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Searching for ductile superconducting Heusler X_(2)YZ compounds

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npj Computational Materials 2023年第1期9卷 919-927页

作者： Noah Hoffmann Tiago F.T.Cerqueira Pedro Borlido Antonio Sanna Jonathan Schmidt Miguel A.l.Marques Institut für Physik Martin-Luther-Universität Halle-WittenbergD-06099 HalleGermany CFisUC Department of PhysicsUniversity of CoimbraRua Larga 3004-516 CoimbraPortugal Max-Planck-Institut für Mikrostrukturphysik Weinberg 2D-06120 HalleGermany

Heusler compounds attract a great deal of attention from researchers thanks to a wealth of interesting properties,among which is *** we perform an extensive study of the superconducting and elastic properties of the cubic(full-)Heusler family using a mixture of ab initio methods,as well as interpretable and predictive machine-learning *** analyzing the statistical distributions of these properties and comparing them to anti-perovskites,we recognize universal behaviors that should be common to all conventional superconductors while others turn out to be specific to the material *** total,we discover a total of eight hypothetical materials with critical temperatures above 10 K to be compared with the current record of T_(c)=4.7 K in this ***,we expect most of these materials to be highly ductile,making them potential candidates for the manufacture of wires and tapes for superconducting magnets.

关键词： ductile compounds superconducting

Transesterification of sunflower oil in microchannels with circular obstructions

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Chinese Journal of Chemical Engineering 2018年第4期26卷 852-863页

作者： Harrson S.Santana Joao l.Silva Jr Deborah S.Tortola Osvaldir P.Taranto School of Chemical Engineering University of Campinas13083-852 CampinasSPBrazil Federal Institute of Education Science and Technology of South of Minas Gerais-IFSULDEMINAS37560-260 Poaso AlegreMGBrazil

The present paper studied numerical and experimentally the transesterification reaction between sunflower oil and ethanol with NaO H catalyst in microchannels with circular obstructions. The micromixer design influence on fluid mixing and oil conversion was investigated for a range of operating conditions: Reynolds number(Re = 0.1–100),Temperature(25–75 °C), ethanol/oil molar ratio(6-12), and catalyst concentration(0.75 wt%–1.25 wt%), using three microchannel configurations(length = 35 mm; Width = 1500 μm; Height = 200 μm): T-shape – channel without obstructions; MCO – channel with 3 obstructions ensemble – equally disposed over longitudinal length;MWO – channel with 7 obstructions ensemble. The MCO micromixer was based on literature work, and the MWO is a totally new micromixer design. Experimental tests were conducted in similar conditions in microreactors using these micromixers(length = 411 mm) made of polydimethylsiloxane. The MCO configuration presented the highest performance(mixing index of 0.80 at Re = 100), oil conversion of 81.13% at 75 °C, molar ratio of 9 and catalyst concentration of 1%. Experimental results showed high conversions for MCO and MWO configurations(99.99%) at 50 °C, molar ratio of 9 and catalyst concentration of 1%, with a residence time of 12 s.

关键词： Biodiesel Sunflower oil-ethanol Transesterification reaction Circular obstructions Microreactor Numerical simulation

Delayed Ionization and Delayed Detachment in Molecules and Clusters

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Chinese Journal of Chemical Physics 2009年第2期22卷 162-170页

作者： F. lépine B. Baguenard B. Concina M. A. lebeault C. Bordas Université de lyon F-69522 Lyon France Université lyon 1 Villeurbanne CNRS UMR 5579 LASIM

The evolution of a molecular system excited above its ionization threshold depends on a number of parameters that include the nature of the excited states and their couplings to the various continua. The general nature of the processes governing this evolution depends also essentially on the complexity of the molecule, more precisely on its size, density of states, and strength of the couplings among the various internal degrees of freedom. In this paper we address the question of the transition between autoionization that prevails in small molecules, and delayed ionization occurring in larger molecules or clusters. This transition is illustrated by autoionization of Na2 Rydberg states on one hand, delayed ionization in fullerene C60, and delayed detachment in small cluster anions on the other hand. All processes are studied in the case of nanosecond laser excitation, corresponding to a rather slow deposition of the internal energy.

