The presence of metronidazole (MNZ) residues in food poses significant risks to human health. In this study, two metal-organic framework (MOF)-based fluorescent probes, [Ba(bbda)]n (1) and [Cd(bbda)]n (2), were developed for the rapid and ultrasensitive detection of MNZ in food samples. Upon addition of MNZ, both probes exhibited significant fluorescence quenching with favorable linear ranges and low detection limits of 37 nM and 64 nM, respectively. Fluorescence lifetime and density functional theory (DFT) calculations revealed that the quenching mechanism involves a synergistic effect of the inner filter effect (IFE), photoinduced electron transfer (PET), and specific ligand-analyte interactions. Probe 1 was successfully applied to quantify MNZ in commercial pharmaceutical tablets and milk powder, achieving excellent recoveries of 97% and 102.6%, respectively, demonstrating its reliability for trace-level MNZ detection in food matrices.

High selectivity detection and fast response for Sparfloxacin (Spa) is always a challenge. In this paper, two new coordination polymers [InCl(PPA)(H2O)]n & sdot;nH2O (1) and [La(PPA)(ox)1/2(H2O)]n(2). (H2PPA = 3-(pyridin-3yloxy)phthalic acid, H2ox = oxalic acid) were synthesized by hydrothermal method and analyzed in depth by Xray single crystal diffraction, elemental analysis, IR spectroscopy, PXRD and thermogravimetric analysis. Both compounds 1 and 2 display 2D layered structures. Notably, these two compounds behave as fluorescent sensors toward Spa with high sensitivity, selectivity with low detection limits of 18.16 and 48.17 nM, respectively. The present work investigated the mechanism of fluorescence enhancement by Spa for both compounds, which may be the result of the interaction between Spa and ligand. It is worth noting that for the first time, the coordination polymer was established to detect Spa by fluorescence sensing method.

The abuse of antibiotics has triggered the rise of drug-resistance bacteria, which has seriously threatened public health globally. Herein, a novel lanthanide metal-organic framework (Ln-MOF) fluorescence sensor, [Eu(atpa)(hz)1/2(H2O)]n (1), (H3atpa = 4-(1H-tetrazol-5-yl)phthalic hydrazide, hz = hydrazine) was solvothermally synthesized via an in situ acylation reaction between H₃tpa and hydrazine hydrate in the presence of Eu(III). Single-crystal X-ray diffraction analysis reveals that 1 displays a 3D coordination network structure, where the Eu(III) centers and hz ligands interconnect to form a pentagonal bipyramidal geometry. Remarkably, 1 functions as a stable dual-emission ratiometric fluorescence sensor under ambient conditions (room temperature, pH = 5) and demonstrates exceptional selectivity and sensitivity toward Nitrofurazone (NF) and Oxytetracycline (OTC), with low limit of detection (LOD = 61.72 nM for NF and LOD = 57.76 nM for OTC). Mechanistic studies combining UV-Vis and XPS analyses revealed that the fluorescence quenching of 1 at 650 nm arises from the synergistic effects of the inner filter effect (IFE) and 1-analyte interactions. Density functional theory (DFT) calculations further confirmed the absence of photoinduced electron transfer (PET). Additionally, fluorescence lifetime measurements ruled out Förster resonance energy transfer (FRET) and PET as possible quenching mechanisms.

In this study, the Box-Behnken design model was used to plan the experiment, and the corresponding model was constructed using Design-Expert software. Using this model, the interaction of various factors in the treatment of high-concentration ammonia nitrogen wastewater using bubble discharge plasma was investigated. Response surface model analysis and regression equation significance tests were conducted to optimize the treatment conditions for high-concentration ammonia nitrogen wastewater treated by plasma. Based on the single-factor test results, voltage, frequency, and air pressure were selected as the influencing factors; the removal rate of ammonia nitrogen was taken as the target value; and the response surface was analyzed. The results revealed the influence of the interaction between these factors on the removal rate of ammonia nitrogen and determined the optimal reaction conditions: voltage 12.1 kV, frequency 165.9 Hz, and pressure 0.01 MPa; under these conditions, the 50 min treatment rate of ammonia nitrogen reached 99.14%. Subsequently, these conditions were validated, and their high efficiencies were demonstrated through degradation kinetics.

