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  1. Article: Selective production and characterization of aromatic carboxylic acids from Xianfeng lignite-derived residue by mild oxidation in aqueous H2O2 solution

    Liu, Fang-Jing / Juan Gui / Lei Bai / Xiang-Nan Zhu / Xian-Yong Wei / Zhi-Min Zong

    Fuel processing technology. 2018 Dec. 01, v. 181

    2018  

    Abstract: ... oxidation. In this study, valuable aromatic polycarboxylic acids were produced from Xianfeng lignite-derived ...

    Abstract Lignites show great potential as feedstock for the production of valuable carboxylic acids by mild oxidation. In this study, valuable aromatic polycarboxylic acids were produced from Xianfeng lignite-derived residue (XLDR) through mild oxidation in green aqueous H2O2 solution. The results show that XLDR oxidation can produce benzene carboxylic acids (BCAs) and polycyclic aromatic carboxylic acids (PCACAs) in high selectivity. The BCAs are dominated by mellitic acid and benzenepentacarboxylic acid with 55.5% and 13.3% in the total yield of all group components based on the analysis with gas chromatography/mass spectrometer. Moreover, three series of PCACAs with an aliphatic ring were identified by direct analysis in a real-time ionization source coupled to a time-of-flight mass spectrometer. The BCAs and PCACAs could be generated from different kinds of aromatic structures via oxidation by OH produced from H2O2.
    Keywords benzene ; carboxylic acids ; feedstocks ; gas chromatography-mass spectrometry ; hydrogen peroxide ; ionization ; oxidation ; spectrometers
    Language English
    Dates of publication 2018-1201
    Size p. 91-96.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 1483666-x
    ISSN 0378-3820
    ISSN 0378-3820
    DOI 10.1016/j.fuproc.2018.09.006
    Database NAL-Catalogue (AGRICOLA)

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  2. Article: Investigation on compositional and structural features of Xianfeng lignite through sequential thermal dissolution

    Wang, Tie-Min / Chang Liu / Dong-Dong Zhang / Fang-Jing Liu / Jing Liu / Jing-Hui Lv / Juan Gui / Meng Qu / Xiang-Xue Liu / Xian-Yong Wei / Yan Li / Zhe-Hao Wei / Zhi-Min Zong

    Fuel Processing Technology. 2015 Oct., v. 138

    2015  

    Abstract: Xianfeng lignite (XL) was subjected to sequential thermal dissolution (TD) in cyclohexane at 200â ...

    Abstract Xianfeng lignite (XL) was subjected to sequential thermal dissolution (TD) in cyclohexane at 200–320°C. The yields of soluble portions (SPs) decreased with raising temperature from 200 to 260°C, but then increased with further raising the temperature. The SPs were analyzed with a Fourier transform infrared spectrometer, gas chromatograph/mass spectrometer, and atmospheric pressure solid analysis probe/time-of-flight mass spectrometer (ASAP/TOF-MS). The results show that cyclohexane is effective for thermally extracting inherent hydrocarbons in XL without breaking the covalent bonds. Intermolecular interactions such as hydrogen bonds, π–hydrogen bonds, and π–π interactions can be destroyed at higher temperatures and thereby release arenes and arenols trapped in the capsule structure of XL. According to ASAP/TOF-MS analysis, the molecular mass of organic species in the SPs is smaller than 550 u and SPs from different TD temperatures have different molecular mass distributions. The organic species detected with ASAP/TOF-MS have double bond equivalent values ranging from 0 to 11 and carbon numbers from 3 to 35. A series of arenes and alkylarenols were also confirmed by ASAP/TOF-MS analysis.
    Keywords aromatic hydrocarbons ; atmospheric pressure ; carbon ; cyclohexanes ; Fourier transform infrared spectroscopy ; gas chromatography ; hydrogen bonding ; lignite ; molecular weight ; spectrometers ; temperature
    Language English
    Dates of publication 2015-10
    Size p. 125-132.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 1483666-x
    ISSN 0378-3820
    ISSN 0378-3820
    DOI 10.1016/j.fuproc.2015.04.029
    Database NAL-Catalogue (AGRICOLA)

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  3. Article: Characterization of Biomarkers and Structural Features of Condensed Aromatics in Xianfeng Lignite

    Liu, Fang-Jing / Gui Juan / Li Peng / Wang Yu-Gao / Wei Xian-Yong / Zong Zhi-Min

    Energy & Fuels. 2013 Dec. 19, v. 27, no. 12

    2013  

    Abstract: Xianfeng lignite (XL) was sequentially extracted under ultrasonication at room temperature ...

