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Thermodynamics of the interaction of divalent manganese with histamine and certain associated substancesButler, Janis Broman. January 1961 (has links)
Call number: LD2668 .T4 1961 B88
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Manganese response and nutrient uptake in conventional and glyphosate-resistant soybeanLoecker, Jami L. January 1900 (has links)
Master of Science / Department of Agronomy / Nathan O. Nelson / Glyphosate-resistant (GR) soybean cultivars are widely accepted in the United States. Glyphosate-resistance provides many benefits to production agriculture, yet GR soybeans may require some additional management practices. The objectives of this research are to (a) determine response of GR and conventional (CV) soybean near isoline to manganese fertilization, (b) determine nutrient concentration and uptake in GR and CV soybean, (c) determine differences in yield of GR and CV soybean varieties, (d) quantifying Mn uptake when glyphosate is and is not applied to glyphosate-resistant soybean, and (e) determine glyphosate effect on soybean response to Mn treatments. A field study was conducted at 5 locations in Kansas from 2006 through 2007. Manganese soil test levels ranged from 4 to 52 mg Mn/kg. Soybean (near isoline) varieties were planted at each location in a split-block design with 4 replications. Manganese treatments consisted of soil-applied MnSO[subscript]4 at 0, 2.8, 5.6, and 8.4 kg Mn/ha and foliar applied Mn at 0.22 and 0.45 kg Mn/ha. Leaf tissue and whole plant samples were taken at approximately R1, R3, and R6 growth stages and analyzed for N, P, K, Mn, and other nutrient concentrations. Few significant differences were found between varieties for concentration of any nutrient. Overall nutrient uptake under optimal growth conditions was greater in GR soybean than CV soybean varieties. There were no yield differences between GR and CV soybean varieties at low yielding locations (< 3.3 Mg/ha). In high yielding environments, CV soybean yield was greater than GR soybean yield for the 0 kg Mn/ha rate. However, granular Mn additions increased yield of GR soybean but did not affect CV soybean yield while foliar Mn treatments at high yielding locations increased yields in GR and CV soybean. In addition, a greenhouse study was conducted with a completely randomized block design having 5 blocks. Manganese treatments in the greenhouse study consisted of soil-applied MnSO[subscript]4 at 0, 8.5, 17, and 25.5 mg Mn/pot and foliar applications of 0.66 and 1.33 mg Mn/pot. Treatments were with and without glyphosate applications. Glyphosate applications did not alter Mn concentrations or total Mn uptake in the soybean biomass.
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EVALUATION OF COMMERCIAL-OFF-THE-SHELF LITHIUM BATTERIES FOR USE IN BALLISTIC TELEMETRY SYSTEMSBukowski, Edward F. 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / As technological advances continue to be made in the commercial sectors of portable and
wireless communication products, additional advancements in battery technology have also been
made. These advancements have allowed for the rapid growth of a large variety of commercially
available batteries which have the capability to meet or even exceed the current power and size
requirements for numerous ballistic telemetry systems. The replacement of a custom built
battery with a COTS battery would provide immediate advantages such as lower cost, shorter
lead times and higher availability. The overall objective of this paper is to provide ballistic
telemetry systems engineers and designers with multiple low cost, readily available alternatives
to traditional custom made power sources.
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Bio-inorganic chemistry of manganese and titaniumBihari, Shailja January 2002 (has links)
A wide range of metals are transported in the body by the protein transferrin, including both essential metal ions and probably also metals used in therapeutic agents. The metal binding sites on transferrin contain tyrosine, histidine and aspartate ligands. This thesis is concerned with studies of the essential metal ion manganese, and with titanium, which is used in anticancer agents. In order to aid the characterisation of Mn(III) and Ti(IV) transferrins, the Mn(III) and Ti(IV) complexes with the model ligand ethylenebis[(a-hydroxyphenyl)glycine](H₄EHPG) have been studied. The Mn(III) complexes rac-Na[Mn(EHPG)].3H₂0 (1) and rac,mesoNa[Mn(EHPG)].H₂0 (2), have been prepared and their X-ray crystal structures determined. Complex 1 contains N(S,S)C(R,R) configurations at the N and C stereogenic centres, whilst in the unit cell of complex 2 there are two independent molecules, 2a (mesa) and 2b (rac), with N(R,R)C(S,R) and N(R,R)C(S,S) configurations, respectively. Enantiomers of each complex are also present. The Mn(III) centres have Jahn-Teller-distorted octahedral geometry, with two long bonds and four short bonds. ¹H NMR spectra of these high-spin d⁴ paramagnetic complexes are reported. These complexes give rise to similar ligand (phenolate)-tometal charge-transfer bands as Mn(III)-transferrin. Dissociation of Mn(III) from EHPG occurs below pH 3.4. The Ti(IV) complex of rac-[Ti(EHPG)(H₂0)].1113H₂0 (3) has also been prepared and the X-ray crystal structure determined. All previously-reported crystalline racEHPG metal complexes contain N(S,S)C(R,R), or N(R,R)C(S,S) isomers, whereas 3 unexpectedly contains the N(S,S)C(S,S) and N(R,R)C(R,R) forms. 2D NMR studies indicate that 3 has a similar structure in solution to that in the solid state. A ligand (phenolate)-to-metal charge transfer band was observed at 386 nm, similar to that seen for Ti(IV)-transferrin. Ti(IV)EHPG was stable at pH values down to 1, however, the complex decomposed above pH 7. Mn(III)-transferrin complexes were prepared by air oxidation of Mn(II) in the presence of transferrin. The oxidation state of manganese bound to transferrin was Abstract confirmed by K edge EXAFS. Analysis of the EXAFS data revealed that the metal centre is also Jahn-Teller distorted but with four long bonds and two short bonds, i.e. an inverse distortion to that seen in the Mn(III)EHPG model complexes. Attempts to prepare other Mn(III) complexes which might be suitable for studies of Mn transfer to proteins are described and include cyclam and bicyclam as ligands. The crystal structure of [Mn(cyclam)Ch]Cl₂H₂0 was determined, and contained two long axial Mn-Cl bonds of 2.5249 Å. This complex was shown by electronic absorption spectroscopy to undergo a complicated series of reactions in aqueous solution. K edge EXAFS measurements suggested that at least one Cl ligand dissociated from the complex in aqueous solution. The hydrolysis was shown to be inhibited by the presence of fluoride.
