Acid-promoted metal-free synthesis of 3-ketoquinolines from amines,enaminones and DMSO

A metal-free p-toluenesulfonic acid (TsOH·H₂O) mediated synthesis of 3-ketoquinolines from anilines, enaminones and DMSO has been developed. In this transformation, DMSO was activated by TsOH·H₂O and provided the one-carbon unit of the 3-ketoquinolines. A plausible mechanism involving an electrophilic sulfenium ion intermediate was proposed.     

Tandem reaction of heterocyclic ketene aminals with diazoesters: Synthesis of pyrimidopyrrolidone derivatives

A tandem reaction of heterocyclic ketene aminals (HKAs) with diazoesters in the presence of a Cu catalyst is demonstrated for the efficient synthesis of pyrimidopyrrolidone derivatives. The reaction shows a broad substrate scope and excellent functional group tolerance. Our method provides rapid access to diverse pyrimidopyrrolidones in moderate to excellent yields under mild reaction conditions.     

沉淀剂和Ag含量变化对甲醛降解性能的影响

采用不同沉淀剂制备CeO₂-Co₃O₄复合金属氧化物载体,通过浸渍负载不同含量Ag获得Ag/CeO₂-Co₃O₄催化剂.借助氮气物理吸附、XRD、Raman和H₂-TPR等手段研究了催化剂的物理化学性质.结果表明：当WHSV=30 000 mL·g^-1·h^-1时,催化剂能表现出良好的催化氧化甲醛性能,在≤ 90℃时实现甲醛的完全转化.草酸沉淀能有效降低Ce-Co氧化物的结晶度,使得Co²⁺含量增加,提供更多的氧空位,促进了氧分子的活化与迁移,从而提高了催化活性.随着Ag含量增加,使得由草酸沉淀制备的Ag/CeO₂-Co₃O₄催化剂的活性增强,且金属与载体间的相互作用也增强,当Ag负载量为1%（重量百分比）时活性最佳.     

A carbazole-hemicyanine dye based ratiometric fluorescent probe for selective detection of bisulfite (HSO3−) in cells and C. elegans

A colorimetric and ratiometric fluorescent probe for selective detection of HSO₃^- based on the 1,4-nucleophilic addition reaction was successfully synthesized and applied to the detection of exogenous HSO₃^- in Hela cells and C. elegans.     

Computational binding study of cardiac troponin I antibody towards cardiac versus skeletal troponin I

A computational study of the interaction of cardiac troponin I (cTnI) with its specific antibody and of that antibody with skeletal troponin I (sTnI), the principal interferon of cTnI, is carried out. Computational and simulation tools such as FTSite, FTMap, FTDock and pyDock are used to determine the binding sites of these molecules and to study their interactions and molecular docking performance, allowing us to obtain relevant information related with the antigen-antibody interaction for each of the targets. In the context of the development of immunosensing platforms, this type of computational analysis allows performing a preliminary in-silico affinity study of the available bioreceptors for a better selection when moving to the experimental stage, with the subsequent saving in cost and time.     

Spatio-temporal history of decay

The decay process of a metastable excited state is studied in this Letter. We have modeled the system as a particle of finite mass coupled to a continuum of excitations and it is found that the excitations move instantaneously in space. We discuss our observations in connection with Fermi's two atom problem and Hegerfeldt's theorem. Our observations confirm Hegerfeldt's theorem for an exactly solvable and experimentally realizable model.     

Anti-Staphylococcus aureus evaluation of gallic acid by isothermal microcalorimetry and principle component analysis

Journal of Thermal Analysis and Calorimetry - The emergence of antibiotic-resistant Staphylococcus aureus requires new antibacterial drugs. In this study, using a thermal activity monitor air...     

A modified Artificial Bee Colony algorithm for structural damage identification under varying temperature based on a novel objective function

This paper presents a modified Artificial Bee Colony algorithm for structural damage identification. Meanwhile, the effect of temperature variation is considered and the change of temperature will lead to the alteration of Young's modulus of material. A novel objective function is proposed as the combinations of the partial mode shape curvature data, alterations of natural frequencies, and a sparse penalty term. Such an objective is found to be sensitive to structural damage while not sensitive to environmental effects. On the other hand, To render the standard Artificial Bee Colony algorithm more powerful and robustness, two local search strategies are introduced into the employed and onlooker bee phase of the Artificial Bee Colony algorithm, respectively. Two numerical examples and a laboratory verification are employed to verify the efficiency and advantage of the proposed algorithm. The final results show that the present algorithm could yield more satisfactory identification results compared with other state-of-the-art evolutionary algorithms, even high-level noise and temperature variation are considered; and the proposed novel objective function is more sensitive to structural damages, compared with the traditional mode-shape-based objective function.     

Chamigrane Sesquiterpenes from Cultures of Fungus Antrodiella albocinnamomea

Chemistry of Natural Compounds - A new chamigrane sesquiterpene, antroalbol F (1), along with one known compound, acaciicolinol C (2), were isolated from cultures of the fungus Antrodiella...     

团体随机和择优混合演化网络模型的稳定性

主要通过马氏链、主方程的方法和技巧,给出了团体随机和择优混和演化网络的稳态度分布存在性的严格证明,并严格推导了度分布的精确解析表达式.