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Arrested reactive milling is used to prepare a composite thermite powder combining magnesium metal with calcium iodate, Ca(IO3)2. Upon ignition, this material generates iodine, a biocidal species capable of effective inactivation of aerosolized microorganisms. The prepared material is metal-rich with a fuel/oxidizer ratio of 4. It contains 29 wt% of iodine. The material is a micron-sized powder with each particle having a magnesium matrix and nanosized inclusions of calcium oxide. A similar composite with a stoichiometric ratio of fuel to oxidizer is found to be unstable in air. The prepared metal-rich composite was characterized using thermo-gravimetric analysis, ignition experiments using an electrically heated filament, and particle combustion experiments in both air and the combustion products of an air-acetylene flame. The powder was found to readily release iodine upon heating. It ignited in two distinct stages, with the first, low-temperature ignition prompted by iodine release, and second stage ignition caused by reaction of any remaining magnesium. In an air-acetylene flame, the powder particles burned in two distinct stages, unlike other similar materials. In air, only one combustion stage was distinguished. Combustion of the prepared powders in air occurs much faster than in the products of the air-acetylene flame; burn rates of the prepared composite powders in both air and products of air-acetylene flame are slightly lower than those of pure magnesium burning in the same environments.

In this paper, in-situ coagulation of 0.9Al2O3–0.1TiO2 suspension and microwave dielectric properties of 0.9Al2O3–0.1TiO2 ceramics prepared by a novel direct coagulation casting via high valence counter ions (DCC-HVCI) method were proposed. The 0.9Al2O3–0.1TiO2 suspension could be coagulated via controlled release of calcium ions from calcium iodate at an elevated temperature. The influence of tri-ammonium citrate (TAC) content, solid loading, and calcium iodate content on the rheological properties of the suspension was investigated. In addition, the influence of coagulation temperature on coagulation time and properties of green bodies was also studied. It was found that the stable 0.9Al2O3–0.1TiO2 suspension could be successfully prepared by adding 0.3 wt% TAC and adjusting pH value to 10–12 at room temperature. 0.9Al2O3–0.1TiO2 green bodies with uniform microstructures were coagulated by adding 8.0 g/L calcium iodate after treating at 70 °C for 1 h. 0.9Al2O3–0.1TiO2 ceramics, sintered at 1500 for 4 h and annealed at 1100°C for 5 h, showed °Cuniform microstructures with density of 3.62±0.02 g/cm3. The microwave dielectric properties of 0.9Al2O3–0.1TiO2 ceramics prepared by DCC-HVCI method were: εr = 11.26±0.06, Q×f = 11569±629 GHz, τ f = 0.93±0.60 ppm/°C. The DCC-HVCI method is a novel and promising route without binder removal process to prepare complex-shaped microwave dielectric ceramics with uniform microstructures and good microwave dielectric properties.

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.

A novel direct coagulation casting via controlled release of high valence counter ions (DCC-HVCI) method was applied to prepare the alumina fiber-reinforced silica matrix composites with improved mechanical properties. In this method, the silica suspension could be rapidly coagulated via controlled release of calcium ions from calcium iodate and pH shift by hydrolysis of glycerol diacetate (GDA) at an elevated temperature. The influence of tetramethylammonium hydroxide (TMAOH) dispersant amount, volume fraction and calcium iodate concentration on the rheological properties of suspensions was investigated. Additionally, the effect of alumina fiber contents on the mechanical properties of alumina fiber-reinforced silica matrix composites was studied systematically. It was found that the stable suspension of 50 vol% solid loading could be prepared by adding 2.5 wt% TMAOH at room temperature. The addition of 0–15 wt% alumina fibers had no obvious effect on the viscosity of the silica suspension. The controlled coagulation of the suspension could be achieved by adding 6.5 g L −1 calcium iodate and 1.0 wt% GDA after treating at 70 °C for 30 min. Compressive strength of green bodies with homogeneous microstructure was in the range of 2.1–3.1 MPa. Due to the fiber pull-out and fracture behaviors, the mechanical properties of alumina fiber-reinforced composites improved remarkably. The flexural strength of the composite with 10 wt% alumina fibers sintered at 1350 °C was about 7 times of that without fibers. The results indicate that this approach could provide a promising route to prepare complex-shaped fiber-reinforced ceramic matrix composites with uniform microstructure and high mechanical properties.