A cheap and green method for porous carbons (CAC-1) with high surface area (409.41 mg/g) is constructed benefiting from self-healing properties of calcium alginate hydrogel under atmospheric drying. Layered double hydroxides modified CAC-1 (CAC-LDH-1) is applied in cadmium-arsenic complex pollution. The adsorption capacities of the CAC-LDH-1 on Cd(II) and As(V) are 331.03 mg/g and 33.48 mg/g in single system, and 79.87 mg/g and 150.59 mg/g in binary system. In binary system, the synergistic action of Cd(II) ions greatly improve the adsorption capacity and adsorption rate of As(V) ions. The adsorption process of cadmium-arsenic by CAC-LDH-1 mainly follows the second-order kinetic model and Freundlich model, and the adsorption process is endothermic and spontaneous. XPS, FTIR, XRD, SEM-EDS mapping and pore size distribution are carried out to explore the structure and adsorption mechanism of CAC-LDH-1. After treatment with 1 % CAC-LDH-1 for 30 days, the proportions of E1-Cd, F1-As, and F2-As that can be utilized by plants decrease from 46.32 % to 33.15 %, 10.08-2.15 %, and 43.06-35.23 %. Compared with CK group, Cd/As contents in the above/under-ground part of red cherry radish seedlings decrease by 31.41 similar to 59.09 %. CAC-LDH-1 inhibits little effect on the microbial diversity of soil, but change the dominant bacterial colonies.

This study presents a simple method for treating NH3-N wastewater using bubble discharge plasma and introduces a wastewater treatment system. The impacts of pH, voltage, pulse frequency, and reaction time on the treatment of NH3-N wastewater were investigated using simulated wastewater samples. The concentrations of NH3-N, total N, and by-products were measured using ultraviolet spectrophotometry. Results indicate that NH3-N was more easily oxidised by the reactive species generated in an alkaline environment. The generated •OH were captured using salicylic acid. Increasing the voltage and discharge frequency promoted •OH generation, thereby facilitating the NH3-N removal through oxidation reactions. The effect of the plasma was verified by a quenching experiment, and the optimal reaction efficiency was achieved at a pH of 12, voltage of 12 kV, and pulse frequency of 160 Hz. The NH3-N removal rate reached 99.14% after 50 min of treatment; hence, the wastewater treatment was successful.

Two new coordination polymers [M(L)(H2O)2]n (M=Co (1) and Mn (2)) (H2L=5-(pyrazin-2-yl) isophthalic acid) were synthesized by hydrothermal method and systematically characterized. The two compounds were analyzed in depth by x-ray single crystal diffraction, elemental analysis, IR spectroscopy, PXRD and thermal analysis. The x-ray single crystal diffraction results indicate that compound 1 is a 3D framework structure. Through the carboxyl oxygen atoms and pyrazine nitrogen atoms on different L2− ligands, two interesting infinitely extended right helix chains are formed along the c-axis, and the two helix chains are combined to form a 3D framework structure of 1. In compound 2, the adjacent Mn2+ is bridged with four carboxyl oxygen groups in the ligand to form a binuclear structure unit {Mn2O4}. Each {Mn2O4} is linked to six organic ligands, and each ligand is linked to three {Mn2O4}, which together form a (3,6) linked 3D coordination polymer material. It is noteworthy that the interconnections between the layers form a lantern-like structure when viewed from the b-axis direction. Additionally, compounds 1 and 2 demonstrated temperature-dependent magnetic susceptibility (dc) and negative values of θ (equal to -10.59 K and -6.38 K), which are indicates the presence of weak antiferromagnetic interactions in both compounds 1 and 2.

In the context of the development of new agricultural sciences,innovatively integrating public basic courses with agricultural elements,and optimizing teaching methods,represent critical strategies for advancing the reform of agricultural science's characteristic basic courses.The course team has undertaken explorations and practices in integrating teaching content with agricultural characteristics,incorporating "agricultural flavor" into ideological and political education,and establishing a learning-centered,autonomous,cooperative,and inquiry-based teaching mode.Through these teaching reforms and practices,an effective integration of chemical knowledge with agricultural professional knowledge has been achieved,which is conducive to improving students'abilities to address issues within the agricultural field and providing support for the cultivation of exceptional talents in agriculture and forestry in the new era.

