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AbstractA novel modification for Green and Naghdi thermoelasticity model of type III is proposed in this article. This model is joined to other ones to treat a thermoelastic wave propagation problem in an annular disk. The closed-form solution of thermoelastic analysis of the annular disks has been presented to deduce temperature, radial displacement, dilatation and stresses. Results are illustrated and reported to compare the simple Green–Naghdi II and III and their modified single-, dual- and three-phase-lag models. Concluding remarks are added. 相似文献
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全球经验表明,疫情会对经济社会产生负面影响。此次中国武汉市新型冠状病毒疫情爆发的时间节点、波及的领域范围,以及为应对疫情釆取的相关部署安排,既考验着电力行业保障电力安全可靠供应的能力,也会直接或间接通过电力供求形势变化影响电力企业的生产运行。结合疫情因素和近年来中国经济运行中电力供求变化特点,本文认为疫情将会降低工业和商业用电负荷,医疗机构新增用电和居民生活用电将会显著增长,但鉴于工商业用电比重较高的事实,全社会用电量同期同比增速将明显放缓。考虑到近年来用电增速放缓的经验事实,此次疫情或将放大电力行业积聚的矛盾和困难,因此为发挥市场在电力资源配置中的决定性作用而加快推进电力体制改革和全国统一电力市场建设愈发重要与迫切。 相似文献
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《International Journal of Hydrogen Energy》2020,45(27):13975-13984
An intervening barrier for photocatalytic water decomposition and pollutant degradation is the frustratingly quick recombination of e− - h+ pairs. Delicate design of heterojunction photocatalysts by coupling the semiconductors at nanoscale with well-matched geometrical and electronic alignments is an effective strategy to ameliorate the charge separation. Here a facile and environment-friendly l-cysteine-assisted hydrothermal process under weakly alkaline conditions is demonstrated for the first time to fabricate ZnIn2S4/In(OH)3 hollow microspheres with intimate contact, which are verified by XRD, SEM, (HR)TEM, XPS, N2 adsorption-desorption, UV–Vis DRS and photoluminescence spectra. ZnIn2S4/In(OH)3 heterostructure (L-cys/Zn2+ = 4, molar ratio) with a band-gap of 2.50 eV, demonstrates the best photocatalytic performance for water reduction and MB degradation under visible light, outperforming its counterparts (In(OH)3 and ZnIn2S4). The excellent activity of ZnIn2S4/In(OH)3 heterostructure arises from the intercrossed band-edge positions as well as the unique hollow structure with large surface area and wide pore-size distribution, which are beneficial for the efficient charge migration from bulk to surface as well as at the interface between ZnIn2S4 and In(OH)3. This work provides an efficient and eco-friendly strategy for one-pot synthesis of heterostructured composites with intimate contact for photocatalytic application. 相似文献
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Dr. Blijke S. Kroezen Gabriele Conti Benedetta Girardi Dr. Jonathan Cramer Dr. Xiaohua Jiang Dr. Said Rabbani Jennifer Müller Maja Kokot Enrico Luisoni Prof. Daniel Ricklin Dr. Oliver Schwardt Prof. Beat Ernst 《ChemMedChem》2020,15(18):1706-1719
Siglecs are members of the immunoglobulin gene family containing sialic acid binding N-terminal domains. Among them, Siglec-8 is expressed on various cell types of the immune system such as eosinophils, mast cells and weakly on basophils. Cross-linking of Siglec-8 with monoclonal antibodies triggers apoptosis in eosinophils and inhibits degranulation of mast cells, making Siglec-8 a promising target for the treatment of eosinophil- and mast cell-associated diseases such as asthma. The tetrasaccharide 6’-sulfo-sialyl Lewisx has been identified as a specific Siglec-8 ligand in glycan array screening. Here, we describe an extended study enlightening the pharmacophores of 6’-sulfo-sialyl Lewisx and the successful development of a high-affinity mimetic. Retaining the neuraminic acid core, the introduction of a carbocyclic mimetic of the Gal moiety and a sulfonamide substituent in the 9-position gave a 20-fold improved binding affinity. Finally, the residence time, which usually is the Achilles tendon of carbohydrate/lectin interactions, could be improved. 相似文献
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Two studies were conducted in order to investigate the influence of teaware on consumers’ subjective ratings of, and taste expectations concerning, one of the world’s most popular beverages, namely tea. In Study 1, 100 Chinese participants and 100 participants from the USA viewed online photographs of Chinese brand and British brand green tea presented in either Chinese or British tea sets. The participants then rated their feelings about, taste expectations concerning, and willingness-to-pay for, each cup of tea. In Study 2, 65 Chinese participants also viewed these photos with either a high or low price label for each cup of tea. The results of both studies consistently revealed that the teaware influenced Chinese participants’ bitterness and astringency ratings concerning their tea expectations; whereas no such effects were found for the USA participants. Moreover, the teaware also influenced Chinese participants’ pleasantness ratings of tea when no price information was provided, but not when price information was presented. Collectively, these findings highlight the influence of the visual appearance of the receptacle on the subjective ratings of, and taste expectations concerning, tea. These results also compare the influence of product-extrinsic and contextual cues on consumers’ taste expectations. 相似文献
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G. Seeta Rama Raju E. Pavitra L. Krishna Bharat Gattupalli Manikya Rao Tae-Joon Jeon Yun Suk Huh Young-Kyu Han 《Ceramics International》2018,44(12):13852-13857
Upconversion Sr2(Gd.98-xEr.02Ybx)8Si6O26 (SGSO:2Er3+/xYb3+) phosphor materials were synthesized using a citrate sol-gel process. X-ray diffraction patterns confirmed their hexagonal structure. Field emission scanning electron microscopy images of SGSO:2Er3+/xYb3+ phosphors depicted submicron particles. The enhanced upconversion luminescence properties of SGSO:2Er3+/xYb3+ phosphors were analysed as a function of Yb3+ ion concentration and laser power. The energy transfer induced enhanced emission of the Er3+/ Yb3+ ions co-doped SGSO phosphors was ascribed to multi-phonon relaxation. The calculated chromaticity coordinates of the SGSO:2Er3+/xYb3+ phosphors showed emissions could be tuned by changing Yb3+ ion concentration. Optimized sample exhibited the chromaticity coordinate values near to the ultra-high definition television standard green emission coordinates. 相似文献