Secondary Metabolites from Hericium erinaceus and Their Anti-Inflammatory Activities

Hericium erinaceus, a culinary and medicinal mushroom, is widely consumed in Asian countries. Chemical investigation on the fruiting bodies of Hericium erinaceus led to the isolation of one new ergostane-type sterol fatty acid ester, erinarol K (1); and eleven known compounds: 5α,8α -epidioxyergosta-6,22-dien-3β-yl linoleate (2); ethyl linoleate (3); linoleic acid (4); hericene A (5); hericene D (6); hericene E (7); ergosta-4,6,8(14),22-tetraen-3-one (8); hericenone F (9); ergosterol (10); ergosterol peroxide (11); 3β,5α,6α,22E-ergosta-7,22-diene-3,5,6-triol 6-oleate (12). The chemical structures of the compounds were determined by 1D and 2D NMR (nuclear magnetic resonance) spectroscopy, mass spectra, etc. Anti-inflammatory effects of the isolated aromatic compounds (5–7, 9) were evaluated in terms of inhibition of pro-inflammatory mediator (TNF-α, IL-6 and NO) production in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophage cells. The results showed that compounds 5 and 9 exhibited moderate activity against TNF-α (IC₅₀: 78.50 μM and 62.46 μM), IL-6 (IC₅₀: 56.33 μM and 48.50 μM) and NO (IC₅₀: 87.31 μM and 76.16 μM) secretion. These results supply new information about the secondary metabolites of Hericium erinaceus and their anti-inflammatory effects.     

Tl系超导薄膜金属涂层的生长与特性研究

我们研究了Tl-2212超导薄膜在带有YSZ/CeO2缓冲层和带有CeO2/YSZ/CeO2缓冲层的Ni金属RABiTS基带上的生长情况.基带上的缓冲层是采用PLD方法制备的,Tl-2212薄膜的制备采用了磁控溅射和后热处理两步方法.XRD 实验结果表明,Tl-2212薄膜都具有很好的C轴垂直于膜面的织构,并具有双向外延生长特性.在CeO2/YSZ/CeO2/Ni基带上制作的Tl-2212薄膜的Tc达到102.8 K,Jc(77 K,0 T)达到2.6 MA/cm2;在YSZ/CeO2/Ni基带上薄膜Tc可达97.7 K,Jc(77 K,0 T)也可以达到0.45 MA/cm2.     

高等数学教学改革研究进展

通过分析国内外高等数学教学改革研究历史与现状,阐明21世纪高等数学课程地位、作用和价值,及与21世纪相适应的高等数学教学改革意义、方向与方法.并结合个人教学实践分析、总结了具有代表性的高等数学教学理念、教学内容与课程体系、实践教学、计算机技术应用等方面改革成果与经验.最后对高等数学教学改革的继续深入和目前存在问题提出一些观点.     

混合纤芯光子晶体光纤超平坦色散的研究

利用平面波展开法,系统地研究了一种具有混合纤芯结构的光子晶体光纤的色散特性. 数值计算结果表明,通过优化结构参量,这种新型结构的光子晶体光纤在通信窗口1.55 μm 附近可以获得带宽超过800 nm的超平坦色散区域（色散曲线的变化范围不超过 ±0.6 ps·km－1·nm－1）.     

Optimizing the quasi-equilibrium state of hot carriers in all-inorganic lead halide perovskite nanocrystals through Mn doping: fundamental dynamics and device perspectives

