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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Synthetic Application of Amphoteric Aziridine Aldehydes and alpha-Boryl Aldehydes

He, Zhi 13 December 2012 (has links)
A range of N-H alkynylaziridines were prepared from amphoteric unprotected aziridine aldehydes without protecting-group manipulation. Unprotected alpha -amino allenes can be obtained from these strained propargyl amines via a 9-BBN mediated hydride transfer. Further transformation of alpha -amino allenes to 2,4,6-trisubstituted pyridines was realized. We also developed another class of amphoteric molecules – alpha-boryl aldehydes, equipped with the tetrahedral MIDA boryl group. A wide range of boryl-substituted building blocks or functionalized boronic acid derivatives have been accessed from these bench-stable alpha-borylcarbonyl compounds. Further chemoselective transformations of these alpha-boryl aldehyde derived building blocks have been conducted, where alph-boryl isocyanates, alpha-aminoboronic acids, acylboronates, and borylated heterocycles were achieved through the decarboxylative functionalization of alpha-borylcarboxylic acids.
12

High-resolution laboratory spectroscopy of transient metal-containing molecules

Yu, Shanshan January 2007 (has links)
Ten gaseous transient metal-containing molecules have been synthesized and studied by high resolution spectroscopy. Transient molecules are molecules with a short lifetime, and they play an important role in chemistry because they are reaction intermediates. One of the difficulties faced in studying transient molecules is their typically low concentrations under laboratory conditions. Three types of sources were used to generate these molecules: 1) an emission source that combines a high temperature furnace with an electrical discharge was used to generate SbH, SbD, TeH, TeD, CdH2, CdD2, HZnCl and BeF2; 2) a King furnace (carbon tube furnace) was used to synthesize CoS; 3) a Broida-type oven (metal flow reactor) was used to generate SrOD. Two spectroscopic techniques were employed to study these molecules: 1) Fourier transform infrared emission spectroscopy was used to study SbH, SbD, TeH, TeD, CdH2, CdD2, HZnCl, BeF2, and CoS. 2) Laser-induced fluorescence spectroscopy was employed to study SrOD. One or two lasers were used to excite the SrOD molecules from the ground state to excited electronic states and then these SrOD molecules relaxed back to the ground state by emitting fluorescence, which was detected by a photomultiplier tube. Significantly-improved spectroscopic constants have been obtained for SbH, SbD, TeH and TeD. For SbH and SbD, the infrared X 3– vibration-rotation bands and the near infrared b 1+ – X 3– transition were observed and rotationally analyzed, and a Hund’s case (a) fit was performed for each of the four observed SbH isotopologues. For TeH and TeD, the X 23/2 vibration-rotation bands and the near infrared X 21/2– X 23/2 transition have been observed and rotationally analyzed, and Hund’s case (a) and case (c) fits were performed for each of the ten observed TeH isotopologues. New spectroscopic constants were obtained for HZnCl, CdH2 and CdD2. These three molecules have been successfully generated in the gas phase for the first time. The fundamental band and one hot band were obtained for the H–Zn stretching mode (1) and for the antisymmetric stretching mode (3) of CdH2 and CdD2. A least-squares fit was performed for each of the four observed HZnCl isotopologues and the twelve observed CdH2 isotopologues For the first time, a complete set of molecular constants for all three vibrational frequencies was experimentally determined for BeF2. Thirteen new hot bands were rotationally analyzed and the 1, 2, and3 vibrational frequencies were directly determined by fitting nineteen bands together. The traditional equilibrium vibrational and rotational constants were obtained for BeF2 by simultaneously fitting the observed vibrational term values and B rotational constants. New spectroscopic constants were obtained for two electronic states of CoS and SrOD, respectively. The A 4i – X 4i and B 4i – X 4i transitions of CoS and the and transitions of SrOD were observed for the first time. Hund’s case (c) fits were performed for the CoS transitions and Hund’s case (a) fits were performed for the SrOD transitions.
13

Synthesis and Characterization of Cyclopentadienyl Dicarbonyldiphenylphosphinopropyliron for Migratory Insertion Polymerization

