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In the present study, the effect of ultrasonic shot peening (USSP) on electrodeposited Ni/Ni-TiO 2 coatings on mild steel substrate was analyzed in terms of surface-mechanical and electrochemical properties. USSP was performed on the Ni/Ni-TiO 2 coatings surface deposited mainly from Watt baths with varying peening vibrational amplitude and peening time, and the resulting hybrid coating was analyzed using XRD, SEM, microhardness, scratch test, and corrosion analysis. The XRD analysis revealed a prominent texturing effect and residual compressive stress, which resulted in changes in surface-mechanical and corrosion properties. SEM morphology revealed pore closure following USSP, as well as a positive effect at the coating interface. Surface roughness and dimple size also had an impact on the properties. Microhardness and scratch results showed improvement after peening. The noticeable effect of peening was observed during a corrosion study using potentiodynamic polarization and EIS analysis.

Long‐term ice phenology records quantify the effects of climate change on Northern Hemisphere lakes. This study uses lake ice phenological records across a gradient of lake sizes (0.1–31,967.8 km2 in lake surface area) obtained from community science networks. We compiled in situ ice phenological records for 2,499 lakes across 15 countries for an average of 30 years. These data revealed that for the last 50 years (1971–2020), the annual mean duration of lake ice cover decreased at a rate of 9 days per decade, with a regime shift in lake ice phenology in the late 1980s. We projected that at the end of the century (2070–2099), ice duration will decrease by an average of 10 days when compared to the historical time period (1971–2000) for the shared socioeconomic pathway (SSP) 1–2.6 climate scenario (SSP126), 23 days for SSP370, and 28 days for the SSP585. Impending human development can enhance or attenuate lake ice loss, as adaptation strategies can accelerate fossil fuel use, result in conflict, or seek strategies apart from fossil fuel development. These future pathways have critical implications for the future preservation of lake ice cover. Key Points A regime shift was observed in North American lake ice phenology in the late 1980s Northern Hemisphere lakes may lose 10–28 days of ice cover by the end of the 21st century Lake ice phenology will become more unpredictable, especially under higher warming scenarios

The current research aims to develop a hybrid surface engineering process combining electrodeposition and ultrasonic shot peening (USP) to enhance surface-mechanical properties and coating strength. A thin nickel coating was deposited on the copper substrate through an electrodeposition process and the coating contained few microcracks and pits. The obtained coating was ultrasonically shot peened with different peening times and the number of peening shots (balls). The microstructural evolution, phase analysis, surface hardness, and scratch resistance of nickel coatings and peened coatings were characterized and discussed. The impact of peening based on duration and quantity of shots (ball), which induced grain refinement and compressive residual stress on the surface of the coating has been investigated. The multi-impact shots at a high velocity strike the coated surface and reduce the thickness of the electrodeposited nickel, creating better adhesion. The peening treatment resulted in enhancing the microhardness of the coated nickel from 123 Hv to 328 Hv. The tensile residual stress of coated nickel has been converted into compressive nature. The plastic deformation developed on the coated surface by USP and other factors lowered the coefficient of friction and enhanced the scratch resistance of the coating. Based on the result, it was established that USP has a broad and effective strengthening approach for the nickel coating deposited on soft substrate to increase its compactness and strength.