    Abstract Xianfeng lignite (XL) was sequentially extracted under ultrasonication at room temperature with petroleum ether, carbon disulfide (CDS), methanol, acetone, and isometric CDS/acetone mixed solvent to afford extracts 1–5, respectively. The mixed solvent-inextractable portion was sequentially extracted with cyclohexane, benzene, 1-methylnaphthalene, methanol, and ethanol at 320 °C to afford extracts 6–10, respectively. The extracts were analyzed with a gas chromatography/mass spectrometer (GC/MS) to characterize biomarkers in XL. The biomarkers were significantly enriched in extracts 1 and 6. They can be classified into a series of n-alkanes, isoprenoid alkanes, terpenoids, n-alkenes, methyl alkanones, n-alkylbenzenes, n-alkyltoluenes, and n-alkyl-p-xylenes. The biomarker distributions provided important information on the main origin of organic matter in XL. Related mechanisms for the formation of biomarkers during coalification were discussed. The residue from sequential thermal extraction was subjected to ruthenium-ion-catalyzed oxidation along with subsequent product analyses with GC/MS and direct analysis in a real-time ionization source coupled to a time-of-flight mass spectrometer (DARTIS/TOFMS) to understand its structural features. The results show that the residue is rich in condensed aromatics (CAs) and methyl is the dominant alkyl side chain on aromatic rings. The aromatic rings in the residue are mainly connected by −(CH₂)₃– and −CHCH₃(CH₂)₂–. DARTIS/TOFMS analysis suggests that CAs with alkyl-substituted biphenyl and alkyl-substituted phenylbiphenyl skeletons also exist in the residue. This investigation provides an effective approach for understanding biomarkers and the structural features of the macromolecular network in XL.
    Keywords acetone ; alkenes ; ambient temperature ; benzene ; biomarkers ; biphenyl ; carbon disulfide ; cyclohexanes ; ethanol ; ethers ; gas chromatography-mass spectrometry ; ionization ; lignite ; methanol ; organic matter ; oxidation ; petroleum ; solvents ; spectrometers ; terpenoids ; ultrasonic treatment
    Language English
    Dates of publication 2013-1219
    Size p. 7369-7378.
    Publishing place American Chemical Society
    Document type Article
    ZDB-ID 1483539-3
    ISSN 1520-5029 ; 0887-0624
    ISSN (online) 1520-5029
    ISSN 0887-0624
    DOI 10.1021%2Fef402027g
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  4. Article: Methanolysis of extraction residue from Xianfeng lignite with NaOH and product characterizations with different spectrometries

    Liu, Fang-Jing / Juan Gui / Peng Li / Rui-Lun Xie / Wei-Tu Li / Xian-Yong Wei / Yu-Gao Wang / Zhi-Min Zong

    Fuel Processing Technology. 2015 Aug., v. 136

    2015  

    Abstract: Extraction residue (ER) from Xianfeng lignite via ultrasonic extraction was subjected ...

