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Thermal deformation behavior and microstructure evolution of modified IN617 alloy with different initial states

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Journal of Iron and Steel Research International 2021年第10期28卷 1315-1328页

作者： Qi Li Xin-liang Jiang zheng-zong Chen zheng-dong Liu liang Zuo Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang110819LiaoningChina Erzhong(Deyang)Heavy Equipment Co. Ltd.Deyang618000SichuanChina Institute for Special Steels China Iron and Steel Research InstituteBeijing100081China

The thermal deformation behaviors of the as-cast and wrought modified IN617 nickel-based heat-resistant alloys at different temperatures(1000–1180℃)and strain rates(0.01–1 s^(−1))were *** constitutive equation was established to describe the relationship of the flow stress,temperature,and strain rate during thermal *** effect of the thermal deformation conditions on the microstructure evolution of alloys was studied using electron backscatter *** results revealed that the thermal deformation activation energy of the as-cast alloy was greater than that of the wrought *** dynamic recrystallization(DRX)process is slow at intermediate strain rate(0.1 s^(−1))due to the comprehensive influence of various factors,such as the critical strain of DRX nucleation and stored *** DRX volume fraction increases with the improvement of deformation *** varied dynamic softening mechanisms induce the different thermal deformation behaviors of as-cast and wrought *** dynamic recovery,discontinuous dynamic recrystallization(DDRX)and nucleation at slip zone caused by strain incompatibility in grains were observed during thermal deformation of as-cast *** the process of thermal deformation of wrought alloys,DDRX was the primary dynamic crystallization *** continuous dynamic recrystallization was an auxiliary nucleation mechanism.

关键词： Nickel-based heat-resistant alloy Initial alloy state Thermal deformation Microstructure evolution Dynamic recrystallization nucleation mechanism

Yrast Bands Calculation for Odd-Odd Nuclei ^(160)Ho, ^(162)Tm and ^(164)Tm

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Chinese Physics Letters 1996年第7期13卷 504-507页

作者： ZHU Shun-quan zheng Ren-rong Department of Physics Southwest Normal UniversityChongqing 630715

In this paper,the axial symmetry rotor plus quasiparticle model is generalized from odd nuclei to odd-odd *** spectra of yrast bands for nuclei ^(160)Ho,^(162)Tm and ^(164)Tm are calculated by using the *** inversions in these three nuclei are reproduced,and one possible signature inversion mechanism connected with the calculation is also discussed.

关键词： method symmetry

A decision support system for satellite layout integrating multi-objective optimization and multi-attribute decision making

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Journal of Systems Engineering and Electronics 2019年第3期30卷 535-544页

作者： liang Yan’gang QIN zheng College of Aerospace Science and Engineering National University of Defense Technology

A decision support system, including a multi-objective optimization framework and a multi-attribute decision making approach is proposed for satellite equipment layout. Firstly, given three objectives (to minimize the C.G. offset, the cross moments of inertia and the space debris impact risk), we develop a threedimensional layout optimization model. Unlike most of the previous works just focusing on mass characteristics of the system, a space debris impact risk index is developed. Secondly, we develop an efficient optimization framework for the integration of computer-aided design (CAD) software as well as the optimization algorithm to obtain the Pareto front of the layout optimization problem. Thirdly, after obtaining the candidate solutions, we present a multi-attribute decision making approach, which integrates the smart Pareto filter and the correlation coefficient and standard deviation (CCSD) method to select the best tradeoff solutions on the optimal Pareto fronts. Finally, the framework and the decision making approach are applied to a case study of a satellite platform.

