The development of high-capacity and easily separable adsorbents is crucial for efficient dye wastewater treatment. Herein, a magnetic Fe3O4@ZIF-67 nanocomposite was synthesized via a facile in situ method to enhance its separation and recovery capabilities. The characterization results confirmed the successful synthesis of this nanocomposite. The batch adsorption experiments demonstrated that its adsorption capacity reached as high as 949.5 mg·g−1. This process can be well described by the Langmuir and pseudo-second-order models, indicating it is a single-layer chemical adsorption. The thermodynamic studies revealed the adsorption to be spontaneous and endothermic. This work not only presents Fe3O4@ZIF-67 as a highly efficient and recyclable adsorbent for malachite green (MG) but also validates the strategy of constructing magnetic MOF-based composites for practical environmental remediation.

ABSTRACT A composite aerogel of zeolitic imidazolate framework‐67 (ZIF‐67) and agarose (AG), denoted as ZIF‐67@AG, was successfully prepared for efficient removal of malachite green (MG). Comprehensive characterization confirmed the successful formation of the composite: X‐ray diffraction (XRD) patterns retained the characteristic peaks of ZIF‐67, scanning electron microscopy (SEM) revealed uniform dispersion of ZIF‐67 within a porous AG network, Fourier transform infrared spectroscopy (FT‐IR) confirmed the characteristic functional groups of both components, and x‐ray photoelectron spectroscopy (XPS) verified the presence of constituent elements. Batch adsorption experiments were conducted to investigate the effects of contact time, adsorbent dosage, solution pH, coexisting ions, and temperature on MG removal. The adsorption equilibrium data were well fitted by the Langmuir isotherm model, with a calculated maximum adsorption capacity of 1112 mg·g −1 . Kinetic analysis revealed that the pseudo‐second‐order model provided the best fit, suggesting a chemisorption‐dominated process. Thermodynamic studies confirmed that the adsorption was spontaneous and endothermic. Furthermore, the ZIF‐67@AG composite showed good reusability, maintaining a removal efficiency above 79% after six adsorption–desorption cycles. These results demonstrate that ZIF‐67@AG is a promising adsorbent for the efficient removal of MG from wastewater.

Triazine-phosphonitrile porous polymers (TPPOPS-1 and TPPOPS-2) for the efficient recovery of Gd3+ from aqueous solutions were synthesized and evaluated in this study. The introduction of abundant rigid cyclic architectures significantly enhanced the polymer's pore stability. The resulting TPPOPS-2 exhibited a notably high specific surface area of 996.7 m2 center dot g-1 representing a twofold increase over that of TPPOPS-1(468.4 m2 center dot g-1). The combination of high porosity and abundant electron-rich functional groups (-P=N-, -C-NH-) endowed TPPOPS-2 with a maximum Gd3+ adsorption capacity of 313.8 mg center dot g-1, which was 105 % higher than that of TPPOPS-1. Characterization techniques including XPS and FTIR revealed the critical role of N/P functional groups in forming stable coordination bonds with Gd3+. Analysis of adsorption isotherms and kinetics demonstrated that the adsorption process conformed more closely to the Langmuir model and the pseudo-second order kinetic model than to the Freundlich model and pseudo-first order kinetic model. These findings indicate that monolayer adsorption and chemisorption predominantly govern Gd3+ uptake on the polymer surface. Furthermore, TPPOPS-2 exhibited high adsorption selectivity for Gd3+ in multi-ion systems and maintained 75 % of its adsorption capacity after five adsorption-desorption regeneration cycles. This work paves a novel pathway for developing advanced materials for high-performance heavy rare earth resource recovery.

The Zr-based metal organic framework UiO-66 was synthesized using the solvothermal method. The adsorption properties of UiO-66 for organic dye Congo red (CR) were studied. The results showed the excellent adsorption performance of UiO-66 toward CR. The adsorption equilibrium data were consistent with the Langmuir adsorption isotherm model. The adsorption kinetics, thermodynamics, and mechanism of CR on UiO-66 were studied. The results of cyclic adsorption experiments showed that UiO-66 could be used repeatedly to adsorb CR. The metal organic framework UiO-66 is good quality and has an excellent removal efficiency for the dye Congo red (CR). The adsorption of CR by UiO-66 is mainly a monolayer adsorption on the surface of UiO-66. The adsorption process is dominated by chemical adsorption. The UiO-66 could be used repeatedly to adsorb CR.

