WATER RESEARCH
·
2024
·
IF 11.4
Hongmei Tang,Meiqing Chen,Pingxiao Wu,Yihao Li,Tianming Wang,Jiayan Wu,Leiye Sun,Zhongbo Shang
Schwertmannite (Sch) is considered as an effective remover of Chromium (Cr) due to its strong affinity for toxic Cr species. Since the instability of Sch, the environmental fate of Cr deserves attention during the transformation of Sch into a more stable crystalline phase. The ubiquitous manganese(II) (Mn(II)) probably affects the transformation of Sch and thus the environmental fate of Cr. Therefore, this study investigated the impact of Mn(II) on the transformation of Cr-absorbed Sch (Cr-Sch) and the associated behavior of SO 4 2− and Cr. We revealed that the transformation products of Cr-Sch at pH 3.0 and 7.0 were goethite and Sch, respectively. The presence of Mn(II) weakened the crystallinity of the transformation products, and the trend was positively correlated with the concentration of Mn(II). However, Mn(II) changed the transformation products of Cr-Sch from hematite to goethite at pH 10.0. Mn(II) replaced Fe(III) in the mineral structures or formed Mn-O complexes with surface hydroxyl groups (-OH), thereby affecting the transformation pathways of Sch. The presence of Mn(II) enhanced the immobilization of Cr on minerals at pH 3.0 and 7.0. Sch is likely to provide an channel for electron transfer between Mn(II) and Cr(VI), which promotes the reduction of Cr(VI). Meanwhile, Mn(Ⅱ) induced more -OH production on the surface of secondary minerals, which played an important role in increasing the Cr fixation. In addition, part of the Mn(Ⅱ) was oxidized to Mn(Ⅲ)/Mn(Ⅳ) at pH 3.0 and pH 7.0. This study helps to predict the role of Mn(II) in the transformations of Cr-Sch in environments and design remediation strategies for Cr contamination.
研究领域:
环境科学
·
矿物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Zhaohui Huang,Xiaoli Wang,Peng Du,Chuanqi Feng,Ping Niu,Dongmei Xu,Lumin Wang,Wei Gao,Aixin Song
Manganese(II) halides have received a booming development owing to their flexible structures and remarkable optical properties, whereas those with multimode luminescence color changes under specific stimuli are rarely reported. In this study, we synthesized a zero-dimensional (C5H14NO)2MnBr4 single crystal, which experiences an order–disorder phase transition from P21/c to P2/m at 268 K. Intriguingly, the emission color of (C5H14NO)2MnBr4 exhibits a “symmetric” switching of green–yellow–orange–red–orange–yellow–green within the temperature range of 80–420 K. For the low-temperature phase (LTP) below 268 K, the green and red lights at 510 and 640 nm are derived from the d–d electron transition of Mn(II) and the emission of self-trapped excitons (SETs), respectively. For the high-temperature phase (HTP) above 268 K, the dual emission peaks at 530 and 640 nm can be attributed to the simultaneous existence of trapping and detrapping processes of the STEs. Taking advantage of the unique thermochromic behaviors of (C5H14NO)2MnBr4, the temperature-responsive anticounterfeiting labels and encryption codes with multilevel design and high security have been constructed. This work provides new insights for the preparation of metal halides with multiple luminescence performances, facilitating the development of anticounterfeiting and information protection technologies.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2017
·Vol. 9
·期 17
·2553-2560
·
IF 1.9
Lei Meng,Yaqing Yuan,Guang Pu,Na Xu
Highly blue luminescent and water-soluble silicon nanoparticles (Si NPs) are prepared by an efficient one-pot hydrothermal route from (3-aminopropyl) trimethoxysilane and ascorbic acid at 160 °C. The label-free Si NPs are demonstrated as an effective fluorescent probe for selective recognition of Mn2+. The linear range is from 2.5 to 250 μM and the detection limit is calculated to be 1.1 μM due to Mn2+ induced Si NP aggregation (turn-off). Additionally, the quenched fluorescence can be restored in the presence of EDTA because the EDTA can grab Mn2+ from the aggregated Si NPs–Mn2+ system owing to its strong chelating ability (turn-on). This sensing system based on the “on–off–on” fluorescence switching method can facilitate further development in Mn2+ detection.
