CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Wei Feng,Mo Zheng,Jin Bai,Xianxian Zhang,Chuang Wu,Zhenxing Guo,Lingxue Kong,Zongqing Bai,Wen Li
Understanding the effects of co-pyrolysis synergies between low-rank coal and high-density polyethylene (HDPE) on the carbon structure evolution in char and the relationship between char structure and chemical bonds evolution is very needed. A combination of ReaxFF MD and experimental approaches provides an opportunity for fully understanding the dynamic profiles of char structures and coking trends during co-pyrolysis process of coal and HDPE. In this work, consistent conclusions were obtained from fixed-bed experiments and ReaxFF MD simulations in product distribution during both individual coal pyrolysis and co-pyrolysis at different temperatures. The ReaxFF MD simulation results reveal that adding HDPE partially inhibited the coking process of coal char. The RDF results indicated higher order degree and aromaticity exist in coal/HDPE(7:3)-Char when compared to those in coal-Char, which agrees well with the findings from XRD and FTIR approaches. By analyzing the evolution of C=C, C=O, C-O, C( sp 2 )-C( sp 3 ), C( sp 3 )-C( sp 3 ) and C( sp 2 )-H bonds in C 40 + fragments during secondary simulations of co-pyrolytic char, it was observed that the structural order and aromaticity of co-pyrolytic char increase with temperature, and the oxygen-containing bonds are the initial recombination sites for char formation. These findings provide rich theoretical information to complement the understanding of char structure in co-fed systems and the interaction between coal and HDPE blend.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Wei Feng,Mo Zheng,Lijun Jin,Jin Bai,Lingxue Kong,Huaizhu Li,Zongqing Bai,Wen Li
Co-pyrolysis of waste plastics and low-rank coal is a promising approach to deal with the serious waste crisis and improve the clean utilization of low-rank coal. In this work, the comprehensive co-pyrolysis behaviors of low-rank coal and polyethylene plastics were explored systematically by combining TG experiment, in-situ Py-TOF-MS technique, and ReaxFF MD simulation. The consistent results were obtained among three approaches to demonstrate the positive interaction exists between coal and PE during the co-pyrolysis process, which leads to volatile yield increasing with PE addition. TG experimental results showed that the blending ratio of 7:3 for coal and PE has the strongest synergy during the co-pyrolysis process, while Py-TOF-MS experimental results unraveled that the synergistic effect of coal and PE was determined by changing the content of pyrolysis products rather than by producing cross-reaction products. The PE addition significantly reduced the yield of MAHs and normal alkyl-substituted monophenols and increased the yield of olefins, alkanes, and aromatic derivatives. ReaxFF MD simulation results complement the experimental observation to obtain similar weight loss profiles with TG experiments and consistent identification of major representative tar pyrolyzates with Py-TOF-MS experiments. Particularly, the detailed gas evolving trends and the underlying bond-breaking reactions of C C, C O, and C H bonds were revealed by ReaxFF MD, which indicates PE addition promotes bond breaking of C C and C H to enhance more tar generation. The combination of experiments and ReaxFF MD simulations can capture the comprehension of the co-pyrolysis process between low-rank coal and PE, which can be extended to other co-pyrolysis applications for related solid fuels.
研究领域:
能源与燃料化学
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CEMENT AND CONCRETE RESEARCH
·
2024
·
IF 10.9
Ya-Jun Wang,Xiao-Pei Zhang,Dong-Mei Liu,Jun-Guo Li,Jian-Bao Zhang,Yu-Wei Zhang,Ya-Nan Zeng,Yi-Tong Wang,Bao Liu,Xi Zhang,Ya-Jing Zhang
Ca 2 SiO 4 is the primary carbonation-reactive mineral in steel slag, and demonstrates significant carbon sequestration potential, yet its microscopic reaction processes remain unclear. This study investigated the carbonation behavior of Ca 2 SiO 4 using ReaxFF MD simulations. The results indicated that as CO 2 concentration increased, the capture rate of Ca 2 SiO 4 decreased, and the molecular structure of the resulting CaCO 3 varied in oxygen origin. At room temperature, the carbonation rate of Ca₂SiO₄ gradually decreased over time until it reached equilibrium. Increasing the temperature could reactivate the carbonation, but the rate would still decline until it reached equilibrium again. Higher temperatures could accelerate the formation of the intermediate C 2 O 5 2− and internal CO 3 2− diffusion, thereby boosting the carbonation and increasing CO 2 adsorption. This study investigated the carbonation of Ca 2 SiO 4 at the atomic level, aiming to link microscopic molecular processes with macroscopic experimental phenomena, thereby providing a theoretical foundation for enhancing the carbonation efficiency of steel slag.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Yang Li,Jing Xu,Fuwei Sun,Yanan Guo,Daoying Wang,Tianfu Cheng,Minwei Xu,Zhongjiang Wang,Zengwang Guo