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.

Rapid in-situ solidification of SiO 2 suspension under the joint action of releasing calcium ions and shifting pH has been proposed. When the suspension was heated up to 60 ℃, decomposition of calcium iodate which released calcium ions, as well as hydrolysis of diacetate (GDA) which shifted the pH toward the isoelectric point, both contributed to the solidification of suspension. The controlled coagulation of SiO 2 suspension could be realized via controlled release of high valence counter ions and pH shift at 60 ℃ within 30 min, which could considerably shorten the coagulation time compared with present reported results (1–3 h). Green body prepared by heating the SiO 2 suspension with 6.5 g L −1 calcium iodate and 2.0 vol% GDA at 60 ℃ for 30 min shows uniform microstructure with compressive strength of close to 0.3 MPa. SiO 2 ceramics sintered at 1275 ℃ for 3 h possess homogeneous microstructure with bulk density of 2.06 g cm −3 and flexural strength of 40.3 MPa.

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.

Aim: Objective of this study was to investigate the effect of different levels of iodine supplementation on iodine content of eggs in laying hens. Materials and Methods: In the experiment, 135 laying hens (White Leghorn) of 55 weeks age were randomly distributed to 5 dietary treatments; each group contained 27 laying hens distributed in three replicates of 9 birds each. Diet T1 was control basal layer diet without iodine enrichment in which iodine content (I2) was as per NRC recommendation. Basal diets were supplemented with calcium iodate (Ca (IO3)2) at 5, 10, 15 and 20 mg/kg in T2, T3, T4 and T5 groups, respectively. The iodine content in the calcium iodate is 65.21%, therefore, the diets T2, T3, T4 and T5 contained 3.25, 6.50, 9.75 and 13.0 ppm iodine, respectively. The laying hens were fed the respective experimental diets ad libitum during the experimental period of 10-week. The iodine content of egg yolk and albumen was analyzed at the end of 5th and 10th week of the experiment. Economics of feeding for the production of iodine enriched egg was calculated at the end of the experiment. Results: Increasing iodine levels in diet of hens from 0.45 to 13.0 ppm significantly increased egg iodine concentration, the highest concentration of egg iodine was observed in the group fed diet supplemented with 13.0 ppm iodine followed by those fed 9.75, 6.50, 3.25 and 0.45 ppm iodine in diet. There was no significant difference in the iodine levels of unboiled versus boiled eggs. Therefore, the consumers are ensured to receive the optimal levels of iodine from boiled iodine-enriched eggs. Among different diets, minimum and significantly lower feeding cost (Rs. per dozen or per kg eggs) was noticed in hens allotted T3 diet (6.50 ppm I2). However, feeding cost of hens receiving 3.25 and 9.25 ppm I2 was statistically (p

Calcium iodate is an inorganic source of calcium and iodate ions which has not yet been widely considered by researchers. In this paper, we used a straightforward, cost-effective, and robust study for synthesis of calcium iodate/gelatin hybrid composite particles at ambient temperature. We conducted single diffusion procedure of calcium ions in gelatin hydrogel at pH ​= ​5, 7 and 9 for three weeks. Feather-like calcium iodate/gelatin composite particles were later observed, and we characterized them using Fourier transform infrared spectroscopy, scanning electron microscopy, optical microscopy, X-ray diffraction, thermal gravimetric analysis, reflectance spectroscopy and bacteriological culture plate. Spectroscopy methods confirmed successful synthesis of calcium iodate/gelatin composite particles. Microscopic observations showed formation of two primary composite morphologies including plate-shaped and feather-like particles. Our research proved that gelatin hydrogel is not only able to change the morphology and thermal properties of calcium iodate, but it also lowers the reflectance values of final composite particles toward the visible region. Interestingly, we found antibacterial properties in particles which is promising for tissue engineering applications.

