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Studies on the efficacies of vermicomposting and composting in countering the toxic impacts of pollutant cocktails in municipal solid waste (MSW) are scarce. Moreover, further research is needed to explore earthworms' remediation preferences for various pollutants in heterogeneous vermicomposting feedstocks, such as MSW. Therefore, removal dynamics of pesticides (chlorpyrifos, cypermethrin, and carbofuran), pharmaceuticals (diclofenac and carbamazepine), and heavy metals (Pb, Zn, Cu, and Mn) in MSW-based vermicomposting (Eisenia fetida and Eudrilus eugeniae) and composting systems were evaluated through multivariate analytical techniques (principal component (PCA) and multi-factor (MFA)) on the R-platform. Both earthworms satisfactorily increased their population and augmented NPK (nitrogen, phosphorous, and potassium) availability, cation exchange, microbial biomass C&N, and their metabolic activity 2–3 folds more than composting, accompanied by a 3–4 folds reduction of organic C, pH, and bulk density. Correspondingly, heavy metals, pesticides, and pharmaceuticals decreased by 8-10-folds via earthworm's significant pollutant removal efficiencies that subsided MSW-driven ecological risks by 60–90%. PCA and MFA revealed that N, P, and K-availability, organic C, and microbial activity were the indicative attributes for heavy metal and emerging organic micropollutant (EOMP)-removal during biocomposting; however, earthworms remove pesticides faster than pharmaceuticals and heavy metals. PCA-based novel empirical models demonstrated that in MSW-only feedstock, earthworm-mediated pollutant detoxification followed the order of pesticides > pharmaceuticals > heavy metals. However, in MSW combined with cow dung (1:1 ratio) feedstock, the detoxification order shifted to pharmaceuticals > heavy metals > pesticides. Therefore, this study provides fresh insights into pollutant-focused feedstock optimization for vermicomposting through model-based approaches, advancing the eco-friendly valorization of toxic MSW. [Display omitted] • Vermitechnology has stronger positive influence on valorized MSW than composting. • Earthworms removed metals, pesticides, and pharmaceuticals from MSW by > 70%. • PCA and MFA showed that TOC, P, K & Ca reduction indicates high pollutant removal. • Novel empirical models could gauge earthworms' toxicant remediation preferences. [ABSTRACT FROM AUTHOR]

The dissolved inorganic carbon (DIC) produced by carbonate weathering may be lost by degassing or be biologically fixed as it transports from inland water to the ocean. Knowledge of DIC stability under these two processes in surface water systems is crucial for evaluating the role of carbonate weathering in the global carbon cycle. Here, we evaluated the net ecosystem productivity of aquatic ecosystems (NEPs), water‒air CO 2 exchange fluxes (FCO 2), and Carbon budgets (Carbon budget = ( T O C o u t p u t + 0.5 D I C o u t p u t ) − ( T O C i n p u t + 0.5 D I C i n p u t )) in five simulated spring-pond systems controlled by carbonate weathering and different land uses. Using these parameters and the unique structure of our simulation site, the stability of the carbonate weathering-driven carbon sink (DIC) in surface water was discussed. The results showed that the NEP and FCO 2 of the study site presented significant negative relationships and were mainly controlled by aquatic ecosystem metabolisms than abiotic processes. Most aquatic ecosystems in our study site were autotrophic (NEP>0) due to the strong biological carbon pump effect (BCP) induced by carbonate weathering. Moreover, the DIC input enhanced the FCO 2 in the warm season. The intensive BCP enhanced both CO 2 release and atmospheric CO 2 invasion. Moreover, we found that the stability of DIC was positively related to DIC input, which can be influenced by BCP and human land use. After considering the net changes in Carbon budget through the groundwater-surface water systems, a high average carbon stabilization rate (CSR) of approximately 103.7% of carbonate weathering carbon sink was found in our study site. This indicated that BCP could retain most of the DIC that was driven by carbonate weathering. Therefore, due to the high stability of the carbonate weathering carbon sink under the BCP, we stress that it should be considered a significant carbon sink in the global carbon cycle. [Display omitted] • The degassing of DIC in karst water is dominated by the aquatic metabolism. • Atmospheric CO 2 can directly invade karst water with strong aquatic photosynthesis. • Adjustment of land use will increase the stability of DIC. • The carbonate weathering carbon sink is a vital part of the global carbon cycle. [ABSTRACT FROM AUTHOR]