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Manganese complexes as catalase and superoxide dismutase mimics : structure and reactivity relationshipsKose, Muhammet January 2012 (has links)
Macrocycle (H2L1) was prepared by a Schiff base condensation reaction of 2,6-diformylpyridine and 1,3-diamino-2-propanol in the presence of Ba(II) as template ion. Seven-coordinate Mn(II) complexes were prepared by transmetallation reactions of the initial [Ba(H2L1)(μ1,2-ClO4)]2(ClO4)2 complex. Two mononuclear, ring-contracted complexes were obtained when methanol or ethanol were used as solvents in transmetallation reactions. For both complexes, X-ray analysis showed that the H2L1 macrocycle undergoes a ring-contraction via addition of methanol or ethanol across one imine bond, followed by a nucleophilic addition of the secondary amine across an adjacent imine bond resulting in a six-membered, hexahydropyrimidine ring sitting in a chair conformation. The ring-contraction process reduces the size of the cavity in the macrocycle to accommodate one Mn(II) ion in the macrocycle. The macrocyclic tetraimine ligand (H2L1) gave access to the polynuclear, ring-expanded assemblies, [Mn4(H2L*)Cl4][MnCl4] and [Mn4(H2L*)(N3)4](ClO4)2, when acetonitrile was used as a solvent. The macrocycle (H2L1) undergoes rearrangement from a 20-membered to a 40-membered tetranuclear Mn(II) complex. Manganese complexes of acyclic ligands, derived from 2,6-diformylpyridine and several aminoalcohols and aminophenols, were prepared and structurally characterised by X-ray crystallography. Most of the complexes are seven-coordinate with approximate pentagonal bipyramidal geometry, however, some five, six and seven-coordinate complexes were identified. Asymmetric and symmetric tripodal Schiff base ligands and their manganese complexes were also prepared and characterised. Additionally, N-alkylated benzimidazole 2,6-bis(1-butyl-1H-benzo[d]imidazol-2-yl)pyridine and its Mn(II) complexes were prepared and characterised. The potential application of the complexes has been tested in two main areas: (a) as new catalase mimics and (b) as new superoxide dismutase (SOD) mimics. The trinuclear, acyclic complex, [Mn3(L9)2(OAc)2(MeOH)2] 2MeOH, derived from 2,6-diformylpyridine and 2-aminophenol, was found to be the most efficient catalase mimic of the tested complexes with approximately 500 molecules of H2O2 broken down per second for each complex during the fastest rate of activity. Catalase testing showed that an increase of the arm size of the tripodal complexes produced an increase in activity overall for the complexes. Most of the complexes tested for catalase activity showed an induction period prior to the activity being observed. This may be due to a rearrangement occurring before catalase activity is observed. The tripodal complex, [Mn(L18)](ClO4)2 is the only complex to show a catalase activity without added base, but with a long induction period. The results that are presented indicate that the axial ligands have an effect on both the rate of catalase activity and the observed induction period. The SOD results indicated that the complex, [Mn(H2L6)Cl(H2O)]Cl H2O, derived from 2,6-diformylpyridine and 1 aminopropan-2-ol, shows the highest SOD activity amongst the complexes prepared, with a rate of 2.05x106 M-1s-1 and the IC50 value of 0.78 μM. Most of the complexes showed SOD activity with a rate around 105-106 M-1s-1. The SOD results showed that the axial ligands have an effect on SOD activity; strongly bound ligands such as thiocyanate and azide generally result in lower SOD activity. Most of the complexes showed both SOD and catalase activity. Ring-contracted complexes, [Mn(H3L2)(NCS)2] and [Mn(H3L3)(NCS)2], show high rates of superoxide dismutase activity but possess limited catalase activity.
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Syntheses and reactions of copper and manganese complexes of tetradentate polyanionic chelating ligands and their applications incarbon-heteroatom bond formation reactions朱煒章, Chu, Wai-cheung. January 1997 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
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Oxo and Imido transfer reactions mediated by ruthenium and manganese complexes containing chiral porphyrin and oxazolinyl ligands黎達成, Lai, Tat-shing. January 1998 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
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Nonplanar and sterically encumbered ruthenium porphyrins and catalyticreactivity of ruthenium and manganese porphyrin complexes supported onMCM-41劉純晶, Liu, Chunjing. January 1998 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
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Roles of manganese superoxide dismutase in ovarian cancerWong, Kwan-yeung., 黃君揚. January 2007 (has links)
published_or_final_version / abstract / Biological Sciences / Master / Master of Philosophy
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The significance and biological/abiological interplay in Fe(III) and Mn(IV) reduction in contrasting sedimentsKelly, Julie Ann January 1997 (has links)
No description available.
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