Basic Probe Research Articles

Influence of ultrasonic-assisted abrasive peening treatment on Ti-6Al-4V and OFHC Cu alloys

Numerous peening techniques exist can effectively modify the sample surface, although at the expense of severe surface damage and high capital investment. Ultrasonic-assisted abrasive peening (UAP) is a superior option that can peen the surface with minimal deterioration using a basic probe sonicator. In this paper, the influence of UAP parameters (i.e., beaker size and fluid volume, power, abrasive concentration, and time) on the surface integrity of Ti-6Al-4V and OFHC Cu was studied experimentally. The process is capable of inducing significant compressive residual stress at around 84 % and 280 % of yield strength in Ti-6Al-4V and OFHC Cu, respectively. The study examined the change in surface roughness (ΔRa), ΔRa = roughness before - roughness after peening. As peening intensities increase, ΔRa reaches +7 nm, showing a surface finish in Ti-6Al-4V. The dislocations density calculated from the Williamson-Hall equation exhibited a 20 and 4.5-fold augmentation in peened Ti-6Al-4V and OFHC Cu in comparison to their un-peened state. EBSD analysis revealed a 28 % and 40 % reduction in grain size in Ti-6Al-4V and OFHC Cu after peening. This work validates the efficacy of the proposed UAP technique and supports the selection of optimized UAP process parameters.

A Study on Reducing Traffic Congestion in the Roadside Unit for Autonomous Vehicles Using BSM and PVD

With the rapid advancement of autonomous vehicles reshaping urban transportation, the importance of innovative traffic management solutions has escalated. This research addresses these challenges through the deployment of roadside units (RSUs), aimed at enhancing traffic flow and safety within the autonomous driving era. Our research, conducted in diverse road settings such as straight and traffic circle roads, delves into the RSUs’ capacity to diminish traffic density and alleviate congestion. Employing vehicle-to-infrastructure communication, we can scrutinize its essential role in navigating autonomous vehicles, incorporating basic safety messages (BSMs) and probe vehicle data (PVD) to accurately monitor vehicle presence and status. This paper presupposes the connectivity of all vehicles, contemplating the integration of on-board units or on-board diagnostics in legacy vehicles to extend connectivity, albeit this aspect falls beyond the work’s current ambit. Our detailed experiments on two types of roads demonstrate that vehicle behavior is significantly impacted when density reaches critical thresholds of 3.57% on straight roads and 34.41% on traffic circle roads. However, it is important to note that the identified threshold values are not absolute. In our experiments, these thresholds represent points at which the behavior of one vehicle begins to significantly impact the flow of two or more vehicles. At these levels, we propose that RSUs intervene to mitigate traffic issues by implementing measures such as prohibiting lane changes or restricting entry to traffic circles. We propose a new message set in PVD for RSUs: road balance. Using this message, RSUs can negotiate between vehicles. This approach underscores the RSUs’ capability to actively manage traffic flow and prevent congestion, highlighting their critical role in maintaining optimal traffic conditions and enhancing road safety.

Promoted catalytic performance of sugarcane bagasse ash supported by γ‐alumina as efficient, stable, and ecofriendly catalyst for dehydration of methanol to dimethyl ether

AbstractThe aim of this study was to use different proportions (1% to 20% by weight) of γ‐alumina to modify sugarcane bagasse ash (SCBA) for the production of dimethyl ether (DME) through the dehydration of methyl alcohol. A simple precipitation method was utilized to fabricate (1–20 wt.%) Al2O3/SCBA catalysts. X‐ray fluorescence, X‐ray diffraction, Fourier‐transform infrared spectroscopy, transmission electron microscopy, and N2 sorption were used to explore the structural, spectroscopic, morphological, and textural features. The XRD pattern of Al2O3/SCBA catalysts showed a new peak that corresponded to the formation of γ‐Al2O3. In addition, the average crystallite sizes of pure SCBA and 10% and 20%Al2O3/SCBA catalysts were calculated and found to be 20.1, 21.6, and 22.6 nm, respectively. To evaluate the acidity of these catalysts, the dehydration of isopropyl alcohol and the chemisorption of basic probe molecules were employed. The acidity test results displayed that these catalysts have weak to moderate acidic sites. The 10% Al2O3/SCBA catalyst calcined at 400°C showed high efficiency for the conversion of methyl alcohol to DME, attaining 89% conversion with 100% selectivity. This observation can be attributed to the even distribution of active sites and the acid–base equilibrium on the surface. Moreover, its catalytic activity and selectivity remain unchanged over a continuous 2‐week operation without coke formation, demonstrating its extremely high stability. A strong correlation was observed between the catalytic activity and both the surface area and acidity of the catalysts.