• Three innovative simplified methods of slatted floor in pig houses were developed. • Four CFD modeling approaches of slatted floor were used and compared. • The velocity and pressure under different modeling approaches were compared. • The theoretical basis for CFD simulation of different cases was provided. The slatted floor system is often used in pig housing. Computational Fluid Dynamics (CFD) is a valuable technique for determining the airflow and gas dispersion within the pit headspace through the slatted floor. However, there is a practical issue related to modeling the thousands of small slot openings in real livestock buildings for CFD simulation. It is unpractical to simulate the slatted floor with geometry details due to the large mesh number and the limited computer capacity. In this study, several methods to simplify the model of the slatted floor were explored to reduce the computational cost. The study was based on CFD analysis supported by experimental validation. The slatted floor was modeled in four ways: direct geometry method (DGM), porous-region method (POM), and profiled-porous-region method (including PPOM-cell (PPOM-C) and PPOM-floor (PPOM-F)). To assess the feasibility of the simplification, the four modeling approaches were compared with the experimental data. The results showed that it's feasible to model the slatted floor as POM or PPOM. The accuracy of POM was high, but it was greatly affected by the calculation of the resistance coefficient. PPOM-C has greatly reduced the amount of calculation, which could be used to simplify the large-scale pig house model whose flow fields and gas emissions below the slatted floor could be ignored. The simulation result of PPOM-F was the closest to DGM, however, due to the large number of meshes and complex setup, it was not suitable for practical simulation. [ABSTRACT FROM AUTHOR]

• A critical review on asphaltene precipitation/deposition is provided. • Mechanisms, main characteristics, theoretical models, and pros and cons of asphaltene precipitation are discussed. • Parametric sensitivity analysis highlights vital factors/impacts in asphaltene precipitation. • Focal challenges for research/engineering activities in asphaltene precipitation are listed. • Useful guidelines to manage asphaltene deposition in petroleum industry are recommended. Asphaltene is the heaviest and most polar fraction of crude oils, which is usually defined as a solubility class, soluble in light aromatics, benzene and toluene, and insoluble in paraffins. Asphaltene precipitation/deposition negatively affects a variety of oil and gas processes, including oil recovery, transportation, and petroleum processing as it exhibits some undesirable impacts such as an increase in the viscosity of crudes and stability of the emulsions, a decrease in the distillate yields, and unstable phase separation. Experimental and theoretical investigations have revealed that asphaltene precipitation/deposition is influenced by several parameters/variables, including pressure, temperature, characteristics of the involved mixtures, properties and amount of precipitants, and characteristics of porous media. Knowing the undeniable consequences of asphaltene precipitation/deposition such as reduction of well productivity and/or blockage of the surface facilities, the effective treatments or inhibition techniques have gained widespread attention in the petroleum industry so far. Hence, a comprehensive knowledge of previous findings and an adequate understanding of different aspects of asphaltene precipitation/deposition (e.g., mechanisms and characterization) seem to be pivotal. Various attempts have been made to investigate different aspects of this phenomenon including thermodynamics of precipitation, kinetics of flocculation, and deposition mechanisms. The previous studies and importance of asphaltene in the oil and gas industry inspired us to provide a comprehensive review of the asphaltene precipitation/deposition that helps to further understand the governing mechanisms, thermodynamic behaviors, and transport phenomena prospects in this area. In this review work, the theories and mechanisms of precipitation/deposition, experimental and modelling approaches, the effects of operational parameters, and treatment/inhibition techniques are reviewed. Moreover, the economic analysis of flow assurance and the most common theoretical and practical challenges in asphaltene precipitation/deposition are studied. [ABSTRACT FROM AUTHOR]

Abstract The applications of ejectors are many and encompass the refrigeration, the power generation and the chemical sectors. On one hand, ejector technology needs limited maintenance, has low operational costs and has no restrictions concerning the working fluids; on the other hand, the complex single- and multi-phase fluid dynamics make ejector design and performance prediction a real challenge. This perspective explores the main advancements in ejector technology and proposes a critical discussion with an outlook for the future research; the proposed discussion is grounded on the multi-scale relationship between the " local-scale " phenomena and the " component-scale " performances. After a look at the past, this perspective examines the ongoing research activities and achievements regarding four state-of-the-art research areas, namely refrigeration systems, power conversion plants, chemical process and technology and computational methods. For the different research areas discussed, directions and opportunities for the future research activities are appraised. Finally, this perspective defines a fundamental challenge that needs be addressed in the forthcoming long-term activities: " the multi-scale ejector challenge ". Highlights • " the multi-scale ejector challenge " should guide the future research. • Medium-term and long-term research activities are discussed. • Ongoing research activities and achievements are discussed. • Ejector technology and applications are discussed. • Ejector modeling approaches are presented and discussed. [ABSTRACT FROM AUTHOR]

