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Entangled photons enabled ultrafast stimulated Raman spectroscopy for molecular dynamics

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Light(Science & Applications) 2024年第8期13卷 1615-1622页

作者： Jiahao joel Fan Zhe-Yu Ou Zhedong Zhang Department of Physics City University of Hong KongKowloonHong Kong SARChina City University of Hong Kong Shenzhen Research InstituteShenzhenGuangdongChina

Quantum entanglement has emerged as a great resource for studying the interactions between molecules and *** propose a new scheme of stimulated Raman scattering with entangled photons.A quantum ultrafast Raman spectroscopy is developed for condensed-phase molecules,to monitor the exciton populations and *** results are obtained,showing an entanglement-enabled time-frequency scale not attainable by classical *** Raman signal presents an unprecedented selectivity of molecular correlation functions,as a result of the Hong-Ou-Mandel *** work suggests a new paradigm of using an unconventional interferometer as part of spectroscopy,with the potential to unveil advanced information about complex materials.

关键词： materials spectroscopy selectivity

Additive manufacturing of 18%nickel maraging steels:Defect,structure and mechanical properties:A review

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Journal of Materials Science & Technology 2022年第25期120卷 227-252页

作者： Lulu Guo Lina Zhang joel Andersson Olanrewaju Ojo Department of Mechanical Engineering University of ManitobaWinnipeg R3T 5V6Canada Department of Engineering Science University WestTrollh tan 46186Sweden

This paper reviews the latest research progress in the additive manufacturing(AM)process of 18%nickel maraging steels,which involves laser-based powder bed fusion(L-PBF),laser-based directed energy deposition(L-DED),and wire arc additive manufacturing(WAAM).The emphasis is on the defects,structure,and mechanical properties of the additive manufactured 18%nickel maraging *** first,this article outlines the influences of the processing parameters of AM techniques on the defects formed in the fabricated parts,in terms of the L-PBF and *** macrostructure and microstructure characteristics of as-built and heat-treated 18%nickel maraging steel are then described in ***,the mechanical properties of as-built and heat-treated 18%nickel maraging steel are assessed,such as their tensile,hardness,impact toughness,and fatigue ***,future directions for work on the AM of 18%nickel maraging steel are provided.

关键词： Additive manufacturing 18%Nickel maraging steel Defects Macrostructure Microstructure Mechanical properties

Quasinormal modes of a Schwarzschild black hole immersed in an electromagnetic universe

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Chinese Physics C 2018年第10期42卷 160-166页

作者： Ali Ovgiin Izzet Sakalh joel Saavedra Instituto de Fisica Pontificia Universidad Catdlica de Valparai soCasilla 4950ValparaisoChile Physics Department Arts and Sciences FacultyEastern Mediterranean UniversityFamagustaNorth Cyprus via Mersin 10Turkey School of Natural Sciences Institute for Advanced Study1 Einstein DrivePrincetonNJ 08540USA

We study the quasinormal modes （QNMs） of a Schwarzschild black hole immersed in an electromagnetic （EM） universe. The immersed Schwarzschild black hole （ISBH） originates from the metric of colliding EM waves with double polarization [Class. Quantum Grav. 12, 3013 （1995）]. The perturbation equations of the scalar fields for the ISBH geometry are written in the form of separable equations. We show that these equations can be transformed to the confluent Heun＇s equations, for which we are able to use known techniques to perform analytical quasinormal （QNM） analysis of the solutions. Furthermore, we employ numerical methods （Mashhoon and 6^th-order Wentzel- Kramers-Brillouin （WKB）） to derive the QNMs. The results obtained are discussed and depicted with the appropriate plots.

