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First application of large reactivity measurement through rod drop based on three-dimensional space–time dynamics

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Nuclear Science and Techniques 2021年第2期32卷 11-23页

作者： wen-Cong Wang Li-Yuan huang Cai-Xue Liu Han feng Jiang Niu Qi-Dong Dai Guo-En Fu Lin-feng Yang Ming-Chang Wu Nuclear Power Institute of China Chengdu 610041China

Abstract Reactivity measurement is an essential part of a zero-power physics test,which is critical to reactor design and *** rod drop experimental technique is used to measure the control rod worth in a zero-power physics *** conventional rod drop experimental technique is limited by the spatial effect and the difference between the calculated static reactivity and measured dynamic reactivity;thus,the method must be *** this study,a modified rod drop experimental technique that constrains the detector neutron flux shape function based on three-dimensional space–time dynamics to reduce the reactivity perturbation and a new method for calculating the detector neutron flux shape function are *** factors were determined using Monte Carlo N-particle transport code and transient analysis code for a pressurized water reactor at the Ulsan National Institute of Science and Technology and Xi’an Jiaotong University,and a large reactivity of over 2000 pcm was measured using the modified *** research evaluated the modified technique accuracy,studied the influence of the correction factors on the modification,and investigated the effect of constraining the shape function on the reactivity perturbation reduction caused by the difference between the calculated neutron flux and true value,using the new method to calculate the shape function of the detector neutron flux and avoiding the neutron detector response function(weighting factor)calculation.

关键词： Large reactivity measurement Rod drop technique Space-time dynamics Constrained shape function Monte Carlo N-particle

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定窑遗址出土制瓷原料的科学分析

光谱学与光谱分析 2025年第1期45卷 72-81页

作者：陈殿崔剑锋秦大树黄信李鑫北京师范大学历史学院陶瓷考古与艺术研究中心北京100875 考古科学教育部重点实验室(北京大学) 北京100871 浙大城市学院考古学系浙江杭州310015 河北省文物考古研究院河北石家庄050031 中国社会科学院考古研究所北京100101

首次通过窑址发掘出土的制瓷原料,复原了定窑不同时代的胎釉配方。对2009年定窑作坊遗址考古发掘所出五代至宋金时期二十余种制瓷原料开展了ED-XRF成分分析和XRD结构分析等光谱学分析。ED-XRF成分分析显示,这些原料可能包括单一原料和... 详细信息

首次通过窑址发掘出土的制瓷原料,复原了定窑不同时代的胎釉配方。对2009年定窑作坊遗址考古发掘所出五代至宋金时期二十余种制瓷原料开展了ED-XRF成分分析和XRD结构分析等光谱学分析。ED-XRF成分分析显示,这些原料可能包括单一原料和混合原料两种。其中单一原料包括岩石、粘土以及草木灰。混合原料则包括胎料和釉料两种。XRD结构分析表明用于定窑白瓷生产高岭土类原料是含有蒙脱石和方解石的伴生石英的长石类矿物原料。高铁粘土类原料由于铁含量特别高,应当是用于配黑釉的粘土。钙质原料的分析与康葆强等学者对定窑配釉用的灰料可能使用了40%的白灰和60%的松木灰配制的结论相同。同时,还发现了釉灰,即草木煅烧石灰石后形成的混合灰料。在分析定窑白瓷釉时,认为五代的白瓷釉可能使用了釉灰配制,因此定窑釉灰的使用可能推早到五代,这是目前发现使用釉灰配釉最早的实例。对制胎原料XRD晶相分析的结果表明,除了石英和高岭石占主要比重外,还含有长石、蒙脱石、方解石等岩石类矿物。从对单一原料的X射线衍射的分析结果看,石英是粘土以及岩石这类单一原料中都含有的一类矿物,因此可能石英并非必须要添加的胎体原料。石英和高岭石是粘土原料中的主要成分,因此制胎原料应该主要以岩石类原料和粘土作为主要配料。定窑细白瓷胎料可能使用了粘土类原料配合第一类岩石类原料的配方,其配比在金代时大约为1∶1左右,北宋时期可能约为7∶3(粘土∶岩石),五代时大概为6∶4左右。对制釉原料分析结果表明,定窑配釉原料是岩石类原料与釉灰配合形成的,五代、北宋时岩石和灰的比例约为9∶1,金代时石:灰达到了9.5∶0.5。这使得我们对定窑鼎盛时期的白瓷胎釉配方有了更加清晰的了解,从而为开展定窑的复烧提供了确凿的依据。

