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Environmental Concern of Using Coal Tar in Road Engineering and Its Possible Alternatives

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武汉理工大学学报 2010年第17期32卷 1-7,17页

作者： XIAO y van de ven m F C mOLENAAR A A A wU s P Faculty of Civil Engineering & Geosciences Delft University of TechnologyP.O.Box 50482600 GA Delftthe Netherlands Key Laboratory of silicate materials science and Engineering of the ministry of Education Wuhan University of TechnologyWuhan 430070China

Coal tar,a by-product from the destructive distillation of coal in coking oven,is widely used in road engineering for its excellent adhesion and fuel resistance properties,especially for pavement surface treatments in gas stations and airports. However,coal tar has a high Polycyclic Aromatic Hydrocarbons (or PAHs) content,which makes it toxic. In 1985,the International Agency for Research on Cancer (IARC) has proved that coal tar is carcinogenic to humans. Research showed that Coal Tar-based sealers (CTs) contribute to the majority of PAHs pollution in the water *** of this environmental concern,CTs are not allowed in many developed countries in the UsA and Europe. In contrast,coal tar is still used for road engineering in China and is even used *** paper gives a literature review on the general information and research about environmental concern of using coal tar in road engineering. Based on the review,some possible alternatives to replace coal tar are described. These alternatives include nano-clay/epoxy modified bitumen/bitumen emulsion and waterborne polyurethane/epoxy resin,which are environmental friendly. They have the potential to perform as well as CTs,and even better in some special applications.

关键词： coal tar pavement surface treatment adhesion property polycyclic aromatic hydrocarbons modified bitumen emulsion

A Nanoindentation study on the Rheological Behaviour of Bituminous Binders

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武汉理工大学学报 2010年第17期32卷 47-50页

作者： LIU G van de ven m wU s P yU J y mOLENAAR A Faculty of Civil Engineering and Geosciences Delft University of TechnologyP.O. Box 50482600 GA Delftthe Netherlands Key Laboratory of silicate materials science and Engineering of ministry of Education Wuhan University of TechnologyWuhan 430070China

This paper reports the nanoindentation results of three bituminous binders,C-Fix,and standard penetration grade 40/60 bitumen and organo-montmorillonite (Omt) modified bitumen. Under a load applied by the Berkovich diamond indenter,a loading and unloading history was recorded and the load-displacement curve was analyzed as a function of time. The software can directly give an output value of the modulus for C-Fix. However the result was dependent on the loading history. Due to increasing viscoelastic behaviour,the output value of the modulus for base bitumen was always negative,even with a very short unloading time. In conclusion,the modulus calculated by the software was not suitable for the bituminous binders due to their time-dependence. The nanoindentation curve during the loading phase of bitumen could be described by the adopted creep model. The results indicated that the Omt modified bitumen showed a high creep resistance than the base bitumen due to the Omt's reinforcement.

关键词： nanoindentation bitumen viscoelasticity creep

Durable Asphalt Pavements Are self Healing

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武汉理工大学学报 2010年第17期32卷 30-34页

作者： QIU J van de ven m F C wU s P yU J y mOLENAAR A A A delft University of Technology P.O. Box 50482600 GA Delftthe Netherlands Key Laboratory of silicate materials science and Engineering Wuhan University of TechnologyWuhan 430070China

The traffic volume and the number of heavy vehicles are growing continuously. Considering the continuous traffic flow and the limited time available for road maintenance,it is very important to design a durable pavement system. Asphalt pavements with a healing capability are believed to be very useful since they can extend the pavement service life thanks to rest periods and hot summers. In order to design durable asphalt pavements,research in understanding and upgrading the self-healing capability of bituminous materials in time is of major importance. The self healing capability of bituminous mastic was evaluated in this research with a direct tension healing test. In the test program,different healing times,crack status and modifications were applied. The results indicate that elastic recovery and flow capacity are important factors for the self healing capability of bituminous materials at different crack phases as simulated with the direct tension test.

关键词： durability self healing cracking bituminous mastic elastic recovery flow

A Review on surface?Functionalized Cellulosic Nanostructures as Biocompatible Antibacterial materials

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Nano-micro Letters 2020年第6期12卷 90-112页

作者： mandana Tavakolian seid mahdi Jafari Theo Gmvan de ven department of Chemical Engineering McGill UniversityMontrealQC H3A 0C5Canada Pulp and Paper Research Center McGill UniversityMontrealQC H3A 0C7Canada Quebec Centre for Advanced materials(QCAm/CQmF) MontrealCanada department of Food materials and Process design Engineering Gorgan University of Agricultural Science and Natural ResourcesGorganIran department of Chemistry McGill UniversityMontrealQC H3A 0B8Canada

