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1.
Xiaopeng Yue Yongjian Xu Nina Gou Hongkui Li 《Polymer-Plastics Technology and Engineering》2015,54(6):639-646
A long fatty side chain was introduced into the macromolecule of hydroxyethyl cellulose (HEC) via esterification reaction. The hydrophobicity of hydroxyethyl cellulose lauric acid ester (HECLAE) was enhanced in comparison with HEC. The obtained HECLAE was used as macromolecular coupling agent in poly (butylene succinate)/wood flour composites and exhibited a positive influence on improving the mechanical performance of composites. Besides, HECLAE plays a role as a hydrophobic agent in composites. A significant increase in storage modulus (E’) was observed upon the incorporation of treated wood flour. SEM images showed that the dispersion of treated wood flour in PBS matrix was improved. 相似文献
2.
《International Journal of Hydrogen Energy》2020,45(19):11062-11076
Cyclohexanone is largely generated in the direct or indirect conversion of lignin-derived bio-oils. Hence, the upgrading of cyclohexanone, i.e. deoxygenation in the presence of hydrogen is of great interest. In this regard, two nickel-molybdenum catalysts on alumina support were investigated in the temperatures up to 400 °C and pressures up to 15 bar. High activity, selectivity, and yield were achieved by utilizing these catalysts at the studied condition. The main products of the upgrading of cyclohexanone were C6, C7, and C12 cyclic, aromatic, and bicyclic including cyclohexane, cyclohexene, benzene, and cyclohexylbenzene. The results of the present study imply that these catalysts are beneficial in producing hydrocarbon-rich products from cyclohexanone and lignin-derived bio-oils. Based on the achievements of the present study, the nickel-molybdenum catalyst composed of 1.14 wt% nickel and 14.27 wt% molybdenum showed about 87%, 100%, and 116% conversion of cyclohexanone, total hydrocarbon selectivity, and total hydrocarbon yield, respectively. The optimum condition for obtaining such results was at 400 °C and 8 bar. 相似文献
3.
Preparation and characterisation of soya milk enriched with isoflavone aglycone fermented by lactic acid bacteria combined with hydrothermal cooking pretreatment 下载免费PDF全文
Juan Yang Zhining Bao Nana Wu Xiaoquan Yang Weifeng Lin Zhong Chen Jinmei Wang Jian Guo 《International Journal of Food Science & Technology》2015,50(6):1331-1337
A fermented soya milk (FSM) enriched with isoflavone aglycone (FSM‐SPIA) was prepared from heated soya protein isolate (SPI)‐isoflavone complex. After 48 h of fermentation, FSM‐SPIA contained higher contents of living bacteria, free amino acids and aglycone compared with the FSM of SPI (FSM‐SPI) and the FSM of SPI‐isoflavone complex (FSM‐Mix). In the in‐vitro digestion experiment, FSM‐SPIA showed higher antioxidant capacity and isoflavones (ISO) bioavailability than FSM‐SPI and FSM‐Mix. This was likely due to the soya milk containing a higher level of amino acid, peptides and the presence of soya bean isoflavone. The improved protein digestibility, the interaction and binding ability between proteins and ISO may affect the properties of the protein and the fermented products. The FSM enriched with isoflavone aglycone can be used as a functional fermented drink, as well as an auxiliary food for menopausal women during a specific pathological period. 相似文献
4.
《Ceramics International》2020,46(6):7888-7895
Graphite carbon nitride (g-C3N4) is an appealing metal-free photocatalyst for hydrogen evolution, but the potential has been limited by its poor visible-light absorption and unsatisfactory separation of photo-induced carriers. Herein, a facile one-pot strategy to fabricate carbon self-doped g-C3N4 composite through the calcination of dicyanamide and trace amounts of dimethylformamide is presented. The as-obtained carbon self-doped catalyst is investigated by X-ray photoelectron spectroscopy (XPS), confirming the substitution of carbon atoms in original sites of bridging nitrogen. We demonstrate that the as-prepared materials display remarkably improved visible-light absorption and optimized electronic structure under the premise of principally maintaining the tri-s-triazine based crystal framework and surface properties. Furthermore, the carbon doped g-C3N4 composite simultaneously weakens the transportation barrier of charge carriers, suppresses charge recombination and raises the separated efficiency of photoinduced holes and electrons on account of the extension of pi conjugated system. As a result, carbon self-doped g-C3N4 exhibits 4.3 times greater photocurrent density and 5.2 times higher hydrogen evolution rate compared with its bulk counterpart under visible light irradiation. 相似文献
6.