Rock failure is a serious problem in rock engineering environments. Rock failure modes, however, are complex and difficult to quantify or predict. A comprehensive study on rock failure modes at laboratory scale is, therefore, potentially important as it helps recognize the adequacy of the support designed on the basis of the nature of an engineering work. With due need, this paper analyzes the failure modes of granite, schist, and sandstone under uniaxial compression, Brazilian, and point load tests in relation to corresponding strengths. The nature of the principal failure mode changes from axial splitting to shearing along a single plane to multiple fracturing in the case of both granite and sandstone specimens as uniaxial compressive strength (UCS) increases. In the case of schist, specimens failed at low UCS show failure along foliations whereas specimens which do not fail along foliations portray high strength. The relation between failure modes of all three rocks under uniaxial compression and corresponding UCS values was broadly explained in terms of damage evolution of the rocks. Granite and sandstone specimens failed mainly following central or central multiple type of fracturing whereas schist specimens principally failed by layer activation in combination with either central or non-central fractures over the entire range of determined Brazilian tensile strength. In the case of granite and sandstone, central multiple failure mode corresponds to high tensile strength. Descriptions of different failure modes under point loading were presented. It was found that granite and sandstone specimens generally fail through the rock materials in one or more extensional planes containing the line of loading. Failure patterns showing triple junctions correspond to high point load strength indices. In the case of schist, specimens failed along foliations show a low point load strength index whereas specimens failed through material with a single extensional plane result in high strength.

The current communication deals with elaboration of electrodeposited graphene oxide (GO)-reinforced copper composite coating with tribomechanical and electrical properties. Graphene oxide, chemically reduced graphene oxide (RGO) and thermally reduced graphene oxide (TRGO) with different concentrations (0.1, 0.5 and 1 g/L) were incorporated in the copper matrix. The surface-mechanical and electrical properties of the developed coatings were investigated for possible electrical contacts applications. The deposition process was carried out at a pH value of 1 ± 0.02, which was sufficiently below the isoelectric point of RGO and TRGO to avoid possible agglomeration during deposition. A structural change of the synthesized specimens and the presence of GO in the composite coating were demonstrated from Raman spectra characterization. X-ray photo electron spectroscopy of some specific specimens (RGO, TRGO and Cu-0.5 g/L TRGO) was carried out to study the elemental composition, chemical state and electronic state of the elements present. Improvement of mechanical and electrical properties was clearly evident due to dispersion hardening caused by uniform dispersion of second-phase GOs. Cu–TRGO composite coating shows excellent electrical conductivity as compared to GO- and RGO-reinforced composite coatings due to removal of oxygen-containing groups after thermal reduction process.

Oxidation studies of Co-Cr-Cu-Fe-Ni-SiX=(0,0.3,0.6,0.9) high entropy alloys (HEA) at 600, 700 and 800 °C for 30 h are performed in the present work. Isothermal oxidation confirmed that the oxidation resistance of Co-Cr-Cu-Fe-Ni-SiX=(0,0.3,0.6,0.9 ) high entropy alloy increases with Silicon (Si) content up to 0.6%, beyond that it decreases. Oxidation rate kinetics study of all the alloys at the three designated test temperature represented the typical cubic curve. X-ray diffraction (XRD) analysis revealed the evolution of Cu oxide (CuO) along with existing phases in all the HEA samples. Microstructural observation after oxidation test exhibited an increase in oxide formation with the oxidation temperature. To comprehend the kinetics of oxidation more clearly, Arrhenius plots were drawn for all the HEA samples and activation energies are calculated.

Objective: To review the effects of tomato product supplementation, containing lycopene, on biomarkers of oxidative stress and carcinogenesis in human clinical trials. Results: Supplementation of tomato products, containing lycopene, has been shown to lower biomarkers of oxidative stress and carcinogenesis in healthy and type II diabetic patients, and prostate cancer patients, respectively. Processed tomato products like tomato juice, tomato paste, tomato puree, tomato ketchup and tomato oleoresin have been shown to provide bioavailable sources of lycopene, with consequent increases in plasma lycopene levels versus baseline. Dietary fats enhance this process and should be consumed together with food sources of lycopene. The mechanisms of action involve protection of plasma lipoproteins, lymphocyte DNA and serum proteins against oxidative damage, and anticarcinogenic effects, including reduction of prostate-specific antigen, upregulation of connexin expression and overall decrease in prostate tumor aggressiveness. There is limited in vivo data on the health benefits of lycopene alone. Most of the clinical trials with tomato products suggest a synergistic action of lycopene with other nutrients, in lowering biomarkers of oxidative stress and carcinogenesis. Conclusions: Consumption of processed tomato products, containing lycopene, is of significant health benefit and can be attributed to a combination of naturally occurring nutrients in tomatoes. Lycopene, the main tomato carotenoid, contributes to this effect, but its role per se remains to be investigated.

