ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
·
2024
·Vol. 46
·期 12
·1-17
·
IF 3.2
Liu Anrong,Feng Li-Juan,Ou Yangyang,Zhang Xiaoya,Zhang Jinhong,Chen Hongyan
Biochar has been widely used to solve the wastewater pollution of polycyclic aromatic hydrocarbons (PAHs). However, the competition of PAHs with different benzene ring numbers (e.g., phenanthrene [Phe], pyrene [Pyr], and benzo[a]pyrene [BaP]) for adsorption sites on biochar has received little attention. In this study, biochar was produced by co-pyrolysis of sludge and phosphorus tailing at different temperatures (300, 500, or 800 °C) to adsorb PAHs. The results show that phosphorus tailing increased the adsorption of PAH by increasing the biochar’s BET surface area (S BET ), micropore volume, hydrophobicity (at low temperatures) and aromaticity (at high temperatures). The maximum adsorption capacities were 29.90 µmol/g for Phe, 25.58 µmol/g for Pyr and 20.45 µmol/g for BaP, respectively. Importantly, the types and functions of groups involved in the adsorption of various PAHs were discussed. Adsorption of Phe and Pyr on the biochar mainly involved C=O and C–O–C functional groups, and there was a certain degree of competition between these PAHs for those sites. In contrast, BaP mainly adsorbed at C–OH and C=C moieties, without competing with Phe or Pyr at C–OH sites. The competitive edge of BaP was also stronger than that of Phe and Pyr on C=C functional groups. The adsorption mechanisms involving pore filling, hydrophobic interactions, and π – π interactions governed the adsorption of the evaluated PAHs. Overall, the adsorption of PAHs on biochar followed a heterogeneous chemical adsorption process.
研究领域:
环境科学
·
化学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Congqing Yang,Chao Gao,Hu Li,Mingxi Pan,Hui Huang
Silver-coated aluminum powder (Al/Ag) are anticipated to replace Ag powder in industrial production. However, the high activity of Al powder and insufficient understanding of the Ag deposition mechanism pose challenges in effectively controlling the Ag deposition process and morphology, thereby restricting which its applications. In this article, a diffusion-deposition competition mechanism is proposed to explain the growth path of Ag atoms on Al surfaces. This mechanism posits that the growth pathway of Ag atom is governed by the ratio between the surface diffusion rate and the deposition rate (V diffusion /V deposition ). Specifically, when surface diffusion dominates (V diffusion /V deposition ≫1), Ag atoms form a conformal layer, whereas the deposition-controlled (V diffusion /V deposition < 1 or V diffusion /V deposition ≪1), Ag atoms tend to form chains or clusters. Surface diffusion must be considered in regulation crystal growth process. By understanding this mechanism, Ag/Al particles with excellent electromagnetic wave (EMW) absorption properties (RL min = −37.8 dB, EAB max = 4.4 GHz) can be prepared simply by controlling only the experimental conditions that affect the surface diffusion and deposition rates. The insights gained from the proposed mechanism offer new ideas for the preparation of other noble metals or inorganic materials.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2025
·
IF 17.7
Yao Yao,Juping Xu,Minhua Shao
Hydrogen evolution reaction (HER) is unavoidable in many electrochemical synthesis systems, such as CO 2 reduction, N 2 reduction, and H 2 O 2 synthesis. It makes those electrochemical reactions with multiple electron-proton transfers more complex when determining kinetics and mass transfer information. Understanding how HER competes with other electrochemical reduction reactions is crucial for both fundamental studies and system performance improvements. In this study, we employed the oxygen reduction reaction (ORR) as a model reaction to investigate HER competition on a polycrystalline-Au surface, using a rotating ring and disk electrode. It’s proved that water molecules serve as the proton source for ORR in alkaline, neutral, and even acidic electrolytes, and a 4-electron process can be achieved when the overpotential is sufficiently high. The competition from H + reduction becomes noticeable at the H + concentration higher than 2 mmol L –1 and intensifies as the H + concentration increases. Based on the electrochemical results, we obtained an equivalent circuit diagram for the ORR system with competition from the H + reduction reaction, showing that these reactions occur in parallel and compete with each other. Electrochemical impedance spectroscopy measurements further confirm this argument. Additionally, we discover that the contribution of H + mass transfer to the total H + reduction current is significant and comparable to the kinetic current. We believe this work will deepen our understanding of HER and its competition in electrochemical reduction systems.