研究领域:
分析化学
·
纳米材料科学
·
环境监测
✓ 已验证
产品关联
DOI
高影响因子
ACS ES&T Water
·
2025
·
IF 4.3
Wen-Long Wang,Peng-Hui Liu,Jung-Hyun Son,Hang Su,Min-Yong Lee,Hong-Ying Hu,Qian-Yuan Wu,Uwe Hübner
The combination of ozonation and Mn(II) (O3/Mn(II)) is expected to synergistically eliminate recalcitrant organic micropollutants in water. However, the decay of O3, formation of •OH and reactive manganese species (RMnSs), and synergism in micropollutant degradation have not been comprehensively understood. Herein, the synergism of O3 and Mn(II) was observed to be pH-dependent. Compared to ozonation alone, O3/Mn(II) preferentially formed Mn(V and VI) and slightly increased •OH yield (from 0.22 to 0.30) at acidic pH 4–5, while it preferentially formed Mn(VII) and significantly increased OH yield (from 0.52 to 0.74) at circumneutral pH 6–7. Thereafter, O3/Mn(II) prominently increased RMnS exposure at acidic pH, while it dramatically diminished O3-exposurse to increase •OH exposure at circumneutral pH. As a result, O3/Mn(II) outperformed ozonation alone for the degradation of various O3-resistant micropollutants (3.7–7.9 times faster). For example, the RMnSs (82.7% contribution) and •OH (84.2% contribution) were the dominant contributors to the degradation of the isothiazolinone biocide (5-chloro-2-methyl-4-isothiazolin-3-one) at acidic and circumneutral pH, respectively. Mn(II) can enhance the removal of O3-resistant micropollutants in relatively clean waters (e.g., tap water), but its effectiveness was limited in more contaminated waters (e.g., WWTP effluent). These findings support the practice and pH optimization of the O3/Mn(II) in various water types.
研究领域:
环境科学
·
水处理工程
✓ 已验证
产品关联
DOI
高影响因子
Analytical Chemistry Letters
·
2011
·
IF 0
Ning Li,Haitao Zhang,Mengxing Liu,Yukun Wang,Jingjun Ma,Jingci Li,Xinxin Liu
Solid-phase extraction (SPE) clean-up combined with solidified floating organic drop microextraction (SFODME) has been developed as a new approach for the extraction and determination of trace manganese(II) in environmental water and vegetable samples. After purification of the samples by a graphene-packed SPE cartridge, SFODME technique was performed on the obtained solution. The main parameters affecting the performance of SFODME, such as type of extraction solvent as well as extraction volume, time, temperature, pH, the amount of the chelating agent, and salt effect were investigated and optimized. Under optimum conditions, a preconcentration factor of 81.0 was obtained from 7.0 mL of sample solution. The calibration graph was linear in the range from 1.90 to 400 μg/L with a detection limit of 0.57 μg/L. The relative standard deviation for ten replicate measurements of 10 and 300 μg/L of manganese(II) were 3.57 and 2.63 %, respectively. The proposed method was applied to tap, sea, river, and vegetable samples, and its accuracy was assessed through the analysis of certified reference water and recovery experiments.
研究领域:
分析化学
·
环境科学
✓ 已验证
DOI
TALANTA
·
2019
·
IF 4.916
Jiaqi He,Hui Zhi,Qi Hu,Hu Meng,Jihui Wang,Liang Feng
Detection of trace manganese (Ⅱ) ion (Mn 2+ ) is crucial to water safety. Here, commercially available PS-DVB microspheres were sulfonated and then filled into the SPE column in order to separate Mn 2+ from complex matrices. Meanwhile, europium (III) complex was prepared with a simple “one pot” method, and its fluorescence intensity was quenched gradually with the increase of Mn 2+ concentration. Europium (III) complex combined with home-made SPE column was utilized for highly selective and sensitive measurement of Mn 2+ . The detectable concentrations of Mn 2+ can be low as 0.2 μM, which was less than the drinking water guidelines. Consequently, this new method is promising to assess the content of Mn 2+ rapidly and accurately in real-world water samples.