Practical examination of flow rate effects and influence of the stationary phase water layer on peak shape and retention in Hydrophilic Interaction Liquid Chromatography.

The effect of flow velocity on retention and peak shape of neutral, acidic and basic probe compounds was studied using seven different UHPLC hydrophilic interaction chromatography (HILIC) columns. Surprisingly on some columns, the retention factor k was found to vary somewhat with flow velocity, due to the combined effects of pressure and of frictional heating on retention. The selectivity of different HILIC columns was much greater than typically found with RP columns. The volume of the water layer on the HILIC columns was measured using the toluene exclusion procedure. For the neutral solute uridine, a good correlation was found between the volume of the water layer and retention, indicating the likely domination of a partition mechanism. For the ionogenic solutes, the correlation was generally poor, due to the presence of strong additional mechanisms such as ionic retention and repulsion. Reduced van Deemter plots for uridine showed a negative correlation between the reduced b coefficient and the volume of the water layer, which can be attributed to reduced surface diffusion in this viscous layer. Once again, the behaviour of ionic solutes was complex on some columns making detailed interpretation difficult.

Lewis Acid Probe for Basicity of Sulfide Electrolytes Investigated by 11B Solid-State NMR.

Sulfide-based solid-state lithium-ion batteries (SSLIB) have attracted a lot of interest globally in the past few years for their high safety and high energy density over the traditional lithium-ion batteries. However, sulfide electrolytes (SEs) are moisture-sensitive which pose significant challenges in the material preparation and cell manufacturing. To the best of our knowledge, there is no tool available to probe the types and the strength of the basic sites in sulfide electrolytes, which is crucial for understanding the moisture stability of sulfide electrolytes. Herein, we propose a new spectral probe with the Lewis base indicator BBr3 to probe the strength of Lewis basic sites on various sulfide electrolytes by 11B solid-state NMR spectroscopy (11B-NMR). The active sulfur sites and the corresponding strength of the sulfide electrolytes are successfully evaluated by the proposed Lewis base probe. The probed strength of the active sulfur sites of a sulfide electrolyte is consistent with the results of DFT (density functional theory) calculation and correlated with the H2S generation rate when the electrolyte was exposed in moisture atmosphere. This work paves a new way to investigate the basicity and moisture stability of the sulfide electrolytes.

The catalytic performance of FexMn1-xWO4 as novel wolframite-type nanocatalysts for the selective dehydration of methanol into dimethyl ether

Selective production of dimethyl ether (DME), as a second-generation biofuel, under mild green conditions is still a challenge. Herein, FexMn1-xWO4 wolframite-type materials were proposed for the first time as efficient, selective, and stable catalysts towards methanol dehydration into DME. A simple one-step co-precipitation approach was used to fabricate the nanocomposites, and their catalytic performances were evaluated in comparison to earlier studies and to the commercial γ-Al2O3 in terms of activity. The catalysts’ structure, morphology, and porosity were identified by XRD, XPS, FTIR, TEM, and N2-sorption analyses. Results of XRD and XPS confirmed the successful synthesis of FexMn1-xWO4 catalysts. Acidity of these nanocomposites were greatly influenced with the variation in x-value, calcination temperature, and doping with SO42−. The Brønsted characters of the acid sites and their weak and medium strength were investigated from PY-FTIR, chemisorption of basic probes and pyridine-TPD. The variation of the catalytic activities of these nanocomposites was strongly correlated to the variation in the catalyst acidity. The catalytic activity results indicated that Fe0.5Mn0.5WO4 catalyst calcined at 500 °C and modified with 5 wt.% of SO42- is the most effective nanocomposite with conversion values of 86 and 90% at reaction temperatures of 250 and 275 °C, respectively and all of 100% DME selectivity. The remarkable enhancement in the catalytic activity due to the doping with SO42- is attributed to the inductive effect of S = O group created on the catalyst surface. This nanocomposite could be regenerated many times with nearly the same efficiency and selectivity. Moreover, it offered a long-term stability (∼120 h) towards DME production.

