CARBOHYDRATE POLYMERS
·
2015
·
IF 4.074
Guangyang Liu,Tengfei Li,Xin Yang,Yongxin She,Miao Wang,Jing Wang,Min Zhang,Shanshan Wang,Fen Jin,Maojun Jin,Hua Shao,Zejun Jiang,Hailong Yu
A novel fluorescence sensing strategy for determination of atrazine in tap water involving direct competition between atrazine and 5-(4,6-dichlorotriazinyl) aminofluorescein (5-DTAF), and which exploits magnetic molecularly imprinted polymer (MMIP), has been developed. The MMIP, based on Fe 3 O 4 -chitosan nanoparticles, was synthesized to recognize specific binding sites of atrazine. The recognition capability and selectivity of the MMIP for atrazine and other triazine herbicides was investigated. Under optimal conditions, the competitive reaction between 5-DTAF and atrazine was performed to permit quantitation. Fluorescence intensity changes at 515 nm was linearly related to the logarithm of the atrazine concentration for the range 2.32–185.4 μM. The detection limit for atrazine was 0.86 μM (S/N = 3) and recoveries were 77.6–115% in spiked tap water samples.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2020
·
IF 5.065
Mina Keshvardoostchokami,Mahyar Majidi,Abbasali Zamani,Bo Liu
Fe 3 O 4 /chitosan/ZIF-8 nanocomposite as a novel bio-adsorbent for phenol removal is reported in the current work. The nanocomposite was prepared in situ, and ZIF-8 particles with rhombic dodecahedron morphology were grown on the composite successfully. FTIR, XRD, FESEM, TEM, BET, and VSM were applied to analyze the nanocomposite physiochemically. Central composite design model (CCD) was applied to optimize effective factors such as phenol initial concentration, pH, time, and adsorbent dosage on phenol uptake. The optimum condition was 77.21% (6.43 mg/g) uptake of phenol from 20 mL solution with initial phenol concentration of 20.22 mg/L and pH = 9.91, by 0.1 g of the adsorbent after 43.44 min. The pseudo-second-order and Langmuir patterns as kinetic and isotherm models interpreted phenol adsorption very well. The current research presents a deep understanding of the formation of Fe 3 O 4 /chitosan/ZIF-8 nanocomposite, which has a suitable potential in phenol adsorption.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2018
·
IF 4.61
Chunzhen Fan,Kan Li,Yi He,Yalin Wang,Xufang Qian,Jinping Jia
Although many magnetic chitosan materials have been prepared for adsorption of metal ions , there is no standard method for comprehensive evaluation of material performance. The common practice simply compares either adsorption capacity (Q) or saturation magnetization (M s ) of interested materials; however, these two important parameters often work in opposite way. This study aims to establish two methods for evaluation of the overall performance of magnetic materials. The proposed methods consider both heavy metal ion adsorption capacity and magnetic recovery of the material after use. The first method introduces adsorption recovery index (ARI, ARI = Q t ), which is calculated using Q and recovery time (t) needed for achieving 98% material recovery. Higher ARI value shows better performance of a magnetic material. The second method uses effort-vector data visualization, in which the position of a magnetic material is shown on a coordinate depicted using normalized Q and M s value. The distance of the data point to the target (ideal Q and M s value) indicates the performance of the material. The shorter the distance, the better the overall performance is. Two series of MCBs with different Fe 3 O 4 chitosan mass ratios were prepared by using embedding method and chemical co-precipitation method respectively. They were used as model compounds for investigation of the feasibility of the proposed evaluation methods through adsorption of various metal ions (Ag + , Cu 2+ , Hg 2+ , Cr 3+ and Cr 6+ ) and MCBs recovery test. The best performers were able to be identified by using both methods and the results agreed with each other. Compared with ARI, the effort-vector data visualization was more straightforward and easier to use. This method was successfully applied to evaluate a wide selection of magnetic materials, including those prepared in this work and reported from literatures, for their overall performance.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2017
·Vol. 19
·期 10
·1-12
·
IF 2.02
Tian Fei,Niu Libo,Chen Bo,Gao Xuejia,Lan Xingwang,Huo Li,Bai Guoyi
A novel magnetic core-shell nanocomposite Fe 3 O 4 @Chitosan@ZnO was successfully prepared by in situ chemical precipitation method. It has a clear core-shell structure with magnetic Fe 3 O 4 (about 160 nm in diameter) as core, chitosan as the inner shell, and ZnO as the outer shell, as demonstrated by the transmission electron microscopy and the related elemental mapping. Moreover, this nanocomposite has high magnetization (43.6 emu g −1 ) so that it can be easily separated from the reaction mixture within 4 s by an external magnetic field. The introduction of the natural chitosan shell, instead of the conventional SiO 2 shell, and its combination with the active ZnO ensures this novel nanocomposite green character and good catalytic performance in the synthesis of 2-benzimidazoles with moderate to excellent isolated yields at room temperature. Notably, it can be recycled seven times without appreciable loss of its initial catalytic activity, demonstrating its good stability and making it an attractive candidate for the green synthesis of 2-benzimidazoles.
A novel magnetic core-shell nanocomposite exhibited high activity and good stability in the green synthesis of 2-benzimidazoles under mild reaction conditions.
研究领域:
材料科学
·
纳米技术
·
催化
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Weisen Yang,Yifei Liu,Yaqin Zhu,Wenlong Jiang,Fengshuo Shi,Jiapeng Hu,Shaohua Jiang,Shaoju Jian
Aquatic ecosystem contaminated by organic dyes is one of the most crucial issues plaguing people worldwide, while water remediation through adsorption technology is the most sustainable option. Herein, two chitosan-based adsorbents were successfully fabricated by a facile one-step method under alkaline condition via electrospraying technology, then the above two materials were cross-linked with epichlorohydrin and grafted triethylenetetramine to prepare two kinds magnetic Fe 3 O 4 /CS-ET-1 and Fe 3 O 4 /CS-ET-2 microspheres for remediation of anion dyes namely Congo red (CR) in wastewater respectively. The morphology features, structure, composition, thermal stability, and pore diameter of the two adsorbents were acquired by SEM coupled with EDX, XRD, FTIR, TGA, and BET. The adsorption behavior of Fe 3 O 4 /CS-ET-1 and Fe 3 O 4 /CS-ET-2 microspheres towards CR from water was systematically evaluated. The determined isoelectric points (pHpzc) of Fe 3 O 4 /CS-ET-1 and Fe 3 O 4 /CS-ET-2 are orderly 7.4 and 7.8. The results confirmed that the CR remediation process can be simulated by PSO kinetic model ( R 2 > 0.995) along with Langmuir isotherm ( R 2 > 0.998) with maximal CR adsorption amounts by Fe 3 O 4 /CS-ET-1 and Fe 3 O 4 /CS-ET-2 microspheres of 1145.42 and 617.28 mg g −1 at pH = 7 and T = 25 °C, respectively. The negative Δ G 0 , positive Δ H 0 (28.65 and 8.02 kJ mol −1 ), and positive Δ S 0 (112.29 and 62.71 J mol −1 K −1 ) signified that the adsorption of CR onto Fe 3 O 4 /CS-ET-1 and Fe 3 O 4 /CS-ET-2 microspheres surface was spontaneous and endothermic in nature. After four consecutive cycles, both magnetic microspheres remained a superior CR removal performance, indicative of the stability and recyclability of the adsorbents.
研究领域:
环境科学
·
材料科学
·
化学工程
·
水处理
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）