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DOE OSTI2026

Solid neon as a noise-resilient host for electron qubits above 100 mK

Solid neon can be used as a solid host for single-electron qubits. At temperatures of around 10 mK, electron-on-solid-neon charge qubits exhibit long coherence times and high operation fidelities. However, a systematic characterization of the noise features of such systems is needed for the development of scalable quantum information architectures. Here, in this work, we show that solid neon can be used as a noise-resilient host for electron qubits above 100 mK. We examine the resilience of solid neon against charge and thermal noise when electron-on-solid-neon charge qubits are operated away from the charge-insensitive sweet spot and at elevated temperatures. We show that the extracted high-frequency charge noise density of electron-on-solid-neon qubits, projected as voltage fluctuations on nearby electrodes, is between 10 −4 μV 2 Hz −1 and 10 −6 μV 2 Hz −1 at 0.01 MHz to 1 MHz, which is comparable to common semiconductor hosts. We also show that the electron-on-solid-neon charge qubits operating at frequencies of around 5 GHz can maintain echo coherence times of over 1 μs at temperatures up to 400 mK.

42 ENGINEERING↗

DOE OSTI2022

Declining carbohydrate solubilization with increasing solids loading during fermentation of cellulosic feedstocks by Clostridium thermocellum: documentation and diagnostic tests

Abstract Background For economically viable 2nd generation biofuels, processing of high solid lignocellulosic substrate concentrations is a necessity. The cellulolytic thermophilic anaerobe Clostridium thermocellum is one of the most effective biocatalysts for solubilization of carbohydrate harbored in lignocellulose. This study aims to document the solubilization performance of Clostridium thermocellum at increasing solids concentrations for two lignocellulosic feedstocks, corn stover and switchgrass, and explore potential effectors of solubilization performance. Results Monocultures of Clostridium thermocellum demonstrated high levels of carbohydrate solubilization for both unpretreated corn stover and switchgrass. However, fractional carbohydrate solubilization decreases with increasing solid loadings. Fermentation of model insoluble substrate (cellulose) in the presence of high solids lignocellulosic spent broth is temporarily affected but not model soluble substrate (cellobiose) fermentations. Mid-fermentation addition of cells ( C. thermocellum ) or model substrates did not significantly enhance overall corn stover solubilization loaded at 80 g/L, however cultures utilized the model substrates in the presence of high concentrations of corn stover. An increase in corn stover solubilization was observed when water was added, effectively diluting the solids concentration mid-fermentation. Introduction of a hemicellulose-utilizing coculture partner, Thermoanaerobacterium thermosaccharolyticum, increased the fractional carbohydrate solubilization at both high and low solid loadings. Residual solubilized carbohydrates diminished significantly in the presence of T. thermosaccharolyticum compared to monocultures of C. thermocellum, yet a small fraction of solubilized oligosaccharides of both C 5 and C 6 sugars remained unutilized. Conclusion Diminishing fractional carbohydrate solubilization with increasing substrate loading was observed for C. thermocellum -mediated solubilization and fermentation of unpretreated lignocellulose feedstocks. Results of experiments involving spent broth addition do not support a major role for inhibitors present in the liquid phase. Mid-fermentation addition experiments confirm that C. thermocellum and its enzymes remain capable of converting model substrates during the middle of high solids lignocellulose fermentation. An increase in fractional carbohydrate solubilization was made possible by (1) mid-fermentation solid loading dilutions and (2) coculturing C. thermocellum with T. thermosaccharolyticum , which ferments solubilized hemicellulose. Incomplete utilization of solubilized carbohydrates suggests that a small fraction of the carbohydrates is unaffected by the extracellular carbohydrate-active enzymes present in the culture.