The objective of the study was to evaluate the influence of high iodine intake in ewes on haematological and biochemical parameters of the blood of ewes and their lambs. Twelve pregnant ewes of the Sumava sheep breed and their newborn lambs were included in the experiment. Control group (A) consisted of 6 ewes with 7 lambs and experimental group (B) comprised 6 ewes with 6 lambs. The feed ration was enriched with calcium iodate by addition of 3 and 5 mg/kg in group A and group B, respectively. The studied parameters in ewes and lambs were haematocrit value, red blood cell count and haemoglobin concentration in blood, concentration of urea and total proteins, and alkaline phosphatase activity in blood plasma. No differences were found out in haematocrit value, red blood cell count, concentration of haemoglobin and total proteins between groups of ewes A and B with their lambs. Urea concentration and alkaline phosphatase activity were higher in ewes of group B and their lambs during the entire experimental period. An increase in the values of urea and alkaline phosphatase in the group of ewes and lambs with higher iodine intake indicates a potential risk of high iodine intake associated with changes in the thyroid activity in ewes and their lambs.

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.

The aim of the present study was to investigate the impact of various feed iodine supplementations up to the permitted maximum level in the EU, the effect of applying rapeseed meal (RSM) compared to a glucosinolate (GSL) free ration and the impact of two different iodine species (iodide, iodate) on milk, urinary, faecal and blood serum iodine as well as on T3 and T4 levels of blood. The results of the milk iodine are not completely shown but partly discussed in this paper. The study was conducted with 32 dairy cows, divided into 4 groups with 8 animals each. In two groups the cows were fed distillers dried grains with solubles (DDGS) as main protein source (16.5% of ration DM), in the other groups rapeseed meal (3.5 mmol GSL/kg) was applied. In each case half of the animals received feed with iodine in the form of potassium iodide, the other half as calcium iodate. Iodine supplementations of 0, 0.5, 1, 2, 3, 4 and 5 mg/kg DM were tested in consecutive periods of 21 days each. The supplementary iodine increased iodine contents of serum, urine and faeces. RSM application resulted in consistently higher iodine contents in the mentioned matrices just displaying significant differences at high supplementation levels. When feeding DDGS, at high iodine supplementations iodide caused higher serum and faecal iodine than iodate. Besides, the iodine species showed no consistent impact on the tested parameters. At the highest tested iodine supplementation (5 mg/kg DM) in the experimental groups (DDGS/iodide, DDGS/iodate, RSM/iodide, RSM/iodate) the iodine concentration of serum amounted to 234, 157, 334 and 361 µg/l, of urine to 1134, 1020, 2341 and 2513 µg/l and of faeces to 673, 354, 715 and 790 µg/kg fresh matter. At the same supplementation level T4 was significantly lowered. No impact was shown for the RSM application and the iodine species on T3 and T4. The results of the present study indicate that high iodine intakes not only cause strong increases in milk and urinary iodine but also lead to a considerable rise of iodine excretion via faeces. RSM in feed causes a shift of iodine normally excreted via milk to an excretion via urine and faeces accompanied by higher serum iodine.

Supplementation of animal feed with iodine influences the iodine content of milk and therefore, in addition to salt iodination, provides another possibility for improving the human iodine supply. On the other hand, excessive iodine intake by humans through drinking milk must be avoided. Furthermore, the iodine content of milk varies, depending on the presence of iodine antagonists in feed (e.g., glucosinolates in rapeseed) and the applied iodine species. This study evaluated the impact of various feed iodine supplementation levels up to the permitted maximum level, the effect of applying rapeseed compared with a glucosinolate-free ration, and the impact of 2 different iodine species on the iodine content of milk. A total of 32 dairy cows were divided into 4 groups with 8 animals each. Two groups received distillers dried grains with solubles (DDGS) as the protein source, and the others received rapeseed meal (RSM, 16.5% of total diet). In each case, half the animals received feed supplemented with iodine in the form of potassium iodide, and the other half received feed supplemented with iodine in the form of calcium iodate. Iodine supplementation levels of 0, 0.5, 1, 2, 3, 4, and 5 mg/kg of dry matter (DM) were tested in consecutive periods of 21 d each. The milk iodine concentration increased with increasing iodine supplementation of the feed. Rapeseed meal in the ration (0.58 mmol of glucosinolates/kg of diet DM) diminished the milk iodine concentration by up to one-half to one-third of the concentration achieved by DDGS. At iodine supplementation levels of 2 mg/kg of DM and higher, the differences were significant. The application of iodate predominantly resulted in higher milk iodine concentrations compared with iodide, but not significantly in any period. At the highest tested iodine supplementation (5 mg/kg of DM), the milk iodine concentration increased up to 1,464 (iodide) and 1,578 microg/kg (iodate) when feeding DDGS and up to 718 (iodide) and 620 microg/kg (iodate) in the RSM groups. The carry over of iodine from feed into milk amounted to 30 to 56% when using DDGS, and 11 to 25% when using RSM. The maximum level of iodine currently allowed in the feed of dairy cows in Europe could lead to high milk iodine concentrations. As a result, the Tolerable Upper Intake Level in human nutrition could be exceeded. Therefore, this maximum level needs to be reevaluated. In addition to iodine supplementation, the application of RSM in the ration must be considered when estimating the iodine content of milk.

