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Computer Modeling in Engineering & Sciences 2024年第5期139卷 2175-2195页

作者： Jiawei shi jiye Zhang State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu610031China

Combining the detached eddy simulation(DES)method and Ffowcs Williams-Hawkings(FW-H)equation,the effect of bogie cavity end wall inclination on the flow field and aerodynamic noise in the bogie region is numerically ***,the simulation is conducted based on a simplified cavity-bogie model,including five cases with different inclination angles of the front and rear walls of the *** comparing and analyzing the flow field and acoustic results of the five cases,the influence of the regularity and mechanism of the bogie cavity end wall inclination on the flow field and the aerodynamic noise of the bogie region are ***,the noise reduction strategy determined by the results of the simplified cavity-bogie model is applied to a three-car marshaling train model to verify its effectiveness when applied to the real *** results reveal that the forward inclination of the cavity front wall enlarges the influence area of shear vortex structures formed at the leading edge of the cavity and intensifies the interaction between the vortex structures and the front wheelset,frontmotor,and front gearbox,resulting in the increase of the aerodynamic noise generated by the bogie *** backward inclination of the cavity rear wall is conducive to guiding the vortex structures flow out of the cavity and weakening the interaction between the shear vortex structures and the cavity rear wall,leading to the reduction of the aerodynamic noise generated by the bogie *** the rear end wall of the foremost bogie cavity of the head car is a feasible aerodynamic noise reduction measure for high-speed trains.

关键词： Bogie cavity flow aerodynamic noise end wall inclination

Phase transferring luminescent gold nanoclusters via single-stranded DNA

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Science China Chemistry 2022年第6期65卷 1212-1220页

作者： Yu Li Hui Lu Zhibei Qu Mingqiang Li Haoran Zheng Peilin Gu jiye shi Jiang Li Qian Li Lihua Wang Jing Chen Chunhai Fan Jianlei Shen Division of Physical Biology CAS Key Laboratory of Interfacial Physics and TechnologyShanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai201800China University of Chinese Academy of Sciences Beijing100049China School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules and National Center for Translational MedicineShanghai Jiao Tong UniversityShanghai200240China Shanghai Synchrotron Radiation Facility Zhangjiang LaboratoryShanghai Advanced Research InstituteChinese Academy of SciencesShanghai201210China Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai200127China

Atomically precise gold nanoclusters(Au NCs) are an emerging class of quantum-sized nanomaterials with discrete electronic energy levels, which has led to a range of attractive electronic and optical applications. Nevertheless, the lack of general methods to transfer Au NCs protected with hydrophobic ligands to an aqueous solution hampers their use in physiological settings. Here,we developed a single-stranded DNA-based approach that could transfer ~90% hydrophobic Au NCs into an aqueous *** experimentally and theoretically established that multivalent electrostatic and hydrophobic interactions between DNA strands and the hydrophobic ligand layer on Au NCs resulted in monodispersed DNA-coated Au NCs with high physical integrity in an aqueous solution. The fluorescence quantum yield of Au NCs was increased by ~13 fold, and surface-constrained DNA retained the specific recognition ability for biosensing. We further demonstrated the versatility of this phase-transfer approach, which thus holds great potential to advance biological and medical applications of Au NCs.

关键词： gold nanoclusters DNA monodispersed phase transfer biological application

Recognizing single phospholipid vesicle collisions on carbon fiber nanoelectrode

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Science China Chemistry 2017年第11期60卷 1474-1480页

作者： Yueyue Zhang Min Li Zhenhua Li Qian Li Ali Aldalbahi jiye shi Lihua Wang Chunhai Fan Xiaolei Zuo Division of Physical Biology Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Chemistry Department King Saud UniversityRiyadh 11451Saudi Arabia

We recognize the stochastic collisions of dopamine contained phospholipid vesicle on carbon fiber nanoelectrode, extending the observation of discrete collision events on nanoelectrode to biologically relevant analytes. To decrease noise interference to the technique, the dimensions of nanoelectrode was systematically investigated and optimized. Scanning electron microscopy(SEM) further supported the comparable sizes of nanoelectrode and vesicles(~100 nm in diameter). Vesicles collision and rupture on the surface of nanoelectrode led to the dopamine release from vesicles, which could be electrochemically oxidized to dopamine-o-quinone and detected via voltammetry. The comparable size of the nanoelectrode with vesicles and fast voltammetry allowed differentiation of single collision events from the current magnitudes and peak widths in the electrochemical collision experiments, which shows the efficacy of the method to characterize vesicle samples. This work provides a foundation upon which quantitative sensor technology might be built for the detection of dopamine contained vesicles with high spatial and temporal resolution.