09 BIOMASS FUELS↗

DOE OSTI2024

In Situ Characterization of Interface Evolution in Argyrodite‐Based All‐Solid‐State Li Batteries

Interfacial stability is one of the critical challenges in all-solid-state Li metal batteries. Multiple processes such as solid electrolyte (SE) decomposition and lithium dendrite growth take place at the solid interfaces during cycling, leading to the overall cell failure. To deconvolute these complex processes, in situ characterization is of paramount importance to elucidate the interfacial evolution on the SE upon Li plating/stripping. Herein, an all-solid-state asymmetric in situ cell is developed that allows the direct visualization of the highly localized Li plating/stripping processes under the optical microscope. Moreover, this cell configuration enables reliable post-mortem chemical and morphological analysis of the intact SE/Li interface. Using combined scanning electron microscopy and energy-dispersive X-ray spectroscopy, the study reveals that the evolution of the Li argyrodite interface is strongly influenced by the current density, particularly in terms of chemical distribution and Li plating morphology. More specifically, the solid interface is LiCl-rich with the formation of Li cubes at low current densities, while high currents result in more uniform elemental distribution and filament morphology. These findings elucidate the dynamic evolution mechanism at solid interfaces and offer valuable guidance for developing stable solid interfaces in all-solid-state Li metal batteries.

Huang, Di↗

DOE OSTI2019

The evaluation of critical rare earth element (REE) enriched treatment solids from coal mine drainage passive treatment systems

Rare earth elements (REE; lanthanides and Y) are essential for the development of clean energy technologies. Global demand for REE is expected to increase sharply in the coming decades, especially for certain energy-critical REE (e.g., Y and Nd), spurring investigations into novel sources of REEs. Polluted mine drainage from eastern U.S. coalfields contains elevated concentrations of dissolved Fe, Al, and Mn and is also enriched in REE by up to three orders of magnitude over unpolluted groundwater. Mine drainage remediation systems, designed to precipitate dissolved metals, can sequester >90% of dissolved REE into the precipitated solids (treatment solids). These solids, landfilled at cost to treatment system operators, are a promising REE source. Passive treatment systems with diverse geochemical environments were sampled to determine REE mobility in these systems and REE concentrations in treatment solids. Passive treatment systems were found to produce middle and heavy REE-enriched solids, relative to the North American Shale Composite, with up to 1950 ppm REE and 55% energy-critical REE. SEM-EDS and synchrotron μ-XRF analysis demonstrate the association of REE with Mn-oxide coatings on limestone from a passive treatment system. Calculated concentration factors indicate that passive treatment systems using natural processes (e.g., drainable limestone beds and vertical flow ponds) concentrate REE into treatment solids approximately three times more effectively compared to active treatment systems using caustic chemical additions (e.g., lime). This study suggests that passive treatment systems effectively concentrate REE into treatment solids and these solids could be an alternative and more environmentally friendly source of REE compared to conventional mining on land or the seafloor. Results of this study can also aid in the design of treatment systems engineered to remove and concentrate critical REE which could provide a financial incentive to treat polluted mine water.

58 GEOSCIENCES↗

DOE OSTI2017

Compatibility issues between electrodes and electrolytes in solid-state batteries

Remarkable success has been achieved in the discovery of ceramic alkali superionic conductors as electrolytes in solid-state batteries; however, obtaining a stable interface between these electrolytes and electrodes is difficult. Only limited studies on the compatibility between electrodes and solid electrolytes have been reported, partially because of the need for expensive instrumentation and special cell designs. Without simple yet powerful tools, these compatibility issues cannot be systematically investigated, thus hindering the generalization of design rules for the integration of solid-state battery components. Herein, we present a methodology that combines density functional theory calculations and simple experimental techniques such as X-ray diffraction, simultaneous differential scanning calorimetry and thermal gravimetric analysis, and electrochemistry to efficiently screen the compatibility of numerous electrode/electrolyte pairs. We systemically distinguish between the electrochemical stability of the solid-state conductor, which is relevant wherever the electrolyte contacts an electron pathway, and the electrochemical stability of the electrode/electrolyte interfaces. For the solid electrolyte, we are able to computationally derive an absolute thermodynamic stability voltage window, which is small for Na 3 PS 4 and Na 3 PSe 4 , and a larger voltage window which can be kinetically stabilized. The experimental stability, when measured with reliable techniques, falls between these thermodynamic and kinetic limits. Employing a Na solid-state system as an example, we demonstrate the efficiency of our method by finding the most stable system (NaCrO 2 |Na 3 PS 4 |Na–Sn) within a selected chemical space (more than 20 different combinations of electrodes and electrolytes). Important selection criteria for the cathode, electrolyte, and anode in solid-state batteries are also derived from this study. The current method not only provides an essential guide for integrating all-solid-state battery components but can also significantly accelerate the expansion of the electrolyte/electrode compatibility data.

