FUEL
·
2022
·
IF 8.035
Xiaojun Dai,Yan Cheng,Meng Si,Qiang Wei,Dongdong Chen,Wenbin Huang,Yasong Zhou
A series of SAPO-11 molecular sieves were synthesized in the concentrated gel system by reducing the water content in the synthesis system. With SAPO-11 molecular sieves as supports, NiW-supported catalysts were prepared for the hydroisomerization of n-hexadecane. SAPO-11 molecular sieves and catalysts were characterized by XRD, SEM, N 2 adsorption–desorption, NH 3 -TPD, Py-IR, HRTEM and XPS. The results showed that reducing the water content in the synthesis system could increase the mesoporous volume of SAPO-11 molecular sieve and improve the acidity of SAPO-11. For the corresponding catalysts, using SAPO-11 synthesized in concentrated gel system as the support weakened the interaction between the active phase and the support, and increased the dispersion and stacking number of the active phase, which effectively improved the catalytic performance of the catalyst. The yield of i-hexadecane of the catalyst NiW/45W-SA corresponding to SAPO-11 synthesized in conventional water content system was 28.14%, while that of the catalyst NiW/5W-SA corresponding to SAPO-11 synthesized in concentrated gel system was 52.24%. According to the distribution of isomers, it is inferred that hydroisomerization of n-hexadecane over NiW/SAPO-11 follows the pore-mouth mechanism.
研究领域:
催化
·
材料科学
·
化学工程
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2026
·
IF 12.5
Wei Feng,Xiaodong Chen,Jin Bai,Mo Zheng,Jinjun Guo,Congbin Jiang,Xianxian Zhang,Zongqing Bai,Wen Li
Integrating ReaxFF MD with TGA and in-situ Py-TOF-MS reveals synergistic mechanisms in co-pyrolysis of coal with HDPE, PP, and PS. • PP promotes C 5 -C 6 high-calorific gases, while PS enhances aromatics by cross-linking pathways. • PP promotes C C and C H cleavage while PS inhibits C O breaking and weakly promotes C H cleavage. • Coal/HDPE and coal/PP co-pyrolysis drive PAHs formation via Diels-Alder, alkylation, and aromatization reactions. • The polymer type critically determines the nature of the dominant reactive intermediates. Co -pyrolysis of low-rank coal and waste polymers offers a promising approach for plastic valorization while enhancing coal utilization and oil quality. In this work, the polymer types on the synergistic mechanism governing the co -pyrolysis of Zhundong low-rank coal and three typical polymers of HDPE, PP and PS were systematically investigated by integrating ReaxFF MD simulation with experiments of TG and in-situ Py-TOF-MS. It is observed that the temperatures of maximum weight loss ( T max ) follow the order of HDPE > PP > PS, consistently reproduced across three methods. PP addition promotes C 5 -C 6 high-caloric-value gases via long-chain cleavage while inhibiting the MAHs production. In contrast, PS facilitates phenolic hydroxyl removal from coal, promoting aromatic products. PS preferentially enhances light tar yield from 17.81% to 22.14%, whereas HDPE suppresses heavy tar yields from 39.90% to 35.56%. The ReaxFF MD simulation results further demonstrate the underlying molecular-scale mechanisms that are hardly accessible by experiments. HDPE and PP inhibit C O bond formation while promoting C H bond breaking during the co-pyrolysis. PP exhibits the strongest promotion of C-C/ C H cleavage, whereas PS shows the weakest effect on C H dissociation. During coal/HDPE and coal/PP co-pyrolysis, the formation of PAHs is promoted through Diels-Alder, alkylation and aromatization reactions. For coal/PS, the phenyl-alkyl radicals from PS combine with light tar, heavy tar, and char intermediates from coal to form cross-linked intermediates, facilitating cleavage of α -C ar -C al , β -C al -C al , and C ar -O bonds toward aromatics. The integrated strategy provides a comprehensive perspective for understanding co-pyrolysis mechanisms in other solid fuels and waste treatments. Download: Download high-res image (87KB) Download: Download full-size image
