Peyman BabakhaniThe University of Manchester · School of Engineering
Peyman Babakhani
PhD
About
33
Publications
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Introduction
Additional affiliations
September 2011 - June 2015
February 2014 - May 2016
February 2014 - May 2016
Education
October 2009 - July 2012
Publications
Publications (33)
The balance between the degradation and preservation of organic carbon (OC) is
vital for the modulation of atmospheric CO2 and O2 in the Earth system, which
regulates short-term climate as well as oxygenation of the early Earth. The mineral
carbon pump (MnCP) is recently proposed to describe how soil minerals enhance
the persistence and accumulatio...
As a critical component of sustainable water management, groundwater level prediction plays a vital role in mitigating droughts and ensuring adequate water supply. For decades, groundwater level dynamics have been primarily studied through physics-based models, solving partial differential equations. However, interest has increased over the past fe...
The balance between degradation and preservation of sedimentary organic carbon (OC) is important for global carbon and oxygen cycles1. The relative importance of different mechanisms and environmental conditions contributing to marine sedimentary OC preservation, however, remains unclear2,3,4,5,6,7,8. Simple organic molecules can be geopolymerized...
Despite extensive research on microplastics (MP) in marine environments, little is known about MP abundance and transport in terrestrial systems. There is, therefore, still little understanding of the main mechanisms driving the substantial transport of MP across different environmental compartments. Storm events can transport MP beyond boundaries,...
Volume 17 Issue 12, December 2022
https://www.nature.com/nnano/volumes/17/issues/12
The cover image depicts a situation where engineered nanoparticles are used to improve the efficiency and durability of ocean fertilization for CO2 capture from the atmosphere. The generated biomass sinks to store carbon in the deep ocean for centuries.
Carbon dioxide can be removed from the atmosphere by increasing the phytoplankton population in the oceans using nutrients. Life cycle assessment, cost analyses and data from previous studies reveal that engineered nanoparticles could increase the efficiency of this process and that it can be made affordable, viable, and safe for marine ecosystems.
Artificial ocean fertilization (AOF) aims to safely stimulate phytoplankton growth in the ocean and enhance carbon sequestration. AOF carbon sequestration efficiency appears lower than natural ocean fertilization processes due mainly to the low bioavailability of added nutrients, along with low export rates of AOF-produced biomass to the deep ocean...
Minerals are widely proposed to protect organic carbon (OC) from degradation and thus
promote the persistence of OC in soils and sediments, yet the link between mineral
adsorption and retardation of microbial remineralisation is often presumed and a
mechanistic understanding of the protective preservation hypothesis is lacking. Here we
show that me...
Minerals are widely proposed to protect organic carbon from degradation and thus promote the persistence of organic carbon in soils and sediments, yet a direct link between mineral adsorption and retardation of microbial remineralisation is often presumed and a mechanistic understanding of the protective preservation hypothesis is lacking. We find...
The coprecipitation of organic carbon with iron minerals is important for its preservation in soils and sediments, but the mechanisms for carbon-iron interactions and thus the controls on organic carbon cycling are far from understood. Here we coprecipitate carboxylic acids with iron (oxyhydr)oxide ferrihydrite and use near-edge X-ray absorption fi...
Reducing energy consumption in the building sector, which contributes to 30% of energy-related, global CO2 emissions, is of crucial importance in mitigating climate change. Vernacular architectural elements such as windcatchers have been a paramount model in modern sustainable architecture to provide energy-efficient cooling and ventilation using n...
In order to manage and control the pathogen release from waste streams of various municipal, industrial, and agricultural pollution sources, it is crucial to investigate the impact of release pathways of such contaminants on their fate and transport in groundwater, especially in respect to natural heterogeneities encountered in aquifers. In this la...
Greater particle mobility in subsurface environments due to larger size, known as size exclusion, has been responsible for colloid-facilitated transport of groundwater contaminants. Although size exclusion is not expected for primary engineered nanoparticles (NP), they can grow in size due to aggregation, thereby undergoing size exclusion. To inves...
Aggregation as an essential mechanism impacting nanoparticle (NP) functionality, fate, and transport in the environment is currently modelled using population-balance equation (PBE) models which are computationally expensive when combined with other continuum-scale reactive transport models. We propose a new simple mass-concentration-based, chain-r...
