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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,783 records · Page 99
All sourcesNASA NTRSDOE OSTI
NASA NTRS1998

Paleosols and the evolution of atmospheric oxygen: a critical review

A number of investigators have used chemical profiles of paleosols to reconstruct the evolution of atmospheric oxygen levels during the course of Earth history (Holland, 1984, 1994; Kirkham and Roscoe, 1993; Ohmoto, 1996). Over the past decade Holland and his co-workers have examined reported paleosols from six localities that formed between 2.75 and 0.45 Ga. They have found that the chemical profiles of these paleosols are consistent with a dramatic change in atmospheric PO2 between 2.2 and 2.0 Ga from < or = 0.002 to > or = 0.03 atm (Holland, 1994). Ohmoto (1996) examined chemical data from twelve reported paleosols ranging in age from 2.9 to 1.8 Ga. He concluded that these chemical profiles indicate that atmospheric PO2 has not changed significantly during the past 3.0 Ga. We seek to resolve the conflict between these reconstructions through a broader examination of the paleosol literature, both to determine which reported paleosols can be definitively identified as such and to determine what these definite paleosols tell us about atmospheric evolution. We here review reports describing over 50 proposed paleosols, all but two are older than 1.7 Ga. Our review indicates that 15 of these reported paleosols can be definitively identified as ancient soils. The behavior of iron uring the formation of these 15 paleosols provides both qualitative and semiquantitative information about the evolution of the redox state of the atmosphere. Every definitely identified pre-2.44 Ga paleosol suffered significant Fe loss during weathering. This loss indicates that atmospheric PO2 was always less than about 5 x l0(-4) atm prior to 2.44 Ga. Analysis of the Hokkalampi paleosol (2.44-2.2 Ga) (Marmo, 1992) and the Ville Marie paleosol (2.38-2.215 Ga) (Rainbird, Nesbitt, and Donaldson, 1990) yield ambiguous results regarding atmospheric PO2. Loss of Fe during the weathering of the 2.245 to 2.203 Ga Hekpoort paleosol (Button, 1979) indicates that atmospheric PO2 was less than 8 x 10(-4) atm shortly before 2.2 Ga. The presence of red beds immediately overlying the Hokkalampi, Ville Marie, and Hekpoort paleosols suggests that by about 2.2 Ga there was an unquantified but substantial amount of oxygen in the atmosphere. Iron loss was negligible during formation of the 2.2 to 2.0 Ga Wolhaarkop (Holland and Beukes, 1990) and Drakenstein (Wiggering and Beukes, 1990) paleosols and during formation of all the later paleosols we previewed. Thus, atmospheric PO2 probably has been > or = 0.03 atm since sometime between 2.2 and 2.0 Ga.

Review, Academic↗
NASA NTRS2004

In situ x-ray and neutron powder diffraction study of LaNi5-xSnx-H systems

This paper will present results of in situ XRD measurements of LaNi4.75Sn0.25 .during the initial absorption-desorption cycle, These measurements were performed under a similar condition to that for LaNi4.75Al0.25 previously reported [1]. The data were analyzed by the Rietveld method. Lattice parameter change and strain formation accompanying hydride phase formation and decomposition will be discussed. In addition, results of in situ neutron diffraction of LaNi4.78Sn0.22, focusing on hydrogen occupation in the hydride phase, will be presented.

metal hydrides↗
NASA NTRS2008

Creating User-Friendly Tools for Data Analysis and Visualization in K-12 Classrooms: A Fortran Dinosaur Meets Generation Y

