Chalcopyrite is the main Cu-containing mineral and cannot be separated well from pyrite using traditional xanthate collectors with large amounts of lime depressant, resulting in difficulties of the tailing treatment a...Chalcopyrite is the main Cu-containing mineral and cannot be separated well from pyrite using traditional xanthate collectors with large amounts of lime depressant, resulting in difficulties of the tailing treatment and associated precious metals recovery. Therefore, in this study, the green and odourless ethylenediamine tetramethylenephosphonic acid(EDTMPA) was introduced as a novel chalcopyrite collector. Flotation results from the binary mineral mixture and real ore demonstrated that EDTMPA could realize the selective separation of chalcopyrite from pyrite relative to ethyl xanthate(EX) without any depressants within the wide p H range of 6.0–11.0, and might replace the traditional high-alkaline lime process. Electrochemical and Fourier transform infrared spectra measurements indicated that the difference in adsorption performance of EDTMPA on chalcopyrite and pyrite was larger than that of EX, suggesting a better selectivity for EDTMPA. Density functional theory calculations demonstrated that there were stronger chemical bonds between P—O groups of EDTMPA and the Fe/Cu atoms on chalcopyrite in the form of a stable six-membered ring. Crystal chemistry calculations further revealed that the activity of metal atoms of chalcopyrite was higher than that of pyrite. Therefore, these basic theoretical results and practical application provide a guidance for the industrial application of EDTMPA in chalcopyrite flotation.展开更多
In the research, aminoethyl imidazolines of cottonseed oil fatty acids with diethylenetriamine have been synthesized using the ultrasonic device creating the effect of cavitation. The yield of imidazolines was 90% - 9...In the research, aminoethyl imidazolines of cottonseed oil fatty acids with diethylenetriamine have been synthesized using the ultrasonic device creating the effect of cavitation. The yield of imidazolines was 90% - 95%. The influence of the synthesized imidazolines on lubricity quality of low sulfur diesel fuels having low lubricating quality was studied. The results showed that at concentrations 200 - 250 ppm the synthesized imidazolines can be applied as additives enhancing lubricity quality of diesel fuels.展开更多
<span style="font-family:Verdana;">Coordination compounds of 2-amino-3-methylbutanoic acid were synthesized with chromium(III) and oxovanadium(IV) ions. M:L;1:2. Adducts of these complexes using 1,10-p...<span style="font-family:Verdana;">Coordination compounds of 2-amino-3-methylbutanoic acid were synthesized with chromium(III) and oxovanadium(IV) ions. M:L;1:2. Adducts of these complexes using 1,10-phenantroline and ethylenediamine were further synthesized, M:L, (1:2). These compounds were characterized using electronic, infra-red spectrophotometry, magnetic susceptibility measurement and percentage metal analyses. The zones of inhibition and minimum inhibitory concentrations of the compounds against eight microbes were studied. The results obtained indicated an octahedral geometry for the Cr(III) complexes, indicative of additional coordination of two water molecules. On the other hand a square pyramid geometry was obtained for the binary oxovanadium complex and its 1,10-phenantroline adduct. However</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> for the oxovanadium ethylenediamine adduct a distorted octahedral geometry was proposed. The result for the antibacterial studies indicated that both mixed ligand complexes of 1,10-phenantroline exhibited good antibacterial activity, and in some cases better activity than the standard, streptomycin.</span></span></span>展开更多