Environmental contamination continues to pose a serious threat to human health and the ecosystem. Over the next several decades, remediation research and business will be actively restoring both legacy and newly spilled sites in many countries worldwide. This chapter critically reviews the 20-year progress (1997–2017) in nanoscale zerovalent iron (...
Controlled emplacement of polyelectrolyte-modified NZVI at a high particle concentration (1–10 g/L) is needed for effective in situ subsurface remediation. For this reason, a modeling tool capable of predicting polyelectrolyte-modified NZVI transport is imperative. However, the deep bed filtration theory is invalid for this purpose because several...
This chapter summarizes the fundamentals of colloidal and surface science for understanding poor deliverability and mobility of bare NZVI in the subsurface for in situ remediation. The role of three factors, namely, intrinsic magnetic attraction of NZVI, high particle concentration for remedial application, and unfavorable environmental conditions,...
Nanoparticle (NP) aggregation is typically investigated in either quiescent or turbulent mixing conditions; neither is fully representative of dynamic natural environments. In groundwater, complex interacting influences of advective-diffusive transport, pore tortuosity, and the arrival of aggregates from up-gradient pores impacts the aggregation be...
Despite aggregation’s crucial role in controlling the environmental fate of nanoparticles (NP), the extent to which current models can describe the progressive stages of NP aggregation/sedimentation is still unclear. In this paper, 24 model combinations of two population-balance models (PBMs) and various collision frequency and settling velocity mo...
Environmental applications of NP increasingly result in widespread NP distribution within porous media where they are subject to various concurrent transport mechanisms including irreversible deposition, attachment/detachment (equilibrium or kinetic), agglomeration, physical straining, site-blocking, ripening, and size exclusion. Fundamental resear...
The continuing rapid expansion of industrial and consumer processes based on nanoparticles (NP) necessitates a robust model for delineating their fate and transport in groundwater. An ability to reliably specify the full parameter set for prediction of NP transport using continuum models is crucial. In this paper we report the reanalysis of a datas...
The solute transport model MODFLOW has become a standard tool in risk assessment and remediation design. However, particle transport models that take into account both particle agglomeration and deposition phenomena are far less developed. The main objective of the present study was to evaluate the feasibility of adapting the standard code MODFLOW/...
In this paper, the transport of polymer-modified nanoscale zero valent iron (NZVI) through one-dimensional (1-D) and two-dimensional (2-D) models of saturated porous media was investigated numerically and analytically. The numerical investigations were conducted for the cases, in which the agglomeration of NZVI particles was not the case, i.e., whe...
Numerical investigation of Nanoscale Zero Valent Iron transport in saturated porous media
Abstract
Nano scale Zero Valent Iron (NZVI) particles, due to high specific surface, high reactivity with pollutants, and its potential to be mobile in the subsurface, have become attractive alternative for in situ remediation of groundwater contaminants. Alth...
Numerical investigation of Nanoscale Zero Valent Iron transport in saturated porous media
Abstract
Nano scale Zero Valent Iron (NZVI) particles, due to high specific surface, high reactivity with pollutants, and its potential to be mobile in the subsurface, have become attractive alternative for in situ remediation of groundwater contaminants. Alth...
Questions
Questions (4)
I would like to know how two partial differential equations such as advection-dispersion-reaction equation and first-order kinetic mass transfer equation in contaminant transport modeling are solved together numerically. The example that I have been involved with is in the manual of MT3DMS code (Zheng and Wang, 1999), page 52. The two equations are combined into the coefficients of one matrix equation, but I cannot understand if the two partial differential equations are first merged together and then the coefficients of the matrix are obtained, why none of the parameters of the model are not eliminated, in oppose to what we expect from the merged equations?
I am going to establish the pH of montmorillonite or bentonite dispersion at a previously set ionic strength (e.g., 5 mM NaClO4) in order to study their aggregation subsequently over a period of several days. However, once I adjust the pH with 0.1 M HCl/NaOH, immediately afterwards it changes, e.g., from 8 to 7.5 within a few minutes in the case of montmorillonite, or from 9, 7 and 5 to 8.3, 7.6, and 6.4, respectively, within several days in the case of bentonite.
The use of standard buffer solutions may not be appropriate for these experiments, since the buffer solution can change the surface characteristics of colloids as well as having no significance to the real environment.
I would highly appreciate it if somebody could suggest a simple and fast way to maintain the pH for this kind of experiment.