During the summer of 2007, as part of the second year of a NASA-funded project in partnership with Christopher Newport University called SPHERE (Students as Professionals Helping Educators Research the Earth), a group of undergraduate students spent 8 weeks in a research internship at or near NASA Langley Research Center. Three students from this group formed the Clouds group along with a NASA mentor (Chambers), and the brief addition of a local high school student fulfilling a mentorship requirement. The Clouds group was given the task of exploring and analyzing ground-based cloud observations obtained by K-12 students as part of the Students' Cloud Observations On-Line (S'COOL) Project, and the corresponding satellite data. This project began in 1997. The primary analysis tools developed for it were in FORTRAN, a computer language none of the students were familiar with. While they persevered through computer challenges and picky syntax, it eventually became obvious that this was not the most fruitful approach for a project aimed at motivating K-12 students to do their own data analysis. Thus, about halfway through the summer the group shifted its focus to more modern data analysis and visualization tools, namely spreadsheets and Google(tm) Earth. The result of their efforts, so far, is two different Excel spreadsheets and a Google(tm) Earth file. The spreadsheets are set up to allow participating classrooms to paste in a particular dataset of interest, using the standard S'COOL format, and easily perform a variety of analyses and comparisons of the ground cloud observation reports and their correspondence with the satellite data. This includes summarizing cloud occurrence and cloud cover statistics, and comparing cloud cover measurements from the two points of view. A visual classification tool is also provided to compare the cloud levels reported from the two viewpoints. This provides a statistical counterpart to the existing S'COOL data visualization tool, which is used for individual ground-to-satellite correspondences. The Google(tm) Earth file contains a set of placemarks and ground overlays to show participating students the area around their school that the satellite is measuring. This approach will be automated and made interactive by the S'COOL database expert and will also be used to help refine the latitude/longitude location of the participating schools. Once complete, these new data analysis tools will be posted on the S'COOL website for use by the project participants in schools around the US and the world.

Chambers, L. H.↗
NASA NTRS2002

Bubble Detachment in Variable Gravity Under the Influence of a Non-Uniform Electric Field

The objective of the study reported in this paper is to investigate the effects of variable, reduced gravity on the formation and detachment behavior of individual air bubbles under the influence of a non-uniform electric field. For this purpose, variable gravity experiments were carried out in parabolic nights. The non-uniform electric field was generated by a spherical electrode and a plate electrode. The effect of the magnitude of the non-uniform electric field and gravity level on bubble formation, development and detachment at an orifice was investigated. An image processing code was developed that allows the measurement of bubble volume, dimensions and contact angle at detachment. The results of this research can be used to explore the possibility of enhancing boiling heat transfer in the variable and low gravity environments by substituting the buoyancy force with a force induced by the electric field. The results of experiments and measurements indicate that the level of gravity significantly affects bubble shape, size and frequency. The electric field magnitude also influences bubble detachment, however, its impact is not as profound as that of variable gravity for the range of electric field magnitudes investigated in the present study.

Chang, Shinan↗
NASA NTRS2014

Spaceflight Microbiology: Benefits for Long Duration Spaceflight and Our Understanding of Microorganisms on Earth

Spaceflight microbiology is composed of both operational and experimental components that complement each other in our understanding of microbial interactions and their responses in the microgravity of spaceflight. Operationally, efforts to mitigate microbiological risk to the crew and the spacecraft have historically focused on minimizing the number of detectable organisms, relying heavily on preventative measures, including appropriate vehicle design, crew quarantine prior to flight, and stringent microbial monitoring. Preflight monitoring targets have included the astronauts, spaceflight foods, potable water systems, the vehicle air and surfaces, and the cargo carried aboard the spacecraft. This approach has been very successful for earlier missions; however, the construction and long-term habitation of the International Space Station (ISS) has created the need for additional inflight monitoring of the environment and potable water systems using hardware designed for both in-flight microbial enumeration and sample collection and return to Earth. In addition to operational activities, the ISS is providing a research platform to advance our understanding of microbiomes in the built environment. Adding to the research possibilities of this system are multiple reports of unique changes in microbial gene expression and phenotypic responses, including virulence and biofilm formation, in response to spaceflight culture. The tremendous potential of the ISS research platform led the National Research Council to recommend that NASA utilize the ISS as a microbial observatory. Collectively, the findings from operational and research activities on the ISS are expected to both enable future space exploration and translate to basic and applied research on Earth.