    Abstract Extraction residue (ER) from Xianfeng lignite via ultrasonic extraction was subjected to methanolysis in the presence of NaOH at 300°C for 2h, and extracts 1–4 (E’1-E’4) from ER methanolysis were acquired by subsequent separation of the resulting soluble portion (SP). NaOH could promote ER methanolysis and hence increased the SP yield. Detailed molecular compositions (MCs) of E’1-E’4 were characterized with Fourier transform infrared spectrometer, gas chromatograph/mass spectrometer (GC/MS), direct analysis in real time ionization source coupled to ion-trap mass spectrometer (DARTIS/ITMS), and atmospheric solid analysis probe/time of flight-mass spectrometer (ASAP/TOF-MS). The results show that the SP is rich in aliphatic moieties, carbonyl and hydroxy groups, and has molecular mass distribution ranging from m/z 100 to 600. According to GC/MS analysis, phenols, especially polymethylphenols, were enriched in E’1 and E’2, whereas almost all the alkanoic acids, alkanedioic acids, benzoic acids, and phenyl-substituted alkanoic acids only appeared in E’4. A series of polar and/or involatile organic species, which are difficult to be detected with GC/MS, were detected with DARTIS/ITMS and ASAP/ TOF-MS. NaOH could play an important role in cleaving ether bonds in ER during methanolysis and thereby enhanced the formation of oxygen-containing organic species. The use of multiple spectrometries provides a promising approach for understanding MC of the SP from coals.
    Keywords benzoic acids ; Fourier transform infrared spectroscopy ; gas chromatography-mass spectrometry ; ionization ; lignite ; methanolysis ; molecular weight ; phenols ; sodium hydroxide ; spectrometers ; ultrasonics
    Language English
    Dates of publication 2015-08
    Size p. 8-16.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 1483666-x
    ISSN 0378-3820
    ISSN 0378-3820
    DOI 10.1016/j.fuproc.2014.07.012
    Database NAL-Catalogue (AGRICOLA)

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  5. Article: Characterization of organonitrogen species in Xianfeng lignite by sequential extraction and ruthenium ion-catalyzed oxidation

    Liu, Fang-Jing / Juan Gui / Peng Li / Wei-Tu Li / Xian-Yong Wei / Xing Fan / Yu-Gao Wang / Yun-Peng Zhao / Zhi-Min Zong

    Fuel processing technology. 2014 Oct., v. 126

    2014  

    Abstract: ... extraction (TE), and ruthenium ion-catalyzed oxidation (RICO), of Xianfeng lignite (XL) was performed ...

    Abstract A three-step degradation, including sequential ultrasonic extraction (UE), sequential thermal extraction (TE), and ruthenium ion-catalyzed oxidation (RICO), of Xianfeng lignite (XL) was performed to characterize the organonitrogen species (ONSs) in XL. More than 87.3% of organic matter in XL was converted into soluble portions through the degradation. The analysis with X-ray photoelectron spectrometer shows that pyrrolic, amino, and quaternary nitrogen species are the main nitrogen forms both in XL and its residue from UE, while nitroaromatics, chemisorbed N-oxides, and pyrrolic nitrogen are predominant in the residue from TE. A series of ONSs, including pyridines, quinolines, benzo[d]imidazoles, and arylamines, were identified in the extracts from TE of the UE residue according to GC/MS analysis. Among the ONSs, pyridines and quinolines are the most abundant. The ONSs could be released by thermally destroying noncovalent bonds, such as hydrogen bonds and aromatic π−π interactions, during TE of the UE residue. Most of ONSs released from RICO of the TE residue could be generated from the degradation of nitrogen-containing macromolecular aromatics in XL matrix (XLM). Nitrobenzenecarboxylic acids are the most abundant ONSs released from RICO of the TE residue and should be released by the degradation of macromolecular nitroaromatics in XLM.
    Keywords carboxylic acids ; gas chromatography-mass spectrometry ; hydrogen bonding ; imidazoles ; lignite ; nitroaromatic compounds ; nitrogen ; organic matter ; oxidation ; pyridines ; quinolines ; ruthenium ; ultrasonics ; X-ray photoelectron spectroscopy
    Language English
    Dates of publication 2014-10
    Size p. 199-206.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 1483666-x
    ISSN 0378-3820
    ISSN 0378-3820
    DOI 10.1016/j.fuproc.2014.05.004
    Database NAL-Catalogue (AGRICOLA)

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  6. Article: Sulfur-containing species in the extraction residue from Xianfeng lignite characterized by X-ray photoelectron spectrometry and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry

    Liu, Fang-Jing / Li, Peng / Li, Zhan-Ku / Wang, Yu-Gao / Wei, Xian-Yong / Zong, Zhi-Min

    RSC advances. 2015 Jan. 02, v. 5, no. 10

    2015  

    Abstract: ... ER) from Xianfeng lignite were characterized through methanolysis combined with X-ray photoelectron ...

