
Sökresultat:
2837 Uppsatser om Water activity - Sida 3 av 190
Förslag till placering av anläggningar för att förbättra vattenkvalitén i Tidan
Considering water quality, landuse and reducion of wetland area in the watershed of Tidan, areas witch are in need of constructions to improve the water quality are identified. Constructions are suggested to be located within the smaller streams in the watershed, so that the water is treated before it reaches the stream Tidan..
Deaktivering av metanisering katalysatorer
A titania-supported nickel catalyst was prepared and tested in methanation in order to evaluate its catalytic properties (activity, selectivity and specially, activity loss), and compare it with an alumina-supported nickel catalyst.The titania-supported catalyst did not only show higher stability than alumina, but also presented a different cause of deactivation, carbon formation. In addition, a kinetic model was obtained for the titania-supported catalyst, and a study of the effect of different operating conditions (temperature, composition and partial pressures of synthesis gas and water) on the deactivation rate and carbon formation of this catalyst was performed.
Öppen dagvattenhantering i urbana miljöer :
Storm water causes a number of problems in our country, particularly in city environment with its surfaces of non-absorbing ground materials. At heavy rain falls there are floods due to lack of capacity in the drain system when meeting heavy water masses over a short time. When the drain system is overloaded huge water masses reach the recipient untreated and there causing disturbances in the aquatic ecosystem. Due to emissions from mainly traffic, industries and other human activities the storm water is polluted. Earlier the problem used to be solved technically, by increasing the capacity of the tubes and by construction of reservoirs to delay the floods peaks.
Milk production in dairy cows and goats : a case study in the Nyando district inSouth-Western Kenya
Water is an essential factor for both people and animals, and access to water is therefore of great importance. The water access also largely determines the availability of food for people and feed for animals. The aim of this study was to survey the affect of water access on milk production from dairy animals. The study included nineteen farm visits that were made in the Nyando district in Kenya between February and Mars 2011. Farm visits included interviews with questions about for example number of dairy animals, milk production, water access, feed and water routines.
Smak och konsistens hos ost : en litteraturstudie kring årstiderna och fodrets inverkan
To enjoy the richness of the grazing cows and high yield during the summers, even during the winter, cheese has been the way to store milk for thousands of years. Nowadays yield is high all year around and the cheese production is possible during all seasons. The aim of this paper
is to investi-gate how and why the seasons influence taste and texture of pressed and ripened cheese. Milk is composed of proteins, fat, lactose and water but contains also a lot of vitamins. The quality of milk is very important for the final constitution of cheese.
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.
Vem för de törstigas talan? : En studie av debatten kring vattensektorn
1.1 billion people are today living without sustainable access to improved water. The debate over the water sector has been dominated by the discussion over whether public or private actors are the most competent to manage it. In this paper the arguments pro and contra the two positions are presented to try to overview the debate and to try to find new ways to approach the question of the people living without clean water. By examining possible alternatives towards the discussion of public and private actors, it might result in some new approaches on how to move closer towards a solution. One alternative is local, small- scale projects which focus on the situation of the targetgroup in most need.
Riskbaserat provtagningsprogram för mikroorganismer i Gäddviks vattentäkt
Risk-based sampling program of microorganisms in the water source in northern SwedenAfter several disease outbreaks caused by parasites in the drinking water during the last years, it is more essential than ever to insure that the water supply companies have enough barriers to counteract the presence of microorganisms in the outgoing water. It is also discussed whether climate changes such as increased precipitation can have a connection to the increased cases of parasites in water sources. The water source at Gäddvik is Luleå municipality?s largest and provides drinking water to 64 500 of Luleå?s 74 000 inhabitants. The investigation of microorganisms in the water source, especially in the Lule River has not been as prioritized as the sampling of chemical parameters.
Lakningsförsök med furubarksflis : en utredning om utsläpp av fenolföreningar samt metallsorption
The filters used today to purify water are often expensive and the need to find new filter materials is substantial. Studies of pine bark have shown that this is a material that may be used as an alternative to conventional filter materials, such as activated carbon. However, the study of pine bark has shown that a leakage of phenolic compounds may occur when using the material for water purification. Therefore, the purpose of this report is to investigate the release of phenols from pine bark, in order to evaluate the use of pine bark as a filter material. Another assignment is to investigate the amount of metals adsorbed by the filter material.
Hur mycket "mjölk" ska det vara i mjölken, och hur styr vi det?
In most countries, the dairy industry focuses on the volume of milk produced instead of its composition. This results in a high content of water and a lower proportion of fat and protein. A high proportion of water is not desirable when processing the milk into various dairy products like cheese, cream and milk powder. High water content also increases the costs for transport and storage, and also an unnecessary, albeit marginal, strains on the world?s water reservoir.
Habitatpreferenser hos tjockskalig målarmussla (Unio crassus) med avseende på vattendjup och beskuggning.
The thick-shelled river mussel (Unio crassus) is a red listed species classified as Endangered (EN) and is also considered within the Habitats Directive. The distribution in Sweden is fragmented and it is mostly occurring in the south eastern parts. We investigated the presence of Unio crassus in a section of the stream Storån, Östergötland County, from Falerum to the inflow into Lake Åkervristen. The environmental parameters investigated were water depth, bottom substrate, shading, water velocity and the slope over the water surface. In this thesis I have focused mainly on water depth and shading, comparing sites with and without mussels.
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.
Utveckling av en ytmonterad fördelningsmätare som underlag för individuell debitering av vattenförbrukning i fastigheter
The master thesis, conducted at Metrima AB, concerns the development of a non-intrusivedistribution meter as a basis for individual tap water billing in apartments.The project is conducted in response to the market interest in individual tap water billing inapartments as an answer to environmental concerns regarding water consumption. Due to thehigh installation cost of traditional water meters, a new method of determining waterconsumption, without having to cut water pipes, is proposed.The proposed method distributes the total water consumption for an apartment complex toindividual apartments according to distribution meters, measuring water run-time, in eachapartment. The water run-time is estimated by measuring the water pipe?s outward vibrationsand temperature changes.A test environment was established and a prototype built, using a tilt- and vibration sensor forvibration sensing and a precision temperature sensor to measure temperature changes. As bothsensors work well in the test environment, further testing was done in 3 apartments for aduration of 5 days.
Rationell riskanalys inom VA-verksamhet med avseende på säkerhet, hälsa, miljö och kvalitet
This master thesis is developed based on the desire of the water and sewage department in the municipality of Karlskrona. The department, which vouches for the quality of produced drinking water and sewage cleaning, was in need of help dealing with risk analysis.The water and sewage department is obliged to identify and assess risks according to Swedish legislation. However, no guides for this purpose regarding safety, health, environment and quality were available. The aim of this report was to accomplish a guideline for the performance of risk analysis within water and sewage plants. If the guideline is used, the requirements in the legislation will be obtained.
Förskolebarns motoriska utveckling : -Hur en förskolegård bör utformas för bästa tänkbara utveckling av barns motorik
The purpose of this study was to interview different groups of people (preschool teatcher, parents and theire childen) involved in preschool about their view on outdoor activity and children´s motoric development, and how a preschool yard should be designed to promote childrens development.All parties regard outdoor activity as very important for the development of children. They also think that the outdoor environment today is good but that it could be improved by including some trees and hills. The yard should also contain soil, sand, clay and water. The children prefer grass on the ground over other substrates. This study also gives good indications to decision makers how to build new or to reconstruct pre-school yards in the future..