An Outlook on the Status of Security Performance in The Light of Intelligence

Abstract: An outlook on the status of security performance in light of intelligence focuses on the business aspects and needs of organizations. The security plan needs to be integrated with the business and should be developed in collaboration with different groups within an organization. Organizations need to have a culture that embraces security and intelligence. Security performance is one of the top concerns of modern businesses. Companies must look at the underlying causes of their problems in order to fix them. A good cybersecurity posture is often measured by a lack of data breaches. Lack of specific metrics, however, may be an indication that a company does not have a strategic mindset. Attacks and malfunctions are extremely costly. Detection involves identifying suspicious behaviors and alerting the appropriate personnel. An important challenge in detecting suspicious activity is finding the right balance between false alarms and coverage. An effective security program must be able to mitigate attacks while reducing false alarms. The growing reliance on artificial intelligence (AI) is creating a new kind of cybervulnerability. Developers often overlook AI security, leaving it open to attack by adversaries. Attacks can take the form of basic manipulations and probes or adversarial AI. As the number of computer systems increases, so do the risks they pose to the security of data and systems. This article examines the importance of security performance, the role of the cloud, machine learning-based security models, and incident response. We also look at the importance of a security model that incorporates intelligence. Finally, this report also identifies five critical areas in which Intelligence attacks pose a high risk to organizations.

Basic Fluorescent Protonation-Type pH Probe Sensitive to Small ΔpKa of Methanol and Ethanol

An optical pH probe is a simple and effective tool for determining an accurate pH value in its localized area. However, basic pH probes with pKBH+ values above 8 have rarely been reported, although many components with high pKa such as arginine play important roles in vivo. Herein, we introduce novel colorimetric and fluorescent basic probes 1-5, which are designed using push-pull-type aminoquinoline and aminobenzoquinoline fluorophores, with pKBH+ values ranging from 8.4 to 9.9. After the basicity of the remarkably sensitive basic probe 4 was tuned, it was able to successfully distinguish between the pKa values of MeOH (15.5) and EtOH (15.9), thus displaying selective protonation and fluorescence enhancement in MeOH over EtOH. Our pH probes can be used to detect MeOH poisoning in commercial EtOH products such as hand sanitizers, providing an effective solution to this problem observed during the COVID-19 pandemic.

Relationship between nutritional status and periodontal disease among pregnant women attending Abakpa Nike health center, Enugu, Enugu state, Nigeria

Pregnancy is a period during which one or more offspring develop inside the womb of a woman. It lasts for a period of nine months comprising of three trimesters. Obesity has been proven to have an adverse influence on the effect of pregnancy hormones on the periodontal tissue. It produces inflammatory cytokines which aggregates the systemic inflammatory conditions exacerbated by pregnancy hormones which predisposes the periodontuim to periodontal disease. The aim of the study is to evaluate the relationship between nutritional status and periodontal disease among pregnant women attending Abakpa Nike Health Center. A sample size of 70 pregnant women attending Abakpa Nike Health Center, Enugu was randomly selected for this study. Their nutritional status was determined using the Body Mass Index analysis and their periodontal health was also examined using basic periodontal probe and mouth mirror. It was discovered that 42 (60%) of the pregnant women were diagnosed with periodontal diseases and 22 (52.4%) of the pregnant women diagnosed with periodontal disease presented with gingivitis. The study also showed that 34 (76%) of the pregnant women in their second trimester and 6 (50%) of the women in their third trimester were diagnosed with periodontal disease. It also revealed that majority 29 (69.0%) of the pregnant women diagnosed with periodontal disease had unhealthy body weight. This shows that there is a significant relationship between nutritional status and periodontal disease among pregnant women attending Abakpa Nike Health Center, Enugu. Therefore this study recommend that sensitization programmes should be included in the ante natal programmes to educate the pregnant women on how to maintain a healthy body balance and improve oral hygiene especially during pregnancy.

Cation-doping strategies for tuning of zirconia acid-base properties.

