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939 Uppsatser om Plant nutrients - Sida 18 av 63
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).
Småskalig biobränsleeldad kraftvärmeproduktion : teknik och investeringsutrymme
To achieve the requirements to decrease emissions of greenhouse gases by 20 % by 2020, Swedenneeds to increase its use of bioenergy. In doing so it seems natural that those who already haveaccess to large amounts of biofuels in the form of by-products such as straw, wood chips anddigestible materials take advantage of these assets locally. By combining production of heat withpower production at the farm it may be possible to not only reduce the direct use of fossil fuel forheating but also reduce energy costs.The purpose was to simulate different cases of using a small scale biofueled combined heat andpower plant for farm-based systems. A MatLab-model was developed and used to draw conclusionsabout the costs for production of heat and electricity with different conversion technologies.The model uses climate data to simulate the variations in heat energy demand on a day-to-day basis.The given heat demand is the base of the simulation and from this the possible electric output iscalculated. This study has focused on the impact of the following properties: electric-, heat- andtotal efficiency, fuel, fuel price and specific fuel requirements.
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.
Plasmodiophora brassicae ? host and environment interactions
In this thesis, three separate experiments have been performed on different aspects of the interaction between the causal agent of clubroot, Plasmodiophora brassicae, and its hosts.
In the first experiment the pathotype of the P. brassicae single spore isolate, which is currently used to construct a reference genome, has been classified using the ECD bioassay. The disease severity of infected plants was scored according to two different scales and the pathotype was determined according to three previously published guidelines. The results were compared to previous published studies describing the e3 isolate.
The life cycle of P. brassicae is not well understood.
Torkning av flis med restvärme : Metoder för att sänka återledningstemperaturen
The purpose of this study has been to evaluate whether a Low temperature bio-mass dryer could be integrated with the local district heating system in Malå. The aim is to increase the thermal efficiency of the cogeneration plant in Malå, by lowering the temperature of the cooling medium. Another benefit that comes from this is improved combustion efficiency at the power plant, since drying the fuel causes an Increase of the heating value.Simulations has been made in Excel, and with use of linear regression, to find out if it is profitable. Data for this purpose has been supplied by the power company Skellefteåkraft and furthermore SMHI.The result of the Calculations shows that a very efficient bio-mass dryer is needed, if yield of investments should be made possible. An Investment of 4,27 Mkr, in a dryer, could at a such criterium return 60000 kr/year, if the price of the biomass is 190kr/MWh.
Cultivation of Chlorella vulgaris in nutrient solution from greenhouse tomato production : a possibility to reduce nutrient levels and produce commercially interesting metabolites
The idea of using algae in different areas and exploring its possibilities is nothing new. Already in the early 1950s microalgae was explored as a possible food resource because of its high protein content. Lately there has been an increased interest in its potential for industrial use. Wastewater treatment is a possible use of algae since the algae grow well on the nutrients present in the water. This offers the possibility to grow algae for nutrient reduction and use the biomass for energy or animal feed since many alga species has a good nutritional value.
Approximately 800-1000 m3 water is applied per 1000 m2 of greenhouse area during one season in a tomato production.
Risk analysis and a study of risk awareness and risk communication at LEAF Gävle concerning dust explosions
The purpose of this report is to study the risk of dust explosions at the candy manufacturing plant Leaf Sverige in Gävle, Sweden. The risk analysis was conducted with a preliminary hazard analysis, PHA and event trees. The analysis focuses only on the risk posed to employees and material damages at the plant. No third person injuries have been considered. Another purpose of this report is to study risk awareness and risk communication concerning dust explosions.
Tjänligt vatten i kranen - Membranteknik gör det möjligt : En utredning av pilotförsök i Glemmingebro
Nanofiltration is a proper way of preparation of drinking water. The process has a lot in common with reverse osmosis where a semipermeable membrane is used to separate a pure water flow from the remaining water. A pilot plant was used to ensure that nanofiltration is a suitable technology for a specific waterworks station in Glemmingebro, Ystad. The purpose was also to find out if a pH-adjustment is needed for feed water in a possible full scale plant. In this case nanofiltration is used mainly to remove sulphate and calcium since the raw water contains concentrations of these substances which exceed the limits for potable water. It is important to receive a high recovery (RC), otherwise the deliviery of water won?t be high enough.
