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183 Uppsatser om Radiation dose - Sida 4 av 13

Simulering av kabelbränder i sekundära säkerhetssystem med CFD-koden SMAFS

This report contains CFD-simulations of cable tray fires in nuclear power plant applications with the CFD-code SMAFS. Furthermore the report evaluates the use of CFD-codes within this kind of problems. The assessment of this report is that there is a tendency towards the good use of CFD-codes but before using it solely more research has to be done on the subject..

Den finansiella nedgångens påverkan för politikers aktivitet : En studie av LiV

Essay in political science, C-level, by Ronak Bozorgi, fall semester 2007. Tutor:P.O. Norell. ?The affect of financial decline on politician?s activity.

 Solenergi En del i ett långsiktigt, hållbart byggande

The sun is essential to life on earth and no matter where you are, there is a constant need ofenergy. Nearly 800 000 years ago man learned for the first time to use fire in a controlled way.Since then, fire has given us the opportunity to inhabit places despite a cold climate. In Swedenthe resident sector accounts for a major part of the total consumption of energy. In a time whenenvironmental issues and greenhouse effects are increasing, we also see a future of rising energyprices. With this perspective, we have in this bachelor thesis in the Building Environment at theRoyal Institute of Technology, KTH, in Stockholm decided to focus on the renewable energysource, solar energy.The energy from solar radiation is a free resource and does not have any negative effects uponthe environment.

Fördelar och nackdelar med vismutskydd över bröst vid datortomografiundersökning : En litteraturstudie

Sammanfattning Bakgrund Stråldosen vid en datortomografiundersökning (CT-undersökning) kan vara 100 gånger större än vid en konventionell röntgenundersökning [1]. På 10 år har antalet CT-undersökningar nästan fördubblats [2], vilket också innebär att stråldosen till patienterna ökar [1]. Bröstkörtlarna är ett av de mest strålkänsliga organen och är därför viktiga att skydda [3, 4]. Material som dämpar röntgenstrålning kraftigt och som lämpar sig för strålskydd är t.ex. bly och vismut [5].

137Cesium i myrsamhällen i Gävleborgs län 24 årefter Tjernobylolyckan

24 years have passed since the Chernobyl accident when radionuclides were spread over largeareas of Europe, including the Scandinavian countries. Today, measurable activities of 137Csare still observed in many Swedish ecosystems.Ants (belonging to the order Hymenoptera) are social insects which collect organic materialfrom a large area around their nests. This study focuses on the 137Cs activity in ant nests andthe cesium accumulation in these nests. The aims were (1) to estimate the 137Cs fall-out in1986, (2) estimate the radiation exposure of ants and (3) find how 137Cs is distributed in an anthill. Seven ant hills (occupied by the species Formica polyctena) were studied near the villageof Hille, situated north of the city of Gävle in central Sweden.

Smärtlindring i samband med vaccination av fisk :

Vaccination of fish can be assumed to cause pain. This study was designed to see if we can minimize the suffering of fish following vaccination. Fishes are cold-blooded animals and thus more primitive than warm-blooded animals. Despite this, many organs, e.g. the nervous system, have the same basic structure as that of other vertebrates. The fibre system for conducting pain is more diffuse than in humans.

Spermaadhesiner i olika fraktioner av hingstsperma :

Breeding-induced endometritis in horses seems to be down-regulated by certain components in the seminal plasma. These components are most likely some of the proteins in the seminal plasma in the stallion ejaculate, the so-called spermadhesins. This study aimed to recognize these proteins and determine their quantities in different fractions of the ejaculate. Fractionated ejaculates from four stallions were used to determine the presence and amount of proteins by way of size-excluding chromatography. All former known proteins, except two, were recognized in this study.

Does vaccination against Feline Parvovirus protect hospitalized raccoon kits from clinical outbreaks of parvoviral disease?

The Northern Raccoon (Procyon lotor) belongs to the Carnivore-family and is a species endemic to North America. Every year hundreds of orphaned raccoon cubs are admitted into the Wildlife Rehabilitation Center of Minnesota (WRCM), a non-profit organization where all injured or orphaned wild animals are admitted and receive quality health care with the goal of being released out into the wild. The WRCM routinely vaccinate all of the admitted raccoon cubs with a killed feline panleucopenia vaccine, but despite this there are outbreaks of parvovirus infection every year where up to 50% of the admitted cubs have been euthanized or died. The objective of this study was to determine whether vaccinating the admitted raccoon kits has any significant protective effect to developing clinical parvoviral disease. A single-blinded cohort study was designed with two parallel, independent groups. One group was given a dose of killed feline parvovirus vaccine at admission, and the other group was not given any vaccination at all. Assignment to the vaccinated or unvaccinated group was on a per-litter basis and done randomly by drawing lots out of a box.

