The influences of magnesium and ferric ions in their different ratios on the rate of gypsum crystallization were studied under the conditions similar to those of wet flue-gas desulfurization(WFGD). The results show ...The influences of magnesium and ferric ions in their different ratios on the rate of gypsum crystallization were studied under the conditions similar to those of wet flue-gas desulfurization(WFGD). The results show that addition of both Mg^2+ and Fe^3+ increased induction time and decreased the growth efficiency up to 50% compared with the baseline(without impurities) depending on the concentration and the type of impurity. The effects of Mg^2+ and Fe^3+ on the surface energy and the rate of nucleation were estimated by employing the classical nucleation theory. The surface energy decreased by 8% and 14% with the addition of 0.02 mol/L magnesium or ferric ions, respectively, compared to the baseline. Mg^2+ and Fe^3+ made the growth rate of the (020), (021) and (040) faces of gypsum crystal a much greater reduction, which leads to the formation of needle crystals compared to the baseline which favors the formation of plate or flakes. Furthermore, an edge detection program was developed to quantify the effects of impurities on the filtration rate of gypsum product. The results show that the inhibition efficiency of the presence of 0.02 mol/L Mg^2+ and Fe^3+ on the filtration rate of gypsum crystal ranges from 22% to 39%.展开更多
The absolute configuration of mitomycin C was determined?by X-ray single crystal diffraction?(CuKα), and a new?crystalline?dihydrate of mitomycin C had been prepared. The?experiment?result?provides?a definitive answe...The absolute configuration of mitomycin C was determined?by X-ray single crystal diffraction?(CuKα), and a new?crystalline?dihydrate of mitomycin C had been prepared. The?experiment?result?provides?a definitive answer?to the real absolute configuration of mitomycin C and may put an end to the dispute?that baffles?researchers for decades.?At the same time, some contentious structures?about the mitomycin C in?American Pharmacopoeia?USP36-NF31,?Chinese pharmacopoeia?2015?edtion?and numbers of?literatures are marked. The absolute configuration?is?also verified?by?1D (1H?and?13C) and 2D (HSQC, HMBC,?1H-1H?COSY?and?NOESY) NMR studies?indirectly. Powder X-ray diffraction (PXRD) pattern of the?mitomycin C dihydrate?is similar to that calculated for?it, which?suggests that the purity?of?sample?is excellent.展开更多
The optimized molecular structures and vibrational frequencies of 4-mercaptopyridine(4MPY) monomer and its dihydrate were studied by means of the density functional theory( DFT), viz. B3LYP method with the 6-311 ...The optimized molecular structures and vibrational frequencies of 4-mercaptopyridine(4MPY) monomer and its dihydrate were studied by means of the density functional theory( DFT), viz. B3LYP method with the 6-311 + + G (d,p) basis set. On the basis of the calculations, the assignments of the vibrational spectra of the monomer and the dihydrate were performed, and so were investigated the changes in the structure and the vibrational spectrum of the di- hydrate as well as the intermolecular force resulting in the formation of the dihydrate. The calculated results show that each of the water molecule planes is vertical to the pyridine ring plane in the dihydrate that is formed via the H-bonds between 4MPY and water molecules. Furthermore, the structure and the vibrational spectrum of 4MPY can be considerably affected by the water molecules.展开更多
