bluuebunny/crossref_metadata_2025_split huggingface dataset:
Observations of Energetic-particle Population Enhancements along Intermittent Structures near the Sun from the Parker Solar Probe
Authors: Bandyopadhyay Riddhi , Matthaeus W. H. , Parashar T. N. , Chhiber R. , Ruffolo D. , Goldstein M. L. , Maruca B. A. , Chasapis A. , Qudsi R. , McComas D. J. , Christian E. R. , Szalay J. R. , Joyce C. J. , Giacalone J. , Schwadron N. A. , Mitchell D. G. , Hill M. E. , Wiedenbeck M. E. , McNutt R. L. , Desai M. I. , Bale Stuart D. , Bonnell J. W. , de Wit Thierry Dudok , Goetz Keith , Harvey Peter R. , MacDowall Robert J. , Malaspina David M. , Pulupa Marc , Velli M. , Kasper J. C. , Korreck K. E. , Stevens M. , Case A. W. , Raouafi N. 
Published: February 2020

Abstract
Observations at 1 au have confirmed that enhancements in measured energetic-particle (EP) fluxes are statistically associated with “rough” magnetic fields, i.e., fields with atypically large spatial derivatives or increments, as measured by the Partial Variance of Increments (PVI) method. One way to interpret this observation is as an association of the EPs with trapping or channeling within magnetic flux tubes, possibly near their boundaries. However, it remains unclear whether this association is a transport or local effect; i.e., the particles might have been energized at a distant location, perhaps by shocks or reconnection, or they might experience local energization or re-acceleration. The Parker Solar Probe (PSP), even in its first two orbits, offers a unique opportunity to study this statistical correlation closer to the corona. As a first step, we analyze the separate correlation properties of the EPs measured by the Integrated Science Investigation of the Sun (IS⊙IS) instruments during the first solar encounter. The distribution of time intervals between a specific type of event, i.e., the waiting time, can indicate the nature of the underlying process. We find that the IS⊙IS observations show a power-law distribution of waiting times, indicating a correlated (non-Poisson) distribution. Analysis of low-energy (∼15 – 200 keV/nuc) IS⊙IS data suggests that the results are consistent with the 1 au studies, although we find hints of some unexpected behavior. A more complete understanding of these statistical distributions will provide valuable insights into the origin and propagation of solar EPs, a picture that should become clear with future PSP orbits.
Small, Low-energy, Dispersive Solar Energetic Particle Events Observed by Parker Solar Probe
Authors: Hill M. E. , Mitchell D. G. , Allen R. C. , de Nolfo G. A. , Vourlidas A. , Brown L. E. , Jones S. I. , McComas D. J. , McNutt R. L. , Mitchell J. G. , Szalay J. R. , Wallace S. , Arge C. N. , Christian E. R. , Cohen C. M. S. , Crew A. B. , Desai M. I. , Giacalone J. , Henney C. J. , Joyce C. J. , Krimigis S. M. , Leske R. A. , Mewaldt R. A. , Nelson K. S. , Roelof E. C. , Schwadron N. A. , Wiedenbeck M. E. 
Published: February 2020

Abstract
The Energetic Particle Instrument–Low Energy (EPI-Lo) experiment has detected several weak, low-energy (∼30–300 keV nucleon–1) solar energetic particle (SEP) events during its first two closest approaches to the Sun, providing a unique opportunity to explore the sources of low-energy particle acceleration. As part of the Parker Solar Probe (PSP) Integrated Science Investigation of the Sun (IS⊙IS) suite, EPI-Lo was designed to investigate the physics of energetic particles; however, in the special lowest-energy “time-of-flight only” product used in this study, it also responds to solar photons in a subset of approximately sunward-looking apertures lacking special light-attenuating foils. During the first three perihelia, in a frame rotating with the Sun, PSP undergoes retrograde motion, covering a 17° heliographic longitudinal range three times during the course of the ∼11-day perihelion passes, permitting a unique spatial and temporal study into the location, correlation, and persistence of previously unmeasurable SEPs. We examine the signatures of these SEPs (during the first PSP perihelion pass only) and the connection to possible solar sources using remote observations from the Solar Dynamics Observatory (SDO), the Solar TErrestrial RElations Observatory (STEREO), and the ground-based Global Oscillation Network Group (GONG). The orientation of the Sun relative to STEREO, SDO, and GONG makes such identifications challenging, but we do have several candidates, including an equatorial coronal hole at a Carrington longitude of ∼335°. To analyze observations from EPI-Lo, which is a new type of particle instrument, we examine instrumental effects and provide a preliminary separation of the ion signal from the photon background.
Measures of Scale-dependent Alfvénicity in the First PSP Solar Encounter
Authors: Parashar T. N. , Goldstein M. L. , Maruca B. A. , Matthaeus W. H. , Ruffolo D. , Bandyopadhyay R. , Chhiber R. , Chasapis A. , Qudsi R. , Vech D. , Roberts D. A. , Bale S. D. , Bonnell J. W. , de Wit T. Dudok , Goetz K. , Harvey P. R. , MacDowall R. J. , Malaspina D. , Pulupa M. , Kasper J. C. , Korreck K. E. , Case A. W. , Stevens M. , Whittlesey P. , Larson D. , Livi R. , Velli M. , Raouafi N. 
Published: February 2020