关键词： quasinormal modes scalar particles Schwarzschild electromagnetic universe wave scattering heun functions

The Life-cycle Dynamics of Zombie Companies amongst Listed Firms in China

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China & World Economy 2022年第5期30卷 185-205页

作者： joel Bowman Crawford School of Public Policy Australian National UniversityAustralia

This paper analyses the life-cycle dynamics of zombie companies-broadly defined as businesses that are consistently unable to meet their interest expenses from current profits-amongst listed firms in China over the period 2008-2019.A large share of zombie companies subsequently return to nonzombie *** proportion is higher for firms undergoing a major restructuring event,low leverage levels,and with smaller operating expense ***,zombie firms that return to nonzombie status continue to have lower levels of profitability compared with their industry peers and have a higher probability of relapsing into zombie status compared with firms that have never been classified as *** efforts to revive zombie companies using major restructuring events appear insufficient in overcoming the longer term scarring effects of zombification on firms'*** results highlight the potential benefits of the ongoing efforts by Chinese regulators to improve the delisting process.

关键词： China laggards survival analysis zombie companies

Mechanism and kinetics of hydrothermal replacement of magnetite by hematite

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Geoscience Frontiers 2019年第1期10卷 29-41页

作者： Jing Zhao joel Brugger Allan Pring Chemical and Physical Science College of Science and Engineering Flinders University School of Earth Atmosphere and the Environment Monash University

The replacement of magnetite by hematite was studied through a series of experiments under mild hydrothermal conditions(140 -220℃, vapour saturated pressures) to quantify the kinetics of the transformation and the relative effects of redox and non-redox processes on the transformation. The results indicate that oxygen is not an essential factor in the replacement reaction of magnetite by hematite, but the addition of excess oxidant does trigger the oxidation reaction, and increases the kinetics of the transformation. However, even under high O_2(aq) environments, some of the replacement still occurred via Fe^(2+) leaching from magnetite. The kinetics of the replacement reaction depends upon temperature and solution parameters such as pH and the concentrations of ligands, all of which are factors that control the solubility of magnetite and affect the transport of Fe^(2+) (and the oxidant) to and from the reaction front. Reaction rates are fast at ~200℃, and in nature transport properties of Fe and,in the case of the redox-controlled replacement, the oxidant will be the rate-limiting control on the reaction progress. Using an Avrami treatment of the kinetic data and the Arrhenius equation, the activation energy for the transformation under non-redox conditions was calculated to be 26 ± 6 kJ mol^(-1).This value is in agreement with the reported activation energy for the dissolution of magnetite, which is the rate-limiting process for the transformation under non-redox conditions.

关键词： Mineral replacement reaction Hematite Magnetite Kinetics Non-redox Redox

Epididymis cholesterol homeostasis and sperm fertilizing ability

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Asian Journal of Andrology 2011年第1期13卷 11-17页

作者： Fabrice Saez Ouvrier and joel R Drevet UMR GReD CNRS 6247 INSERM U931 Clermont Universite Equipe ＇Epididyme et maturation des gametes＇ Aubiere cedex 63171 France

Cholesterol, being the starting point of steroid hormone synthesis, is a long known modulator of both female and male reproductive physiology especially at the level of the gonads and the impact cholesterol has on gametogenesis. Less is known about the effects cholesterol homeostasis may have on postgonadic reproductive functions. Lately, several data have been reported showing how imbalanced cholesterol levels may particularly affect the post-testicular events of sperm maturation that lead to fully fertile male gametes. This review will focus on that aspect and essentially centers on how cholesterol is important for the physiology of the mammalian epididymis and spermatozoa.

关键词： cholesterol homeostasis epididymosomes fertility post-testicular maturation spermatozoa

Influence of the Iron Anisothermal Sintering on the Characteristic of the Hollow Cathode Discharge

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材料热处理学报 2004年第5期25卷 83-87页

作者： BRUNATTO Silvio Francisco MUZART joel Louis Rene Department of Mechanical Engineering UFPR 81531-990 Curitiba-PR BrazilDepartment of Mechanical Engineering UFSC 88040-900 Florianopolis-SC Brazil

This work studies the influence of anisothermal iron sintering process on hollow cathode discharge characteristics. Two independent cathodes form an annular discharge. The pressed cylindrical iron powder sample, acting as central cathode, was placed concentrically in the interior of an external cathode. The external cathode, machined from an AISI 310 steel bar, besides acting to confine the geometry of the plasma, can also acts as a source of alloying elements. The sample heating is a function of the ion bombardment energy and, so, of the discharge electrical parameters: current (or current density) and the effective potential applied to the cathode. Successive anisothermal sintering is performed in a same sample until the reproducibility of the electrical parameters being obtained. The heating experiments up to 1250 °C, in a gas mixture of 80% Ar + 20% H2, at pressure of 133 Pa, at flow of 2xlO"6 mV, with an inter-cathode radial space of 5.8 mm, were carried out. It was verified the metallurgical evolution of the iron sample sintering process influences the current-?0n (time switched-on of the pulse) characteristics of the discharge.

