Z-scheme CuFe2O4–TiO2 nanocomposite microspheres for the photodegradation of methylene blue

Research on Chemical Intermediates - The design and synthesis of effective photocatalysts for photodegradation of persistent organic pollutants is of significant importance. Novel CuFe2O4...     

Synthesis,structure and property of diorganotin N‐[(3‐methoxy‐2‐oxyphenyl)methylene]tyrosinates

Five new diorganotin N‐[(3‐methoxy‐2‐oxyphenyl)methylene] tyrosinates, R₂Sn[2‐O‐3‐MeOC₆H₃CH=NCH (CH₂C₆H₄OH‐4)COO] (R = Me, 1 ; Et, 2 ; Bu, 3 ; Cy, 4 ; Ph, 5 ), have been synthesized and characterized by elemental analysis, IR, NMR (¹H, ¹³C and ¹¹⁹Sn) spectra, and the X‐ray single crystal diffraction. In non‐coordinated solvent, complexes 1 – 5 have penta‐coordinated tin atom. In the solid state, 1 – 3 are centrosymmetric dimmers in which each tin atom is seven‐coordinated in a distorted pentagonal bipyramid, and 4 displays discrete molecular structure with distorted trigonal bipyramidal geometry, and the tin atom of 5 is hexa‐coordinated and possess the distorted octahedral geometry with a coordinational methanol molecule. The intermolecular O‐H???O hydrogen bonds in 1 – 4 link molecules into the different one‐dimensional supramolecular chain with R₂² (30) or R₂² (20) macrocycles, and the molecules of 5 are joined into a two‐dimensional supramolecular network containing R₄⁴ (24) and R₄⁴ (28) two macrocycles. Bioassay results against human tumour cell HeLa indicated that 3 ‐ 5 belonged to the efficient cytostatic agents and the activity decreased in the order 4 > 3 > 5 > 2 > 1. The fluorescence determinations show the complexes may be explored for potential luminescent materials.     

Enhancement of chloroform degradation by the combination of hydrodynamic and acoustic cavitation

The decomposition of chloroform by the combination of hydrodynamic and acoustic cavitation (Hydrodynamic-Acoustic-Cavitation/HAC) has been investigated. The flow rate and the hole diameter of the orifice plate remarkably affect the conversion of chloroform in the combined system. The conversion increases with increasing fluid velocity without any restriction. With a 2.8mm orifice plate the conversion reaches an optimal value. A synergistic effect has been obtained by the hybrid method of acoustic and hydrodynamic cavitation. The total synergistic effect achieves 17% and 73% per pass, respectively. The analysis of the energy efficiencies shows different results. Due to high optimization potential, this hybrid method can be visualized as a new step for wastewater treatment.     

Extracting the mechanisms and kinetic models of complex reactions from atomistic simulation data

Determining reaction mechanisms and kinetic models, which can be used for chemical reaction engineering and design, from atomistic simulation is highly challenging. In this study, we develop a novel methodology to solve this problem. Our approach has three components: (1) a procedure for precisely identifying chemical species and elementary reactions and statistically calculating the reaction rate constants; (2) a reduction method to simplify the complex reaction network into a skeletal network which can be used directly for kinetic modeling; and (3) a deterministic method for validating the derived full and skeletal kinetic models. The methodology is demonstrated by analyzing simulation data of hydrogen combustion. The full reaction network comprises 69 species and 256 reactions, which is reduced into a skeletal network of 9 species and 30 reactions. The kinetic models of both the full and skeletal networks represent the simulation data well. In addition, the essential elementary reactions and their rate constants agree favorably with those obtained experimentally. © 2019 Wiley Periodicals, Inc.     

