bluuebunny/crossref_metadata_2025 huggingface dataset:
From Single Particle Drag Force to Segregation in Fluidised Beds
Authors: Di Renzo A. , Di Maio F. P.
Published: January 2023

Discrete Element Modelling has been successfully applied in combination with fluid flow solvers (CFD) to tackle important multi-phase process engineering problems. However, until recently most of the DEM-CFD studies have dealt with monodisperse particulate systems. The reason for that is that DEM requires knowledge of the force exerted by the flowing fluid on each particle. While numerous expressions are available for homogenous systems, the presence of size polydispersion or the presence of solids mixtures complicate particle-level formulations of the drag force considerably and a general model is still lacking.

In the present contribution a drag force model for polydisperse system is introduced and discussed. The expression was originally proposed in the literature on the basis of lattice-Boltzmann simulation results for flow through random polydisperse systems. However, its theoretical foundations were not fully recognised. The proposed formula requires the introduction of an average diameter, whose definition will be proved to be rigorously derivable provided that appropriate consistency constraints are considered. No other fitting or adjustable parameters are involved. In the case of a binary mixture of differently sized particles the resulting drag force is shown to depend both on size ratio and local volume fraction of the solids. Such precious particle-level information is then shown to be extendable to the macroscopic scale with attractive potentialities. On this basis, solution to the (open) problem of the segregation direction in a gas-fluidized bed of binary solids endowed with contrasting density and size differences will be suggested.
Effect of Solid And Liquid Heat Conductivities on Two-Phase Heat and Fluid Flows
Authors: Tsutsumi T. , Takeuchi S. , Kajishima T.
Published: January 2023

Liquid-solid two-phase flow with heat transfer is simulated, and the effects of temperature gradient within a solid object and particle mobility on heat transfer are studied. The interaction between fluid and particles is considered with our original immersed solid approach on a rectangular grid system. A discrete element model with soft-sphere collision is applied for particle-particle interaction. Governing equation of temperature is time-updated with an implicit treatment for the diffusion term, which enables stable simulation with particles of very high/low ratios of heat conductivity (from 1/1000 to 1000) to fluid. The local heat flux at the fluid-solid interface is carefully discretised and incorporated into the implicit scheme of temperature. The method is applied to a 2-D confined flow including multiple particles under a high Rayleigh number condition. Heat transfer and particle behaviours are studied for different ratios of heat conductivity (solid to liquid) and solid volume fractions. For a relatively low solid volume fraction, a transition of particulate flow pattern is observed depending on the heat conductivity ratio; the cases with high ratios of heat conductivities exhibit simple (single or double) circulating flows, whereas low heat conductivity ratio causes complicated flow patterns involving multiple circulation of particles, resulting in low Nusselt number. The above simulation results, together with the heat transfer properties under a near-packed condition, highlight the effect of temperature distributions within the particles and liquid.
Gravitational Sedimentation and Separation of Particles in a Liquid: a 3D DEM/CFD Study
Authors: Qiu L. , Wu C.-Y.
Published: January 2023

This paper presents a numerical investigation of sedimentation and separation of particles in liquids using a modified discrete element method coupled with computational fluid dynamics (DEM/CFD). In the present DEM/CFD, a weakly compressible fluid model is incorporated to model continuum carrier (liquid) phases, while a soft-sphere based DEM is used to model discrete particles. The key advantage of DEM over continuum methods is that it can be used to analyze sedimentation behaviour at the particle level and to model explicitly particle–particle and particle–wall collisions. Using the modified DEM/CFD, computational simulations of settling of spherical particles in a container fully filled with water have been conducted to examine effects of particle size, particle density, particle concentration and fluid viscosity on gravitational sedimentation of particles. A three dimensional numerical simulation of stratification and particle segregation in a liquid is also performed. It has been demonstrated that the modified DEM/CFD is a robust numerical technique for analyzing complex sedimentation and separation process of particles in liquids in 3D.
The Effect of Initial Bed Height on the Behaviour of a Soil Bed Due to Pipe Leakage Using the Coupled DEM-LBM Technique
Authors: Cui X. , Li J. , Chan A. H. C. , Chapman D.
Published: January 2023

Leakage from underground pipes could result in foundations being undermined, surface subsidence, and damage to infrastructures. Soil particles surrounding the leaking area may be mobilised, raised, and even washed apart from the soil matrix by the leaking fluid, generating a subsurface cavity. Two-dimensional numerical simulations using a coupled Discrete Element Method (DEM) and Lattice Boltzmann Method (LBM) were used to investigate the bed behaviour due to a local leakage from a buried pipe. In this technique, the DEM was used for the modelling of the soil particles and the LBM for the modelling of the fluid. Immersed Moving Boundary (IMB) scheme was adopted for the treatment between the solid and fluid phases.