关键词：空心阴极放电等离子体焊结烧结铁溅射非等温焙烧

Heavy-organic particle deposition from petroleum fluid flow in oil wells and pipelines

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Petroleum Science 2010年第4期7卷 502-508页

作者： joel Escobedo G.Ali Mansoori University of Illinois at Chicago 851 S. Morgan St. (M/C 063) Chicago IL 60607-7052 USA

Suspended asphaltenic heavy organic particles in petroleum fluids may stick to the inner walls of oil wells and pipelines. This is the major reason for fouling and arterial blockage in the petroleum industry. This report is devoted the study of the mechanism of migration of suspended heavy organic particles towards the walls in oil-producing wells and pipelines. In this report we present a detailed analytical model for the heavy organics suspended particle deposition coefficient corresponding to petroleum fluids flow production conditions in oil wells. We predict the rate of particle deposition during various turbulent flow regimes. The turbulent boundary layer theory and the concepts of mass transfer are utilized to model and calculate the particle deposition rates on the walls of flowing conduits. The developed model accounts for the eddy diffusivity, and Brownian diffusivity as well as for inertial effects. The analysis presented in this paper shows that rates of particle deposition （during petroleum fluid production） on the walls of the flowing channel due solely to diffusion effects are small. It is also shown that deposition rates decrease with increasing particle size. However, when the process is momentum controlled （large particle sizes） higher deposition rates are expected.

关键词： Asphaltene Brownian deposition coefficient diffusivity diamondoids heavy organic particles paraffin/wax particle deposition petroleum fluid prefouling behavior production operation,suspended particles turbulent flow

Interest of molecular functionalization for electrochemical storage

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Nano Research 2017年第12期10卷 4175-4200页

作者： Bihag Anothumakkool Dominique Guyomard joel Gaubicher Lenaic Madec Institut des Materiaux Jean Rouxel (IMN) Universite de Nantes CNRS 2 rue de la Houssiniere BP32229 44322 Nantes Cedex 3 France IPREM-ECP CNRS UMR 5254 Universite de Pau Helioparc Pau Pyrenees 2 av. PierreAngot 64053 Pau Cedex 9 France Reseau sur le Stockage Electrochimique de I'Energie (RS2E) CNRS FR3459 33 Rue Saint Leu 80039 Amiens Cedex France

Despite great interests in electrochemical energy storage systems for numerous applications, considerable challenges remain to be overcome. Among the various approaches to improving the stability, safety, performance, and cost of these systems, molecular functionalization has recently been proved an attractive method that allows the tuning of material surface reactivity while retaining the properties of the bulk material. For this purpose, the reduction of aryldiazonium salt, which is a versatile method, is considered suitable; it forms robust covalent bonds with the material surface, however, with the formation of multilayer structures and sp3 defects （for carbon substrate） that can be detrimental to the electronic conductivity. Alternatively, non-covalent molecular functionalization based on π-π interactions using aromatic ring units has been proposed. In this review, the various advances in molecular functionalization concerning the current limitations in lithium-ion batteries and electrochemical capacitors are discussed. According to the targeted applications and required properties, both covalent and non-covalent functionalizafion methods have proved to be very efficient and versatile. Fundamental aspects to achieve a better understanding of the funcfionalization reactions as well as molecular layer properties and their effects on the electrochemical performance are also discussed. Finally, perspectives are proposed for future implementation of molecular functionalization in the field of electrochemical storage.

关键词： electrochemical storage molecularfunctionalization covalent diazoniumchemistry non-covalent π-π interactions