Foam stability tests were performed using sodium dodecyl sulfate(SDS)surfactant and SiO2 nanoparticles as foaming system at different asphaltene concentrations,and the half-life of CO_(2) foam was measured.The mechani...Foam stability tests were performed using sodium dodecyl sulfate(SDS)surfactant and SiO2 nanoparticles as foaming system at different asphaltene concentrations,and the half-life of CO_(2) foam was measured.The mechanism of foam stability reduction in the presence of asphaltene was analyzed by scanning electron microscope(SEM),UV adsorption spectrophotometric concentration measurement and Zeta potential measurement.When the mass ratio of synthetic oil to foam-formation suspension was 1:9 and the asphaltene mass fraction increased from 0 to 15%,the half-life of SDS-stabilized foams decreased from 751 s to 239 s,and the half-life of SDS/silica-stabilized foams decreased from 912 s to 298 s.When the mass ratio of synthetic oil to foam-formation suspension was 2:8 and the asphaltene mass fraction increased from 0 to 15%,the half-life of SDS-stabilized foams decreased from 526 s to 171 s,and the half-life of SDS/silica-stabilized foams decreased from 660 s to 205 s.In addition,due to asphaltene-SDS/silica interaction in the aqueous phase,the absolute value of Zeta potential decreases,and the surface charges of particles reduce,leading to the reduction of repulsive forces between two interfaces of thin liquid film,which in turn,damages the foam stability.展开更多
Ameliorating the problem of low leaching efficiency,long leaching period,and high agent consumption should be studied to efficiently exploit ion-absorbed rare earth ore resources.In this study,the surfactant sodium do...Ameliorating the problem of low leaching efficiency,long leaching period,and high agent consumption should be studied to efficiently exploit ion-absorbed rare earth ore resources.In this study,the surfactant sodium dodecyl sulfate(SDS) is used to enhance the leaching effect of an ion-absorbed rare earth ore by ameliorating the seepage effect for the first time.The effects of surfactant concentration,leaching agent dosage,solution flow velocity,and solution pH on the leaching rate were explored,and the mechanism of SDS was discussed.Under the optimum conditions,the addition of a small amount of SDS(mass fraction0.04%) can increase the leaching rate by about 5%,shorten the leaching period,and reduce the consumption of the leaching agent.SDS significantly ameliorates the seepage effect of the ore body by reducing the surface tension of the leaching agent and ameliorating the wettability of the mineral surface.This effect is the main factor that improves the leaching efficiency.DFT(density functional theory) calculation results show that SDS can react with rare earth ions,which reduces the adsorption strength on clay mineral surfaces.Hence,rare earth ions are easily exchanged by ammonium ions,and mass transfer is enhanced.展开更多
A sensitive and simple solid phase extraction method for the simultaneous determination of trace and toxic metals in environmental samples has been reported. The method is based on the adsorption of Zinc, Iron and Cop...A sensitive and simple solid phase extraction method for the simultaneous determination of trace and toxic metals in environmental samples has been reported. The method is based on the adsorption of Zinc, Iron and Copper on SDS-coated alumina nanoparticles, which is also modified with 3-mercapto-D-valine. The retained analyte ions on modified solid phase were eluted using 5 mL of 4 mol·L﹣1 HNO3. The analyte determination was carried out by flame atomic absorption spectrometry. The influences of some metal ion and anions on the recoveries of understudy analyte ion were investigated. The influences of the analytical parameters including pH, ligand and SDS amount, eluting solution (type and concentrations) and sample volume on metal ions recoveries were investigated. The extraction efficiency was > 98% with relative standard deviation lower than 3% the method has been successfully applied for the extraction and determination of these ions content in some real samples. Prepared adsorbent was characterized by SEM and FT-IR measurements.展开更多