The shear strength of rock joints plays a key role in controlling rock mass behaviors. As the ongoing process of weathering in nature brings about intricate changes to rocks, shear behavior of rock joints is also influenced by the degree of weathering of the joint surface materials. However, efficiencies of the common and simple JRC-JCS models existing in the literature in predicting the shear strength with reference to weathering grades of rock joints does not seem to have been evaluated. In this study, a modification of the JRC-JCS model was proposed based on a total of 119 direct shear tests performed on natural, planner, unfilled and weathered (i.e. grades II and III) joints of granite and quartzite from India. Subsequently, the efficacies of the proposed criterion and three other apparently useful JRC-JCS models including Barton’s model were evaluated in estimating the peak shear strength of rock joints with reference to a particular weathering grade as well as in regard to different weathering grades considered together. For such evaluation, the peak shear strength values with reference to weathering grades of the joint surfaces obtained from the direct shear tests of this study were considered. Additionally, the peak shear strength data for weathered non-planar granitic joints (i.e. grades I, II and III) existing in the literature was also taken into account. From the statistical comparison, it became evident that the shear strength criterion proposed in this study is significantly more efficient than the other considered criteria. The apparent superiority of the proposed criterion over the three other considered JRC-JCS models could be attributed to very different types of joint surfaces investigated in this study with reference to weathering grades and rock types.

Ni–W alloy coatings have various applications because they are capable of replacing hard chromium coatings due to their corrosion, oxidation, wear, and hardness properties. Moreover, these alloys demonstrate excellent mechanical and thermal stability at high temperatures leading to possible specialized applications of such coatings. In this study, the effect of pulse frequency and current density on the structure and properties of electrodeposited Ni–W coating were investigated. Pulse electro-co-deposition technique was employed to synthesize Ni–W alloy coatings by varying pulse frequency and current density. The deposition process was performed in the newly established deposition bath that does not contain surfactants and stress-relieving agents. The Ni–W-coated samples were evaluated to determine surface mechanical (microhardness and wear) and electrochemical properties. Phase formation, microstructure, and compositional analysis of Ni–W alloy coatings were examined by XRD, SEM, and EDS, respectively. Microstructure examination revealed that morphology of the coating varied with pulsed frequency and current density. An increase in the current density at fixed pulse frequency improved the surface mechanical properties (hardness and wear properties) owing to higher W content, fine, and dense structure of the coating. The maximum hardness (920 HV) and wear resistance were observed in the Ni–W coating that was obtained at the current density of 60 mA cm−2 and frequency of 2 kHz. Electrochemical polarization test and EIS study carried out in 3.5 wt pct NaCl solution reveal that a decrease in corrosion resistance of the coating is due to finer morphology or strained matrix whereas higher W content improves the corrosion resistance.

A subset of glutamate receptors that are specifically sensitive to the glutamate analog N -methyl- D -aspartate (NMDA) are molecular coincidence detectors, necessary for activity-dependent processes of neurodevelopment and in sensory and cognitive functions. The activity of these receptors is modulated by the endogenous amino acid D -serine, but the extent to which D -serine is necessary for the normal development and function of the mammalian nervous system was previously unknown. Decreased signaling at NMDA receptors has been implicated in the pathophysiology of schizophrenia based on pharmacological evidence, and several human genes related to D -serine metabolism and glutamatergic neurotransmission have been implicated in the etiology of schizophrenia. Here we show that genetically modified mice lacking the ability to produce D -serine endogenously have profoundly altered glutamatergic neurotransmission, and relatively subtle but significant behavioral abnormalities that reflect hyperactivity and impaired spatial memory, and that are consistent with elevated anxiety.