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We prepared a seties of tridentate amido diphosphine ligands, including symmetrical [N(o-C6H4PR2)2]- ([R-PNP]- ; R = Ph, iPr, Cy) and unsymmetrical [N(o-C6H4PPh2) (o-C6H4PiPr2)]-. Deprotonation of neutral ligands, H[R-PNP] ( R = Ph, iPr, Cy) or H[Ph-PNP-iPr], with n-BuLi in ether solutions at -35oC produced the lithium complexes, [R-PNP]Li(solv)n ( R = Ph, iPr, Cy; solv = THF, OEt2; n = 1,2) or [Ph-PNP-iPr]Li(solv)n (solv = THF, OEt2; n = 1,2), respectively. The reactions of the lithium complexes or neutral ligands with NiCl2(DME) in THF solutions generated nickel(II) chloride complexes, [R-PNP]NiCl ( R = Ph, iPr, Cy) or [Ph-PNP-iPr]NiCl, which was then reacted with a variety of Grignard reagents to afford the corresponding hydrocarbyl complexes. Of particular interest among the compounds isolated are alkyl complexes that contain £]−hydrogen atoms. The metathetical reactions of nickel(II) chloride complexes with LiNHPh, NaOPh, NaSPh, or NaOtBu, respectively, produced the correspounding nickel anilide, nickel phenolate, nickel thiophenolate and nickel tert-butoxide derivatives. Protonolysis studies of nickel(II)-heteroatom complexes revealed the basic reactivity of these £k-donor ligands. The basicity follows the order OtBu > NHPh > OPh > SPh. Treatment of Ni(COD)2 (COD = cycloocta-1,5-diene) with neutral ligands produced the correspounding four-corrdinate nickel hydride complexes, [R-PNP]NiH (R = Ph, iPr, Cy) or [Ph-PNP-iPr]NiH. The olefin insertion reactions of [iPr-PNP]NiH or [Ph-PNP-iPr]NiH with ethylene, 1-hexene, and norbornene, respectively, generated the corresponding ethyl, n-hexyl, and 2-norbornyl complexes. The formation of [iPr-PNP]Ni(n-hexyl) or [Ph-PNP-iPr]Ni(n-hexyl) is indicative of exclusive 1,2-insertion of 1-hexene. In contrast, styrene inserts into the Ni-H bond of [Ph-PNP-iPr]NiH in an exclusively 2,1-manner to afford [Ph-PNP-iPr]NiCH(Me)Ph. The selective 2,1-insertion products [R-PNP]NiCH(Me)CO2Me (R = Ph, iPr, Cy) or [Ph-PNP-iPr]NiCH(Me)CO2Me were also isolated from the reactions of methyl acrylate with the corresponding nickel hydride complexes. The effects of the phosphorus and olefin substituent on the reactivity and regioselectivity of the olefin insertion reactions are discussed. We also prepared nickel acyl complexes and nickel complexes catalyzed C-N bond formation. In addition to solution NMR spectroscopic data for all new compounds. X-ray diffraction revealed solid structures. A series of five-coordinate aluminum complexes supported by o-phenylene - derived amido diphosphine ligands have been prepared and structurally characterized. Alkane elimination reactions of trialkylaluminum with neutral ligands, H[R-PNP] ( R = Ph, iPr) and H[Ph-PNP-iPr] in toluene solution at -35oC respectively produced the corresponding dialkyl complexes [iPr-PNP]AlR'2, [Ph-PNP]AlR'2 and [iPr-PNP-Ph]AlR'2 (R' = Me, Et, iBu) in high isolated yield. The dihydride complexes [iPr-PNP] AlH2, [Ph-PNP]AlH2 and [iPr-PNP-Ph]AlH2 prepared in one-pot reactions of in situ prepared dichloride precursors with LiAlH4 in THF at room temperature. X-ray diffraction studies revealed a distorted trigonal-bipyramidal structure for these molecules in which the two phosphorus donors are mutually trans. The solution structures of these complexes were all characterized by 1H, 13C, and 31P NMR spectroscopy. The NMR data are indicative of solution C2 symmetry for [iPr-PNP]- and [Ph-PNP]- complexes, whereas they are indicative of C1 for [iPr-PNP-Ph]- derivatives. The 1H NMR spectra of [iPr-PNP]AlR'2, [Ph-PNP]AlR'2 and [iPr-PNP-Ph]AlR'2 (R' = Et, iBu) revealed diastereotopy for the £\-hydrogen atoms in these molecules.

