Microbially influenced corrosion communities associated with fuel-grade ethanol environments.

Microbially influenced corrosion (MIC) is a costly problem that impacts hydrocarbon production and processing equipment, water distribution systems, ships, railcars, and other types of metallic infrastructure. In particular, MIC is known to cause considerable damage to hydrocarbon fuel infrastructure including production, transportation, and storage systems, often times with catastrophic environmental contamination results. As the production and use of alternative fuels such as fuel-grade ethanol (FGE) increase, it is important to consider MIC of engineered materials exposed to these "newer fuels" as they enter existing infrastructure. Reports of suspected MIC in systems handling FGE and water prompted an investigation of the microbial diversity associated with these environments. Small subunit ribosomal RNA gene pyrosequencing surveys indicate that acetic-acid-producing bacteria (Acetobacter spp. and Gluconacetobacter spp.) are prevalent in environments exposed to FGE and water. Other microbes previously implicated in corrosion, such as sulfate-reducing bacteria and methanogens, were also identified. In addition, acetic-acid-producing microbes and sulfate-reducing microbes were cultivated from sampled environments containing FGE and water. Results indicate that complex microbial communities form in these FGE environments and could cause significant MIC-related damage that may be difficult to control. How to better manage these microbial communities will be a defining aspect of improving mitigation of global infrastructure corrosion.

A Case of Steroid-Induced Gastric Perforation in a Ten-Year-Old Child.

Gastric perforation is a rare yet critical clinical disorder that demands prompt medical attention. Gastric ulcers often manifest on the anterior wall of the stomach, underscoring the importance of early detection for an improved prognosis. This study delves into a specific case, shedding light on a 10-year-old male child diagnosed with steroid-induced gastric perforation. The diagnosis was established through a meticulous examination of the clinical history and a plain abdominal X-ray, culminating in a timely and decisive surgical intervention for repair.

Prevalence and Risk Associated With Bladder Injuries During Caesarean Section in a Secondary Care Hospital.

Introduction Bladder injury during caesarean section (CS) is not uncommon. Various factors increase the risk of bladder injury during CS, including prolonged labor with bladder distension, pregnancy with a scarred uterus, suspected intra-abdominal adhesions, distorted local anatomy, cesarean hysterectomy, and an increasing number of previous CS. Vigilant preoperative assessment and surgical precision are essential to mitigate these risks and ensure optimal outcomes for mother and child. Objectives To find out the prevalence and risk factors associated with bladder injuries during caesarean section. Methodology Hospital-based retrospective record review of 3600 pregnant women who had undergone cesarean section during the period January 2015 to December 2023 were included in the study. Data was analyzed using SPSS software, version 22 (trial version) (IBM Corp., Armonk, NY). The Chi-square test and Fisher's exact test were used. Ethical clearance was obtained from the Institutional Ethics Committee at Tata Main Hospital Noamundi (approval number NI/CMO/26/24). Result Bladder injury prevalence was reported to be 1.1%. Bladder injuries were significantly (p<0.0001) more among the CS cases with underlined complications as compared to CS cases without any underlined complications. Repeat CSs were found to have a significantly (p<0.001) higher proportion of bladder injuries compared to primary CS.  Conclusion Bladder injuries during cesarean section are a significant concern. The risk factors identified, such as the number of previous cesarean sections and complications during pregnancy, highlight the importance of careful preoperative assessment and surgical precision to prevent such injuries.

Cellular response of titanium and its alloys as implants.

The cellular response of osteocytes to commercially pure titanium (α) and its alloys (α + ß and ß) has been tested in a culture media, and the results have been supplemented by analyses from various techniques such as inductively coupled plasma atomic emission spectroscopic (ICP-AES) analysis, X-ray photoemission spectroscopy (XPS), scanning electron microscopy (SEM), metallography, and electrochemical measurements. These results have been correlated with respect to the presence of various alloying elements in these alloys to qualify them for human application. The newer ß alloys have been examined for their potential use as implants. These results serve as a preliminary baseline to characterize the best alloy system for a comprehensive long-term investigation.

