Seed companies have developed novel weed control technologies to combat herbicide-resistant (HR) weeds based on the use of new genetically-modified (GM) crop cultivars and auxin herbicide formulations. These herbicides can variably affect the growth and yield of susceptible cotton even at low concentrations depending on growth stage at exposure. As such, research was conducted in each of two locations in Mississippi in 2014, 2015, and 2016 to determine the cotton growth stage most susceptible to injury and yield effects from simulated misapplications of sub-lethal 2,4-D or dicamba concentrations. Results indicate that generally a decrease in yield partitioned on lower nodes and inner positions was accompanied by a compensatory increase in yield partitioned on vegetative branches and aborted terminals. However, the magnitude of these yield effects differed based on growth stage at exposure and based on which herbicide was used.

Field studies were conducted to test three application methods for applying antagonistic herbicide combinations: 1) tank mix (TMX), 2) mix-in-line (MIL), and 3) separate boom (SPB). Sethoxydim applied with bentazon, glyphosate applied with dicamba or 2,4-D, and clethodim applied with dicamba or 2,4-D had higher efficacy when applied using the SPB method. Antagonism of all the herbicide combinations above was observed when applied using the TMX and MIL methods. In some cases, antagonism was avoided when using the SPB method. Three application methods tested in greenhouse studies were 1) TMX, 2) synthetic auxin applied first (AAF), and 3) synthetic auxin applied second (AAS). The AAS application method resulted in higher weed control than the TMX and AAF methods. Analysis done through liquid chromatography mass spectrometry supported the greenhouse results with higher rates of glyphosate detected with the AAS method.

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I takt med stigande oljepriser har ett av Sveriges största odlingsföretag Svegro bestämt sig för att byta ut sitt nuvarande värmesystem. Svegro består idag av växthus på ca 50 000 m2 på Thorslunda gård, Färingsö. Uppvärmningen sker idag med hjälp av oljeeldning samt den värmeenergi som omvandlas från växthuslampor. Det nya värmesystemet kommer att använda sig av ett annat förbränningsalternativ än mineralolja. Detta kommer göra det möjligt för Svegro att sänka sina energikostnader och minska miljöpåverkan genom reducerat koldioxidutsläpp. Kraven som ställs är att det nya värmesystemet ska kunna integreras med det befintliga värmesystemet och samtidigt leva upp till dagens ekologiska krav. Målet med bytet av värmesystem är att sänka energiförsörjningskostnaderna men också att klara av framtida högre ställda krav och miljömålsättningar. För att avgränsa rapporten har tre olika förbränningsalternativ behandlats där alla passar bra med den nuvarande vattenburna värmelösningen. Alternativen består av bioolja, pellets och flis. För att bestämma det bästa alternativet har en jämförelsestudie mellan de olika bränslena gjorts där faktorer som investeringskostnader, miljöpåverkan och bränsleeffektivitet beaktats. Utifrån analyserna av resultaten i rapporten föreslås pellets som det bäst lämpade systemet för Svegros anläggning. Enligt livskostnadsanalysen i rapporten kommer det nya systemet att ha betalat av sig efter 1,5 år och efter det kommer besparingar på ca 5,5 miljoner kr göras per år jämfört med om det befintliga systemet skulle bevaras. Det nya bränslet kommer utöver ekonomiska besparingar även minska CO2-utsläppen med ca 2300 ton per år. Konsekvenserna av att välja pellets som förbränningsalternativ är att man måste kombinera pelletsförbränningen med en biooljeuppvärmning, detta för att växterna ska klara av att överleva extremt kalla vinterdagarna. / While the oil price continues to increase, one of Sweden’s largest indoor growing companies Svegro has decided to replace their existing heating system. Svegro is a large green house with an area of approximately 50 000 m2 and is located at Thorslunda gård, Färingsö.The heating system today uses mineral oil and the heat from assimilation lamps. The new system will be using an alternative combustion fuel to the expensive mineral oil. This will make it possible for Svegro to lower their energy costs and reduce their environmental effect by lowering the emissions of carbon oxide.The requirements are that the new heating system should be able to be integrated with the already existing system and at the same time live up to today´s ecological requirements. The goal of replacing the heating system is to reduce the energy costs but also to manage future demands and environmental ambitions. In order to define some limitations for the reports we have chosen three different combustion options where all alternatives fit with the present heating distribution. The combustion options are biological oil, wood pellets and wood chips. To determine the best option a comparison between the different fuels has been done considering factors such as investment costs, environmental impact and fuel efficiency.Based on the analyzed results we suggest that wood pellets will be the most suitable fuel for Svegros facility and heating system. According to the lifecycle cost the new system will have paid off itself after 1,5 years. The savings made each year from changing fuel will be approximately 5,5 million SEK per year compared if the oil still was used. The new fuel will in addition to the financial savings also reduce the carbon dioxide emissions by 2300 tons per year.The consequence of choosing wood pellets as combustion fuel is that you have to combine the pellet burning with biofuel combustion. The combination will make it possible for the plants to survive extremely cold weather conditions during the winter.