A novel gel tape casting process has been developed by introducing sodium alginate into a conventional aqueous tape casting slurry. The process makes use of a binder system consisting of 1 wt-% sodium alginate and 20 vol.-% styrene acrylic latex to prepare the tape casting slurry. Sodium alginate can react with calcium iodate to form a three-dimensional network at room temperature, and with the ceramic particles held in this three-dimensional network, the slurry can be consolidated to form green tapes. This allows the need for the special drying procedure that is usually a critical step in tape casting to be avoided. Styrene acrylic latex was used to improve the flexibility of the green tapes. Compared with tapes obtained by conventional aqueous tape casting, more homogeneous microstructure was obtained by this process.

In the present work, we studied the addition of sodium alginate, a natural innoxious polymer, to coagulate alumina slurry in the fabrication of an Al2O3 green body. Calcium iodate was added into the alumina suspension that was dispersed in a sodium alginate solution. The slurry was stable at room temperature but it solidified with increasing temperature. A slurry of 50 vol.% alumina ceramic powder, 1 wt.% calcium iodate and 1 wt.% sodium alginate solidified after being heated at 60 °C for 1 h. In addition to this process, a chelator was used to control the gelation behavior. Associated with the effect of the chelator, the consolidation reaction rate was delayed to longer than 30 min. The gelling properties of the sodium alginate solution and the resultant alumina slurry were analyzed. The rheological behavior of the slurry was examined. Appropriate forming processes were determined. Near-net-shaped green bodies were produced. The resultant green body has uniform structure and smooth surface, and the bonding strength is as high as 8.0 MPa.

Single crystals of calcium iodate and barium iodate were grown by simple gel technique by single diffusion method. The optimum conditions were established by varying various parameters such as pH of gel solution, gel concentration, gel setting time, concentration of the reactants etc. Crystals having different morphologies and habits were obtained. Prismatic, dendritic crystals of barium iodate and prismatic, needle shaped, hopper crystals of calcium iodate were obtained. Some of them were transparent, some transluscent, and few others were opaque. Both the crystals were studied using XRD, FT-IR, and thermal analysis. The crystals were doped by iron impurity. The effect of doping was studied using IR spectroscopy and thermal analysis.

