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31.
Francesco Morena Chiara Argentati Michelina Soccio Ilaria Bicchi Francesca Luzi Luigi Torre Andrea Munari Carla Emiliani Matteo Gigli Nadia Lotti Ilaria Armentano Sabata Martino 《International journal of molecular sciences》2020,21(23)
Herein, we present poly(butylene 1,4-cyclohexanedicarboxylate) (PBCE) films characterized by an unpatterned microstructure and a specific hydrophobicity, capable of boosting a drastic cytoskeleton architecture remodeling, culminating with the neuronal-like differentiation of human bone marrow-mesenchymal stem cells (hBM-MSCs). We have used two different filming procedures to prepare the films, solvent casting (PBCE) and compression-moulding (PBCE*). PBCE film had a rough and porous surface with spherulite-like aggregations (Ø = 10–20 μm) and was characterized by a water contact angle = 100°. PBCE* showed a smooth and continuous surface without voids and visible spherulite-like aggregations and was more hydrophobic (WCA = 110°). Both surface characteristics were modulated through the copolymerization of different amounts of ether-oxygen-containing co-units into PBCE chemical structure. We showed that only the surface characteristics of PBCE-solvent-casted films steered hBM-MSCs toward a neuronal-like differentiation. hBM-MSCs lost their canonical mesenchymal morphology, acquired a neuronal polarized shape with a long cell protrusion (≥150 μm), expressed neuron-specific class III β-tubulin and microtubule-associated protein 2 neuronal markers, while nestin, a marker of uncommitted stem cells, was drastically silenced. These events were observed as early as 2-days after cell seeding. Of note, the phenomenon was totally absent on PBCE* film, as hBM-MSCs maintained the mesenchymal shape and behavior and did not express neuronal/glial markers. 相似文献
32.
研究了添加锥栗、马铃薯与绿豆回生抗性淀粉(RS3)对米淀粉的冻融稳定性与流变学性质的影响。结果表明:添加锥栗、马铃薯与绿豆RS3都能显著提高米淀粉凝胶的持水率,且冻融超过3次后,其影响的差别越来越显著。随着冻融次数增多,米淀粉凝胶中不易流动水明显降低、自由水显著增加;当冻融次数相同时,添加RS3可使米淀粉凝胶中不易流动水明显增多而自由水显著减少。添加锥栗、马铃薯和绿豆RS3后,米淀粉糊的黏性模量明显增加,而弹性模量的增加更加显著。在相同剪切速率下,添加锥栗、马铃薯和绿豆RS3可以使米淀粉糊的抗剪切强度大大增强。添加相同质量浓度的锥栗、马铃薯和绿豆RS3后,米淀粉糊的稠度系数都大大升高、流体指数和滞后环面积显著减小。 相似文献
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ABSTRACTMedium-Mn steels are energetically investigated as a candidate of the third generation advanced high strength steels (AHSSs). However, their phase transformation and microstructaure evolution during various heat treatments and thermomechanical processing are still unclear. The present study first confirmed the kinetics of static phase transformation behaviour in a 3Mn-0.1C medium-Mn steel. Hot compression tests were also carried out to investigate the influence of high-temperature deformation of austenite on subsequent microstructure evolution. It was found that static ferrite transformation was quite slow in this steel, but ferrite transformation was greatly accelerated by the hot deformation in austenite and ferrite two-phase regions. Characteristic dual-phase microstructures composed of martensite and fine-grained ferrite were obtained, which exhibited superior mechanical properties.This paper is part of a Thematic Issue on Medium Manganese Steels. 相似文献
35.
Hiromi Nakano 《Advanced Powder Technology》2019,30(10):2003-2013
In the Li2O–M2O5–TiO2 (M = Nb or Ta) system, Li1+x-yM1-x-3yTix+4yO3 (LMT) forms with a superstructure known as the M-phase, in which the periodical intergrowth layers are inserted in a matrix having a trigonal structure of LiMO3. We have been investigating this unique material focusing on its crystal structure, photoluminescence, and electrical properties.First, the formation area of the superstructure was compared between Nb- and Ta- systems and the difference was accurately analyzed.Second, to apply this unique material as a host material of phosphor, we synthesized new phosphors with various emission colors. Red phosphor, having a high PL intensity with an internal quantum efficiency of 98%, was successfully synthesized and used as a host material of the solid solution for the Ta system. Its high value was the result of the large centroid-to-cation distance of the Eu3+ position in the [(Li, Eu)O12] polyhedral.Further still, toward application of the unique qualities of an electro-ceramic, we successfully fabricated oriented balk ceramics for the Nb system by slip casting in a strong magnetic field of 12 T. As a result, anisotropic electric properties were found along the c-axis, which were caused by the superstructure. We first clarified the mechanism showing that the anisotropic Qf value was due to anisotropic electron conductivity and anisotropic bonding strength within the superstructure. 相似文献
36.
