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80 Uppsatser om Magnesium oxide - Sida 1 av 6

Magnesium chloride in dry cow silage to prevent hypocalcaemia

Milk fever, or parturient paresis, is the second most common disease in Swedish dairy cows. The disorder is associated with the onset of lactation when some cows are unable to meet the metabolic demands of calcium to support milk production and therefore develop a state of hypocalcaemia. Clinical hypocalcaemia (milk fever) may lead to coma and death in severe cases but subclinical hypocalcaemia has also been shown to have negative effects on e.g. feed intake and production and to increase the susceptibility of the cow to develop secondary diseases. The nutritional strategy applied precalving is of great importance in preventing milk fever and e.g.

Magnesiumstatus hos mjölkkor : en fältstudie

Magnesium is an essential mineral that is important for several physiologic and biochemical processes in the body. Deficiency of magnesium is mainly associated with grass tetany, but can also appear in cows during the indoor period. Since long it is known that potassium has a negative effect on the absorption of magnesium. Due to the fact that potassium fertilisation leads to a higher potassium content in forage, it is of interest to study interactions of potassium on the magnesium balance in dairy cows. There are few studies about magnesium feeding to dairy cows in Sweden and the purpose of this study was to investigate how much magnesium and from which feed-sources dairy cows in Sweden get their magnesium. Data was collected from seven farms in the northern part of Uppland and from seven farms in Skaraborg in Sweden.

Effekter av högt kaliumintag på magnesiumbalansen hos mjölkkor :

Magnesium is one of the most important minerals in the body and it participates in many essential processes, such as energy metabolism and protein synthezis. Magnesium deficiency in cattle may occur when they are let out for pasture in the spring, and is associated with tetany, known as grass staggers. A high yielding dairy cow often loses more magnesium daily in the milk than she has available in the body, and magnesium thereby needs to be provided in the feed to prevent the cow from being affected by deficiency symptoms. The uptake of magnesium is mainly located to the rumen and is not regulated by hormones. The surplus is excreted in the urine by the kidneys.

Kalciums och magnesiums inverkan på arsenikavdrivningen i virvelbäddsugnen : The influence of calcium and magnesium on the expellation of arsenic in the fluidized bed furnace

In the fluidized bed furnace at Rönnskärsverken, Skelleftehamn, sulphur-containing ore concentrates are roasted in order to remove about 50% of the sulphur in the incoming ore concentrate. This occurs in order to reach the goal of a matte containing 55% of copper in the following smelting process. At the same time as the ore concentrate is partially roasted pollutions as arsenic, antimony and bismuth are expelled. Earlier made thermodynamic calculations of equilibrium suggested that calcium and magnesium form stable compounds with arsenic and thereby inhibit expellation of arsenic in the fluidized bed furnace, an element that is undesired. The purpose of this thesis work was to gain knowledge of the mechanisms behind the formation of these stable arsenic compounds.

REE-förande fosfater i Blötbergets apatitjärnmalm

The Blötberget deposit is situated in the north-western part of Bergslagen. The mineralization is an apatite-iron oxide ore of Kiruna type. In Bergslagen the apatite-iron oxide ores occur along a zone from Grängesberg through Blötberget to Idkerberget in the northeast and they represent the largest and the most important iron oxide deposit in Sweden, south of Norrbotten.Different REE hosting phosphate phases has been studied by optical microscopy and analyzed by EDS attached to an electron microscope.The key minerals other than iron oxides are apatite, monazite and xenotime. The relative concentration of the REE-bearing phases differs from the other apatite-iron oxide mineralizations in the area, for example Grängesberg, by a higher concentration of xenotime and lower contents of allanite..

Magnesiumintagets betydelse för blodtryck och magnesiumkoncentrationen i stickprov av urin, träck och blodplasma hos häst

The purpose of this trial was to evaluate the possibility to use sampling of faeces, urine and plasma, and measurements of blood pressure as methods of discovering hypomagnesemia in horses, as well as the application handiness of these methods. The most commonly used method of checking the magnesium status of a horse is to analyze samples of serum or plasma. The trial was of a switch-back design, in which the horses were used as their own controls. The animal material was five Swedish warm blooded trotters between six to ten years old, and weighing between 485-620 kg. The trial consisted of three periods that were two months each.

Avgång av lustgas från luftningsprocessen på Käppalaverket

The requirements for wastewater treatment plants (WWTP) are gradually increasing, partly because of higher incoming loads, which in turn require a more efficient treatment process. In parallel with environmental and economic goals there are also desires to lower energy consumption without compromising the wastewater treatment. Furthermore, there is a demand on WWTP´s to alter eutrophication in aquatic systems through better nitrogen and phosphorus removal. An increasing number of WWTP´s have acquired biological nitrogen and phos-phorus removal. A by-product of this type of biological treatment is the formation of nitrous oxide, which is a potent greenhouse gas.

Pulsed inhaled Nitric Oxide - a possible way to treat hypoxemia in colic horses during abdominal surgery

The aim of the present study was to evaluate if pulsed inhaled nitric oxide (PiNO) could be used as a treatment for hypoxemia during general anaesthesia in colic horses. Previous studies have shown a positive response in horses receiving PiNO in comparison to controls, but these studies have only included healthy individuals. A total of 30 horses were included in this present study, they all underwent abdominal surgery because of acute colic that could not be medically treated. Fifteen of the horses received PiNO and 15 horses served as a control group. Arterial oxygenation was improved in all horses receiving PiNO.

