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苎麻表面接枝改性及其对苎麻纤维增强环氧复合材料力学性能与界面性能的影响研究（英文）

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2019年第9期20卷 660-674页

作者： Anna DILFI KF Zi-jin CHE Gui-jun XIAN Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of TechnologyHarbin150090China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology Harbin Institute of TechnologyHarbin150090China School of Civil Engineering Harbin Institute of TechnologyHarbin150090China

目的:通过在苎麻纤维表面接枝纳米二氧化硅颗粒,改善苎麻纤维与环氧树脂的界面粘结性能,从而提升苎麻纤维增强环氧树脂复合材料的力学性能。创新点:将纳米二氧化硅颗粒接枝到苎麻纤维表面,从而大幅提升苎麻纤维与环氧树脂的界面粘结性... 详细信息

目的:通过在苎麻纤维表面接枝纳米二氧化硅颗粒,改善苎麻纤维与环氧树脂的界面粘结性能,从而提升苎麻纤维增强环氧树脂复合材料的力学性能。创新点:将纳米二氧化硅颗粒接枝到苎麻纤维表面,从而大幅提升苎麻纤维与环氧树脂的界面粘结性能与复合材料的力学性能。方法:利用十二烷基硫酸钠均匀分散二氧化硅纳米粒子,并在硅烷偶联剂作用下,将二氧化硅纳米粒子接枝到苎麻纤维表面。结论:纳米二氧化硅接枝到苎麻纤维表面大幅提升了纤维表面粗糙度,降低了纤维亲水性能,升高了纤维与环氧树脂的界面粘度,从而改善了复合材料的力学性能。

关键词：纳米二氧化硅十二烷基硫酸硅烷偶联剂苎麻纤维力学性能界面性能

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Damage detection in metallic plates using d36 piezoelectric phased arrays 8

Damage detection in metallic plates using d36 piezoelectric ...

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8th European Workshop on Structural Health Monitoring, EWSHM 2016

作者： Wang, Wentao Lynch, Jerome P. Li, Hui Key Lab of Structures Dynamic Behavior and Control Ministry of Education Harbin Institute of Technology Harbin150090 China Department of Civil and Environmental Engineering University of Michigan Ann ArborMI48109-2125 United States Department of Electrical Engineering and Computer Science University of Michigan Ann ArborMI48109-2125 United States

ISBN: (纸本)9781510827936

Recently, d36-type piezoelectric wafers derived from lead magnesium niobate-lead titanate (PMN-PT) single crystal materials have been proposed for elastic wave generation in thinwalled structures. In contrast to traditional d31 piezoelectric materials which generate symmetric and anti-symmetric Lamb waves, d36 introduces these same Lamb waves plus an inplane shear horizontal (SH) wave. Based on guided wave theory, the SH0 wave mode is nondispersive which may find many advantages uses in structural health monitoring. To detect and localize damage (e.g., cracks, corrosion) in thin walled structures, a phased array of d36- type piezoelectric wafers is proposed. To validate the proposed phase array, extensive experiments have been conducted using an aluminum plate with four d36 PMN-PT piezoelectric wafers surface bonded. The d36 phased array is shown capable of accurately detecting the location of local damage in the plate. Good detection accuracy is observed indicating that this proposed methodology has the potential to provide an effective identification of damage in metallic thin walled structures.

