Lina Qiu, Yanan Mao, Aijun Gong, Weiwei Zhang, Yanqiu Cao and Lu Tong
Bdellovibrio bacteriovorus is a gram-negative predatory bacterium which can potentially inhibit microbiologically influenced corrosion by preying on sulfate-reducing bacteria…
Abstract
Purpose
Bdellovibrio bacteriovorus is a gram-negative predatory bacterium which can potentially inhibit microbiologically influenced corrosion by preying on sulfate-reducing bacteria (SRB). However, no researches about the inhibition are reported according to the authors’ knowledge. The purpose of this paper was to investigate the Inhibition effect of B. bacteriovorus on the corrosion of X70 pipeline steel induced by SRB.
Design/methodology/approach
The effect of B. bacteriovorus on the growth of SRB was studied by measuring the optical density at 600 nm (OD600) and sulfate concentration in culture medium. X70 pipeline steel was used as the test material to investigate the anti-corrosion effect of B. bacteriovorus on SRB by conducting electrochemical analysis (including Tafel polarization curves and electrochemical impendence spectroscopy) and weight loss measurement.
Findings
B. bacteriovorus could inhibit the growth of SRB in culture medium by its predation on SRB, which led to decrease of OD600 value and increase of sulfate concentration. The results of electrochemical analysis indicated that B. bacteriovorus had positive inhibition efficiencies on SRB-induced corrosion of X70 pipeline steel. Moreover, corrosion rate of X70 pipeline steel was declined from 19.17 to 3.75 mg·dm-2·day-1 by the presence of B. bacteriovorus.
Originality/value
This is the first report about using B. bacteriovorus to inhibit the corrosion induced by SRB. Compared to other anti-corrosion methods, the microbial inhibition methods exhibit more considerable application value due to its low cost, high efficiency and non-pollution.
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The purpose of this paper is to examine the nature of the China–North Korea alliance that has been often described as “Lips and Teeth” or “Blood Tied.”
Abstract
Purpose
The purpose of this paper is to examine the nature of the China–North Korea alliance that has been often described as “Lips and Teeth” or “Blood Tied.”
Design/methodology/approach
In order to make accurate assessment of the China–North Korea relations, this paper conducts indepth historical analysis of the relations. The relations between two countries were formed in 1940s and lasts until today.
Findings
However, by looking into the history of two countries, this paper argues that the bilateral relations are not an extraordinary but an ordinary state-to-state relations dictated by national interests. Changes in their calculus of national interests affect their relations. They cooperate with each other when they see mutual benefit in doing so and tension arises when there is a conflict of interests. What should be noted is that the changes in the nature of relations is different from the deterioration in the relations. Recent improvement of their relations supports this paper’s argument.
Originality/value
This paper suggests new look at the China–North Korea relations that has been considered as an extraordinary relations. The findings of this paper suggest that the alliance relation is not different from other state-to-state relations where conflict and cooperation occurs based on their national interests.
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Jitai Han, Yanan Ge, Yuxin Mao and Meiping Wu
The purpose of this paper is to mainly focus on the relationship between the scanning strategy and surface quality. Surface quality, including surface roughness and flatness, is…
Abstract
Purpose
The purpose of this paper is to mainly focus on the relationship between the scanning strategy and surface quality. Surface quality, including surface roughness and flatness, is important for printed parts. So this paper optimizes the surface quality by changing the scanning strategy.
Design/methodology/approach
This paper is based on the phenomenon after the printed parts. A clear trend can be seen that the surface roughness on the side face shows a clear zigzag shape, so an optimized scanning strategy is used. Surface roughness in measured in macrostructure first by Mitutoyo and the flatness is measured by Hexagon Metrocogy. After that, microstructure on the side face is seen by RTEC to explain this phenomenon.
Findings
The surface quality on the side face shows a significant optimize by changing the scanning strategy. The surface quality on the positive face has some optimization to some degree.
Originality/value
This paper determines the relationship between the surface roughness on the side face and the scanning strategy. Few studies focus on the surface roughness, especially on the side face. Some studies try to optimize the surface roughness on the positive face. However, researchers always neglect the surface roughness on the side face. 2. This paper measures not only the surface roughness, but also the flatness. Surface roughness has a significant impact on the surface quality. However, it still has some limitations. Flatness is also measured to make this paper more representative. 3. This paper explains why scanning strategy can affect the surface quality. These images explain the research better and not just at the theoretical level.
