The Experts below are selected from a list of 93 Experts worldwide ranked by ideXlab platform
Jinlong Yang - One of the best experts on this subject based on the ideXlab platform.
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direct coagulation casting of alumina suspension by high valence counter ions using ca io3 2 as coagulating agent
Journal of the American Ceramic Society, 2012Co-Authors: Jie Xu, Xiaoqing Xi, Hexin Li, Fei Qi, Jinlong YangAbstract: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.
Yusheng Shi - One of the best experts on this subject based on the ideXlab platform.
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Study of 0.9Al2O3–0.1TiO2 ceramics prepared by a novel DCC-HVCI method
SpringerOpen, 2018Co-Authors: Huan Xiao, Mengyue Liu, Lijin Cheng, Ying Chen, Yusheng ShiAbstract:Abstract 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
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rapid in situ solidification of sio2 suspension by direct coagulation casting via controlled release of high valence counter ions from Calcium Iodate and ph shift
Ceramics International, 2017Co-Authors: Annan Chen, Mengyue Liu, Lijin Cheng, Jingyan Chen, Huan Xiao, Xiaoyan Zhang, Yusheng ShiAbstract:Abstract 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.
Efsa Panel On Additives And Products Or Substances Used In Animal Feed - One of the best experts on this subject based on the ideXlab platform.
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Scientific Opinion on the safety and efficacy of iodine compounds (E2) as feed additives for all animal species: Calcium Iodate anhydrous, based on a dossier submitted by Calibre Europe SPRL/BVBA
Wiley, 2013Co-Authors: Efsa Panel On Additives And Products Or Substances Used In Animal FeedAbstract:Calcium Iodate anhydrous is considered a safe source of iodine for all animal species/categories when used up to the currently authorised maximum content of total iodine in complete feed, with the exception of horses and dogs, for which maximum tolerated levels are 3 and 4 mg I/kg complete feed, respectively. The limited data available on iodine tolerance in cats support a provisional tolerated level of 5 mg I/kg complete feed. Exposure of consumers was calculated in two scenarios applying the currently authorised maximum iodine contents in feed and reduced contents. The iodine content of food of animal origin, if produced taking account of the currently authorised maximum content of iodine in feed, would represent a substantial risk to high consumers. The risk would originate primarily from the consumption of milk and to a minor extent from eggs. The UL for adults (600 µg/day) and for toddlers (200 µg/day) would be exceeded by a factor of 2 and 4, respectively. If the authorised maximum iodine concentrations in feed for dairy cows and laying hens were reduced to 2 and 3 mg I/kg feed, respectively, the exposure of adult consumers would be below the UL. However, iodine intake in high-consuming toddlers would remain above the UL (1.6-fold). Calcium Iodate is considered as irritant to the eye, skin and respiratory tract, and a dermal sensitiser. The exposure by inhalation should be avoided. The use of Calcium Iodate in animal nutrition is not expected to pose a risk to the environment. Calcium Iodate is efficacious to meet animal iodine requirements. The FEEDAP Panel recommends that the maximum iodine contents in complete feed be reduced as follows: dairy cows and minor dairy ruminants, 2 mg I/kg; laying hens, 3 mg I/kg; horses, 3 mg I/kg; dogs, 4 mg I/kg; cats, 5 mg I/kg
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Scientific Opinion on the safety and efficacy of Iodine compounds (E2) as feed additives for all species: Calcium Iodate anhydrous (coated granulated preparation), based on a dossier submitted by Doxal Italia S.p.A.
