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Mechanism and prediction of failure of diamond films deposited on various substrates by HFCVD

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中国有色金属学会会刊：英文版 2004年第z1期14卷 229-233页

作者： ZHOU ling-ping SUN Xin-yuan li Shao-lu li De-yi CHEN xiao-hua College of Material Science and Engineering Hunan University Changsha 410082 China College of Material Science and Engineering Hunan University Changsha 410082 China College of Material Science and Engineering Hunan University Changsha 410082 China College of Material Science and Engineering Hunan University Changsha 410082 China College of Material Science and Engineering Hunan University Changsha 410082 China

Diamond films were deposited on the WC-Co cemented carbide and Si3N4 ceramic cutting tool substrates by hot-filament-assisted chemical vapour deposition. The adherence property of diamond films was estimated using the critical load (Pcr) in the indentation test. The adhesive strength of diamond films is related to the intermediate layer between the film and the substrate. Poor adhesion of diamond films to polished cemented carbide substrate is owing to the formation of graphite phase in the interface. The adhesion of diamond films deposited on acid etched cemented carbide substrate is improved, and the peeling-off of the films often happens in the loosen layer of WC particles where the cobalt element is nearly removed. The diamond films' adhesion to cemented carbide substrate whose surface layer is decarbonizated is strengthened dramatically because WC phase forms by reaction between the deposited carbon and tungsten in the surface layer of substrates during the deposition of diamond, which results in chemical combination in the film-substrate interface. The adhesion of diamond films to silicon nitride substrate is the firmest due to the formation of chemical combination of the SiC intermediate layer in the interfaces. In the piston-turning application, the diamond-coated Si3N4 ceramic and the cemented carbide cutting tools usually fail in the form of collapsing of edge and cracking or flaking respectively. They have no built-up edge(BUE) as long as coating is *** it wears through, BUE develops and the cutting force on it increases 1 - 3 times than that prior to failure. This can predict the failure of diamond-coated cutting tools.

关键词： diamond film cutting tool adhesion failure prediction cemented carbide

Durable Design of Superhydrophobic Coatings with TiO_(2)Particles and Al_(2)O_(3)Whiskers for the Enhanced Anti-icing Performance

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Journal of Bionic Engineering 2024年第3期21卷 1360-1374页

作者： Weilan liu Kunlong li Yizhou Shen Huanyu Zhao Yaru Ni Zeyu Cai lingfeng Zhao zhen Wang Institute of Advanced Materials(IAM) School of Materials Science and EngineeringNanjing Tech UniversityNanjing211816China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing211100China Aviation Industry Aerodynamics Research Institute of China Shenyang110000China

Superhydrophobic coatings with high non-wetting properties are widely applied in anti-icing ***,the micro-nanostructures on the surfaces of superhydrophobic coatings are fragile under external forces,resulting in reduced ***,mechanical strength and durability play a crucial role in the utilization of superhydrophobic *** this study,we employed a two-step spraying method to fabricate superhydrophobic FEVE-based coatings with exceptional mechanical durability,utilizing fluorinated TiO_(2)nanoparticles and fluorinated Al_(2)O_(3)microwhiskers as the *** composite coating exhibited commendable non-wetting properties,displaying a contact angle of 164.84°and a sliding angle of 4.3°.On this basis,the stability of coatings was significantly improved due to the interlocking effect of Al_(2)O_(3)*** 500 tape peeling cycles,500 sandpaper abrasion tests,and 50 kg falling sand impact tests,the coatings retained superhydrophobicity,exhibiting excellent durability and application ***,the ice adhesion strength on the coatings was measured at only 65.4 kPa,while the icing delay time reached 271.8 s at-15℃.In addition,throughout 500 freezing/melting cycles,statistical analysis revealed that the superhydrophobic coatings exhibited a freezing initiation temperature as low as-17.25℃.

关键词： Superhydrophobic coatings Anti-icing Mechanical durability

An integral method for calculation of capillary pressure based on centrifuge data of tight sandstone

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Petroleum Science 2022年第1期19卷 91-99页

作者： Wei Xu Hang Huang Shi-zhen Ke Jin-Peng li Hai-Feng Zhang Yu-Bo Hu Key Laboratory of Exploration Technology for Oil and Gas Resources of Ministry of Education Yangtze UniversityWuhanHubei 430100China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China School of Geosciences China University of PetroleumQingdaoShandong 266580China

The traditional Hassler-Brunner(HB)interpretation method of centrifuge capillary pressure is widely used in materials,soil,biotechnology,and especially in the petroleum ***,the assumptions of the traditional method cannot be simultaneously satisfied,the traditional method has been known to lead significant errors in some *** this paper,a new double integral method is proposed to evaluate the centrifuge capillary pressure of long tight sandstone *** the changes of capillary length and interface of wetting phase and non-wetting phase fluids are considered by the new integral method,thus the average pressure and saturation derived from the proposed double integral method is more sufficient in theoretic foundation and clearer on physical *** comparing with the measured capillary pressure of long tight sandstone core samples from porous plate,the capillary pressure calculated from traditional HB method is obviously smaller than the measured value,and the discrepancy increases with the decreasing core ***,the average capillary pressure obtained by the proposed double integral method is remarkably consistent with the measured *** findings of this study can help for better understanding of distribution of wetting phase fluid and average centrifuge capillary pressure in the core during centrifugal process.

