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336 Uppsatser om Chemical Vapour Deposition - Sida 20 av 23
Är det möjligt att använda SCR-rening av rökgaserna vid inblandning av avfall i biobränslet?
Waste appears to be a low-cost fuel compared to biofuel. This Masters thesis was conducted for Vattenfall Utveckling AB and deals with how waste in the fuel affects the performance of a SCR-catalyst. Different mechanisms of deactivation were surveyed, focusing on the poisoning mechanism. A literature study was carried out, which was used as a reference when analysing the results.Small samples (9x2x2 cm, 64 pieces) cut out from a full-scale unused honeycomb catalyst were exposed up to 1500h in two different combustion plants, Johannes in Gävle (co-combustion) and Högdalen in Stockholm (waste-combustion). The activity was measured mainly at 300°C but also at 250, 350, 375 and 400°C.
Sustainable business practices : a review of eco-efficiency
The current demanding business environment requires corporations to act fast in finding effective solutions to problems given the myriad of challenges they face (Dyllick & Hockerts, 2001). The challenges include the impact of climate change on business practices, natural resource consumption, chemical pollution, technological change etc. Moreover, the forces of globalization, heightened concerns about the deteriorating quality of the physical environment and increased stakeholder power are also increasingly having a real influence on business practices (Rainey, 2008).
Since 1992, the World Business Council for Sustainable Development (WBCSD) has encouraged the adoption of the concept of ecological efficiency (eco-efficiency) to support business efforts aimed at addressing some of these challenges. The aim of eco-efficiency is to reduce the amount of energy and materials used in production processes to achieve economic and environmental benefits (WBCSD, 2000).
Giraffens blodtrycksreglering
Through previous studies during my education, I have experienced that chemical deicing road salt is a known problem, mainly in southern Sweden. Road salt causes damage to the environment and also damage to vehicles and structures such as bridges, etc. Road salt causes vehicles and steel constructions to rust, leading to increased costs for repairs of damage to structures. Road salt also causes damage to the plants and the economy to suffer, when plant material and soil needs to be replaced. In order to get closer to a solution, I put up three questions.
Dagvattnets föroreningar som potentiellt hot för en god ekologisk och kemisk status i ytvattnet : En kartläggning av Vallentuna tätorts dagvattenhantering utifrån dess tillsynsbehov
The EU's Water Framework Directive aims to a long-term and sustainable use of our water resources and wants to ensure good water quality in Europe's water bodies. Discharge of polluted stormwater into receiving waters can be a threat to their ecological and chemical status. Municipalities are responsible for supervision of the environmental quality standards (EQS) and therefore need to gain knowledge of current stormwater management, the expected level of pollution emissions and possible appropriate purification steps to ensure that the goal of good water quality is achieved.This master thesis aims to provide this knowledge in the example case of Vallentunas urban area and wants to prepare future oversight so that it can be assessed how much the discharge of polluted stormwater into the local receiving water is a threat to its status. With the help of maps, aerial photographs, site observations and individual discussions those areas are mapped where appearance of moderate to highly polluted stormwater could be suspected. The degree of pollution at the discharge points is determined based on land use upstream and uses standard values according to the administrators assistance "Tillsyn av dagvatten" (MSL 2014).The study identifies 100 areas in need of supervision regarding their stormwater management.
Igensättning av långsamfilter i Östby vattenverk i Kramfors : studie av påverkande faktorer
Östby waterworks in the community of Kramfors has since 2003 had problems of fast clogging of the slow sand filters. As the clogging appears more often, they must be cleaned more frequently which has made the drinking water preparation difficult. Wintertime it has sometimes been impossible to clean the filters which has led to their closing and this has influenced the water quality negatively.The waterworks is a surface waterworks which takes its raw water from the lake Sjöbysjön. The water is flocculated and filtered in a contact filter with the flocculent EKOFLOCK 91. Thereafter it is alkalinized before it reaches the outdoors placed slow sand filters.
Grundvattensänkning till följd av järnvägstunnel genom Hallandsås : miljökonsekvenser relaterade till förändrad kväveomsättning i mark
This thesis was carried out to give some background information to a report of SLU (Swedish University of Agricultural Sciences) for the Swedish National Rail Administration (Banverket). The requested information was to provide basic data for an environmental impact assessment of the construction of the tunnel through Hallandsås. The aim with the thesis work was to discuss and quantify the leaching of nitrate and the emission of nitrous oxide from the soil at the groundwater level established through the tunnel project. The nitrogen related processes that could be affected were described and discussed. The different areas where a decreased groundwater level can cause changes in the nitrogen processes are the wet and moist areas.
Improving peri-urban home gardens in Hyderabad, India
Insufficient intake of vegetables is a reason for micronutrient deficiencies and malnutrition in developing countries. With urbanization, globalization and a growing world population it is of major importance to secure sufficient food supply for the world?s population. Part of the solution to increased food security among the world?s poor could be the introduction of vegetable home gardens, plots for small scale vegetable production which can provide households with sufficient vegetables as well as serve as an extra income source.