An environmentally friendly and low-cost chitosan-containing polysaccharide (CP) composite ZIF-8/CP was designed and prepared based on the difficulty of separating the traditional adsorbent from the water phase. ZIF-8/CP was synthesized through in-situ growth approach. The physical, chemical and structure properties of ZIF-8/CP were determined through a series of characterization methods, including SEM, FT-IR and PXRD. The effects of touch time, pH, temperature, and co-existing ions on adsorption were assessed. In addition, kinetics, isotherms of adsorption and thermodynamics were examined. The data of isotherms for adsorption indicated that the adsorption of ZIF-8/CP on MG was similar to the Langmuir model, with a maximum adsorption capacity of 1428.57 mg/g. Moreover, the kinetic parameters were consistent with the pseudo-2nd-order equation. Thermodynamic studies (Δ G < 0, Δ H > 0) demonstrated a heat-absorbing and spontaneous adsorption process. Our study reveals that ZIF-8/CP has good adsorption properties and environmental properties.

High flame retardancy, satisfactory mechanical properties are crucial for polymeric composites employed in fields with safety requirements. Inorganic fillers can effectively regulate the structure and composition of polymeric materials and have become an effective strategy for fabricating high-performance polymeric composites. Herein, aluminum phosphate–coated sepiolite (Sep@AlPO4) fillers are fabricated as a multifunctional additive to modify polyethylene oxide (PEO), PEO nanocomposites were prepared via incorporation of Sep@AlPO4 and phenethyl-bridged 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) derivative (DiDOPO) in the PEO matrix, and the synergistic effects between Sep and AlPO4 are discussed. The results reveal that Sep@AlPO4 could simultaneously enhance the flame retardancy and strengthen the mechanical properties of PEO/DiDOPO. Additionally, Sep@AlPO4 could increase the viscosity, storage modulus, and loss modulus of the composites. This study provides an effective strategy for fabricating enhanced flame retardants to improve the performance of polymers.

Graphene oxide@sodium alginate (GO@SA) composites were prepared by combining graphene oxide (GO) with sodium alginate (SA) for adsorption of Pb(II). Fourier-transform infrared spectra (FT-IR) and field emission scanning electron microscopy (FESEM) were used to characterize the structure and morphology of the composites. And the adsorption performance of Pb(II) by GO@SA was studied. The adsorption capacity of Pb(II) by GO@SA increased with the increase of pH and temperature. The adsorption process was consistent with the Langmuir isothermal adsorption model and quasi-second-order kinetic model, and the adsorption process was spontaneous and endothermic. At 303.15 K, the maximum adsorption capacity fitted by the Langmuir isothermal model was 241.5 mg/g.

The designability of the morphology and composition of inorganic particles plays a vital role in controlling the flame retardancy of polymers, an arena in which inorganic fillers have become a hot spot in the research field of halogen-free flame retardants. Here, aluminum phosphate (AlPO4)-coated silica (SiO2) (SiO2@AlPO4) particles were prepared via a facile one-pot heterogeneous precipitation strategy. The effect of the AlPO4 content on the morphology of SiO2@AlPO4 was systematically studied to regulate the dispersion of AlPO4 nanoparticles. Moreover, the effect of SiO2@AlPO4 on the flame retardancy of epoxy (EP) resin was further investigated. Results show that SiO2@AlPO4 simultaneously strengthens the mechanical properties and improves the flame retardancy of EP and that this phenomenon may be attributed to the synergistic effect of the AlPO4 nanoparticles and SiO2 microparticles. This work details a facile yet effective strategy to engineer the morphology and composition of inorganic particles to control the properties of polymers.

Multi-walled carbon nanotubes (MWCNTs) were treated by reflux oxidation in a mixture (HNO3 and H2SO4), hydroxyl (–OH) and carboxyl (–COOH) functional groups were introduced on the surface of MWCNTs to obtain the Oxidized-MWCNTs (OMWCNTs). OMWCNTs were used as adsorbent to removal of Pb(II) from wastewater. The effects of contact time, initial concentration of Pb(II), OMWCNTs dosage, pH and coexisting ions (K+, Na+, Ca2+, Mg2+) on the adsorption and removal of Pb(II) by OMWCNTs were systematically studied. The adsorption of Pb(II) by OMWCNTs could reach equilibrium in 10 min. The pH > 5 is conductive to the adsorption of Pb(II) by OMWCNTs. The coexisting ions (K+, Na+, Ca2+, Mg2+) had almost no effect on the adsorption of Pb(II) by OMWCNTs. The results showed that the isothermal data fit the Freundlich and Langmuir isotherm models. The maximum adsorption capacity was 558.66 mg/g for Pb(II) from Langmuir isotherm. The pseudo-second-order kinetic model could well describe the adsorption process of Pb(II).

