Heavy metal contamination is persistent due to non-biodegradability and toxicity. Here, a hierarchical MXene/NiCo2O4/PANI-modified carbon felt anode was developed to enhance extracellular electron transfer (EET) and thereby improve cathodic Cu2+ removal in microbial fuel cells (MFCs). The engineered anode reduced interfacial charge-transfer resistance, promoted electroactive biofilm formation, and reshaped the microbial community toward exoelectrogenic taxa (e.g., Geobacteraceae), leading to a markedly improved power output (Pmax = 2.47 ± 0.08 W m-2). In the cathode chamber, rapid Cu2+ remediation was achieved (99.2 ± 0.1% within 15 h at 30 mg L-1), following a dual-pathway process involving initial interfacial capture and subsequent electroreduction to insoluble Cu0/Cu2O. Moreover, stable Cu2+ removal under intermittent operation was enabled by the pseudocapacitive charge-buffering behavior of the NiCo2O4/PANI framework. This work clarifies how anodic interfacial engineering governs cathodic metal reduction and provides a scalable strategy for coupling metal remediation with energy recovery.

Northeast China boasts abundant resources of cold mountain grapes. This study focused on three varieties of cold mountain grape brandy, Beibing Hong (BBH), Shuanghong (SH), and Zuoshanyi (ZSY), with varying ageing periods to investigate changes in their physicochemical properties, nutrients, and aroma compounds. Results showed that alcohol content and pH gradually decreased with ageing, while total acidity (including inorganic acids) increased. Specific organic acids declined over time, whereas polyphenolic compounds increased with longer ageing. Furthermore, the total quantity of aroma substances in all three brandies was positively correlated with ageing duration, with 18-month-aged BBH brandy exhibiting the highest content and the richest aromatic variety. Clustering analysis via heat maps revealed that brandies aged 12 and 18 months grouped together, showing that ageing time correlated positively with most esters and alcohols and negatively with acids. No significant variations were observed in the contents of terpenes, aldehydes and ketones among the three brandy varieties.

In this paper, composite nanostructures are constructed successfully by combining conductive carbon-based materials with MoS2. The MoS2/reduced Graphene Oxide (rGO) composite was synthesized by hydrothermal method, and its morphology, elemental composition and microstructure were characterized in detail. Then, the MoS2/rGO composite material was modified on the glass carbon electrode (GCE) to construct the methyl parathion (MP) electrochemical sensor. The experimental results show that compared with a single MoS2/GCE modified electrode, the MoS2/rGO modified electrode exhibits significantly improved electrochemical performance. This boost can be attributed to the rGO’s high electrical conductivity and its good interface combination with MoS2, which work together to facilitate electron transport and enhance catalytic activity. In the electrochemical detection of MP, the MoS2/rGO modified electrode shows excellent sensitivity, and its detection limit of MP reaches 11.92 ng/mL, providing an effective solution for the detection of MP with high sensitivity.

With the advancement of China’s agricultural modernization and scientific and technological progress, there has been a substantial increase in corn production, resulting in significant agricultural waste of materials such as corncobs. Conventional incineration methods fail to efficiently utilize the recyclable resources present in corncobs. In this investigation, corncob biochar film (CBC) was synthesized through the pyrolysis of corncob. Single-factor and orthogonal experiments were used to determine the conditions needed to prepare biochar film with the best Cr(VI) adsorption effect. The experiments showed that at a heating rate of 5 °C/min, pyrolysis temperature of 500 °C and pyrolysis time of 120 min, the Cr(VI) removal rate of prepared biochar film reached 73.55% and the adsorption capacity was 18.39 mg/g. Meanwhile, the factors affecting the removal of Cr(VI), including pH value, initial concentration of Cr(VI) solution, dosage of adsorbent, adsorption kinetics and isothermal adsorption, were analyzed in detail. The structures of CBC before and after Cr(VI) adsorption were analyzed by SEM, FTIR, XRD, XPS, and BET. These findings demonstrate the efficacy of corncob biochar film in Cr(VI) removal.