关键词： layout optimization satellite multi-objective optimization Pareto front multi-attribute decision making

X-ray excited Mn^(2+)-doped persistent luminescence materials with biological window emission for in vivo bioimaging

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Journal of Rare Earths 2024年第1期42卷 28-35,I0001页

作者： Hanrun zheng Lin Liu Yi’ang Li Rui rong liang Song Junpeng Shi Jing Teng Xia Sun Yun Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China University of the Chinese Academy of Sciences Beijing100049China Xiamen Hospital of Traditional Chinese Medicine Xiamen361015China Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou350108China

In recent years,persistent luminescence materials(PLMs)excited by X-rays and emitting in biological windows have received extensive attention in the field of high-sensitivity *** metal Mn^(2+)is an ideal emission center,but few studies focus on Mn^(2+)-doped PLMs with X-ray excitation and biological window ***,we report a Mn^(2+)-doped PLM,LiYGeO_(4):Mn^(2+)(LYGM),with excellent biological window persistent luminescence *** excitation by UV,LYGM produces a durable biological window of persistent luminescence emission at 660 nm for up to 20 *** *** can be repeatedly excited by X-rays,resulting in long-term biological window persistent luminescence *** addition,we obtain LYGM around 200 nm in diameter by ball milling and centrifugation and improve its biocompatibility by surface modification to apply it to in vivo imaging in *** LYGM are injected into mice through the tail vein,in situ excitation of X-rays can be *** the persistent luminescence decays,LYGM can be re-excited for repeated ***,LYGM shows potential prospects for in vivo deep tissue and long-term bioimaging.

关键词： Persistent luminescence X-ray Biological window In vivo imaging Rare earths

Coseismic Slip Distribution of the 2021 Mw7.4 Maduo,Qinghai Earthquake Estimated from InSAR and GPS Measurements

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Journal of Earth Science 2022年第4期33卷 885-891页

作者： Lihan Xiao Rui zheng rong Zou Institute of Geophysics and Geomatics China University of GeosciencesWuhan 430074China

On 22 May 2021,the Maduo Earthquake occurred on a branch fault of the East Kunlun fault in the Bayan Har Block,which provides opportunity to constrain fault geometry and strain accumulation and release for assessment of earthquake *** processed the Sentinal-1A/B SAR images acquired before and after the earthquake,with which we constrained a finite fault model to best fit to the combined data set of downsampled InSAR image and GPS *** inversion indicates that the Maduo event ruptured a 160 km long section striking 286.5°and a dipping 81.39°with rake angle of 4.62°.The model suggests three compact rupture areas with the slip amplitude exceeding 4 m on the main rupture section and the largest slip region is in the east of the epicenter with a slip of approximately 4.6 m below the surface,in a good agreement with the field geological *** total geodetic moment is 1.67×10^(20) N·m equivalent to Mw7.44,slightly larger than estimate of the USGS.

关键词： Maduo Earthquake geodetic measurements coseismic displacements slip distribution focal mechanism earthquakes

Nasopharyngeal carcinoma incidence and mortality in China,2013

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Chinese Journal of Cancer 2017年第12期36卷 686-693页

作者： Kuang-rong Wei rong-Shou zheng Si-Wei Zhang Zhi-Heng liang Zhu-Ming Li Wan-Qing Chen Cancer Institute of Zhongshan People’s Hospital ZhongshanGuangdong 528403P.R.China National Central Cancer Registry National Cancer CenterBeijing 100021P.R.China

Background: We estimated the incidence and mortality of nasopharyngeal carcinoma(NPC) in China in 2010 according to the data of 145 domestic population-based cancer registries in 2014, and no such reports since ***, to further and better understand its epidemiology in China and to provide more precise scientific information for its control and prevention in China, we analyzed the NPC incidence and mortality of 255 domestic populationbased cancer registries, and estimated the national rates in 2013 ***: NPC incidence and mortality data of 255 domestic cancer registries in 2013, accepted by the 2016 National Cancer Registry Annual Report, were collected and collated, and the indices of NPC such as the numbers of new cases and deaths, crude rates, age-standardized rates, and truncated rates of incidence and mortality were calculated and analyzed. The incidence and mortality in China and its constituent areas were estimated according to the national population in ***: An estimated 42,100 new cases and 21,320 deaths were attributed to NPC in China in 2013, accounting for1.14% of all new cancer cases and 0.96% of all cancer-related deaths that year in China. Crude incidence and mortality of NPC were 3.09/100,000 and 1.57/100,000, respectively. World age-standardized incidence and mortality were2.17/100,000 and 1.08/100,000, respectively. The incidence and mortality of males were obviously higher than those of females and slightly higher in urban areas than in rural areas. Among seven Chinese administrative regions, NPC incidence and mortality were obviously higher in South China than in other regions and lowest in North China. Top3 incidence and mortality provinces and registering areas all located in South China. The age-specific incidence and mortality rose quickly from age 25-29 and 35 to 39 years, respectively, peaked at different ages and varied by ***: These results demonstrated that NPC incidence and mortality in China in

