In recent years much attention has been devoted to AgCl emulsion owing to its se-rial advantages and inimitable potential.But in the research of this emulsion a thorny problem remains unsolved till now,which is the im...In recent years much attention has been devoted to AgCl emulsion owing to its se-rial advantages and inimitable potential.But in the research of this emulsion a thorny problem remains unsolved till now,which is the improvement in sensitivity is always accompanied with high fog density.In this work 5 nm Ag_(2)S particles were prepared and used as novel sensitizers in AgCl cubic and{100}tabular microcrystal emulsions.The novel sensitizer shows an effective sensitizing ability for silver chloride emulsion,and it is superior to the traditional Na_(2)S_(2)O_(3) sensi-tizer because by using it comparatively high sensitivity can be obtained with lower fog density.So the above sensitizing problem is going to be effectively solved.To discover the evolution mechanism of the sensitizer clusters and explain their excellent sensitizing properties,diffuse reflectance spectroscopy(DRS)was used as a probe on the AgCl microcrystal surface.展开更多
本研究旨在比较CTAB法、改良CTAB法、SDS法、氯化苄法和Chelex-100法提取真菌DNA作为PCR模板的效果,以生长速率、菌落形态差异较大的11个煤污病菌属真菌为研究对象,以核糖体RNA(r RNA)基因中的内转录间隔区(ITS)序列和28S r RNA基因部...本研究旨在比较CTAB法、改良CTAB法、SDS法、氯化苄法和Chelex-100法提取真菌DNA作为PCR模板的效果,以生长速率、菌落形态差异较大的11个煤污病菌属真菌为研究对象,以核糖体RNA(r RNA)基因中的内转录间隔区(ITS)序列和28S r RNA基因部分序列的扩增率为指标,采用SPSS软件对结果进行方差分析。结果表明,CTAB法和改良CTAB法适用真菌范围最广,分别有7个和9个属真菌的扩增率都大于70%且无显著性差异;氯化苄法和Chelex-100法适用范围居中,分别有6个和8个属真菌的扩增率较高且无显著性差异,扩增率分别大于70%和50%;SDS法适用范围最窄,有6个属真菌的扩增率高于50%且无显著性差异。大多数煤污病菌至少有2种及以上的DNA提取方法能够取得较好的效果,但链丝孢属真菌只有用氯化苄法提取DNA效果最好。采用改良CTAB法结合氯化苄法,能够满足所有供试煤污病菌类群真菌提取基因组DNA用作PCR反应模板的需要。展开更多
A simple comparative study of synergistic extraction of zinc from ammonium sulfate and ammonium chloride systems with mixtures of Mextral54-100 and tri-nalkylphosphine oxide(TRPO) dissolved in n-heptane was described....A simple comparative study of synergistic extraction of zinc from ammonium sulfate and ammonium chloride systems with mixtures of Mextral54-100 and tri-nalkylphosphine oxide(TRPO) dissolved in n-heptane was described. Various parameters affecting the extraction process were investigated. Experimental results show that extraction from ammonium sulfate is better than that from ammonium chloride under the same conditions owing to the additional complexation between zinc and chloride ions. Total ammonium concentration and pH have a significant effect on zinc extraction efficiency because of the formation of zinc ammine complexes. The synergistic effect is explained by the formation of adduct between zinc chelates and trialkylphosphine oxide. The thermodynamic data show that the extraction reaction is exothermic and stripping is endothermic. Infrared(IR) spectra of the zincloaded organic phases were also examined.展开更多
文摘In recent years much attention has been devoted to AgCl emulsion owing to its se-rial advantages and inimitable potential.But in the research of this emulsion a thorny problem remains unsolved till now,which is the improvement in sensitivity is always accompanied with high fog density.In this work 5 nm Ag_(2)S particles were prepared and used as novel sensitizers in AgCl cubic and{100}tabular microcrystal emulsions.The novel sensitizer shows an effective sensitizing ability for silver chloride emulsion,and it is superior to the traditional Na_(2)S_(2)O_(3) sensi-tizer because by using it comparatively high sensitivity can be obtained with lower fog density.So the above sensitizing problem is going to be effectively solved.To discover the evolution mechanism of the sensitizer clusters and explain their excellent sensitizing properties,diffuse reflectance spectroscopy(DRS)was used as a probe on the AgCl microcrystal surface.
文摘本研究旨在比较CTAB法、改良CTAB法、SDS法、氯化苄法和Chelex-100法提取真菌DNA作为PCR模板的效果,以生长速率、菌落形态差异较大的11个煤污病菌属真菌为研究对象,以核糖体RNA(r RNA)基因中的内转录间隔区(ITS)序列和28S r RNA基因部分序列的扩增率为指标,采用SPSS软件对结果进行方差分析。结果表明,CTAB法和改良CTAB法适用真菌范围最广,分别有7个和9个属真菌的扩增率都大于70%且无显著性差异;氯化苄法和Chelex-100法适用范围居中,分别有6个和8个属真菌的扩增率较高且无显著性差异,扩增率分别大于70%和50%;SDS法适用范围最窄,有6个属真菌的扩增率高于50%且无显著性差异。大多数煤污病菌至少有2种及以上的DNA提取方法能够取得较好的效果,但链丝孢属真菌只有用氯化苄法提取DNA效果最好。采用改良CTAB法结合氯化苄法,能够满足所有供试煤污病菌类群真菌提取基因组DNA用作PCR反应模板的需要。
基金financially supported by the National Basic Research Program of China (No. 2014CB643404)the National Natural Science Foundation of China (Nos.51174104, 51304093, and 51364022)
文摘A simple comparative study of synergistic extraction of zinc from ammonium sulfate and ammonium chloride systems with mixtures of Mextral54-100 and tri-nalkylphosphine oxide(TRPO) dissolved in n-heptane was described. Various parameters affecting the extraction process were investigated. Experimental results show that extraction from ammonium sulfate is better than that from ammonium chloride under the same conditions owing to the additional complexation between zinc and chloride ions. Total ammonium concentration and pH have a significant effect on zinc extraction efficiency because of the formation of zinc ammine complexes. The synergistic effect is explained by the formation of adduct between zinc chelates and trialkylphosphine oxide. The thermodynamic data show that the extraction reaction is exothermic and stripping is endothermic. Infrared(IR) spectra of the zincloaded organic phases were also examined.
