Search

The aim of this study was to examine the effects of various levels of supplemental calcium iodate (CI) on productive performance, egg quality, blood indices and iodine (I) accumulation in the eggs in commercial laying hens. A total of 240 White Leghorn layers (Hy-line W36) were divided through a completely randomized design into six treatments with five replicates and eight hens per each at 32 weeks of age. This experiment lasted for 12 weeks. Concentrations of I in the mash diets were 0.74, 3.13, 5.57, 8.11, 10.65 and 12.94 mg I/kg of feed in treatments 1-6 respectively. The added doses of CI were included 0.0 (control), 2.5, 5.0, 7.5, 10.0 and 12.5 mg/kg of diet for treatments 1-6 respectively. There were no significant differences in productive performance among the treatments. The highest eggshell strength was observed in group fed diet containing 3.13 mg I/kg (p = .014). The highest percentage of calcium and lowest percentage of phosphorus in eggshell were observed in group fed diet containing 12.94 mg I/kg (p = .0001). Feeding hens with diet containing 12.94 mg I/kg increased serum triiodothyronine-to-thyroxine ratio (p = .0001). Serum alanine aminotransferase activity in hens fed diet containing 12.94 mg I/kg was significantly more than control (p = .041). Blood Serum triglycerides in hens fed diet containing 8.11 mg I/kg were significantly higher than control (p = .0001). Edible fraction of the eggs of birds fed diet containing 12.94 mg I/kg was enriched by I almost 3 times more than those fed diet containing 0.74 mg I/kg. The results suggested that egg production, egg mass, feed intake and feed conversion ratio were not significantly affected by dietary I levels. Iodine accumulation in the eggs were increased by increasing dietary I levels and the level of 10 mg/kg CI could supply I enrichment of the eggs.

Currently there is a need for specialized pyrotechnic materials to combat the threat of biological weapons. Materials have been characterized based on their potential to produce heat and molecular iodine gas (I2) to kill spore-forming bacteria (e. g. anthrax). One formulation, already proven to kill anthrax simulants, is diiodine pentoxide with aluminum; however, it suffers from poor stability and storage problems. The heat and iodine gas output from this mixture and candidate replacement mixtures were measured with bomb calorimetry and extraction and analysis of I2 by UV-Vis. Of the mixtures analyzed, calcium iodate and aluminum was found to be the highest producer of I2. The heat output of this mixture and others can be tuned by adding more fuel, with the cost of some iodine. Products of combustion were analyzed by thermal analysis (SDT), XPS, XRD, and LC/MS. Evidence for various metal iodides and metal oxides was collected with these methods.

Iodine bearing reactive materials and fuel additives are being developed to inactivate harmful aerosolized spores and bacteria by combined thermal and chemical effects. Nanocomposite thermites with aluminum and boron serving as fuels and calcium iodate as an oxidizer were prepared by arrested reactive milling. Both materials contained 80 wt % of calcium iodate. Morphology and particle sizes of the prepared materials were characterized using scanning electron microscopy (SEM). Both powders comprised particles finer than ca. 10 μm with fuel and oxidizer mixed on the submicrometer scale. Powders were exposed to room air to assess their stability. They were ignited as a thin coating on an electrically heated filament. Powders were injected in an air-acetylene flame to observe combustion of individual particles. Pressed pellets for both prepared materials were prepared and ignited using a CO2 beam. Al ⋅ Ca(IO3)2 oxidizes rapidly in room air, whereas no aging was detected for B ⋅ Ca(IO3)2. Ignition of Al ⋅ Ca(IO3)2 occurs around 1150 K, after both aluminum and calcium iodate melt. Ignition is accompanied by ejection of sintered particles undergoing microexplosions while they are combusting. Ignition of B ⋅ Ca(IO3)2 occurs between 600 and 700 K, before either of the components melt. Combustion is accompanied by the formation of a luminous halo above the material, suggesting a vapor-phase reaction involving boron suboxides. Longer ignition delays are observed for the pellets of Al ⋅ Ca(IO3)2 heated by the CO2 laser beam compared to similar pellets of B ⋅ Ca(IO3)2. Burn rates of B ⋅ Ca(IO3)2 pellets are nearly twice as fast as those of Al ⋅ Ca(IO3)2, primarily due to the lower ignition temperature for the boron-based thermite. The flame temperatures obtained from the time-integrated optical spectra are close to 2140 and 2060 K for Al ⋅ Ca(IO3)2 and B ⋅ Ca(IO3)2, respectively. Individual particles of B ⋅ Ca(IO3)2 injected into an air-acetylene flame burn slower than similar Al ⋅ Ca(IO3)2 particles. Based on their better stability, lower ignition temperatures, shorter ignition delays, and longer burn times leading to a more gradual release of iodine, B ⋅ Ca(IO3)2 composites are suggested to be better suited as components of energetic formulations aimed to defeat stockpiles of biological weapons.

Alumina green bodies were prepared by direct coagulation casting via increasing high valence counter ions (DCC-HVCI) method. Influence of calcium iodate concentration, coagulation temperature, and the solid loading on the compressive strength of coagulated bodies was investigated. The results show that the wet-coagulated bodies display higher compressive strength than dried ones. The wet strength is above 2.0 MPa which is about one order higher than that prepared by DCC method, whereas the dried strength is in the range of 1.0 MPa. The wet-coagulated body shows elastic deformation, whereas the dried body exhibits typical brittle failure behavior. The mechanism of high wet strength obtained by DCC-HVCI is also proposed. The coagulated bodies prepared from slurries of alumina loading in the range of 50 vol% showed linear shrinkage of 2.6% after drying at 80°C for 24 h. The sample with the powder content of 50 vol% displays a narrow average pore channel size, showing a mean pore diameter of 40 nm. A homogeneous green body and high wet strength can be obtained via the DCC-HVCI method.

