Search

Resonators based on two-dimensional (2D) materials have exceptional properties for application as nanomechanical sensors, which allows them to operate at high frequencies with high sensitivity. However, their performance as nanomechanical sensors is currently limited by their low quality (Q)-factor. Here, we make use of micro-electromechanical systems (MEMS) to apply pure in-plane mechanical strain, enhancing both their resonance frequency and Q-factor. In contrast to earlier work, the 2D material resonators are fabricated on the MEMS actuators without any wet processing steps using a dry-transfer method. A platinum clamp, which is deposited by electron beam-induced deposition, is shown to be effective in fixing the 2D membrane to the MEMS and preventing slippage. By in-plane straining the membranes in a purely mechanical fashion, we increase the tensile energy, thereby diluting dissipation. This way, we show how dissipation dilution can increase the Q -factor of 2D material resonators by 91%. The presented MEMS actuated dissipation dilution method does not only pave the way toward higher Q -factors in resonators based on 2D materials, but also provides a route toward studies of the intrinsic loss mechanisms of 2D materials in the monolayer limit. [ABSTRACT FROM AUTHOR]

Dilution refrigerators are widely used in the fields of condensed matter physics and quantum technology. The condensation-driven dilution refrigerator uses a condenser operating at temperatures below the Still to liquefy the 3He vapor and achieve the circulation of 3He, which has the advantages of compact structure, lightweight, low cost, and low vibration. The published research primarily focuses on the system architecture and performance, and the research and analysis on the thermodynamic cycle are still incomplete. In this paper, the condensation-driven dilution refrigeration cycle has been clarified as a thermally driven refrigeration cycle, and the thermodynamic performances including the figure of merit and thermodynamic perfectibility are investigated. Optimizations have been made to the key components of the previous prototype, and the lowest no-load temperature of 68 mK and a cooling power of 4 μW at 100 mK were achieved. Compared with the previous prototype, the thermodynamic perfectibility of the system increased from 7.63% to 17.83%. The impact of the Still heating strategies on the system was analyzed, and a start-up strategy was proposed to speed up the cooldown process. [ABSTRACT FROM AUTHOR]

The research has examined the effects of CO 2 dilution on ignition characteristics in H 2 /air mixtures. An ignition kernel was initiated by a laser-induced plasma in H 2 /air/CO 2 mixtures with a bulk velocity of 6.5 m/s. An infrared camera was used to measure radiation intensity emitted from H 2 O and ignition probabilities. A high-speed schlieren image system was utilized to measure ignition kernel areas and ignition time. High-speed chemiluminescence was performed to examine OH* intensities. Numerical simulations were conducted using GRI 3.0 mechanisms to calculate reaction rates and laminar flame speeds. The ignition probability is highest for the undiluted mixtures and decreases with increasing the CO 2 dilution fraction at constant adiabatic temperatures. A prolonged ignition time is observed at elevated CO 2 dilution concentrations. Increasing the CO 2 mole fraction decreases the ignition kernel growth, the integrated OH* intensity, and the integrated radiation intensity for each adiabatic temperature. CO 2 reacts with H radicals and decreases the production of OH*, OH, and H 2 O. The CO 2 dilution in the H 2 /air flames significantly contributes to the reduced reaction rate and flame speed, resulting in the low ignition probability. The high ignition probability is found at the large integrated OH* intensity in all cases. The ignition probability is high at the large integrated radiation intensity under the constant adiabatic flame temperatures. The OH* intensity is a critical parameter to estimate the ignition probability in the diluted lean hydrogen flames. • The effects of CO 2 dilution on the ignition process have been studied in lean premixed H 2 /Air flames. • The ignition probability decreases with increasing the CO 2 dilution fraction. • An increase in the CO 2 dilution fraction in the mixtures reduces OH* intensity and radiation intensity emitted from H 2 O. • The presence of CO 2 in the mixtures decreases reaction rates and flame speed. [ABSTRACT FROM AUTHOR]

