检索结果-南通市图书馆

Interface strengthening for thermal sprayed WC-10Co4Cr coating subjected to pulsed magnetic treatment

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第2期43卷 780-795页

作者： Cheng-Kai Qian qu Liu Heng Wang Ke-jian Li Zhi-Peng Cai Department of Mechanical Engineering Tsinghua UniversityBeijing100084China Tianjin Research Institute for Advanced Equipment Tsinghua UniversityTianjin300304China State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing100084China

The reliability of the coated industry components demands ideal fatigue properties of the coating,and it is mainly determined by the performance of the *** this study,pulsed magnetic treatment(PMT)was applied to the thermal sprayed WC-10Co4Cr coating,and the fatigue lifetime of the coated bolt increased by 219.82%under an imitation of the operating mode *** tests further proved that both the adhesion and cohesion strength were improved after PMT,and they benefit from the interface strengthening *** formation of coherent WC/Co interfaces was characterized by in-situ transmission electron microscopy(TEM),and the molecular dynamic simulations indicate that the work of separation of these interfaces is much higher than the original disordered *** stress was relaxed and distributed more homogeneously after PMT,and it mainly contributes to the coating/substrate *** work provides a new post-treatment method focusing on the interfaces in the WC-based coating and gives insight into its mechanism so that it is hopeful to be applied to other kinds of coatings.

关键词： Cemented carbide coating Pulsed magnetic treatment Interface strengthening Fatigue properties Adhesion strength

Neg-Entropy Mechanism as a Target for Natural Medicines

在线全文

学校读者我要写书评

暂无评论

Engineering 2024年第7期38卷 11-12页

作者： Tian-Le Gao hui-hui Guo jian-Dong jiang Institute of Materia Medica Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Current strategies for drug discovery research mainly focus on molecular targets,in which structure biology plays a central role,such as the detailed mechanism of a drug-target *** principle of this approach is the presumed molecular mechanism or genetic background of the disease being *** this approach has brought progress in understanding the mode of action for some drugs,most prevalent illnesses-especially chronic diseases-are multifactorial and present with a group of symptoms,as is often the case in cardiovascular diseases,metabolic disorders,cancers,and so *** newly emerging term“multi-morbidity”(i.e.,multiple co-occurring diseases)describes a grand challenge for this strategy,and successful drug intervention for multimorbidity should be multifaceted[1].So,our research team has shifted its attention to a new direction that views the disease as a whole instead of a single-molecule abnormality,and focusing on drugs with multiple targets.

关键词： drugs diseases cardiovascular

A Single-Fluorophore Multicolor Molecular Sensor That Visually Identifies Organic Anions Including Phosphates

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CCS Chemistry 2024年第3期6卷 774-782页

作者： Zezhou Zong Qi Zhang Da-hui qu Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237

Developing fluorescent sensors for small-molecule phosphates offers opportunities in optically detecting biorelevant reactions and ***,it remains elusive how to identify phosphates from other anions,such as carboxylates and sulfates,because current synthetic phosphate receptors lack *** we report the construction of a multicolor fluorescent sensor that can identify phosphates from other analogous *** key design principle is to take advantage of the highly sensitive conformation-dependent emissive wavelength of diphenyl-9,14-dihydrodibenzo[a,c]phenazine fluorophores to sense the minor structural differences between phosphates and other anions,for example,sulfates and *** effect of structural factors such as spacer length and urea versus thiourea has been investigated by comparing the optical properties and binding affinities with the phosphate *** strategy provides a simple and robust fluorescent sensing solution to optically analyze small-molecule phosphates with antiinterference performance.

关键词： fluorescent sensors photoluminescence host-guest chemistry supramolecular chemistry noncovalent bonds

Influence of Incomplete Soil Plugs on Bearing Capacities of Bucket Foundations in Clay

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Ocean Engineering 2024年第1期38卷 144-155页

作者： LI hui-shan LIU Run YANG Xu LIAN Ji-jian State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China Institute of Marine Energy and Intelligent Construction Tianjin University of TechnologyTianjin 300384China