A parametric study was carried out with various values of initial bed height. Time evolutions of the pore pressures along the bed height and cavity development were explored. From the results, it is identified that the initial bed height influences neither the initial orifice pressure, nor the angle of the wedge at the onset of fluidisation which should be a property of the soil. However, it can be concluded that a soil bed with a deeper initial height leads to a slower decrease in the orifice pressure and a slower developing rate of the cavity. It is also worth noting that the cavity size at any particular moment relates linearly to the initial bed height, which may be of special importance in predicting cavity size at a particular moment with the initial bed height specified.
Modelling of the Contact Behaviour Between Fine Adhesive Particles with Viscous Damping
Authors: Mader K. , Tomas J.
Published: January 2023

On the basis of reference particle systems the single contact of two smooth spherical particles is shown. The comprehensive force displacement models of elastic-plastic, adhesive and frictional contacts are discussed. Titania and micro glass particles are selected on basis of their different physical properties. Therefore the model “stiff particles with soft contacts” is used to quantify and compare the elastic-plastic and frictional contact properties. The varying adhesion forces between the particles directly depend on this “frozen” irreversible deformation. So the adhesion force depends on the previous normal force as a history parameter.

The contribution of the load-dependent adhesion force to the tangential force in an elastic-plastic frictional contact, the rolling resistance and the torsional moment is also shown. In addition, the role of the contact consolidation coefficient is discussed. For relatively slow (quasistatic) motion and flow rates v < 1 m/s, the velocity-dependent damping force is assumed to be negligible. For processes with higher velocities, this assumption is not valid. Thus, the velocity-dependent viscous damping model by Tsuji et al. (Powder Technology, 1992,71,239-250.) was implemented into the contact model and simulated using Matlab.
Rebound of a Particle from a Solid Surface with a Viscous or Nonlinear Viscoelastic Liquid Film in the Contact Zone
Authors: Bowen J. , Cheneler D. , Andrews J.W. , Wu C-Y. , Ward M.C.L. , Adams M.J.
Published: January 2023

A summary is presented of previous work on the cohesive characteristics of thin films of viscous and nonlinear viscoelastic liquids that were studied using atomic force microscopy (AFM) for a range of separation velocities. It was possible to estimate the measured maximum cohesive forces as a function of the Capillary number by using models of the capillary and viscous forces, and also by developing a closed-form approximation for the nonlinear viscoelastic forces. Polymeric liquid binders are used in wet granulation and when the concentration and molecular weight exceed critical values, such binders are viscoelastic. In the current work, the models employed in the AFM studies were applied to the impact of particles on a planar half-space with viscous and viscoelastic liquid films in the contact region. This involved a simplistic description of an impact in which the elastic deformation of the particles was ignored. Nevertheless, it was demonstrated that, under conditions leading to stick for a viscous fluid, it is likely that a viscoelastic fluid will rebound. The molecular mechanisms involved are discussed in the paper.
Modelling of the Filtration Behaviour Using Coupled DEM and CFD
Authors: Stein S. , Tomas J.
Published: January 2023

The filtration by cake formation is an effective method to drain a particle suspension. One possibility to improve the filtration process is the formation of flocs, which deposit faster. The aim of this work is to predict the filtration behavior, the effects of flocculation and simulate the flow rate during generation and compression of the porous ultrafine particle packings by coupling Discrete Element Method and Computational Fluid Dynamics in two dimensions within the micron range. A Press-Shear-Cell was used to investigate the filtration behaviour of the consolidated particle packings and to measure the most important material properties.

It was shown that the time dependency of specific filtrate volume and cake height for the flocculated and non-flocculated suspension can be predicted by this method.

It is observed that a flocculation causes an increase in porosity and permeability of the filter cake. This results in decreasing filter cake resistances and increasing permeabilities. The filtration times are decreasing. A stable suspension with dominant repulsion produces a compact filter cake with small porosity, large filter cake resistance and poor permeability. The compressibility of the flocculated cake is higher compared to the stable suspension and can be categorized as very compressible.
DEM Modelling of the Digging Process of Gravel: Influence of Particle Roundness
Authors: Miyai S. , Katsuo T. , Tsuji T. , Takayama T. , Tanaka T.
Published: January 2023

To improve the energy efficiency of construction and mining machineries such as hydraulic excavator and bulldozer, it is important to optimize the shape of tools, which are used to handle ground materials directly such as buckets and blades, and earthmoving processes. It is impossible without a deep understanding of interactions between mechanical tools and ground materials. In the present study, a DEM model based on multi-sphere approach is developed for the gravel excavation process using a hydraulic excavator bucket. Granular materials in nature include several geometrical factors over different scales and it is computationally expensive to model real particle shapes as they are, especially for practical engineering design problems. It is mandatory to develop a simplified model which only includes essential geometrical factors that are important for gravel-tool interactions. In the present study, the role of particle roundness on digging process is investigated. We find that smaller roundness prevents the rotational motion of particles and strengthens the shear resistance of the layer. In addition, particles with higher angular velocity are localized in a narrow zone where the formation of shear band is expected during digging processes.
DEM Modelling of High Speed Die Filling Processes
Authors: Wu C.-Y. , Ogbuagu F. , Pei C.
Published: January 2023