Biodiversity loss and anthropogenic modifications to species communities are impacting the frequency and magnitude of disease emergence events. These changes may be related through mechanisms in which biodiversity either increases (amplifies) or decreases (dilutes) disease prevalence. Biodiversity effects can be direct, when contacts among competent hosts are replaced by contacts with sink hosts, or indirect through the regulation of host abundances. Here, we introduce a multihost compartmental disease model, weighting host competences by their evolutionary relatedness. Our model simulates host communities with substitutive and additive assembly patterns and frequency‐ and density‐dependent pathogen transmission modes, from which we estimate the community disease outbreak potential R0$$ \left({R}_0\right) $$. Simulations show how differences in phylogenetic structure can switch host communities from diluting to amplifying a disease, even when species richness is unchanged. We additionally show that phylogenetic dilution can occur simultaneously with (classic) amplification through species richness. We illustrate our model using empirical data describing the relationship between phylogenetic distances separating hosts and their likelihood of disease sharing. Our study demonstrates how host evolutionary histories can drive disease dynamics through a phylogenetic dilution effect. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The densities $\rho $ ρ of binary mixtures of 2-(dimethylamino)ethanol and 2-diethylaminoethanol with pyridine were measured over the entire concentration range at 293.15, 303.15 and 313.15 K. The values of excess molar volume, $V_m^E$ V m E , apparent molar volume, ${V_{\varphi ,DMAE}}$ V φ , DMAE and ${V_{\varphi ,DEAE}}$ V φ , DEAE ; partial molar volumes, ${\bar V_{m,1}}$ V ˉ m , 1 and ${\bar V_{m,2}}$ V ˉ m , 2 , excess partial molar volumes, $\bar V_{m,1}^E$ V ˉ m , 1 E and $\bar V_{m,2}^E$ V ˉ m , 2 E have been computed using the experimental observations. The partial molar volumes, $\bar V_{m,1}^o$ V ˉ m , 1 o and $\bar V_{m,2}^o$ V ˉ m , 2 o ; excess partial molar volumes, $\bar V_{m,1}^{oE}$ V ˉ m , 1 oE and $\bar V_{m,2}^{oE}$ V ˉ m , 2 oE at infinite dilution were also calculated. The variations of these parameters as a function of composition and temperature are discussed in terms of the intermolecular interactions in the studied binary mixtures. [ABSTRACT FROM AUTHOR]

Fish biologists have long assumed a link between intestinal length and diet, and relative gut length or Zihler's index are often used to classify species into trophic groups. This has been done for specific fish taxa or specific ecosystems, but not for a global fish dataset. Here, we assess these relationships across a dataset of 468 fish species (254 marine, 191 freshwater, and 23 that occupy both habitats) in relation to body mass and fish length. Herbivores had significantly relatively stouter bodies and longer intestines than omni- and faunivores. Among faunivores, corallivores had longer intestines than invertivores, with piscivores having the shortest. There were no detectable differences between herbivore groups, possibly due to insufficient understanding of herbivorous fish diets. We propose that reasons for long intestines in fish include (i) difficult-to-digest items that require a symbiotic microbiome, and (ii) the dilution of easily digestible compounds with indigestible material (e.g., sand, wood, exoskeleton). Intestinal indices differed significantly between dietary groups, but there was substantial group overlap. Counter-intuitively, in the largest dataset, marine species had significantly shorter intestines than freshwater fish. These results put fish together with mammals as vertebrate taxa with clear convergence in intestine length in association with trophic level, in contrast to reptiles and birds, even if the peculiar feeding ecology of herbivorous fish is probably more varied than that of mammalian herbivores. [ABSTRACT FROM AUTHOR]

Multi-channel dilution analysis (MCDA) is a new calibration method that performs multiple dilutions of a standard solution as it makes its way from an autosampler to an analytical instrument. MCDA is based on the standard dilution analysis (SDA) method that combines the traditional standard additions and internal standardization calibration methods, correcting for both matrix interferences and fluctuations in signal levels associated with variations in the sample environment. Analysts operate the instrument in the normal manner, as all dilutions are performed automatically by splitting the sample stream entering the instrument into multiple channels of different tubing diameters and lengths. This setup results in a signal "stairstep" as portions of solution are measured at different points in time. A calibration curve is prepared from the plateau regions of the signal stairstep. MCDA has been exhibited using inductively coupled plasma optical emission spectrometry, which is a workhorse for the determination of trace metals in solution. However, MCDA is applicable for any analyte of interest in any sample type, as long as the selected measurement technique accepts samples as a flowing liquid stream. MCDA is applied to the analysis of three certified reference materials by inductively coupled plasma optical emission spectrometry (ICP-OES). Percent recoveries for a suite of analytes range from 87--106%, with relative standard deviations on the order of 1%. MCDA simplifies the analysis process, increasing sample throughput by significantly decreasing the time required for solution preparation. [ABSTRACT FROM AUTHOR]

