bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quorum Quenching for Biofouling Control in Membrane Bioreactors
Authors: Yavuztürk Gül Bahar , Köse Mutlu Börte , Park Pyung‐Kyu , Lee Chung‐Hak , Koyuncu Ismail 
Published: December 2019

Abstract
In today's World, the recovery, reuse, and recycling of water turn heads more with the continuing water scarcity, and this requires a development of conventional wastewater treatment technologies. Membrane bioreactors (MBRs) can provide many advantages over the conventional activated sludge systems. However, biofouling problem restricts the potential widespread application of MBRs. The main reason for this is the increase in the operating costs. Nowadays, there are much research to elucidate and control the membrane fouling in MBR. In fact, it is difficult to find an effective solution for biofouling problem without heading toward to biological concepts, because the biomass matrix is significantly complex and includes various living microorganisms. Quorum quenching (QQ) mechanism aims to prevent the signaling for communication and group behaviors. For the last five years, the development of antibiofouling strategies based on QQ in MBRs has been a relatively hot topic in biofouling research. QQ is a natural process which is not harmful to the environment. Therefore, unquestionably, studies on QQ in MBR represent a promising alternative for controlling biofouling for future applications. This article explains the quorum sensing (QS) and QQ concepts and presents various and highly successful examples for enzymatic, bacterial, and fungal QQ MBR operations.
Light Transmission Spectroscopy
Authors: Tanner Carol E. , Ruggiero Steven T. 
Published: December 2019

Abstract
Light Transmission Spectroscopy (LTS) is a recently developed technique for measuring the diameter and concentration of nanoparticles in fluid suspension. LTS is based on obtaining the optical extinction of light as a function of wavelength, over the range of ∼220–1100 nm, and using Mie theory to transform extinction information into a particle‐size distribution. This has been made practical with recent developments in compact, high resolution optical spectrometers and “lap‐top” computing. LTS has a particle diameter measurement range of ∼1–3000 nm. LTS has a large dynamic range, with an ultimate concentration range covering several orders of magnitude. The technique is most applicable to relatively dilute samples, with a minimum detection concentration of ∼1000 objects/mL. LTS has evolved from a laser‐based laboratory instrument to a transportable format with a modest bench‐top footprint. The system has proven itself especially useful to biological‐type investigations involving objects ranging in size from proteins to bacteria – and has even been adapted to detect species‐specific environmental DNA. A special feature of the technique is its ability to perform optical subtraction, whereby objects of a given size and concentration in a reference channel can effectively eliminate their optical contribution in a sample‐measurement channel.
Measurement of Chromium Species in Water Samples
Authors: Furdui Vasile I. , Mädler Stefanie 
Published: December 2019

AbstractWhile trivalent chromium (Cr(III)) is an essential nutrient, hexavalent chromium (Cr(VI)) is a human carcinogen and genotoxic. In evaluation of the toxicological risks and environmental impacts, the separate analysis of Cr(III) and Cr(VI) in water samples provides more information than the analysis of total Cr. The relatively high instability of the Cr species in natural water samples further complicates the analysis, requiring preservation or other advanced procedures. This article is intended to present the broad range of available separation methods for Cr analysis, discussing the possible interferences, detection limits, and preserving options. The intense color complex formed between dichromate ions and 1,5‐diphenylcarbazide (DPC) is used for Cr(VI) measurement in spectrophotometric, flow injection analysis (FIA), ion chromatography (IC), liquid chromatography (LC), capillary electrophoresis (CE), and electrochemical methods. Atomic spectrometry, molecular spectrometry, and other methods are also discussed. An absolute analysis with accurate measurement of Cr(VI) at the time of sample collection can be achieved with speciated isotope dilution mass spectrometry (SIDMS) by using LC separation coupled to the inductively coupled plasma mass spectrometry (ICP‐MS) or IC separation coupled to electrospray ionization tandem mass spectrometry (ESI‐MS/MS).
Fundamental Hydrologic Equations
Authors: Beckie Roger 
Published: December 2019

