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Phase behavior of the extraction system, Cyanex 923–heptane/H2SO4–H2O has been studied. The third phase appeared at different aqueous H2SO4 concentration with varying initial Cyanex 923 concentration and temperature affects its appearance. Almost all of H2SO4 and H2O are extracted into the middle phase. The H2SO4 concentration in the third phase increases with the increasing aqueous acid concentration (CH2SO4,b) while the water content first increases and then reaches a constant value at CH2SO4,b=11.3 mol l−1. In the region of CH2SO4,b higher than 5.2 mol l−1, the composition of the middle phase is only related to the equilibrium concentration of H2SO4 in the bottom phase. H2SO4 and H2O are transferred into the middle phase mainly by their coordination with Cyanex 923 when CH2SO4,b is less than 11.3 mol l−1. When CH2SO4,b is higher than 11.3 mol l−1, excess H2SO4 is solubilized into the polar layer of the aggregates. In the region considered, the extracted complex changes from C923 · H2SO4 to C923 · H2SO4 · H2O and then to C923 · (H2SO4)2 · H2O. [Copyright &y& Elsevier]

Neosartoryadins A (1) and B (2), both with a unique 6/6/6/5 quinazoline ring system connected directly to a 6/5/5 imidazoindolone ring, together with three biogenetically related compounds 3-5, were isolated from the endophytic fungus Neosartorya udagawae HDN13-313. The absolute configurations of new compounds 1-4 were established. Compounds 1 and 2 displayed anti-influenza virus A (H1N1) activities with IC50 values of 66 and 58 μM, respectively (ribavirin as positive control, IC50 = 94 μM).

Wheat head blight caused mainly by Fusarium graminearum, is an important wheat disease, causing yield and quality losses. The breeding of resistant varieties is the key measure to control this disease, but the conventional breeding method is of low efficiency. The marker-assisted selection (MAS) can significantly improve the breeding efficiency. In this study, four RAPD (randomly amplified polymorphic DNA) markers linked to FHB resistance were obtained and one was cloned and sequenced. F7 recombinant inbred lines (RILs) were derived from the F1 of the cross Ning894037 (resistant)/Alondra (susceptible) by the single-seed descent method. Scab resistance of F7 RILs was evaluated in the greenhouse by injecting conidiospores into a central floret. Scab symptoms were evaluated on the 21st day after inoculation. Disease severity was assessed as the percentage of infected spikelets/spike. The F7 RIL population displayed a normal distribution, transgressive segregation and significant variation for FHB severity. DNA from resistant and susceptible parents was analyzed with 520 RAPD primers. Four markers (S1384-640,S1360-600, S1319-350,S1319-820) linked to FHB resistance were obtained. DNA of S1384-640 was recovered, subjected to re-amplification by using S1384 primer and the same protocol as for RAPD analysis and identified the rightness. The PCR product of S1384-640 was ligated into the pUCm-T vector, and cloned into fresh competent cells of Escherichia coli strain DH5alpha RAPD analysis showed that the inserts of the recombinant plasmids were DNA of S1384-640. The sequencing result showed that the cloned fragment was 648 bp.

Phase behavior of the extraction system, Cyanex 923-heptane/H(2)SO(4)-H(2)O has been studied. The third phase appeared at different aqueous H(2)SO(4) concentration with varying initial Cyanex 923 concentration and temperature affects its appearance. Almost all of H(2)SO(4) and H(2)O are extracted into the middle phase. The H(2)SO(4) concentration in the third phase increases with the increasing aqueous acid concentration (C(H(2)SO(4),b)) while the water content first increases and then reaches a constant value at C(H(2)SO(4),b)=11.3 mol l(-1). In the region of C(H(2)SO(4),b) higher than 5.2 mol l(-1), the composition of the middle phase is only related to the equilibrium concentration of H(2)SO(4) in the bottom phase. H(2)SO(4) and H(2)O are transferred into the middle phase mainly by their coordination with Cyanex 923 when C(H(2)SO(4),b) is less than 11.3 mol l(-1). When C(H(2)SO(4),b) is higher than 11.3 mol l(-1), excess H(2)SO(4) is solubilized into the polar layer of the aggregates. In the region considered, the extracted complex changes from C923 . H(2)SO(4) to C923 . H(2)SO(4) . H(2)O and then to C923 . (H(2)SO(4))(2) . H(2)O.

Studies of the extraction kinetics of cerium(IV) from H(2)SO(4)-HF solutions with Cyanex 923 in n-heptane have been carried out using a constant interfacial area cell with laminar flow. The experimental hydrodynamic conditions were chosen so that the contribution of diffusion to the measured rate of reaction was minimized. The data were analyzed in terms of pseudo-first order constants. The results were compared with those of the system without HF. It was concluded that the addition of HF reduces the activation energy for the forward rate from 46.2 to 36.5 kJ mol(-1) while it has an opposite effect on the activation energy for the reverse process(the activation energy increased from 23.3 to 90.8 kJ mol(-1)). Thus, HF can accelerate the rate of cerium(IV) extraction. At the same time, the extraction rate is controlled by a mixed chemical reaction-diffusion rather than by a chemical reaction alone. A rate equation has also been obtained.