A coupled chemiluminescence method for the determination of some carhoxylic acids was devel-oped, based on their enhancement the chemiluminescence light emission of the reaction of tirs(2, 2'-bipyri-dine) rutheni...A coupled chemiluminescence method for the determination of some carhoxylic acids was devel-oped, based on their enhancement the chemiluminescence light emission of the reaction of tirs(2, 2'-bipyri-dine) ruthenium(Ⅱ) and Ce(Ⅳ) in sulfuric acid medium. The conditions for their determination were opti-mized. The following detection limits were obtained: oxalic acid, 2. 67×10-8 mol/L; propandioic acld, 1.20×10-6 mol/L; pyruvic acid, 1. 35 ×10-8 mol/L; citric acid, 5.10×10-8. mol/L; barbituric acid, 2.48×10-7,mol/L. The proposed method was successfully applied to determination or oxalic acid. The coupled chemilu-minescent reaction mechanism and rate equation are proposed.展开更多
Electrolytic manganese metal residue(EMMR)harmless treatment has always lacked a low-cost and quick processing technology.In this study,surfactants,namely tetradecyl trimethylammonium chloride(TTC),sodium dodecyl benz...Electrolytic manganese metal residue(EMMR)harmless treatment has always lacked a low-cost and quick processing technology.In this study,surfactants,namely tetradecyl trimethylammonium chloride(TTC),sodium dodecyl benzene sulfonate(SDBS),sodium lignin sulfonate(SLS),and octadecyl trimethylammonium chloride(OTC),were used in the solidification of Mn^(2+)and removal of NH_(4)^(+)-N from EMMR.The Mn^(2+)and NH_(4)^(+)-N concentrations under different reaction conditions,Mn^(2+)solidification and NH_(4)^(+)-N removal mechanisms,and leaching behavior were studied.The results revealed that the surfactants could enhance the Mn^(2+)solidification and NH_(4)^(+)-N removal from EMMR,and the order of enhancement was as follows:TTC>SDBS>OTC>SLS.The NH_(4)^(+)-N and Mn^(2+)concentrations were 12.3 and 0.05 mg·L^(-1)with the use of 60.0 mg·kg^(-1)TTC under optimum conditions(solid–liquid ratio of 1.5:1,EMMR to BRM mass ratio of 100:8,temperature of 20℃,and reaction duration of 12 h),which met the integrated wastewater discharge standard(GB8978-1996).Mn^(2+)was mainly solidified as Mn(OH)_(2),MnOOH and MnSiO_(3),and NH_(4)^(+)-N in EMMR was mostly removed in the form of ammonia.The results of this study could provide a new idea for cost-effective EMMR harmless treatment.展开更多
A novel high performance liquid chromatography-chemiluminescence（HPLC-CL） method for investigation of in vitro metabolism of repaglinide in pig liver microsomes with microdialysis sampling technique was developed.Th...A novel high performance liquid chromatography-chemiluminescence（HPLC-CL） method for investigation of in vitro metabolism of repaglinide in pig liver microsomes with microdialysis sampling technique was developed.The chromatographic separation was performed on a Hypersil BDS-C18 column with an isocratic mobile phase consisting of methanol and 0.01 mol/L KH_2PO_4（pH 3.0）（volume ratio 75：25） at a flow rate of 1.0 mL/min.The detection was based on the chemiluminescence reaction of repaglinide with acidic potassium permanganate（KMnO_4） and tris（2,2＇-bipyridyl）ruthenium（Ⅲ）（Ru（bpy）_3^（3＋））,which was immobilized on the cationic ion-exchange resin for obtaining high sensitivity and reducing consumption of expensive reagent.展开更多
准确识别和定量挥发性有机化合物(volatile organic compounds,VOCs)氧化中间产物(包括闭壳产物和有机过氧自由基RO_(2)),对于厘清其降解机理和实现二次物种精准模拟与精细化管控十分关键.本研究基于最新开发的质子转移反应-飞行时间质...准确识别和定量挥发性有机化合物(volatile organic compounds,VOCs)氧化中间产物(包括闭壳产物和有机过氧自由基RO_(2)),对于厘清其降解机理和实现二次物种精准模拟与精细化管控十分关键.本研究基于最新开发的质子转移反应-飞行时间质谱,结合高选择性的铵根离子加成模式,发展了铵根-电离质谱法(ammonium chemical ionization mass spectrometry,NH_(4)^(+)-CIMS),成功实现了对不同种类的RO_(2)自由基以及含氧VOCs物种的高灵敏度检测.通过自主搭建的标定系统,实现了基于质谱法测量RO_(2)自由基的直接标定,有效降低了由于灵敏度替代造成的测量不确定性.该套系统首先应用于近实际大气条件下α-蒎烯臭氧氧化体系的研究,共检测到13种一代反应产物,包括5种RO_(2)自由基和8种闭壳物种,其中来自OH氧化反应生成的过氧自由基C_(10)H_(17)O_(3)占比最大,臭氧氧化α-蒎烯生成的过氧自由基C_(10)H_(15)O_(4)发生多步自氧化及双分子反应,生成含更高氧数的过氧自由基和闭壳产物,证实了α-蒎烯自氧化反应通道的重要性.现有大气化学机理可基本捕捉α-蒎烯臭氧化反应的产物分布,但不同氧化通道产物的相对占比受模型设置的反应速率和反应通道分支比影响存在较大不确定性.此外,氢摘取通道可能对OH自由基氧化α-蒎烯具有重要贡献,但机制待进一步探索.本研究展示的NH_(4)^(+)化学电离质谱技术,具有高灵敏度、高分辨率、低检测限等优点,特别是对中等氧化程度的闭壳产物和RO_(2)自由基的检测.未来,这套系统有望在更复杂的大气环境中揭示VOCs的演化规律和降解机制,为大气环境保护提供重要科学依据.展开更多