1 Introduction Calcium sulfate deposition is one of the most important and serious problems faced by heat transfer equipment during operation(Pavlos et al.,1999;Liu et al.,1996).The crystallization of calcium sulfate ...1 Introduction Calcium sulfate deposition is one of the most important and serious problems faced by heat transfer equipment during operation(Pavlos et al.,1999;Liu et al.,1996).The crystallization of calcium sulfate is known as a major展开更多
Single crystals of two 1,3-phenylenebis(oxy)diacetic acid(C10H10O8) compounds 1 and 2 were obtained via slow evaporation.The compounds were characterized by elemental analysis,IR and single-crystal X-ray diffracti...Single crystals of two 1,3-phenylenebis(oxy)diacetic acid(C10H10O8) compounds 1 and 2 were obtained via slow evaporation.The compounds were characterized by elemental analysis,IR and single-crystal X-ray diffraction.Compound 1(C10H14O8) crystallizes in the triclinic system,space group P1 with a = 6.3751(6),b = 8.5311(8),c = 11.4510(11)A,α = 93.3650(10),β = 105.3190(10),γ = 97.2140(10)°,V = 593.15(10) A^3,Z = 2,Mr = 262.21,Dc = 1.468 g/cm^3,F(000) = 276,GOOF = 1.005,° = 0.129 mm^-1,the final R = 0.0361 and w R = 0.0802 for 1854 observed reflections with I 〉 2σ(I).Compound 2(C30H28N2O12) crystallizes in the triclinic system,space group P1 with a = 9.7416(13),b = 11.839(2),c = 12.9828(13) A,α = 74.191(4),β = 77.953(2),γ = 74.726(3)°,V = 1374.5(3) A^3,Z = 2,Mr = 608.54,Dc = 1.470 g/cm^3,F(000) = 636,GOOF = 1.061,° = 0.115 mm^-1,the final R = 0.0500 and w R = 0.1221 for 3966 observed reflections with I 〉 2σ(I).Both compounds 1 and 2 exhibit 3D supramolecular structures under hydrogen bonding interactions.The results of preliminary antibacterial activity show that the title compounds display moderate antibacterial activities against the tested gram positive bacteria(S.aureus,C.albicans and B.subtilis) and gram negative bacteria(E.coli and P.aeruginosa).展开更多
A new method of the multiple rates isotemperature is proposed to define the most probable mechanismg(α) of thermal anlaysis; the iterative isoconversional procedure has been employed to estimate apparent activation e...A new method of the multiple rates isotemperature is proposed to define the most probable mechanismg(α) of thermal anlaysis; the iterative isoconversional procedure has been employed to estimate apparent activation energyE; the pre-exponential factorA is obtained on the basis ofE andg(α). By this new method, the thermal analysis kinetics triplet of dehydration of cobalt oxalate dihydrate is determined, apparent activation energyE is 99.84 kJ·mol?1; pre-exponential factorA is 3.427×109–3.872×109 s?1 and the most probable mechanism belongs to nucleation and growth,A m model, the range ofm is from 1.50 to 1.70. Key words multiple rates isotemperature method - isoconversional method - cobalt oxalate dihydrate - accomodation function - differential scanning calorimetry (DSC) CLC number O 636.1 Foundation item: Supported by the Key Foundation of the Science and Technology Committee of Hubei Province (2001ABA009)Biography: Li Li-qing (1977-), female, Master candidate, research direction: material synthesize and thermal analysis kinetics.展开更多
t-Butyldimethylsilyl (TBDMS) ether can be cleaved upon refluxing in acetone/H2O (95 : 5) in the presence of a catalytic amount of copper (II) chloride dihydrate (5 mmol %).
