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The purpose of this study is to evaluate the effect of the four tautomeric forms of 2-amino-5-mercatpo-1,3,4-thiadizole (AMT) absorbed on copper surface by the polar or non-polar groups. Polar group of AMT is mostly electronegative with larger N and S atoms as central atoms. 5-amino-1,3,4-thiadiazole-2(3H)-thion (AMT-c) has the highest adsorption energy and is easy to react with copper. The interaction between AMT-c and copper conforms to chemisorption, which is to be further verified by the experiment on the weight loss measurement.

Adsorption behavior of AMT as corrosion inhibitor on copper surface in oil field was studied by weight loss measurement, and the corrosion inhibition mechanism was analyzed. Reactive sites and distributions of tautomeric forms of AMT as inhibitor on Cu(100) crystal plane were calculated by density functional theory.

All atoms of AMT are in the same plane, and AMT is an aromatic ring structure by large p-chain adsorbed on the metal surface by a plane configuration. AMT-c has the highest adsorption energy and also the most stable isomerized product. The determinate locations of AMT on the Cu(100) surface are the bridge and the hollow sites using molecular dynamics. Corrosion of copper can be effectively inhibited by AMT, which is a kind of excellent corrosion inhibitor, and this property is attributed to the polar groups and non-polar groups of AMT that play a role as absorption and shielding on copper surface, respectively. Inhibition efficiency is increased with the increase in the concentration of the inhibitor. The maximum efficiency of 92 per cent is obtained for 50 ppm AMT concentration at 373 K, which is attributed to the presence of extensively delocalized electrons of the phenyl rings, planarity and the presence of lone pair of electrons on N and S atoms, which favored a greater adsorption of inhibitors on copper surface.

Corrosion of copper can be effectively inhibited by AMT, which is a kind of excellent corrosion inhibitor, and this property is attributed to the polar groups and non-polar groups of AMT that play a role as absorption and shielding on copper surface, respectively. Adsorption of AMT as corrosion inhibitor on copper surface obeys Langmuir isotherm. The interaction between AMT and copper conforms to chemisorption, which is to be further verified by the experiment on the weight loss measurement.

WO₃ particles were prepared by the sol-gel method. Tetraethyl silicate (TEOS) was used to obtain a SiO₂-coated WO₃ nanoparticle. Quantum chemical parameters of oleic acid, triethanolamine, glycerol and methyl pentane as dispersants were theoretically calculated. Tribological properties of SiO₂/WO₃ nanocomposite lubricant were carried out on an MRS-10A four-ball friction and wear tester.

The purpose of this study is to investigate the preparation and tribological properties of SiO₂/WO₃ nanocomposite lubricant.

The obtained SiO₂-coated WO₃ nanoparticle (nano-SiO₂/WO₃) with a particle size of about 70 nm. The calculated adsorption energy of triethanolamine on the surface of the steel ball is 554.6 eV, and triethanolamine is selected as the dispersant. The dispersion effect of SiO₂/WO₃ nanocomposite lubricant is good, which shows that triethanolamine oleate plays a good dispersion role in the preparation of lubricant, which is consistent with the calculation results of the adsorption capacity of dispersant. As a good auxiliary lubricant, SiO₂ can improve the tribological properties and wear resistance of WO₃.

Nanocomposite lubricants have been the focus of research in recent years, which could greatly reduce energy consumption. And the SiO₂/WO₃ exhibited excellent lubrication performance as a lubricant additive. The lubrication mechanism of SiO₂/WO₃ nanocomposite lubricant is the synergistic lubrication mechanism of friction film lubrication and antifriction bearing. This study could provide a certain reference for the practical application of nanocomposite lubricants.

N-containing heterocyclic benzotriazole derivatives as new corrosion inhibitor for mild steel contained in emulsion were synthesized, and their inhibition behaviors for mild steel (MS) contained in emulsion were investigated by experiments and theoretical calculations, and this study aims to prove that two new inhibitors have excellent inhibition efficiency for steel corrosion.

2-(1H-benzo[d][1,2,3]triazol-1-yl)-N,N-dioctylacetamide (BTN) and O-(3-(1H-benzo[d] [1,2,3]triazol-1-yl)propyl) S-(2-(dioctylamino)-2-oxoethyl) carbonodithioate (BTSC) as a new corrosion inhibitor were synthesized, and their inhibition behaviors for MS contained in emulsion were investigated by gravimetric experiment, electrochemical tests and theoretical calculations.

Results of gravimetric experiment, electrochemical tests show that BTSC exhibit excellent inhibition performance, and it has a higher inhibition efficiency of 96.6% than that BTN. The resultant adsorption films from BTN/BTSC adsorbed on MS, effectively inhibiting the corrosion of MS is mainly through chemisorption and follow to Langmuir’s adsorption isotherm.

