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The purpose of this paper is to examine the transformations of prosthetic practices in China, as well as the daily experiences and dilemmas arising from the everchanging practices since 1949. On the basis of materials, this paper explores an everyday perspective to review the history of technology.

Ethnography was collected with the application of participant observations, informal interviews and in-depth interviews during a 13-months study at a rehabilitation center in Chengdu, China. The literature on prosthetic manufacturing was also reviewed for this paper.

China's prosthetic technology seems to evolve from traditional to modern. However, this progressive narrative – innovation-based timeline (Edgerton, 2006, xi) – has been challenged by daily practices. Due to institutional pressures, prosthetists are in a dilemma of selectively using their knowledge to create one kind of device for all prosthesis users with a certain kind of disability, thereby regulating the physical and social experiences of prosthesis users. Besides, prosthesis users are accustomed to prostheses made with old techniques, and must correct themselves from old experiences to the daily practices recognized by the selected techniques.

This paper provides a cross-cultural case to reexamine Edgerton's criticism of the progressive and orderly innovation-centric technological narrative. More importantly, it reviews the history and practices of China's prosthetics from daily experiences rather than Edgerton's concentration on technology; therefore, it provides an everyday perspective for future research on technological transformations.

This paper describes a study on the corrosion behaviour of archaeological bronze in simulated groundwater by means of a simulated occluded cell. The study revealed migration, enrichment and deposition patterns of ions in the environment and the cations produced by anodic dissolution during localised corrosion of bronze. The cycle voltametry technique was utilised for the first time on the study of electrochemical behaviour of the bronze/simulated occluded solution interface. The potential and current peaks of oxidation‐reduction at the cathode and anode in the occluded solutions at various time intervals facilitated a study of the corrosion products formation processes and their formation speeds.

By investigating trust in the organization as a mediator and traditionality as a moderator, this study aims to examine the effect perceived organizational exploitation poses on frontline hotel employees’ service performance.

A three-wave survey that targets 219 supervisor–subordinate dyads from four Chinese hotels was conducted to test the hypotheses. The authors used SPSS 20.0 and AMOS 21.0 to analyze the data and verify the theoretical model.

This study found that perceived organizational exploitation exerts a destructive impact on frontline hotel employees’ service performance. Trust in the organization is a full mediator of the link connecting perceived organizational exploitation to service performance. Furthermore, traditionality weakens perceived organizational exploitation’s impact on trust in the organization and subsequent service performance.

The authors’ findings remind hotels to cease exploiting their employees to avoid compromising service performance. Hotels should also endeavor to instill trust among employees toward the hotel and allocate more attention to employees with lower levels of traditionality.

First, to the best of the authors’ knowledge, this study is among the first to explore the impact of perceived organizational exploitation on frontline hotel employees’ service performance. Second, this study reveals a novel mechanism underlying the connection between perceived organizational exploitation and service performance. Finally, this study identifies frontline hotel employees’ traditionality as a vital moderator that mitigates the negative relationships among perceived organizational exploitation, trust in the organization and service performance.

The purpose of this paper is to investigate the microstructures, slag inclusions, morphology and composition of ancient Chinese iron coins exhumed from Emei Mountain and Baoji after 818‐966 years of being imbedded underground.

Metallography, scanning electron microscopy, energy dispersive spectrometry, X‐ray photoelectron spectrometry and Fourier transform infrared spectroscopy were employed.

The results showed that archaeological coins exhibited characteristics of a typical hypoeutectic white cast iron, with slag inclusions of FeS strips and phosphate. Porous or hexagonal platey corrosion products were discovered on the archaeological iron coin, which were mainly identified as Fe₂O₃, FeOOH, Fe_x(OH)_1−xCO₃ and Fe_x(OH)_1−xSO₄. The possible corrosion mechanisms for the iron coins were discussed based on the corrosion products.

This study revealed the characterization of corrosion products on archaeological iron coins and may provide guidance for the preservation of archaeological iron.

The chemical behaviour within the occluded cell of simulated cast iron artefact in 3.5 percent NaCl solution has been investigated by means of a simulated occluded cell. It was observed that the pH value and the amount of Cl⁻ migration in the occluded cell were related to the quantity of passing electric current. Electrochemical techniques were capable of providing information on the behaviour of the cast iron in a simulated occluded cell at various time intervals. The results of potentiodynamic polarisation and impedance measurements indicated that corrosion potentials became more negative and the cast iron was corroded more seriously. SEM micrographs clearly revealed the morphologies of specimens after simulated occluded cell galvanostatic tests for different time intervals at 1 mA/cm² anodic current density. An auto‐catalysing process was responsible for the enrichment of chloride ions in occluded cell which was confirmed by Energy Dispersive Spectroscopy (EDS).

