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Melanin/polydopamine-based nanomaterials for biomedical applications

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Science China Chemistry 2019年第2期62卷 162-188页

作者： Chao Qi Lian-Hua fu Han Xu tian-fu wang Jing Lin Peng Huang Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging Carson International Cancer Center Laboratory of Evolutionary Theranostics School of Biomedical Engineering Health Science Center Shenzhen University Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Optoelectronic Engineering Shenzhen University

The natural melanin is one kind of ubiquitous biological pigments, which is produced in melanosomes and widely distributed in living organisms. The synthetic melanin, often known as polydopamine(PDA), has similar chemical compositions and physical properties to natural melanin. In recent years, both natural melanin and PDA have aroused increased research interests in biomedical fields owing to their inherent biocompatibility, antioxidant activity, free-radical scavenging, metal ion chelation,strong near-infrared absorption and high photothermal conversion efficiency. Inspired by these fascinating properties, melanin and PDA have been widely used as building blocks for the construction of multifunctional nanoplatforms for various biomedical applications. This review focuses on the state-of-the-art progress in melanin/PDA-based nanomaterials, which covers from their preparation methods to biomedical applications including bioimaging, treatment, theranostics, antibacterial, UV/radiation protection, biosensor and tissue engineering. Moreover, the current trends and the future prospects of melanin/PDA-based nanomaterials are also discussed.

关键词： melanin polydopamine nanomaterials biomedical applications

Effect of δ Phase on Microstructure and Hardness of Heat-Affected Zone in TIG-Welded GH4169 Superalloy

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Acta Metallurgica Sinica(English Letters) 2019年第8期32卷 1041-1052页

作者： tian-fu wang Xin-Jie Di Cheng-Ning Li Jia-Mei wang Dong-Po wang School of Materials Science and Engineering Tianjin UniversityTianjin 300350China tianjin Key Laboratory of Advanced Joining Technology Tianjin 300350China

The GH4169 superalloy with different content ofδ-Ni3Nb phase was welded by tungsten inert gas welding.A detailed study of microstructure and hardness of heat-affected zone(HAZ)was performed in both as-welded and aged state.The results show that the precipitation ofδphase,especially the intergranularδphase,can lead to the enrichment of Nb and Mo elements,which promote the formation ofγ/Laves eutectic constituent at grain boundaries in HAZ.In as-welded state,the hardness decreases first and then increases(exhibiting a"V"shape)with distance away from fusion line in HAZ,which is governed by grain size.After aging treatment,however,theγ″phase plays a key role in hardness and leads to the"■"shape profiles of hardness in HAZ.

关键词： GH4169 superalloy TIG(tungsten inert gas)welding δphase γ″phase Element enrichment

A new scheme of coded ultrasound using Golay codes

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第6期11卷 476-480页

作者： Cheng JIN Si-ping CHEN Zheng-di QIN tian-fu wang School of Medicine Shenzhen University Shenzhen 518060 China School of Biomedical Engineering and Instrument Science Zhejiang University Hangzhou 310027 China

Golay codes are the most practical code in coded ultrasound imaging systems.But the trade-off for perfect range sidelobe cancellation is the requirement for two firings, thus resulting in motion-dependent decoding errors.In view of this, we propose a new scheme using the simultaneous emission of code pairs.The code pair is allocated to different elements of an aperture and transmitted simultaneously.The process of separating the code pair from the echo received is based on the orthogonality of the code pair.At last the autocorrelation functions of the individual Golay codes are added together.The simultaneous emission of code pairs instead of two firings recovers the frame rate loss, and eliminates the motion-dependent decoding error.Our theoretical analysis and simulations show that the scheme can be used to eliminate the tissue motion effects.

关键词： Coded ultrasound Golay codes Tissue motion Ultrasonic imaging

Effect of Al content in molten steel on interaction between MgO-C refractory and SPHC steel

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Journal of Iron and Steel Research(International) 2024年第4期31卷 838-848页