The role of Y-, Ca- and Ce-doping of cubic zirconia (c-ZrO2) (111) surface on its acidity, basicity and the interplay between surface acid–base pairs is investigated by computational methods. The most stable surface structures for this investigation were initially determined based on previous studies of Y-doped c-ZrO2 (111) and by a detailed exploration of the most stable configuration for Ca-doped c-ZrO2 (111) and Ce-doped c-ZrO2 (111). Next, surface mapping by basic probe molecules (NH3 and pyridine) revealed a general reduction of the acidity of the surface sites, although a few exceptions were observed for zirconium ions at next nearest neighbour (NNN) positions to the oxygen vacancy and at the nearest neighbour (NN) position to the dopants. Adsorption of CO2 over basic sites revealed a cooperative interplay between acid–base groups. In this case, the overall effect observed was the decrease of the calculated adsorption energies when compared with the pristine surface. Moreover, spontaneous formation of η3-CO2 systems from initial η2-CO2 configurations indicates a decrease in the required energy for forming oxygen vacancies in the doped ZrO2 systems at NNN positions or further away from the existing vacancy site.

A multifunctional basic pH indicator probe for distinguishable detection of Co2+, Cu2+ and Zn2+ with its utility in mitotracking and monitoring cytoplasmic viscosity in apoptotic cells.

Metal ions such as Co2+, Cu2+ and Zn2+ have extensive applications in biological and industrial realms, but the toxicity caused by these ions poses a serious threat to mankind. However, there is no report in the literature on the development of a chemosensor for distinguishable detection of these toxic ions. Addressing this challenge, a multifunctional probe as a basic pH indicator with both colorimetric and fluorescence turn-on responses has been reported. The probe selectively discriminates Co2+, Cu2+ and Zn2+ ions with brown, dark yellow and greenish yellow colors, respectively, in DMF : water (9 : 1 v/v, HEPES 10 mM). Additionally, a fluorescence turn-on response specific to Zn2+ has also been observed. The sensing mechanism has been explored using UV-Vis, fluorescence spectroscopy and 1H NMR titration and confirmed with computational results. The inhibition of CN isomerization and excited state intramolecular proton transfer (ESIPT) along with chelation enhanced fluorescence emission (CHEF) result in fluorescence enhancement with Zn2+. Job's plot and HRMS spectra confirm a 1 : 1 (L : M) stoichiometry between the probe and metal ions. The probe is able to exhibit excellent viscochromism in DMF : glycerol medium. Live cell imaging on SiHa cells has been successfully performed for intra-cellular detection of Zn2+ at basic pH. Furthermore, the probe displays its utility in mitotracking and monitoring cytoplasmic viscosity changes in SiHa cells. It is efficiently used to recognize the apoptosis process by displaying an enhancement in fluorescence intensity from cancerous SiHa cells to apoptotic cells.

Vanadium-substituted polycationic Al-oxo cluster in a porous ionic crystal exhibiting Lewis acidity.

Herein we present the first example of a vanadium-substituted δ-Keggin Al13-based (Al28V4) porous Ionic crystal (PIC) (Al28V4-PW9V3). Structural and theoretical studies suggested that Al28V4 may exhibit Lewis acidity, which was confirmed by acetalization reaction with Al28V4-PW9V3 as a solid catalyst and investigations with pyridine or 2,6-lutidine as basic probe molecules. A comparative study with the δ-Keggin Al13 monomer based PIC indicated that the vanadium-substitution gave rise to the Lewis acidity.

Soft-templating routes for the synthesis of mesoporous tantalum phosphates and their catalytic activity in glycerol dehydration and carbonylation reactions

The craftsmanship in catalyst synthesis becomes very fascinating when the catalytic activity of the material can be enhanced by tuning the synthesis conditions. The underlying fundamental strategy is presented here in tailoring the structural and chemical behavior of the tantalum phosphates (TaP) by using different structure directing agents (SDAs). We found that by employing appropriate template assisted pathway it is possible to tune the morphology and the nature of active sites of TaP. The synthesised catalysts were comprehensively characterised by N2-physisorption, FESEM, HRTEM, powder XRD, FTIR, UV–Vis, XPS, NH3 and CO2-TPD, Py-adsorbed IR, elemental analysis and 31P{1H} NMR techniques. The FESEM and HRTEM analysis revealed the transition of non-spherical to rod-shaped particles upon moving from ionic to non-ionic surfactants. The TPD and Py-IR studies revealed the variation in amount, strength and nature of the acidic-basic sites with the change in SDA. The resultant TaP catalysts were investigated for gas phase glycerol dehydration to acrolein and liquid phase glycerol carbonylation to glycerol carbonate. Among these catalysts, TaPC synthesized by using CTAB as SDA exhibited promising catalytic activity in both gas and liquid phase reactions. The active site elucidation in TaPC catalyst was done by adopting basic probe molecule 2,6-lutidine. The deactivation kinetic study was carried out for the gas phase glycerol dehydration reaction. The investigation on the spent catalyst showed it is stable under both gas-phase and liquid-phase reaction conditions. This study hence provides a pathway for analytical architecture and construction of highly efficient TaP catalysts for glycerol transformation reactions.