The main purpose of this study was to investigate the effect of chloride on the atmospheric corrosion of cast iron in an atmosphere with sulphur‐bearing pollutants.

Periodic wet‐dry tests, surface tension tests, electrochemical impedance (EIS) measurements, stereoscopic microscopy, scanning electron microscopy and energy dispersive atomic X‐ray analysis were used to investigate the corrosion processes and products. Weight loss measurements, electrochemical theory, as well as ion adsorption theory and penetration theory were used to explain the corrosion process.

The experimental results demonstrated that weight loss measurement approximately obeyed the relationship: ΔW=At^B. With addition of NaCl, the value of A decreased, whereas B increased. It is worth noting that NaCl acted as an inhibitor in the HSO₃⁻ bearing pollutant during the initial corrosion stage. However, as corrosion continued, the penetration effect of chloride and the different characteristics of the corrosion products tended to dominate the corrosion process, which led to changes of the corrosion rate. Both the EIS measurements and surface tension tests agreed well with the results of weight loss measurements.

The initial corrosion stage showed good agreement with associated surface activity. The paper explains the effect of chloride on the atmospheric corrosion of cast iron in sulphur bearing pollutants from a new viewpoint.

The main purpose of this study was to investigate the corrosion behaviour of simulated archaeological iron in Cl⁻, NO₃⁻ and HSO₃⁻ bearing pollutants.

Periodic wet‐dry test, potentiodynamic polarization experiments and surface tension tests were used to study the rule of corrosion rate. Scanning Electron microscopy with EDAX, stereoscopic microscopy and X‐ray diffraction were also used to identify the corrosion products and mechanism. Weight loss measurement, electrochemical theory, as well as ions adsorption theory and penetration theory were used to explain the different corrosion behaviour.

The experimental results demonstrated that the attack of anodic ions to the metal at the initial corrosion stage showed great agreement with their surface activity. However, as corrosion progressed, the different reaction mechanisms and the penetration effect of anions as well as the characteristics of the corrosion products (intermediate products and final products) begin to control the corrosion process.

The initial corrosion rate was found to show agreement with the surface activity of anions. From a new viewpoint, this paper explains the different corrosion behaviour of Cl⁻, NO₃⁻ and HSO₃⁻ anions to simulated archaeological iron and offers reference to the individual who pursues in corrosion and protection of metal.

Specimens of 304 stainless steel with various martensite contents were prepared by a low temperature (−70°C) elongation method. Optical microscopy and transmission electron micrography were used to study the phase structure of the samples. A simulated occluded cell (OC) and electrochemical impedance spectroscopy were used to study the chemical and the electrochemical changes within pits on 304 stainless steel containing the different martensite contents. The EIS results showed that the martensite phase decreased not only the solution resistance in pit, but also the polarization resistance value between metal and solution in pit. The composition of the passive film in OC solution was studied by X‐ray photoelectron spectroscopy. It was observed that martensite transformation was a very important factor in changing the composition of the passive film. The martensite phase destroyed the integrality and compactness of the passive film. For these reasons, pit propagation in Type 304 stainless steel was accelerated with increasing martensite content.

It is essential to level the drilling platform across which a drilling robot travels in a slant underground coal mine tunnel to ensure smooth operation of the drill rod. However, existing leveling methods do not provide dynamic performance under the drilling conditions of the underground coal mine. A four-point dynamic leveling algorithm is presented in this paper based on the platform attitude and support rod displacement (DLAAD). An experimental drilling robot demonstrates its dynamic leveling capability and ability to ensure smooth drill rod operations.

The attitude coordinate of the drilling robot is established according to its structure. A six-axis combined sensor is adopted to detect the platform attitude, thus revealing the three-axis Euler angles. The support rod displacement values are continuously detected by laser displacement sensors to obtain the displacement increment of each support rod as needed. The drilling robot is leveled according to the current support rod displacement and three-dimensional (3 D) attitude detected by the six-axis combined sensor dynamically.

Experimental results indicate that the DLAAD algorithm is correct and effectively levels the drilling platform dynamically. It can thus provide essential support in resolving drill rod sticking problems during actual underground coal mine drilling operations.

The DLAAD algorithm supports smooth drill rod operations in underground coal mines, which greatly enhances safety, reduces power consumption, and minimizes cost. The approach proposed here thus represents considerable benefits in terms of coal mine production and shows notable potential for application in similar fields.

The novel DLAAD algorithm and leveling control method are the key contributions of this work, they provide dynamical 3 D leveling and help to resolve drill rod sticking problems.