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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

Nonlinear Parametric Vibration of a Fluid-Conveying Pipe Flexibly Restrained at the Ends

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Acta Mechanica Solida Sinica 2020年第3期33卷 327-346页

作者： Qian li Wei liu kuan Lu Zhufeng Yue Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710129China

In this paper,the nonlinear parametric vibration of fluid-conveying pipes flexibly restrained at both ends and subjected to the pulsation flow excitation is *** nonlinear equation of motion is derived using Hamilton^principle by considering the Kevin-Voigt viscoelastic damping,the geometric nonlinearity and the translational and rotational springs supported at the *** mode functions and eigen-frequencies are determined by the assumed mode method according to the elastic boundary *** Galerkin method is implemented to obtain the natural frequencies and mode shapes of the pipe conveying fluid with different flow *** effects of flexibly restrained conditions on stability of the pipe are *** nonlinear responses of the pipe under pulsating flow excitation are solved by the direct numerical *** vibration behaviors are discussed in details,such as time history,frequency spectrum,phase-plane portrait,Poincare map and motion *** results show that the responses of sub-harmonic resonance and combination resonance can also be reflected in the rigidly supported *** 1/5,1/8 and 1/13 sub-harmonic resonances can occur at certain excitation frequencies of the nonlinear parametric vibration *** steady-state response amplitudes increase by a large margin and significantly affect the stability of the *** effects of different spring stiffness coefficients on the parametric resonance responses are *** larger translational springs and rotational stiffness coefficients,the resonance frequencies shift to higher regions and the resonance amplitudes may reduce by a certain extent in accordance with the rigid-body *** study can provide helpful guidance on the analysis and design of piping systems subject to vibrations.

关键词： Pipes conveying fluid Flexibly restrained Pulsating flow velocity Parametric resonance Period-n motion

A Musculoskeletal Modeling of Hand-foot Crawling with Different Heights

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Journal of Bionic Engineering 2020年第3期17卷 591-599页

作者： Meng li kuan Wang Wenxin Niu Shengnian Zhang Key Laboratory of Exercise and Health Sciences of Ministry of Education Shanghai University of SportsShanghai 200438China Yangzi Rehabilitation Hospital Tongji University School of MedicineShanghai 201619China Department of Rehabilitation Sciences Tongji University School of MedicineShanghai 20092China

As a bionic therapy,hand-foot crawling has been reported to be used for the rehabilitation of low back ***,there have been few relevant biomechanical studies about this type of *** purpose of this study was to calculate muscle activation and lumbar spinal load based on the examined limb kinematics and kinetics,which associated with hand-foot crawling at the different Centre of Mass(CoM)heights.A total of 14 men performed hand-foot crawling at three CoM *** kinematics and kinetics data were ***-way repeated measure analysis of variance was used to analyze the efFect of the CoM height on crawling *** crawling data from one subject at the three heights were used to calculate the muscle activation and compressive lumbar load with an OpenSim musculoskeletal *** CoM heights had no significant effect on kinematics,kinetics or muscle *** spinal load was larger at higher ***-foot crawling was associated with lower trunk muscle *** study helps us to understand hand-foot crawling from the perspective of *** findings from this study may help physical therapists choose hand-foot crawling as an appropriate exercise for patients with low back pain during early rehabilitation.

关键词： biomechanics crawling OpenSim muscle activity spinal load

Slip Flow on Graphene:Current Status and Perspective

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Journal of Thermal Science 2022年第4期31卷 1115-1134页

作者： CHEN kuan-Ting li Qin-Yi TAKAHASHI Koji Department ofAeronautics and Astronautics Kyushu UniversityFukuoka 819-0395Japan International Institute for Carbon-Neutral Energy Research(WPI-I2CNER) Kyushu UniversityFukuoka 819-0395Japan

Fast fluid transport on graphene has attracted a growing body of research due to a wide range of potential applications including thermal management,water desalination,energy harvesting,and ***,we critically review the theoretical,simulational,and experimental progress regarding the fluid slippage on *** on the summary of the past studies,we give perspectives on future research directions towards complete understanding and practical applications of slip flow on graphene.

