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Jinguang Wu - One of the best experts on this subject based on the ideXlab platform.
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interactions between metal ions and carbohydrates syntheses and spectroscopic studies of several lanthanide nitrate d Galactitol complexes
Carbohydrate Research, 2011Co-Authors: Lei Yu, Limin Yang, Jinguang Wu, Yizhuang Xu, Guozhong Zhao, He Wang, Haiyan Wang, Jiaer ChenAbstract:Abstract Two complexes of neutral d -Galactitol (C 6 H 14 O 6 , G) with terbium nitrate, TbGN(I) and TbGN(II), and one complex with samarium nitrate SmGN were synthesized and characterized. From IR, FIR, THz and luminescence spectra the possible coordinations were suggested, and the single-crystal X-ray diffraction results confirm the spectroscopic conclusions. In TbGN(I) (Tb(NO 3 ) 3 ·C 6 H 14 O 6 ·3H 2 O), the Tb 3+ is 9-coordinated with three water molecules and six OH groups from two d -Galactitol molecules. Nitrate ions do not coordinate to metal ions, which is different from other reported lanthanide nitrate– d -Galactitol complexes. In TbGN(II) and SmGN (Ln(NO 3 ) 3 ·C 6 H 14 O 6 ), Ln 3+ is 10-coordinated with six OH groups from two d -Galactitol molecules and four oxygen from two bidentate nitrate ions, and one nitrate ion is hydrogen bonded. No water exists in the structures. d -Galactitol molecules provide their 1-, 2- and 3-hydroxyl groups to coordinate with one metal ion and their 4-, 5- and 6-hydroxyl groups to coordinate with another metal ion in the three structures. There is still a new topological structure that can be observed for lanthanide– d -Galactitol complexes, which indicates that the coordinations between hydroxyl groups and metal ions are complicated.
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preparation and spectroscopic characterization of two hocl3 Galactitol complexes and one ercl3 Galactitol complex
Journal of Molecular Structure, 2011Co-Authors: Lei Yu, Limin Yang, Jinguang Wu, Zheming Wang, Yizhuang Xu, Guozhong Zhao, Weihong Li, Jiaer ChenAbstract:Abstract The interactions between metal ions and hydroxyl groups of carbohydrates are important for their possible biological activities. Here two HoCl3–Galactitol complexes ([Ho(galac)(H2O)3)]Cl3·0.5galac) (HoG(I)) and ([Ho2(galac)(H2O)12)]Cl6·2H2O) (HoG(II))) and one ErCl3–Galactitol complex ([Er(galac)(H2O)3)]Cl3·0.5galac)(ErG)) were prepared and characterized. The possible structures of HoG(I) and ErG were deduced from FTIR, elemental analysis, ESI-MS, FIR, THz and TGA results. It is suggested that Ho3+ or Er3+ is 9-coordinated with six hydroxyl groups from two Galactitol molecules and three water molecules, and another Galactitol molecule is hydrogen-bonded in HoG(I) and ErG and the ratio of metal to ligand is 1:1.5. The structure of HoG(II) was determined by FTIR and X-ray diffraction analyses. The results demonstrate that lanthanide ions with Galactitol may form two compounds in a system and different topological structures can be obtained.
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Preparation and spectroscopic characterization of two HoCl3–Galactitol complexes and one ErCl3–Galactitol complex
Journal of Molecular Structure, 2011Co-Authors: Lei Yu, Limin Yang, Zheming Wang, Yizhuang Xu, Guozhong Zhao, Weihong Li, Jinguang WuAbstract:Abstract The interactions between metal ions and hydroxyl groups of carbohydrates are important for their possible biological activities. Here two HoCl3–Galactitol complexes ([Ho(galac)(H2O)3)]Cl3·0.5galac) (HoG(I)) and ([Ho2(galac)(H2O)12)]Cl6·2H2O) (HoG(II))) and one ErCl3–Galactitol complex ([Er(galac)(H2O)3)]Cl3·0.5galac)(ErG)) were prepared and characterized. The possible structures of HoG(I) and ErG were deduced from FTIR, elemental analysis, ESI-MS, FIR, THz and TGA results. It is suggested that Ho3+ or Er3+ is 9-coordinated with six hydroxyl groups from two Galactitol molecules and three water molecules, and another Galactitol molecule is hydrogen-bonded in HoG(I) and ErG and the ratio of metal to ligand is 1:1.5. The structure of HoG(II) was determined by FTIR and X-ray diffraction analyses. The results demonstrate that lanthanide ions with Galactitol may form two compounds in a system and different topological structures can be obtained.