Die filling is a process in which particles/granules are deposited into a cavity (i.e. a die) from a feed shoe/hopper and is a critical processing stage in the manufacture of particulate products, such as pharmaceutical and detergent tablets, catalyst pellets, ceramic and powder metallurgical components. In most particulate product manufacturing processes, a relative low filling speed (< 1 m/s) is normally employed. Nevertheless, high speed die filling processes have been developed recently for dosing individual granules, in which granules are deposited into a die when it travels at a speed up to 20 m/s passing under a stationary feed shoe/hopper. For this process, the mass flow rate is an important process parameter that controls the accuracy and consistency of granule dosing. In order to determine how the mass flow rate varies with the filling speed, in this study, the high speed die filling process was modelled using a discrete element method (DEM). In order to validate the DEM model, hopper flow with mono-disperse systems of various particle sizes was simulated and the mass flow rate was examined and compared with the prediction of Beverloo equation. Excellent agreements were obtained, demonstrating that the DEM can well predict the flow behaviour. DEM modelling of high speed die filling processes at various filling speeds were then performed. It was found that the mass flow rate in the high speed die filling process is proportional to the filling speed.
DEM Analysis of Loads on Disc Inserts Immersed in Grain During Silo Filling and Discharge
Authors: Kobylka R. , Molenda M.
Published: January 2023

The discrete element method (DEM) was used to estimate vertical loads on discs embedded in wheat during unloading of a model silo. DEM simulations were performed with an assembly of 40000 spherical particles, 3.8 mm in diameter, filling 0.1 m in diameter D cylindrical container. Material parameters of particles were chosen as measured for wheat kernels. Five disk inserts (with disc diameters to silo diameter d/D ratios as those used in laboratory experiments) were axially suspended at height h of h/D = 0.5 in the container and vertical loads on discs during filling and discharge were estimated. Insert loads during silo discharge were found in good agreement (up to certain disc diameter) with experimental results. The ratio of the mass of material in laboratory and numerical experiments was found a good scaling factor.
Modeling Packing of Spherical Fuel Elements in Pebble Bed Reactors Using DEM
Authors: Suikkanen H. , Ritvanen J. , Jalali P. , Kyrki-Rajamäki R.
Published: January 2023

Pebble bed reactor is a nuclear reactor type where the fuel material is in the form of coated particles dispersed inside graphite spheres of approximately 60 mm in diameter. Typical reactor contains about half a million of these pebbles that form a heat-producing column. Pebbles are fed on top and removed from the bottom of the column so that they flow through the core slowly. The column is cooled by helium gas flowing through the pebble bed.

Knowledge of the packing characteristics and behaviour of the fuel pebbles is important for resolving the core neutronics, burnup and thermal-hydraulics accurately. DEM can be used to model the mechanical interactions between pebbles accurately. The results can then be used in further analyses, e.g. as detailed pebble positions or packing density profiles.

In this work, an in-house DEM code was used to compact 450 000 pebbles inside an annular cylinder representing the core of a pebble bed reactor. Three pebble beds with different average packing densities were obtained by varying input parameters. Pebble-scale packing fraction data was extracted from the packed beds using Voronoi tessellation. The data was used to plot packing density profiles for different parts of the columns. The local packing fractions were also used for analyses with statistical and 3D visualization methods to reveal packing structure details. Local dense regions with crystallization were observed especially when the average packing density was high. The results are useful in further analyses, e.g. to identify hot spots in the reactor core.
DEM Triaxial Tests of a Seabed Sand
Authors: Macaro G. , Utili S.
Published: January 2023

DEM triaxial tests were run in a 3D periodic boundary cell containing 5000 spherical particles employing the open source code YADE to replicate the behavior of some typical seabed sands (i.e. Leighton Buzzard and North Australian shelf). The contact law adopted was the Hertz-Mindlin no-slip solution together with a linear moment – relative rotation law meant to account for the non-sphericity of the real sand grains. The chosen contact law is based on 5 independent micromechanical (i.e. at the level of contacts) parameters: two elastic parameters for the Hertz-Mindlin law, intergranular friction and two parameters for the moment - relative rotation law. The values for the elastic constants and the intergranular friction adopted in the simulations were taken from the elastic and frictional properties of the minerals of the sand grains (mainly quartz). Simulations were run for different values of the two parameters of the moment - relative rotation law. Tests were carried out on samples generated at various initial relative densities (from loose to very dense). The obtained results were very encouraging since the stress-strain behavior exhibited by the numerical samples well matched the experimentally measured values of critical state friction angle and dilatancy angle. However, dense samples showed a less good agreement regarding the peak friction angle.

