PROCEEDINGS OF THE COMBUSTION INSTITUTE
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2024
·
IF 5.3
Yuwen Deng,Zaili Xiong,Jijun Guo,Bingzhi Liu,Meirong Zeng,Zhandong Wang,Zhongyue Zhou,Wenhao Yuan,Fei Qi
Elucidating the oxidation chemistry of polycyclic aromatic hydrocarbons (PAHs) aids in understanding the degradation reaction processes of PAHs, as well as their competitive roles in PAH growth. In this work, ozone-assisted oxidation of indene , the smallest prototype PAH molecule, was investigated in an atmospheric jet stirred reactor at 400–550 K. Ab initio quantum chemistry calculations were conducted to characterize the oxidation kinetics of indene and interpret the experimental observations. Fingerprint oxidation products including 2-(2-oxoethyl) benzoic acid, 2-(formylmethyl) benzaldehyde , 1,2-indanedione and 1-indanone were identified by synchrotron vacuum ultraviolet photoionization mass spectrometry . The initial C 9 H 8 O 3 adduct resulting from O 3 -addition to indene exhibits high instability and is primarily detected as 2-(2-oxoethyl)benzoic acid following ozonolysis reactions. Minor amounts of vinylhydroperoxide were also observed as isomeric products of the C 9 H 8 O 3 adduct. Theoretical calculations indicate that indene ozonolysis is highly structure-dependent, where the conformation of the C 9 H 8 O 3 adduct determines the configuration of the resulting Criegee intermediates (CI). The distinctive reaction pathways introduced by the bifunctionalized characteristics of indene-derived large CIs are emphasized in this study. syn -Configuration CI features more conversion pathways compared to anti -CI due to the interaction between CI functionality and the neighboring aldehyde group, among which the bicyclic ring-closure reaction yielding secondary ozonide is most favored. The dioxirane intermediates generated from anti -CIs can undergo the Crossed Acid-forming channel to yield the target acid products, which provides an alternative way for dioxirane conversion. Further theoretical analyses demonstrate that ozonolysis is not the exclusive mechanism for indene oxidation under O 3 -assisted conditions. Instead, it is accompanied by low-temperature reactions initiated by OH/O 2 , leading to key products such as 2-(formylmethyl) benzaldehyde and 1-indanone. The present work aims to unravel the elusive chemistry involved in the O 3 -initiated oxidation of indene, providing new insights into the distinctive kinetics introduced by large bifunctionalized CIs in the ozonolysis of structurally similar PAHs.
研究领域:
化学动力学
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环境科学
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量子化学
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DOI
高影响因子
Antioxidants
·
2021
·Vol. 10
·期 9
·1333
·
IF 6.313
Mengyuan Fang,Tingfeng Zou,Xiaoxiao Yang,Zhen Zhang,Peichang Cao,Jihong Han,Yajun Duan,Ban-Feng Ruan,Qing-Shan Li
Sepsis remains one of the most common life-threatening illnesses that is characterized by a systemic inflammatory response syndrome (SIRS) and usually arises following severe trauma and various septic infections. It is still in urgent need of new effective therapeutic agents, and chances are great that some candidates can be identified that can attenuate oxidative stress and inflammatory responses. Pterostilbene, which exerts attractive anti-oxidative and anti-inflammatory activities, is a homologue of natural polyphenolic derivative of resveratrol. Starting from it, we have made several rounds of rational optimizations. Firstly, based on the strategy of pharmacophore combination, indanone moiety was introduced onto the pterostilbene skeleton to generate a novel series of pterostilbene derivatives (PIF_1–PIF_16) which could possess both anti-oxidative and anti-inflammatory activities for sepsis treatment. Then, all target compounds were subjected to their structure–activity relationships (SAR) screening of anti-inflammatory activity in mouse mononuclear macrophage RAW264.7 cell line, and their cytotoxicities were determined after. Finally, an optimal compound,PIF_9, was identified. It decreased the mRNA levels of lipopolysaccharide (LPS)-induced interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), and cyclooxygenase 2 (COX2). We also found that the anti-inflammatory effects might be contributed by its suppression on the nuclear factor-κB (NF-κB) and MAPKs signaling pathway. Moreover,PIF_9also demonstrated potent anti-oxidative activity in RAW264.7 macrophages and the sepsis mouse model. Not surprisingly, with the benefits mentioned above, it ameliorated LPS-induced sepsis in C57BL/6J mice and reduced multi-organ toxicity. Taken together,PIF_9was identified as a potential sepsis solution, targeting inflammation and oxidative stress through modulating MAPKs/NF-κB.Keywords:antioxidants;anti-inflammatory agents;indanone;pterostilbene;sepsis
研究领域:
药理学
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传染病学
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分子生物学
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DOI
PubMed
高影响因子
Asian Journal of Organic Chemistry
·
2023
·Vol. 12
·期 5
·e202300015
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IF 2.7
Yu-Tong Duan,Zhong-Xia Wang
Graphical Transition-metal-free reaction of oxindoles with primary or secondary alcohols in the presence of LiO t Bu affords α-C-alkylated oxindoles. Transition-metal-free α-C-alkylation of oxindoles with alcohols was performed. The reaction requires the presence of LiO t Bu and proceeds under thermal conditions. The method exhibits a wide scope of substrates. Both primary and secondary aliphatic and aromatic alcohols can be employed as the alkylating reagents. Oxindole and various 1-alkyl- or 1-aryl-substituted oxindoles can be alkylated. The mechanistic studies show that the reaction may involve both free radical and aldol condensation/MPV processes.
