Takotsubo cardiomyopathy (TTC) is a rare condition that affects mainly aging women. According to a retrospective review, patients with TTC accounted for approximately 2% of all the patients with suspected acute coro...Takotsubo cardiomyopathy (TTC) is a rare condition that affects mainly aging women. According to a retrospective review, patients with TTC accounted for approximately 2% of all the patients with suspected acute coronary syndrome (ACS). A few reports indicated that the average age of TTC patients was 68 years, although children or young adults may also be affected. In US and Europe, a number of contemporary TTC studies report that 90% of patients with TTC are women aged 65-70 years. Meta analysis showed that the age ranged from 10 to 89 years.展开更多
Several 1,4-benzenedicarbonyl thiourea resins (BTR) were synthesized through interfacial polymerization between 1,4- benzenedicarbonyl diisothiocyanate and polyamine. Their structures were confirmed by FT-IR. The ad...Several 1,4-benzenedicarbonyl thiourea resins (BTR) were synthesized through interfacial polymerization between 1,4- benzenedicarbonyl diisothiocyanate and polyamine. Their structures were confirmed by FT-IR. The adsorption properties (including the effect of adsorption time, pH, initial concentrations and temperature) of BTR-1, BTR-2 and BTR-3 for Ag(I) were investigated by batch tests. The results show that the adsorption equilibria of BTR-1, BTR-2, BTR-3 for Ag(I) are achieved after about 10 h. Their equilibrium adsorption capacities are 7.11, 6.75 and 6.23, respectively, and the adsorption process accords with G. E. Boyd equation and Langmuir adsorption isotherm as well. The adsorption capacities increase with the increase ofpH (the highest uptake values are observed at pH being about 6-7). The thermodynamic parameters of BTR-1 were calculated. The results show that ΔH^ and ΔS^ are 6 958.8 J/mol and 64.28 J/(mol.K), respectively, and ΔG^ at 20, 30, 40 and 50 ℃ are -11.79, -12.52, -13.16 and -13.8 kJ/mol, respectively. The silver-loaded resins can be quantitatively eluted by a solution containing 6% thiourea in 1 mol/L HNO3.展开更多
Synthesis of composite oxides in the series Nd4-xCs2(1+x)Fe5-xZnxO14+δ(0≤x≤1.0) (B1-B5: x= 0.0, 0.25, 0.5, 0.75, 1.0) is performed by sol-gel method via nitrate-acetate precursor route. Analysis of the pow...Synthesis of composite oxides in the series Nd4-xCs2(1+x)Fe5-xZnxO14+δ(0≤x≤1.0) (B1-B5: x= 0.0, 0.25, 0.5, 0.75, 1.0) is performed by sol-gel method via nitrate-acetate precursor route. Analysis of the powder x-ray diffraction (XRD) patterns show tetragonal unit cell with lattice parameters a = 8.6545, 8.2520, 7.7645, 9.8952, 8.2863 A; b = 8.9800, 11.5788, 15.6305, 8.4766, 11.6465 A in B1-B5, respectively. The average crystallite sizes in the samples are found to be in the range 69.56-119.48 A. Energy dispersive analysis of x-rays (EDAX) result shows the presence of Fe, Nd, Cs and O, and Fe, Nd, Zn, Cs and O in B 1 (x=0) and B2(x=0.25)-B5(x= 1.0), respectively. The IR results at 300 K show the presence of octahedral [NdO6/2]^3- (asymmetric stretch: 410-416 cml) and [FeO6/2]^3-(symmetric stretch: 562-572 cm^-1) units in the samples. Observed magnetic moments versus magnetic field plots in the range -10 kG to +10 kG exhibit hysteresis loops with average magnetic susceptibility values in the range 3.46 × 10^-5 -7.05 × 10^-5 emu/gG in B1-B5 shows fairly strong ferromagnetic nature of the samples. The observed EPR lineshapes at 300 and 77 K with giso=2.01-2.03 and giso=2.01-2.03, respectively is ascribed to the octahedral [FeO6/2]^3- coordination of Fe^3+ (3d^5) ion. The optical absorption spectra show the transition of ^4I9/2→^4F7/2→^ 4S3/2 (750 nm) of optically active Nd^3+ ions in samples.展开更多
Pristine GeTe shows inferior thermoelectric performance around unit due to the large carrier concentration induced by the presence of intrinsic high concentration of Ge vacancy. In this study, we report a thermoelectr...Pristine GeTe shows inferior thermoelectric performance around unit due to the large carrier concentration induced by the presence of intrinsic high concentration of Ge vacancy. In this study, we report a thermoelectric figure of merit ZT of 1.56 at 700 K, realized in Sb-doped GeTe based thermoelectric(TE)materials via combined effect of suppression of intrinsic Ge vacancy and Sb doping. The nonequilibrium nature during melt spinning process plays very important role. For one