Novel conductive metallo-supramolecular polymer AIE gel for multi-channel highly sensitive detection of hydrazine hydrate

Hydrazine hydrate(DH)is an important fine chemical intermediate and as fuel for rockets,however,it also has serious toxic for humans and environment.Developing novel materials and methods for sensitive detection of DH in water and air is an important task.In order to effectively detect DH,a novel conductive supramolecular polymer metallogel(PQ-Ag)has been constructed by the coordination of bis-5-hydroxyquinoline functionalized pillar[5]arene(PQ5)with Ag+.The metallogel PQ-Ag could realize the multi-channel sensitive detection of DH through naked-eye,fluorescence,and electrochemical methods.The lowest limit of detection(LOD)is 0.1 mg/m^(3)in air and 2.68×10^(−8)mol/L in water,which is lower than the standard of the US Environmental Protection Agency(EPA)for DH of maximum allowable concentration in drinking water.More importantly,an electronic device for DH detection based on the metallogel PQ-Ag was designed and prepared,which can realize conveniently and efficiently multi-channel detection and alert of DH through sound and light alarms not only in water but also in air.

Influence of lactic acid bacteria on physicochemical indexes,sensory and flavor characteristics of fermented sea buckthorn juice

Sea buckthorn has been proved to be a good substrate for lactic acid bacteria(LAB),but the research on the fermentation of sea buckthorn juice(SBJ)by LAB is still rare.This study was designed to determine the performance of fermented SBJ(FSBJ)in four LAB and investigate the sensory aspects of FSBJ.The results showed that the utilization rates of reducing sugar,titratable acid,and malic acid of SBJ fermented by Lactobacillus casei(SBJLc)were the highest and that lactic acid content was the greatest.The organic acid compositions of the four kinds of FSBJs were also different.The viable counts of all FSBJs was greater than 7 log CFU/mL,and that the viable count of SBJ fermented by SBJLc was the highest.In this study,the Electronic tongue combined with Electronic nose was used for the first time to study SBJ.Results showed that compared with the control,the response value of Sourness was significantly increased,while Bitterness and Astringency were significantly decreased.There was a significant difference in four FSBJs.The results of the electronic nose showed that SBJ fermented by Lactobacillus plantarum LP56(SBJLp)could be well identified by sensors sensitive to aromatic substances.The volatile compound contents before and after fermentation were significantly different,the highest being SBJLp.Finally,the results of sensory evaluation experiments showed that SBJLp was the most acceptable to consumers in terms of sensory evaluation.