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Interactions between metal ions and carbohydrates. Syntheses and spectroscopic studies of several lanthanide nitrate–d-Galactitol complexes
Carbohydrate Research, 2011Co-Authors: Lei Yu, Limin Yang, Yizhuang Xu, Guozhong Zhao, He Wang, Haiyan Wang, Jinguang WuAbstract:Abstract Two complexes of neutral d -Galactitol (C 6 H 14 O 6 , G) with terbium nitrate, TbGN(I) and TbGN(II), and one complex with samarium nitrate SmGN were synthesized and characterized. From IR, FIR, THz and luminescence spectra the possible coordinations were suggested, and the single-crystal X-ray diffraction results confirm the spectroscopic conclusions. In TbGN(I) (Tb(NO 3 ) 3 ·C 6 H 14 O 6 ·3H 2 O), the Tb 3+ is 9-coordinated with three water molecules and six OH groups from two d -Galactitol molecules. Nitrate ions do not coordinate to metal ions, which is different from other reported lanthanide nitrate– d -Galactitol complexes. In TbGN(II) and SmGN (Ln(NO 3 ) 3 ·C 6 H 14 O 6 ), Ln 3+ is 10-coordinated with six OH groups from two d -Galactitol molecules and four oxygen from two bidentate nitrate ions, and one nitrate ion is hydrogen bonded. No water exists in the structures. d -Galactitol molecules provide their 1-, 2- and 3-hydroxyl groups to coordinate with one metal ion and their 4-, 5- and 6-hydroxyl groups to coordinate with another metal ion in the three structures. There is still a new topological structure that can be observed for lanthanide– d -Galactitol complexes, which indicates that the coordinations between hydroxyl groups and metal ions are complicated.
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interaction between metal nitrates and carbohydrates the topology coordination behavior of Galactitol with trivalent lanthanide and divalent alkaline earth ions
Inorganic Chemistry, 2007Co-Authors: Yunlan Su, Limin Yang, Zheming Wang, Shifu Weng, Yizhuang Xu, Dujin Wang, Jinguang WuAbstract:It has long been known that metal ions and saccharides are involved in many biochemical processes. In this paper, metal nitrates were used as reactants to detect the coordination structures of the hydroxyl groups of Galactitol in different environments. Three novel crystal structures and FT-IR spectra of metal nitrate-Galactitol complexes of La(N03)3·C 6 H 14 O 6 ·4H 2 O, 2Ca(N03)2·C 6 H 14 O 6 ·H 2 O, and Sr(NO 3 ) 2 ·C 6 H 14 O 6 were examined in an effort to clarify the structural factors that control metal ion interactions with saccharides in aqueous and biological systems. The coordination structures of Galactitol with alkaline earth and lanthanide nitrates in the solid state were compared using FT-IR, Raman, and X-ray diffraction techniques to extensively discuss the coordination rules of different kinds of metal ions. Results provided a model of the coordination sites found in sugars and showed that the introduction of NO 3 - made the coordination modes of Galactitol more diverse and complex than those of the corresponding chloride complexes. Specifically, new coordination modes of Galactitol and complicated topology networks were found in 2Ca(NO 3 ) 2 ·C 6 H 14 O 6 ·H 2 O and Sr(NO 3 ) 2 ·C 6 H 14 O 6 FT-IR results are consistent with the crystal structures and thus provide the possibility of using the similarity of IR spectra to speculate about unknown structures when the compounds are difficult to prepare as single crystals.
Mustafa Ceylan - One of the best experts on this subject based on the ideXlab platform.
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Galactitol hexa stearate and Galactitol hexa palmitate as novel solid–liquid phase change materials for thermal energy storage
Solar Energy, 2011Co-Authors: Ahmet Sari, Alper Bicer, Özgür Lafçi, Mustafa CeylanAbstract:Abstract Galactitol has a melting point of 187.41 °C and a fusion enthalpy of 401.76 J g −1 . Its melting temperature is not suitable for many thermal energy storage applications although it has good latent heat storage capacity compared to the several traditional phase change materials (PCMs). The Galactitol also has high supercooling degree as about 72 °C. These unfavorable properties limit the usage potential of Galactitol in thermal energy storage applications. However, the phase change temperature and supercooling degree of Galactitol can be reduced to a reasonable value and therefore its feasibility for energy storage systems can be increased. For this aim, in this study, Galactitol hexa stearate (GHS) and Galactitol hexa palmitate (GHP) were prepared as novel solid–liquid PCM by means of esterification reaction of the Galactitol with palmitic acid and stearic acid. The GHP and GHS esters were characterized chemically using FT-IR and 1 H NMR techniques. By using DSC analysis method, the melting temperature and latent heat value of the PCMs were determined as 31.78 °C and 201.66 J g −1 for GHP ester and 47.79 °C and 251.05 J g −1 for GHS ester. Thermal cycling test showed that the prepared PCMs had good thermal reliability after thermal 1000 melting–freezing cycles. Thermogravimetric analysis (TGA) results revealed that the PCMs have good thermal stability over their working temperatures. In addition, thermal conductivity of the prepared PCMs was increased as about 26.3% for GHP and 53.3% for GHS by addition of 5 wt.% expanded graphite. Based on all results it can be concluded that the prepared GHP and GHS esters can be considered as promising solid–liquid PCMs for many energy storage applications such as solar energy storage, indoor temperature controlling in buildings, production of smart textile and insulation clothing due to their good energy storage properties.
