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Chinese Science Bulletin 2001年第15期46卷 1281-1285页

作者： HE Meiyu XU Jiaxi HE Xiaoran Tak Wah Dominic Chan Rebecca L.C.Lau Department of Chemistry Peking UniversityBeijing 100871China Beijing mass spectrometry Center Beijing 100080China Department of Chemistry The Chinese University of Hong KongShatinN.T.Hong KongChina

The mass spectra of five peptides with biological activities are reported. All mass spectra were recorded using a 4.7-T Fourier transform ion cyclotron resonance mass spectrometer equipped with an external electrospray source. The accurate molecular weights for the five peptides prepared by solid phase synthesis were measured as 1765.9013, 1063.5420, 1092.5254, 820.3804 and 1078.5193, respectively. All the data were obtained with the external calibration. Differences between observed and theoretical monoisotopic molecular weights were in the (0.2-1.0)×10-6 range. The complete primary sequence for the five polypep-tides were determined using the method of in-source electrospray ionization/collision induced dissociation (ESI/CID). All the intact y series ions and b series ions were obtained from various peptides respectively, thus determining the sequences of the five polypeptides. We found that the meas-ured accurate molecular mass of sample 4 was not in agreement with that expected from the planned

关键词： sequence peptide with biological activity Fourier transform ion cyclotron resonance mass spectrometry electrospray collision-induced dissociation.

Study on the Degradation of the Highly Reactive Hypervalent Trifluoromethylation Iodine Reagent PhI（OAc）（CF3）

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Chinese Journal of Chemistry 2015年第12期33卷 1365-1370页

作者： Hui Zhu Shusheng Zhang HaoyangWang Bin Xu Yinlong Guo Department of Chemistry Innovative Drug Research Center Shanghai University Shanghai 200444 China National Center for Organic mass spectrometry in Shanghai State Key Laboratory of Organmetallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Degradation of the highly reactive hypervalent trifluoromethylation iodine reagent PhI（OAc）（CF3）, which can only be generated in situ with mixing PhI（OAc）2 and TMSCF3 in the presence of CsF, was studied by ESI-MS and GC-MS combined with ~9F-NMR. The important transient intermediate PhlCF3＋ was determined by ESI-MS, and the major volatile products containing CF3 were identified with the authentic compounds by using GC-MS, such as trifluoromethylbenzene, 2-iodobenzotrifluoride, 3-iodobenzotrifluoride, 4-iodobenzotrifluoride. Meanwhile, more evidences obtained with 19F-NMR were given for such degradation reaction. A possible rapid CF3 radical transfer reaction pathway was proposed to clarify such degradation progress based on the experimental results. Therefore, this study may be helpful in elucidating the intrinsic reactivity of PhI（OAc）（CF3） and the possible competing side reactions caused by such self-degradation pathway.

关键词： degradation trifluoromethylation iodine reagent mass spectrometry 19F-NMR CF3 radical reaction

Aerosol particles, tobacco smoke, crude oil, coffee roasting and industrial processes: Analysis of complex materials, thermal processes and aerosols by Photo-Ionisation mass spectrometry(PIMS)

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Aerosol particles, tobacco smoke, crude oil, coffee roasting...

2018年中国质谱学术大会（CMSC2018）

作者： R.Zimmermann S.Ehlert J.Heide M.R.Saraji-Bozorgzad A.Walte T.Streibel C.Grimmer H.Czech X.Li L.Li Z.Zhou J.Schade R.Irsig J.Passig Joint mass spectrometry Center of Helmholtz Zentrum München and University of Rostock Institute of mass spectrometry and Atmospheric Environment Jinan University

mass spectrometry with soft Photo-Ionisation(PIMS)1 enables the direct detection of trace molecules in complex organic vapours as well as in pyrolysis or combustion off-gases. This renders PIMS to a well suited tool for Evolved Gas Analysis(EGA) in Thermal Analysis(TA), for detection of the molecular organic signatures of desorption, pyrolysis and combustion processes as well as for applied and fundamental combustion research. In the lecture a brief explanation of the principles of the used photo-ionisation mass spectrometry approaches is given(multi-and single-photon ionisation). In the following the hyphenations of TA-devices to PIMS analysers are presented(e.g. thermogravimetry-PIMS) and applications such as crude oil-analysis are discussed. PIMS also allow the direct monitoring of combustion and pyrolysis processes, e.g. for industrial process monitoring purposes or more fundamental combustion studies. For example the formation of flavour compounds during the coffee roasting process or the formation of toxic compounds form wood combustion or cigarette smoking can be addressed. In summary the potential of soft photo-ionisation mass spectrometry for applied industrial-as well as fundamental-research is demonstrated and discussed. In a second part, the application of photo ionization mass spectrometry for on-line detection of the composition of individual aerosol particles is addressed. The so called aerosol time-of flight mass spectrometry(ATOF) or single particle mass spectrometry(SPAMS) approach uses laser desorption/ionization to generate negative and positive ions(elemental cations, complex cations and anions), mainly from the inorganic bulk of individual airborne aerosol particles of 0.2-20 μm diameter. A SPAMS system of HEXIN Inc. has been equipped with a Photonion GmbH excimer laser and was applied to detect trace emissions of ships using residual fuel using V as tracer. A new development enables the SPAMS approach to detect both, inorganic toxic compounds,