钢厂煤气脱硫工序排放的废脱硫剂是一种难以利用的有害固体废弃物,含一定量的铁及较高的钙和硫等元素。对废脱硫剂配入铁矿粉中进行了烧结杯的试验研究,结果表明,当废脱硫剂配比超过01%后,随着废脱硫剂配比的升高,烧结矿转鼓强度下降,利用系数下降,烧结烟气中SO2与NOx浓度增加,烧结矿的还原度有所下降,但烧结矿的低温还原粉化性能有所改善。烧结矿的矿相研究发现,废脱硫剂配比偏大时,磁铁矿体积分数增大,铁酸钙体积分数减少,并由针状结构向柱状、板状演变,烧结矿的气孔率上升。主要原因在于其粒度偏粗,含硫高,不利于成矿。当废脱硫剂粒度为-63mm及其配比控制在01%时,烧结矿的产量和质量有所改善,烟气中SO2、NOx较基准试验变化不大。工业试验表明,在烧结混匀矿中配入废脱硫剂配比小于012%时,烧结矿产量和质量没有明显变化,烧结烟气脱硫脱硝效果也没有受到影响。废脱硫剂掺入铁矿中进行烧结是一种资源化利用的有效方法,不仅解决了有害固体废弃物对环境的影响,而且使二次资源得到综合利用。 相似文献
37.
38.
Hydrolytic stability is an essential requirement for polyurethanes (PUs) that are used in highly humid and aqueous environments. In this study, hydrolysis-resistant PU elastomers (PUEs) are synthesized based on hydrophobic bio-based polyfarnesene diol (PFD), which contains unique “bottle brushes” structure (with long branched hydrocarbon side chains). The effect of hard segment (HS) content, ranging from 30 to 50%, on the morphology and properties of PUEs is investigated by Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, tensile, water absorption, and contact angle measurements. The results show that there are prominent phase separations in the synthesized PUEs. The PUEs show a three-stage degradation process and two Tg, one is at about −66 °C and the other 61 °C, which are related to the soft segment and HS, respectively. Water contact angles of PUEs increase from 98.6 to 105.2° with the increasing of PFD structural unit fraction. After being immersed in deionized water for 30 days, PUEs show no significant degradation of both tensile strength and elongation at break, and mass changes of all samples are less than 0.5%. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47673. 相似文献
39.
《Ceramics International》2019,45(15):18876-18886
Red-emitting Sr0.8Ca0.19AlSiN3:0.01Eu2+ phosphor with halide fluxes for use in the production of white light-emitting diodes (white LEDs) with high-colour rendering indices (CRIs) was prepared through the high-temperature solid-state method. Fluoride (NaF, SrF2, BaF2, CaF2, AlF3·3H2O and CeF3), chloride (NH4Cl, BaCl2, MgCl2, NaCl and LiCl) and composite fluxes (NaF + SrF2, SrF2+NH4Cl and NaF + NH4Cl) were applied in the phosphors. NaF, SrF2, NH4Cl and NaF + SrF2 fluxes had prominent effects on the characteristics of Sr0.8Ca0.19AlSiN3:0.01Eu2+ phosphors. Sr0.8Ca0.19AlSiN3:0.01Eu2+ phosphors with various powder morphologies can be obtained through the addition of fluxes, which are conducive for phosphor formation. The powder morphologies of phosphors incorporated with NaF + SrF2 were preferable to those of powders incorporated with other fluxes. This result indicated that the incorporation of NaF + SrF2 into Sr0.8Ca0.19AlSiN3:0.01Eu2+ yielded phosphors with high luminescent intensity and quantum efficiency, excellent thermal stability, narrow full widths at half-maximum (FWHM, 75.2 nm), uniform rod-like morphologies with large particle sizes (D50 = 16.99 μm) and good particle dispersion. White LEDs with high CRIs were obtained by combining prepared phosphors (NaF + SrF2 additive) with the commercial green-emitting phosphors Y3(Al,Ga)5O12:Ce3+ and (Sr,Ba)2SiO4:Eu2+. White LEDs with Y3(Al,Ga)5O12:Ce3+ and (Sr,Ba)2SiO4:Eu2+ phosphors had correlated colour temperatures (CCTs) of 3064 and 3023 K, respectively, and CRIs of 81.8 and 92.4, respectively. Therefore, NaF + SrF2 can be used as a favourable flux for the production of Sr0.8Ca0.19AlSiN3:0.01Eu2+. 相似文献
40.