Hur påverkasogräsuppkomsten av jordbearbetning :

Today it is common to spray against most weeds by using very expensive weed-killers. The goal for every farmer is to have as low costs as possible for their use of machines and weed-killers. Therefore it is in everyones interest to find other methods to fight the weeds. Finding a way to reduce the rise and growth of weeds already at the preparation of the soil would lower the number of laps over the field and also decrease the amount of weed-killing dose. Tests show that by harrow in the dark it is possible to reduce the population of weeds with up to 60%, but the normal reduction would be about 20-30%. To verify the results above we made tests by using two different methods of preparing the soil. We tested ploughing and harrowing in daylight and during night. Later we checked the number of different weeds in areas prepared in daylight and during night. By studying the results from the different methods used we found a considerable reduction of some kinds of weeds in areas prepared during night..

Spolmaskangrepp är ett ökande problem hos värphöns

This literature review summarizes available data on infection with the parasitic roundworm, Ascaridia galli, as a cause of disease in poultry, including the consequences of a conversion to alternative production systems. Ascaridia galli has a direct life cycle with resistant eggs that survive and are easily spread in the environment, especially in systems with bedding materials where the faecal contact is high. The infection is usually subclinical but depending on the infection dose, the symptoms range from weight loss and diarrhea to mortality. Factors such as the feed composition and genetic variation among different hybrids clearly affect the establishment rate of the infection. Ascaridia galli will probably become an increasing problem, with a shift from the traditional battery cages to alternative systems where the risk of re-infection is high.

Brännkammare för träpulver : Teoretisk analys och praktisk försök

The thesis describes a completely new biofuel system to generate particle-free heat from combustion of ash-containing biofuel particles at high temperatures.The suggested system gives opportunities to introduce biofuels in new areas.Main components in the suggested system is a heat radiating combustion chamber intended for pulverized wood, combined with regenerators to extract heat from flue gases and simultaneously preheating the combustion air.The thesis contains a description of the suggested system, theoretical considerations, calculations regarding the combustion, and includes results from tests performed.The results from calculations and tests performed concludes that the system is workable and possible to apply..

Use of oxytocin to improve diagnosis of subclinical mastitis caused by Staphylococcus aureus

Mastitis, inflammation in the udder tissue, caused by S. aureus is a big problem in dairy cattle production. It causes suffering for the cow and curing or replacing the infected cow is costly for the farmer. It is known that beef cattle also suffer from mastitis caused by S. aureus.

Etiologi och patogenes för benign prostatahyperplasi hos hund

This literature review summarizes available data on infection with the parasitic roundworm, Ascaridia galli, as a cause of disease in poultry, including the consequences of a conversion to alternative production systems. Ascaridia galli has a direct life cycle with resistant eggs that survive and are easily spread in the environment, especially in systems with bedding materials where the faecal contact is high. The infection is usually subclinical but depending on the infection dose, the symptoms range from weight loss and diarrhea to mortality. Factors such as the feed composition and genetic variation among different hybrids clearly affect the establishment rate of the infection. Ascaridia galli will probably become an increasing problem, with a shift from the traditional battery cages to alternative systems where the risk of re-infection is high.

Inokulmmängdens betydelse för utveckling av vetets stråbasröta orsakad Fusarium graminearum : utvärdering av ett biotest

Fusarium graminearum is one of the most important pathogens on cereals and causes major crop losses around the world. The most cultivated cereal in Sweden is winter wheat. F. graminearum produces both sexual and asexual spores for dispersal. Multiple factors affect the production of these spores.

Uran i dricksvatten : litteraturstudie om reningsmetoder samt pilotförsök med jonbytesteknik

Uranium (U) is a naturally occurring component in bedrock and under the "right" conditions it can dissolve and move into the ground water. Since many people in Sweden depend on drilled wells as their main drinking water supply, they may be exposed to the uranium in the water. Radioactive radiation is not the major concern associated with naturally occurring uranium. It is rather the chemical properties of uranium that make it a potential danger to human health. Uranium is proven to have toxic effects with respect to the functioning of the kidneys.

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