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DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2022
·
IF 11.357
Qingcun Li,Yujian Lai,Peng Li,Xing Liu,Ziwei Yao,Jingfu Liu,Sujuan Yu
Although nanoplastics (NPs) are recognized as emerging anthropogenic particulate pollutants, the occurrence of NPs in the environment is rarely reported, partly due to the lack of sensitive methods for the concentration and detection of NPs. Herein, we present an efficient method for enriching NPs of different compositions and various sizes. Alkylated ferroferric oxide (Fe3O4) particles were prepared as adsorbents for highly efficient capture of NPs in environmental waters, and the formed large Fe3O4–NP agglomerates were separated by membrane filtration. Detection limits of 0.02–0.03 μg/L were obtained for polystyrene (PS) and poly(methyl methacrylate) (PMMA) NPs by detection with pyrolysis–gas chromatography–mass spectrometry (Py-GC/MS). When analyzing real water samples from different sources, it is remarkable that PS NPs were detected in 11 out of 15 samples with concentrations ranging from <0.07 to 0.73 μg/L, while PMMA were not detected. The wide detection of PS NPs in our study confirms the previous speculation that NPs may be ubiquitous in the environmental waters. The accurate quantification of PS NPs in environmental waters make it possible to monitor the pollution status of NPs in aquatic systems and evaluate their potential risks.
研究领域:
环境科学
·
分析化学
·
污染研究
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产品关联
DOI
PubMed
高影响因子
Polymers
·
2024
·Vol. 16
·期 10
·1309
·
IF 4.7
Lvchao Qiu,Yutong Zhou,Zhoufeng Zhao,Qi Wang,Lijun Chu,Shipeng Wen
Self-healing polydimethylsiloxane (PDMS) has garnered significant attention due to its potential applications across various fields. In this study, a functionalized modification of PDMS containing di-aminos was initially conducted using 2,6-pyridinedicarbonyl chloride to synthesize pyridine-PDMS (Py-PDMS). Subsequently, rare earth metal europium ions (Eu3+) were incorporated into Py-PDMS. Due to the coordination interaction between Eu3+and organic ligands, a coordination cross-linking network was created within the Py-PDMS matrix, resulting in the fabrication of Eu3+-Py-PDMS elastomer. At a molar ratio of Eu3+to ligands of 1:1, the tensile strength of Eu3+-Py-PDMS reached 1.4 MPa, with a fracture elongation of 824%. Due to the dynamic reversibility of coordination bonds, Eu3+-Py-PDMS with a metal-to-ligand molar ratio of 1:2 exhibited varying self-healing efficiencies at different temperatures. Notably, after 4 h of repair at 60 °C, its self-healing efficiency reached nearly 100%. Furthermore, the gas barrier properties of Eu3+-Py-PDMS with a molar ratio of 1:1 was improved compared with that of Eu3+-Py-PDMS with a molar ratio of 1:1. This study provides an effective strategy for the design and fabrication of PDMS with high mechanical strength, high gas barrier properties, and exceptional self-healing efficiency.
