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Aluminum, due to its high abundance, very attractive theoretical capacity, low cost, low (de−) lithiation potential, light weight, and effective suppression of dendrite growth, is considered as a promising anode candidate for lithium‐ion batteries (LIBs). However, its practical application is hindered due to multiple detrimental challenges, including the formation of an amorphous surface oxide layer, pulverization, and insufficient lithium diffusion kinetics in the α‐phase. These outstanding intrinsic challenges need to be addressed to facilitate the commercial production of Al‐based batteries. The native passivation layer, Al2O3, plays a critical role in the nucleation and reversibility of lithiating aluminum and is thoroughly investigated in this study using high precision electrochemical micro calorimetry. The enthalpy of crystallization of β‐LiAl is found to be 40.5 kJ mol−1, which is in a strong agreement with the value obtained by calculation using Nernst equation (40.04 kJ mol−1). Surface treatment of the active material by the addition of 25 nm of alumina increases the nucleation energy barrier by 83 % over the native oxide layer. After the initial nucleation, the added alumina does not negatively impact the reversibility at 0.1 C rate, suggesting the removal of alumina is not necessary for improving the cyclability of aluminum anode based lithium‐ion batteries. Moreover, the coulombic efficiencies are also found to be slightly higher in the alumina treated samples compared to the untreated ones. [ABSTRACT FROM AUTHOR]

Growing demand for bioenergy, biofuels, and bioproducts has increased interests in the utilization of biomass residues from forest treatments as feedstock. In areas with limited history of industrial biomass utilization, uncertainties in the quantity, distribution, and cost of biomass production and logistics can hinder the development of new bio-based industries. This paper introduces a new methodology to quantify and spatially describe delivered feedstock volumes and costs across landscapes of arbitrary size in ways that characterize operational and annual management decision-making. Using National Agricultural Imagery Program (NAIP) imagery, the forest is segmented into operational-level treatment units. A remote sensing model based on NAIP imagery and Forest Inventory and Analysis plot data are used to attribute treatment units with stand-level estimates of basal area, tree density, aboveground biomass, and quadratic mean diameter. These methods are applied to a study site in southwestern Colorado to assess the quantity and distribution of treatment residue for use in bioenergy production. Results from the case study demonstrate how this generalized approach can be used in the analysis and decision-making process when establishing new bioenergy industries that use forest residue as feedstock. Key words: forest biomass, stand characteristics, treatment residue, bioenergy, stand delineation. La demande grandissante pour la bioenergie, les biocarburants et les bioproduits a augmente l'attrait pour l'utilisation comme matiere premiere de la biomasse residuelle generee par les traitements sylvicoles. Dans les regions qui ont une experience limitee de l'utilisation industrielle de la biomasse, les incertitudes concernant la quantite, la distribution ainsi que le cout de production et la logistique de la biomasse peuvent nuire au developpement de nouvelles bio-industries. Cet article presente une nouvelle methodologie pour quantifier et decrire spatialement les volumes et les couts de la matiere premiere livree dans un paysage aux dimensions arbitraires et d'une facon qui caracterise le processus de prise de decision operationnelle et annuelle d'amenagement. A l'aide des images du Programme national d'imagerie agricole (NAIP), la foret a ete segmentee en unites de traitement sur la base des contraintes spatiales definies par les utilisateurs. Un modele de teledetection fonde sur les images du NAIP et sur les donnees des places echantillons du Programme d'analyse et d'inventaire forestiers est utilise pour attribuer les unites de traitement avec des estimations a l'echelle du peuplement de la surface terriere, de la densite des arbres, de la biomasse aerienne et du diametre de la tige de surface terriere moyenne. Ces methodes sont appliquees a une station experimentale dans le sud-ouest du Colorado pour evaluer la quantite et la distribution des residus de traitement pour la production de bioenergie. Les resultats de cette etude de cas demontrent comment cette approche generalisee peut etre utilisee dans le processus d'analyse et de prise de decision lors de l'etablissement de nouvelles industries bioenergetiques qui utilisent les residus de la foret comme matiere premiere. [Traduit par la Redaction] Mots-cles: biomasse forestiere, caracteristiques des peuplements, residus de traitement, bioenergie, delimitation des peuplements., 1. Introduction The interior western United States (US) has experienced growing interest in using forest biomass as a renewable source of energy. Historically, the use of forest biomass has been [...]

Two ground-based timber harvesting methods have been commonly used for beetle-kill salvage treatments after a bark beetle epidemic in northern Colorado. A "lop and scatter" method uses a mobilized stroke delimber to delimb and buck trees at the stump, leaving tree tops and limbs on the forest floor, while a whole-tree harvesting method brings the entire tree to the landing where it is delimbed and bucked, and thus produces logging residue piles at the landing as a byproduct. We conducted a detailed comparative time study of the two harvesting methods to develop productivity and cost models and compared the performance of the two methods under various site conditions. We applied the productivity and cost models to lodgepole pine forest stands totaling 3400 hectares of the Colorado State Forest State Park to estimate salvage harvesting costs for each forest stand and identify the least costly harvesting options. The results show that the estimated stump-to-truck timber production costs were $30.00 per oven dry ton (odt) for lop and scatter and $23.88 odt-1 for the whole-tree method in our study harvest unit. At the forest level, the estimated average stump-to-truck costs were $54.67 odt-1 and $56.95 odt-1 for lop and scatter and whole-tree harvesting, respectively. Skidding distance and downed trees affect the harvesting costs of both methods, but their influence appears to be more significant on the whole-tree method. [ABSTRACT FROM AUTHOR]