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Elemental characterization of black shales of Khyber Pakthunkhawa (KPK) region of Pakistan using AAS

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Chinese Journal Of Geochemistry 2013年第3期32卷 248-251页

作者： Abdul Aziz Muhammad Sajjad Bashir Mohammad central analytical facility division Pakistan Institute of Nuclear Science and Technology Department of Construction Environment Engineering University of Science and Technology

Black shale samples were collected from Chimiari Khyber Pakthunkhawa region of Pakistan and were analyzed for elemental compositions. Atomic Absorption Spectrophotometry (AAS) was utilized for the determination of elements in the digested solutions. The analysis of black shale was performed precisely with relative standard deviation (RSD) lower than 2%. Results showed that the samples contained high concentrations of Ca (11.98 %), Al (7.09%), Fe (3.03%), Mg (0.59%) and Ti (0.58%).

关键词：原子吸收光谱法黑色页岩巴基斯坦元素组成表征相对标准偏差元素测定精确分析

Influence of supports on photocatalytic degradation of phenol and 4-chlorophenol in aqueous suspensions of titanium dioxide

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Journal of Environmental Sciences 2013年第2期25卷 399-404页

作者： Kashif Naeem Feng Ouyang central analytical facility division Pakistan Institute of Nuclear Science and Technology Environmental Science and Engineering Research Center Harbin Institute of Technology Shenzhen Graduate School

The photocatalytic degradation of phenol and 4-chlorophenol （4-CP） in aqueous suspensions with the use of titanium dioxide （TiO2 ） under UV irradiation was examined. The effects of different supporting materials mixed physically with TiO2 were studied to achieve maximum degradation efficiency. Among the three supports, namely activated carbon （AC）, silica （SiO2 ） and zeolite （ZSM-5）, all exhibited paramount efficiency for degradation of phenol and 4-CP and was better than TiO2 alone. The optimum concentration was found to be 50 mg for all supporting materials. The efficiency order of the three supports was as follows： AC 〉 ZSM-5 〉 SiO2 , respectively. Whilst, the degradation of phenol and 4-CP was improved from 70.6% to 87.6% and 80.6% to 89.7%, respectively, within 120 min photocatalysis in the presence of optimal amount of AC. The degradation was also comparatively enhanced in the presence of cheaper rice husk and the activity was closed to ZSM-5 and lower than AC.

关键词： 4-chlorophenol phenol photocatalytic degradation support TiO2

Analysis of isoquinoline alkaloids from Mahonia leschenaultia and Mahonia napaulensis roots using UHPLC-Orbitrap-MSn and UHPLC-QqQ LIT-MS/MS

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Journal of Pharmaceutical Analysis 2017年第2期7卷 77-86页

作者： Awantika Singh Vikas Bajpai Sunil Kumar Ajay Kumar Singh Rawat Brijesh Kumar Sophisticated analytical Instrument facility division CSIR-Central Drug Research InstituteLucknow 226031India Academy of Scientific and Innovative Research New Delhi 110001India Pharmacognosy and Ethnopharmacology division CSIR-National Botanical Research InstituteLucknow 226001India

Mahonia leschenaultia（ML） and Mahonia napaulensis（MN） are less known and unexplored medicinal plants of the family Berberidaceae. They are used by the Todas of Nilgiris in their religious and medical practices but chemically less identified. Hence, we decided to do extensive phytochemical analysis to explore the potential of these plant extracts. An ultrahigh performance electrospray tandem mass spectrometry（UHPLC-ESI-MS/MS）method was successfully developed for qualitative analysis of the bioactive components in Mahonia species using Orbitrap Velos Pro mass spectrometer. Sixteen compounds were identified by comparison of their retention times and mass spectra（MS） with authentic standards and reported literature. Multi-stage mass spectra（MS（2-8）） for the identification of protoberberine and aporphine alkaloids showed the sequential expulsion of all the substituents attached with their basic skeleton followed by CO loss. Eight of the identified compounds（berberine, jatrorrhizine, palmatine, magnoflorine, isocorydine, glaucine, tetrahydropalmatine and tetrahydroberberine） were simultaneously determined by another UHPLC-ESI-MS/MS method under the multiple reactions monitoring（MRM） mode quantitatively using triple quadrupole linear ion trap mass spectrometer. The analytical method was validated for 8 bioactive compounds with overall recovery in the range98.5%-103.6%（RSD≤2.2%）, precise（RSD≤2.07%） and linear（r≥0.9995） over the concentration range of 0.5-1000 ng/mL and successfully applied in ML and MN roots, which suggests the suitability of the proposed approach for the routine analysis of Mahonia species and their quality control.

