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- Cocciolo, Serena, 1987-
(författare)
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Participatory Governance and Public Service Provision
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- How do Community Contribution Requirements Affect Local Public Good Provision? Experimental Evidence from Safe Water Sources in Bangladesh We exploit the random assignment of communities selected to receive a safe drinking water program to various contribution requirements: cash, labor or no requirement to contribute. Imposing a cash contribution requirement greatly decreases program take-up, while imposing a labour contribution does not. Program impact is correspondingly lower under the cash contribution requirement than under the labour contribution requirement or contribution waiver. The cash contribution requirement screens out communities with low arsenic contamination, but screening does not lead to increased treatment effects on the treated. Our results suggest that there are substantial welfare gains to be made in such projects in poor communities by allowing households to contribute in labour rather than cash.
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| 2. |
- Trubetskaya, Anna, et al.
(författare)
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Characterization and reactivity of soot from fast pyrolysis of lignocellulosic compounds and monolignols
- 2018
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Ingår i: Applied Energy. - Oxford : Elsevier. - 0306-2619 .- 1872-9118. ; 212, s. 1489-1500
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Tidskriftsartikel (refereegranskat)abstract
- This study presents the effect of lignocellulosic compounds and monolignols on the yield, nanostructure and reactivity of soot generated at 1250 °C in a drop tube furnace. The structure of soot was characterized by electron microscopy techniques, Raman spectroscopy and electron spin resonance spectroscopy. The CO2 reactivity of soot was investigated by thermogravimetric analysis. Soot from cellulose was more reactive than soot produced from extractives, lignin and monolignols. Soot reactivity was correlated with the separation distances between adjacent graphene layers, as measured using transmission electron microscopy. Particle size, free radical concentration, differences in a degree of curvature and multi-core structures influenced the soot reactivity less than the interlayer separation distances. Soot yield was correlated with the lignin content of the feedstock. The selection of the extraction solvent had a strong influence on the soot reactivity. The Soxhlet extraction of softwood and wheat straw lignin soot using methanol decreased the soot reactivity, whereas acetone extraction had only a modest effect.
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| 3. |
- Trubetskaya, Anna, et al.
(författare)
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Effects of Lignocellulosic Compounds on the Yield, Nanostructure and Reactivity of Soot from Fast Pyrolysis at High Temperatures
- 2017
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Gasification offers the utilization of biomass to a wide variety of applications such as heat, electricity, chemicals and transport fuels in an efficient and sustainable manner. High soot yields in the high-temperature entrained flow gasification lead to intensive gas cleaning and can cause a possible plant shut down. The reduction of soot formation increases the overall production system efficiency and improves the economic feasibility and reliability of the gasification plant. The aim of this work is to present the effect of lignocellulosic compoundson the yield, nanostructure and reactivity of soot. Soot was produced from holocelluloses, extractives, two types of organosolv lignin (softwood and wheat straw), and lignin-derived compounds (syringol, guaiacol, p-hydroxyphenol)at temperature of 1250°Cand residence time of 0.17 sand 0.35 sin a drop tube furnace.Soxhlet extraction was performed on soot samples from pyrolysis of both lignin samplesusing acetone and methanol as a solvent.The structure of solid residues was characterized by transmission electron microscopy and Raman spectroscopy. The reactivity of soot inO2oxidation and CO2gasificationwas investigated by thermogravimetric analysis. The present results indicated that soot yields from pyrolysis of ligninfrom softwood and extractives at 1250°C with the residence time of 0.17 swere similaras shown in Figure 1. The highest soot yield was obtained from pyrolysis of wheat straw lignin and quantitatively comparable with the soot yield of hydroquinone. The presence of hydroxyl groups compared to other lignin-derived compounds representing S-and G-lignin types might enhance the soot formation.Lower soot yields were obtained from pyrolysis of cellulose and hemicellulosedue to the lower presence of inherent aromatic rings [1-3].Moreover, the soot yields from pyrolysis of potassium impregnated lignin at 1250°C with the residence time of 0.35 swere significantly lower than that of non-treated lignin samples indicating the catalytic influence of potassium inhibitinggrowth of polycyclic aromatic hydrocarbons, confirming the previous results of Umeki et al. [4]
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