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Galactitol hexa stearate and Galactitol hexa palmitate as novel solid liquid phase change materials for thermal energy storage
Solar Energy, 2011Co-Authors: Ahmet Sari, Alper Bicer, Özgür Lafçi, Mustafa CeylanAbstract:Abstract Galactitol has a melting point of 187.41 °C and a fusion enthalpy of 401.76 J g −1 . Its melting temperature is not suitable for many thermal energy storage applications although it has good latent heat storage capacity compared to the several traditional phase change materials (PCMs). The Galactitol also has high supercooling degree as about 72 °C. These unfavorable properties limit the usage potential of Galactitol in thermal energy storage applications. However, the phase change temperature and supercooling degree of Galactitol can be reduced to a reasonable value and therefore its feasibility for energy storage systems can be increased. For this aim, in this study, Galactitol hexa stearate (GHS) and Galactitol hexa palmitate (GHP) were prepared as novel solid–liquid PCM by means of esterification reaction of the Galactitol with palmitic acid and stearic acid. The GHP and GHS esters were characterized chemically using FT-IR and 1 H NMR techniques. By using DSC analysis method, the melting temperature and latent heat value of the PCMs were determined as 31.78 °C and 201.66 J g −1 for GHP ester and 47.79 °C and 251.05 J g −1 for GHS ester. Thermal cycling test showed that the prepared PCMs had good thermal reliability after thermal 1000 melting–freezing cycles. Thermogravimetric analysis (TGA) results revealed that the PCMs have good thermal stability over their working temperatures. In addition, thermal conductivity of the prepared PCMs was increased as about 26.3% for GHP and 53.3% for GHS by addition of 5 wt.% expanded graphite. Based on all results it can be concluded that the prepared GHP and GHS esters can be considered as promising solid–liquid PCMs for many energy storage applications such as solar energy storage, indoor temperature controlling in buildings, production of smart textile and insulation clothing due to their good energy storage properties.
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Galactitol hexa stearate and Galactitol hexa palmitate as novel solid-liquid phase change materials for thermal energy storage
Solar Energy, 2011Co-Authors: Ahmet Sari, Alper Bicer, Özgür Lafçi, Mustafa CeylanAbstract:Galactitol has a melting point of 187.41°C and a fusion enthalpy of 401.76Jg -1. Its melting temperature is not suitable for many thermal energy storage applications although it has good latent heat storage capacity compared to the several traditional phase change materials (PCMs). The Galactitol also has high supercooling degree as about 72°C. These unfavorable properties limit the usage potential of Galactitol in thermal energy storage applications. However, the phase change temperature and supercooling degree of Galactitol can be reduced to a reasonable value and therefore its feasibility for energy storage systems can be increased. For this aim, in this study, Galactitol hexa stearate (GHS) and Galactitol hexa palmitate (GHP) were prepared as novel solid-liquid PCM by means of esterification reaction of the Galactitol with palmitic acid and stearic acid. The GHP and GHS esters were characterized chemically using FT-IR and 1H NMR techniques. By using DSC analysis method, the melting temperature and latent heat value of the PCMs were determined as 31.78°C and 201.66Jg -1 for GHP ester and 47.79°C and 251.05Jg -1 for GHS ester. Thermal cycling test showed that the prepared PCMs had good thermal reliability after thermal 1000 melting-freezing cycles. Thermogravimetric analysis (TGA) results revealed that the PCMs have good thermal stability over their working temperatures. In addition, thermal conductivity of the prepared PCMs was increased as about 26.3% for GHP and 53.3% for GHS by addition of 5wt.% expanded graphite. Based on all results it can be concluded that the prepared GHP and GHS esters can be considered as promising solid-liquid PCMs for many energy storage applications such as solar energy storage, indoor temperature controlling in buildings, production of smart textile and insulation clothing due to their good energy storage properties. © 2011 Elsevier Ltd.
