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The effect of cation size(H^+, Li^+, Na^+, and K^+) on McLafferty-type rearrangement of even-electron ions in mass spectrometry

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Science China Chemistry 2014年第5期57卷 662-668页

作者： CHAI YunFeng pan yuanjiang Department of Chemistry Zhejiang University

Protonation and alkali-metal cation adduction are the most important ionization processes in soft-ionization mass *** on the fragmentation mechanism of protonated and alkali-metal-cationized compounds in tandem mass spectrometry are essential and helpful for structural *** some cases,it was often observed that a compound attached by different alkali-metal cations(or proton)exhibits similar fragmentation patterns but the relative abundances of product ions are *** difference was considered to derive from the different electrostatic interactions of alkali-metal cations(or the bonded effect of proton)with the *** alkali-metal cation with a smaller ionic radius shows stronger electrostatic interaction with the molecule because of its higher charge *** addition,the bonded effect of the proton is stronger than the electrostatic interaction of the alkali-metal *** the present study,which used McLafferty-type rearrangements of even-electron ions([M+Cat]+,Cat=H,Li,Na,K)as model reactions,the effect of cation size in mass spectrometric fragmentation reactions is *** considerations were also successfully applied to interpret the similar but distinct fragmentation behavior of proton and alkali-metal cation adducts of a synthetic compound(2-(acetamido(phenyl)methyl)-3-oxobutanoate)and a drug(entecavir).

关键词： even-electron ion alkali-metal cation McLafferty rearrangement charge-remote fragmentation ionic radius

澳洲坚果壳活性炭载锌复合抗菌材料的制备及性能研究

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西南林业大学学报（自然科学） 2024年第1期44卷 166-175页

作者：张建珠杨正芳潘源江张彬聂艳丽普洱市林业和草原科学研究所云南普洱665000 昆明理工大学理学院云南昆明650500 云南省林业和草原技术推广总站云南昆明650224

以澳洲坚果壳为原料,采用氯化锌活化法制备粉末活性炭作为抗菌材料载体,通过浸渍法将Zn^(2+)负载于活性炭的表面和微孔中,得到活性炭载锌复合抗菌材料。利用碘吸附值、氮气吸脱附、扫描电子显微镜、电感耦合等离子体-发射光谱及抗菌实... 详细信息

以澳洲坚果壳为原料,采用氯化锌活化法制备粉末活性炭作为抗菌材料载体,通过浸渍法将Zn^(2+)负载于活性炭的表面和微孔中,得到活性炭载锌复合抗菌材料。利用碘吸附值、氮气吸脱附、扫描电子显微镜、电感耦合等离子体-发射光谱及抗菌实验对材料进行表征。结果表明:活性炭材料具有多孔结构,比表面积达644.118 m^(2)/g,平均孔径为2.289 nm,碘吸附值为1018 mg/g。以硫酸锌为锌源,炭锌接触时间7 h、炭锌浸渍比1∶25、锌溶液浓度1.0 mol/L时,制备的活性炭载锌复合抗菌材料具有较好的杀菌性能,对大肠杆菌和金黄色葡萄球菌都能达到99.9%的抗菌率。活性炭载锌复合抗菌材料与织物浸渍得到的抗菌织物也具有较好的抗菌效果,展现了良好的应用前景。本研究可为拓宽废弃生物质资源的应用范围提供参考。

关键词：澳洲坚果果壳活性炭 Zn^(2+) 抗菌性能抗菌材料

电催化5-羟甲基糠醛氧化为2,5-呋喃二甲酸的研究进展

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能源环境保护 2024年第2期38卷 81-93页

作者：潘远江郭珍燕黄金术李虎贵州大学绿色农药全国重点实验室教育部绿色农药与农业生物工程重点实验室生物质资源综合利用国家地方联合工程实验室精细化工研究开发中心贵州贵阳550025

在可持续发展导向下,替代能源需求不断增加,生物质资源的有效利用成为研究焦点。5-羟甲基糠醛(HMF)作为一种生物质基平台化合物,具有广阔的应用前景。通过选择性氧化反应,HMF可以转化为高附加值化合物,如2,5-呋喃二甲酸(FDCA)。近年来,... 详细信息

在可持续发展导向下,替代能源需求不断增加,生物质资源的有效利用成为研究焦点。5-羟甲基糠醛(HMF)作为一种生物质基平台化合物,具有广阔的应用前景。通过选择性氧化反应,HMF可以转化为高附加值化合物,如2,5-呋喃二甲酸(FDCA)。近年来,电催化氧化作为一种绿色环保的新型手段,在HMF转化为FDCA的研究中取得了显著进展。然而,这一过程涉及竞争反应,如水氧化,对FDCA的产率和法拉第效率产生影响。催化剂对降低反应能垒、提高产物选择性至关重要,但面临稳定性不足、过电位偏高和酸性环境下活性不足等挑战。聚焦于高效催化剂的研究进展,从贵金属催化剂到非贵金属催化剂和非金属催化剂进行深入探讨,旨在为生物质的高效转化提供有益参考。