The aim of this work was to assess the long-term effect of excessive iodine intake on thyroid activity and selected immunological, haematological and biochemical parameters in blood of ewes and their lambs. The experiment was conducted from August 2009 to February 2010 in an experimental barn of Faculty of Agriculture, University of South Bohemia in České Budějovice. Into the experiment were used Šumava sheep breed ewes and their born lambs. Group A (control) consisted of 6 ewes after lambing was extended to 7 born lambs, group B (experimental) 6 of 6 ewes and lambs. Lambs were put into the experiment from the 1st to the 60th day after birth and received iodine in the milk of their mothers. Iodine supplementation to the diet of ewes was launched during the first to second months of pregnancy and finished 60 days after birth. During the experiment, a group of ewes A received 3,1 and group B 5,1 mg iodine per kg of dietary dry matter in the form of calcium iodate. During the experiment was regularly collected blood of ewes (before lambing and 1st, 10th, 30th and 60th day after birth) and lambs (1st, 3rd, 10th, 30th and 60th day after birth) to determine the concentration of thyroid stimulating hormone and immunoglobulin G (ELISA) in blood serum, thyroid hormones (RIA), total protein, urea and alkaline phosphatase activity in the blood plasma (biochemical analyser), the content of haemoglobin, white blood cell´s and red blood cell´s counts and haematocrit values in blood (haematological analyser), percentage of albumin, -1-globulins, -2-globulins, -globulins, and -globulins in blood serum (electrophoresis) and the content of iodine in the blood plasma, urine and milk of ewes (colorimetric method Sandell-Kolthoff). During the experiment were not observed in ewes and lambs clinical symptoms associated with an excessive intake of iodine. In experimental group of ewes with iodine intake 5,1 mg/kg of dietary dry matter were found higher values of thyroid stimulating hormone, lower values of free triiodothyronine, free thyroxine, IgG, white blood cells, -1-globulins, -2-globulin and -globulin, significantly lower values of -globulins after parturition, significantly higher values of urea and alkaline phosphatase activity. The iodine content in blood plasma, milk and urine of ewes is increased in direct proportion to its concentration in diet. Lambs of mothers with iodine intake of 5,1 mg/kg of dietary dry matter were significantly higher values of thyroid stimulating hormone from the 10th day after birth, significantly lower values of free triiodothyronine and free thyroxine first day after birth, immunoglobulin G and -globulins in 30th day after birth, lower (statistically significant in middle samples) values of total protein and white blood cells, higher values of urea and alkaline phosphatase activity. The weight gains of lambs were not significantly affected by iodine supplementation. These results in ewes with iodine intake of 5,1 mg/kg dietary dry matter and especially their lambs drawn to risk of reduce the activity of the thyroid gland and the negative impact of parameters of humoral immunity, mainly IgG and -globulins.

Gel-casting has been widely studied for the last decade [1–5]. In this process, a slurry made from ceramic powder and a water-based monomer solution is poured into a mold, polymerized in situ. The gelled part is removed from the mold while still wet, and then is dried and fired. The dried green body is strong enough to be machined. However, the process is not perfect in that the polymerization of monomers is difficult to control in the ceramic suspension. Reductive agents usually restrain the free-radical polymerization of commonly used acrylamide. In addition, acrylamide is highly toxic. Therefore, new gelcasting process with a reduced toxicity have been investigated [6–8]. In fact, many polymer solutions can gelate under suitable conditions [9, 10], such as agarose, gelatin and sodium algaecide. Some of them have been employed in food industry [10]. When the polymer is dissolved in solvents, the molecular chains attract each other to form a three-dimensional network by hydrogen bonds or Van der Walls forces. The gelling property of agar has been used in the water-based injection molding [11]. Recently, we have reported that ceramic suspension was gelled to green body using gelatin and agarose [7, 12]. However, the suspension containing agarose has to be heated up to 80 ◦C before casting, which easily results in water vaporization. In addition, both agarose and gelatin are expensive when they are employed in industry. Alginate is a type of gelling polysaccharide, which can be dissolved in water at room temperature and then gelled after casting by cross-linking with divalent metal ions at increased temperature. Like all cationexchangers the selectivity and strength of binding depend on both the nature of the cation and the properties of the polymer. Divalent and polyvalent cations and bound strongly by all types of alginate and effectively cross-link the polysaccharide to form a gel matrix. However, regions of polysaccharide form particularly strong chelation complexes with divalent cations, especially the calcium ion [13]. The mechanism of crosslinking in alginate gels can be considered in terms of an “egg-box” model involving cooperative binding of calcium ions between aligned polyguluronate ribbons as shown in Fig. 1 [10, 14]. The buckled chains of polysaccharide form a structure akin to the cross-section of an egg-box in which the calcium ions are the “eggs”. The binding of the calcium ion is strong because, in addition to the ionic binding to the carboxyl groups, various ring and hydroxyl oxygen atoms are able to chelate the cations. Although there are many salts containing calcium ion, such as CaCl2 · 4H2O, CaC2O4, Ca(C6H11O7)2, Ca(IO3)2 · 6H2O, which can react with alginate and crosses link together. However, it is generally very difficult to control the reaction rate for most of them. This makes it impossible to complete casting processing at certain period. Therefore, the divalent salts with a controlled reaction rate with alginate have to be considered. In other words, divalent cation concentration released from the salt can be adjusted with temperature or time. Examining the solubility of above salt substances at different temperatures, we found that Ca(IO3)2 · 6H2O is good for gelcasting processing because they have a lower solubility (0.17 wt%) at room temperature and a high solubility (1.38 wt%) at increased temperature of 60 ◦C. So Ca(IO3)2 · 6H2O was chosen in this study. In the present paper, the gelling properties of sodium alginate solution and resulting suspension with ceramic powder were investigated. The rheological behavior was examined. Near-net-shaped green bodies with different shapes were produced by the novel forming processing. Sodium alginate used is a commercially available fine powder with white color. Sodium alginate solutions with different concentration were prepared by stirring in deionized water at room temperature. The apparent viscosity of the solution was examined by a rotary viscometer (Model NXS-11, Chendu Instrument Plant, China). Fig. 2 shows the results of rheological properties influenced by the alginate concentration. For lower concentrations of sodium alginate of 0.5 and 1.0 wt%, the flow properties are almost Newtonian mold, and shear-thinning characteristics of alginates are obvious at high concentrations. These results are in good agreement with other reports [10]. It should be noted that the viscosity of the solution with 3 wt% alginate had a maximum value at the shear rate of about 35 s−1. This can be explained from the competition between promptly chain association and breaking down by shear. To examine the controlled gelling process of calcium and alginate, 1 wt% calcium iodate was dispersed in the 3 wt% alginate solution by stirring, and then moved the bake containing alginate suspension to water bath at 60 ◦C. Fig. 3 illustrates that the viscosity varies with time for the system. As a comparison, viscosity curves without calcium iodate was included in same figure. At the initial period, viscosity increases very slowly from a

