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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.

The purpose of this paper is to synthesize a microemulsion and investigate its tribological properties as lubricant. Magnesium alloy warm rolling experiments were conducted. Surface morphology was observed and wear form was summarized. The composition of surface residues was analyzed, which sheds light on the lubrication mechanism of microemulsion.

A microemulsion was prepared with a proper amount of oil, surfactant, cosurfactant, water and other additives for magnesium alloy strip warm rolling. Tribological properties, such as maximum non-seizure load (P_B), friction coefficient (μ) and wear scar diameter (D) of the microemulsion were measured and compared with those of emulsion and rolling oil on an MR-10A four-ball tribotester. The extreme pressure anti-wear coefficients (O) were calculated and compared. Warm rolling experiments were carried out on a Ф 170/400 × 300 mm four-high rolling mill at 240°C to compare the finish rolling thickness and surface quality of rolled AZ31B magnesium alloy strip under four lubrication states, namely, no lubrication, rolling oil, microemulsion and emulsion. The surface morphology after warm rolling was observed with confocal laser scanning microscope and scanning electron microscope, respectively. The composition of surface residues was analyzed with energy dispersive spectrometry and X-Ray photoelectron spectroscopy.

Surface morphology indicated that pitting wear, adhesive wear and ploughing wear were three main forms of wear in magnesium alloy warm rolling. Microemulsion had excellent lubrication properties with less residual oil remaining. Two types of adsorption layers formed on magnesium alloy strip surface were responsible for lubrication properties. MgSO₄ and magnesium stearate in the reaction layer played a key role in anti-wear and friction-reduction in warm rolling.

The study is original and gives valuable information on lubrication mechanism of microemulsion in warm rolling of magnesium alloy strips.

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.

The purpose of this paper is to conduct a comprehensive experimental study to achieve optimal surface roughness of aluminum rolled with freshly ground rollers of two high rolling mills.

Various rolling oils and processing conditions are applied in the rolling process. Resultant surface roughness is measured with a profilometer; and surface topography of aluminum after rolling is observed under scanning electron microscope. In order to examine the oil film thickness (the most critical factor in rolling process), a planimeter is used to measure the area of oil patch resulting from a precisely controlled oil droplet, which in turn allows calculation of outlet oil film thickness as an approximation to inlet oil film thickness in the deformation region.

The experimental results indicate that two major factors have dominant impacts on aluminum's surface roughness in the rolling lubrication process: reduction of roller; and viscosity of lubrication oil. Based upon analysis of the experimental data, optimal roller reduction is found to be within range (23%, 30%) and optimal oil viscosity should be chosen, such that the ratio between inlet oil film thickness in the deformation region and the combined surface roughness is around 1.

According to the authors' observations, the above parameter choices generally assure excellent surface quality of aluminum after rolling.

To develop electrode materials for supercapacitor with superior electrochemical performance and simple preparation process, the purpose of this study is to prepare flexible CC/NiS/a-NiS electrodes with self-supporting structure by loading hydrothermally synthesized a-NiS particles along with nano-NiS on carbon cloth by electroplating method.

The effects of current densities, temperatures and pH values on the loading amount and uniformity of the active substances during the plating process were investigated on the basis of optimization of surface morphology, crystalline structure and electrochemical evaluation as the cyclic voltammetry curves, constant current charge–discharge curves and AC impedance.

The a-NiS particles on CC/NiS/a-NiS were mostly covered by the plated nano-NiS, which behaved as a bulge and provided a larger specific surface area. The CC/NiS/a-NiS electrode prepared with the optimized parameter exhibited a specific capacitance of 115.13 F/g at a current density of 1 A/g and a Coulomb efficiency of 84% at 5 A/g, which is superior to that of CC/NiS electrode prepared by electroplating at a current density of 10 mA/cm², a temperature of 55°C and a pH of 4, demonstrating its fast charge response of the electrode and potential application in wearable electronics.

This study provides an integrated solution for the development of specifically structured NiS-based electrode for supercapacitor with simple process, low cost and high electrochemical charge/discharge performance, and the simple and easy-to-use method is also applicable to other electrochemically active composites.

The purpose of this paper is to investigate how complementors’ marketing capability and technology capability affect their performance. Drawing on social capital theory, the authors examine platform network centrality as a mediator and platform reputation as a moderator of the relationships between these two capabilities and complementor performance.

This study collects data by questionnaire from 154 Chinese firms adopting e-commerce platforms. Hierarchical multiple regression is used to test the hypotheses of this study.

This study finds that complementors’ marketing capability and technology capability positively affect performance by increasing their platform network centrality. Moreover, platform reputation positively moderates the relationship between platform network centrality and complementor performance, and it strengthens the mediating role of platform network centrality.

