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353 Uppsatser om Chemical precipitation - Sida 11 av 24

Påverkande faktorer för grotens fukthalt

The aim of this study was to investigate how seasonal variations affect the quality of logging residues. The study was hosted by VIDA Energy. Logging residues can be processed and transported within different systems. Today the dominant systems are chipping at landing and bulk transportation of logging residues. In these systems the handling of the logging residues are carried out in the same manner up to the landings. Moisture content at the time of chipping is the primary quality parameter. Fine fractions of logging residues are strongly dependent on moisture content in storage.

Modellering av indunstning på Södra Cell Mönsterås

Evaporation is a part of the chemical recovery department at wood pulping mills. The purpose of evaporation is to remove water from the black liquor, which makes the liquor combustible. The process is very energy demanding, and having a well-functioning model of the system is of greatest interest. The model can then be used to study energy consumption and to test different control strategies. Two models have been developed during the master thesis.

Koncentrisk hämning och stimulans av bakterietillväxt i agarkulturer

The aim of this study is to elucidate factors that effect growth of Sarcina lutea and Bacillus subtilis, exposed to the growth inhibitor SDS (Sodiumdodecylsulfat). Agar diffusion experiments revealed repeated, concentric zones of inhibition and stimulation upon exposure to Sodiumdodecylsulphate or to Amoxicillin. Temperature, nutrient concentration and inhibitor concentration were controlled. Formation of successively repeated zones of inhibition, stimulation, inhibition and stimulation is discussed: ? The extension of the primary inhibition zone is due to the concentration of applied Sodium dodecyl sulphate.? Immediately outside the primary inhibition zone the bacteria have access to diffusing nutrients that have not been consumed in the primary inhabitation zone.? In zones of dense bacterial growth the bacteria may produce inhibiting substances, affecting growth of bacteria in adjacent zones.? In zones of dense bacterial growth the nutrients will soon become depleted, thus affecting bacteria in adjacent zones..

Wallenius waters AOT luftrenare

This bachelors thesis was made forWallenius Water AB to develop a basisfor an Airpurifier prototype. Wallenius Water isone of the world's leading environmentaltechnology companies engaged inchemical-free water treatment based onUV-radiation. The thesis aim was toproduce a basis for a prototype that canbe used in three applications:Standalone, RAS systems and ventilationsystems. The work includes anintroductory description of the theorybehind AOP technology based on aliterature review on the subject. Asurvey of products currently on themarket and a product specification hasbeen used as the basis for thepreparation of a number of concepts inthis report.

Sha Jun

The agriculture in Sweden today uses chemical substances to control vermin, weed and diseases. This usage shows through polluted subsoil water and trace elements in the food we eat. There?s a risk that additional symptoms will arise in the future. Our product Sha Jun, developed in 2006-2007, is an attempt to try and minimize the need of chemicals in the agriculture. The idea started with the attempt to minimize the usage of pesticides on the cropland.

Dagvatten i Märsta : förslag till anläggning för ekologisk hantering samt metodöversikt

Stormwater in urban areas has been treated as a problem for a long time. The large proportion of impermeable surfaces inhibits the water from infiltrating in the ground to the same extent that it does in nature. This causes intensive surface flow during rain, which in turn causes inconveniences such as decreased accessability, floods and increased risk of desease spreading. Drainage through pipes is the traditional and usually functional metod for storm water disposal. That is as long as water flows are moderate. But precipitation varies naturally in amount and intensity and additional impermeable surfaces make some pipes insufficient for heavy or lasting precipitation.

Utvärdering av regnmätning och droppstorleksfördelning från en distrometer

Nederbördsmätning är viktigt inom många områden och en relativt ny teknik är enoptisk distrometer som med hjälp av laserteknik mäter nederbördspartiklarnasdroppstorlek och fallhastighet. Syftet med detta arbete var att undersöka hur välThies distrometer stämmer överens med nederbördsmätning från ett vippkärl ochmanuella mätningar från institutionen för geovetenskaper vid Uppsala universitet.Institutionen för geovetenskaper överväger att gå över till denna teknik och därmedbehövdes distrometern utvärderas för olika faktorer som kan påverka instrumentet.Vid jämförelse mellan instrumenten visade det sig att distrometern totalt sett samladein mer nederbörd än de andra mätarna. Det är svårt att avgöra vad skillnaden mellaninstrumenten kan bero på men felkällor så som avdunstning och vätning hos vippkärletoch manuella mätningar kan ge mindre nederbörd. En annan orsak kan varafelkalibrering av datan från distrometern. Inga samband hittades för vindhastighet,vindriktning och typ av nederbörd mellan de tre instrumenten.En vidare undersökning gjordes för droppstorleksfördelningen för att ge exempelpå fördelar med en distrometer.

