Guirong Yang, Wenming Song, Zibo Zhu, Ying Ma and Yuan Hao
The paper aims to study the effect of liquid flow velocity on corrosion behavior of 20# steel at initial stage under (CO2/aqueous solution) gas–liquid two-phase plug flow…
Abstract
Purpose
The paper aims to study the effect of liquid flow velocity on corrosion behavior of 20# steel at initial stage under (CO2/aqueous solution) gas–liquid two-phase plug flow conditions.
Design/methodology/approach
Weight loss, scanning electron microscopy, energy-dispersive X-ray spectroscopy and XPS methods were used in this study.
Findings
The corrosion rate increased with the increasing liquid flow velocity at any different corrosion time. The corrosion rate decreased with the extension of corrosion time at the same liquid flow velocity. There was no continuous corrosion products film on the whole pipe wall at any different corrosion time. The macroscopic brown-yellow corrosion products on the pipe wall surface decreased with the increasing liquid flow velocity and the loose floccus corrosion products decreased gradually until these products were transformed into un-continuous needle-like dense products with the increasing liquid velocity. The main elements among the products film were Fe, C and O, and the main phases of products film on the pipe wall were Fe3C, FeCO3, FeOOH and Fe3O4. When the corrosion time was 1 h under different liquid–velocity condition, the thickness of local corrosion products film was from 3.5 to 3.8 µm.
Originality/value
The ion mass transfer model of corrosion process in pipe was put forward under gas–liquid two-phase plug flow condition. The total thickness of diffusion sublayer and turbulence sublayer decreased as well as the turbulence propagation coefficient increased with the increasing liquid velocity, which led to the increasing velocity of ion transfer during corrosion process. This was the fundamental reason for the increase of corrosion rate with the increasing liquid velocity.
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Guirong Yang, Wenming Song, Fuqiang Wang, Ying Ma and Yuan Hao
This paper aims to investigate the corrosion rate, surface morphology and composition of corrosion products of 20# seamless steel in aqueous CO2 solution under stratified…
Abstract
Purpose
This paper aims to investigate the corrosion rate, surface morphology and composition of corrosion products of 20# seamless steel in aqueous CO2 solution under stratified gas-liquid two-phase flow condition. The development of a corrosion products layer has also been discussed.
Design/methodology/approach
The following methods were used: weight loss method, scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction.
Findings
The corrosion rate curve presents an irregular zigzag change trend with a gradual increase in time. The peak value of the corrosion rate appears when the corrosion time is 4 h and 8 h. The corrosion products layer is composed of two sub-layers: the inner dense layer that is about 6 µm thick and the outer loose layer that is about 9 µm thick when the corrosion time is 8 h. The main corrosion product are FeCO3 and Fe2O3.
Originality/value
The atomic ratio of Fe/C/O is relatively stable for the inner dense layer, but changes in thickness for the outer loose layer. There is a densification stage after a loose corrosion products layer forms, and it is periodic.
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Guirong Yang, Zhaoxia Pan, Zhenghai Zhang, Wenming Song, Ying Ma and Yuan Hao
This study aims to investigate the initial corrosion behavior in aqueous solution of 20# seamless steel under (CO2/aqueous solution) gas–liquid two-phase stratified flow…
Abstract
Purpose
This study aims to investigate the initial corrosion behavior in aqueous solution of 20# seamless steel under (CO2/aqueous solution) gas–liquid two-phase stratified flow conditions.
Design/methodology/approach
The initial corrosion behavior was studied through the weight loss methods, scanning electron microscopy with energy-dispersive x-ray spectroscopy and x-ray diffraction.
Findings
The corrosion rate of 20# steel obviously increases with the increasing gas pressure at different corrosion time when the CO2 pressure is less than 0.11 MPa, and the increase of corrosion rate tends to be steady when the pressure exceeds 0.11 MPa. With the increase of CO2 pressure, the corrosion products changed from flocculent to acicular, granular and scaly. A four-stage model for the growth of the corrosion product layer was proposed, namely, the diffusion reaction stage, the local film formation stage, the complete film formation stage and the densification stage of the product film.
