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sedimentation acceleration of remanent iron oxide by magnetic flocculation

China Particuology 2007年第1期5卷 145-150页

作者： Mathias Stolarski Christian Eichholz Benjamin fuchs Hermann Nirschl Institute of Mechanical Process Engineering and Mechanics (MVM) University of Karlsruhe 76131 Karlsruhe Germany DuPont Experimental Station Building E304 Wilmington DE 19880 USA

sedimentation based processes are widely used in industry to separate particles from a liquid phase. Since the advent of the ＂Nanoworld＂ the demand for effective separation technologies has rapidly risen, calling for the development of new separation concepts, one of which lies in hybrid separation using the superposition of a magnetic field for magnetic particles. Possible product portfolio of such separation consists of pigment production, nanomagnetics production for electronics and bio separation, A promising step in that direction is magnetic field enhanced cake filtration, which has by now progressed from batch to continuous ooeration. In sedimentation processes in a mass force field the settling behaviour of particles strongly depends on physico-chemical properties, concentration and size distribution of the particles. By adjusting the pH, the interparticle forces, in particular the electrostatic repulsion, can be manipulated. For remanent magnetic particles such as magnetite, pre-treatment in a magnetic field could lead to a change of interparticle interactions. By magnetizing the particles apart from van der Waals attraction and electrostatic repulsion, an additional potential is induced, the magnetic attraction, which could easily dominate the other potentials and result in agglomeration in the primary minimum. By sedimentation analysis, a wide spectrum of parameters like pH, magnetic field strength and concentration have been investigated. The results show a strong increase of sedimentation velocity by magnetic flocculation of the raw suspension. This leads to a rise in throughput due to the acceleration of sedimentation kinetics by imparting a non-chemical interaction to the physico-chemical properties in the feed stream of the separation apparatus.

关键词： Magnetic flocculation Field enhanced separation Cake filtration Magnetic structuring Magnetic separation

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基于广义可扩展RPCA滤波的超快超声脑血流与功能成像方法研究

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仪器仪表学报 2024年第6期45卷 188-197页

作者：吴浩田闫少渊许凯亮他得安复旦大学生物医学工程系上海200438 复旦大学脑科学前沿科学中心上海200432 复旦大学集成芯片与系统全国重点实验室上海201203 上海波达医疗科技有限公司上海200433

开发高分辨和高灵敏度的小血管可视化技术,对相关组织病变的早期诊断和治疗监测具有重要的临床意义。不同于传统聚焦超声,超快超声多普勒(μDoppler)成像技术凭借数千帧的成像帧率,可检测到小血流的瞬时变化。组织杂波滤除和噪声抑制对... 详细信息

开发高分辨和高灵敏度的小血管可视化技术,对相关组织病变的早期诊断和治疗监测具有重要的临床意义。不同于传统聚焦超声,超快超声多普勒(μDoppler)成像技术凭借数千帧的成像帧率,可检测到小血流的瞬时变化。组织杂波滤除和噪声抑制对于μDoppler的成像质量至关重要。常用的杂波滤除方法为奇异值分解(SVD)方法,该方法利用信号时空相干性差异可快速实现组织杂波和血流信号分离,然而无法有效抑制噪声。本研究创新性提出了一种基于广义可扩展的鲁棒主成分分析(GSRPCA)的杂波滤除方法,使用Schatten p范数和lq范数来加强鲁棒主成分分析(RPCA)模型的低秩约束和稀疏约束,增强了小血流信号的提取能力。大鼠脑血流成像结果表明,GSRPCA能够提升功率多普勒成像中血管的成像质量,相较SVD提高信噪比约20 dB,且提高对比噪声比约10 dB。大鼠超声脑功能成像结果表明,GSRPCA能够提升小血管血容量动态检测的灵敏度。相关方法对超快超声成像杂波滤除的研究具有一定借鉴意义。

关键词：超快超声杂波滤除广义可扩展RPCA 脑血流功能成像

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Impact of chosen force fields and applied load on thin film lubrication

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Friction 2021年第5期9卷 1259-1274页

