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THE EFFECT OF EC ON ORIENTATION AND RELAXATION OF PP OBTAINED VIA DYNAMIC PACKING INJECTION MOLDING

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Chinese Journal of Polymer Science 2005年第1期23卷 103-111页

作者： yongwang BingNa QiangFu CollegeofPolymerScienceandEngineering SichuanUniversityStateKeyLaboratoryofPolymerMaterialsEngineeringChengdu610065China

Abstract As a long term project aiming at engineering plastics based on polypropylene(PP),in this work,we report theeffect of ethylene-cellulose(EC)on the orientation and relaxation of PP obtained via dynamic packing injection molding(DPIM).2d-WAXD results showed that PP with a highly oriented structure and a shish-kebab structure were achieved byDIPM,leading to an increase of tensile strength from 35.0 MPa to 48.6 MPa.The degree of orientation of PP was increasedby adding only 1% of EC,resulting in a further increase of tensile strength from 48.6 MPa to 53.8 MPa.Shish wasfound to exist not only in the oriented layer but also in the core of the sample after adding EC,as evidenced by DSC result.This was understood as due to the overall decrease of viscosity by the addition of EC,thus an increasing of shear rate.Highershear rate can favor the orientation of molecules and continuous growth of shish structure,resulting in a change ofshish distribution along the sample thickness.On the other hand,the relaxation mode of shish in the melt re-crystallization of PP is also greatly affected by the presence of EC.A retarded relaxation of PP macromolecules was seen.Even more.SEM results showed that EC could form the short fibers in PP matrix along the shear flow direction.Comparedwith the morphology obtained by conventional injection molding,a much better dispersion and easy break-up of EC in PPmatrix were observed for samples obtained by dynamic packing injection molding.

关键词： PP/EC blends Shear Orientation Re-crystallization and relaxation.

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芦苇加筋土的轻型击实效果评价研究

河北水利电力学院学报 2024年第2期34卷 1-7,26页

作者：路维任永旺徐虎南宋兴海金坎辉河北水利电力学院土木工程系河北省沧州市061001 沧州交发建筑工程技术有限公司河北省沧州市061000 沧州交发工程项目管理有限责任公司河北省沧州市061000

文中针对渤海新区盐渍土的强度和变形问题开展了一系列试验研究,首先将渤海新区盐渍土与不同长度和加筋率的芦苇均匀拌和,按照一定的击实功对其进行轻型击实试验,随后为测试击实效果将其进行无侧限抗压强度试验。试验结果显示,质量加筋... 详细信息

文中针对渤海新区盐渍土的强度和变形问题开展了一系列试验研究,首先将渤海新区盐渍土与不同长度和加筋率的芦苇均匀拌和,按照一定的击实功对其进行轻型击实试验,随后为测试击实效果将其进行无侧限抗压强度试验。试验结果显示,质量加筋率对试验结果影响显著,最大干密度会随着加筋率增加而逐渐降低,降低幅度在每级0.01~0.02 g/cm^(3)之间,同时质量加筋率对最优含水率也有较大影响,最优含水率会随着芦苇掺量的增加而增加,这个趋势会随着加筋率的增大而缩减,当质量加筋率达到0.3%~0.35%时,最优含水率之间的最大差值仅为0.38%,此时可以忽略芦苇掺量对最优含水率的影响。同样加筋长度也对击实试验有较为显著的影响,芦苇加筋土的最大干密度随着加筋长度在减小,干密度会逐渐降低并呈近线性趋势下降,每一级加筋长度约下降0.01~0.02 g/cm^(3)。加筋长度较小时,最优含水率随加筋长度呈近线性增长趋势,当加筋长度达到50 mm时,最优含水率的变化受加筋率的影响较为稳定,加筋长度过长时,质量加筋率过大可能会导致最优含水率的下降,最明显的位置出现在加筋长度为70 mm、加筋率为0.35%处。根据无侧限抗压强度试验,可确定芦苇加筋土的最佳加筋长度和最佳质量加筋率为50 mm和0.25%。

关键词：芦苇加筋土轻型击实无侧限抗压强度

Effect of Zr and Ti on isothermal oxidation behavior of Nb–Si based alloys

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Progress in Natural Science:Materials International 2022年第2期32卷 226-235页

作者： Ankang Sun Ziqiang Dong Shuang Yang Jintao Shu Yanjie Liu Yi Liu yongwang Kang Dinggang Wang Jinxia Song Materials Genome Institute Shanghai University Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