Cadmium ion (Cd2+), as a typical heavy metal contaminant threatening food safety, poses potential risks to human health due to its residues in rice. Therefore, developing a rapid-response detection method to monitor and analyze Cd2+ in food is of great significance. This study constructs an electrochemical sensor based on NiO@Ag nanocomposite modified carbon paste electrode (NiO@Ag/CPE) for highly sensitive detection of cadmium ions (Cd2+) in rice. The NiO@Ag core-shell structure is synthesized by hydrothermal method, and its three-dimensional flower-like morphology and heterojunction interface effect synergistically enhance electron transport efficiency and adsorption sites. Optimization of detection conditions shows that in 0.1 M Acetic Buffer Solution (ABS, pH 5) with a deposition potential of -1.2 V and deposition time of 175 s, the sensor demonstrates a detection range for Cd2+ spanning from 0.01 to 200 mu M, within which two distinct linear intervals are observed: 0.01-10 mu M and 10-200 mu M. The detection limit is as low as 0.00317 mu M (calculated using the formula LOD = 3 sigma/k, where sigma is the standard deviation of the reagent blank and k denotes the slope of the linear regression equation), exhibiting a more than 10-fold increase in sensitivity compared to traditional carbon paste electrodes. The electrode also shows excellent selectivity (10-fold interfering ions cause signal variation <2.1 %) and stability (response retention rate of 91.8 % after 31 days). In actual rice sample detection, the standard addition recovery rate is 90.5 %-108.5 %, confirming the application potential and value of this sensor in food contaminant monitoring.

A novel electrochemical sensor (NiO/MoS₂/rGO/GCE) designed for the sensitive detection of methyl parathion (MP) pesticide residues has been developed. The NiO/MoS₂/rGO composite was synthesized via hydrothermal and solvothermal methods, with successful formation and optimized microstructural characteristics validated through scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Empirical results demonstrated that the incorporation of NiO markedly augmented both the electrochemically active sites and electron-transfer efficiency, thereby enabling the sensor to achieve an excellent linear detection range of 0.01–10 μg/mL for MP, accompanied by a notably low detection limit of 1.1 ng/mL (S/N = 3). Furthermore, the sensor exhibited superior anti-interference performance, achieving recovery percentages ranging from 97.7 to 108.8

Ag/ZnO composite materials were prepared using a hydrothermal method based on the optimal experimental conditions for synthesizing ZnO materials. These composites were utilized in the photodegradation of simulated wastewater containing 50 mg/L ammonium nitrogen. The optimal composite ratio was determined through experimentation, and Ag/ZnO composites were characterized using scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The results indicated that the Ag/ZnO composites exhibit microstructural features similar to ZnO materials, characterized by flower-like morphologies composed of clustered porous sheets with high crystallinity. Compared to pure ZnO, the Ag/ZnO-5

Adding heavy metals such as copper and zinc to animal feeds is common practice to promote growth, but meanwhile has side consequence of enhancing spread of antibiotic resistance genes (ARGs) in soil. This presents a global challenge to food security and human health. We in this study investigated the transmission of typical ARGs, i. e. β-lactamase genes (β-RGs), in dairy farm environments where dietary Cu and Zn were present in a wide range of concentration. The β-RGs were demonstrated to be highly prevalent across environmental media, with a relative abundance of 94.55%, dominated by mechanisms of antibiotic deactivation (93.75%) and cellular protection (6.25%). More importantly, we first found the transmission of ARGs to be highly dependent on the overlooked volcanic effect, i. e. low-concentration Cu (12-22 mg/kg) and Zn (45-80 mg/kg) acted as micronutrients necessary for microbial growth but facilitated ARGs transfer, whereas higher-concentration Cu (22-39 mg/kg) and Zn (80-153 mg/kg) became toxic to microbial communities and gene expression patterns. Notably, the specific microbial phyla Proteobacteria (2.28-82.94%), Bacteroidetes (0.02-56.48%) and Actinobacteria (1.62-12.92%) exhibited resistance at low concentration of Cu and Zn, which enhanced the transmission of β-RGs. However, this process was inhibited at higher concentration due to inactivation of microbes by Cu and Zn. The increase in resistance was first observed in class Gammaproteobacteria (2.02-88.51%) and Alphaproteobacteria (0.68-10.1%) with increased Cu and Zn concentration. This resulted in heightened transfer of ARGs by tnpA-07 (80.35%) due to protection of thicker cell membrane by chelation with Cu and Zn. This study not only offers mechanistic insights into the volcanic effect of dietary metals on dissemination of ARGs, but also has important implications for safe management of agricultural settings.