Atomic sites co-catalyst (ASC) on photocatalytic materials possesses an attractive prospect to promote charge carrier separation and tune surface reaction kinetics,yet the synthesis of earth-abundant ASC under low tem...Atomic sites co-catalyst (ASC) on photocatalytic materials possesses an attractive prospect to promote charge carrier separation and tune surface reaction kinetics,yet the synthesis of earth-abundant ASC under low temperature remains a great challenge.Here,a novel in-situ NH_(4)^(+)-etched strategy to anchor atomic Mo sites on ZnIn_(2)S_(4)hierarchical nanotubes (HNTs) with abundant mesopores under mild conditions for promoting charge carrier separation and enhancing light multi-reflections is developed for efficient photocatalytic H_(2) evolution.Density functional theory calculations and linear sweep voltammetry demonstrate that the well-defined Mo-S_(2)O_(1) sites with distinctive coordination configuration and electronic property contribute to the enhanced separation of photo-generated charge carriers and reduced Gibbs free energy for H_(2) evolution.Consequently,the well-defined MoSA-ZIS HNTs present an excellent photocatalytic activity with a rate of 29.9μmol h^(-1)(5.98 mmol g^(-1)h^(-1)),which is 7.3 times higher than that of ZnIn_(2)S_(4)nanosheets (NSs),to be among the best ZnIn_(2)S_(4)-based photocatalysts.The present strategy breaks the high-temperature limitation of conventional top-down thermal dissociation/emitting approach for anchoring non-noble metal atomic sites on catalyst support.展开更多
A sensitive and selective method employing chemiluminescence(CL)coupled with flow injection(FI)is reported for nalbuphine hydrochloride(NAL)assay in pharmaceutical formulations.The enhancement effect of NAL on the CL ...A sensitive and selective method employing chemiluminescence(CL)coupled with flow injection(FI)is reported for nalbuphine hydrochloride(NAL)assay in pharmaceutical formulations.The enhancement effect of NAL on the CL reaction between tris(2,2′-bipyridyl)ruthenium(II)chloride-diperiodatocuprate(III){Ru[(bpy)_(3)]^(2+)-Cu(III)complex}in acidic medium is used as analytical measurement.The optimal conditions of the CL reaction were sulfuric acid 1.0×10^(−3) mol/L,Ru[(bpy)s]2+7.5×10^(−5) mol/L,Cu(III)/Ag(III)complexes 4.0×10^(−4)/5.0×10^(−4) mol/L,sample loop volume of 120µL and flow rate of 2.5 mL/min.The sensitivities of the method in terms of detection(S/N=3)and quantification(S/N=10)limits are 5×10^(−4) and 0.001 ppm(1 ppm=1 mg/L),respectively.The linear response of the instrument in the form of CL intensity with respect to NAL concentration is over the range 0.001-15.0 ppm(R^(2)=0.9999)with relative standard deviation from 0.8%to 3.2%and injection throughput of 120 injection/h.The applications of the method include the quantitative analysis of NAL in pharmaceutical injection samples.Variations and the average results of the proposed method are not significantly different from the results of a reported method by applying F-and paired student t-test.The most likely CL reaction mechanism is written in accordance with spectrophotometric and CL studies.展开更多
文摘A coupled chemiluminescence method for the determination of some carhoxylic acids was devel-oped, based on their enhancement the chemiluminescence light emission of the reaction of tirs(2, 2'-bipyri-dine) ruthenium(Ⅱ) and Ce(Ⅳ) in sulfuric acid medium. The conditions for their determination were opti-mized. The following detection limits were obtained: oxalic acid, 2. 67×10-8 mol/L; propandioic acld, 1.20×10-6 mol/L; pyruvic acid, 1. 35 ×10-8 mol/L; citric acid, 5.10×10-8. mol/L; barbituric acid, 2.48×10-7,mol/L. The proposed method was successfully applied to determination or oxalic acid. The coupled chemilu-minescent reaction mechanism and rate equation are proposed.
