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magnetic properties and microstructures of SnO_2 doped mn-Zn ferrites

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Rare metals 2006年第z1期25卷 445-449页

作者： NG Foong-Kee SALE frank R. School of Technology Tunku Abdul Rahman College PO Box 10979 50932 Kuala Lumpur West Malaysia School of materials The University of Manchester Grosvenor Street Manchester M17HS United Kingdom

The effects of additive SnO2 (0.4wt.%), with and without SiO2 (0.02wt.%) and/or CaO (0.04wt.%), on the microstructure and magnetic properties of mn-Zn ferrites were reported. The results reveal that SnO2 on its own increases the initial permeability (μi) slightly, but SnO2 with SiO2 and/or CaO decreases the values of μi. However, ferrites with SnO2 additions have reduced power losses. The separate contributions of hysteresis loss and eddy current loss to the total power loss show that SnO2 (with or without SiO2 and/or CaO) doping increases the hysteresis loss slightly, but SnO2 doping alone reduces the eddy current loss significantly (～14%). The additions of SiO2 or CaO further decrease the eddy current loss, and by interaction of SnO2-CaO-SiO2, the eddy current loss is reduced by more than 20%. These magnetic and microstructural effects were discussed in terms of the additive-impurity interaction, the existence of grain boundary phases, and the effective bulk and grain boundary resistivities of the ferrites.

关键词： mn-Zn ferrites SnO2 doping magnetic properties microstructure

Electronic structure factors and the importance of adsorbate effects in chemisorption on surface alloys

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npj Computational materials 2022年第1期8卷 1560-1571页

作者： Shikha Saini Joakim Halldin Stenlid frank Abild-Pedersen SUNCAT Center for Interface Science and Catalysis Department of Chemical EngineeringStanford University443 Via OrtegaStanfordCA94305USA SUNCAT Center for Interface Science and Catalysis SLAC National Accelerator Laboratory2575 Sand Hill RoadMenlo ParkCA94025USA

The chemisorption energy is an integral aspect of surface chemistry,central to numerous fields such as catalysis,corrosion,and ***-structure-based methods such as the Newns-Anderson model are therefore of great importance in guiding the engineering of material surfaces with optimal ***,existing methods are inadequate for interpreting complex,multi-metallic ***,we introduce a physics-based chemisorption model for alloyed transition metal surfaces employing primarily metal d-band properties that accounts for perturbations in both the substrate and adsorbate electronic states upon ***,we show that adsorbate-induced changes in the adsorption site interact with its chemical environment leading to a second-order response in chemisorption energy with the d-filling of the neighboring *** demonstrate the robustness of the model on a wide range of transition metal alloys with O,N,CH,and Li adsorbates yielding a mean absolute error of 0.13 eV versus density functional theory reference chemisorption energies.

关键词： alloys corrosion chemisorption

Fluid mechanics / frank m. White. 4th ed.

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Fluid mechanics / Frank M. White.

Breakthrough in the challenging P450-catalyzed chemoenzymatic synthesis of C14-functionalized steroids

1999年

作者： frank m. White.

来源：畅想之星图书光盘版（南... 评论

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中国科学:化学英文版 2023年第9期66卷 2435-2436页

作者： manfred T.Reetz frank Hollmann max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 145480 MülheimGermany Tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjin 300308China Department of Biotechnology Delft Universityvan der Maasweg 92629 HZ DelftNetherlands

Intensive past research has demonstrated that cytochrome P450 monooxygenases are involved in the biosynthesis of numerous natural products and in human metabolism of various pharmaceuticals [1]. This inspired synthetic organic and pharmaceutical chemists to test them as catalysts in the oxidative hydroxylation of steroids. Unfortunately, wildtype P450s generally proved to show low levels of regio-and diastereoselectivity as well as suboptimal activity.

关键词： steroids catalyzed synthesis

Lead-free molecular one-dimensional perovskite for efficient X-ray detection

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Journal of Energy Chemistry 2022年第1期31卷 209-213,I0007页

作者： Haojin Li Xin song Chuang ma Zhuo Xu Nuo Bu Tinghuan Yang Qingyue Cui Lili Gao Zhou Yang Fei Gao Guangtao Zhao Zhaolai Chen Zicheng Ding Kui Zhao Shengzhong(frank)Liu Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationShaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologyInstitute for Advanced Energy MaterialsSchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an 710119ShaanxiChina Dalian National Laboratory for Clean Energy iChEMDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Department of Chemical Physics Collaborative Innovation Center of Chemistry for Energy Materials(iChEM)University of Science and Technology of ChinaHefei 230026AnhuiChina State Key Laboratory of Crystal materials Institute of Crystal MaterialsShandong UniversityJinan 250100ShandongChina

In recent years,great progress has been achieved for organicinorganic halide perovskites due to their excellent optoelectronic properties and stability for photovoltaics,light emitting diodes,and high-energy radiation detection[1-5].One-dimensional(1D)perovskites,as an important derivative of three-dimensional(3D)perovskites,exhibit low exciton dissociation efficiency,which can produce strong quantum confinement and form self-trapping excited state[6],In addition,the hydrophobic properties and the inhibition of ion migration from large organic cations improve the moisture and thermal stability for optoelectronic devices.