A simple, precise, accurate and sensitive reverse phase high performance liquid chromatographic method for simultaneous estimation of lisinopril dihydrate and its degradation products occuring under different ICH pres...A simple, precise, accurate and sensitive reverse phase high performance liquid chromatographic method for simultaneous estimation of lisinopril dihydrate and its degradation products occuring under different ICH prescribed stress conditions has been modified. Drug was resolved on a C18 column, utilizing modified mobile phase of tetra butyl ammonium hydroxide solution and acetonitrile. Ultra violet detection was carried out at 210 nm. The method was modified with respect to linearity, precision, accuracy, selectivity, specificity and ruggedness. The results obtained revealed that lisinopril dihydrate was an active product slightly changed under stress conditions.展开更多
As a kind of efficient photocatalyst,coordination polymers(CPs) have gained much attention in recent years.However,their safety issue and time-consuming synthesis impede their practical application.Here in this paper ...As a kind of efficient photocatalyst,coordination polymers(CPs) have gained much attention in recent years.However,their safety issue and time-consuming synthesis impede their practical application.Here in this paper we first demonstrate the facile synthesis and photocatalytic degradation performance of 1D α-ferrous oxalate dihydrate(α-FOD),which is one of the simplest CPs.A unique two-pathway photocatalytic mechanism which combines traditional photocatalytic and photo-initiated Fenton oxidations has been proposed.The excellent photocatalytic performance and cost-effective fabrication make α-FOD a new promising candidate for the photocatalytic degradation of organic pollutants in practical applications.展开更多
The thermal decomposition of the magnesium oxalate dihydrate in a static air atmosphere was investigated by TG-DTG techniques. The intermediate and residue of each decomposition were identified from their TG curve. Th...The thermal decomposition of the magnesium oxalate dihydrate in a static air atmosphere was investigated by TG-DTG techniques. The intermediate and residue of each decomposition were identified from their TG curve. The kinetic triplet, the activation energy E, the pre-exponential factor A and the mechanism functionsf(a) were obtained from analysis of the TG-DTG curves of thermal decomposition of the first stage and the second stage by the Popesou method and the Flynn-Wall-Ozawa method.展开更多
An efficient green protocol is described for the preparation of highly functionalized piperidines via a one-pot five-component reaction between aromatic aldehydes,anilines andβ-ketoesters in the presence of oxalic ac...An efficient green protocol is described for the preparation of highly functionalized piperidines via a one-pot five-component reaction between aromatic aldehydes,anilines andβ-ketoesters in the presence of oxalic acid dihydrate as catalyst in ethanol at ambient temperature.The structure as well as the relative stereochemistry of these compounds was confirmed by single X-ray crystallographic analysis.展开更多
The mixture of CaHPO 4·2H 2O and CaCO 3 was ground in an aqueous system under appropriate conditions to investigate the mechanochemical reaction for the synthesis of crystalline hydroxyapatite (HA) powder. Hyd...The mixture of CaHPO 4·2H 2O and CaCO 3 was ground in an aqueous system under appropriate conditions to investigate the mechanochemical reaction for the synthesis of crystalline hydroxyapatite (HA) powder. Hydroxyapatite of high crystallinity powder including trace Ca 10 (PO 4) 6CO 3(OH) and Ca 9HPO 4(PO 4) 6OH can be synthesized by mechanical activation without further thermal treatment at a high temperature. The synthesis reaction during the grinding process was almost completed within 1h. The as-ground powder exhibits a particle distribution of 20-100nm in size with a spherical or rodlike morphology. The composition and degree of crystallinity of the mechanochemical synthesized hydroxyapatite powders were coincident with the cement-type hydroxyapatite.展开更多