关键词： Orbitrap-MS QqQLIT-MS Mahonia leschenaultia Mahonia napaulensis Isoquinoline alkaloids

Rapid screening and distribution of bioactive compounds in different parts of Berberis petiolaris using direct analysis in real time mass spectrometry

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Journal of Pharmaceutical Analysis 2015年第5期5卷 332-335页

作者： Awantika Singh Vikas Bajpai Mukesh Srivastava Kamal Ram Arya Brijesh Kumar Sophisticated analytical Instrument facility(SAIF) CSIR-Central Drug Research Institute Academy of Scientific and Innovative Research(AcSIR) Biometric and Statistics division CSIR-Central Drug Research Institute Botany division CSIR-central Drug Research Institute

Berberis petiolaris Wall. ex G. Don, an unexplored medicinal plant belonging to the family Berberidaceae, is a large deciduous shrub found in Western Himalaya between 1800-3000 m. Chemical profiling of fruit, leaf, root and stem was done by direct analysis in real time mass spectrometry followed by multivariate analysis for discrimination among the plant parts. The bioactive compounds, including magnofiorine, berberine, jatrorrhizine, thalifendine/berberrubine, demethyleneberberine, reticuline, 8-oxoberberine, N-methyltetrahydroberberine, tetrahydropalmatine, tetrahydroberberine and palmatine, were identified by their exact mass measurement and the corresponding molecular formula of each compound. A comparative study of distribution pattern for all these bioactive alkaloids showed qualitative and quantitative variations in different parts of B. petiolaris. Principal component analysis clearly dis- criminated each part of B. petiolaris plant.

关键词： Berberis petiolarisAlkaloidsProfilingDART-TOF-MSStatistical analysis

Identification and characterization of phenolics and terpenoids from ethanolic extracts of Phyllanthus species by HPLC-ESI-QTOF-MS/MS

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Journal of Pharmaceutical Analysis 2017年第4期7卷 214-222页

作者： Sunil Kumar Awantika Singh Brijesh Kumar Sophisticated analytical Instrument facility CSIR-Central Drug Research InstituteLucknow 226031Uttar PradeshIndia Academy of Scientific and Innovative Research (AcSIR) New Delhi 110025India

Phyllanthus species plants are a rich source of phenolics and widely used due to their medicinal properties. A liquid chromatography–tandem mass spectrometry(LC–MS/MS) method was developed using high-pressure liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry(HPLC-ESI-QTOFMS/MS) for the identification and characterization of quercetin, kaempferol, ellagic acid and their derivatives in ethanolic extracts of Phyllanthus species. The chromatographic separation was carried out on Thermo Betasil C_8 column(250 mm×4.5 mm, 5 μm) using 0.1% formic acid in water and 0.1% formic acid in methanol as the mobile phase. The identification of diagnostic fragment ions and optimization of collision energies were carried out using 21 reference standards. Totally 51 compounds were identified which include 21 compounds identified and characterized unambiguously by comparison with their authentic standards and the remaining 30 were tentatively identified and characterized in ethanolic extracts of P. emblica, P. fraternus, P. amarus and ***.

关键词： Phyllanthus species HPLC-ESI-QTOF-MS/MS Phenolics

Elemental profile of black shales

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Chinese Journal Of Geochemistry 2011年第2期30卷 217-219页

作者： KASHIF Naeem WASIM Yawar TARIQ M.Bhatti BASHIR Mohammad central analytical facility division Pakistan Institute of Nuclear Science and TechnologyP.O.NiloreIslamabad 45650Pakistan Pakistan Institute of Engineering and Applied Sciences P.O.NiloreIslamabad 45650Pakistan

A black shale sample collected from the Chimiari site(Tarbela) was analyzed for elemental *** coupled plasma-optical emission spectrometry(ICP-OES) was employed to determine major and trace elements in the *** analysis was accomplished for the black shales,which was better than 2.0%.Result shows that the shales are very rich in Ca(25439 μg·g-1),Fe(13933 μg·g-1),Ti(6932 μg·g-1),Al(5993 μg·g-1) and K(2730 μg·g-1).

