Chemically bonded assembly and photophysical properties of luminescent hybrid polymeric materials embedded into silicon–oxygen network and carbon unit

Through the reaction between the hydroxyl groups of 2-hydroxyl-3-methylbenzoic acid (HMBA), the glycol (G), the diglycol (DG) or the polyethylene glycol (PEG) and the isocyanate groups of 3-(triethoxysilyl)-propyl isocyanate (TEPIC), the hybrid precursors HMBA-Si, G-Si, DG-Si and PEG-Si were obtained. And then the precursors HMBA-Si and G-Si (DG-Si, PEG-Si) have coordinated to the rare earth ions with the carbonyl group of G-Si (DG-Si, PEG-Si) and the carboxyl group of HMBA-Si to form the hybrid materials HMBA-G-RE-Si (HMBA-DG-RE-Si, HMBA-PEG-RE-Si) through hydrolysis and copolycondensation with the tetraethoxysilane (TEOS) via sol–gel process. Subsequently, the NMR, FT-IR and ultraviolet absorption spectra have indicated that the effective precursors have been obtained successfully and the obtained materials possess the characteristic fluorescent properties, thermal stabilities and regular trunk with hole-like microstructures.     

Synthesis of phenothiazine-functionalized porphyrins with high fluorescent quantum yields

Two porphyrins with oligo-phenothiazine arms have been synthesized by a combination of Heck and Adler reaction, and their photophysical properties have been investigated by absorption and steady-state fluorescence spectroscopy. It is found that the excitation energy transfer occurs from the phenothiazine units to the porphyrin core, and that the porphyrins can emit intense red light with high fluorescent quantum yields.     

Enhanced targeted energy transfer for adaptive vibration suppression of pipes conveying fluid

Nonlinear Dynamics - In this paper, a nonlinear energy sink and a negative stiffness element are integrated for achieving enhanced, passive, and adaptive vibration suppression for a pipe conveying...     

套代数上高阶导子的刻画

设N是Banach空间X上的套,AlgN是相应的套代数。本文证明了,若套N中存在一个非平凡元在X中可补,那么AlgN上的每个可加Jordan高阶导子和每个可加三重Jordan高阶导子都是高阶导子。     

化学化工虚拟仿真实验教学平台的建设与应用

Virtual simulation teaching is a new type of teaching mode in recent years, which is a fusion of multiple disciplines, multiple regions and multi-level laboratory teaching methods. Taking virtual simulation experiment platform construction of chemical engineering in Tianjin University as an example, this paper introduces the chemical safety knowledge, the integration of theoretical knowledge, the experimental content, the specific content of virtual simulation resources, and the characteristic of virtual simulation experiment platform. This platform provides a new model of efficient combination of virtual simulation resources and traditional teaching resources, which promotes the development of chemical laboratory teaching.     

A blue luminescent binuclear cadmium-orotate coordination polymer: synthesis,crystal structure,and thermogravimetric analysis

Assembly of orotic acid (H₃Or, 1,2,3,6-tetrahydro-2,6-dioxo-4-pyrimidinecarboxylic) and Cd(NO₃)·6H₂O yielded a coordination polymer, [(Cd(Hor)·2.5H₂O)₂]_n (1), which has been characterized by X-ray single-crystal diffraction, TGA, and ?uorescence spectra. Single-crystal X-ray structural analyses reveal that 1 is a hydrogen-bonded binuclear Cd-orotate coordination polymer in which both Cd²⁺ ions have different coordination environments with identical distorted octahedral geometry. Crystal data for 1: monoclinic, space group P2₁/n, a = 7.0209(10) Å, b = 13.974(2) Å, c = 17.541(3) Å, β = 98.842(2)°, V = 1700.5(4) Å, Z = 4, R1 = 0.0269, wR2 = 0.0612, θ_max = 25.960. The emission spectrum of the Cd-complex recorded with 265 nm excitation wavelength reveals the complex has strong blue luminescence with the peak maximum 420 nm (2.95 eV) as a result of the n–π* and π–π* transitions on the H₃Or ligand.     

Flexible Li-CO2 Batteries with Liquid-Free Electrolyte

Developing flexible Li-CO₂ batteries is a promising approach to reuse CO₂ and simultaneously supply energy to wearable electronics. However, all reported Li-CO₂ batteries use liquid electrolyte and lack robust electrolyte/electrodes structure, not providing the safety and flexibility required. Herein we demonstrate flexible liquid-free Li-CO₂ batteries based on poly(methacrylate)/poly(ethylene glycol)-LiClO₄-3 wt %SiO₂ composite polymer electrolyte (CPE) and multiwall carbon nanotubes (CNTs) cathodes. The CPE (7.14×10⁻² mS cm⁻¹) incorporates with porous CNTs cathodes, displaying stable structure and small interface resistance. The batteries run for 100 cycles with controlled capacity of 1000 mAh g⁻¹. Moreover, pouch-type flexible batteries exhibit large reversible capacity of 993.3 mAh, high energy density of 521 Wh kg⁻¹, and long operation time of 220 h at different degrees of bending (0–360°) at 55 °C.