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Wenkun Zhang, Jinhua Chu, Tao Zhang and Yanan Wang
In contrast to existing studies, this paper aims to propose that digital transformation does not depend on a single condition; rather, it depends on the interaction between…
Abstract
Purpose
In contrast to existing studies, this paper aims to propose that digital transformation does not depend on a single condition; rather, it depends on the interaction between internal and external factors of a firm. Therefore, the aim of this paper is to examine the effect of a combination of internal and external factors on a firm's digital transformation intention.
Design/methodology/approach
An empirical analysis on a sample of 112 Chinese small- and medium-sized firms was conducted by applying smart-PLS and fuzzy set qualitative comparative analysis (fsQCA).
Findings
The results of smart PLS show that external pressures (institutional and market pressures) and human capital have a positive impact on corporate digital transformation intentions. From a combination perspective, the results of the fsQCA show that there are five causal conditions that lead to high digital transformation intention. In contrast to the net effect, the results of fsQCA show that different combinations of states of internal (human capital, organizational culture and technological capital) and external elements (institutional and market pressures) of the firm are likely to stimulate digital transformation intention.
Originality/value
This study provides empirically based insights into firms' digital transformation intentions and advances the current understanding of the drivers and inhibitors of digital transformation. Unlike most current research, which tends to focus on the net effect of factors influencing the digital transformation of enterprises, this study focuses on identifying the core elements influencing enterprises' digital transformation intention, especially the joint effect of different factors, both internal and external to the enterprise. The combined SEM and fsQCA findings of this paper not only enrich the existing theories on digital transformation but also have high value in guiding the digital transformation of firms.
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Most offender narrative being studied has been in oral forms, produced in the reciprocal process of researcher-(ex) offender interviews. This chapter offers an introduction to a…
Abstract
Most offender narrative being studied has been in oral forms, produced in the reciprocal process of researcher-(ex) offender interviews. This chapter offers an introduction to a variation of offender narrative study within the prison and rehabilitation context: the narrative of written autobiography. Since the early 1940s, Chinese reform institutions have required written autobiographies from new admitters, provided with clear presubscripted guidelines of instructions as well as postcensorship. For this chapter, we trace back and analyse this model based on 28 prisoners' autobiographies in mainland China between 2007 and 2009, as well as archive documents in different historical periods. We have found that the mandatory offender autobiographies are highly functional writings with clear requirements that embody the existing power structure. We have also found considerable commonality with findings in Western contexts on the presence and problems of narrative compliance in rehabilitation. We argue that narrative criminology should further engage in understanding the practice of narrative censorship and co-authorship in criminal justice processes, as it takes on different forms in different historical–social contexts.
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Despite significant advances in previous work, there are still gaps in the research on customers' acceptance of virtual fitting rooms (VFRs). This research aims to highlight the…
Abstract
Purpose
Despite significant advances in previous work, there are still gaps in the research on customers' acceptance of virtual fitting rooms (VFRs). This research aims to highlight the effects of the characteristics of VFRs on the intention to use.
Design/methodology/approach
Fashionable clothing shoppers in Harmony Shopping Plaza and Ginza Shopping Plaza in Jinan, China, were chosen as the main sample. A total of 304 valid questionnaires were collected using a questionnaire QR code, which was scanned to access the questionnaire. Structural equation modeling was used to test the relevant hypotheses.
Findings
The results showed that customers' usage intention (UI) was positively associated with perceived efficiency, design and perceived security. Furthermore, the mediating effects of perceived ease of use and perceived usefulness were significant between design, vividness and UI.
Originality/value
In contrast to existing research, which focuses primarily on the posterior effects of psychological perception and behavior, this paper focuses on the antecedents of customer psychological perceptions. This study also examines the moderating effect of fashion consciousness, which also provides reference value for future research. The findings of this paper provide practical guidance for the promotion of VFRs.
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Changhai Lin, Zhengyu Song, Sifeng Liu, Yingjie Yang and Jeffrey Forrest
The purpose of this paper is to analyze the mechanism and filter efficacy of accumulation generation operator (AGO)/inverse accumulation generation operator (IAGO) in the…
Abstract
Purpose
The purpose of this paper is to analyze the mechanism and filter efficacy of accumulation generation operator (AGO)/inverse accumulation generation operator (IAGO) in the frequency domain.