Experimental and theoretical calculations display that two new synthesized inhibitors are excellent corrosion inhibitor for MS contained in emulsion. Electrons of inhibitors mainly focus on the C, N, S and O atoms, which demonstrate these atoms are the centers of negative charge, and they supply electrons to Fe atoms through coordination bonds.

Corrosion inhibitors for copper immersed in emulsion were investigated by experiments and theoretical calculations, and this study aims to propose a new inhibition mechanism of the inhibitors having protective effects for copper corrosion.

Adsorption behavior of penta-heterocycles (thiophene, 1,2,5-oxadiazole, furan, 2 H-1,2,3-triazole, pyrrole and 1,2,5-thiadiazole) as corrosion inhibitors for copper immersed in oil-in-water (O/W) emulsions was investigated by weight loss, electrochemical tests, morphological characterization and theoretical calculations.

The orders of inhibition effect are furan < pyrrole < thiophene < 1,2,5-oxadiazole < 2H-1,2,3-triazole < 1,2,5-thiadiazole, and 1,2,5-thiadiazole at 0.5 mM has the best inhibition effect for copper immersed in emulsion. The results of scanning probe microscope, scanning electron microscope and electrochemical test show that a protective barrier can be formed on the surface of copper substrate with six corrosion inhibitors, thus effectively inhibiting the corrosion of copper mainly through chemisorption and following Langmuir’s adsorption isotherm.

Quantum chemical and molecular dynamic simulations demonstrate that all these compounds attached to Cu matrix with a flat-adsorption mode to prevent the emulsion corrode copper. Adsorbed inhibitors act as a barrier at Cu matrix to block corrosion and improve hydrophobicity.

This paper aims to investigate the preparation of AlN and Al₂O₃, as well as the effect of nano-AlN and nano-Al₂O₃, on friction and wear properties of copper-steel clad plate immersed in the lubricants.

Nano-AlN or nano-Al₂O₃ (0.1, 0.2, 0.3, 0.4 and 0.5 Wt.%) functional fluids were prepared. Their tribological properties were tested by an MRS-10A four-ball friction tester and a ball-on-plate configuration, and scanning electron microscope observed the worn surface of the plate.

An increase in nano-AlN and Al₂O₃ content enhances the extreme pressure and anti-wear performance of the lubricant. The best performance is achieved at 0.5 Wt.% of nano-AlN and 0.3 Wt.% of nano-Al₂O₃ with PB of 834 N and 883 N, a coefficient of friction (COF) of approximately 0.07 and 0.06, respectively. Furthermore, the inclusion of nano-AlN and nano-Al₂O₃ particles in the lubricant enhances its extreme pressure performance and reduces wear, leading to decreased wear spot depth. The lubricating effect of the nano-Al₂O₃ lubricant on the surface of the copper-steel composite plate is slightly superior to that of the nano-AlN lubricant, with a COF reaching 0.07. Both lubricants effectively fill and lubricate the holes on the surface of the copper-steel composite plate.

AlN and Al₂O₃ as water-based lubricants have excellent lubrication performance and can reduce the COF. It can provide some reference for the practical application of nano-water-based lubricants.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2023-0255/

The purpose of this paper is to improve lubrication and anti-corrosion properties of the water-in-oil (W/O) microemulsion for rolling of copper strip and sheet to replace the traditional rolling oil.

The W/O microemulsion is prepared by using hydrogenated base oil, a deionized aqueous solution of 0.03 mol/L of Na2SO4 and composite emulsifier such as Sp20, Tx-7 or sodium petroleum sulfonate. Tribological behavior of the microemulsions and traditional cold rolling oil was conducted by MR-10A four-ball tester. The lubrication performance of microemulsion for cold rolling of copper strip was performed by cold-rolling experiment. The morphology of worn surface and the rolled copper was characterized. Anti-corrosion properties of microemulsion for rolled copper was investigated, and the corroded surface was analyzed by X-ray photoelectron spectrometer (XPS).

The results show that the extreme pressure and antiwear properties of the microemulsions have been improved; the average friction coefficient of the improved microemulsion is 0.065, which is 30% lower than the commercial cold rolling oil. For cold rolling of copper strip, the microemulsion has a higher thinning effect than the commercial cold rolling oil, and a smooth surface is obtained and the surface roughness (Sa) is decreased by 6.8%. The XPS analysis indicated microemulsion adsorbed on the copper surface mitigate the corrosion of oils.

This paper used the prepared W/O microemulsion as a new lubricant in the process of rolling for copper strip and sheet in industry, demonstrating the microemulsion has broad application prospects in the future.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2020-0227/

With the emergence of a variety of communication channels on social media, employees have more opportunities to engage with external stakeholders for or against their organizational brand. In such a context, focusing on negative word-of-mouth (NWOM) as an employee’s negative discretionary brand-oriented behavior, the current study aimed to identify negative emotions that can serve as drivers for NWOM more strongly than for counterproductive workplace behavior (CWB), relying on the discrete emotion perspective. This study also aimed to examine whether employees’ perceived brand knowledge can directly diminish employees’ NWOM and CWB and attenuate the influence of negative emotions.