关键词：黑页岩 ICP-OES 踪迹元素

Modeling of removal of an organophosphorus pesticide from aqueous solution by amagnetic metal–organic framework composite

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Chinese Journal of Chemical Engineering 2021年第12期34卷 323-335页

作者： Abdolraouf Samadi-Maybodi Mohsen Nikou analytical division Faculty of ChemistryUniversity of MazandaranBabolsarIran

Today,a variety of pesticides are used to fight plant pests in the *** entry of these resistant pollutants into water resources can have devastating effects on human health and the environment,hence their removal from the environment is a vital *** the present work,the magnetic iron-based metalorganic framework(Fe_(3) O_(4)/MIL-101(Fe)) was synthesized by a simple and feasible method and characterized by FT-IR,XRD,BET,FESEM,TEM,TGA,and VSM *** synthesized nanocom posite was successfully applied for the removal of fenitrothion(FEN) pesticide from the aqueous *** isothermal and kinetic models were also *** Langmuir isotherm model(type I) and pseudo-second-order kinetic model were more consistent in the adsorption *** thermodynamic parameters of fenitrothion sorption were also *** results revealed that the adsorption of fenitrothion onto Fe_(3) O_(4)/MIL-101(Fe) was spontaneous and endothermic under optimized ***,the removal efficiency of FEN was predicted using the developed fuzzy logic *** input variables including the initial concentration of FEN(mg·L^(-1)),pH of the solution,adsorbent dosage(mg).and contact time(min) versus removal efficiency as output were fuzzified by the usage of an artificial intelligence-based *** fuzzy subsets consisted of Triangular and Trapezoidal membership functions(MFs) with six levels and a total of 23 rules in IF-THEN format which was applied on a Mamdani inference *** obtained coefficient of determination value(R_(pred)^(2)=0.98205) proved the excellent accuracy of the fuzzy logic model as a powerful tool for the prediction of FEN removal efficiency.

关键词： Fenitrothion Magnetic iron-based metal–organic framework Fuzzy logic Adsorption Isotherm Mamdani

Small angle X-ray scattering used in precipitation in AlZnMgCuLi alloy

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中国有色金属学会会刊：英文版 2003年第6期13卷 1301-1305页

作者：杜志伟周铁涛刘培英陈昌麒钟皓洪新国赵辉董宝中 School of Materials Science and Engineering Beijing Synchrotron Radiation facility division

Small angle X-ray scattering has been used to study the variation of microstructure parameters in an Al-Zn-Mg-Cu-Li alloy aged at various temperatures for various durations. Coarsening of precipitates was studied by analyzing the curve of kinetics strength vs the cube of radius. The results show that the coarsening of precipitates conforms to LSW principle. In addition, the characteristic of s^3J(s) vs s curves was analyzed. The results show that the curves for samples aged at 160 ℃ for various durations(24, 48 and 96 h) have negative deviation, which maybe results in the formation of certain new precipitate. In the other aging treatment states, the curves conform to Porod principle which means there is sharp boundary between the precipitates and matrix.

关键词： AIZnMgCuLi合金铝合金析出 XRD 显微结构

Cadmium in soybeans and the relevance to human exposure

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Journal of Environmental Sciences 2015年第11期27卷 157-162页

作者： Ashley M.Newbigging Xiaowen Yan X.Chris Le division of analytical and Environmental Toxicology Department of Laboratory Medicine and Pathology University of Alberta

Introduction Cadmium is considered a human carcinogen by the International Agency for Research on Cancer（IARC,1993）and the US National Toxicology Program（NTP,1997）.Cadmium contamination of food crops is a persistent issue for both the agricultural industry as well as *** is an issue for agriculture because cadmium can be present in soils naturally or as a result of industrial processes and can contaminate foods that are consumed by ***

关键词： Cadmium Metals Food safety Dietary exposure Agricultural products Uptake of cadmium from soil