FIBERS AND POLYMERS
·
2018
·Vol. 19
·期 8
·1611-1617
·
IF 1.353
Wang Cuie,Wang Ning,Liu Xinhua,Wan Peng,He Xinwei,Shang Yongjia
We propose a green synthesis of benzopyran compound based on immobilized lipase. Firstly, by using a combined electrospun membrane and biocompatible chitosan, we show that the chitosan-functionalized electrospun PMA-co-PAA fibrous membrane can provide effective anchoring sites for immobilization of the Candida antarctica lipase B (CALB), and a maximum loading amount of CALB (152 mg/g) can be achieved. Then, the resulting membrane displays enhanced stability in catalyzing Knoevenagel condensation reaction of salicylaldehyde with active methylene compound in mixed aqueousorganic media. The catalytic activity and stability of the CALB on chitosan-modified fiber is better than its non-immobilized counterpart. Furthermore, this immobilize CALB catalyst still retained about 45 % of the initial activity after 5 cycles, which potentially had implications for the design of “green” enzyme catalyst for sustainable organic synthesis.
研究领域:
生物化学
·
绿色化学
·
材料科学
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2015
·
IF 3.391
Fang-Yuan Fan,Meng Shi,Ying Nie,Yue Zhao,Jian-Hui Ye,Yue-Rong Liang
Tea catechins as a member of flavan-3-ols subclass with the same skeleton may behave differentially. This study investigated the chemical conversions of 8 catechins under heat treatment with the involvement of epimerization, hydrolysis and oxidation/condensation reactions. Three reactions were enhanced as temperature increased from 30 °C to 90 °C. The epimerization of non-gallated catechins was favored by epi-configuration but hindered by pyrogallol moiety, and the hydrolysis reaction of gallated catechins was facilitated by pyrogallol moiety. Epicatechin and epigallocatechin had the lowest thermostabilities due to epimerization and oxidation/condensation reactions respectively. Sufficient O 2 was not a precondition for the occurrence of chemical conversions of catechins under heat treatment. Non-enzymatic oligomerization occurred to epi type catechins and catechin under heat treatment, and dehydrodicatechins A were mainly responsible for the browning of epicatechin and catechin solutions. The evidence of generation of catechin oligomers provides a novel way to explain sensory change of tea and relevant products during thermal processing.
研究领域:
食品科学
·
植物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2020
·
IF 3.408
Hongyao Ding,Xiaoxu Liang,Si Yu Zheng,Qiao Wang,Zongjin Li,Guoxing Sun
Hydrogel-based actuators have attracted much attention and shown promising applications in many fields. However, it remains a challenge to assemble two hydrogel sheets into a double-layer actuator due to their slippery and non-adhesive nature. Herein, we present a simple and reliable strategy that allows two hydrogel sheets to be bonded together well with chemical bonds formed in condensation reactions, only requiring interfacial contact and then heat-treatment. The results shown that the condensation reactions can occur under heat-treatment and that the two hydrogel layers have good interfacial bonding. The double-layer strip hydrogels prepared in this method showed different deformation rate and bending extent, which can be well tuned by changing internal structures and external stimuli. Complex and controllable three-dimensional shapes of the assembled blocks can be obtained through well-tailored structures. A four-arm gripper prepared in this approach can implement the grasping and releasing an object quickly with different stimuli. This work provides a facile approach in achieving hydrogel bonding and preparing intelligent double-layer soft actuators .
研究领域:
材料科学
·
生物医学工程
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DOI
高影响因子
CATALYSIS TODAY
·
2024
·
IF 5.2
Jipeng Wang,Xinli Tong,Chen Guo,Yahui Wei
The high entropy oxides are widely studied as the potential catalytic materials owing to their unique structure and excellent properties. In this work, a new high entropy oxide catalyst MnFeCoNiCuO x was successfully prepared and used for the oxidative condensation reaction of furfural (FUR) and aliphatic alcohol , where the carbon-chain length can be selectively increased under the mild conditions. For the selective oxidative transformation of FUR with n-butanol, a more than 99.0 % conversion of FUR and 91.5 % selectivity of 2-(furanyl-2-methylene) butanal was obtained at 80 ºC for 2 h. In addition, the oxidative condensation of FUR with ethanol, n-propanol, n-pentanol, n-hexanol and n-heptanol was also carried out with the MnFeCoNiCuO x - LiOH as catalyst system in the presence of molecular oxygen , where a moderate to high product yields were acquired. Furthermore, the characterizations of catalyst showed that the existence of abundant oxygen vacancy and high specific area was greatly important to the catalytic reactions .