This paper emphasizes the critical role of marketing capability and technology capability on complementor performance. It explores the improvement path of complementor performance from the perspective of network position, which is a key element for complementors to effectively leverage their capabilities to build competitive advantage.

The purpose of this paper is to examine how abusive supervision affects employee creativity, incorporating departmental identification as a mediator and face as a moderator based on social identity theory.

The study sample consisted of 207 full-time employees in China.

Results indicate that abusive supervision is negatively related to employee creativity and this relationship is fully mediated by departmental identification. In addition, face held by employees plays a moderating role: the direct effect of abusive supervision on departmental identification and the mediating effect of departmental identification are stronger when face is low rather than high.

This study also has major practical implications for organizations. First, the organizations should fully understand the harmfulness of abusive supervision and try to avoid abusive behaviors. Second, the organizations could enhance employee creativity by promoting departmental identification. Third, employees who hold low face should get more attention and support.

This study makes several theoretical implications. First, findings contribute to enriching one’s understanding of the relationship between abusive supervision and employee creativity in China. Second, the domain of abusive supervision is expanded by empirically testing departmental identification as a crucial psychological mechanism explaining the abusive supervision – employee creativity relationship. Third, this study also advances one’s understanding of social identity process by examining empirically moderating effects of cultural value in the relationship between abusive supervision and employee creativity.

In the creation of coal consumption reduction policy, the Chinese Government selected eight provinces as key provinces and encouraged them to replace coal with other non-coal energy, involving Kaldor-Hicks improvement. The purpose of this paper is to answer how much coal can be conserved if Kaldor-Hicks improvement is considered.

A DEA model reflecting Kaldor-Hicks improvement is suggested to calculate the potential of coal reduction, and an endogenous directional distance function model is proposed to calculate the energy consumption efficiency.

The results show that the non-key provinces wasted more coal than the key provinces, although the latter are of more concern. From the Kaldor-Hicks criterion, ten non-key provinces in a certain year can save more coal from an energy substitution policy and eight key provinces cannot. Through measurement of coal and energy efficiency, it is also found that provinces with an abundance of coal perform the worst in China.

Previous studies measuring Chinese saving potential of coal mainly focused on Pareto-Koopmans criterion, not consistent to policy practices. This study changes to Kaldor-Hicks criterion, allowing to make some factors better off and other factors worse off.

The purpose of this paper is to analyze the reliability and validity of doctoral candidates’ innovative personality model.

Based on doctoral candidates’ innovative personality model, this study took the best correlation and the worst correlation into account to predict and demonstrate their innovative ability tendencies. Matlab R2016a, a program of software programming, was used to calculate the contribution degree of each personality factor of doctoral candidates to their innovative ability tendencies.

The reliability and validity of doctoral candidates’ innovative personality model based on grey target theory have been verified, and the prediction for doctoral candidates’ innovative ability tendencies can be realized on the basis of this model.

Scientific and reasonable doctoral candidates’ innovative personality model can play a good guiding role, and its research results have certain practical significance for selecting innovative doctoral candidates, ensuring the training quality of doctoral candidates and cultivating the innovative ability of doctoral candidates. It can be promoted and applied on the basis of its trial operation in Jiangsu.

With regard to the relative degree of the influence of doctoral candidates’ individual personality factors, previous researchers seldom carried out the quantitative research. In this paper, the author sought a quantitative method to describe the degree of such influence and constructed the doctoral candidates’ innovative personality model based on grey target decision making. This study took the positive and negative off-target distance into account and demonstrated the rationality and validity of doctoral candidates’ innovative personality model.

This paper aims to identify the role of the wall slip on the dynamic characteristics of the multi-groove water-lubricated bearing considering rough contact, including stiffness and damping coefficients of the water film and contact stiffness coefficient of the asperity contact.

The modified perturbed average Reynolds equations with the wall slip are derived, and the calculated perturbed hydrodynamic pressures are integrated to obtain the stiffness and damping coefficients of the water film. The elastic-plastic contact model of Kogut and Etsion is used to determine the contact stiffness coefficient.

Numerical results reveal that the wall slip has the more significant impact on the water film stiffness coefficients compared with the damping and contact stiffness coefficients. When the slip angle lies in a reasonable range, the lubrication performance can be effectively improved, especially in the mixed lubrication condition. In addition, it is worth emphasizing that the abrupt change of the water film stiffness coefficients occurs at the region II (pressure zone) in this study.

The influence mechanism of the wall slip on the dynamic characteristics of the water-lubricated bearing considering rough contact is first revealed.