关键词： Nasopharyngeal carcinoma Incidence Mortality China

Exercise preconditioning alleviates ischemia-induced memory deficits by increasing circulating adiponectin

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Neural Regeneration Research 2025年第5期20卷 1445-1454页

作者： Meifeng zheng Borui Zhang Sonata S Y Yau Kwok-Fai So Li Zhang Haining Ou Department of Rehabilitation Medicine Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Department of Rehabilitation Medicine The Fifth Clinical College of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Key Laboratory of CNS Regeneration(Ministry of Education) Guangdong-Hong Kong-Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina Department of Rehabilitation Sciences The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina State Key Laboratory of Brain and Cognitive Science Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionChina Center for Exercise and Brain Science School of PsychologyShanghai University of SportShanghaiChina Neuroscience and Neurorehabilitation Institute University of Health and Rehabilitation SciencesQingdaoShandong ProvinceChina

Cerebral ischemia is a major health risk that requires preventive approaches in addition to drug *** exercise enhances neurogenesis and synaptogenesis,and has been widely used for functional rehabilitation after *** this study,we determined whether exercise training before disease onset can alleviate the severity of cerebral *** also examined the role of exercise-induced circulating factors in these *** mice were subjected to 14 days of treadmill exercise training before surgery for middle cerebral artery *** found that this exercise pre-conditioning strategy effectively attenuated brain infarct area,inhibited gliogenesis,protected synaptic proteins,and improved novel object and spatial memory *** analysis showed that circulating adiponectin plays a critical role in these preventive effects of *** activation of adiponectin receptors by Adipo Ron mimicked the effects of exercise,while inhibiting receptor activation abolished the exercise *** summary,our results suggest a crucial role of circulating adiponectin in the effects of exercise pre-conditioning in protecting against cerebral ischemia and supporting the health benefits of exercise.

关键词： adiponectin cerebral ischemia exercise pre-conditioning hippocampus memory function middle cerebral artery occlusion prefrontal cortex synaptic proteins treadmill exercise

Multiscale classification and its application to process monitoring

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第6期11卷 425-434页

作者： Yu-ming LIU Lu-bin YE Ping-you zheng Xiang-rong SHI Bin HU Jun liang Institute of Industrial Control State Key Lab of Industrial Control Technology Zhejiang University Hangzhou 310027 China

Multiscale classification has potential advantages for monitoring industrial processes generally driven by events in different time and frequency *** this study, we adopt stationary wavelet transform for multiscale analysis and propose an applicable scale selection method to obtain the most discriminative scale *** using the multiscale features, we construct two classifiers:(1) a supported vector machine(SVM) classifier based on classification distance, and(2) a Bayes classifier based on probability *** the SVM classifier, we use 4-fold cross-validation and grid-search to obtain the optimal *** the Bayes classifier, we introduce dimension reduction techniques including kernel Fisher discriminant analysis(KFDA) and principal component analysis(PCA) to investigate their influence on classification *** tested the classifiers with two simulated benchmark processes:the continuous stirred tank reactor(CSTR) process and the Tennessee Eastman(TE) *** also tested them on a real polypropylene production *** performance comparison among the classifiers in different scales and scale combinations showed that when datasets present typical scale features, the multiscale classifier had higher classification accuracy than conventional single scale *** also found that dimension reduction can generally contribute to a better classification in our tests.

关键词： Multiscale analysis Stationary wavelet transform Multi-class classifier Feature extraction Process monitoring

Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng zheng Wang Ruisong Zhu Ruijie Liu Jiang Ma Lina Hu Weihua Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University College of Mechatronics and Control Engineering Shenzhen University Songshan Lake Materials Laboratory Institute of Physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning