LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 161

Search options

  1. Article ; Online: Synthesis of γ-Valerolactone from Carbohydrates and its Applications.

    Zhang, Zehui

    ChemSusChem

    2016  Volume 9, Issue 2, Page(s) 156–171

    Abstract: γ-Valerolactone (GVL) is a valuable chemical intermediate that can be obtained by catalytic reduction of levulinic acid (LA) or alkyl levulinates (AL). There are many reports on the synthesis of GVL from LA or AL. However, the demand for the large-scale ... ...

    Abstract γ-Valerolactone (GVL) is a valuable chemical intermediate that can be obtained by catalytic reduction of levulinic acid (LA) or alkyl levulinates (AL). There are many reports on the synthesis of GVL from LA or AL. However, the demand for the large-scale synthesis of GVL requires more environmentally friendly and cost-effective production processes. This article focuses on the recent advance in the synthesis of GVL from carbohydrates or lignocellulosic biomass. In addition, application of GVL as the reaction solvents, fuel additives, and as precursor for the synthesis of jet fuel and polymer monomers is also discussed.
    MeSH term(s) Biofuels ; Carbohydrates/chemistry ; Chemistry Techniques, Synthetic/methods ; Humans ; Lactones/chemical synthesis ; Lactones/chemistry ; Lignin/chemistry ; Solvents
    Chemical Substances Biofuels ; Carbohydrates ; Lactones ; Solvents ; lignocellulose (11132-73-3) ; Lignin (9005-53-2) ; gamma-valerolactone (O7056XK37X)
    Language English
    Publishing date 2016-01
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ISSN 1864-564X
    ISSN (online) 1864-564X
    DOI 10.1002/cssc.201501089
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  2. Article ; Online: Hydrogen-Bond-Mediated Formation of C-N or C=N Bond during Photocatalytic Reductive Coupling Reaction over CdS Nanosheets.

    He, Jie / Han, Bo / Xian, Chensheng / Hu, Zhao / Fang, Tingfeng / Zhang, Zehui

    Angewandte Chemie (International ed. in English)

    2024  , Page(s) e202404515

    Abstract: Reductive amination of carbonyl compounds and nitro compounds represents a straightforward way to attain imines or secondary amines, but it is difficult to control the product selectivity. Herein, we report the selective formation of C-N or C=N bond ... ...

    Abstract Reductive amination of carbonyl compounds and nitro compounds represents a straightforward way to attain imines or secondary amines, but it is difficult to control the product selectivity. Herein, we report the selective formation of C-N or C=N bond readily manipulated through a solvent-induced hydrogen bond bridge, facilitating the swift photocatalytic reductive coupling process. The reductive-coupling of nitro compounds with carbonyl compounds using formic acid and sodium formate as the hydrogen donors over CdS nanosheets selectively generates imines with C=N bonds in acetonitrile solvent; while taking methanol as solvent, the C=N bonds are readily hydrogenated to the C-N bonds via hydrogen-bonding activation. Experimental and theoretical study reveals that the building of the hydrogen-bond bridge between the hydroxyl groups in methanol and the N atoms of the C=N motifs in imines facilitates the transfer of hydrogen atoms from CdS surface to the N atoms in imines upon illumination, resulting in the rapid hydrogenation of the C=N bonds to give rise to the secondary amines with C-N bonds. Our method provides a simple way to control product selectivity by altering the solvents in photocatalytic organic transformations.
    Language English
    Publishing date 2024-04-18
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.202404515
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  3. Article ; Online: In Vitro Anti-Tumor and Hypoglycemic Effects of Total Flavonoids from Willow Buds.

    Zhang, Peng / Fan, Lulu / Zhang, Dongyan / Zhang, Zehui / Wang, Weili

    Molecules (Basel, Switzerland)

    2023  Volume 28, Issue 22

    Abstract: ... Salix ... ...

    Abstract Salix babylonica
    MeSH term(s) Humans ; Flavonoids/pharmacology ; Flavonoids/analysis ; Hypoglycemic Agents/pharmacology ; Hypoglycemic Agents/analysis ; Salix ; Plant Extracts/pharmacology ; Plant Extracts/analysis ; Chromatography, Liquid ; HeLa Cells ; alpha-Glucosidases ; Tandem Mass Spectrometry ; alpha-Amylases
    Chemical Substances Flavonoids ; Hypoglycemic Agents ; Plant Extracts ; alpha-Glucosidases (EC 3.2.1.20) ; alpha-Amylases (EC 3.2.1.1)
    Language English
    Publishing date 2023-11-13
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 1413402-0
    ISSN 1420-3049 ; 1431-5165 ; 1420-3049
    ISSN (online) 1420-3049
    ISSN 1431-5165 ; 1420-3049
    DOI 10.3390/molecules28227557
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    In stock of ZB MED Cologne/Königswinter

    Zs.MO 81: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  4. Article: Repair Strategy for Epoxy Anticorrosive Coatings on Steel Structures.