Electrodeposition technique was used to coat calcium phosphate on carbon fiber which can be used to reinforce hydroxyapatite. The differences between fibers treated with and without nitric acid in electrodeposition we...Electrodeposition technique was used to coat calcium phosphate on carbon fiber which can be used to reinforce hydroxyapatite. The differences between fibers treated with and without nitric acid in electrodeposition were evaluated. The X-ray diffractometry results show that CaHPO4·2H2O is obtained as the kind of calcium phosphate coating on carbon fiber. The scanning electron microscopy photographs and deposit kinetic curve indicate that the influences of the functional group attained by nitric acid treatment, the crystal morphology and crystallization of the coating layers on the fiber with and without treatment rate are obviously different. The functional group, especially the acidic group, can act as nucleation centers of electrochemical crystallization.展开更多
α-calcium sulfate hemihydrate (α-HH) is known to be suitable for application as bone void filler. High percentage of α-HH is obviously needed for medical applications, especially for implantation. Three commerciall...α-calcium sulfate hemihydrate (α-HH) is known to be suitable for application as bone void filler. High percentage of α-HH is obviously needed for medical applications, especially for implantation. Three commercially available calcium sulfate dihydrates (DH, CaSO4·2H2O) with different sizes and surface morphologies were used as starting materials to synthesize high percentage α-HH via a hydrothermal method. The median particle sizes of the three types of DH were 946.7 μm, 162.4 μm and 62.4 μm, respectively. They were named as DH-L, DH-M and DH-S in this paper. The particle size distribution, morphology and phase composition of the raw materials were evaluated before synthesis. SEM results revealed that DH-L consisted of irregular large particles, while DH-M and DH-S were composed of plate-like particles with some small ones. High percentage HH can be obtained with proper synthesis parameters by hydrothermal method, specifically, 105 °C/90 min for DH-L (achieving 98.8% HH), 105°C/30 min for DH-M (achieving 96.7% HH) and 100°C/45 min for DH-S (achieving 98.4% HH). All the synthesized HH were hexagonal columns, demonstrating that they were α-phase HH. The particle size and morphology of starting material (DH) have significant influences on not only the rate of phase transition but also the morphology of the synthesized α-HH. Calcium sulfate dihydrate cements were prepared by the synthesized α-HH. The highest compressive strength of calcium sulfate dihydrate cement was 17.2 MPa. The results show that the preparation of high percentage α-HH is feasible via a hydrothermal method and the process can be further scaled up to industrial scale production.展开更多
Objectives: To define clinical differences in the acute phase response and serum acute phase reactants between gout, pseudogout and crystal-induced arthritis in the presence of non-articular infections (CAI). Patients...Objectives: To define clinical differences in the acute phase response and serum acute phase reactants between gout, pseudogout and crystal-induced arthritis in the presence of non-articular infections (CAI). Patients and Methods: Eleven patients with definite gout, 12 patients with pseudogout and 5 patients with CIA were included in the study. Results: The erythrocyte sedimentation rate (ESR) was significantly different between gout (68.2 ± 49.9 mm/Hr) and CIA (113.8 ± 37.2 mm/Hr) but not between gout and pseudogout (83.9 ± 45.6 mm/Hr) or between pseudogout and CIA. The C-reactive protein (CRP) was significantly increased between gout (10.1 ± 7.9 mg/dL) and pseudogout (18.9 ± 9.8 mg/dL), gout and CIA (36.5 ± 12.4 mg/dL) as well as between pseudogout and CIA. The peripheral white cell count was significantly different between gout (9.27 ± 3.7 k/μL) and CIA (16.5 ± 6.8 k/μL), and between pseudogout (8.9 ± 3.2 k/μL) and CIA. Conclusions: Measurement of ESR and CRP are helpful in crystal-induced arthritis. The CRP has more discriminating utility than the ESR in distinguishing between gout, pseudogout and CIA. Peripheral wbc is most useful for differentiating crystal-induced arthritis from CIA.展开更多