Stanton Segal - One of the best experts on this subject based on the ideXlab platform.
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Identification of Galactitol and galactonate in red blood cells by gas chromatography/mass spectrometry.
Clinica chimica acta; international journal of clinical chemistry, 2020Co-Authors: Jie Chen, Claire T Yager, Robert A Reynolds, Stanton SegalAbstract:Because the products of alternate pathways of galactose metabolism, Galactitol and galactonate are important in galactosemia, we sought to identify these compounds in red blood cells (RBC). RBC extracts were trimethylsilylated (TMS) and analyzed by gas chromatography/mass spectrometry (GC/MS). The presence of both Galactitol and galactonate was identified in RBC of 15 galactosemic and 13 normal subjects by their mass spectra and chromatographic comparisons with both unlabeled and 13C labeled standards. The levels in RBC of galactosemics appear to be much higher than those of normal subjects. The determination of these compounds in RBC along with galactose-1-phosphate (gal-1-P) in the same procedure provides the potential for their use in better monitoring of diet therapy in galactosemic patients. Copyright 2002 Elsevier Science B.V.
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urinary Galactitol and galactonate quantified by isotope dilution gas chromatography mass spectrometry
Clinica Chimica Acta, 2006Co-Authors: Claire Yager, Suzanne Wehrli, Stanton SegalAbstract:Abstract Background Measurements of urine Galactitol have been used to monitor the adequacy of diet therapy in the treatment of galactosemia. We have devised a gas chromatographic mass spectrometry (GC/MS) isotope-dilution method for the simultaneous quantification of urine Galactitol and another alternate pathway product, galactonate. Methods We prepared trimethylsilyl (TMS) derivatives and used d -[UL-13C]Galactitol and d -[UL-13C]galactonate as the internal standard for GC/MS. Results obtained with this method were compared with those determined by the established GC method for Galactitol and the NMR method for galactonate. Thirty-three normal urine specimens were analyzed by the isotope dilution technique for Galactitol and galactonate. Results of Galactitol in 6 of these urine specimens along with 18 from classic galactosemics and 19 variant galactosemics were compared with the established GC method. Results for galactonate in 15 urine specimens from galactosemics were compared to the established NMR technique. Results The method was linear up to 200 nmol with lower limits of detection of 1.1 nmol (1.75 mmol/mol creatinine) (Cr) and 0.8 nmol (1.28 mmol/mol Cr) for Galactitol and galactonate, respectively. Intra- and Interassay imprecision ranged from 2.1–6.7% for Galactitol and 3.5–8.0% for galactonate. The excretion of both metabolites was age dependent in both normal and galactosemics. In 12 normal urines from subjects under 1 year, values for Galactitol ranged from 8–107 mmol/mol Cr, and in 7 over age 6, ranged from 2–5 mmol/mol Cr. Under 1 year, the range for galactonate was non-detectable to 231 and in the over 6 years group non-detectable to 25 mmol/mol Cr. In galactosemics under 1 year, the value for Galactitol ranged from 397–743 and for galactonate 92–132 mmol/mol Cr while in nine patients over age 6 the range was 125–274 mmol/mol Cr for Galactitol and 17–46 mmol/mol Cr for galactonate. Conclusions The GC/MS method enables the simultaneous determination of urine Galactitol and galactonate and is precise and useful over the wide range of concentrations needed to assess the galactose burden in patients with galactosemia.
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Urinary Galactitol and galactonate quantified by isotope-dilution gas chromatography-mass spectrometry.
