistic understanding of spatiotemporal variations in ecosystem carbon storage(ECS),particularly in ecologically sensitive areas with arid and semi-arid *** this study,we calculated the ECS in the ningxia Section of Yellow River Basin,China from 1985 to 2020 using the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model based on land use *** further predicted the spatial distribution of ECS in 2050 under four land use scenarios:natural development scenario(NDS),ecological protection scenario(EPS),cultivated land protection scenario(CPS),and urban development scenario(UDS)using the patch-generating land use simulation(PLUS)model,and quantified the influences of natural and human factors on the spatial differentiation of ECS using the geographical detector(Geodetector).Results showed that the total ECS of the study area initially increased from 1985 until reaching a peak at 402.36×10^(6) t in 2010,followed by a decreasing trend to *** spatial distribution of ECS was characterized by high values in the eastern and southern parts of the study area,and low values in the western and northern *** 1985 and 2020,land use changes occurred mainly through the expansion of cultivated land,woodland,and construction land at the expense of unused *** total ECS in 2050 under different land use scenarios(ranked as EPS>CPS>NDS>UDS)would be lower than that in *** light was the largest contributor to the spatial differentiation of ECS,with soil type and annual mean temperature being the major natural driving *** of this study could provide guidance on the ecological construction and high-quality development in arid and semi-arid areas.

关键词： carbon storage land use change nighttime light Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model patch-generating land use simulation(PLUS)model geographical detector(Geodetector) Yellow River Basin

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To explore the mechanism of Yigong San anti-gastric cancer and immune regulation

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1965-1994页

作者： Dou-Dou Lu Ling Yuan Zhao-Zhao Wang Jian-Jun Zhao Yu-Hua Du Na Ning Guo-Qing Chen Shi-Cong Huang Yi Yang Zhe Zhang Yi Nan School of Clinical Medicine Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina College of Pharmacy Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Traditional Chinese Medicine College Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Department of Chinese Medical Gastrointestinal China-Japan Friendship HospitalBeijing 100029China Key Laboratory of ningxia Minority Medicine Modernization Ministry of Education Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina

BACKGROUND Yigong San(YGS)is a representative prescription for the treatment of digestive disorders,which has been used in clinic for more than 1000 ***,the mechanism of its anti-gastric cancer and regulate immunity are still remains *** To explore the mechanism of YGS anti-gastric cancer and immune *** Firstly,collect the active ingredients and targets of YGS,and the differentially expressed genes of gastric ***,constructed a protein-protein interaction network between the targets of drugs and diseases,and screened hub *** the clinical relevance,mutation and repair,tumor microenvironment and drug sensitivity of the hub gene were ***,molecular docking was used to verify the binding ability of YGS active ingredient and hub *** Firstly,obtained 55 common targets of gastric cancer and *** Kyoto Encyclopedia of Genes and Genomes screened the microtubule-associated protein kinase signaling axis as the key pathway and IL6,EGFR,MMP2,MMP9 and TGFB1 as the hub *** 5 hub genes were involved in gastric carcinogenesis,staging,typing and prognosis,and their mutations promote gastric cancer ***,molecular docking results confirmed that the components of YGS can effectively bind to therapeutic *** YGS has the effect of anti-gastric cancer and immune regulation.

关键词： Gastric cancer Yigong San Mechanism Immune

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