关键词： Damage detection

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Corrigendum to “Predicting water permeability and relative gas permeability of unsaturated cement-based material from hydraulic diffusivity” [Cem. Concr. Res. 58 (2014) 152–1 60]

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Cement and Concrete Research 2016年 87卷 105-106页

作者： Chunsheng Zhou Key Lab of Structures Dynamic Behavior and Control (Harbin Institute of Technology) Ministry of Education Heilongjiang Harbin 150090 China School of Civil Engineering Harbin Institute of Technology Harbin 150090 China

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Mechanical properties of steel fiber-reinforced reactive powder concrete at high temperature and after cooling

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Procedia Engineering 2017年 210卷 597-604页

作者： Muhammad Abid Xiaomeng Hou Wenzhong Zheng Ghulam Qadir Waqar Key Lab of Structures Dynamic Behavior and Control Ministry of Education Harbin Institute of Technology Harbin 150090 China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology Harbin Institute of Technology Harbin 150090 China

Reactive powder concrete (RPC) is advanced cement-based material. It is produced through microstructure enhancement technique. Like other types of concretes, RPC has also been affected by severe environmental conditions such as accidental fire. Up to date, very limited research has been carried out to compare the performance of RPC at fire and after cooling. To address this gap in knowledge, the mechanical properties such as compressive strength, split-tensile strength, flexural strength and elastic modulus have been studied at high temperature and after cooling. 72 cubic specimens and 72 prismatic samples were tested. The hot and residual strength results were plotted as a function of temperature. The results indicated a higher residual strength than hot-strength in the temperature range of 20-300℃. Above 300℃, there was no sizable difference between the hot and residual strength of PRC. A comparison has also been made among the test data with current design codes.

关键词： Reactive powder concrete high temperature hot behavior residual behavior mechanical properties

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Study on the effect of the strength grade on the creep behavior of concrete

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Open Civil Engineering Journal 2015年第1期9卷 881-887页

作者： Wenzhong, Zheng Can, Tang School of Civil Engineering Harbin Institute of Technology Harbin Heilongjiang150090 China Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of Technology Harbin Heilongjiang150090 China

The internal factors which influenced the concrete creep behavior have been mostly divided by the creep model at home and abroad, but the computing is complex. In order to directly use the creep model in engineering conveniently, it is necessary to consider the effect of concrete strength grade on concrete creep. 302 creep test data with a loading age of 28 d, a lasting age of 360 d, and meet certain environmental conditions were collected. The strength of prism with different aspect ratio and high ratio of cylinder specimen was equivalent to the standard cube strength. The relationship between the creep compliance and creep degree and the cube compressive strength of concrete was fitted, and influence coefficient of the strength grade on the creep degree and creep coefficient were obtained. The influence coefficient can be used to determine creep value, creep coefficient, creep degree of concrete. In this paper, the effect of the strength grade on creep was considered directly, which involves the cube compressive strength of concrete from 15 MPa to 180MPa. The research results can be used in broad scope and has certain practical value.. © 2015, Wenzhong and Can;Licensee Bentham Open.

关键词： Creep

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Evaluation of residual mechanical properties of steel fiber-reinforced reactive powder concrete after exposure to high temperature using nondestructive testing

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Procedia Engineering 2017年 210卷 588-596页

作者： Xiaomeng Hou Muhammad Abid Wenzhong Zheng Ghulam Qadir Waqar Key Lab of Structures Dynamic Behavior and Control Ministry of Education Harbin Institute of Technology Harbin 150090 China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology Harbin Institute of Technology Harbin 150090 China

Reactive powder concrete (RPC) is classified as ultra-high performance concrete, owing to its superior strength, excellent durability and high fracture energy. However, RPC may also be severely affected by devastating fire exposures. This paper presents the variations in residual mechanical properties of RPC after exposure to high temperature. The strength of RPC after cooling was also assessed by nondestructive tests (NDTs). The ultrasonic pulse velocity (UPV) method and resonance frequency (RF) method were used. The samples were subjected to the target temperature of 120℃, 300℃, 500℃, 700℃ and 900℃. The heating was continued for further 3 hours so that steady state condition was achieved. The availab.e equations have been used for determination of dynamic elastic modulus of RPC using UPV and RF measurements. The residual mechanical properties, RF and UPV were plotted as a function of temperature. The result shows that the residual strength increases from room temperature to 300℃. However, above 300℃, it’s decreasing gradually. Various comparisons have been made between residual mechanical strength versus UPV and RF measurements. Relationships have been proposed among residual mechanical properties versus NDTs values. These relationships can be employed for post-fire strength assessment of RPC structures.