The tests were carried out as part of a larger research program on the lateral soil-structure interaction for pipelines lying on sandy seabeds. An extensive program of 3D plain strain tests involving a plane strain section of the pipeline is currently underway.
The Steady State Solution of Granular Solid Hydrodynamics for Triaxial Compressions
Authors: Song S. , Sun Q. , Jin F.
Published: January 2023

By employing the complete continuum mechanical theory, also known as Granular Solid Hydrodynamics (GSH), the triaxial compression test was analyzed. The stress-strain and volumetric-deviatoric strain relation were calculated and were in reasonable agreement with experimental data. In addition, the steady state solution of GSH with the density ρ, the mean stress P and deviatoric stress q remain constant was discussed. There are three distinct behaviors in lnP-e phase: The very loose region is an unstable configuration; the normal density region is the most important for engineering and experiments, the void ratio and mean stress P have an approximately linear relationship; the over-density region has a solid-like mechanical behavior. Most of the experimental data in critical state are close to the results of GSH simulations. The calculated results demonstrate that the critical state in soil mechanics corresponds to the steady state solution of GSH.
Micromechanics of Seismic Wave Propagation in Granular Materials
Authors: O'Donovan J. , O'Sullivan C. , Marketos G.
Published: January 2023

This paper uses Discrete Element Method (DEM) simulations in order to obtain insight into the wave propagation mechanism through a granular material. A three dimensional face-centred cubic sample system was subjected to an isotropic confining stress. A seismic wave was generated by translating a single particle, in a situation analogous to a laboratory bender element test. The propagation of the wave-induced disturbance through the system was visualised by using particle scale methods such as plotting individual particle velocities and representative particle shear stresses. It was possible to compare the current study with previous research in the literature to identify different wave components. Arrival of the wave was found by tracking the displacement of a single particle in the sample (the receiver in a bender element test). Different travel time determination techniques available in the literature were used in an attempt to calculate an arrival time for the shear wave component and thus the velocity of the shear wave. The shear wave velocity was used to calculate a value for the shear modulus of the medium. A parametric study illustrating the effect of confining pressure on the sample shear modulus was carried out and agreement was found with theoretical predictions in the literature, even though the best way of identifying the wave travel time remains elusive.
Rare Earths
Authors: Hatch Gareth P.
Published: January 2023

Like a number of other rare metals, the rare earth elements (REEs) are enablers; their use is essential in many aspects of modern technology, with unique properties that can have a profound effect on the performance of complex engineering systems. As demand for REEs has increased in recent years, so have efforts to find new sources of supply outside China, which currently dominates the production of these materials. This chapter looks at the supply and demand dynamics of the rare earths sector, how these materials are used and processed and where they occur. It also looks at the recent challenges posed by export restrictions from China and the effects that these challenges have had on pricing. It also looks at the development of new exploration and development projects and efforts to recycle these materials.
Helium
Authors: Letcher Trevor M.
Published: January 2023

Helium is a very special element with a set of unique properties that dictate its many uses. Most of these uses relate to the cryogenic properties of helium. For many applications, there are no alternatives and it is indeed a strategic element. In this chapter, the uses of helium are discussed in terms of its properties. The amounts used for each application are discussed in terms of the total predicted reserves available, the origins of helium on Earth, the present extraction volumes and the possibility of exhausting the helium on Earth within the next 100–270 years.
Chemicals from Sugarcane
Authors: Galembeck Fernando , Macedo Gabriela Alves , Csordas Yara
Published: January 2023

Sugarcane has been a source of many chemicals in Brazil since the early 1940s. The increase in sugarcane production associated with the growing global demand for food (sucrose) and fuel (ethanol) has, since the early 1970s, led to a steady decrease in production costs and transformed sugarcane into an environmentally benign and economically competitive alternative to oil. Sugarcane is already a competitive feedstock for the production of a host of chemicals, including thermoplastics, solvents, surfactants, esters, ethers, carboxylic acids, amino acids, polyelectrolytes, gums and cellulose. Recent work, especially in Brazil, has produced a large number of new possibilities and many companies are implementing these. This chapter describes many examples of current products derived from sugarcane and also discusses possible future developments in this area.
Carbon Capture: Materials and Process Engineering
Authors: Florin Nick H. , Dowell Niall Mac , Fennell Paul S. , Maitland Geoffrey C.
Published: January 2023

Avoiding the catastrophic climate change consequences of greenhouse gas emissions, while continuing to use fossil fuels to meet the growing global energy demands of the twenty-first century, will require routine capture and storage of carbon dioxide (CO2). This chapter describes the materials and processes used for CO2 capture from power plants and industrial processes, both in the short term (amine-based solvents, calcium carbonate looping) and those likely to be exploited in the decades ahead (ionic liquids, metal oxides and chemical looping, solid sorbents, gas hydrates, metal–organic frameworks, gas membranes, biological systems such as algae and enzymes, cryogenic processes and building CO2 into materials such as urea and polycarbonate plastics). The potential for the integrated design and optimisation of materials and processes for capturing CO2 from a range of industrial sources is also described.
Carbon Dioxide as a Sustainable Industrial Solvent to Replace Organic Solvents
Authors: Howdle Steven M. , Pollak Stefan , Birkin Natasha A. , Warren Marie
Published: January 2023

