Photoluminescent coordination polymer bulk glasses and laser-induced crystallization

We synthesized luminescent coordination polymer glasses composed of d¹⁰ metal cyanides and triphenylphosphine through melt-quenching and mechanical milling protocols. Synchrotron X-ray total scattering measurements and solid-state NMR revealed their one-dimensional chain structures and high structural dynamics. Thermodynamic and photoluminescence properties were tunable by the combination of heterometallic ions (Ag⁺, Au⁺, and Cu⁺) in the structures. The glasses are moldable and thermally stable, and over centimeter-sized glass monoliths were fabricated by the hot-press technique. They showed high transparency over 80% from the visible to near-infrared region and strong green emission at room temperature. Furthermore, the glass-to-crystal transformation was demonstrated by laser irradiation through the photothermal effect of the glasses.

Over centimeter-sized luminescent coordination polymer glasses were fabricated. They showed high transparency (over 80%) and strong green emission at room temperature. The glass-to-crystal transformation by laser irradiation was demonstrated.     

An evaluation of force terms in the lattice Boltzmann models in simulating shallow water flows over complex topography

Proper approximation of the force terms, especially the bed slope term, is of crucial importance to simulating shallow water flows in lattice Boltzmann (LB) models. However, there is little discussion on the schemes of adding force terms to LB models for shallow water equations (SWEs). In this study, we evaluate the performance of forcing schemes coupled with different LB models (LABSWE and MLBSWE) in simulating shallow water flows over complex topography and try to find out their intrinsic characteristics and applicability. Three cases are adopted for evaluation, including a stationary case, a one-dimensional tidal wave flow over an irregular bed, and a steady flow over a two-dimensional seamount. The simulating results are compared with analytical solutions or the results produced by the finite difference method. For LABSWE, all the forcing schemes, except for the weighting factor method, fail to produce accurate solutions for the test cases; this is probably due to the mismatch between the bed slope term in source terms and the quadratic depth term of the equilibrium distribution functions in these forcing schemes. For MLBSWE, all the forcing schemes are capable of simulating flows over the complex topography accurately; furthermore, those schemes taking into account the collision effect τ to eliminate the momentum induced by forces provide more accurate solutions with quicker convergence as the lattice size decreases. In this view, MLBSWE can bring more flexibility in treating the force terms and thus can be a better tool to simulate shallow water flows over complex topography in practical application.     

金属锂电池的热失控与安全性研究进展

锂离子电池在便携式储能器件及电动汽车领域得到了广泛应用,然而频繁发生的电池起火爆炸事故,使热失控和热安全问题备受人们关注,目前已有多篇综述报道了缓解锂离子电池热失控的措施。相比于已经接近理论比能极限的锂离子电池,金属锂负极具有更高的比容量、更低的电势和高反应活性,但是不可控的锂枝晶生长,使得金属锂电池的热失控问题更为复杂和严重。针对金属锂电池的热失控问题,本文首先介绍了热失控的诱因及基本过程和阶段,其次从材料层面综述了提高电池热安全性的多种策略,包括使用阻燃性电解质、离子液体电解质、高浓电解质和局域高浓电解质等不易燃液态电解质体系,开发高热稳定性隔膜、热响应隔膜、阻燃性隔膜和具有枝晶检测预警与枝晶消除功能的新型智能隔膜,以及研究热响应聚合物电解质,最后对金属锂电池热失控在未来的进一步研究进行了展望。     

Development of Multinuclear Polymeric Nanoparticles as Robust Protein Nanocarriers

One limitation of current biodegradable polymeric nanoparticles is their inability to effectively encapsulate and sustainably release proteins while maintaining protein bioactivity. Here we report the engineering of PLGA–polycation nanoparticles with a core–shell structure that act as a robust vector for the encapsulation and delivery of proteins and peptides. The optimized nanoparticles can load high amounts of proteins (>20 % of nanoparticles by weight) in aqueous solution without organic solvents through electrostatic interactions by simple mixing, thereby forming nanospheres in seconds with diameters <200 nm. The relationship between nanosphere size, surface charge, PLGA–polycation composition, and protein loading is also investigated. The stable nanosphere complexes contain multiple PLGA–polycation nanoparticles, surrounded by large amounts of protein. This study highlights a novel strategy for the delivery of proteins and other relevant molecules.     

Design,synthesis and antimycobacterial activity of novel nitrobenzamide derivatives

We report herein the design and synthesis of a series of novel nitrobenzamide derivatives. Results reveal that many of them display considerable in vitro antitubercular activity. Four N-benzyl or N- (pyridine-2-yl)methyl 3,5-dinitrobenzamides A6, All, Cl and C4 have not only the same excellent MIC values of0.016 μg/mL against both drug-sensitive MTB strain H37 Rv and two drug-resistant clinical isolates as PBTZ169 and the lead 1, but also acceptable safety indices (SI 1500), opening a new direction for further development.     

一种新型CO2/原油助混剂CAA8-X的应用与助混机理

CO₂驱是一种具有广阔前景的提高油藏采收率的方法。其中,降低CO₂与原油的最低混相压力以实现混相驱是增强CO₂驱效果的重要手段。由此我们设计了由亲油基团十六烷基和亲CO₂基团全乙酰蔗糖酯基结合的新型“亲油-亲CO₂助混分子”十六酸全乙酰基蔗糖酯CAA8-X,研究发现,CAA8-X对超临界CO₂流体和不同油相的煤油、白油以及长庆原油有优异的助混效果,界面张力消失法和细管实验法测定结果表明,CAA8-X可以将超临界CO₂/长庆原油的最低混相压力降低20.5%。用分子动力学模拟计算了CO₂分子与全乙酰蔗糖酯基的亲和能力,研究了这类新型“亲油-亲CO₂助混分子”通过多酯头基降低与CO₂亲和势能而降低油/CO₂界面能的助混机理。     

Influence of substrate temperature on the texture of barium ferrite film by magnetron sputtering

Barium ferrite thin films have been prepared by radio frequency magnetron sputtering on a sapphire (0 0 1) substrate at substrate temperature of 500 °C and 650 °C, respectively. The films were further annealed in air at 1000 °C for 5 h. X-ray diffraction shows that the films at the lower substrate temperatures have a good epitaxial relation with respect to the substrate, while the samples under the higher substrate temperatures have (1 0 9) planes parallel to the substrate. The remanence ratio decreases from 0.82 to 0.47 when the substrate temperature is increased. We attribute the variation of the growth direction to the enhanced vertical mobility of the deposited atoms when the substrate temperature is increased.     

Computer-Aided Living Polymerization Conducted under Continuous-Flow Conditions

Continuous-flow techniques have promoted the development of synthetic chemistry due to advantages such as outstanding mass/heat transfer,on-demand scalability,improved safety,precise regulation on reaction parameters,etc.Recently,the combination of flow polymerization with computer scienee has gained considerable interests,leading to a variety of cutting-edge synthetic techniques.This review summarizes emerging achievements realized via the integration of computer science and living flow polymerizations,including 1)high-throughput living polymerizations in flow,2)programmable regulations of dispersity profile,se-que nee and topology for polymers,3)modular desig n with on line mon itori ng,as well as 4)self-optimized living polymerizati ons in flow.We expect that this summary will furnish informative kno wledge to scie ntists in related directions and in spire new ideas to further empower on-demand polymer engineering with modern techniques.