CHEMOSPHERE
·
2019
·
IF 5.108
Zhigang Wei,Yangfei Fang,Zhenrui Wang,Yue Liu,Yang Wu,Kai Liang,Jiahong Yan,Zhanchang Pan,Guanghui Hu
TiO 2 is one of the most cheap materials which can both adsorb arsenic and oxidize arsenite [As(III)] to arsenate [As(V)]. In this study, anatase TiO 2 crystals with different main facets such as {101}, {001} and {100} are synthesized and used to investigate arsenic adsorption kinetics, adsorption isotherms, photocatalytic oxidation (PCO) process and the pH effects. The adsorption kinetics of arsenic on TiO 2 crystals can be described by the pseudo second-order kinetic model. For the adsorption isotherms, the Langmuir model is better than the Freundlich model for arsenic on these TiO 2 crystals. For the PCO process, the rate of As(III) oxidation can be denoted by the pseudo first-order kinetic model. It should be noted that at neutral condition the adsorption and PCO rates of the three kinds of TiO 2 crystals follow the order of {101} > {001} > {100}. The pH effect is above all important for both the arsenic adsorption and its PCO. The highest PCO speed appears at high pH values such as at pH 11 or 12.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
JOURNAL OF FLUORESCENCE
·
2021
·Vol. 31
·期 4
·907-913
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IF 2.217
Li Huiqian,Xue Weijian,Wang Jinping,Ma Jie,Zhao Bing,Guo Xiangfeng
A novel substituted imidazole derivative 1a with carboxyl and quinoline structure has been designed and synthesized. And our initial discovery is that this compound can effectively detect water in ethanol. And the metal in solution couldn’t affect the absorption and fluorescence Spectra of 1a. With the addition of water, the energy band appears a red-shift from 330nm to 355nm in the absorption spectra. And the emission spectrum undergoes an important change in its fluorescent effect in the presence of water. Furthermore, absorption peak of 1a displays a red-shift with increasing pH from 2.31 to 10.72. All available data (absorption and emission) strongly support the possible mechanism. Due to the pronounced fluorescence changing property, the substituted imidazole derivative 1a could be utilized as fluorescent probes for detecting water in ethanol. Graphical Abstract
研究领域:
分析化学
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材料科学
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环境科学
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DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2012
·
IF 2.823
Xican Li
The original pyrogallol (1,2,3-trihydroxybenzene) method, which was developed specifically for superoxide dismutase, is now widely used for measuring superoxide-scavenging of other antioxidants. However, the strong pH effect has been ignored. In this study, the influencing factors have been systematically investigated for the first time, and a number of experiments have proved that the pH is of major importance. As major antioxidants contain carboxylic acid, ester, or lactone groups, pH 8.2 should be modified to physiological pH 7.4. The improved procedure is as follows. A pyrogallol solution (in 1 M HCl) is thoroughly mixed with pH 7.4 Tris-HCl buffer; A325 nm is measured every 30 s for 5 min at 37 °C. As the ΔA325 nm, control value reflects the initial concentration of substrate •O2–, it should be well controlled to guarantee the accuracy of the method. The improved pyrogallol method is a reliable and cheap superoxide-scavenging assay suitable for all types of antioxidants.