The effluent quality from mining & processing operations is monitored to ensure that maximum allowable limits are not exceeded. Recently, copper concentration levels in the effluent discharge flows of a copper and nickel mining company in Ontario have indicated increasing trends. A chemical particular to the problem is use of diethylenetriamine (DETA) in the process. Adsorption tests were conducted to investigate the ability of various adsorbents to remove and retain copper complexed with DETA and triethylenetetramine (TETA) in solutions. The tests were divided into two sections: gangue adsorbents (silica and pyrrhotite) and high capacity adsorbents (natural bentonite, peat, zeolite Y and zeolite ZSM-5). Pyrrhotite as a sulphide gangue had a greater adsorption capacity than silica for the concentration range studied. At 1 ppm initial concentration, over 80% of copper chelate was removed by minus 400 mesh pyrrhotite compared to 72% of the same size silica. Freundlich and Langmuir isotherm models of adsorption are applicable. However, the Langmuir adsorption isotherm was found to more closely represent the experimental data with a maximum adsorption capacity of 129.9 μg/g for copper complexed with DETA on pyrrhotite. For the high capacity adsorbents, natural bentonite, zeolite Y and peat each worked well at removing the copper chelates. Zeolite Y had the highest capacity for copper chelates and a maximum adsorption capacity of 55.9 mg/g. Freundlich and Langmuir adsorption isotherm models were studied with the Langmuir isotherm model more closely representing the experimental data. iii Studies were also conducted on the effect of temperature. This led to a thermodynamic analysis of adsorption and estimation of activation energies. The standard free energies estimated for adsorption of copper chelated on adsorbents studied were nearly always negative, typically varying from around -2 kJ/mol to -7 kJ/mol with increasing temperature. The activation energy was found to be highest for the natural bentonite system suggesting a strong adsorption (e.g. 40.5 kJ/mol for CuTETA). Desorption experiments on the peat indicated very poor reversal for the process, confirming that the adsorption of copper chelates on high capacity adsorption was indeed very strong. Settling experiments indicated copper chelates were highly effective as coagulants on bentonite. / Thesis (Master, Mining Engineering) -- Queen's University, 2013-12-25 15:00:39.553

This thesis examines the use of anionic nitrogen chelate ligands in coordination-driven self-assembly and small molecule activation. The two classes of anionic nitrogen chelate ligands that were explored are β-diiminate and 4,5-diazafluorenide derivatives. Chapter 2 deals with Pd β-diiminate chemistry. Chloro-bridged dimers served as versatile starting materials, and their reactivity toward pyridine and arylboronic acids was explored. An unusual transmetallation reaction with arylboronic acids triggered the self-assembly of tetrapallada-macrocycles. The formation of the self-assembled tetrapallada-macrocycles is through the generation of new Pd-C bonds. Chapter 3 deals with 4,5-diazafluorenide as an actor ligand in CO2 activation. A reversible formal insertion of CO2 into a remote ligand C-H bond was discovered. A variety of spectator metal centres were used to tune the reactivity of the actor ligand toward CO2. The spectator metal centre could even be replaced entirely with an organic group allowing for the first metal-free reversible tandem CO2 and C-H activation. Chapter 4 deals with the reactivity of dinuclear Rh 4,5-diazafluorenide-9-carboxylate complexes with dihydrogen in an attempt to reduce the trapped CO2 moiety. A series of stepwise stoichiometric reactions with H2, NMR experiments at low temperatures with added PPh3 or CO2, along with 13C-labelling experiments were conducted in an attempt to identify the products of this reaction and gain some mechanistic insight. Chapter 5 deals with using ambidentate 4,5-diazafluorene derivatives to synthesize linkage isomers, heterobimetallic complexes, and self-assembled macrocycles. The synthesis a new ligand family, 3,6-substituted 4,5-diazafluorene ligands is presented, along with coordination chemistry towards a {RuCp*}+ fragment. Finally in Chapter 6 the coordination chemistry of 3,6-diaryl substituted 4,5-diazafluorene derivatives was explored with the goal of generating low-coordinate species for the activation of small molecules, especially N2. The synthesis of the first trialkylborohydride complex of vanadium is presented.

