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  • Author or Editor: S. Qiu x
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Abstract  

The sensitivity in the determination of deuterium and15N by nuclear reactions was examined for the following reactions: (1)15N(d,n)16O (or p+)+(6.13, 7.11 MeV); (2) D(3He,)4He (13 MeV); and (3)15N(,n)18F. By these activations with suitable etching techniques, sub ppm regions of D and15N have proved to be measurable with their depth profiles. Some fundamental properties of hydrogen and nitrogen in silicon are under investigation using of these activable tracers.

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Abstract  

The principle for the electro-generative simultaneous leaching (EGSL) is applied to simultaneous leaching of pyrite-MnO2 in this paper. A galvanic system for the bio-electro-generative simultaneous leaching (BEGSL) has been set up. The equation of electric quantity vs. time is used to study the effect of produced sulfur on electro-generative efficiency and quantity. It has been shown that the resistance decreased in the presence of Acidithiobacillus thiooxidans (A. thiooxidans) with the increase of electro-generative efficiency. The effects of temperature and grain size on rate of ferrous extraction from pyrite under the conditions of presence and absence of A. thiooxidans were studied, respectively. The changes in the extraction rate of Fe2+ as particle size in presence of A. thiooxidans were more evident than that in the absence, which indicated that the extraction in bio-electro-generative leaching was affected by particle size remarkably. Around the optimum culture temperature for A. thiooxidans, the bigger change in the conversion rate of Fe2+ was depending on temperature. The transferred charge in BEGSL including part of S0 to sulfate group in the presence of (A. thiooxidans) which is called as biologic electric quantity, and the ratio of biologic electric quantity reached to 58.10% in 72 h among the all-transferred charge.

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Abstract  

The effects of Amoxicillin Sodium and Cefuroxime Sodium on the growth of E. coli DH5α were investigated by microcalorimetry. The metabolic power-time curves of E. coli DH5α growth were determined by using a TAM air isothermal microcalorimeter at 37�C. By evaluation of the obtained parameters, such as growth rate constants (k), inhibitory ratio (I), the maximum heat power (P m) and the time of the maximum heat power (t m), one found that the inhibitory activity of Amoxicillin Sodium vs. E. coli DH5α is enhanced with the increasing of the Amoxicillin Sodium concentration, and the Cefuroxime Sodium has a stimulatory effect on the E. coli DH5α growth when the concentration is about 1 μg mL−1. The IC50 for the Amoxicillin Sodium and the Cefuroxime Sodium are 1.6 and 2.0 μg mL−1, respectively, it implicates that the E. coli DH5α is more sensitive to Amoxicillin Sodium than Cefuroxime Sodium.

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Abstract  

The low-temperature molar heat capacities of CoPc and CoTMPP were measured by temperature modulated differential scanning calorimetry (TMDSC) over the temperature range from 223 to 413 K for the first time. No phase transition or thermal anomaly was observed in the experimental temperature range for CoPc. However, a structural change was found to be nonreversible for CoTMPP in the temperature range of 368–403 K, which was further validated by the results of IR and XRD. The molar enthalpy ΔH m and entropy ΔS m of phase transition of the CoTMPP were determined to be 3.301 kJ mol−1 and 8.596 J K−1 mol−1, respectively. The thermodynamic parameters of CoPc and CoTMPP such as entropy and enthalpy relative to reference temperature 298.15 K were derived based on the above molar heat capacity data. Moreover, the thermal stability of these two compounds was further investigated through TG measurements. Three steps of mass loss were observed in the TG curve for CoPc and five steps for CoTMPP.

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Abstract  

A dual cell system was used to study the electrogenerative leaching sphalerite-MnO2 under the conditions of presence and absence of Acidithiobacillus ferrooxidans (A. ferrooxidans). The polarization of anode and cathode, and the relationship between the electric quantity (Q) and some factors, such as the dissolved Zn2+, Fe2+, the time in the bio-electro-generating simultaneous leaching (BEGSL) and electro-generating simultaneous leaching (EGSL), were studied. The results show that the dissolved Zn2+ in the presence of A. ferrooxidans is nearly 60% higher than that in the absence of A. ferrooxidans; the electrogenerative quantity in the former is about 134% more than that in the latter. A three-electrode system was applied to study anodic and cathodic self-corrosion current, which was inappreciable compared with the galvanic current between sphalerite and MnO2. The accumulated sulfur on the surface of sulfides produced in the electrogenerative leaching process could be oxidized in the presence of A. ferrooxidans, and the ratio of biological electric quantity reached to 31.72% in 72 h.

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The powdery mildew resistance gene Pm2 is effective in China. Bulked segregant analysis (BSA) was used to search for microsatellite markers linked to Pm2 . Twenty-one microsatellite primer pairs located on chromosome 5DS were screened; three polymorphic loci Xcfd81 -5DS, Xgwm190 -5DS, and Xcfd18 -5DS were linked to Pm2 using an F 2 population from Chinese Spring × C114118 (with Pm2 ) consisting of 814 individuals. The genetic distances between Pm2 and the three markers were: 2.0cM, 34.2cM and 44.2cM, respectively. Microsatellite marker Xcfd81 -5DS could be used in marker assisted selection for Pm2 provided any chosen Pm2 source also carries the relevant marker.

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