    Abstract Understanding the chemical composition of sulfur-containing species (SCSs) in coals is important because of their negative impact on the environment during coal utilization. In this study, SCSs in the extraction residue (ER) from Xianfeng lignite were characterized through methanolysis combined with X-ray photoelectron spectrometry (XPS) and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) analyses. The results show that the SCSs on the ER surface include pyrite, aliphatic sulfur, aromatic sulfur, sulfoxide, sulfone, and sulfate. The S1Ox (x = 0–5), S2Ox (x = 0–5), and N3S1 class species are the main SCSs in the soluble portion from ER methanolysis according to ESI FT-ICR MS analysis. Henicosane-1-thiol and alkylhydroxythiophenecarboxylic acids are dominant in the S1Ox class species. The S2Ox class species have double bond equivalent values of 1–14 and carbon numbers of 16–33. Sulfur in the S2Ox class species is mainly present in thiol groups or S-heterocyclic rings (especially thiophene ring). Methanol can thermally break the –C–O– and –C–S– bonds connected between SCSs and macromolecular moieties in the ER matrix, leading to the release of SCSs.
    Keywords carbon ; carboxylic acids ; chemical bonding ; chemical composition ; electrospray ionization mass spectrometry ; environmental impact ; lignite ; methanol ; methanolysis ; moieties ; pyrite ; sulfates ; sulfur ; thiols ; thiophene ; X-ray photoelectron spectroscopy
    Language English
    Dates of publication 2015-0102
    Size p. 7125-7130.
    Publishing place The Royal Society of Chemistry
    Document type Article
    ISSN 2046-2069
    DOI 10.1039/c4ra12435a
    Database NAL-Catalogue (AGRICOLA)

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  7. Article: Characterization of Oxygen-Containing Species in Methanolysis Products of the Extraction Residue from Xianfeng Lignite with Negative-Ion Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

    Liu, Fang-Jing / Li Peng / Li Wei-Tu / Li Zhan-Ku / Wang Yu-Gao / Wei Xian-Yong / Xie Rui-Lun / Zong Zhi-Min

    Energy & Fuels. 2014 Sept. 18, v. 28, no. 9

    2014  

    Abstract: Methanolysis of an extraction residue (ER) from Xianfeng lignite was carried out to obtain extracts ...

    Abstract Methanolysis of an extraction residue (ER) from Xianfeng lignite was carried out to obtain extracts 1–4 (E₁–E₄). The molecular compositions (MCs) of oxygen-containing species (OCSs) in E₁–E₄ were characterized using negative-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS). In addition, solid-state ¹³C nuclear magnetic resonance and X-ray photoelectron spectrometry were used to analyze the carbon types and oxygen functional groups (OFGs) in the ER. The results show that the carbon skeleton structures in the ER are dominated by aliphatic (50.2%) and aromatic (44.9%) carbons. Methylene and methoxy carbons are the most abundant among the aliphatic carbons. Each aromatic cluster contains three rings on average with two substituent groups on each ring. The OFGs in the ER include hydroxy, ether, carbonyl, and carboxyl groups, among which the hydroxy group is the most abundant. The ESI FT-ICR MS analysis shows that the molecular mass distributions of E₁–E₄ range from 150 to 500 u. The Oₙ (n = 1–6) class species are the predominant OCSs in E₁–E₄, with 0–14 double bond equivalent (DBE) values and 9–34 carbon numbers (CNs). The most abundant Oₙ class species in E₁–E₄ are O₂, O₂, O₂–O₃, and O₃, respectively. The OCSs in E₄ contain low abundances of O₁ and O₂ class species but relatively high abundances of O₄–O₆ class species. In addition, the Oₙ class species in E₄ have narrower ranges of DBE values and CNs than those in E₁–E₃. A series of acidic species with different DBE values and CNs are assigned to alkanoic acids, alkanedioic acids, alkanetricarboxylic acids, alkylarenols, alkylarenediols, alkylarenetriols, and alkylarenoic acids. With high resolving power and mass accuracy, ESI FT-ICR MS is an effective technique for characterizing MC of the soluble portion from lignites, which will facilitate producing important chemicals from lignites.
    Keywords acids ; carbon ; ionization ; lignite ; mass spectrometry ; methanolysis ; molecular weight ; nuclear magnetic resonance spectroscopy ; oxygen ; ozone ; stable isotopes ; superoxide anion ; X-ray photoelectron spectroscopy
    Language English
    Dates of publication 2014-0918
    Size p. 5596-5605.
    Publishing place American Chemical Society
    Document type Article
    ZDB-ID 1483539-3
    ISSN 1520-5029 ; 0887-0624
    ISSN (online) 1520-5029
    ISSN 0887-0624
    DOI 10.1021%2Fef501414g
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  8. Book ; Online: Flow-Guided Controllable Line Drawing Generation