Universiẗat, Diss., 1994--Duisburg.

Universiẗat, Diss., 2002--Jena.

Submitted by Natália Martins Teixeira null (nataliamartinsteixeira@hotmail.com) on 2016-06-21T14:09:42Z No. of bitstreams: 1 Natália Martins Teixeira - Dissertação.pdf: 713591 bytes, checksum: c3efeb3b351738abb465f7c50eeebf9a (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-06-23T13:57:32Z (GMT) No. of bitstreams: 1 teixeira_nm_me_dra.pdf: 713591 bytes, checksum: c3efeb3b351738abb465f7c50eeebf9a (MD5) / Made available in DSpace on 2016-06-23T13:57:32Z (GMT). No. of bitstreams: 1 teixeira_nm_me_dra.pdf: 713591 bytes, checksum: c3efeb3b351738abb465f7c50eeebf9a (MD5) Previous issue date: 2016-04-26 / Com a intensificação da produção pecuária são necessários avanços no manejo e adubação das plantas forrageiras, para aumentar a produtividade e manter-se competitivo no setor. A utilização de tecnologias, como a adubação foliar com micronutrientes, torna-se uma importante ferramenta para atingir a plenitude na produção agropecuária. O experimento foi conduzido em casa de vegetação da UNESP, Campus de Dracena, em vasos com capacidade para 4 dm3 de terra, com o objetivo de avaliar a produção de massa seca, teor e quantidade de nutrientes e qualidade bromatológica da forrageira Megathyrsus maximum (syn. Panicum maximum) cv. Mombaça adubado com zinco quelatizado, via foliar, em dois solos com distinta disponibilidade de Zn. O delineamento experimental foi inteiramente casualizado com quatro repetições. Os tratamentos foram arranjados em esquema fatorial 6X2, sendo seis doses foliares de zinco quelatizado, e duas condições de solo (com baixo e médio teor de Zn), acrescidos de um tratamento com sulfato de zinco e dois tratamentos com coquetel de nutrientes. Foram utilizados o Neossolo Quartzarênico, distrófico, fase cerrado, com baixo teor de zinco e o Argissolo Vermelho Amarelo, distrófico, com teores médios de zinco. Nas condições em que foi realizada a pesquisa, os resultados permitem concluir que: a aplicação foliar de Zn quelatizado, coquetel de nutrientes e sulfato de zinco não influenciaram a produção de massa seca do capim-mombaça; o teor de Zn na massa seca do capim-mombaça foi diretamente proporcional à dose de Zn quelatizado via foliar, contribuindo com o fornecimento do micronutriente para alimentação animal; o Zn na adubação foliar reduz os teores de K na massa seca do capim-mombaça cultivado em Argissolo; o teor de Zn no Argissolo aumentou com a aplicação de Zn quelatizado via foliar; o teor de FDN, FDA e PB no capim-mombaça não foi afetado em função da aplicação de Zn quelatizado via foliar; a massa do sistema radicular do capim-mombaça reduziu com a aplicação de Zn quelatizado via foliar no Neossolo Quartzarênico e não apresentou efeito no Argissolo; novos trabalhos de pesquisa devem ser realizados envolvendo o estudo de Zn e adubação foliar para avaliar seus efeitos em plantas forrageiras e suas interações com demais nutrientes. / With the intensification of livestock production are needed advances in the management and fertilization of forage crops, to enhance productivity, reducing costs and remaining competitive in the industry. The use of technologies such as foliar fertilizer with micronutrients, it becomes an important tool to achieve fulfillment in agricultural production. The experiment was conducted at UNESP greenhouse, Campus de Dracena, situated 421 meters above sea level, 21 ° 27 'south latitude and 51 ° 36' west longitude, in pots with a capacity of 4 dm3 of land, in order to evaluate the dry matter production, content and amount of nutrients and chemical quality of the forage Megathyrsus maximum (syn. Panicum maximum) cv. Mombasa fertilized with chelated zinc, foliar, in two soils with different availability of Zn. The experimental design was completely randomized with four replications. The treatments were arranged in a factorial scheme 6X2, six leaf doses of zinc chelate, and two soil conditions (low and medium Zn content), plus a treatment with zinc sulfate and two treatments with cocktail nutrients. The Entisol were used, dystrophic, cerrado phase, with low zinc content and Ultisol, dystrophic, with average zinc content. The conditions