关键词： photo ionization mass spectrometry on-line monitoring of gases and aerosol particles

Trace elements and stable sulfur isotopes in plants of acid mine drainage area:Implications for revegetation of degraded land

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Journal of Environmental Sciences 2020年第8期32卷 128-136页

作者： Agnieszka Gałuszka Zdzisław MMigaszewski Andrzej Pelc Andrzej Trembaczowski Sabina Doł˛egowska Artur Michalik Geochemistry and the Environment Division Institute of ChemistryJan Kochanowski University7 Uniwersytecka St.25-406 KielcePoland mass spectrometry Laboratory Institute of PhysicsMaria Curie-Skłodowska University1 Maria Curie-Skłodowska Sq.20-031 LublinPoland

The abundances of trace elements,a low pH of water and soil in areas impacted by the acid mine drainage(AMD)may cause an excessive uptake of potentially toxic elements and nutritional imbalances in ***-tolerant,native plants are used for revegetation of degraded mining *** established levels of selected trace elements and stable sulfur isotopes in the above-ground plant biomass collected in a mining area in south-central *** 2016,20 samples of the most common species were collected from sites with a different influence of acid mine drainage and analyzed for trace elements by the inductively coupled plasma mass spectrometry *** the basis of the results obtained in 2016,the most contaminated site was selected for a more detailed study,in which sulfur contents and stable sulfur isotope ratios were determined together with trace elements in 17 *** results confirmed that the plants native to the AMD area efficiently accumulated trace elements,especially As and rare earth *** showed the highest content of trace elements,but exhibited the lowest concentrations of sulfur accompanied by the highestδ34S *** has been shown for the first time that stable sulfur isotope composition of AMD plants in south-central Poland is significantly depleted in the 34S isotope showing an averageδ34 S value of–10.5‰in comparison with positiveδ34S values in local vegetation growing outside the AMD area and in local precipitation.

关键词： Trace elements Stable sulfur isotopes Pyrite oxidation Rare earth elements Plants

Glycopeptide ligation via direct aminolysis of selenoester

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Chinese Chemical Letters 2018年第7期29卷 1127-1130页

作者： Jing-Jing Du Ling-Ming Xin Ze Lei Shi-Yao Zou Wen-Bo Xu Chang-Wei Wang Lian Zhang Xiao-Fei Gao Jun Guo Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Hubei International Scientific and Technological Cooperation Base of Pesticide and Green SynthesisCollege of ChemistryCentral China Normal University Jiangxi Key Laboratory for mass spectrometry and Instrumentation East China University of Technology

Direct aminolysis of selenoester in aqueous media was investigated as a glycopeptide ligation *** strategy allows the peptide and glycopeptide ligation to proceed smoothly(even with hindered amino acids) without the need of cysteine residue, N-terminal thiol auxiliary or coupling additive, and to afford the corresponding amide products in excellent yields. No epimerization was observed during ligation reations. In this work, the selenoester of unprotected glycopeptide was readily prepared, and the direct aminolysis of glycopeptide selenoester was successfully applied to synthesize MUC1 mucin sequence efficiently.

关键词： Glycolpeptide Aminolysis Selenoester Additive-free MUC1 mucin

Separation of Intact Monoclonal Antibody Sialylation Isoforms by pH Gradient Ion Exchange Chromatography

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Separation of Intact Monoclonal Antibody Sialylation Isoform...

第十届全国生物医药色谱及相关技术学术交流会

作者： Dai Zhenyu Xu Qun Lina Liang Jeffrey Rohrer Chromatography and mass spectrometry Division Thermo Fisher Scientific

Glycosylated proteins,including erythropoietins,monoclonal antibodies,various hormones,constitute major approved therapeutic biological *** acid is important to cell recognition and migration and critical to circulation half life of the protein as exampled by therapeutic protein rh *** monitoring protein glycosylation,including sialylation,is important for both glycoprotein characterization and quality control *** oligosaccharide profiling（both fluorescently labeled and unlabeled）requires releasing the glycan from the protein and thus is time and labor *** electrophoresis,currently available technique for intact protein sialylation profiling,may not provide enough *** an analysis method with both convenience and higher resolution is needed for protein sialylation monitoring.