Due to the uneven seabed and heaving of soil during pumping,incomplete soil plugs may occur during the installation of bucket foundations,and the impacts on the bearing capacities of bucket foundations need to be *** this paper,the contact ratio(the ratio of the top diameter of the soil plug to the diameter of the bucket)and the soil plug ratio(the ratio of the soil heave height to the skirt height)are defined to describe the shape and size of the incomplete soil ***,finite element models are established to investigate the bearing capacities of bucket foundations with incomplete soil plugs and the influences of the contact ratios,and the soil plug ratios on the bearing capacities are *** results show that the vertical bearing capacity of bucket foundations in homogeneous soil continuously improves with the increase of the contact ***,in normally consolidated soil,the vertical bearing capacity barely changes when the contact ratio is smaller than 0.75,while the bearing capacity suddenly increases when the contact ratio increases to 1 due to the change of failure *** contact ratio hardly affects the horizontal bearing capacity of bucket ***,the moment bearing capacity improves with the increase of the contact ratio for small aspect ratios,but hardly varies with increasing contact ratio for aspect ratios larger than ***,the reduction coefficient method is proposed based on this analysis to calculate the bearing capacities of bucket foundations considering the influence of incomplete soil *** comparison results show that the proposed reduction coefficient method can be used to evaluate the influences of incomplete soil plug on the bearing capacities of bucket foundations.

关键词： bucket foundation incomplete soil plug uniaxial bearing capacity contact ratio soil plug ratio

Controlling molecular assembly on time scale:Time-dependent multicolor fluorescence for information encryption

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第7期35卷 336-340页

作者： Zixi Zou Jingyuan Wang Yian Sun Qian Wang Da-hui qu Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Dynamic assembly on time scale is common in biological systems but rare for artificial materials,especially for smart luminescent *** molecular assembly in a spatio-temporal manner and resulting in white-light-including multicolor fluorescence with time-dynamic features remains ***,controlling molecular assembly on time scale is achieved by integrating a pH-responsive motif to a transient alkaline solution which is fabricated by activators(NaOH)and deactivators(esters),leading to automatic assembly on time scale and time-dependent multicolor fluorescence changing from blue to white and *** kinetics of the assembly process is dependent on the ester hydrolysis process,which can be controlled by varying ester concentrations,temperature,initial pH,stirring rate and ester *** dynamic fluorescent system can be further developed for intelligent fluorescent materials such as fluorescent ink,three-dimension(3D)codes and even four-dimension(4D)codes,exhibiting a promising potential for information encryption.

关键词： Supramolecular chemistry Multicolor fluorescence White light emission Time-dependent fluorescence Information encryption

Strong field ionization of molecules on the surface of nanosystems

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第4期33卷 25-34页

作者：曲棋文孙烽豪王佳伟高健李辉吴健 State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China Chongqing Key Laboratory of Precision Optics Chongqing Institute of East China Normal UniversityChongqing 401121China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China CAS Center for Excellence in Ultra-Intense Laser Science Shanghai 201800China

Besides the diverse investigations on the interactions between intense laser fields and molecular systems,extensive research has been recently dedicated to exploring the response of nanosystems excited by well-tailored femtosecond laser *** to the fact that nanostructures hold peculiar effects when illuminated by laser pulses,the underlying mechanisms and the corresponding potential applications can make significant improvements in both fundamental research and development of novel *** this review,we provide a summarization of the strong field ionization occurring on the surface of *** molecules attached to the nanoparticle surface perform as the precursor in the ionization and excitation of the whole nanosystem,the fundamental processes of which are yet to be *** discuss the influence on nanoparticle constituents,geometric shapes and sizes,as well as the specific waveforms of the excitation laser *** intriguing characteristics observed in surface ion emission reflect how enhanced near field affects the localized ionizations and nanoplasma expansions,thereby paving the way for further precision controls on the light-and-matter interactions in the extreme spatial temporal levels.

关键词： nanoparticle femtosecond laser field local field enhancement

Vibration Suppression for Active Magnetic Bearings Using Adaptive Filter with Iterative Search Algorithm

在线全文

学校读者我要写书评

暂无评论

CES Transactions on Electrical Machines and Systems 2024年第1期8卷 61-71页

作者： Jin-hui Ye Dan Shi Yue-Sheng Qi Jin-hui Gao jian-Xin Shen IEEE Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China CES and IEEE