A questionnaire was used to gather relevant data, which were analyzed by structural equation modeling.

The findings showed that anger was more strongly associated with employees’ NWOM than withdrawal and that envy was more strongly associated with CWB toward individuals than employees’ NWOM. Employees’ perceived brand knowledge was negatively associated with both NWOM and CWB directly and mitigated the association of negative emotions such as anger and envy with CWB, but not with NWOM.

Based on the discrete emotion perspective, the current study explored the relative magnitude of emotional antecedents for employees’ NWOM and conventional CWB. Also, it expanded the previous findings on the positive effects of perceived brand knowledge on the positive outcomes of employees’ actions and its mitigating effects on NWOM and CWB.

Modern construction projects are increasingly complex and rely heavily on multi-discipline collaboration, and this leads to a more and more decentralized project-based structure widely adopted in the construction industry. While job satisfaction (JS) and job performance (JP) have been heavily studied previously, few considered the impact of organizational structure and none investigated the relationship between the organizational decentralization degree with JS and JP. This research aims to fill this research gap and investigate the impacts of organizational decentralization degree on JS and JP and facilitate a better project management practice for large-scale construction projects.

This research firstly establishes four hypotheses based on the literature review on general project-based organizations, then the hypotheses are tested by a survey covering 25 large complex construction projects in China. A hierarchical linear model analysis was carried out to analyze the survey data and to study the relationships between organizational decentralization degree, job satisfaction and job performance.

Analysis results show that projects' employees' JS and JP are positively correlated with the construction project organizations' decentralization degree, respectively. The decentralization degree has a higher impact on JS than on JP. Employees' JP is positively correlated with their JS, and a higher decentralization degree leads to a more significant positive impact that JS puts on JP.

The findings are new evidence of how construction organization structure and its decentralization degree can affect project employees' JS and JP. This research provides valuable guidance for the industry's management practice and is particularly important for large, complex and highly decentralized construction projects.

To present the mechanism, on which the first module was successfully designed – the automated installation application system, in the grand automated management and evaluation for community health service (CHS) sector of China.

The automated installation application system is constructed on the platform of Visual FoxPro8.0. The construction consists of five steps. The first is to establish the “item.” The function of “the item” is to trace all procedures, forms, menus, and various databases, such as tabulated data, summary data, and other types of data. The second is to establish the customer log‐in module. This module needs to contain a roll book of authorized customers. The third is to construct the subsystem management interface. This interface includes: entering installation the application, modifying and saving and transferring out the information, searching, printing blank form and statement. The fourth is to establish a roll book of all forms and the database of all the forms. The fifth is to establish the main procedure, connecting all the modules in the working order.

The main advantage of the system is that it is helpful for the characteristics of speedy information importation, clear and straight to the point, as well as the secure and accurate data transfer.

Automated management and evaluation for CHS heavily depends on the initial activation and this initiation is started using the system of installation application.

This paper aims to investigate how brand identity is co-created, with a specific focus on how employees contributed to the process in a five-star hotel setting. The focus of this study is on understanding how two hotels planned and executed their brand identity strategy simultaneously, differentiating one from the other and how employees actively participated in this process.

A longitudinal case study approach was adopted, centred on building the identity of two luxury hotels owned by a single company in Seoul, Korea. Various organizational documents were collected and analyzed to understand the brand identity of the hotels and how brand co-creation has been implemented. In addition, semi-structured in-depth interviews were conducted with 42 employees to understand the brand co-creation process from their perspective.

The brand co-creation process of the hotels was conducted simultaneously and evolved over the following four phases, with employees’ roles varying in each phase, namely, establishing a clear brand identity strategy; designing and selecting sensory identity; aligning organizational identity; and delivering brand identity through external communication. Employees that participated in brand co-creation enhanced their brand knowledge, developed emotional bonds with the brand and were motivated to deliver the brand identity. Furthermore, those that immersed themselves in the new brand identities were able to enable positive guest perceptions towards the brand image, which consequently enhanced employees’ pride in their work.

This research advances the brand management literature in defining branding and brand identity elements, as well as emphasizing the importance of consistent branding. In addition, the current study expands the scope of internal branding, highlighting the process of brand co-creation and the role of employees as active participants. Moreover, it reveals that employees’ participation enhances not only their brand knowledge but also their emotional bonds with the brand. The proposed conceptual framework demonstrates the flow of branding elements, brand identity elements and the “infinite loop” of employee participation in brand co-creation.

The case study approach adopted here enables an in-depth investigation of employee participation in brand co-creation, including their different roles and activities in the process; a phenomenon that has not been adequately explored in previous research.