Röd Glöd : Granaternas betydelse under yngre järnålder med fokus på Gamla Uppsala

During an excavation at Old Uppsala 571 raw garnets was found. In comparison with similar fragments from other sites in Sweden my aim was to prove a completely domestic production of garnets for cloisonné work. I have chosen to look at the archaeological sites of Old Uppsala, Valsta, Slöinge and Paviken and more closely at the material from Old Uppsala and Valsta. My theoretical framework has been to look at the garnets own agency in the contemporary society.Garnet cloisonné was a popular jewellery form during the Merovingian period on the continent although it came to an end in the early 7th century. It was during this time in Scandinavia a new sort of garnet, technique and paste was introduced and the garnet cloisonné was profoundly used for the gear of the elite and ritual objects.

Utvärdering av datorprogram för användning vid dagvattenutredningar

The main object of this diploma work thesis is about how computer programs can bea tool to use for work on stormwater investigations. The advantage of using acomputer program compared with calculations made by hand is evaluated anddiscussed. The computer programs that have been used for studies and a sequence oftesting of the possibilities are Autodesks Storm and Sanitary Analysis and DHIs MikeUrban.Focus on sustainable development now permeates the building industry. As a resultstormwater investigations have been conducted in an increasing extent the recentyears. Stormwater is water produced due to precipitation, such as rain and snowmelt.Stormwater investigations normally contain descriptions of existing land use, plannedland use and suggestions of measures and technical solutions for the future disposal ofstormwater.The initial part of the thesis consisted of literature studies on stormwater andstormwater investigations to understand the science.

Skogens produktionsvärden och dess betydelse för Sveriges ekonomi

The forest is characterized by many different values such as those related to forest productivity which are of a big importance for Swedish economy. History has proved that forest resources had helped the country in the transition from the agricultural to the industrial society. Today Swedish forest industry is among the strongest in Europe and significantly contributing to the Swedish export. The industry provides many direct and indirect job opportunities and is one of the biggest employers in the industry sector. It is also worth to notice that the forest can also generate an additional income for the owners, even if the forestry isn?t their primary income source.

Bättre åtkomst till avverkningstrakter med anpassat marktryck från avverkningsmaskinerna

The global climate-change means increasing mean-temperature and higher precipitation in Sweden, which leads to shorter periods of frozen ground in the forest. At the same time the harvesting machines are getting bigger and more powerful. The forest industry aim at an even wood flow, and the ground damage has to be as low as possible. The two biggest causes for ground-damage is the bearing capacity of the forest ground and the ground-pressure of the harvesting machines. The aim of this study was to find out some rules for the machine choice considering ground pressure, when harvesting on ground with low bearing capacity.A field study, using a Valmet 890.3 forwarder, was carried out where different ground pressures and their effect on the ground were tested on two different types of ground.Additionally, an inventory of damaged harvesting grounds was made.

Stress och akrolin - ett irriterande ämne : Påverkan av akrolin på symptomförekomst bland hög- och lågstressade personer med självrapporterad god hälsa

Överkänslighet mot kemiska ämnen i vår omgivning skapar hälsoproblem som ?sick building syndrome? samt ?multiple chemical sensitivity?. Båda tros kunna starta efter långvarig lågdos-exponering av kemikalier som till slut resulterar i en överkänslighet. Symptombilden är blandad och diagnostiseringen svår. Bland annat stress verkar vara en påverkande faktor liksom det kemestetiska hudsinnet.

Varför är Bivarödsånsvatten så brunt?

The river Bivaröd is one of the river Helgeån tributaries which has the highest and the fastest increase in water colour. The reason behind this increase is unclear but several factors have been suggested to affect this pattern. In this work, I studied the role of land use, iron and precipitation for water colour increase in river Bivaröd for the period 1976 -2011. Data from a field study along with data from SRK for river Helgeån were used for the analyses. The results showed that both water colour and iron concentration increase and that there is a strong correlation between these two variables.

Willingness to pay for improved maize seeds among smallholder farmers : a study of the input factor market in Kenya

Kenya is considered to be a developing country. This means that basic needs such as nutrition are not met for an extended period of time (www, Sida 1, 2012). Approximately half of the population is living under the poverty line (www, CIA 1, 2012). Agriculture is the largest sector in the country, employing 75% of the population. These are thereby directly dependent on the sufficiency of outputs received.

Erfarenheter av utedrift med köttdjur i Sverige och Kanada :

Beef cattle wintering outdoors should be provided a shelter, e.g. a type of barn or corresponding. This type of production requires appropriate soil types and secured animal welfare. For example, a clean and dry resting place needs to be provided to the animals. To receive an exemption for buildings the farmer has to have something equivalent that provides an adequate shelter.

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