研究领域:
材料科学
·
化学工程
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2023
·
IF 5.9
Donghua Li,Feng Shi,Meihua Fu,Yi Lu,Can Liu,Xu Lin,Defa Hou,Hao Sun,Cuiping Luo,Zhifeng Zheng,Yunwu Zheng
To unveil the nitrogen migration and conversion characteristics, catalytic copyrolysis of biomass pseudo components and polyamide (PA) with different blend ratios (1:0, 5:1, 3:1, 1:1, 1:3, 1:5, 0:1) under an ammonia atmosphere was proposed to boost the yield of N-containing compounds (NCCs) and N-rich biochar. The evolution and distribution of NCCs in liquid, gas and biochar were systematically investigated with a combination of TG-MS, Py-GC/MS and EPR. Synergistic effects and possible reaction pathways were also evaluated. Experimental results showed that PA could obviously boost biomass conversion due to increasing the chance of secondary cleavage, and the comprehensive synergistic effect of biomass-derived H* radicals, acid sites of the catalyst and cracking reactions (-C-N and C-C bonds) that reduced the reaction energy barrier and enhanced the NH 3 and HCN yields. NH 3 comes from the amino acids that are released from the amino acid pyrolysis and hydrolysis of HCN on the surface of char, while HCN is from the secondary cracking of primary pyrolysis products. Adding biomass increased CO 2 , CO, CH 4 , C-O and C O emissions from co-pyrolysis. Additionally, significant synergetic effects were observed when Biomass/PA= 3:1, which improved the NCCs and pyridine yields by 78.58% and 48.23%, respectively, under the HZSM-5 catalyst. A lower proportion of PA addition facilitated the Maillard reaction and amide bond cleavage to enhance the NCCs content and suppressed π-conjugated ring structure compound evolution and coke-derived O-containing compound polymerization, while a higher content of PA was favorable for amine and diaza heterocycle compound formation. Moreover, the addition of PA reduced the HHV and N content in biochar, resulting in lower pyrrole-N content and graphitization degree due to secondary cross-polymerization reaction of reaction volatiles, but it enhanced the polarity due to higher oxygen content (14.98%).
研究领域:
能源与燃料
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2023
·
IF 5.3
Xiaojun Dai,Yan Cheng,Tingting Liu,Lingjuan Mao,Qiang Wei,Yasong Zhou
SAPO-11 molecular sieves with different crystal sizes and particle sizes, especially nanosized small-crystal SAPO-11 molecular sieves, were successfully synthesized, and the corresponding NiWS-supported catalysts were prepared for the hydroisomerization of n-hexadecane. XRD, SEM, N2 adsorption–desorption, Py-IR, and HRTEM were used to analyze the effects of crystal size and particle size of the supports on their physicochemical properties, active phase properties, and catalytic performance of the catalysts. Through reaction evaluation and analysis of isomeric products, the effects of the size change of the support on the hydroisomerization performance of the catalyst and the hydroisomerization depth of n-hexadecane were determined. Through comprehensive analysis of the cracking products, it was determined that secondary cracking occurred when the conversion of n-hexadecane on the NiW/SAPO-11-S catalyst reached about 42.7%, and the secondary isomerization occurred when the conversion of n-hexadecane reached about 80%. The hydroisomerization reaction network of n-hexadecane over the NiWS/SAPO-11 catalyst was studied emphatically, and it was found for the first time that the secondary cracking of n-hexadecane during hydroisomerization followed the C3-β-scission mechanism.