thing, it promotes the homogeneity in Ge_(1-x)Sb_xTe samples and refines the grain size of the product. Moreover the persistent Ge precipitated as impurity phase in the traditional synthesis process is found to be dissolved back into the GeTe sublattice, accompanying with a drastic suppression of Ge vacancies concentration which in combination with Sb electron doping significantly reduced the inherent carrier concentration in GeTe.Low carrier concentration, approaching the optimum carrier concentration ~3.74 × 10^(-20) cm^(-3) and a high power factor of 4.01 × 10^(-3) W m^(-1)K^(-2) at 750 K are achieved for Ge_(0.98)Sb_(0.02) Te sample. In addition,the enhanced grain boundary phonon scattering by refining the grain size through melt spinning(MS)process, coupled with the intensified alloying phonon scattering via Sb doping leads to low thermal conductivity of 1.53 W m^(-1) K^(-1) at 700 K for Ge_(0.94) Sb_(0.06) Te sample. All those contribute to a high ZT value,representing over 50% improvement in the ZT value compared to the Sb free samples, which provides an alternative way for ultrafast synthesis of high performance GeTe based thermoelectric material.展开更多
To develop the high-performance fluorescent bio-sensors, the metal nanoparticles were employed as nanoquenchers and at- tracted reasonable attention in the design of fluorescent biosensors. In this work, silver nanopa...To develop the high-performance fluorescent bio-sensors, the metal nanoparticles were employed as nanoquenchers and at- tracted reasonable attention in the design of fluorescent biosensors. In this work, silver nanoparticles (AgNPs) were obtained via reduction of Ag+ on FAM-labeled DNA template. For the tight binding between AgNPs and DNA, the tem- plate-synthesized AgNPs turned out high quenching efficiency and could be applied as super nanoquenchers to establish the biosensing platform for fluorescent detection. As an example, the template-synthesized DNA-AgNPs conjugates were em- ployed in sensing thiols. By forming S-Ag bonds, thiols interact intensely with AgNPs and replace the FAM-labeled DNA off from the surface of AgNPs, resulting in a fluorescence enhancement. Besides the advantages of lower background and higher signal-to-background ratio (S/B), the conjugates present better stability, making them applicable in complicated biological fluids. To further evidence the feasibility of sensing thiols in real samples, the thiols in human urine were detected. The total amount of free thiols found in human urine was ranging from 229 μM to 302μM with the proposed sensor. To conclude the reliability, low content of Cys was added and the recovery was 98%-103%.展开更多
文摘Takotsubo cardiomyopathy (TTC) is a rare condition that affects mainly aging women. According to a retrospective review, patients with TTC accounted for approximately 2% of all the patients with suspected acute coronary syndrome (ACS). A few reports indicated that the average age of TTC patients was 68 years, although children or young adults may also be affected. In US and Europe, a number of contemporary TTC studies report that 90% of patients with TTC are women aged 65-70 years. Meta analysis showed that the age ranged from 10 to 89 years.
基金Projects(20476105, 50604016) supported by the National Natural Science Foundation of China
文摘Several 1,4-benzenedicarbonyl thiourea resins (BTR) were synthesized through interfacial polymerization between 1,4- benzenedicarbonyl diisothiocyanate and polyamine. Their structures were confirmed by FT-IR. The adsorption properties (including the effect of adsorption time, pH, initial concentrations and temperature) of BTR-1, BTR-2 and BTR-3 for Ag(I) were investigated by batch tests. The results show that the adsorption equilibria of BTR-1, BTR-2, BTR-3 for Ag(I) are achieved after about 10 h. Their equilibrium adsorption capacities are 7.11, 6.75 and 6.23, respectively, and the adsorption process accords with G. E. Boyd equation and Langmuir adsorption isotherm as well. The adsorption capacities increase with the increase ofpH (the highest uptake values are observed at pH being about 6-7). The thermodynamic parameters of BTR-1 were calculated. The results show that ΔH^ and ΔS^ are 6 958.8 J/mol and 64.28 J/(mol.K), respectively, and ΔG^ at 20, 30, 40 and 50 ℃ are -11.79, -12.52, -13.16 and -13.8 kJ/mol, respectively. The silver-loaded resins can be quantitatively eluted by a solution containing 6% thiourea in 1 mol/L HNO3.
