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[点击科学]2019年6月点击科学

陶 陶 编译

2019-06/总第279期

阅读数9

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2019-04-26

长期以来,化学家们一直试图理解与共价键形成相关的原子级别的运动,以及能量耗散的途径。当一个氢原子(白色)与石墨烯(黑色)碰撞时,可能会形成一个短暂的碳氢键。由于再次杂化,相邻碳原子的排斥作用会导致能量通过声波(白色圆环)快速转移,从而稳定了这个键。

Chemists have long sought to understand the atomic-scale motion and energy dissipation pathways associated with covalent bond formation. When a hydrogen atom (white) collides with graphene (black), a transient carbon-hydrogen bond may form. As a result of rehybridization, repulsion of neighboring carbon atoms leads to rapid energy transfer through sonic waves (white rings), which stabilize the bond.

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2019-05-03

封面图上展示的是3D打印多血管水凝胶的景深合成照片,其中包含一个仿生肺泡囊(底部宽度约为4.5毫米),周围环绕着仿制远端肺结构的血管网络(直径≥0.3毫米)。这个通透的膨胀气囊可以为人体红细胞提供氧气,红细胞通过鞘状脉管系统流动。材料创新为我们提供了一种建立和研究工程组织内的多血管拓扑结构的方法。

Focus-stacked photograph of a 3D printed multivascular hydrogel containing a bioinspired alveolar air sac (width at bottom: 〜4.5 mm) surrounded by a network of blood vessels (diameter: ≥0.3 mm) mimicking distal lung architecture. The ventilated, distending air sac provides oxygen to human red blood cells that flow through the ensheathing vasculature. A materials innovation provides a means to build and study multivascular topology within engineered tissues.

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2019-05-10

封面图展示的是鞭尾鱼,它是深海鱼类的一种。这种鱼已经扩大了其视紫红质基因的范围,从而最大限度地提高视觉灵敏度,并可能实现色彩检测。在深海中,多色的生物发光取代了表面照明成为主要的光源。许多生活在深海的鱼类已经进化出了一套视觉系统,用来识别生物发光信号,以及在黑暗中感知色彩。

The tube-eye (Stylephorus chordatus) is one of several species of deep-sea fish to have expanded its repertoire of rhodopsin genes to maximize visual sensitivity and, possibly, color detection. In the deep sea, multicolored bioluminescence replaces surface illumination as the main source of light. Many fishes that reside at great depths have evolved a visual system for recognizing bioluminescent signals and perceiving color in the dark.

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2019-05-17

封面上展示的是新视野号宇宙飞船在2019年1月1日高速飞越期间观测到的柯伊伯带天体2014 MU69。据观测,MU69是一个双裂片相接双星,也就是说它以前是分开的天体,现在慢慢地融合在一起形成了这个相接双星。封面这张增强色彩的图像显示了2个相同红色的裂瓣,以及在接触点的位置有更明亮的物质。

The Kuiper Belt object 2014 MU69, as observed by the New Horizons spacecraft during a high-speed flyby on 1 January 2019. MU69 is found to be a two-lobed contact binary—formerly separate objects that have gently merged together. This enhanced-color image shows the uniform red color of both lobes, with brighter material at the contact point.

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