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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye Li Shuang Pan Yihuang Chen Qiong Liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Free radical reactions

Fabrication of the electrochemically reduced graphene oxide-bismuth nanoparticles composite and its analytical application for an anticancer drug gemcitabine

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Chinese Chemical Letters 2017年第7期28卷 1429-1437页

作者： Ranjita Tandel Nagappa Teradal Ashis Satpati Seetharamappa Jaldappagari Department of Chemistry Karnatak University analytical Chemistry Division Bhabha Atomic Research Center

The present study explores an electroreduced graphene oxide-bismuth nanoparticles composite（ErGOBi） as an electrochemical sensor for the determination of an anticancer drug, gemcitabine hydrochloride（GMB）. The Er-GOBi interface was prepared by drop casting of bismuth nitrate-graphene oxide suspension on a glassy carbon electrode（GCE） followed by electro-reduction in the potential range of 0.6 V to 1.7 V. SEM, FTIR, EDAX and AFM techniques were employed for the characterization of prepared materials. Cyclic voltammetric and electrochemical impedance spectroscopic methods were used to understand the charge transfer properties of stepwise modification of Er-GOBi/GCE. GMB exhibited an irreversible oxidation peak at 1.144 V on Er-GOBi/GCE in phosphate buffer of p H 3. A 100-fold enhanced oxidation peak current was observed at Er-GOBi/GCE when compared to that at bare *** performance of Er GO-Bi/GCE was optimized by varying peak current dependent *** relationship between the peak current and concentration of GMB was observed in the range of 0.1–51.1 mmol/L in differential pulse voltammetric method and 2.1–61.1 mmol/L in linear sweep voltammetric method. The practical utility of the proposed sensor, Er-GOBi/GCE was demonstrated by determining GMB in pharmaceutical formulations and spiked urine samples.

关键词： Gemcitabine Nanocomposite Electrochemical sensor Pharmaceutical formulations Graphene oxide

The new approach of standardization of capillary electrophoresis

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Science China Chemistry 2005年第Z1期48卷 14-19页

作者： JOSEF Havel Department of analytical Chemistry

In this paper, we develope the new standardization methods to eliminate the influence in capillary electrophoresis (CE). The markers were used to determine the basis position and then correct the data of sample by the migration time of standard sample, and make the migration time of samples consistent with the standard sample by the criterion of the marker. The problem of time transition was corrected in this way. Then according to the peak height or peak area of the marker in the sample (peak height was used here) compared with the standard sample, the sample data was zoomed appropriately. The absorbance error was made to be *** wavelet de-noise method was also used to make the data smooth and get a good baseline.

关键词： capillary electrophoresis, standardization, precision, qualitative and quantitative analysis, wavelet transform.

An analytical Expression of Magic Angle Spinning Nuclear Magnetic Resonance Free Induction Decay in Two-Site Exchange Problem

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Chinese Physics Letters 1998年第6期15卷 453-454页

作者： SHEN Yi-min KAJI Hironori HORII Fumitaka analytical Center Fudan UniversityShanghai 200433 Institute for Chemical Research Kyoto UniversityUjiKyoto 611Japan

An analytical expression of free induction decay has been derived for calculating the magic angle spinning sideband patterns of nuclear magnetic resonance spectra in a two-site exchange *** expression has been confirmed by comparing the calculated spinning sideband patterns for powdered crystalline dimethyl sulfone at different exchange rates with experimentally measured spectra at various temperatures.

关键词： exchange spectra crystalline

Ion behavior and interelectrode breakdown voltage of a drift tube

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Chinese Physics C 2015年第5期39卷 98-104页

作者：耿浩赵忠俊段忆翔 Research Center of analytical Instrumentation Analytical & Testing Center Sichuan University Research Center of analytical Instrumentation College of Chemistry Sichuan University Research Center of analytical Instrumentation College of Life Science Sichuan University

We experimentally studied ion behavior and interelectrode breakdown voltage. The ion behavior of a drift tube directly influences the detection of ion intensity, and then influences the detection sensitivity of a system. Interelectrode voltage and pressure directly influence the ion behavior. Gas discharge between electrodes influences the adjustments required for interelectrode voltage. The experimental results show： ion intensity increases exponentially with the increment of voltage between drift electrodes; ion intensity decreases exponentially as pressure increases; with the increment of pressure, the breakdown voltage at first decreases, and then increases; ion injection has a significant influence on breakdown voltage, and this influence depends on the pressure and shapes of the electrodes. We explain the results above through assumptions and by mathematical methods.