研究领域:
分析化学
·
环境科学
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2019
·
IF 5.589
Zhangxiang Lin,Pei Yuan,Yuanyuan Yue,Zhengshuai Bai,Haibo Zhu,Tinghai Wang,Xiaojun Bao
Selective separation and recovery of Co(II)/Mn(II) from purified terephthalic acid (PTA) production wastewater is very important to reduce the Co(II)/Mn(II) catalysts consumption and control the pollutant discharge. This work employed zeolites NaA, NaX, and HZSM-5 with different pore sizes and Na(I) contents to selectively separate and recover Co(II)/Mn(II) from PTA wastewater and to understand the adsorption mechanism. It is found that only NaA can exclusively adsorb Co(II)/Mn(II) through ion-exchange without adsorbing any aromatic organic compound (AOC); oppositely, HZSM-5 shows the highest adsorption capacity for AOCs but almost no adsorption for Co(II)/Mn(II); and NaX exhibits moderate adsorption capacities for both Co(II)/Mn(II) and AOCs. Moreover, pH can significantly impact the adsorption of both Co(II)/Mn(II) and AOCs due to the competitive adsorption between H(I) and Co(II)/Mn(II) and the electrostatic repulsion between AOCs and zeolites. The adsorption kinetics, isotherms, and thermodynamics were also investigated to lay a good basis for process development. Importantly, bench-scale experiments for simulating the industrial operation were carried out, and the results show that the adsorption capacity of the NaA particles for Co(II)/Mn(II) from the industrial PTA wastewater is 9.1/8.6 mg/g, respectively, without adsorbing any AOC. Therefore, an efficient strategy to selectively separate and recover Co(II)/Mn(II) from PTA wastewater was successfully developed.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SPECTROSCOPY LETTERS
·
2015
·
IF 0.852
Yunfei He,Lifu Liao,Canhui Xu,Shijun Li,Rurong Wu,Yanyan Yang
The formation of a manganese (II) coordination supramolecular polymer was studied by resonance light scattering spectra for manganese (II) detection. Bis-sulfosalophen (a ditopic tetradentate Schiff base ligand) and bis-phenanthroline-glutaraldehyde (a ditopic bidentate ligand) were prepared for the construction of the supramolecular polymer. In a procedure of manganese (II) detection, manganese (II) ion reacts with bis-sulfosalophen to form a binuclear manganese (II) complex. The binuclear complex then self-assembles with bis-phenanthroline-glutaraldehyde to form the supramolecular polymer, resulting in the production of strong resonance light scattering signal. The amount of manganese was detected by measuring the resonance light scattering intensity. Under optimal conditions, a linear range was found to be 0.5–50.0 ng/mL, with a detection limit of 0.1 ng/mL. The method has been successfully applied to determine manganese in vegetable and tea samples with relative standard deviations of less than 5% and recoveries of 95.8–105.7%.
研究领域:
分析化学
·
超分子化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
·
2013
·Vol. 23
·期 6
·1451-1458
·
IF 1.174
Yu Xiaoke,Weng Wandan,Guo Xiaxia,Zheng Yueqing
Two polymeric carboxylato-bridged manganese(II) complexes, \( {}_{\infty }^{1} \) [Mn(bpe)(NBA) 2 ] ( 1 ) and \( {}_{\infty }^{1} \) [Mn(bpe)(MBA) 2 ] ( 2 ) (bpe = 1,2-di(4-pyridyl)ethylene; HNBA = m-nitrobenzoic acid; HMBA = m-methyl-benzoic acid), were synthesized and characterized. Compounds 1 and 2 are isostructural. X-ray diffraction studies show that the title compounds possess a double chain structure. The chains in 1 and 2 are assembled into 2-D layers via C–H···O hydrogen bonds interactions. Furthermore, owing to the offset face-to-face π–π stacking interactions, the adjacent 2-D layers embed into each other to form a 3-D supramolecular framework. Variable-temperature (2–300 K) magnetic susceptibility measurements show the presence of weak antiferromagnetic interactions between the high-spin Mn(II) (S = 5/2) ions through a carboxylato bridge with the best fit parameters for 1 being J = −0.13 cm −1 , zJ′ = −0.098 cm −1 and for 2 , J = −0.33 cm −1 , zJ′ = −0.001 cm −1 .
