检索结果-南通市图书馆

Electrical characteristics of a fractional-order 3×n Fan network

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第4期76卷 176-187页

作者： Zhi-Zhong tan Xin wang Department of Physics Nantong UniversityNantong 226019China

In this article a new achievement of fractional-order 3×n Fan networks is presented.In the first step,the RT-I method is used to derive the general formulae of the equivalent impedance of fractional-order 3×n Fan networks.In the second part,the effects of five system parameters(L,C,n,α and β)on amplitude-frequency and phase-frequency characteristics are analyzed.At the same time,the amplitude-frequency and phase-frequency characteristics of the fractional order 3×n Fan network are revealed by Matlab drawing.This work has important theoretical and practical significance for resistor network models in the field of natural science and engineering technology.

关键词： fractional-order circuit amplitude-frequency characteristics phase-frequency characteristics RT-V theory

Advancing mid-infrared microdisk laser emission with Tm:YAG

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 91-96页

作者： Zhaocong wang Huiqi Li Lei wang Yang tan Feng Chen School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China

Mid-infrared microcavity lasers have important applications in biosensing,mid-infrared spectroscopy,and environmental monitoring.However,the low output power of existing mid-infrared microcavity lasers hinders their practical use.This drawback is attributed to the insufficient laser gain medium,which limits the development of mid-infrared whispering-gallerymode(WGM)lasers.To address this issue,we have employed ion implantation-enhanced etching to fabricate Tm:YAG thin films as effective gain media for mid-infrared WGM lasers.The Tm:YAG thin film,with a thickness of 2μm,exhibits excellent fluorescence characteristics.Subsequently,the Tm:YAG thin film is processed using focused ion beam to form microdisks with a diameter of 30μm.Under 785 nm laser pumping,the maximum output power of the Tm:YAG microdisk at 2023.1 nm is229μW,with a slope efficiency of 2.9%.This work demonstrates the outstanding potential of Tm:YAG as a mid-infrared laser gain medium,providing a new option for the development of mid-infrared lasers.

关键词： microdisk microlaser ultrathin film

Eutectic-derived synthesis of hierarchically nanoporous copper for electrochemical actuation and solar steam generation

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第3期17卷 2011-2018页

作者： Qingguo Bai Yan wang Fuquan tan Zhonghua Zhang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJingshi Road 17923Jinan 250061China School of Applied Physics and Materials Wuyi UniversityDongcheng Village 22Jiangmen 529020China School of Materials Science and Engineering University of JinanWest Road of Nan Xinzhuang 336Jinan 250022China

The utilization of nanoporous copper(np-Cu)as a metallic actuator has gained attention in recent years due to its cost-effectiveness in comparison to other precious metals.Despite this,the enhancement of np-Cu’s actuation performance remains a challenge due to limitations in its strain amplitude and actuation rate.Additionally,np-Cu has been deemed as a promising material for solar absorption due to its localized surface plasmon resonance effect.However,practical applications such as solar steam generators(SSGs)utilizing np-Cu have yet to be documented.In this study,we present the development of hierarchically nanoporous copper(HNC)through the dealloying of a eutectic Al-Cu alloy.The hierarchical structure of the HNC features a combination of ordered flat channels and randomly distributed continuous nanopores,which work in synergy to improve actuation performance.The ordered flat channels,with a sub-micron scale,facilitate rapid mass transport of electrolyte ions,while the nano-sized continuous pores,due to their large specific surface area,enhance the induced strain.Our results indicate that the HNC exhibits improved actuation performance,with a two times increase in both strain amplitude and rate in comparison to other reported np-Cu.Additionally,the HNC,for the first time,showcases excellent solar steam generation capabilities,with an evaporation rate of 1.47 kg·m^(-2)·h^(-1) and a photothermal conversion efficiency of 92%under a light intensity of 1 kW·m^(-2),which rivals that of nanoporous gold and silver film.The enhanced actuation performance and newly discovered solar steam generation properties of the HNC are attributed to its hierarchically porous structure.

