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

Frontiers of Environmental Science & Engineering 2023年第3期17卷 49-61页

作者： Zhizhuo Liu Zhemin Shen Shouyan Xiang Yang sun jiahua cui Jinping Jia School of Environmental Science&Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The diverse and large-scale application of disinfectants posed potential health risks and caused ecological damage during the 2019-nCoV pandemic,thereby increasing the demands for the development of disinfectants based on natural products,with low health risks and low aquatic toxicity.In the present study,a few natural naphthoquinones and their derivatives bearing the 1,4-naphthoquinone skeleton were synthesized,and their antibacterial activity against selected bacterial strains was evaluated.In vitro antibacterial activities of the compounds were investigated against Escherichia coli and Staphylococcus aureus.Under the minimum inhibitory concentration(MIC)of≤0.125μmol/L for juglone(1a),5,8-dimethoxy-1,4-naphthoquinone(1f),and 7-methyl-5-acetoxy-1,4-naphthoquinone(3),a strong antibacterial activity against S.aureus was observed.All 1,4-naphthoquinone derivatives exhibited a strong antibacterial activity,with MIC values ranging between 15.625 and 500μmol/Land ECso values rangingbetween10.56 and248.42μmol/L.Most of the synthesized compounds exhibited strong antibacterial activities against S.aureus.Among these compounds,juglone(la)showed the strongest antibacterial activity.The results from mechanistic investigations indicated that juglone,a natural naphthoquinone,caused cell death by inducing reactive oxygen species production in bacterial cells,leading to DNA damage.In addition,juglone could reduce the self-repair ability of bacterial DNA by inhibiting RecA expression.In addition to having a potent antibacterial activity,juglone exhibited low cytotoxicity in cell-based investigations.In conclusion,juglone is a strong antibacterial agent with low toxicity,indicating that its application as a bactericidal agent may be associated with low health risks and aquatic toxicity.

关键词： 1,4-naphthoquinone derivatives Antibacterial Actionmechanism RecA

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机电伺服系统有限时间自适应反步控制方法研究

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机床与液压 2024年第9期52卷 87-93,185页

作者：邱佳华李泽周成龙崔国增郝万君苏州科技大学电子与信息工程学院江苏苏州215000

机电伺服系统存在未建模动态及不可避免的未知扰动,会严重影响系统的伺服性能。针对未知扰动下机电伺服系统惯性负载的角位移跟踪控制问题,考虑未建模动态对系统的影响,提出一种基于有限时间的模糊自适应指令滤波反步控制方法,能有效补... 详细信息

机电伺服系统存在未建模动态及不可避免的未知扰动,会严重影响系统的伺服性能。针对未知扰动下机电伺服系统惯性负载的角位移跟踪控制问题,考虑未建模动态对系统的影响,提出一种基于有限时间的模糊自适应指令滤波反步控制方法,能有效补偿系统中的未知扰动和未建模动态,具有良好的惯性负载角位移跟踪控制效果。针对系统中存在的未知外部扰动及未建模动态,结合滤波反步法和模糊控制理论,使用模糊逻辑系统逼近未知非线性动态同时构造自适应控制器。考虑到微分计算带来的计算爆炸问题,构建有限时间指令滤波器,降低了系统的计算复杂度,并通过设计滤波误差补偿机制,对滤波误差项进行补偿,保证滤波信号的逼近能力,提升系统跟踪控制性能。通过稳定性分析,证明所设计的控制器能够保证系统的跟踪误差在有限时间内收敛。最后通过仿真实验,验证了所提控制方法的有效性。

关键词：机电伺服系统有限时间未建模动态反步法模糊控制

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从铁矾渣侧吹熔炼—烟化法烟灰中回收锌镉及其净化除杂

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湿法冶金 2024年第2期43卷 121-128页

作者：张佳桦崔雅茹王国华王正民桂海平李邓李安鑫西安建筑科技大学冶金工程学院陕西西安710055 汉中锌业有限责任公司陕西汉中724204

研究了采用酸性浸出—硫化除杂法从铁矾渣侧吹熔炼—烟化法产出的烟灰中回收锌、镉,并选择性除去浸出液中的铜,产物用以制备镉掺杂硫化锌;在热力学分析基础上,探明了硫酸体系下锌浸出率影响因素及其浸出动力学;通过正交试验明确了各参... 详细信息

研究了采用酸性浸出—硫化除杂法从铁矾渣侧吹熔炼—烟化法产出的烟灰中回收锌、镉,并选择性除去浸出液中的铜,产物用以制备镉掺杂硫化锌;在热力学分析基础上,探明了硫酸体系下锌浸出率影响因素及其浸出动力学;通过正交试验明确了各参数对硫化钠选择性除杂的影响。结果表明:烟灰中锌主要以氧化锌形式存在,其浸出过程符合混合控制,表观活化能为73.70 kJ/mol;在最佳条件下,锌浸出率达98.99%。以Na_(2)S用量为理论添加量的3.2倍,控制体系pH=2.0,铜去除率可达95.97%,同时有效保留锌、镉,实现了铜与锌、镉的选择性分离。