Clinica chimica acta; international journal of clinical chemistry, 2005Co-Authors: Claire Yager, Suzanne Wehrli, Stanton SegalAbstract:Measurements of urine Galactitol have been used to monitor the adequacy of diet therapy in the treatment of galactosemia. We have devised a gas chromatographic mass spectrometry (GC/MS) isotope-dilution method for the simultaneous quantification of urine Galactitol and another alternate pathway product, galactonate. We prepared trimethylsilyl (TMS) derivatives and used D-[UL-13C]Galactitol and D-[UL-13C]galactonate as the internal standard for GC/MS. Results obtained with this method were compared with those determined by the established GC method for Galactitol and the NMR method for galactonate. Thirty-three normal urine specimens were analyzed by the isotope dilution technique for Galactitol and galactonate. Results of Galactitol in 6 of these urine specimens along with 18 from classic galactosemics and 19 variant galactosemics were compared with the established GC method. Results for galactonate in 15 urine specimens from galactosemics were compared to the established NMR technique. The method was linear up to 200 nmol with lower limits of detection of 1.1 nmol (1.75 mmol/mol creatinine) (Cr) and 0.8 nmol (1.28 mmol/mol Cr) for Galactitol and galactonate, respectively. Intra- and Interassay imprecision ranged from 2.1-6.7% for Galactitol and 3.5-8.0% for galactonate. The excretion of both metabolites was age dependent in both normal and galactosemics. In 12 normal urines from subjects under 1 year, values for Galactitol ranged from 8-107 mmol/mol Cr, and in 7 over age 6, ranged from 2-5 mmol/mol Cr. Under 1 year, the range for galactonate was non-detectable to 231 and in the over 6 years group non-detectable to 25 mmol/mol Cr. In galactosemics under 1 year, the value for Galactitol ranged from 397-743 and for galactonate 92-132 mmol/mol Cr while in nine patients over age 6 the range was 125-274 mmol/mol Cr for Galactitol and 17-46 mmol/mol Cr for galactonate. The GC/MS method enables the simultaneous determination of urine Galactitol and galactonate and is precise and useful over the wide range of concentrations needed to assess the galactose burden in patients with galactosemia.
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Galactitol and galactonate in red blood cells of children with the duarte galactosemia genotype
Molecular Genetics and Metabolism, 2005Co-Authors: Can Ficicioglu, Claire Yager, Stanton SegalAbstract:We measured Galactitol, galactonate, and galactose-1-phosphate in the red blood cell (RBC) to elucidate the biochemical phenotype of infants with a Duarte/galactosemia (D/G) genotype by isotope dilution GC/MS. The RBC galactonate, Galactitol and Gal-1-P were quantified in 14 D/G newborns on a lactose containing formula or breast milk, eight D/G newborns on a galactose-free formula, and 18 D/G children between 1 and 2 years of age that were on a regular diet. The results were compared with those of non-galactosemic subjects of comparable age. In the D/G newborns on regular formula/breast milk, the levels of RBC Galactitol, galactonate, and Gal-1-P were significantly higher than those of D/G newborns on diet treatment and non-galactosemic newborns. There was no difference in the levels of RBC Galactitol, galactonate, and Gal-1-P between D/G newborns on a lactose-restricted diet and the control group. There appears to be two different responses to dietary galactose intake in D/G children. The first group of D/G children placed on a regular diet after a year of lactose restriction had higher RBC Galactitol, galactonate levels than those of non-galactosemic children. The mean level of RBC galactonate was higher and the mean value of RBC Galactitol was as high as that of galactosemic (G/G) patients on diet treatment. The second group of D/G children on a regular diet had normal levels of RBC Galactitol and galactonate. The levels of RBC Gal-1-P were normal in both groups of D/G patients. The alternative pathway products may reflect galactose intake better than RBC Gal-1-P in D/G children.
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Galactitol and galactonate in red blood cells of children with the Duarte/galactosemia genotype
Molecular Genetics and Metabolism, 2004Co-Authors: Can Ficicioglu, Claire Yager, Stanton SegalAbstract:We measured Galactitol, galactonate, and galactose-1-phosphate in the red blood cell (RBC) to elucidate the biochemical phenotype of infants with a Duarte/galactosemia (D/G) genotype by isotope dilution GC/MS. The RBC galactonate, Galactitol and Gal-1-P were quantified in 14 D/G newborns on a lactose containing formula or breast milk, eight D/G newborns on a galactose-free formula, and 18 D/G children between 1 and 2 years of age that were on a regular diet. The results were compared with those of non-galactosemic subjects of comparable age. In the D/G newborns on regular formula/breast milk, the levels of RBC Galactitol, galactonate, and Gal-1-P were significantly higher than those of D/G newborns on diet treatment and non-galactosemic newborns. There was no difference in the levels of RBC Galactitol, galactonate, and Gal-1-P between D/G newborns on a lactose-restricted diet and the control group. There appears to be two different responses to dietary galactose intake in D/G children. The first group of D/G children placed on a regular diet after a year of lactose restriction had higher RBC Galactitol, galactonate levels than those of non-galactosemic children. The mean level of RBC galactonate was higher and the mean value of RBC Galactitol was as high as that of galactosemic (G/G) patients on diet treatment. The second group of D/G children on a regular diet had normal levels of RBC Galactitol and galactonate. The levels of RBC Gal-1-P were normal in both groups of D/G patients. The alternative pathway products may reflect galactose intake better than RBC Gal-1-P in D/G children.
Limin Yang - One of the best experts on this subject based on the ideXlab platform.