Protesutveckling

This report investigates the possibility of developing a new and improved hip prosthesis. The result were five different materials that could be used for the prosthesis. These five solutions were Silicone Nitrate on Cobolt Chrome, phase stabilized Zirconium Oxide on Cobolt Chrome, Silicone Nitrate on Silicone Nitrate, DLC coated phase stabilized Zirconium Oxide and Chromium nitride coated Cobolt Chrome on Cobolt Chrome. In addition to this it was also investigated how to best market the prosthesis and how to transport them from production sites to hospitals..

Syrgasdelignifiering av magnesiumbaserad sulfitmassa med magnesiumbaserad alkali

Syftet med arbetet var att undersöka hur olika reaktionsbetingelser skulle påverka syrgasdelignifieringen av en sur sulfitmassa. De betingelser som undersöktes var utbyte, slut-pH, viskositet och kappatal. Massan som användes kom från Nordic Paper Seffle och alkalit som användes var magnesiumoxid. Syrgasdelignifiering av massan gjordes  i autoklaver i ett PEG bad där tid, temperatur och alkalisatser varierades.Resultaten visar att alla utbyten låg mellan 90-97% och att även de mest aggressiva betingelserna bara gav en viskositets reduktion på 260 enheter, motsvarande 19% av den totala viskositeten.Slut-pH för syrgasavluten hamnade mellan 6,5-9,4 beroende på alkalimängd och temperatur under delignifieringen. Slut-pH minskade när mängden alkali hölls konstant men temperaturen varierades mellan 110-140°C.Kappatalet för massan kunde effektivt reduceras från ett startvärde på 23,4 till ett slutvärde på under 5 med en temperatur på 140°C, alkalisats på 10 kg/ODT och en tid på två timmar utan större förluster av vare sig viskositet eller utbyte.En ovanligt resultat som upptäcktes under arbetet var att delignifieringen tappade i effektivitet med ökad alkalimängd och detta samband gällde vid alla betingelser.En teori om detta kan vara att jonstyrkan i lösningen gör att fibrerna i massan drar ihop sig och att syrgasen får svårare att reagera med ligninet..

Mikroskopering av opaka faser - en studie från Skyttgruvan, Falun.

In nature there are about 4,500 minerals identified. These can roughly be divided into two groups, opaque phases and non-opaque phases, with the exception that some opaque phases also may act as a non-opaque phase in different circumstances. The division is made on the basis of the optical properties. Opaque phases are nontransparent, which means that a different type of microscope must be used. A conventional microscope uses transmitted light while the microscope for opaque phases or the ore microscope uses reflected light.

Formsprutningsverktyg i magnesium

Med hjälp av en stor mängd vindobservationer i tid och rum analyseras vindhastigheters statistiska egenskaper. Det visar sig att weibullfördelningen väl beskriver vinden, bådeårs- och månadsvis. Vidare används variogram för att undersöka vindens korrelation i rummet. En parametrisk variogrammodell som ger en bra beskrivning för närliggandepunkter ärWhittle. Dessutom skattas medelvärdesfunktioner för vindens tidsserier.

Tillsats av biokol till en svensk sandjord : effekter på lustgasavgång, kväveretention och andel vattenfyllda porer

In a column experiment the effect of three different biochars on nitrous gas emissions, nitrogenretention and water filled pore space (WFPS) were studied in a Swedish sandy soil, classified as aCryopsamment. Ammonium retention was positively correlated, while KCl-extractable ammoniumwas negatively correlated, with the specific area of the biochars. The question was raised whether thenegative correlation between extractable ammonium and biochar specific area reflects the amount ofammonium present in the soil or its extractability from the biochar, and whether methods forextracting soil mineral nitrogen, like KCl-extractions, have to be modified for application on biocharamended soils. There was a tendency of increased nitrate retention and KCl-extractable nitrate withbiochar and KCl-extractable nitrate was positively correlated with the specific area of the biochar. pHwas higher for all biochars compared with control, although the differences were not significant, andWFPS was lowered by biochar addition, significantly in one case.

Skrubberavfall : Hantering i hamn

This paper deals with challenges associated with handling scrubber waste in the port of Karlshamn and what various industry partners are doing to meet this growing demand. The main challenges have been the proportion of ships with scrubber, the amount of generated waste and waste characterisation. An understanding of these factors has been crucial in order to ascertain the aim of this study, which has been made with calculations based on leading manufacturer?s scrubber analyses and with an estimation of the quantity of ships with scrubber by examining AIS data from the Port of Karlshamn. In order to calculate the quantity of scrubber waste two different scenarios were established, which in turn produced two different outcomes.

Mineraliseringar utmed REE-linjen i sydvästra Bergslagen

This paper briefly summarizes Bergslagen as a bedrock province in order to give background to the genesis and presence of REE-bearing minerals (short for Rare Earth Elements) in the region. These mineralizations mainly occur along the REE-line, a line aproximately a hundred kilometers in length between Norberg in the north and Nora in the south with a width of a few kilometers. Situated in the southwest of Bergslagen it is currently one of only a few places in Sweden where REE-bearing iron oxide mineralizations are potentially economically viable for mining. Ore microscopy has been conducted in order to characterize an ore sample from Myrbacksfältet, one of few sulphide rich iron oxide mineralizations within the REE-line. Additionally, an electron microscope analysis of a sample from Stålklockan, a suspected REE-bearing mineralization also within the REE-line was confirmed by EDS (short for Energy Dispersive Spectrum) analysis.

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