关键词：定窑制瓷原料光谱学分析

3D-printed porous functional composite scaffolds with polydopamine decoration for bone regeneration

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Regenerative Biomaterials 2023年第1期10卷 1233-1247页

作者： Jinn Qi Yili Wang Liping Chen Linjie Chen feng wen Lijiang huang Pfukwa Rueben Chunwu Zhang Huaqiong Li Department of Orthopaedics Joint Centre of Translational MedicineThe First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang 325035P.R.China Joint Centre of Translational Medicine Zhejiang Engineering Research Center for Tissue Repair MaterialsWenzhou InstituteUniversity of Chinese Academy of SciencesWenzhouZhejiang 325011P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China The Second Affiliated Hospital of wenzhou Medical University WenzhouZhejiang 325035P.R.China The Affiliated Xiangshan Hospital of wenzhou Medical University NingboZhejiang 315700P.R.China Department of Chemistry and Polymer Science Stellenbosch UniversityMatielandStellenbosch 7602South Africa

Large size bone defects affect human health and remain a worldwide health problem that needs to be solved immediately.3D printing technology has attracted substantial attention for preparing penetrable multifunctional scaffolds to promote bone reconditioning and *** by the spongy structure of natural bone,novel porous degradable scaffolds have been printed using polymerization of lactide and caprolactone(PLCL)and bioactive glass 45S5(BG),and polydopamine(PDA)was used to decorate the PLCL/BG *** physicochemical properties of the PLCL/BG and PLCL/BG/PDA scaffolds were measured,and their osteogenic and angiogenic effects were characterized through a series of experiments both in vitro and in *** results show that the PLCL/BG2/PDA scaffold possessed a good compression modulus and brilliant *** proliferation,adhesion and osteogenesis of hBMSCs were improved in the PDA coating groups,which exhibited the best *** results of the SD rat cranium defect model indicate that PLCL/BG2/PDA obviously promoted osteointegration,which was further confirmed through immunohistochemical ***,PDA decoration and the sustained release of bioactive ions(Ca,Si,P)from BG in the 3D-printed PLCL/BG2/PDA scaffold could improve surface bioactivity and promote better osteogenesis and angiogenesis,which may provide a valuable basis for customized implants in extensive bone defect repair applications.

关键词： 3D printing bioactive glass composites polydopamine angiogenesis bone regeneration

Synthesis and characterization of BaMgAl_(10)O_(17):Eu～(2+)phosphor prepared by homogeneous precipitation

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Particuology 2010年第5期8卷 473-476页

作者： ZhanhuiZhang Jingang feng Zhiliang huang School of Materials Science and Engineering Wuhan Institute of Technolo~ No. 693 Xiongchu Street Wuhan Hubei 430073 China

A homogeneous precipitation process based on urea hydrolysis reaction was exploited to synthesize BaMgAl10O17：Eu2＋ phosphor. The process parameters, such as the dosage of urea, the calcination tem- peratures and the concentration of Eu2＋, were refined in light of the characterization of the products. The experimental results revealed that pure and well-crystallized BaMgAl10O17：Eu2＋ phosphor could be obtained at 1250℃, a much lower temperature than that for traditional solid-state reaction. The as-prepared phosphor particles were small in grain size, regular in morphology, and uniform in size distribution. Because of the high homogeneity of the process, the as-prepared phosphor exhibited stronger emission intensity and higher thermal stability than the sample prepared by solid-state reaction at 1600℃.