作者： Thi D.ta Hien D.ta Kiet A.TIEU Bach H.TRAN School of Mechanical MaterialsMechatronicsand Biomedical EngineeringUniversity of WollongongNSW 2522Australia Ho Chi Minh City University of Technology and Education Ho Chi Minh City 800010Vietnam

The rapid development of molecular dynamics(MD)simulations,as well as classical and reactive atomic potentials,has enabled tribologists to gain new insights into lubrication performance at the fundamental ***,the impact of adopted potentials on the rheological properties and tribological performance of hydrocarbons has not been researched *** extensive study analyzed the effects of surface structure,applied load,and force field(FF)on the thin film lubrication of *** lubricant film became more solid‐like as the applied load *** particular,with increasing applied load,there was an increase in the velocity slip,shear viscosity,and *** degree of ordering structure also changed with the applied load but rather *** was also significantly dependent on the surface *** chosen FFs significantly influenced the lubrication performance,rheological properties,and molecular *** adaptive intermolecular reactive empirical bond order(AIREBO)potential resulted in more significant liquid‐like behaviors,and the smallest velocity slip,degree of ordering structure,and shear stress were compared using the optimized potential for liquid simulations of united atoms(OPLS‐UAs),condensed‐phase optimized molecular potential for atomic simulation studies(COMPASS),and ***,classical potentials,such as OPLS‐UA and COMPASS,exhibit more solid‐like behavior than reactive potentials ***,owing to the solid‐like behavior,the lubricant temperatures obtained from OPLS‐UA and COMPASS were much lower than those obtained from AIREBO and *** increase in shear stress,as well as the decrease in velocity slip with an increase in the surface potential parameterζ,remained conserved for all chosen FFs,thus indicating that the proposed surface potential parameterζfor the COMPASS FF can be verified for a wide range of atomic models.

关键词： molecular dynamics simulation force fields applied load tribofilm hydrocarbon

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Challenges in determination of microscopic degree of cleanliness in ultra-clean gear steels

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Journal of Iron and Steel Research International 2022年第10期29卷 1583-1600页

作者： D.fuchs T.Tobie K.Stahl Gear Research Center(FZG) Technical University of Munich85748 GarchingGermany

Shot-peened,case-hardened gears can fail in the tooth root due to crack initiation below the surface of the steel ***,the crack is initiated at a non-metallic inclusion in the center of a so-called *** failure type can lead to a reduced endurance fatigue limit of the *** is for this reason that,over the last decade,much effort has been invested by steel manufacturers to reduce the non-metallic inclusion content of gear steels so as to mitigate or even completely prevent such crack *** ultra-clean gear steels were achieved by various measures in the steel production ***,as a result,the remaining non-metallic inclusions are inhomogeneously distributed in the steel volume in terms of both size and ***,due to the inhomogeneity of ultra-clean steels,the question arose if the values derived according to the standards are still representative of ultra-clean steel *** results show that the standards can still be applied,but more effort must be *** determine the degree of cleanliness,six microsections are currently evaluated according to steel test specification(seP)1571,method *** is shown that an examination of 24 microsections starting from size class 0 seems beneficial to get more reliable and comparable results of the degree of cleanliness of these ultra-clean gear *** addition,it is shown that a high degree of cleanliness has been achieved for all steel batches investigated with the measures taken in the steel production process.

关键词： Degree of cleanliness Non-metallic inclusion Evaluation of inclusion seP 1571 DIN 50602 Ultrasonic immersion testing Ultra-clean gear steel Gear

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Unit-cell design for two-dimensional phase-field simulation of microstructure evolution in single-crystal Ni-based superalloys during solidification

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Progress in Natural Science:Materials International 2017年第6期27卷 678-686页

作者： Dongjia Cao Na ta Lijun Zhang State Key Lab of Powder Metallurgy Central South University Interdisciplinary Centre for Advanced Materials Simulation (ICAMS) Ruhr-University Bochum

