Afterglow Implant for Arterial Embolization and Intraoperative Imaging

Transcatheter arterial embolization (TAE) is wildly used in clinical treatments. However, the online monitoring of the thrombosis formation is limited due to the challenges of the direct visualization of embolic agents and the real-time monitoring of dynamic blood flow. Thus, we developed a photochemical afterglow implant with strong afterglow intensity and a long lifetime for embolization and imaging. The liquid pre-implant injected into the abdominal aorta of mice was rapidly transformed into a hydrogel in situ to embolize the blood vessel. The vascular embolism position can be observed by the enhanced afterglow of the fixed implant, and the long lifetime of afterglow can also be used to monitor the effect of embolization. This provides an excellent candidate in bio-imaging to avoid the autofluorescence interference from continuous light excitation. The study suggests the potential usefulness of the implant as an embolic agent in TAE and artery imaging during a surgical procedure.     

Dye Sensitization Offers a Brighter Afterglow Nanoparticle Future for in vivo Recharged Luminescent Imaging

While concerns about improving recharged afterglow intensity in vivo still motivate further exploration, afterglow nanoparticles (AGNP) offer unique optical merit for autofluorescence-free biological imaging. Apart from efforts enhancing the afterglow emission properties of AGNP, improving afterglow excitation response to visible or near infrared light is important but has lacked success. Dye sensitization has been used to improve the optical response of photovoltaic nanomaterials and to enhance upconversion luminescence efficiency. This concept has recently been expanded and applied to AGNPs. As a new multifunctional nanoprobe, such dye-sensitized AGNP takes advantage of both high spatial resolution fluorescence imaging and sensitive afterglow imaging. This Concept introduces the background, the concept, mechanism, and related imaging application, as well as reviewing existing challenges and proposing future developmental directions for the dye-sensitized AGNPs.     

Manipulation of Organic Afterglow by Thermodynamic and Kinetic Control

The fabrication of room-temperature organic phosphorescence and afterglow materials, as well as the transformation of their photophysical properties, has emerged as an important topic in the research field of luminescent materials. Here, we report the establishment of energy landscapes in dopant-matrix organic afterglow systems where the aggregation states of luminescent dopants can be controlled by doping concentrations in the matrices and the methods of preparing the materials. Through manipulation by thermodynamic and kinetic control, dopant-matrix afterglow materials with different aggregation states and diverse afterglow properties can be obtained. The conversion from metastable aggregation state to thermodynamic stable aggregation state of the dopant-matrix afterglow materials to leads to the emergence of intriguing afterglow transformation behavior triggered by thermal and solvent annealing. The thermodynamically unfavorable reversible afterglow transformation process can also be achieved by coupling the dopant-matrix afterglow system to mechanical forces.     

Sr0.6Ba0.2Ca0.2Al2O4 ∶Eu,Dy的制备与长余辉发光性能研究

采用高温固相法制备了Ca,Ba共掺的Sr_0.6Ba_0.2Ca_0.2Al₂O₄ ∶Eu²⁺_0.01, Dy³⁺_0.02和单掺Ba的Sr_0.6Ba_0.4Al₂O₄ ∶Eu²⁺_0.01, 关键词： 长余辉 铝酸锶 稀土掺杂 陷阱能级     

通过棒状金属羧酸/羟基次级结构单元形成的锌金属有机骨架的低温余晖性质

通过一个含3个羧基基团的多功能配体2-羟基-1，3，5-苯基三羧酸（HO-H₃BTC）与锌盐构筑了一个三维多孔锌骨架结构配合物，{[Zn₄（O-BTC）₂（H₂O）₅]·2DMF·0.5H₂O}_n（1）。通过单晶X射线衍射、粉末X射线衍射、元素分析、红外光谱、热重分析以及固体紫外吸收光谱对该配合物进行了表征。配合物1是通过棒状金属锌-羧酸/羟基次级结构单元构筑的一个三维骨架结构，其在室温下显示强烈的蓝色荧光。此外，在低温条件下（10 K）配合物1显示余晖性质。     

实验优化设计Sr_2MgSi_2O_7:Eu~(2+),Dy~(3+)的合成及长余辉特性

为了得到最长有效余辉时间的Sr_2MgSi_2O_7:Eu~(2+),Dy~(3+)荧光粉,应用二次通用旋转组合设计对实验进行全程优化,建立了稀土离子掺杂浓度Eu~(2+),Dy~(3+)和有效余辉时间的二元二次回归方程模型,应用遗传算法计算得到有效余辉时间的理论最大值.采用高温固相法合成了最优掺杂浓度Sr_2MgSi_2O_7:0.5mol%Eu~(2+),1.0mol%Dy~(3+)的荧光粉,在370nm激发下观察到了465nm的特征发射,这归因于Eu~(2+)的4f65d1—4f7跃迁.测量了最优荧光粉的热释发光特性,计算得到了陷阱深度为0.688eV,讨论了长余辉发光的特性.     

Room‐Temperature Phosphorescence in Metal‐Free Organic Materials

Purely organic materials with room‐temperature phosphorescence (RTP) have attracted a growing interest for their potential applications in biological imaging, digital encryption, optoelectronic devices, and so on. To date, many strategies have succeeded in designing efficient organic RTP materials by overcoming the spin‐forbidden transition between singlet and triplet states. However, the underlying mechanisms of RTP still remain ambiguous. Such spin prohibition in phosphorescence are clarified, herein, from the perspective of perturbation theory, helping to understand the intrinsic relationship among various phosphorescence parameters, like phosphorescence efficiency, lifetime, intersystem crossing rate, as well as radiative and nonradiative rates. Taking into consideration the recent progress in organic RTP materials, these factors are further illustrated by a selection of the most relevant molecules. In addition, some novel RTP phenomena are also reviewed, thus providing an excellent guideline to constructing efficient RTP materials.     

Ar (3P0,2 )与SO2反应产生SO (A″ 3Σ+)的光谱

On the flowing afterglow apparatus, in the energy transfer reaction between Ar (3P0,2) and SO2, two series of spectra were observed at two different downstream optical windows from the discharge region. According to the data obtained in this group’s report on the discharge of the mixture of Ar with SO2 and spectral simulation, the two spectrum progressions in the range of 320 and 600 nm were assigned to SO (A″3Σ+→X 3Σ-) and SO (c 1Σ-→X 3Σ-), respectively. The spectroscopic constants for the new electronic state were obtained by spectral simulation based on the method of the least square and shown as follows: T00 =(30460±18.0) cm-1, ωe′=(685±0.8) cm-1 and ωe′χe′=(7.7±8.0) cm-1.     

Pb在锗酸镉基质中的长余辉发光特性

通过高温固相反应在空气中制得单相Cd₂Ge₇O₁₆:Pb²⁺长余辉发光材料.分析了Cd₂Ge₇O₁₆和Cd₂Ge₇O₁₆:Pb²⁺的激发光谱和发射光谱,指出Pb²⁺的发光是该离子的³P₁-¹S₀跃迁产生的;分析了Cd₂Ge₇O₁₆:Pb²⁺的发光存在基质对Pb²⁺的能量传递;并把长余辉性质归结为基质中Cd离子的挥发产生的空穴陷阱.提出了长余辉发光机理模型.     

长余辉发光材料研究进展

长余辉发光材料是一类重要的光-光转换和节能材料。这类材料在工农业生产、军事、消防和人们生活的许多方面得到广泛应用。本文主要结合本课题组近年在长余辉发光材料领域的研究工作,综述长余辉发光材料的研究进展,并对今后的发展方向进行展望。