关键词： Reactive powder concrete high temperature residual mechanical properties ultrasonic pulse velocity resonance frequency

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Water transport properties for unsaturated cement-based materials

Water transport properties for unsaturated cement-based mate...

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第三届中国国际复合材料科技大会

作者： Chunsheng Zhou Wei Wang Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of Technology Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry and Information Technology Harbin Institute of Technology

The durability performance of cement-based material is actually and mostly determined by the penetration process of deleterious agents and possible chemical and physical reactions between them, where water always plays an important role. In addition, the transport properties of other agents also depend seriously on the water content. It is rather essential to understand the distribution of water and its transport in partially saturated cement-based materials, which are facilitated herein through low-field nuclear magnetic resonance(NMR) technique and gas permeability testing on partially saturated white cement mortar specimens. It is found that most water is stored in inter-layer pores when it is equilibrated with relative humidity below 75%. Due to the marked contraction or swelling of interlayer pores during drying or wetting, the gel pores and inter-hydrate pores are greatly changed while the overall porosity is little altered. At totally drying state, the pore structure of cement-based material becomes obviously coarser, making the gas permeability remarkably larger than water permeability by as large as 2-3 orders of magnitudes. The intrinsic gas permeability obtained on partially saturated specimens reveals that, both the permeability to water and gas depend nonlinearly on the water content, which are well characterized by the models we suggested. Not only the water saturation degree but also the induced pore structure evolution should be incorporated when modelling the transport of water.

关键词： Durability permeability pore structure saturation degree low-field NMR

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Ordered mesoporous carbon as an efficient heterogeneous catalyst to activate peroxydisulfate for degradation of sulfadiazine

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Chinese Chemical Letters 2022年第5期33卷 2747-2752页

作者： Zhi-Ling Li Di Cao Hao Cheng Fan Chen Jun Nan Bin Liang Kai Sun Cong Huang Ai-Jie Wang State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China School of Civil&Environmental Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China School of Ecology and Environment Northwestern Polytechnical UniversityXi’an 710129China Key Lab of Structures Dynamic Behavior and Control of China Ministry of Education School of Civil EngineeringHarbin Institute of TechnologyHarbin 150090China National Technology Innovation Center of Synthetic Biology Tianjin Institute of Industrial BiotechnologyChinese Academy of SciencesTianjin 300308China

Catalytic potential of carbon nanomaterials in peroxydisulfate(PDS)advanced oxidation systems for degradation of antibiotics remains poorly *** study revealed ordered mesoporous carbon(type CMK)acted as a superior catalyst for heterogeneous degradation of sulfadiazine(SDZ)in PDS sys-tem,with a first-order reaction kinetic constant(k)and total organic carbon(TOC)mineralization efficiency of 0.06 min^(–1) and 59.67%±3.4%within 60min,*** catalyzed PDS system exhibited high degradation efficiencies of five other sulfonamides and three other types of antibiotics,verifying the broad-degradation capacity of *** neutral pH conditions,the optimal catalytic parameters were an initial SDZ concentration of 44.0mg/L,CMK dosage of 0.07g/L,and PDS dosage of 5.44mmol/L,respectively.X-ray photoelectron spectroscopy and Raman spectrum analysis confirmed that the defect structure at edge of CMK and oxygen-containing functional groups on surface of CMK were major active sites,contributing to the high catalytic *** radical quenching analysis revealed that both SO_(4)•−and•OH were generated and participated in catalytic *** addition,direct electron transfer by CMK to activate PDS also occurred,further promoting catalytic *** of SDZ molecule was optimized using density functional theory,and the possible reaction sites in SDZ molecule were calculated using Fukui *** ultra-high-performance liquid chromatography(UPLC)–mass spectrometry(MS)/MS analysis,three potential degradation pathways were proposed,including the direct removal of SO_(2)molecules,the 14S-17N fracture,and the 19C-20N and 19C-27N cleavage of the SDZ *** study demonstrated that ordered mesoporous carbon could work as a feasible catalytic material for PDS advanced oxidation during removal of antibiotics from wastewater.

