| 2 | 含液晶成分的掺杂共聚物和胆甾醇基棕榈酸盐(或酯)掺合物(英文)显示文摘Physical blends containing macromolecular compounds and low molecular weight liquid crystals (LCs) have important applications. LCs are used as reinforcements for amorphous polymers or in display devices. The addition of LCs to amorphous polymers determines improvements in the mechanical properties of polymeric composites. Due to their mechanical anisotropy, which results from molecular alignment, the LC molecules may orient themselves in the shear field of a processing operation. Upon cooling, this orientation may impart to the composites some improvements in the mechanical properties similar with that found with fibrous reinforcements, but with the advantage that the additive acts also as a plasticizer. The glass transition temperature and the viscosity of the blend are lower than those of the starting polymer. | Maria-Cristina Popescu Cornelia Vasile Daniela Filip Doina Macocinschi Gh. Singurel | 2005 | 光散射学报2005，17，3： | 0 |
| 3 | 老建筑里的家——布拉格住宅改造显示文摘坐落位置》捷克布拉格Tova/rni,Holesvovice面积》118 m2伏尔塔瓦河将布拉格一分为二,霍拉舍维采区位于伏尔塔瓦河的北面,这里到处都是老房子,成片的历史街区构成了丰富多彩的建筑景观。作为世界文化遗产城市,在老建筑中居住是多数布拉格人的生活模式。在霍拉舍维采一幢20世纪20年代的老宅中,精彩的建筑重生正在继续。由于家庭规模的不断扩大,对于更大居住空间的需求也随着增加;SOHO的兴起,使得家变成了移动的办公室和创意空间。 | Daniela Poluběvdovová 宫德坚 蒲仪军 Filip Slapal | 2016 | 家居主张2016，0，3： | 0 |
| 4 | The Igarapé Weir decelerated transport of contaminated sediment in the Paraopeba River after the failure of the B1 tailings dam(Brumadinho)显示文摘The B1 dam of Corrego do Feijao Mine,owned by Vale,S.A.mining company and located on the Ferro-Carvao stream,collapsed and injected 2.8 Mm^(3)of clayey,silty,and sandy iron-and manganese-rich tailings into the Paraopeba River(Minas Gerais state,Brazil).The accident occurred on 25 January 2019 and the tailings have been co-transported with coarser natural sediment since then,being partly trapped in the Igarape Weir reservoir located on the Paraopeba River nearly 45 km downstream the injection point.The general purpose of the current study was to model suspended sediment transport in the vicinity of the Igarape Weir aiming to assess the concomitant barrier effect imposed by this structure.Specifically,the spatial distributions of suspended clay,silt,and very fine-grained sand fractions(CSS)of sediment were mapped around the Igarape Weir under low-flow(16 m^(3)/s)and high-flow(5 to 10,000 years return period stream discharge;699e2,699 m^(3)/s)regimes,using RiverFlow2D as the modelling tool.The concentrations of the various grain materials in the upstream and downstream sectors were quantified linking the barrier effect to concentration reductions in the direction of stream flow.It was also a study goal to calculate differences of iron and manganese concentrations in the sediment+tailings mixtures along the Paraopeba River.The study results showed reductions in the CSS between 6.6%and 18%,from upstream to downstream of the Igarape Weir,related with backwater effects,free and sub-merged hydraulic jumps,bank sedimentation in periods of high flow,and streambed sedimentation controlled by channel sinuosity and tailings density.These reductions were accompanied by drops in the concentrations of iron and manganese present in the clay and silt fractions,which varied between 6%and 42%under low flows and between 16%and 44%under high flows.Bank sedimentation was viewed as a potential threat to the riparian vegetation in the long-term.Dredging is the potentially most effective mitigation measure to help lead the Paraopeba River to a pre-rupture condition.The retention of sediment+tailings transported in suspension is less effective than the trapping of bedload sediment+tailings behind the Igarape weir.The efficacy of sediment trapping is expected to be larger for natural sediment because it is much coarser than the tailings.In that context,the simulations revealed for the low-flow period that 33.6%of the sediment deposition comprised suspended transport of natural sediment(thus,was comprised 66.4%of bedload transport),this proportion rose to 86.9%for mixtures of natural sediment+tailings,a result that did not differ much for the high-flow periods. | Daniela Patrícia Salgado Terencio Fernando Antonio Leal Pacheco Renato Farias do Valle Junior Mayte Maria Abreu Pires de Melo Silva Teresa Cristina Tarle Pissarra Marília Carvalho de Melo Carlos Alberto Valera Luís Filipe Sanches Fernandes | 2023 | International Journal of Sediment Research2023，38，5： | 0 |
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