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interactions between metal ions and carbohydrates syntheses and spectroscopic studies of several lanthanide nitrate d Galactitol complexes
Carbohydrate Research, 2011Co-Authors: Lei Yu, Limin Yang, Jinguang Wu, Yizhuang Xu, Guozhong Zhao, He Wang, Haiyan Wang, Jiaer ChenAbstract:Abstract Two complexes of neutral d -Galactitol (C 6 H 14 O 6 , G) with terbium nitrate, TbGN(I) and TbGN(II), and one complex with samarium nitrate SmGN were synthesized and characterized. From IR, FIR, THz and luminescence spectra the possible coordinations were suggested, and the single-crystal X-ray diffraction results confirm the spectroscopic conclusions. In TbGN(I) (Tb(NO 3 ) 3 ·C 6 H 14 O 6 ·3H 2 O), the Tb 3+ is 9-coordinated with three water molecules and six OH groups from two d -Galactitol molecules. Nitrate ions do not coordinate to metal ions, which is different from other reported lanthanide nitrate– d -Galactitol complexes. In TbGN(II) and SmGN (Ln(NO 3 ) 3 ·C 6 H 14 O 6 ), Ln 3+ is 10-coordinated with six OH groups from two d -Galactitol molecules and four oxygen from two bidentate nitrate ions, and one nitrate ion is hydrogen bonded. No water exists in the structures. d -Galactitol molecules provide their 1-, 2- and 3-hydroxyl groups to coordinate with one metal ion and their 4-, 5- and 6-hydroxyl groups to coordinate with another metal ion in the three structures. There is still a new topological structure that can be observed for lanthanide– d -Galactitol complexes, which indicates that the coordinations between hydroxyl groups and metal ions are complicated.
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preparation and spectroscopic characterization of two hocl3 Galactitol complexes and one ercl3 Galactitol complex
Journal of Molecular Structure, 2011Co-Authors: Lei Yu, Limin Yang, Jinguang Wu, Zheming Wang, Yizhuang Xu, Guozhong Zhao, Weihong Li, Jiaer ChenAbstract:Abstract The interactions between metal ions and hydroxyl groups of carbohydrates are important for their possible biological activities. Here two HoCl3–Galactitol complexes ([Ho(galac)(H2O)3)]Cl3·0.5galac) (HoG(I)) and ([Ho2(galac)(H2O)12)]Cl6·2H2O) (HoG(II))) and one ErCl3–Galactitol complex ([Er(galac)(H2O)3)]Cl3·0.5galac)(ErG)) were prepared and characterized. The possible structures of HoG(I) and ErG were deduced from FTIR, elemental analysis, ESI-MS, FIR, THz and TGA results. It is suggested that Ho3+ or Er3+ is 9-coordinated with six hydroxyl groups from two Galactitol molecules and three water molecules, and another Galactitol molecule is hydrogen-bonded in HoG(I) and ErG and the ratio of metal to ligand is 1:1.5. The structure of HoG(II) was determined by FTIR and X-ray diffraction analyses. The results demonstrate that lanthanide ions with Galactitol may form two compounds in a system and different topological structures can be obtained.
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Preparation and spectroscopic characterization of two HoCl3–Galactitol complexes and one ErCl3–Galactitol complex
Journal of Molecular Structure, 2011Co-Authors: Lei Yu, Limin Yang, Zheming Wang, Yizhuang Xu, Guozhong Zhao, Weihong Li, Jinguang WuAbstract:Abstract The interactions between metal ions and hydroxyl groups of carbohydrates are important for their possible biological activities. Here two HoCl3–Galactitol complexes ([Ho(galac)(H2O)3)]Cl3·0.5galac) (HoG(I)) and ([Ho2(galac)(H2O)12)]Cl6·2H2O) (HoG(II))) and one ErCl3–Galactitol complex ([Er(galac)(H2O)3)]Cl3·0.5galac)(ErG)) were prepared and characterized. The possible structures of HoG(I) and ErG were deduced from FTIR, elemental analysis, ESI-MS, FIR, THz and TGA results. It is suggested that Ho3+ or Er3+ is 9-coordinated with six hydroxyl groups from two Galactitol molecules and three water molecules, and another Galactitol molecule is hydrogen-bonded in HoG(I) and ErG and the ratio of metal to ligand is 1:1.5. The structure of HoG(II) was determined by FTIR and X-ray diffraction analyses. The results demonstrate that lanthanide ions with Galactitol may form two compounds in a system and different topological structures can be obtained.