A novel silver-based dihydric alcohol extractant was substituted for ionic liquids to enrich methyl linolenate(C18-3)from tallow seed oil methyl ester in this study.The interactions among dihydric alcohol,Ag(I)and C18...A novel silver-based dihydric alcohol extractant was substituted for ionic liquids to enrich methyl linolenate(C18-3)from tallow seed oil methyl ester in this study.The interactions among dihydric alcohol,Ag(I)and C18-3 were explored by FT-IR spectroscopy.The effects of dihydric alcohol structure,carrier Ag(I)concentration,temperature and initial feed concentration on extraction yield and selectivity were reported.The good extraction performance was achieved by 1,4-butanediol containing AgBF4.The complexation of Ag(I)with C18-3 was dominant in extraction operation rather than physical partition.Furthermore,a multi-step reverse extraction method was proposed to obtain C18-3 product and regenerate the extractant.1-Hexene as the stripping phase can facilitate C18-3 reverse extraction.The content of C18-3 in the product was up to 93.36%,and the yield was 73.76%.This work opened a new route for the utilization of the dihydric alcohol properties to manipulate the carrier efficiency for extracting unsaturated fatty acid methyl esters at a lower cost.展开更多
The effect of five dihydric alcohols on the fixation rate and K/S value of reactive dyes on cotton fabrics was investigated.Results show that the more primary hydroxyl groups are contained in the isomeric dihydric alc...The effect of five dihydric alcohols on the fixation rate and K/S value of reactive dyes on cotton fabrics was investigated.Results show that the more primary hydroxyl groups are contained in the isomeric dihydric alcohols,the greater activity of reacting with the reactive dye.Longer carbon chain also increases the reactivity of dihydric alcohols with reactive dyes.This study provides a theoretical basis for the selection of suitable dihydric alcohols in preparation reactive dye inkjet printing ink.展开更多
基金Supported by the State 11.5 Support Plan(No.2006BAA01B04)the New Century Excellent Talent Support Plan of China (No.NCET-06-0513)
文摘The influences of magnesium and ferric ions in their different ratios on the rate of gypsum crystallization were studied under the conditions similar to those of wet flue-gas desulfurization(WFGD). The results show that addition of both Mg^2+ and Fe^3+ increased induction time and decreased the growth efficiency up to 50% compared with the baseline(without impurities) depending on the concentration and the type of impurity. The effects of Mg^2+ and Fe^3+ on the surface energy and the rate of nucleation were estimated by employing the classical nucleation theory. The surface energy decreased by 8% and 14% with the addition of 0.02 mol/L magnesium or ferric ions, respectively, compared to the baseline. Mg^2+ and Fe^3+ made the growth rate of the (020), (021) and (040) faces of gypsum crystal a much greater reduction, which leads to the formation of needle crystals compared to the baseline which favors the formation of plate or flakes. Furthermore, an edge detection program was developed to quantify the effects of impurities on the filtration rate of gypsum product. The results show that the inhibition efficiency of the presence of 0.02 mol/L Mg^2+ and Fe^3+ on the filtration rate of gypsum crystal ranges from 22% to 39%.
文摘The absolute configuration of mitomycin C was determined?by X-ray single crystal diffraction?(CuKα), and a new?crystalline?dihydrate of mitomycin C had been prepared. The?experiment?result?provides?a definitive answer?to the real absolute configuration of mitomycin C and may put an end to the dispute?that baffles?researchers for decades.?At the same time, some contentious structures?about the mitomycin C in?American Pharmacopoeia?USP36-NF31,?Chinese pharmacopoeia?2015?edtion?and numbers of?literatures are marked. The absolute configuration?is?also verified?by?1D (1H?and?13C) and 2D (HSQC, HMBC,?1H-1H?COSY?and?NOESY) NMR studies?indirectly. Powder X-ray diffraction (PXRD) pattern of the?mitomycin C dihydrate?is similar to that calculated for?it, which?suggests that the purity?of?sample?is excellent.
文摘The optimized molecular structures and vibrational frequencies of 4-mercaptopyridine(4MPY) monomer and its dihydrate were studied by means of the density functional theory( DFT), viz. B3LYP method with the 6-311 + + G (d,p) basis set. On the basis of the calculations, the assignments of the vibrational spectra of the monomer and the dihydrate were performed, and so were investigated the changes in the structure and the vibrational spectrum of the di- hydrate as well as the intermolecular force resulting in the formation of the dihydrate. The calculated results show that each of the water molecule planes is vertical to the pyridine ring plane in the dihydrate that is formed via the H-bonds between 4MPY and water molecules. Furthermore, the structure and the vibrational spectrum of 4MPY can be considerably affected by the water molecules.