研究领域:
有机化学
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合成化学
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产品关联
DOI
高影响因子
COMBUSTION AND FLAME
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2024
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IF 5.8
Yuwen Deng,Zaili Xiong,Jijun Guo,Chen Huang,Long Zhao,Meirong Zeng,Zhongyue Zhou,Wenhao Yuan,Fei Qi
Fundamental knowledge about the production and oxidation chemistry of polycyclic aromatic hydrocarbons (PAHs) is essential for developing predictive soot models. In contrast to the significant progress in understanding the formation/growth kinetics of PAHs, the detailed oxidation kinetics of PAHs remains to be fully established. This study investigates the oxidation kinetics of indene, the simplest PAH, as a foundational step for examining larger PAHs. Experiments were conducted in a flow reactor at temperatures from 850 to 1350 K, under a pressure of 0.04 atm and an equivalence ratio of 0.5. Characteristic products were quantified using synchrotron vacuum ultraviolet photoionization mass spectrometry, including large resonance-stabilized PAH radicals with 3–4 aromatic rings. Results indicate that even under highly oxidative conditions, the mass growth pathways of indene remain competitive, leading to the production of various large PAHs. This phenomenon is unique to indene oxidation and has not been observed in other bicyclic aromatics. A detailed kinetic model was developed to interpret these findings, revealing that PAH formation is predominantly driven by the indenyl radical. This study further calculates the rate coefficients for the dominant mass growth pathway of indenyl, specifically its self-recombination reaction, to enhance predictions of indenyl and bi-indene. Notably, while spiran and bridging mechanisms are comparably important in cyclopentadienyl mass growth, the spiran mechanism is favored for indenyl, suggesting that the addition of a benzenoid ring significantly alters the reactivity of cyclopenta-like radicals. Comparative analysis with indene pyrolysis experiments reveals that under oxidative conditions, the indenyl radical preferentially decomposes into smaller species, e.g., cyclopentadienyl or cyclopentadiene, thereby enhancing the yields of PAHs that depend on C 5 species as precursors. In the early reaction stage (<1220 K), oxidation reactions promote indenyl formation, thus increasing the proportion of mass growth products. However, at higher temperatures (>1220 K), enhanced oxidation reactions of indenyl lead to its decomposition, outcompeting mass growth reactions and sharply reducing the proportion of mass growth products.