    Fang, Chengyu / Han, Xianfeng

    2023  

    Abstract: In this paper, we investigate the problem of automatically controllable artistic character line drawing generation from photographs by proposing a Vector Flow Aware and Line Controllable Image-to-Image Translation architecture, which can be viewed as an ... ...

    Abstract In this paper, we investigate the problem of automatically controllable artistic character line drawing generation from photographs by proposing a Vector Flow Aware and Line Controllable Image-to-Image Translation architecture, which can be viewed as an appealing intersection between Artificial Intelligence and Arts. Specifically, we first present an Image-to-Flow network (I2FNet) to efficiently and robustly create the vector flow field in a learning-based manner, which can provide a direction guide for drawing lines. Then, we introduce our well-designed Double Flow Generator (DFG) framework to fuse features from learned vector flow and input image flow guaranteeing the spatial coherence of lines. Meanwhile, in order to allow for controllable character line drawing generation, we integrate a Line Control Matrix (LCM) into DFG and train a Line Control Regressor (LCR) to synthesize drawings with different styles by elaborately controlling the level of details, such as thickness, smoothness, and continuity, of lines. Finally, we design a Fourier Transformation Loss to further constrain the character line generation from the frequency domain view of the point. Quantitative and qualitative experiments demonstrate that our approach can obtain superior performance in producing high-resolution character line-drawing images with perceptually realistic characteristics.
    Keywords Computer Science - Computer Vision and Pattern Recognition ; Computer Science - Multimedia
    Subject code 004
    Publishing date 2023-07-14
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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    Inter-library loan at ZB MED

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  9. Article ; Online: Confocal microscopic and dermoscopic features of eccrine poroma: A case report.

    Wu, Weiwei / Xiong, Chengcheng / Zhang, Yan / Fang, Xianfeng

    Skin research and technology : official journal of International Society for Bioengineering and the Skin (ISBS) [and] International Society for Digital Imaging of Skin (ISDIS) [and] International Society for Skin Imaging (ISSI)

    2022  Volume 28, Issue 4, Page(s) 643–645

    MeSH term(s) Dermoscopy/methods ; Humans ; Microscopy, Confocal ; Poroma/diagnostic imaging ; Sweat Gland Neoplasms/diagnostic imaging
    Language English
    Publishing date 2022-05-31
    Publishing country England
    Document type Case Reports ; Letter
    ZDB-ID 1229160-2
    ISSN 1600-0846 ; 0909-752X ; 1397-1344
    ISSN (online) 1600-0846
    ISSN 0909-752X ; 1397-1344
    DOI 10.1111/srt.13174
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    In stock of ZB MED Cologne/Königswinter

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  10. Article: Relationships between the Mini-InDel Variants within the Goat

    Mi, Fang / Wu, Xianfeng / Wang, Zhen / Wang, Ruolan / Lan, Xianyong

    Animals : an open access journal from MDPI

    2022  Volume 12, Issue 24

    Abstract: The cilia- and flagella-associated protein 43 ( ...

    Abstract The cilia- and flagella-associated protein 43 (
    Language English
    Publishing date 2022-12-07
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2606558-7
    ISSN 2076-2615
    ISSN 2076-2615
    DOI 10.3390/ani12243447
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