研究领域:
生物化学
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医学检验
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DOI
PubMed
高影响因子
Water
·
2019
·Vol. 11
·期 12
·2639
·
IF 2.524
Chi Wang,Zhian Ying,Ming Ma,Mingxin Huo,Wu Yang
The utilization of reclaimed water is a reliable and sustainable approach to enhance water supply in water-deficient cities. However, the presence of micro-organic pollutants (MPs) in reclaimed water has potential adverse effects on aquatic ecosystems and human health. In this study, we investigated the occurrence of 12 target MPs in the influent and reclaimed water collected from a local wastewater treatment plant, and the ultraviolet (UV)–chlorine process was applied to analyze its ability to remove MPs. The results showed that all 12 MPs were detected in both the influent and the reclaimed water, with the concentrations ranging from 25.5 to 238 ng/L and 8.6 to 42.5 ng/L, respectively. Over 52% of all the target MPs were readily degraded by the UV–chlorine process, and the removal efficiency was 7.7% to 64.2% higher than the corresponding removal efficiency by chlorination or UV irradiation only. The degradation efficiency increased with the increasing initial chlorine concentration. The pH value had a slight influence on the MP degradation and exhibited different trends for different MPs. The formation of known disinfectant byproducts (DBPs) during the UV–chlorine process was 33.8% to 68.4% of that in the chlorination process, but the DBPs’ formation potentials were 1.3 to 2.2 times higher. The toxicity assay indicated that UV–chlorine can effectively reduce the toxicity of reclaimed water.Keywords:MPs;UV–chlorine process;disinfectant byproducts;toxicity
研究领域:
环境科学
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水处理
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毒理学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2015
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IF 4.529
Pan Wang,Mingliang Du,Han Zhu,Shiyong Bao,Tingting Yang,Meiling Zou
Silica nanotubes (SNTs) with controlled nanotubular structure were synthesized via an electrospinning and calcination process. In this regard, SNTs were found to be ideal adsorbents for Pb(II) removal with a higher adsorption capacity, and surface modification of the SNTs by sym-diphenylcarbazide (SD-SNTs) markedly enhanced the adsorption ability due to the chelating interaction between imino groups and Pb(II). The pH effect, kinetics, isotherms and adsorption mechanism of SNTs and SD-SNTs on Pb(II) adsorption were investigated and discussed detailedly. The adsorption capacity for Pb(II) removal was found to be significantly improved with the decrease of pH value. The Langmuir adsorption model agreed well with the experimental data. As for kinetic study, the adsorption onto SNTs and SD-SNTs could be fitted to pseudo-first-order and pseudo-second-order model, respectively. In addition, the as-prepared SNTs and SD-SNTs also exhibit high adsorption ability for Cd(II) and Co(II). The experimental results demonstrate that the SNTs and SD-SNTs are potential adsorbents and can be used effectively for the treatment of heavy-metal-ions-containing wastewater.
研究领域:
材料科学
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环境科学
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DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Weiqing Zhou,Aiguo Zhou,Bing Wen,Peng Liu,Zhenli Zhu,Zou Finfrock,Jianwei Zhou
The environmental fate of antimony (Sb) is often strongly affected by adsorption, and the Sb isotope fractionation mechanism during adsorption has not been reported. Four batch experiments (kinetic, isothermal, effect of pH, and effect of coexisting anions) were conducted to evaluate the mechanism of Sb(V) adsorption to γ-Al 2 O 3 and the fractionation of Sb isotopes. Extended X-ray absorption fine structure (EXAFS) analyses show Sb(V) adsorption on γ-Al 2 O 3 occurs via outer-sphere surface complexation. The triple-layer model (TLM) effectively predicted the theoretical Sb adsorption amount under different pH conditions. The Sb isotope fractionation in the adsorption process can be divided into an initial kinetic stage (Rayleigh model, α adsorbed-aqueous = 0.99975 ± 0.00003) and subsequent isotopic equilibrium stage due to isotope exchange; however, no significant equilibrium isotope fractionation (Δ 123 Sb aqueous-adsorbed = ~0 ± 0.08‰) was evident by the end of the experiments. We propose the lack of significant equilibrium isotope fractionation in the effect of pH and isothermal experiments is due to Sb forming an outer-sphere complex on γ-Al 2 O 3. This study reveals Sb equilibrium isotope fractionation does not occur during Sb(V) adsorption onto γ-Al 2 O 3 , providing a reference for the future study of Sb isotopes and furthering understanding of the Sb isotope fractionation mechanism.
