Enhancing the phototherapy efficacy of organic photosensitizers through molecular design is a fascinating but challenging task. Herein, we propose a simple design strategy to first realize the generation of superoxide anion radical (O 2•− ) by A−D−A fused-ring photosensitizers. Through replacing one cyano group of traditional end group with an ester group, we designed a novel nonplanar end group (A unit) to synthesize a novel A−D−A photosensitizer F8CA. In a comparison with its counterpart F8CN with the traditional end group, F8CA displays more loose packing and larger spin−orbit coupling constants. The F8CA nanoparticles showed higher photodynamic activities with the generation capability of singlet oxygen ( 1 O 2 ), hydroxyl radical ( • OH), and O 2•− , while F8CN nanoparticles could only generate 1 O 2 and • OH. In addition, F8CA nanoparticles still remain high photothermal conversion efficiency (61%). As a result, F8CA nanoparticles perform well in hypoxia-tolerant tumor phototherapy. This study brings an effective design thought for A−D−A photosensitizers.

Tumor phototherapies mainly including photothermal therapy (PTT) and photodynamic therapy (PDT) have drawn more and more attention due to their various merits of minimal drug resistance, low invasiveness and good...

By studying the substrate material, structure, chip distribution, and array form of the multi-chip light-emitting diode (LED) package, the heat-dissipation capacity of the LED package is improved. Finite element analysis and steady-state thermal analysis are used to simulate and analyze LED packages with different materials and structures. Using the theory of LED illuminance and uniformity, the illuminance of some structures is computed. The results show that the change of substrate material and structure can greatly impact heat dissipation, while changing array forms has little effect on heat dissipation. By improving the spatial distribution of the chip, the temperature superposition problem of the substrate is solved, and the illuminance and uniformity are improved while dissipating heat. The LED filaments of the combined, equidistant, chip-distribution mode have improved heat dissipation. The S-type equal difference has the highest illumination and high illumination uniformity.

With the increase of power level and integration in electric vehicle controllers, the heat flux of the key silicon-based IGBT (Insulated Gate Bipolar Transistor) device has reached its physical limit. At present, third-generation semiconductor devices including SiC MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistor) are gradually replacing the dominant IGBT module. The hybrid IGBT module consists of both and can improve the performance and reduce the cost of controllers. Limits due to the installation space, location, and other conditions in the car make it difficult to meet the requirements of controllers with an air-cooled heatsink due to their large size and limited heat dissipation capacity. A smaller and more powerful water-cooled heatsink case is required to ensure the heat dissipation of the IGBT in the controller. Based on previous experience in finite element numerical simulation, hydrodynamics calculation, and heat transfer calculation, ANSYS Workbench finite element software was used to analyze the thermal resistance of each structure inside the module and the heatsink structure. The fluid characteristics and heat transfer performance of three different flow channel structures were analyzed, and the design of the cooling flow fin was improved to provide a reference for the heat dissipation of the hybrid IGBT module.

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摘 要: 本研究采用基于密度泛函理论的第一性原理计算了类石墨烯单层结构 ZnO (g-ZnO) 和 GaN (g-GaN)的力 学、电学和压电性质，重点研究了施加应变后原子坐标弛豫与否的 Clamped-ion 和 Relaxed-ion 两种模式的弹性刚 度系数和压电张量。结果表明单层 g-ZnO 和 g-GaN 均具有半导体属性和较好的弹性。单层 g-ZnO 和 g-GaN 的压 电系数分别约为 9.4 和 2.2 pm• V-1 ，预测这类单层材料在极薄的器件中可能具有压电效应，且 g-ZnO 的压电性能更 好。因此，类石墨烯单层 ZnO 有望用于压力传感器、制动器、换能器及能量收集器等纳米尺度器件。

For rocket silo launching, the heat transfer and ablation problem of glass wool, the main material of silencer layer. The glass wool with severely ablated area was selected as research object, and a unidirectional fluid-structure coupled heat transfer ablation model was established. Through the secondary development of abaqus subroutine, the influence of silo diameter and initial impact height of jets flow on the ablation of glass wool was studied using factor decoupling control method. The simulation results show that reducing diameter of silo can aggravate the ablation damage of glass wool in the process of rocketing out of silo. During the tempering phase of jets flow field, the smaller silo diameter is, the higher the peak value of average ablation rate is, and the sooner the peak value appears; Increasing initial impact height of jets flow can mitigate the ablation damage of glass wool in the process of rocketing out of silo. During the tempering phase of jets flow field, the greater initial impact height of jets flow is, the smaller the peak value of average ablation rate is, and the later the peak appears. Changing silo diameter and initial impact height of jets flow have less effect on the ablation damage of glass wool during the drainage stage and subsequent stages of jets flow field.

BODIPY photosensitizers have been integrated with a hypoxia‐activated prodrug to achieve synergistic photodynamic therapy (PDT) and chemotherapy. A novel BODIPY derivative BDP‐CN was designed and synthesized. It had two cyano groups to make it complex well with a water‐soluble pillar[5]arene. Their association constant was calculated to be (6.8±0.9)×106 M−1. After self‐assembly in water, regular spherical nanocarriers can be formed; these were used to encapsulate the hypoxia‐activated prodrug tirapazamine (TPZ). BDP‐CN displayed excellent photodynamic activity to complete PDT. In this process, O2 can be continuously consumed to activate TPZ to allow it to be converted to a benzotriazinyl (BTZ) radical with high cytotoxicity to complete chemotherapy. As a result, the formed nanoparticles showed excellent synergistic photodynamic therapy and chemotherapy efficacy. The synergistic therapy mechanism is discussed in detail.