基金supported by National Natural Science Foundation of China(52174386,21806132)the National Key Research and Development Program of China(2018YFC1903500)+1 种基金the Science and Technology Plan Project of Sichuan Province(2021YFH0058)the Key Research and Development Program of Guangxi Province(AB18126088)。
文摘Electrolytic manganese metal residue(EMMR)harmless treatment has always lacked a low-cost and quick processing technology.In this study,surfactants,namely tetradecyl trimethylammonium chloride(TTC),sodium dodecyl benzene sulfonate(SDBS),sodium lignin sulfonate(SLS),and octadecyl trimethylammonium chloride(OTC),were used in the solidification of Mn^(2+)and removal of NH_(4)^(+)-N from EMMR.The Mn^(2+)and NH_(4)^(+)-N concentrations under different reaction conditions,Mn^(2+)solidification and NH_(4)^(+)-N removal mechanisms,and leaching behavior were studied.The results revealed that the surfactants could enhance the Mn^(2+)solidification and NH_(4)^(+)-N removal from EMMR,and the order of enhancement was as follows:TTC>SDBS>OTC>SLS.The NH_(4)^(+)-N and Mn^(2+)concentrations were 12.3 and 0.05 mg·L^(-1)with the use of 60.0 mg·kg^(-1)TTC under optimum conditions(solid–liquid ratio of 1.5:1,EMMR to BRM mass ratio of 100:8,temperature of 20℃,and reaction duration of 12 h),which met the integrated wastewater discharge standard(GB8978-1996).Mn^(2+)was mainly solidified as Mn(OH)_(2),MnOOH and MnSiO_(3),and NH_(4)^(+)-N in EMMR was mostly removed in the form of ammonia.The results of this study could provide a new idea for cost-effective EMMR harmless treatment.
基金supported financially by the Fundamental Research Funds for the Central Universities(No. GK20091004)
文摘A novel high performance liquid chromatography-chemiluminescence（HPLC-CL） method for investigation of in vitro metabolism of repaglinide in pig liver microsomes with microdialysis sampling technique was developed.The chromatographic separation was performed on a Hypersil BDS-C18 column with an isocratic mobile phase consisting of methanol and 0.01 mol/L KH_2PO_4（pH 3.0）（volume ratio 75：25） at a flow rate of 1.0 mL/min.The detection was based on the chemiluminescence reaction of repaglinide with acidic potassium permanganate（KMnO_4） and tris（2,2＇-bipyridyl）ruthenium（Ⅲ）（Ru（bpy）_3^（3＋））,which was immobilized on the cationic ion-exchange resin for obtaining high sensitivity and reducing consumption of expensive reagent.
