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1.
立面和立面设计是建筑的基本要素,媒体立面是立面设计相对较新的分支领域。文章概述了媒体立面的设计与研究过程,并以六个项目为例介绍立面设计涉及的元素与子元素如何与通信技术相互结合。 相似文献
2.
Mohamed A.El-Nemr Ibrahim M.A.Ismail Nabil M.Abdelmonem Ahmed El Nemr Safaa Ragab 《中国化学工程学报》2021,36(8):199-222
Watermelon peel residues were used to produce a new biochar by dehydration method. The new biochar has undergone two methods of chemical modification and the effect of this chemical modification on its ability to adsorb Cr(VI) ions from aqueous solution has been investigated. Three biochars, Melon-B, Melon-BO-NH_2 and Melon-BO-TETA, were made from watermelon peel via dehydration with 50% sulfuric acid to give Melon-B followed by oxidation with ozone and amination using ammonium hydroxide to give Melon-BO-NH_2 or Triethylenetetramine(TETA) to give Melon-BO-TETA. The prepared biochars were characterized by BET, BJH,SEM, FT-IR, TGA, DSC and EDAX analyses. The highest removal percentage of Cr(VI) ions was 69% for Melon-B,98% for Melon-BO-NH_2 and 99% for Melon-BO-TETA biochars of 100 mg·L~(-1) Cr(VI) ions initial concentration and 1.0 g·L~(-1) adsorbents dose. The unmodified biochar(Melon-B) and modified biochars(Melon-BO-NH_2 and Melon-BO-TETA) had maximum adsorption capacities(Qm) of 72.46, 123.46, and 333.33 mg·g~(-1), respectively.The amination of biochar reduced the pore size of modified biochar, whereas the surface area was enhanced.The obtained data of isotherm models were tested using different error function equations. The Freundlich,Tempkin and Langmuir isotherm models were best fitted to the experimental data of Melon-B, Melon-BO-NH_2 and Melon-BO-TETA, respectively. The adsorption rate was primarily controlled by pseudo-second–order rate model. Conclusively, the functional groups interactions are important for adsorption mechanisms and expected to control the adsorption process. The adsorption for the Melon-B, Melon-BO-NH_2 and Melon-BO-TETA could be explained for acid–base interaction and hydrogen bonding interaction. 相似文献
3.
Pablo Salcedo-Abraira Sergio M.F.Vilela Artem A.Babaryk Maria Cabrero-Antonino Pedro Gregorio Fabrice Salles Sergio Navalon Hermenegildo Garcia Patricia Horcajada 《Nano Research》2021,14(2):450-457
A novel microporous two-dimensional(2D)Ni-based phosphonate metal-organic framework(MOF;denoted as IEF-13)has been successfully synthesized by a simple and green hydrothermal method and fully characterized using a combination of experimental and computational techniques.Structure resolution by single-crystal X-ray diffraction reveals that IEF-13 crystallizes in the triclinic space group Pi having bi-octahedra nickel nodes and a photo/electroactive tritopic phosphonate ligand.Remarkably,this material exhibits coordinatively unsaturated nickel(II)sites,free-P03H2and-P03H acidic groups,a C02accessible microporosity,and an exceptional thermal and chemical stability.Further,its in-deep optoelectronic characterization evidences a photoresponse suitable for photocatalysis.In this sense,the photocatalytic activity for challenging H2generation and overall water splitting in absence of any co-catalyst using UV-Vis irradiation and simulated sunlight has been evaluated,constituting the first report for a phosphonate-MOF photocatalyst.IEF-13 is able to produce up to 2,200 fimol of H2per gram using methanol as sacrificial agent,exhibiting stability,maintaining its crystal structure and allowing its recycling.Even more,170μmol of H2per gram were produced using IEF-13 as photocatalyst in the absence of any co-catalyst for the overall water splitting,being this reaction limited by the 02reduction.The present work opens new avenues for further optimization of the photocatalytic activity in this type of multifunctional materials. 相似文献
4.
水驱老油田进入开发后期,套管变形井不断增加,严重影响了厚油层的分层开采效果。针对套管变形井和套管补贴井,研发了小直径的堵水封隔器,胶筒的膨胀比达1.4~1.5,具有逐级解封、抗滑动能力强、耐压差高、适应套管直径范围大、有效期长、解封可靠等特点,耐压差20~30 MPa,配套小直径开关工具,实现多层卡封、多层开采。现场应用表明,外径105 mm的封隔器在178 mm套管内卡封,耐压差达到20 MPa;外径95 mm的封隔器在139.7 mm套管内卡封,耐压差达到30 MPa。 相似文献
5.
6.
Pratik P. BHATT Venkatesh K. R. KODUR Anuj M. SHAKYA Tarek ALKHRDAJI 《Frontiers of Structural and Civil Engineering》2021,15(1):177
This paper presents the results of fire resistance tests on carbon fiber-reinforced polymer (CFRP) strengthened concrete flexural members, i.e., T-beams and slabs. The strengthened members were protected with fire insulation and tested under the combined effects of thermal and structural loading. The variables considered in the tests include the applied load level, extent of strengthening, and thickness of the fire insulation applied to the beams and slabs. Furthermore, a previously developed numerical model was validated against the data generated from the fire tests; subsequently, it was utilized to undertake a case study. Results from fire tests and numerical studies indicate that owing to the protection provided by the fire insulation, the insulated CFRP-strengthened beams and slabs can withstand four and three hours of standard fire exposure, respectively, under service load conditions. The insulation layer impedes the temperature rise in the member; therefore, the CFRP–concrete composite action remains active for a longer duration and the steel reinforcement temperature remains below 400°C, which in turn enhances the capacity of the beams and slabs. 相似文献
7.
形状记忆合金由于其优良的超弹性和形状记忆效应而在医学上有着广泛的应用,其中由于NiTi形状记忆合金相较其它形状记忆合金具有更好的超弹性和生物相容性而得到了广泛的应用。但由于镍元素的毒性,使得开发一种生物相容性更好、无镍且具有良好力学性能的形状记忆合金成为必需。Ti-Mo-V-Nb-Al五元合金就是为此而开发的一种新型形状记忆合金。本研究用X射线衍射(XRD)、透射电子显微镜(TEM)和高分辨电子显微镜(HREM)研究了不同热处理条件对Ti-Mo-V-Nb-Al形状记忆合金微观结构的影响。 相似文献
8.
新年前夕 ,一项由安棚天然碱有限责任公司研制并应用、具有自主知识产权、一直备受国内外业内同行关注的天然碱制取纯碱技术 ,正式通过国家科技部委托内蒙古自治区科委组织的评审验收和技术鉴定。安棚天然碱有限责任公司是由内蒙古伊克昭化工集团、河南油田和河南省桐柏县三方以股份合作形式成立的现代化工企业。 1999年 ,原国家科委曾对天然碱制取低盐重质粒状纯碱技术、天然碱制纯碱工艺技术 (俗称倍半碱流程 )立项攻关。通过两年多的研究和应用 ,目前已成为日臻成熟的纯碱制取技术。参加技术鉴定和评审验收的专家们认为 :该项技术的研究… 相似文献
9.
硫酸厂主鼓风机的主要设计准则 总被引:1,自引:1,他引:0
论述现代硫酸厂主鼓风机设计时必须考虑的关键因素,通过实例讨论操作费用与投资之间的平衡关系以及对装置竞争力的影响。建议在硫酸厂严酷的操作条件下改进风机特性,提高耐磨性并采用维修友好的设计。 相似文献
10.