Here, the thermodynamics and kinetics of Pb2+ adsorption and removal on Ni-MOF-74 from wastewater were studied. The effects of pH value, contact time, Pb2+ initial concentration, Na+ concentration, Ni-MOF-74 loading and adsorption temperature were systematically studied. The results showed a good Pb2+ adsorption capacity of the MOF. The adsorption of Pb2+ was analyzed by using different isotherms as well as different kinetics models. The results showed that Tempkin adsorption isotherm and pseudo-2nd-order kinetics were followed by the adsorption of Pb2+ on Ni-MOF-74. Thermodynamic studies (Delta G<0, Delta H<0) showed that the adsorption process is exothermic and spontaneous. The results revealed that Ni-MOF-74 has a real prospect for the application in the adsorption and removal of Pb2+.

Nowadays, the epidemic, employment, and academic pressures are seriously affecting our physical and mental health. Herein, we designed a magneto-controlled photoelectrochemical immunosensor for noninvasive monitoring of salivary cortisol regarded as a pressure biomarker. A competitive immunoassay model was established by coupling bovine serum albumin-cortisol modified magnetic beads (MB-BSA-cortisol) with silver nanoclusters (Ag NCs)-labelled anti-cortisol antibody, and quantity analysis was operated by photoelectrochemical measurement of the CdS/Au electrode as an ion-exchange platform. Accompanying the formation of immune complexes, the carried Ag NCs were readily dissolved with nitric acid to produce abundant silver ions, which transferred to the electrode for ion-exchange reaction with CdS quantum dots to produce Ag 2 S, a new electron–hole capture site, leading to a decrease in the photocurrent intensity. The photocurrent signal gradually recovered with the increase of concentration of target cortisol, acquiring the signal-on mode competitive immunosensing system, which is propitious to the detection of small molecules. Within optimal conditions, this sensor had a satisfactory linear relationship in the range of 0.0001–100 ng mL −1 with favorable repeatability, specificity, and acceptable method accuracy. The detection limit was as low as 0.06 pg mL −1 . In addition, this strategy provided new thought for the test of other small-molecule analytes and immunosensor applied in the complex biological system.

本文采用溶剂热法合成金属有机框架材料Ni-BDC,然后将粉末状的Ni-BDC与高分子材料琼脂糖进行复合,得到易于从水中分离的复合材料Ni-BDC/琼脂糖.研究复合材料Ni-BDC/琼脂糖对亚甲基蓝的吸附性能.系统的研究接触时间、亚甲基蓝初始浓度及温度等因素对Ni-BDC/琼脂糖吸附去除亚甲基蓝效果的影响.采用等温吸附模型、吸附动力学模型及吸附热力学对Ni-BDC/琼脂糖吸附亚甲基蓝的作用机理和行为进行探究和分析.Ni-BDC/琼脂糖对亚甲基蓝的吸附更符合Langmuir吸附等温模型和吸附二级动力学模型.Ni-BDC/琼脂糖对亚甲基蓝的吸附过程是吸热的、自发的.

将氧化多壁碳纳米管(OMWCNTs)和海藻酸钠(SA)进行复合,制备氧化多壁碳纳米管/海藻酸钠(OMWCNTs/SA)复合材料,系统研究了各因素对OMWCNTs/SA吸附Pb(Ⅱ)效果的影响.结果表明:OMWCNTs/SA对Pb(Ⅱ)的吸附量随溶液pH和温度的升高而增大,但随溶液中Na+浓度的增大而减小.在240min时,OMWCNTs/SA对Pb(Ⅱ)的吸附达到平衡.吸附过程符合Langmuir等温吸附模型和拟二级动力学模型,且自发吸热.在303.15K时,Langmuir等温吸附模型拟合得到的最大吸附量为402.029mg/g.

高校教学环境随着信息技术的快速发展而发生了巨大变化,传统的教学方式已经不能适应当前的环境和需求.在大数据背景下,教育信息化正在快速推进并推动了课程教学模式的改革.本文以《物理化学》课程为例,阐述了该课程在大数据时代进行课程教学改革的必要性以及利用网络教学资源、平台及大数据分析开展教学改革激发学生学习兴趣和提高教学质量的策略.同时,利用教师科研课题与《物理化学》课程内容之间的联系,激发学生的学习兴趣,引导学生积极主动学习.

