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An efficient [4 + 1] annulation between α-bromooximes and sulfur ylides via in situ generation of nitrosoalkenes under mild basic reaction conditions has been developed, providing an expeditious and scalable approach to synthesize biologically interesting isoxazoline derivatives with good to excellent yields.

Graphene (graphene) is a new type of two-dimensional inorganic nanomaterial developed in recent years. It can be used as an ideal inorganic nanofiller for the preparation of polymer nanocomposites because of its high mechanical strength, excellent electrical conductivity and plentiful availability (from graphite). In this review, the preparation methods of graphene/polymer nanocomposites, including solution blending, melt blending and in situ polymerization, are introduced in order to study the relationship between these methods and the final characteristics and properties. Each method has an influence on the final characteristics and properties of the nanocomposites. The advantages and disadvantages of these methods are discussed. In addition, a variety of nanocomposites with different properties, such as mechanical properties, electronic conductivity, thermal conductivity and thermal properties, are summarized comprehensively. The potential applications of these nanocomposites in conductive materials, electromagnetic shielding materials, photocatalytic materials and so on, are briefly presented. This review demonstrates that polymer/graphene nanocomposites exhibit superior comprehensive performance and will be applied in the fields of new materials and novel devices. Future research directions of the nanocomposites are also presented.

A rapid and reproducible method has been developed for the simultaneous quantification of dopamine (DA), norepinephrine (NE), and serotonin (5-HT) in rat brain microdialysates. Derivatization was processed through reductive amination with butyraldehyde and sodium cyanoborohydride at 60℃ for 80 min incubation. Dibutylated monoamine neurotransmitters (MANTs) were directly analyzed with ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The chromatographic run time was shorter (2.1 min/sample) than previous studies [15] [18] [20]. Good linearity (R2 > 0.99) was obtained for DA, NE and 5-HT in the range of 25 - 5000 pg/mL, 5 - 1000 pg/mL and 2.5 - 500 pg/mL, respectively. Acceptable precision (CV, 8.5% - 13.4%) as well as accuracy (recovery, 94.1% - 106.8%) could be acquired by analysis of six batches of quality control samples (QCs) at four different concentrations, which demonstrated the reliability and reproducibility of current method. This method was successfully applied to the simultaneous determination of DA, NE and 5-HT in rat brain microdialysates, where basal levels as well as elevated levels after dosing with amphetamine (AMPH) were quantified for all three MANTs. This study provides a simple and rapid way to analyze MANTs in the biofluid in the future.

Compared to the aza-Wittig reaction of aldehydes, ketones, amides, and esters, the aza-Wittig reaction of acid anhydride was always overlooked, which should be an important part of Wittig reactions. Here, the aza-Wittig reaction of anhydride and catalytic aza-Wittig reaction of anhydride were both developed with high yields, which provides an efficient method to synthesize of 4H-benzo[d][1,3]oxazin-4-ones and 4-benzylidene-2-aryloxazol-5(4H)-ones. The strategy of copper-catalyzed reduction of phosphine oxide was used and found effective for this transformation. Additionally, the one-pot catalytic aza-Wittig reaction of carboxylic acids was achieved. Furthermore, NMR experiments and Hammett plot recorded the process of catalytic aza-Wittig reaction of anhydride, which provides direct proof that the copper-catalyzed reduction of waste phosphine oxide is the key step in this transformation.

It is necessary to carry out regular maintenance and replacement of the traditional power transformer pressure and humidity absorber in the long running time. When the transformer in use to upgrade or retrofit, usually need to find a simple, practical solution. Conventional moisture absorbers require the use of silica gel particles or similar desiccant to absorb water, the need for regular replacement of desiccant. In order to improve the working efficiency of desiccant and reduce the cost of desiccant replacement, this paper introduces the latest technology of dual-channel maintenance-free moisture absorber, describes the working principle of the device and the advantages of the element, and its application prospects in the power industry Outlook.

The present study was designed to highlight the impact of seed priming with polyethylene glycol on physiological and molecular mechanism of two cultivars of Oryza sativa L. under different levels of zinc oxide nanorods (0, 250, 500 and 750 mg L−1). Plant growth parameters were significantly increased in seed priming with 30% PEG under nano-ZnO stress in both cultivars. Whereas, this increase was more prominent in cultivar Qian You No. 1 as compared to cultivar Zhu Liang You 06. Significant increase in photosynthetic pigment with PEG priming under stress. Antioxidant enzymes activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) as well as malondialdehyde (MDA) contents were significantly reduced with PEG priming under nano-ZnO stress. Gene expression analysis also suggested that expression of APXa, APXb, CATa, CATb, CATc, SOD1, SOD2 and SOD3 genes were down regulated with PEG priming as compared to non-primed seeds under stress. The ultrastructural analysis showed that leaf mesophyll and root cells were significantly damaged under nano-ZnO stress in both cultivars but the damage was prominent in Zhu Liang You 06. However, seed priming with PEG significantly alleviate the toxic effects of nano-ZnO stress and improved the cell structures of leaf and roots in both cultivars.