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Interface property of dissimilar Ti-6Al-4V/AA1050 composite laminate made by non-equal channel lateral co-extrusion and heat treatment

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Defence Technology（防务技术） 2024年第3期33卷 197-208页

作者： Juan Liao Mengmeng tian Xin xue School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350116China

The purpose of this paper is to examine the effect of processing parameters and subsequent heat treatments on the microstructures and bonding strengths of Ti-6Al-4V/AA1050 laminations formed via a non-equal channel lateral co-extrusion *** microstructural evolution and growth mechanism in the diffusion layer were discussed further to optimize the bonding quality by appropriately adjusting process *** electron microscopes(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD)were used to characterize interfacial diffusion *** shear test was used to determine the mechanical properties of the interfacial diffusion *** experimental results indicate that it is possible to co-extrusion Ti-6Al-4V/AA1050 compound profiles using non-equal channel lateral *** heat treatment processes affect the thickness of the diffusion *** the temperature and time of heat treatment increase,the thickness of the reaction layers increases ***,the shear strength of the Ti-6Al-4V/AA1050 composite interface is proportional to the diffusion layer *** is observed that a medium interface thickness results in superior mechanical performance when compared to neither a greater nor a lesser interface *** characterization of all heat treatments reveals that the only intermetallic compound observed in the diffusion layers is TiAl_(3).Due to the inter-diffusion of Ti and Al atoms,the TiAl_(3) layer grows primarily at AA1050/TiAl_(3) interfaces.

关键词： Shear strength Co-extrusion Heat treatment Microstructure Intermetallic compounds

Mixed D-vine copula-based conditional quantile model for stochastic monthly streamflow simulation

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Water Science and Engineering 2024年第1期17卷 13-20页

作者： Wen-zhuo Wang Zeng-chuan Dong tian-yan Zhang Li Ren Lian-qing xue Teng Wu College of Water Resources and Hydrology Hohai UniversityNanjing 210098China Yellow River Research Center Hohai UniversityNanjing 210098China

Copula functions have been widely used in stochastic simulation and prediction of ***,existing models are usually limited to single two-dimensional or three-dimensional copulas with the same bivariate block for all *** address this limitation,this study developed a mixed D-vine copula-based conditional quantile model that can capture temporal *** model can generate streamflow by selecting different historical streamflow variables as the conditions for different months and by exploiting the conditional quantile functions of streamflows in different months with mixed D-vine *** up-to-down sequential method,which couples the maximum weight approach with the Akaike information criteria and the maximum likelihood approach,was used to determine the structures of multivariate Dvine *** developed model was used in a case study to synthesize the monthly streamflow at the Tangnaihai hydrological station,the inflow control station of the Longyangxia Reservoir in the Yellow River *** results showed that the developed model outperformed the commonly used bivariate copula model in terms of the performance in simulating the seasonality and interannual variability of *** model provides useful information for water-related natural hazard risk assessment and integrated water resources management and utilization.

关键词： Stochastic monthly streamflow simulation Mixed D-vine copula Conditional quantile model Up-to-down sequential method Tangnaihai hydrological station

Model-driven path planning for robotic plasma cutting of branch pipe with single Y-groove based on pipe-rotating scheme

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Advances in Manufacturing 2024年第1期12卷 94-107页

作者： yan Liu Qiu Tang Xin-Cheng tian School of Control Science and Engineering Shandong UniversityJinan250061People’s Republic of China Engineering Research Center of Intelligent Unmanned System Ministry of EducationJinan250061People’s Republic of China School of Mechanical and Electronic Engineering Shandong Jianzhu UniversityJinan250101People’s Republic of China

The automatic cutting of intersecting pipes is a challenging task in *** improved automation and accuracy,this paper proposes a model-driven path planning approach for the robotic plasma cutting of a branch pipe with a single ***,it summarizes the intersection forms and introduces a dual-pipe intersection *** on this model,the moving three-plane structure(a description unit of the geometric characteristics of the intersecting curve)is constructed,and a geometric model of the branch pipe with a single Y-groove is ***,a novel mathematical model for plasma radius and taper compensation is ***,the compensation model and groove model are integrated by establishing movable ***,to prevent collisions between the plasma torch and workpiece,the torch height is planned and a branch pipe-rotating scheme is *** the established models and moving frames,the planned path description of cutting robot is provided in this novel *** accuracy of the proposed method is verified by simulations and robotic cutting experiments.