Phase-field simulation serves as an effective tool for quantitative characterization of microstructure evolution in single-crystal Ni-based superalloys during solidification nowadays. The classic unit cell is either limited to γdendrites along crystal orientation or too ideal to cover complex morphologies for γ dendrites. An attempt to design the unit cell for two-dimensional(2-D) phase-field simulations of microstructure evolution in single-crystal Ni-based superalloys during solidification was thus performed by using the MICRESS(MICRostructure Evolution Simulation Software) in the framework of the multi-phase-field(MPF) model,and demonstrated in a commercial TMS-113 superalloy. The coupling to CALPHAD(CALculation of PHAse Diagram) thermodynamic database was realized via the TQ interface and the experimental diffusion coefficients were utilized in the simulation. Firstly, the classic unit cell with a single γ dendrite along crystal orientation was employed for the phase-field simulation in order to reproduce the microstructure ***, such simple unit cell was extended into the cases with two other different crystal orientations, i.e., and . Thirdly, for crystal orientations, the effect of γ dendritic orientations and unit cell sizes on microstructure and microsegregation was comprehensively studied, from which a new unit cell with multiple γdendrites was proposed. The phase-field simulation with the newly proposed unit cell was further performed in the TMS-113 superalloy, and the microstructure features including the competitive growth of γ dendrites,microsegregation of different solutes and distribution of γ′ grains, can be nicely reproduced.

关键词： Ni-based superalloys Solidification Microstructure Phase-field simulation Unit cell

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A REMARK ON THE REGULARITY OF VECTOR-VALUED MAPPINGS DEPENDING ON TWO VARIABLES WHICH MINIMIZE SPLITTING-TYPE VARIATIONAL INTEGRALS

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Acta Mathematica Scientia 2010年第3期30卷 963-967页

作者： M. Bildhauer M. fuchs Universitt des Saarlandes Fachbereich 6.1 Mathematik

We combine the maximum principle for vector-valued mappings established by D＇Ottavio, Leonetti and Musciano [7] with regularity results from [5] and prove the Holder continuity of the first derivatives for local mini... 详细信息

关键词： Local minimizers interior regularity anisotropic energies two-dimensional problems

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提质培优背景下农类高职院校“双师型”教师队伍建设路径研究

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创新创业理论研究与实践 2024年第13期7卷 140-142页

作者：他淑君郑芳福建农业职业技术学院福建福州350000

提升高职院校教师“双师”素质是职业教育“三教”改革攻坚的必然要求,也是职业教育提质培优行动计划实施的重要内容。农类高职院校是培养“三农”发展所需技术技能型人才的重要基地,“双师型”教师队伍建设是培养高素质技术技能型人才... 详细信息

提升高职院校教师“双师”素质是职业教育“三教”改革攻坚的必然要求,也是职业教育提质培优行动计划实施的重要内容。农类高职院校是培养“三农”发展所需技术技能型人才的重要基地,“双师型”教师队伍建设是培养高素质技术技能型人才的关键。该文挖掘提质培优行动计划赋予农类高职院校“双师型”教师能力的新内涵,分析农类高职院校“双师型”教师队伍建设面临的问题,从3个方面提出农类高职院校“双师型”教师队伍建设策略,为进一步推动新阶段农类高职院校“双师型”教师队伍建设提供一定借鉴。

关键词：提质培优农类高职院校 “双师型”教师能力内涵困境建设路径

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Effects of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 on the peroxidase-catalyzed oxidation of 2-naphthol

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Journal of Environmental Sciences 2013年第7期25卷 1431-1440页

作者： Ivanec-Goranina Rūta Kulys Juozas Department of Chemistry and Bioengineering Faculty of Fundamental Sciences Vilnius Gediminas Technical University Institute of Biochemistry Vilnius University

The kinetics of the recombinant Coprinus cinereus peroxidase-catalyzed2-naphthol oxidationwas investigated in the presence of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 at pH 5.5 and25°C,with concentrations of （bio）surfactants both less than critical micelle concentrations （CMC） and larger than CMC. Itwas shown that monomers of JBR425 aswell as monomers of Surfynol465 had an enhancing effect on the conversion of2-naphthol indose response manner anddid not influence the initial rate of 2-naphthol oxidation. The resultswere accounted by a scheme,which contains a stadium of enzyme inhibition by oligomeric2- naphthol oxidation products. The action of the biosurfactant＇s （or synthetic surfactant＇s） monomerswas explained by avoidance of the enzyme active center clothingwith oligomers. Similar results havedemonstrated the potential of rhamnolipid biosurfactant JBR425due to its biodegradability. When biosurfactants＇ concentrations are larger than CMC, （bio）surfactants have an opposite effect on the oxidation of2-naphthol by peroxidase.