Abstract
The solar wind shows periods of highly Alfvénic activity, where velocity fluctuations and magnetic fluctuations are aligned or antialigned with each other. It is generally agreed that solar wind plasma velocity and magnetic field fluctuations observed by the Parker Solar Probe (PSP) during the first encounter are mostly highly Alfvénic. However, quantitative measures of Alfvénicity are needed to understand how the characterization of these fluctuations compares with standard measures from prior missions in the inner and outer heliosphere, in fast wind and slow wind, and at high and low latitudes. To investigate this issue, we employ several measures to quantify the extent of Alfvénicity—the Alfvén ratio r
A, the normalized cross helicity σ

c
, the normalized residual energy σ

r
, and the cosine of angle between velocity and magnetic fluctuations

. We show that despite the overall impression that the Alfvénicity is large in the solar wind sampled by PSP during the first encounter, during some intervals the cross helicity starts decreasing at very large scales. These length scales (often >1000d

i
) are well inside inertial range, and therefore, the suppression of cross helicity at these scales cannot be attributed to kinetic physics. This drop at large scales could potentially be explained by large scale shears present in the inner heliosphere sampled by PSP. In some cases, despite the cross helicity being constant down to the noise floor, the residual energy decreases with scale in the inertial range. These results suggest that it is important to consider all these measures to quantify Alfvénicity.
Density Fluctuations in the Solar Wind Based on Type III Radio Bursts Observed by Parker Solar Probe
Authors: Krupar Vratislav , Szabo Adam , Maksimovic Milan , Kruparova Oksana , Kontar Eduard P. , Balmaceda Laura A. , Bonnin Xavier , Bale Stuart D. , Pulupa Marc , Malaspina David M. , Bonnell John W. , Harvey Peter R. , Goetz Keith , Dudok de Wit Thierry , MacDowall Robert J. , Kasper Justin C. , Case Anthony W. , Korreck Kelly E. , Larson Davin E. , Livi Roberto , Stevens Michael L. , Whittlesey Phyllis L. , Hegedus Alexander M. 
Published: February 2020

Abstract
Radio waves are strongly scattered in the solar wind, so that their apparent sources seem to be considerably larger and shifted than the actual ones. Since the scattering depends on the spectrum of density turbulence, a better understanding of the radio wave propagation provides indirect information on the relative density fluctuations,

, at the effective turbulence scale length. Here, we analyzed 30 type III bursts detected by Parker Solar Probe (PSP). For the first time, we retrieved type III burst decay times,

, between 1 and 10 MHz thanks to an unparalleled temporal resolution of PSP. We observed a significant deviation in a power-law slope for frequencies above 1 MHz when compared to previous measurements below 1 MHz by the twin-spacecraft Solar TErrestrial RElations Observatory (STEREO) mission. We note that altitudes of radio bursts generated at 1 MHz roughly coincide with an expected location of the Alfvén point, where the solar wind becomes super-Alfvénic. By comparing PSP observations and Monte Carlo simulations, we predict relative density fluctuations, ϵ, at the effective turbulence scale length at radial distances between 2.5 and 14

to range from 0.22 to 0.09. Finally, we calculated relative density fluctuations, ϵ, measured in situ by PSP at a radial distance from the Sun of 35.7

during perihelion #1, and perihelion #2 to be 0.07 and 0.06, respectively. It is in a very good agreement with previous STEREO predictions (

