L-proline catalyzed multicomponent domino reaction in polyethyleneglycol-400 for regioselective synthesis of pyrazolyl-tetrahydroindazolones under microwave irradiation

A simple and convenient approach for the synthesis of pyrazolyl-tetrahydroindazolones via L-proline catalyzed three component domino reaction of arylhydrazine, dimedone and pyrazole aldehyde in polyethyleneglycol-400 (PEG-400) under microwave irradiation is described. This novel and green protocol proceeds smoothly in good to excellent yields and provides several advantages such as shorter reaction time, metal-free reaction conditions, simple work-up procedures. Also, recycling of the catalyst and solvent was observed without the loss of activity for three (03) runs.     

Synthesis of homo-propargylic ethers: A domino ring opening/coupling reaction of oxiranes with terminal alkynes and aryl iodides

A domino ring opening/cross-coupling reaction of oxiranes with terminal alkynes and aryl iodides has been developed. This transformation serves as a protocol for the synthesis of homo-alkyne ether skeletons from the readily available starting materials. The success of the reaction has dependence on catalyst/ligand system of choice. The synthesis utility of the alkyne ether skeletons in formation of chromane skeleton has also been studied.     

400 kV高压脉冲变压器设计与仿真

400 kV高压脉冲变压器波形仿真利用了脉冲变压器工作模型,文中给出了分布参数的估算和主要参数的计算方法。为了满足脉冲变压器的波形要求和耐压需要,减少分布参数对其影响,对铁芯结构和均压环进行了优化设计。根据调整后的参数,利用Spice软件,对脉冲变压器进行了波形仿真,结果表明,仿真波形的主要参数和计算结果一致,可满足指标要求。     

A green and efficient method for synthesis of benzimidazoles using nano‐Fe3O4 in PEG‐400/H2O aqueous system under ambient conditions at room temperature

In this paper, a green and facile protocol was described which was efficient for synthesis of benzimidazoles using nano‐Fe₃O₄ catalyst with continuous bubbling of air as the oxidant in PEG‐400/H₂O aqueous system at room temperature. This protocol afforded the target products in good to excellent yields and the catalytic system could be recycled and reused without significant loss of catalytic activity. Copyright © 2014 John Wiley & Sons, Ltd.     

Sensitized multiphoton dissociation of UF6 IN SF6-UF6 mixtures by a tea CO2 laser

UF₆ undergoes decomposition in the presence of SF₆ when mixtures of both are irradiated with a TEA CO₂ laser. The mechanism for UF₆ decomposition may involve vibrational energy transfer from excited SF₆ and laser absorption from the same laser pulse by excited UF₆ in its vibrational quasi-continuum     

Facile one-step sonochemical synthesis of ultrafine and stable fluorescent C-dots

This work describes a one-step synthesis of carbon dots (C-dots), which is carried out by sonication of polyethylene glycol (PEG-400) for 0.5–3 h. The effect of the various experimental parameters, such as sonication time, amplitude and temperature on the size and the fluorescence of the C-dots was studied. It was found that the average diameter of the C-dots is between 2 and 9 nm, depending on the preparation conditions. The highest quantum yield of emission was ∼16%. These high fluorescence properties of the C-dots could be used for bioimaging and for solar cell applications.     

A rapid,mild, and efficient method for C-5 iodination/thiocyanation of 2-aminothiazoles

An efficient, green, rapid multitasking protocol for the selective C-5 substitution of 2-aminothiazole using iodic acid and aqueous PEG-400 was developed. The method found suitable for C-5 substitution i.e. iodination and thiocyanation of 2-amino thiazole using iodine and ammonium thiocyanate respectively. Iodic acid was found to be a good oxidant and aqueous PEG-400 as green reaction solvent.     

S400β模式1394B总线接口单元设计与实现

新一代航空电子系统大量采用分布式智能终端,大容量、高速、实时图像数据成为其显著特征。IEEE 1349B是广泛应用的高速串行总线,具有传输速率高、可靠性好、扩展性强的优点,是目前实现数字图像及视频传输的首选方案之一。文章基于PCI架构设计出S400β模式的1349B总线接口单元。基于Vxworks操作系统开发出了该接口单元的驱动和主机PCI接口驱动开发。通过1394B总线标准测试设备的验证,该接口单元可以实现400Mb/s的高速数据实时传输,证明了该接口单元的可行性和可靠性,对嵌入式高速IO设计具有参考价值。     

A green protocol for one pot synthesis of benzosuberone tethered thiadiazolopyrimidine-6-carboxylates using PEG-400 as potent anti-proliferative agents

A new concise and facile method was explored to synthesize a collection of new benzosuberone based thiadiazolo [3,2-a] pyrimidine-6-carboxylates using polyethylene glycol (PEG), which could be regarded as the derivatives of the hybrid scaffolds of bioactive natural benzosuberone and heterocyclic thiadiazolo[3,2-a]pyrimidine. The structures of the synthesized compounds were characterized by ¹H, ¹³C NMR, MS and IR; and their anti-proliferative activity was evaluated against four human cancer cell lines; A549, SKNSH, HeLa and MCF-7. Among the tested compounds, compound 8k showed the most prominent activity against all the cell lines and these results may lay the foundation for further design of novel anti-proliferative agents.     

Crack bridging mechanism for glass strengthening by organosilane water-based coatings

We used an epoxysilane/aminosilane coating deposited from an aqueous solution to strengthen flat glass. We studied film formation, interfacial and mechanical properties of the film. The film is highly cross-linked with a 6 GPa Young’s modulus and good adhesion. Our results suggest that crack face bridging accounts for most of the 75% reinforcement in this system.