关键词： oxidation peroxidase biosurfactant critical micelle concentration

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恩沃单抗致皮肤系统不良反应的发生规律及特点

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中国新药杂志 2024年第12期33卷 1289-1296页

作者：凌彩色尹月林茂周歧骥张艳华北京大学肿瘤医院暨北京市肿瘤防治研究所药剂科恶性肿瘤发病机制及转化研究教育部重点实验室北京100142 右江民族医学院附属医院药学部百色533000 四川省肿瘤临床医学研究中心/四川省肿瘤医院研究所/四川省癌症防治中心/电子科技大学附属肿瘤医院药学部成都610041

目的:探讨恩沃单抗(enfortumab vedotin,EV)皮肤药物不良反应(cutaneous adverse drug reactions,CADR)的发生规律和临床表现特点,为临床安全合理用药提供参考。方法:检索中国知网、万方、维普、Pubmed和Web of Science等数据库收载的E... 详细信息

目的:探讨恩沃单抗(enfortumab vedotin,EV)皮肤药物不良反应(cutaneous adverse drug reactions,CADR)的发生规律和临床表现特点,为临床安全合理用药提供参考。方法:检索中国知网、万方、维普、Pubmed和Web of Science等数据库收载的EV相关CADR个案进行分析。结果:收集EV相关CADR个案报道15篇,共30例患者,其中男性28例,女性2例,年龄分布在59~78岁,CADR发生于用药后1~44 d。对于11例确诊中毒性表皮坏死综合征(Stevens-Johnson syndrome,SJS)或中毒性表皮坏死(toxic epidermal necrolysis,TEN)患者,主要病理特点是大量角化细胞坏死或凋亡,临床表现为全身大面积红斑及大疱,并累及口腔、眼睛、鼻子、生殖器等黏膜。而对于其他19例CADR患者,其临床表现和病理特点差异较大且不典型,严重者与SJS/TEN相似,而对于某些CADR较轻的患者仅表现为全身瘙痒伴皮疹。糖皮质激素是目前用于治疗EV引起CADR的主要药物,但是总体效果不佳,经治疗后仍有13例患者(43.3%)发生死亡。结论:临床应加强对EV引起CADR的认识和监测,及时诊断与治疗,确保用药安全。

关键词：恩沃单抗皮肤药物不良反应文献分析

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结合数据增强方法的藏文预训练语言模型

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中文信息学报 2024年第9期38卷 66-72页

作者：色差甲班马宝才让加柔特省部共建藏语智能信息处理及应用国家重点实验室青海西宁810008 青海省藏文信息处理工程技术研究中心青海西宁810008

最近在自然语言处理领域中,预训练加微调模式已然成为新的训练范式。在藏文自然语言处理领域中虽缺乏人工标注数据,但预训练语言模型能够缓解下游任务中数据规模不足和模型重新训练时难以收敛等问题。首先,该文收集整理含有46.55亿字符... 详细信息

最近在自然语言处理领域中,预训练加微调模式已然成为新的训练范式。在藏文自然语言处理领域中虽缺乏人工标注数据,但预训练语言模型能够缓解下游任务中数据规模不足和模型重新训练时难以收敛等问题。首先,该文收集整理含有46.55亿字符的藏文文本语料;然后在UniLM模型的基础上,利用藏文文本特征的数据增强方法和预训练技术相结合的方法预训练藏文语言模型。实验表明,该文方法在藏文La格例句分类和藏文文本分类等四个下游任务中获得显著效果。

关键词：藏文预训练语言模型文本数据增强方法 UniLM模型

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