The present study reports the successful synthesis of three new magnetic coordination polymers, namely [Mn (BPTH)(H 2 O)] n (1), [Co(BPTH)(phen)] n (2), and [Co(BPTA)(phen)(H 2 O) 2 ] n (3), through a solvothermal method (H 2 BPTH = biphenyl-3,3 ' ,4,4 ' -tetracarboxyhydrazide, H 2 BPTA = biphenyl-3,3 ' ,4,4 ' -tetracarboxylic acid, phen = 1,10-phenanthroline). In compounds 1 and 2, the bishydrazide ligand H 2 BPTH is formed by in situ acylation of H 2 BPTA with hydrazine hydrate. All the three title compounds contain M 2 O 2 clusters ( M =Mn(1), Co(2) and Co (3)). In compound 1, the amido-oxygen atoms O1 coordinate with Mn 2 + to form a Mn 2 O 2 cluster, while the adjacent Mn 2 O 2 cluster is interconnected by the ligand's oxygen atoms O3 and O4, resulting in an infinite expansion into a 3D network structure. Compound 2 exhibits a 1D chain structure containing Co 2 O 2 clusters, which further extends into a 2D supramolecular layer through pi...pi stacking interactions. Compound 3 comprises adjacent Co 2 O 2 clusters interconnected by oxygen atoms O1, O2, and O5 on the ligand to form a 2D layered architecture. The 2D layers are linked through intermolecular O-H...O hydrogen bonds of H 2 BPTA ligands to form a 3D supramolecular network. Magnetic measurements reveal weak ferromagnetic behavior for compound 1 while compounds 2 and 3 exhibit weak antiferromagnetic interactions at different temperatures. Overall, this research presents new insights into the design and synthesis of coordination polymers with diverse structures and magnetic properties.

In this paper, lignocellulose components were separated under mild conditions to achieve hierarchical utilization of biomass. Cellulose was retained in cellulose pulp with highly crystalline structure, and lignin powder was recovered, which offered a possibility for the high-value utilization of lignocellulosic biomass. The extracted lignin (EL) was carbonized and activated to prepare lignin-based porous carbon microspheres (LPCMs) and further used as a substrate to interact with fluorescein-5-isothiocyanate (5-FITC) for the detection of biogenic amines (BAs). The fluorescence of 5-FITC was found to be quenched in the presence of LPCMs. And then, upon addition of BAs, 5-FITC was released from the surface of LPCMs, which resulted in the fluorescence recovery of 5-FITC. Thus, a novel “turn off–on” fluorescent probe was constructed for sensitive and visual detection of BAs. Meanwhile, the retained cellulose skeleton structure was used to prepare a smart identification label for real-time and visual evaluation of the freshness of pork and shrimp. This work realized the improvement of comprehensive utilization rate of lignocellulose and developed a rapid, efficient, and sustainable method which combined natural lignocellulose materials with green analytical technology for visually evaluating food quality.

Luminescent copper(I) iodide (CuI)-based coordination polymers (CPs) are well-known for their structural di-versity and strong photoluminescence and are considered as promising candidates for optical applications. Here, a fluorescent Cu2I2(2-ap)2 (1) (2-ap = 2-aminopyridine) CP was designed, synthesized, and applied to the effective detection of biothiols and antimicrobial study. Based on the strong thiaphilicity of copper (I), the CP 1 was used as a fluorescent probe to detect biothiols, which play important roles in regulating normal physiological processes due to their vital biological functions. Results revealed that the probe was able to achieve selective and sensitive detection of cysteine (Cys), glutathione (GSH), and homocysteine (Hcy) with low detection limits of 1.013 mu M, 1.051 mu M, and 1.034 mu M, respectively. Moreover, the probe was successfully applied to the detection of thiols in human urine, fetal bovine serum, and bovine serum albumin, which demonstrated the potential application in biological samples. Furthermore, a CP/cellulose nanofibers (CP/CNFs) composite film was fabricated for visual detection of biothiols and antimicrobial study. The developed composite film showed good antimicrobial activity against tested bacteria in vitro conditions, thus opening up the antimicrobial application of CP-doped composite film and providing a new perspective and prospect for potential application in food packaging.

We have established H 3 PW 12 O 40 · x H 2 O catalyzed O -alkylation of oximes with alcohols in DMC, and investigated the corresponding mechanism.

随着教学改革的不断深入,无机化学实验教学的改革也在积极探索.为提高无机化学实验课程的教学效果,弥补传统无机化学实验课程内容和考核方式的不足,设计一个综合性实验:碘酸铜的制备及其溶度积常数的测定作为考核内容.结果表明,以综合性实验作为考核内容,考核过程分步骤并细化考核评价指标,可以全面地考察学生实验操作技能和对知识的掌握,客观地反映学生的实验综合水平,对提高教学质量、培养专业人才具有重要意义.

