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期刊论文 20

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2023 5

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颤振导数 2

3-酰基硫代四酸 1

五唑 1

分子对接 1

动力特性 1

合成 1

合理体系 1

定量构效关系 1

抖振响应 1

抗菌活性 1

杀真菌剂 1

杀线虫活性 1

杀菌活性 1

湍流效应 1

炸药 1

系统识别 1

苏通大桥斜拉桥 1

雷诺数效应 1

高氮化合物 1

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Discovery of cryptolepine derivatives as novel promising agents against phytopathogenic bacteria

《化学科学与工程前沿(英文)》 2023年 第17卷 第2期   页码 156-166 doi: 10.1007/s11705-022-2196-5

摘要: To ensure the production of food crops, a series of cryptolepine derivatives were synthesised, after which their antibacterial activities and mechanism of action against three plant pathogens were investigated. Our bioassay results indicated that most of the target compounds displayed potent inhibitory effects against Xanthomonas oryzae (X. oryzae) and Xanthomonas axonopodis pv. citri (X. axonopodis pv. c.). Remarkably, compound 9 exhibited the best in vitro antibacterial activity against X. oryzae, with a minimum inhibitory concentration (MIC) value of 0.78 μg·mL–1. Compound 2 exhibited the best in vitro antibacterial activity against X. axonopodis pv. c., with an MIC value of 0.39 μg·mL–1. These activities were superior to those of copper quinolate (MIC = 6.25, 25 μg·mL–1) and thiodiazole copper (MIC = 100, 200 μg·mL–1) against X. oryzae and X. axonopodis pv. c. In vivo experiments demonstrated the promising applicability of compound 9 for the control of rice bacterial infections. Furthermore, compound 9 was selected as a candidate to conduct preliminary analyses of the antibacterial mechanisms of cryptolepine derivatives. Scanning electron microscopy and transmission electron microscopy observations, extracellular polysaccharide production, biofilm formation, transcriptomic, quantitative reverse transcription-polymerase chain reaction analyses, and molecular docking assays were performed. Collectively, our findings demonstrated that compound 9 might act via multifarious mechanisms to down-regulate virulence factors and cause cell death.

关键词: cryptolepine derivatives     phytopathogenic bacteria     antibacterial activity     mechanism of action    

Evaluation of 1,4-naphthoquinone derivatives as antibacterial agents: activity and mechanistic studies

《环境科学与工程前沿(英文)》 2023年 第17卷 第3期 doi: 10.1007/s11783-023-1631-2

摘要:

● All 1,4-naphthoquinone hybrids exhibited significant antimicrobial activity.

关键词: 1     4-naphthoquinone derivatives     Antibacterial     Action mechanism     RecA    

Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4

《化学科学与工程前沿(英文)》 2022年 第16卷 第7期   页码 1090-1100 doi: 10.1007/s11705-021-2091-5

摘要: Twenty six novel pyrimidin-4-amine derivatives containing the 1,2,4-oxadiazole motif were synthesized. Their chemical structures were confirmed by 1H nuclear magnetic resonance (NMR), 13C NMR, and high-resolution mass spectrography. The insecticidal activity results indicated that some of them possessed excellent insecticidal activity (100%) against Mythimna separate, especially for compounds 6d, 6f, 6o, 6w, 6y and 6z. These compounds exhibited no activity against the insects Aphis medicagini and Tetranychus cinnabarinus. The structure- insecticidal activity relationships are discussed. Density functional theory analysis can potentially be used to design more active compounds. These results provide useful insecticide design information for further optimization.

关键词: synthesis     pyrimidin-4-amine derivatives     1     2     4-oxadiazole     insecticidal activity     structure-activity relationship    

Discovery of novel ursolic acid derivatives as effective antimicrobial agents through a ROS-mediated

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 2101-2113 doi: 10.1007/s11705-023-2361-5