气凝胶具有低密度、高比表面积、高孔隙率等特性,在水污染处理领域具有广阔的应用前景.以天然绿色高分子材料纤维素纳米晶(CNC)和壳聚糖(CS)为原料,通过冷冻干燥法和固相交联技术制备了具有良好水溶液稳定性的CNC/CS气凝胶.采用扫描电子显微镜(SEM)对气凝胶表观形貌进行了表征,采用分光光度法考察了气凝胶对水中六价铬离子(Cr(Ⅵ))的吸附性能,并对吸附结果进行了拟一级和拟二级动力学拟合.结果表明,CNC含量为50％时气凝胶的水稳定性最好,在去离子水中48 h震荡后的质量残留率达到93.8％.气凝胶具有丰富的蜂窝状孔结构,对Cr(Ⅵ)的吸附容量最高可达67.377 mg/g.气凝胶对Cr(Ⅵ)具有较快的吸附速率,当Cr(Ⅵ)溶液浓度低于60 mg/L时能够在24 h内达到吸附平衡.吸附动力学拟合结果表明CNC(50％)/CS气凝胶对Cr(Ⅵ)的吸附行为符合拟二级吸附动力学模型,说明吸附过程以化学吸附为主.

Polypropylene (PP), as a general thermoplastic polymer, is broadly used in different fields. However, the high flammability, melt dripping and poor mechanical properties of PP are a constraint to the expansion of its applications. In this paper, PP composites containing a combination of a phenethyl-bridged DOPO derivative (PN-DOPO) and organic montmorillonite (OMMT) were prepared via melt blending. The synergistic effects of PN-DOPO and OMMT on the flame retardancy, thermal stability and mechanical properties of PP composites were investigated systematically. The results showed that 20 wt% addition of PN-DOPO with OMMT improved the flame retardancy of PP composites. In particular, the introduction of 17 wt% PN-DOPO and 3 wt% OMMT increased the LOI values of the PP matrix from 17.2% to 23.6%, and the sample reached the V-0 level and reduced the heat release rate and total heat release. TGA indicated that OMMT could improve the thermal stability of the PP/PN-DOPO blends and promote the char residues of PP systems. Rheological behaviour showed a higher storage modulus, loss modulus and complex viscosity of PP/PN-DOPO/OMMT composites, suggesting a more effective network structure. In addition, the tensile strength, flexural properties and impact strength of the PP/PN-DOPO/OMMT composites actually increased for a good dispersion effect. Combined with the char layer analysis, the introduction of OMMT promoted more continuous and compact structural layers containing an aluminium–silicon barrier and phosphorus-containing carbonaceous char in the condensed phase. OMMT can improve the flame retardancy, thermal stability and mechanical properties of PP, and, thus, PN-DOPO/OMMT blends can serve as an efficient synergistic system for flame-retarded PP composites.

Polymer blending has been widely used to fabricate polymeric films in the last decade due to its superior properties to a single component. In this study, an aluminum phosphate-coated halloysite nanotube (HNTs@AlPO4) was fabricated using a one-pot heterogeneous precipitation method, organically modified HNTs@AlPO4 (o-HNTs@AlPO4) was used to improve the performance of polyethylene oxide/poly(butylene adipate-co-terephthalate) (PEO/PBAT) blends, and the mechanical and rheological properties of the PEO/PBAT/o-HNTs@AlPO4 films were systematically discussed. According to our results, there is an optimal addition for adequate AlPO4 nanoparticle dispersion and coating on the surface of HNTs, and organic modification could improve the interfacial compatibility of HNTs@AlPO4 and the polymeric matrix. Moreover, o-HNTs@AlPO4 may serve as a compatibilizer between PEO and PBAT, and PEO/PBAT/o-HNTs@AlPO4 films have better mechanical and rheological properties than the PEO/PBAT blends without the o-HNTs@AlPO4 component.

The composite zeolitic imidazolate frameworks@agarose (ZIF-8@AG) was prepared by ZIF-8 and agarose (AG) in this study. The composite ZIF-8@AG with a good quality, was assessed for Pb(II) adsorption and regeneration from water. The effects of the contact time, initial concentration of Pb(II), adsorbent dosage, pH, coexisting ions (Ca2+ and Mg2+), temperature and other factors on the adsorption performance of Pb(II) on ZIF-8@AG were investigated. The pseudo-second-order kinetic model can well describe the adsorption process of Pb(II) on ZIF-8@AG. Thermodynamic parameters (Delta G, Delta H and Delta S) confirmed exothermic and spontaneous process. In the regeneration experiment, ZIF-8@AG maintained a high adsorption capacity for Pb(II) after 6 times of adsorption-desorption cycles. The experimental results showed that the ZIF-8@AG not only has a high adsorption efficiency for Pb(II), but also has a good stability for recycling.