利用光栅最小偏向角法测光波波长

本文导出斜入射时,光栅谱线存在最小偏向角的条件及最小偏向角与波长间的关系,据此精确测定了光波波长,并在实验中通过与垂直入射法的比较显出其优越性。     

A guide to use fluorinated aromatic bulky cations for stable and high-performance 2D/3D perovskite solar cells: The more fluorination the better?

While serious stability issues impede the commercialization of perovskite solar cells(PSCs),twodimensional(2 D) perovskites based on fluorinated bulky cations have emerged as more intrinsically stable materials.However,the influence of fluorination degree of the bulky aromatic cation on the performance of resulting PSCs has not been scrutinized.Here,2 D perovskites(FxPEA)2 PbI₄(x=1,2,3,5) are grown in situ on the surface of the three-dimensional(3 D) perovskite and demonstrate effecti...     

Design,Synthesis, and In Vitro and In Vivo Antifungal Activity of Novel Triazoles Containing Phenylethynyl Pyrazole Side Chains

A series of triazole derivatives containing phenylethynyl pyrazole moiety as side chain were designed, synthesized, and most of them exhibited good in vitro antifungal activities. Especially, compounds 5k and 6c showed excellent in vitro activities against C. albicans (MIC = 0.125, 0.0625 μg/mL), C. neoformans (MIC = 0.125, 0.0625 μg/mL), and A. fumigatus (MIC = 8.0, 4.0 μg/mL). Compound 6c also exerted superior activity to compound 5k and fluconazole in inhibiting hyphae growth of C. albicans and inhibiting drug-resistant strains of C. albicans, and it could reduce fungal burdens in mice kidney at a dosage of 1.0 mg/kg. An in vivo efficacy evaluation indicated that 6c could effectively protect mice models from C. albicans infection at doses of 0.5, 1.0, and 2.0 mg/kg. These results suggested that compound 6c deserves further investigation.     

Cations Modulated Assembly of Triol-Ligand Modified Cu-Centered Anderson-Evans Polyanions

Counter-cations are essential components of polyoxometalates (POMs), which have a distinct influence on the solubility, stabilization, self-assembly, and functionality of POMs. To investigate the roles of cations in the packing of POMs, as a systematic investigation, herein, a series of triol-ligand covalently modified Cu-centered Anderson-Evans POMs with different counter ions were prepared in an aqueous solution and characterized by various techniques including single-crystal X-ray diffraction. Using the strategy of controlling Mo sources, in the presence of triol ligand, NH₄⁺, Cu²⁺ and Na⁺ were introduced successfully into POMs. When (NH₄)₆Mo₇O₂₄ was selected, the counter cations of the produced POMs were ammonium ions, which resulted in the existence of clusters in the discrete state. Additionally, with the modulation of the pH of the solutions, the modified sites of triol ligands on the cluster can be controlled to form δ- or χ-isomers. By applying MoO₃ in the same reaction, Cu²⁺ ions served as linkers to connect triol-ligand modified polyanions into chains. When Na₄Mo₈O₂₆ was employed as the Mo source to react with triol ligands in the presence of CuCl₂, two 2-D networks were obtained with {Na₄(H₂O)₁₄} or {{Na₂(H₂O)₄} sub-clusters as linkers, where the building blocks were δ/δ- and χ/χ-isomers, respectively. The present investigation reveals that the charges, sizes and coordination manners of the counter cations have an obvious influence on the assembled structure of polyanions.     

Responses of Issatchenkia terricola WJL-G4 upon Citric Acid Stress

This study aimed to elucidate the responses of a novel characterized Issatchenkia terricola WJL-G4 against citric acid stress by performing physiological analysis, morphology observation, and structural and membrane fatty acid composition analysis. The results showed that under citric acid stress, the cell vitality of I. terricola WJL-G4 was reduced. The cell morphology changed with the unclear, uncompleted and thinner cell wall, and degraded the cell structure. When the citric acid concentration was 20 g/L, I. terricola WJL-G4 could tolerate citric acid and maintain the cell structure by increasing the intracellular pH, superoxide dismutase activity, and contents of unsaturated fatty acids. As the citric acid concentration was ≥80 g/L, the stress has exceeded the cellular anti-stress ability, causing substantial cell damage. The cell membrane permeability, the content of membrane lipids, malondialdehyde and superoxide anion increased, but the intracellular pH and superoxide dismutase activities decreased, accompanying the increase of citric acid concentrations. The findings of this work provided a theoretical basis for the responsive mechanism of I. terricola WJL-G4 under high concentrations of citric acid, and can serve as a reference for biological acid reduction in fruit processing.     