关键词：碰撞事件碳纳米纤维脂囊泡扫描电子显微镜电化学氧化单层高空间分辨率磷

Deciphering active biocompatibility of iron oxide nanoparticles from their intrinsic antagonism

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Nano Research 2018年第5期11卷 2746-2755页

作者： Lu Wang Zejun Wang Xiaoming Li Yi Zhang Min Yin Jiang Li Haiyun Song jiye shi Daishun Ling Lihua Wang Nan Chen Chunhai Fan Division of Physical Biology and Bioimaging Center Shanghai Synchrotron Radiation Focility CAS Key Laboratory of Interracial Physics and Technology Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China School of Life Scienceand Technology Shanghai Tech University Shanghai 201210 China Key Laboratory of Food Safety Research Institute for Nutritional Sciences Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China UCB Pharma 208 Bath Road Slough SL1 3WE UK College of Pharmaceutical Sciences Zhejiang University Hangzhou 310058 China

Magnetite nanoparticles （Fe3O4 NPs） are a well proven biocompatible nanomaterial, which hold great promise in various biomedical applications. Interestingly, unlike conventional biocompatible materials （e.g., polyethylene glycol （PEG）） that are chemically and biologically inert in nature, Fe3O4 NPs are known to be catalytically active and exhibit prominent physiological effects. Herein, we report an ＂active＂, dynamic equilibrium mechanism for maintaining the cellular amenity of Fe3O4 NPs. We examined the effects of two types of iron oxide （magnetite and hematite） NPs in rat pheochromocytoma （PC12） cells and found that both induced stress responses. However, only Fe2O3 NPs caused significant programmed cell death; whereas Fe3O4 NPs are amenable to cells. We found that intrinsic catalase-like activity of Fe3O4 NPs antagonized the accumulation of toxic reactive oxygen species （ROS） induced by themselves, and thereby modulated the extent of cellular oxidative stress, autophagic activity, and programmed cell death. In line with this observation, we effectively reversed severe autophagy and cell death caused by Fe2O3 NPs via co-treatment with natural catalase. This study not only deciphers the distinct intrinsic antagonism of Fe3O4 NPs, but opens new routes to designing biocompatible theranostic nanoparticles with novel mechanisms.

关键词： catalase-like activity iron oxide nanoparticles autophagy cytotoxicity reactive oxygen species

Quantum dots protect against MPP＋-induced neurotoxicity in a cell model of Parkinson＇s disease through autophagy induction

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Science China Chemistry 2016年第11期59卷 1486-1491页

作者： Lu Wang Xiaoming Li Yuping Han Ting Wang Yun Zhao Aldalbahi Ali Nahed Nasser El-Sayed jiye shi Wenfeng Wang Chunhai Fan Nan Chen Division of Physical Biology and Bioimaging Center Shanghai Synchrotron Radiation FacilityCAS Key Laboratory of Interfacial Physics and TechnologyShanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201800China School of Life Science Sichuan UniversityChengdu 610064China Chemistry Department King Saud UniversityRiyadh 11451Saudi Arabia School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China UCB Pharma SloughSL1 3WEUK

Autophagy is a basic cellular process that decomposes damaged organelles and aberrant proteins. Dysregulation of autophagy is implicated in pathogenesis of neurodegenerative disorders, including Parkinson's disease(PD). Pharmacological compounds that stimulate autophagy can provide neuroprotection in models of PD. Nanoparticles have emerged as regulators of autophagy and have been tested in adjuvant therapy for diseases. In this present study, we explore the effects of quantum dots(QDs) that can induce autophagy in a cellular model of Parkinson's disease. Cd Te/Cd S/Zn S QDs protect differentiated rat pheochromocytoma PC12 cells from MPP+-induced cell damage, including reduced viability, apoptosis and accumulation of α-Synuclein, a characteristic protein of PD. The protective function of QDs is autophagy-dependent. In addition, we investigate the interaction between quantum dots and autophagic pathways and identify beclin1 as an essential factor for QDs-induced autophagy. Our results reveal new promise of QDs in the theranostic of neurodegenerative diseases.

关键词： quantum dots autophagy Parkinson’s disease α-Synuclein Beclin1

Facile Synthesis of 7-epi-Taxane and Its Derivatives and Preliminary Evaluation of Anticancer Activity

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Chinese Journal of Chemistry 2016年第11期34卷 1165-1176页

作者： Zhao Li Jia Feng Kun Zou Zhuo Yang Yong Zhang Zhijian Xu Bo Li jiye shi Yiming Li Weiliang Zhu Kaixian Chen School of Pharmacy Shanghai University of Traditional Chinese Medicine Shanghai 201203 China CAS Key Laboratory of Receptor Research Drug Discovery and Design Centre Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 201203 China Nano Science and Technology Institute University of Science and Technology of China Suzhou Jiangsu 215123 China UCB Biopharma SPRL Chemin du Foriest Braine-l'Alleud Belgium Kellogg College University of Oxford 60-62 Banbury Road Oxford OX2 6PN United Kingdom

7-epi-Taxane has been achieved efficiently in gram scale from natural taxane via inversion of the 7-hydroxyl group simply using Ag20 as catalyst and DMF as solvent. The catalyst could he quantitatively recovered by filtra- tion without loss of catalytic activity. This condition is also applicable to the direct epimerization of taxane derivatives （e.g., docetaxel and paclitaxel） to 7-epi-taxane derivatives （e.g., 7-epi-docetaxel and 7-epi-paclitaxel）. Furthermore, 33 ester derivatives of 7-epi-taxane with different amino acid moieties at the position of C-13 were successfully synthesized via esterification without protecting C-7-OH. Bioassay results revealed that compounds 13 and 18 have good selectivity against prostatic cancer cell line DU145, with ICs0 value as low as 15.9 nmol/L for 18.

