Sökresultat:
1184 Uppsatser om Plant Simulation - Sida 19 av 79
Increased growth in Norway spruce (Picea abies (L.) Karst.) through small annual additions of nitrogen (N) fertilizer
This project investigated how elevation and vegetation type influences variation in plant litter phenolic content and protein precipitation capacity among and within common plant species for two different vegetation types, heath and meadow, in a subarctic ecosystem in the Abisko region of northern Sweden. As nutrient availability generally decreases with increasing elevation as a result of decreasing temperature, I hypothesised that phenolic content would increase with elevation and be higher on the heath than the meadow. To test this, the total phenolic content and protein precipitation capacity was estimated in leaf litter from 13 species in both heath and meadow vegetation across an elevational gradient ranging from 500 to 1000 meters above sea level (m.a.s.l.) in the study region. The results showed that elevation and vegetation type both had a strong impact on both variables. Total phenolic concentrations decreased with elevation for the meadow, and were greater for the heath than the meadow.
Molecular testing of raspberry plants infected with tomato black ring virus
Nematode-transmitted plant viruses (such as nepoviruses) cause great economically losses in commercially important plants such as tomatoes, grapevines and raspberries all over the world. To avoid spread of the viruses the interest in mapping the viruses has increased. One of the important nepoviruses infecting European red raspberries (Rubus idaeus) is Tomato black ring virus (TBRV). TBRV has earlier been confirmed in raspberry samples from Belarus by ELISA and the aim of this bachelor degree project was to confirm these results by amplifying, cloning and sequencing the coat protein (CP) gene of the virus. In total eight viral cDNA samples, from two different raspberry samples, were amplified and sequenced.
"Guud, vad tråkigt." : Matematik och elevmotivation
Drinking water is produced from raw water and is either from groundwater or surface water. This thesis aims to find out if the cleaning process of raw water is sufficiently effective. This is important because consumers are otherwise at risk of waterborne infection caused by pathogens. There are three groups of pathogens; bacteria, virus and parasite. These have different characteristics which mean that they require different water treatment to be separated.
I huvudet på en naturkunskapslärare : Elevernas intresse- problem eller resurs?
Drinking water is produced from raw water and is either from groundwater or surface water. This thesis aims to find out if the cleaning process of raw water is sufficiently effective. This is important because consumers are otherwise at risk of waterborne infection caused by pathogens. There are three groups of pathogens; bacteria, virus and parasite. These have different characteristics which mean that they require different water treatment to be separated.
Analys av massapumps- och mixerarbete vid Metsä Board Sverige AB, Husums Fabriker : Energibesparingsåtgärder vid blekeri 4 & 5 med jämförelse mot ny utrustning
Husums plant has a selection of different pulp pumps at bleaching plant 4 and 5. The displacement- (HC-pump, Sund Defibrator PTD-60) and centrifugalpumps (MC-pump, MCA 42-200, MCP 30/20) are of interest in this report. The centrifugal pumps are controlled by throttle valves, which result in an energy loss. Chemical mixers are used to mix ClO2 into the pulp before proceeding into a holding tower where the bleaching process occurs.The energy demand of the different positions has been measured or calculated to be used in comparisons against new equipment. Quotations were requested and delivered from Valmet and Sulzer.
Vattenflödets betydelse för fångster av lekvandrande lax (Salmo salar) och öring (Salmo trutta) : En utvärdering av laxfällan vid vattenkraftverket i Forshaga
Many watersheds have lost stocks of migrating fish species because of the development of hydroelectric plants and other fragmenting barriers. The remaining stocks of migrating Atlantic salmon (Salmo salar) and brown trout (Salmo trutta) in River Klarälven, Sweden are five times smaller compared to one hundred years ago. A fish-trap at the hydroelectric plant in Forshaga has been vital for the continued existence of the stocks. This is the first hydroelectric plant of eight, blocking the way to the spawning grounds. Spawners are collected in the trap for both hatchery and transport by truck upstream and past seven more hydroelectric plants to the spawning grounds, where they are released for possible natural reproduction.
Ny teknik för småskalig kraftvärme : - med fokus på Organisk RankineCykel (ORC)
As a part of the fight against the global warming the energy production needs to be more efficient and redirected towards sustainable options. One alternative is cogeneration, which means that electricity and heat is produced in one plant. The purpose with this survey is to examine if there are any commercial available combined heat and power techniques, based on combustion of solid moist biomass, which are suitable to small-scale applications. The technique must be able to produce between 2 and 10 MW thermal and the heat demand is a Swedish district-heating system. When already published reports had been studied, the Organic Rankine Cycle (ORC) was chosen as the most suitable technique.