关键词： eutectic alloy dealloying hierarchically nanoporous copper(HNC) actuation solar steam generation

One-pot Synthesis of Hierarchical Flower-like WS_(2) Microspheres as Anode Materials for Lithium-ion Batteries

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

Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 1-6页

作者：张向华 tan Hen wang Ze XUE Maoquan School of Mechanical Engineering Jiangsu University of TechnologyChangzhou 213001China School of Materials Engineering Jiangsu University of TechnologyChangzhou 213001China Changzhou Vocational Institute of Industry Technology Changzhou 213164China

3D hierarchical flowerlike WS_(2) microspheres were synthesized through a facile one-pot hydrothermal route.The as-synthesized samples were characterized by powder X-ray powder diffraction (XRD),energy-dispersive spectroscopy (EDS),scanning electron microscopy (SEM) and Raman.SEM images of the samples reveal that the hierarchical flowerlike WS_(2) microspheres with diameters of about 3-5μm are composed of a number of curled nanosheets.Electrochemical tests such as charge/discharge,cyclic voltammetry,cycle life and rate performance were carried out on the WS_(2) sample.As an anode material for lithium-ion batteries,hierarchical flowerlike WS_(2) microspheres show excellent electrochemical performance.At a current density of100 mA·g^(-1),a high specific capacity of 647.8 mA·h·g^(-1) was achieved after 120 discharge/charge cycles.The excellent electrochemical performance of WS_(2) as an anode material for lithium-ion batteries can be attributed to its special 3D hierarchical structure.

关键词： WS_(2) microspheres lithium-ion batteries electrochemical performance

Exploration on electrical resistance tomography in characterizing the slurry spatial distribution in cemented granular materials

在线全文

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第3期18卷 365-379页

作者： Bohao wang Wei wang Feng JIN Handong tan Ning LIU Duruo HUANG State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing 100084China Institute of Science and Technology China Three Gorges CorporationBeijing 100038China School of Geophysics and Information Technology China University of GeosciencesBeijing 100083China

This study investigated the application of electrical resistance tomography(ERT)in characterizing the slurry spatial distribution in cemented granular materials(CGMs).For CGM formed by self-flow grouting,the voids in the accumulation are only partially filled and the bond strength is often limited,which results in difficulty in obtaining in situ samples for quality evaluation.Therefore,it is usually infeasible to evaluate the grouting effect or monitor the slurry spatial distribution by a mechanical method.In this research,the process of grouting cement paste into high alumina ceramic beads(HACB)accumulation is reliably monitored with ERT.It shows that ERT results can be used to calculate the cement paste volume in the HACB accumulation,based on calibrating the saturation exponent n in Archie’s law.The results support the feasibility of ERT as an imaging tool in CGM characterization and may provide guidance for engineering applications in the future.

关键词： electrical resistance tomography cemented granular material grouting spatial distribution Archie’s law

Investigation of formaldehyde sources and its relative emission intensity in shipping channel environment

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

Journal of Environmental Sciences 2024年第8期142卷 142-154页

作者： Jiaqi Liu Shanshan wang Yan Zhang Yuhao Yan Jian Zhu Sanbao Zhang Tianyu wang Yibing tan Bin Zhou Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200433China Institute of Eco-Chongming(IEC) No.20 Cuiniao RoadShanghai 202162China Institute of Atmospheric Sciences Fudan UniversityShanghai 200433China National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary Fudan UniversityShanghai 200438China Institute of Digitalized Sustainable Transformation Big Data InstituteFudan UniversityShanghai 200433China

Formaldehyde(HCHO)is considered one of the most abundant gas-phase carbonyl compounds in the atmosphere,which can be directly emitted through transportation sources.Long-Path Differential Optical Absorption Spectroscopy(LP-DOAS)was used to observe HCHO in the river channel of Wusong Wharf in Shanghai,China for the whole year of 2019.Due to the impact of ship activity,the annual average HCHO level in the channel is about2.5 times higher than that in the nearby campus environment.To explain the sources of HCHO under different meteorological conditions,the tracer-pair of CO and O_(x)(NO_(2)+O_(3))was used on the clustered air masses.The results of the source appointment show that primary,secondary and background account for 24.14%(3.34±1.19 ppbv),44.78%(6.20±2.04ppbv)and 31.09%(4.31±2.33 ppbv)of the HCHO in the channel when the air masses were from the mixed direction of the city and channel,respectively.By performing background station subtraction at times of high primary HCHO values and resolving the plume peaks,directly emitted HCHO/NO_(2)in the channel environment and plume were determined to be mainly distributed between 0.2 and 0.3.General cargo ships with higher sailing speeds or main engine powers tend to have higher HCHO/NO_(2)levels.With the knowledge of NO_(2)(or NO_(x))emission levels from ships,this study may provide data support for the establishment of HCHO emission factors.

