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91.
92.
《Calphad》2020
In this study, the Ga–Te binary system was reassessed by means of the CALPHAD method using a modified lattice stability parameter for Te as well as experimental data for this binary system. The two-sublattice ionic solution model was applied for the liquid phase, and the intermediate phases were described by the sublattice model. A set of self-consistent thermodynamic parameters was optimized for all the phases in the Ga–Te binary system, which reproduced the phase diagram and the thermodynamic properties well. Using the reevaluated Ga–Te system, previously assessed Ga–Se system, and modified Se–Te system, a critical evaluation of the Ga–Se–Te ternary system was performed. The calculated vertical sections, isothermal sections, and liquidus projection agreed reasonably well with the experimental data. Immiscibility in the liquid phase was observed, and the origin of this behavior is discussed from a thermodynamic perspective. 相似文献
93.
Patterned photonic crystals with structural colors on textile substrates have attracted a special attention due to the great advantages in application, which currently become a research hot-spot. This study utilized an ink-jet printing technology to prepare high-quality photonic crystal patterns with structural colors on polyester substrates. The self-assembly temperature of poly(styrene-N-methylol acrylamide) (P(St-NMA)) microspheres set to construct photonic crystals were deeply optimized. Moreover, the structural colors of prepared photonic crystal patterns were characterized and evaluated. When the mass fraction of P(St-NMA) microspheres was 1.0 wt.%, the pH value ranged from 5 to 7, and the surface tension was in the range of 63.79 to 71.20 mN/m, inks could present the best print performance. At 60 °C, prepared P(St-NMA) microsphere inks were good for printing to obtain patterned photonic crystals with regular arrangement and beautiful structural colors. Specifically, photonic crystals with different colors could be constructed by regulating the diameter of microspheres in inks, and prepared structural colors exhibited distinct iridescent phenomenon. The present results could provide a theoretical basis for the industrial realization of patterned photonic crystals by ink-jet printing technology. 相似文献
94.
Anna Sib Tobias M. Milzarek Alexander Herrmann Dr. Lila Oubraham Jonas I. Müller Prof. Dr. Andreas Pichlmair Prof. Dr. Ruth Brack-Werner Prof. Dr. Tobias A. M. Gulder 《Chembiochem : a European journal of chemical biology》2020,21(4):492-495
Sorbicillinoids are fungal polyketides characterized by highly complex and diverse molecular structures, with considerable stereochemical intricacy combined with a high degree of oxygenation. Many sorbicillinoids possess promising biological activities. An interesting member of this natural product family is sorbicatechol A, which is reported to have antiviral activity, particularly against influenza A virus (H1N1). Through a straightforward, one-pot chemoenzymatic approach with recently developed oxidoreductase SorbC, the characteristic bicyclo[2.2.2]octane core of sorbicatechol is structurally diversified by variation of its natural 2-methoxyphenol substituent. This facilitates the preparation of a focused library of structural analogues bearing substituted aromatic systems, alkanes, heterocycles, and ethers. Fast access to this structural diversity provides an opportunity to explore the antiviral potential of the sorbicatechol family. 相似文献
95.
Marta Gabasa Marselina Arshakyan Alejandro Llorente Lourdes Chuli-Peris Irina Pavelescu Antoni Xaubet Javier Pereda Jordi Alcaraz 《International journal of molecular sciences》2020,21(22)
Pro-inflammatory cytokines like interleukin-1β (IL-1β) are upregulated during early responses to tissue damage and are expected to transiently compromise the mechanical microenvironment. Fibroblasts are key regulators of tissue mechanics in the lungs and other organs. However, the effects of IL-1β on fibroblast mechanics and functions remain unclear. Here we treated human pulmonary fibroblasts from control donors with IL-1β and used Atomic Force Microscopy to unveil that IL-1β significantly reduces the stiffness of fibroblasts concomitantly with a downregulation of filamentous actin (F-actin) and alpha-smooth muscle (α-SMA). Likewise, COL1A1 mRNA was reduced, whereas that of collagenases MMP1 and MMP2 were upregulated, favoring a reduction of type-I collagen. These mechanobiology changes were functionally associated with reduced proliferation and enhanced migration upon IL-1β stimulation, which could facilitate lung repair by drawing fibroblasts to sites of tissue damage. Our observations reveal that IL-1β may reduce local tissue rigidity by acting both intracellularly and extracellularly through the downregulation of fibroblast contractility and type I collagen deposition, respectively. These IL-1β-dependent mechanical effects may enhance lung repair further by locally increasing pulmonary tissue compliance to preserve normal lung distension and function. Moreover, our results support that IL-1β provides innate anti-fibrotic protection that may be relevant during the early stages of lung repair. 相似文献
96.
以Ti6Al4V球形粉末为原料,利用激光选区熔化成形方法制备了Ti6Al4V合金试样,采用光学显微镜、扫描电镜及力学性能测试等手段,研究了退火工艺对Ti6Al4V合金室温力学性能及组织的影响规律。结果表明: SLM成形沉积态Ti6Al4V合金室温抗拉强度超过1200 MPa,而平均断后伸长率仅为4.0%;在650 ℃下进行真空退火处理,合金的抗拉强度仍保持在1200 MPa左右,规定塑性延伸强度Rp0.2高于1150 MPa,但试样的断后伸长率<10%;而在750及800 ℃下进行真空退火处理,合金试样的抗拉强度降至1100 MPa左右,规定塑性延伸强度高于1050 MPa,伸长率达到甚至超过10%,材料的综合强韧性得到明显提升。随着真空退火加热温度和保温时间的增加,SLM成形Ti6Al4V合金原始β晶界逐渐变模糊,晶粒趋向于等轴化。与此同时,快速冷却转变的α′针状马氏体未出现明显地粗化。 相似文献
97.
Dr. Dimitra T. Pournara Anna Durner Dr. Eftichia Kritsi Alexios Papakostas Dr. Panagiotis Zoumpoulakis Prof. Dr. Annette Nicke Dr. Maria Koufaki 《ChemMedChem》2020,15(24):2530-2543
The P2X7 receptor is a promising target for the treatment of various diseases due to its significant role in inflammation and immune cell signaling. This work describes the design, synthesis, and in vitro evaluation of a series of novel derivatives bearing diverse scaffolds as potent P2X7 antagonists. Our approach was based on structural modifications of reported (adamantan-1-yl)methylbenzamides able to inhibit the receptor activation. The adamantane moieties and the amide bond were replaced, and the replacements were evaluated by a ligand-based pharmacophore model. The antagonistic potency of the synthesized analogues was assessed by two-electrode voltage clamp experiments, using Xenopus laevis oocytes that express the human P2X7 receptor. SAR studies suggested that the replacement of the adamantane ring by an aryl-cyclohexyl moiety afforded the most potent antagonists against the activation of the P2X7 cation channel, with analogue 2-chloro-N-[1-(3-(nitrooxymethyl)phenyl)cyclohexyl)methyl]benzamide ( 56 ) exhibiting the best potency with an IC50 value of 0.39 μM. 相似文献
98.
99.
以井下供电监控及防越级跳闸运用为对象开展探究。在分析矿井供电系统运行中现存主要问题的基础上,对供电监控与防越级跳闸系统整体应用的积极意义进行了分析和总结,希望能够让更多矿井技术人员了解供电监控及防越级跳闸系统的优越性,为其在矿井中的广泛推广普及提供便利,为煤矿行业更加高效地发展提供帮助。 相似文献
100.