The effect of magnetron pulsing on the structure and properties of tribological Cr-Al-N coatings.

The paper will discuss the effect of pulsing single or two unbalanced magnetrons in a closed magnetic field configuration on the structure and properties of tribological Cr-Al-N coatings. Nanocrystalline Cr-Al-N coatings were reactively deposited from Cr and Al elemental targets using two unbalanced magnetrons, which were powered in both dc, pulsing only Al target and asynchronously pulsing both Cr and Al targets at 100 kHz and 50% duty cycle conditions. The ion energy distributions of these deposition and pulsing conditions were characterized using a Hiden Electrostatic QuadruPole Plasma Analyzer. It was found that pulsing two magnetrons asynchronously at 100 kHz and 50% duty cycle produced higher ion energies and significant increased ion fluxes than pulsing none or pulsing only one (Al) target. The structure and properties of Cr-Al-N coatings synthesized under different dc and pulsing conditions were investigated using X-ray diffraction, scanning electron microscopy, nanoindentation and ball-on-disk wear test, and were correlated with the effects of ion energies and ion flux regimes observed in the plasma diagnostics. The advantages of using pulsed magnetron sputtering producing different energetic ion regimes to enhance the ion bombardment on the growing films and therefore achieving the improved density, refinement of grain size and properties are illustrated.

Effect of povidone-iodine addition on the corrosion behavior of cp-Ti in normal saline.

The effect of various concentrations of povidone-iodine (PI) on the corrosion behavior of a commercially pure titanium alloy (Ti-1) has been investigated in normal saline solution to simulate the povidone-iodine addition in an oral environment. The open circuit potential, electrochemical impedance spectroscopy and potentiodynamic polarization measurements have been used to characterize the electrochemical phenomena occurring on the alloy surface. The open circuit potential values for Ti-1 in various concentrations of PI shift considerably towards noble direction as compared to pure normal saline. In the potentiodynamic polarization curve for Ti-1 in various solutions, the cathodic current density has increased for all concentrations of PI and the anodic current density has decreased. Only the 0.1% PI concentration is able to inhibit corrosion of Ti-1 in normal saline and the other higher concentrations studied, accelerate corrosion. The EIS data for Ti-1 in normal saline and in various concentrations of PI follows a one time constant circuit, suggesting the formation of a single passive film on Ti-1 which is not altered by the addition of PI to normal saline.

Removal of oil from ferrous grinding swarf of automobile industry by aqueous washing process.

This research focused on the recovery of valuable materials from ferrous grinding swarf. We received the sample from the automobile industry. The sample has consisted of approximately 20 wt% moisture and 80 wt% residue (oil and soild). The chemical composition of the oven-dried sample was approximately 87 wt% iron. In this study, aqueous washing process for oil removal from ferrous grinding swarf was investigated with two different commercial reagents, Micro-90 and Detergent 8. Three different amounts of solids (2, 3, and 4 g) were mixed with 20 mL of diluted reagents for the aqueous washing. In the Micro-90 solution, about 80% of the oil was removed after three washing cycles at a solids content less than 3 g/20 mL. On the other hand, when using Detergent 8, 100% oil was removed after three washing cycles at a solids content of less than 3 g/20 mL. Pulp density was an important factor in determining oil removal efficiency. For the scale-up experiment, different washing methods such as ultrasonication and overhead stirrer were examined. The preliminary reuse test of the Detergent 8 solution was also conducted for the feasibility of the aqueous washing process.

The development of a nanostructured, graded multilayer Cr-CrxNy-Cr1-xAlxN coating produced by pulsed closed field unbalanced magnetron sputtering (P-CFUBMS) for use in aluminum pressure die casting dies.