A new separation system of capillary electrophoresis for the simultaneous determination of metals by using ethylenediamine tetraacetic acid （EDTA） as complexing agent and employing vancomycin as complex selector was...A new separation system of capillary electrophoresis for the simultaneous determination of metals by using ethylenediamine tetraacetic acid （EDTA） as complexing agent and employing vancomycin as complex selector was described. The Z-shape cell capillary electrophoresis was used to enhance the sensitivity for the determination of the complexes of Cu（Ⅱ）, Ni（Ⅱ）, Co（Ⅱ） and Fe（Ⅲ） with EDTA. The partial filling method （co-current mode） was used in order to increase the selectivity of the electrophoretic method, meanwhile vancomycin was not present at the detector path during the detection of metal-EDTA complexes. The vancomycin concentration, phosphate concentration and pH of the buffer strongly influenced mobility, resolution and selectivity of the studied analytes. Under the optimal condition, the relative standard deviations （n=5） of the migration time and the peak area were less than 3.14% and 7.35%, respectively. Application of the Z-shape cell capillary electrophoresis method with UV detection and vancomycin loading led to the reliable determination of these metal ions in tap water and the recoveries were 97%-101%. The detection limits based on a signal to noise ratio of 3 ： 1 were found in the range of 2-10 μg·L^-1.展开更多
以乙二胺为主剂，硼酸、磷酸、柠檬酸和硫酸为添加剂，配制乙二胺类烟气吸收剂，测定其对SO2吸收容量和脱除效率的影响。结果显示，乙二胺／硼酸对SO2吸收容量为450mg／L，脱硫率达97％；同时研究乙二胺／硼酸溶液10次吸收一解吸循环过...以乙二胺为主剂，硼酸、磷酸、柠檬酸和硫酸为添加剂，配制乙二胺类烟气吸收剂，测定其对SO2吸收容量和脱除效率的影响。结果显示，乙二胺／硼酸对SO2吸收容量为450mg／L，脱硫率达97％；同时研究乙二胺／硼酸溶液10次吸收一解吸循环过程。数据表明，SO2的脱除效率达99％，解吸后pH稳定在6．10-23；选择乙二胺／硼酸为最佳脱硫剂，在鼓泡反应器中对湿法烟气脱硫（wetflue gas desulphurization，WFGD）工艺进行研究。通过改变吸收剂温度、乙二胺浓度、吸收剂pH和SO2进口浓度，探讨其对脱硫率的影响。确定吸收SO2适宜的工艺条件：吸收剂温度30℃，乙二胺浓度0．3mol／L，吸收剂pH为8．5。结果显示，实验范围内，烟气中SO2浓度越大，脱硫率越高。展开更多
目的 : 研究在中国典型膳食条件下乙二胺四乙酸铁钠 ( Na Fe EDTA)中铁在人体的吸收率。方法 : 采用铁稳定性同位素54 Fe和58Fe分别标记 Fe SO4 和 Na Fe EDTA并以稀土元素镝 ( Dy)作为排泄物回收标记物。自愿受试者为 1 8～ 2 2岁健...目的 : 研究在中国典型膳食条件下乙二胺四乙酸铁钠 ( Na Fe EDTA)中铁在人体的吸收率。方法 : 采用铁稳定性同位素54 Fe和58Fe分别标记 Fe SO4 和 Na Fe EDTA并以稀土元素镝 ( Dy)作为排泄物回收标记物。自愿受试者为 1 8～ 2 2岁健康女性。采用我国典型城镇成年女性膳食模式。两种铁剂和 Dy以酱油为食物载体一同分两天 6次经口给入。实验期间每日留取受试者膳食样品并收集受试者在实验期的粪便。采用原子吸收 ( AAS)和等离子体质谱 ( ICP- MS)分别检测膳食和粪便中总铁含量和铁同位素比例 ,对两种铁剂中铁的吸收率进行比较。结果 : Fe SO4 的铁平均吸收率为 4.73% ,而 Na Fe EDTA为 1 0 .51 % ,两者差异为极显著 ( P<0 .0 1 )。结论 : Na Fe EDTA中铁的吸收率优于 Fe SO4 。展开更多
基金financial supports from the Key Program for International S&T Cooperation Projects of China (No. 2021YFE0106800)the National Natural Science Foundation of China (No. U2067201)+3 种基金the Leading Talents of S & T Innovation of Hunan Province, China (No. 2021RC4002)the Science Fund for Distinguished Young Scholars of Hunan Province, China (No. 2020JJ2044)the Key Research and Development Program of Hunan Province, China (No. 2021SK2043)the National 111 Project, China (No. B14034)。
文摘Chalcopyrite is the main Cu-containing mineral and cannot be separated well from pyrite using traditional xanthate collectors with large amounts of lime depressant, resulting in difficulties of the tailing treatment and associated precious metals recovery. Therefore, in this study, the green and odourless ethylenediamine tetramethylenephosphonic acid(EDTMPA) was introduced as a novel chalcopyrite collector. Flotation results from the binary mineral mixture and real ore demonstrated that EDTMPA could realize the selective separation of chalcopyrite from pyrite relative to ethyl xanthate(EX) without any depressants within the wide p H range of 6.0–11.0, and might replace the traditional high-alkaline lime process. Electrochemical and Fourier transform infrared spectra measurements indicated that the difference in adsorption performance of EDTMPA on chalcopyrite and pyrite was larger than that of EX, suggesting a better selectivity for EDTMPA. Density functional theory calculations demonstrated that there were stronger chemical bonds between P—O groups of EDTMPA and the Fe/Cu atoms on chalcopyrite in the form of a stable six-membered ring. Crystal chemistry calculations further revealed that the activity of metal atoms of chalcopyrite was higher than that of pyrite. Therefore, these basic theoretical results and practical application provide a guidance for the industrial application of EDTMPA in chalcopyrite flotation.