25 ENERGY STORAGE↗

DOE OSTI2025

Measuring the buried interphase between solid electrolytes and lithium metal using neutrons

Interfaces are the key to next-generation high-energy batteries including solid-state Li metal batteries. In solid-state batteries, the buried nature of solid–solid electrolyte–electrode interfaces makes studying them difficult. Neutrons have significant potential to non-destructively probe these buried solid–solid interfaces. This work presents a comparative study using both neutron depth profiling (NDP) and neutron reflectometry (NR) to study a model lithium metal–lithium phosphorus oxynitride (LiPON) solid electrolyte system. In the NDP data, no distinct interphase is observed at the interface. NR shows a difference between electrodeposited, and vapor deposited LiPON–Li interfaces but finds both are gradient interphases that are less than 30 nm thick. Additional simulations of the LiPON–Li 2 O–Li system demonstrate that NDP has an excellent resolution in the 50 nm–1 μm regime while NR has an ideal resolution from 0.1–200 nm with different sample requirements. Together NDP and NR can provide a complementary understanding of interfaces between Li metal and solid electrolytes across relevant length scales.

Westover, Andrew S. [Oak Ridge National Laboratory↗

DOE OSTI2024

Optimal spectral resolution for solids and liquids using FT and other infrared spectrometers: How much resolution do you really need?

In this study we investigate the possibility of using spectral resolutions for infrared measurements of solids and liquids that are not powers of two, e.g. are not at 1, 2, 4, 8, or 16 cm-1 resolution. In almost all reported literature of the last fifty years the resolution used to record for a Fourier transform infrared spectrum has been a power of two. This stems from the fact that 1) the Cooley-Tukey algorithm used to compute such a transform was constructed to use only powers of two and was also driven by 2) the fact that the computing horsepower required to compute the Fourier transform increases as N?log?_2 (N), where N is the number of points in the interferogram (spectrum). For typical spectra, however, the CPU time is no longer a consideration. Our study is based on both liquid and solid spectra, all of which were recorded at 2 cm-1 resolution. There were at total of 70 solids spectra representing 2,472 spectral peaks and 61 liquids spectra (1,765 spectral peaks), each peak being inspected for being singlet / multiplet in nature. Of the 1,765 liquid bands examined, only 27 had widths less than 5 cm-1. Of the 2,472 solid bands examined, only 39 peaks have widths less than 5 cm-1. For liquids, the mean peak width is 24.7 cm-1 but the median peak width is 13.7 cm-1, and, similarly, for solids, the mean peak width is 22.2 cm-1 but the median peak width is 11.2 cm-1. In both cases, solids and liquids, a skewed peak widths distribution was observed, the peak of the distribution representing narrower bands in the 7 to 9 cm-1 FWHM range but displaying a long tail to the very broad bands, with some displaying spectral widths of 100 cm-1 or more. Because one of the most important criteria for successful instrumental design in IR spectroscopy is the spectral resolution, the data were further analyzed showing that a value to resolve 95% of all bands is 5.7 cm-1 for liquids and 5.3 cm-1 for solids; such a resolution would capture the native linewidth (no instrumental broadening) of 95% of all the solids and liquid bands, respectively. Based on the present results we suggest that, when accounting only for intrinsic linewidths an optimized resolution of 6.0 cm-1 will capture 91% of all condensed-phase bands for IR detection of chemical, mineral, and biological materials.

