TG and DTA analysis of Y1−xCaxBa2Cu3O7−y suggests that the stability of the 123 phase increases with increasing Ca contents. The O(1) in the Cu(1)-O chain is unstable
but O(2) and O(3) in Cu(2)-O planes are very stable. There are hardly any oxygen vacancies in the Cu(2)-O plane. The replacement
of Y by Ca does not make oxygen vacancies in Cu(2)-O planes but leads to an increase in the oxidation number of copper in
The complexes of [Sm(o-MOBA)3bipy]2·H2O and [Sm(m-MOBA)3bipy]2·H2O (o(m)-MOBA = o(m)-methoxybenzoic acid, bipy-2,2′-bipyridine) have been synthesized and characterized by elemental analysis, IR, UV, XRD and
molar conductance, respectively. The thermal decomposition processes of the two complexes were studied by means of TG–DTG
and IR techniques. The thermal decomposition kinetics of them were investigated from analysis of the TG and DTG curves by
jointly using advanced double equal-double steps method and Starink method. The kinetic parameters (activation energy E and pre-exponential factor A) and thermodynamic parameters (ΔH≠, ΔG≠ and ΔS≠) of the second-step decomposition process for the two complexes were obtained, respectively.
Authors:H.J. Shi, Z.J. Sun, Z.M. Yan, and J.B. Ren
Temperature uniformity and heating rate subjected to radio frequency (RF) heating have major impact on the quality of treated low moisture foods. The objective of this paper was to analyse the influence of electrode distance on the heating behaviour of RF on condition that the sample shape, size, and location between the electrodes were defined. Considering peanut butter (PB) and wheat flour (WF) as sample food, a 3D computer simulation model was developed using COMSOL, which was experimentally validated by a RF machine (27.12 MHz, 6 kW). Specifically, the electrode distances were selected as 84, 89, 93, 99 and 89, 93, 98, 103 (mm) for RF heating of PB and WF, respectively. Results showed that the simulated results and experimental data agreed well; the temperature-time histories of the RF heating of PB and WF were approximate straight lines; both the temperature uniformity index and the heating rate decreased with the increase of the electrode distance; the heating rate had a negative logarithmic linear relationship with the electrode distance, which was independent of the types, geometry shapes and sizes of low moisture foods.
Authors:A. Ren, S. Yu, J. Han, P. Chang, C. Chen, J. Chen, and X. Wang
Humic substances have attracted great interest in the investigation of metal ion behavior in the environment because of their
special properties. Sorption and complexation of Pb2+ on MX-80 bentonite, LA bentonite, alumina and silica as a function of pH were studied in the presence and absence of fulvic
acid (FA). The experiments were carried out in 0.01M and 0.001M NaNO3 solutions under ambient conditions. The results indicate that sorption of Pb2+ on the solid samples is strongly dependent on pH and FA. The sorption of Pb2+ is not influenced drastically by ionic strength. The nature of minerals/oxides, nature of humic substances and the composition
of the solution are important factors in the behavior of metal ions in the environment. The results also indicate that FA
has a positive effect on Pb2+ sorption at low and a negative effect at high pH values, and the results are discussed in the comparative complexation between
FA-Pb2+ and Pb2+-minerals.
Authors:J. Zhou, Z. Yang, J. Feng, X. Zhang, G. Li, and Z. Ren
plays an important role in wheat improvement. Here we report a new triticale, named Fenzhi-1, derived from the wide cross MY11
after the in vitro rye pollen has been irradiated by He-Ne laser. Morphologically, Fenzhi-1 is characterized by branched-spikes. Genetically, Fenzhi-1 displays stable fertility and immunity to wheat powdery mildew and stripe rust. In situ hybridization (FISH) and seed storage protein electrophoresis revealed that Fenzhi-1 is a new primary hexaploid triticale (AABBRR). The present study not only provides a new method to synthesize an artificial species, but also shows that Fenzhi-1 could be a valuable source for wheat improvement.
Authors:C. Liu, Z. Yang, J. Jia, G. Li, J. Zhou, and Z. Ren
Knowledge of the chromosomal distribution of long terminal repeats (LTR) is important for understanding plant chromosome structure, genomic organization and evolution, as well as providing chromosomal landmarks that are useful for chromosome engineering. The aim of this study is to investigate the genomic distribution of
-like LTR pDbH12, which was first isolated from
species in relation to the genomic evolution and chromosome identification. Fluorescence
hybridization (FISH) analysis showed that pDbH12 is present on
(V genome) and
(H genome) species with the hybridized signals covering the entire chromosomes. However, clone pDbH12 did not hybridize to the genomes of
Secale, Triticum, Lophopyrum, Pseduoroengeria, Aegilops, Agropyron desertorum
Elymus. Thinopyrum intermedium
displayed fourteen chromosomes that hybridized with pDbH12. Sequential FISH identified these chromosomes as belonging to the J
genome. Results from sequence characterized amplified region (SCAR) marker and dot blot both support the FISH results, and the integrative results suggest that amplification of
-like LTR retrotransposons is an important factor which involved in the speciation process. Clone pDbH12 could serve as a cytogenetic marker for tracing chromatin from V or V
, H and J
genomes in wheat-alien introgression lines.
Authors:S. Yu, A. Ren, J. Cheng, X. Song, C. Chen, and X. Wang
Effects of pH, ionic strength and fulvic acid on sorption of radiocobalt on montmorillonite and its Al-pillared and cross-linked
samples were studied using batch technique. The results indicate that the sorption of cobalt is strongly dependent on pH values
and independent of ionic strength. Fulvic acid enhances the sorption of cobalt slightly at low pH, but has no influence at
high pH values. Surface complexation is considered the main mechanism of cobalt sorption to montmorillonite. The sequences
of FA/Co2+ additions to the system did not affect cobalt sorption.
Authors:H. Ye, N. Ren, H. Li, J. Zhang, S. Sun, and L. Tian
The complex of [Nd(BA)3bipy]2 (BA = benzoic acid; bipy = 2,2′-bipyridine) has been synthesized and characterized by elemental analysis, IR spectra, single
crystal X-ray diffraction, and TG/DTG techniques. The crystal is monoclinic with space group P2(1)/n. The two–eight coordinated Nd3+ ions are linked together by four bridged BA ligands and each Nd3+ ion is further bonded to one chelated bidentate BA ligand and one 2,2′-bipyridine molecule. The thermal decomposition process
of the title complex was discussed by TG/DTG and IR techniques. The non-isothermal kinetics was investigated by using double
equal-double step method. The kinetic equation for the first stage can be expressed as dα/dt = A exp(−E/RT)(1 − α). The thermodynamic parameters (ΔH≠, ΔG≠, and ΔS≠) and kinetic parameters (activation energy E and pre-exponential factor A) were also calculated.
Authors:S. Xiao, J. Zhang, X. Li, L. Ye, H. Gu, and N. Ren
A ternary binuclear complex of dysprosium chloride hexahydrate with m-nitrobenzoic acid and 1,10-phenanthroline, [Dy(m-NBA)3phen]2·4H2O (m-NBA: m-nitrobenzoate; phen: 1,10-phenanthroline) was synthesized. The dissolution enthalpies of [2phen·H2O(s)], [6m-HNBA(s)], [2DyCl3·6H2O(s)], and [Dy(m-NBA)3phen]2·4H2O(s) in the calorimetric solvent (VDMSO:VMeOH = 3:2) were determined by the solution–reaction isoperibol calorimeter at 298.15 K to be