Ott, C. Mark↗
DOE OSTI2022

In situ analysis of the nucleation of O- and Zn-polar ZnO nanowires using synchrotron-based X-ray diffraction

The selection of the polarity of ZnO nanowires grown by chemical bath deposition offers a great advantage for their integration into a wide variety of engineering devices. However, the nucleation process of ZnO nanowires and its dependence on their polarity is still unknown despite its importance for optimizing their morphology and properties and thus to enhance the related device performances. To tackle this major issue, we combine an in situ analysis of the nucleation process of O- and Zn-polar ZnO nanowires on O- and Zn-polar ZnO single crystals, respectively, using synchrotron radiation-based grazing incidence X-ray diffraction with ex situ transmission and scanning electron microscopy. We show that the formation of ZnO nanowires obeys three successive phases from the induction, through nucleation to growth phases. Additionally, the characteristics of each phase, including the nucleation temperature, the shape and dimension of nuclei, as well as their radial and axial development are found to depend on the polarity of ZnO nanowires. A comprehensive description reporting the dominant physicochemical processes in each phase and their dependence on the polarity of ZnO nanowires is presented, revisiting their formation process step-by-step. These findings provide a deeper understanding of the phenomena at work during the growth of ZnO nanowires by chemical bath deposition and open the perspective to develop a more accurate control of their properties at each step of the formation process.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2021

Texture Formation in Polycrystalline Thin Films of All‐Inorganic Lead Halide Perovskite

Abstract Controlling grain orientations within polycrystalline all‐inorganic halide perovskite solar cells can help increase conversion efficiencies toward their thermodynamic limits; however, the forces governing texture formation are ambiguous. Using synchrotron X‐ray diffraction, mesostructure formation within polycrystalline CsPbI 2.85 Br 0.15 powders as they cool from a high‐temperature cubic perovskite (α‐phase) is reported. Tetragonal distortions (β‐phase) trigger preferential crystallographic alignment within polycrystalline ensembles, a feature that is suggested here to be coordinated across multiple neighboring grains via interfacial forces that select for certain lattice distortions over others. External anisotropy is then imposed on polycrystalline thin films of orthorhombic (γ‐phase) CsPbI 3‐ x Br x perovskite via substrate clamping, revealing two fundamental uniaxial texture formations; i) I‐rich films possess orthorhombic‐like texture (<100> out‐of‐plane; <010> and <001> in‐plane), while ii) Br‐rich films form tetragonal‐like texture (<110> out‐of‐plane; <110> and <001> in‐plane). In contrast to relatively uninfluential factors like the choice of substrate, film thickness, and annealing temperature, Br incorporation modifies the γ‐CsPbI 3− x Br x crystal structure by reducing the orthorhombic lattice distortion (making it more tetragonal‐like) and governs the formation of the different, energetically favored textures within polycrystalline thin films.

Steele, Julian A.↗
DOE OSTI2024

The Curious Case of [AnH(NR 2 ) 3 ] (An = Th, U; R = SiMe 3 ): Two Monomeric Actinide Hydrides Revisited

The reaction of AnCl 4 (DME) x (An = Th, x = 2; An = U, x = 0) with 4 equiv of NaNR 2 (R = SiMe 3 ) in THF at 65 °C results in the formation of [An{N(R)(SiMe 2 CH 2 )}(NR 2 ) 2 ] (An = U, 1; An = Th, 2), and not the reported monomeric actinide hydrides, [AnH(NR 2 ) 3 ], as expected. Furthermore, both complexes 1 and 2 were characterized by X-ray crystallography. Surprisingly, their unit cell parameters are remarkably close to those reported for [AnH(NR 2 ) 3 ], suggesting that the original crystals of [AnH(NR 2 ) 3 ] were, in fact, [An{N(R)(SiMe 2 CH 2 )}(NR 2 ) 2 ], but were misidentified. Reduction of 1 with 1.1 equiv of KC 8 in THF, in the presence of 1 equiv of 2.2.2-cryptand, results in the formation of [K(2.2.2-cryptand)][U{N(R)(SiMe 2 CH 2 )}(NR 2 ) 2 ] (3) in good yield. Likewise, the reaction of 1 with 1 equiv of bis(diisopropylamino)cyclopropenylidene (BAC) results in the formation of the BAC adduct, [(BAC)U{N(R)(SiMe 2 CH 2 )}(NR 2 ) 2 ] (4), in moderate yield. Finally, the addition of H 2 (10 bar) to 2 in C 6 D 6 at room temperature results in the formation of the targeted monomeric hydride, [ThH(NR 2 ) 3 ], in 32% yield, according to integrations against an internal standard. However, removal of the H 2 atmosphere results in rapid reformation of 2. In contrast, the addition of H 2 (10 bar) to 1 in C 6 D 6 at room temperature results in no apparent reaction.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