研究领域:
化学动力学
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燃烧科学
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DOI
高影响因子
Frontiers in Physiology
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2022
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IF 4.755
Hafeez Muhammad,Li Xiaowei,Ullah Farman,Zhang Zhijun,Zhang Jinming,Huang Jun,Fernández-Grandon G. Mandela,Khan Muhammad Musa,Siddiqui Junaid Ali,Chen Limin,Ren Xiao Yun,Zhou Shuxing,Lou Yonggen,Lu Yaobin
The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), is a pest of many important crops globally. Effective control is challenging, with the pest exhibiting resistance to different synthetic pesticides across various groups. However, the mechanisms employed by resistant insects for overexpression of relevant detoxification genes remain unclear. The activity of detoxification enzymes was investigated in this study. Additionally, using RNA interference (RNAi), a functional analysis was completed of two P450s genes in an indoxacarb resistant population of fall armyworms. Elevated resistance levels (resistance ratio = 31.37-fold) in indoxacarb-selected populations of FAW were observed after 14 generations. The qRT-PCR showed higher expression of two cytochrome P450 genes, CYP321A7 and CYP6AE43, in this selected population compared to the control population. RNAi was applied to knock down the P450 dsCYP321A7 and dsCYP6AE43 genes in the FAW larvae. Droplet feeding of the dsRNAs (CYP321A7 and CYP6AE43) via an artificial diet significantly increased mortality rates in the indoxacarb treated population. A shorter larval developmental time of FAW was detected in all dsRNAs-fed larvae. Correspondingly, larval mass was reduced by dsRNAs in indoxacarb resistant populations of fall armyworm. Larval feeding assays demonstrate that dsRNAs targeting, specifically of CYP321A7 and CYP6AE43 enzymes, could be a beneficial technique in the management of indoxacarb resistant populations. Further study on the potential use of dsRNA and its application should be conducted in efforts to counter the development of resistance in FAW against various insecticides in the field.
研究领域:
昆虫学
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分子生物学
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害虫管理
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DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2015
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IF 4.169
Qing Lv,Qing Zhang,Meiling Qi,Hua Bai,Qiang Ma,Xianshuang Meng,Ruonong Fu
Cyclotriveratrylene (CTV) is reported here for the first time as stationary phase for capillary gas chromatographic (GC) separations. CTV stationary phase showed weak polarity comparable to the conventional 5% phenyl polysiloxane stationary phase but exhibited different retention behaviours and higher resolution for some of the indicated analytes. Most importantly, CTV stationary phase exhibited preferential selectivity for halogenated compounds, positional and geometrical isomers. Effect of column temperature on retention and thermal stability of CTV column were also investigated. Moreover, CTV capillary column showed good repeatability in terms of run-to-run, day-to-day and column-to-column. The unique physicochemical features and efficient separation ability for analytes of close properties show the potential of CTV as a new-type stationary phase in GC as well as separation science.
研究领域:
分析化学
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色谱科学
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DOI
高影响因子
Nature Communications
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2024
·Vol. 15
·期 1
·1-12
·
IF 14.7
Zou Zhufan,Yu Zhenjie,Guan Weixiang,Liu Yanfang,Yao Yumin,Han Yang,Li Guangyi,Wang Aiqin,Cong Yu,Liang Xinmiao,Zhang Tao,Li Ning
Indan and tetralin are widely used as fuel additives and the intermediates in the manufacture of thermal-stable jet fuel, many chemicals, medicines, and shockproof agents for rubber industry. Herein, we disclose a two-step route to selectively produce 5-methyl-2,3-dihydro-1 H -indene (abbreviated as methylindan) and tetralin with xylose or the hemicelluloses from agricultural or forestry waste. Firstly, cyclopentanone (CPO) was selectively formed with ~60% carbon yield by the direct hydrogenolysis of xylose or hemicelluloses on a non-noble bimetallic Cu-La/SBA-15 catalyst. Subsequently, methylindan and tetralin were selectively produced with CPO via a cascade self-aldol condensation/rearrangement/aromatization reaction catalyzed by a commercial H-ZSM-5 zeolite. When we used cyclohexanone (another lignocellulosic cycloketone) in the second step, the main product switched to dimethyltetralin. This work gives insights into the selective production of bicyclic aromatics with lignocellulose.