Hot carrier (HC) cooling accounts for the significant energy loss in lead halide perovskite (LHP) solar cells. Here, we study HC relaxation dynamics in Mn-doped LHP CsPbI₃ nanocrystals (NCs), combining transient absorption spectroscopy and density functional theory (DFT) calculations. We demonstrate that Mn²⁺ doping (1) enlarges the longitudinal optical (LO)–acoustic phonon bandgap, (2) enhances the electron–LO phonon coupling strength, and (3) adds HC relaxation pathways via Mn orbitals within the bands. The spectroscopic study shows that the HC cooling process is decelerated after doping under band-edge excitation due to the dominant phonon bandgap enlargement. When the excitation photon energy is larger than the optical bandgap and the Mn²⁺ transition gap, the doping accelerates the cooling rate owing to the dominant effect of enhanced carrier–phonon coupling and relaxation pathways. We demonstrate that such a phenomenon is optimal for the application of hot carrier solar cells. The enhanced electron–LO phonon coupling and accelerated cooling of high-temperature hot carriers efficiently establish a high-temperature thermal quasi-equilibrium where the excessive energy of the hot carriers is transferred to heat the cold carriers. On the other hand, the enlarged phononic band-gap prevents further cooling of such a quasi-equilibrium, which facilitates the energy conversion process. Our results manifest a straightforward methodology to optimize the HC dynamics for hot carrier solar cells by element doping.

Mn doping modulates the hot carrier dynamics in all-inorganic lead halide perovskite nanocrystals according to the excitation energy.     

低聚水溶性壳聚糖修饰阿魏酸及细胞毒活性研究

阿魏酸（Ferulic acid,FA）,化学学名为4-羟基3-甲氧基苯丙烯酸,是当归、川芎、木贼、升麻、樟白皮等中药材水溶性提取物中主要的单体活性成份,属天然酚酸类化合物,由于其优良的抗氧化性,故对一些肿瘤表现出抑制作用,但活性不是很好。另外,由于FA的稳定性差,在人体内不参与肝肠循环等缺陷也影响其药效的发挥。     

Plasma assisted synthesis of LiNi0.6Co0.2Mn0.2O2 cathode materials with good cyclic stability at subzero temperatures

Layered Ni-rich cathode materials,LiNi_0.6Co_0.2Mn_0.2O₂(NCM622),are synthesized via solid reaction assisted with a plasma milling pretreatment,which is resulted in lowering sintering temperatures for solid precursors.The plasma milling pretreated NCM622 cathode material sintered at 780℃(named as PM-780)demonstrates good cycling stability at both room and subzero temperatures.Specifically,the PM-780 cathode delivers an initial discharge capacity of 171.2 mAh g^-1 and a high capacity retention of 99.7%after 300 cycles with current rate of 90 mA g^-1 at 30℃,while stable capacities of 120.3 and 94.0 m Ah g^-1 can be remained at-10℃and-20℃in propylene carbonate contained electrolyte,respectively.In-situ XRD together with XPS and SEM reveal that the NCM622 cycled at-10℃presented better structural stability and more intact interface than that of cathodes cycled at 30℃.It is also found that subzero temperatures only limit the discharge potential of NCM622 without destroying its structure during cycling since it still exhibits high discharge capacity at 30℃after cycled at subzero temperatures.This work may expand the knowledge about the low-temperature characteristics of layered cathode materials for Li-ion batteries and lay the foundation for its further applications.     

Synthesis and Structural Characterization of a Di-nuclear Uranyl Complex with Quinoline-6-carboxylate

Crystallography Reports - A di-nuclear uranyl complex with the formula of [(UO2)2(L)4(H2O)2]?4H2O (1) (HL = quinoline-6-carboxylic acid) was synthesized hydrothermally and characterized by...     

The impact of asymptomatic individuals on the strength of public health interventions to prevent the second outbreak of COVID-19

Nonlinear Dynamics - The pandemic of coronavirus disease 2019 (COVID-19) has threatened the social and economic structure all around the world. Generally, COVID-19 has three possible transmission...     

卡维地洛印迹聚合物的合成及其识别性能的研究

以卡维地洛药物分子为模板,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,采用紫外光引发聚合的分子印迹技术,成功制备出卡维地洛分子印迹聚合物。用热重分析、扫描电镜对聚合物进行了表征,通过Scatchard方程研究了印迹聚合物对模板分子的结合特性。结果表明,在所研究的浓度范围内,印迹聚合物存在一类等价的结合位点,并计算出印迹聚合物与模板分子的平衡离解常数为0.5642 mmol/L,最大表观吸附量为97.44μmol/g,为理论值的63.53%。对不同底物的结合实验表明,该聚合物对卡维地洛具有优良的吸附选择性。