关键词： BaMgAl10O17:Eu2+ PhosphorHomogeneous precipitationLuminescent properties

An improved EMMS model for turbulent flow in pipe and its solution

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Particuology 2023年第5期76卷 1-12页

作者： Lin Zhang wen Lai huang Jianhua Chen State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing100190China

Based on the existing energy-minimization multi-scale(EMMS)model for turbulent flow in pipe,an improved version is proposed,in which not only a new radial velocity distribution is introduced but also the quantification of total dissipation over the cross-section of pipe is improved for the dominant mechanism of fully turbulent flow in *** four dynamic equality constraints and some other constraints are constructed but there are five parameters involved,leading to one free variable *** the compromise in competition between dominant mechanisms for laminar and fully turbulent flow in pipe respectively,the above four constructed dynamic equality constraints can be ***,the cases for turbulent flow in pipe with low,moderate and high Reynolds number are simulated by the improved EMMS *** numerical results show that the model can obtain reasonable results which agree well with the data computed by the direct numerical simulation and those obtained by *** illustrates that the improved EMMS model for turbulent flow in pipe is reasonable and the compromise in competition between dominant mechanisms is indeed a universal governing principle hidden in complex ***,one more EMMS model for a complex system is offered,pro-moting the further development of mesoscience.

关键词： Mesoscience EMMS Compromise in competition Dominant mechanism Turbulent flow in pipe

Morphology-Dependent Catalysis of CeO_(2)-Based Nanocrystal Model Catalysts

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Chinese Journal of Chemistry 2022年第15期40卷 1856-1866页

作者： Yang wen Qiuyu huang Zhenhua Zhang Weixin huang Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Zhejiang Key Laboratory for Reactive Chemistry on Solid SurfacesInstitute of Physical ChemistryZhejiang Normal UniversityJinhuaZhejiang 321004China Hefei National Laboratory for Physical Sciences at the Microscale Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes and Department of Chemical PhysicsUniversity of Science and Technology of ChinaHefeiAnhui 230026China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalianLiaoning 116023China

Comprehensive Summary Recent progress in colloidal synthesis has realized the preparations of uniform nanocrystal(NC)model catalysts with rich and well-controlled morphologies that were employed to explore structure-activity relationships of powder catalysts,similar to single-crystal-based model catalysts under ultrahigh vacuum conditions but can work at the same conditions as powder catalysts without the"materials gap"and"pressure gap".In this perspective,the CeO_(2)-based NC model catalysts with various morphologies are included and their relevant progresses are critically *** detailed descriptions of morphology-controlled synthesis and characterizations of uniform CeO_(2)NCs.

关键词： CeO_(2)naocrystals Model catalysts Surface chemistry Heterogeneous catalysis Structure-activity relationships

Sleep disorders in Alzheimer’s disease:the predictive roles and potential mechanisms

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Neural Regeneration Research 2021年第10期16卷 1965-1972页

作者： huang Kuang Yu-Ge Zhu Zhi-feng Zhou Mei-wen Yang Fen-Fang Hong Shu-Long Yang Department of Physiology College of MedicineNanchang UniversityNanchangJiangxi ProvinceChina Department of Nurse Nanchang University HospitalNanchangJiangxi ProvinceChina Department of Experimental Teaching Center Nanchang UniversityNanchangJiangxi ProvinceChina

Sleep disorders are common in patients with Alzheimer’s disease,and can even occur in patients with amnestic mild cognitive impairment,which appears before Alzheimer’s *** disorders further impair cognitive function and accelerate the accumulation of amyloid-βand tau in patients with Alzheimer’s *** present,sleep disorders are considered as a risk factor for,and may be a predictor of,Alzheimer’s disease *** that sleep disorders are encountered in other types of dementia and psychiatric conditions,sleep-related biomarkers to predict Alzheimer’s disease need to have high specificity and ***,we summarize the major Alzheimer’s disease-specific sleep changes,including abnormal non-rapid eye movement sleep,sleep fragmentation,and sleep-disordered breathing,and describe their ability to predict the onset of Alzheimer’s disease at its earliest *** the mechanisms underlying these sleep changes is also crucial if we are to clarify the role of sleep in Alzheimer’s *** paper therefore explores some potential mechanisms that may contribute to sleep disorders,including dysregulation of the orexinergic,glutamatergic,andγ-aminobutyric acid systems and the circadian rhythm,together with amyloid-β*** review could provide a theoretical basis for the development of drugs to treat Alzheimer’s disease based on sleep disorders in future work.