作者： fu-bin Gao fu-ming wang Xiang Zhang tian-yu Du Xin-hua wangg School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Handan Iron and Steel Company Hegang GroupHandan 056015HebeiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The effect of Al content in molten steel on the interaction between SPHC steel(0.005-0.068 wt.%Al,and 19×10^(-4)-58×10^(-4)wt.%O)and MgO-C refractory(11.63 wt.%C)was investigated.Non-metallic inclusions in the steel were examined at various periods(0,5,15,30,45,and 60 min)as well as the MgO-C interface after 60 min of corrosion at 1600℃.The results show that when MgO-C refractory comes into contact with SPHC steel,the refractory interface consists of three layers arranged from the innermost to the outermost,including the original refractory layer,the dense MgO layer,and the iron infiltration layer.The carbon in the MgO-C refractories and the Al content in the molten steel undergo a reaction with the MgO in the refractories,resulting in an increase in Mg concentration in the steel.Increasing Al content in the molten steel from 0.005 to 0.068 wt.%causes a spinel layer to appear at the interface,and the disappearance time of Al_(2)O_(3) inclusions in the steel decreases from 60 to 30 min,while the average MgO content in inclusions increases.Therefore,controlling the Al content in the molten steel and the smelting duration can help regulate the formation of spinel inclusionsinthe steel.

关键词： MgO-C refractory SPHC steel Inclusion-Spinel Al-killed steel Interfacial reaction

Solid particle size characterization by a high-frequency collision response in pneumatic particulate flow

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Particuology 2024年第3期86卷 39-54页

作者： Kai wang Yichen Li Ziang Chang Min Qin Guangming fu Bangtang Yin Gang wang jiaqi tian School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580China Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Ministry of EducationQingdao266580China National Engineering Research Center of Oil&Gas Drilling and Completion Technology Qingdao266580China Shock and Vibration of Engineering Materials and Structures Key Lab ofSichuan Province Southwest University of Science and TechnologyMianyang621000China

A novel triaxial vibration method is developed for the real-time characterization of the solid particle size distribution(PsD)in pneumatic particulate flow,which is critical for chemical industry.In this work,the particle-wall collision and friction behaviours were analysed by the time-domain statistical and timefrequency joint methods to narrow the high-frequency response range by the initial experiment of free fall for a single particle,interparticle,and multiple particles.Subsequently,verification experiments of PSD characterization in pneumatic flow were performed.First,the quantitative triaxial energy response model that considers the particle size,shape,and mass factors were established.Second,a good agreement of the particle number identification was found between the triaxial vibration energy and mean particle size of 150-550μm.Moreover,the performance with the best accuracy was focused on a range of 42-43 kHz in the x-axis and z-axis and 36.8-38.8 kHz in the y-axis.Finally,the individual particle energy was inversely analysed by the triaxial vibration response within the optimized frequency bands,and the PSD was characterized in real-time by a low error rate,that is,5.2% from the XZ-axis direction of sand(42-43 kHz)and 5.6% from the XYZ-axis of glass(30.9-33.9 kHz,46.2-47.2 kHz,38.3-41.3 kHz for each axis response).Therefore,this research complements the existing approaches for PsD characterization in particulate multiphase flow.

关键词： Solid particulate flow Triaxial vibration High-frequency response Particle wall Particle size distribution

RGB oralscan video-based orthodontic treatment monitoring

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Science China(Information Sciences) 2024年第1期67卷 124-139页

作者： Yan tian Hanshi fu Hao wang Yuqi LIU Zhaocheng XU Hong CHEN Jianyuan LI Ruili wang School of Computer Science and Technology Zhejiang Gongshang University Shining3D Tech Co. Ltd. School of Information and Technology Monash University School of Mathematical and Computational Sciences Massey University Department of Stomatology Zhejiang Provincial People's HospitalHangzhou Medical College School of Computer and Computing Science Zhejiang University City College

Orthodontic treatment monitoring involves using current images and previous 3D models to estimate the relative position of individual teeth before and after orthodontic treatment.This process differs from image-based object 6D pose estimation due to the gingiva deformation and varying pose offsets for each tooth during treatment.Motivated by the fact that the poses of molars remain relatively fixed in implicit orthodontics,we design an approach that employs multiview pose evaluation and bidirectional temporal propagation for jaw pose estimation and then employs an iteration-based method for tooth alignment.To handle changes in tooth appearance or location with weak texture across frames,we also introduce an instance propagation module that leverages positional and semantic information to explore instance relations in the temporal domain.We evaluated the performance of our approach using both the Shining3D tooth pose dataset and the Aoralscan3 tooth registration dataset.Our experimental results demonstrate remarkable accuracy improvements compared with existing methods.