Forland, Brenda M.↗

DOE OSTI2021

Method—Using Microelectrodes to Explore Solid Polymer Electrolytes

Solid polymer electrolytes are an emerging technology in electrochemistry driven by their use in energy applications such as fuel cells, electrolyzers, and solid-state batteries. Compared to traditional liquid electrolytes, solid polymer electrolytes provide safer, cheaper, and potentially improved device performance. However, there is a lack of standard experimental methods for studying solid electrolytes. Microelectrodes have inherent benefits capable of filling this experimental gap due primarily to their integration into model electrochemical cells with solid electrolytes that represent complex interfaces, enabling additional insight into reaction processes. In this tutorial review, we explore the use of microelectrodes to study solid polymer electrolytes, beginning with a brief history of the field including common experimental cell designs and their benefits and drawbacks. Methods of evaluating essential kinetic and mass-transport parameters are then examined. In addition, the key studies of the past 30 years utilizing microelectrode cells and solid polymer electrolytes are summarized, with important results highlighted and compared. Finally, future studies of solid polymer electrolytes with microelectrodes and potential new avenues of research are commented on.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2024

Optimal Spectral Resolution for Infrared Studies of Solids and Liquids

Due to a legacy originating in the limited capability of early computers, the spectroscopic resolution used in Fourier transform infrared spectroscopy and other systems has largely been implemented using only powers of two for more than 50 years. In this study, we investigate debunking the spectroscopic lore of, e.g., using only 2, 4, 8, or 16 cm −1 resolution and determine the optimal resolution in terms of both (i) a desired signal-to-noise ratio and (ii) efficient use of acquisition time. The study is facilitated by the availability of solids and liquids reference spectral data recorded at 2.0 cm −1 resolution and is based on an examination in the 4000–400 cm −1 range of 61 liquids and 70 solids spectra, with a total analysis of 4237 peaks, each of which was also examined for being singlet/multiplet in nature. Of the 1765 liquid bands examined, only 27 had widths <5 cm −1 . Of the 2472 solid bands examined, only 39 peaks have widths <5 cm −1 . For both the liquid and solid bands, a skewed distribution of peak widths was observed: For liquids, the mean peak width was 24.7 cm −1 but the median peak width was 13.7 cm −1 , and, similarly, for solids, the mean peak width was 22.2 cm −1 but the median peak width was 11.2 cm −1 . While recognizing other studies may differ in scope and limiting the analysis to only room temperature data, we have found that a resolution to resolve 95% of all bands is 5.7 cm −1 for liquids and 5.3 cm −1 for solids; such a resolution would capture the native linewidth (not accounting for instrumental broadening) for 95% of all the solids and liquid bands, respectively. After decades of measuring liquids and solids at 4, 8, or 16 cm −1 resolution, we suggest that, when accounting only for intrinsic linewidths, an optimized resolution of 6.0 cm −1 will capture 91% of all condensed-phase bands, i.e., broadening of only 9% of the narrowest of bands, but yielding a large gain in signal-to-noise with minimal loss of specificity.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2022

Comparison of All Solid Cancer Mortality and Incidence Dose-Response in the Life Span Study of Atomic Bomb Survivors, 1958–2009

