Improving the rate performance and stability of LiNi<Subscript>0.6</Subscript>Co<Subscript>0.2</Subscript>Mn<Subscript>0.2</Subscript>O<Subscript>2</Subscript> in high voltage lithium-ion battery by using fluoroethylene carbonate as electrolyte additive

Fluoroethylene carbonate (FEC) is investigated as the electrolyte additive to improve the electrochemical performance of high voltage LiNi_0.6Co_0.2Mn_0.2O₂ cathode material. Compared to LiNi_0.6Co_0.2Mn_0.2O₂/Li cells in blank electrolyte, the capacity retention of the cells with 5 wt% FEC in electrolytes after 80 times charge-discharge cycle between 3.0 and 4.5 V significantly improve from 82.0 to 89.7%. Besides, the capacity of LiNi_0.6Co_0.2Mn_0.2O₂/Li only obtains 12.6 mAh g^?1 at 5 C in base electrolyte, while the 5 wt% FEC in electrolyte can reach a high capacity of 71.3 mAh g^?1 at the same rate. The oxidative stability of the electrolyte with 5 wt% FEC is evaluated by linear sweep voltammetry and potentiostatic data. The LSV results show that the oxidation potential of the electrolytes with FEC is higher than 4.5 V vs. Li/Li⁺, while the oxidation peaks begin to appear near 4.3 V in the electrolyte without FEC. In addition, the effect of FEC on surface of LiNi_0.6Co_0.2Mn_0.2O₂ is elucidated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The analysis result indicates that FEC facilitates the formation of a more stable surface film on the LiNi_0.6Co_0.2Mn_0.2O₂ cathode. The electrochemical impedance spectroscopy (EIS) result evidences that the stable surface film could improve cathode electrolyte interfacial resistance. These results demonstrate that the FEC can apply as an additive for 4.5 V high voltage electrolyte system in LiNi_0.6Co_0.2Mn_0.2O₂/Li cells.     

交叉流聚丙烯中空纤维膜式氧合器的传质研究Ⅰ结构因子α、β的测定和氧合器传质效果评价

在膜式氧合器水气传递实验装置上分别对二种不同的交叉流微孔聚丙烯中空纤维膜式氧合器进行了水气传递实验，测得了氧合器的结构因子α、β，并用Ｍｏｃｋｒｏｓ和Ｌｅｏｎａｒｄ对Ｏ２传递建立的半经验数学模型拟合了血气传递实验中氧气在血中的传递速率。结果表明，理论计算与实验数据十分吻合，偏差小于１０％。讨论了α、β与膜式氧合器的传递效果的关系。     

Isomorphisms of fiber spaces over Teichmüller spaces

We will be mainly concerned with some important fiber spaces over Teichmüller spaces, including the Bers fiber space and Teichmüller curve, establishing an isomorphism theorem between “punctured” Teichmüller curves and determining the biholomorphic isomorphisms of these fiber spaces.     

The gas–liquid tunable self-assembly properties of rod–coil diblock copolymer: donor–acceptor alternating structure served as rod segment

The rod–coil diblock copolymers in which the donor–acceptor alternating structures served as the rod segment were synthesized. The supramolecular self-assembly property of the copolymers was investigated in the methanol atmosphere. By changing the assembly condition, well-defined vesicles and porous films were produced, respectively. Pores with different size dispersions were obtained by tuning the methanol atmosphere. Moreover, porous films were also decorated on diverse substrates with nonplanar structures. The investigation on self-assembly properties of this rod–coil copolymer is the complementarity to the self-assembly of rod–coil copolymers. This is a very useful self-assembly method that can be used to prepare the self-assembly nanostructures with donor–acceptor alternating copolymers.     

Ag cluster-aptamer hybrid: specifically marking the nucleus of live cells

Silver cluster-aptamer hybrids were mineralized via an artificially designed aptamer. The hybrids gave red emission when excited by light, and they successfully targeted the nucleus of live cells. This method is an effective approach to make cell target probes.     

Enhanced white-light emission from multiple fluorophores encapsulated in a single layer of diblock copolymer micelles

Enhanced white-light emission was achieved by loading green- and red-light-emitting donor-acceptor pairs in the separate micellar cores and blue-light-emitting polymers around their periphery. Fluorescence resonance energy transfer was enabled between a donor and an acceptor in cores, but was suppressed among these three light-emitting species by micellar coronas, which resulted in their enhanced simultaneous emissions.     

Controllable Assembly of Highly Oxidized Cobalt on Graphdiyne Surface for Efficient Conversion of Nitrogen into Nitric Acid

The manufacture of nitric acid (HNO₃) consumes large amounts of energy and causes serious environmental pollution. Electrochemical synthesis is regarded as a key way to eliminate carbon emissions from the chemicals industry. The selective electrosynthesis of HNO₃ from nitrogen was achieved by controllable assembly of cobalt metal on graphdiyne surface using a powerful tool of electrochemistry at ambient conditions. As an advanced material, graphdiyne (GDY) has a large conjugated structure on its surface and is rich in sp-C triple bond skeleton, which can achieve strong interaction with metal atoms, resulting in incomplete charge transfer between graphdiyne and cobalt atoms. The experimental and theoretical calculation results show that the highly oxidized cobalt on graphdiyne (HOCo/GDY) can selectively and efficiently activate and convert the nitrogen into the key intermediate *NO, which promotes the efficient overall conversion performance of nitrogen to nitric acid. Thus, the highest nitric acid yield (192.0 μg h⁻¹ mg⁻¹) and Faradaic efficiency (21.5 %) were achieved at low potentials.     

Engineering biomimetic epigenetic nanoinducer improves cancer immunotherapy

Immunotherapy such as immune checkpoint blockade (ICB)and adoptive cell transfer is a revolutionary advance in the field of cancer therapy by providing clinical...     

SOI全内反射型光波导电光开关模型研究

根据受抑全反射的光学隧道效应和Ｇｏｏｓ－Ｈａｎｃｈｅｎ位移分析ＳＯＩ全内反射型光波导开关中导模的传输和反射特性。在讨论等离子体色散效应，ｐ－ｎ结大注入效应的基础上，分析了全内反射光波导开关的电学性质。设计了该器件的结构以数和电学参数。     

聚合物载体-稀土金属配合物的研究聚（苯乙烯－丙烯酰胺）载体－氯化钕配合物对?

研究了聚（苯乙烯－丙烯酰胺）（ＰＳＡＣ）载体－氯化钕配合物催化丁二烯聚合的规律，考察了ＰＳＡＣ载体及ＰＳＡＣ·ＮｄＣｌ３配合物的组成与催化活性间的关系．ＰＳＡＣ载体的收率不影响配合物的活性，而配合物的活性却随ＰＳＡＣ载体中Ｃ（Ｏ）ＮＨ２功能团含量的高低而改变，含量低时活性高．ＰＳＡＣ载体与配合物的组成不影响所得聚丁二烯的微观结构