基金financial support of National Nature Science Foundation (21376178)TIDA giant growth plan (2011-XJR13020)+3 种基金Tianjin Science and technology support program (12ZCDZSF06900)Tianjin University of Science and Technology fund for scientific research (20120119)Tianjin education commission program (20130509)Research fund for the doctoral program of higher education of China(20131208120001)
文摘1 Introduction Calcium sulfate deposition is one of the most important and serious problems faced by heat transfer equipment during operation(Pavlos et al.,1999;Liu et al.,1996).The crystallization of calcium sulfate is known as a major
基金Supported by the National Natural Science Foundation of China(No.21264011,20961007)the Aviation Fund(No.2014ZF56020)
文摘Single crystals of two 1,3-phenylenebis(oxy)diacetic acid(C10H10O8) compounds 1 and 2 were obtained via slow evaporation.The compounds were characterized by elemental analysis,IR and single-crystal X-ray diffraction.Compound 1(C10H14O8) crystallizes in the triclinic system,space group P1 with a = 6.3751(6),b = 8.5311(8),c = 11.4510(11)A,α = 93.3650(10),β = 105.3190(10),γ = 97.2140(10)°,V = 593.15(10) A^3,Z = 2,Mr = 262.21,Dc = 1.468 g/cm^3,F(000) = 276,GOOF = 1.005,° = 0.129 mm^-1,the final R = 0.0361 and w R = 0.0802 for 1854 observed reflections with I 〉 2σ(I).Compound 2(C30H28N2O12) crystallizes in the triclinic system,space group P1 with a = 9.7416(13),b = 11.839(2),c = 12.9828(13) A,α = 74.191(4),β = 77.953(2),γ = 74.726(3)°,V = 1374.5(3) A^3,Z = 2,Mr = 608.54,Dc = 1.470 g/cm^3,F(000) = 636,GOOF = 1.061,° = 0.115 mm^-1,the final R = 0.0500 and w R = 0.1221 for 3966 observed reflections with I 〉 2σ(I).Both compounds 1 and 2 exhibit 3D supramolecular structures under hydrogen bonding interactions.The results of preliminary antibacterial activity show that the title compounds display moderate antibacterial activities against the tested gram positive bacteria(S.aureus,C.albicans and B.subtilis) and gram negative bacteria(E.coli and P.aeruginosa).
文摘A new method of the multiple rates isotemperature is proposed to define the most probable mechanismg(α) of thermal anlaysis; the iterative isoconversional procedure has been employed to estimate apparent activation energyE; the pre-exponential factorA is obtained on the basis ofE andg(α). By this new method, the thermal analysis kinetics triplet of dehydration of cobalt oxalate dihydrate is determined, apparent activation energyE is 99.84 kJ·mol?1; pre-exponential factorA is 3.427×109–3.872×109 s?1 and the most probable mechanism belongs to nucleation and growth,A m model, the range ofm is from 1.50 to 1.70. Key words multiple rates isotemperature method - isoconversional method - cobalt oxalate dihydrate - accomodation function - differential scanning calorimetry (DSC) CLC number O 636.1 Foundation item: Supported by the Key Foundation of the Science and Technology Committee of Hubei Province (2001ABA009)Biography: Li Li-qing (1977-), female, Master candidate, research direction: material synthesize and thermal analysis kinetics.
基金Financial support by National Natural Science Foundation of China !(Grant No. 29972002) isgreatly acknowledged.
文摘t-Butyldimethylsilyl (TBDMS) ether can be cleaved upon refluxing in acetone/H2O (95 : 5) in the presence of a catalytic amount of copper (II) chloride dihydrate (5 mmol %).
文摘A simple, precise, accurate and sensitive reverse phase high performance liquid chromatographic method for simultaneous estimation of lisinopril dihydrate and its degradation products occuring under different ICH prescribed stress conditions has been modified. Drug was resolved on a C18 column, utilizing modified mobile phase of tetra butyl ammonium hydroxide solution and acetonitrile. Ultra violet detection was carried out at 210 nm. The method was modified with respect to linearity, precision, accuracy, selectivity, specificity and ruggedness. The results obtained revealed that lisinopril dihydrate was an active product slightly changed under stress conditions.