Abstract
The principles of mass, momentum and energy conservation are fundamental to quantitative hydrology. Physically based models in hydrology respect these principles, in contrast to many statistical models, which may not. These conservation principles are most clearly expressed when written as mathematical equations. One may view mathematics as a “grammar” and “language” to communicate the “literature” of physical principles. In this chapter, we shall therefore focus mostly upon the mathematical development of the conservation principles and their manifestation in hydrology. In this way, we hope that our development will give physical meaning to the fundamental hydrologic equations. We will assume that reader has an elementary understanding of multivariate calculus and differential equations.
We first state the fundamental principles and then outline the general ways that mathematical expressions for these principles are formulated. We then develop general mathematical equations for each principle for the specific case of a flowing fluid, which in hydrology is usually water. These general equations are typically then used as the basis for expressions used in hydrology. We conclude the chapter with a sequence of examples from hydrology to show how the principles are manifest in expressions that describe hydrologic processes.
Oil and Gas Produced Water, High‐Salinity Brines, and Associated Cost Modeling
Authors: Sullivan Graham Enid J. 
Published: December 2019

Abstract

Produced water (PW) is a large‐volume waste product from the oil and gas industry. Converting this waste into a resource requires system models to optimize treatment designs, transportation, and storage costs. Five models are presented and evaluated for their capabilities. All the models fall within the AACEI Level 5 standard for preliminary evaluation uses, with cost accuracies of ±30%. Three databases that contain useful geospatial data that could improve model results are presented and described. The USGS PW database is the most comprehensive of the group. Most PW data, for both volume and chemistry, has problems with incompleteness, inaccuracies, and lack of correlation from state to state. Model improvements that are needed include the following:

Application of correct desalination processes to varying ranges of salt content and different PW types.

Use of appropriate organic removal technologies.

Inclusion of up‐to‐date cost indices.

Clear graphical results and flow diagrams; energy usage at each step, pumping parameters, energy recovery opportunities, and water and waste stream flows.

Costs output for each step and for the whole system with improved accuracy.

Indications of the output water quality.

Ability to evaluate toxicity of trace constituents.

Linkages with real data sets and GIS.

Ongoing support/funding for maintenance and upgrades.

Feedback loops to validate results with proven field data.

Common computing platforms for model development and evolution.
Applications of Stable Isotopes to Studies of Paleohydrology and Paleoclimatology
Authors: Xia Zhengyu , Yu Zicheng 
Published: December 2019

Abstract
Stable isotope ratios of hydrogen and oxygen in water vary as a function of hydrological processes and environmental conditions. Water isotopic composition preserved in ice cores, and other geological and biological archives have been used as hydrological tracers and climate proxies to study past climate and hydrological changes. We provide a brief overview on the principles and mechanisms of water isotope proxies and on the major contributions of stable isotope techniques to the studies of paleohydrology and paleoclimatology. In oceans, oxygen isotopes of foraminifera in deep‐sea sediments continuously document long‐term history of global ice volumes and ocean temperature from Cenozoic greenhouse to icehouse and through the Quaternary glacial–interglacial cycles. On continents, isotopic composition of meteoric water is influenced by multiple parameters, including air temperature, precipitation amount, air mass history, and atmospheric circulation pattern. The use of water isotope proxies in various archives reveals multifaceted continental climate changes on orbital, millennial, and centennial scales. In addition, isotope proxies in annual growth layers of corals and other biological archives further resolve past short‐term climate variability. Overall, these studies broaden our understandings of the global climate histories and forcing mechanisms and provide benchmarks to project future environmental changes.
The Food–Water–Energy Nexus in Chile: Agriculture, Water Companies, and Mining
Authors: Arce G. , Gironás J. , Molinos‐Senante M. , Suárez F. , Pastén P. , Meza F. , Donoso G. , Vicuña S. , Vargas I. 
Published: December 2019