关键词： slip flow graphene nanochannel simulation experiment

1-MCP结合低压静电场复合处理对红托竹荪保鲜效果的影响

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食品与发酵工业 2025年第1期51卷 250-258页

作者：李佳霖陈家齐赵吉春李富华明建西南大学食品科学学院重庆400715 西南大学宜宾研究院四川宜宾644000 川渝共建特色食品重庆市重点实验室重庆400715

为探究不同保鲜方式对红托竹荪贮藏品质的影响,该文以四川宜宾“红托竹荪”为试验材料,采用1-甲基环丙烯(1-methylcyclopropene,1-MCP)缓释贴纸、低压静电场(low voltage electrostatic field,LVEF)处理方式将红托竹荪贮藏于4℃,相对湿... 详细信息

为探究不同保鲜方式对红托竹荪贮藏品质的影响,该文以四川宜宾“红托竹荪”为试验材料,采用1-甲基环丙烯(1-methylcyclopropene,1-MCP)缓释贴纸、低压静电场(low voltage electrostatic field,LVEF)处理方式将红托竹荪贮藏于4℃,相对湿度75%的冷库,分析其对红托竹荪外观品质、生理指标、营养成分和相关酶活性的影响,并结合相关性分析和主成分分析探讨红托竹荪贮藏期间品质差异。贮藏12 d后,与对照组相比,1-MCP+LVEF组可以缓解硬度下降和质量损失,有效提高还原糖、总酚和可溶性蛋白质含量等营养物质保有率,显著减轻膜脂过氧化的程度,维持细胞完整性。主成分分析提取出2个主成分,累积贡献率达到95.14%,结果表明,失重率、硬度、还原糖、抗坏血酸过氧化物酶活性等是影响红托竹荪贮藏品质的关键指标。综上,1-MCP+LVEF处理能够更好地维持红托竹荪的采后贮藏品质。该研究旨在为红托竹荪保鲜技术的开发提供理论依据,为红托竹荪储运销售提供新的思路。

关键词：红托竹荪 1-甲基环丙烯低压静电场复合处理贮藏品质

大跨径预应力混凝土连续梁桥施工监控技术研究

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价值工程 2025年第1期44卷 62-64页

作者：查李剑上海同济检测技术有限公司上海201900

桥梁结构理想的几何线形与合理的内力状态不仅与设计有关,而且还依赖于科学合理的施工方法。如何通过施工时的浇筑过程的控制以及结构标高调整来获得预先设计的应力状态和几何线形,是大跨桥梁施工中非常关键的问题。因此,在对大跨度预... 详细信息

桥梁结构理想的几何线形与合理的内力状态不仅与设计有关,而且还依赖于科学合理的施工方法。如何通过施工时的浇筑过程的控制以及结构标高调整来获得预先设计的应力状态和几何线形,是大跨桥梁施工中非常关键的问题。因此,在对大跨度预应力混凝土桥梁施工过程中,为了保障其施工质量及安全性,应采取必要的监控技术对其进行检测。本文以实际工程为例,对监控技术进行总结,为类似大跨度预应力混凝土桥梁施工监控提供借鉴作用。

关键词：预应力混凝土悬臂桥梁施工监控

Effect of strip feeding into mold on fluid flow and heat transfer in continuous casting process

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Journal of Iron and Steel Research International 2020年第3期27卷 295-309页

作者： Ran Niu Bao-kuan li Zhong-qiu liu Xiang-long li School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

Steel strip feeding into the mold during continuous casting is known as an innovative *** newly applied technology is designed to further improve the slab *** analyze the complex phase change processes,molten sodium thiosulphate(Na2S2O3-5H2O)was used in the experimental investigation as a transparent analog for metallic ***,a numerical model incorporating fluid flow,heat transfer and phase change during strip feeding into the mold process was *** generalized enthalpy-based method was applied to describe the phase change behavior,and the porous media theory was used to model the blockage of fluid flow by the dendrites in the mushy zone between the strip and melt as well as the solidified shell and *** validated model was then used for the simulation of the real strip feeding into the mold process in an industrial *** whole shape of the strip under the effect of jet flow from the submerged entry nozzle(SEN)was *** show that the strip will reach a pseudo-steady state after experiencing steel sheath formation,steel sheath melting and strip melting *** using the feeding method that is the strip narrow side toward the SEN in the present condition,the strip immersion length can reach 4.5 m below the meniscus and the slab centerline temperature can be decreased by 21 K to a *** the strip feeding speed increased from 0.3 to 0.5 m/s,the minimum temperature of the centerline could be lowered by 4 K or so.

