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Using the aldehyde amine condensation procedure and the triphenylamine group as the skeleton structure, the new triphenylamine-aromatic aldehyde-succinylhydrazone probe molecule DHBYMH was created. A newly created acylhydrazone probe was structurally characterized by mass spectrometry (MS), NMR, and infrared spectroscopy (FTIR). Fluorescence and UV spectroscopy were used to examine DHBYMH’s sensing capabilities for metal ions. Notably, DHBYMH achieved a detection limit of 1.62 × 10−7 M by demonstrating exceptional selectivity and sensitivity towards Cu2+ ions in an optimum sample solvent system (DMSO/H2O, (v/v = 7/3); pH = 7.0; cysteine (Cys) concentration: 1 × 10−4 M). NMR titration, high-resolution mass spectrometry analysis, and DFT computation were used to clarify the response mechanism. Ultimately, predicated on DHBYMH’s reversible identification of Cu2+ ions in the presence of EDTA, a molecular logic gate was successfully designed.

In order to explore the composition of main volatile compounds and the difference of aroma compounds in Sauce-flavor Baijiu with different sweet flavor characteristics, sensory evaluation method was used to select Sauce-flavor Baijiu samples, the volatile components were analyzed by headspace solid phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS), and partial least squares discriminant analysis (PLS-DA) was used to analyze different Baijiu samples and their flavor differences substances. The results showed that the samples were divided into three groups, and the intensity values of sweet-flavor in each group were 4.0~5.0, 3.0~4.0 and 0.0~3.0, respectively, and a total of 68 volatile flavor compounds were characterized, including 27 esters, 12 alcohols, 10 aldehydes and ketones, 3 acids, 10 aromatics and 6 terpenes, among them, esters, aromatics and alcohols with sweet and fruity aromas were the three most abundant types of compounds in different Baijiu samples, and the content was the highest in Baijiu samples with a sweet flavor intensity greater than 3.0, indicating that these three types of substances had an important impact on the flavor characteristics of sweet aroma. There were 25 potential difference compounds affecting the three groups of Baijiu samples, and the related sweet flavor markers were mainly 3-methyl butanol, ethyl octanoate, isobutyl lactate and ethyl phenylacetate, indicating that these substances were the important aroma compounds that cause differences between different sauce-flavor Baijiu samples with different sweet flavor characteristics.

Vanillin is a very important aroma compound in alcoholic beverages. It has been widely concerned because of its pleasant sweet aroma, vanilla aroma and physiological function. Vanillin has strong polarity and trace in alcoholic beverage, so conventional detection methods are difficult to effectively detect the content of vanillin in alcoholic beverage. Therefore, exploring the analysis method of vanillin in alcoholic beverage has always been a research topic. The cell wall of the raw and auxiliary materials of alcoholic beverage is rich in lignin and ferulic acid, which is an important precursor for the formation of vanillin. It can be converted into vanillin in the brewing process through metabolic pathways such as non oxidative decarboxylation reaction of fungi, bacteria and other microorganisms. In this paper, analytical method, aroma contribution, different content and formation mechanism of vanillin in alcoholic beverage are reviewed, which can provide theoretical reference for the research of vanillin in alcoholic beverage.

In this paper, functionalized sodium alginate hydrogel (FSAH) was prepared to efficiently adsorb heavy metals and dyes. Hydrazide-functionalized sodium alginate (SA) prepared hydrazone groups to selectively capture heavy metals (Pb2+, Cd2+, and Cu2+), and another functional group (dopamine grafting), serves as sites for adsorption methylene blue (MB), malachite green (MG), crystal violet (CV). Thermodynamic parameters of adsorption indicated that the adsorption process is endothermic and spontaneous. The heavy metals adsorption by FSAH was physical adsorption mainly due to ΔHθ < 40 kJ/mol, and the adsorption of cationic dyes fitted with the Langmuir models, which indicated that the monolayer adsorption is dominated by hydrogen bonds, electrostatic interactions, and π-π interactions. Moreover, the adsorption efficiency maintained above 70% after five adsorption-desorption cycles. To sum up, FSAH has great application prospect.

This essay studies a novel environment-friendly synthesis method for the high purity micron iron phosphate. Compared with traditional synthesis method, this new method can greatly reduce the amount of industrial sewage, hence it is an environment-friendly production technology which can effectively improve the products’ purity, structure stability and morphological consistency. This new method includes two-step reactions: first, phosphoric acid, iron powder and hydrogen peroxide are used as raw materials to obtain iron phosphate dihydrate intermediate, which is then calcined at high temperature to obtain anhydrous iron phosphate. The results show that the iron phosphate prepared for this new method is a hexagonal system-structured iron orthophosphate with high purity and without any impurities, exhibiting a regular and primary spherical particle morphology, at the average size of 3.096 μ m in particle and the specific surface area reaching 39.1765 m ^2 g ^−1 . With these excellent characteristics, it has better application potentials in the field of electrode material preparation. The electrochemical performance of lithium iron phosphate anode materials synthesized with it as the precursor is superior to those synthesized with the iron phosphate prepared by the traditional method as precursor. The first specific capacity of discharge at 0.5C and 10C can be as high as 154.3989 or 102.9326 mAh g ^−1 , increasing by 2.74% and 8.03%, respectively.

A new isoflavan, named dalbergiacochan A (1), was isolated from the heartwood of Dalbergia cochinchinensis, along with two known isoflavans, namely mucronulatol (2) and 2′ -O-methylsepiol (3). Their structures were elucidated based on extensive spectroscopic analyses, including one-dimensional (1D) and two-dimensional nuclear magnetic resonance (2D NMR), and mass spectroscopy (MS) data, and the absolute stereochemistry of compound 1 was determined as R-3′,6-dihydroxy-2′,4′,8-trimethoxyisoflavan from its circular dichroism spectrum. Compound 1 was inactive against Escherichia coli, Bacillus thuringiensis, and Shigella dysenteriae. [ABSTRACT FROM AUTHOR]

The release of ferulic acid (FA) and the subsequent enzymatic decarboxylation to 4-vinylguaiacol (4-VG) were nearly ubiquitous during the production of Chinese rice wine. To evaluate the release of FA and the transformation to 4-VG, the levels of FA and 4-VG were determined by high performance liquid chromatography (HPLC) and gas chromatography-mass spectrum (GC- MS), respectively. During rice wine brewing, the concentrations of FA and 4-VG increased as fermentation time prolonged, with a rapid rise in days 1 to 5 of the main fermentation and followed by a slower rise from the 6th day post inoculation. FA and 4-VG levels in mashes, fermented by yeast with wheat Qu, were significantly higher than those in mashes fermented by yeast using commercial enzyme additions. The release of FA from rice by wheat Qu involves an enzymatic release mechanism. The levels of FA and 4-VG from rice flour by wheat Qu rose gradually during the first 24 h and then tended to stabilize. The capacity of yeasts to decarboxylate phenolic acids (Pof+ phenotype) was absent in most rice wine brewing yeasts. These results suggest that the production of FA and 4-VG originated from materials in the wheat Qu rather than by the yeast during Chinese rice wine brewing and fermentation. [ABSTRACT FROM AUTHOR]