26 research outputs found
Mono-, bi-, and tri-metallic Ni-based catalysts for the catalytic hydrotreatment of pyrolysis liquids
Catalytic hydrotreatment is a promising technology to convert pyrolysis liquids into intermediates with improved properties. Here, we report a catalyst screening study on the catalytic hydrotreatment of pyrolysis liquids using bi- and tri-metallic nickel-based catalysts in a batch autoclave (initial hydrogen pressure of 140 bar, 350 A degrees C, 4 h). The catalysts are characterized by a high nickel metal loading (41 to 57 wt%), promoted by Cu, Pd, Mo, and/or combination thereof, in a SiO2, SiO2-ZrO2, or SiO2-Al2O3 matrix. The hydrotreatment results were compared with a benchmark Ru/C catalyst. The results revealed that the monometallic Ni catalyst is the least active and that particularly the use of Mo as the promoter is favored when considering activity and product properties. For Mo promotion, a product oil with improved properties viz. the highest H/C molar ratio and the lowest coking tendency was obtained. A drawback when using Mo as the promoter is the relatively high methane yield, which is close to that for Ru/C. H-1, C-13-NMR, heteronuclear single quantum coherence (HSQC), and two-dimensional gas chromatography (GC x GC) of the product oils reveal that representative component classes of the sugar fraction of pyrolysis liquids like carbonyl compounds (aldehydes and ketones and carbohydrates) are converted to a large extent. The pyrolytic lignin fraction is less reactive, though some degree of hydrocracking is observed
Relations between chronic regulatory focus and future time perspective: Results of a cross-lagged structural equation model
Future time perspective - the way individuals perceive their remaining time in life - importantly influences socio-emotional goals and motivational outcomes. Recently, researchers have called for studies that investigate relationships between personality and future time perspective. Using a cross-lagged panel design, this study investigated effects of chronic regulatory focus dimensions (promotion and prevention orientation) on future time perspective dimensions (focus on opportunities and limitations). Survey data were collected two times, separated by a 3. month time lag, from 85 participants. Results of structural equation modeling showed that promotion orientation had a positive lagged effect on focus on opportunities, and prevention orientation had a positive lagged effect on focus on limitations
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Denitration of High Nitrate Salts Using Reductants
This report describes work conducted by Pacific Northwest National Laboratory (PNNL), in conjunction with Idaho National Engineering and Environmental Laboratory (INEEL), to remove nitrates in simulated low-activity waste (LAW). The major objective of this work was to provide data for identifying and demonstrating a technically viable and cost-effective approach to condition LAW for immobilization (grout)
Deciphering controls for debrisâflow erosion derived from a LiDARârecorded extreme event and a calibrated numerical model (RoĂbichelbach, Germany)
Work-related use of information and communication technologies after hours and focus on opportunities: The moderating role of work-family centrality
A lifespan perspective on leadership
In this chapter, we present a lifespan model of leadership that outlines how leader and follower age as well as age-related changes in leader traits and characteristics, leader behaviors, and follower attribution and identification processes may influence leadership effectiveness. First, we describe how leader traits and characteristics change with age and how these developmental changes may impact on leader behaviors and, subsequently, leadership effectiveness. Specifically, we discuss age-related changes in leadersâ task competence, interpersonal attributes, and motivation to lead. We particularly focus on how generativity-a set of interconnected motives pertaining to establishing and guiding future generations-may emerge as an important concern among older leaders. Second, we review theoretical approaches that help explain how and why leader age and age-related traits and characteristics, follower age, as well as leader-follower age differences may influence follower attribution and identification processes. Third, we outline a number of boundary conditions of the effects proposed by our lifespan model of leadership, including leader-follower relationship duration, situational characteristics, as well as the cultural, social, and historical context. We conclude the chapter by discussing our modelâs implications for future research and organizational practice