Erratum to“Probing the Interfacial Forces and Surface Interaction Mechanisms in Petroleum Production Processes”[Engineering 18(2022)49-61]

In Ref.[1],Eq.(8)has a typo,the following replacement should be done.γ_(bb)/2rδ/δr(rδ(r,t)/δr=2γ_(bb)/R_(bb)-Þ(t,t)-Ⅱ[h[r,t)](bubble=drop-bubble=drop)The publisher regrets an error in the original–article,and the sentence that explained the equation“Eqs.(8)–(10)show the augmented Young–Laplace equation for the interactions of gas bubbles or liquid droplets in different configurations,where Rb is the bubble/drop radius,Rp is the particle radius,Rbp=(1/Rb+1/Rp)1.

Probing the Interfacial Forces and Surface Interaction Mechanisms in Petroleum Production Processes

Despite the advances that have been made in renewable energy over the past decade,crude oil or petroleum remains one of the most important energy resources to the world.Petroleum production presents many challenging issues,such as the destabilization of complex oil-water emulsions,fouling phenomena on pipelines and other facilities,and water treatment.These problems are influenced by the molecular forces at the oil/water/solid/gas interfaces involved in relevant processes.Herein,we present an overview of recent advances on probing the interfacial forces in several petroleum production processes(e.g.,bitumen extraction,emulsion stabilization and destabilization,fouling and antifouling phenomena,and water treatment)by applying nanomechanical measurement technologies such as a surface forces apparatus(SFA)and an atomic force microscope(AFM).The interaction forces between bitumen and mineral solids or air bubbles in the surrounding fluid media determine the bitumen liberation and flotation efficiency in oil sands production.The stability of complex oil/water emulsions is governed by the forces between emulsion drops and particularly between interface-active species(e.g.,asphaltenes).Various oil components(e.g.,asphaltenes)and emulsion drops interact with different substrate surfaces(e.g.,pipelines or membranes),influencing fouling phenomena,oil-water separation,and wastewater treatment.Quantifying these intermolecular and interfacial forces has advanced the mechanistic understanding of these interfacial interactions,facilitating the development of advanced materials and technologies to solve relevant challenging issues and improve petroleum production processes.Remaining challenges and suggestions on future research directions in the field are also presented.

Vehicular Electronic Image Stabilization System Based on a Gasoline Model Car Platform

Noise,vibration and harshness(NVH)problems in vehicle engineering are always challenging in both traditional vehicles and intelligent vehicles.Although high accuracy manufacturing,modern structural roads and advanced suspension technology have already significantly reduced NVH problems and their impacts;off-road condition,obstacles and extreme operating condition could still trigger NVH problems unexpectedly.This paper proposes a vehicular electronic image stabilization(EIS)system to solve the vibration problem of the camera and ensure the environment perceptive function of vehicles.Firstly,feature point detection and matching based on an oriented FAST and rotated BRIEF(ORB)algorithm are implemented to match images in the process of EIS.Furthermore,a novel improved random sampling consensus algorithm(i-RANSAC)is proposed to eliminate mismatched feature points and increase the matching accuracy significantly.And an adaptive Kalman filter(AKF)is applied to improve the adaptability of the vehicular EIS.Finally,an experimental platform based on a gasoline model car was established to validate its performance.The experimental results show that the proposed EIS system can satisfy vehicular performance requirements even under off-road condition with obvious obstacles.

Probing the intriguing frictional behavior of hydrogels during alternative sliding velocity cycles

Understanding the friction behavior of hydrogels is critical for the long-term stability of hydrogelrelated bioengineering applications.Instead of maintaining a constant sliding velocity,the actual motion of bio-components(e.g.,articular cartilage and cornea)often changes abruptly.Therefore,it is important to study the frictional properties of hydrogels serving under various sliding velocities.In this work,an unexpected low friction regime(friction coefficientμ<10^(-4) at 1.05×10^(-3) rad/s)was observed when the polyacrylamide hydrogel was rotated against a glass substrate under alternative sliding velocity cycles.Interestingly,compared with the friction coefficients under constant sliding velocities,the measuredμdecreased significantly when the sliding velocity changed abruptly from high speeds(e.g.,105 rad/s)to low speeds(e.g.,1.05×10^(-3) rad/s).In addition,μexhibited a downswing trend at low speeds after experiencing more alternative sliding velocity cycles:the measuredμat 1.05 rad/s decreased from 2×10^(-2) to 3×10^(-3) after 10 friction cycles.It is found that the combined effect of hydration film and polymer network deformation determines the lubrication and drag reduction of hydrogels when the sliding velocity changes abruptly.The observed extremely low friction during alternative sliding velocity cycles can be applied to reduce friction at contacted interfaces.This work provides new insights into the fundamental understanding of the lubrication behaviors and mechanisms of hydrogels,with useful implications for the hydration lubrication related engineering applications such as artificial cartilage.