    Tu, Kun / Wu, Jin / Zhao, Xing / Zhang, Lifang / Zhang, Zehui

    Materials (Basel, Switzerland)

    2023  Volume 16, Issue 18

    Abstract: This paper presents the results of a test of epoxy anticorrosion coating repair. Two strategies of coating repair were studied, respectively: partial repair and integral repair. The gloss loss rate, color difference and rust area rate of the repair ... ...

    Abstract This paper presents the results of a test of epoxy anticorrosion coating repair. Two strategies of coating repair were studied, respectively: partial repair and integral repair. The gloss loss rate, color difference and rust area rate of the repair coating were measured. The anticorrosion performance of repair coatings under different repair methods was compared. Based on the results of the coating repair test, the repair criteria for coatings were defined, and the repair strategy for epoxy anticorrosive coatings on steel structure was proposed. The results show that Marathon 500 super abrasion resistant epoxy paint (M500) and Jotamastic 90 GF low surface treatment epoxy abrasion resistant glass flake paint (J90GF) are suitable for partial repair of epoxy anticorrosive coatings on steel structures, and that Jotamastic 90 low surface treatment epoxy abrasion resistant coating (J90) and Marathon 500 super abrasion resistant epoxy paint (M500) are suitable for integral repair of epoxy anticorrosive coatings on steel structures.
    Language English
    Publishing date 2023-09-18
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2487261-1
    ISSN 1996-1944
    ISSN 1996-1944
    DOI 10.3390/ma16186257
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  5. Article ; Online: Biomass-Derived Single Zn Atom Catalysts: The Multiple Roles of Single Zn Atoms in the Oxidative Cleavage of C-N Bonds.

    Qin, Jingzhong / Han, Bo / Lu, Xiaomei / Nie, Jiabao / Xian, Chensheng / Zhang, Zehui

    JACS Au

    2023  Volume 3, Issue 3, Page(s) 801–812

    Abstract: The C-N bond cleavage represents one kind of important organic and biochemical transformation, which has attracted great interest in recent years. The oxidative cleavage of C-N bonds ... ...

    Abstract The C-N bond cleavage represents one kind of important organic and biochemical transformation, which has attracted great interest in recent years. The oxidative cleavage of C-N bonds in
    Language English
    Publishing date 2023-02-16
    Publishing country United States
    Document type Journal Article
    ISSN 2691-3704
    ISSN (online) 2691-3704
    DOI 10.1021/jacsau.2c00605
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  6. Article ; Online: Deep Learning-Aided Modulation Recognition for Non-Orthogonal Signals.

    Fan, Jiaqi / Wu, Linna / Zhang, Jinbo / Dong, Junwei / Wen, Zhong / Zhang, Zehui

    Sensors (Basel, Switzerland)

    2023  Volume 23, Issue 11

    Abstract: Automatic Modulation Recognition (AMR) can obtain the modulation mode of the received signal for subsequent processing without the assistance of the transmitter. Although the existing AMR methods have been mature for the orthogonal signals, these methods ...

    Abstract Automatic Modulation Recognition (AMR) can obtain the modulation mode of the received signal for subsequent processing without the assistance of the transmitter. Although the existing AMR methods have been mature for the orthogonal signals, these methods face challenges when deployed in non-orthogonal transmission systems due to the superimposed signals. In this paper, we aim to develop efficient AMR methods for both downlink and uplink non-orthogonal transmission signals using deep learning-based data-driven classification methodology. Specifically, for downlink non-orthogonal signals, we propose a Bi-directional Long Short-Term Memory (BiLSTM)-based AMR method that exploits long-term data dependence to automatically learn irregular signal constellation shapes. Transfer learning is further incorporated to improve recognition accuracy and robustness under varying transmission conditions. For uplink non-orthogonal signals, the combinatorial number of classification types explodes exponentially with the number of signal layers, which becomes the major obstacle to AMR. We develop a spatio-temporal fusion network based on the attention mechanism to efficiently extract spatio-temporal features, and network details are optimized according to the superposition characteristics of non-orthogonal signals. Experiments show that the proposed deep learning-based methods outperform their conventional counterparts in both downlink and uplink non-orthogonal systems. In a typical uplink scenario with three non-orthogonal signal layers, the recognition accuracy can approach 96.6% in the Gaussian channel, which is 19% higher than the vanilla Convolution Neural Network.
    MeSH term(s) Deep Learning ; Memory, Long-Term ; Neural Networks, Computer ; Normal Distribution ; Recognition, Psychology
    Language English
    Publishing date 2023-05-31
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2052857-7
    ISSN 1424-8220 ; 1424-8220
    ISSN (online) 1424-8220
    ISSN 1424-8220
    DOI 10.3390/s23115234
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  7. Article ; Online: Aerobic oxidative C-C bond cleavage and functionalization for the synthesis of value-added chemicals.