基于超高效液相色谱-四极杆飞行时间质谱联用技术的血瘀模型大鼠血浆代谢组学分析

采用盐酸肾上腺素加冰水浴建立急性血瘀大鼠模型，使用超高效液相色谱-四极杆飞行时间质谱（UPLC-Q-TOF/MS）检测空白对照组与血瘀模型组中血浆代谢物，用主成分分析（PCA）、有监督偏最小二乘法判别分析（PLS-DA）及正交偏最小二乘法判别分析（OPLS-DA）对代谢组学数据进行多维统计分析，筛选潜在生物标志物。与对照组相比，在血瘀模型组大鼠血浆中检测出46个差异代谢物，血瘀模型组中乙酰胆碱、N6，N6，N6-三甲基-L-赖氨酸、胞嘧啶、乙酰肉碱等21个代谢物显著上调，吲哚丙酸、LysoPC（14：0）等25个代谢物显著下调，可能与脂质代谢、半乳糖代谢、亚油酸代谢、不饱和脂肪酸生物合成、糖酵解、花生四烯酸代谢等通路有关。代谢产物可作为血瘀证研究中的重要标记物，该研究结果有助于揭示血瘀证的发病机制，可为临床血瘀疾病的诊断及选用药物治疗提供思路，为后续治疗手段提供参考依据。     

异质中空结构微纳材料的构建

异质中空结构是指壳层由不同成分组成的空心微纳结构. 通过对异质中空结构的表面性质和传质过程进行调控, 可以调控经过中空结构的物质及能量. 目前, 异质中空结构在太阳能转化、 气体传感、 电化学储能和药物运输等领域展示出了优异的性能, 对异质中空结构的设计与构建已成为新型多功能先进材料研究的前沿领域. 本文总结了异质中空结构的种类、 特征和性能优势, 重点描述了各类异质中空结构的制备方法, 并探讨了异质中空结构微纳材料面临的挑战及发展趋势.     

Microbe removal using a micrometre-sized optical fiber

The growing global shortage of fresh water has lead to the need for technological innovations for water purification and reuse. The removal of pathogenic microbes from urban, laboratory or industrial wastewater is one of the most challenging and critical issues due to the potential risk of microbe outbreaks. In addition, microbe removal in human blood or tissues has also inspired novel techniques for extracting and collecting different cells in fluidic channels or vessels. Recently, efficient removal of microbes from flowing water running under gravity feed has been achieved using filters in nanotubes or nanofibers. Here we report a highly efficient removal of microbes from flowing water in a fluidic channel using a reusable micrometre-sized optical fiber. Our technique is based on photophoresis of the microbes induced by the radiation of 1.55 μm wavelength injected into the fiber. Yeast cell suspensions, as a sample of microbe-contaminated water, are flown through a fluidic channel and the suspended cells are collected by the photophoretic forces, leading to a consistent accumulation of the yeast cells. The experiments indicate that a removal efficiency of 99.9% can be obtained when the flow velocity of the suspensions is less than the peak photophoretic velocity of the yeast cells.     

Three New Phenol Compounds from Iris dichotoma Pall.

Three new phenolic compounds, irisdichototins D, E, and F ( 1 – 3 , resp.) were isolated from the stems of Iris dichotoma. The structures of the new compounds were elucidated by spectroscopic analyses, including 2D‐NMR techniques.     

火星探测器进入飞行气动测量方法研究

在火星探测任务的进入飞行过程中,开展气动测量将获取大量宝贵的气动特性数据,一方面可以验证进入探测器气动外形,掌握其准确的气动特性,另一方面,可以积累详实的火星大气数据,为后续任务提高落点精度等飞行性能提供支持. 本文针对火星探测器进入飞行任务,基于弹道重建和嵌入式大气数据传感系统(flushair data system, FADS),提出火星探测器进入飞行过程中的气动测量方法. 通过融合火星进入外测弹道信息,利用输出误差法实现攻角、侧滑角的高精度测量;基于嵌入式大气数据传感系统,利用最小二乘最优估计算法,建立了进入飞行动压的测量方法. 仿真分析表明,气动测量方案精度高,进入动压测量精度优于1%,攻角和侧滑角测量精度相较于当前火星探测器进入气动测量而言,至少提升1 个量级. 研究结果将为火星探测等深空探测任务的进入飞行气动测量提供技术参考.