研究领域:
电化学
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材料科学
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能源化学
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产品关联
DOI
高影响因子
CRYSTAL GROWTH & DESIGN
·
2024
·
IF 3.2
Detao Li,Wenqian Chen,Limin Zhou,Li Xu,Feiqiang He,Jerry Y Y Heng,Hamza Shehzad,Jinbo Ouyang
Understanding drug cocrystal formation and its competitive mechanism is important for improving the physicochemical properties of drugs. In this article, the cocrystal formation of polyhydroxy natural products and their competitive mechanisms are discussed through experimental screening and theoretical calculations. The formation conditions and types of cocrystals were determined based on efficient screening experiments of polyhydroxy natural product cocrystals. To investigate the difficulty and stability of cocrystal formation, competitive cocrystal experiments of polyhydroxy natural products were carried out simultaneously. By simulation of the electrostatic potential surface of molecules and the Hirshfeld surface of crystals, the mode of hydrogen bonding within the crystals was determined. The strength of hydrogen bonding was assessed based on the intermolecular interactions and energy framework within the crystal structure. A “substitution model” was constructed based on experimental results and theoretical calculations, which is of great significance for the prediction and design of natural product cocrystals and provides a feasible solution for improving the physicochemical properties of drugs.
研究领域:
药学
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化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Shipeng Tang,Han-jian Hu,Xinyi Chang,Hongyan Zhang,Yu Chen,Yicheng Li,Wei-xiong Li,Xiaolong Hu,Xiaoyong Liao,Gang-Biao Jiang
Rational utilization of the competition among internal functional groups in chemical adsorbents for heavy metal ions can significantly enhance adsorption efficiency, while also driving the development of advanced adsorbents. This study proposes an innovative strategy employing a group competition mechanism to develop a dual-function platform for Cd(II) detection and adsorption, along with field detection applications. Nitrogen-doped graphene quantum dots (NGQDs) anchor the Cd(II) detection agent, 5,10,15,20-tetrakis(1-methyl-4-pyridinio)porphyrin tetra( p -toluenesulfonate) (TMPyP), onto sodium alginate chains to form an aerogel (T-NGQDs-CAA). FT-IR and XPS characterizations confirm that NGQDs facilitate a rapid Cd(II) transfer pathway through electrostatic interactions and π-π stacking. The Cd(II) detection speed of T-NGQDs-CAA is enhanced fivefold, while density functional theory analysis reveals that TMPyP exhibits a significantly stronger binding affinity toward Cd(II) compared to nitrogen- and oxygen-containing groups. Combined experimental and theoretical analyses demonstrate that this rapid ion transfer pathway intensifies TMPyP’s competition for Cd(II), thereby promoting the coordination reaction between TMPyP and Cd(II). Additionally, the Cd(II) adsorption by T-NGQDs-CAA follows the pseudo-second-order kinetic and Langmuir isotherm models, exhibiting a 148.7% increase in saturation adsorption capacity. This strategy, through constructing rapid ion channels with NGQDs and leveraging the group competition mechanism, enables in-situ Cd(II) detection and removal, enhancing the understanding and application of interactions between functional groups and metal ions.