A new direct coagulation casting of aqueous alumina suspension was developed via controlled release of high valence counter ions from calcium iodate with increase in the temperature from 55°C to 70°C. The influence of calcium iodate on the rheology of alumina suspension was investigated. A small amount of calcium iodate increased the viscosity of the concentrated alumina suspension at high temperature and finally transformed it into a wet-coagulated body. The mechanism of coagulation is proposed such as that the solubility of calcium iodate increases with increase in temperature. The high valence Ca2+ ions diffuse into the double electrical layer of alumina particles surface through electrostatic attraction, reduces the zeta potential, hence decreases repulsive force between particles. Also reaction between Ca2+ and citrate leads to insufficient dispersant coverage on the particle surface. Both factors contribute to the coagulation of the suspension. The coagulation time was from 1 to 4 h by maintaining the temperature in the range of 55°C–70°C. The wet-coagulated bodies prepared from 50 vol% alumina suspension showed a high compressive strength of 2.6–3.2 MPa with uniform microstructure. The relative density of sintered sample is 99.4% at 1550 °C for 2 h with perfect microstructure.

Neutron powder diffraction experiments were performed on highly deuterated calcium iodate monohydrate (bruggenite) to examine possible H/D enrichment effects. The title compound is built up of distorded CaO 8 quadratic antiprisms. The iodate ions form layers parallel to (100), revealing relativity short interionic I...O distances of 3.02 and 2.90 A. The water molecules are trigonally planar coordinated (2 IO - 3 , 1 Ca 2+ , site symmetry C 1 ), forming asymmetric hydrogen bonds of different strengths to adjacent iodate ions. Deviation from random distribution of the H atoms has been established.

Single crystals of calcium iodate, monohydrate [Ca(IO 3 ) 2 , H 2 O] have been grown by gel technique. Prismatic, prismatic pyramidal, needle shaped and hopper crystals were obtained. These crystals were also grown by doping impurities such as copper and iron. Kinetics of growth parameters was investigated. Structural analysis was carried out by using X-ray powder diffraction method. Microtopographical study of the habit faces, such as prismatic and pyramidal, of as grown crystals was carried out. Some surface structures are reported. These crystals were etched by various etchants and appropriate etchant is reported.

Ca(BrO3)2 und Ca(IO)3 sowie deren Hydrate wurden mit Hilfe thermoanalytischer, rontgenographischer und IR- sowie Raman- spektroskopischer Methoden untersucht. Charakterisiert wurden: Ca(IO3)2 · 6 H2O oF216, die isotypen Monohydrate mP48 Ca(BrO3)2 νH2O und Ca(IO3)2 I (Lautarit) mP36, Ca(IO3)2 II und Ca(BrO3)2. Die Kristallstruktur von Ca(IO3)2 νH2O (Bruggenit) (Raumgruppe P21/c, Z = 4) wurde mit Hilfe von Rontgeneinkristalldaten (MoKα) bestimmt (R = 4,87%, 3888 Reflexe mit Io > 3σ1). Die Strukturen der bisher bekannten Halogenate von Erdalkalimetallen werden im Hinblick auf die energetische (Schwingungsfrequenzen) und geometrische (Bindungslangen) Verzerrung der XO3−-Ionen sowie der Starke der Wasserstoffbrucken diskutiert. On Calcium Bromated and Iodates – Crystal Structure, X-Ray, IR and Raman Spectroscopical and Thermoanalytical Investigations The phase relationships (and both decomposition and disproportionation)of bromates and iodates of alkaline earth metals are studied by means of thermal analyses (DTA, DSC, TG) and (high-temperature) X-Ray, IR-, and (high-temperature) Raman spectroscopic measurements. The following compounds have been established: Ca(IO3)2 · 6 H2O oF216, the isotypic Ca(BrO3)2 · H2O and Ca(IO3)2 · H2O mP48, Ca(IO3)2 I (Lautarit) mP36, Ca(IO3)2 II and Ca(BrO3)2. The Crystal structure of Ca(IO3)2 · H2O (bruggenite) (space group P21/c, Z = 4) has been determined by single crystal X-ray diffraction (MoKα). The final R value for 3888 reflections with Io > 3σ1 is 0.0487. The structures of bromates and iodates of alkaline earth metals known so far are discussed with respect to the energetic (mode frequencies) and geometric (bond lengths) distortion of the XO3–ions as well as the strengths of H-bonds present in the respective hydrates.

Single crystals of calcium iodate, monohydrate [Ca(IO 3 ) 2 , H 2 O] have been grown by gel technique. Prismatic, prismatic pyramidal, needle shaped and hopper crystals were obtained. These crystals were also grown by doping impurities such as copper and iron. Kinetics of growth parameters was investigated. Structural analysis was carried out by using X-ray powder diffraction method. Microtopographical study of the habit faces, such as prismatic and pyramidal, of as grown crystals was carried out. Some surface structures are reported. These crystals were etched by various etchants and appropriate etchant is reported.

Synthesis of single crystals of calcium iodate by gel method is described. Fairly transparent crystals of reasonably large size with different habits obtained here are illustrated. Crystals grown are identified and characterized by electron microprobe, chemical, X-ray, thermogravimetric and infra-red analysis. Es wird die Darstellung von Calciumjodatkristallen nach der Gelmethode beschrieben. Gut durchsichtige Kristalle von ziemlicher Grose mit verschiedener Ausbildung werden vorgestellt, identifiziert und charakterisiert mit Hilfe der Elektronenmikrosonde, der chemischen, Rontgen-, thermogravimetrischen und IR-Analyse.