文摘Synthesis of composite oxides in the series Nd4-xCs2(1+x)Fe5-xZnxO14+δ(0≤x≤1.0) (B1-B5: x= 0.0, 0.25, 0.5, 0.75, 1.0) is performed by sol-gel method via nitrate-acetate precursor route. Analysis of the powder x-ray diffraction (XRD) patterns show tetragonal unit cell with lattice parameters a = 8.6545, 8.2520, 7.7645, 9.8952, 8.2863 A; b = 8.9800, 11.5788, 15.6305, 8.4766, 11.6465 A in B1-B5, respectively. The average crystallite sizes in the samples are found to be in the range 69.56-119.48 A. Energy dispersive analysis of x-rays (EDAX) result shows the presence of Fe, Nd, Cs and O, and Fe, Nd, Zn, Cs and O in B 1 (x=0) and B2(x=0.25)-B5(x= 1.0), respectively. The IR results at 300 K show the presence of octahedral [NdO6/2]^3- (asymmetric stretch: 410-416 cml) and [FeO6/2]^3-(symmetric stretch: 562-572 cm^-1) units in the samples. Observed magnetic moments versus magnetic field plots in the range -10 kG to +10 kG exhibit hysteresis loops with average magnetic susceptibility values in the range 3.46 × 10^-5 -7.05 × 10^-5 emu/gG in B1-B5 shows fairly strong ferromagnetic nature of the samples. The observed EPR lineshapes at 300 and 77 K with giso=2.01-2.03 and giso=2.01-2.03, respectively is ascribed to the octahedral [FeO6/2]^3- coordination of Fe^3+ (3d^5) ion. The optical absorption spectra show the transition of ^4I9/2→^4F7/2→^ 4S3/2 (750 nm) of optically active Nd^3+ ions in samples.
基金supported by the National Natural Science Foundation of China(51402222,51521001,and 51632006)the 111 Project of China(B07040)
文摘Pristine GeTe shows inferior thermoelectric performance around unit due to the large carrier concentration induced by the presence of intrinsic high concentration of Ge vacancy. In this study, we report a thermoelectric figure of merit ZT of 1.56 at 700 K, realized in Sb-doped GeTe based thermoelectric(TE)materials via combined effect of suppression of intrinsic Ge vacancy and Sb doping. The nonequilibrium nature during melt spinning process plays very important role. For one thing, it promotes the homogeneity in Ge_(1-x)Sb_xTe samples and refines the grain size of the product. Moreover the persistent Ge precipitated as impurity phase in the traditional synthesis process is found to be dissolved back into the GeTe sublattice, accompanying with a drastic suppression of Ge vacancies concentration which in combination with Sb electron doping significantly reduced the inherent carrier concentration in GeTe.Low carrier concentration, approaching the optimum carrier concentration ~3.74 × 10^(-20) cm^(-3) and a high power factor of 4.01 × 10^(-3) W m^(-1)K^(-2) at 750 K are achieved for Ge_(0.98)Sb_(0.02) Te sample. In addition,the enhanced grain boundary phonon scattering by refining the grain size through melt spinning(MS)process, coupled with the intensified alloying phonon scattering via Sb doping leads to low thermal conductivity of 1.53 W m^(-1) K^(-1) at 700 K for Ge_(0.94) Sb_(0.06) Te sample. All those contribute to a high ZT value,representing over 50% improvement in the ZT value compared to the Sb free samples, which provides an alternative way for ultrafast synthesis of high performance GeTe based thermoelectric material.
基金supported by the National Natural Foundation of China (21075032 & 21005026)National Key Basic Research Program (2011CB911000)Hunan Province Key Project of Scientific & Tech-nical Programs (2010TP4013-1)
文摘To develop the high-performance fluorescent bio-sensors, the metal nanoparticles were employed as nanoquenchers and at- tracted reasonable attention in the design of fluorescent biosensors. In this work, silver nanoparticles (AgNPs) were obtained via reduction of Ag+ on FAM-labeled DNA template. For the tight binding between AgNPs and DNA, the tem- plate-synthesized AgNPs turned out high quenching efficiency and could be applied as super nanoquenchers to establish the biosensing platform for fluorescent detection. As an example, the template-synthesized DNA-AgNPs conjugates were em- ployed in sensing thiols. By forming S-Ag bonds, thiols interact intensely with AgNPs and replace the FAM-labeled DNA off from the surface of AgNPs, resulting in a fluorescence enhancement. Besides the advantages of lower background and higher signal-to-background ratio (S/B), the conjugates present better stability, making them applicable in complicated biological fluids. To further evidence the feasibility of sensing thiols in real samples, the thiols in human urine were detected. The total amount of free thiols found in human urine was ranging from 229 μM to 302μM with the proposed sensor. To conclude the reliability, low content of Cys was added and the recovery was 98%-103%.