关键词：烟灰硫酸浸出铜锌镉选择性分离

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煤系灰岩物化结构对瓦斯吸附特性的影响机制

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中国安全生产科学技术 2024年第5期20卷 170-176页

作者：郭晓阳刘一佳邓存宝徐家骅朱仔崔泽琛曹景夏宋留妮太原理工大学安全与应急管理工程学院山西太原030024 华阳新材料科技集团有限公司博士后工作站山西阳泉045000

为阐明分子结构和微观孔隙对煤系灰岩瓦斯吸附的影响机制,综合采用元素分析、化学检测、孔径分析、CT测试、瓦斯吸附实验和量子化学计算等方法表征灰岩物化特性,构建并优化分子结构,研究瓦斯吸附性能。研究结果表明:煤系灰岩含有较多C... 详细信息

为阐明分子结构和微观孔隙对煤系灰岩瓦斯吸附的影响机制,综合采用元素分析、化学检测、孔径分析、CT测试、瓦斯吸附实验和量子化学计算等方法表征灰岩物化特性,构建并优化分子结构,研究瓦斯吸附性能。研究结果表明:煤系灰岩含有较多C元素、有机官能团和有序芳香层,有机物石墨化程度高、晶体大、缺陷少,是其吸附瓦斯的化学基础;降低环境温度、增加吸附压力或减少含水率均能削弱灰岩吸附瓦斯的CH_4/CO_(2)竞争态势;灰岩含大量连通性好、结构复杂的吸附孔,孔隙系统更紧凑且各向异性更弱,是其吸附瓦斯的物理基础。研究结果可为煤岩体系瓦斯防治提供理论依据。

关键词：煤系灰岩瓦斯吸附特性微观孔隙量子化学分子结构

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Design, Synthesis and Anticancer Activity of Shikonin and Alkannin Derivatives with Different Substituents on the Naphthazarin Scaffold

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Chemical Research in Chinese Universities 2015年第3期31卷 394-400页

作者： ZHANG Xu cui jiahua ZHOU Wen LI Shaoshun School of Pharmacy Shanghai Jiao Tong University Shanghai 200240 P.R.China

Based on the asymmetric reduction of alkannin ketone derivative 4 by diisopinocampheylchloro- borane（DIP-C1）, a series of shikonin and alkannin derivatives was designed, synthesized and their anticancer activi- ties against various kinds of cell lines were evaluated. The in vitro biological experiments demonstrated that com- pound S-10, a 5,8-O-dimethyl-l,4-dioxime alkannin derivative, not only displayed excellent antiproliferative activity against cancer cells, but also exhibited 10w toxicity towards normal cells. It could induce HCT-116 cell apoptosis, but had no impact on the cell cycle. The underlying anticancer mechanism of S-10 is most likely different from other shikonin and alkannin derivatives.

关键词： Shikonin and alkannin oxime derivative Asymmetric reduction Anticancer Apoptosis Cell cycle

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Simulation of soil carbon changes due to land use change in urban areas in China

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Frontiers of Environmental Science & Engineering 2013年第2期7卷 255-266页

作者： cui HAO Jo SMITH jiahua ZHANG Weiqing MENG Hongyuan LI Laboratory for Remote Sensing and Climate Change Information Chinese Academy of Meteorological Sciences Beijing 100081 China School of Biological Sciences University of Aberdeen Aberdeen AB24 3UU UK Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100094 China College of Urban and Environmental Science Tianjin Normal University Tianjin 300387 China College of Environmental Science and Engineering Nankai University Tianjin 300071 China

Land use change can have a strong impact on soil carbon dynamics and carbon stocks in urban areas. Due to rapid urbanization, large areas of land have been paved, and other areas have undergone rapid land use change. Evaluation of the impact of urbanization on carbon dynamics and carbon stock （30 cm） has become an issue of urgent concern. The soil carbon dynamics, due to rapid land use change in Tianjin Binhai New Area of China, have been simulated in this paper using the RothC model. Because this area is saline, a modified version of RothC that includes a salt rate modifier provided more accurate simulations than the original model. The conversion to urban green land was not accurately simulated by either of the models because of the undefined changes in soil and plant conditions. According to the model, changes of arable to grassland resulted in a decline in soil carbon stocks, and changes of grassland to forest and grassland to arable resulted in increased soil carbon stocks in this area. Across the whole area simulated, the total carbon stocks in 2010 had decreased due to land use change by 6.5% from the 1979 value. By 2050, a further decrease of 21.9% is expected according to the 2050 plan for land use and the continuing losses from the soils due to previous land use changes.