Direct observation of diamond formation in a shock-compressed high explosive

Understanding the formation timescale and structure of carbonaceous reaction products is critical for modeling the high-pressure equation-of-state of organic materials. We use the National Ignition Facility to shock-compress polycrystalline TATB (C 6 H 6 N 6 O 6 ) samples to ~70–130 GPa and ~4000–5500 K, employing in situ nanosecond X-ray diffraction to probe reaction products and velocimetry to measure transmitted compression wave profiles. Our diffraction data is consistent with the formation of diamond over timescales less than ~60 ns. This represents carbon condensation from a molecular explosive on timescales three times faster than previously reported and the earliest observation of diamond produced from reacting TATB. Reactive flow simulations with explicit chemistry reproduce the observed temporal structure within wave profiles to inform the distribution of P-T states. These findings provide direct evidence of ultrafast diamond formation in a reactive system at extreme conditions and provide new constraints for models of shock and detonation chemistry.

Clarke, Samantha M. [Lawrence Livermore National L↗
NASA NTRS2005

Analysis of Rapidly Developing Low Cloud Ceilings in a Stable Environment

This report describes the work done by the Applied Meteorology Unit (AMU) in developing a database of days that experienced rapid (< 90 minutes) low cloud formation in a stable atmosphere, resulting in ceilings at the Shuttle Landing Facility (TTS) that violated Space Shuttle Flight Rules (FR). The meteorological conditions favoring the rapid formation of low ceilings include the presence of any inversion below 8000 ft, high relative humidity beneath the inversion, and a clockwise turning of the winds from the surface to the middle troposphere (approx. 15000 ft). The AMU compared and contrasted the atmospheric and thermodynamic conditions between days with rapid low ceiling formation and days with low ceiling resulting from other mechanism. The AMU found that the vertical wind profile is the probable discerning factor between the rapidly-forming ceiling days and other low ceiling days at TTS. Most rapidly-developing low ceiling days had a clockwise turning of the winds with height, whereas other low ceiling days typically had a counter-clockwise turning of the winds with height or negligible vertical wind shear. Forecasters at the Space Meteorology Group (SMG) issue 30 to 90 minute forecasts for low cloud ceilings at TTS to support Space Shuttle landings. Mission verification statistics have shown ceilings to be the number one forecast challenge. More specifically, forecasters at SMG are concerned with any rapidly developing clouds ceilings below 8000 ft in a stable, capped thermodynamic environment, Therefore, the AMU was tasked to examine archived events of rapid stable cloud formation resulting in ceilings below 8000 ft, and document the atmospheric regimes favoring this type of cloud development. The AMU examined the cool season months of November to March during the years of 1993-2003 for days that had low-level inversions and rapid, stable low cloud formation that resulted in ceilings violating the Space Shuttle FR. The AMU wrote and modified existing code to identify inversions from the morning Cape Canaveral, FL rawinsonde (XMR) during the cool season and output pertinent sounding information. They parsed all days with cloud ceilings below 8000 ft at TTS, forming a database of possible rapidly-developing low ceiling events. Days with precipitation or noticeable fog bum-off situations were excluded from the database. Only the daytime hours were examined for possible ceiling development events since low clouds are easier to diagnose with visible satellite imagery. Follow-on work would expand the database to include nighttime cases, using a special enhancement of the infrared imagery for identifying areas of low clouds. The report presents two sample cases of rapidly-developing low cloud ceilings. These cases depict the representative meteorological and thermodynamic characteristics of such events. The cases also illustrate how quickly the cloud decks can develop, sometimes forming in 30 minutes or less. The report also summarizes the composite meteorological conditions for 20 event days with rapid low cloud ceiling formation and 48 non-events days consisting of advection or widespread low cloud ceilings. The meteorological conditions were quite similar for both the event and non-event days, since both types of days experienced low cloud ceilings. Both types of days had a relatively moist environment beneath the inversion based below 8000 ft. In the 20 events identified, de onset of low ceilings occurred between 1200-1800 UTC in every instance. The distinguishing factor between the event and non-event days appears to be the vertical wind profile in the XMR sounding. Eighty-five percent of the event days had a clockwise turning of the winds with height in the lower to middle troposphere whereas 83% of the non-events had a counter-clockwise turning of the winds with height or negligible vertical wind shear. A clockwise turning of the winds with height indicates a warm advection regime, which supports large-scale rising motn and possible cloud formation. Meanwhile, a counter-clockwise turning of the winds with height indicates cold advection or sinking motion in a post-cold frontal environment.

