Raw chemicals such as metal nitrates and chlorides were found to affect the thermal decomposition behaviour of EDTA-gel precursors
used for the production of ceramic powders. Fine, homogeneous ceramic powders were produced from nitrate solutions while chlorides
gave segregated phases. In studies on the production of lead zirconate titanate (PZT) using chlorides, the segregation and
loss of lead was observed and shown to be caused by the formation and evaporation of PbCl2. Thermal analysis (DTA/TG) quantitatively proved the suggested reaction mechanism for this phase segregation. Crystallization
of the desired perovskite phase of lead zirconate titanate (PZT) and barium titanate (BT) initiated at temperatures as low
as 250°C in the nitrate-EDTA precursors. Water of crystallization and formation of BaCO3 in the barium titanate precursor were suggested to account for differences in the observed decompositional behaviours of
the BT and PZT precursors.
Lead zirconate titanate (PZT) ceramic powder has been synthesized from metal nitrate solutions using the EDTA-gel method with
different nitric acid/EDTA ratios. It was found that the thermal decomposition of the precursor was strongly affected by the
nitric acid/EDTA ratio, the amount of sample, the atmosphere, and the heating rate. Crystallization of the perovskite PZT
phase initiated at external temperatures as low as 250°C, as a result of the exothermic decomposition reaction of the nitrate-EDTA
complexes. Possible reaction schemes are suggested and discussed to describe the thermal decomposition of PZT-EDTA precursors
under different experimental conditions.
Authors:F. Cui, J. Li, A. Ding, C. Zhao, X. Li, D. Feng, X. Wang, L. Wang, and H. Wang
To comprehensively understand the genetic basis of plant height (PH), quantitative trait locus (QTL) analysis for internode lengths, internode component indices and plant height component index (PHCI) were firstly conducted in the present study. Two related F8:9 recombinant inbred line (RIL) populations comprising 485 and 229 lines were used. Two hundred and nine putative additive QTL for the eight traits were identified, 35 of which showed significance in at least three trials. Of these, at least 11 pairwise QTL were common to the two populations. PH components at the QTL level had different effects on PH, confirming our previous multivariate conditional analysis (Cui et al. 2011). Eleven major QTL that showed consistency in expression across environments should be of great value in the genetic improvement of PH in wheat. The results above will enhance the understanding of the genetic basis of PH in wheat.
Authors:L. Wang, F. Cui, A. Ding, J. Li, J. Wang, C. Zhao, X. Li, D. Feng, and H. Wang
A recombinant inbred line (RIL) population with 302 lines derived from a cross of Weimai 8 × Luohan 2 was used to identify the quantitative trait loci (QTL) for plant height (PH) in wheat (Triticum aestivum L.). Possible genetic relationships between PH and PH components (PHC), including spike length (SL) and internode length from the first to the fourth node counted from the top, abbreviated as FIITL, SITL, TITL and FOITL, respectively, were evaluated at the QTL level. A QTL for PH was mapped using data on PH and on PH conditioned by PHC using the IciMapping V3.0 software. Conditional QTL mapping proved that, at the QTL level, SL contributed the least to PH, followed by FIITL and FOITL, while TITL had the strongest influence on PH, followed by SITL. These results indicate that the conditional QTL mapping method can be used to evaluate possible genetic relationships between PH and PHC, and that it can efficiently and precisely reveal counteracting QTL, which will enhance our understanding of the genetic basis of PH in wheat.
Authors:F. Wang, H. Fan, D. Chen, H. Bai, Z. Chen, and L. Xiao
Radiolabeled somatostatin analogue is a useful ligand for scintigraphic imaging of somatostatin receptor-bearing tumors. In
this study, we investigated the effects of different radiolabeling conditions on labeling yield and ratio between mono-iodinated
and di-iodinated125I-Tyr3-octreotide by HPLC analysis. In vitro and in vivo stabilities of125I-Tyr3-octreotide and111In-DTPA-D-Phe1-octreotide were also determined. Both radiolabeled compounds were relatively stable in vitro, but were decomposed to free125I− and111In-DTPA in vivo, respectively.
Authors:H. Bai, H. Jin, H. Fan, J. Du, F. Wang, D. Chen, and Zh. Cheng
The behavior of153Sm-EDTMP in vitro and vivo is analyzed by the size exclusion HPLC. The experimental results show that EDTMP amounts have an
obvious effect on the stability in vitro and uptake of153Sm-EDTMP in the liver. HPLC analysis of urine sample indicates that153Sm-EDTMP es excreted in the original form. The behavior in vivo of153Sm-EDTMP containing 4 μg is similar to that of153Sm-EDTMP containing 50 μg EDTMP at 1 h post-injection.
Authors:Z. Cheng, Q. Lin, X. Jin, F. Wang, H. Bai, D. Chen, H. Fan, and J. Du
DTPA-Octreotide(Pentetreotide), a somatostatin analogue which can bind specifically and with high affinity to somatostatin
receptor in vitro and vivo, labeled with99mTc by tin reduction in acetate buffer, has been characterized by Reverse-phase High performance Liquid Chromatography. The
effect of different solvents, mobile phase pH, linear gradient and the injected volume on the separation efficiency was evaluated.
The results show that the separation efficiency is best using μBondapak-C18 (300×3.9 mm2), linear gradient of 40% to 80% methanol (1.0 ml/min) in 0.05M acetate buffer (pH 5.5) over a 30 min period and maintaining
for another 10 min. The labeled product is a mixture which mainly consists of five components (a, b, c, d, e) successfully
proved by HPLC. Paper chromatography is also evaluated in this paper. It may be used to determine the radiochemical purity
of the labeling product, but is not a good choice for the verification each components.
Authors:H. Bai, X. Jin, F. Wang, J. Du, Y. Liu, and D. Chen
The preparation of a cold kit was introduced in the paper, and the effective quantities of the components (Vc, HEDP and SnCl2·2H2O) in the kit were determined. At the sametime, the effects of labelling kit on the reaction time, reaction temperature and animal distribution were studied in detail. The initial animal experiment showed the high uptake in the skeletal tissue, the clearance in the blood was quick.
Authors:X. P. Geng, H. F. Zhang, B. H. Wang, X. D. Geng, and J. W. Xing
Calorimetric determination of the total enthalpy changes (ΔHi) of guanidine-denatured lysozyme (Lys) during the adsorption with simultaneously refolding on the surface of hydrophobic
interaction chromatography packings was carried out at 250.001C. The measured ΔHiin the circumstances should include the changes in the three fractions: adsorption, dehydration and molecular conformation.
It was found that when the unfolded Lys molecules are adsorbed and refold on the surface, entropy-driving caused by the dehydration
of Lys mainly dominates the foregoing process. The refolding enthalpies of Lys, ΔΔHiwere found to be 10~100 folds higher than that measured in usual solutions.</o:p>