) obtained by remote measurements of radio sources generated at this radial distance.
Carbon Chain Depletion of 2I/Borisov
Authors: Kareta Theodore , Andrews Jennifer , Noonan John W. , Harris Walter M. , Smith Nathan , O’Brien Patrick , Sharkey Benjamin N. L. , Reddy Vishnu , Springmann Alessondra , Lejoly Cassandra , Volk Kathryn , Conrad Albert , Veillet Christian 
Published: February 2020

Abstract
The composition of comets in the solar system comes in multiple groups thought to encode information about their formation in different regions of the outer protosolar disk. The recent discovery of the second interstellar object, 2I/Borisov, allows for spectroscopic investigations into its gas content and a preliminary classification of it within the solar system comet taxonomies to test the applicability of planetesimal formation models to other stellar systems. We present spectroscopic and imaging observations from 2019 September 20 through October 26 from the Bok, MMT telescope (formerly the Multiple Mirror Telescope, Mount Hopkins, Arizona), and Large Binocular Telescopes. We identify CN in the comet’s spectrum and set precise upper limits on the abundance of C2 on all dates in October. We use a Haser model to convert our integrated fluxes to production rates and find Q(CN) = (1.1–1.9) ∗ 1024 mols s−1 increasing over 2019 October 1 to 26, consistent with contemporaneous observations. We set our lowest upper limit on a C2 production rate, Q(C2) < 1.6 ∗ 1023 mols s−1 on 2019 October 10. The measured upper limit ratio for that date Q(C2)/Q(CN) < 0.1 indicates that 2I/Borisov is strongly in the (carbon-chain) “depleted” taxonomic group if there is any C2 production at all. Most “depleted” comets are Jupiter-family comets (JFCs), perhaps indicating a similarity in formation conditions between the most depleted of the JFCs and 2I/Borisov. More work is needed to understand the applicability of our knowledge of solar system comet taxonomies onto interstellar objects and we discuss future work that could help to clarify the usefulness of the approach.
Satisfiability in Big Boolean Algebras via Boolean-Equation Solving
Authors: Ali M. Ali Rushdi Ali M. Ali Rushdi 
Published: February 2020

This paper studies Satisfiability (SAT) in finite atomic Boolean algebras larger than the two-valued one B2, which are
named big Boolean algebras. Unlike the formula ݃(ࢄ (in the SAT problem over B2, which is either satisfiable or unsatisfiable, this
formula for the SAT problem over a big Boolean algebra could be unconditionally satisfiable, conditionally satisfiable, or unsatisfiable
depending on the nature of the consistency condition of the Boolean equation	{݃(ࢄ = (1}, since this condition could be an identity, a
genuine equation, or a contradiction. The paper handles this latter SAT problem by using a conventional method and a novel one for
deriving parametric general solutions, and subsequently utilizing expansion trees for generating all particular solutions of the
aforementioned Boolean equation. Each of these two methods could be cast in pure algebraic form, but becomes much easier to
visualize and comprehend when presented via the natural map of a big Boolean algebra, which (for historical reasons) is called the
variable-entered Karnaugh map (VEKM). In the classical method, the number of parameters used is minimized and compact solutions
are obtained. However, the parameters belong to the underlying big Boolean algebra. By contrast, the novel method does not attempt
to minimize the number of parameters used, as it uses independent parameters belonging to the two-valued Boolean algebra B2 for
each asserted atom in the Boole-Shannon expansion of the formula	݃(ࢄ .(Though the method produces non-compact expressions, it is
much quicker in generating particular solutions. The two methods are demonstrated via two detailed examples.
Cultivating Citizen Readers: Clemence Dane’s Historical Essays in Good Housekeeping
Authors: Deen Stella 
Published: February 2020

ABSTRACT
Clemence Dane’s interwar book pages for Good Housekeeping promote women’s reading history and reading across historical periods; they cultivate reader citizens poised to increase their agency in interwar cultural, professional, and public spheres. Good Housekeeping in the 1920s routinely published the views and experiences of prominent and accomplished women; and Dane’s book essays exemplify feminist periodical writers’ confidence in newly enfranchised women, whose citizenship Dane extended to the stewardship of good books.
Geochemistry of Acid Mine Waters
Authors: Nordstrom D. Kirk , Alpers C.N. 
Published: February 2020