关键词： digital dentistry object 6D pose estimation deep learning computer vision

Preparation of Self-limiting Heating Cables with Excellent Processability, Mechanical Properties and PTC Effect via Thermal and Electrical Treatments

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Chinese Journal of Polymer Science 2024年第4期42卷 511-520页

作者： tian-Hao Yang Tong Wu Qiang fu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu610065China

Polymer/conductive filler composites have been widely used for the preparation of self-limiting heating cables with the positive temperature coefficient (PTC) effect. The control of conductive filler distribution and network in polymer matrix is the most critical for performance of PTC materials. In order to compensate for the destruction of the filler network structure caused by strong shearing during processing, an excessive conductive filler content is usually added into the polymer matrix, which in turn sacrifices its processability and mechanical properties. In this work, a facile post-treatment of the as-extruded cable, including thermal and electrical treatment to produce high-density polyethylene (HDPE)/carbon black (CB) cable with excellent PTC effect, is developed. It is found for the as-extruded sample, the strong shearing makes the CB particles disperse uniformly in HDPE matrix, and 25 wt% CB is needed for the formation of conductive paths. For the thermal-treated sample, a gradually aggregated CB filler structure is observed, which leads to the improvement of PTC effect and the notable reduction of CB content to 20 wt%. It is very interesting to see that for the sample with combined thermal and electrical treatment, CB particles are agglomerated and oriented along the electric field direction to create substantial conductive paths, which leads to a further decrease of CB content down to 15 wt%. In this way, self-limiting heating cables with excellent processability, mechanical properties and PTC effect have simultaneously been achieved.

关键词： Self-limiting heating cables Positive temperature coefficient Thermal treatment Electrical treatment

ANALYSIS OF FIRST TRANSIENT PRESSURE OSCILLATION FOR LEAKDETECTION IN A SINGLE PIPELINE

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Journal of Hydrodynamics 2012年第3期24卷 363-370页

作者： YANG Kai-lin LI fu-tian wang Tao fu hui State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of WaterResources and Hydropower Research Beijing 100038 China

The leak detection is of great importance in the reliable operation and management of a pipeline system. Recently, attention is shifted to the use of the time domain or frequency domain methods based on the transient analysis. These methods sometimes require accurate pressure signals obtained during the transient period or by creating ideal conditions in testing. This paper proposes a method that does not require transient simulations over the whole or an extended period of time, but uses the first transient pressure oscillation to detect leaks. The method considers the propagation of the pressure oscillation wave created from a fast valve closure and the reflected damp wave from the leak. A leak in the pipe gives rise to reflected waves which in turn create discontinuities in the observed signal at the measurement section. The timing of the reflected damp wave and the magnitude represent the location and the size of the leak, respectively. An analytical expression is derived based on the Method Of Characteristic （MOC） for the relationship between the leakage and the reflected magnitude. The leak detection procedure based on the method is also given. Then the reliability of the method is tested on numerically simulated pressure signals and experimental pressure signals with calibrated leak parameters, and the results indicate a successful application and the promising features of the method.

关键词： leak detection hydraulic transient pressure oscillation pipeline

Constructing oxygen deficiency-rich V_(2)O_(3)@PEDOT cathode for high-performance aqueous zinc-ion batteries

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Rare Metals 2024年第2期43卷 635-646页

作者： Dong-Fei Sun Zi-Juan wang tian tian Xin Yu Dan-Dan Yu Xiao-Zhong Zhou Guo-fu Ma Zi-Qiang Lei Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-environmental Polymer Materials of Gansu ProvinceSchool of College of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou730070China

Aqueous zinc-ion batteries(AZIBs)have attracted widespread attention due to the advantages of high safety and environmental friendliness.Although V_(2)O_(3) is a promising cathode,the strong electrostatic interaction between Zn^(2+) and V_(2)O_(3) crystal,and the sluggish reaction kinetics still limit their application in AZIBs.Herein,the oxygen defects rich V_(2)O_(3) with conducive poly(3,4-ethylenedioxythiophene)(PEDOT)shell(V_(2)O_(3)-Od@PEDOT)was fabricated for AZIBs by combining the sulfur-assisted thermal reduction and in-situ polymerization method.The introduced oxygen vacancies of V_(2)O_(3)–Od@PEDOT weaken the electrostatic interaction between Zn^(2+) and the host material,improving the interfacial electron transport,while the PEDOT coating enhances the structural stability and conductivity of V_(2)O_(3),thus accelerating the reaction kinetics.Based on the advantages,V_(2)O_(3)–Od@PEDOT electrode delivers a reversible capacity of 495 mAh·g^(−1) at 0.1 A·g^(−1),good rate capability(189 mAh·g^(−1)at 8.0 A·g^(−1)),and an impressive cycling stability with 90.1%capacity retention over 1000 cycles at 8.0 A·g^(−1).The strategy may provide a path for exploiting the other materials for high performance AZIBs.

关键词： Oxygen defects V_(2)O_(3) PEDOT Electrochemical self-optimization Aqueous zinc-ion batteries