摘要: In response to the reduction of food production and economic losses caused by plant bacterial diseases, it is necessary to develop new, efficient, and green pesticides. Natural products are rich and sustainable source for the development of new pesticides due to their low toxicity, easy degradation, and eco-friendliness. In this study, we prepared three series of ursolic acid derivatives and assessed their antibacterial ability. Most target compounds exhibited outstanding antibacterial activities. Among them, the relative optimal EC50 values of Xanthomonas oryzae pv. oryzae and Xanthomonas axonopodis pv. citri were 2.23 (A17) and 1.39 (A16) μg·mL–1, respectively. The antimicrobial mechanism showed that compound A17 induced an excessive accumulation and production of reactive oxygen species in bacteria and damaged the cell membrane integrity to kill bacteria. More interestingly, the addition of low concentrations of exogenous hydrogen peroxide enhanced the antibacterial efficacy of compound A17 against Xanthomonas oryzae pv. oryzae. These entertaining results suggested that compound A17 induced an apparent apoptotic behavior in the tested bacteria. Overall, we developed the promising antimicrobial agents that destroyed the redox system of phytopathogenic bacteria, further demonstrating the unprecedented potential of ursolic acid for agricultural applications.

关键词: ursolic acid     antibacterial activities     reactive oxygen species     apoptosis    

Comparisons of bridges flutter derivatives and generalized ones

Fuyou XU , Zhe ZHANG , Cailiang HUANG , Airong CHEN ,

《结构与土木工程前沿(英文)》 2009年 第3卷 第3期   页码 272-278 doi: 10.1007/s11709-009-0042-1

摘要: The causes of the nonlinearity of self-excited aerodynamic force of bridge are interpreted from such two aspects as amplitude and wind velocity. The concept of “generalized flutter derivative” is proposed, and its physical meaning is illustrated. The graphs of the generalized flutter derivatives of plate and Sutong Bridge section model are plotted. The characteristics of all generalized flutter derivatives are compared and analyzed, and their superiorities are verified. The results indicate that the physical meaning of generalized flutter derivatives are more explicit compared to the traditional ones. It is more convenient to understand the nonlinearity properties of self-excited aerodynamic force of bridge according to the generalized flutter derivatives graphs with the wind velocity as the horizontal coordinate.

关键词: bridge     flutter derivative     generalized flutter derivative     self-excited aerodynamic force     Sutong Bridge    

Synthesis and ultraviolet/aggregation-induced emission investigation of novel tetraphenylvinyl hydrazone derivatives

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 2061-2073 doi: 10.1007/s11705-023-2366-0

摘要: Herein, three novel tetraphenylethylene hydrazone chemosensors TC12, SC16, and TC16 are prepared for the selective detection of F. Two NH and one C=N units are incorporated into the sensors for better colorimetric responses, whereas the tetraphenyl unit is in charge of the aggregation-induced emission effect. Among them, compounds SC16 and TC16 form stable gels with some organic solvents. All the tetrahydrofuran/H2O solutions of the three compounds exhibit aggregation-induced emission effect, whereby the fluorescence emission increases by varying degrees with the volume of poor solvent water. Moreover, good aggregation-induced emission effects are observed in the self-assembly of SC16 and TC16. As a sample chemosensor, TC12 in tetrahydrofuran responds to F selectively with high sensitivity, with the colorimetric and fluorometric detection limits of 8.25 × 10−7 mol·L–1 and 2.69 × 10−7 mol·L–1, respectively. The reversible gel-sol-gel phase transition and color changes indicate that both SC16-dimethyl sulfoxide and TC16-ethyl acetate gels specifically respond to F with good sensitivity. The detection results are well supported by ultraviolet-visible spectroscopy, fluorescent spectroscopy, and 1H nuclear magnetic resonance. More importantly, the driving forces of gelation are visually clarified through the single crystal X-ray analysis of compound TOMe.

关键词: organogelator     tetraphenylvinyldrazone     single crystal     aggregation-induced emission effect     ion sensing    

Effect of graphene and its derivatives on thermo-mechanical properties of phase change materials and

《能源前沿(英文)》 2022年 第16卷 第2期   页码 150-186 doi: 10.1007/s11708-021-0795-3

摘要: Phase change materials (PCMs) play a leading role in overcoming the growing need of advanced thermal management for the storage and release of thermal energy which is to be used for different solar applications. However, the effectiveness of PCMs is greatly affected by their poor thermal conductivity. Therefore, in the present review the progress made in deploying the graphene (Gr) in PCMs in the last decade for providing the solution to the aforementioned inadequacy is presented and discussed in detail. Gr and its derivatives ((Gr oxide (GO), Gr aerogel (GA) and Gr nanoplatelets (GNPs)) based PCMs can improve the thermal conductivity and shape stability, which may be attributed to the extra ordinary thermo-physical properties of Gr. Moreover, it is expected from this review that the advantages and disadvantages of using Gr nanoparticles provide a deep insight and help the researchers in finding out the exact basic properties and finally the applications of Gr can be enhanced.