The discussion about global warming and climate change has led to an increasing demand for reduced emission of the greenhouse gas carbon dioxide. An intelligent industrial use of CO2 in chemistry or process technology could also help to save the environment by replacing other ecologically harmful substances. One of the possible applications for CO2 is its use as a solvent. Although the dissolving power of gaseous CO2 is low to non-existent, it improves significantly in the liquid and supercritical states. For extraction applications, the use of CO2 as a solvent is already very well developed. Especially in the food sector it is utilised for the mild extraction of residue-free oils, aromas, flavours and essences. In other branches, the solvent CO2 is not as widespread, although, there are some interesting examples in technical cleaning, purification, impregnation, dyeing, reaction techniques and atomisation that are described in this chapter. These examples show that CO2 has the potential to become a benign ‘green’ solvent in many more applications.
Battery and Fuel Cell Materials
Authors: Salminen Justin , Kallio Tanja
Published: January 2023

Lithium ion battery-powered applications are rapidly increasing, especially for larger systems which include energy storage and some types of vehicles. Mass production capability exists for batteries but fuel cells are still made on a small scale. The global capacity for the industrial-scale production of large lithium ion battery cells or fuel cell systems is more likely to be the limiting factor than the shortage of natural resources if current plans for even partial electrification of vehicles or energy storage visions are to be realized. Strategic metals such as lithium, cobalt, platinum and rare earth metals are still readily available and current activities use relative small amounts. The recycling of valuable metals from both batteries and fuel cells is essential and opens up possibilities for the development of new technologies.
Materials for Photovoltaics
Authors: Forbes Ian , Peter Laurence M.
Published: January 2023

This chapter outlines the potential for photovoltaics (PV) to make a substantial contribution to the requirement for low carbon energy. Current and developing technologies are reviewed and assessed in terms of their energy payback times and carbon dioxide footprints. The constraints on the large scale deployment of existing non-silicon thin film PV technologies imposed by the availability and production levels of materials such as tellurium, indium and selenium are considered quantitatively using data from the UK and US geological surveys. The potential for thin film PV based on earth-abundant elements (e.g. Cu, Zn, Sn, S) is also examined. A simple logistic growth model is used to illustrate the likely impact in terms of resource demands of ramping up the installed PV capacity to reach 2 TW (peak) by 2050. The discussion highlights the need to consider possible bottlenecks now in order to develop the necessary capacity to meet the projections for PV made by a number of international organisations.
Glass and New Technologies
Authors: Kafizas Andreas , Parkin Ivan P.
Published: January 2023

This chapter focuses on the use of glass and new glass technologies for a sustainable future. It covers existing and future developments in window coatings for energy conservation and other purposes. Glass is the ultimate recyclable material as it can be melted and reused – in fact, using preformed glass acts as a catalyst for glass formation and reduces the energy requirements in glass manufacture. Coatings on windows can help reduce energy losses from houses in hot climates and reflect solar gain in hot climates. Glass coatings can also be used to self-clean the environment, reduce friction and to stop glass surfaces fogging. One exciting potential development is the use of these coatings to make photovoltaic devices.
Biomass in Composite Materials
Authors: Labet Marianne , Hossain Kazi M. Zakir , Ahmed Ifty , Thielemans Wim
Published: January 2023

Composite materials are materials constituted of two or more immiscible constituents to obtain properties which cannot be attained by the individual components. This chapter describes general trends in the use of biomass in composite materials used as the continuous polymer matrix, reinforcing fibres or fillers and as a compatibilising agent to strengthen the interaction between the individual phases.
Chemical Pollution of the Aquatic Environment by Priority Pollutants and its Control
Authors: Jones Oliver A. H. , Gomes Rachel L.
Published: January 2023

Modern society would not function without the chemical industry. Since the industrial revolution of the 18th and 19th centuries the number and diversity of man-made chemicals that find their way into aquatic environments has increased enormously. And there are now estimated to be well over 100 000 distinct chemical compounds marketed in the European Union alone but knowledge of the fate and effects of many of these is restricted to only a small proportion known to be particularly harmful and persistent. Against this background there has been concern that long-term exposure to chemicals and mixture for chemicals may be affecting both humans and the environment. Societal concerns over pollution have encouraged stricter and more innovative controls and regulations, but how effective are they, and will they be sufficient for emerging contaminates such as pharmaceuticals and nanoparticles? This chapter examines characteristic features of present pollution control regulations, with particular emphasis on recent European Union regulation of the aquatic environment, including the Water Framework Directive and the REACH regulations. Integrated Pollution Prevention and Control regulations are also introduced and potential risks and management options for the future are reviewed and discussed.
Treatment of Toxic Wastes
Authors: Wagland Stuart T. , Pollard Simon J. T.
Published: January 2023

Improving waste management to ensure resource recovery and responsible disposal requires us to consider all waste types. This extends beyond general household and commercial waste arising in daily life, which are typically deemed ‘non-hazardous’. This chapter discusses the definition of hazardous and toxic waste, including the properties which classify a solid or liquid waste as hazardous. Major sources of hazardous wastes are summarised here, and the prevailing options for management are explained. Hazardous waste, as with non-hazardous waste, needs to be handled in the most sustainable way that we can determine by avoiding direct disposal and maximising the recovery of resources, whilst ensuring that the potential impacts on environmental and human health are kept as low as reasonably practicable. The treatment options provided, including thermal and chemical processing, suit different types of waste (solid or liquid; combustible or non-combustible). Decisions based on an understanding of the waste are therefore important. Case studies are presented on specific wastes, treated wood and animal carcase, along with a case study which demonstrates the severe environmental consequences of poor hazardous waste management.
Atmospheric Dispersal of Pollutants and the Modelling of Air Pollution
Authors: Williams Martin L.
Published: January 2023