Wiley, 2013Co-Authors: Efsa Panel On Additives And Products Or Substances Used In Animal FeedAbstract:Calcium Iodate anhydrous is considered a safe source of iodine for all animal species/categories when used up to the currently authorised maximum content of total iodine in feed, with the exception of horses and dogs, for which maximum tolerated levels are 3 and 4 mg I/kg complete feed, respectively. The limited data available on iodine tolerance in cats support a provisional tolerated level of 5 mg I/kg complete feed. Consumers exposure was calculated in two scenarios applying the currently authorised maximum iodine contents in feed and reduced contents. The iodine content of food of animal origin, if produced taking account of the currently authorised maximum iodine content in feed, would represent a substantial risk to high consumers. The risk would originate primarily from milk consumption and to a minor extent from eggs. The UL for adults (600 µg/day) and for toddlers (200 µg/day) would be exceeded by a factor of 2 and 4, respectively. If the authorised maximum iodine concentrations for dairy cows and laying hens were reduced to 2 and 3 mg I/kg feed, respectively, the exposure of adult consumers would be below the UL. However, iodine intake in high-consuming toddlers would remain above the UL (1.6-fold). The formulated additive could pose a risk by inhalation to users. The preparation is non irritant to skin and eyes but may be a dermal sensitiser; coating may prevent the contact of the active substance to skin and eyes. The use of Calcium Iodate in animal nutrition is not expected to pose a risk to the environment. Calcium Iodate is efficacious to meet iodine requirements. The FEEDAP Panel recommends the maximum iodine contents in complete feed be reduced: dairy cows/minor dairy ruminants, 2 mg I/kg; laying hens, 3 mg I/kg; horses, 3 mg I/kg; dogs, 4 mg I/kg; cats, 5 mg I/kg
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Scientific Opinion on the safety and efficacy of iodine compounds (E2) as feed additives for all species: Calcium Iodate anhydrous and potassium iodide, based on a dossier submitted by HELM AG
Wiley, 2013Co-Authors: Efsa Panel On Additives And Products Or Substances Used In Animal FeedAbstract:Calcium Iodate anhydrous and potassium iodide are considered safe sources of iodine for all animal species/categories when used up to the currently authorised maximum content of total iodine in complete feed, with the exception of horses and dogs, for which maximum tolerated levels are 3 and 4 mg I/kg complete feed, respectively. The limited data available on iodine tolerance in cats support a provisional tolerated level of 5 mg I/kg complete feed. Exposure of consumers was calculated in two scenarios applying the currently authorised maximum iodine contents in feed and reduced contents. The iodine content of food of animal origin, if produced taking account of the currently authorised maximum content of iodine in feed, would represent a substantial risk to high consumers. The risk would originate primarily from the consumption of milk and to a minor extent from eggs. The UL for adults (600 µg/day) and for toddlers (200 µg/day) would be exceeded by a factor of 2 and 4, respectively. If the authorised maximum iodine in feed for dairy cows and laying hens were reduced to 2 and 3 mg I/kg feed, respectively, the exposure of adult consumers would be below the UL. However, iodine intake in high-consuming toddlers would remain above the UL (1.6-fold). The additives are considered as irritant to the eyes, skin and respiratory tract, and as dermal sensitisers. Exposure by inhalation should be avoided. The use of the additives in animal nutrition is not expected to pose a risk to the environment. The additives are efficacious to meet animal iodine requirements. The FEEDAP Panel recommends that the maximum iodine contents in complete feed be reduced as follows: dairy cows and minor dairy ruminants, 2 mg I/kg; laying hens, 3 mg I/kg; horses, 3 mg I/kg; dogs, 4 mg I/kg; cats, 5 mg I/kg
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Scientific Opinion on the safety and efficacy of iodine compounds (E2) as feed additives for all animal species: Calcium Iodate anhydrous and potassium iodide, based on a dossier submitted by Ajay Europe SARL
Wiley, 2013Co-Authors: Efsa Panel On Additives And Products Or Substances Used In Animal FeedAbstract:Calcium Iodate anhydrous and potassium iodide are considered safe sources of iodine for all animal species/categories when used up to the currently authorised maximum content of total iodine in complete feed, with the exception of horses and dogs, for which maximum tolerated levels are 3 and 4 mg I/kg complete feed, respectively. The limited data available on iodine tolerance in cats support a provisional tolerated level of 5 mg I/kg complete feed. Exposure of consumers was calculated in two scenarios applying the currently authorised maximum iodine contents in feed and reduced contents. The iodine content of food of animal origin, if produced taking account of the currently authorised maximum content of iodine in feed, would represent a substantial risk to high consumers. The risk would originate primarily from the consumption of milk and to a minor extent from eggs. The UL for adults (600 µg/day) and for toddlers (200 µg/day) would be exceeded by a factor of 2 and 4, respectively. If the authorised maximum iodine in feed for dairy cows and laying hens were reduced to 2 and 3 mg I/kg feed, respectively, the exposure of adult consumers would be below the UL. However, iodine intake in high-consuming toddlers would remain above the UL (1.6-fold). The additives are considered as irritant to the eyes, skin and respiratory tract, and as dermal sensitisers. Exposure by inhalation should be avoided. The use of the additives in animal nutrition is not expected to pose a risk to the environment. The additives are efficacious to meet animal iodine requirements. The FEEDAP Panel recommends that the maximum iodine contents in complete feed be reduced as follows: dairy cows and minor dairy ruminants, 2 mg I/kg; laying hens, 3 mg I/kg; horses, 3 mg I/kg; dogs, 4 mg I/kg; cats, 5 mg I/kg
Jie Xu - One of the best experts on this subject based on the ideXlab platform.
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direct coagulation casting of alumina suspension by high valence counter ions using ca io3 2 as coagulating agent
Journal of the American Ceramic Society, 2012Co-Authors: Jie Xu, Xiaoqing Xi, Hexin Li, Fei Qi, Jinlong YangAbstract: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.
Annan Chen - One of the best experts on this subject based on the ideXlab platform.
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rapid in situ solidification of sio2 suspension by direct coagulation casting via controlled release of high valence counter ions from Calcium Iodate and ph shift
Ceramics International, 2017Co-Authors: Annan Chen, Mengyue Liu, Lijin Cheng, Jingyan Chen, Huan Xiao, Xiaoyan Zhang, Yusheng ShiAbstract:Abstract 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.
