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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 1,009 records · Page 56
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Re-thinking incentives and penalties: Economic aspects of waste management in Italy

Highlights: • We focused on the dynamics the formation of operational costs of waste management. • We provide the basic elements to compose a picture of economic management. • We present a reflection on the last hidden costs associated with the consumption of goods and packaging. • Reduction of waste production. - Abstract: This paper focuses on the dynamics the formation of operational costs of waste management in Italy and the effect of economic measures. Currently incentives and penalties have been internalized by the system no differently from other cost items and revenues. This has greatly influenced the system directing it towards solutions that are often distant from the real environmental objectives. Based on an analysis of disaggregated costs of collection treatment and recovery, we provide the basic elements to compose a picture of economic management in various technical–organizational scenarios. In the light of the considerations contained in the paper it is proposed, e.g. for controlled landfills, that the ecotax, currently based on weight, could be replaced by one based on the volume consumption. Likewise, for tax reduction on disposal system, instead a pre-treatment might ask an environmental balance of the overall system. The article presents a reflection on the last hidden costs associated with the consumption of goods and packaging, and how to reduce waste production is the necessary path to be followed in ecological and economic perspectives.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Economic aspects of thermal treatment of solid waste in a sustainable WM system

Highlights: • Provides a comprehensive review of the applied economic literature dedicated to WtE. • Offers a detailed discussion of the main assumptions that characterize alternative positions. • Highlights the most robust achievements obtained by the applied economic research in this field. • Compares economic and non-economic valuation techniques. - Abstract: This paper offers a systematic review of the literature of the last 15 years, which applies economic analysis and theories to the issue of combustion of solid waste. Waste incineration has attracted the interest of economists in the first place concerning the comparative assessment of waste management options, with particular reference to external costs and benefits. A second important field of applied economic research concerns the market failures associated with the provision of thermal treatment of waste, that justify some deviation from the standard competitive market model. Our analysis discusses the most robust achievements and the more controversial areas. All in all, the economic perspective seems to confirm the desirability of assigning a prominent role to thermal treatments in an integrated waste management strategy. Probably the most interesting original contribution it has to offer concerns the refusal of categorical assumptions and too rigid priority ladders, emphasizing instead the need to consider site-specific circumstances that may favor one or another solution.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Recovery of lithium and cobalt from spent lithium-ion batteries using organic acids: Process optimization and kinetic aspects

Highlights: • Li recovery 99.80%, Co recovery 96.46% in citric acid reductive leaching with H{sub 2}O{sub 2.} • Investigating possibility of bioleaching of LIBs by using 4 organic acids. • Comparing cavitation in ultrasonic agitation with mechanical stirrer. • Co kinetics depends on temperature: both diffusion and chemical reaction controls. •Li kinetics, all temperatures: reagent diffusion through the product layer controls. - Abstract: An environmentally-friendly route based on hydrometallurgy was investigated for the recovery of cobalt and lithium from spent lithium ion batteries (LIBs) using different organic acids (citric acid, Dl-malic acid, oxalic acid and acetic acid). In this investigation, response surface methodology (RSM) was utilized to optimize leaching parameters including solid to liquid ratio (S/L), temperature, acid concentration, type of organic acid and hydrogen peroxide concentration. Based on the results obtained from optimizing procedure, temperature was recognized as the most influential parameter. In addition, while 81% of cobalt was recovered, the maximum lithium recovery of 92% was achieved at the optimum leaching condition of 60 °C, S/L: 30 g L{sup −1}, citric acid concentration: 2 M, hydrogen peroxide concentration: 1.25 Vol.% and leaching time: 2 h. Furthermore, results displayed that ultrasonic agitation will enhance the recovery of lithium and cobalt. It was found that the kinetics of cobalt leaching is controlled by surface chemical reaction at temperatures lower than 45 °C. However, diffusion through the product layer at temperatures higher than 45 °C controls the rate of cobalt leaching. Rate of lithium reaction is controlled by diffusion through the product layer at all the temperatures studied.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