研究领域:
化学工程
·
催化
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2023
·Vol. 148
·期 10
·4211-4221
·
IF 4.4
Dai Shuming,Song Ping,Jiao Ziyue,Cheng Yi,Shang Jingzhao,Leng Xuefei,Wei Zhiyong,Li Yang
A series of bisphenol A-based polyarylates was synthesized by using 2,2-bis (4-hydroxyphenyl) propane (BPA), terephthaloyl dichloride (TPC), and isophthaloyl dichloride (IPC) as raw materials and p-tert-butylphenol as a capping agent through interfacial polymerization to investigate the effect of end group structure on polymer properties. And the polymer films could be obtained by solvent casting method. The successful introduction of p-tert-butylphenol into the backbone adjusted molecular masses and achieved a regulable improvement of the polymer’s thermal properties. The thermal mass loss 5% temperature of the polymers raised above 470 °C, which indicated the thermal properties were broadly in line with that of the commercial product U-100. Besides, the addition of capping agent also improved the light transmission of the polymers and the transmittance reached above 83% at a wavelength of 450 nm. In addition, the thermal degradation mechanism of polyarylate and U-100 was investigated by simultaneous thermal analysis (STA)-IR and Py/GC–MS. It was discovered that PAR decomposed thermally at their end groups and ester groups first, followed by the breakage of their carbon–carbon bonds, which coincided with U-100’s thermal degradation mechanism. The thermal degradation mechanism of bisphenol A-based polyarylates was proposed. Graphical abstract
研究领域:
高分子科学
·
材料科学
·
热分析
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2019
·
IF 3.47
Zhi Zheng,Jun Wang,Yi Wei,Xuejun Liu,Fengwen Yu,Jianbing Ji
La-Fe modified Si-MCM-41 (La-Fe/Si-MCM-41) catalysts were prepared by the wet impregnation method and used in catalytic cracking of soybean oil (CCS) for biofuel production. The catalysts were characterized by BET, XRD, XPS, Py-FTIR and CO 2 -TPD. The results showed that the aromatics content increased with the increase in B/L value, while the content of oxygenated compounds decreased, indicating that Brönsted acid sites were the major active sites for deoxygenation and aromatization reactions. Compared with Si-MCM-41, the Brönsted acidity of LFM-6 sharply decreased from 22.49 to 5.86 μmol g −1 . Accordingly, the aromatics content was reduced from 37.51 wt.% to 14.52 wt.% which was lower than the limitation (15 wt.%) according to the global environmental legislation. However, for the LFM-6 catalyst, the excessive loss of Brönsted acid sites and sharp decrease in BET surface area and pore volume led to the decrease in deoxygenation. As a result, the fatty acids content increased from 2.71 wt.% to 16.67 wt.% and the acid value reached 35.20 mgKOH g −1 . When the La-Fe loading increased to 15 wt.%, part of fatty acids were converted into ketones by the active sites on Fe 2 O 3 /La 2 O 3 and strong Lewis acid sites on catalysts. Besides, the new weak Lewis acid and basic sites on Fe 2 O 3 /La 2 O 3 exhibited the synergistic effect on promoting the generation of alkenes. The CaO/LFM-6 composite catalysts prepared by the mechanical mixing of LFM-6 and CaO were used in CCS to reduce the acid value of biofuel. LFM-6-C-3 was proved to be an effective catalyst for CCS to produce biofuel with low aromatics (12.31 wt.%) and fatty acids (2.76 wt.%) content.
研究领域:
催化
·
生物燃料
·
化学工程
·
环境科学
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产品关联
DOI
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 56
·35093-35098
·
IF 3.361
Jing Lu,Liang Ji,Yanyan Yu
As one type of reactive oxygen species (ROS), hydrogen peroxide (H2O2) plays a key role in regulating a variety of cellular functions. Herein, a fluorescent probe N-Py-BO was well designed and synthesized and its ability for detecting H2O2 by fluorescence intensity was evaluated. In the design, the arylboronate ester group was acted as a reaction site for H2O2. Upon reaction with H2O2 under physiological conditions, the boronate moiety in the probe was oxidized, followed by detachment from the probe and as a result, a “turn-on” fluorescence response for H2O2 was acquired. Due to the D–A structure formation between N,N′-dimethylaminobenzene and the –CN group and the linkage by thiophene and CC bonds to increase the conjugate length, this probe showed a remarkable red shift of emission wavelength (650 nm) as well as a large Stokes shift (214 nm). An excellent linear relation with concentrations of H2O2 ranging from 2.0 to 200 μM and a good selectivity over other biological species were obtained. Importantly, taking advantage of the low toxicity and good biocompatibility, the developed probe was successfully applied to monitoring and imaging H2O2 and its level fluctuation in living cells, which provided a powerful tool for evaluation of cellular oxidative stress and understanding the pathophysiological process of H2O2-related diseases.
