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Recent development and challenges in enhancing fire performance on wood and wood-based composites:A 10-year review from 2012 to 2021

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Journal of Bioresources and Bioproducts 2024年第1期9卷 27-42页

作者： Charles michael Albert Kang Chiang Liew Faculty of Tropical Forestry Universiti Malaysia SabahKota Kinabalu 88400Kota KinabaluSabah 88400Malaysia

Due to their durability,versatility,and aesthetic value,wood and wood-based composites are widely used as building *** fact that these materials are flammable,however,raises a major worry since they might cause fire hazards and significant loss of life and *** article investigates the variables that affect fire performance as well as the various fire-retardant treatments and their *** current developments and challenges in improving the fire performance of wood and wood-based composites treated with fire-retardant materials are summarized in this ***,organic chemicals,and densification are some recent developments in fire-retardant treatments that are also *** points from the review are summarized,along with potential areas for further research and development.

关键词： Fire performance Fire-retardant materials Wood Wood-based composite Nanoparticles coating Surface charring Bio-based fire retardant Densification

Implementation and validation of a bonded particle model to predict rheological properties of viscoelastic materials

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Particuology 2024年第6期89卷 198-210页

作者： michael mascara Arno mayrhofer Stefan Radl Christoph Kloss Institute of Process and Particle Engineering Graz University of TechnologyInffeldgasse 13Graz8010Austria DCS Computing GmbH Industriezeile 35Linz4020Austria

This work focuses on implementing a particle-based method able to characterize viscoelastic materials whose rheological properties,such as storage modulus G′and loss modulus G″,are *** is based on the bonded particle model,with the elastic constitutive relation here substituted with a viscoelastic one to capture time-scale *** Burgers model,vastly used in literature to model viscoelastic systems,is discretized and *** test case used for calibration comprises of a cubic lattice,sheared with a periodic motion,to mimic the effect of a shear *** appropriate filtering of the stress response,the rheological properties are obtained,highlighting the effect of the lattice geometry,as well as the particle size,on the accuracy of the ***,the Burgers parameters are calibrated by analytically fitting the experimental dataset,showing the limitation of the Burgers *** micro-contact parameters are obtained from the macro parameters through appropriate *** completing a frequency sweep,the simulated G′and G″show a relatively large error,around 25%for G’for *** this reason,a more robust model,namely the generalized maxwell model,has been *** calibration procedure is performed in the same fashion as for the Burgers ***,the tangential micro-contact parameters are scaled *** normal *** scaling parameter,calledα,is calibrated by minimizing the root mean square error between simulation and experimental data,giving errors below 10%in both G′and G″for a large ***,a full ring plate-plate rheometer setup is simulated,and the simulation is compared with the given experimental dataset,again finding a good agreement.

关键词： DEm Rheology Numerical modeling Viscoelasticity

Increasing realism in modelling energy losses in railway vehicles and their impact to energy-efficient train control

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Railway Engineering Science 2024年第3期32卷 257-285页

作者： michael Nold Francesco Corman Institute for Transport Planning and Systems ETH ZürichZürichSwitzerland

The reduction of energy consumption is an increasingly important topic of the railway ***-efficient train control(EETC)is one solution,which refers to mathematically computing when to accelerate,which cruising speed to hold,how long one should coast over a suitable space,and when to *** approaches in literature and industry greatly simplify a lot of nonlinear effects,such that they ignore mostly the losses due to energy conversion in traction components and *** fill this research gap,a series of increasingly detailed nonlinear losses is described and *** categorize an increasing detail in this representation as four *** study the impact of those levels of detail on the energy optimal speed *** do this,a standard approach based on dynamic programming is used,given constraints on total travel *** evaluation of multiple test cases highlights the influence of the dynamic losses and the power consumption of auxiliary components on railway trajectories,also compared to multiple *** results show how the losses can make up 50%of the total energy consumption for an exemplary *** them would though result in consistent but limited errors in the optimal ***,more complex trajectories can result in less energy consumption when including the complexity of nonlinear losses than when a simpler model is *** effects are stronger when the trajectory includes many acceleration and braking phases.

关键词： Train trajectory optimization Energy-efficient train control(EETC) Dynamic efficiency Power losses in railway vehicles

microscale shaping and rounding of ridge arrays and star pattern features on nickel mould via electrochemical polishing

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Advances in manufacturing 2024年第2期12卷 207-226页

作者： Sana Zaki Nan Zhang michael D.Gilchrist School of mechanical and materials Engineering University College DublinBelfieldDublin 4Ireland

High quality micro mould tools are critical for ensuring defect-free production of micro injection moulded *** demoulding stage of the micro injection moulding can adversely affect the surface integrity due to friction,adhesion and thermal stresses between the metallic mould and polymeric replicated *** the present work,we propose the use of precision electropolishing(EP)as a shaping and polishing process to control the draft angle and fillet radius of micro features in order to ease *** defects that occur in replicated polymer parts include cracks,burrs and distorted features.A nickel mould having multiple linear ridges and star shape patterns was designed for the present investigation to have characteristic dimensions ranging from 10μm to 150μm and with various aspect ratios to study the effect of electropolishing on modifying the shape of micro features and surface morphology.A transient 2D computational analysis has been conducted to anticipate the effect of shaping on the Ni mould after electrochemical polishing with non-uniform material removal rates,based on the distribution of current *** experimental results indicate that after shaping using EP,the draft angle of star-patterns and linear patterns can be effectively increased by approximately 3.6°,while the fillet radius increases by up to 5.0μ*** controlling the electropolishing process,the surface roughness can be maintained under 50 *** work uses a green and environmental friendly nickel sulfamate electrolyte which can be effective for shaping of nickel micro features without causing any surface deposition.

