Search results for "vih"

Ilmastonmuutos ja yliopisto

2017

Activated carbon from hydrolysis lignin: Effect of activation method on carbon properties

2022

This study presents the effects of different activation methods to produce activated carbon from the hydrolysis lignin. Pretreatment of the feedstock with common mineral acids (HCL, HNO3, and H3PO4), different steam rates for physical activation, and different chemical activating agents (ZnCl2, Na2CO3, and KOH) for chemical activation were investigated. The pretreated biomass was carbonized and activated in one-stage process and the surface characteristics, such as total pore volume, pore size distribution and specific surface area, were investigated. The results showed that the activated carbon surface properties were not greatly affected by acid pretreatment. Brunauer-Emmett-Teller (BET) …

Sodan ja rauhan rajoilla : identiteettipoliittinen keskustelu suomalaisissa sanomalehdissä jatkosodan päättyessä syksyllä 1944

2003

Koetun terveyden yhteys elämän tarkoituksellisuuteen 83-92-vuotiailla jyväskyläläisillä

1999

Enhancing methane production in a farm-scale biogas production system

2003

Biokaasuteknologiaa pidetään maataloudessa lisääntyvässä määrin lupaavana tekniikkana tuottaa uusiutuvaa energiaa ja minimoida päästöjä ympäristöön. M.Sc. Prasad Kaparaju arvioi väitöstyössään menetelmiä, jotka tehostaisivat metaanintuottoa tilakohtaisessa biokaasuntuotantojärjestelmässä.Hyvin suunniteltu agroteollisuuden jätteiden ja sivutuotteiden käyttö lisää biokaasun tuotantoa maatilakohtaisissa biokaasulaitoksissa ja parantaa ravinteiden kierrätettävyyttä. Maatilakohtaisten prosessien metaanintuotannon maksimoimiseksi työ kohdistui erityyppisten jätemateriaalien metaanintuotannon ja prosessivaikutusten tutkimiseen. Lisäksi tutkittiin erialaisia fysikaalisia ja kemiallisia menetelmiä, …

Ajatuksia ilmastoetiikasta

2013

Ajatuksia ilmastoetiikasta, Teea Kortetmäki, Arto Laitinen & Mikko Yrjönsuuri, 4 Ilmastonmuutos yhteiskuntafilosofian ongelmana, Lauri Lahikainen, 21 Ilmastokysymys ja demokraattinen päätöksenteko, Simo Kyllönen, 35 YK:n ilmastokokousten eettiset kysymykset, Teea Kortetmäki, 63 Oikeudenmukaisuus ja vahingonteko ilmastokontekstissa, Teppo Eskelinen, 84 Osallisuusvastuu ilmastonmuutoksesta, Säde Hormio, 103 Ilmaston lämpeneminen, etiikka ja kulttuurikritiikki, Markku Oksanen, 120 Ilmastonmuokkauksen etiikasta, Sanna Joronen, 137 Kirjoittajatiedot, 153

Characterization of Cobalt Catalysts on Biomass-Derived Carbon Supports

2017

Cobalt catalysts are known to have a high activity and selectivity in the Fischer–Tropsch reaction converting synthesis gas to higher hydrocarbons (C5+). These catalysts have been supported by different porous materials. Porous carbon materials like activated carbon (AC) have physical and chemical surface properties that affect the preparation of supported metal catalysts and can easily be tailored. In this study, AC was produced by carbonization and steam activation of lignin, a waste fraction from the Kraft pulping process. A series of Co/AC-catalysts was produced and characterized by several techniques. According to the results, tailored properties (high surface area, mesoporosity) were …

Lignin-based activated carbon-supported metal oxide catalysts in lactic acid production from glucose

2021

In this study, heterogeneous biomass-based activated carbon-supported metal oxide catalysts were prepared and tested for lactic acid production from glucose in aqueous solution. Activated carbons were produced from hydrolysis lignin by chemical (ZnCl2) or steam activation and modified with a nitric acid treatment and Sn, Al, and Cr chlorides to obtain carbon-based metal oxide catalysts. The modification of the carbon support by nitric acid treatment together with Sn and Al oxides led to an increase in lactic acid yield. The highest lactic acid yield (42%) was obtained after 20 minutes at 180 °C with the Sn/Al (5/2.5 wt.%) catalyst on steam-activated carbon treated by nitric acid. Reusabilit…

Effects of self-efficacy on healthy eating depends on normative support: a prospective study of long-haul truck drivers

2017

Purpose Fruit and vegetable intake (FV) is insufficient in industrialized nations and there is excess of discretionary food choices (DC; foods high in fat, sugar, and salt). Long-haul truck drivers are considered a particularly at-risk group given the limited food choices and normatively reinforced eating habits at truck rest-stops. Self-efficacy and normative support are key determinants of eating behavior yet the processes underlying their effects on behavior are not well understood. We tested the direct and interactive effects of self-efficacy and normative support on healthy eating behaviors in long-haul truck drivers in a prospective correlational study. Method Long-haul truck drivers …

Preconditioning of the generalist herbivore Trialeurodes vaporariorum to greenhouse monocultures and its subsequent performance on wild polycultures

2016

Generalist herbivores can face many challenges when choosing their host plant. This can be particularly difficult if their choice and performance are affected by host experience. Greenhouse whitefly, Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae), is an invasive generalist herbivore, which has established in year-round greenhouses at northern latitudes where it cannot overwinter outdoors. It mainly uses crops such as cucumber (Cucumis sativus L.), tomato (Solanum lycopersicum L.), and ornamentals as host plants. However, every summer the insect escapes greenhouses and is exposed to natural vegetation. We evaluated the performance of T. vaporariorum on diverse vegetation outside…