Photocatalysis leverages light energy for chemical transformations, presenting an environmentally friendly approach to mitigating pollution. We have developed Bi2WO6/Ag/ZnO composite nanomaterials that demonstrate enhanced photocatalytic efficiency. These nanomaterials have been characterized through advanced techniques such as x-ray diffraction and x-ray photoelectron spectroscopy. A key challenge in photocatalysis is the effective separation of electron-hole pairs, and our Bi2WO6/Ag/ZnO composites achieve an impressive degradation rate of 96.93% for methyl orange. This result notably exceeds previous performance standards and highlights the crucial role of Ag in broadening the light response spectrum of zinc oxide (ZnO), and the addition of Bi2WO6 in amplifying the electron-hole pair separation efficiency within these composite nanomaterials. These findings underscore the significant potential of Bi2WO6/Ag/ZnO composites in environmental detoxification and establish a new benchmark in photocatalytic material performance. The advancement of such nanomaterials could be transformative for environmental remediation strategies, offering efficient, sustainable, and cost-effective solutions to ecological challenges. This study underscores the pivotal role of materials science in advancing environmental sustainability.

Biochar, a carbon-dense material known for its substantial specific surface area, remarkable porosity, diversity of functional groups, and cost-effective production, has garnered widespread acclaim as a premier adsorbent for the elimination of heavy metal ions and organic contaminants. Nevertheless, the application of powdered biochar is hindered by the challenges associated with its separation from aqueous solutions, and without appropriate management, it risks becoming hazardous waste. To facilitate its use as an immobilization medium, biochar necessitates modification. In this investigation, sodium alginate, celebrated for its superior gelation capabilities, was amalgamated with polyvinyl alcohol to bolster mechanical robustness, thereby embedding biochar to formulate sodium alginate biochar microspheres (PVA/SA-FMB). A meticulously designed response surface methodology experiment was employed to ascertain the optimal synthesis conditions for PVA/SA-FMB. Characterization outcomes unveiled a highly developed surface abundant in functional groups and confirmed the successful incorporation of iron ions. Adsorption trials revealed that at a temperature of 25 °C and a pH of 2, the adsorption capacity of PVA/SA-FMB for Cr(VI) was 13.7 mg/g within the initial 30 min, reaching an equilibrium capacity of 26.03 mg/g after 1440 min. Notably, the material sustained a Cr(VI) removal efficiency exceeding 90% across five cycles, underscoring its rapid and effective Cr(VI) eradication performance. Kinetic and isothermal adsorption analyses suggested that the adsorption of Cr(VI) adheres to a pseudo-second-order kinetic model and the Freundlich isotherm, indicative of monolayer adsorption dominated by reaction mechanisms. X-ray photoelectron spectroscopy (XPS) analysis inferred that the adsorption mechanism predominantly encompasses electrostatic attraction, redox processes, and complex formation.

Corn is an important food crop, but its production often generates a large amount of corn cobs as waste. However, corn cobs contain rich polysaccharides, among which xylan is particularly noteworthy due to its various biological activities and wide potential applications. To improve the utilization rate of corn cobs, xylan is extracted from corn cobs using water extraction, examining the effects of three factors: extraction temperature, extraction time, and liquid-to-solid ratio on the extraction yield of xylan. Through response surface methodology, the optimal extraction conditions are obtained. The structure of the extract is analyzed using SEM, FTIR, and UV-VIS characterization techniques.

