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Article
Publication date: 3 January 2017

Yingjun Zhang, Yawei Shao, Qiumei Shi, Yanqiu Wang, Guozhe Meng and Ping Li

The purpose of this paper was to research the influence of polyaniline/montmorillonite (PANI/OMMT) composite powder content on the corrosion protection of epoxy (EP) coating.

Abstract

Purpose

The purpose of this paper was to research the influence of polyaniline/montmorillonite (PANI/OMMT) composite powder content on the corrosion protection of epoxy (EP) coating.

Design/methodology/approach

The polyaniline/montmorillonite/epoxy (PANI/OMMT/EP) coatings containing different contents of PANI/OMMT composite powder were prepared on steel. The corrosion protection performances of PANI/OMMT/EP coatings in 3.5 per cent NaCl solutions were investigated by electrochemical impedance spectroscopy. The barrier property of coatings was examined using water absorption analysis. The structure and crosslink density of coatings were examined using scanning electron microscopy and differential scanning calorimetry, respectively.

Findings

The PANI/OMMT composite powder could enhance the barrier properties of the EP coating and reduce the corrosion rate of the steel beneath the coating. The coating showed the best corrosion protection performance when 3 per cent PANI/OMMT powder was added to the coating.

Originality/value

The research clarified the influence of PANI/OMMT content on the corrosion protection of coating from two aspects: one is the barrier performance of the coating; the other is the corrosion inhibitors for metal substrate.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 1
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 21 September 2018

Yingjun Zhang, Baojie Dou, Yawei Shao, Xue-Jun Cui, Yanqiu Wang, Guozhe Meng and Xiu-Zhou Lin

This paper aim to investigate the influence of PA on the corrosion behavior of carbon steel with blast cleaned or pre-rusted treatments, and interpret the inhibition…

Abstract

Purpose

This paper aim to investigate the influence of PA on the corrosion behavior of carbon steel with blast cleaned or pre-rusted treatments, and interpret the inhibition mechanism of PA on the steel with different surface treatments.

Design/methodology/approach

The influence of PA on the corrosion behavior of blast cleaned or rusty steel was investigated by means of electrochemical impedance spectroscopy (EIS). The EIS data were analyzed using the @ZsimpWin commercial software. The morphology and component of steel after immersion were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), Fourier transformation infrared (FTIR) and X-ray diffractometer (XRD).

Findings

EIS analysis results indicated that PA had good corrosion inhibition for blast cleaned or rusty steel. SEM, EDS, FTIR and XRD further indicated that PA had two main corrosion inhibition processes for the corrosion inhibition of blast cleaned or rusty steel: corrosion dissolution and formation of protective barrier layers.

Originality/value

Most published works focus the attention only toward the effect of corrosion inhibitor for the clean metal surfaces. However, the surface condition of metal sometimes is unsatisfactory in the practical application of corrosion inhibitor, such as existing residual rust. Some studies also have shown that several corrosion inhibitors could be applied on partially rusted substrates. These inhibitors mainly include tannins and phosphoric acid, but not PA. Therefore, the authors investigated the influence of PA on the corrosion behavior of carbon steel with blast cleaned or pre-rusted treatments in this paper.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 6
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 29 November 2018

Yingjun Zhang, Xue-Jun Cui, Yawei Shao, Yanqiu Wang, Guozhe Meng, Xiu-Zhou Lin, Dongquan Zhong and Dajian Wang

This paper aims to prepare a residual rust epoxy coating by adding different quantities of phytic acid (PA) on the surface of the rusty steel and investigate the corrosion…

Abstract

Purpose

This paper aims to prepare a residual rust epoxy coating by adding different quantities of phytic acid (PA) on the surface of the rusty steel and investigate the corrosion protection of PA and its action mechanisms.

Design/methodology/approach

A residual rust epoxy coating by adding different quantities of PA was prepared on the surface of the rusty steel. The influence of PA on the corrosion resistance of epoxy-coated rusty steel was investigated by means of electrochemical impedance spectroscopy and adhesion testing.

Findings

Results indicated that PA can substantially improve the corrosion resistance of epoxy-coated rusty steel. This improvement is due to the reaction of PA with residual rust and generation of new compounds with protection properties and increased adhesive strength effects on the coating/metal interface. The coating showed better protection performance when 2 per cent PA was added.

Originality/value

Considering the structure of the active groups, PA has strong chelating capability with many metal ions and can form stable complex compounds on the surface of a metal substrate, thereby improving corrosion resistance. In recent years, PA has been reported to be useful in the conversion of coatings or as green corrosion inhibitor. To the best of the authors’ knowledge, few studies have reported the use of PA as a rust converter or residual rust coating. The present work aims to improve the corrosion resistance of residual rust epoxy coating by adding PA.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 2
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 19 January 2015

Wen Liu, Yingjun Zhang, Xuefeng Yang and Shengwei Xing

The aim of this article is to present a PIN (pedestrian inertial navigation) solution that incorporates altitude error correction, which eliminates the altitude error…

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Abstract

Purpose

The aim of this article is to present a PIN (pedestrian inertial navigation) solution that incorporates altitude error correction, which eliminates the altitude error accurately without using external sensors. The main problem of PIN is the accumulation of positioning errors due to the drift caused by the noise in the sensors. Experiment results show that the altitude errors are significant when navigating in multilayer buildings, which always lead to localization to incorrect floors.