Liu, Yibo January 2013 (has links)
Metal-containing polymers (MCPs) are emerging as a class of interesting materials with promising properties and functions. Although many techniques are available for their synthesis, the range of main-chain MCPs available for material applications is limited. Most well-defined main-chain MCP syntheses rely only on the ring-opening polymerization (ROP) of metallocene monomers, thereby new synthetic approaches for novel MCPs are in high demand. In this study a new polymerization technique, migratory insertion polymerization (MIP), was explored and used to produce novel types of MCPs with asymmetric iron repeat-units connected by phosphine-iron (Ph2P-Fe) and iron-acyl (Fe-CO) bonds in the backbone. This research work involved the synthesis, characterization and polymerization of cyclopentadienyl(dicarbonyl)(diphenylphosphinopropyl)iron (FpP). FpP consists of an Fp functional group capable of undergoing a migratory insertion reaction (MIR) and a phosphine group to assist the MIR. FpP was prepared via the reaction between cyclopentadienyl dicarbonyl iron metalate (Fp anion) and (3-chloropropyl)diphenylphosphine, and was characterized using Fourier transform infrared (FTIR), 1H NMR, 31P NMR, 13C NMR, and ultraviolet-visible (UV-Vis) spectroscopies. The molecules undergo intramolecular cyclization reactions at low concentrations in organic solvents, while polymerization occurs in bulk at 70°C, leading to polymers with number-average molecular weights (Mn) up to 12,000 g/mol and narrow molecular weight distributions (PDI=1.08-1.33). These polymers are soluble in a wide range of organic solvents and have a Tg of 100°C.
14

High-resolution laboratory spectroscopy of transient metal-containing molecules

Yu, Shanshan January 2007 (has links)
Ten gaseous transient metal-containing molecules have been synthesized and studied by high resolution spectroscopy. Transient molecules are molecules with a short lifetime, and they play an important role in chemistry because they are reaction intermediates. One of the difficulties faced in studying transient molecules is their typically low concentrations under laboratory conditions. Three types of sources were used to generate these molecules: 1) an emission source that combines a high temperature furnace with an electrical discharge was used to generate SbH, SbD, TeH, TeD, CdH2, CdD2, HZnCl and BeF2; 2) a King furnace (carbon tube furnace) was used to synthesize CoS; 3) a Broida-type oven (metal flow reactor) was used to generate SrOD. Two spectroscopic techniques were employed to study these molecules: 1) Fourier transform infrared emission spectroscopy was used to study SbH, SbD, TeH, TeD, CdH2, CdD2, HZnCl, BeF2, and CoS. 2) Laser-induced fluorescence spectroscopy was employed to study SrOD. One or two lasers were used to excite the SrOD molecules from the ground state to excited electronic states and then these SrOD molecules relaxed back to the ground state by emitting fluorescence, which was detected by a photomultiplier tube. Significantly-improved spectroscopic constants have been obtained for SbH, SbD, TeH and TeD. For SbH and SbD, the infrared X 3– vibration-rotation bands and the near infrared b 1+ – X 3– transition were observed and rotationally analyzed, and a Hund’s case (a) fit was performed for each of the four observed SbH isotopologues. For TeH and TeD, the X 23/2 vibration-rotation bands and the near infrared X 21/2– X 23/2 transition have been observed and rotationally analyzed, and Hund’s case (a) and case (c) fits were performed for each of the ten observed TeH isotopologues. New spectroscopic constants were obtained for HZnCl, CdH2 and CdD2. These three molecules have been successfully generated in the gas phase for the first time. The fundamental band and one hot band were obtained for the H–Zn stretching mode (1) and for the antisymmetric stretching mode (3) of CdH2 and CdD2. A least-squares fit was performed for each of the four observed HZnCl isotopologues and the twelve observed CdH2 isotopologues For the first time, a complete set of molecular constants for all three vibrational frequencies was experimentally determined for BeF2. Thirteen new hot bands were rotationally analyzed and the 1, 2, and3 vibrational frequencies were directly determined by fitting nineteen bands together. The traditional equilibrium vibrational and rotational constants were obtained for BeF2 by simultaneously fitting the observed vibrational term values and B rotational constants. New spectroscopic constants were obtained for two electronic states of CoS and SrOD, respectively. The A 4i – X 4i and B 4i – X 4i transitions of CoS and the and transitions of SrOD were observed for the first time. Hund’s case (c) fits were performed for the CoS transitions and Hund’s case (a) fits were performed for the SrOD transitions.
15

Study on the Reaction Mechanisms of Gas-liquid Phase of Nitrogen-containing Pollutants over Nanoscale Copper Catalyst

