Authors:J. Wang, Z. Yan, Y. Zheng, W. Cao, and Y. Wei
Fructose-bisphosphate aldolase (FBA, EC 126.96.36.199) catalyzes an aldol cleavage of fructose-1, 6-bisphosphate to dihydroxyacetone-phosphate and glyceraldehyde 3-phosphate and a reversible aldol condensation. Three candidate genes with 1077bp coding for fructose-bisphosphate aldolase were cloned and sequenced in wheat, barley and rye. These genes could encode 358 amino acid residues. Sequence analysis indicated that wheat, barley and rye FBA genes were conserved with high identity (94.13%), while maize sequence had a 9bp deletion near the 3’ terminal. According to the alignment of 75 amino acid sequences, conserved domains of the FBAs were detected. These conserved domains might be the important functional sites of the FBAs. The cytoplasmic FBAs of wheat, barley and rye were clustered together, and the cluster was close to maize and rice FBAs. Nine peptides of the FBAs and the last amino acid Tyr (necessary for preference for fructose 1,6-bisphosphate over fructose 1-phosphate) were most conserved in plants, animals and algae. Current findings suggested that the FBAs could be divided into three main subgroups: plant cytoplasmic FBA, plant chloroplastic FBA and animal FBA. These results also indicated that the active and binding sites of FBAs had rare variations during the long-term evolution.
Authors:X. Cao, Z. Wang, X. Yang, Y. Liu, and C. Wang
The kinetics of protein thermal transition is of a significant interest from the standpoint of medical treatment. The effect
of sucrose (0–15 mass%) on bovine serum albumin denatured aggregation kinetics at high concentration was studied by the iso-conversional
method and the master plots method using differential scanning calorimetry. The observed aggregation was irreversible and
conformed to the simple order reaction. The denaturation temperature (Tm), the kinetic triplets all increased as the sucrose concentration increased, which indicated the remarkable stabilization
effect of sucrose. The study purpose is to provide new opportunities in exploring aggregation kinetics mechanisms in the presence
Authors:J. Zeng, Z. Cao, D. Yang, L. Sun, and L. Zhang
One of the greatest challenges in the application of organic phase change materials (PCMs) is to increase their thermal conductivity
while maintaining high phase change enthalpy. 1-Tetradecanol/Ag nanowires composite PCM containing 62.73 wt% (about 11.8 vol%)
of Ag nanowires showed remarkably high thermal conductivity (1.46 W m−1 K−1) and reasonably high phase change enthalpy (76.5 J g−1). This behavior was attributed to the high aspect ratio of Ag nanowires, few thermal conduct interfaces, and high interface
thermal conductivity of Ag nanowires in the composite PCM. These results indicated that Ag nanowires might be strong candidates
for thermal conductivity enhancement of organic PCMs.
Authors:J. Zeng, Y. Liu, Z. Cao, J. Zhang, Z. Zhang, L. Sun, and F. Xu
We prepared PANI/tetradecanol/MWNTs composites via in-situ polymerization. DSC results indicated that the composites are good
form-stable phase change materials (PCMs) with large phase change enthalpy of 115 J g−1. The MWNTs were randomly dispersed in the composites and significantly enhanced the thermal conductivity of the PCMs from
0.33 to 0.43 W m−1 K−1. The form-stable PCMs won’t liquefy even it is heated at 80°C, so that the MWNTs were fixed in the composite and the phase
separation of the MWNTs from PANI/tetradecanol/MWNTs composites won’t occur.
Authors:J. Zeng, J. Zhang, Y. Liu, Z. Cao, Z. Zhang, F. Xu, and L. Sun
Polyaniline (PANI)/1-tetradecanol (TD) composite materials, a kind of novel composite that can conduct electricity and store
thermal energy at the same time, thus possess the ability to endure certain heat shock, were prepared for the first time.