研究领域:
化学
·
生物化学
·
细胞生物学
·
分析化学
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产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2025
·
IF 9.8
Xiao-Juan Wang,Kai-ting Liu,Chuan-Wan Wei,Shu-Qin Gao,Ying-Wu Lin
A metallohydrogel designated as 2-PY-Fe was synthesized via a straightforward method, exhibiting both peroxidase-like and oxidase-like activities. On one hand, based on its peroxidase-like activity, 2-PY-Fe can serve as a catalyst for the degradation of various dyes. On the other hand, 2-PY-Fe metallohydrogel was used as an oxidase-like nanozyme to catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) to oxTMB. The addition of nitrite can trigger the diazotization of oxTMB, resulting in a decrease in the absorption peak at 654 nm and the emergence of a new signal peak at 446 nm resulting from the diazotization of oxTMB. Simultaneously, the existence of nitrite induces the decrease of the electro-oxidation signal of TMB and presents a new electrochemical signal from nitrite itself. A ratiometric colorimetric/electrochemical method and a smartphone-assisted detection method were established, combining the oxidase-mimicking catalysis and diazotization reaction. Additionally, this developed method was applied to monitor nitrite in real samples.
研究领域:
材料科学
·
环境科学
·
分析化学
·
纳米技术
·
酶模拟
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DYES AND PIGMENTS
·
2019
·
IF 4.018
Xiangqian Li,Jiapei Gu,Zhan Zhou,Wanqiang Liu,Jinwei Gao,Qianming Wang
The versatility of the organic fluorophores enables us to track its emission curves and sharp luminescence changes under controllable conditions. A tetraphenylethylene-based fluorescent probe (1-methyl-4-(4-(1,2,2-triphenylvinyl)styryl)pyridin-1-ium iodide, abbreviated as TPE-py-I ) has been synthesized and yields efficient red emission in organic phase (DMSO). The incorporation of ClO − in its DMSO solution triggers efficient “on-off” quenching effect due to ions exchange from iodide to hypochlorite. The inactivation of the original red luminescence can be also realized by the addition of water and the typical aggregation-caused-quenching (ACQ) has been observed. Unexpectedly, such ACQ process will be suppressed and lead to an aggregation-induced-emission (AIE) effect, providing distinct fluorescent read-out from pale-red to bright yellow in the presence of hypochlorite. The limit of detection (LOD) has been calculated to be 0.25 μM via ratiometric operation with an excellent linear range from 1 μM to 50 μM. This non-invasive and in-situ detection of ClO − via AIE modes can be employed as an indicator for the evaluation of ions responses in real environments.
研究领域:
材料科学
·
分析化学
·
光学传感
✓ 已验证
产品关联
DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2024
·
IF 10.7
Sile Deng,Xiaoju Men,Muhua Hu,Xiao Liang,Yujuan Dai,Zhengkun Zhan,Zhongchao Huang,Haobin Chen,Zhuxin Dong
Reduced nicotinamide adenine dinucleotide (NADH) has a strong impact on physiological metabolism, and its concentration is related to metabolic and neurodegenerative diseases. A more reliable and accurate detection method for NADH quantitation is needed for early disease diagnosis and point-of-care testing. Aggregation-induced emission (AIE) materials are widely used to improve the sensitivity in analytes assays due to their anti-aggregation-caused quenching property. Here we developed TPA-BQD-Py AIE-dots transducers and evaluated its performance in NADH detection. The NADH concentration-dependent ratiometric sensing was based on electron transfer from TPA-BQD-Py AIE-dots to NADH with variable fluorescence intensity at 584 nm and 470 nm, resulting in high sensitivity (limit of detection at 110 nM), photostability, selectivity, and a rapid and reversible response. We further developed the application of TPA-BQD-Py AIE-dots transducers in in vivo NADH imaging using a smartphone and digital camera, respectively, demonstrating the potential for NADH point-of-care testing.
研究领域:
分析化学
·
生物医学工程
·
即时诊断
·
荧光传感
·
代谢组学
✓ 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）