关键词： Automatic groove cutting of intersecting pipes Model-driven robot path planning Plasma beam radius and taper compensation

Effect of different drying methods on the amino acids,α-dicarbonyls and volatile compounds of rape bee pollen

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Food Science and Human Wellness 2024年第1期13卷 517-527页

作者： yanxiang Bi Jiabao Ni Xiaofeng xue Zidan Zhou Wenli tian Valérie Orsat Sha yan Wenjun Peng Xiaoming Fang State Key Laboratory of Resource Insects Institute of Apicultural ResearchChinese Academy of Agricultural SciencesBeijing 100093China College of Engineering China Agricultural UniversityBeijing 100083China Bioresource Engineering Dept. McGill UniversitySte-Anne-de-Bellevue QC H9X 3V9Canada

The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and *** this study,the effects of five drying methods,namely,pulsed vacuum drying(PVD),freeze drying(FD),infrared drying(IRD),hot-air drying(HAD)and sun drying(SD)on free amino acids(FAAs),α-dicarbonyl compounds(α-DCs)and volatile compounds(VOCs)in rape bee pollen(RBP)were *** results showed that FD significantly released the essential amino acids(EAAs)compared with fresh samples while SD caused the highest *** was the dominantα-DCs in RBP and the highest loss was observed after *** were the dominant volatiles of RBP and SD samples contained more new volatile substances(especially aldehydes)than the other four drying ***,FD and PVD would be potential methods to effectively reduce the quality deterioration of RBP in the drying process.

关键词： Drying Bee pollen Free amino acids α-Dicarbonyl compounds Volatile compounds

Analyzing topics in social media for improving digital twinning based product development

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Digital Communications and Networks 2024年第2期10卷 273-281页

作者： Wenyi Tang Ling tian Xu Zheng Ke yan School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

Digital twinning enables manufacturers to create digital representations of physical entities,thus implementing virtual simulations for product *** efforts of digital twinning neglect the decisive consumer feedback in product development stages,failing to cover the gap between physical and digital *** work mines real-world consumer feedbacks through social media topics,which is significant to product *** specifically analyze the prevalent time of a product topic,giving an insight into both consumer attention and the widely-discussed time of a *** primary body of current studies regards the prevalent time prediction as an accompanying task or assumes the existence of a preset ***,these proposed solutions are either biased in focused objectives and underlying patterns or weak in the capability of generalization towards diverse *** this end,this work combines deep learning and survival analysis to predict the prevalent time of *** propose a specialized deep survival model which consists of two *** first module enriches input covariates by incorporating latent features of the time-varying text,and the second module fully captures the temporal pattern of a rumor by a recurrent network ***,a specific loss function different from regular survival models is proposed to achieve a more reasonable *** experiments on real-world datasets demonstrate that our model significantly outperforms the state-of-the-art methods.

关键词： Digital twinning Product development Topic analysis Social media

Integrating machine learning and CALPHAD method for exploring low-modulus near-β-Ti alloys

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Rare Metals 2024年第1期43卷 309-323页

作者： Hao Zou Yue-yan tian Li-Gang Zhang Ren-Hao xue Zi-Xuan Deng Ming-Ming Lu Jian-Xin Wang Li-Bin Liu School of Computer Science and Engineering Central South UniversityChangsha 410083China School of Materials Science and Engineering Central South UniversityChangsha 410083China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Traditional theoretical and empirical calculation methods can guide the design of β-and metastable β-alloys for bio-titanium. However, it is still difficult to obtain novel near-β-Ti alloys with low modulus. This study developed a method that combines machine learning with calculation of phase diagrams(CALPHAD) to facilitate the design of near-β-Ti alloys. An elastic modulus database of Ti–Nb–Zr–Mo–Ta–Sn system was constructed first, and then three features(the electron to atom ratio, mean absolute deviation of atom mass, and mean electronegativity) were selected as the key factors of modulus by performing a three-step feature selection. With these features, a highly accurate model was built for predicting the modulus of near-β-Ti alloys. To further ensure the accuracy of modulus prediction, machine learning with the elastic constants calculated was leveraged by CALPHAD database. The root mean square error of the well-trained model can be as low as 6.75 GPa. Guided by the prediction of machine learning and CALPHAD, three novel near-β-Ti alloys with elastic modulus below 50 GPa were successfully designed in this study. The best candidate alloy(Ti–26Nb–4Zr–4Sn–1Mo–Ta) exhibits an ultra-low modulus(36.6 GPa) after cold rolling with a thickness reduction of 20%. Our method can greatly save time and resources in the development of novel Ti alloys, and experimental verifications have demonstrated the reliability of this method.