Internal jugular vein ultrasound in patients with chronic congestive heart failure

Abstract Background Bedside assessment of intravascular volume in patients with chronic congestive heart failure (CHF) is often difficult. Under- and over-diuresis are common causes of morbidity and readmissions in these patients. Purpose We hypothesized that ultrasound assessment of the internal jugular vein would be easier and more reproducible than clinically assessing jugular venous pressure (JVP). Our goal was to create a bedside test that would be simpler to learn than inferior vena cava (IVC) assessment and easier to perform in obese patients. Methods Adults with HF (n=53, 52% men, mean age 65 years, mean BMI 29.6 kg/m2, mean LVEF 44%) scheduled for right heart catheterization (RHC) had an ultrasound of their right internal jugular (RIJ) vein performed immediately prior. Cross-sectional area of RIJ was measured during normal breathing with patients at 90 and 45 degrees recumbency and was indexed by height (RIJI). JVP was also assessed clinically. Results were compared to right atrial pressure (RAP) measured by RHC. Operators were blinded to RHC results and vice versa. Results JVP was correctly assessed clinically in only 43%. RIJI at 90 and 45 degrees were significantly larger in patients with elevated RAP compared to euvolemic patients (Table). At 90 degrees, RIJI of >15 predicted a RAP of >10 mmHg with 68% sensitivity and 72% specificity. At 45 degrees, RIJI of >10 predicted a RAP of >10 mmHg with 94% sensitivity and a negative predictive value of 80% (Table). Simply being able to see the RIJ at 90 degrees (n=34) had an 82.4% positive predictive value for elevated RAP. IVC data could not be obtained on 23% of patients due to body habitus or inability to lay flat. Conclusion Ultrasonographic RIJI is more accurate than clinical assessment in patients with CHF and can be accurately performed even in obese patients. It requires only a basic linear ultrasound probe and was easily performed by clinicians at various stages of training with reproducible results. With the increased availability of bedside ultrasound in clinical practice, it is a feasible method of evaluating chronic CHF patients. Funding Acknowledgement Type of funding sources: None.

Hystorian: A processing tool for scanning probe microscopy and other n-dimensional datasets

Research in materials science increasingly depends on the correlation of information from multiple characterisation techniques, acquired in ever larger datasets. Efficient methods of processing and storing these complex datasets are therefore crucial. Reliably keeping track of data processing is also essential to conform with the goals of open science. Here, we introduce Hystorian, a generic materials science data analysis Python package built at its core to improve the traceability, reproducibility, and archival ability of data processing. Proprietary data formats are converted into open hierarchical data format (HDF5) files, with both datasets and subsequent workflows automatically stored into a single location, thus allowing easy management of multiple data types. At present, Hystorian provides a basic scanning probe microscopy and x-ray diffraction analysis toolkit, and is readily extensible to suit user needs. It is also able to wrap over any existing processing functions, making it easy to append in an extant workflow.

A Guide to Doppler Ultrasound Analysis of the Face in Cosmetic Medicine. Part 1: Standard Positions.

Interest in Doppler ultrasound (DUS) analysis of the face has grown in cosmetic medicine, in particular for injectable fillers. When dealing with complications, DUS has the advantage of easily visualizing the filler and identifying the problem in relation to the patient's anatomy. When working with hyaluronic acid filler, ultrasound-guided injections with hyaluronidase can precisely target the problem. In addition, DUS can be used to study the anatomy of a patient, specifically to prevent intravascular injections. We predict that in a few years' time DUS will become standard equipment in the offices of cosmetic doctors. We discuss the basics of ultrasound imaging of different tissues with the concomitant terminology. With the use of 7 basic DUS probe positions, key anatomic reference points can be easily found. From these, all relevant anatomic structures in the face can be observed and analyzed. With some practice, physicians will ultimately be able to acquire a complete 3-dimensional mental image of a patient's face.

