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This research aims to study the influence of limestone filler on rebar corrosion.

Mortar samples containing 35% calcareous filler and with a rebar inserted in the axis, were cast. Specimens were cured at the open air and during 28 days in lime water. After curing, they were submerged in two electrolytes (tap water and 3% NaCl) and corrosion parameters (corrosion potential and corrosion current) were monitored over time by d.c. techniques. Simultaneously, electrochemical noise measurements were carried out. After corrosion tests, rebars were pulled out by lateral compression, and their surface observed by scanning electron microscopy.

In general, carbonate additions impaired mortar protective properties, especially in the presence of chloride and changed the nature of the protective layer on rebars. The curing process did not introduce significant differences except for mortars with a high water cement ratio cured in lime water for which the beneficial effects of the simultaneous presence of carbonate and lime in the pore solution could be appreciated. The role of carbonate additions is to provide carbonate anions to passivate rebars. This passivation process caused corrosion rates not to be so high. Carbonate anions also deposited on oxide spots which were rendered passive but this process was not uniform. Certain areas on the rebar underwent intense carbonation while others showed increased corrosion rates.

There are not many corrosion studies about the influence of limestone filler on rebars corrosion. Particularly, this paper deals with mortars containing high percentages of carbonate additions. Results showed that the presence of this type of admixture changes the structure of the passive layer and, sometimes, may increase corrosion rates.

The screening of lube oil performance prior to field trials is the most significant for the formulation of novel lubricants. This paper aims to investigate the efficacy of trimethylolpropane trioleate oil (TMPTO) based lubricants with different additives.

In this endeavor, initially five lubricating blends along-with TMPTO based oil with variable additives were evaluated for their tribological performances using ASTM standards. Out of these, the top three best-performing oils were further investigated for possible physical or chemical synergies among lube oils, additives and ball surface using SEM. The molecule structures of TMPTO based lube oils were confirmed using Fourier transform infrared spectroscopy (FTIR).

The wear preventive and extreme pressure characteristics of different TMPTO based samples were evaluated and compared for compatibility and synergy of additives. Morphological analysis of SEM images was used to understand the wear behavior of the worn surfaces.

Further investigation of TMPTO oil on its oxidation stability at high temperature and pressure to make it technologically competitive and commercially viable metal-working lubricant is suggested.

This paper highlights the tribo-effects of TMPTO to be rendered as a suitable lubricant for metal-cutting operations. The surface morphology of the worn-out surface significantly demonstrates the effect of loading conditions.

An overview has been presented on the topic of alternative surface finishes for package I/Os and circuit board features. Aspects of processability and solder joint reliability were described for the following coatings: baseline hot‐dipped, plated, and plated‐and‐fused 100Sn and Sn‐Pb coatings; Ni/Au; Pd, Ni/Pd, and Ni/Pd/Au finishes; and the recently marketed immersion Ag coatings. The Ni/Au coatings appear to provide the all‐around best options in terms of solderability protection and wire bondability. Nickel/Pd finishes offer a slightly reduced level of performance in these areas which is most likely due to variable Pd surface conditions. It is necessary to minimize dissolved Au or Pd contents in the solder material to prevent solder joint embrittlement. Ancillary aspects that include thickness measurement techniques; the importance of finish compatibility with conformal coatings and conductive adhesives; and the need for alternative finishes for the processing of non‐Pb bearing solders are discussed.

The purpose of this study is to predict the thermal protective performance (TPP) of flame-retardant fabric more economically using machine learning and analyze the factors affecting the TPP using model visualization.

A total of 13 machine learning models were trained by collecting 414 datasets of typical flame-retardant fabric from current literature. The optimal performance model was used for feature importance ranking and correlation variable analysis through model visualization.

Five models with better performance were screened, all of which showed R2 greater than 0.96 and root mean squared error less than 3.0. Heat map results revealed that the TPP of fabrics differed significantly under different types of thermal exposure. The effect of fabric weight was more apparent in the flame or low thermal radiation environment. The increase in fabric weight, fabric thickness, air gap width and relative humidity of the air gap improved the TPP of the fabric.

The findings suggested that the visual analysis method of machine learning can intuitively understand the change trend and range of second-degree burn time under the influence of multiple variables. The established models can be used to predict the TPP of fabrics, providing a reference for researchers to carry out relevant research.