The bubble flow is used for different application in steel production and refining processes. It plays in indispensable role in the ladle refining process such as for homogenization and inclusion removal. Hence, it is important to understand the effect of the nozzle outlet geometry on the bubble formation. Three different nozzles with different outlet geometries were examined using a physical model. These geometries were: a) Circle, b) Square with round edges and c) Elliptical. All three nozzles had the same nozzle design and similar outlet cross-section areas. Therefore, the only tested parameter was the outlet geometry. The physical model is a water/air model, that consist of water tank ,the nozzles, gas gauge and a high speed camera. Each nozzle was tested under five different gas flow rates: starting from 10 L/min of air gas flow rate, until a 30 L/min of gas flow rate by incriminating with 5 L/min per experimental trial. Therefore, each nozzle was studied using a 5 experimental sets, so in total 15 experiments were made. For each set, 3000 photos were captured by the high speed camera. The photos were then analyzed using mainly the ImageJ software and the naked eye. After analyzing the photos for the experimental sets the following were found: a) The frequency of bubble formation was for the most part constant with an average of 11 bubbles per second. b) The elliptical nozzle produced for the most part the largest bubbles, while the circular produced the smallest ones. The square nozzle had similar bubble sizes comparable to the elliptical nozzle. c) The circular nozzle resulted in the bubbles with most stable surface, while the elliptical nozzle had the most unstable bubble boundary. The study had a drawback, which is the presence of a jetting flow which reduced the accuracy of the results. Thus, it is recommend that future work can solve this issue by finding at which gas flow rate pure bubbling flow stops for each nozzle geometry. / Bubbelinjektion används för olika tillämpningar inom stålproduktion och raffineringsprocesser. Det spelar en oumbärlig roll i raffineringsprocesser som homogenisering och borttagning av inneslutningar. Därför är det viktigt att förstå effekten av utloppsgeometrin hos munstycket på bubbelbildningen. Tre olika munstycken med olika utloppsgeometrier undersöktes med hjälp av en fysisk modell. Dessa geometrier är: a) Cirkel, b) Fyrkantig med rundade kanter och c) Elliptisk. Alla tre munstyckena har samma munstycksdesign och liknande utloppstvärsnittsarea. Därför är den enda parametern som testas utloppsgeometrin. Den fysiska modellen bestod av en vattentank, munstyckena där var och en undersöks separat, en gasmätare, en höghastighetskamera och modellen använde vatten/luft. Varje munstycke testades under fem olika gasflöden: startande från 10 L/min luftgasflöde, tills 30 L/min gasflöde stegvis 5 L/min per experimentuppsättning. Därför har varje munstycke 5 experimentuppsättningar, så totalt 15 experiment togs. För varje uppsättning togs 3000 bilder med höghastighetskameran. Bilderna analyserades sedan med främst ImageJ-programvara och blotta ögat. Efter att ha analyserat bilderna från experimenten så visade resultaten följande: a) Frekvensen av bubbelbildning var mestadels konstant med ett genomsnitt på 11 bubblor per sekund. b) Det elliptiska munstycket producerade mestadels de största bubblorna, medan det cirkulära producerade de minsta bubblorna. Det fyrkantiga munstycket resulterade i en liknande bubbelstorlek som det elliptiska munstycket. c) Det cirkulära munstycket resulterade i bubblorna med den mest stabila ytan, medan det elliptiska munstycket hade den mest instabila bubbelgränsen. Studien hade en nackdel, vilket är närvaron av ett jetflöde som minskade noggrannheten i resultatet. Det rekommenderas att framtida arbete kan lösa detta problem genom att hitta vid vilken gasflödeshastighet rent bubblande flöde stoppar för varje munstycke

