Field studies were established in 2015 at Bowling Green and Lexington, KY to evaluate industrial hemp (Cannabis sativa) tolerance to various herbicides. Hemp was planted into conventionally tilled soils in mid to late June at a seeding rate of 39 kg/ha in Bowling Green and 22 kg/ha in Lexington. Five herbicide active ingredients were applied preemergence (PRE) the day of planting and six postemergence (POST) treatments were applied to 30 cm hemp with a CO2-backpack sprayer delivering 140 L/ha. Plots were 3.1 m wide by 6.1 m long and were sprayed with a 2.1 m boom sprayer leaving a 0.46 m visual check on either side of the sprayed area. A weed free check and a non-treated control were included and all treatments were replicated four times in a randomized complete block design. Hemp phytotoxicity was evaluated at 14 days after treatment for both PREs and POSTs. Hemp above-ground biomass, weed above-ground biomass, and seed yield were also evaluated. PRE herbicides did not injure hemp as much as POST herbicides, especially at the Bowling Green location. Mesotrione was the most injurious PRE evaluated (> 90%) while bromoxynil and MSMA applications resulted in low phytotoxicity (< 15%). Above-ground biomass was higher in the PRE treated plots, with the exceptions of bromoxynil and MSMA. Weed above-ground biomass was higher in the POST treated plots with the exception of mesotrione. At Bowling Green, PRE herbicides resulted in comparable yields to the weed-free check, except mesotrione. Metolachlor increased seed yield compared to the weed-free check and MSMA and bromoxynil had comparable yields to the weed-free check at both locations. Results identified possible herbicides to include in a future integrated pest management weed control program for industrial hemp.

In this study, the shape memory response of Ni2MnGa and NiMnCoIn magnetic shape memory alloys was observed under compressive stresses. Ni2MnGa is a magnetic shape memory alloy (MSMA) that has been shown to exhibit fully reversible, stressassisted magnetic field induced phase transformation (MFIPT) in the I X-phase transformation because of a large magnetostress of 7 MPa and small stress hysteresis. The X-phase is a recently discovered phase that is mechanically induced, however, the crystal structure is unknown. To better understand the transformation behavior of Ni2MnGa single crystal with [100] orientation, thermal cycling and pseudoelasticity tests were conducted with the goal of determining the Clausius-Clapeyron relationships for the various phase transformations. This information was then used to construct a stresstemperature phase diagram that illustrates the stress and temperature ranges where MFIPT is possible, as well as where the X-phase may be found. NiMnCoIn is a recently discovered meta-magnetic shape memory alloy (MMSMA) that exhibits unique magnetic properties. The ferromagnetic parent phase and the paramagnetic martensite phase allow the exploitation of the Zeeman energy. To gain a better understanding of the transformation behavior of NiMnCoIn, thermal cycling and pseudoelasticity tests were conducted on single crystals from two different batches with crystallographic orientations along the [100](011), [087], and [25 7 15] directions. A stress-temperature phase diagram was created that illustrates the Clausius- Clapeyron relationships for each orientation and batch. SQUID tests revealed the magnetic response of the alloy as well as the suppression of the martensite start temperature with increasing magnetic field. Pseudoelasticity experiments with and without magnetic field were conducted to experimentally quantify the magnetostress as a function of magnetic field. For the first time, it has been shown that NiMnCoIn is capable of exhibiting magnetostress levels of 18-36 MPa depending upon orientation, as well as nearly 6.5% transformation strain in the [100] direction. The results of this study reveal increased actuation stress levels in NiMnCoIn, which is the main limitation in most MSMAs. With this increased blocking stress, NiMnCoIn is a strong candidate for MFIPT.