研究领域:
配位化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF PORPHYRINS AND PHTHALOCYANINES
·
2022
·
IF 1.914
Yiwen Yuan,Jianping Zhao,Jianfeng Li
Utilizing tetraphenylporphyrin (TPP), tetratolylporphyrin (TTP), tetramesitylporphyrin (TMP), and tetra- p -chlorophenylporphyrin (T p ClPP) as ligands, several five-coordinate high-spin p -toluenethiolate Manganese(II) complexes are isolated and studied by UV-vis, single-crystal X-ray and EPR spectroscopies. The crystal structures show noteworthy features including flexible axial p -toluenethiolate ligands and intramolecular C−H ⋅ ⋅ ⋅ π and π - π interactions between ligands and porphyrin planes. All four products are further studied by X-band EPR on both solid and solution states at 4 K which confirmed the S = 2/5 high-spin states. Temperature-dependent EPR and measurements with different equivalents of ligands are also reported for comparison. The work provides new references for the study of the active center of P450s and the biochemical reaction between cysteine residues and heme.
研究领域:
生物化学
·
配位化学
·
结构化学
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2015
·Vol. 44
·期 20
·9382-9390
·
IF 4.197
Qiang Yu,Yanhong Liu,Diansheng Liu,Jianfeng Li
Three five-coordinate, high spin manganese(II) “picket fence” porphyrin complexes, [Mn(TpivPP)(L)] (TpivPP = α,α,α,α-tetrakis(o-pivalamidophenyl)porphyrinato; L = 1-MeIm (1-methylimidazole), 1-EtIm (1-ethylimidazole) and 2-MeHIm (2-methylimidazole)), are synthesized and studied by single-crystal X-ray, UV-vis and electronic paramagnetic resonance (EPR) spectroscopy. Structural parameters are investigated and compared with analogues. Low temperature (90 K), high field EPR studies of [Mn(TpivPP)(1-MeIm)] and [Mn(TpivPP)(2-MeHIm)] showed five resonances including characteristic signals at ∼5.9 and ∼2.0. The simulations of the EPR spectra give the zero field splitting (zfs) parameters (D, E and λ) and the hyperfine coupling constant (A).
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TRANSITION METAL CHEMISTRY
·
2020
·Vol. 45
·期 6
·413-421
·
IF 1.366
Li Lingyan,Li Lei,Li Qianqian,Shen Yiming,Pan Shangke,Pan Jianguo
Two novel tetrahedral Mn (II) halide single-crystals [(C 7 H 10 N) 2 ][MnCl 4 ] ( 1 ) and [(C 7 H 10 N) 2 ][MnBr 4 ] ( 2 ), based on pyridine ionic liquids, have been successfully prepared. Centimeter-sized single crystal 2 was grown through bottom seed-solution temperature-lowering method, while the 1 was synthesized by solvent slow evaporation. Structure elucidation results indicate that the two crystals crystallize in the different space groups of the same monoclinic system. Significantly, the solid crystal 2 is possessed of superior luminescence properties than 1 at room temperature. Excited by ultraviolet light, the 1 and 2 emit intense green emission bands derived from the Mn (II) 4 T(G) energy level. The fluorescent lifetimes are 384.43 and 187.83 μs, respectively, and quantum yields are 82% and 12%, respectively. Furthermore, under the excitation of X-ray, the 2 exhibits prominent X-ray fluorescence performance.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
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