The interaction mechanism between soybean protein isolate (SPI) and furan flavor compounds with different structures is studied using spectroscopy, molecular docking , and MD simulation methods. The order of binding ability between SPI and furan flavor compounds is 2-acetylfuran>furfural>5-methylfurfural. The structural differences (position and quantity of methyl groups) of three furan flavor compounds are key factors leading to the different adsorption abilities of SPI for furan flavor compounds. The findings from spectroscopy analyses suggest that the interaction between SPI and furan flavor compounds involves both static and dynamic quenching mechanisms, with static quenching being the main factor. Molecular docking and MD simulations reveal the atomic-level mechanisms underlying the stable binding for SPI and furan flavor compounds at spatiotemporal multiscale. This study provides a theoretical framework for the production and adjustment of meat essence formula in the production of soybean protein-based meat products.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2024
·
IF 5.8
Hongdi Yu,Fawei Lin,Xuan Guo,Chujun Luan,Eslam Salama,Mona Ossman,Xinghua Liu,Rundong Li,Jiantao Li,Lei Che,Wangyang Tian,Beibei Yan,Guanyi Chen
Pyrolysis of oily sludge (OS) possesses dual advantages of oil recovery and harmless treatment. Exploring the reaction pathway for petroleum hydrocarbons during pyrolysis in the presence of minerals is critical for optimizing pyrolysis parameters. This study selected six pure soil minerals and five typical oil compounds as representative to simulate OS samples. Model compounds are more helpful deriving and clarifying the internal mechanism. The mixed oil compounds were continuously loading fed into reactor loaded with varied minerals, which was facilitated the detection of pyrolytic products. Meanwhile, the pyrolysis reaction pathways of oil compounds at different temperature and pressure were simulated by ReaxFF MD. According to the experimental results, high temperature increased the content of light hydrocarbons and gas products (i.e., C 3 H 4 , C 4 H 8 , CH 4 , and H 2 ). Montmorillonite (MT) and illite (IT) exhibited catalytic ring-opening and cracking effects as alkaline minerals, while the kaolin (KL) presented catalytic aromatization effects. The catalytic ring-opening effect of calcite (CA) and hematite (MA) was equally evident, but quartz (QA) possessed a weak catalytic effect and even promoted condensation . n-Dodecane (ND) and 1-dodecene (1-DE) had more complicated pathways compared to other com-pounds with stable rings. The main cracking reaction pathway of ND was the breakage of β C C bond, and the C C bond at both ends was easier to break than the one in the middle. The pyrolysis reaction pathway of 1-DE not only included the breakage of β C C bond, and the generation of ethyl radicals. The methyl groups in methylcyclohexane (MC), methylbenzene (MB), and 1-methylnaphthalene (1-ME) could be detached, while ring-opening reactions generated free radicals . This work provides detailed explanation of pyrolysis reaction pathway of oil compounds and the catalytic mechanism of soil minerals, which helps us understand OS pyrolysis process.
研究领域:
环境化学
·
能源工程
·
石油污染治理
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热解机理
·
计算化学
✓ 已验证
DOI
高影响因子
TRIBOLOGY INTERNATIONAL
·
2021
·
IF 4.872
Hongxiang Yu,Zhiwen Zheng,Haijie Chen,Dan Qiao,Dapeng Feng,Zhenbin Gong,Guojun Dong
The tribochemical reaction rate of multiply alkylated cyclopentane (MAC) was studied from the perspective of tribo-oxidation. The activation energy of MAC oxidation reaction and respective decrease of activation energy owing to catalysis from iron and Fe 3 O 4 were determined by means of auto-oxidative tests. The sum of the reduced activation energy due to iron and Fe 3 O 4 was less than that in tribological test, which highlighted the crucial role of shear stress in accelerating tribo-oxidation reaction. Additionally, the experimental process was replicated by utilizing reactive molecular dynamics (MD) simulations. The simulation results revealed the significance of shear stress in tribo-oxidation reaction and the catalytic mechanism of iron, Fe 3 O 4 , and shear stress for promoting oxidation reaction was interpreted.