Recent analysis of all solid cancer incidence (1958–2009) in the Life Span Study (LSS) revealed evidence of upward curvature in the radiation dose response among males but not females. Upward curvature in sex-averaged excess relative risk (ERR) for all solid cancer mortality (1950–2003) was also observed in the 0–2 Gy dose range. As reasons for non-linearity in the LSS are not completely understood, we conducted dose response analyses for all solid cancer mortality and incidence applying similar methods (1958–2009 follow-up, DS02R1 doses, including subjects notin-city (NIC) at the time of the bombing) and statistical models. Incident cancers were ascertained from Hiroshima and Nagasaki cancer registries, while cause of death was ascertained from death certificates over entire Japan. The study included 105,444 LSS subjects who were alive and not known to have cancer before Jan 1, 1958 (80,205 with dose estimates and 25,239 NIC subjects). Between 1958 and 2009, there were 3.1 million person-years (PY) and 22,538 solid cancers for incidence analysis and 3.8 million PY and 15,419 solid cancer deaths for mortality analysis. We fitted sex-specific ERR models adjusted for smoking to both types of data. Over the entire range of doses, solid cancer mortality dose response exhibited a borderline significant upward curvature among males (P=0.062) and significant upward curvature among females (P=0.010); for solid cancer incidence, as before, we found a significant upward curvature among males (P=0.001) but not among females (P=0.624). The sex difference in magnitude of dose response curvature was statistically significant for cancer incidence (P=0.017) but not for cancer mortality (P=0.781). The results of analyses in the 0–2 Gy range and restricted lower dose ranges generally supported inferences made about the sex-specific dose response shape over the entire range of doses for each outcome. Patterns of sex-specific curvature by calendar period (1958–1987 vs 1988–2009) and age at exposure (0–19 vs 20–83) varied between mortality and incidence data, particularly among females, although for each outcome there was an indication of curvature among 0–19 year old male survivors in both calendar periods and among 0–19 year old female survivors in the recent period. Collectively, our findings indicate that the upward curvature in all solid cancer dose response in the LSS is neither specific to males nor to incidence data; it appears to depend on composition of case series and age at exposure or time. Further follow-up and site-specific analyses of cancer mortality and incidence will be important to confirm the emerging trend in dose response curvature among young survivors and unveil the contributing factors and sites.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗

DOE OSTI2020

Composite Analysis Solid Waste Release Data Reduction of Activity Flux from Waste Sites to the Vadose Zone for Baseline Assessment

This environmental calculation file (ECF) describes the data reduction methodology for the solid waste release datasets generated by the Composite Analysis Solid Waste Release (CASWR) model (CP-62766, Model Package Report: Composite Analysis Solid Waste Release Model [CASWR Model]) and documents the resulting reduced datasets for the updated Composite Analysis (CA) baseline assessment. This ECF is in support of the updated Hanford Site CA. The purpose of the updated Hanford Site CA is to provide an estimate of the cumulative radiological impacts from active and planned low-level radioactive waste disposals and other potentially interacting radioactive waste disposal sources that will remain following Hanford Site closure. The vadose zone modeling activities associated with the CA includes solid waste forms as contaminant sources. To support the modeling of solid waste transport from the vadose zone to the groundwater at the Hanford Site, the CASWR model was designed to generate deterministic radionuclide release rates for the Hanford Site Central Plateau solid waste disposal sites. The complete CASWR model-generated dataset for the CA Baseline Assessment consists of 2,378,831 sets of time and release rates (1,073,869 sets for the 200 East Area and 1,304,962 sets for the 200 West Area), representing a course of the simulation from year 1953 to year 12,069, 16 radiological contaminants of potential concern (COPCs), and 237 solid waste sources as documented in ECFHANFORD- 19-0112, Solid Waste Release Calculations for the Composite Analysis Baseline Assessment. For several of the STOMP vadose zone models, the number of release rate data pairs required for release at all waste sites would exceed the limitations imposed by the STOMP modelling software package used to simulate contaminant transport through the vadose zone. As a result, a data reduction of the CASWR dataset is required prior to its use as a source input for the CA vadose zone modeling activities.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2020

Tank 49H Solids Disturbance Analysis

Tank 49H will serve as the feed tank for the Salt Waste Processing Facility (SWPF). Transfers into Tank 49H may disturb solids that have settled to the bottom of the tank, resulting in feed that may exceed the insoluble solids content limit of 1200 mg/L from the SWPF Waste Acceptance Criteria (WAC). During a transfer into Tank 49H, material that free falls from the Tank 49H B4 downcomer and passes through the supernate could potentially disturb the solids on the bottom of the tank and scour or suspend solids from a settled solids layer or turbid region. The scope of this task is to perform fluid flow analysis to determine the impact of a “plunging jet” through the B4 downcomer on solids in Tank 49H and to determine a minimum liquid level to be maintained in Tank 49H prior to transfers that will minimize disturbing the solids and exceeding the SWPF WAC limits for insoluble solids carryover to SWPF.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2022

