A Novel Ternary Composite of Polyurethane/Polyaniline/Nanosilica with Antistatic Property and Excellent Mechanical Strength: Preparation and Mechanism

Chinese Journal of Polymer Science - Antistatic and strength properties are of vital importance for polyurethane rubber used in moving parts of many industrial instruments. Herein, polyurethane was...     

Type I Photosensitizer Targeting G-Quadruplex RNA Elicits Augmented Immunity for Cancer Ablation

Type I photodynamic therapy (PDT) represents a promising treatment modality for tumors with intrinsic hypoxia. However, type I photosensitizers (PSs), especially ones with near infrared (NIR) absorption, are limited and their efficacy needs improvement via new targeting tactics. We develop a NIR type I PS by engineering acridinium derived donor-π-acceptor systems. The PS exhibits an exclusive type I PDT mechanism due to effective intersystem crossing and disfavored energy transfer to O₂, and shows selective binding to G-quadruplexes (G4s) via hydrogen bonds identified by a molecular docking study. Moreover, it enables fluorogenic detection of G4s and efficient O₂⋅⁻ production in hypoxic conditions, leading to immunogenic cell death and substantial variations of gene expression in RNA sequencing. Our strategy demonstrates augmented antitumor immunity for effective ablation of immunogenic cold tumor, highlighting its potential of RNA-targeted type I PDT in precision cancer therapy.     

高能电子辐照绝缘厚样品的表面电位动态特性

采用数值计算和实验测量相结合的方法, 阐明了高能电子束照射下绝缘厚样品的表面电位和电子产额动态特性. 结果表明: 由于电子在样品内部的散射和输运, 沿着深度方向, 空间电位先缓慢下降到最小值, 然后逐渐升高并趋近于零; 随着电子束照射, 样品的表面电位逐渐下降, 可至负千伏量级, 电子总产额逐渐增大至一个接近于1的稳定值; 电子束停止照射后, 长时间放置下, 表面电位将逐渐升高, 但带电并不会消除; 表面电位随电子束能量的升高近似线性下降, 随入射角的增大而升高, 而随样品厚度的增大仅略有下降.     

低能质子束在氢等离子体中的能损研究

实验测量了100 keV的质子束穿过部分电离氢等离子体靶后的能量损失. 等离子体靶由气体放电方式产生, 其自由电子密度在10¹⁶ cm^-3量级, 电子温度约1–2 eV, 维持时间在微秒量级. 研究结果表明: 质子束在等离子体靶中的能量损失与自由电子密度密切相关且明显大于在同密度条件下中性气体靶中的能量损失; 在自由电子密度达到峰值处, 通过实验结果计算得到此时的自由电子库仑对数约为10.8, 与理论计算结果符合较好, 该值比Bethe公式给出的中性气体靶中束缚电子库仑对数高4.3倍,相应的能损增强因子为2.9.     

Theoretical studies on N-loss predissociation mechanisms of N2O+ (A?2Σ+) in Cs symmetry

The N-loss predissociation mechanisms of the A ²Σ⁺ (2 ² A′) state of N₂O⁺ to the first and second dissociation limits were studied in the C _s symmetry. The potential energy curves (PECs) and minimum energy crossing points (MECPs) for the C _s states of N₂O⁺ were calculated at the CAS levels. On the basis of our CAS calculation results (CASPT2 energetic results and CASSCF spin orbit couplings), we suggest two processes for N-loss predissociation mechanisms of A ²Σ⁺ (2 ² A′) to the first and second limits. The first two steps in the two processes are the same: A ²Σ⁺ passes through the 2 ² A′/1 ⁴ A″ MECP and then reaches the 1 ⁴ A″ (1 ⁴Σ⁻) PEC. The 2 ² A′/1 ⁴ A″ MECP has a bent geometry and is slightly higher in energy than the transition state along the 1 ⁴ A″ PEC. Our mechanisms are different from the previously suggested mechanisms (via 1 ⁴Π).     

CdS@g-C3N4复合核壳纳米微粒的制备与光催化性能

采用水热法,在乙二胺和EDTA-2Na作用下,成功制备了CdS@g-C3N4复合核壳纳米微粒,并探讨了其生长机理。结果显示:CdS@g-C3N4复合核壳纳米微粒的比表面积是纯CdS纳米颗粒的14.0倍,具有良好的光催化活性和光稳定性。当反应条件为180℃、4 h、CdS/g-C3N4质量比1.9∶1时,CdS@g-C3N4的可见光催化性能最好,300 W氙灯光照2 h,RhB的降解率达95.2%,明显高于纯CdS。重复使用3次后,CdS@g-C3N4形貌、结构及光催化性能无明显变化。     

Unified flexible total synthesis of chlorofusin and artificial Click mimics as antagonists against p53–HDM2 interactions

A practical HPLC-free total synthesis of chlorofusin has been successfully accomplished in this work. The new synthesis showed great flexibility and convenience in generating artificial natural product-like mimics through Click chemistry, and enabled us to further investigate the biological importance of the chromophore and the spiro-aminal functionality of the natural product. The entire skeleton is believed to be essential for satisfactory biological activities of both natural chlorofusin and unnatural mimics. Two artificial Click hybrids were found to exhibit improved inhibitory activity against p53–HDM2 bindings over the natural product.     

隔膜式电解槽生物膜阴极降解苯酚的过程及其条件的优化

以炼油废水中的主要污染物苯酚为目标污染物, 采用不同生物膜电极反应器对苯酚进行降解, 从而寻找出降解苯酚的最佳反应途径. 研究结果表明, 运用隔膜式电解槽生物膜阴极区域对苯酚废水进行处理, 其苯酚的去除效果虽然没有在生物膜阴极与阳极相混合的混合式反应器中处理效果好, 但在18 h内苯酚浓度降解到0, 并且其化学需氧量(COD)去除率最高, 在16 h内COD去除率达到80%. 对于隔膜式电解槽生物膜阴极区域的降解条件优化后发现, 电流设定为5 mA, 初始苯酚质量浓度低于200 mg/L, 温度为35 ℃时, 苯酚降解效果最佳.