关键词：电化学氧化生物质 5-羟甲基糠醛 2,5-呋喃二甲酸电催化剂

Fragmentation mechanism of product ions from protonated proline-containing tripeptides in electrospray ionization mass spectrometry

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Chinese Science Bulletin 2012年第17期57卷 2051-2061页

作者： YOU ZhuShuang WEN YongJun JIANG KeZhi pan yuanjiang Department of Chemistry Zhejiang UniversityHangzhou 310027China Chengdu Capgemini Biomedical Technology Company Ltd.Chengdu 611330China Key Laboratory of Organosilicon Chemistry and Material Technology Hangzhou Normal UniversityHangzhou 310012China

The dissociation chemistry of primary fragment ions from the protonated proline-containing tripeptides glycylprolylglycine,prolylglycylglycine,and prolylprolylglycine was investigated by electrospray ionization multi-stage mass ***-tions showed the a 2 ions generated from b 2 ions were cyclic,which is energetically more favorable than the linear *** prolyl residue in the structure affected the energy hypersurface of the dissociation reaction from the b 2 ion to the a 2 *** the fragmen-tation of a 2 ions,the iminium-imine complex corresponding to loss of CO from the a 2 ion was suggested to be an ion-neutral com-plex (INC).The a 1 ion was generated from direct separation of this INC,and the internal iminium ion,which was absent in PGG,was generated from another INC that was formed from the first INC via proton-bridged complex-mediated intramolecular proton *** these intermediates are unstable,their existence is supported by experiments and density functional theory calculations.

关键词：分子内质子转移质谱裂解机理碎片离子电喷雾脯氨酸三肽产品密度泛函理论

Analysis of the binding sites with NL-101 to amino acids and peptides by HPLC/MS/MS

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Chinese Chemical Letters 2019年第1期30卷 103-106页

作者： Lingzi Dai Nian Guo Yaqin Liu Shanshan Shen Qiufu Ge yuanjiang pan Department of Chemistry Zhejiang University Hangzhou Pharmaceutical Group Co. Ltd.

The binding between NL-101, a novel nitrogen mustard anti-cancer drug, with amino acids and peptides has been investigated by high performance liquid chromatography electrospray tandem mass spectrometry(HPLC/ESI-MS/MS). This study offers supporting data of the interaction among drug and amino acids and peptides, which could potentially explain the cytotoxic and mutagenic effects of the drug. Collision-induced dissociation(CID) experiment demonstrated that under the same collision energy, the amino group combined with NL-101 adducts are sensitive and often produce more fragment ions; the carboxyl group combined with NL-101 adducts are hard to break and display fewer fragment ions. In addition, when other group(like sulfhydryl group) of amino acids binds to NL-101, CID spectra show different fragmentation pattern. These differences could display structural information about the drug adducts and be utilized as location of the authentic binding sites.

关键词： High-performance liquid chromatography/ tandem mass spectrometry NL-101 Amino acids Peptides Binding sites

Intrinsic effects of precursor functional groups on the Na storage performance in carbon anodes

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Nano Research 2023年第11期16卷 12579-12586页

作者： Xiaohan Tang Fei Xie Yaxiang Lu Zhao Chen Xiangfei Li Hong Li Xuejie Huang Liquan Chen yuanjiang pan Yong-Sheng Hu Department of Chemistry Zhejiang UniversityHangzhou 310027China Key Laboratory for Renewable Energy Beijing Key Laboratory for New Energy Materials and DevicesBeijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190China Huairou Division Institute of PhysicsChinese Academy of SciencesBeijing 101400China Yangtze River Delta Physics Research Center Co. Ltd.Liyang 213300China College of Materials Science and Optoelectronic Technology University of Chinese Academy of SciencesBeijing 100049China

The oxygen-containing functional groups in disordered carbon anodes have been widely reported to influence the Na storage ***,the effect of original oxygen-containing groups in the precursors on the final structures and electrochemical performance is rarely ***,we used the anthraquinone derivatives with different oxygen-containing functional groups as precursors to make the disordered carbon anodes for Na-ion batteries(NIBs).Through comprehensive structural and electrochemical analyses,we found that the different types of functional groups in carbon precursors directly affect the cross-linking process during *** original precursors containing enough inter-chain oxygen or oxygen-containing functional groups with unsaturated bonds unattached to the ring are beneficial for the oxygen atoms to remain or cross-link in structure to result in more C–O–C group,forming nanovoids and disordered structure,which then determine the high performance of the carbon anodes in *** work highlights the importance of the type/content of functional groups in precursor and provides guidance for the future design of carbon anodes in NIBs from the perspective of precursor selection.