Wheeler, Mark M.↗
NASA NTRS1994

Effective declutter of complex flight displays using stereoptic 3-D cueing

The application of stereo technology to new, integrated pictorial display formats has been effective in situational awareness enhancements, and stereo has been postulated to be effective for the declutter of complex informational displays. This paper reports a full-factorial workstation experiment performed to verify the potential benefits of stereo cueing for the declutter function in a simulated tracking task. The experimental symbology was designed similar to that of a conventional flight director, although the format was an intentionally confused presentation that resulted in a very cluttered dynamic display. The subject's task was to use a hand controller to keep a tracking symbol, an 'X', on top of a target symbol, another X, which was being randomly driven. In the basic tracking task, both the target symbol and the tracking symbol were presented as red X's. The presence of color coding was used to provide some declutter, thus making the task more reasonable to perform. For this condition, the target symbol was coded red, and the tracking symbol was coded blue. Noise conditions, or additional clutter, were provided by the inclusion of randomly moving, differently colored X symbols. Stereo depth, which was hypothesized to declutter the display, was utilized by placing any noise in a plane in front of the display monitor, the tracking symbol at screen depth, and the target symbol behind the screen. The results from analyzing the performances of eight subjects revealed that the stereo presentation effectively offsets the cluttering effects of both the noise and the absence of color coding. The potential of stereo cueing to declutter complex informational displays has therefore been verified; this ability to declutter is an additional benefit from the application of stereoptic cueing to pictorial flight displays.

Parrish, Russell V.↗
DOE OSTI2021

Correction to “Critical Assessment of the Thermodynamics of Vacancy Formation in Fe 2 O 3 Using Hybrid Density Functional Theory”

After publication, the authors discovered two errors in the DFT data reported which partially affect Figures 2, 7, and 8. Additionally, while these errors do not affect the main findings of this work, we wish to make sure these issues do not complicate future comparisons and so we have added this correction for publication.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Large-Volume Stimulation of Rock for Greatly Enhanced Fluids Recovery using Targeted Seismic-Assisted Hydraulic Fracturing (Final Technical Report)

This project has developed and demonstrated a new technology for large-volume and targeted comminution of rock in low permeability formations to enhance recovery from unconventional oil and gas (UOG) resources. The technology is based on a strategically designed interaction of multiple induced seismic pulses that assist the hydraulic fracturing process to enhance shear and multi-planar crack formation. This greatly increased rock stimulation, through bulk comminution, is expected to cause significant increase in permeability leading to enhancement of recovery factors for sub- surface fluids. The proposed technology is especially applicable for enhanced recovery in emerging UOG plays, such as ductile shales that are resistant to opening-mode fracturing by conventional hydraulic fracturing processes. The project combines an integrated experimental and computation approach to develop and demonstrate a modular technology that can be easily implement in the field to augment current practices. The effort integrates a fundamental scientific understanding of dynamic material response under constraint and damage-induced permeability and porosity enhancements at multiple length scales, along with models of comminution due to the local release of kinetic energy associated with high shear strain rate of dynamic deformation. The results will be validated through small-scale experiments and then implemented in a lab-scale field test to demonstrate the developed technology. The project involves collaboration between a solid mechanician, a materials scientist, and a petroleum engineering geo-mechanician. It builds on a successful history of success and collaboration that includes both fundamental scientific exploration and technology development.