The study Improving peri-urban home gardens aims at examining the existence of vegetable home gardens in the peri-urban areas of Hyderabad, India.
Små skogliga vattendrag i Värmland - Generell beskrivning, förekomst av traktorspår samt spårens inverkan på bottenfaunan :
Modern forestry requires a high degree of machine traffic for clear felling and scarification operations. The machines most frequently used are big and the traffic often results in tracks on the forest ground. There are many small streams running through a forest, in connection to logging operations, machines might cross these frequently. These crossings could result in the erosion of fine particulate inorganic matter, which ends up in the stream. The aim of this thesis was to give a general description of small forest streams of order-one in the county of Värmland and to determine the frequency of machine tracks in small streams.
?Rätt avlopp på rätt plats? : ? Livscykelanalys av tre enskildaavloppsanläggningar
?Rätt avlopp på rätt plats? ? Livscykelanalys av tre enskilda avloppsanläggningarProblemen med övergödning i Östersjön och i Sveriges insjöar är stort och enskildaavlopp pekas ut som en central aktör, framförallt beträffande fosforutsläppen. I Sverigefinns det ungefär en miljon enskilda avloppssystem och nästan hälften av dessa har enså pass bristande vattenrening att de inte uppfyller gällande lagstiftning. Utvecklingenav nya tekniker för rening av avloppsvatten har länge strävat efter att minska utsläppenav övergödande ämnen, detta ibland på bekostnad av andra utsläpp, så somväxthusgaser och försurande ämnen.Det här examensarbetet har därför med hjälp av metodik från livscykelanalys (LCA)utvärderat tre enskilda avloppssystem med tanke på deras utsläpp av växthusgaser,försurande gaser samt övergödande ämnen. Då misstanke också fanns att de lokalaplatsegenskaperna påverkar de enskilda avloppssystemens totala miljöpåverkan,utfördes även en intervjustudie med ett antal av landets kommuner.
Riskbedömning vid Saltvikens kopparverk
AbstractAt Saltvikens copperindustry, which is located in the municipality of Oskarshamn, copper was refined from sulphiteore some hundred years ago. The ore underwent several steps in the process before the final product was received. These steps all had an influence on the environment through discharge of heavy metals. The area where the copper industry was located is today considered to be of specific national interest due to its valuable nature and cultural values, as well as its value for recreational outdoor activities. Therefore, it is important to determine the present level of contamination and if any transport of contaminants have occurred, and to identify the risks that are associated with the site both at present and in a longer time perspective.Thirtynine soil samples and 16 sediment samples have been analyzed.
Vägsaltets effekter på växter i urban- och offentligmiljö : ett växande problem
Through previous studies during my education, I have experienced that chemical deicing road salt is a known problem, mainly in southern Sweden. Road salt causes damage to the environment and also damage to vehicles and structures such as bridges, etc. Road salt causes vehicles and steel constructions to rust, leading to increased costs for repairs of damage to structures. Road salt also causes damage to the plants and the economy to suffer, when plant material and soil needs to be replaced. In order to get closer to a solution, I put up three questions.
Utveckling i Ammerån : att skapa ett hållbart fiske med hög kvalitet
Ammerån which is a small forest river in eastern Jämtland is a well-known river that has been a popular fishing river for a long time. The actual Ammerån begins downstream the lake Solbergsvattnet at Hammerdal and flows into the Indalsälven 10 km upstream Hammarstrand. The river environment switches between forests with wilderness feeling and open agricultural land. The entire Ammerån is today a nature reserve and protected from hydropower development. Fishing in Ammerån has mainly been focused on trout and grayling, and is so even today.
Evaluation of an ectomycorrhizal macrofungi as an indicator species of high conservation value pine-heath forests in northern Sweden
Since the 1950s, the development of modern rotation forestry in boreal Fennoscandia has resulted in a severe reduction of older forests, and a high degree of fragmentation among the small patches that remains of old forest. In Sweden, when performing conservation value assessments in order to identify and preserve the remaining forest habitats, the government authorities use to a significant extent a set of indicator species that indicate habitats of high biological conservation value. One species considered to indicate high conservation values in pine-heath forests is the red-listed ectomycorrhizal (EM) macrofungi Sarcodon scabrosus (Fr.) P. Karst. In the present study, the validity of using S.
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).
Salmonella prevalence in the poultry feed industry in Pakistan
Abstract
One of the leading causes of food borne infections in the world is due to Salmonella by con-suming poultry products including eggs and meat. According to US Food and Drug Admin-istration (2009), 2 to 4 million cases of Salmonellosis in humans occur every year only in US. Salmonella causes wide range of diseases with enteric and typhoid fever, food poisoning, di-arrhea and gastro-enteritis. Many serotypes of Salmonella do not have host specificity and cause disease in all kinds of animals and humans. Salmonella has capability to modify accord-ing to the changing environment and it can develop resistance against routine elimination practices of sanitation, chemical treatments and antibacterial drugs.
Newly established poultry industries in Pakistan are confronting various infectious diseases including Salmonellosis while in Sweden Salmonella prevalence in animal products con-sumed for humans is extremely low.