Design/methodology/approach

The PIN proposed is implemented over an inertial navigation systems (INS) framework and a foot-mounted IMU. The altitude error correction idea is identifying the most probable floor of each horizontal walking motion. To recognize gait types, the walking motion is described with angular rate measured by IMU, and the dynamic time warping algorithm is used to cope with the different dimension samples due to the randomness of walking motion. After gait recognition, the altitude estimated with INS of each horizontal walking is checked for association with one of the existing in a database.

Findings

Experiment results show that high accuracy altitude is achieved with altitude errors below 5 centimeters for upstairs and downstairs routes in a five floors building.

Research limitations/implications

The main limitations of the study is the assumption that accuracy floor altitude information is available.

Originality/value

Our PIN system eliminates altitude errors accurately and intelligently, which benefits from the new idea of combination of gait recognition and map-matching. In addition, only one IMU is used which is different from other approach that use external sensors.

Details

Sensor Review, vol. 35 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 6 August 2019

Jingrong Li, Zhijia Xu, Qinghui Wang, Guanghua Hu and Yingjun Wang

The three-dimensional porous scaffold is an important concept in tissue engineering and helps to restore or regenerate a damaged tissue. Additive manufacturing (AM…

Abstract

Purpose

The three-dimensional porous scaffold is an important concept in tissue engineering and helps to restore or regenerate a damaged tissue. Additive manufacturing (AM) technology makes the production of custom-designed scaffolds possible. However, modeling scaffolds with intricate architecture and customized pore size and spatial distribution presents a challenge. This paper aims to achieve coupling control of pore size and spatial distribution in bone scaffolds for AM.

Design/methodology/approach

First, the proposed method assumes that pore size and spatial distribution have already been transformed from the requirements of scaffolds as inputs. Second, the structural characteristics of scaffolds are explicitly correlated with an all-hexahedron meshing method for scaffold design so that the average pore size could be controlled. Third, the highly coupled internal mesh vertices are adjusted based on a random strategy so that the pore size and spatial distribution conform to their respective desired values. Fourth, after the adjustment, the unit pore cell based on a triply periodic minimal surface was mapped into the hexahedrons through a shape function, thereby ensuring the interconnectivity of the porous scaffold.

Findings

The case studies of three bone scaffolds demonstrate that the proposed approach is feasible and effective to simultaneously control pore size and spatial distribution in porous scaffolds.

Practical implications

The proposed method may make it more flexible to design scaffolds with controllable internal pore architecture for AM.

Originality/value

In the control approach, the highly coupled mesh vertices are adjusted through a random strategy, which can determine the moving direction and range of a vertex dynamically and biasedly, thus ensuring the feasibility and efficiency of the proposed method.

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Article
Publication date: 12 July 2013

Jiaolong Li, Yingjun Chu, Mingyue Lin, Jianya Zhang and Jingjing Yang

Twenty-two coal samples and eleven parting samples were taken from Gashun Coal Mine, Hoxtolgay coalfield, Xingjiang Autonomous Region, and the samples were analyzed by…

Abstract

Twenty-two coal samples and eleven parting samples were taken from Gashun Coal Mine, Hoxtolgay coalfield, Xingjiang Autonomous Region, and the samples were analyzed by using optical microscopy. The results indicate that the dominant macerals are vitrinite (av. 76.6%) with minor amounts of inertinite (av. 18.84%) and low liptinite (av. 2.7%), along with low content of mineral matters (av. 1.86%). All GI, TPI, VI, GWI values and two facies diagrams indicate that the main coal facies are in limnic area. Meanwhile, the overall petrographic composition and coal facies types indicate that the coal formed in strong wet reducing peat accumulating conditions which were the lacustrine marshes.

Details

World Journal of Engineering, vol. 10 no. 3
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 20 February 2014

Zhiqiang Meng, Yingjun Chu, Zijian Zhang and Xiaolong Tian

Cobalt is an extremely useful element, but there are very few separate cobalt deposits in China and imported cobalt ores are usually toxic. In order to develop more…

Abstract

Cobalt is an extremely useful element, but there are very few separate cobalt deposits in China and imported cobalt ores are usually toxic. In order to develop more low-toxicity cobalt resources, China has to encourage exploration and development of this element. Samples are taken from Hanxing iron ore tailings and analyzed by ICP-MS and barium chloride titration experiments. The results indicate that the cobalt content is relatively high in Hanxing iron ore tailings, and some exceed the industrial grade. Therefore, with the depletion of cobalt resources, iron ore tailings are bound to become an important resource in China, and as these tailings are abundant in the Hanxing area, this area is expected to be of high development value.