Active Magnetic Bearing(AMB) is a kind of electromagnetic support that makes the rotor movement frictionless and can suppress rotor vibration by controlling the magnetic force. The most common approach to restrain the rotor vibration in AMBs is to adopt a notch filter or adaptive filter in the AMB controller. However, these methods cannot obtain the precise amplitude and phase of the compensation current. Thus, they are not so effective in terms of suppressing the vibrations of the fundamental and other harmonic orders over the whole speed range. To improve the vibration suppression performance of AMBs,an adaptive filter based on Least Mean Square(LMS) is applied to extract the vibration signals from the rotor displacement signal. An Iterative Search Algorithm(ISA) is proposed in this paper to obtain the corresponding relationship between the compensation current and vibration signals. The ISA is responsible for searching the compensating amplitude and shifting phase online for the LMS filter, enabling the AMB controller to generate the corresponding compensation force for vibration suppression. The results of ISA are recorded to suppress vibration using the Look-Up Table(LUT) in variable speed range. Comprehensive simulations and experimental validations are carried out in fixed and variable speed range, and the results demonstrate that by employing the ISA, vibrations of the fundamental and other harmonic orders are suppressed effectively.

关键词： Active Magnetic Bearing(AMB) Adaptive filter Iterative search algorithm Least mean square(LMS) Vibration suppression

Interface interaction between SiO_(2) and magnetite under high temperature:particle migration and inhibition mechanism

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2024年第3期31卷 561-572页

作者： Yao-zu Wang jian-liang Zhang Qiang Cheng hui-qing jiang Zheng-jian Liu Yu-bo Tan School of Intelligent Science and Technology University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Advanced Engineering University of Science and Technology BeijingBeijing 100083China

Silicon is one of the main gangue components in iron ore,usually in the form of quartz and *** studies have shown that SiO_(2) has a two-sided effect on the consolidation of pellets during high-temperature oxidation roasting of ***,it is very difficult to capture the structural evolution and migration mechanisms during high-tem-perature roasting process by existing experimental ***,the influence of SiO_(2) on the consolidation behavior of magnetite was studied through a series of roasting experiments and molecular dynamic *** results show that the consolidation index and particle growth index decrease with the increase in SiO_(2) content in the *** 1573 K,the liquid phase promotes the recrystallization growth of hematite at high *** dynamic study shows that it is difficult for quartz SiO_(2) to form sintering neck with Fe_(2)O_(3).When the calcination temperature is higher than 1400 K,the Fe_(2)O_(3)-Fe_(2)SiO_(4) system produces a considerable sintering neck structure after *** atomic migration ability of Fe_(2)SiO_(4) is much higher than that of Fe_(2)O_(3).The higher atomic migration ability of Fe_(2)SiO_(4) is the main reason for the formation of the sintering neck.

关键词： Sintering neck Crystal growth Consolidation Molecular dynamics SiO_(2)

Multi-scale collaborative design method for macroscopic thermal optimization and mesoscopic woven structure of hypersonic vehicle's TOCMC leading edge

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第4期37卷 524-541页

作者： Chenwei ZHAO Zecan TU Junkui MAO jian hui Pingting CHEN College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 21016China Integrated Energy Institute Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A new thermal protection design method for hypersonic vehicle's leading edge is proposed, which can effectively reduce temperature of the leading edge without additional cooling measures. This method reduces the leading-edge's temperature by the multi-scale collaborative design of the macroscopic thermal optimization and the mesoscopic woven structures of Three-dimensional Orthogonal Woven Ceramic Matrix Composites(TOCMC). The macroscopic thermal optimization is achieved by designing different mesoscopic woven structures in different regions to create combined heat transfer channels to dredge the heat. The combined heat transfer channel is macroscopically represented by the anisotropic thermal conductivity of TOCMC. The thermal optimization multiple linear regression model is established to optimize the heat transport channel, which predicts Theoretical Optimal Thermal Conductivity Configuration(TOTCC) in different regions to achieve the lowest leading-edge temperature. The function-oriented mesostructure design method is invented to design the corresponding mesostructure of TOCMC according to the TOTCC, which consists of universal thermal conductivity prediction formulas for TOCMC. These universal formulas are firstly derived based on the thermal resistance network method, which is verified by experiments with an error of 6.25%. The results show that the collaborative design method can effectively reduce the leading edge temperature by about 12.8% without adding cooling measures.

关键词： Multi-scale collaborative design Thermal optimization Ceramic matrix composite Hypersonic vehicle Thermal protection Intelligent optimization