As the most abundant biopolymer on the earth,cellulose has recently gained significant attention in the development of antibacterial ***,renewability,strong mechanical properties,tunable aspect ratio,and low density offer tremendous possibilities for the use of cellulose in various *** to the high number of reactive groups(i.e.,hydroxyl groups)on the cellulose surface,it can be readily functionalized with various functional groups,such as aldehydes,carboxylic acids,and amines,leading to diverse *** addition,the ease of surface modification of cellulose expands the range of compounds which can be grafted onto its structure,such as proteins,polymers,metal nanoparticles,and *** are many studies in which cellulose nano-/microfibrils and nanocrystals are used as a support for antibacterial ***,little is known about the relationship between cellulose chemical surface modification and its antibacterial activity or *** this study,we have summarized various techniques for surface modifications of cellulose nanostructures and its derivatives along with their antibacterial and biocompatibility behavior to develop non-leaching and durable antibacterial *** the high effectiveness of surface-modified cellulosic antibacterial materials,more studies on their mechanism of action,the relationship between their properties and their effectivity,and more in vivo studies are required.

关键词： Cellulose Nanocellulose surface modification Antibacterial activity Biocompatibility

Low dose oral haloperidol does not prolong QTc interval in older acutely hospitalised adults： a subanalysis of a randomised double-blind placebo-controlled study

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Journal of Geriatric Cardiology 2018年第6期15卷 401-407页

作者： Edmee Jm schrijver maaike Verstraaten Peter m van de ven Pierre m Bet Astrid m van strien Carel de Cock Prabath wB Nanayakkara on behalf of all HARPOON Investigators department of Internal medicine VU University Medical Centre Amsterdam the Netherlands department of Cardiology VU University Medical Centre Amsterdam the Netherlands department of Epidemiology and Biostatistics VU University Medical Centre the Netherlands department of Clinical Pharmacology and Pharmacy VU University Medical Centre the Netherlands department of Geriatric medicine Jeroen Bosch Hospital s-Hertogenbosch the Netherlands

Background Haloperidol is the most frequently prescribed antipsycbotic for delirium symptoms. The risk of QTc prolongation often raises concerns, although the effect of haloperidol on QTc interval has not yet been investigated in a randomised placebo-controlled fixed-dose study. methods A subanalysis of a randomised double-blind placebo-controlled study was conducted to evaluate the effect of prophylactic haloperidol 1 mg or placebo 1 mg orally twice-daily （maximum of 14 doses） on QTc interval in patients aged 70 years and over. Bedside, 12-lead ECGs were recorded before, during and after the one-week intervention period. Automatic QTc measurements were ob- tained in addition to manual measurements of QT and RR intervals, blinded for treatment status. manual measurements were corrected （QTc） using Bazett （QTc-B）, Framingham （QTc-Fa）, Fridericia （QTc-Fi） and Hodges （QTc-H） methods. mixed model analyses were used to test for differences in longitudinal course of QTc between patients receiving haloperidol and placebo. Results ECG recordings of 72 patients （haloperidol n = 38） were analysed, 45.8% male. median （range） haloperidol serum concentration on day 4 was 0.71 （0.32-1.82） μg/L （n = 23）. Longitudinal course of mean QTc did not significantly differ between treatment arms for any of the automatic or manually derived QTc values. Conclusions Low dose oral haloperidol did not result in QTc prolongation in older acutely hospitalised patients. Results may not be generalizable to patients with existing ECG abnormalities such as atrial fibrillation.

关键词： Haloperidol Prolongation QTc interval The aged

Exploring water and ion transport process at silicone/copper interfaces using in-situ electrochemical and Kelvin probe approaches

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Journal of materials science & Technology 2021年第5期64卷 203-213页

作者： B.munirathinam J.P.B.van Dam A.Herrmann w.D.van Driel F.de Buyl s.J.F.Erich L.G.J.van der ven O.C.G.Adan J.m.C.mol delft University of Technology Department of Materials Science and Engineering DepartmentDelftThe Netherlands Eindhoven University of Technology Department of Applied PhysicsEindhovenThe Netherlands signify High Tech CampusEindhovenThe Netherlands delft University of Technology Electronic ComponentsTechnology and MaterialsFaculty of Electrical EngineeringDelftThe Netherlands Dow silicones Belgium s.p.r.l. Belgium