研究领域:
化学工程
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可再生资源利用
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产品关联
DOI
PubMed
高影响因子
Polymers
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2020
·Vol. 12
·期 5
·1135
·
IF 3.426
Shiying Wang,Yi Zhang,Liupeng Yang,Qizhan Zhu,Qianli Ma,Ruifei Wang,Chaoqun Zhang,Zhixiang Zhang
Traditional pesticide formulations show poor utilization and environmental safety due to their low foliage adhesion and large auxiliaries. In this study, a novel and environment-friendly indoxacarb formulation was prepared to improve the pesticide’s utilization rate, target control characteristics and ecological security. Indoxacarb-loaded waterborne polyurethane–sodium alginate (PU/SA) nanoemulsions with film forming properties, alkaline responsive release, high effectiveness againstSpodoptera litura,and reduced acute contact toxicity for nontarget organisms were successfully prepared. The colloidal properties, swelling and release behaviors, leaf adhesion, degradation dynamics and bioactivity assay of the indoxacarb-loaded PU/SA nanoemulsions were determined. Results showed that the obtained indoxacarb-loaded microcapsule particulates were approximately 57 nm in diameter, electronegative −45.9 mV, and uniformly dispersed in the nanoemulsions. The dried latex films of PU/SA in the alkaline environment revealed better responsive swelling and release characteristics than those in acidic and neutral conditions. Compared with a commercial emulsifiable concentrate, the indoxacarb-loaded PU/SA nanoemulsions were useful for the targeted control ofS. litura, which have alkaline gut and showed reduced acute contact toxicity toHarmonia axyridia. Furthermore, the PU/SA formulation had better foliage adhesion and indicated the property of controlled-release and a persistent effect.Keywords:indoxacarb;anionic polyurethane;sodium alginate;nanoemulsions;bioactivity
研究领域:
农业科学
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环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
Advanced Electronic Materials
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2016
·Vol. 2
·期 11
·1600340
·
IF 0
Meng Wang,Zaiyu Wang,Wei Ma,Shan-Ci Chen,Qingdong Zheng
Despite the frequently renewed record high power conversion efficiencies (PCEs) in recent years, achieving single-junction polymer solar cells (PSCs) with both high PCE and large open circuit voltage ( V OC ) remains a challenge because there is a trade-off between high short circuit current density ( J SC ) and large V OC values. Here, the design and synthesis of a novel donor–acceptor (D–A) copolymer ( PIT2FBT ) based on an asymmetric-indenothiophene donor and a difluorinated benzo[c][1,2,5]thiadiazole acceptor is demonstrated. PIT2FBT exhibits a wide optical bandgap of 1.82 eV with a large ionization potential of 5.54 eV. Through systematic morphology control and device engineering, the best performance solar cell based on PIT2FBT shows a high PCE of 9.01% in combination with a large V OC of 1.0 V. To the best of our knowledge, the PCE is the highest for single-junction polymer fullerene solar cells with V OC s up to 1.0 V. At the same time, the influences of solvent additive on the active layer morphology together with the resulting device performance are investigated in-depth. These findings and detailed studies provide an important guidance to tune and optimize the morphology and photovoltaic properties of indenothiophene-based copolymers, which are promising candidates for short-wavelength absorbing materials in tandem PSCs.
研究领域:
材料科学
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能源科学
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产品关联
DOI
Biology-Basel
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2022
·Vol. 11
·期 12
·1718
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IF 5.168
Muhammad Hafeez,Xiaowei Li,Farman Ullah,Zhijun Zhang,Jinming Zhang,Jun Huang,Limin Chen,Junaid Ali Siddiqui,Xiaoyun Ren,Shuxing Zhou,Muhammad Imran,Mohammed A. Assiri,Myron P. Zalucki,Yonggen Lou,Yaobin Lu
Simple SummaryThe fall armyworm (FAW),Spodoptera frugiperda(J.E. Smith), is a voracious insect pest native to the Western Hemisphere, particularly in South America. The polyphagous fall armyworm feeds on more than 350 plants in such families, including Poaceae, Asteraceae, and Fabaceae. Transgenic plants that expressBacillus thuringiensisproteins (Bt plants) and synthetic insecticides are the main tactics to controlSpodoptera frugiperda, although widespread usage of synthetic chemicals has resulted in the emergence of resistance. We assessed cross-resistance, resistance mechanism, and fitness costs based on the life history traits ofSpodoptera frugiperda. Results indicated that after 24 generations of selection, the resistance to indoxacarb was increased by 472.67-fold as compared to the Ind-UNSEL. Significantly longer developmental time of larvae extended pupal duration, shorter adult longevity, and lower fecundity were observed in Ind-SEL as compared with the Ind-UNSEL population. Butoxide synergist increased susceptibility to indoxacarb, indicating that P450 enzymes may be involved in indoxacarb resistance. Therefore, it is crucial that we comprehend how insecticides