关键词: phase change materials (PCMs)     graphene     thermal conductivity     characterization    

Magnetic KIT-6 nano-composite and its amino derivatives as convenient adsorbent for U(VI) sequestration

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 2037-2049 doi: 10.1007/s11705-023-2358-0

摘要: Although mesoporous silica with magnetically hybridized two-dimensional channel structures has been well studied in recent years, it remains a challenge to fabricate the counterpart with macroporous three-dimensional cubic structures since the highly acidic preparation conditions lead to dissolution of magnetic particles. Herein, we successfully prepared magnetic KIT-6 nano-composite and its amino derivatives by bearing acid-resistant iron oxide. The prepared materials exhibited excellent properties for U(VI) ions removal from aqueous solutions under various conditions. The experimental data show that the U(VI) adsorption features fast adsorption kinetics, high adsorption capacity and ideal selectivity toward U(VI). The adsorption process is of spontaneous and endothermic nature and ionic strength independence, and the adsorbents can be easily regenerated by acid treatment. Compared to pristine KIT-6, the introduction of magnetism does not reduce the efficiency of the material to remove U(VI) while exerting its role as a recovery adsorbent. The findings of this work further demonstrate the potential broad application prospects of magnetic hybrid mesoporous silica in radionuclide chelation.

关键词: magnetic nanoparticle     3D mesoporous silica     amino functionalization     adsorption of U(VI)     acid resistance    

Determination of aniline derivatives in water samples after preconcentration with oxidized multiwalled

Hideyuki KATSUMATA, Yuta ODA, Satoshi KANECO, Tohru SUZUKI, Kiyohisa OHTA

《化学科学与工程前沿(英文)》 2012年 第6卷 第3期   页码 270-275 doi: 10.1007/s11705-012-1298-x

摘要: A sensitive and selective preconcentration method using solid-phase extraction (SPE) disk made from oxidized multiwalled carbon nanotubes (OMWCNTs), has been developed for the determination of aniline derivatives, such as 2-nitroaniline (2-NA), 4-nitroaniline (4-NA), and 2,4-dichloroaniline (2,4-DCA) in water samples. Anilines were extracted onto OMWCNT disk and then determined by high performance liquid chromatography (HPLC) with UV detector. Several parameters on the recovery of the analytes were investigated. The experimental results showed that it was possible to obtain quantitative analysis when the solution pH was 8 using 200 mL of validation solution containing 2 μg of anilines and 10 mL of acetonitrile/ethanol (8/2, v/v) as an eluent. Relative standard deviations for five determinations were 7.5% (2-NA), 6.5% (4-NA) and 3.8% (2,4-DCA) under optimum conditions. The linear range of calibration curves were 0.5 ng·mL to 15 ng·mL for each analyte with good correlation coefficients. The detection limits (3S/N) of 2-NA, 4-NA and 2,4-DCA were 30 pg·mL , 31 pg·mL and 26 pg·mL , respectively. Our method was successfully applied to the determination of aniline compounds in river water sample with high precision and accuracy.

关键词: aniline determination     solid-phase extraction     oxidized multiwalled carbon nanotubes     water sample     HPLC-UV    

The synthesis of 6-(tert-butyl)-8-fluoro-2,3-dimethylquinoline carbonate derivatives and their antifungal

Long Cheng, Ruirui Zhang, Hongke Wu, Xinghai Liu, Tianming Xu

《化学科学与工程前沿(英文)》 2019年 第13卷 第2期   页码 369-376 doi: 10.1007/s11705-018-1734-7

摘要: A series of novel 6-( -butyl)-8-fluoro-2,3-dimethylquinoline carbonate derivatives were designed and synthesized. Bioassay results showed that some of them exhibited good activity against ( ). It was found that the compound (benzyl (6-( -butyl)-8-fluoro-2,3- dimethylquinolin-4-yl) carbonate) possessed good activity against whatever protective activity (10 mg·L ) or curative activity (25 mg·L ), which was better than that of control tebufloquin. In addition, the frontier molecular orbit results revealed that the compound held higher activity against when the total energy was low and the ClogP was high, which may provide useful information for further design novel fungicides.