研究领域:
摩擦学
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化学动力学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 6
·1338
·
IF 4.2
Zhi Qu,Lin Zhang,Yan Sun
PETase exhibits a high degradation activity for polyethylene terephthalate (PET) plastic under moderate temperatures. However, the effect of non-active site residues in the second shell of PETase on the catalytic performance remains unclear. Herein, we proposed a crystal structure- and sequence-based strategy to identify the key non-active site residue. D186 in the second shell of PETase was found to be capable of modulating the enzyme activity and stability. The most active PETaseD186Nimproved both the activity and thermostability with an increase inTmby 8.89 °C. The PET degradation product concentrations were 1.86 and 3.69 times higher than those obtained with PETaseWTat 30 and 40 °C, respectively. The most stable PETaseD186Vshowed an increase inTmof 12.91 °C over PETaseWT. Molecular dynamics (MD) simulations revealed that the D186 mutations could elevate the substrate binding free energy and change substrate binding mode, and/or rigidify the flexible Loop 10, and lock Loop 10 and Helix 6 by hydrogen bonding, leading to the enhanced activity and/or thermostability of PETase variants. This work unraveled the contribution of the key second-shell residue in PETase in influencing the enzyme activity and stability, which would benefit in the rational design of efficient and thermostable PETase.
研究领域:
生物化学
·
酶学
·
塑料降解
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Jianfang Yang,Xiaoyun Hu,Tianshi Zhang,Juhui Liu,Haonan Zhang,Xiaoyang Liang,Qingqing Guan
Filtration is a pivotal industrial technology that enables the efficient separation and purification of multiphase systems while optimizing resource utilization, improving operational efficiency, and addressing environmental sustainability challenges. However, developing filtration systems that deliver high clarity and rapid filtration rates, while resisting surface cracks in multiphase unstable polysilicon slurry remains a significant challenge. In this work, a cellulose-modified diatomite-based dipole-interaction-enhanced (CE@D-IE) strategy, characterized by its straightforward yet highly effective, was proposed as a solution to the issue. The CE@D-IE filtration system prevented filter cake from surface cracking at 10-40 °C, attributed to diatomite's capillary resistance, cellulose-enhanced dipole interactions, and chain entanglement. Atomic force microscopy (AFM) and molecular dynamics (MD) simulations further revealed stronger interaction within the filter cake formed by the CE@D-IE strategy, providing critical molecular-level evidence for its improved resistance to surface cracking. Furthermore, the CE@D-IE strategy achieved excellent filtrate clarity and demonstrated a 50% improvement in filtration rate compared to the BF strategy, resulting in a comprehensive enhancement of polysilicon slurry filtration performance . This work provides a viable and practical solution to address filtration challenges in polysilicon slurry under complex and dynamic conditions, while also demonstrating significant potential to enhance filtration performance in other complex systems.
研究领域:
化学工程
·
材料科学
·
环境工程
·
纳米技术
·
分离技术
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Weizhi Liu,Yongqiang Guo,Zhiwei Xue,Hao Sun,Xiaofeng Lin,Chao Liu
Polyvinylidene fluoride (PVDF) membrane is a cheap and commonly used separation material, but its inherent hydrophobicity results in significant membrane contamination, which limits its engineering application and further development. The hydrophilic PVDF-g/co-NVP membrane was prepared through low-dose γ-ray irradiation and using N-vinyl-2-pyrrolidinone (NVP) as a modifier in this study. The effects of γ-ray dose and incorporating NVP additive on the microstructure, hydrophilicity, anti-fouling capability, and mechanical capacity of membranes were discussed. Molecular dynamics (MD) simulation method was used to comprehensively investigate the impact of the NVP on the physicochemical characteristics of membrane structure. Under a specific NVP load, the water contact angle of the membrane decreases from 87.92° to 52.66°. The pure water permeance reaches 362.1 L/m 2 h, and the porosity increases to 55.21 %±1.29 %, which indicates that γ-ray irradiation with NVP addition can effectively adjust the pore structure and hydrophilicity of the membrane. During anti-fouling test against bovine serum albumin (BSA), the modified membrane exhibits remarkable anti-fouling characteristics, including reduced BSA accumulation, enhanced flux recovery, lower irreversible contamination level, and extended cleaning cycle compared with the original pure PVDF membrane because of its higher hydrophilicity and positive zeta-potential value. This study elucidates the mechanism underlying γ-ray graft modification of PVDF membranes, thereby providing valuable insights into the development of efficient functional membrane materials.