抛光粉颗粒度对高功率激光玻璃材料抛光效率和粗糙度的影响

磷酸盐钕玻璃、熔石英和BK7是3类用于激光惯性约束聚变(ICF)装置主要光学元件材料.实验中采用不同平均粒径的氧化铈抛光粉对上述3类材料分别进行抛光,对特定材料抛光去除量和抛光粉平均粒径的关系进行了研究.实验表明:由于材料的物理和化学特性不同,特定的材料需选用相应平均粒径大小的抛光粉才能达到最佳的抛光效率.实验还就上述3类高功率激光玻璃材料抛光中各个阶段的抛光粗糙度与抛光粉平均粒径的关系进行了研究,结果表明:某一规格抛光粉的粒径对不同特性材料抛光后的表面粗糙度影响表征情况不同.     

Monoterpenoid Indole Alkaloids with Promoting Neurite Growth from Tabernaemontana divaricata

Main observation and conclusion Phytochemical investigations on Tabernaemontana divaricata led to the isolation of seven undescribed monoterpenoid indole alka-l...     

基于FDTD的时域混合方法及其在天线前门耦合数值模拟中的应用

强电磁脉冲环境下的平台-机载天线一体化耦合计算属于典型多尺度时域电磁计算问题,采用传统的FDTD方法数值模拟时,由于精细结构的存在导致网格量巨大,计算效率低下。介绍了一种将非均匀FDTD方法与细导线FDTD方法以及多网格集总元件FDTD方法相结合的时域混合方法,能够有效降低计算开销,结合并行计算技术,快速计算得到天线端口上耦合产生的瞬态电压和电流响应,并将该方法成功应用于无人机平台-天线一体化前门耦合数值模拟中。     

MOS结构电离辐射效应模型研究

基于氧化层空穴俘获和质子诱导界面陷阱电荷形成物理机制的分析,分别建立了MOS结构电离辐射诱导氧化层陷阱电荷密度、界面陷阱电荷密度与辐射剂量相关性的物理模型.由模型可以得到,在低剂量辐照条件下辐射诱导产生的两种陷阱电荷密度与辐射剂量成线性关系,在中到高辐射剂量下诱导陷阱电荷密度趋于饱和,模型可以很好地描述这两种陷阱电荷与辐射剂量之间的关系.最后讨论了低剂量辐照下,两种辐射诱导陷阱电荷密度之间的关系,认为低辐射剂量下两者存在线性关系,并用实验验证了理论模型的正确性.该模型为辐射环境下MOS器件辐射损伤提供了更 关键词： MOS结构 辐射 界面陷阱 氧化层陷阱     

Enhanced cyclability of sulfur cathodes in lithium-sulfur batteries with Na-alginate as a binder

Na-alginate as a binder in an aqueous solvent has been applied in the preparation of sulfur cathodes for lithium-sulfur batteries.Their electrochemical performances have been investigated by a charge-discharge cycle test and electrochemical impedance spectroscopy (EIS).The EIS tests indicated that the alginate sulfur cathode had lower resistance and better kinetic characteristics than those of the poly (vinylidene fluoride) (PVDF) sulfur cathode using PVDF as a binder in a N-methy-2-pyrrolidone (NMP) solvent.The charge-discharge tests showed that the discharge capacity and the capacity retention rate of Na-alginate sulfur cathode were 508 mAh·g-1and 65.4% at the 50th cycle with a current density of 335 mA·g-1.Compared with PVDF sulfur cathode,the alginate sulfur cathode showed a remarkably better cycle performance.These results show that the alginate binder has promising potential for lithium-sulfur battery applications.