A laboratory-scale investigation was performed to study arsenic(As(V))removal by negatively charged GE-HL nanofiltration(NF)membrane in simulated drinking water.Effects of As(V)concentration(0–200μg·L–1),pH,an...A laboratory-scale investigation was performed to study arsenic(As(V))removal by negatively charged GE-HL nanofiltration(NF)membrane in simulated drinking water.Effects of As(V)concentration(0–200μg·L–1),pH,and co-ions and counter-ions were investigated.The NF membrane presented good stability,and the rejection rates exceeded 90%.The rejection rates of As(V)decreased with the increase of As(V)concentration,while it increased with the increase of pH(reached 96%at pH 6.75).Moreover,a negative relationship was observed between the co-existing ions of Cl^(–),Na^(+),SO_(4)^(2–),and Ca^(2+)and the removal of As(V),in which bivalent ions presented more significant effects than monovalent ions.展开更多
Irreversible reductive insertion of Zn2+transforms Mn3O4 such that the resulting Zn0.2Mn3O4 exhibits highly reversible storage properties of chloride ions,thus rendering Zn0.2Mn3O4 an excellent cathode of aqueous dual...Irreversible reductive insertion of Zn2+transforms Mn3O4 such that the resulting Zn0.2Mn3O4 exhibits highly reversible storage properties of chloride ions,thus rendering Zn0.2Mn3O4 an excellent cathode of aqueous dual-ion batteries.With Zn2+trapped,Zn0.2Mn3O4 delivers the chloride-storage capacity over 200 mAh/g at an average potential of 1.6 V vs Zn2+/Zn by reversibly forming a new ionic compound equivalent to Zn0.2Mn3O4Cl1.7.Electrochemical quartz crystal microbalance results suggest chloride as the primary charge carrier in the reversible oxidative anion insertion.The Mn3O4 anion-hosting cathode couples with Zn metal anode in a full-cell dual-ion battery,demonstrating stable cycling in practical pouch cells with an energy density of 150 Wh/kg based on the mass of both electrodes.展开更多
The surface tension, foaming and viscosity for C7F15COO^-N^＋H（C2H4OH）χ（C2Hs）3-x and C8F17SO3- N^＋H（C2H4OH）χ（C2H5）3-χ （x = 0, 1, 2, 3） were measured to systematically study the effects of hydroxyl groups...The surface tension, foaming and viscosity for C7F15COO^-N^＋H（C2H4OH）χ（C2Hs）3-x and C8F17SO3- N^＋H（C2H4OH）χ（C2H5）3-χ （x = 0, 1, 2, 3） were measured to systematically study the effects of hydroxyl groups in organic ammonium counterions on the properties of perfluorooctanoates and perfluorooctanesulfonates. The results showed that the critical micelle concentration （cmc） and the surface tension at cmc （γcmc） were both increased with the increase of number of hydroxyl groups （χ） in the two series. The perfluorooctanesulfonate had smaller cmc but higher γ=cmc than perfluorooctanoate with the same counterion. The minimum molecular area of surface adsorption （Amin） of C8F17zSO3^-N^＋H（C2H4OH）χ（C2H5）3-χ were 0.64, 0.57, 0.63 and 0.72 nm^2 while the Amin values of C7F15COO^-N^＋H（C2H4OH）χ（C2H5）3-χ were 0.61, 0.62, 0.61 and 0.71 nm^2 when χ = 0, 1, 2 and 3, respectively. For the investigated systems of surfactants, the results of foam expansion ratio agreed with those of surface activity, while the 25% drainage time were consistent with the results of viscosity.展开更多
Chitosan microparticles for controlling drug delivery have been prepared by water in oil(w/o)emulsification process.Glutaraldehyde is normally used as cross-linking agent for hardening chitosan polymer into the rigid ...Chitosan microparticles for controlling drug delivery have been prepared by water in oil(w/o)emulsification process.Glutaraldehyde is normally used as cross-linking agent for hardening chitosan polymer into the rigid particles[1].From the cationic charge of ammonium groups in chitosan structure,moreover,it is also possible to cross-link the polymeric chain by the anionic counter-ion substances.Sodium hydroxide(NaOH)and tripolyphosphate(TPP)are the rich negatively charged molecules that are normally used in pharmaceutical preparations.They might be more appropriate to be chosen for the co-crosslinking process due to its safety[2].Therefore,this study aimed to investigate the effect of counter-ion NaOH and TPP agents on the properties of chitosan microparticles crosslinked by glutaraldehyde.Metronidazole was used as model drug loaded in these systems.展开更多