The main objective of this research is to design an optimized 'coating system' that extends die life by minimizing premature die failure. The concept of the multilayer coating system with desired combinations of different kinds of single-layer coatings was introduced. A pulsed closed field unbalanced magnetron sputtering (P-CFUBMS) deposition system has been used to deposit Cr-CrxNy-Cr1-xAlxN compositionally graded multilayer coating structures. In this study, three power law scenarios have been adopted to vary the aluminum concentration in the graded Cr1-xAlxN layer: (i) p = 1, the aluminum concentration was increased linearly in the Cr1-xAlxN layer. (ii) p = 0.2, the Cr1-xAlxN layer is an aluminum-rich graded layer, and (iii) p = 2, the Cr1-xAlxN layer is a chromium-rich graded layer. It was found that all the graded coatings exhibit lower residual stress and higher adhesion strength than the homogeneous Cr1-xAlxN (x = 0.585) film. However, different power law grading architectures have significant influence on the hardness and wear resistance of the films. When p = 2 and p = 1, the graded films exhibited relatively low hardness values (24 and 26 GPa respectively) and high COF (0.55 to 0.60). When p = 0.2 the graded film exhibited both high hardness (34 GPa) and good wear resistance (COF = 0.45) due to the structural consistency in the graded zone. The paper discusses the correlation between the pulsing parameters and coating architecture with the resulting nanostructure and tribological properties of this Cr-CrxNy-Cr1-xAlxN coating system.

Processing, structure, and properties of nanostructured multifunctional tribological coatings.

Nanostructured, nanocomposite binary (TiC-a:C), ternary (Cr-Al-N), quaternary (Ti-B-C-N) and quinternary (Ti-Si-B-C-N) multicomponent films have been deposited using unbalanced magnetron sputtering (UBMS) and closed field unbalanced magnetron sputtering (CFUBMS) from both elemental and composite targets. Approaches to control the film chemistry, volume fraction and size of the multicomponent species, and pulsed ion energy (ion flux) bombardment to tailor the structure and properties of the films for specific tribological applications, e.g., low friction coefficient and low wear rate, are emphasized. The synthesized films are characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), nanoindentation, and microtribometry. The relationships between processing parameters (pulsed ion energy and ion flux), thin film microstructure, mechanical and tribological properties are being investigated in terms of the nanocrystalline-nanocrystalline and nanocrystalline-amorphous composite thin film systems that are generated. In the Ti-Si-B-C-N films, nanocomposites of solid solutions, e.g., nanosized (Ti,C,N)B2 and Ti(C,N) crystallites are embedded in an amorphous TiSi2 and SiC matrix including some carbon, SiB4, BN, CN(x), TiO2 and B2O3 components. The Ti-Si-B-C-N coating with up to 150 W Si target power exhibited a hardness of about 35 GPa, a high H/E ratio of 0.095, and a low wear rate of from approximately 3 to approximately 10 x 10(-6) mm3/(Nm). In another aspect, using increased ion energy and ion flux, which are generated by pulsing the power of the target(s) in a closed field arrangement, to provide improved ion bombardment on tailoring the structure and properties of TiC-a:C and Cr-Al-N coatings are demonstrated. It was found that highly energetic species (up to hundreds eV) were found in the plasma by pulsing the power of the target(s) during magnetron sputtering. Applying higher pulse frequency and longer reverse time (lower duty cycle) will result in higher ion energy and ion flux in the plasma, which can be utilized to improve the film structure and properties. For example, optimum properties of the TiC-a:C coating were a hardness of 35 to 40 GPa and a COF of 0.2 to 0.22 for moderate maximum ion energies of 70 to 100 eV, and a super high hardness of 41 GPa and low wear rate of 3.41 x 10(-6) mm3N(-1) m(-1) was obtained for Cr-Al-N coatings deposited with a maximum ion energy of 122 eV. These conditions can be achieved by adjusting the pulsing parameters and target voltages. However, the pulsed ion energy together with the applied substrate bias are need to be carefully controlled in order to avoid excessive ion bombardment (e.g., the maximum ion energy is larger than 180 eV in the current study), which will responsible for an increase in point and line defects, and high residual stress in the crystalline structure.