关键词： Perovskite molecular one-dimensional perovskite X-ray detection Self-trapped emission

An Optical Pressure Sensor Based on mEmS

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稀有金属材料与工程 2006年第S3期 476-478页

作者： frank Lewis TX 76019 The University of Texas at Arlington Arlington USA

An optical fiber pressure sensor has been developed for the measurement in human *** sensing element is possessed of a membrane structure,which is fabricated by *** fabrication process includes anisotropic wet etching on the silicon *** the transmitting source and signal light,a multimode optical fiber 50/125 μm (core/clad)in diameter was *** intensity of the light reflected back into the fiber varies with the membrane deflection,which is s function of *** deflection of the membrane by applied pressure can be mathematically described.

关键词： optical fiber pressure sensor mEmS

Spatially resolved and multiplexed microRNA quantification from tissue using nanoliter well arrays

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microsystems & Nanoengineering 2020年第1期6卷 1007-1015页

作者： maxwell B.Nagarajan Augusto m.Tentori Wen Cai Zhang frank J.Slack Patrick S.Doyle Department of Chemical Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA HmS Initiative for RNA medicine Department of PathologyHarvard Medical SchoolBeth Israel Deaconess Medical CenterBostonMA 02215USA

Spatially resolved gene expression patterns are emerging as a key component of medical studies,including companion diagnostics,but technologies for quantification and multiplexing are *** present a method to perform spatially resolved and multiplexed microRNA(miRNA)measurements from formalin-fixed,paraffin-embedded(FFPE)*** nanoliter well arrays to pixelate the tissue section and photopatterned hydrogels to quantify miRNA,we identified differentially expressed miRNAs in tumors from a genetically engineered mouse model for non-small cell lung cancer(K-ras&(LSL-G12D/+);p53^(fl/fl)).This technology could be used to quantify heterogeneities in tissue samples and lead to informed,biomarker-based diagnostics.

关键词： resolved Spatial lung

Changes in higher order aberrations after central corneal regularization-a comparative two-year analysis of a semiautomated topography-guided photorefractive keratectomy combined with corneal cross-linking

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Eye and Vision 2020年第1期7卷 99-108页

作者： Katja C.Iselin Philipp B.Baenninger Lucas m.Bachmann frank Bochmann michael A.Thiel Claude Kaufmann Department of Ophthalmology Lucerne Cantonal HospitalLucerneSwitzerland medignition Healthcare Innovations ZurichSwitzerland

Background:The optical quality in progressive keratoconus deteriorates due to ectasia and distortion of the corneal shape and *** corneal cross-linking(CXL)aims at stopping disease progression,“CXL-Plus”combines CXL with excimer laser ablation to improve visual *** Corneal Regularization(CCR)represents a therapeutic excimer laser modality specifically designed to smoothen the ectatic corneal shape and to reduce higher order aberrations(HOA).We set out to compare CXL-Plus,consisting of CXL combined with CCR,with CXL by itself for patients with progressive ***:Retrospective 2-year matched group analysis of patients who either underwent CXL-Plus(n=28)or CXL as a sole procedure(n=28)for progressive *** outcome parameters were HOA,visual function and tomographic results 12 and 24 months ***:After 12 months,the total HOA root mean square wavefront error was reduced from 0.79±0.30 to 0.40±0.19μm(CXL-Plus;pm 0.71±0.28 to 0.73±0.36μm(CXL;p=0.814).Uncorrected distance visual acuity improved from 0.70±0.35 to 0.36±0.29 logmAR(CXL-Plus;p=0.0002)and from 0.65±0.39 to 0.46±0.37 logmAR(CXL;p=0.067),translating to gains of three or more lines in 50%(CXL-Plus)and 36%(CXL)of *** steepest keratometry value(Kmax)regressed by 5.84 D(CXL-Plus;pmeters a statistically significant change could be shown between 12 and 24 ***:CXL-Plus in the form of a CCR reduces HOA and Kmax more effectively than CXL as a sole procedure.

关键词： Keratoconus Corneal cross-linking CXL-plus Photorefractive keratectomy Central corneal regularization Higher order aberrations Coma-like aberrations

model reference adaptive impedance control for physical human-robot interaction

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Control Theory and Technology 2016年第1期14卷 68-82页

作者： Bakur ALQAUDI Hamidreza mODARES Isura RANATUNGA Shaikh m. TOUSIF frank L. LEWIS Dan O. POPA The University of Texas at Arlington Research Institute (UTARI) Fort Worth TX 76118 U.S.A. Department of Electrical Engineering College of Engineering The University of Texas at Arlington Arlington TX 76019 U.S.A. Electronics and Instrumentation Engineering Technology Department Yanbu Industrial College P.O. Box 30436 41912 Yanbu al-Sinaiyah K.S.A. State Key Laboratory of Synthetical Automation for Process Industries Northeastern University Shenyang Liaoning 110819 China

This paper presents a novel enhanced human-robot interaction system based on model reference adaptive control. The presented method delivers guaranteed stability and task performance and has two control loops. A robot-specific inner loop, which is a neuroadaptive controller, learns the robot dynamics online and makes the robot respond like a prescribed impedance model. This loop uses no task information, including no prescribed trajectory. A task-specific outer loop takes into account the human operator dynamics and adapts the prescribed robot impedance model so that the combined human-robot system has desirable characteristics for task performance. This design is based on model reference adaptive control, but of a nonstandard form. The net result is a controller with both adaptive impedance characteristics and assistive inputs that augment the human operator to provide improved task performance of the human-robot team. Simulations verify the performance of the proposed controller in a repetitive point-to-point motion task. Actual experimental implementations on a PR2 robot further corroborate the effectiveness of the approach.

关键词： Human-robot interaction model reference adaptive control model reference neuroadaptive impedance control