Protonating the pyridine rings of poly(pyridine-2,5-diyl) with dodecybenzenesulfonic acid and camphorsulphonic acid produces polymer materials which can be dissolved in chloroform (in contrast to the unprotonated poly...Protonating the pyridine rings of poly(pyridine-2,5-diyl) with dodecybenzenesulfonic acid and camphorsulphonic acid produces polymer materials which can be dissolved in chloroform (in contrast to the unprotonated polymer, which can only be dissolved in strong acids such as formic acid) and allows mixing the protonated polymers with other chloroform soluble conju- gated polymers for use in electronic devices. The protonating behavior of poly(pyridine-2,5-diyl) with two kinds of surfactants is different in some levels. Dodecybenzenesulfonic acid has higher protonating ability than camphorsulphonic acid.展开更多
Both critical micelle concentration(CMC)and the counter-ion association degree (K) of aqueous cationic surfactants solutions (DTMAC,DTAC,TTAC,CTAC,OTAC)could be determined simultaneously by chloride ISE.The experiment...Both critical micelle concentration(CMC)and the counter-ion association degree (K) of aqueous cationic surfactants solutions (DTMAC,DTAC,TTAC,CTAC,OTAC)could be determined simultaneously by chloride ISE.The experimental results showed that the CMC were in agreement with the literature value.ISE was both simple and quick,and the results were accurate,reliable and satisfied.The reasons for the differences between the results obtained from both ISE and conductance methods were also discussed in detail in this paper.展开更多
本文获得了由长链氧化胺表面活性剂LAO与反离子盐复配形成的清洁胶束压裂液体系,并进一步研究了该体系流变性能、耐温性能及其相关影响因素。结果表明,LAO清洁压裂液最优组成为2%LAO+3%水杨酸钠(NaSal),该体系的耐温极限为120℃。该体系...本文获得了由长链氧化胺表面活性剂LAO与反离子盐复配形成的清洁胶束压裂液体系,并进一步研究了该体系流变性能、耐温性能及其相关影响因素。结果表明,LAO清洁压裂液最优组成为2%LAO+3%水杨酸钠(NaSal),该体系的耐温极限为120℃。该体系在110℃、170 s^(-1)下剪切1 h后,体系黏度可保持在30 m Pa·s以上。同时,该体系具有良好的携砂性能和明显的黏弹性、触变性和剪切变稀特性。破胶实验表明,在压裂液与原油体积比不大于40:1时,原油可使该体系顺利破胶,破胶液黏度小于3 m Pa·s。展开更多
基金the Alcoa fund and Beijing Municipal Science and Technology Commission(Z0006345000091)。
文摘A laboratory-scale investigation was performed to study arsenic(As(V))removal by negatively charged GE-HL nanofiltration(NF)membrane in simulated drinking water.Effects of As(V)concentration(0–200μg·L–1),pH,and co-ions and counter-ions were investigated.The NF membrane presented good stability,and the rejection rates exceeded 90%.The rejection rates of As(V)decreased with the increase of As(V)concentration,while it increased with the increase of pH(reached 96%at pH 6.75).Moreover,a negative relationship was observed between the co-existing ions of Cl^(–),Na^(+),SO_(4)^(2–),and Ca^(2+)and the removal of As(V),in which bivalent ions presented more significant effects than monovalent ions.
文摘Irreversible reductive insertion of Zn2+transforms Mn3O4 such that the resulting Zn0.2Mn3O4 exhibits highly reversible storage properties of chloride ions,thus rendering Zn0.2Mn3O4 an excellent cathode of aqueous dual-ion batteries.With Zn2+trapped,Zn0.2Mn3O4 delivers the chloride-storage capacity over 200 mAh/g at an average potential of 1.6 V vs Zn2+/Zn by reversibly forming a new ionic compound equivalent to Zn0.2Mn3O4Cl1.7.Electrochemical quartz crystal microbalance results suggest chloride as the primary charge carrier in the reversible oxidative anion insertion.The Mn3O4 anion-hosting cathode couples with Zn metal anode in a full-cell dual-ion battery,demonstrating stable cycling in practical pouch cells with an energy density of 150 Wh/kg based on the mass of both electrodes.