7.
《Ceramics International》2019,45(8):9799-9806
(Nb1-xTax)4AlC3 (x = 0–0.5) ceramics were prepared by the hot press sintering method. The XRD results show that the second phase (Nb1-xTax)C is formed when the Ta content increases to 25 mol%. The SEM micrographs show that (Nb1-xTax)C has a core/rim structure, whose formation mechanism was also investigated. Substituting some Ta for Nb can significantly improve the mechanical properties of Nb4AlC3. (Nb0.75Ta0.25)4AlC3 exhibits an excellent fracture toughness of 8.3 ± 0.3 MPa m1/2 at room temperature (RT). The highest Young's modulus (349 ± 16 GPa) and Vickers hardness (4.5 ± 0.3 GPa) at RT are exhibited by the (Nb0.5Ta0.5)4AlC3 sample, which correlate to increases of 18% and 80%, respectively, compared with those of Nb4AlC3. The flexural strengths of (Nb0.5Ta0.5)4AlC3 are 439 ± 18 MPa at RT and 344 ± 22 MPa at 1100 °C, which correlate to increases of 27% and 45%, respectively, compared with those of Nb4AlC3. The solid solution of Ta and the formation of (Nb1-xTax)C are beneficial to the strengthening of Nb4AlC3. The coefficient of thermal expansion (CTE) increases slightly from 7.08 × 10−6 K−1 for Nb4AlC3 to 7.24 × 10−6 K−1 for (Nb0.75Ta0.25)4AlC3 at 25–1400 °C. The thermal conductivity of (Nb0.75Ta0.25)4AlC3 (28.4–29.8 W/m·K) is higher than that of Nb4AlC3 (18.1–21.2 W/m·K) over the whole test range (25–1000 °C). Owing to their excellent mechanical and thermal properties, Ta-doped Nb4AlC3 ceramics have good potential as structural materials. 相似文献
8.
9.
Lime mud CaCO3 for use as a filler material in papermaking: Impact of its preflocculation with cationic polyacrylamide 下载免费PDF全文
Cationic polyacrylamide with different molecular weights were used to preflocculate the lime mud (LM) before it was added to the paper stock for handsheet preparation. The particle sizes, ζ potential, and morphology of the unpreflocculated and resulting preflocculated LM were studied. We found that high‐molecular‐weight cationic polyacrylamide (H‐CPAM) led to larger LM flocs with a more positive ζ potential. The scanning electron microscopy images indicated that the morphological structure of the filler hardly changed during the preflocculation process. The effects of the preflocculation on the filler retention and paper properties were also investigated. The results show that the handsheets filled with preflocculated LM had better hydrophobicity and strength properties compared to handsheets filled with unpreflocculated LM, especially for H‐CPAM‐preflocculated LM. The paper formation was also improved, and the optical properties nearly remained the same. In addition, the LM preflocculated with H‐CPAM had the highest filler retention. At a filler loading of 30%, the filler retention of the H‐CPAM‐preflocculated LM was higher than 86; it was less than 82.5% in other cases. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41640. 相似文献
10.
《Current Opinion in Solid State & Materials Science》2019,23(4):100764
Extensive research has been directed towards the reinvention of paper for advanced applications. Nanocellulose-based films, a novel class of specialty paper primarily made of nanocellulose, demonstrate an ideal combination of sustainability and enhanced or novel properties. Enormous efforts have been devoted to enhancing these intrinsic properties and/or creating novel functions to expedite and expand the use of these materials in high-end fields such as touchscreen, solar cells, and nanogenerators. We review state-of-the-art advances in nanocellulose-based films and their utilization in several emerging and promising fields. We begin with an introduction of four types of nanocellulose-based films distinguished by their functional material loads (e.g., synthetic macromolecular polymers, 0D, 1D, and 2D nanomaterials), which involves their manufacturing techniques, structure design, properties, novel functions, and underlying principles. Additionally, we summarize the value-added applications of nanocellulose-based films in flexible electronics, energy converting or harvesting devices, and water treatment. Finally, we provide a critical viewpoint on the remaining challenges and future opportunities in this field. 相似文献