研究领域:
环境科学
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地球化学
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PubMed
高影响因子
MACROMOLECULES
·
2020
·
IF 5.918
Lei Cao,Qingqing Zhao,Qizhou Liu,Lei Ma,Chao Li,Xiyu Wang,Yuanli Cai
Electrostatic manipulation of triblock terpolymer nanofilm compartmentalization has been achieved via visible light-initiated reversible addition–fragmentation chain transfer aqueous dispersion polymerization of diacetone acrylamide monomer using cationic–neutral diblock copolymer macro-chain transfer agent (macro-CTA) at 25 °C. This photoinitiated polymerization-induced self-assembly (photo-PISA) evolves into two modes depending on solution pH. At pH 2.5, this macro-CTA dissolves in water with a fully cationic block; electrostatic repulsion leads to conventional aqueous photo-PISA and the formation of monolayer colloidal nanofilms. At pH 7.3, the cationic block transforms to a hydrophobic ionomer block with 10% cationic repeat units, and the copolymer chains self-assemble into weakly cationic micelles, which leads to seeded photo-PISA via self-assembly into discrete nanoclusters within the hydrophobic lamellar framework to form multicompartmentalized monolayer nanofilms. The nanoscale phase-separated 2D-confined nanoclusters and the lamellar structure can be tuned by the ABC/BAC block sequence, the degree of polymerization of the growing block, and the copolymer concentration. This electrostatic manipulation sheds new light on the rational design and preparation of multicompartmentalized block copolymer 2D nanoobjects.
研究领域:
高分子化学
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纳米材料科学
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物理化学
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DOI
高影响因子
FOOD CHEMISTRY
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2022
·
IF 9.231
Huanhuan Cui,Cuie Tang,Shan Wu,David Julian McClements,Shilin Liu,Bin Li,Yan Li
In this study, chitosan-based bigels were fabricated, where glycerol monolaurate was added in MCT oil to produce a gelled lipid phase and cinnamaldehyde was included in the lipid phase in order to act as a crosslinking agent. The synergistic effect of pH on chemical crosslinking effects was investigated. The potential of using these bigels as an alternative to cream was also investigated. The pH of the aqueous phase played an important role in controlling the extent of the Schiff-base reaction promoted by cinnamaldehyde. At pH 3.8, the bigels formed were homogenous but at pH 5.0 and 5.5 they exhibited phase separation, which highlighted the importance of chemical crosslinking. To better mimic the properties of real cream, span 80 was added to create a more homogeneous and smoother structure of the bigels. These bigels might provide a healthy and more sustainable alterative to food products that contain plastic fats, like cream.
研究领域:
食品科学
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生物材料
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化学工程
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DOI
PubMed
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Hanyu Wu,Jie Chen,Zengbo Su,Bin Ma,Yizhe Ji,Shuhan Lin,Dingfang Xu,Mingliang Kang
Europium(III), i.e., Eu(III), is chemically analogous to the trivalent lanthanides (Ln) and actinides (An). A good understanding of the adsorption behaviour of Eu(III) on mica group minerals is critical to the safety evaluation of the radioactive contamination. Nevertheless, the structural complexity of micaceous minerals makes it difficult to draw a consistent conclusion in the study of Eu(III) migration. In this work, we contrastively studied Eu(III) adsorption on dioctahedral muscovite and trioctahedral phlogopite as functions of pH, ionic strength, background electrolytes, interaction sequence, and fulvic acid (FA). Batch experiments showed that Eu(III) adsorption on both micas was strongly dependent on pH but quite independent on ionic strength that is determined by Na + . Planar sites are available on both muscovite and phlogopite while interlayer sites only on phlogopite under Na + and Ca 2+ electrolytes (not for K + and Cs + ). An interlayer expansion of phlogopite, as indicated by a newly appeared diffraction peak at ~6° 2-theta, occurred along with Eu(III) adsorption, which was also confirmed by transmission electron microscopy . Furthermore, the initial Eu(III) concentrations, the concentration ratios between Eu(III) and Cs + , and the reaction sequences of Eu(III)-electrolytes-FA affected both the adsorption behaviour of Eu(III) and reversely the structural alteration of phlogopite. The sequential extraction showed that the adsorbed Eu(III) was mainly in the ion-exchangeable form while the addition of FA could increase the portion of coordinative species. The currently proposed Eu(III) adsorption mechanism can shed new light on predicting the migration of Ln/An(III) at the mica-rich solid-liquid interface on a molecular scale.