关键词： Centrifuge method Capillary pressure Tight sandstone NMR Water saturation

Multiresponsive,easy-reversible,and dual-visual Pt(Ⅱ)salt nanostructures for advanced anti-counterfeiting application

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Nano Research 2024年第1期17卷 372-381页

作者： zhen Su§ Depeng li§ lixin Zhang Si Tian Yuhong Su xiaoyun Hu Duan Xiong Qingqing Guan Key Laboratory of Oil and Gas Fine Chemicals Ministry of Education College of Chemical EngineeringXinjiang UniversityUrumqi 830017China

Smart materials that integrate multi-stimuli response,full reversibility,and dual-visual read-out channel are highly desired for anticounterfeiting and information encryption ***,we developed a multiresponsive perchlorate terpyridyl Pt(Ⅱ)nano complex which could undergo fully reversible conversion between three forms stimulated by water or formaldehyde molecule due to the extent of Pt–Pt ***,a dual-visual channel,i.e.,the colorimetric channel changed from yellow to orange or red and the corresponding luminescent channel from orange to orange-red or red,has also been *** weak and equivalent strength of ion-dipole interaction and hydrogen bond that generated between formaldehyde/water and Pt(II)salt result in the easy-control reversibility between the three ***,by introducing different polymer matrices,1Cl·ClO_(4)@PMMA(1Cl·ClO_(4):[Pt(tpy)Cl]·ClO4,tpy:2,2':6',2''-terpyridine),PMMA:poly(methyl methacrylate))and 1Cl·ClO4@PVA(PVA:polyvinyl alcohol)are successfully constructed,which exhibit different reversible behaviors since the PMMA and PVA matrix exert different influences on the strength of *** smart Pt(II)salt nanostructures present great potential for high-security-level anticounterfeiting application.

关键词： Pt(II)complex multiresponse reversibility anticounterfeiting information encryption

Field synergy analysis of pollutant dispersion in street canyons and its optimization by adding wind catchers

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Building Simulation 2021年第2期14卷 391-405页

作者： Tingzhen Ming Huina Han zhen Zhao Renaud de Richter Yongjia Wu Wei li Nyuk Hien Wong School of Civil Engineering and Architecture Wuhan University of TechnologyNo.122 Luoshi RoadHongshan DistrictWuhan430070China School of Architectural Engineering Huanggang Normal UniversityNo.146 Xingang Second RoadHuanggang438000China School of design and environment National University of Singapore4 Architecture Drive117566SingaporeSingapore Tour-Solaire.Fr 8 Impasse des PapillonsF34090MontpellierFrance School of Engineering&Applied Science Aston UniversityBirminghamB47ETUK

The microenvironment,which involves pollutant dispersion of the urban street canyon,is critical to the health of pedestrians and *** objectives of this work are twofold:(i)to effectively assess the pollutant dispersion process based on a theory and(ii)to adopt an appropriate stratigy,i.e.,wind catcher,to alleviate the pollution in the street *** dispersion in street canyons is essentially a convective mass transfer *** the convective heat transfer process and the mass transfer process are physically similar and the applicability of field synergy theory to turbulence has been verified in the literature,we apply the field synergy theory to the study of pollutant dispersion in street *** this paper,a computational fluid dynamics(CFD)simulation is conducted to investigate the effects of wind catcher,wind speed and the geometry of the street canyons on pollutant *** to the field synergy theory,Sherwood number and field synergy number are used to quantitatively evaluate the wind catcher and wind speed on the diffusion of pollutants in asymmetric street *** results show that adding wind catchers can significantly improve the air quality of the step-down street canyon and reduce the average pollutant concentrations in the street canyon by 75%.Higher wind speed enhances diffusion of pollutants differently in different geometric street canyons.

关键词： street canyon field synergy theory CFD simulation pollutant dispersion wind catcher

Acoustics-Based Autonomous Docking for A Deep-Sea Resident ROV

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China Ocean Engineering 2022年第1期36卷 100-111页

作者： ZHANG Yun-xiu ZHANG Qi-feng ZHANG Ai-qun CHEN Jun li Xin-guo HE zhen State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China Key Laboratory of Marine Robotics Liaoning ProvinceShenyang 110169China University of Chinese Academy of Sciences Beijing 100049China Institutes of Deep-sea Science and Engineering Chinese Academy of SciencesSanya 100049China Institutes of Acoustics Chinese Academy of ScienceBeijing 100190China