This chapter discusses the basic principles of atmospheric turbulence and stability, in a qualitative manner to ensure that the fundamental physical principles governing the dispersion of air pollutants are understood. There then follows a quantitative description of Gaussian plume modelling, with equations for point and line sources and a discussion of the properties of the plume standard deviations. The chapter goes on to discuss operational models which are now readily available for use by non-experts. A discussion of the compilation of emission inventories is given and their importance for modelling discussed. Recent developments in large sophisticated open source chemistry-transport models is also given and the chapter concludes with a discussion of the uncertainties in models
Impacts of Air Pollutants on Crops, Trees and Ecosystems
Authors: Ashmore Mike
Published: January 2023

This chapter provides an overview of the effects of major air pollutants on crop yields, forest health and ecosystem services, drawing primarily on examples from studies in Europe, but also in North America and Asia. It highlights key mechanisms underlying these effects of air pollution, and the interactions between effects of air pollutants and other environmental stresses. For all the air pollutants considered, we have a good understanding of the mechanisms and effects on individual plants, but the cascade of effects, and the interactions with other biotic and abiotic factors, which lead to effects at an ecosystem and landscape scale are much less certain. There is clear evidence that current levels of air pollution across Europe can reduce the food, fuel and fibre provided by ecosystems, modify the way that ecosystems contribute to regulation of water, climate and pollination, and degrade the cultural services they provide, although, in some cases, enhancement of these ecosystem services can also occur. The greatest effects of air pollution over this century, however, are likely to be in regions of the world where we know very little about the response to air pollution of the local crops and plant communities.
System Approaches: Life Cycle Assessment and Industrial Ecology
Authors: Clift Roland
Published: January 2023

Industrial Ecology (IE) is a general systems approach to economic activities which “seeks to optimise the total materials cycle from virgin material, to component, to product, to obsolete product and to ultimate disposal”. The industrial ecology approach looks beyond pollutant emissions to avoid forming the pollutants; clean technology, resource efficiency and pollution prevention are therefore part of the IE agenda, along with recovery, re-use and recycling of products and materials in a “circular”, “closed-loop” or “performance” economy. The analytical tools most widely used in IE are Life Cycle Assessment (LCA) and Material Flow Accounting (MFA). This chapter gives an introduction to LCA, MFA, and the way of thinking embodied in Industrial Ecology.
The Regulation of Industrial Pollution
Authors: Bigg Martin G.
Published: January 2023

Industrial Pollution Regulation has changed significantly over the past 150 years since the 1863 Alkali &c Works Regulations Act. Requirements have evolved from the use of the “best practicable means” and “best available technology not entailing excessive cost” to the use of the “best available technique”. Separate legislation for the control of releases to air and water, disposal to land and waste management replaced by integrated pollution prevention and control regulation, is now being delivered through standardised permitting, reporting and compliance assessment. More manufacturing and energy activities are covered by the legislation including farming and food production. Most UK legislation is now derived from or is a direct implementation of European legislation. Reference standards are developed at a pan European level to secure greater consistency, and revised as operational and control techniques develop and science improves. Regulators work more closely together but have also been restructured to reflect national needs. However, economic, business and political challenges have changed pollution regulation. The requirements to take account of economic aspects and a risk based approach are stronger. Regulators are more tightly beholden to the needs of government, business as well as communities. Environmental management systems are increasingly seen as environmental performance tools as well as the use of incentives, civil and criminal penalties. Pressure continues to simplify and reduce the burden of regulation on business.
First-principles screening of transition metal doped anatase TiO2(101) surfaces for the electrocatalytic nitrogen reduction
Authors: Ji Yongfei , Liu Paiyong , Huang Yungan
Published: January 2023

Au-doped anatase TiO2(101) surface was identified as a promising candidate for efficient electrocatalytic nitrogen reduction reaction.
Strong Ruδ+–Ce3+ electronic interaction induced by a CeOy overlayer for enhanced low-temperature N2-to-NH3 conversion
Authors: Li Lingling , Zhang Mingyuan , Zhang Tianhua , Gao Yinglong , Ni Jun , Zhou Yanliang , Lin Jianxin , Wang Xiuyun , Jiang Lilong
Published: January 2023

The low-temperature N2-to-NH3 conversion of Ru/BN catalysts could be improved via dopant of Ce species. A strong Ruδ+–Ce3+ electronic interaction induced by a CeOy overlayer resulted in an excellent performance for NH3 synthesis over RuCex/BN.
Pd nanoparticles-decorated borophene nanosheets for intrinsic polarization-induced visible light photocatalysis
Authors: Pratihar Bitan , Jana Animesh , Biswas Souvik , De Sirshendu
Published: January 2023