关键词： Steel strip feeding Generalized enthalpy method Solidification Melting Continuous casting

Defect-induced synthesis of nanoscale hierarchically porous metal-organic frameworks with tunable porosity for enhanced volatile organic compound adsorption

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Nano Materials Science 2024年第4期6卷 467-474页

作者： kuan liang Weibiao Guo linmei li Huidong Cai Haiqi Zhang Jingjing li Feng Xu jian Yan Daofei Lv Hongxia Xi Chongxiong Duan Guangdong Provincial Key Laboratory of Intelligent Food Manufacturing Foshan UniversityFoshan528231China School of Materials Science and Hydrogen Engineering Foshan UniversityFoshan528231China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou510640China School of Environmental and Chemical Engineering Foshan UniversityFoshan528231China

Nanoscale hierarchically porous metal-organic frameworks(NH-MOFs)synergistically combine the advantages of nanoscale MOFs and hierarchically porous MOFs,resulting in remarkable characteristics such as increased specific surface area,greater porosity,and enhanced exposure of active ***,nanoscale hierarchically porous UIO-66(UIO-66_X)was synthesized using a defect-induced strategy that employed ethylene diamine tetraacetic acid(EDTA)as a *** introduced EDTA occupies the coordination sites of organic ligands,promoting the formation and growth of UIO-66 crystal nuclei and inducing defects during *** as-synthesized UIO-66_X crystals exhibit a uniform distribution with an average size of approximately 100 *** addition,the total pore volume attains a remarkable value of 0.95 cm^(3)g^(-1),with mesopores constituting 36.8% of the ***,the porosities of UIO-66_X can be easily tuned by controlling the molar ratio of EDTA/Zr^(4+).In addition,the as-synthesized UIO-66_X exhibits excellent adsorption capacities for n-hexane(344 mg g^(-1))and pxylene(218 mg g^(-1)),which are 44.5% and 27.5% higher than those of conventional UIO-66,***,the adsorption behavior of n-hexane and p-xylene molecules in UIO-66_X was investigated using density functional theory simulations.

关键词： Nanoscale hierarchically porous MOFs Tunable porosities Enhanced VOC adsorption

Insulin-induced severe thyrotoxic periodic paralysis:A case report

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World Journal of Clinical Cases 2025年第7期13卷 46-51页

作者： Yan-li Wang jian li Department of Endocrinology and Metabolism Zigong First People's HospitalZigong 643000Sichuan ProvinceChina

BACKGROUND Thyrotoxic periodic paralysis(TPP)is an endocrine emergency caused by thyrotoxicosis,manifesting mainly as periodic myasthenia and hypokalemia,and posing a serious threat to the patient's ***,strenuous exercise,alcohol abuse,high carbohydrate intake and insulin injections are common triggers of *** article reports a case of severe TPP induced by insulin injection,elucidates the characteristics and pathogenesis of the disease,analyses the risk factors for triggering TPP,and hopefully provides more clinical data for TPP *** SUMMARY A 38-year-old Asian man presented to the emergency department with a oneweek history of limb weakness and worsening *** medical history included poorly controlled type 2 diabetes and he had been switched to Aspart50 a week *** was alert and oriented with upper extremity strength grade 3 and lower extremity strength grade *** department tests showed hypokalemia of 1.6 mmol/*** paramedics administered 1.5 g of potassium intravenously,followed by 4.0 g *** in the arms and legs *** was referred to endocrinology where he was diagnosed with Graves'disease,with suboptimal control and insulin injections possibly causing *** stopped his insulin and he was discharged with a potassium level of 4.0 mmol/*** Insulin is a trigger for TPP and should be avoided in patients with *** recognition and treatment of TPP is crucial,especially in patients presenting with hypokalemic periodic paralysis.

关键词： Thyrotoxic periodic paralysis Potassium metabolism disorders Insulin Triggers of paralysis Case report