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.

Thermal and calorimetric studies were carried out on M(IO3)2·6H2O and M(IO3)2·6D2O forM2+=Ca2+ and Sr2+, using DTA and DSC methods. The thermal behaviour of the ordinary and deuterated hydrates is outlined and the differences observed between them are discussed. The enthalpies of the phase transitions were determined. The ΔH f o for Ca(IO3)2·6H2O, Ca(IO3)2·6H2O(D2O) and Sr(IO3)2·6H2O(D2O) were calculated from the ΔHdeh data and comments are made on the isotope effect observed.

Thermal and calorimetric investigations were carried out on M(IO 3 ) 2 ·H 2 O and M(IO 3 ) 2 ·D 2 O (M 2+ = Ca 2+ , Sr 2+ , Ba 2+ ) using DTA and DSC. We investigate the thermal behaviour of the ordinary and deuterated monohydrates, and discuss the differences observed between them. The enthalpy of the dehydration processes is determined. The Δ H deh XXX , data were used to calculate the value of Δ H f XXX for the investigated monohydrates and monodeuterates. Comments are presented in relation to the isotope effect with regard to Δ H deh XXX and T max,deh .

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.

A total of 135 layers of 55 weeks age were randomly distributed into 5 dietary treatments with 3 replicates having 9 birds each. Layers of group T1 (Control) were fed basal diet. Diets of layers in group T2, T3, T4 and T5 were same as T1 except that in these diets iodine was supplemented as calcium iodate in such a way that respective diets contained 3.25, 6.50, 9.75 and 13.0 mgI/kg feed. Total experimental period lasted for ten weeks. Weight gain (g/hen), feed intake (g/hen/day), cumulative feed intake (kg/hen) and hen-day egg production (%) was comparable in groups T1, T2 and T3, however, lower (P

KI and KIO3 are the commonly used prophylactic drugs for the protection of thyroid glands against radioiodine. In this study, we have demonstrated the use of another iodine containing salt, calcium iodate [Ca(IO3)2], as an effective blocker of radioiodine uptake by the thyroid gland in rats. Ca(IO3)2 is permitted by the FDA as a food additive and is "generally regarded as safe" (GRAS, CFR No.1206). We have also compared the efficacy of Ca(IO3)2 with KIO3 in blocking thyroidal uptake of radioiodine, which could be important considering the better shelf life of Ca(IO3)2. Laboratory rats were administered 131I and stable iodide in the form of KIO3 or Ca(IO3)2 was given orally, 2 h after the administration of 131I. All the animals were monitored for whole body retention (WBR) of 131I, at 24 h and further for 14 d. The results of the present study provide us with evidence that Ca(IO3)2 can serve as another promising radioiodine blocker, and is as equipotent as KI/KIO3 in protecting the thyroid gland. We have not found any studies that examined the property of Ca(IO3)2 in blocking radioiodine uptake by the thyroid gland and the present study is an attempt in this direction.