    Zhou, Peng / Yuan, Ziliang / He, Jie / Fang, Tingfeng / Liu, Bing / Zhang, Zehui

    Chemical communications (Cambridge, England)

    2023  Volume 59, Issue 80, Page(s) 11923–11931

    Abstract: The aerobic oxidative cleavage of C-C bonds is an attractive and sustainable route for constructing valuable molecules such as esters, nitriles, and amides. Traditionally homogeneous catalytic systems for C-C bond cleavage required harsh conditions, ... ...

    Abstract The aerobic oxidative cleavage of C-C bonds is an attractive and sustainable route for constructing valuable molecules such as esters, nitriles, and amides. Traditionally homogeneous catalytic systems for C-C bond cleavage required harsh conditions, stoichiometric oxidants, and noble metal catalysts to overcome the thermodynamic and kinetic barriers of C-C bonds, imposing environmental concerns of the transformation. Therefore, developing efficient, low-cost, and environmentally benign methods for C-C bond cleavage is of great importance and a cutting-edge area in modern chemistry. This feature article summarizes the sustainable aerobic oxidative C-C bond cleavage method developed by our group in the past 5 years. Fundamental principles in catalyst design, substrate scope, and mechanism for C-C bond cleavage are also discussed.
    Language English
    Publishing date 2023-10-05
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 1472881-3
    ISSN 1364-548X ; 1359-7345 ; 0009-241X
    ISSN (online) 1364-548X
    ISSN 1359-7345 ; 0009-241X
    DOI 10.1039/d3cc03820c
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  8. Article: Influence of Leader Mindfulness on the Emotional Exhaustion of University Teachers: Resources Crossover Effect.

    Liu, Beini / Zhang, Zehui / Lu, Qiang

    Frontiers in psychology

    2021  Volume 12, Page(s) 597208

    Abstract: This study combined conservation of resources theory with the job demands-resources model to explore the influence of leader mindfulness on the emotional exhaustion of university teachers Using a time-lagged research design, 388 paired data sets were ... ...

    Abstract This study combined conservation of resources theory with the job demands-resources model to explore the influence of leader mindfulness on the emotional exhaustion of university teachers Using a time-lagged research design, 388 paired data sets were gathered. Multiple regression and bootstrapping were used to test each hypothesis. The results showed that first, leader mindfulness significantly reduces the emotional exhaustion of university teachers. Second, the results showed that workplace telepressure partially mediates the relationship between leader mindfulness and the emotional exhaustion of university teachers. Third, university teacher mindfulness positively moderates the relationship between leader mindfulness and workplace telepressure. Finally, the results of this study indicate that self-efficacy in managing negative emotions negatively moderates the relationship between workplace telepressure and the emotional exhaustion of university teachers. This study empirically examined the interpersonal influence of leader mindfulness and the initial resources effect of university teacher mindfulness and self-efficacy in managing negative emotions from the bilateral perspective of leaders and university teachers.
    Language English
    Publishing date 2021-02-24
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2563826-9
    ISSN 1664-1078
    ISSN 1664-1078
    DOI 10.3389/fpsyg.2021.597208
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  9. Article ; Online: Unexpected higher corrosion in the gas phase region of metals caused by calcium and magnesium ions compared to sodium ions.

    Luo, Yi / He, Zhenglin / Yang, Huayan / Li, Yunzhang / Yue, Dongting / Zhang, Zehui / Shi, Guosheng

    Physical chemistry chemical physics : PCCP

    2023  Volume 25, Issue 32, Page(s) 21428–21435

    Abstract: In the marine environment, ... ...

    Abstract In the marine environment, Na
    Language English
    Publishing date 2023-08-16
    Publishing country England
    Document type Journal Article
    ZDB-ID 1476244-4
    ISSN 1463-9084 ; 1463-9076
    ISSN (online) 1463-9084
    ISSN 1463-9076
    DOI 10.1039/d3cp01571h
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  10. Article ; Online: Synergy of Oxygen Vacancies and Base Sites for Transfer Hydrogenation of Nitroarenes on Ceria Nanorods.

    Yuan, Ziliang / Huang, Liang / Liu, Yuanshuai / Sun, Yong / Wang, Guanghui / Li, Xun / Lercher, Johannes A / Zhang, Zehui

    Angewandte Chemie (International ed. in English)

    2024  Volume 63, Issue 9, Page(s) e202317339

    Abstract: ... ...

    Abstract CeO
    Language English
    Publishing date 2024-01-17
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.202317339
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

To top