Fluorescent Membrane Tension Probes for Early Endosomes

AbstractFluorescent flipper probes have been introduced recently to image membrane tension in live cells, and strategies to target these probes to specific membranes are emerging. In this context, early endosome (EE) targeting without the use of protein engineering is especially appealing because it translates into a fascinating transport problem. Weakly basic probes, commonly used to track the inside of acidic late endosomes and lysosomes, are poorly retained in EE because they are sufficiently neutralized in weakly acidic EE, thus able to diffuse out. Here, we disclose a rational strategy to target EE using a substituted benzylamine with a higher pKa value as a head group of the flipper probe. The resulting EE flippers are validated for preserved mechanosensitivity, ready for use in biology, particularly to elucidate the mechanics of endocytosis.

Fluorescent Membrane Tension Probes for Early Endosomes.

Fluorescent flipper probes have been introduced recently to image membrane tension in live cells, and strategies to target these probes to specific membranes are emerging. In this context, early endosome (EE) targeting without the use of protein engineering is especially appealing because it translates into a fascinating transport problem. Weakly basic probes, commonly used to track the inside of acidic late endosomes and lysosomes, are poorly retained in EE because they are sufficiently neutralized in weakly acidic EE, thus able to diffuse out. Here, we disclose a rational strategy to target EE using a substituted benzylamine with a higher pKa value as a head group of the flipper probe. The resulting EE flippers are validated for preserved mechanosensitivity, ready for use in biology, particularly to elucidate the mechanics of endocytosis.

Photoacoustic hygrometer for icing wind tunnel water content measurement: design, analysis, and intercomparison

Abstract. This work describes the latest design, calibration and application of a near-infrared laser diode-based photoacoustic (PA) hygrometer developed for total water content measurement in simulated atmospheric freezing precipitation and high ice water content conditions with relevance in fundamental icing research, aviation testing, and certification. The single-wavelength and single-pass PA absorption cell is calibrated for molar water vapor fractions with a two-pressure humidity generator integrated into the instrument. Laboratory calibration showed an estimated measurement accuracy better than 3.3 % in the water vapor mole fraction range of 510–12 360 ppm (5 % from 250–21 200 ppm) with a theoretical limit of detection (3σ) of 3.2 ppm. The hygrometer is examined in combination with a basic isokinetic evaporator probe (IKP) and sampling system designed for icing wind tunnel applications, for which a general description of total condensed water content (CWC) measurements and uncertainties are presented. Despite the current limitation of the IKP to a hydrometeor mass flux below 90 gm-2s-1, a CWC measurement accuracy better than 20 % is achieved by the instrument above a CWC of 0.14 g m−3 in cold air (−30 ∘C) with suitable background humidity measurement. Results of a comparison to the Cranfield University IKP instrument in freezing drizzle and rain show a CWC agreement of the two instruments within 20 %, which demonstrates the potential of PA hygrometers for water content measurement in atmospheric icing conditions.

Melanin system composition analyzed by XPS depth profiling

The melanins are a class of natural pigments ubiquitous throughout the biosphere. These pigments are gaining significant attention as advanced materials due to their biocompatibility, optical and electrical properties. The most common form of melanin, eumelanin, has a well-known problem of insolubility in most common solvents. The insolubility has made standard chemical analysis challenging, leading to researchers opting to use X-Ray photoelectron spectroscopy (XPS). However, standard XPS used on melanins and related materials have been limited to being a surface technique, and hence reported values to date may not reflect the bulk. In this work, we have investigated with XPS depth-profiling method the chemical information of the surface and the bulk of powder and thin-films of eumelanin and several melanin derivatives. These latter derivatives are modified melanins designed to overcome the insolubility of the standard systems. Our result indicates that there are only few differences in the chemical composition of the melanin chemical structure between the surface and bulk, for either the powder of film samples. Our results show that a basic surface probe is sufficient to obtain an accurate elemental composition for basic melanin samples. As such, our analysis indicates that XPS characterization is an important characterization of polyindolequinone systems in general such as the melanins and polydopamines.