Abstract
There are about a dozen major hydrogeochemical processes that can account for the chemical composition of most natural waters. One of these is the oxidation of pyrite, a process at least as important a source of sulfate in natural waters as seawater and sea spray, gypsum dissolution, and atmospheric emissions. The natural process of pyrite oxidation is fundamental to the supergene alteration of ore deposits, the formation of acid-sulfate soils, and the development of acidity and metal mobilization in natural waters. As mineral deposits continue to be mined, and inactive or abandoned mines with their associated waste-rock and tailings piles continue to be exposed to weathering, large concentrations of sulfate and heavy metals will continue to be found in both surface waters and ground waters. Nearly 5 × 1010 tons of mining and mineral processing wastes had been generated in the United States as of 1985 and about 109 tons continue to be generated each year (U.S. Environmental Protection Agency, 1985). A more recent estimate indicates that there may be more than 500,000 inactive or abandoned mine sites in the U.S. (Lyon et al., 1993). Hazardous mine sites in serious need of remediation are probably much fewer but may still range in the thousands. Inventories of mineral resources, mine sites, and their associated environmental hazards are being assembled at various scales by federal and state agencies to better assess the magnitude of the problem.
Metal Sorption on Mineral Surfaces
Authors: Smith Kathleen S. 
Published: February 2020

Abstract
Sorption reactions, involving both inorganic and organic particulates, are an important control on the transport and fate of many trace elements in natural systems. Understanding the controls on trace-element concentrations in waters is critical for a number of applications including the transport of contaminants and nutrients, geochemical prospecting, agriculture, municipal and industrial water treatment, and bioavailability to name a few. This chapter provides an overview of metal sorption on mineral surfaces and gives examples of predictive modeling of metal- sorption reactions in mine-drainage systems.
The word “sorption” is a general term that describes removal of a solute from solution to a contiguous solid phase and is used when the specific removal mechanism is not known. “Sorbate” or “adsorbate” refers to the solute that sorbs on the solid phase. “Sorbent” or “adsorbent” is the solid phase or substrate onto which the sorbate sorbs. “Adsorption” refers to the two-dimensional accumulation of an adsorbate at a solid surface. In the case of “surface precipitation,” there is a three-dimensional accumulation of sorbate at the solid surface. The term “absorption” is used when there is diffusion of the sorbate into the solid phase. Absorption processes usually show a significant time dependency. Sposito (1986) and Jenne (1998) provide a more detailed description of these terms. In this chapter, the term adsorption is used when describing laboratory studies with simple, well-characterized systems, and when discussing models that have been developed to describe adsorption phenomena.
Field Methods for Sampling and Analysis of Environmental Samples for Unstable and Selected Stable Constituents
Authors: Ficklin W.H. , Mosier E.L. 
Published: February 2020

Abstract
Water is an important agent in the chemical weathering of mineral deposits, mine tailings, waste rock, settling ponds and landfills, and in the dispersion of contaminants from these sources into the aquatic environment. The vast numbers of possible mineral assemblages and the complex chemical reactions that accompany mineral-water interactions result in a limitless variety of fluid compositions. For example, the variability in compositions of mine-drainage waters from a variety of active and inactive metal mines with diverse geologic characteristics are listed in Table 12.1.
In assessing water-quality characteristics, considerable care must be administered during the collection, preservation, and analysis of water samples. Analytical results from an improperly collected sample are at best questionable and at worst worthless. An excellent manual that documents field data collection and analysis procedures used by the U.S. Geological Survey (USGS) for water and fluvial sediments has been published by Fishman and Friedman (1989). Other equally authoritative manuals on water analysis are available (American Society for Testing and Materials, 1992; American Public Health Association et al., 1992; United States Environmental Protection Agency, 1983). The purpose of this chapter is to describe a number of field sampling and analysis techniques that are commonly used in acid-mine drainage and related mining-environmental water studies. Many of the techniques described here are for on-site measurements; others are for analysis of selected constituents that can be determined in the field, but that are more practically determined in the laboratory. For each method given, the general points covered are application, principle of the method, apparatus and reagents required, and a detailed description of the method including interferences, sample collection and preservation protocol, and reporting units and significant figures.
The Hydrogeochemistry of a Nickel-Mine Tailings Impoundment—Copper Cliff, Ontario
Authors: Coggans C.J. , Blowes D.W. , Robertson W.D. , Jambor J.L. 
Published: February 2020