This study is to prepare chitosan beads modified with sodium dodecyl sulfate (SDS) to effectively remove Cr(III) from an aqueous solution. The characterizations of SDS-chitosan by scanning electron microscopy-energy d...This study is to prepare chitosan beads modified with sodium dodecyl sulfate (SDS) to effectively remove Cr(III) from an aqueous solution. The characterizations of SDS-chitosan by scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), Fourier transform-infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) proved the successful synthesis of the adsorbent. The adsorption of Cr(III) on the SDS material was investigated by varying experimental conditions such as pH, contact time and adsorbent dosage. The maximum adsorption capacity of SDS-chitosan for Cr(III) was estimated to be 3.42 mg?g<sup>-1</sup>. The results of adsorption kinetics and isothermal models show that the adsorption process conforms to the pseudo-second-order and Langmuir isotherm models, indicating that the adsorption is single-layer chemical adsorption. Thermodynamic analyses indicate that the adsorption of Cr(III) is an endothermic reaction. These results show that the new adsorbent has obvious application prospect to eliminate Cr(III).展开更多
Molecular dynamics simulations have been performed on the fully hydrated lipid bilayer with different concentrations of sodium dodecyl sulfate （SDS）. SDS can readily penetrate into the membrane. The insertion of SDS...Molecular dynamics simulations have been performed on the fully hydrated lipid bilayer with different concentrations of sodium dodecyl sulfate （SDS）. SDS can readily penetrate into the membrane. The insertion of SDS causes a decrease in the bilayer area and increases in the bilayer thickness and lipid tail order, when the fraction of SDS is less than 28%. Through calculating the binding energy, we confirm that the presence of SDS strengthens the interactions among the DPPC lipids, while SDS molecules act as intermedia. Both the strong hydrophilic interactions between sulfate and phosphocholine groups and the hydrophobic interactions between SDS and DPPC hydrocarbon chains contribute to the tight packing and ordered alignment of the lipids. These results are in good agreement with the experimental observations and provide atomic level information that complements the experiments.展开更多
The electrooxidation of tetracycline (TC) at acetylene black electrode has been studied in the presence of sodium dodecyl sulfate (SDS). Tetracycline (TC) exhibited very sensitive oxidation peak in this system. The pe...The electrooxidation of tetracycline (TC) at acetylene black electrode has been studied in the presence of sodium dodecyl sulfate (SDS). Tetracycline (TC) exhibited very sensitive oxidation peak in this system. The peak current was proportional to TC concentration, and the detection limit was 1.2×10-8 mol/L. The system was used to the determination of TC in Pharmaceuticals.展开更多
Dynamics of a single cavitation bubble in sodium dodecyl sulfate（SDS） aqueous solutions is investigated experimentally and theoretically. The bubble pulsation is measured by a phase-locked integrated imaging techniq...Dynamics of a single cavitation bubble in sodium dodecyl sulfate（SDS） aqueous solutions is investigated experimentally and theoretically. The bubble pulsation is measured by a phase-locked integrated imaging technique,and the ambient radius is obtained by fitting the numerical calculation based on the Rayleigh–Plesset bubble dynamics model to the experimental data. The results show that, under the same driving condition, the ambient radius of the cavitation bubble decreases correspondingly with the increase of SDS concentration within the critical micelle concentration, while the compression ratio of the radius increases, which indicates that the addition of SDS decreases the internal molecular number of the cavitation bubble and increases the power capability of the cavitation bubble. In addition, bubble oscillation increases the concentration of the surfactant molecules on the bubble wall, so that the effect of SDS on a single cavitation bubble is reduced when the SDS concentration is greater than 0.8 m M.展开更多
目的:建立快速、简便测定鲜牛奶、转基因牛奶和人乳中乳铁蛋白的方法。方法:在对样品脱脂和去除酪蛋白时,水洗乳脂、酪蛋白以提高乳铁蛋白的回收率。通过十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(sodiumdodecyl sulfate-polyacrylamide gel e...目的:建立快速、简便测定鲜牛奶、转基因牛奶和人乳中乳铁蛋白的方法。方法:在对样品脱脂和去除酪蛋白时,水洗乳脂、酪蛋白以提高乳铁蛋白的回收率。通过十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(sodiumdodecyl sulfate-polyacrylamide gel electrophoresis,SDS-PAGE)分离乳清蛋白,薄层扫描法定量。对电泳和薄层扫描的条件进行优化,电泳使用1.0mm×10齿的试样格、分离胶质量浓度12g/mL、分离电压100V、上样量5μL、染色3h、脱色2h;薄层扫描采取锯齿、双波长、透射的扫描方式,Y步长和摆幅宽分别为0.1mm和8mm。结果:可以分离不同来源乳中的乳铁蛋白、α-乳白蛋白和β-乳球蛋白;乳铁蛋白加标回收率分别为104.53%、108.37%,同板精密度RSD值为3.1003%和1.8151%,在100～2000μg/mL范围内呈线性关系,相关系数为0.9988和0.9990。结论:此方法可以用于3种乳中乳铁蛋白的测定。展开更多
甲烷水合物蓄冷量的确定是甲烷水合物蓄冷降温技术实现工业化的关键.为探究SDS对甲烷水合物蓄冷量的影响,根据Clausius-Clapeyron方程及三参数对应态原理,建立甲烷水合物蓄冷量的计算模型.利用可视化水合物蓄冷实验系统,结合定温压力搜...甲烷水合物蓄冷量的确定是甲烷水合物蓄冷降温技术实现工业化的关键.为探究SDS对甲烷水合物蓄冷量的影响,根据Clausius-Clapeyron方程及三参数对应态原理,建立甲烷水合物蓄冷量的计算模型.利用可视化水合物蓄冷实验系统,结合定温压力搜索法测定四组不同SDS浓度体系下甲烷水合物的相平衡条件.依据实验数据和该模型计算得到不同体系、不同相平衡参数下甲烷水合物的蓄冷量.结果表明：甲烷水合物具有较高的蓄冷密度,蓄冷量达40～ 60 k J/mol;甲烷水合物的蓄冷量不但与相平衡条件有关,还与SDS的添加浓度有关.相平衡温度越高、SDS添加浓度越高,甲烷气体生成水合物时蓄冷量越低.该研究为甲烷水合物蓄冷降温系统的研制提供了参考.展开更多