Simple gel technique was used to grow single crystals of calcium iodate, monohydrate, by single diffusion method. For the growth of crystals, the optimum conditions were established. Crystals having different morphologies like prismatic and prismatic pyramidal were obtained. Few crystals were opaque, some were translucent and some good quality transparent crystals were obtained. Doping of Cu+2 and Fe+3 was done, to study the effect on structure, thermal and nonlinear optical properties. Cell parameters were obtained from the X-ray diffractograms. Structural analysis was done by using FT-IR spectroscopy. TGA and DTA techniques were used to carry out thermal analysis. Nonlinear optical properties were studied using SHG measurements.

Publisher Summary Iodine is an essential micromineral for all animal species, including humans. It occurs in plant tissues predominantly as inorganic iodide and is readily absorbed in this form from all segments of the intestinal tract. Few definitive studies of iodine bioavailability have been done since 1973. The current information is primarily from the work of Miller and his associates at the University of Tennessee with dairy cattle. Early studies have shown that either sodium iodide (NaI) or potassium iodide (KI), as supplemental sources of iodine, were effective in maintaining normal thyroid weights in rats fed with goitrogenic diets. Several researchers have used uptake of stable or radioactive iodine by the thyroid or other tissue as an indication of bioavailability of an iodine source. Injectable forms of iodized oils, as well as iodized oils administered orally, have served as effective sources of supplemental iodine in the reduction of endemic goiter in human populations. Iodine is unique in that stability of the carrier compound is of great importance. Goitrogenic substances present in feed or food are the most important factors influencing iodine bioavailability. Perchlorates and rubidium salts were known to interfere with iodine uptake by the thyroid. Sodium iodide, potassium iodide, and thylenediamine dihydriodide are well utilized by animals as sources of iodine. Calcium iodate and pemacalcium orthoperiodate are also of high bioavailability and have been shown to have greater physical stability. Potassium iodide or sodium iodide has usually served as the reference standard when comparative studies were conducted.

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.

A new four-step thermochemical cycle based on calcium and iodine is proposed for the decomposition of water. The chemical reactions comprising the cycle are: the redox reaction of iodine with calcium hydroxide; the thermal decomposition of calcium iodate; the hydrolysis of calcium iodide; and the thermal decomposition of hydrogen iodide. Experimental verification of each of these reactions and an evaluation of the thermal efficiency of the process based on the material and energy balances for a proposed flow sheet are also presented.

The dimesoperiodates of the alkaline earths, M 2 I 2 O 9 . n H 2 O (Ca, n = 8; Sr and Ba, n = 3) on thermolysis form hexavalent iodates, MIO 4 as intermediate products which with increasing temperature decompose to their orthoperiodates, M 5 (10 6 ) 2 via presumably the formation of M 2 I 2 O 7 type compounds. MIO 4 compounds can be made from dimesoperiodates by heating at 220–240° for 2 hr. The hexavalent state of iodine in MIO 4 has been verified by chemical analysis, magnetic moment measurement and EPR spectra. These compounds undergo hydrolytic decomposition to metal iodate and hydroxide accompanied by the evolution of oxygen. Anhydrous barium iodate prior to its decomposition undergoes a phase transition, this change is less defined in the strontium compound and is not observed in calcium iodate. The energy of activation, the order of reaction and the enthalpy change for the conversion of the iodates to the orthoperiodates have been evaluated by non-isothermal kinetic study.

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.

The solubility of Ca(IO 3 ) 2 in molten equimolar (K,Na)NO 3 containing various amounts of Ca(NO 3 ) 2 was measured in the temperature range 523–613 K. The shape of the solubility curves can be explained by equilibria between Ca(IO 3 ) 2 (s), CaIO 3 + , IO 3 − and Ca 2+ in the entire temperature and composition range studied. Stability constants for CaIO 3 + and solubility products were determined at five temperatures, and Δ H ° and Δ S ° for the corresponding processes were estimated. CaIO 3 + is a rather weak complex and the ΔH ° 1 and - TΔS ° 1 contribute approximately the same amounts to ΔG 1 ° for the association. It is concluded that ΔH 1 ° for this process might be mainly caused by changes in electrostatic energies between nearest neighbour hard-sphere ions.