The topic of chemical oxidative degradation in rotational molded polyethylene (high-density cross-linked) chemical (sodium hypochlorite) storage tanks is an industry problem that ranks at the top of current business issues for manufacturers of chemical storage tanks. The degradation of these tanks not only compromises the physical and mechanical properties of the tank material, but reduces the life expectancy of the tank, eventually resulting in catastrophic tank failure. Premature tank failure comes at a hefty cost. The reputation of the manufacturer is questioned often resulting in immediate loss of customer satisfaction and future business. The leaking of the chemical from the failed tank serves as a liable environmental hazard that jeopardizes the safety and welfare of its surroundings – people and environment. And the associated manufacturer of the failed tank is almost certainly responsible for the repair or replacement of the tank. All these associated problems and many more related to chemical tank failure cost this relatively small industry millions of dollars annually. The need to determine the failure mechanisms of these tanks is critically important. Such an understanding will provide industry with useful knowledge that will open the door for improvements in tank performance. There is no question that a deeper understanding of failure mechanisms will improve a tank manufacturer's reputation, increase business sales, and assure environmental safety. The addition of this knowledge will also instill consumer confidence in an industry that is considered to lack refined manufacturing processes and proven quality controls. Such advancements are keys to making rotational molding a cutting-edge, technology-driven process that prepares industry for future growth and development. The purpose of this research is to provide tested empirical data and proven expert analysis that can be utilized by companies in understanding the failure mechanisms of these tanks. The information regarding this topic was collected from various tank samples taken from Poly Processing, a leading manufacturer of rotationally molded polyethylene chemical storage tanks and producer of the examined samples, and Odyssey Manufacturing, a manufacturer of bulk sodium hypochlorite and the end user of the examined samples. In the final chapter of this research, a summary is presented of the important findings regarding the purpose of the thesis study.

Recent events regarding energy policies throughout the globe and advances in technology are making offshore wind farms become a reality. Most offshore wind farms are still, however, built close to land masses, and need to be rigidly attached to the seabed in one way or another. In many countries, both public and private entities are developing new concepts of floating platforms to overcome the thirty to thirty-five-metre depth limit. Some of these new platforms use and adapt previous Oil and Gas platform concepts, while others are built up from scratch. This Master Thesis covers a hydrodynamic and structural analysis of a new concrete floating platform concept developed for medium to deep waters. This work is based on data from experimental model-scale tests performed in a wave tank and from numerical models using linear potential theory, limited here only to regular wave trains. The study focused on the behavior of the heave plates attached to the platform: test data was analyzed in order to find indicators of the largest dynamic pressures on the plates when only motion data was available, and the structural behavior of the plates was studied under different static pressure distributions using a commercial Finite Element Method software. The results from these analyses show that the normal accelerations of the plates -assumed rigid- strongly correlate with the dynamic pressures measured; and that the general structural behavior of the plate, in terms of deformations and bending moments, is well captured when the hydrodynamic load distribution is simplified into a uniformly distributed load of the same magnitude. The results obtained will help reduce the computational effort currently needed in the design of these floating structures, especially at some stages, when numerous scenarios, load cases and combinations need to be studied.