文摘Foam stability tests were performed using sodium dodecyl sulfate(SDS)surfactant and SiO2 nanoparticles as foaming system at different asphaltene concentrations,and the half-life of CO_(2) foam was measured.The mechanism of foam stability reduction in the presence of asphaltene was analyzed by scanning electron microscope(SEM),UV adsorption spectrophotometric concentration measurement and Zeta potential measurement.When the mass ratio of synthetic oil to foam-formation suspension was 1:9 and the asphaltene mass fraction increased from 0 to 15%,the half-life of SDS-stabilized foams decreased from 751 s to 239 s,and the half-life of SDS/silica-stabilized foams decreased from 912 s to 298 s.When the mass ratio of synthetic oil to foam-formation suspension was 2:8 and the asphaltene mass fraction increased from 0 to 15%,the half-life of SDS-stabilized foams decreased from 526 s to 171 s,and the half-life of SDS/silica-stabilized foams decreased from 660 s to 205 s.In addition,due to asphaltene-SDS/silica interaction in the aqueous phase,the absolute value of Zeta potential decreases,and the surface charges of particles reduce,leading to the reduction of repulsive forces between two interfaces of thin liquid film,which in turn,damages the foam stability.
基金supported by the National Natural Science Foundation of China (Nos. 51774153 and 92062110)。
文摘Ameliorating the problem of low leaching efficiency,long leaching period,and high agent consumption should be studied to efficiently exploit ion-absorbed rare earth ore resources.In this study,the surfactant sodium dodecyl sulfate(SDS) is used to enhance the leaching effect of an ion-absorbed rare earth ore by ameliorating the seepage effect for the first time.The effects of surfactant concentration,leaching agent dosage,solution flow velocity,and solution pH on the leaching rate were explored,and the mechanism of SDS was discussed.Under the optimum conditions,the addition of a small amount of SDS(mass fraction0.04%) can increase the leaching rate by about 5%,shorten the leaching period,and reduce the consumption of the leaching agent.SDS significantly ameliorates the seepage effect of the ore body by reducing the surface tension of the leaching agent and ameliorating the wettability of the mineral surface.This effect is the main factor that improves the leaching efficiency.DFT(density functional theory) calculation results show that SDS can react with rare earth ions,which reduces the adsorption strength on clay mineral surfaces.Hence,rare earth ions are easily exchanged by ammonium ions,and mass transfer is enhanced.
文摘A sensitive and simple solid phase extraction method for the simultaneous determination of trace and toxic metals in environmental samples has been reported. The method is based on the adsorption of Zinc, Iron and Copper on SDS-coated alumina nanoparticles, which is also modified with 3-mercapto-D-valine. The retained analyte ions on modified solid phase were eluted using 5 mL of 4 mol·L﹣1 HNO3. The analyte determination was carried out by flame atomic absorption spectrometry. The influences of some metal ion and anions on the recoveries of understudy analyte ion were investigated. The influences of the analytical parameters including pH, ligand and SDS amount, eluting solution (type and concentrations) and sample volume on metal ions recoveries were investigated. The extraction efficiency was > 98% with relative standard deviation lower than 3% the method has been successfully applied for the extraction and determination of these ions content in some real samples. Prepared adsorbent was characterized by SEM and FT-IR measurements.
文摘This study is to prepare chitosan beads modified with sodium dodecyl sulfate (SDS) to effectively remove Cr(III) from an aqueous solution. The characterizations of SDS-chitosan by scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), Fourier transform-infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) proved the successful synthesis of the adsorbent. The adsorption of Cr(III) on the SDS material was investigated by varying experimental conditions such as pH, contact time and adsorbent dosage. The maximum adsorption capacity of SDS-chitosan for Cr(III) was estimated to be 3.42 mg?g<sup>-1</sup>. The results of adsorption kinetics and isothermal models show that the adsorption process conforms to the pseudo-second-order and Langmuir isotherm models, indicating that the adsorption is single-layer chemical adsorption. Thermodynamic analyses indicate that the adsorption of Cr(III) is an endothermic reaction. These results show that the new adsorbent has obvious application prospect to eliminate Cr(III).