04 OIL SHALES AND TAR SANDS↗
DOE OSTI2026

Mixed Precursor and Future Climate in the Southeast U.S. Field Campaign Report

The generation of atmospheric aerosols is a fundamental process in aerosol-climate interactions, where particles act as nuclei for cloud formation and ultimately influence Earth’s radiative balance. Understanding aerosol precursors, chemical compositions, and formation mechanisms, particularly for secondary organic aerosols (SOAs), is essential for assessing their overall impact on climate. Aerosol-climate interactions are especially important in the Southeastern United States (SE-US), where the atmosphere is strongly influenced by both biogenic and anthropogenic emissions, as well as intense land-atmosphere convective coupling. Current mechanistic representations of SOA formation under ambient conditions are largely extrapolated from laboratory-scale oxidation experiments involving individual volatile organic compounds (VOCs), which are often assumed to behave independently when present in mixtures. However, recent empirical evidence demonstrates that coexisting VOC precursors can undergo previously unexplored molecular-scale interactions that significantly alter SOA physicochemical properties, including mass loading, yield, and water uptake.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1982

Cell and module formation research area

Metallization is discussed. The influence of hydrogen on the firing of base-metal pastes in reducing atmospheres is reported. A method for optimization of metallization patterns is presented. A process sequence involving an AR coating and thick-film metallization system capable of penetrating the AR coating during firing is reported. Design and construction of the NMA implantation machine is reported. Implanted back-surface fields and NMA primary (front) junctions are discussed. The use of glass beads, a wave-soldering device, and ion milling is reported. Processing through the module fabrication and environmental testing of its design are reported. Metallization patterns by mathematical optimization are assessed.

Bickler, D. B.↗
NASA NTRS1981

Formation of pyrophosphate, tripolyphosphate, and phosphorylimidazole with the thioester, N, S-diacetylcysteamine, as the condensing agent

The formation of pyrophosphate, tripolyphosphate and phosphorylimidazole from orthophosphate in the presence of the thioester N, S-diacetylcysteamine is reported. Reactions performed with 0.20 M orthophosphate and 0.20 M N, S-diacetylcysteamine in 0.40 M imidazole under drying conditions at 50 C yielded pyrophosphate and tripolyphosphate after six days in the presence and absence of divalent metal ions. Reactions carried out at ambient temperature yielded phosphorylimidazole in the presence or absence of 0.05 M MgCl2, phosphorylimidazole and pyrophosphate in the presence of 0.05 M CaCl2, and pyrophosphate and tripolyphosphate in the presence of 0.15 M CaCl2. Such reactions represent potential pathways for the formation of energy-rich compounds providing free energy for use in prebiotic biopolymer synthesis.

Weber, A. L.↗
NASA NTRS1998

Development of High Conductivity Lithium-Ion Electrolytes for Low Temperature Cell Applications

NASA has continued interest in developing power sources which are capable of operating at low temperatures (-20 C and below) to enable future missions, such as the Mars Rover and Lander. Thus, under a program sponsored by the Mars Exploration Program, we have been involved in developing Li-ion batteries with improved low temperature performance. To accomplish this task, the focus of the research has been upon the development of advanced electrolyte systems with improved low temperature properties. This had led to the identification of a carbonate-based electrolyte, consisting of 1.0 M LiPF6 in EC + DEC + DMC (33:33:34), which has been shown to have excellent performance at -20 C in Li-ion AA-size prototype cells. Other groups are also actively engaged in developing electrolytes which can result in improved low temperature performance of Li-ion cells, including Polystor, Yardney, and Covalent. In addition to developing cells capable of operation at -20 C, there is continued interest in systems which can successfully operate at even lower temperatures (less than -30 C) and at high discharge rates (greater than C/2). Thus, we are currently focusing upon developing advanced electrolytes which are highly conductive at low temperatures and will result in cells capable of operation at -40 C. One approach to improve the low temperature conductivity of ethylene carbonate-based electrolytes involves adding co-solvents which will decrease the viscosity and extend the liquid range. Candidate solvent additives include formates, acetates, cyclic and aliphatic ethers, lactones, as well as other carbonates. Using this approach, we have prepared a number of electrolytes which contain methyl formate (MF), methyl acetate (MA), ethyl acetate (EA), ethyl proprionate (EP), and 1,2-dimethoxyethane (DME), some of which have been characterized and reported. Other groups have also reported electrolytes based on mixtures of carbonates and acetates. In the present study, electrolytes which have been identified to have good low temperature conductivity and stability were incorporated into lithium-graphite cells for evaluation. Using various electrochemical methods, including ac impedence and DC micropolarization techniques, the film formation characteristics of graphite electrodes in contact with various lectrolyte formulations was investigated.

Smart, M. C.↗