The isothermal oxidation behavior of 56 Nb-16 Si-(20-x)Ti-3 Cr-3 Al-2 Hf-xZr(x=0,2,5,10 at.%) alloys was investigated at 800℃ and 1250℃,respectively.The results show that increasing the Zr content evidently increased the oxidation rates at 800℃,accompanied by the obvious occurrence of pesting oxidation.The alloys showed alike linear oxidation kinetics at 1250℃.With the increase of Zr content,the adherence and integrity of oxide scales were improved,but the overall oxidation resistance was slightly deteriorated.The observed oxidation behavior may be attributed to the composition variation of Zr and Ti in the alloys.The oxidation mechanism associated with the composition variation is discussed in this study.

关键词： Niobium Silicide Oxidation Zirconium Titanium

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基于计量急救包智能仓储控制系统建模和分析

微型电脑应用 2024年第5期40卷 100-103页

作者：刘海斌张永旺欧振国邓珊舒晔广东电网有限责任公司计量中心广东广州510000

为了满足计量急救包智能仓储控制系统高可靠、高稳定性使用的需求,构建计量急救包智能仓储控制系统模型,实现对国家电网仓储建设的智能管理。使用广域网硬件加速系统、用户管理系统和通用防火墙系统提供综合管理机制,确保计量急救包智... 详细信息

为了满足计量急救包智能仓储控制系统高可靠、高稳定性使用的需求,构建计量急救包智能仓储控制系统模型,实现对国家电网仓储建设的智能管理。使用广域网硬件加速系统、用户管理系统和通用防火墙系统提供综合管理机制,确保计量急救包智能仓储控制系统的稳定运行。计量急救包智能仓储控制系统建设模型可以精确地完善仓储控制系统的建设,实现仓储控制智能化,对电网的仓储建设发展和智能控制设施的建设有显著的效果。

关键词：计量急救包智能仓储控制系统建设

Speeding up the prediction of C-O cleavage through bond valence and charge on iron carbides

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矿物冶金与材料学报:英文版 2023年第10期30卷 2014-2024页

作者： Yurong He Kuan Lu Jinjia Liu Xinhua Gao Xiaotong Liu yongwang Li Chunfang Huo James P.Lewis Xiaodong Wen Ning Li Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Information Science&Technology UniversityBeijing 101400China State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021China State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China National Energy Center for Coal to Liquids Synfuels China Co.Ltd.Beijing 101400China Hong Kong Quantum AI Laboratory Ltd.University of Hong KongHong Kong 999077China

The activation of CO on iron-based materials is a key elementary reaction for many chemical processes.We investigate CO adsorption and dissociation on a series of Fe,Fe_(3)C,Fe_(5)C_(2),and Fe_(2)C catalysts through density functional theory calculations.We detect dramatically different performances for CO adsorption and activation on diverse surfaces and sites.The activation of CO is dependent on the local coordination of the molecule to the surface and on the bulk phase of the underlying catalyst.The bulk properties and the different local bonding environments lead to varying interactions between the adsorbed CO and the surface and thus yielding different activation levels of the C-O bond.We also examine the prediction of CO adsorption on different types of Fe-based catalysts by machine learning through linear regression models.We combine the features originating from surfaces and bulk phases to enhance the prediction of the activation energies and perform eight different linear regressions utilizing the feature engineering of polynomial representations.Among them,a ridge linear regression model with2nd-degree polynomial feature generation predicted the best CO activation energy with a mean absolute error of 0.269 eV.

关键词： adsorption CO activation iron carbides density functional theory

A survey on formal specification and verification of separation kernels

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Frontiers of Computer Science 2017年第4期11卷 585-607页

作者： yongwang ZHAO Zhibin YANG Dianfu MA State Key Laboratory of Software Development Environment (NLSDE) School of Computer Science and Engineering Beihang Univerisity Beijing 100191 China College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 210016 China

分离内核是安全和安全批评的系统的基本软件，它在分区之中象控制信息流动一样向他们的招待应用程序提供空间、时间的分离。在批评领域的分离核的应用程序由正式确认要求核的正确性。就我们的知识而言，这个话题上没有调查纸。这份报纸... 详细信息