FTIR and XRD results showed that there were some interactions existed between PANI and TD. The thermal stability of the composites
exhibited both the characteristics of PANI and TD. The DSC experiments showed that the highest phase change enthalpy of the
composites could be as 73% as that of TD, indicating it was a good form-stable phase change material. The thermal conductivity
of the composites was also improved. The AC (Alternating Current) conductivity of the composites was enhanced to close to
that of PANI when the mass fraction of PANI in the composite was increased to 46%. Heat shock experiments showed that the
heat shock resistibility of the composite was greatly improved comparing to that of pure PANI.
Authors:Z. Xiao, D. Liu, C. Wang, Z. Cao, X. Zhan, Z. Yin, Q. Chen, H. Liu, F. Xu, and L. Sun
The effect of mechanical alloying on Zn-Sb alloy system is investigated with X-ray diffraction (XRD), laser grain size analysis
and differential scanning calorimetry (DSC) respectively. The results of laser particle size analysis shows that the particle
size decreases with increasing of the grinding time between 0 and 24 h. XRD and DSC results indicate that longer the grinding
time of Zn-Sb is, the more content of Zn4Sb3 become in the product in this process.
Authors:Z. Chen, S. Wang, J. Tang, X. Li, C. Liu, X. Xu, and G. Cao
To provide a convenient and facile method to evaluate the radiochemical purity (RCP) of 99mTc-TRODAT-1 in quality control of routine clinical application, a simplified method of single-strip thin layer chromatography
(TLC) was developed and validated by high performance liquid chromatography (HPLC). The RCP data of TLC correlated well with
Authors:J. Zeng, Z. Cao, D. Yang, F. Xu, L. Sun, L. Zhang, and X. Zhang
A series of PA-TD mixtures were prepared and their thermal properties were studied by DSC and thermal conductivity measurement.
The phase diagram of the binary system was constructed, which showed an eutectic behavior for the solid-liquid equilibrium
line. The eutectic composition of the binary system was at the mass fraction of TD near 0.7 with an eutectic temperature of
about 29°C. At TD side, PA was partially miscible in the TD solid matrix and the solid phase transition of TD had an effect
on the solidus line. The eutectic composition mixture could be viewed as a new phase change material with large thermal energy
Authors:J. Zeng, Z. Cao, D. Yang, F. Xu, L. Sun, X. Zhang, and L. Zhang
The effects of multi-walled carbon nanotubes (MWNTs) on the phase change enthalpy (ΔH) and the thermal conductivity (κ) of a solid-liquid phase change materials (PCM), palmitic acid (PA), have been investigated.
The results showed that both the ΔH and the κ of the composite were lower than that of PA when the loading of MWNTs was small. As the concentration of MWNTs
in the composites increased, the ΔH of the composites was slightly improved and then decreased linearly. However, the κ of the composites was monotonously increased
from the minimum value. When the loading of MWNTs increased to 5% and no surfactant was added, the κ of the composite was
enhanced to be 26% higher than that of PA. The κ of the composite could be enhanced by CTAB instead of SDBS when the loading
of MWNTs was small, as SDBS showed no obvious effect on the κ of the composites. Furthermore, the effects of surface modification
of MWNTs on the ΔH and the κ of the composites have also been investigated.
Authors:Y. Duan, J. Li, X. Yang, X. Cao, L. Hu, Z. Wang, Y. Liu, and C. Wang
The thermal decomposition of strontium acetate hemihydrate has been studied by TG-DTA/DSC and TG coupled with Fourier transform
infrared spectroscopy (FTIR) under non-isothermal conditions in nitrogen gas from ambient temperature to 600°C. The TG-DTA/DSC
experiments indicate the decomposition goes mainly through two steps: the dehydration and the subsequent decomposition of
anhydrous strontium acetate into strontium carbonate. TG-FTIR analysis of the evolved products from the non-oxidative thermal
degradation indicates mainly the release of water, acetone and carbon dioxide. The model-free isoconversional methods are
employed to calculate the Ea of both steps at different conversion α from 0.1 to 0.9 with increment of 0.05. The relative constant apparent Ea values during dehydration (0.5<α<0.9) of strontium acetate hemihydrate and decomposition of anhydrous strontium acetate (0.5<α<0.9)
suggest that the simplex reactions involved in the corresponding thermal events. The most probable kinetic models during dehydration
and decomposition have been estimated by means of the master plots method.