The findings of this study contribute directional insights for optimizing the structure of thermal protective clothing, and introduce innovative perspectives and methodologies for advancing heat transfer modeling in thermal protective clothing.

Due to the special service environment of superalloys, this paper aims to obtain effects of temperature and Ti addition on high temperature oxidation behavior of Co-Al-W-B alloys.

Isothermal oxidation experiment of Co-Al-W-based alloys were carried out at 800°C, 900°C and 1000°C for different times (3, 5, 10, 20, 50 and 100 h) referring to the method of HB5258-2000. Oxidation weight gain curves and oxidation products were detected.

The results showed that the average oxidation rates of Co-Al-W-B alloy at 800 °C and 900 °C were 0.489 g·m⁻²·h⁻¹ and 0.888 g·m⁻²·h⁻¹, respectively, which belonged to an antioxidant grade. However, the average oxidation rate at 1000 °C was 2.068 g m⁻²·h⁻¹, belonging to the secondary oxidation resistance class. In the alloy with Ti addition, dense Ti oxides film were formed at the early oxidation stage and then gradually diffused later, which can increase the oxidation resistance of the alloys to some extent. By analyzing the oxidation products of Co-Al-W-B alloy, it was found that a dense Al₂O₃ layer could be formed when the alloy was oxidized at 800°C. The continuous Al₂O₃ layer would prevent the oxygen from further spreading and make the alloy into the stable oxidation stage. However, only a non-dense Al₂O₃ layer were observed with 900°C oxidation.

It can provide references for the composition design, preparation process optimization and protective coating selection of the γ′ phase strengthened cobalt-base superalloys.

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Examines the thirteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

This study aims to characterize the composition of the tribo-layer formed during sliding of steel in the presence of crude jatropha oil (CJO) and epoxidized jatropha oil (EJO) under boundary lubricant application.

CJO was obtained from a local market and used as received. EJO was obtained by epoxidation process with peroxyformic acid catalyzed by acidic ion exchange resin. The tribological test was conducted by the four ball method according to ASTM 4192. Wear scars generated on the lower balls were used to characterize the tribo-layer. Energy-dispersive X-ray and X-ray photo spectroscopy analysis were conducted to characterize the tribo-layer composition.

EJO shows a lower friction coefficient compared to CJO. Moreover, EJO also shows better wear preventive properties compared to CJO. The oxidation of CJO and EJO has lead chemisorption of the oil to steel surface to cause formation of protective layers for the steel surface. The layers were constructed from inorganic oxide in the form of iron oxides and silicon oxide together with organic layers in form of aldehyde, ketone and carboxylic acid. The formation and removal of this layer from rubbing sites are considered to affect wear-preventive and friction behaviour of steel lubricated with CJO and EJO.

This works highlights friction and anti-wear characteristics of CJO and EJO. This work also presents the composition of the tribo-layer that formed because of the sliding of steel lubricated with CJO and EJO. The method and result can be used for further investigation and development of lubricant.

The purpose of this paper is to present a study of corrosion properties of the highly corrosion‐resistant stainless steel Prokron 11Nb, which is suitable for use in high‐temperature and high‐pressure systems.

Prokron 11Nb was immersed in 0.1 M H₂SO₄ that had been previously sparged with CO₂ and was exposed to high pressures within the range of 1‐300 bar at a constant temperature of 25°C. Treated surfaces were scanned with an electronic microscope (scanning electron microscope) equipped with energy spectrum distribution (energy dispersive spectroscopy) to analyze the morphologies and compositions of surface deposits. Corrosion properties were measured using the potentiodynamic method and electrochemical impedance spectroscopy.

The corrosion rate decreased with increasing CO₂ pressure, which accelerated surface passivity, but only up to a pressure of 200 bar. Higher pressures (300 bar) increased the corrosion rate. The trends in corrosion rate with CO₂ pressure agree with the stability of a protective layer where iron carbonate is present.

A high‐pressure CO₂ treatment at low temperature is found to be a useful method for improving the passivity of stainless steel. Iron carbonate, which is the result of CO₂ corrosion, forms a stable protective layer on the steel surface and this lowers the corrosion rate.

Examines the sixteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.