基金supported by the National Key Basic Research Program of China(2013CB933200)the National High-tech R&D Program of China(2012AA062703)+1 种基金Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)the Youth Innovation Promotion Association CAS(2012200)
文摘As a kind of efficient photocatalyst,coordination polymers(CPs) have gained much attention in recent years.However,their safety issue and time-consuming synthesis impede their practical application.Here in this paper we first demonstrate the facile synthesis and photocatalytic degradation performance of 1D α-ferrous oxalate dihydrate(α-FOD),which is one of the simplest CPs.A unique two-pathway photocatalytic mechanism which combines traditional photocatalytic and photo-initiated Fenton oxidations has been proposed.The excellent photocatalytic performance and cost-effective fabrication make α-FOD a new promising candidate for the photocatalytic degradation of organic pollutants in practical applications.
基金Project supported by the Natural Science Foundation of Hebei Province (No. 202140) and Hebei Education Department (No. 2004325).
文摘The thermal decomposition of the magnesium oxalate dihydrate in a static air atmosphere was investigated by TG-DTG techniques. The intermediate and residue of each decomposition were identified from their TG curve. The kinetic triplet, the activation energy E, the pre-exponential factor A and the mechanism functionsf(a) were obtained from analysis of the TG-DTG curves of thermal decomposition of the first stage and the second stage by the Popesou method and the Flynn-Wall-Ozawa method.
基金support from the Research Council of the University of Sistan and Baluchestanthe Australian National University
文摘An efficient green protocol is described for the preparation of highly functionalized piperidines via a one-pot five-component reaction between aromatic aldehydes,anilines andβ-ketoesters in the presence of oxalic acid dihydrate as catalyst in ethanol at ambient temperature.The structure as well as the relative stereochemistry of these compounds was confirmed by single X-ray crystallographic analysis.
文摘The mixture of CaHPO 4·2H 2O and CaCO 3 was ground in an aqueous system under appropriate conditions to investigate the mechanochemical reaction for the synthesis of crystalline hydroxyapatite (HA) powder. Hydroxyapatite of high crystallinity powder including trace Ca 10 (PO 4) 6CO 3(OH) and Ca 9HPO 4(PO 4) 6OH can be synthesized by mechanical activation without further thermal treatment at a high temperature. The synthesis reaction during the grinding process was almost completed within 1h. The as-ground powder exhibits a particle distribution of 20-100nm in size with a spherical or rodlike morphology. The composition and degree of crystallinity of the mechanochemical synthesized hydroxyapatite powders were coincident with the cement-type hydroxyapatite.
基金Project (2003AA302210) supported by the National High Technology Research and Development Program of Chinaproject(04JJ3083) supported by the Elite Foundation of Hunan Province+1 种基金 China project (030615) supported by the Innovation Pro
文摘Electrodeposition technique was used to coat calcium phosphate on carbon fiber which can be used to reinforce hydroxyapatite. The differences between fibers treated with and without nitric acid in electrodeposition were evaluated. The X-ray diffractometry results show that CaHPO4·2H2O is obtained as the kind of calcium phosphate coating on carbon fiber. The scanning electron microscopy photographs and deposit kinetic curve indicate that the influences of the functional group attained by nitric acid treatment, the crystal morphology and crystallization of the coating layers on the fiber with and without treatment rate are obviously different. The functional group, especially the acidic group, can act as nucleation centers of electrochemical crystallization.
基金financial support from the Swedish Innovation Agency(VINNOVA)and China Scholarship Council(CSC).