关键词： disordered carbon precursor oxygen-contained functional group Na-ion batteries

Applications of ambient electric arc ionization mass spectrometry in saline samples

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Chinese Chemical Letters 2022年第5期33卷 2708-2710页

作者： Yuan Li Yuanji Gao Binpeng Zhan Weiwei Chen Fengjian Chu Hongru Feng Zhan Gao Zihan Ma yuanjiang pan Department of Chemistry Zhejiang UniversityHangzhou 310027China College of Chemistry and Materials Science Sichuan Normal UniversityChengdu 610068China

Salinity tolerance of ambient electric arc ionization(AEAI)was evaluated by comparing electrospray ionization for various samples at NaCl concentrations from 0 to 1000 mmol/***-mass spectrometry(AEAI-MS)exhibited an excellent signal intensity even at NaCl concentrations of 1000 mmol/L,while the ESI-MS had no signal because high salinity has a strong inhibitory effect on *** sodium adduct was verified using LiCl instead of ***-MS successfully quantified saline samples with an excellent quantitative ability(R^(2)≥0.998).We also achieved some analytical samples in the buffer solution at a very high concentration and even in a saturated salt ***,AEAI-MS has protonated ions for most target *** addition,the relationship between auxiliary temperature and the distance from the sample to the arc was investigated,and the results indicated that thermal desorption plays an important role in AEAI source.

关键词： Electric arc Ion source Salinity tolerance Mass spectrometry Ambient electric arc ionization

Comparison of the clinical features and therapeutics of COVID-19 in cardio-cerebrovascular disease(CCVD)and non-CCVD patients

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Frontiers of Medicine 2021年第4期15卷 629-637页

作者： Yu Wang Lan Li yuanjiang pan Yu He Zuhua Chen Yunhao Xun Yuhan Xu Yilei Guo Jiehong Yang Jianchun Guo Haitong Wan Institute of Cardio-cerebrovascular Disease Zhejiang Chinese Medical UniversityHangzhou 310053China Department of Chemistry Zhejiang UniversityHangzhou 310027China College of Pharmaceutical Science Zhejiang Chinese Medical UniversityHangzhou 310053China School of Basic Medical Sciences and Public Health Zhejiang Chinese Medical UniversityHangzhou 310053China Integrated TCM&Western Medicine Department Xixi Hospital of HangzhouHangzhou 310023China

Cardio-cerebrovascular disease(CCVD)is a major comorbidity of coronavirus disease 2019(COVID-19).However,the clinical characteristics and outcomes remain *** this study,102 cases of COVID-19 from January 22,2020 to March 26,2020 in Xixi Hospital of Hangzhou were *** cases had pre-existing *** showed that compared with non-CCVD patients,those with CCVD are more likely to develop severe disease(15%versus 1%),and the proportion of pneumonia severity index grade IV was significantly higher(25%versus 3.6%).Computed tomography images demonstrated that the proportion of multiple lobe lesion involvement was significantly higher in the CCVD group than in the non-CCVD group(90%versus 63.4%).Compared with non-CCVD group,the levels of C-reactive protein,fibrinogen,D-dimer,and serum amyloid-A were higher,whereas the total protein and arterial partial Pa02 were lower in the CCVD *** no statistical difference was observed in the outcomes between groups,CCVD patients received more intensive comprehensive treatment to improve COVID-19 symptoms compared with non-CCVD *** Chinese and Western medicine treatments have certain advantages in controlling the severe conversion rate and mortality of *** addition,given that COVID-19 patients are usually related to coagulation disorders and thrombosis risk,the application of Chinese medicine in promoting blood circulation and removing stasis should be strengthened.

关键词： COVID-19 cardio-cerebrovascular disease traditional Chinese medicine clinical features clinical therapeutics

Tip-assisted ambient electric arc ionization mass spectrometry for rapid detection of trace organophosphorus pesticides in strawberry

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Chinese Chemical Letters 2022年第9期33卷 4411-4414页

作者： Zihan Ma Yuanji Gao Fengjian Chu Yunli Tong Yuwen He Yuan Li Zhan Gao Weiwei Chen Shuheng Zhang yuanjiang pan Department of Chemistry Zhejiang UniversityHangzhou 310027China College of Chemistry and Materials Science Sichuan Normal UniversityChengdu 610068China College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027China Zhejiang East Asia Pharmaceutical Co. Ltd.Taizhou 317108China

In this study,an ambient mass spectrometry(AMS)based method was developed for rapid detection of organophosphorus pesticides in *** method combines an electric arc and a microsyringe tip to realize tip-assisted ambient electric arc ionization(TAAEAI).A high-voltage electric arc can be applied to the microsyringe tip to generate an electric field,which results in corona discharge at the microsyringe *** juiced strawberry sample loaded on the tip could be directly ionized with TAAEAI and then analyzed by a mass ***-MS was successfully applied to analyze 6 organophosphorus pesticides in three strawberry *** and profenofos were detected from the investigated strawberry *** method could quantitatively determine the contents of organophosphorus pesticides in strawberry with high reproducibility,high precision,and high *** matrices did not interfere with the pesticide *** recoveries of organophosphorus pesticides spiked in strawberry samples varied between 82.6%and 116%with relative standard deviations(RSDs)less than 9.2%.The limits of detection(LODs)varied between 0.0124µg/g and 0.0245µg/g,while the limits of quantification(LOQs)varied between 0.0413µg/g and 0.0817µg/*** coefficients of determination(R2)of the method were determined to be>*** method established here may have potential application in the detection of organophosphorus pesticides in vegetables and fruits.

关键词： Pesticide Ambient mass spectrometry Tip-assisted ambient electric arc ionization Strawberry Matrix interference