Ny teknik för kombisådd :
The use of combi-drilling during spring tillage has become very common in southern
Sweden in recent years. Combi-drilling leads to fewer passes on the field and better plant
nutrient utilisation. An example of a combi-drill is the Väderstad Rapid, which is very
widely used in spring tillage in southern Sweden. The Rapid has separate fertiliser and
seed coulters, which means that the draught requirement is relatively high. It thus
requires large, heavy tractors, which compact the soil and are comparatively expensive to
buy and run.
A few years ago the Finnish combi-drill Tume Nova Combi came onto the Swedish
market.
Dokumentation av underhållssimulatorer för utbildning i vardagssäkerhet
At Forsmark nuclear power plant a new course called "education in everyday safety" has been started in an attempt to improve the safety culture. The goal is to spread the of expectations and approach the maintenance management has set, to all employees working at the plants. During the course, theory is mixed with practical tasks to reach a common view how work should be done to achieve safety for the plant and the people that work there.The practical tasks are done inside "maintenance simulators". They are built inside 20 ft containers which contains two dummy pipe systems. On the pipe systems some valves, a flow meter and a pump has been installed.
Samkörning mellan värmepumpar och fjärrvärme : Bostadsrättsföreningen Bogården
This diploma work covers an investigation over the heat - and hot water systems of thetenant-owner's association, Bogården. The heat - and hot water needs of Bogården aresatisfied by both district heating as well as three heat pumps. Implemented investigationshows that the heat pumps are not used in a profitable way. Apart from that, the reservepossibilities are small. There is also a risk of the growth of Legionella bacterium in thehot water system.Since the heat pumps are already installed, HSB-Gävleborg (responsible for Bogården)has a wish to investigate possible proposed actions for optimization of existing plant.After completed investigation, a new proposed action is presented.
Stubbtransporter och bränslekvalitet hos stubbved :
Stump wood is a hot alternative when the heating plants demands more and more forest fuel. The aim with the study has bean to calculate the costs in four different systems for transportations of stump wood, examine if there are any differences in fuel quality for the stump wood in the different systems, analyse if the fuel quality in stump wood is affected with the time it lays by the road side and how much space the stump wood demands on the road side. To calculate the costs for the different systems a system analysis was carried out, where some of the costs were collected through field studies on Holmen Skog stump experiment and other costs were collected from literature and contacts. Data for the fuel quality study was collected from Eons heat plant in Norrköping. Data for the study of how much space stump wood takes along a roadside was collected from field studies.
Platsanalys, grunden för en gestaltningsprocess
Uppsats för avläggande av högskoleexamen i Kulturvård, Trädgårdens hantverk och design 7,5 hp, 2014.
Möjligheten för solceller genom solcellskooperativ och solelbörs
This candidate thesis contains the possibility of expand the Swedish photovoltaic market through photovoltaic cooperatives and a photovoltaic exchange. In the current situation there is a lot of problems with production of electricity from photovoltaic, that?s why we show some possibilities how to avoid these. To understand the problem with photovoltaic produced electricity we first give you a background.We show how to expand the Swedish photovoltaic market by describing how a photovoltaic cooperative and photovoltaic exchange could work in Sweden. It have been confirmed from our market research that the interest of photovoltaic cooperative and exchange is high.To find out how profitable photovoltaic is in Sweden, have three projections been made.
Traditionella växtbaserade läkemedel. : Är Echinacea och Ginkgo terapeutiskt verksamma?
SummaryHerbal remedies have been used for many years to alleviate various symptoms. They were used in ritual acts to reassure the Gods and as medication. Plants as rhubarb and ginseng were used in China long time ago. The Egyptians had knowledge of herbal medicine such as aloe, myrrh and henbane, 1550 BC. The father of medicine Hippocrates used a large number of herbal medicines, and had many theories on the subject.Different parts of the plant can be used to extract the active ingredients.