Fluorescent cuprous iodide (CuI)-based coordination polymers (CuI-CPs) were widely used in the sensor field for high selectivity and sensitivity. Here, a new CuI-CP fluorescent probe was fabricated for the detection of spermine, spermidine and cysteine with dual-mode, which was capable of both convenient colorimetric analysis and ratiometric fluorescent detection. The fluorescence of CuI-CP solution was quenched and the solution changed from white to purple upon addition of spermine or spermidine, while the solution changed from white to yellow for cysteine. This probe exhibited selective, sensitive, rapid and linear response to spermine, spermidine and cysteine with a limit of detection of 0.57, 1.06 and 1.18 & mu;M, respectively. Furthermore, cellulose acetate was used as the matrix to fabricate intelligent fluorescent film for real-time and visual monitoring the freshness of pork samples based on distinct fluorescence changes under UV light. This work realized a rapid, efficient, and profitable method for visually evaluating food quality.

Nitrophenols are identified as the priority organic pollutants due to the chemical stability, water solubility, persistence, and toxicity to human health and the environment. Hence, removal of nitrophenols from waste water is vitally essential. In this study, amino-rich coordination polymer Cu2I2(MA)2 (MA = melamine) has been applied for efficient adsorption and catalytic reduction of nitrophenols, like 4-nitrophenol (4-NP), 2, 4-dinitro-phenol (DNP) and 2, 4, 6-trinitrophenol (TNP). The effect of various parameters like contact time, initial con-centrations, pH, and temperature on adsorption were investigated. The adsorption of nitrophenols fitted the pseudo-second-order kinetic model and Langmuir isotherms model well. The maximum adsorption capacities were 285.71, 232.02, and 131.57 mg g-1 for 4-NP, DNP, and TNP when initial concentrations were 50 mg L-1 at 293.15 K, respectively. The adsorption of nitrophenols is a spontaneous, endothermic, and entropy-driven process. The reduction reaction followed the pseudo-first-order kinetics, and the kinetic rate constants were 0.4413, 0.3167, and 0.17538 min- 1 for 4-NP, DNP, and TNP, respectively. The effect of initial nitrophenols concentration, anions, and temperature on reduction process was investigated. The mechanism of adsorption and catalytic reduction of Cu2I2(MA)2 was studied. The results demonstrated that Cu2I2(MA)2 exhibits excellent adsorption and catalytic activity to remove nitrophenols.

Herein, a facile, environmental-friendly, and sustain-able strategy for efficient separation, conversion, and utilization of lignocellulose components was developed. Lignocellulose compo-nents were separated by green deep eutectic solvent (DES). The extracted lignin had potential for downstream production of aromatic chemicals and was used to synthesize lignin-doped carbon dots (CDs) in a ratiometric fluorescent probe for detecting biogenic amines (BAs) that were generated from food spoilage. The preparation of CDs provided an efficient strategy to convert biomass waste into carbon-based nanomaterials. This probe exhibited a sensitive, rapid, and linear response to BAs with a low detection limit of 0.045 mu M. The retained cellulose with the crystal I structure was used to prepare cellulose nanofibers (CNFs) via oxidation and mechanical treatment. Furthermore, the CNFs were used as a matrix to fabricate CDs/CNFs films for real-time and visual food freshness monitoring. From biomass waste to rational applications, this study not only expanded the comprehensive utilization of lignocellulose in a green and environment-friendly manner but also demonstrated the prospects of CDs-based composite films in on-site monitoring of food quality and safety.

无机化学实验是化学实验的重要分支,是化学化工类学生进入大学后的第一门实验课程,也是学习其它化学实验的重要基础.针对大一新生的特点将基于以问题为导向的"PBL"教学模式并融合慕课手段引入到无机化学实验的教学过程中,改变传统实验教学的固化模式,提高学生学习的主动性及分析问题、解决问题的能力,为无机化学实验教学改革提供新的思路.

In this report, a novel metal-organic framework [Zn(BMTH)](n) (1) (H2BMTH = 5,6-benzimidazole diacylhydrazide) based on the coordination of acylhydrazide ligand and Zn2+ was synthesized, in which the H2BMTH ligand was generated via in situ acylation reaction between benzimidazole-5,6-dicarboxylic acid and N2H4. X-ray single-crystal diffraction analyses indicate that compound 1 displays a three-dimensional (3-D) network with the point (Schlafli) symbol of (4(2).6(3).8), where a parallelogram channel with the size of 11.63 x 10.59 angstrom(2) is observed. Furthermore, 1 is a promising luminescent sensor for detecting Cr2O72- and Fe3+. Note that Fe3+ solution was incorporated into compound 1 to construct the new sensor, Fe3+@1. As expected, Fe3+@1 can sense L-Cysteine (L-Cys) selectively, which can be designed as a novel "turn-on" fluorescence sensor of L-Cys. The study of fluorescence performance indicates that in the range of 0-25 mu M for L-Cys, the variation of the proposed approach exhibits a good linear relationship with corresponding detection limits of 0.892 mu M.