Abstract The ideal picture of a near-perfect 3D microscope often presented regarding Atom Probe Tomography faces several issues. These issues degrade the metrological performance of the instrument and find their roots in the phenomena acting at the atomic to the mesoscopic level in the vicinity of the surface of a field emitter. From the field evaporation process at the atomic scale, to the macroscopic scale of the instrument, the path to model the imaging process and to develop more accurate and reliable reconstruction algorithms is not a single lane road. This paper focused on the numerical methods used to understand, treat, and potentially heal imaging issues commonly affecting the data in atom probe experiments. A lot of room for improvement exists in solving accuracy problems observed in complex materials by means of purely electrostatic models describing the image formation in a classical approach. Looking at the sample at the atomic scale, the phenomena perturbing the imaging process are subtle. An examination of atomic scale modifications of the sample surface in the presence of a high surface electric field is therefore mandatory. Atomic scale molecular dynamic models integrating the influence of the high surface electric are being developed with this aim. It is also demonstrated that the complex behavior of atoms and molecules in high fields, and consequences on collected data, can be understood through the use of accurate ab-initio models modified to include the impact of the extreme surface electric field. [ABSTRACT FROM AUTHOR]

This paper provides a comprehensive review of literature on integrated infrastructure systems with an emphasis on interdependency types and definitions, complex network abstractions, and on different modeling and simulation techniques. An infrastructure interdependency matrix is presented to provide a better mapping of implementation, utilization, and in some cases a lack of integration among infrastructure systems. It is expected that this review will contribute to the advancement of the growing area of integrated infrastructure systems. Assessment of the research on integrated infrastructure modeling literature showed that the focus of most modeling efforts is mainly on short term operational purposes and extreme events. Long-term efforts to examine the impacts and assessment of future policies and scenarios are needed. Although ‘integration’ is being used in many studies on civil infrastructure, the level of detail or type of integration is not consistent and in some cases almost trivial. [ABSTRACT FROM AUTHOR]

Microplastic (MP) pollution is ubiquitous in the oceans and poses serious threats to the marine ecosystems. Nowadays numerical modeling has become one of the widely used tools for monitoring and predicting the transport and fate of MP in marine environments. Despite the growing body of research on numerical modeling of marine MP, the advantages and disadvantages of various modeling methods have not received systematic evaluation in published works. Important aspects such as parameterization schemes for MP behaviors, factors influencing MP transport, and proper configuration in beaching are essential for guiding researchers to choose proper methods in their work. For this purpose, we comprehensively reviewed the current knowledge on factors influencing MP transport, classified modeling approaches according to the governing equations, and summarized up-to-date parameterization schemes for MP behaviors. Critical factors such as vertical velocity, biofouling, degradation, fragmentation, beaching, and washing-off were reviewed in the frame of MP transport processes. [Display omitted] • Microplastic particles are widely distributed in marine environments. • Factors influencing microplastic transport processes are summarized. • Modeling approaches of microplastic transport and fate are classified. • Parameterization schemes in microplastic modeling are summarized. [ABSTRACT FROM AUTHOR]