关键词： drift tube breakdown voltage ion behavior

Investigation on Voltammetric Behavior of Camptothecin and Its analytical Application

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Chinese Journal of Chemistry 2006年第4期24卷 551-556页

作者：郑建斌孟祖超刘波张宏芳 Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry Institute of Analytical Science Northwest University Xi'an Shaanxi 710069 China

The voltammetric behavior of camptothecin （CPT） in Britton-Robinson （B-R） buffer solutions （pH 2.09-9.07） was studied by the means of linear sweep voltammetry （LSV）, cyclic voltarnmetry （CV） and normal pulse voltammetry （NPV） at a hanging mercury drop electrode. In different pH range of B-R buffer solutions, CPT could cause three reduction waves. In B-R buffer solutions （pH 2.09-5.46）, wave P1 yielded by CPT was a two-electron wave. Between pH 6.01 and 9.07, CPT could yield two reduction waves P2 and P3. In addition, the pure CPT obtained from camptotheca acumina grown only in China was determined by NPV, and a linear response was observed in the range of 2.0 × 10^-3-4.0 × 10^-2 mmol·L^-1 with a 0.9991 correlation coefficient and a 8.0 × 1^-4 mmol·L^-1 detection limit for CPT.

关键词： camptothecin drug analysis catalytic hydrogen wave mercury electrode voltammetry

Preliminary studies on the stability of arsenolipids:Implications for sample handling and analysis

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Journal of Environmental Sciences 2016年第11期28卷 97-103页

作者： Muslim Khan Kevin A.Francesconi Institute of Chemistry-analytical Chemistry University of Graz

Human health risk assessments concerning arsenic are now estimating exposure through food in addition to exposure through drinking water. Intrinsic to this assessment is sample handling and preparation that maintains the arsenic species in the form that they occur in foods. We investigated the stability of three arsenolipids（two arsenic fatty acids, As FA-362 and As FA-388, and one arsenic hydrocarbon As HC-332）, common constituents of fish and algae, relevant to sample storage and transport, and to their preparation for quantitative measurements. The fate of the arsenolipids was followed by high performance liquid chromatography/electrospray triple quadruple mass spectrometry（HPLC/ESIMS） *** of the compounds dry as pure compounds or mixed in fish oil at up to 60？C did not result in significant changes to the compounds, although losses were observed by apparent adsorption onto the plastic walls of the polypropylene tubes. No losses occurred when the experiment was repeated with glass tubes. When the compounds were stored in ethanol for up to 15 days under acidic, neutral, or alkaline conditions（each at room temperature）, no significant decomposition was observed, although esterification of the fatty acids occurred at low p H. The compounds were also stable during a sample preparation step involving passage through a small silica column. The results indicate that these typical arsenolipids are stable when stored in glass at temperatures up to 60？C for at least 2 days, and that,consequently, samples of food or extracts thereof can be transported dry at ambient temperatures, i.e. without the need for cool conditions.

关键词： Arsenolipids Stability Mass spectrometry

Structure, photocatalytic and antibacterial activity study of Meso porous Ni and S co-doped TiO2 nano material under visible light irradiation

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Chinese Journal of Chemical Engineering 2019年第7期27卷 1630-1641页

作者： K.V.Divya Lakshmi T.Siva Rao J.Swathi Padmaja I.Manga Raju M.Ravi Kumar Department of Inorganic and analytical Chemistry Andhra University

Undoped and Ni–S co-doped mesoporous TiO2 nano materials were synthesized by using sol–gel *** characteristic features of as prepared catalyst samples were investigated using various advanced spectroscopic and analytical *** characterization results of the samples revealed that all the samples exhibited anatase phase(XRD),decreasing band gap(2.68 eV)(UV–Vis-DRS),small particle size(9.2 nm)(TEM),high surface area(142.156 m^2·g^-1)(BET),particles with spherical shape and smooth morphology(SEM);there is a frequency shift observed for co-doped sample(FT-IR)and the elemental composition electronic states and position of the doped elements(Ni and S)in the TiO2 lattice analyzed by XPS and *** results supported the photocatalytic degradation of Bismarck Brown Red(BBR)achieved with in 110 min and also exhibited the antibacterial activity on Staphylococcus aureus(MTCC-3160),Pseudomonas fluorescence(MTCC-1688)under visible light irradiation.