Modellering av reflektans från ett sockerbetsbestånd med hjälp av en strålningsmodell
The Multispectral Canopy Reflectance Model (MCRM) by Kuusk (1995) has beenused to simulate the reflectance of a sugarbeet canopy. The simulated reflectancevalues show high absorptance in the VIS area, compared to field measurements, andhigh reflectance values in the NIR area. The errors may be due to overestimation ofclorophyll content in the sugarbeet leaves and scattered light during fieldmeasurements. The estimation of the clorophyll content where carried out using thePROSPECT-model by Jacquemoud & Baret (1990).During the vegetation period, the state of the canopy moves towards a closed canopy,with sparse vegetation in spring. The MCRM-model was used to perform a ?spring?simulation, which was compared to the original simulation.
Simulering av en framtida presslinje - en analys av design och prestanda
Problem areaAlfa Laval is a world leading company in the heat transfers area and have the vision to continue to be that in the future as well. The company has a lot of press lines where the utilization is high and also has started to become old. Prognosis shows that there is an increased demand of heat exchanger in the future. This increased demand is not something that existing lines will manage. To build new lines cost a lot of money and take time so it is essential that new lines are correct from the start and not need to be rebuilt or a lot of time spent to trim it.GoalThe goal is to achieve 100% theoretical utilization of the press (the press shall press the amount of plates it is designed for).
Utvärdering av jetomrörning : En studie gällande utvärdering av omrörningssystem vid Ekeby reningsverk
Biogas is a renewable energy produced through anaerobic digestion, which means that organic matter is degraded by microorganisms under anaerobic conditions. The produced biogas can then be used for cogeneration, electricity, heat or upgraded to vehicle gas. Eskilstuna Energy & Environment AB has four digesters at Ekeby water sewage treatment plant, Eskilstuna. One of the biogas reactor (RK4) is equipped with a jet-mixing system while the remaining digester uses top-mixing. The mixing system is an important parameter to achieve optimum operating conditions for the process regarding gas production and degree of digestion.
Vallört som växtnäringskälla : växtnäringsförsök och litteraturstudie
Russian comfrey, Symphytum x uplandicum, was tested as a plant nutrient source in a trial with tomatoes. Comfrey liquid was produced by Stiftelsen Holma i Höör. Tomato plants of the cultivar Aromata planted in a medium of soil:peat (1:1) enriched with organic nutrients and lime, were fed with comfrey liquid plus Biofer, in three different concentrations. Two different concentrations of BioRika were used as comparison, along with an unfertilized control group. In the comfrey treatment I a total amont of 1g N, 0,23 g P, 0,84 g K, was given to the tomatoes.
Kisel som växtstärkande medel : en litteraturstudie
Sammanfattning
Kisel (Si) är det näst vanligaste ämnet (drygt 25 %) i berggrunden. Bara en del av detta är tillgängligt som monokiselsyra, den form i vilken kisel är upptagbart för växter. Jordens kiselinnehåll är beroende av bergets vittring. Mycket höga halter av kisel återfinns i naturen i vulkaniska substrat (pimpsten innehåller drygt 66 % Si och scoria närmare 47 % Si), i diatomit (ett mineral bestående av resterna från encelliga kiselhaltiga alger, s.k. diatoméer) innehållande 66 % Si, scoria approximatly 47% Si), in diatomite (a mineral consisting of the remainings of single celled algae, diatoms containing < 40 % Si) and in some clays (30-60% Si).
Hållbar växtnäringshantering i Stockholms län : En aktörsanalys
Plant nutrients are important for all life on earth and are also important as fertiliser infood production all over the world. Because of this, plant nutrients are of great valuebut they also bring problems. As an example, the loss of nitrogen and phosphorusfrom agriculture and urban society's sewage systems contributes to some of today?smajor problems in water environment. Another problem associated with plantnutrients is that finite recourses are used in the production of mineral fertilizers.
Fungiciders påverkan på kvävehalten i höstvete : hur påverkar användandet av fungicider utnyttjandet och inlagringen av kväve i höstvete?
A common perception is that fungicide treatments increases yield, but that the nitrogen of the particular grain is diluted so that the overall removal of grain nitrogen from the field remains unchanged. The aim of this paper is to demonstrate that a healthy crop reduces the risk of nutrient loss from agricultural land. The results from genotype and plant protection trials often show constant nitrogen content in the grain, although the yield has been increased. Results from such experiments are therefore processed in order to confirm this and show that it is no statistically significant difference between the protein content (and also nitrogen content) in crops which have undergone fungicide treatment compared to crops which remained untreated. The trials processed have been carried out in the southernmost part of Sweden and are distinguished to concern winter wheat production.The explanation to the results is that a healthy crop is able to maintain the biological functions of the plant in a more efficient way than a crop damaged by a fungal infection.
Varför sviktar elevers intresse för matematiki de högre åldrarna? : Vilka faktorer ger elever motivationoch lust att lära matematik?
Drinking water is produced from raw water and is either from groundwater or surface water. This thesis aims to find out if the cleaning process of raw water is sufficiently effective. This is important because consumers are otherwise at risk of waterborne infection caused by pathogens. There are three groups of pathogens; bacteria, virus and parasite. These have different characteristics which mean that they require different water treatment to be separated.