研究领域:
环境科学
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放射化学
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矿物学
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DOI
PubMed
高影响因子
BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY
·
2025
·Vol. 115
·期 3
·1-7
·
IF 2.2
Wang Yun,Shan Ning,Habibul Zumrat,Habibul Nuzahat
This study investigated the impact of pH on the combined toxicity of polystyrene microplastics (MPs) and ciprofloxacin (CIP) on ryegrass growth and CIP uptake. Two different sizes of PS-COOH (200 and 500 nm) were utilized. The findings indicated that neutral and alkaline pH conditions (pH 7.0 and 8.8) significantly reduced CIP accumulation in ryegrass roots, regardless of MP presence. Conversely, CIP content in shoots (including leaves) increased with rising pH, showing 24.7-fold and 29.5-fold enhancements under CIP + 200 nm MPs and CIP + 500 nm MPs treatments at pH 8.8 compared to pH 5.3. Additionally, pH significantly influenced growth inhibition, with more pronounced effects at pH 7.0 and 8.8 than at pH 5.3. Under neutral and alkaline conditions, shoot lengths in 500 nm MPs + CIP and 200 nm MPs + CIP treatments were reduced to 50.3%, 69.7% and 86.8%, 81.3% of those at pH 5.3, respectively. These findings highlight the critical role of pH in modulating CIP uptake and toxicity in ryegrass, particularly in MP co-contaminated environments. Moreover, the relatively high CIP removal efficiency suggests the potential of ryegrass for CIP remediation in MP-polluted systems.
研究领域:
环境毒理学
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植物生理学
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污染生态学
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土壤生物学
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药物代谢
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环境化学
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生态风险评估
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
·
2022
·Vol. 44
·期 11
·4191-4200
·
IF 4.898
Kamran Muhammad Aqeel,Bibi Sadia,Chen Baoliang,Jiang Jun,Xu Ren-Kou
The consortium of minerals and organic matter notably alters and affects minerals' surface characteristics and nutrients providence. Organic matter such as biochar can modify the availability status of macronutrients like phosphorus (P). Despite some investigation, the adsorption/desorption of P with pure iron (hydr)oxides and the probable mechanisms involved are still unknown. In the present study, the goethite/hematite or goethite–biochar/hematite–biochar complexes were prepared, and a batch experiment with different P concentrations, time spell, pH, and ionic strength is performed to evaluate the sorption characteristics of P. The results of our study suggest that the P adsorption on mineral surface decreased with the increasing pH. Furthermore, the coexistence of biochar and minerals significantly inhibits P adsorption on the minerals surface. The results of Languimner and Freundlich's equations signify that the biochar–minerals complexes have heterogeneous adsorption sites and the presence of biochar reduces P adsorption on minerals surface. Among four biochars including peanut straw biochar (PC (B1)), rice straw biochar (RC (B2)), canola straw biochar (CC (B3)), and soybean straw biochar (SC (B4)), PC was more effective than other biochars to inhibit P adsorption on minerals surfaces. Graphical abstract
研究领域:
土壤化学
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环境地球化学
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农业环境科学
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生物地球化学
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固相界面过程
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DOI
高影响因子
ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
·
2022
·Vol. 45
·期 6
·2905-2915
·
IF 4.898
Zhang Xiaolei,Liu Lu,Chen Xiaoli,Li Ji,Chen Jiaxin,Wang Hongjie
With huge amount of plastic entering to the environment, microplastic pollution has become a great concern. Microplastic behavior in the environment is important to evaluate its harm to ecosystem and human beings. It has been found that microplastic can be used as a carrier to adsorb and enrich heavy metals or organic pollutants in water or soil. With the development of industry and medicine, antibiotics are improperly used in many countries and most of them end up in wastewater. This study investigates the adsorption behavior of sulfamethoxazole (SMX) antibiotic onto virgin and aged polyamide 6 (PA6) microplastics. The maximum adsorption amount was 0.089 mg SMX/g PA6 at 25 °C and pH 7 with initial SMX concentration of 2 mg/L. Results reveal that the adsorption was mainly due to the chemical bounding. The impact of pH, salinity, and humic acid on the adsorption have been studied, and it was found that the pH has significant impact on the adsorption. At pH 5, the adsorption amount was 0.27 mg/g which is two times higher than that at pH 7. The SMX adsorbed on PA6 tends to be more likely desorbed in reservoir water than in ultrapure water. For instance, the desorption amount of SMX from virgin PA6 was 0.15 mg/L in reservoir water but 0.10 mg/L in ultrapure water. The study indicates that microplastics have great threat to environment.
研究领域:
环境科学
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生态毒理学
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水污染
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材料科学
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化学风险评估
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）