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Molbank
·
2023
·Vol. 2023
·期 2
·M1664
·
IF 0.6
Lingsen Li,Jingjing Wang,Tianhao Gong,Kunming Liu,Juanhua Li
In this short note, we elaborate on a synthetic method for a new terpyridine Schiff base-bearing vanillin motif. The structure of the product was confirmed via1H and13C-NMR spectroscopy and FT-IR spectroscopy. Due to the peculiar coordination nature and optical property of the synthesized compound, this work presents a promising colorimetric sensing molecular compound.Keywords:terpyridine derivatives;Schiff base;condensation
研究领域:
化学
·
材料科学
✓ 已验证
DOI
高影响因子
Tungsten
·
2024
·
IF 5.6
Chen Hao,Wang Ya-Qin,Zhang Dong-Ting,Zhao Bei,Li Min-Peng,Li Chen-Yang,Xu Tian-Peng,Liu Mao-Cheng
MXenes obtained significant attention in the field of energy storage devices due to their characteristic layered structure, modifiable surface functional groups, large electrochemically active surface, and regulable interlayer spacing. Nonetheless, the self-restacking and sluggish ions diffusion kinetics performance of MXenes during the alkali metal ions insertion/extraction process severely impedes their cycle stability and rate capability. This paper proposes an aniline molecule welding strategy for welding p-phenylenediamine (PPDA) into the interlayers of Ti 2 C through a dehydration condensation reaction. The welded PPDA molecules can contribute pillar effect to the layered structure of Ti 2 C. The pillar effect effectively maintains the structural stability during the sodium ions insertion/extraction process and effectively expands the interlayer spacing of Ti 2 C from 1.16 to 1.38 nm, thereby enhancing ions diffusion kinetics performance and improving the long-term cycle stability. The Ti 2 C-PPDA demonstrates outstanding Na + storage capability, exhibiting a specific capacity of 100.2 mAh·g −1 at a current density of 0.1 A·g −1 over 960 cycles and delivering a remarkable rate capability 81.2 mAh·g −1 at a current density of 5 A·g −1 . The study demonstrates that expanding interlayer spacing is a promising strategy to enhance the Na + storage capacity and improve long-term cycling stability, which provides significant guidance for the design of two-dimensional Na + storage materials with high-rate capability and cycle stability.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 19
·6985
·
IF 4.6
Shulin Wang,Haidong Teng,Lan Wang,Pengcheng Li,Xinghao Yuan,Xi Sang,Jianping Wu,Lirong Yang,Gang Xu
Peptides have demonstrated their efficacy as catalysts in asymmetric aldol reactions. But the constraints inherent in chemical synthesis have imposed limitations on the viability of long-chain peptide catalysts. A noticeable dearth of tools has impeded the swift and effective screening of peptide catalysts using biological methods. To address this, we introduce a straightforward bioprocess for the screening of peptide catalysts for asymmetric aldol reactions. We synthesized several peptides through this method and obtained a 15-amino acid peptide. This peptide exhibited asymmetric aldol catalytic activity, achieving 77% ee in DMSO solvent and 63% ee with over an 80.8% yield in DMSO mixed with a pH 9.0 buffer solution. The successful application of our innovative approach not only represents an advancement but also paves the way for currently unexplored research avenues.Keywords:peptide catalysis;asymmetric aldol reaction;fusion protein;simple bioprocess
研究领域:
化学生物学
·
有机化学
·
生物催化
✓ 已验证
DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2017
·Vol. 7
·期 16
·3555-3561
·
IF 5.773
Mingxue Su,Wenzhi Li,Tingwei Zhang,HaoSheng Xin,Song Li,Wei Fan,Longlong Ma
Aldol condensation reactions between furfural and acetone can be used to produce liquid fuel intermediates. It was found that tin-containing zeolites with MFI (Sn-MFI) and BEA* (Sn-Beta) framework structures are effective for C–C bond formation via the aldol condensation reactions between furfural and acetone. Aldol condensation between furfural and acetone produced two main products, 4-(2-furyl)-3-buten-2-one (FAc) and 1,5-di-2-furanyl-1,4-pentadien-3-one (F2Ac). Although both these catalysts were active for the aldol condensation reactions, different selectivities to aldol products were observed over Sn-MFI and Sn-Beta. FAc and F2Ac were formed over the Sn-Beta catalyst with selectivities to FAc of 40% and F2Ac of 22%, respectively. In contrast, only FAc was produced over Sn-MFI. The variation in selectivity is likely due to different pore geometries of Sn-Beta and Sn-MFI, suggesting that Sn-MFI exhibits shape selectivity for aldol condensation between furfural and acetone. In addition, it was found that the addition of water to the reaction system can also affect the product selectivity, leading to the aldol product exclusively being FAc over Sn-Beta.