关键词： Sol–gel Ni–S co-doped TiO2 Photocatalysis under visible light Degradation of Bismarck Brown Red Antibacterial activity

Determination of paraquat in water samples using a sensitive fluorescent probe titration method

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Journal of Environmental Sciences 2013年第6期25卷 1245-1251页

作者： Feihu Yao Hailong Liu Guangquan Wang Liming Du Xiaofen Yin Yunlong Fu analytical and Testing Center Shanxi Normal University

Paraquat （PQ）, a nonselective herbicide, is non-fluorescent in aqueous solutions. Thus, its determination through direct fluorescent methods is not feasible. The supramolecular inclusion interaction of PQ with cucurbit[7]uril was studied by a fluorescent probe titration method. Significant quenching of the fluorescence intensity of the cucurbit[7]uril-coptisine fluorescent probe was observed with the addition of PQ. A new fluorescent probe titration method with high selectivity and sensitivity at the ng/mL level was developed to determine PQ in aqueous solutions with good precision and accuracy based on the significant quenching of the supramolecular complex fluorescence intensity. The proposed method was successfully used in the determination of PQ in lake water, tap water, well water, and ditch water in an agricultural area, with recoveries of 96.73% to 105.77%. The fluorescence quenching values （AF） showed a good linear relationship with PQ concentrations from 1.0 × 10^-8 to 1.2× 10^-5 mol/L with a detection limit of 3.35 x 10-9 mol/L. In addition, the interaction models of the supramolecular complexes formed between the host and the guest were established using theoretical calculations. The interaction mechanism between the cucurbit[7]uril and PQ was confirmed by 1H NMR spectroscopy.

关键词： paraquat coptisine cucurbituril supramolecular interaction fluorescent probe titration

Use of Sewage Sludge After Liming as Fertilizer for Maize Growth

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Pedosphere 2008年第2期18卷 203-213页

作者： M.K.JAMALI T.G.KAZI M.B.ARAIN H.I.AFRIDI A.R.MEMON N.JALBANI A.SHAH National Centre of Excellence in analytical Chemistry

The use of sewage sludge on agricultural land provides an alternative for its disposal. Therefore, the aim of the present study was to evaluate the feasibility of using industrial sewage sludge produced in Pakistan, as an agricultural fertilizer. The agricultural soil amended with 250 g kg^-1 sewage sludge with or without lime treatment was used for the growth of the common local grain crop, maize （Zea maize）. The mobility of the trace and toxic metals in the sludge samples was assessed by applying a modified BCR sequential extraction procedure. The single extraction procedure was comprised of the application of a mild extractant （CaCl2） and water, for the estimation of the proportion of easily soluble metal fractions. To check the precision of the analytical results, the concentrations of trace and toxic metals in every step of the sequential extraction procedure were summed up and compared with total metal concentrations. The plant-available metal contents, as indicated by the deionized water and 0.01 mol L^-1 CaCl2 solution extraction fractions and the exchangeable fraction of the sequential extraction, decreased significantly （P 〈 0.05） with lime application because of the reduced metal availability at a higher pH, except in the cases of Cd and Cu, whose mobility was slightly increased. Sludge amendment enhanced the dry weight yield of maize and the increase was more obvious for the soil with lime treatment. Liming the sewage sludge reduced the trace and toxic metal contents in the grain tissues, except Cu and Cd, which were below the permissible limits of these metals. The present experiment demonstrates that liming was an important factor in facilitating the growth of maize in sludge-amended soil.

关键词： lime treatment maize metals sequential extraction sewage sludge