This paper presents autonomous docking of an inhouse built resident Remotely Operated Vehicle(ROV),called Rover ROV,through acoustic guided techniques.A novel cage-type docking station has been *** docking station can be placed on a deep-sea lander,taking the Rover ROV to the *** of using vision-based pose estimation techniques and expensive navigation sensors,the Rover ROV docking adopts an ultra-short baseline(USBL)and low-cost inertial sensors to build an adaptive fault-tolerant integrated navigation *** solve the problem of sonar-based failure positioning,the measurement residuals are exploited to detect measurement ***,an adaptation scheme for estimating the statistical characteristics of noise in real-time is proposed,which can provide robust and smooth positioning *** is more suitable for a compact and low-cost deep-sea resident *** experiments have been conducted successfully in the Qiandao Lake and the South China Sea area with a depth of 3000 m,*** experimental results show that the functionality of autonomous docking has been *** the guidance of the navigation system,the Rover ROV can autonomously and efficiently return to the docking station within a range of 100 m even when the amounts of outliers exist in the acoustic positioning *** achievements can be applied to current ROVs by an easy retrofit.

关键词： resident ROV docking station autonomous docking acoustic guidance adaptive integrated navigation

Mechanical and Thermal Properties of Waterborne Polyurethane Films Modified by CaCO3@TiO2 Particles with UV Absorption Activity

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Chemical Research in Chinese Universities 2017年第6期33卷 1007-1011页

作者： JIANG Tiechao FAN Qingqiu HUANG Chunying li zhen GUO lijie ZHOU Bing China-Japan Union Hospital of Jilin University Changchun 130031 P. R. China College of Chemistry Jilin University Changchun 130021 P. R. China

CaCO3@TiO2 particles were synthesized through a direct carbonation method, which can be used as the substitutes of TiO2 in pigments and coatings. To improve the dispersion in waterborne polyurethane（WPU） suspensions, CaCO3@TiO2 particles were modified by stearic acid. SEM tests of the fractured surfaces of the composites films showed that the CaCO3@TiO2 particles were well embedded in the WPU matrix. And the mechanical properties, thermal stability and water resistance of the composites films were improved by the introduction of CaCO3@TiO2 particles.

关键词： Waterborne polyurethane CaCO3@TiO2 particle In situ polymerization

The damage to model concrete gravity dams subjected to water explosions

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Defence Technology（防务技术） 2023年第9期27卷 119-137页

作者： Shang Ma Ye-qing Chen zhen-qing Wang Shu-tao li Qing Zhu Long-ming Chen College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin150001China Institute of Defense Engineering AMSPLABeijing100036China

Over the past century,the safety of dams has gradually attracted attention from all *** on the dynamic response and damage evolution of dams under extreme loads is the basis of dam safety *** recent decades,scholars have studied the responses of dams under earthquake loads,but there is still much room for improvement in experimental and theoretical research on small probability loads such as *** this paper,a 50-m-high concrete gravity dam is used as a prototype dam,and a water explosion model test of a 2.5-m-high concrete gravity dam is *** water pressure and the acceleration response of the dam body in the test are *** pressure characteristics and dynamic response of the dam body are *** the dam damage test as an example,a numerical model of concrete gravity dam damage is established,and the damage evolution of the dam body is *** combining experiments and numerical simulations,the damage characteristics of the dam body under the action of different charge water explosions are *** integrity of the dam body is well maintained under the action of a small-quantity water explosion,and the dynamic response of the dam body is mainly caused by the shock *** the shock wave and the bubble pulsation cause the dam body to accelerate,and the peak acceleration of the dam body under the action of the bubble pulsation is only one percent of the peak acceleration of the dam body under the action of the shock *** subjected to explosions in large quantities of water,the dam body is seriously *** the action of a shock wave,the dam body produces a secondary acceleration response,which is generated by an internal interaction after the dam body is *** damage evolution process of the dam body under the action of a large-scale water explosion is analysed,and it is found that the shock wave pressure of the water explosion causes local damage to the dam body facing the ***

关键词： Underwater explosion Concrete gravity dam Model test Damage evolution

Influence of filler characteristics on particle removal in fluid catalytic cracking slurry under an alternating electric field

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Petroleum Science 2024年第3期21卷 2102-2111页

作者： Qiang li Hui-zhen Yang Can Yang Qing-Zhu Qiu Wei-Wei Xu Zhao-Zeng liu College of New Energy China University of Petroleum(East China)Qingdao266580ShandongChina

The characteristics of the packing material under an alternating electric field are an important factor in the removal of FCCS *** this study,the electric field distribution of a separation unit consisting of packed spheres under an alternating electric field is simulated,and the movement mechanism of catalyst particles is ***"effective contact point"model is derived to predict the adsorption of filler contact points on catalyst particles under the alternating electric field,and the model is validated by simulations and *** numerical calculation and experimental results indicate that the electrical properties of the filler spheres,the filler angleθ,and the frequency f of the alternating electric field affect the adsorption of catalyst *** the frequency of the electric field increases,the particle removal efficiency of the high-conductivity filler(silicon carbide)increases and then settles,and the separation efficiency of the low-conductivity filler(glass,zirconia)is not sensitive to the change in electric field frequency.

关键词： Fluid catalyticcracking slurry(FCCS) Particle AC electric field Fillers Removal