In an ongoing effort to understand the thermodynamic properties of proteins, ovalbumin, lactoglobulin, lysozyme are studied
by adiabatic and differential scanning calorimetry over wide temperature ranges. The heat capacities of the samples in their
pure, solid states are linked to an approximate vibrational spectrum with the ATHAS analysis that makes use of known group
vibrations and a set of parameters, Θ1 and Θ3, of the Tarasov function for the skeletal vibrations. Good agreement is found between experiment and calculation with rms
errors mostly within ±3%. The analyses were also carried out with an empirical addition scheme using data from polypeptides
of naturally occurring amino acids. Due to space limitation, only selected results are reported.
Chlorophyll content is positively correlated with photosynthetic rate. However, little is known about the genetic correlation between grain yield and chlorophyll content in the same wheat mapping population. The primary goal of the study was to detect the genetic basis of grain yield and chlorophyll content and their possible roles in the genetic improvement of grain yield in wheat. Here, quantitative trait loci (QTLs) for grain yield and chlorophyll content were studied using a set of 168 doubled haploid (DH) lines derived from a cross between two elite Chinese wheat cultivars, Huapei 3×Yumai 57. The DH population and parents were evaluated for grain yield and chlorophyll content in three environments. A total of 11 additive QTLs and 6 pairs of epistatic QTLs were detected for grain yield and chlorophyll content. Loci, such as
on chromosomes (e.g. 2D, 4A, and 5D) simultaneously controling grain yield and chlorophyll content, showed tight linkages or pleiotropisms. Three novel major QTLs,
, closely linked with the PCR marker
on chromosome 5D, accounted for 10.32%, 12.95%, and 23.29% of the phenotypic variance, respectively. The favorable alleles came from Yumai 57.
The concept of crystallization dynamics method evaluating the miscibility of binary blend system including crystalline component
was proposed. Three characteristic rates, nucleation, crystal growth rates (N*, G*) and growth rate of conformation (Gc*) were used to evaluate the miscibility of PVDF/at-PMMA and PVDF/iso-PMMA by the simultaneous DSC-FTIR. N*, G* and Gc* depended remarkably on both temperature and blend fraction (ϕPMMA) for PVDF/at-PMMA system, which indicated the miscible system. PVDF/iso-PMMA showed small ϕPMMA dependency of N*, G* and Gc*, was estimated the immiscible system. The ΔT/Tm0 values, corresponding to Gibbs energy required to attend the constant G* and Gc*, evaluated from G* and Gc* showed the good linear relationships with different slope. The experimental results suggested that the concentration fluctuation
existed in PVDF/iso-PMMA system.
The crystallization dynamics of Nylon 66/Nylon 6
blends, the crystalline/crystalline polymer blends, was analyzed by DSC under
isothermal conditions. The crystal growth rate (G)
and the nucleation rate (N) depended on
both the degree of supercooling (ΔT)
and the blend mass fraction (ϕ). The ΔT
values obtained at the fixed G, which corresponded
to the chemical potential difference of molecules between liquid and crystal
states, and the surface free energy parameters evaluated from G
and N depended on ϕ for blends. The
results suggested that Nylon 66/Nylon 6 blends with ϕN66≥0.80
or ϕN66≤0.15 are miscible.
The relationship between plant communities and elevation in the Guandi mountainous area was studied. Data from 89 sampling units, each of 10 m x 20 m size, taken along an elevation gradient were analyzed by TWINSPAN, DECORANA and diversity and evenness indices. The samples were clustered into 23 groups by TWINSPAN, representing 23 vegetation types. The composition and distribution of communities varied greatly along the altitude gradient, suggesting that community diversity is closely related to elevation in the Guandi Mountains. This is due to the change of temperature and water-conditions along the elevation gradient. Species heterogeneity and evenness were significantly correlated with elevation along the entire gradient, but showing first a trend of increases and then decreases, corresponding to the hypothesis of maximum diversity at medium elevation. Species richness varied greatly in the study area, and was not significantly correlated with elevation.