关键词： Autoionization Autodetachment Thermionic emission

应用衰减全反射红外光谱无损鉴别中国传统手工纸的方法研究

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光谱学与光谱分析 2024年第9期44卷 2450-2458页

作者：吕淑贤北京大学图书馆北京100871

纤维种类鉴别是古代纸张保护的重要基础工作。探究中国传统手工纸的无损纤维鉴别的方法对中国古籍、档案及纸质文物的研究和保护具有重要意义。该研究应用衰减全反射傅里叶变换红外光谱(ATRFTIR)对已知纤维成分的17类64种中国传统手工... 详细信息

纤维种类鉴别是古代纸张保护的重要基础工作。探究中国传统手工纸的无损纤维鉴别的方法对中国古籍、档案及纸质文物的研究和保护具有重要意义。该研究应用衰减全反射傅里叶变换红外光谱(ATRFTIR)对已知纤维成分的17类64种中国传统手工纸标准样品进行了无损分析,参考纤维素和木质素的红外峰位及部分纸样的X射线衍射(XRD)分析结果确认纸样中的所有红外谱峰归属;并采用分波段比较分析的方法对相似度极高的谱图进行比对分析,分别总结各类纸张在4000~1800、1800~1500、1500~1200和1200~600cm^(-1)四个波段的谱图特征;同时对4cm^(-1)精度的谱图进行二阶导数处理,分别总结各类纸张在1500~1200和1200~900cm^(-1)两个波段的二阶导数谱图特征;最后通过红外结晶指数及其他峰高和峰面积比值计算结果实现对纸类更细致的区分。应用上述方法对16个盲测样品进行了有效性测试,红外分析结果与显微纤维鉴别结果一致,初步证明了该方法在中国传统手工纸无损纤维鉴别上的可行性和有效性。实验结果表明,应用ATR-FTIR无损分析法可对麻、桑构皮、檀皮、瑞香皮和竹几大类原料的传统手工纸纤维类型作出快速而准确的鉴别,对于混料的宣纸也同样适用;但对于显微分析也难以鉴别的亲缘关系较近的植物原料如桑、构皮之间的精细鉴别仍有一定局限性。

关键词：衰减全反射傅里叶变换红外光谱二阶导数红外光谱中国传统手工纸纤维鉴别无损分析

Bariatric surgery in patients with non-alcoholic fatty liver disease-from pathophysiology to clinical effects

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World Journal of Hepatology 2019年第2期11卷 138-149页

作者： Tea l laursen Christoffer A Hagemann Chunshan Wei Konstantin Kazankov Karen l Thomsen Filip K Knop Henning Grønbæk Department of Hepatology and Gastroenterology Aarhus University Hospital Gubra ApS Clinical Metabolic Physiology Steno Diabetes Center CopenhagenGentofte Hospital Department of Clinical Medicine Faculty of Health and Medical SciencesUniversity of Copenhagen Department of Hepatology Shenzhen Traditional Chinese Medicine Hospitalthe Fourth Clinical Medical College of Guangzhou University of Chinese Medicine Novo Nordisk Foundation Center for Basic Metabolic Research Faculty of Health and Medical SciencesUniversity of Copenhagen

Non-alcoholic fatty liver disease(NAFlD) is increasingly recognized as a significant liver disease,and it covers the disease spectrum from simple steatosis with a risk of development of non-alcoholic steatohepatitis(NASH) to fibrosis,subsequent cirrhosis,end-stage liver failure,and liver cancer with a potential need for liver *** and NASH are closely related to obesity,metabolic syndrome,and type 2 diabetes(T2 D).The role of gut hormones,especially glucagon-like peptide 1(GlP-1),is important in *** surgery has the potential for inducing great weight loss and may improve the symptoms of metabolic syndrome and T2 *** data demonstrated significant effects of bariatric surgery on GlP-1 and other gut hormones and important lipid metabolic and inflammatory abnormalities in the pathophysiology of ***,bariatric surgery may reverse the pathological liver changes in NAFlD and NASH *** the present review,we describe NAFlD and NASH pathophysiology and the primary effects of bariatric surgery on metabolic *** performed a systematic review of the beneficial and harmful effects and focused on changes in liver disease severity in NAFlD and NASH *** specific focus was liver histopathology as assessed by the invasive liver ***,we reviewed several non-invasive methods used for the assessment of liver disease severity following bariatric surgery.

关键词： Non-alcoholic fatty liver disease Non-alcoholic steatohepatitis Bariatric surgery Insulin resistance,Gut hormones Glucagon-like peptide 1 Steatosis Inflammation Fibrosis

Development of a field enhanced photocatalytic device for biocide of coliform bacteria

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Journal of Environmental Sciences 2016年第6期28卷 38-44页

作者： Jeff M.Huber Krista l.Carlson Otakuye Conroy-Ben Mano Misra Swomitra K.Mohanty Departments of Civil Engineering University of Utah Departments of Metallurgical Engineering University of Utah Departments of Chemical Engineering University of Utah

A field enhanced flow reactor using bias assisted photocatalysis was developed for bacterial disinfection in lab-synthesized and natural waters. The reactor provided complete inactivation of contaminated waters with flow rates of 50 ml/min. The device consisted of titanium dioxide nanotube arrays, with an externally applied bias of up to 6 V. light intensity, applied voltage, background electrolytes and bacteria concentration were all found to impact the device performance. Complete inactivation of Escherichia coli W3110（- 8 × 10^3CFU/ml） occurred in 15 sec in the reactor irradiated at 25 mW/cm^2 with an applied voltage of 4 V in a 100 ppm NaCl solution. Real world testing was conducted using source water from Emigration Creek in Salt lake City, Utah. Disinfection of natural creek water proved more challenging, providing complete bacterial inactivation after 25 sec at 6 V. A reduction in bactericidal efficacy was attributed to the presence of inorganic and organic species, as well as the increase in robustness of natural bacteria.