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Interactions between metal ions and carbohydrates. Syntheses and spectroscopic studies of several lanthanide nitrate–d-Galactitol complexes
Carbohydrate Research, 2011Co-Authors: Lei Yu, Limin Yang, Yizhuang Xu, Guozhong Zhao, He Wang, Haiyan Wang, Jinguang WuAbstract:Abstract Two complexes of neutral d -Galactitol (C 6 H 14 O 6 , G) with terbium nitrate, TbGN(I) and TbGN(II), and one complex with samarium nitrate SmGN were synthesized and characterized. From IR, FIR, THz and luminescence spectra the possible coordinations were suggested, and the single-crystal X-ray diffraction results confirm the spectroscopic conclusions. In TbGN(I) (Tb(NO 3 ) 3 ·C 6 H 14 O 6 ·3H 2 O), the Tb 3+ is 9-coordinated with three water molecules and six OH groups from two d -Galactitol molecules. Nitrate ions do not coordinate to metal ions, which is different from other reported lanthanide nitrate– d -Galactitol complexes. In TbGN(II) and SmGN (Ln(NO 3 ) 3 ·C 6 H 14 O 6 ), Ln 3+ is 10-coordinated with six OH groups from two d -Galactitol molecules and four oxygen from two bidentate nitrate ions, and one nitrate ion is hydrogen bonded. No water exists in the structures. d -Galactitol molecules provide their 1-, 2- and 3-hydroxyl groups to coordinate with one metal ion and their 4-, 5- and 6-hydroxyl groups to coordinate with another metal ion in the three structures. There is still a new topological structure that can be observed for lanthanide– d -Galactitol complexes, which indicates that the coordinations between hydroxyl groups and metal ions are complicated.
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interaction between metal nitrates and carbohydrates the topology coordination behavior of Galactitol with trivalent lanthanide and divalent alkaline earth ions
Inorganic Chemistry, 2007Co-Authors: Yunlan Su, Limin Yang, Zheming Wang, Shifu Weng, Yizhuang Xu, Dujin Wang, Jinguang WuAbstract:It has long been known that metal ions and saccharides are involved in many biochemical processes. In this paper, metal nitrates were used as reactants to detect the coordination structures of the hydroxyl groups of Galactitol in different environments. Three novel crystal structures and FT-IR spectra of metal nitrate-Galactitol complexes of La(N03)3·C 6 H 14 O 6 ·4H 2 O, 2Ca(N03)2·C 6 H 14 O 6 ·H 2 O, and Sr(NO 3 ) 2 ·C 6 H 14 O 6 were examined in an effort to clarify the structural factors that control metal ion interactions with saccharides in aqueous and biological systems. The coordination structures of Galactitol with alkaline earth and lanthanide nitrates in the solid state were compared using FT-IR, Raman, and X-ray diffraction techniques to extensively discuss the coordination rules of different kinds of metal ions. Results provided a model of the coordination sites found in sugars and showed that the introduction of NO 3 - made the coordination modes of Galactitol more diverse and complex than those of the corresponding chloride complexes. Specifically, new coordination modes of Galactitol and complicated topology networks were found in 2Ca(NO 3 ) 2 ·C 6 H 14 O 6 ·H 2 O and Sr(NO 3 ) 2 ·C 6 H 14 O 6 FT-IR results are consistent with the crystal structures and thus provide the possibility of using the similarity of IR spectra to speculate about unknown structures when the compounds are difficult to prepare as single crystals.
Ahmet Sari - One of the best experts on this subject based on the ideXlab platform.
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Galactitol hexa stearate and Galactitol hexa palmitate as novel solid–liquid phase change materials for thermal energy storage
Solar Energy, 2011Co-Authors: Ahmet Sari, Alper Bicer, Özgür Lafçi, Mustafa CeylanAbstract:Abstract Galactitol has a melting point of 187.41 °C and a fusion enthalpy of 401.76 J g −1 . Its melting temperature is not suitable for many thermal energy storage applications although it has good latent heat storage capacity compared to the several traditional phase change materials (PCMs). The Galactitol also has high supercooling degree as about 72 °C. These unfavorable properties limit the usage potential of Galactitol in thermal energy storage applications. However, the phase change temperature and supercooling degree of Galactitol can be reduced to a reasonable value and therefore its feasibility for energy storage systems can be increased. For this aim, in this study, Galactitol hexa stearate (GHS) and Galactitol hexa palmitate (GHP) were prepared as novel solid–liquid PCM by means of esterification reaction of the Galactitol with palmitic acid and stearic acid. The GHP and GHS esters were characterized chemically using FT-IR and 1 H NMR techniques. By using DSC analysis method, the melting temperature and latent heat value of the PCMs were determined as 31.78 °C and 201.66 J g −1 for GHP ester and 47.79 °C and 251.05 J g −1 for GHS ester. Thermal cycling test showed that the prepared PCMs had good thermal reliability after thermal 1000 melting–freezing cycles. Thermogravimetric analysis (TGA) results revealed that the PCMs have good thermal stability over their working temperatures. In addition, thermal conductivity of the prepared PCMs was increased as about 26.3% for GHP and 53.3% for GHS by addition of 5 wt.% expanded graphite. Based on all results it can be concluded that the prepared GHP and GHS esters can be considered as promising solid–liquid PCMs for many energy storage applications such as solar energy storage, indoor temperature controlling in buildings, production of smart textile and insulation clothing due to their good energy storage properties.