关键词： Ordered mesoporous carbon CMK Sulfadiazine Peroxydisulfate Degradation pathway Density functional theory Physicochemical properties

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Creep of concrete with high amounts of supplementary cementitious materials and applications in concrete-filled tubes 4

Creep of concrete with high amounts of supplementary cementi...

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4th International Conference on Sustainable Construction Materials and Technologies, SCMT 2016

作者： Kuder, Katie Lehman, Dawn Chien, Jie Roeder, Charles Lowes, Laura Civil and Environmental Engineering Seattle University 901 12th Ave SeattleWA98122-1090 United States More Hall Civil and Environmental Engineering University of Washington SeattleWA98195-2700 United States Key Lab of Structures Dynamic Behavior Control of the Ministry of Education Harbin Institute of Technology Harbin150090 China

Due to its design versatility, availab.lity and cost efficiency, concrete continues to play a dominant role in the construction industry. However, the production of Portland cement, a primary component of typical concrete mixes, is known to have a serious impact on the environment. Increasing the use of supplementary cementitious materials (SCMs) in concrete is an obvious and necessary step to reduce the carbon emissions associated with cement production. However, most reinforced concrete (including cast-in-place and precast) structural components rely on the early stiffness and strength of the concrete to resist self-weight and construction loadings after the release of the formwork. In contrast to cement-only concretes, high SCM concretes require more time to reach the target strength and stiffness values. Therefore, a structural component that does not depend on these engineering properties during construction is preferred. Concrete-filled tubes (CFTs) offer a solution to this challenge, with the steel tube is able to support construction loads while the high SCM concrete fill develops its strength and stiffness. However, there are concerns about the long-term deformations (creep) of high SCM concrete and its impact on CFT performance. This research develops models to predict the long-term (creep) response of SCM concretes and uses those predictive models to assess the long-term response of CFTs with SCM concrete fill. The models were validated using a large SCM database and two full-scale CFTs with SCM concrete fill that were tested under sustained loading. © 2016 International Committee of the SCMT conferences. All rights reserved.

关键词： Creep

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Defect-Mediated Work Function Regulation in Graphene Film for High-Performing Triboelectric Nanogenerators

SSRN

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SSRN 2022年

作者： Zhou, Jian Zhang, Jianing Deng, Yuanpeng Zhao, Han Zhang, Pengyu Fu, Shubing Xu, Xiang Li, Hui Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters The Ministry of Industry and Information Technology Key Lab of Structures Dynamic Behavior and Control The Ministry of Education Harbin Institute of Technology Harbin150090 China

Triboelectric nanogenerators (TENGs) demonstrate an attractive pathway to directly convert broadband mechanical energy into electrical energy for a green and clean energy source. Triboelectric material design with tailored work function has played a critical role in enhancing the output performance of TENGs. However, regulating the work function of triboelectric materials still remains challenging due to the limited particle/group/ion doping rate. Here, we reported a simple defect-mediated strategy (DMS) to regulate the work function in graphene film as the positive triboelectric material by different contents of oxygen and carbon defects derived at annealing temperatures from 500 ºC to 3000 ºC. Our DMS features a continuous and wide-range tunable work function from 4.680 eV to 4.479 eV, and the as-assembled TENGs produce output voltages and currents up to 190 V and 14 μA, respectively. The efficient work function regulation of this type establishes a set of fundamental considerations in triboelectric material design, especially the two-dimensional materials, to enhance the energy harvesting and sensing performances of TENGs. © 2022, The Authors. All rights reserved.

关键词： Nanogenerators

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