关键词： Titanium dioxide Nanotubes Immobilized Photocatalysis Escherichia coli Inactivation

Corrosion protection investigations of carbon dots and polydopamine composite coating on magnesium alloy

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Journal of Magnesium and Alloys 2022年第5期10卷 1358-1367页

作者： H.D.Zhang A.Y.Chen B.Gan H.Jiang l.J.Gu School of Material Science&Engineering University of Shanghai for Science and TechnologyShanghai 200093China Beijing Key laboratory of Advanced High Temperature Materials Central Iron and Steel Research InstituteBeijing 100081China

A composite coating of nitrogen-doped carbon dots(N–CDs)and polydopamine(PDA)was prepared on magnesium alloy by combining electrodeposition with dip coating *** microstructure of the N–CDs/PDA composite coating,including composition,surface morphology,and crystalline structure,is characterized by Raman spectroscopy,scanning electron microscopy,transmission electron microscopy,and X-ray photoelectron spectroscopy,*** corrosion protection performances of the composite coating are evaluated by potentiodynamic polarization tests,electrochemical impedance spectroscopy,and salt spray *** effect of the particle size of the N–CDs on the corrosion performance is also *** results show that the corrosion performance of the N–CDs coatings are enhanced with the increase of the particle ***,an obvious self-healing performance is observed on the surface of the N–CDs/PDA composite *** results indicate that N–CDs/PDA composite coating can improve the corrosion performance of the Mg alloy,and open a new design direction for the protective coating of metallic materials.

关键词： Magnesium alloy N-doped carbon dots Particle size Dopamine Coating Corrosion resistance

DFT Study of Iron Tetraphenylporphyrin Chloride and Iron Pentafluorophenylporphyrin Chloride

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Chinese Journal of Chemical Physics 2006年第3期19卷 227-232页

作者： Qing-zhang lü Yan lu Jian-ji Wang College of Chemistry and Environmental Sciences Henan Normal University Xinxiang 453007 China

The geometry optimizations and the single point energy calculations of iron tetraphenylporphyrin chloride Fe（TPP）Cl and iron tetraphenylporphyrin chloride （Fe（TPP）Cl）, iron pentafluorophenylporphyrin chloride （Fe（TPPF20）Cl） were carried out by using the Density Functional Theory （DFT） UB3lYP with STO-3G^＊ and 6-31G^＊ basis sets, respectively. The electronic properties and the structures of high-lying molecular orbitals were analyzed in detail. The results show that partial spin is transferred from the Fe atom to the porphyrin ring and some electron with the spin opposite to the unpaired electron on the Fe atom is transferred from the porphyrin ring to the Fe atom. The π and σ-type bonding between the Fe atom and the porphyin ring cause the transfer. The fluorination enhances the electron transfer and the chemical stability of the complex. The high stability is important for the complex possessing high catalytic activity. The catalysis mechanism of oxygen molecule activation on the complex surface is also discussed based on the symmetry of the molecular orbitals.

关键词： Iron porphyrin DFT Molecular orbital Activation mechanism of molecular oxygen

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新移动出行时代,影响未来五年的关键课题

汽车与配件 2020年第8期 26-27页

作者： David Bishop Ashish Khanna 王怿凯 Christophe ruiz l.E.K.咨询

汉莎航空创新中心的报告显示,目前在移动出行领域活跃的初创企业有2500家,其中,22家领先企业的总估值高达2300亿美元。正在市场中流通的电动汽车数量高达数百万辆,款式超过150种。在开展相关工作时,l.E.K.咨询强调移动出行领域中的六大... 详细信息

汉莎航空创新中心的报告显示,目前在移动出行领域活跃的初创企业有2500家,其中,22家领先企业的总估值高达2300亿美元。正在市场中流通的电动汽车数量高达数百万辆,款式超过150种。在开展相关工作时,l.E.K.咨询强调移动出行领域中的六大颠覆性趋势(图1),这些趋势互联互通,它们将共同为移动出行生态系统带来彻底的改变。这些颠覆性趋势引发了五个关键的系统性问题,而它们将决定移动出行作为一种经济系统和社会基础设施在未来五年甚至更长远的发展方向。

关键词：移动出行社会基础设施初创企业领先企业电动汽车生态系统互联互通未来五年