Protocells programmed through artificial reaction networks

As the smallest unit of life, cells attract interest due to their structural complexity and functional reliability. Protocells assembled by inanimate components are created as an artificial entity to mimic the structure and some essential properties of a natural cell, and artificial reaction networks are used to program the functions of protocells. Although the bottom-up construction of a protocell that can be considered truly ‘alive’ is still an ambitious goal, these man-made constructs with a certain degree of ‘liveness’ can offer effective tools to understand fundamental processes of cellular life, and have paved the new way for bionic applications. In this review, we highlight both the milestones and recent progress of protocells programmed by artificial reaction networks, including genetic circuits, enzyme-assisted non-genetic circuits, prebiotic mimicking reaction networks, and DNA dynamic circuits. Challenges and opportunities have also been discussed.

In this review, the milestones and recent progress of protocells programmed by various types of artificial reaction networks are highlighted.     

重过程促能力提升课堂实效——对"力的存在"案例反思

1背景问题 本学期笔者接触到七年级《科学》“力的存在”一课,在教学活动中教师致力于实现新课程提出的知识与技能、过程与方法、情感态度与价值观的三维教学目标;力图体现新课程改革所提倡的“自主、合作、探究”的学习方式,这都是值得肯定的．但同时也有一些问题引起我的一些思考：第一,课堂中启发性的提问可以激发学生的思维,课堂也活跃起来了,     

An extension of the Fiedler-Markham determinant inequality

We extend a determinant inequality of Fiedler and Markham [On a theorem of Everitt, Thompson, and de Pillis, Math Slovaca, 44 (1994), 441–444] to the class of matrices whose numerical range is contained in a sector. Moreover, some related results are also included.     

"强光一号"Al丝阵Z箍缩产生K层辐射实验研究

在"强光一号"加速器开展了Al丝阵Z箍缩产生K层辐射的实验研究,固定Al丝线径20 μm、丝阵直径12 mm,丝根数为8和12的负载获得K层产额分别为0.9 kJ/cm和1.1 kJ/cm,明显高于16和24根丝负载.辐射功率波形和时间分辨的X射线图像显示,低丝数负载存在拖尾质量引起的多次内爆现象.在60%-80%的内爆时间内,丝阵几乎停留在初始位置;主体内爆在随后的25-30 ns内完成,将部分等离子体留在初始位置,形成质量的拖尾分布;内爆后期驱动电流向外围的拖尾质量迁移,引发二次乃至三次内爆,后续内爆对K层辐射也有相当贡献.拖尾质量的出现与单丝等离子体上形成的轴向调制结构及不均匀性的发展有关.     

Porous Mn2O3: A Low‐Cost Electrocatalyst for Oxygen Reduction Reaction in Alkaline Media with Comparable Activity to Pt/C

Preparing nonprecious metal catalysts with high activity in the oxygen reduction reaction (ORR) can promote the development of energy conversion devices. Support‐free porous Mn₂O₃ was synthesized by a facile aerosol‐spray‐assisted approach (ASAA) and subsequent thermal treatment, and exhibited ORR activity that is comparable to commercial Pt/C The catalyst also exhibits notably higher activity than other Mn‐based oxides, such as Mn₃O₄ and MnO₂. The rotating ring disk electrode (RRDE) study indicates a typical 4‐electron ORR pathway on Mn₂O₃. Furthermore, the porous Mn₂O₃ demonstrates considerable stability and a good methanol tolerance in alkaline media. In light of the low cost and high earth abundance of Mn, the highly active Mn₂O₃ is a promising candidate to be used as a cathode material in metal–air batteries and alkaline fuel cells.     

用荧光光谱法研究OLED用的新型蓝色发光染料和三-（8-羟基喹啉）铝(AlQ_3)的光诱导电子转移和激基复合物的生成

在合成了三种新型发射蓝光化合物的基础上，对它们在溶液中的光物理行为作 了详细研究。发现它们的荧光能强烈地被三-（8-羟基喹啉）铝所猝灭，并在荧光 光谱的长谱部分出现因发生光诱导电子转移而生成激基复合物的发光。几个方面的 工作-如猝灭常数的测定，电子转移过程自由能的计算，都表明化合物荧光猝灭过 程的电子转移性质。此外，还讨论了因出现光诱导电子转移和激基复合物给OLED器 件带来的影响，特别对三种作为器件发射蓝光化合物的优劣进行了讨论，表明化合 物DPF有着最佳的发光特征。     

Sea anemone-like zinc-cobalt oxysulfides grown on Ni foam as a battery-type electrode with admirable performance

Sea anemone-like zinc-cobalt (Zn-Co) oxysulfides grown on nickel foam were synthesized by a hydrothermal treatment for the first time as a battery-type electrode for hybrid supercapacitors. Such a binder-free sea anemone-like Zn-Co oxysulfide electrode displays improved electrochemical properties, which can be attributed to the unique sea anemone-like morphology and the partly replacement of oxygen with sulfur since sulfur possesses a lower electronegativity. As a result, the Zn-Co oxysulfide electrode exhibits a specific capacity of 645.5 C g^?1 (1 A g^?1) which is much higher than 386.0 C g^?1 of Zn-Co oxide electrode at the same conditions. In addition, the Zn-Co oxysulfide electrode also demonstrates good cycling stability (76.1% capacity retention after 1000 cycles). According to these, the Zn-Co oxysulfide electrode is testified to be a promising faradaic electrode for energy storage.     

Simultaneous reduction-etching route to Pt/ZnSnO3 hollow polyhedral architectures for methanol electrooxidation in alkaline media with superior performance

In this communication, a simultaneous reduction-etching route is exploited to fabricate Pt/ZnSnO(3) hollow polyhedra. The hollow ZnSnO(3) polyhedron is found to act as a novel and efficient support of Pt-based catalyst for methanol electrooxidation in alkaline media.     

Gold-platinum yolk-shell structure: a facile galvanic displacement synthesis and highly active electrocatalytic properties for methanol oxidation with super CO-tolerance

In this communication, we prepare a Au-Pt yolk-shell structure through a galvanic displacement strategy and explore its electrocatalytic properties for methanol oxidation. It exhibits high electrocatalytic activity with notable CO-tolerance.