文摘In the research, aminoethyl imidazolines of cottonseed oil fatty acids with diethylenetriamine have been synthesized using the ultrasonic device creating the effect of cavitation. The yield of imidazolines was 90% - 95%. The influence of the synthesized imidazolines on lubricity quality of low sulfur diesel fuels having low lubricating quality was studied. The results showed that at concentrations 200 - 250 ppm the synthesized imidazolines can be applied as additives enhancing lubricity quality of diesel fuels.
文摘<span style="font-family:Verdana;">Coordination compounds of 2-amino-3-methylbutanoic acid were synthesized with chromium(III) and oxovanadium(IV) ions. M:L;1:2. Adducts of these complexes using 1,10-phenantroline and ethylenediamine were further synthesized, M:L, (1:2). These compounds were characterized using electronic, infra-red spectrophotometry, magnetic susceptibility measurement and percentage metal analyses. The zones of inhibition and minimum inhibitory concentrations of the compounds against eight microbes were studied. The results obtained indicated an octahedral geometry for the Cr(III) complexes, indicative of additional coordination of two water molecules. On the other hand a square pyramid geometry was obtained for the binary oxovanadium complex and its 1,10-phenantroline adduct. However</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> for the oxovanadium ethylenediamine adduct a distorted octahedral geometry was proposed. The result for the antibacterial studies indicated that both mixed ligand complexes of 1,10-phenantroline exhibited good antibacterial activity, and in some cases better activity than the standard, streptomycin.</span></span></span>
基金Project supported by the National Natural Science Foundation of China （Nos. 20437020 and 20575008） and the Post Doctoral Research Scholarship of Department of Chemistry, Tsinghua University.
文摘A new separation system of capillary electrophoresis for the simultaneous determination of metals by using ethylenediamine tetraacetic acid （EDTA） as complexing agent and employing vancomycin as complex selector was described. The Z-shape cell capillary electrophoresis was used to enhance the sensitivity for the determination of the complexes of Cu（Ⅱ）, Ni（Ⅱ）, Co（Ⅱ） and Fe（Ⅲ） with EDTA. The partial filling method （co-current mode） was used in order to increase the selectivity of the electrophoretic method, meanwhile vancomycin was not present at the detector path during the detection of metal-EDTA complexes. The vancomycin concentration, phosphate concentration and pH of the buffer strongly influenced mobility, resolution and selectivity of the studied analytes. Under the optimal condition, the relative standard deviations （n=5） of the migration time and the peak area were less than 3.14% and 7.35%, respectively. Application of the Z-shape cell capillary electrophoresis method with UV detection and vancomycin loading led to the reliable determination of these metal ions in tap water and the recoveries were 97%-101%. The detection limits based on a signal to noise ratio of 3 ： 1 were found in the range of 2-10 μg·L^-1.
文摘以乙二胺为主剂，硼酸、磷酸、柠檬酸和硫酸为添加剂，配制乙二胺类烟气吸收剂，测定其对SO2吸收容量和脱除效率的影响。结果显示，乙二胺／硼酸对SO2吸收容量为450mg／L，脱硫率达97％；同时研究乙二胺／硼酸溶液10次吸收一解吸循环过程。数据表明，SO2的脱除效率达99％，解吸后pH稳定在6．10-23；选择乙二胺／硼酸为最佳脱硫剂，在鼓泡反应器中对湿法烟气脱硫（wetflue gas desulphurization，WFGD）工艺进行研究。通过改变吸收剂温度、乙二胺浓度、吸收剂pH和SO2进口浓度，探讨其对脱硫率的影响。确定吸收SO2适宜的工艺条件：吸收剂温度30℃，乙二胺浓度0．3mol／L，吸收剂pH为8．5。结果显示，实验范围内，烟气中SO2浓度越大，脱硫率越高。
基金supported by the Science&Technology Pillar Program of Jiangxi,China(2009BSB08600)Scientific Research Fund from the Education Bureau of Jiangxi,China(GJJ10494)~~
