Stable sodium metal anode enhanced by advanced electrolytes with SbF3 additive

The practical application of sodium metal batteries (SMBs) is hampered due to the inferior interfacial stability between Na metal and conventional electrolytes....     

磁性PSF／CoFe2O4杂化超滤膜的研究

一种新的磁性纳米粒子一铁酸钴(CoFe2O4)被引入聚砜膜,采用相转化法制备聚砜/铁酸钴(PSF/CoFe2O4)杂化超滤膜,并通过磁场诱导超滤实验,差示扫描量热仪(DSC)、磁强计(MPMS)、扫描电镜(SEM)等测试手段考察了膜的性能和结构.结果表明:磁场对聚砜/铁酸钴复合膜的截留率有调节作用,该杂化膜磁滞效应明显;膜中形成有机大分子网络(PSF)与无机纳米粒子(CoFe2O4)分散增强型结构;与未添加CoFe2O4的PSF膜相比,复合膜的玻璃化温度升高.     

Polyprotein of GB1 is an ideal artificial elastomeric protein

Naturally occurring elastomeric proteins function as molecular springs in their biological settings and show mechanical properties that underlie the elasticity of natural adhesives, cell adhesion proteins and muscle proteins. Constantly subject to repeated stretching-relaxation cycles, many elastomeric proteins demonstrate remarkable consistency and reliability in their mechanical performance. Such properties had hitherto been observed only in naturally evolved elastomeric proteins. Here we use single-molecule atomic force microscopy techniques to demonstrate that an artificial polyprotein made of tandem repeats of non-mechanical protein GB1 has mechanical properties that are comparable or superior to those of known elastomeric proteins. In addition to its mechanical stability, we show that GB1 polyprotein shows a unique combination of mechanical features, including the fastest folding kinetics measured so far for a tethered protein, high folding fidelity, low mechanical fatigue during repeated stretching-relaxation cycles and ability to fold against residual forces. These fine features make GB1 polyprotein an ideal artificial protein-based molecular spring that could function in a challenging working environment requiring repeated stretching-relaxation. This study represents a key step towards engineering artificial molecular springs with tailored nanomechanical properties for bottom-up construction of new devices and materials.     

Multi‐modal brain tumor image segmentation based on SDAE

Accurate tumor segmentation has the ability to provide doctors with a basis for surgical planning. Moreover, brain tumor segmentation needs to extract different tumor tissues (Edema, tumor, tumor enhancement, and necrosis) from normal tissues which is a big challenge because tumor structures vary considerably across patients in terms of size, extension, and localization. In this article, we evaluate a fully automated method for segmenting brain tumor images from multi‐modal magnetic resonance imaging volumes based on stacked de‐noising auto‐encoders (SDAEs). Specially, we adopted multi‐modality information from T1, T1c, T2, and Flair images, respectively. We extracted gray level patches from different modalities as the input of the SDAE. After trained by the SDAE, the raw network parameters will be obtained, which are adopted as a parameter of the feed forward neural network for classification. A simple post‐processing is implemented by threshold segmentation method to generate a mask to get the final segmentation result. By evaluating the proposed method on the BRATS 2015, it can be proven that our method obtains the better performance than other state‐of‐the‐art counterpart methods. And a preliminary dice score of 0.86 for whole tumor segmentation has been achieved.     

Shape‐Controlled Synthesis of High‐Quality Cu7S4 Nanocrystals for Efficient Light‐Induced Water Evaporation

Copper sulfides (Cu_2–xS), are a novel kind of photothermal material exhibiting significant photothermal conversion efficiency, making them very attractive in various energy conversion related devices. Preparing high quality uniform Cu_2‐xS nanocrystals (NCs) is a top priority for further energy‐and sustainability relevant nanodevices. Here, a shape‐controlled high quality Cu₇S₄ NCs synthesis strategy is reported using sulfur in 1‐octadecene as precursor by varying the heating temperature, as well as its forming mechanism. The performance of the Cu₇S₄ NCs is further explored for light‐driven water evaporation without the need of heating the bulk liquid to the boiling point, and the results suggest that as‐synthesized highly monodisperse NCs perform higher evaporation rate than polydisperse NCs under the identical morphology. Furthermore, disk‐like NCs exhibit higher water evaporation rate than spherical NCs. The water evaporation rate can be further enhanced by assembling the organic phase Cu₇S₄ NCs into a dense film on the aqueous solution surface. The maximum photothermal conversion efficiency is as high as 77.1%.     

天然淀粉的热塑性加工及其力学性能

介绍了一种制备热塑性淀粉材料的加工方法，考察了两种不同增塑剂对淀粉加工工艺参数的影响，比较了所得材料的力学性能。     

氧离子能量对离子束辅助沉积Al2O3薄膜的结构及光学性能的影响

利用氧离子束辅助脉冲反应磁控溅射技术在聚酰亚胺基底上沉积Al2O3薄膜。这项技术在溅射高纯铝靶材的同时利用低能氧离子进行氧化来控制薄膜的化学配比。研究了薄膜沉积过程中离子束辅助的作用以及离子束放电电压对Al2O3薄膜的化学成分、结构、表面形貌、光学性能以及沉积速率的影响。结果发现,离子束放电电压对薄膜的化学成分具有显著影响,当电压增加到200 V,薄膜已基本达到完全化学计量比且薄膜为非晶结构;薄膜表面粗糙度随着离子束放电电压的增加而减小,当电压达到300V时,薄膜具有最小的表面粗糙度;通过对Al2O3薄膜透射谱的测量,分析薄膜的光学特性,获得了薄膜的光学常数随离子束放电电压的变化规律,发现氧离子束辅助沉积的薄膜具有较高的折射系数和较低的消光系数;另外,薄膜的沉积速率在电压增加到300V时达到最大值70 nm/min,是未采用离子束辅助时沉积速率的5倍。     

PC/CF共混体系的加工流变性能与力学性能

利用微量双螺杆挤出机(Hakke MiniLabⅡ,Rheomex CTW5),通过熔融共混挤出注塑的方法,在聚碳酸酯(PC)中添加炭纤维(CF)进行复合增强。实验对共混物加工过程中的流变行为进行了分析,研究了炭纤维含量对复合材料力学性能的影响,探讨了其黏度与力学性能变化的机理,由扫描电子显微镜观测拉伸及冲击破坏的试样断面形态。结果表明,当CF质量分数为2%时,复合材料非牛顿指数n值最小,假塑性最强,易于加工;同时,复合材料的综合力学性能也最为优异。扫描电镜照片显示,拉伸破坏的主要方式为界面脱胶,而冲击破坏的主要方式为纤维断裂。