Hung, Chang-Mao 25 June 2003 (has links)
Ammonia is one of valuable chemicals, which are commonly used, in various industrial factors. It is also a typical pollutant, and has a long-term impact on human health for its toxicity characteristics. This study investigated the reaction mechanism of gas-liquid phase in oxidation of ammonia in WAO and SCO processes over copper catalysts. As for lack of the research on activated center of copper catalyst for a long time, it was still not exactly unknown what center was going on affecting activity. Therefore, we conducted the physical and chemical properties on surface of catalyst to realize conversion/activity in oxidation of ammonia over nanoscale copper catalyst. Achievements in oxidation of liquid phase ammonia in WAO process over nanoscale Cu-La-Ce catalysts are as follows: (1) The raising on conversion of ammonia is significantly by adding the molar ratio 7:2:1 of Cu-La-Ce catalyst. (2) The higher temperature the higher conversion, and the increasing space velocity of influent the lower conversion. (3) The reaction rate in WAO process over 7:2:1 catalyst increases with initial pH increasing of solution, 95% conversion of ammonia can be achieved under alkalinity condition. (4) Oxygen supply can promote the decomposition of ammonia at high temperature, above 95% conversion of ammonia can be achieved when total pressure raises at 4.0 MPa. (5) The characteristic peaks of CuO, La2O3 and CeO2 showed from XRD tests indicate the coordination by three peaks probably causes the excellent activity in Cu-La-Ce catalysts; UV-Vis and FTIR analysis results show CuO species dominates the reaction mechanism of liquid phase of WAO process over Cu-La-Ce catalyst which can be used to adsorb the oxygen atom in proceeding the oxidation of ammonia. (6) AEM and TEM analysis results show the outlook of catalyst sites are almost nearly circular and its particle sizes are concentrated in range of nanoscale level; and by EDS and Mapping tests proof elements of Cu, La and Ce are indeed the major components in this catalyst. Achievements in oxidation of liquid phase ammonia in WAO process over nanoscale Cu-ACF catalysts are as follows: (1) The dose of copper on activated carbon fiber support (denoted by ACF) is important in treatment efficiency of pollutants removal; adding at least 5% of copper dosage which can maintain Cu to be a state of +2, it has the catalytic capacity to convert the ammonia in solution. (2) The optimal conversion obtained in 99% under 463 K and 400 mg/l, shows Cu-ACF is also an alterative catalyst. (3) The higher temperature the higher conversion, and the lower nitrogen is. (4) The higher oxygen pressure the higher conversion. (5) From analysis results of BET, FTIR and EA show ACF support has high BET surface area and oxygen-containing function groups, it causes an increasing activity of metal in reaction for the higher activated sites and metal dispersed uniformly on ACF; XRD tests indicate the coordination by CuO and ACF probably causes the excellent activity over Cu-ACF catalysts; UV-Vis and FTIR analysis results show species CuO and ACF both dominate the reaction mechanism of liquid phase of WAO process over Cu-ACF catalyst. (6) AEM and TEM analysis results show the outlook of catalyst sites are almost Nearly long narrowed tube and its diameters are concentrated in range of nanoscale level; and by EDS and XRF (Mapping) tests proof elements of Cu and P are indeed the major components in this catalyst. Achievements in oxidation of gas phase ammonia in SCO process over nanoscale Cu-Ce catalysts are as follows: (1) The great conversion over Cu-Ce catalyst (molar ratio 6:4) obtained under 463 K and 400 mg/l. (2) The higher initial concentration of ammonia the lower conversion is probably due to the intermediates out of completely decomposed in catalytic reaction. (3) From analysis results of BET and EA show this catalyst have high BET surface area and empty hole of oxygen-containing on surface, it causes an increasing activity of metal in reaction for the higher activated sites; XRD tests indicate the coordination by CuO and CeO2 probably causes good activity over Cu-Ce catalysts; UV-Vis and FTIR analysis results show species CuO and CeO2 both dominate the reaction mechanism of gas phase of ammonia in SCO process over Cu-CeO2 catalyst. (4) AEM and TEM analysis results show the outlook of catalyst sites are almost nearly circular and its particle sizes are concentrated in range of nanoscale level; and by EDS and Mapping tests proof elements of Cu and Ce are indeed the major components in this catalyst. Achievements in oxidation of gas phase ammonia in SCO process over nanoscale Pt-Pd-Rh catalyst coated on ceramics are as follows: (1) The 99% conversion over this catalyst can be obtained at 623 K; the higher initial concentration of ammonia ranging from 500 to 1000 mg/l the lower conversion is found. (2) The large amount of N2 and minor amount of NO and NO2 are found in the products after this reaction. (3) XRD tests indicate the coordination by Pt, PdO, Rh and CeO2 probably causes the excellent activity over this catalyst; UV-Vis and FTIR analysis results show species PdO and CeO2 both dominate the reaction mechanism of gas phase of ammonia in SCO process over Pt-Pd-Rh catalyst. (4) AEM and TEM analysis results show the higher initial concentration the higher aged the ceramic support, and the wider sintering of Al2O3 coating layer is. (5) By EDS, XRF and Mapping tests proof elements of Pt, Pd and Rh are indeed the major components dispersed on this ceramic catalyst.
16