文摘α-calcium sulfate hemihydrate (α-HH) is known to be suitable for application as bone void filler. High percentage of α-HH is obviously needed for medical applications, especially for implantation. Three commercially available calcium sulfate dihydrates (DH, CaSO4·2H2O) with different sizes and surface morphologies were used as starting materials to synthesize high percentage α-HH via a hydrothermal method. The median particle sizes of the three types of DH were 946.7 μm, 162.4 μm and 62.4 μm, respectively. They were named as DH-L, DH-M and DH-S in this paper. The particle size distribution, morphology and phase composition of the raw materials were evaluated before synthesis. SEM results revealed that DH-L consisted of irregular large particles, while DH-M and DH-S were composed of plate-like particles with some small ones. High percentage HH can be obtained with proper synthesis parameters by hydrothermal method, specifically, 105 °C/90 min for DH-L (achieving 98.8% HH), 105°C/30 min for DH-M (achieving 96.7% HH) and 100°C/45 min for DH-S (achieving 98.4% HH). All the synthesized HH were hexagonal columns, demonstrating that they were α-phase HH. The particle size and morphology of starting material (DH) have significant influences on not only the rate of phase transition but also the morphology of the synthesized α-HH. Calcium sulfate dihydrate cements were prepared by the synthesized α-HH. The highest compressive strength of calcium sulfate dihydrate cement was 17.2 MPa. The results show that the preparation of high percentage α-HH is feasible via a hydrothermal method and the process can be further scaled up to industrial scale production.
文摘Objectives: To define clinical differences in the acute phase response and serum acute phase reactants between gout, pseudogout and crystal-induced arthritis in the presence of non-articular infections (CAI). Patients and Methods: Eleven patients with definite gout, 12 patients with pseudogout and 5 patients with CIA were included in the study. Results: The erythrocyte sedimentation rate (ESR) was significantly different between gout (68.2 ± 49.9 mm/Hr) and CIA (113.8 ± 37.2 mm/Hr) but not between gout and pseudogout (83.9 ± 45.6 mm/Hr) or between pseudogout and CIA. The C-reactive protein (CRP) was significantly increased between gout (10.1 ± 7.9 mg/dL) and pseudogout (18.9 ± 9.8 mg/dL), gout and CIA (36.5 ± 12.4 mg/dL) as well as between pseudogout and CIA. The peripheral white cell count was significantly different between gout (9.27 ± 3.7 k/μL) and CIA (16.5 ± 6.8 k/μL), and between pseudogout (8.9 ± 3.2 k/μL) and CIA. Conclusions: Measurement of ESR and CRP are helpful in crystal-induced arthritis. The CRP has more discriminating utility than the ESR in distinguishing between gout, pseudogout and CIA. Peripheral wbc is most useful for differentiating crystal-induced arthritis from CIA.
基金supported by the National Natural Science Foundation of China(2014AA022103)the Zhejiang Province Public Welfare Technology Application Research Project(LGG20B060003)。
文摘A novel silver-based dihydric alcohol extractant was substituted for ionic liquids to enrich methyl linolenate(C18-3)from tallow seed oil methyl ester in this study.The interactions among dihydric alcohol,Ag(I)and C18-3 were explored by FT-IR spectroscopy.The effects of dihydric alcohol structure,carrier Ag(I)concentration,temperature and initial feed concentration on extraction yield and selectivity were reported.The good extraction performance was achieved by 1,4-butanediol containing AgBF4.The complexation of Ag(I)with C18-3 was dominant in extraction operation rather than physical partition.Furthermore,a multi-step reverse extraction method was proposed to obtain C18-3 product and regenerate the extractant.1-Hexene as the stripping phase can facilitate C18-3 reverse extraction.The content of C18-3 in the product was up to 93.36%,and the yield was 73.76%.This work opened a new route for the utilization of the dihydric alcohol properties to manipulate the carrier efficiency for extracting unsaturated fatty acid methyl esters at a lower cost.
文摘The effect of five dihydric alcohols on the fixation rate and K/S value of reactive dyes on cotton fabrics was investigated.Results show that the more primary hydroxyl groups are contained in the isomeric dihydric alcohols,the greater activity of reacting with the reactive dye.Longer carbon chain also increases the reactivity of dihydric alcohols with reactive dyes.This study provides a theoretical basis for the selection of suitable dihydric alcohols in preparation reactive dye inkjet printing ink.