研究领域:
环境科学
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材料科学
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化学
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DOI
高影响因子
Biosensors-Basel
·
2025
·Vol. 15
·期 5
·291
·
IF 5.6
Yawen Zhu,Xuemei Wang,Zhiyong Yan,Feifei Zhang,Jianfei Xia,Lili Lv,Zonghua Wang
The dual-signal output self-calibration mode reduces the false positive and negative signals of electrochemiluminescence (ECL) aptamer sensors. A competitive dual-signal ECL platform was designed for the ultrasensitive detection of kanamycin (KAN) using a zirconium metal–organic framework (Zr MOF) and Luminol as ECL emitters. To enhance the ECL efficiency, a co-reactant (polyethyleneimine, PEI) was covalently bound to the Zr MOF to achieve self-enhanced ECL. Based on the selective interaction between KAN and its aptamer, the Luminol/KAN/Zr MOF-PEI “sandwich” structure was immobilized on the electrode surface. The competition for PEI between emitters increased the Luminol ECL signal and decreased the Zr MOF’s ECL signal. The ratio in ECL signals between the two competitive emitters enabled the quantitative analysis of KAN, achieving a detection limit as low as 7.86 × 10−4ng/mL. This study elucidated the synergistic mechanism between self-enhanced ECL and ECL competition, offering a novel approach for constructing dual-signal ECL sensors using a single co-reactant.
研究领域:
分析化学
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生物传感
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环境科学
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DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2023
·
IF 4.5
Yucheng Liu,Haoran Sun,Jing Hou,Jinyin Bai,Lizhang Wang
In this work, β-PbO 2 /Ti and RuO 2 -IrO 2 /Ti anodes and Ti cathodes were employed to conduct electrocatalytic phenol degradation experiments at various current densities. The difference in degradation rates between the two anodes indicated that the oxygen evolution reaction (OER) is related to the organic matter concentration. Consequently, a coupling mechanism “active-site competition mechanism (ACM) + adsorbate evolution mechanism (AEM)” for anodic oxygen evolution was described. Based on this mechanism and experimental results, it can be concluded that the ACM influences the initial degradation rate, and the AEM affects final organic matter concentrations. DFT calculations showed that RuO 2 -IrO 2 exhibits excellent AEM activity attributed to the lower OER overpotential (0.7 V) and stronger adsorption energies of *O oxygenated intermediate (-1.52 eV). At the same time, RuO 2 -IrO 2 possesses slight thermodynamic reaction energy of ACM, which are 103.3, 31.6 and 89.5 kJ/mol. Therefore, the slower degradation rates and lower removal efficiency on RuO 2 -IrO 2 /Ti are owing to the better ACM and AEM activity. Then, electrocatalytic experiments at various pH were conducted to verify the conclusion that AEM affects final organic matter concentrations. Finally, this work has implications for a better understanding of the OER mechanism and provides theoretical guidance for improving the removal efficiency of organic pollutants.
研究领域:
环境科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2019
·
IF 5.714
Xing Cao,Weibing Wang,Rui Ma,Shichang Sun,Junhao Lin
In order to exhaustively investigate the physical and chemical mechanisms of heavy metal immobilization in sludge incineration residue (SIR)-based magnesium potassium phosphate cement (MKPC), this work investigated the influence of Pb 2+ and Zn 2+ on the compressive strength and microstructure of SIR-based MKPC, and the efficiency of Pb and Zn immobilization. Taking the difference of Ksp (solubility product) of different heavy metal compounds as the entry point, the physical and chemical mechanisms of Pb and Zn immobilization, and the competitive mechanism between coexisting ions, were comprehensively analyzed. It was discovered that Pb 2+ is in the form Pb 3 (PO 4 ) 2 , and Zn 2+ is immobilized in the form Zn 2 (OH)PO 4 [Zn 3 (PO 4 ) 2 is preferentially formed, when the pH > 7, Zn 3 (PO 4 ) 2 is converted to Zn 2 (OH)PO 4 ]. The low solubility of heavy metal phosphates is the main reason that Pb 2+ and Zn 2+ are well immobilized. The preferential formation of Pb 3 (PO 4 ) 2 (K sp = 8 × 10 −43 ) and Zn 3 (PO 4 ) 2 (K sp = 9.0 × 10 −33 ) reduced the amount of MgKPO 4 ·6H 2 O (K sp = 2.4 × 10 −11 ), resulting in a decrease in compressive strength. Besides, coexisting Pb 2+ and Zn 2+ has a competitive effect: Pb 2+ will weaken the immobilization efficiency of Zn 2+ . The new exploration of these mechanisms provide a theoretical basis for rationally adjusting the Magnesia/Phosphate ratio to enhance the compressive strength and improve the efficiency of heavy metals immobilization.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