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Galactitol hexa stearate and Galactitol hexa palmitate as novel solid liquid phase change materials for thermal energy storage
Solar Energy, 2011Co-Authors: Ahmet Sari, Alper Bicer, Özgür Lafçi, Mustafa CeylanAbstract:Abstract Galactitol has a melting point of 187.41 °C and a fusion enthalpy of 401.76 J g −1 . Its melting temperature is not suitable for many thermal energy storage applications although it has good latent heat storage capacity compared to the several traditional phase change materials (PCMs). The Galactitol also has high supercooling degree as about 72 °C. These unfavorable properties limit the usage potential of Galactitol in thermal energy storage applications. However, the phase change temperature and supercooling degree of Galactitol can be reduced to a reasonable value and therefore its feasibility for energy storage systems can be increased. For this aim, in this study, Galactitol hexa stearate (GHS) and Galactitol hexa palmitate (GHP) were prepared as novel solid–liquid PCM by means of esterification reaction of the Galactitol with palmitic acid and stearic acid. The GHP and GHS esters were characterized chemically using FT-IR and 1 H NMR techniques. By using DSC analysis method, the melting temperature and latent heat value of the PCMs were determined as 31.78 °C and 201.66 J g −1 for GHP ester and 47.79 °C and 251.05 J g −1 for GHS ester. Thermal cycling test showed that the prepared PCMs had good thermal reliability after thermal 1000 melting–freezing cycles. Thermogravimetric analysis (TGA) results revealed that the PCMs have good thermal stability over their working temperatures. In addition, thermal conductivity of the prepared PCMs was increased as about 26.3% for GHP and 53.3% for GHS by addition of 5 wt.% expanded graphite. Based on all results it can be concluded that the prepared GHP and GHS esters can be considered as promising solid–liquid PCMs for many energy storage applications such as solar energy storage, indoor temperature controlling in buildings, production of smart textile and insulation clothing due to their good energy storage properties.
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Galactitol hexa stearate and Galactitol hexa palmitate as novel solid-liquid phase change materials for thermal energy storage
Solar Energy, 2011Co-Authors: Ahmet Sari, Alper Bicer, Özgür Lafçi, Mustafa CeylanAbstract:Galactitol has a melting point of 187.41°C and a fusion enthalpy of 401.76Jg -1. Its melting temperature is not suitable for many thermal energy storage applications although it has good latent heat storage capacity compared to the several traditional phase change materials (PCMs). The Galactitol also has high supercooling degree as about 72°C. These unfavorable properties limit the usage potential of Galactitol in thermal energy storage applications. However, the phase change temperature and supercooling degree of Galactitol can be reduced to a reasonable value and therefore its feasibility for energy storage systems can be increased. For this aim, in this study, Galactitol hexa stearate (GHS) and Galactitol hexa palmitate (GHP) were prepared as novel solid-liquid PCM by means of esterification reaction of the Galactitol with palmitic acid and stearic acid. The GHP and GHS esters were characterized chemically using FT-IR and 1H NMR techniques. By using DSC analysis method, the melting temperature and latent heat value of the PCMs were determined as 31.78°C and 201.66Jg -1 for GHP ester and 47.79°C and 251.05Jg -1 for GHS ester. Thermal cycling test showed that the prepared PCMs had good thermal reliability after thermal 1000 melting-freezing cycles. Thermogravimetric analysis (TGA) results revealed that the PCMs have good thermal stability over their working temperatures. In addition, thermal conductivity of the prepared PCMs was increased as about 26.3% for GHP and 53.3% for GHS by addition of 5wt.% expanded graphite. Based on all results it can be concluded that the prepared GHP and GHS esters can be considered as promising solid-liquid PCMs for many energy storage applications such as solar energy storage, indoor temperature controlling in buildings, production of smart textile and insulation clothing due to their good energy storage properties. © 2011 Elsevier Ltd.