Abstract
Water, food, and energy (WFE) are critical resources that are intimately linked, as their production requires the other resources as input and changes impacting one of these resources can affect the others as well. For this reason, the WFE nexus concept was coined in order to represent this inextricable connection. In addition to the demands between these resources, external stressors can exert additional demands. In the Chilean case, urban population growth, mining, agriculture, and climate change emerge as relevant drivers of the WFE nexus status. The effect of these drivers are discussed and illustrated through the analysis of the current and future WFE nexus status in four different Chilean basins (Antofagasta, Copiapó, Maipo, and Maule), which represent a sample of WFE nexus problems. Several challenges imposed by these drivers in the Chilean context are presented, along with opportunities to address them, such as the implementation of alternative technologies, resource management strategies, and methodologies for decision‐making.
Deoxygenation of the Open Oceans and its Consequences
Authors: Kirchman David L. 
Published: December 2019

AbstractDeoxygenation or loss of dissolved oxygen (O2) from the open oceans is caused by higher temperatures, changes in circulation and stratification, and alteration of biological processes, all ultimately due to increasing atmospheric carbon dioxide (CO2) and other greenhouse gases. Coastal waters are also losing O2because of excess nutrients from terrestrial runoff. Deoxygenation and the spreading of oxygen minimum zones seem to have already caused the geographical range of hypoxia‐tolerant organisms to expand whereas it has curtailed the oceanic regions inhabitable (habitat compression) by other organisms sensitive to even slight decreases in O2concentrations. Benthic organisms and demersal fish are negatively affected by the unprecedented shoaling of deep, low O2waters into shallow coastal areas. Deoxygenation also impinges on critical steps in several biogeochemical cycles, such as the production of two nitrogenous gases, N2and nitrous oxide (N2O), during nitrification, denitrification, and anaerobic ammonium oxidation. Loss of N via the two gases could limit biological production in the oceans, which may lead to less deoxygenation, while release of N2O, a potent greenhouse gas, could lead to more deoxygenation. Along with warming temperatures, increasing dissolved CO2, and higher acidity, deoxygenation is likely to continue in the future with many consequences for oceanic biota and biogeochemistry.
Hybrid Ion Exchange Nanotechnology (HIX‐Nanotech)
Authors: German Michael , SenGupta Arup K. 
Published: December 2019

Abstract
From a physical‐chemical viewpoint, every polymeric ion exchange resin bead is a crosslinked polyelectrolyte that is insoluble in water. Today, tens of ion exchange resin manufacturers around the world produce hundreds of different products. As different as they may appear, these ion exchangers are well defined and the specific interactions are well characterized by five independent composition variables, namely, matrix, functionality, crosslinking, pore structure and physical configuration. In addition to the diverse groups of ion exchangers characterized by these five composition variables, a new class of polymeric‐inorganic ion exchangers has been synthesized. Here, a dispersed phase of metal or metal oxide nanoparticles (MNPs or MONPs) is embedded in the ion exchanger phase; together they offer a synergy not available otherwise. The resulting new materials are heterogeneous, even at the sub‐10 nm scale, and termed “Hybrid Ion Exchangers” or HIX. In such a material, the host (i.e. polymer beads) improves the hydraulic permeability in the flow‐through systems with no apparent influence on the behavior of the metal and metal oxide nanoparticles. This article emphasizes how the choice of the functional groups of the polymeric host materials can be harnessed to alter (enhance or diminish) the intrinsic properties of the nanomaterials.
Application ofShewanellato Water Treatment Issues
Authors: Szeinbaum Nadia , Toporek Yael J. , Shin Hyun‐Dong , DiChristina Thomas J. 
Published: December 2019