Details

World Journal of Engineering, vol. 10 no. 6
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 6 February 2017

Shijiu Yin, Mo Chen, Yingjun Xu and Yusheng Chen

Unlike some developed countries, Chinese food safety certification system is multi-level including organic/green/hazard-free certifications. The purpose of this paper is…

Abstract

Purpose

Unlike some developed countries, Chinese food safety certification system is multi-level including organic/green/hazard-free certifications. The purpose of this paper is to assess consumers’ preferences for tomatoes carrying these different labels.

Design/methodology/approach

Data used in this study came from choice experiments (CEs) conducted in Shandong province, China. Based on experiment data, a random parameter logit model was established to analyze consumers’ willingness-to-pay (WTP).

Findings

Consumers’ WTP for organic tomatoes was higher than that for hazard-free and green-certified tomatoes. Furthermore, consumers’ WTP for the European Union (EU) organic label was higher than that for the Chinese organic label, whereas a non-significant difference existed between the levels of consumers’ WTP for hazard-free and green-certified tomatoes. Consumers with different food safety risk perception (FSRP) had large differences in WTP, whereas those with varying environmental awareness (ENAW) had similar levels of WTP.

Originality/value

This contribution is the first research which focuses on consumers’ WTP for EU organic label, Chinese organic label, green label, or hazard-free label on tomato through CEs in China. Furthermore, the influence of consumers’ FSRP and ENAW on their preference was analyzed through a random parameter logit model.

Details

China Agricultural Economic Review, vol. 9 no. 1
Type: Research Article
ISSN: 1756-137X

Keywords

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Article
Publication date: 5 June 2017

Shijiu Yin, Ying Li, Yingjun Xu, Mo Chen and Yiqin Wang

The purpose of this paper is to provide a basis for government decision makers regarding the gradual popularisation of traceable infant milk formula (IMF) and the…

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1099

Abstract

Purpose

The purpose of this paper is to provide a basis for government decision makers regarding the gradual popularisation of traceable infant milk formula (IMF) and the construction of a safe food market system.

Design/methodology/approach

The data were collected from 1,225 randomly selected consumers in Shandong Province, China using a choice experiment. The authors used the mixed logit model to determine consumer willingness to pay (WTP) for IMF profiles with different levels of five attributes: traceability information, brand, country of origin, place of sale and price.

Findings

Results indicated that traceability information was more important than brand or country of origin for Chinese consumers. In terms of WTP for different levels of traceability information, grazing information was the most preferred by the respondents. The order of preference with regards to country of origin and brand attributes suggests that consumers prefer “foreign milk powder” to domestic products. The difference in consumer WTP between IMF sold in drugstores and in supermarkets is minimal. The higher the food safety risk perception, the higher the WTP for traceability information and the higher the WTP for “foreign milk powder (brand or country of origin)” compared with domestic products. In addition, the differences in the WTP of various risk perception groups between IMF sold in drugstores and in supermarkets are minimal.

Originality/value

This study subdivides traceability information into three levels (i.e. cow grazing, IMF producing and IMF selling) based on supply chain processes. It then compares consumer preference for the traceability information attribute with those of other attributes, such as brand, country of origin and place of sale. This research is valuable to members of the academe, policy makers and food suppliers.

Details

British Food Journal, vol. 119 no. 6
Type: Research Article
ISSN: 0007-070X

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Article
Publication date: 20 April 2015

Yixiong Wei, Qifu Wang, Yunbao Huang, Yingjun Wang and Zhaohui Xia

The purpose of this paper is to present a novel strategy used for acceleration of free-vibration analysis, in which the hierarchical matrices structure and Compute Unified…

Abstract

Purpose

The purpose of this paper is to present a novel strategy used for acceleration of free-vibration analysis, in which the hierarchical matrices structure and Compute Unified Device Architecture (CUDA) platform is applied to improve the performance of the traditional dual reciprocity boundary element method (DRBEM).

Design/methodology/approach

The DRBEM is applied in forming integral equation to reduce complexity. In the procedure of optimization computation, ℋ-Matrices are introduced by applying adaptive cross-approximation method. At the same time, this paper proposes a high-efficiency parallel algorithm using CUDA and the counterpart of the serial effective algorithm in ℋ-Matrices for inverse arithmetic operation.

Findings

The analysis for free-vibration could achieve impressive time and space efficiency by introducing hierarchical matrices technique. Although the serial algorithm based on ℋ-Matrices could obtain fair performance for complex inversion operation, the CUDA parallel algorithm would further double the efficiency. Without much loss in accuracy according to the examination of the numerical example, the relative error appeared in approximation process can be fixed by increasing degrees of freedoms or introducing certain amount of internal points.

Originality/value

The paper proposes a novel effective strategy to improve computational efficiency and decrease memory consumption of free-vibration problems. ℋ-Matrices structure and parallel operation based on CUDA are introduced in traditional DRBEM.

Details

Engineering Computations, vol. 32 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

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