• The characteristics of current, electric fields and modeling approaches of lightning M-component mode of charge transfer were summarized. • M-component-type ICC pulses can be distinguished from mixed-mode pulses using four different criteria. • The significance of M-components is reviewed according to practical aspects in transformer secondary, surge protective devices (SPD), grounding systems. In this paper, we present the characteristics of current, electric fields and modeling approaches of lightning M-component mode of charge transfer. We consider both the classical M-components (occurring after return strokes) and M-component-type ICC (Initial Continuous Current) pulses occurring during the initial (ICC) phase of upward flashes. M-component-type ICC pulses can be distinguished from mixed-mode pulses using different criteria: (i) the 10–90% current risetime at the channel-base with respect to an 8-µs risetime; (ii) the time lag between the onset of the current and electric fields with a respect to a threshold of 10 µs; (iii) an asymmetrical waveform coefficient (AsWc) with respect to a value of 0.8; (iv) the relative height of the junction or connection points on the grounded channel above the ground. The features of M-component electric field waveforms are summarized for close, intermediate, and far distance ranges. The observed millisecond-scale slow-part pulse shows a polarity reversal from an initial-negative waveform at close range, to a full positive-flattening late-time response at intermediate range and a bipolar wave-shape at the far distance range. One or some microsecond-scale fast pulses (junction pulse) are observed to precede the millisecond-scale slow part pulse at intermediate and far distance ranges. The microsecond-scale fast pulses are dominated by unipolar pulses along with several cases of bipolar pulses exhibiting initial polarities of both signs. The main advantage of the guided wave model and its variations is their simplicity and straightforward implementation. The guided wave model is also able to reproduce reasonably well the observed slow electric fields. The nonlinear models are more physics-based compared to the guided wave models. They are based on an important number of adjustable parameters, many of which cannot be directly inferred from experimental observations. The significance of M-components is reviewed according to practical aspects in transformer secondary, surge protective devices (SPD), grounding systems. [ABSTRACT FROM AUTHOR]

The development and application of ecosystem models in estuarine and coastal systems has grown exponentially over the past four decades. Models have become ensconced as major tools for both heuristic study of ecosystem structure and function as well as for informing management decisions, particularly with respect to cultural eutrophication. In recent years an ever-expanding toolbox of modeling approaches is being offered to complement traditional methods. This expansion of modeling in estuarine and coastal science was exemplified by four sessions devoted to modeling at the 2007 biennial conference of the Estuarine Research Federation in Providence, RI. We felt the time was right to propose a special session of Ecological Modelling to synthesize talks from these sessions to present the state of the art in coastal and estuarine modeling. The collection of papers contained in this special issue presents a diversity of traditional and novel modeling approaches, methods for assessing model validity and predictability, and the utility of models in management applications. We believe that together these papers provide an excellent overview of current approaches to modeling estuarine hydrodynamics, water quality, and ecosystem/food web dynamics, applications of complex and relatively simple modeling approaches, applications in both deep and shallow coastal systems, goals relevant for both heuristic and management applications, and perspectives based on traditional mechanistic model development as well as more recent alternative approaches. [Copyright &y& Elsevier]

Abstract: In the present paper, a three-dimensional, time-dependent SOFC numerical model is defined, considering all the phenomena occurring in each component of the fuel cell. All the equations are written in a partial differential form, thus the model is independent from the cell geometry (planar, tubular, monolithic) and the modeling approach (i.e. time-dependent, 3D, 2D). The triple-phase-boundary (TPB) is modeled as a finite region, as well as a non-dimensional interface area. In the latter case the source terms of the energy, mass and electrical conservation equations are treated as a boundary conditions. Finally, a literature review is conducted. Some results from the models previously developed by the authors or found in the literature survey are presented. Each of them can be reviewed as a simplified version of the model presented in the present paper. The simplified assumptions and the related omissions that each of those approaches imply are also analyzed. [Copyright &y& Elsevier]

• The research on modeling and managing of domino effects were reviewed. • The methods for modeling and managing domino effects were classified and analyzed. • The current research trends and the needs of the future were discussed. • This study considered domino effects caused by accident events, Natechs and attacks. Recent catastrophic accidents in China and the USA urge and justify a thorough study on current & future research trends in the development of modeling methods and protection strategies for prevention and mitigation of large-scale escalating events or so-called domino effects in the process and chemical industries. This paper firstly provides an overview of what constitutes domino effects based on the definition and features, characterizing domino effect studies according to different research issues and approaches. The modeling approaches are grouped into three types while the protection strategies are divided into five categories, followed by detailed descriptions of representative modeling approaches and management strategies in chemical plants and clusters. The current research trends in this field are obtained based on the analysis of research work on domino effects caused by accidental events, natural events, and intentional attacks over a period of the past 30 years. A comparison analysis is conducted for the current modeling approaches and management strategies to pose their applications. Finally, this paper offers future research directions and identifies critical challenges in the field, aiming at improving the safety and security of chemical industrial areas so as to prevent and mitigate domino effects. [ABSTRACT FROM AUTHOR]