关键词： land use change soil carbon RothC urbanarea

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Diatom-inspired multiscale mineralization of patterned protein–polysaccharide complex structures

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National Science Review 2021年第8期8卷 186-197页

作者： Ke Li Yingfeng Li Xinyu Wang Mengkui cui Bolin An jiahua Pu Jintao Liu Boyang Zhang Guijun Ma Chao Zhong School of Physical Science and Technology Shanghai Tech University Center for Materials Synthetic Biology Shenzhen Institute of Synthetic BiologyShenzhen Institutes of Advanced TechnologyChinese Academy of Sciences CAS Key Laboratory of Quantitative Engineering Biology Shenzhen Institute of Synthetic BiologyShenzhen Institutes of Advanced TechnologyChinese Academy of Sciences

Marine diatoms construct their hierarchically ordered, three-dimensional(3D) external structures called frustules through precise biomineralization processes. Recapitulating the remarkable architectures and functions of diatom frustules in artificial materials is a major challenge that has important technological implications for hierarchically ordered composites. Here, we report the construction of highly ordered,mineralized composites based on fabrication of complex self-supporting porous structures—made of genetically engineered amyloid fusion proteins and the natural polysaccharide chitin—and performing in situ multiscale protein-mediated mineralization with diverse inorganic materials, including SiO2, TiO2and Ga2O3. Subsequently, using sugar cubes as templates, we demonstrate that 3D fabricated porous structures can become colonized by engineered bacteria and can be functionalized with highly photoreactive minerals,thereby enabling co-localization of the photocatalytic units with a bacteria-based hydrogenase reaction for a successful semi-solid artificial photosynthesis system for hydrogen evolution. Our study thus highlights the power of coupling genetically engineered proteins and polysaccharides with biofabrication techniques to generate hierarchically organized mineralized porous structures inspired by nature.

关键词： biomimetic mineralization patterned porous structure genetic engineering amyloid protein artificial photosynthesis

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Investigation of the Insulator-Metai Transition Mechanism in trans-Polyacetylene

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Chinese Physics Letters 1992年第2期9卷 90-92页

作者： cui Yunlong LIN Senhao ZHANG jiahua Shanghai Institute of Nuclear Research Academia SinicaShanghai 201800

By using the Hamiltonian included in the static Su-Schrieffer-Heeger model and the Coulomb potential of solitons and ions,we investigated the insulator-metal transition mechanism in Na-doped trans-polyacetylene and gave the dependence of the Pauli susceptibility for 8.33%Na doping on the various widths and arrangements of the solitons.

关键词： solitons Transition trans

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Immobilization of functional nano-objects in living engineered bacterial biofilms for catalytic applications

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National Science Review 2019年第5期6卷 929-943页

作者： Xinyu Wang jiahua Pu Yi Liu Fang Ba Mengkui cui Ke Li Yu Xie Yan Nie Qixi Mi Tao Li Lingli Liu Manzhou Zhu Chao Zhong Division of Materials and Physical Biology School of Physical Science and TechnologyShanghai Tech University Shanghai Institute of Ceramics Chinese Academy of Sciences University of Chinese Academy of Sciences School of Life Science and Technology Shanghai Tech University Shanghai Institute for Advanced Immunochemical Studies (SIAIS) Shanghai Tech University College of Chemistry&Chemical Engineering Anhui University

Nanoscale objects feature very large surface-area-to-volume ratios and are now understood as powerful tools for catalysis, but their nature as nanomaterials brings challenges including toxicity and nanomaterial pollution.Immobilization is considered a feasible strategy for addressing these limitations.Here, as a proof-of-concept for the immobilization of nanoscale catalysts in the extracellular matrix of bacterial biofilms, we genetically engineered amyloid monomers of the Escherichia coli curli nanofiber system that are secreted and can self-assemble and anchor nano-objects in a spatially precise manner.We demonstrated three scalable, tunable and reusable catalysis systems: biofilm-anchored gold nanoparticles to reduce nitro aromatic compounds such as the pollutant p-nitrophenol, biofilm-anchored hybrid Cd0.9Zn0.1S quantum dots and gold nanoparticles to degrade organic dyes and biofilm-anchored CdSeS@ZnS quantum dots in a semi-artificial photosynthesis system for hydrogen production.Our work demonstrates how the ability of biofilms to grow in scalable and complex spatial arrangements can be exploited for catalytic applications and clearly illustrates the design utility of segregating high-energy nano-objects from injury-prone cellular components by engineering anchoring points in an extracellular matrix.

关键词： nanoscale catalyst immobilization semi-artificial photosynthesis living catalysis bio-inorganic hybrid system hydrogen production

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一类数列问题的探究

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河北理科教学研究 2022年第2期 21-22页

作者：崔镓桦河北省衡水市衡水中学 053000

数列是近代数学中的重要内容,利用线性空间的基,可以求出一类数列的通项公式,此方法突破了传统的求解思路,可以为我们解决此类数列问题提供一个通用模型.

关键词：数列通项公式集合

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