Originality/value
A four-stage model for the growth of the corrosion product layer on the pipe wall surface under this condition was proposed, namely, the diffusion reaction stage, the local film formation stage, the complete film formation stage and the densification stage of the product film. The growing process and densification mechanism of corrosion products layer were discussed.
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Thi Tuan Linh Pham, Hao-Yuan Chang, Alice May-Kuem Wong, Vu Hong Van and Ching-I Teng
Nurses' health is vital for retaining nurses in the profession. However, lack of study has examined how headaches and professional commitment interact to impact professional…
Abstract
Purpose
Nurses' health is vital for retaining nurses in the profession. However, lack of study has examined how headaches and professional commitment interact to impact professional turnover intention. This study aims to examine the moderating effect of nurses' headaches on the relationship among professional commitment factors (affective professional commitment, continuance professional commitment and normative professional commitment) and nurses' professional turnover intention.
Design/methodology/approach
This study employed a two-wave design and questionnaires to survey 524 nurses from a large medical center in Taiwan during February and March 2017 (the first wave) and June and August 2017 (the second wave). Headaches were measured using descriptions formulated by the International Headache Society. Items measuring other constructs came from relevant literature. Regression analysis was used to assess relationships between the constructs.
Findings
All aspects of professional commitment are negatively related to professional turnover intention (B [CI] = −0.47 [−0.58, −0.36], −0.20 [−0.29, −0.11], −0.22 [−0.32, −0.12], p < 0.001). Headaches reduce the negative relation between affective professional commitment and professional turnover intention (B [CI] = 0.14 [0.02,0.27], p = 0.02).
Practical implications
Headaches could interfere with nurses' commitment to the nursing profession and influence nurses' intention to leave. Managers should seek means to help alleviate nurses' headaches.
Originality/value
This study is the first to examine how headaches and professional commitment interact to influence nurses' professional turnover intention.
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Hongping Yuan, Liyin Shen and Jiayuan Wang
The generation of construction and demolition waste in China is a pressing need to be minimized in order to alleviate the environmental burden. The effectiveness of implementing…
Abstract
Purpose
The generation of construction and demolition waste in China is a pressing need to be minimized in order to alleviate the environmental burden. The effectiveness of implementing construction and demolition waste management in this economy, however, is very limited due to various barriers. Therefore, this paper aims to explore the major obstacles to managing construction and demolition waste in China.
Design/methodology/approach
The views from Chinese practitioners were collected via a questionnaire survey. The respondents were invited to rate a total of 16 obstacles that hinder the effective implementation of construction and demolition waste management as gleaned from previous literature and six semi‐structured interviews. The results of the questionnaire were analyzed by ranking analysis and factor analysis.
Findings
The findings show that “lack of a well‐developed waste recycling market”, “insufficient regulation support” and “waste reduction does not receive sufficient attention in construction design” are perceived as the three barriers of most importance. Furthermore, the 16 obstacles could be grouped into five underlying components including: component 1 – weak awareness and inadequate training, component 2 – insufficient support of the authority, component 3 – economic consideration, component 4 – immature market and component 5 – barriers related to site activity.
Practical implications
Based on the findings, industry practitioners' understandings about the barriers to better performing construction and demolition waste management in China can be deepened. Furthermore, the results also provide useful information for developing strategies to improve the performance of construction and demolition waste management in China.
Originality/value
Major obstacles to improving the performance of construction and demolition waste management in China are identified and analyzed in this study.
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Yiming Tang, Xiucun Wang and Pingping Lu
– The purpose of this paper is to examine how Chinese consumer attitude mediates factors that influence their purchase intention toward low-displacement vehicles.
Abstract
Purpose
The purpose of this paper is to examine how Chinese consumer attitude mediates factors that influence their purchase intention toward low-displacement vehicles.
