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We investigate the global existence and the boundedness of solutions of a second order nonlinear differential system.

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Fusarium head blight disease (FHB) in wheat, caused by Fusarium graminearum species complex (Fg complex), is a very serious disease threatening wheat production worldwide. Polymerase chain reaction (PCR) based methods have been established for rapid and quantitative detection of many plant pathogens. In this study, a specific pair of primers was designed based on the sequence of DNA fragment (740 bp) amplified by a microsatellite primer M13 from Fg complex isolates. This pair of primers was able to amplify a 380 bp fragment from all Fg complex isolates but not from any other tested fungal species. Using this pair of primers, a real-time PCR assay was developed to quantitatively detect small amounts of Fg complex in wheat seeds. This sensitive and quantitative detection assay could be useful in epidemiological studies and assessment of mycotoxin contamination in wheat seeds.

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Summary

The ripe fruits of Schisandrae chinensis have a long history of use in traditional Chinese medicine to treat diseases and improve health. There is substantial evidence that lignan constituents are mainly responsible for the beneficial effects of this plant medicine. The amounts of the major bioactive lignans in this plant vary widely with species, habitat, and the collecting time, and as such, establishment of an HPLC fingerprint for quality control of this herbal medicine is of particular importance. To achieve this, ten batches of Fructus schisandrae chinensis were collected from Tieli, in China, and their chemical components were analyzed under optimized HPLC conditions. On the basis of the chromatographic data, a consistent HPLC fingerprint pattern containing 20 common peaks was obtained. Among these common peaks, six were identified as schizandrin, schizandrol B, schisantherin, deoxyschiandrin, γ-schizandrin B, and schizandrin C. On the basis of this HPLC fingerprint and principal-components analysis, the quality of fifteen samples from different producing areas of China was objectively assessed, and the species difference between Fructus schisandrae sphenantherae and Fructus schisandrae chinensis was clearly differentiated. To summarize, the data described in this study offer valuable information for quality control and proper use of Fructus schisandrae chinensis.

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Abstract  

The thermal decomposition characteristics of1,7-diazido-2,4,6-trinitrazaheptane (DATH) and multi-component systems containing DATH were studied by using DSC, TG and DTG techniques. Three –NO2 groups in the DATH molecule break away first from the main chain when DATH is heated up to 200C. Following this process, the azido groups and the residual molecule decompose rapidly to release a great deal of heat within a short time. In the multi-component systems, DATH undergoes a strong interaction with the binder of the double-base propellant and a weak interaction with RDX. The burning rates of the two propellants were determined by using a Crawford bomb. The results showed that the burning rate rises by about 19–66% when 23.5%DATH is substituted for RDX in a minimum smoke propellant. Meanwhile, the N2 level in the combustion gases is enhanced, which is valuable for a reduction of the signal level of the solid propellant.

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The desorption behaviour (desorption temperature and extent of desorption) of HF,HCFC-133a (CF3CH2Cl) and HFC-134a (CF3CH2F) on γ-AlF3 or catalyst supported on γ-AlF3 was studied using an adsorption apparatus and TG, DTA and DSC methods. On the basis of the results a reaction mechanism was proposed for the preparation of HFC-134a. The γ-AlF3 employed for preparing the catalyst was expected to be stable below 550C based on the crystalline phase transition temperature of γ-AlF3.

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Journal of Thermal Analysis and Calorimetry
Authors: Z. Xiao, D. Liu, C. Wang, Z. Cao, X. Zhan, Z. Yin, Q. Chen, H. Liu, F. Xu, and L. Sun

Abstract  

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.

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Abstract  

A radioactive multitracer solution was prepared from the reaction of selenium with 25 MeV/nucleon40Ar ions. Using off-line -ray spectrometry, the solution containing 47 radioactive isotopes of 24 elements was obtained. The nucleide with the longest half-life was22Na, and the shortest-lived one was81Rb8.

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Traditional Chinese medicine (TCM) has been widely used in many countries for thousands of years and played an indispensable role in the prevention and treatment of diseases, especially the complicated and chronic ones. However, the application of TCM in diseases is still not fully recognized by people around the world, the main reason is that Chinese herb is a very complex mixture containing hundreds of different components. Thus, it is essential to make quality control and evaluation of TCM. A new quality evaluation method, quantitative analysis of multi-components by single marker (QAMS), was developed to the quality control of alkaloids in TCM, a case study on Radix aconiti lateralis, named Fuzi in Chinese. Six alkaloids, including aconitine, hypaconitine, mesaconitine, benzoylaconine, benzoylmesaconine, and benzoylhypaconine, were selected as main components to evaluate the quality of Radix aconiti lateralis. The feasibility and accuracy of QAMS were checked by the external standard method, and various high-performance liquid chromatographic instruments and chromatographic conditions were investigated to verify its applicability. Using aconitine as the internal reference substance and the content of aconitine was calculated according to relative correction factors by high-performance liquid chromatography. The present results showed that there was no significant difference observed between the QAMS method and the external standard method with the relative average deviations less than 3.0%, and QAMS is an effective way to control the quality of herbal medicines and seems to be a convenient and accurate approach to analyze multi-composition when reference substances are unavailable.

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