A Simple Approach to the Technical Aspects of Radiosurgery Treatments

An approach to radiosurgery treatment that can be readily adopted in most radiotherapy centers with linear accelerators is presented. In our institution, a Leksell-type of neurosurgical frame, a computed tomography scanner, locally fabricated cones, and 6 MV X-ray beams are used to perform radiosurgery treatments. Collimated arcs with dose distributions that conform to the shape of the lesion in the transverse and the sagittal planes are used. It is argued that the uncertainties in the localization of the isocenter within a lesion and the specifications of the size of the target volume do not justify high precision mechanical devices for most radiosurgery treatments.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2022

Computational Aspects of Single-Molecule Kinetics for Coupled Catalytic Cycles: A Spectral Analysis

Catalysis from single active sites is analyzed using methods developed from single molecule kinetics. Using a stochastic Markov state description, the observable properties of general catalytic networks of reactions are expressed using an eigenvalue decomposition of the transition matrix for the Markov process. By the use of a sensitivity analysis, the necessary eigenvalues and eigenvectors are related to the energies of controlling barriers and wells located along the reaction routes. A generalization of the energetic span theory allows the eigenvalues to be computed from several activation energies corresponding to distinct barrier-well pairings. The formalism is demonstrated accurately for model problems for a physically realistic mechanism for an alkene hydrogenation reaction on a single atom catalyst.

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

Revealing Local and Directional Aspects of Catalytic Active Sites by the Nuclear and Surface Electrostatic Potential

This work examines the prospects of using the electrostatic potential, V(r), as a descriptor in heterogeneous catalysis. In particular, the subatomic spatial resolution of the property allows for analysis of both directionality and confinement effects in surface adsorption. This feature of V(r) is used to identify adsorption sites, orientations, and energetics for metal surfaces, particles, and nanoclusters upon interactions with catalytically relevant intermediates. The use of V(r) in assessing the 3D nature of catalytic sites in low-temperature and electrocatalysis is highlighted, and future directions in catalysis design are discussed. Ultimately, we provide a critical analysis of the use of V(r) in the predictions of local adsorption susceptibilities, and we address its limitations. The link between V(r) and other established descriptors in catalysis are motivated via physical relations and theoretical derivations; close ties are established between V(r) and the d-band center (ε d ), as well as the surface site stability (BE M ). In conclusion, by comparing the performance of V(r) evaluated on isodensity contours, i.e., the surface electrostatic potential, to that of V(r) evaluated at the nucleus of an atom, we investigate the application space for a directional and an atom-localized version of the V(r) descriptor for catalyst design.

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

Exploring the Computational Aspects of Propylene Oligomerization Catalysis Using M′ 2 M Type Trimetallic MOF Nodes

Metal-organic frameworks have emerged as promising materials in the field of catalysis. They offer an optimal ground for screening catalysts and tailoring their catalytic properties. Here, in this work, via density functional theory (DFT) calculations, we investigated the catalytic activity of the trimetallic MOF nodes, M' 2 M for propylene oligomerization, by varying the active metal M from Sc to Cu with M' being Fe, aiming to grasp the impact of altering the active atoms on the catalyst's activity. Additionally, we examined how substituting the spectator atom, M', with other transition metals, i.e., from Sc to Cu, affects these energy barriers, keeping Ni as the active metal. We proposed several cases with lower or comparable energy barriers to the experimentally reported Fe 2 Ni trimetallic MOF node. In addition, we found a correlative relationship between spin-density from natural population analysis and energy barriers in the realm of C-C bond formation, whereby an elevation in spin-density is found to be inversely proportional to the magnitude of the energy barriers. Moreover, we calculated the energy barriers for C-C coupling and beta-hydride elimination using multireference NEVPT2 calculations on top of the CASSCF wave function to validate the rate-determining step that is predicted by DFT.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