The electron transfer from Pd to boron in the Pd–B heterostructure creates an intrinsic polarization that facilitates effective separation of photogenerated charge carriers for photocatalytic degradation of organic pollutants.
Degradation of sulpiride in water by the UV/chlorine process: kinetics, reaction mechanism, and transformation pathways
Authors: Zhang Heng , Chen Miao , Guo Changsheng , Fan Jingpu , Xu Jian
Published: January 2023

The kinetics and reaction mechanism of sulpiride (SLP) degradation in the UV/chlorine system were investigated.
First-principles prediction of two-dimensional MnOX (X = Cl, Br) monolayers: the half-metallic multiferroics with magnetoelastic coupling
Authors: Feng Yulin , Wang Zilong , Liu Na , Yang Qing
Published: January 2023

Robust magnetoelastic coupling in the MnOBr monolayer.
Atomic structure and large magnetic anisotropy in air-sensitive layered ferromagnetic VI3
Authors: Wang Wenjie , Sun Rong , Shen Wei , Jia Zhiyan , Deepak Francis Leonard , Zhang Yujie , Wang Zhongchang
Published: January 2023

We report the air-sensitivity, atomic structure, and magnetic anisotropy of VI3 single crystals.
Enhanced in-plane thermal conductivity of polyimide-based compositesvia in situinterfacial modification of graphene
Authors: Lan Huiya , Wu Bin , Yan Yuye , Xia Ru , Qian Jiasheng
Published: January 2023

PI-based graphene heat conductive composite with low interfacial thermal resistance was prepared via in situ polymerization involving modified graphene. Thermal conductivity of an integrated composite with multi-aspect covalent bonding was enhanced.
The self-assembly of a pair of low-symmetry tetracarboxylic acid molecules and their co-assembly with bridging molecules at the liquid–solid interface
Authors: Zhang Siqi , Li Jianqiao , Gan Linlin , Ma Lin , Ma Wei , Zhang Min , Cheng Faliang , Deng Ke , Zeng Qingdao
Published: January 2023

In this work, the self-assembly behavior of a pair of low-symmetry carboxylic acid molecules (H4OBDB and H4ADDI) and their co-assembly behavior with trimesic acid (TMA) as a bridging molecule were studied using a scanning tunneling microscope (STM).
Design and enhanced anticorrosion performance of a Zn5Mo2O11·5H2O/h-BN nanocomposite with labyrinth of nanopores
Authors: Wang Feng-Rui , Sheng Xiao-Xiao , Zhang Min , Miao Min , Liu Jin-Ku , Liu Ji-Chang , Ma Yun-Sheng , Liu Peng-Peng
Published: January 2023

The figure exhibited the material structure and formulated the corrosion path and the corrosion prevention mechanism.
Initiating abilities of diphosphine- and diamine-ligated Pd complexes/NaBPh4 systems for C1 polymerization of diazoacetates
Authors: Shimomoto Hiroaki , Miyano Yuto , Kinoshita Kaito , Itoh Tomomichi , Ihara Eiji
Published: January 2023

(Diamine)Pd(0)(dichlone)/NaBPh4 systems have been revealed to be effective initiators for diazoacetate polymerization, yielding moderately syndiotactic polymers in moderate yields.
Preferential formation of specific hexose and heptose in the formose reaction under microwave irradiation
Authors: Hashidzume Akihito , Imai Toru , Deguchi Nanako , Tanibayashi Takashi , Ikeda Takumi , Michitaka Tomohiro , Kuwahara Satoki , Nakahata Masaki , Kamon Yuri , Todokoro Yasuto
Published: January 2023

The formose reaction proceeded very fast using Ca(OH)2 as a catalyst under microwave irradiation at a high temperature for a short time to form preferentially specific hexose and heptose.
Insights into structure–property relationships in ionic liquids using cyclic perfluoroalkylsulfonylimides
Authors: Bejaoui Younes K. J. , Philippi Frederik , Stammler Hans-Georg , Radacki Krzysztof , Zapf Ludwig , Schopper Nils , Goloviznina Kateryna , Maibom Kristina A. M. , Graf Roland , Sprenger Jan A. P. , Bertermann Rüdiger , Braunschweig Holger , Welton Tom , Ignat'ev Nikolai V. , Finze Maik
Published: January 2023

Ionic liquids with three cyclic perfluoroalkylsulfonylimide anions that are related to the bis(trifluoromethylsulfonyl)imide anion are described, which show the importance of conformational flexibility on IL properties.
Biomimetic gold nanomaterials for biosensing, bioimaging and biotherapy: a mini-review
Authors: Zhu Danzhu , Zhang Xiaoting , Han Yipeng , Luan Xin , Wei Gang
Published: January 2023