关键词: quinoline     synthesis     antifungal activity     rice blast     SAR    

Design, synthesis, biological activity and density function theory study of pyrazole derivatives containing

Xiaoming Ding, Zhiwen Zhai, Luping Lv, Zhaohui Sun, Xinghai Liu

《化学科学与工程前沿(英文)》 2017年 第11卷 第3期   页码 379-386 doi: 10.1007/s11705-017-1634-2

摘要: A variety of pyrazole derivatives containing 1,3,4-thiadiazole moiety were synthesized under microwave irradiation, and their structures were confirmed by H NMR and HRMS. They were evaluated for herbicidal and antifungal activities, and the results indicated that two compounds with a phenyl group ( ) and 4- -butylphenyl group ( ) possess good herbicidal activity for dicotyledon and with the inhibition of 90% for root and 80%–90% for stalk at 100 ppm respectively. The structure-activity relationship of compounds and was also studied by density function theory method.

关键词: pyrazole     1     3     4-thiadiazole     antifungal activity     herbicidal activity     density function theory    

含能五唑阴离子及其衍生物的合成与性质研究进展 Review

Dominique R. Wozniak, Davin G. Piercey

《工程(英文)》 2020年 第6卷 第9期   页码 981-991 doi: 10.1016/j.eng.2020.05.019

摘要:

自2002年Christe等首次对五唑(cyclo-N5)进行质谱检测以来,这个唑类的最新成员就受到了越来越多的关注。由于不含碳和氢,五唑阴离子可以释放大量能量,同时分解为对环境友好的氮气。由于这些吸引人的特性,cyclo-N5和相关化合物对于高能密度材料(HEDM)研究的发展至关重要。本文旨在提供有关cyclo-N5所有研究的综合报告,重点是作为高能材料的五唑及其实验合成。本文主要包括以下内容:①cyclo-N5的历史意义;②cyclo-N5的前驱体;③以芳基五唑前驱体为重点的cyclo-N5合成路线;④影响cyclo-N5的稳定性的因素;⑤目前含能cyclo-N5化合物的高能性能;⑥未来有潜力的实验研究。本文全面总结了人们当前对cyclo-N5 的了解,旨在进一步了解这种阴离子作为下一代强大而环保的炸药的潜力。

关键词: 炸药     五唑     高氮化合物    

Laser ablation of block copolymers with hydrogen-bonded azobenzene derivatives

Jintang Huang, Youju Huang, Si Wu

《化学科学与工程前沿(英文)》 2018年 第12卷 第3期   页码 450-456 doi: 10.1007/s11705-018-1735-6

摘要:

Supramolecular assemblies (PS-b-P4VP(AzoR)) are fabricated by hydrogen-bonding azobenzene derivatives (AzoR) to poly(4-vinyl pyridine) blocks of polystyrene-block-poly(4-vinyl pyridine) (PS-b-P4VP). PS-b-P4VP(AzoR) forms phase separated nanostructures with a period of ~75–105 nm. A second length scale structure with a period of 2 µm is fabricated on phase separated PS-b-P4VP(AzoR) by laser interference ablation. Both the concentration and the substituent of AzoR in PS-b-P4VP(AzoR) affect the laser ablation process. The laser ablation threshold of PS-b-P4VP(AzoR) decreases as the concentration of AzoR increases. In PS-b-P4VP(AzoR) with different substituents (R= CN, H, and CH3), ablation thresholds follow the trend: PS-b-P4VP(AzoCN)<PS-b-P4VP(AzoCH3)<PS-b-P4VP(AzoH). This result indicates that the electron donor group (CH3) and the electron acceptor group (CN) can lower the ablation threshold of PS-b-P4VP(AzoR).