Design/methodology/approach
The AGO/IAGO in time domain will be transferred to the frequency domain by the Fourier transform. Based on the consistency of the mathematical expressions of the AGO/IAGO in the gray system and the digital filter in digital signal processing, the equivalent filter model of the AGO/IAGO is established. The unique methods in digital signal processing systems “spectrum analysis” of AGO/IAGO are carried out in the frequency domain.
Findings
Through the theoretical study and practical example, benefit of spectrum analysis is explained, and the mechanism and filter efficacy of AGO/IAGO are quantitatively analyzed. The study indicated that the AGO is particularly suitable to act on the system's behavior time series in which the long period parts is the main factor. The acted sequence has good effect of noise immunity.
Practical implications
The AGO/IAGO has a wonderful effect on the processing of some statistical data, e.g. most of the statistical data related to economic growth, crop production, climate and atmospheric changes are mainly affected by long period factors (i.e. low-frequency data), and most of the disturbances are short-period factors (high-frequency data). After processing by the 1-AGO, its high frequency content is suppressed, and its low frequency content is amplified. In terms of information theory, this two-way effect improves the signal-to-noise ratio greatly and reduces the proportion of noise/interference in the new sequence. Based on 1-AGO acting, the information mining and extrapolation prediction will have a good effect.
Originality/value
The authors find that 1-AGO has a wonderful effect on the processing of data sequence. When the 1-AGO acts on a data sequence X, its low-pass filtering effect will benefit the information fluctuations removing and high-frequency noise/interference reduction, so the data shows a clear exponential change trends. However, it is not suitable for excessive use because its equivalent filter has poles at the non-periodic content. But, because of pol effect at zero frequency, the 1-AGO will greatly amplify the low-frequency information parts and suppress the high-frequency parts in the information at the same time.
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Lin Liu, Hongyu Su, Xue Li, Yanan Wang, Qiang Zhang and Jianhua Qian
This paper aims to evaluate the inhibitive effect and adsorption behavior of the 2-amino-5-thiol-1,3,4-thiadiazole vanillin (A) on copper in 3 per cent NaCl solution.
Abstract
Purpose
This paper aims to evaluate the inhibitive effect and adsorption behavior of the 2-amino-5-thiol-1,3,4-thiadiazole vanillin (A) on copper in 3 per cent NaCl solution.
Design/methodology/approach
A thiazole Schiff bases were synthesized, named, 2-amino-5-thiol-1,3,4-thiadiazole vanillin (A), which was fabricated respectively on copper surface by the molecular self-assembled. Evaluation was carried out by electrochemical measurement and surface analysis techniques. Measurement of static friction coefficient scanning electron microscopy and Contact angle analysis were applied, and it is finally confirmed the existence of the adsorbed film. The inhibitive mechanism of A was evaluated by means of quantitative calculation and molecular dynamics simulation.
Findings
The electrochemical measurement indicated that the self-assembled molecular film can effectively inhibit the corrosion of copper sheet, when the concentration was 15 mmol⋅L−1 and the assembly time was 6 h, the corrosion inhibition effect was the best, reaching as high as 97.5 per cent. Scanning electron microscopy results showed that the Schiff base compound forms a protective film on the surface of the copper, which effectively blocks the transfer of corrosion particles to the metal substrate, thereby inhibiting the occurrence of corrosion. Adsorption behavior of A followed the Langmuir’s adsorption isotherm and attributed to mixed-type adsorption. The results of Quantitative calculation and molecular dynamics simulation showed that A was adsorbed on Cu (111) surface in parallel.
Research limitations/implications
In this study, the corrosion inhibition properties of Schiff base film were investigated by combining theory with experiment. Theoretical calculation is helpful to guide the synthesis of efficient and environmentally friendly corrosion inhibitors.
Practical implications
The damage caused by metal corrosion is great. The self-assembled Schiff base membrane synthesized in this paper is simple and compact, and the corrosion inhibition efficiency of copper in 3 per cent NaCl solution is 97.5 per cent.
Social implications
Inhibition of metal corrosion can better save energy and reduce economic losses.
Originality/value
The synthesized Schiff base was prepared on the copper surface by the molecular self-assembled. The Schiff base membrane has a good corrosion inhibition effect on copper in 3 per cent NaCl solution, and the corrosion inhibition efficiency is up to 97.5 per cent.