分离内核是安全和安全批评的系统的基本软件，它在分区之中象控制信息流动一样向他们的招待应用程序提供空间、时间的分离。在批评领域的分离核的应用程序由正式确认要求核的正确性。就我们的知识而言，这个话题上没有调查纸。这份报纸给出正式说明的概述和分离核的确认。我们首先在不同的核之中包括分离核和比较的概念介绍背景。然后，自从 2000，我们在这个话题上调查现状。最后，我们由详细比较和讨论总结研究工作。

关键词：形式化验证形式化描述分离综述安全关键系统基础软件信息流应用

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硫磺菌醇提物抗氧化活性及其成分分析

食品工业 2024年第2期45卷 134-138页

作者：杨晶晶池延添易永旺林国峰曾亮魏奇宁德师范学院生命科学学院宁德352100 福建省科技厅产学研合作示范基地宁德352100 闽东特色生物资源福建省高校工程研究中心宁德352100

以清除1,1-二苯基苦基苯肼自由基(DPPH)、羟自由基、2,2-二氮-双(3-乙基苯并噻唑-6-磺酸)铵盐自由基(ABTS)、超氧阴离子自由基及还原能力为指标,对硫磺菌醇提物的抗氧化活性进行研究。结果表明:硫磺菌醇提物对DPPH自由基、羟自由基、ABT... 详细信息

以清除1,1-二苯基苦基苯肼自由基(DPPH)、羟自由基、2,2-二氮-双(3-乙基苯并噻唑-6-磺酸)铵盐自由基(ABTS)、超氧阴离子自由基及还原能力为指标,对硫磺菌醇提物的抗氧化活性进行研究。结果表明:硫磺菌醇提物对DPPH自由基、羟自由基、ABTS自由基和超氧阴离子自由基的清除能力的EC_(50)值分别是820.20μg/mL,3.81 mg/mL,317.09μg/mL和7.31 mg/mL。硫磺菌醇提物对羟自由基、ABTS自由基、超氧阴离子自由基和DPPH自由基均具有清除作用,并且具有一定的还原能力。硫磺菌醇提物中多糖含量较高达117.08±5.46 mg/g。

关键词：硫磺菌醇提物自由基抗氧化活性

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云芝多糖对肠道益生菌生长的影响

食品工业 2024年第1期45卷 76-79页

作者：陈镕坤池延添易永旺邓柳鸿曾亮魏奇宁德师范学院生命科学学院宁德352100 福建省科技厅产学研合作示范基地宁德352100

益生菌具有增强机体免疫力和维持肠道微生态平衡的作用。研究以云芝多糖为原料,探究云芝多糖对植物乳杆菌(Lactobacillus plantarum)、嗜热链球菌(Streptococcus thermophilus)、酪丁酸梭菌(Clostridium tyrobutyricum)和青春双歧杆菌(B... 详细信息

益生菌具有增强机体免疫力和维持肠道微生态平衡的作用。研究以云芝多糖为原料,探究云芝多糖对植物乳杆菌(Lactobacillus plantarum)、嗜热链球菌(Streptococcus thermophilus)、酪丁酸梭菌(Clostridium tyrobutyricum)和青春双歧杆菌(Bifidobacterium adolescentis)生长的影响,并且探究云芝多糖对这4种益生菌在模拟胃肠液中的耐受性。结果表明,云芝多糖能够促进青春双歧杆菌和酪丁酸梭菌的生长。云芝多糖可提高青春双歧杆菌对体外模拟胃液的耐受性。该研究可以为云芝多糖功能性食品的开发提供理论依据。

关键词：云芝多糖益生菌

Modeling and Stability Analysis of a Flexible Rotor Based on the Timoshenko Beam Theory

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Acta Mechanica Solida Sinica 2020年第3期33卷 281-293页

作者： yongwang Zhang Xiaodong Yang Wei Zhang Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical EngineeringBeijing University of Technology100124 BeijingChina

Based on the Timoshenko beam theory,a novel mathematical model of a rotating shaft with centrifugal terms is developed by using Hamilton^principle and Euler angles.The associated conventional model is provided for comparison purpose.The features of the proposed mathematical model are discussed based on some selected coordinate systems.The frequencies and modes are investigated to show the influences of centrifugal terms on the stability of the gyroscopic systems.The results show that the novel model proposed may lose stability due to the centrifugal terms.It is also found that the backward precession mode can be changed into a forward one beyond the critical rotating velocity.

关键词： Spinning Timoshenko beam Euler angles Centrifugal terms Stability analysis