关键词： HCHO LP-DOAS Channel environment Ship emissions

Emergence of machine language: towards symbolic intelligence with neural networks

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第4期11卷 27-30页

作者： Yuqi wang Xu-Yao Zhang Cheng-Lin Liu Tieniu tan Zhaoxiang Zhang State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of Sciences

Representation learning is a core issue in artificial intelligence (AI). Currently,there exists a disparity in the choice of representation between humans and machines. Humans rely on discrete language for communicati...

关键词：

Clinical applications of stem cell-derived exosomes

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Signal Transduction and Targeted Therapy 2024年第2期9卷 621-651页

作者： Fei tan Xuran Li Zhao wang Jiaojiao Li Khawar Shahzad Jialin Zheng Department of ORL-HNS Shanghai Fourth People’s Hospitaland School of MedicineTongji UniversityShanghaiChina Plasma Medicine and Surgical Implants Center Tongji UniversityShanghaiChina The Royal College of Surgeons in Ireland DublinIreland The Royal College of Surgeons of England LondonUK Center for Translational Neurodegeneration and Regenerative Therapy Tongji Hospital affiliated to Tongji University School of MedicineShanghaiChina Shanghai Frontiers Science Center of Nanocatalytic Medicine Tongji UniversityShanghaiChina

Although stem cell-based therapy has demonstrated considerable potential to manage certain diseases more successfully than conventional surgery,it nevertheless comes with inescapable drawbacks that might limit its clinical translation.Compared to stem cells,stem cell-derived exosomes possess numerous advantages,such as non-immunogenicity,non-infusion toxicity,easy access,effortless preservation,and freedom from tumorigenic potential and ethical issues.Exosomes can inherit similar therapeutic effects from their parental cells such as embryonic stem cells and adult stem cells through vertical delivery of their pluripotency or multipotency.After a thorough search and meticulous dissection of relevant literature from the last five years,we present this comprehensive,up-to-date,specialty-specific and disease-oriented review to highlight the surgical application and potential of stem cell-derived exosomes.Exosomes derived from stem cells(e.g.,embryonic,induced pluripotent,hematopoietic,mesenchymal,neural,and endothelial stem cells)are capable of treating numerous diseases encountered in orthopedic surgery,neurosurgery,plastic surgery,general surgery,cardiothoracic surgery,urology,head and neck surgery,ophthalmology,and obstetrics and gynecology.The diverse therapeutic effects of stem cells-derived exosomes are a hierarchical translation through tissue-specific responses,and cell-specific molecular signaling pathways.In this review,we highlight stem cell-derived exosomes as a viable and potent alternative to stem cell-based therapy in managing various surgical conditions.We recommend that future research combines wisdoms from surgeons,nanomedicine practitioners,and stem cell researchers in this relevant and intriguing research area.

关键词： viable stem capable

MXene Hollow Spheres Supported by a C–Co Exoskeleton Grow MWCNTs for Efficient Microwave Absorption

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

Nano-Micro Letters 2024年第6期16卷 76-94页

作者： Ze Wu Xiuli tan Jianqiao wang Youqiang Xing Peng Huang Bingjue Li Lei Liu School of Mechanical Engineering Southeast UniversityNanjing 211189People’s Republic of China

High-performance microwave absorption(MA) materials must be studied immediately since electromagnetic pollution has become a problem that cannot be disregarded. A straightforward composite material, comprising hollow MXene spheres loaded with C–Co frameworks, was prepared to develop multiwalled carbon nanotubes(MWCNTs). A high impedance and suitable morphology were guaranteed by the C–Co exoskeleton, the attenuation ability was provided by the MWCNTs endoskeleton, and the material performance was greatly enhanced by the layered core–shell structure. When the thickness was only 2.04 mm, the effective absorption bandwidth was 5.67 GHz, and the minimum reflection loss(RLmin) was-70.70 d B. At a thickness of 1.861 mm, the sample calcined at 700 ℃ had a RLmin of-63.25 d B. All samples performed well with a reduced filler ratio of 15 wt%. This paper provides a method for making lightweight core–shell composite MA materials with magnetoelectric synergy.

关键词： MXene C-Co skeleton MWCNTs Microwave absorption