关键词： micro feature shaping and electropolishing micro mould tools Green electrolyte Demoulding micro patterns

On Perron’s Formula and the Prime Numbers

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Advances in Pure mathematics 2024年第6期14卷 487-494页

作者： michael m. Anthony Department of Engineering Enertron Inc. Hohenwald Tennessee USA

The Riemann hypothesis is intimately connected to the counting functions for the primes. In particular, Perron’s explicit formula relates the prime counting function to fixed points of iterations of the explicit formula with particular relations involving the trivial and non-trivial roots of the Riemann Zeta function and the Primes. The aim of the paper is to demonstrate this relation at the fixed points of iterations of explicit formula, defined by functions of the form limT∈Ν→∞fT(zw)=zw,where, zwis a real number.

关键词： Perron Fixed Points Iterations Number Theory Riemann Hypothesis Iterations Invariance Primes

Phrenic nerve block: the key to managing acute biliary pain?

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World Journal of Emergency medicine 2024年第1期15卷 62-63页

作者： michael Shalaby Joshua Luftig Department of Emergency medicine and Critical Care Herbert Wertheim College of Medicine at Florida International UniversityMiami 33199USA Advanced Emergency Ultrasound Mount Sinai Medical CenterMiami Beach 33140USA Department of Emergency medicine Highland HospitalAlameda Health SystemOakland 94602USA

Over the past two decades,the USA has witnessed a steep rise in the incidence of acute cholecystitis(AC),[1]even among children,[2]with over 200,000 cases annually.[3]Patients with AC often present to the emergency department(ED)experiencing severe distress,with most describing their pain level as“intolerable.”[4]Furthermore,there is usually a considerable delay before surgery,with a median time from diagnosis of AC to surgery of 28.5 h,[5]and a substantial percentage of patients wait as long as 10 d.[6]Prolonged delays before surgery lead to increased opioid use,which is associated with extended hospital stays and higher rates of readmission after cholecystectomy.[7]Furthermore,opioids can lead to vomiting,respiratory depression,delirium,and ultimately addiction.[8]We propose a novel regional anesthesia technique for managing AC:right phrenic nerve *** method could offer improved pain control and a more favorable risk profile in selected patients when compared to current ED practices.

关键词： pain anesthesia diagnosis

Universal Hyperthermal model for mass Extinctions

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Journal of Earth Science 2024年第2期35卷 704-707页

作者： michael J.Benton Paleobiology Research Group School of Earth SciencesUniversity of BristolLife Sciences BuildingTyndall AvenueBristolBS81TQUK

INTRODUCTION Earth scientists have long sought universal features of past extinction *** can be argued that each past extinction event was a singularity,caused by combinations of circumstances that are unique in each case,and therefore that the search for common causes is ***,a key feature of the uniformitarian approach to geology is that past processes are the same as modern-day processes and,with that in mind,earth scientists are keen to use their knowledge to contribute some understanding to the study of the present and future climate crisis.

关键词： extinction singularity Extinction

Sleep quality and characteristics of older adults with acute cardiovascular disease

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Journal of Geriatric Cardiology 2024年第3期21卷 369-373页

作者： Haroon munir michael Goldfarb Faculty of medicine and Health Sciences McGill UniversityMontrealCanada Division of Cardiology Jewish General HospitalMcGill UniversityMontrealCanada

Sleep plays a vital role in restoring the physical and mental health of people with cardiovascular ***,the hospital setting is not a conducive environment for *** interruptions by members of the care team,including vital sign checks,medication delivery,and blood draws for laboratory investigations,are routinely done in many *** interruptions by staff and noise by other patients have been cited as barriers to restorative sleep in the hospital.

关键词： Sleep routine characteristics

Commentary on"Speed and surface steepness affect internal tibial loading during running"

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Journal of Sport and Health Science 2024年第1期13卷 125-126页

作者： michael Baggaley Arash Khassetarash Faculty of Kinesiology University of CalgaryCalgaryAB T2N 1N4Canada mcCaig Institute for Bone and Joint Health University of CalgaryCalgaryAB T2N 4Z6Canada

It is a pleasure to write a commentary on the work of *** Rice and colleagues,l who have advanced our understanding of how the mechanical loading environment of the tibia changes as a function of running grade and *** is important that we understand how the tibia is loaded during conditions that an individual is likely to encounter when running as it is these internal loads which we believe are responsible for the development of bone-stress injuries.

关键词： loading injuries likely