Biomimetically synthesized gold nanomaterials exhibit wide applications in the fields of biosensing, bioimaging, and biotherapy.
Comment on “Insight of the preponderant role of the lattice size in the Sn-based colusite for promoting high power factor” by P. Kamińska, C. Bourgès, R. Chetty, D. Gutiérrez-Del-Río, P. Śpiewak, W. Święszkowski, T. Nishimura, T. Mori, J. Mater. Chem. A, 2022, 10, 10701
Authors: Guilmeau E.
Published: January 2023

The aim of the present comment is to draw attention to the crystal chemistry of thermoelectric sulphides which requires detailed investigations to understand the close relationships between crystal structures, chemical compositions and transport properties.
Understanding the dopant of hole-transport polymers for efficient inverted perovskite solar cells with high electroluminescence
Authors: Zhou Qisen , Qiu Junming , Zhuang Rongshan , Mei Xinyi , Hua Yong , Zhang Xiaoliang
Published: January 2023

The fundamental interplay between F4TCNQ and PTAA is systematically studied, which reveals that the π–π stacking formed between F4TCNQ and PTAA is favorable for improving the spatial configuration of PTAA and thus the charge transfer.
Anion vacancy correlated photocatalytic CO2 to CO conversion over quantum-confined CdS nanorods under visible light
Authors: Guo Qing , Xia Shu-Guang , Xin Zhi-Kun , Wang Yang , Liang Fei , Nan Xiao-Lei , Lin Zhe-Shuai , Li Xu-Bing , Tung Chen-Ho , Wu Li-Zhu
Published: January 2023

In terms of electronic structure change, surface anion vacancies in II–VI semiconductors could promote CO generation rates, which have been confirmed as active sites for photocatalytic CO2 reduction.
Photocatalytic hydrogen production: an overview of new advances in structural tuning strategies
Authors: Xu Fenghua , Weng Baicheng
Published: January 2023

Newly emerged structural tuning strategies, i.e., singe atom photocatalysts, defect control and S-scheme heterojunctions, display significant advancements for high performance photocatalytic hydrogen production toward the industrialization target.
Formation of ZnS quantum dots using green tea extract: applications to protein binding, bio-sensing, anti-bacterial and cell cytotoxicity studies
Authors: Haque Mahabul , Konthoujam Ibemhanbi , Lyndem Sona , Koley Sudipta , Aguan Kripamoy , Singha Roy Atanu
Published: January 2023

Applications of biocompatible ZnS-GT QDs (synthesized using green tea extract) are reported for cytotoxicity against HeLa cancer cells, anti-bacterial activity, binding interactions with the HSA protein, and rifampicin and bilirubin biosensing.
Binder polymer influence on the electrical and UV response of organic field-effect transistors
Authors: Li Jinghai , Tamayo Adrián , Quintana Aleix , Riera-Galindo Sergi , Pfattner Raphael , Gong Yanyan , Mas-Torrent Marta
Published: January 2023

Organic field-effect transistors (OFETs) and phototransistors using blends of Ph-BTBT-10 with binding polymers are prepared. We show that tuning the nature of the polymer is a useful tool to optimise the OFET performance and photoresponsivity.
Fused perylene diimide-based polymeric acceptors for all-polymer solar cells with high open-circuit voltage
Authors: Wang Lei , Hu Ming , Liu Xia , Zhang Youdi , Liu Yue , Yuan Zhongyi , Zhao Xiaohong , Hu Yu , Chen Yiwang
Published: January 2023

A high VOC (0.936 V) was obtained in P(TBDPDI-TT)-based all-PSCs. This study demonstrates that the fusing of PDI units to form a large coplanar aromatic system is an effective strategy for improving the VOC of all-PSCs based on PDI acceptor polymers.
Curriculum-Based Dynamic Assessment of Narratives for Bilingual Filipino Children
Authors: Laurie Anne , Pesco Diane
Published: January 2023

Purpose:

Speech-language pathologists need tools that can accurately estimate bilingual children's language abilities and thus help avoid misdiagnoses. This study addresses this need by investigating the accuracy of a novel curriculum-based dynamic assessment of narratives in distinguishing bilingual children with language difficulties (LDs) from children with typically developing (TD) language.

Method:

Participants comprised 34 Filipino–English bilingual children attending elementary school in English: seven with LDs and 27 with TD language. All children were assessed on narrative skills relevant to their school curriculum during a dynamic assessment involving a test–teach–test sequence. We then examined how accurately the children's scores on narrative tasks completed during the test phases, and on a modifiability rating scale completed during the teaching phase, discriminated the LD and TD groups.

Results:

According to discriminant analyses, logistic regressions, and receiver operating characteristic curve analyses, the modifiability rating classified the children with 97.1% accuracy. Children's scores on the narrative measures following the teaching phase were also better at predicting language group than their initial scores, with the Test of Narrative Language–Second Edition (TNL-2) Narrative Language Ability Index score reaching 100% accuracy at posttest.

Conclusions:

The curriculum-based dynamic assessment of narratives shows promise at distinguishing TD language from LD in a group of understudied bilingual children that is rapidly growing in both Canada and the United States. The findings compare favorably to past studies of dynamic assessment and extend this work by integrating curricular goals to the narrative assessment process.