Design/methodology/approach
This study utilizes online survey data in China, multiple regression and recursive regression models.
Findings
Consumers’ environmental concern, perceived effectiveness belief and functional value positively affect their attitude toward such products. Consumer attitude positively affects purchase intention. Consumer attitude fully mediates the influence of environmental concern, and partly mediates the effect of perceived effectiveness belief, and functional value on purchase intention. Consumers’ awareness of government policy is not associated with attitude or purchase intention.
Originality/value
This is a first empirical study to systematically examine Chinese consumer attitude's mediation effect on factors influencing their purchase intent toward low-displacement vehicles in China.
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Collaborative writing is an interactive process. It saves time and energy, and it integrates the knowledge of multiple writers. Wiki is a platform for collaborative writing in the…
Abstract
Purpose
Collaborative writing is an interactive process. It saves time and energy, and it integrates the knowledge of multiple writers. Wiki is a platform for collaborative writing in the Web 2.0 era. This paper's aim is to focus on the many benefits of wikis.
Design/methodology/approach
To understand the effect of using wikis on collaborative writing, the authors conducted a laboratory experiment. They measured writing output under three user modalities (face to face, synchronous distribution, and asynchronous distribution) and with two writing tools (a wiki web site and MS Word).
Findings
Compared to the use of MS Word, face‐to‐face collaborative writing with wikis led to significantly higher levels of participation, and externally evaluated quality of the writing product, and satisfaction with the product and process. However there was no significant effect on document length. Satisfaction is significantly higher with wikis than with MS Word in both distributed collaborative writing conditions, but this was not the case for document length and externally evaluated quality.
Originality/value
The paper shows that the findings have important implications for business. First wikis do not require professional instructors to facilitate their use in meetings. Second the confirmation of wikis' effectiveness motivates the use of wikis toward a more open business environment.
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This research seeks to focus on the benefits of social networking service (SNS) based on the principle of six degrees of separation. Since the inception of web 2.0, the popularity…
Abstract
Purpose
This research seeks to focus on the benefits of social networking service (SNS) based on the principle of six degrees of separation. Since the inception of web 2.0, the popularity of social networks (SNS) has continued to increase. Some SNS are based on six degrees of separation (6SNS), and these have emerged as the most frequently visited WWW sites.
Design/methodology/approach
Using a randomized control group pre‐test‐post‐test experimental design, responses to a questionnaire to test the differences among 6SNS users and non‐users on 12 issues of benefit were analyzed.
Findings
The tests show, first, that, compared with traditional virtual communities, SNS evoke higher ratings for “trust in website,” “trust in other members,” and “quality of friends.” Second, SNS can provide users with entertainment and greater social involvement. People who use these sites express positive attitudes about them. Third, no significant differences were found between SNS and traditional internet media on “meeting new friends,” “maintaining relationships,” “searching for friends,” “searching for information,” and “understanding and learning.” These results can be attributed to language differences.
Originality/value
The value of 6SNS is recognized by the business world. In October 2007, Microsoft invested $240 million to buy 1.6 percent shares of Facebook. Today Facebook alone has more than 300 million users. In addition to the perspective from the business world, how the users themselves view 6SNS and what benefits they can get are crucial to its sustainability.
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Simon Ofori Ametepey, Clinton Ohis Aigbavboa and Wellington Didibhuku Thwala
The essence of finance has become essential in the sustainability discussion in recent times as a result of the capital intensive nature of sustainable projects. This has…
Abstract
The essence of finance has become essential in the sustainability discussion in recent times as a result of the capital intensive nature of sustainable projects. This has motivated financial experts and institutions to develop various financial instruments and mechanisms to further advance the course of protecting the environment, and decreasing the release of excess carbon and GreenHouse Gases. This is to also provide the opportunity for funding Green or sustainable infrastructure development. This chapter advances a discourse on matters relating to sustainable financing of infrastructure projects. The fundamentals of sustainable or green funding of infrastructure projects, and sustainable schemes of financing green infrastructure projects are discussed.