Au-RGO/TiO2 nanotubes were prepared by anodic oxidation and electrochemical deposition, and their performance in the photocatalytic degradation of ciprofloxacin was investigated. The results showed that, compared with TiO2 nanotubes and RGO/TiO2 nanotubes, the Au-RGO/TiO2 nanotubes had the highest ciprofloxacin degradation rate, reaching 96.93% in 180 min of photocatalysis. In addition, the possible degradation products of ciprofloxacin were analyzed by liquid chromatography-mass spectrometry, and the mechanism of degradation of ciprofloxacin by Au-RGO/TiO2 nanotubes was analyzed.

Potato starch wastewater, a byproduct of potato processing, is an escalating environmental concern due to its high concentrations of COD (chemical oxygen demand), ammonia nitrogen, and total phosphorus (TP). Addressing this challenge, this research introduced a novel method combining chitosan-modified biochar film (CBC) adsorption with subsequent ultrafiltration. SEM (scanning electron microscope), FTIR (Fourier transform infrared spectral), XRD (X-ray diffractometer), and BET (specific surface area) analyses validated CBC's enhanced surface characteristics, confirming successful chitosan (CS) film impregnation. CBC exhibited superior adsorption capacities, especially 40%wt-CBC, optimizing COD removal at 79.8%, ammonia nitrogen at 93.3%, and TP at 91.2%. Kinetic studies associated the adsorption process with a pseudo-second-order model, highlighting chemical adsorption. Additionally, the Langmuir isotherm model suggested monolayer adsorption with no inter-adsorbate interactions. The treated effluent, post adsorption, was directed through an ultrafiltration membrane, ensuring water quality suitable for reuse. This integrative treatment not only offers an effective solution for potato starch wastewater management but also underscores the potential for sustainable water resource recovery in the food processing sector.

综述了生物炭吸附处理氨氮废水的研究现状,介绍了物理改性、酸碱改性、金属离子改性和生物改性生物炭,光催化与生物炭联合技术,生物炭固定化微生物技术,生物炭三维电极技术在氨氮废水处理领域的应用进展,详细地介绍了各种方法对氨氮废水的处理效果及其优缺点.展望了生物炭吸附法在氨氮废水处理领域未来的研究重点和发展趋势.

In this study, an innovative Ag/ZnO/BC nanofilms composite material was synthesized by loading zinc oxide and silver on biochar nanofilms using a combination of hydrothermal and calcination methods using zinc oxide, silver and biochar as raw materials. Subsequent characterization analysis confirmed the successful synthesis of Ag/ZnO/BC nanofilms photocatalysts, and the Ag/ZnO nanocomposite particles were effectively loaded on the biochar nanofilms (BC). The composite exhibited robust photocatalytic removal under visible light irradiation under simulated wastewater conditions with an ammonia nitrogen concentration of 50 mg/L. The photocatalytic removal of ammonia and nitrogen pollutants in the composite was achieved by the use of Ag/ZnO nanoparticles. Specifically, the degradation of ammonia nitrogen pollutant reached a peak efficiency of 83.28%. Notably, the photocatalyst maintained over 80% degradation efficiency after four cycles, highlighting its sustained photocatalytic activity and stability. In conclusion, this study elucidated a feasible method to fabricate metal oxide–biochar thin-film composites with excellent adsorption and photocatalytic properties, thus providing a promising pathway for the remediation of organic wastewater, especially wastewater containing ammonia and nitrogen pollutants.