关键词： taxane 7-epi-taxane silver oxide amino acid C-13 derivative of taxane anticancer activity

基于CNN和D-S证据理论的多站协同多功能雷达工作模式识别方法

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电子信息对抗技术 2024年第2期39卷 33-39页

作者：于旺石艳宋吉烨黄子纯桂林长海发展有限责任公司桂林541000 绿盟科技股份集团有限公司西安710000 西安电子科技大学电子工程学院西安710071

传统的多功能雷达工作模式识别方法主要利用单一电子侦察设备侦收的脉冲数据完成特征提取,其模型或算法的泛化能力不强。因此,提出基于卷积神经网络(Convolutional Neural Network,CNN)和D-S(Dempster-Shafer)证据理论的多站协同多功能... 详细信息

传统的多功能雷达工作模式识别方法主要利用单一电子侦察设备侦收的脉冲数据完成特征提取,其模型或算法的泛化能力不强。因此,提出基于卷积神经网络(Convolutional Neural Network,CNN)和D-S(Dempster-Shafer)证据理论的多站协同多功能雷达工作模式识别方法。首先,利用轻量级CNN模型对不同方位、不同俯仰下侦察截获分选的脉冲幅度/波形单元数据进行自适应特征提取。其次,利用多站协同侦察系统通过D-S证据理论融合多站协同下不同侦察站点的Softmax分类器的分类结果,实现在差侦察条件下对不同空间方向上的多功能雷达工作模式快速准确识别。仿真验证结果表明,该方法相比于单侦察站条件下具有更好的识别性能。

关键词：工作模式识别卷积神经网络 D-S证据理论多站协同

Preparation,luminescence and photofunctional performances of a hybrid layered gadolinium-europium hydroxide

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Journal of Rare Earths 2022年第9期40卷 1437-1444,I0004页

作者： Lu Liu Jingjie Yu shikao shi jiye Wang Huihua Song Ruikang Zhang Lianshe Fu Hebei Key Laboratory of Inorganic Nanomaterials College of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China Department of Physics CICECO–Aveiro Institute of MaterialsUniversity of Aveiro3810-193AveiroPortugal

The design and fabrication of rare earth ions incorporated into the inorganic/organic hybrid materials have attracted growing attention for seeking improved optical properties and photofunctional *** this paper,a novel hybrid composite based on the layered rare earth hydroxides was successfully prepared by the ion-exchange and intercalation chemical *** rare earth elements in the composite contain gadolinium(Gd)and europium(Eu)and the molar ratio of Gd to Eu is kept constant at 1.9:*** sodium dodecyl sulfonate and dye coumarin-3-carboxyllc acid are simultaneously incorporated into the layered rare earth hydroxides as supporting agent and light-harvesting antenna,*** resulting hybrid layered rare earth hydroxides exhibit the enlarged interlayer distance with about 2.60 nm,and the chemical composition was confirmed through X-ray diffraction,carbon,hydrogen and nitrogen(CHN)elemental analysis,infrared spectroscopy,and thermogravimetric *** layered solid compound shows the characteristic red emission corresponding to the^(5)D_(0)→^(7)F_(2)transition of Eu^(3+)ion,and the luminescence intensity of the optimized compound is greatly enhanced as compared to its corresponding nitrate and the hybrid composite without the introduction of dye *** hybrid layered rare earth hydroxides can be exfoliated into bright colloidal solution,which show superior recognition capability to Cu^(2+)ion with the distinct luminescence *** large quenching constant(1.4×10^(4)L/mol)and low detection limit(0.35μmol/L)are achieved for Cu^(2+)ion,implying a"turn-off"fluorescent sensor for Cu^(2+)***,a transparent film was prepared based on the colloidal solution and displays the typical red emission in folded *** new hybrid compound with enhanced luminescence and excellent photofunctional performances is expected to be applied in the fields of fluorescent sensing and flexible optical devices.

关键词： Layered rare earth hydroxides Luminescence Eu^(3+)ion Gd^(3+)ion Ion-exchange Intercalation chemistry

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英汉被动表达方式的比较

中国电力教育 2008年第13期 254-256页

作者：石继业祖林华北电力大学外国语学院

通过事实对比,提出英汉两种语言中被动句的使用差异现象。并探究了英语多用被动句,汉语少用被动句的根源。其中有思维方式的因素,也有语言习惯的因素,不一而足。

关键词：被动句思维方式语言习惯

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卤键本质与特征的计算化学研究

卤键本质与特征的计算化学研究