under which the survey was conducted, the results showed that: foliar application of chelated Zn cocktail of nutrients and zinc sulfate did not affect the dry matter production of mombaça grass; Zn content in the dry mass of mombaça grass was directly proportional to the dose of chelated Zn foliar contributing to the provision of micronutrient for animal feed; Zn in foliar fertilization reduces the K in the dry mass of mombaça grass grown Ultisol; Zn content in Ultisol increased with the application of chelated Zn foliar; NDF, ADF and CP in mombaça was not affected due to the application of Zn chelated foliar; the mass of the root system of mombaça grass reduced with the application of chelated Zn foliar in Entisol and had no effect on Ultisol; new research work should be carried out involving the study of Zn and foliar application to evaluate its effects on forage plants and their interactions with other nutrients.

Cassava (Manihot esculenta, Crantz) is considered a vital agricultural crop due to its role as a staple food for low-income populations, primarily in the North and Northeast of Brazil, and is used as raw material for the manufacturing of a number of products such as flour and starch. During the manufacturing of these products, a potentially toxic liquid residue called manipueira is produced. Due to its high content of hydrogen cyanide (HCN), this residue (which originates during the initial processing stages of the cassava) has very limited use. After undergoing a process of HCN volatilization however, it may then be used for the fertilization, to create insecticides, nematicides and herbicides. Manipueira has contains glucose, cyanogenic glycosides, organic substances and mineral nutrients, in particular potassium (K), nitrogen (N), as well as micronutrients - all guaranteeing its potential as a fertilizer. The aim of this study was to evaluate the effect of cassava as an alternative to zinc chelates in bean cultivation. The study was carried out in a greenhouse at the Federal University of Sergipe. The experimental design involved random blocks in 5x4 factorial arrangement, with five repetitions and five treatment sources: The experimental design was randomized blocks in a factorial arrangement 5 x 4, the treatments were five sources (A-H2O; Manipueira1 B-2 ml dm-3, C-4 manipueira2 ml dm-3, D-manipueira3 8mL dm3, E-EDTA) with four levels of zinc (0,0; 1,3;2,6 and 5,2 mg Zn dm3), applied to the soil, whit four replication. The soil was collected from the rural campus at the Federal University of Sergipe and a sample was taken for chemical analysis. The soil was placed in 16 L-1 b plastic bags and dolomitic lime was used for liming of the soil. The fertilizations were performed with 100 mg of phosphorus (P) dm-3 and 100mg of potassium (K) dm-3, in the form of triple super phosphate and potassium chloride. The lime and fertilizers were combined with the soil contained in the plastic bags and were then transferred to 100 containers with a soil capacity of 13 dm-3. A quantity of 50 mg of N dm-3 in the form of urea was applied for sowing fertilization. Sowing was carried out using six Pearl bean cultivar seeds per container. Seven days after the emergence of shoots, thinning was carried out to remove plant surplus, leaving two plants per container, and the treatments were applied. Once most of the plants had reached the phenological stage of flowering (R6) harvesting was carried out. The parameters examined were physico-chemical analysis (in the manipueira) and growth and nutritional analyses in the bean plant tissue (leaf and root). The use of cassava as quelatizante of micronutrients on dry bean crop had a satisfactory result in treatments EDTA and Man ¹.If necessary more studies of manipueira as chelate micronutrients in other cultures. / A mandioca (Manihot esculenta Crantz) é uma cultura agrícola muito importante por constituir a base alimentar das populações de baixa renda principalmente na região Nordeste, sendo matéria prima na fabricação de diversos produtos como a farinha e fécula. No processo de fabricação destes produtos é gerado a manipueira um resíduo líquido potencialmente poluidor a manipueira. Este