Abstract
The Copper Cliff tailings disposal area near the town of Copper Cliff, Ontario (Fig. 21.1) has been used continuously since 1936 and constitutes one of the largest mine disposal areas in the world. The six tailings impoundments within the disposal area cover 21 km2, accounting for more than 10% of all sulfide mine tailings in Canada (Feasby et al., 1991).
Approximately 35,000 t/day of ore from the Sudbury Igneous Complex, a fine-to-medium-grained noritic to gabbroic rock locally containing up to 60 wt% sulfides, is mined by INCO Ltd. and processed at the Copper Cliff mill. Monoclinic and hexagonal pyrrhotite (Fe1-xS), pentlandite ((Ni,Fe)9S8), chalcopyrite (CuFeS2), pyrite (FeS2), and cubanite (CuFe2S3) comprise the bulk of the sulfides. Minor concentrations of cobalite (CoAsS), nickelite (NiAs), galena (PbS), and millerite (NiS) are present (Hawley and Stanton, 1962; Naldrett, 1984). Approximately 95% of the copper and 80% of the nickel are recovered in the milling process, and the remainder is discharged to the impoundments with the bulk tailings (INCO Ltd. staff, personal commun., 1991).
Natural Attenuation of Acidic Drainage from Sulfidic Tailings at a Site in Washington State
Authors: Lambeth R.H. 
Published: February 2020

Abstract
Ground and surface water can be contaminated by the transport of soluble oxidation products from sulfidic mine waste impoundments. A program was designed whereby an impoundment that contained sulfidic waste was studied to characterize pore water in the impoundment and to determine the fate of metals as they were transported downgradient. From this information a method to control dissolved metal transport was identified.
An appropriate field site where a sulfidic tailings impoundment was releasing heavy metals into an unconsolidated aquifer was identified and characterized over a 2.5 year period. Twenty-four piezometers and two lysimeters were installed upgradient from, within, and downgradient from the impoundment. Water samples were analyzed for 12 dissolved constituents, and field measurements for pH, redox potential, dissolved oxygen, temperature, alkalinity, and conductivity were made. Dissolution probably results from oxidation of sulfide minerals in the unsaturated tailings; infiltration transports the oxidation products downward through the saturated tailings into the underlying aquifer. Beneath the impoundment, the acidic water is partially neutralized by calcareous strata; pH-sensitive species precipitate as do some oxidized species. Continuing attenuation downgradient from the impoundment correlates mostly to precipitation of and sorption by oxidized mineral species.
A Case Study on the Aerobic and Anaerobic Removal of Manganese by Wetland Processes
Authors: Clayton L.A. , Bolis J.L. , Wildeman T.R. , Updegraff D.M. 
Published: February 2020

Abstract
Constructed wetlands have been utilized to passively remove metals and raise the pH of acid mine drainage. Manganese is typically the most difficult metal to remove from solution due to the high pH (&gt;8) required to form insoluble manganese precipitates. A study of the removal of manganese by wetland processes was conducted using two guidelines. A microbial ecosystem approach was used to select and test reasonable candidates for passive treatment. Also, a staged design approach consisting of laboratory and bench-scale studies was conducted to examine manganese removal by aerobic versus anaerobic constructed wetland processes. Aerobic laboratory experiments found that common green algae (pond scum) removed large concentrations of manganese from solution and raised the pH through photosynthesis. Aerobic bench-scale reservoirs were constructed containing green algae (predominantly Cladophora) and mine drainage that had passed through an anaerobic constructed wetland, but still contained 32 mg/1 Mn. Static and flow tests were conducted so that manganese was consistently removed to NPDES standards (2 mg/l). Manganese (oxide) coatings on the Cladophora appear to be an important removal mechanism. Four anaerobic bench-scale reactors were constructed, however, only the reactors containing a composted manure substrate achieved manganese removal to the NPDES standard for a significant portion of the experiment. In conclusion, manganese removal from severe acid mine drainage through the use of constructed wetlands requires a two-stage process. An aerobic algal pond appears to be a promising treatment method.