Quantifying Antibiotic Distribution in Solid and Liquid Fractions of Manure Using a Two-Step, Multi-Residue Antibiotic Extraction

Antibiotic distribution and analysis within liquid and solid fractions of manure are highly variable due to each compound’s respective physiochemical properties. This study developed and evaluated a uniform method extracting 10 antibiotics from 4 antibiotic classes (tetracycline, sulfonamides, macrolides, and β-lactam) from unprocessed manure, solid–liquid separated manure, and composted solids. Through systematic manipulation of previously published liquid chromatography tandem mass spectrometry methods; this study developed an extraction protocol with optimized recovery efficiencies for varied manure substrates. The method includes a two-step, liquid-solid extraction using 10 mL of 0.1 M EDTA-McIlviane buffer followed by 10 mL of methanol. Antibiotics recoveries from unprocessed manure, separated liquids, separated solids, and heat-treated solids using the two-step extraction method had relative standard deviations < 30% for all but ceftiofur. Total antibiotic recoveries were 67–131% for tetracyclines, 56% for sulfonamide, 49–53% for macrolides, and 1.3–66% for β-lactams. This is the first study to use one protocol to assess four classes of antibiotics in liquid and solid manure fractions. This study allowed for more precise risk assessment of antibiotic transport in manure waste stream applied to fields as a liquid or solid compost.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2025

Solid Wastes from Geothermal Energy Production and Implications for Direct Lithium Extraction

Direct lithium extraction (DLE) of brines after geothermal power production offers opportunities to produce environmentally benign “green” lithium; however, some environmental impact is inevitable. We examined solid waste production at geothermal power plants in southern California that are also locations for planned DLE facilities. Currently, the geothermal plants in this region produce approximately 79,800 metric tons (wet weight) per year of solid waste, which represents about 28 metric tons per GWh of net electricity production or approximately 500 mg solids per kg geothermal brine. Approximately 15% of this waste requires management as hazardous waste. Solids produced during power production represent about 0.2% of the total dissolved solids in the brine. Lithium production will require the removal of silica, iron, and other metals as part of the DLE process. Using a mass balance approach, we calculate that precipitation of silica and metals could produce up to an additional 6800 mg solids per kg brine. Calcium occurs at very high concentrations, and the amount of solids disposed in landfills will be dependent on the amount of calcium removed during lithium recovery. Our analysis shows that evaluation of brine chemistry in the context of the DLE process is useful for evaluating the potential solid waste impacts of producing lithium from brines.

42 ENGINEERING↗

NASA NTRS1973

Fundamental equations of a mixture of gas and small spherical solid particles from simple kinetic theory.

The fundamental equations of a mixture of a gas and pseudofluid of small spherical solid particles are derived from the Boltzmann equation of two-fluid theory. The distribution function of the gas molecules is defined in the same manner as in the ordinary kinetic theory of gases, but the distribution function for the solid particles is different from that of the gas molecules, because it is necessary to take into account the different size and physical properties of solid particles. In the proposed simple kinetic theory, two additional parameters are introduced: one is the radius of the spheres and the other is the instantaneous temperature of the solid particles in the distribution of the solid particles. The Boltzmann equation for each species of the mixture is formally written, and the transfer equations of these Boltzmann equations are derived and compared to the well-known fundamental equations of the mixture of a gas and small solid particles from continuum theory. The equations obtained reveal some insight into various terms in the fundamental equations. For instance, the partial pressure of the pseudofluid of solid particles is not negligible if the volume fraction of solid particles is not negligible as in the case of lunar ash flow.