基金supported by the Applied Chemistry Key Subject of Gansu Province (No. GSACKS20130113)Youth Science and Technology Innovation Project of Longdong University (No.XYZK1512, No.XYZK1511)
文摘The surface tension, foaming and viscosity for C7F15COO^-N^＋H（C2H4OH）χ（C2Hs）3-x and C8F17SO3- N^＋H（C2H4OH）χ（C2H5）3-χ （x = 0, 1, 2, 3） were measured to systematically study the effects of hydroxyl groups in organic ammonium counterions on the properties of perfluorooctanoates and perfluorooctanesulfonates. The results showed that the critical micelle concentration （cmc） and the surface tension at cmc （γcmc） were both increased with the increase of number of hydroxyl groups （χ） in the two series. The perfluorooctanesulfonate had smaller cmc but higher γ=cmc than perfluorooctanoate with the same counterion. The minimum molecular area of surface adsorption （Amin） of C8F17zSO3^-N^＋H（C2H4OH）χ（C2H5）3-χ were 0.64, 0.57, 0.63 and 0.72 nm^2 while the Amin values of C7F15COO^-N^＋H（C2H4OH）χ（C2H5）3-χ were 0.61, 0.62, 0.61 and 0.71 nm^2 when χ = 0, 1, 2 and 3, respectively. For the investigated systems of surfactants, the results of foam expansion ratio agreed with those of surface activity, while the 25% drainage time were consistent with the results of viscosity.
文摘Chitosan microparticles for controlling drug delivery have been prepared by water in oil(w/o)emulsification process.Glutaraldehyde is normally used as cross-linking agent for hardening chitosan polymer into the rigid particles[1].From the cationic charge of ammonium groups in chitosan structure,moreover,it is also possible to cross-link the polymeric chain by the anionic counter-ion substances.Sodium hydroxide(NaOH)and tripolyphosphate(TPP)are the rich negatively charged molecules that are normally used in pharmaceutical preparations.They might be more appropriate to be chosen for the co-crosslinking process due to its safety[2].Therefore,this study aimed to investigate the effect of counter-ion NaOH and TPP agents on the properties of chitosan microparticles crosslinked by glutaraldehyde.Metronidazole was used as model drug loaded in these systems.
文摘Protonating the pyridine rings of poly(pyridine-2,5-diyl) with dodecybenzenesulfonic acid and camphorsulphonic acid produces polymer materials which can be dissolved in chloroform (in contrast to the unprotonated polymer, which can only be dissolved in strong acids such as formic acid) and allows mixing the protonated polymers with other chloroform soluble conju- gated polymers for use in electronic devices. The protonating behavior of poly(pyridine-2,5-diyl) with two kinds of surfactants is different in some levels. Dodecybenzenesulfonic acid has higher protonating ability than camphorsulphonic acid.
文摘Both critical micelle concentration(CMC)and the counter-ion association degree (K) of aqueous cationic surfactants solutions (DTMAC,DTAC,TTAC,CTAC,OTAC)could be determined simultaneously by chloride ISE.The experimental results showed that the CMC were in agreement with the literature value.ISE was both simple and quick,and the results were accurate,reliable and satisfied.The reasons for the differences between the results obtained from both ISE and conductance methods were also discussed in detail in this paper.
文摘本文获得了由长链氧化胺表面活性剂LAO与反离子盐复配形成的清洁胶束压裂液体系,并进一步研究了该体系流变性能、耐温性能及其相关影响因素。结果表明,LAO清洁压裂液最优组成为2%LAO+3%水杨酸钠(NaSal),该体系的耐温极限为120℃。该体系在110℃、170 s^(-1)下剪切1 h后,体系黏度可保持在30 m Pa·s以上。同时,该体系具有良好的携砂性能和明显的黏弹性、触变性和剪切变稀特性。破胶实验表明,在压裂液与原油体积比不大于40:1时,原油可使该体系顺利破胶,破胶液黏度小于3 m Pa·s。
