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336 Uppsatser om Chemical Vapour Deposition - Sida 2 av 23
Kvävestatus och risk för nitrifikation i två avverkade skogsområden i Halland
Nitrogen deposition leads to environmental damage in areas where the nitrogen deposition is high. Southwest Sweden receives an annual nitrogen deposition of up to 20 kg N/ha. Nitrogen that is not assimilated by the vegetation is accumulated in the soil, which may lead to nitrogen saturation and an elevated risk of nitrogen leaching. Nitrogen leaching from forest areas in southern Sweden has proven to be higher than from agricultural areas, which have been thought to be the main contributors to elevated nitrogen levels in rivers and lakes. The amount of nitrogen that leaches depends on the fraction of the total nitrogen in the soil that consists of nitrate, since nitrate is easily transported through the soil.
Implementeringen av REACH : ett led i att bidra till en hållbar utveckling : Fallstudie på ett SME-företag
The importance of chemical use is enormous for areas such as agriculture, industry and medicine and hence a prerequisite for our modern society. In order to protect humans and the environment from the negative effects of chemical use, chemical regulations have been used at a relatively early stage in our history. The purpose of REACH, the new chemical regulation of the European Union, is to generate new knowledge of chemicals within the European market and to increase the responsibilities of the enterprises when it comes to risk management. Whether the enterprises will implement the regulations or not will be of vital importance for the realization of the law?s intentions.The purpose of this study was to identify possibilities and problems that can occur when a downstream-user SME is about to implement REACH.
Surhetstillståndet i bäckar uppströmskalkdoserare i Dalarnas län
The acid deposition of sulphur- and nitrogenoxides from combustion of coal and oil cause acidification that lowers pH and gives increased contents of metals and altered aquatic biodiversity in the stream. The liming of lakes and streams, which was introduced to resist the acidification, demand large economic resourses despite of the decreased deposition of the acidifyng substances. Some of the streams are influenced by the acid deposition, while others are naturally acidic. It is therefore importaint to separate the anthropogenically acidified waters from the naturally acidic, in order to optimize the use of governmental fundings for liming. This thesis aims to estimate the acidity status and impact of acidification on 24 catchments upstream liming dispensers, which is part of the liming activities at the County of Dalarna.The acidity status of the streams was classified according to the Swedish Environmental Protection Agency old classification system (Naturvårdsverket 1999) as very acid to acid, with small ability to withstand a pH-change (alkalinity) due to acid deposition.
Förslag till modell av kemikaliespridning i mark anpassad för användning vid räddningsinsats - Kemspill Mark 4.0
After emergencies involving chemical spills it is of great importance that correct measures are taken with short notice, both for the security of people and in order to minimize future environmental consequences. The RIB-unit at the Swedish Rescue Services Agency initiated this study, the aim of which is to propose changes to the existing chemical transport calculation tool: Chemical Spill 3.4, included in RIB - Integrated Decision Support for Civil Protection, so that it can be used for decision support as well as in preventive work. A rough estimation of chemical transport in the subsurface is considered being of great importance when making decisions during emergency response operations.The proposition presented in this report is a non site specific chemical transport model which is designed to give a rough estimation of NAPL flow in homogenous isotropic soil shortly after an instantaneous release. The model can be used at two levels; both in situations without access to information on subsurface properties, and with more accuracy in situations with knowledge of the included parameters. For that reason the user can choose among predefined alternatives or assign the parameters a numeric value to increase the quality of the model output.
Övervakning vid allmän anestesi och stående ingrepp på häst
The purpose of this literature study was to describe techniques for monitoring general anesthesia and standing chemical restraint in the horse. A number of various techniques and devices related to e.g. blood pressure measurement, blood gas analysis and pulse oximetry are defined, and finally their clinical relevance and reliability are discussed.
The equine patient is generally far more exposed to anesthesia-related risks than other smaller species. Complications such as hypotension and hypercapnia are commonly seen during general anesthesia. Thus, close monitoring is essentially performed by the veterinary nurse, whom is responsible for monitoring the anesthetized patient.
Utfasning av farliga kemikalier - Vid Banverket och Vägverket
Large quantities of chemicals are used in all areas of society. The chemicals can be toxic and dangerous for the environment if used incorrectly. To protect people and the environment from dangerous chemicals, a good control of them and an active work to phase out hazardous substances in all areas where chemicals are present, are needed. Banverket and Vägverket handle in production a wide range of chemical products. Many of the products are dangerous to the environment, for those who work with them and to others who may come into contact with them.