The nutritional availability of iodine from calcium iodate, pentacalcium orthoperiodate (PCOP), and sodium iodide was compared using six near-term pregnant cows. Nine days before expected parturition, three were orally dosed with 2mCi 125 I-labeled calcium iodate and three orally with 2mCi 125 -labeled pentacalcium orthoperiodate. Each animal was orally given 2mCi Na 131 I simultaneously with the 125 I doses. One animal from each group was killed seven days after dosing and four were allowed to calve normally. Blood plasma radioiodine concentrations, thyroid uptake, and urinary and fecal radioiodine excretions were comparable for each of the iodine compounds during seven days after dosing. Calcium iodate and pentacalcium orthoperiodate were equally available as iodide for transfer to the unborn fetus as indicated by equal 125 I and 131 I concentrations in slaughter samples including maternal and fetal thyroids, abomasal content, placental fluids, cotyledons, and fetal bladder content and bile. Thyroid and plasma 125 I levels equaled corresponding 131 I values for four cows and calves during six days following parturition. It was concluded that calcium iodate and pentacalcium orthoperiodate are adequate supplemental iodine sources for cattle.

Measurements are reported of the solubilities of calcium iodate and copper iodate in buffered solutions of sodium malonate and potassium hydrogen phthalate. Thermodynamic association constants are determined for the formation of the species CaPh, CuPh, CuHPh + at 25°, 30°, 35°, 40° and 45°C and of the species Ca Mal , Cu Mal , CuH Mal + at 25°, 30°, 35° and 40°C. Δ H °, Δ G °, δ S ° are calculated for the formation reactions of these complexes and hydration entropies of the complexes are also derived.

A new simple, rapid and accurate amplification micro method for fluoride determination is described. It is based on the reaction between the sparingly soluble calcium iodate and the fluoride ion. After adding isopropyl alcohol to the solution, so that its final concentration is 65%, and filtering, an equivalent amount of the iodate is obtained. The latter is titrated iodometrically resulting in a six-fold amplification of the titre. The method is reproducible over a range from 0.4–8 mg fluoride ion. The mean recovery is 99.69%, after applying a correction factor due to potassium iodate solubility.

Etude du CuCl 2 dissous dans une solution saturee de CaCl 2 . Effet important de la nature du milieu chlorure

Measurements are reported of the solubilities of calcium iodate and copper iodate in buffered solutions of sodium glycollate and of calcium iodate in mandelate buffers. Thermodynamic association constants are derived for the formation of the ion-pairs Ca GL + and Gu GL + , at 25, 30, 35, 40 and 45°C and of the species Ca Man + at 25, 30, 35, 40 and 45°C where GL = glycollate, Man = Mandelate. ΔH°, ΔG° and ΔS° are evaluated for the formation reactions of these species. The hydration entropies ΔS hyd . ( MX ) + of these complexes are also calculated.

Measurements are reported of the solubilities of calcium iodate and copper iodate in buffered solutions of sodium malate. The thermodynamic association constants are determined for the formation of the species CaMal at 25°, 30°, 35° and 40°C and of the species CuMal, CuHMal + at 25°, 30° and 45°C. Thermodynamic functions ΔH °, ΔG °, ΔS ° are derived from the association reactions of these complexes and hydration entropies of the species have also been calculated.

UNLESS properly protected, potassium iodide loses iodine when mixed with other minerals of the trace mineral mix or when subjected to adverse storage conditions of moisture, heat and sunlight. In order to overcome the problem of stability, many types of iodine compounds have been studied, one of which, the iodates, has proved to be very satisfactory without any protective coating. However, since availability is even more important than stability, the following experiment with chickens was undertaken to evaluate calcium iodate as a goiter-preventing agent. The iodates are not new as chemical compounds or as therapeutic agents in medicine. Their pharmocological action in animals was studied more than eighty years ago by Melsens (1871), indicating that the iodate is converted to the iodide in vivo and absorbed as such by the thyroid gland. Recently, the thyroid uptake of iodine from iodate in man was measured by Murray and Pochin (1951) with . . .