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There is a need in exploring structural health monitoring technologies for the composite structures particularly aged Composite Overwrapped Pressure Vessels (COPVs) for the current and future implementation of COPVs for space missions. In this study, the research was conducted in collaboration with NASA Kennedy Space Center and also NASA Marshall Space and Flight Center engineers. COPVs have been used to store inert gases like helium (for propulsion) and nitrogen (for life support) under varying degrees of pressure onboard the orbiter since the beginning of the Space Shuttle Program. After the Columbia accident, the COPVs were re-examined and different studies (e.g. Laser profilometry inspection, NDE utilizing Raman Spectroscopy) have been conducted and can be found in the literature. To explore some of the unique in-house developed hardware and algorithms for monitoring COPVs, this project is carried out with the following general objectives: 1) Investigate the obtaining indices/features related to the performance and/or condition of pressure vessels 2) Explore different sensing technologies and Structural Health Monitoring (SHM) systems 3) Explore different types of data analysis methodologies to detect damage with particular emphasis on statistical analysis, cross-correlation analysis and Auto Regressive model with eXogeneous input (ARX) models 4) Compare differences in various types of pressure vessels First an introduction to theoretical pressure vessels, which are used to compare to actual test specimens, is presented. Next, a background review of the test specimens including their applications and importance is discussed. Subsequently, a review of related SHM applications to this study is presented. The theoretical background of the data analysis methodologies used to detect damage in this study are provided and these methodologies are applied in the laboratory using Composite Overwrapped Pressure Vessels (COPVs) to determine the effectiveness of these techniques. Next another study on the Air Force Research Laboratory (AFRL) Tank that is carried out in collaboration with NASA KSC and NASA MSFC is presented with preliminary results. Finally the results and interpretations of both studies are summarized and discussed.

Today, the world faces an energy source transformation that is difficult to grasp. To convert to a green energy society, carbon, oil, and natural gas must faze out as fuels during the upcoming decades. Hydrogen gas has received a lot of attention in recent years regarding the challenges in the energy sector, not only because of its multifunctionality as a fuel but also because it is a great energy carrier. The largest part of the green hydrogen gas produced in the future will be made in locations with great possibilities to produce hydrogen gas from solar energy. This means that a huge amount of this will need to be transported (and stored correctly during transportation) to countries with an increased industrial need for hydrogen but with insufficient production of hydrogen. The report will cover two different ways of transporting hydrogen gas. The first one is intermodal transport of tubes (hydrogen gas) or tanks (cryogenic hydrogen), and the second one is through pipelines. The report will also investigate two different ways of storing hydrogen, as a cryogenic liquid or as a compressed gas. The report will also investigate the production of intermodal commodities for compressed hydrogen gas where a material selection will be made to optimise the possibilities to store and transport hydrogen gas. The material selection analysis showed that a duplex stainless steel was the best material for hydrogen gas tubes. From the result, it is clear that compressed hydrogen gas in tube containers is the cheapest transport method with respect to both Operational Expenses (OpEx) and Capital Investment Expenses (CapEx). / Idag står världen inför en energiomställning med stora hinder. För att ställa om till ett samhälle med grön energi står det klart att kol, olja och naturgas måste fasas ut som bränslen under de kommande decennierna. Vätgas har fått mycket uppmärksamhet under de senaste åren när det gäller utmaningarna inom energisektorn, inte bara på grund av dess multifunktionalitet som bränsle utan också för att det är en utmärkt energibärare. Den största delen av den gröna vätgas som produceras i framtiden kommer att tillverkas på platser med stora möjligheter att producera vätgas från solenergi. Detta innebär att en enorm mängd av detta kommer att behöva transporteras (och lagras korrekt under transporten) till länder med ett ökat industriellt behov av vätgas men med otillräcklig produktion av vätgas. Rapporten kommer att omfatta två olika sätt att transportera vätgas. Det första är intermodal transport av tuber (vätgas) eller tankar (kryogen vätgas), och det andra är genom rörledningar. Rapporten kommer också att undersöka två olika sätt att lagra vätgas, som en kryogen vätska eller som en komprimerad gas. Rapporten kommer också att undersöka produktionen av intermodala råvaror för komprimerad vätgas där ett materialval kommer att göras för att optimera möjligheterna att lagra och transportera vätgas. Materialvalsanalysen visade att duplex rostfritt stål var det bästa materialet för vätgastuber. Av resultatet framgår det tydligt att komprimerad vätgas i rörbehållare är den billigaste transportmetoden med avseende på både Operational Expenses (OpEx) och Capital Investment Expenses (CapEx).