Authors:X. Zhang, Y. Ding, Y. Zhang, Y. Hao, G. Meng, and L. Zhang
Highly oriented single crystal antimony nanowire arrays have been synthesized within anodic aluminum oxide (AAO) template
by pulsed electrodeposition. Thermal behavior and oxidation analysis of the antimony nanowires have been investigated by means
of thermogravimetry and differential scanning calorimetry in Ar and air atmosphere, respectively. Compared to bulk antimony,
the antimony nanowires exhibit a lower sublimation temperature at 496.4°C. Evident oxidation of the Sb nanowires occurs at
429.8°C in air atmosphere and α-Sb2O4 nanowires have been obtained as the oxidation product. The results indicate that the sublimation and the oxidation of the
antimony nanowires in the AAO template is a slow multi-step process. The present results are of relevance when processing
antimony nanowries for thermoelectric applications at high temperatures.
Authors:G. Xu, L. Zhang, L. Liu, G. Liu, and D. Jia
Thermal behaviors of two mixed-ligand complexes, [Ni(PMPP-SAL)(Py)3] and [Cu(PMPP-SAL)Py]·MeOH, (PMPP-SAL=1-phenyl-3-methyl-4-(salicylidene hydrazide)-propenylidene-pyrazolone-5, Py=pyridine),
were studied by TG-DTG-DTA in dynamic air atmosphere. The complexes show the loss of pyridine molecule is followed by the
decomposition of the PMPP-SAL anion and give respective metal oxides as residues. Meanwhile, the Ozawa-Flynn-Wall model-free
analyses and multivariate non-linear regressions were applied to perform single and overall steps optimization. Kinetic parameters
were given and the most probable mechanism functions were suggested in this study.
Authors:L. Lv, L. Zhao, X. Wang, H. Zhang, Z. Zhu, Y. Chai, and G. Zhang
Epimedium pubescens Maxim. and Epimedium koreanum Nakai. are two common and confused species of Herba Epimedii in Chinese Pharmacopoeia 2010 edition. Different species and growing conditions lead to chemical differences between the two species which may result in the improper clinical usage. In this work, a new method based on rapid-resolution liquid chromatography combined with time-of-flight mass spectrometry (RRLC/TOFMS) has been developed for identification and differentiation of major flavonoids in two kinds of Epimedium extract and rat plasma. The compounds were identified effectively based on the accurate extract masses and formulae acquired by RRLC/TOFMS. The fragmentation rules deduced by collision-induced dissociation (CID) were successfully implemented in distinguishing some of the isomers, further validating the results. By using the combined analytical techniques, a total of 40 major flavonoids in extracts of two kinds of Epimedium were identified within 30 min, including 31 common components and 9 characteristic components. After oral administration, three prototype compounds in rat plasma were detected by comparing the constituents measured in vitro with those in vivo, and five metabolites were identified by contrasting the fragmentation rules. The identification and structural elucidation of the chemical constituents provided essential data for further pharmacological and clinical studies on different species of Epimedium.
A series of UO22+ complex with monoamide ligand was isolated. The complexes have been characterized with the aid of 13C and 1HNMR spectroscopic studies. The result shows that the amide ligand directly coordinates to the uranyl(VI) ion through its carbonyl group. The change of the value of the chemical shift due to the complexation has been discussed.
Authors:G. Zhang, T. Kitamura, H. Yoshida, and T. Kawai
The simultaneous DSC-FTIR was used for the observation of crystallization and melting of poly(vinylidene fluoride) (PVDF)
and its blends with poly(methyl methacrylate) (PMMA) and poly(ethyl methacrylate) (PEMA). The isothermal crystallization was
carried out under the condition of both α-form and γ-form crystallized competitively. The crystal growth rate of α -form and
γ -form were evaluated from the absorbance changes at 795 cm-1 (α -form, CH2 rocking) and 810 cm-1 (γ -form, CH2 rocking) obtained by the DSC-FTIR. The crystal growth rate of γ -form decreased at the same crystallization temperature in
the order of PVDF/syn-PMMA, PVDF/PEMA and PVDF/at-PMMA, which was corresponding to the order of interaction parameter. The mechanism of α -g transition of PVDF in the miscible
blends with at-PMMA, syn-PMMA and PEMA was evaluated from the relationship between the decrease of α -form and the increase of γ -form. The critical
crystallization temperature, at which the transformation from α -form to γ -form proceeded only in the solid state, shifted
to higher temperature side in the order of interaction parameter.