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-07-03T13:47:46Z No. of bitstreams: 1 MarianaDaCostaBatista_DISSERT.pdf: 1053668 bytes, checksum: 5c4f71a4d8df7785a6c97c28e7c42fe7 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-07-07T14:38:02Z (GMT) No. of bitstreams: 1 MarianaDaCostaBatista_DISSERT.pdf: 1053668 bytes, checksum: 5c4f71a4d8df7785a6c97c28e7c42fe7 (MD5) / Made available in DSpace on 2017-07-07T14:38:02Z (GMT). No. of bitstreams: 1 MarianaDaCostaBatista_DISSERT.pdf: 1053668 bytes, checksum: 5c4f71a4d8df7785a6c97c28e7c42fe7 (MD5) Previous issue date: 2017-04-12 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Agrot?xicos s?o cotidianamente dispostos no meio ambiente atrav?s do uso indiscriminado em lavouras, elimina??o de esgoto bruto e efluentes de esta??es de tratamento, causando danos ? biota aqu?tica e terrestre. Formas de degrada??o que possibilitam a elimina??o completa destes poluentes, que agem oxidando-os a subst?ncias at?xicas, foram tema de investiga??o do presente trabalho. Os processos de oxida??o avan?ada (POAs) s?o apontados como uma inovadora tecnologia com potencial de obter excelentes resultados na oxida??o de subst?ncias org?nicas complexas, pois possibilitam a completa degrada??o de subst?ncias org?nicas oxidando-as a g?s carb?nico, ?gua e ?ons inorg?nicos ou possibilitam a transforma??o de subst?ncias complexas em outras mais biodegrad?veis. No presente trabalho estudamos a viabilidade dos POAs foto-Fenton e sistema UV/H2O2, assim como a fotodegrada??o por radia??o ultravioleta em tr?s pesticidas, sendo eles o 2,4-D (?cido 2,4-diclorofen?xiac?tico), o MSMA (Metilarsenato monoss?dico), e o Glifosato (N-fosfometil glicina). Foi observada a influ?ncia da varia??o de per?xido de hidrog?nio nas taxas de degrada??o dos processos estudados, assim como a efici?ncia da fotodegrada??o por luz UV. Em s?ntese, os melhores resultados se deram para o 2,4-D na concentra??o de 20 mg/L de per?xido de hidrog?nio atingindo aproximadamente 100% de degrada??o nos primeiros 60 minutos de ensaio e glifosato nos tr?s ensaios realizados, sendo o de propor??o [C] [OH-] [1]:[1] o mais efetivo em termos de taxa de degrada??o. Os experimentos apresentaram resultados de degrada??o importantes conferindo efetividade aos processos de oxida??o avan?ada estudados. / Agrochemicals are everyday in the environment by eliminating raw sewage, effluent from treatment plants and indiscriminate use in crops, causing damage to the aquatic and terrestrial biota. Forms of degradation that allow a complete elimination of these pollutants, which act by oxidizing them to substances in the subject, were the subject of research of the present work. Advanced oxidation methods (POAs) emerge as a new technology with the potential to obtain excellent results in the oxidation of complex organic substances, as they allow the complete degradation of organic substances by oxidizing them like carbon dioxide, water and inorganic ions or enabling a transformation of substances Complex in other more biodegradable. There is no work to study the feasibility of photo-Fenton POAs and UV / H2O2 system, as well as ultraviolet photodegradation in three pesticides, 2,4-D (2,4-dichlorophenoxyacetic acid), MSMA (Monosodium methylarsenate ), and Glyphosate (N-phosphonomethyl glycine). It was observed an influence of the hydrogen peroxide variation in the degradation rates of the studied processes, as well as an update of the photodegradation by UV light. Second, the best results were for 2,4-D at the concentration of 20 mg / L of hydrogen peroxide in approximately 100% degradation in the first 60 minutes of the test and glyphosate in the three tests carried out, [C] [OH-] [1]: [1] the most effective in terms of rate of degradation. The experiments showed important degradation results, giving effectiveness to the oxidation processes.

Organoarsenicals such as methylarsenical methylarsenate (MAs(V)) and aromatic arsenicals including roxarsone (4-hydroxy-3-nitrophenylarsenate or Rox(V)) have been extensively used as an herbicide and growth enhancers in animal husbandry, respectively. They undergo environmental degradation to more toxic inorganic arsenite (As(III)) that contaminates crops and drinking water. We previously identified a bacterial gene (arsI) responsible for aerobic MAs(III) demethylation. The gene product, ArsI, is a Fe(II)-dependent extradiol dioxygenase that cleaves the carbon-arsenic (C-As) bond in MAs(III) and trivalent aromatic arsenicals. The objective of this study was to elucidate the ArsI mechanism. Using isothermal titration calorimetry, we determined the dissociation constants (Kd) and ligand-to-protein stoichiometries (N) of ArsI for Fe(II), MAs(III) and aromatic phenyl arsenite. Using a combination of methods including chemical modification, site-directed mutagenesis, and fluorescent spectroscopy, we demonstrated that amino acid residues predicted to participate in Fe(II)-binding (His5-His62-Glu115) and substrate binding (Cys96-Cys97) are all involved in catalysis. Finally, the products of Rox(III) degradation were identified as As(III) and 4-hydroxy-2-nitrophenol, demonstrating that ArsI is a dioxygenase that incorporates one oxygen atom from dioxygen into the carbon and the other to the arsenic to catalyze the cleavage of the C-As bond. These results augment our understanding of the mechanism of this novel C-As lyase.