关键词: laser ablation     block copolymers     hydrogen-bond     azobenzene derivatives     supramolecular assembly    

Time-domain and frequency-domain approaches to identification of bridge flutter derivatives

Zhengqing CHEN

《结构与土木工程前沿(英文)》 2009年 第3卷 第2期   页码 173-179 doi: 10.1007/s11709-009-0034-1

摘要: Flutter derivatives are essential for flutter analysis of long-span bridges, and they are generally identified from the vibration testing data of a sectional model suspended in a wind tunnel. Making use of the forced vibration testing data of three sectional models, namely, a thin-plate model, a nearly streamlined model, and a bluff-body model, a comparative study was made to identify the flutter derivatives of each model by using a time-domain method and a frequency-domain method. It was shown that all the flutter derivatives of the thin-plate model identified with the frequency-domain method and time-domain method, respectively, agree very well. Moreover, some of the flutter derivatives of each of the other two models identified with the two methods deviate to some extent. More precisely, the frequency-domain method usually results in smooth curves of the flutter derivatives. The formulation of time-domain method makes the identification results of flutter derivatives relatively sensitive to the signal phase lag between vibration state vector and aerodynamic forces and also prone to be disturbed by noise and nonlinearity.

关键词: long-span bridges     wind-induced vibration     flutter derivatives     forced vibration test     time-domain method     frequency-domain method    

湍流效应对桁架式桥梁断面气动弹性性能影响的研究

Hoang Trong Lam, Hiroshi Katsuchi, Hitoshi Yamada

《工程(英文)》 2017年 第3卷 第6期   页码 845-853 doi: 10.1016/j.eng.2017.10.001

摘要:
本文介绍了在不同湍流条件下通过随机系统识别(SSI)方法提取颤振导数(FD)的过程。研究旨在通过对节段模型风洞试验来研究湍流对悬索式大跨度桥梁的影响。针对不同的湍流特性,对桁架式桥梁断面进行了几项风洞试验,包括降低湍流强度和湍流尺度。研究包括湍流对模型动态响应的影响。利用系统识别技术提取FD,对风洞试验中的瞬态响应和抖振响应进行了分析,同时讨论了该方法存在的困难。利用时域SSI 同时从一自由度(1DOF)和二自由度(2DOF)系统提取所有的FD。最后,讨论了不同情况下的结果并得出结论。

关键词: 颤振导数     系统识别     湍流效应     抖振响应    

标题 作者 时间 类型 操作

Discovery of cryptolepine derivatives as novel promising agents against phytopathogenic bacteria

期刊论文

Evaluation of 1,4-naphthoquinone derivatives as antibacterial agents: activity and mechanistic studies

期刊论文

Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4

期刊论文

Discovery of novel ursolic acid derivatives as effective antimicrobial agents through a ROS-mediated

期刊论文

Comparisons of bridges flutter derivatives and generalized ones

Fuyou XU , Zhe ZHANG , Cailiang HUANG , Airong CHEN ,

期刊论文

Synthesis and ultraviolet/aggregation-induced emission investigation of novel tetraphenylvinyl hydrazone derivatives

期刊论文

Effect of graphene and its derivatives on thermo-mechanical properties of phase change materials and

期刊论文

Magnetic KIT-6 nano-composite and its amino derivatives as convenient adsorbent for U(VI) sequestration

期刊论文

Determination of aniline derivatives in water samples after preconcentration with oxidized multiwalled

Hideyuki KATSUMATA, Yuta ODA, Satoshi KANECO, Tohru SUZUKI, Kiyohisa OHTA

期刊论文

The synthesis of 6-(tert-butyl)-8-fluoro-2,3-dimethylquinoline carbonate derivatives and their antifungal

Long Cheng, Ruirui Zhang, Hongke Wu, Xinghai Liu, Tianming Xu

期刊论文

Design, synthesis, biological activity and density function theory study of pyrazole derivatives containing

Xiaoming Ding, Zhiwen Zhai, Luping Lv, Zhaohui Sun, Xinghai Liu

期刊论文

含能五唑阴离子及其衍生物的合成与性质研究进展

Dominique R. Wozniak, Davin G. Piercey

期刊论文

Laser ablation of block copolymers with hydrogen-bonded azobenzene derivatives

Jintang Huang, Youju Huang, Si Wu

期刊论文

Time-domain and frequency-domain approaches to identification of bridge flutter derivatives

Zhengqing CHEN

期刊论文

湍流效应对桁架式桥梁断面气动弹性性能影响的研究

Hoang Trong Lam, Hiroshi Katsuchi, Hitoshi Yamada

期刊论文