PubMed
高影响因子
ANALYST
·
2021
·Vol. 146
·期 16
·5115-5123
·
IF 4.616
Haiyang Yao,Difei Jiang,Gaoqiu Dong,Jiamin Sun,Shasha Sun,Lingling Li,Fenfen Zheng,Weiwei Xiong
Dynamically monitoring intracellular glutathione (GSH), a crucial biomarker of oxidative stress, is of significance for the diagnosis and treatment of certain diseases. Although manganese dioxide (MnO2) based GSH fluorescent sensors have exhibited high sensitivity and good selectivity owing to the specific reactivity between GSH and MnO2, near-infrared (NIR) MnO2 based nanoprobes for GSH detection are scarce. Herein, we have developed a NIR activatable fluorescence nanoprobe for the imaging and determination of intracellular GSH based on a core–shell nanoparticle, consisting of NIR emitted gold nanocluster doped silica as the fluorescent core and manganese dioxide as the GSH-responsive shell (named AuNCs@MnO2). Due to the absorption competition mechanism, the outer MnO2 shell rather than the inner AuNCs core preferentially absorbed the excitation light, thus leading to fluorescence quenching of the inner AuNCs core. Upon addition of GSH, the fluorescence of the nanoprobe restored along with the reduction of MnO2 to Mn2+ because of the absorption competition disappearance-induced emission. The activatable fluorescence linearly increased upon changing the GSH concentration in the range of 2 to 5000 μM with a detection limit of 0.67 μM. The cytotoxicity test shows that the AuNCs@MnO2 nanoprobes have a good biocompatibility. After entering the cancer cells, the intracellular GSH degraded the outermost MnO2 shell and initiated the NIR fluorescence restoration of AuNCs, which can be used to monitor the dynamic change of intracellular GSH. This strategy provides an NIR-activatable way to detect GSH levels in living cells and offers a promising platform for the diagnosis and treatment of GSH-related diseases.
研究领域:
生物医学工程
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纳米技术
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分析化学
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细胞生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Zizhao Fu,Jie Zhao,Rui Jiang,Shiliang Mei,Wanlu Zhang,Ruiqian Guo
I-III-VI alloyed quantum dots (QDs) have shown great application potential in many fields. At present, Al-based alloyed QDs have become a kind of ideal material of the color conversion layer of WLEDs because of their blue-emission, abundant raw material content, and the strong stability of Aluminum oxides. In this study, we synthesized blue-emitting CuAlSe 2 /ZnSe QDs and dual-emitting CuAlGaSe/ZnSe QDs by using hot-injection and one-pot method respectively, with a photoluminescence quantum yield (PL QY) of 46.75% and 68.79%. Their spectral tuning effect and the luminescence mechanism were investigated and discussed by changing the elemental molar ratios and nucleation temperature. By changing the Cu/(Al+Ga) and Al/Ga molar ratio, the emission wavelength of CuAlGaSe/ZnSe QDs was adjustable from 456 nm to 631 nm, with the Al and Ga competition mechanism in CuAlGaSe/ZnSe was also proposed. Finally, a single-component dual-emission CuAlGaSe/ZnSe WLED with a color rendering index (Ra) of 91.4 was prepared. This work demonstrated the superior fluorescence performance of multi-component QDs and the potential application of Al-based QDs in WLEDs.
研究领域:
材料科学
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纳米技术
·
光电子学
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固态照明
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光谱学
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量子点
·
合金半导体纳米晶体
✓ 已验证
产品关联
DOI
高影响因子
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