Pai, S. I.↗

NASA NTRS1995

Solid film lubricants and thermal control coatings flown aboard the EOIM-3 MDA sub-experiment

Additional experimental data were desired to support the selection of candidate thermal control coatings and solid film lubricants for the McDonnell Douglas Aerospace (MDA) Space Station hardware. The third Evaluation of Oxygen Interactions With Materials Mission (EOIM-3) flight experiment presented an opportunity to study the effects of the low Earth orbit environment on thermal control coatings and solid film lubricants. MDA provided five solid film lubricants and two anodic thermal control coatings for EOIM-3. The lubricant sample set consisted of three solid film lubricants with organic binders one solid film lubricant with an inorganic binder, and one solid film lubricant with no binder. The anodize coating sample set consisted of undyed sulfuric acid anodize and cobalt sulfide dyed sulfuric acid anodize, each on two different substrate aluminum alloys. The organic and inorganic binders in the solid film lubricants experienced erosion, and the lubricating pigments experienced oxidation. MDA is continuing to assess the effect of exposure to the low Earth orbit environment on the life and friction properties of the lubricants. Results to date support the design practice of shielding solid film lubricants from the low Earth orbit environment. Post-flight optical property analysis of the anodized specimens indicated that there were limited contamination effects and some atomic oxygen and ultraviolet radiation effects. These effects appeared to be within the values predicted by simulated ground testing and analysis of these materials, and they were different for each coating and substrate.

Murphy, Taylor J.↗

NASA NTRS1971

Detection of Pollution Caused by Solid Wastes

To develop a means of detecting pollution, it s necessary to know something about the source and nature of the pollution. The type of pollution rising from solid wastes differs considerably from hat from liquid wastes or that from gaseous wastes ni its effect on the immediate environment. It may be "defined" by a series of negatives. When solid wastes are discarded on land, the resulting pollution is not land pollution in the sense of air and water pollution. For one thing, the solid wastes do not become a "part" of the land in that the wastes are neither intimately mixed nor homogenized into the land as are liquid and gaseous wastes into their respective media. The waste particles retain not only their chemical identity but also their visible (i.e., physical) characteristics. When buried, for example, the soil is under, above, and around the solids, because the wastes are there as discrete units. Secondly, solid wastes neither diffuse nor are they carried from the place at which they were deposited. In other words they remain stationary, providing of course the disposal site is land and not moving water. In a given area, solid wastes be not distributed uniformly over that area. Even the solid wastes falling into the specification of letter meets these specifications. In contrast liquid and gaseous wastes become intimately mixed, homogenized, and even dissolved in their media. Because solid wastes remain stationary, pollution constituted by their presence is highly localized and heavily concentrated, even to the extent that the pollution could be termed "micro" when compared to the macro-pollution arising from liquid and gasequs wastes.

Golueke, Clarence G.↗

NASA NTRS2008

Solid-State High-Temperature Power Cells

All-solid-state electrochemical power cells have been fabricated and tested in a continuing effort to develop batteries for instruments for use in environments as hot as 500 C. Batteries of this type are needed for exploration of Venus, and could be used on Earth for such applications as measuring physical and chemical conditions in geothermal and oil wells, processing furnaces, and combustion engines. In the state-of-the-art predecessors of the present solid-state power cells, fully packaged molten eutectic salts are used as electrolytes. The molten-salt-based cells can be susceptible to significant amounts of self-discharge and corrosion when used for extended times at elevated temperatures. In contrast, all-solid-state cells such as the present ones are expected to be capable of operating for many days at temperatures up to 500 C, without significant self-discharge. The solid-state cell described here includes a cathode made of FeS2, an electrolyte consisting of a crystalline solid solution of equimolar amounts of Li3PO4 and Li4SiO4, and an anode made of an alloy of Li and Si (see figure). The starting material for making the solid electrolyte is a stoichiometric mixture of Li3PO4, SiO2, and Li3CO2. This mixture is ball-milled, then calcined for two hours at a temperature of 1,100 C, then placed in a die atop the cathode material. Next, the layers in the die are squeezed together at a pressure between 60 and 120 MPa for one hour at a temperature of 600 C to form a unitary structure comprising the solid electrolyte and cathode bonded together. Finally, the lithium-alloy anode is pressure-bonded to the solid electrolyte layer, using an intermediate layer of pure lithium. In one test of a cell of this type, a discharge rate of about 1 mA per gram of cathode material was sustained for 72 hours at a temperature of about 460 C. This is about three times the discharge rate required to support some of the longer duration Venus-exploration mission scenarios.

Whitacre, Jay↗