The size of bubbles created in the flotation process is of great importance to the efficiency of the mineral separation achieved.Meanwhile,it is believed that frother transport between phases is perhaps the most impor...The size of bubbles created in the flotation process is of great importance to the efficiency of the mineral separation achieved.Meanwhile,it is believed that frother transport between phases is perhaps the most important reason for the interactive nature of the phenomena occurring in the bulk and froth phases in flotation,as frother adsorbed in the surface of rising bubbles is removed from the bulk phase and then released into the froth as a fraction of the bubbles burst.This causes the increased concentration in the froth compared to the bulk concentration,named as frother partitioning.Partitioning reflects the adsorption of frother on bubbles and how to influence bubble size is not known.There currently exists no such a topic aiming to link these two key parameters.To fill this vacancy,the correspondence between bubble size and frother partitioning was examined.Bubble size was measured by sampling-for-imaging(SFI)technique.Using total organic carbon(TOC)analysis to measure the frother partitioning between froth and bulk phases was determined.Measurements have shown,with no exceptions including four different frothers,higher frother concentration is in the bulk than in the froth.The results also show strong partitioning giving an increase in bubble size which implies there is a compelling relationship between these two,represented by CFroth/CBulk and D32.The CFroth/CBulkand D32 curves show similar exponential decay relationships as a function of added frother in the system,strongly suggesting that the frother concentration gradient between the bulk solution and the bubble interface is the driving force contributing to bubble size reduction.展开更多
【目的】针对杜梨组织中富含多酚、多糖等次生代谢物质特点,筛选从杜梨不同组织中提取高质量RNA的方法。【方法】以杜梨不同组织(根、茎、叶、花和果)为材料,分别采用Trizol法、改良CTAB法和RNAprep Pure Plant Kit试剂盒法提取总RNA,...【目的】针对杜梨组织中富含多酚、多糖等次生代谢物质特点,筛选从杜梨不同组织中提取高质量RNA的方法。【方法】以杜梨不同组织(根、茎、叶、花和果)为材料,分别采用Trizol法、改良CTAB法和RNAprep Pure Plant Kit试剂盒法提取总RNA,利用琼脂糖凝胶电泳和NanoDrop 2000微量分光光度计对RNA进行质量检测。【结果】3种方法均能提出杜梨不同组织中总RNA,但RNAprep Pure Plant Kit法提取的总RNA电泳条带清晰、完整性较好,根、茎、叶、花和果提取的RNA纯度分别为2.07、2.02、2.01、2.01和2.02;浓度分别为186.2 ng·μL^(-1)、174.5 ng·μL^(-1)、163.6 ng·μL^(-1)、167.3 ng·μL^(-1)和121.1 ng·μL^(-1)。以RNAprep Pure Plant Kit试剂盒法提取的总RNA反转录成cDNA为模板,内参基因PbUBI为目的基因进行RT-PCR扩增,均可获得明亮单一条带。【结论】RNAprep Pure Plant Kit试剂盒法更适用于杜梨不同组织总RNA提取,可为下一步进行基因克隆及功能验证等分子生物学研究奠定基础。展开更多
基金Project supported by the Collaborative Research and Development Program of Natural Sciences and Engineering Research Council of Canada
文摘The size of bubbles created in the flotation process is of great importance to the efficiency of the mineral separation achieved.Meanwhile,it is believed that frother transport between phases is perhaps the most important reason for the interactive nature of the phenomena occurring in the bulk and froth phases in flotation,as frother adsorbed in the surface of rising bubbles is removed from the bulk phase and then released into the froth as a fraction of the bubbles burst.This causes the increased concentration in the froth compared to the bulk concentration,named as frother partitioning.Partitioning reflects the adsorption of frother on bubbles and how to influence bubble size is not known.There currently exists no such a topic aiming to link these two key parameters.To fill this vacancy,the correspondence between bubble size and frother partitioning was examined.Bubble size was measured by sampling-for-imaging(SFI)technique.Using total organic carbon(TOC)analysis to measure the frother partitioning between froth and bulk phases was determined.Measurements have shown,with no exceptions including four different frothers,higher frother concentration is in the bulk than in the froth.The results also show strong partitioning giving an increase in bubble size which implies there is a compelling relationship between these two,represented by CFroth/CBulk and D32.The CFroth/CBulkand D32 curves show similar exponential decay relationships as a function of added frother in the system,strongly suggesting that the frother concentration gradient between the bulk solution and the bubble interface is the driving force contributing to bubble size reduction.
文摘【目的】针对杜梨组织中富含多酚、多糖等次生代谢物质特点,筛选从杜梨不同组织中提取高质量RNA的方法。【方法】以杜梨不同组织(根、茎、叶、花和果)为材料,分别采用Trizol法、改良CTAB法和RNAprep Pure Plant Kit试剂盒法提取总RNA,利用琼脂糖凝胶电泳和NanoDrop 2000微量分光光度计对RNA进行质量检测。【结果】3种方法均能提出杜梨不同组织中总RNA,但RNAprep Pure Plant Kit法提取的总RNA电泳条带清晰、完整性较好,根、茎、叶、花和果提取的RNA纯度分别为2.07、2.02、2.01、2.01和2.02;浓度分别为186.2 ng·μL^(-1)、174.5 ng·μL^(-1)、163.6 ng·μL^(-1)、167.3 ng·μL^(-1)和121.1 ng·μL^(-1)。以RNAprep Pure Plant Kit试剂盒法提取的总RNA反转录成cDNA为模板,内参基因PbUBI为目的基因进行RT-PCR扩增,均可获得明亮单一条带。【结论】RNAprep Pure Plant Kit试剂盒法更适用于杜梨不同组织总RNA提取,可为下一步进行基因克隆及功能验证等分子生物学研究奠定基础。