AbstractShewanella drives a variety of environmentally important processes, including the biogeochemical cycling of carbon, metals, metalloids, and radionuclides. The ability of Shewanella to deliver electrons extracellularly also renders this genus valuable for applications of contaminant remediation and energy generation in water treatment processes. Although the first Shewanella species was isolated and studied as a model metal‐reducing microorganism over thirty years ago, only recently has research focused on employing Shewanella to drive water treatment processes. This article examines current and prospective applications of Shewanella to water treatment issues, highlighting biochemical details associated with each technology. The technologies include the remediation of metal‐contaminated environments, the generation of electricity from wastewater streams, the removal of hazardous contaminants under anaerobic conditions, and precious metal recovery in combination with formation of novel biocatalysts.
Geochemistry of Urban Water Systems
Authors: Lyons W. Berry , Gardner Christopher B. 
Published: December 2019

Abstract
The complex infrastructure and concentrated humasn activities in urban areas greatly affect the distribution of both water and elements in and around urban aquatic environments. Unlike more “natural” systems, the ecological, hydrological, and geochemical footprints of cities are much greater than the area of the city itself. In addition, cities themselves are diverse – a city's age, size, climate, building materials, stage of economic development, legacy of previous land uses, and environmental best management practices all exert influence over water quantity and quality. Within any individual urban area, land use and infrastructure age are heterogeneous, and pollution in the aquatic environment can occur both from point‐sources (e.g., wastewater effluent, construction, spills, long‐term leakage) and nonpoint sources (e.g., stormwater runoff). All of these factors combine to alter hydrologic systems and enhance chemical fluxes in urban areas. Only recently have urban systems become the focus of their own, unified approach to investigation within the environmental sciences. In this article, we discuss some of the issues that confound the understanding of the geochemistry of urban aquatic systems, including the impact of impervious surfaces, the effects of heterogeneity of land cover on water quality, and how urban areas function as “global” water polluters.
Reorienting Watershed Management as a Climate Change Adaptation Strategy
Authors: Ratna Reddy V. , Chiranjeevi T. 
Published: December 2019

AbstractThis article aims to assess what it takes (beyond current measures) to make watershed management (WSM) a mitigation or adaptation strategy to deal with climate change impacts. This article draws on the existing literature on WSM with respect to its design, implementation, and impacts on agriculture and community livelihoods. As WSM has evolved over the years as a livelihood strategy in the developing countries of Asia/Africa, this article is confined mainly to experiences from India with broad implications for countries of Asia and Africa. WSM in its present form is necessary but not sufficient to strengthen the resilience of agroecological systems in the context of climate change. Apart from adopting a more scientific and integrated approach toward designing and implementing, WSM could be transformed into a climate change adaptation strategy by integrating additional farm management methods into its package of practices. These include access to climate information at the village level, sustainable groundwater management, access to appropriate farm machinery, judicious input mix, land use, and cropping patterns. In addition, policy directions are provided for making WSM climate resilient.
Manganese Cycling in the Oceans
Authors: Tebo Bradley M. , Luther George W. 
Published: December 2019

AbstractManganese (Mn) is an essential element for life. Although its concentration is at (sub)nanomolar levels throughout the ocean, it affects the oxygen concentration of the ocean because it is central to the photosynthetic formation of dioxygen, O2, in photosystem center II. Mn inputs into the ocean are from atmospheric transport of particles and their dissolution to form dissolved Mn, and from the flux of dissolved Mn from rivers, sediments, and hydrothermal vents. The main removal mechanism is transport of particulate Mn from dust and organic matter to the sediments. The environmental chemistry of manganese centers on its +2, +3, and +4 oxidation states. Most recent data show that Mn(II) is dissolved, that Mn(IV) is particulate MnO2, and that Mn(III) can be particulate or dissolved when bound to organic complexes [denoted as Mn(III)‐L]. Mn(II) is oxidized primarily by microbial processes whereas MnO2is reduced by abiotic and biotic processes. Photochemical processing aids redox cycling in surface waters. In suboxic zones, which are defined as areas where both dissolved O2and H2S concentrations are below 3 μM, both oxidation and reduction processes can occur but usually at different depths. In suboxic zones, dissolved Mn is also released from organic matter during its decomposition and from MnO2reduction.
Horizontal Wells
Authors: Russell David L. 
Published: December 2019