文摘准确识别和定量挥发性有机化合物(volatile organic compounds,VOCs)氧化中间产物(包括闭壳产物和有机过氧自由基RO_(2)),对于厘清其降解机理和实现二次物种精准模拟与精细化管控十分关键.本研究基于最新开发的质子转移反应-飞行时间质谱,结合高选择性的铵根离子加成模式,发展了铵根-电离质谱法(ammonium chemical ionization mass spectrometry,NH_(4)^(+)-CIMS),成功实现了对不同种类的RO_(2)自由基以及含氧VOCs物种的高灵敏度检测.通过自主搭建的标定系统,实现了基于质谱法测量RO_(2)自由基的直接标定,有效降低了由于灵敏度替代造成的测量不确定性.该套系统首先应用于近实际大气条件下α-蒎烯臭氧氧化体系的研究,共检测到13种一代反应产物,包括5种RO_(2)自由基和8种闭壳物种,其中来自OH氧化反应生成的过氧自由基C_(10)H_(17)O_(3)占比最大,臭氧氧化α-蒎烯生成的过氧自由基C_(10)H_(15)O_(4)发生多步自氧化及双分子反应,生成含更高氧数的过氧自由基和闭壳产物,证实了α-蒎烯自氧化反应通道的重要性.现有大气化学机理可基本捕捉α-蒎烯臭氧化反应的产物分布,但不同氧化通道产物的相对占比受模型设置的反应速率和反应通道分支比影响存在较大不确定性.此外,氢摘取通道可能对OH自由基氧化α-蒎烯具有重要贡献,但机制待进一步探索.本研究展示的NH_(4)^(+)化学电离质谱技术,具有高灵敏度、高分辨率、低检测限等优点,特别是对中等氧化程度的闭壳产物和RO_(2)自由基的检测.未来,这套系统有望在更复杂的大气环境中揭示VOCs的演化规律和降解机制,为大气环境保护提供重要科学依据.
基金the Beijing Natural Science Foundation(JQ18005)the National Science Fund for Distinguished Young Scholars(52025133)+3 种基金the Tencent Foundation through the XPLORER PRIZEthe National Natural Science Foundation of China(22002003)China Postdoctoral Science Foundation(2019TQ0001,2020M670020)the Fund of the State Key Laboratory of Solidification Processing in Northwestern Polytechnic University(NWPU)(SKLSP202004)。
文摘Atomic sites co-catalyst (ASC) on photocatalytic materials possesses an attractive prospect to promote charge carrier separation and tune surface reaction kinetics,yet the synthesis of earth-abundant ASC under low temperature remains a great challenge.Here,a novel in-situ NH_(4)^(+)-etched strategy to anchor atomic Mo sites on ZnIn_(2)S_(4)hierarchical nanotubes (HNTs) with abundant mesopores under mild conditions for promoting charge carrier separation and enhancing light multi-reflections is developed for efficient photocatalytic H_(2) evolution.Density functional theory calculations and linear sweep voltammetry demonstrate that the well-defined Mo-S_(2)O_(1) sites with distinctive coordination configuration and electronic property contribute to the enhanced separation of photo-generated charge carriers and reduced Gibbs free energy for H_(2) evolution.Consequently,the well-defined MoSA-ZIS HNTs present an excellent photocatalytic activity with a rate of 29.9μmol h^(-1)(5.98 mmol g^(-1)h^(-1)),which is 7.3 times higher than that of ZnIn_(2)S_(4)nanosheets (NSs),to be among the best ZnIn_(2)S_(4)-based photocatalysts.The present strategy breaks the high-temperature limitation of conventional top-down thermal dissociation/emitting approach for anchoring non-noble metal atomic sites on catalyst support.
文摘A sensitive and selective method employing chemiluminescence(CL)coupled with flow injection(FI)is reported for nalbuphine hydrochloride(NAL)assay in pharmaceutical formulations.The enhancement effect of NAL on the CL reaction between tris(2,2′-bipyridyl)ruthenium(II)chloride-diperiodatocuprate(III){Ru[(bpy)_(3)]^(2+)-Cu(III)complex}in acidic medium is used as analytical measurement.The optimal conditions of the CL reaction were sulfuric acid 1.0×10^(−3) mol/L,Ru[(bpy)s]2+7.5×10^(−5) mol/L,Cu(III)/Ag(III)complexes 4.0×10^(−4)/5.0×10^(−4) mol/L,sample loop volume of 120µL and flow rate of 2.5 mL/min.The sensitivities of the method in terms of detection(S/N=3)and quantification(S/N=10)limits are 5×10^(−4) and 0.001 ppm(1 ppm=1 mg/L),respectively.The linear response of the instrument in the form of CL intensity with respect to NAL concentration is over the range 0.001-15.0 ppm(R^(2)=0.9999)with relative standard deviation from 0.8%to 3.2%and injection throughput of 120 injection/h.The applications of the method include the quantitative analysis of NAL in pharmaceutical injection samples.Variations and the average results of the proposed method are not significantly different from the results of a reported method by applying F-and paired student t-test.The most likely CL reaction mechanism is written in accordance with spectrophotometric and CL studies.