Växthusvävens fukttransmission ? Hur struktur och materialval påverkar växthusvävens fuktgenomsläpplighet
Växthus används för att ge ett bättre odlingsklimat åt grödor och växter. För ytterligare förbättring av förhållandena används växthusvävar som exempelvis kan reglera temperatur, fuktighet och ljustillförsel. Väven som behandlas i denna rapport är en så kallad energiväv som främst har till uppgift att minska energiåtgången vid uppvärmning.När väven är fördragen nattetid, ökar luftfuktigheten då grödorna avger fukt dygnet runt. Fukten kan kondenseras mot energiväven, vilket gör att det bildas droppar på väven som kan falla ned på växtligheten. Den höga luftfuktigheten kan medföra svampsjukdomar och i övrigt också bidra till att tillväxten avstannar.
Åkertistel : biologi och icke-kemisk bekämpning
A growing problem in Swedish herbicide free agriculture, the Canadian thistle has been the object of several new trials, seeking methods for non-chemical weed control. The new trials have mainly confirmed earlier experiences; that the most successful methods of control are springtime ploughing, repeated cutting and competition from a stout crop. Row hoeing has also been proven effective. As opposed to earlier recommendations, half season fallow has shown to be a risky and often ineffective method of control. Trials regarding biological methods have shown that above others thistle rust (Puccinia punctiformis) may have the potential of controlling Canadian thistle the future.
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Avfall på byggarbetsplatsen : statistik som hjälper platschefen
The purpose of this report is to find a model of statistics for construction and demolition waste, which makes it useful for the local manager at the building site. The intention with the model is that it will be used as a support of the local manager, to direct his project towards reduced strain of the environment. The model will also be used to make it easier to control that the claims from authority and aims for the environment are achieved. To familiarise with the subject waste handling within the building and construction sectorI have done a literature search. I have also been studying rules and regulations regarding the waste handling.
Total organic carbon (TOC) and chemical oxygen demand (COD) - Monitoring of organic pollutants in wastewater
Total organic carbon (TOC) and chemical oxygen demand (COD) are two methods used for measuring organic pollutants in wastewater. Both methods are widely used but the COD method results in production of hazardous wastes, including mercury.The purpose of this study was to validate the method TOC that will replace COD and find a factor to convert TOC to COD. In this study 26 samples were analyzed from four sewage treatment plant in the municipality of Enköping.The results show that the COD method could be replaced by the TOC method.The factor for COD/TOC was between 3.1 - 3.3. Both methods will be used in parallel until 2013 when it will be forbidden to use the COD analysis..
Är bor nödvändigt vid skogsgödsling i Sverige?
This thesis has been made on behalf of SCA Skog AB to assess the need of boron in Swedishforest fertilization. Boron has been added to Swedish forest fertilizers since the beginning of the1980s. This makes the fertilizers more expensive and therefore has the necessity of boron inSwedish forest fertilization been raised.The Swedish bedrock generally contains small amounts of boron. The boron in the bedrock istightly bound to the mineral tourmaline and mostly unavailable for plants. This leads to that thecontribution of boron to the soil from weathering is very low besides soils with marinesediments.
Ombyggnation, från sågverkslokal till restaurang. antonio ziakoulis
Pharmaceuticals that are found in marine ecosystems are a threatening environmental concern, which is known to harm both animal and plant life. One of the reasons for this problem is that the waste water treatment techniques are not optimized to clear waste water from its pharmaceuticals contain. In this master thesis four Swedish treatment wetlands were studied, and their ability to reduce numerous pharmaceuticals in waste water. The four treatment wetlands that were studied were those in Oxelösund, Trosa, Nynäshamn and Eskilstuna. Two ecotoxicological tests and chemical analysis were used.
Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier
Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in the event of rainfall. An increased level of radioactivity in the plants may occur due to interception and retention of the radionuclides. If the content of the plants is above the threshold limit value, entire yields may have to be destroyed. In order to prevent contamination or decrease the content countermeasures can be taken. The impact of the
biomass, leaf area index (LAI) and growth stage of the plant on the interception and retention is important to know in order to decide which countermeasures to use.
Weather may also be an important factor.
In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley and spring oil-seed rape was studied.
Conqueror för Indigo
Conqueror for Indigo is production treated with an active chemical to maximize the ink adhesion.ArjoWiggins has found that another chemical, the candidate compound, would improve the propertiesof the paper. ArjoWiggins therefore wish to replace the current compound. To strengthenthe patent requirements for ink adhesion needs to be determined. A theory is developed to whychemicals with certain properties maximize the ink adhesion. Experiments are performed but theresults are inaccurate.
Överföring av radiocesium till potatis vid olika nedfallstidpunkter :
Agricultural land could be polluted by radioactive substances after a fallout. We would then need information about the level of contamination to decide whether the crops could be utilized as food under these circumstances. In an experiment carried out during the 1990ies the retention of 134Cs in potato haulm and the transfer to the tubers were studied. The experiment was carried out during three consecutive years. The plants were cultivated in pots under field conditions and the artificial deposition was sprayed directly onto the potato haulm at different times during the growing season.