关键词： Near-β-Ti alloy Machine learning Calculation of phase diagram Low-modulus alloy Feature selection

Positron Emission Tomography Imaging of Synaptic Dysfunction in Parkinson’s Disease

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Neuroscience Bulletin 2024年第6期40卷 743-758页

作者： Jiaqi Niu yan Zhong Chentao Jin Peili Cen Jing Wang Chunyi Cui Le xue Xingyue Cui Mei tian Hong Zhang Department of Nuclear Medicine and PET Center The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou310009China Institute of Nuclear Medicine and Molecular Imaging Zhejiang UniversityHangzhou310009China Key Laboratory of Medical Molecular Imaging of Zhejiang Province Hangzhou310009China College of Biomedical Engineering&Instrument Science Zhejiang UniversityHangzhou310014China Key Laboratory for Biomedical Engineering of Ministry of Education Zhejiang UniversityHangzhou310014China Huashan Hospital and Human Phenome Institute Fudan UniversityShanghai200040China

Parkinson’s disease(PD)is one of the most common neurodegenerative diseases with a complex *** formed by abnormal deposition of alpha-synuclein(αSyn)lead to synapse dysfunction of the dopamine and non-dopamine *** loss of dopaminergic neurons and concomitant alterations in non-dopaminergic function in PD constitute its primary pathological *** emission tomography(PET),as a representative molecular imaging technique,enables the non-invasive visualization,characterization,and quantification of biological processes at cellular and molecular *** synaptic function with PET would provide insights into the mechanisms underlying PD and facilitate the optimization of clinical *** this review,we focus on the synaptic dysfunction associated with theαSyn pathology of PD,summarize various related targets and radiopharmaceuticals,and discuss applications and perspectives of PET imaging of synaptic dysfunction in PD.

关键词： Parkinson’s disease Positron emission tomography Synapse dysfunction Alpha-synuclein Dopamine system Non-dopamine system

Hydrogel dressings on neurotrophic keratitis in an experimental animal model

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1396-1402页

作者： Hua-Qin Xia Xiao-Dan Jiang Yi-Fan Song xue-Min Li yan-Jie tian Department of Ophthalmology Peking University Third HospitalBeijing 100191China Beijing Key Laboratory of Restoration of Damaged Ocular Nerve Peking University Third HospitalBeijing 100191China

AIM:To investigate the therapeutic effects of hydrogel dressings on neurotrophic keratitis in ***:Male Wistar rats,aged 42–56d,were randomly divided into control,experimental,and treatment groups,each consisting of five *** experimental and treatment groups underwent neurotrophic keratitis modeling in both *** successful modeling,biomedical hydrogels formed with polyvinyl alcohol and polyvinyl pyrrolidone were used in treatment group for *** irritation response and keratitis index scores,Schirmer’s test,tear film break-up time(BUT),sodium fluorescein staining,and hematoxylin and eosin(HE)staining were used to evaluate the effectiveness of the ***:The neurotrophic keratitis model was successfully established in rats with severe ophthalmic nerve injury,characterized by keratitis,ocular irritation,reduced tear secretion measured by decreased BUT and Schirmer test values,corneal epithelial loss,and disorganized collagen fibers in the stromal *** treatment with hydrogel dressings,significant improvements were observed in keratitis scores and ocular irritation symptoms in model *** the recovery of tear secretion,as measured by the Schirmer’s test,did not show statistical differences,BUT was significantly *** staining confirmed a reduction in the extent of corneal epithelial loss after *** staining revealed the restoration of the structural disorder in both the epithelial and stromal layers to a certain ***:Hydrogel dressing reduces ocular surface irritation,improves tear film stability,and promotes the repair and restoration of damaged epithelial cells by maintaining a moist and clean environment on the ocular surface in the rat model.

关键词： neurotrophic keratitis hydrogel corneal epithelial cells rat

Miniaturized, Wide Stopband Filter Based on Shielded Capacitively Loaded SIW Resonators

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Chinese Journal of Electronics 2024年第2期33卷 456-462页

作者： yan ZHENG Hanyu tian Yuandan DONG University of Electronic Science and Technology of China (UESTC)

Based on the full-mode capacitively loaded substrate integrated waveguide（SIW） resonator and the miniaturized shielded half-mode capacitively loaded SIW（S-HMCSIW） cavities, a novel compact high-performance filter is proposed. The footprint of the half-mode SIW（HMSIW） is further reduced due to the application of the capacitive-loading technique. By applying cross coupling, the proposed SIW filter's transmission zero enhances the stopband rejection and shows excellent selectivity. For the bandpass filter, the measured |S21| and |S11| are better than 1.09 d B and-14 d B, respectively. And a 3-d B fractional bandwidth（FBW） of 9.14–10.76 GHz（FBW=16.2%）is also observed. The filter achieves a wide stopband with a-20 d B out-of-band rejection up to 2.69f0（f0= 10 GHz）,with a size of 0.39λg× 0.51λgonly. Good agreement between measurement and simulation is obtained.

关键词： Band-pass filters Wireless communication Couplings Resonator filters Microwave theory and techniques Filtering theory Passband