resíduo, originado nas etapas de processamento da mandioca tem aproveitamento muito restrito por apresentar alto teor de ácido cianídrico (HCN).No entanto, com a volatilização do HCN a manipueira pode ser usada como fertilizante, inseticida, nematicida e herbicida. A manipueira possui principalmente glicose, glicosídeos cianogênicos, substâncias orgânicas e elementos minerais, como K, N e micronutrientes que sustentam a potencialidade como adubo. A presente pesquisa teve como objetivo avaliar o efeito da manipueira como alternativa de quelatizante de zinco para o feijoeiro (Phaseolus vulgaris L.). O trabalho foi desenvolvido na Universidade Federal de Sergipe em condição de casa de vegetação. O delineamento experimental utilizado foi em blocos casualizados, disposto em arranjo fatorial 5 x 4, sendo que os tratamentos foram cinco fontes (A H2O; B- Manipueira1 (2 ml dm-3), C manipueira2 (4 ml dm-3); D manipueira3 (8 mL dm-3); E- EDTA) e quatro níveis de zinco (0,0; 1,3; 2,6 e 5,2 mg.dm-3 de Zn), aplicados no solo, com quatro repetições. O solo utilizado como substrato foi proveniente do campus Rural da Universidade Federal de Sergipe, foi retirada uma amostra para análise química.Após a coleta do solo, este foi colocado em sacos de plásticos de 16 L-1. Posteriormente, foi realizada a calagem, com calcário dolomítico, e em seguida foram realizadas as adubações com 100 mg.dm-3 de P, 100 mg.dm-3 de K. O calcário e os adubos foram misturados ao solo contido nos sacos plásticos e transferidos para os 100 vasos com capacidade de 13 dm3 de solo. Na adubação de semeadura foram aplicados 50 mg.dm-3 de N, na forma de uréia. A semeadura foi realizada utilizando seis sementes de feijão da Cv. Pérola por vaso. Após sete dias da emergência das plântulas foram realizados os desbastes, deixando duas plantas por vaso, e em seguida aplicados os tratamentos.Quando a maioria das plantas estavam no estádio fenológico de floração (R6) foi realizada a colheita dos tratamentos. Verificou-se que as aplicações de quelato biológico (manipueira) no solo resultaram em teores crescente de zinco na parte aérea do feijoeiro. Os ácidos orgânicos da manipueira apresentou-se eficiente na quelatização dos nutrientes estudados.

The objective of this work was the development of an efficient adsorbent for irreversible immobilization of heavy metals in contaminated soils. The adsorbent was prepared by pillaring of montmorillonite with silica followed by grafting of a chelate ligand on its surface. Obtained adsorbent was mesoporous with high content of adsorption sites. Its structure was studied by BET adsorption of N2, dynamic light scattering, and scanning electron microscopy. The adsorption capacity of the organoclay was measured by its mixing with contaminated kaolin and soil samples and by analysis of heavy metal contents in leachate. Deionized water and 50% acetic acid were used for leaching of metals from the samples. As it was demonstrated by the experiments, the adsorbent was efficient in immobilization of heavy metals not only in neutral aqueous media but also in the presence of weak acid. As a result, the adsorbent can be used for reduction of heavy metal leaching from contaminated sites.

The objective of this work was the development of an efficient adsorbent for irreversible immobilization of heavy metals in contaminated soils. The adsorbent was prepared by pillaring of montmorillonite with silica followed by grafting of a chelate ligand on its surface. Obtained adsorbent was mesoporous with high content of adsorption sites. Its structure was studied by BET adsorption of N2, dynamic light scattering, and scanning electron microscopy. The adsorption capacity of the organoclay was measured by its mixing with contaminated kaolin and soil samples and by analysis of heavy metal contents in leachate. Deionized water and 50% acetic acid were used for leaching of metals from the samples. As it was demonstrated by the experiments, the adsorbent was efficient in immobilization of heavy metals not only in neutral aqueous media but also in the presence of weak acid. As a result, the adsorbent can be used for reduction of heavy metal leaching from contaminated sites.