An investigation into the synthesis, characterisation and some applications of novel metal-containing polymers and dendrimers of transition metals

Smith, Gregory Stuart January 2003 (has links)
<p>Development in the field of materials science is propagated by the synthesis of polynuclear metal-containing complexes, that exhibit enhanced chemical and physical properties. This thesis describes the synthesis of new metal-containing linear polymers and dendritic molecules.</p> <p>Chapter 1 presents an overview of the field of metal-containing polymers, with particular attention to the synthesis of polymers via condensation polymerisation. This review includes the various types of metal-containing condensation polymers and the applications of these materials, where available. This discussion is followed by a brief summary of metal-containing dendrimers, which includes a concise description of their structure and applications in general.</p> <p>There are two routes to preparing metal-containing polymers. Chapter 2 describes the synthesis of three bifunctional organometallic monomers, of the general type [M]-O-{2,6-(CH2OH)2-4-CH3-C6H2}, where [M] represents the various metal-containing moieties, (&eta / 5-C5H5)(CO)2 Fe(CH2)3 (25), (&eta / 5-C5H4-CH2CH2CH2-)Re(CO)3 (26) and Fpdendr (27). These monomers were prepared using 2,6-bis(hydroxymethyl)-p-cresol as the key reagent. The monomers were used in classical polycondensation reactions with terephthaloyl chloride using ambient temperature solution techniques. This yielded new low molecular weight oligomeric polyesters, that were characterised using FTIR and 1HNMR spectroscopy, differential scanning calorimetry, thermogravimetric analysis and sizeexclusion chromatography.</p> <p>In Chapter 3, an alternate route to metal-containing polymers is described. In this case, bifunctional organic monomers were polymerised to give preformed organic polymers. Two types of organic polymers were prepared, viz. polyesters (with pendant vinyl moieties) and polyimines (with &alpha / -diimine units along the polymer backbone). Functionalisation of these preformed organic polymers with various metal sources was attempted. Hydrozirconation reactions of the vinyl polyesters with Schwartz&rsquo / s reagent, Cp2Zr(H)Cl, were attempted and were largely unsuccessful. Competing reactions with the ester functionality prevailed, preventing the desired reaction. Reaction of the polyimines with PdCl2(COD) yielded insoluble, intractable metal-containing oligomers. Partial characterisation of the complexes is described.</p> <p>The synthesis of new poly(propylene imine) iminopyridyl metallodendrimers is described in Chapter 4. Schiff-base condensation reaction of the commercially available DAB dendrimers with 2-pyridinecarboxaldehyde, gave the dendrimers 51, 52, and 53, with four, eight and sixteen pyridylimine functionalities respectively on the periphery. Successful complexation reactions with PdCl2(COD), PtCl2(COD) and CuCl2 produced the corresponding metal-containing dendrimers, with either PdCl2 (54, 55, 56), PtCl2 (57) or CuCl2 (58) moieties bound on the periphery. The metallodendrimers were insoluble in the more common organic solvents, and were characterised by IR and 1H-NMR spectroscopy and microanalysis where possible. Dendrimers with salicylaldiminato ligands on the periphery were prepared by reacting the DAB dendrimers with salicylaldehyde. These ligands were reacted with various metal acetates in an attempt to prepare new metalcontaining salicylaldimine dendrimers. This work yielded either paramagnetic metal complexes or insoluble, intractable compounds.</p> <p>Chapter 5 describes the applications of the catalyst precursors (54, 55, 56, 57, 58), discussed in Chapter 4, in the polymerisation of ethylene and the use of complexes 54 and 55 as Heck cross-coupling catalyst precursors. The complexes all showed catalytic activity toward ethylene polymerisation. A discussion of their activity, the polyethylene molecular weight and microstructure is presented in this chapter. The precursors 54 and 55 are also effective catalysts in the Heck reactions, coupling iodobenzene with methyl acrylate, styrene and 1-octene in high conversions.</p> <p>General conclusions are given in Chapter 6.</p>
17