In general,packaging materials which encapsulate light emitting diodes(LEDs)and microelectronic devices offer barrier protection against several environmental hazards such as water and ionic ***,these encapsulants may provide pathways for water and ionic contaminants to reach the metal/polymer interfaces and provoke local corrosion of electronics,which is a major reliability concern for polymer encapsulated LEDs and *** the water and corrosive constituents play a crucial role in their reliability,water uptake kinetics,interfacial ion transport and delamination behaviour of silicone coated copper model system,mimicking a typical microelectronics packaging system,is explored in the present *** impedance spectroscopy(EIs)integrated with attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy studies revealed that water diffusion inside the silicone network is Fickian in nature and the evolution of the observed time constants are related to the diffusion and interfacial reactions.A decrease of impedance magnitude with time was observed in EIs measurements concurrently with water absorption bands shifting towards lower wavenumber in ATR-FTIR measurements,implying the growth of strong hydrogen bonding between water molecules and the silicone *** estimated diffusion constant of water using the capacitance method was in the order of 7×10^(-12)m^(2)s^(-1)and the water absorption volume fraction was in the range of 0%to 0.30%.scanning Kelvin probe studies elucidated the ion transport process occurring at the silicone/copper interface in a humid *** interfacial ion transport process is controlled by the interfacial electrochemical reactions at the cathodic delamination front and the estimated average delamination rate is 0.43 mm h^(-1/2).This work demonstrates that exploring ion and water transport in the silicone coating and along the silicone/copper interface is of pivotal importance as

关键词： silicone Impedance water transport scanning Kelvin probe delamination

machine-learning the configurational energy of multicomponent crystalline solids

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npj Computational materials 2018年第1期4卷 191-197页

作者： Anirudh Raju Natarajan Anton van der ven materials department University of CaliforniaSanta Barbara 93106 CAUSA

machine learning tools such as neural networks and Gaussian process regression are increasingly being implemented in the development of atomistic ***,we develop a formalism to leverage such non-linear interpolation tools in describing properties dependent on occupation degrees of freedom in multicomponent ***-adapted cluster functions are used to differentiate distinct local *** local features are used as input to neural networks that reproduce local properties such as the site *** apply the technique to reproduce a synthetic cluster expansion Hamiltonian with multi-body interactions,as well as the formation energies calculated from first-principles for the intercalation of lithium into *** formalism and results presented here show that complex multi-body interactions may be approximated by non-linear models involving smaller clusters.

关键词： solids cluster multicomponent

Vibration suppression in multi-tool ultrasonic machining to multi-external and parametric excitations

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维普期刊数据库

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Acta mechanica sinica 2009年第3期25卷 403-415页

作者： m.m.Kamel w.A.A.El-Ganaini y.s.Hamed department of Engineering mathematics Faculty of Electronic EngineeringMenoufiya University

Ultrasonic machining （Usm） is of particular interest for the machining of non-conductive, brittle materials such as engineering ceramics. In this paper, a multi-tool technique is used in Usm to reduce the vibration in the tool holder and have reasonable amplitude for the tools. This can be done via dynamic absorbers. The coupling of four nonlinear oscillators of the tool holder and tools representing ultrasonic cutting process are investigated. This leads to a four-degree-of-freedom system subjected to multi-external and multi-parametric excitation forces. The aim of this work is to control the tool holder behavior at simultaneous primary, sub-harmonic and internal resonance condition. multiple scale perturbation method is used to obtain the solution up to the second order approximations. The different resonance cases are reported and studied numerically. The stability of the system is investigated by using both phase-plane and frequency response techniques. The effects of the different parameters of the tools on the system behavior are studied numerically. Comparison with the available published work is reported.

关键词： Control stability Ultrasonic machining (Usm)

Effect of coating material and lubricant on forming force and surface defects in wire drawing process

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Transactions of Nonferrous metals society of China 2011年第A1期21卷 104-110页

作者： s.m.ByON s.J.LEE D.w.LEE y.H.LEE y.LEE department of mechanical Engineering Dong-A University department of mechanical Engineering Chung-Ang University wire Rod Research Group POSCO Technical Research Laboratories

A pilot wire drawing machine as well as wire end-pointing roller was developed. Using these machines, a wire drawing test for four different coating materials and two different lubricants was performed as the reduction ratio increased from 10% to 30%. materials used for a substrate in this study are plain carbon steel （AIs11045） and ultra low carbon bainite steel. To compute the friction coefficient between the coating layer of wire and the surface of die lbr a specific lubricant, a series of finite element analyses were carried out. sEm observations were also conducted to investigate the surface defects of wire deformed. Results show that the behavior of drawing force varies with the lubricant-type at the initial stage of drawing. The powder-typed lubricant with a large particle causes the retardation of lull lubrication on the entire contact surface and the local delamination of coating layer on the wire surface. As the flow stress of a substrate increases, the delamination becomes severe.

关键词： coating lubricant wire drawing delamination