Abstract
The design and operation of horizontal wells are often misunderstood. While well screen is an accepted practice for vertical wells, the well screen has a very large open area and is not suited to the desired flow manipulation in the aquifer. This article attempts to explain an effective technique for designing efficient horizontal wells in collection or remedial situations for uniform collection of fluids (oil and water), uniform injection of fluids into the aquifer, or uniform injection or collection of gases into an aquifer.
Colloid Transport in Environmental Granular Porous Media
Authors: Johnson William P. , Ma Huilian , Rasmuson Anna , VanNess Kurt , Li Ke , Ron Cesar , Erickson Brock 
Published: December 2019

AbstractColloids are nano‐ to micro‐sized particles (biological and nonbiological) suspended in water. They are important as contaminants (e.g. pathogens), or carriers of contaminants (e.g. dissolved organic matter or clays) in water, as well as in a multitude of other contexts ranging from subsurface cleanup of hazardous waste (e.g. nano zero valent iron) to drug delivery in biological systems. The above contexts all involve colloid transport in porous media, wherein a complex set of physical and chemical interactions act on colloids. These interactions originate at the nanoscale and propagate to the field scale, leading to complex transport behaviors that are difficult to predict even following several decades of research on this topic. In this article, we provide a conceptual description of these interactions and impacts. The physical transport processes governing colloid transport are reviewed, culminating in predictions of pore‐scale transport behavior that are upscaled to predictions of transport at the field scale. A major impediment to prediction has been the complexity of interactions when colloids and collectors (porous media grains) are both negatively charged, leading to repulsion between them. We review strategies to recognize the nanoscale heterogeneity that allows colloid attachment despite overall repulsion, as well as the influence of nonspherical shape on their transport.
Sonochemical Remediation of Pollutants in Soils and Sediments
Authors: Fagan William P. , Weavers Linda K. 
Published: December 2019

AbstractUltrasonic treatment serves as an alternative and/or complementary remediation technology for contaminated soils and sediments in comparison to traditional methods, such as dredging andin situcapping. Ultrasonic waves of alternating rarefaction and compression cycles create cavitation bubbles over the course of microseconds. Cavitational collapse produces enormous temperatures and pressures that initiate thermolysis of water and subsequent radical oxidation. Physical effects of ultrasound increase mass transfer rates, whether it be via desorption/dissolution of contaminants or solute transport in porous media. Both of these processes are integral in remediation. Desorption and dissolution ensure that contaminants are available for reaction in the aqueous phase. Increased solute transport by ultrasound enhances amendment delivery to contaminated sites. The purpose of this article is to describe both the potential for and challenges of utilizing ultrasound as a remediation technology. Much of this knowledge has been laid by the literature exploring the sonochemical effects on pollutants in bench‐scale sediment slurries. Both bench‐scale ultrasonic studies on remediation of contaminated soils and sediments and enhanced oil recovery using ultrasound have provided both mechanistic understandings and insights for pilot‐scale systems. Although challenges exist in scaled‐up systems, ultrasound is a multifunctional treatment technology with unique features compared to other remediation technologies.
Extreme Events and Their Impacts – Managing Environmental Risk
Authors: Russell David L. 
Published: December 2019

Abstract

In the environmental field, we focus on prevention, treatment, and cleanup of residuals, and worker safety but often fail to recognize, nor discuss the subject of risk from our operations, facilities, and practices. This article discusses risk, its presentation, analysis, and methods to identify and quantify both project risk and individual risk from a variety of potential sources. Inherent in any operating facility or ongoing activity is risk: risk from fire, risk from explosion, external risks, internal risks, weather etc. – all of which can be devastating on employees, neighbors, equipment, and the environment. This article also introduces demonstrated risk management techniques that have been successfully used in industry and by NASA.
Fault tree analysis
(FTA) and Risk‐Informed Decision Management (RIDM) techniques can improve operational safety and improve decision‐making. RIDM may be too complex for small projects, FTA can be applied simply and effectively, and this article discusses the principles behind each analytical technique and provides references for further investigation and application.