关键词： Alzheimer’s disease amyloid-βaccumulation circadian rhythm GABAergic system glutamatergic system non-rapid eye movement sleep orexinergic system sleep disorders sleep fragmentation sleep-disordered breathing

Analysis of DNA Methylation Level by Methylation-Sensitive Amplification Polymorphism in Half Smooth Tongue Sole(Cynoglossus semilaevis)Subjected to Salinity Stress

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Journal of Ocean University of China 2017年第2期16卷 269-278页

作者： LI Siping HE feng wen Haishen LI Jifang SI Yufeng LIU Mingyuan HE Huiwen huang Zhengju The Key Laboratory of Mariculture of Ministry of Education Fishery CollegeOcean University of ChinaQingdao 266003P.R.China

Increasingly arisen environmental constraints may contribute to heritable phenotypic variation including methylation changes,which can help the animals with development,growth and *** this study,we assessed the DNA methylation levels in three tissues(gonad,kidney and gill) of half smooth tongue sole under the salinity *** methylation-sensitive amplification polymorphism(MSAP) technique was applied to illustrate the regulation of epigenetic mechanism in environmental *** were subjected to 15 salinity treatment for 7 and 60 days,respectively.A total of 11259 fragments were amplified with 8 pairs of selective *** levels of methylated DNA in different tissues of females and males without salinity stress were analyzed,which were 32.76% and 47.32% in gonad;38.13% and 37.69% in kidney;37.58% and 34.96% in gill,*** addition,the significant difference was observed in gonad between females and males,indicating that discrepant regulation in gonadal development and differentiation may involve sex-related *** analysis showed that total and hemi-methylation were significantly decreased under 15 salinity for 7 days,probably resulting in up-regulating salt-tolerance genes expression to adjust salt *** the adjustment for 60 days,total and hemi-methylation prominently went back to its normal levels to obtain ***,full methylation levels were steady along with salinity stress to maintain the stability of gene ***,the data showed that gonads in females and gills in males were superior in *** a result,DNA methylation regulates tissue-specific epiloci,and may respond to salinity stress by regulating gene expression to maintain animal survival and activity.

关键词： DNA methylation diversity half smooth tongue sole salinity stress MSAP

FedFV: A Personalized Federated Learning Framework for Finger Vein Authentication

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Machine Intelligence Research 2023年第5期20卷 683-696页

作者： feng-Zhao Lian Jun-Duan huang Ji-Xin Liu Guang Chen Jun-Hong Zhao wen-Xiong Kang School of Automation Science and Engineering South China University of TechnologyGuangzhou 510641China GRG Banking Equipment Co.Ltd. Guangzhou 510663China School of Automation Guangdong University of Petrochemical TechnologyMaoming 525000China

Most finger vein authentication systems suffer from the problem of small sample ***,the data augmentation can alleviate this problem to a certain extent but did not fundamentally solve the problem of category *** the researchers resort to pre-training or multi-source data joint training methods,but these methods will lead to the problem of user privacy *** view of the above issues,this paper proposes a federated learning-based finger vein authentication framework(FedFV)to solve the problem of small sample size and category diversity while protecting user *** training under FedFV,each client can share the knowledge learned from its user′s finger vein data with the federated client without causing template *** addition,we further propose an efficient personalized federated aggregation algorithm,named federated weighted proportion reduction(FedWPR),to tackle the problem of non-independent identically distribution caused by client diversity,thus achieving the best performance for each *** thoroughly evaluate the effectiveness of FedFV,comprehensive experiments are conducted on nine publicly available finger vein *** results show that FedFV can improve the performance of the finger vein authentication system without directly using other client *** the best of our knowledge,FedFV is the first personalized federated finger vein authentication framework,which has some reference value for subsequent biometric privacy protection research.

关键词： Finger vein personalized federated learning privacy protection biometric authentication.