研究领域:
化学工程
·
催化科学
·
可再生能源
✓ 已验证
DOI
高影响因子
ChemSusChem
·
2024
·Vol. 17
·期 12
·e202301681
·
IF 7.5
Jing Yi,Yuze Dai,Yuxuan Li,Yuhao Zhao,Yuanpeng Wu,Min Jiang,Guangyuan Zhou
Graphical A green and sustainable −COOH & −OH condensation solution polymerization method for FDCA-based polyesters. A green and sustainable −COOH & −OH condensation solution polymerization method was hereby reported for FDCA-based polyesters to avoid discoloration and toxic solvents. First, taking poly(ethylene 2,5-furandicarboxylate) (PEF) as the representative of FDCA-based polyester, enabling good white appearance PEF with M n =6.51×10 3 g mol −1 from FDCA and ethylene glycol in green solvent γ-valerolactone (GVL), catalyzed by 4-dimethylaminopyridine (DMAP) and N-(3-dimethylaminopropyl)-N’-ethylcarbodiimide hydrochloride (EDC). Additionally, the molecular weight of PEF was rapidly improved ( M n >2.5×10 4 g mol −1 ) via remelting polycondensation within minutes, with the dispersity still kept relatively low dispersity ( Đ <1.40). Importantly, the −COOH & −OH condensation solution polymerization method was successfully applied for the synthesis of various FDCA-based polyesters, including diols with varying carbon chain lengths (3 to 11 carbons) and cycloalkyl diols, especially the applicability of this method to diols containing C=C double bonds, which was found to exhibit low heat resistance. Lastly, assisting with 13 C labeled 1,4-succinic acid and in-situ 13 C-NMR, an in-depth study of the possible catalytic mechanism was proposed, by which, EDC activated FDCA, and then DMAP catalyzed it with diol to yield macromolecular chain of polyester. Overall, the results provided a green and sustainable strategy for the synthesis of FDCA-based polyesters.
研究领域:
材料科学
·
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 32
·e52765
·
IF 3.057
Pengjia Shan,Hengyu Lu,Ning Chen,Hongzhi Liu,Xianhui Zhang,Xiaohuan Liu
Designing biobased hyperbranched polyesters from vegetable oil has been attracting considerable interests from academic industrial communities. Herein, a novel fully biobased hyperbranched polyester (HBPE) was prepared by self-condensation of AB 2 -type bioderived monomer based on methyl ricinoleate (MR), a castor oil-derived renewable chemical. The reaction conditions were optimized to obtain the AB 2 -type monomer in a high conversion ratio (up to 87%). The self-condensation of AB 2 -type monomers was carried out in the presence of two kinds of transesterification catalysts (Ti(OBu) 4 versus Zn(Ac) 2 ), among which Ti(OBu) 4 was found to be more efficient one and yield higher molecular weights in the range of 5800~11,500 g/mol. The resulting HBPEs were characterized in terms of Fourier transform infrared spectroscopy, nuclear magnetic resonance, differential scanning calorimetry, and thermogravimetric analysis. The degree of branching was calculated to be 0.33~0.39. Thermal analysis revealed that the as-prepared HBPEs were amorphous with tunable glass transition temperatures ranging from −44.8 to −24.6°C. All the prepared HBPEs exhibited good thermal stability with the maximum onset decomposition temperature ( T onset ) up to 294.6°C. These structural features and properties of resulting biobased HBPEs enabled them to act as a potential ‘greener’ additive for polymers.
研究领域:
材料科学
·
生物基材料
·
有机化学
✓ 已验证
DOI
高影响因子
Analytical Methods
·
2017
·Vol. 9
·期 37
·5472-5477
·
IF 1.9
Feng Wu,Yue Zhang,Lei Huang,Dan Xu,Hongying Wang
A simple anthracene carboxyimide-based fluorescent probe has been readily developed for the detection of toxic formaldehyde (FA). The probe displays a remarkable fluorescence turn-on response towards FA based on the aldimine condensation reaction, which was confirmed by the HR-MS spectrum. The probe can quantitatively determine the level of FA with high selectivity and fast response (within 3 min). Furthermore, cell staining experiments indicate that the probe was cell membrane permeable and could be used for imaging FA in living cells with good performance. Therefore, this probe has promising applications for the detection of FA in living cells.
研究领域:
分析化学
·
生物化学
·
细胞生物学
✓ 已验证
DOI
高影响因子
CATALYSIS LETTERS
·
2017
·Vol. 147
·期 9
·2410-2420
·
IF 2.799
Zanon Adriano,Chaemchuen Somboon,Verpoort Francis
Abstract Three different bimetallic zinc-cobalt zeolitic imidazolate frameworks (ZIFs) were successfully synthesized at room temperature in water through a green and simple procedure and tested as catalysts for the Knoevenagel condensation reaction between p -Br-benzaldehyde and malononitrile as model reaction. The materials were characterized with various techniques (XRD, ICP-AES, SEM, N 2 adsorption–desorption, TGA) and displayed excellent activities and selectivities. Moreover, the crystalline structure was preserved and the catalysts could be reused at least four times with negligible loss of activity. Graphical Abstract
研究领域:
化学
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）