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61575178 and 11574272)Zhejiang Provincial Natural Science Foundation of China(Grant No.LY16A040014)the Scientific Research and Developed Fund of Zhejiang A&F University,China(Grant No.2015FR022)
文摘Molecular dynamics simulations have been performed on the fully hydrated lipid bilayer with different concentrations of sodium dodecyl sulfate （SDS）. SDS can readily penetrate into the membrane. The insertion of SDS causes a decrease in the bilayer area and increases in the bilayer thickness and lipid tail order, when the fraction of SDS is less than 28%. Through calculating the binding energy, we confirm that the presence of SDS strengthens the interactions among the DPPC lipids, while SDS molecules act as intermedia. Both the strong hydrophilic interactions between sulfate and phosphocholine groups and the hydrophobic interactions between SDS and DPPC hydrocarbon chains contribute to the tight packing and ordered alignment of the lipids. These results are in good agreement with the experimental observations and provide atomic level information that complements the experiments.
文摘The electrooxidation of tetracycline (TC) at acetylene black electrode has been studied in the presence of sodium dodecyl sulfate (SDS). Tetracycline (TC) exhibited very sensitive oxidation peak in this system. The peak current was proportional to TC concentration, and the detection limit was 1.2×10-8 mol/L. The system was used to the determination of TC in Pharmaceuticals.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11334005 and 11574150
文摘Dynamics of a single cavitation bubble in sodium dodecyl sulfate（SDS） aqueous solutions is investigated experimentally and theoretically. The bubble pulsation is measured by a phase-locked integrated imaging technique,and the ambient radius is obtained by fitting the numerical calculation based on the Rayleigh–Plesset bubble dynamics model to the experimental data. The results show that, under the same driving condition, the ambient radius of the cavitation bubble decreases correspondingly with the increase of SDS concentration within the critical micelle concentration, while the compression ratio of the radius increases, which indicates that the addition of SDS decreases the internal molecular number of the cavitation bubble and increases the power capability of the cavitation bubble. In addition, bubble oscillation increases the concentration of the surfactant molecules on the bubble wall, so that the effect of SDS on a single cavitation bubble is reduced when the SDS concentration is greater than 0.8 m M.
文摘目的:建立快速、简便测定鲜牛奶、转基因牛奶和人乳中乳铁蛋白的方法。方法:在对样品脱脂和去除酪蛋白时,水洗乳脂、酪蛋白以提高乳铁蛋白的回收率。通过十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(sodiumdodecyl sulfate-polyacrylamide gel electrophoresis,SDS-PAGE)分离乳清蛋白,薄层扫描法定量。对电泳和薄层扫描的条件进行优化,电泳使用1.0mm×10齿的试样格、分离胶质量浓度12g/mL、分离电压100V、上样量5μL、染色3h、脱色2h;薄层扫描采取锯齿、双波长、透射的扫描方式,Y步长和摆幅宽分别为0.1mm和8mm。结果:可以分离不同来源乳中的乳铁蛋白、α-乳白蛋白和β-乳球蛋白;乳铁蛋白加标回收率分别为104.53%、108.37%,同板精密度RSD值为3.1003%和1.8151%,在100～2000μg/mL范围内呈线性关系,相关系数为0.9988和0.9990。结论:此方法可以用于3种乳中乳铁蛋白的测定。
文摘甲烷水合物蓄冷量的确定是甲烷水合物蓄冷降温技术实现工业化的关键.为探究SDS对甲烷水合物蓄冷量的影响,根据Clausius-Clapeyron方程及三参数对应态原理,建立甲烷水合物蓄冷量的计算模型.利用可视化水合物蓄冷实验系统,结合定温压力搜索法测定四组不同SDS浓度体系下甲烷水合物的相平衡条件.依据实验数据和该模型计算得到不同体系、不同相平衡参数下甲烷水合物的蓄冷量.结果表明：甲烷水合物具有较高的蓄冷密度,蓄冷量达40～ 60 k J/mol;甲烷水合物的蓄冷量不但与相平衡条件有关,还与SDS的添加浓度有关.相平衡温度越高、SDS添加浓度越高,甲烷气体生成水合物时蓄冷量越低.该研究为甲烷水合物蓄冷降温系统的研制提供了参考.