In recent years, wastewater containing heavy metal chromium has been discharged into water bodies. Metal chromium not only destroys the water environment but also poses a threat to human life and health. In order to solve the problem of chromium pollution more effectively, this study used corn straw as raw material to prepare biochar (MB) and used three methods: acid (HCl), alkali (NaOH) and metal salt (FeCl3) to modify biochar (HMB, NaMB and FeMB) and investigated the strengthening effect of modified biochar on Cr(VI) adsorption. The morphology and surface chemical composition of biochar were studied by XRD, SEM, XPS, FITR and other characterization methods. It was found that the modification of HCl, NaOH and FeCl3 improved the physical and chemical properties of MB (such as crystal structure, specific surface area, pore size and surface composite film), thus promoting the adsorption of Cr(VI). At the same time, an adsorption single-factor experiment, adsorption kinetics experiment, isothermal adsorption experiment and cyclic regeneration experiment were carried out on the four adsorbents. The effects of biochar on Cr(VI) adsorption performance under different pH, Cr(VI) initial concentration, biochar dosage and time were compared, and the adsorption mechanism of four adsorbents on Cr(VI) in aqueous solution was studied. It was found that the FeCl3-modified biochar provided more adsorption sites for chromium ions due to the successful loading of Fe, Fe3+ and iron oxide particles onto the MB surface to form a composite film, and the Fe-O groups introduced by the composite film formed a coordinated adsorption with dichromate ions. At 25 °C and pH = 2, FeMB reached saturation at 1440 min, the maximum adsorption capacity was 23.4 mg/g and its removal rate of Cr(VI) remained above 45% after five cycles. The adsorption of Cr(VI) was significantly enhanced.

以玉米秸秆为原料制备纳米纤维素/丙烯酸水凝胶并用于染料废水吸附.首先,采用表面接枝共聚法制备水凝胶,利用傅里叶变换红外光谱(FT-IR)、扫描电镜(SEM)、X射线衍射(XRD)和热重分析(TG)对其进行了表征,并进行水凝胶溶胀性能测试.结果表明:水凝胶具有立体蜂窝网状结构,丙烯酸的接枝共聚作用使样品结晶度降低、热稳定性增强.升高温度、碱性介质中水凝胶表现出更好的溶胀能力,但是介质中阳离子价态高溶胀能力下降.最后,对水凝胶吸附亚甲基蓝机理进行了探讨,吸附过程符合Langmuir等温吸附模型,以发生在水凝胶活性基团的单层吸附为主;吸附动力学符合准二级动力学模型,是一种化学吸附.

The purpose of this work is to study the crystal structural, element composition, valence state and optical properties of the MIT-Ag/ZnO/Bi2WO6 in order to be used for antibiotic degradation application. MIT-Ag/ZnO/Bi2WO6 materials were prepared by sol-gel and ultrasonic composite method using cefuroxime sodium as the template molecule. The obtained catalyst was characterized by different techniques. The crystal structure was analyzed by XRD and FTIR. The elemental and valence composition were analyzed by XPS. It was found that the imprinting process did not changed the crystal structure, elemental composition and valence state of Ag/ZnO/ Bi2WO6. The morphology was visualized by SEM. A heterojunction is formed between ZnO and Bi2WO6 as investigated by TEM analysis. The optical proprieties have been evaluated by DRS, a bandgap of 3.08 eV was found. PL results showed that the imprinting process inhibits the recombination of electron-hole pairs. Photocatalytic experiments were further carried out. MIT-Ag/ZnO/Bi2WO6 was selective to template cefuroxime sodium, and the degradation efficiency of cefuroxime sodium reached almost 100% under the irradiation of 250 W mercury lamp for 150 min. center dot OH and h(+) were the main active substances in the photocatalytic process.

简述了不同预处理方法包括化学法、物理法和生物法在分离生物质各组分当中的应用,叙述了各预处理方法的优缺点,回顾了近年来基于传统的预处理技术在高效与环境友好等方面进行的工艺优化,从分离效率、预处理条件以及分离后各组分理化性质的变化分析不同的预处理工艺,高污染、利用率差仍是限制生物质综合利用发展的主要因素,并对未来生物质处理技术的发展方向进行了展望,指出了生物质的预处理技术应在高效率、环境友好以及循环利用的可控性方面进行新技术的研发,联合处理仍是今后生物质预处理技术的一个重要发展方向.