Synthetic Application of Amphoteric Aziridine Aldehydes and alpha-Boryl Aldehydes

He, Zhi 13 December 2012 (has links)
A range of N-H alkynylaziridines were prepared from amphoteric unprotected aziridine aldehydes without protecting-group manipulation. Unprotected alpha -amino allenes can be obtained from these strained propargyl amines via a 9-BBN mediated hydride transfer. Further transformation of alpha -amino allenes to 2,4,6-trisubstituted pyridines was realized. We also developed another class of amphoteric molecules – alpha-boryl aldehydes, equipped with the tetrahedral MIDA boryl group. A wide range of boryl-substituted building blocks or functionalized boronic acid derivatives have been accessed from these bench-stable alpha-borylcarbonyl compounds. Further chemoselective transformations of these alpha-boryl aldehyde derived building blocks have been conducted, where alph-boryl isocyanates, alpha-aminoboronic acids, acylboronates, and borylated heterocycles were achieved through the decarboxylative functionalization of alpha-borylcarboxylic acids.
18

Synthesis and Characterization of Cyclopentadienyl Dicarbonyldiphenylphosphinopropyliron for Migratory Insertion Polymerization

Liu, Yibo January 2013 (has links)
Metal-containing polymers (MCPs) are emerging as a class of interesting materials with promising properties and functions. Although many techniques are available for their synthesis, the range of main-chain MCPs available for material applications is limited. Most well-defined main-chain MCP syntheses rely only on the ring-opening polymerization (ROP) of metallocene monomers, thereby new synthetic approaches for novel MCPs are in high demand. In this study a new polymerization technique, migratory insertion polymerization (MIP), was explored and used to produce novel types of MCPs with asymmetric iron repeat-units connected by phosphine-iron (Ph2P-Fe) and iron-acyl (Fe-CO) bonds in the backbone. This research work involved the synthesis, characterization and polymerization of cyclopentadienyl(dicarbonyl)(diphenylphosphinopropyl)iron (FpP). FpP consists of an Fp functional group capable of undergoing a migratory insertion reaction (MIR) and a phosphine group to assist the MIR. FpP was prepared via the reaction between cyclopentadienyl dicarbonyl iron metalate (Fp anion) and (3-chloropropyl)diphenylphosphine, and was characterized using Fourier transform infrared (FTIR), 1H NMR, 31P NMR, 13C NMR, and ultraviolet-visible (UV-Vis) spectroscopies. The molecules undergo intramolecular cyclization reactions at low concentrations in organic solvents, while polymerization occurs in bulk at 70°C, leading to polymers with number-average molecular weights (Mn) up to 12,000 g/mol and narrow molecular weight distributions (PDI=1.08-1.33). These polymers are soluble in a wide range of organic solvents and have a Tg of 100°C.
19

An investigation into the synthesis, characterisation and some applications of novel metal-containing polymers and dendrimers of transition metals