研究领域:
材料科学
·
环境工程
·
化学工程
·
膜技术
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULES
·
2021
·
IF 5.985
Yongsheng Luo,Chu Wang,Ai-Ping Pang,Xiang Zhang,Dayang Wang,Xiaolin Lu
The interfacial molecular structures of polyelectrolyte brushes grafted on solid substrates are generally influenced by the electrostatic interaction and osmotic pressure. Although the hydrated structures of the strong polyelectrolyte brushes are considered less sensitive to salts present in the surrounding environment at low concentrations, the salts may still influence the distribution of polyelectrolyte counterions and interfacial network structures of water molecules nearby, thereby being correlated to the dissociation of the polyelectrolyte chain segments bound on solid substrates and the entire chain conformation. In this study, sum-frequency generation (SFG) vibrational spectroscopy and coarse-grained molecular dynamics (MD) simulation are combined to investigate the interfacial molecular structures of a strong polyelectrolyte, polystyrene sulfonate (PSS), grafted on silica substrates. The dynamic responses of the OH stretching signals of the interfacial water for the PSS brushes in low-concentration salt solutions bearing monovalent (Na+ and K+), divalent (Ca2+), and trivalent (Y3+) cations are monitored via a connected SFG/microfluidic chip system. First, the salts enhanced the ordering of interfacial water structures irrespective of the nature of cations, reflecting the enlarged electric potential owing to the diffusion of ions and the dissociation of the PSS segments near the solid substrate. Second, the dynamics to reach the final interfacial structural equilibrium appears to be dependent on the type of cations, showing a two-step process and thus presenting evidence for the initial ion diffusion and subsequent dissociation of the chain segments near the substrate wall. Meanwhile, it was found that divalent and trivalent cations caused electrostatic bridging among the polyelectrolyte brush segments, leading to a more disordered chain conformation. We therefore believe that this report provides a fundamental understanding of the interfacial structural and structural transition features with respect to the polyelectrolyte brushes at the molecular level.
研究领域:
材料科学
·
表面化学
·
物理化学
·
高分子科学
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2025
·
IF 6.3
Haitao Zhang,Hailong Kang,Shuang Ma,Qirong Yang,Youping Li,Chenxuan Yan,Xinsong Wang,Yong Dong
Composite chloride salts have become molten salt heat storage materials with high development potential due to their excellent heat storage performance. Since chloride salts are prone to leakage, they need to be adsorbed onto porous materials to prepare composite phase change materials (CPCMs). Changes in the pore size of porous materials will lead to changes in the scale of chloride salts. Currently, there is little research on the impact of scale variation on the thermophysical and phase change characteristics of composite chloride salts, and the underlying mechanisms are not yet clear. With the ZnCl 2 -NaCl-KCl (3:1:1 mol%) eutectic salt as the phase change material (PCM), this study integrates molecular dynamics (MD) simulation with an experimental approach to investigate the impact of scale on the thermophysical properties and phase change properties of CPCM. The inherent influence mechanism of scale effect is analyzed from a microscopic perspective. The results indicate that as the scale increases, the interaction energy between molecules within the system gradually increases, and the system structure becomes more compact. The thermal conductivity first increases and then decreases, reaching a maximum of 0.45 W/(m·K) at 8 nm; the volumetric thermal expansion coefficient gradually decreases. As the scale increases from 3 nm to 15 nm, the melting temperature rises by 8.1 %, while the solidification temperature decreases by 1.73 %, resulting in a significant increase in the degree of supercooling. The latent heat gradually increases with scale, which is consistent with the coordination number.
CAS / MDL:
研究领域:
材料科学
·
热能工程
·
储能技术
·
分子动力学模拟
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Xu Liu,Yuan Zhao,Cong Gao,Xiaohuan Sun,Shixin Li,Jie Han
Understanding the unique role of supramolecular chirality in nano-protein/cell interactions, as opposed to molecular chirality, is crucial for elucidating the origin of life. However, this aspect has received inadequate attention. In this study, L/D-glutamic acid-based amphiphiles (L/D-GluC16), which possess molecular chirality, were synthesized. Additionally, through the manipulation of solvent effects, left/right-handed helical nanofibers ( M / P -GluC16), endowed with supramolecular chirality, were assembled from L/D-GluC16. With the aid of molecular dynamics (MD) simulations, the interaction between M / P -GluC16, L/D-GluC16, and a model protein (bovine serum albumin, BSA) was investigated at the thermodynamic and spatial orientational levels. Combined with the experimental result of protein adsorption efficiency, a more favorable chirality-dependent binding of M / P -GluC16 to protein compared to L/D-GluC16 was confirmed. Furthermore, driven by the binding-induced conformational changes and subsequent functional disruptions of proteins, M / P -GluC16 exhibited a greater chirality-specific cancer cell inhibitory efficacy compared to L/D-GluC16, highlighting the more significant impact of supramolecular chirality on nano-protein/cell interactions than molecular chirality.
研究领域:
纳米技术
·
生物物理学
·
细胞生物学
·
计算生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）