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Bouquet-like uranium-containing selenotungstate consisting of two different Keggin-/Anderson-type units with excellent photoluminescence quantum yield

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Chinese Chemical Letters 2023年第1期34卷 198-202页

作者： Mengyuan Cheng Haiying Wang Yufeng Liu Jingwen Shi Mingqi Zhou Weixin Du Dongdi Zhang Guoping Yang Henan Key Laboratory of Polyoxometalate Chemistry College of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China Jiangxi Province Key Laboratory of Synthetic Chemistry Jiangxi Key Laboratory for Mass Spectrometry and InstrumentationEast China University of TechnologyNanchang 330013China

We present the synthesis,characterization and photoluminescence properties of uranium-containing selenotungstate,[(UO_(2))_(3)(SeO_(3))_(3)Na_(5)(H_(2)O)_(6)(SeW_(6)O_(21))(SeW_(9)O_(33))_(3)]^(21–),which was isolated by a one-pot reaction of uranium nitrate with sodium tungstate and sodium selenite in a pH 5.2 aqueous solution at 90°*** this study,the effect of the introduction of lone-electron pair containing heteroatoms on the structure is demonstrated,a three-layered heterometallic{Se_(3)U_(3)Na_(5)}cluster is encapsulated by two different anionic building block units:three trivacant Keggin{B-α-Se W_(9)O_(33)}and one Anderson{SeW_(6)O_(21)}.To our knowledge,the{Se_(3)U_(3)Na_(5)}cluster has never been observed in the polyoxometalate *** solidstate photoluminescence properties and lifetime decay behaviours of the title compound(1)have been measured at room temperature,and the photoluminescence spectrum displays the characteristic emission bands of corresponding uranyl *** addition,the photoluminescence quantum yield of 1 is 72%,which is almost three times that of starting material UO_(2)(NO_(3))_(2)·6H_(2)O(27%).By using this strategy,we envision that an increasing number of assemblies with‘open’clusters may be designed and obtained,in which the exposed oxygen atoms show strong affinity towards metal ions,providing new opportunities to generate bigger clusters or to tune existing properties.

关键词： Polyoxometalates Selenotungstates Uranium Synthesis Photoluminescence

H_(4)SiW_(12)O_(40)-catalyzed cyclization of epoxides/aldehydes and sulfonyl hydrazides: An efficient synthesis of 3,4-disubstituted 1H-pyrazoles

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Chinese Chemical Letters 2022年第3期33卷 1483-1487页

作者： Guoping Yang Xuanjie Xie Mengyuan Cheng Xiaofei Gao Xiaoling Lin Ke Li Yuanyuan Cheng Yufeng Liu Jiangxi Key Laboratory for mass spectrometry and Instrumentation Jiangxi Province Key Laboratory of Synthetic ChemistryEast China University of TechnologyNanchang 330013China Henan Key Laboratory of Polyoxometalate Chemistry College of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China

A simple and efficient method for the synthesis of pyrazoles through a silicotungstic acid (H_(4)SiW_(12)O_(40))-catalyzed cyclization of epoxides/aldehydes and sulfonyl hydrazides has been developed. Various epoxides/aldehydes were smoothly reacted with sulfonyl hydrazides to furnish regioselectivity 3,4-disubstituted 1H-pyrazoles. The application of such an earth-abundant, readily accessible, and nontoxic catalyst provides a green approach for the construction of 3,4-disubstituted 1H-pyrazoles. A plausible reaction mechanism has been proposed on the basis of control experiments, GC-MS and DFT calculations.

关键词： Silicotungstic acid Epoxides Aldehydes Sulfonyl hydrazides 3,4-Disubstituted 1H-pyrazoles

Determination of Carbendazim in Orange Juice by On-line SPE- HPLC

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Determination of Carbendazim in Orange Juice by On-line SPE-...

第十届全国生物医药色谱及相关技术学术交流会

作者： Huang Xiongfeng Xu Qun Liang Lina Jeffrey Rohrer Chromatography and mass spectrometry Division Thermo Fisher Scientific

＜正＞Carbendazim is a fungicide used in many countries to improve crop production;however,its slow degradation rate and high toxicity may be damaging to human *** regulates the maximum residue limit of carbendazim in foods at 0.5 mg/*** the U.S.,the Environmental Protection Agency has not approved carbendazim for use as a fungicide on oranges,nor has it

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Determination of p-Toluenesulfonic Acid in Water-Insoluble Drugs by Ion Chromatography

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Determination of p-Toluenesulfonic Acid in Water-Insoluble D...

第十届全国生物医药色谱及相关技术学术交流会

作者： Liao Dongli Pan Guangwen Xu Qun Liang Lina Jeffrey Rohrer Chromatography and mass spectrometry Division Thermo Fisher Scientific

＜正＞p-Toluenesulfonic acid is an organic acid,and widely used in pharmaceutical industry as counter-ions for basic drugs because of its strong acidic and hydrophilic ***,it is important to determine the content of p...

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