Self-assembling poly(dioxaborole)s as blue-emissive materials

Conjugated, borole-linked polymers have been self-assembled based on boronate ester formation between a fluorene-2,7-diboronic acid and 1,2,4,5-tetrahydroxybenzene. Readily soluble polymers with molecular weights approaching 60 000 have been generated with materials exhibiting extended conjugation over approximately 3-5 borole linkages. Emission from these polymers reaches into the visible (blue) range, representing a novel class of blue-emitting materials.     

Existence results for nonlinear nonlocal problems in Banach spaces

This work is concerned with nonlinear differential equations with nonlocal conditions in Banach spaces. Using the theory of nonlinear semigroups and approximation techniques, a new existence result is obtained, for integral solutions. An example is also given to illustrate the abstract theory.     

In situ anchor of Na2Ti3O7 in nitrogen-rich carbon hollow red blood cell-like structure as a 0D-3D hierarchical electrode material for efficient electrochemical desalination

Reasonable design of the structure and complementary compounding of electrode materials is helpful to enhance capacitive deionization (CDI) performance. Herein, a novel 0D–3D hierarchical electrode material containing Na₂Ti₃O₇ nanoparticles anchored at hollow red blood cell (HRBC)-like nitrogen-rich carbon (HRBC-NTO/N-C-60) was prepared via selective protection, pyrolysis, and alkalization. Specifically, a HRBC-like NH₂-MIL-125-based material (HRBC-MOF-60) was first constructed by a selective protection approach of tannic acid (TN), which addresses the shortcomings of using sacrificial templates or corrosive agents. Afterwards, HRBC-NTO/N-C-60 was obtained in situ by annealing and alkalization of HRBC-MOF-60. The nitrogen-rich carbon with a HRBC-like structure has the ability to rapidly transport electrons, and its porous structure enables remarkable charge transfer. Benefiting from the grafted 3D N-doped porous carbon with a HRBC-like structure, well-dispersed 0D Na₂Ti₃O₇ nanoparticles, and satisfactory bonding effects, HRBC-NTO/N-C-60 exhibited high specific capacitance and fast ionic and electronic diffusion kinetics. Moreover, HRBC-NTO/N-C-60 was well-suited for desalination by functioning as a cathode material for capacitive deionization (CDI), and delivering a high desalination capacity of 66.8 mg g⁻¹ in 200 mg L⁻¹ NaCl solution at 1.4 V. This work introduces an excellent high-performance candidate for electrochemical deionization as well as affording afflatus for accurately inventing OD-3D hierarchical materials with hollow structures.

Hollow red cell-like Na₂Ti₃O₇/nitrogen-doped carbon are synthesized by a template-self strategy.     

Design,Synthesis and Biological Evaluation of N-phenylindole Derivatives as Pks13 Inhibitors againstMycobacterium tuberculosis

Polyketide synthase 13 (Pks13), an essential enzyme for the survival of Mycobacterium tuberculosis (Mtb), is an attractive target for new anti-TB agents. In our previous work, we have identified 2-phenylindole derivatives against Mtb. The crystallography studies demonstrated that the two-position phenol was solvent-exposed in the Pks13-TE crystal structure and a crucial hydrogen bond was lost while introducing bulkier hydrophobic groups at indole N moieties. Thirty-six N-phenylindole derivatives were synthesized and evaluated for antitubercular activity using a structure-guided approach. The structure–activity relationship (SAR) studies resulted in the discovery of the potent Compounds 45 and 58 against Mtb H37Rv, with an MIC value of 0.0625 μg/mL and 0.125 μg/mL, respectively. The thermal stability analysis showed that they bind with high affinity to the Pks13-TE domain. Preliminary ADME evaluation showed that Compound 58 displayed modest human microsomal stability. This report further validates that targeting Pks13 is a valid strategy for the inhibition of Mtb and provides a novel scaffold for developing leading anti-TB compounds.     

Bessel驻波对椭球形液滴的声辐射转矩

在实际的声操控中,由于声辐射力、表面张力和重力的共同作用,液滴往往呈现出椭球的形状,在螺旋声场中会受到力矩的作用而发生转动。从声波的散射理论出发,根据部分波展开法求解得到了椭球形液滴在Bessel驻波场中的声散射系数,并给出了其受到的声辐射转矩的解析式。在此基础上,对椭球形不可压缩液滴和椭球形可压缩液滴分别进行数值计算。仿真结果表明,不可压缩液滴的声辐射转矩与声束半锥角的关系更密切,而可压缩液滴则更依赖于特定的频率;提升Bessel驻波场的阶数有利于增强声辐射转矩的峰值,但在中低频处较难对可压缩液滴产生明显的力矩。该研究结果预期对利用螺旋声场进行液滴的操控具有理论指导作用。      

用微量热法研究左金丸及类方药的药性差异

采用微量热法测定了大肠杆菌在左金丸、甘露散、茱萸丸和反左金丸水煮液作用下的生长热谱曲线,获得相应的生物热动力学参数,经主成份分析并结合本草文献报道,综合分析左金丸及类方的药性差异,以从生物物理和生物化学的角度,探讨中医经典类方药性差异的客观真实性.实验发现,左金丸及类方的水煮液对大肠杆菌的生长代谢表现出不同的活性作用.寒凉药方左金丸和甘露散不同程度的抑制细菌的生长代谢.温热药方反左金丸和茱萸丸对细菌的生长代谢有不同程度的促进作用.类方之间存在较稳定的药性差异.类方药性主要受生物热动力学参数:第二指数生长期的生长速率常数k2和最大发热功率Pm2的影响.     

超声平面波经颅成像相位校正方法

超声平面波经颅成像时,由于颅骨对超声传播的影响引起图像质量下降,需要对颅骨造成的超声相位畸变进行校正.为此,该文研究了两种相位补偿方法:基于近似射线声学的理论方法和基于时间反转的数值计算方法,并利用数值仿真对比了两种方法的补偿和成像效果.结果表明:无论使用近似射线法还是时间反转法,都能够有效地校正因颅骨造成的相位畸变;...     

A new black to highly transmissive switching bilayer polymer composite films with electroactive pEA as a color buffer layer for improving electrochromic stability

Two reported D-A-D monomers based on 3,4-ethylenedioxythiophene (EDOT) were selected for electrochemical copolymerization to obtain copolymer film, named pRG. Then, a soluble polymer poly[3,4-ethylenedioxythiophene-alt-3,4-bis([2-ethylhexyl]oxy)thiophene] (pEA) based on the EDOT derivative was screened out, which is complementary to the absorption trough of the pRG film in visible region and matched with its working potential. The bilayer composite film pRG/pEA was obtained by spinning pEA basement membrane on fluorine doped tin oxide (FTO) coated glass surface, and then in situ electrochemical polymerization of pRG film. Compared to the pRG monolayer film, the bilayer composite film shows a more saturated black color in the neutral state and significant improvement on cyclic stability (only decreased by 1.7% after 250 cycles, while pRG film decreased by 17.1%). The introduction of pEA buffer layer not only achieves the full spectral absorption of the composite film in the visible region, but also significantly improves the cyclic stability of the bilayer composite film. The assembled EC prototype device based on the pRG/pEA composite film exhibits a “black to high transmission” reversible switch. Finally, this method combining electrochemical copolymerization, spin-coating, lamination and other methods provides a new research idea for designing and preparing black to transmissive electrochromic materials.