Smith, Gregory Stuart January 2003 (has links)
<p>Development in the field of materials science is propagated by the synthesis of polynuclear metal-containing complexes, that exhibit enhanced chemical and physical properties. This thesis describes the synthesis of new metal-containing linear polymers and dendritic molecules.</p> <p>Chapter 1 presents an overview of the field of metal-containing polymers, with particular attention to the synthesis of polymers via condensation polymerisation. This review includes the various types of metal-containing condensation polymers and the applications of these materials, where available. This discussion is followed by a brief summary of metal-containing dendrimers, which includes a concise description of their structure and applications in general.</p> <p>There are two routes to preparing metal-containing polymers. Chapter 2 describes the synthesis of three bifunctional organometallic monomers, of the general type [M]-O-{2,6-(CH2OH)2-4-CH3-C6H2}, where [M] represents the various metal-containing moieties, (&eta / 5-C5H5)(CO)2 Fe(CH2)3 (25), (&eta / 5-C5H4-CH2CH2CH2-)Re(CO)3 (26) and Fpdendr (27). These monomers were prepared using 2,6-bis(hydroxymethyl)-p-cresol as the key reagent. The monomers were used in classical polycondensation reactions with terephthaloyl chloride using ambient temperature solution techniques. This yielded new low molecular weight oligomeric polyesters, that were characterised using FTIR and 1HNMR spectroscopy, differential scanning calorimetry, thermogravimetric analysis and sizeexclusion chromatography.</p> <p>In Chapter 3, an alternate route to metal-containing polymers is described. In this case, bifunctional organic monomers were polymerised to give preformed organic polymers. Two types of organic polymers were prepared, viz. polyesters (with pendant vinyl moieties) and polyimines (with &alpha / -diimine units along the polymer backbone). Functionalisation of these preformed organic polymers with various metal sources was attempted. Hydrozirconation reactions of the vinyl polyesters with Schwartz&rsquo / s reagent, Cp2Zr(H)Cl, were attempted and were largely unsuccessful. Competing reactions with the ester functionality prevailed, preventing the desired reaction. Reaction of the polyimines with PdCl2(COD) yielded insoluble, intractable metal-containing oligomers. Partial characterisation of the complexes is described.</p> <p>The synthesis of new poly(propylene imine) iminopyridyl metallodendrimers is described in Chapter 4. Schiff-base condensation reaction of the commercially available DAB dendrimers with 2-pyridinecarboxaldehyde, gave the dendrimers 51, 52, and 53, with four, eight and sixteen pyridylimine functionalities respectively on the periphery. Successful complexation reactions with PdCl2(COD), PtCl2(COD) and CuCl2 produced the corresponding metal-containing dendrimers, with either PdCl2 (54, 55, 56), PtCl2 (57) or CuCl2 (58) moieties bound on the periphery. The metallodendrimers were insoluble in the more common organic solvents, and were characterised by IR and 1H-NMR spectroscopy and microanalysis where possible. Dendrimers with salicylaldiminato ligands on the periphery were prepared by reacting the DAB dendrimers with salicylaldehyde. These ligands were reacted with various metal acetates in an attempt to prepare new metalcontaining salicylaldimine dendrimers. This work yielded either paramagnetic metal complexes or insoluble, intractable compounds.</p> <p>Chapter 5 describes the applications of the catalyst precursors (54, 55, 56, 57, 58), discussed in Chapter 4, in the polymerisation of ethylene and the use of complexes 54 and 55 as Heck cross-coupling catalyst precursors. The complexes all showed catalytic activity toward ethylene polymerisation. A discussion of their activity, the polyethylene molecular weight and microstructure is presented in this chapter. The precursors 54 and 55 are also effective catalysts in the Heck reactions, coupling iodobenzene with methyl acrylate, styrene and 1-octene in high conversions.</p> <p>General conclusions are given in Chapter 6.</p>
20

In Vivo Biopotency Evaluation of Chromium-Containing Complexes

Keller, Jay Rulon 01 May 1994 (has links)
Seven chromium-containing complexes were tested for effects on blood glucose regulation, serum cholesterol levels, serum triglyceride levels, and body composition. The compounds included Cr picolinate, Cr chelidonate, chromate, Cr chelidamate, Cr arginate, nichrome, and Cr chloride. The study was divided into two major sections, a rat study and a chicken study. In the rat study all seven chromium-containing complexes were tested. They were administered to the rats in four different testing periods at 1 ppm, 5 ppm, and 25 ppm of chromium. Methods of administration varied for each testing period. After the chromium compounds were administered, a glucose tolerance test (GTT) was conducted on the rats in each of the four experiments. No consistent, significant findings were observed in blood glucose or insulin levels or in blood glucose or insulin change during the GTI. Tissue and blood samples were collected at the end of the study. Liver tissue weights were significantly reduced as the level of chromium supplementation increased. A similar trend was noted in the epididymal fat pad weight, but was not statistically significant. In the chicken study the partitioning effects of Cr picolinate, chromate, Cr chelidamate, Cr arginate, nichrome, and Cr chloride were more closely examined. The chickens were supplemented at 3, 15, and 75 ppm for 8 weeks. No beneficial effects from the supplementation were noted in feed efficiency, total intake, fasting blood glucose and insulin levels, HDL and total cholesterol levels, or serum triglycerides. At the end of 3 weeks the birds supplemented at 3 ppm were heavier than the other treatment birds. At the end of the 8 weeks the birds were sectioned into primal cuts and weighed. No beneficial effects of chromium supplementation were noted in any of the cuts when expressed as a raw weight, percent of dressed weight, or percent of live bird weight. Kidney chromium levels were significantly increased as the level of chromium supplementation increased in the picolinate-, arginate-, and chelidamate-treated groups. Chromium chloride-, picolinate-, arginate-, and chelidamate-treated groups all showed significant increases in liver chromium levels as the level of chromium supplementation increased.

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