work and how resistance develops in order to develop techniques for managing resistance. These data are valuable to understand the indoxacarb resistance mechanism and provides vital information for scientific-based guidance of pest management decisions.AbstractThe fall armyworm,Spodoptera frugiperda(J.E. Smith), is a voracious insect pest that is difficult to control due to resistance to insecticides and Bt proteins. We assessed cross-resistance, resistance mechanism, and fitness costs based on the life history traits ofS. frugiperda. We established anS. frugiperdastrain selected for resistance to indoxacarb (Ind-SEL) from a field-collected population and an unselected strain, Ind-UNSEL. Results indicated that after 24 generations of selection, the resistance to indoxacarb was increased by 472.67-fold as compared to the Ind-UNSEL. There was high cross-resistance to deltamethrin (31.23-fold) with very low or negligible cross-resistance to chlorantraniliprole, emamectin benzoate, and/or methoxyfenozide in the Ind-SEL population. Butoxide synergist increased susceptibility to indoxacarb, indicating that P450 enzymes may be involved in indoxacarb resistance. Significantly longer developmental time of larvae extended pupal duration, shorter adult longevity, and lower fecundity were observed in Ind-SEL as compared with the Ind-UNSEL population. The Net reproductive rate (R0) was the only growth parameter that differs between crosses of Ind-SEL♂ × Ind-UNSEL♀ (176 ± 46) and Ind-SEL♀ × Ind-UNSEL♂ (328 ± 57). On the other hand, all population growth parameters differ between Ind-SEL and Ind-UNSEL strains. Our work contributes to the growing body of research that demonstrates the importance of strain genetics in fitness cost experiments and helps resistance management programs make decisions.Keywords:Spodoptera frugiperda;indoxacarb selection;cross-resistance;inheritance of resistance;fitness cost
研究领域:
昆虫学
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害虫管理
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分子生物学
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产品关联
DOI
PubMed
高影响因子
ORGANIC & BIOMOLECULAR CHEMISTRY
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2014
·Vol. 13
·期 2
·601-611
·
IF 3.487
Xiong-Li Liu,Bo-Wen Pan,Wen-Hui Zhang,Chao Yang,Jun Yang,Yang Shi,Ting-Ting Feng,Ying Zhou,Wei-Cheng Yuan
A highly efficient and environmentally benign method for the synthesis of oxindoles featuring two contiguous quaternary carbon centers via an aldol reaction starting from various 3-substituted oxindoles has been established. A wide variety of such featured multi-substituted 1,3-indandione ring-fused 3-oxindole scaffolds were obtained smoothly in good yields (up to 98%) employing the most green of solvents, namely water, as reaction medium. Furthermore, their biological activity has been preliminarily demonstrated by in vitro evaluation against human prostate cancer cells PC-3, human lung cancer cells A549 and human leukemia cells K562 by MTT-based assays, using the commercially available standard drug, cisplatin, as a positive control. Gratifyingly, compounds 3s, 3u, 3y and 3c′ exhibited the best levels of in vitro inhibitory activity against human leukemia cells K562, which were almost 2.0, 2.8, 2.5 and 2.2 times, respectively, the activity of the positive control, cisplatin. Compound 3y had 2.7 times the activity of the positive control, cisplatin, against PC-3 cancer cells, and 3s, 3u and 3c′ showed levels of in vitro inhibitory activity against PC-3 cancer cells that were comparable to that of cisplatin. Compounds 3s, 3u and 3y had good inhibitory ability against human lung cancer cells A549. The results indicated that 1,3-indandione ring-fused 3-oxindole analogs may be useful leads for further biological screenings.
研究领域:
有机化学
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药物化学
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肿瘤学
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产品关联
DOI
PubMed
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Shaowen Pei,Xiuping Ju,Jinsheng Zhao,Hongmei Du
Two random copolymers, poly (benzotriazole-indacenodithiophene-benzothiadiazole) (PBTIDBD) and poly (benzotriazole-benzodithiophene-benzothiadiazole) (PBTBDBD) were synthesized and characterized by electrochemistry, spectroelectrochemistry, electrochromic switching, colorimetry and thermal gravimetric analysis. For PBTIDBD, the color of film changed from rosybrown in neutral state to transparent lightgrey in oxidized state. The band gap calculated according to the spectroelectrochemistry data is 1.86 eV, and the response time, optical contrast, coloration efficiency at 1560 nm are 1.04 s, 62.1%, 276.29 cm 2 ∙C -1 , respectively. And, for PBTBDBD, its color changes from rosybrown to transparent grey as it was fully oxidized. The band gap is 1.68 eV, and the response time, optical contrast, coloration efficiency at 1560 nm are 2.68 s, 62.4%, 193.31 cm 2 ∙C -1 , respectively. Both copolymers are stable at a high temperature, and the decomposition temperature of PBTIDBD and PBTBDBD are 463 °C and 326 °C. Both copolymers can be good candidates for electrochromic application.
研究领域:
材料科学
·
电化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）