Since 2014, highly pathogenic avian influenza (HPAI) H5 viruses of clade 2.3.4.4 have been dominating the outbreaks across Europe, causing massive deaths among poultry and wild birds. However, the factors shaping these broad‐scale outbreak patterns, especially those related to waterbird community composition, remain unclear. In particular, we do not know whether these risk factors differ from those of other H5 clades. Addressing this knowledge gap is important for predicting and preventing future HPAI outbreaks. Using extensive waterbird survey datasets from about 6883 sites, we here explored the effect of waterbird community composition on HPAI H5Nx (clade 2.3.4.4) spatial patterns in the 2016/2017 and 2020/2021 epidemics in Europe, and compared it with the 2005/2006 HPAI H5N1 (clade 2.2) epidemic. We showed that HPAI H5 occurrences in wild birds in the three epidemics were strongly associated with very similar waterbird community attributes, which suggested that, in nature, similar interspecific transmission processes operate between the HPAI H5 subtypes or clades. Importantly, community phylogenetic diversity consistently showed a negative association with H5 occurrence in all three epidemics, suggesting a dilution effect of phylogenetic diversity. In contrast, waterbird community variables showed much weaker associations with HPAI H5Nx occurrence in poultry. Our results demonstrate that models based on previous epidemics can predict future HPAI H5 patterns in wild birds, implying that it is important to include waterbird community factors in future HPAI studies to predict outbreaks and improve surveillance activities. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pesticide dilution is one of the essential aspects of plant protection. However, the effect of dilution on the deposition characteristics of pesticide droplets containing particulate additives on crop leaf surfaces remains unclear and warrants further research. Herein, a validated computational fluid dynamics (CFD)‐volume of fluid (VOF)‐discrete phase model (DPM) numerical model was developed to analyze the influence of particle content on the deposition behavior of droplets on the leaf surface comparatively, taking into account the particle content of different diluted thifluzamide solutions. Additionally, the study aimed to analyze further the kinetic behavior of pesticide droplets landing on rice leaves across different dilution conditions. RESULTS: Pesticide droplets diluted 100‐fold had a lower retraction rate during spreading than particle‐free droplets, so the solution is more easily deposited in the leaves. Moreover, the low dilution (high concentration) increased the critical adhesion rate between droplets and rice leaves, inhibiting the bouncing of droplets on the leaf surface, thus promoting their effective deposition on the surface. In addition, low dilution (high concentration) is not conducive to spreading droplets when the impact velocity is high, and it also results in a large amount of pesticide use. CONCLUSION: The actual application process can be through understanding the dilution factor of the configured pesticide solution, and reasonable adjustment of the nozzle pressure can effectively improve the utilization rate of pesticides and reduce the pollution brought by pesticides to the environment. These results provide an essential reference for studying pesticide droplet deposition characteristics, including rice plant protection and spraying technology. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

AbstractLow carbon steels can be cladded with super-duplex stainless steels to enhance the surface’s mechanical and wear properties. The current study examines the impact of process parameters on weld bead geometry and dilution % during cold metal transfer (CMT) cladding of super duplex stainless steel 2507 over low carbon steel. Response Surface Methodology (RSM) with a Central Composite Design matrix was used to optimize the process parameters (welding current, welding speed, and nozzle to workpiece distance (NTD)). The adequacy of the model was checked using an ANOVA analysis. The optimal bead width, height, penetration, and dilution values were 8.05 mm, 4.52 mm, 1.56 mm and 14.64%, respectively. The ideal input parameters were 200 A of welding current, 4.64 mm/s of welding speed, and 14 mm of NTD. The welding speed is the most dominant parameter, followed by the welding current and NTD. The cladding samples were prepared from the optimal parameters. The CMT-clad layer’s microstructure, microhardness, and wear properties were also evaluated. The results indicate a dense crack-free and non-porous clad surface was obtained under optimal conditions. [ABSTRACT FROM AUTHOR]

In this study, the detonation behaviors of stoichiometric methane-hydrogen-oxygen (CH 4 –H 2 -2.5O 2) mixtures, diluted or not with carbon dioxide (CO 2), nitrogen (N 2) or helium (He), were investigated. By varying the initial pressure (p 0) or CO 2 , N 2 or He dilution concentration (0–60%), four modes of propagation could be clearly identified: stable detonation, fluctuation mode, galloping mode, and low-velocity mode. For each tested mixture, the detonation limit pressures for low-velocity mode were determined. It has been found that for given mixtures at higher dilutions, higher initial pressures are required to achieve steady mode with nitrogen dilution compared to helium dilution. As the initial pressure decreases and the dilution concentration increases, that will lead to the increase of the induction zone length and the more obvious influence of the pipeline boundary layer. This results in the increase of energy loss and velocity deficit during the propagation of detonation wave in the pipeline. As close to the critical limit pressures, there will be fluctuation, galloping and low-velocity detonation propagation modes. Depending on the type of the dilution gas as well as its concentration, the form of propagation mode at critical limit pressures will also be different. • The critical limit for different propagation modes for CH 4 –H 2 -2.5O 2 - diluted mixtures is analyzed. • Detonation velocity deficits for CH 4 –H 2 -2.5O 2 - diluted mixtures are determined. • The prediction formulas of CH 4 –H 2 -2.5O 2 - diluted mixtures between the induction zone length and initial pressure are performed. [ABSTRACT FROM AUTHOR]

The addition of hydrogen in a dual-fuel mode based on natural gas and diesel offers great potential for improving engine efficiency and reducing emissions. Therefore, detailed numerical simulations have been used to explore the effects of soot formation characteristics of natural gas-diesel dual-fuel engines doped by hydrogen at elevated pressure. Numerical simulations are compared with available experimental data, the effects of H 2 addition on soot formation in laminar CH 4 + n-heptane, H 2 + CH 4 + n-heptane, FH 2 + CH 4 + n-heptane diffusion flames at 2, 4, 6 and 8 atm are simulated, FH 2 is added to separate the H 2 chemical effects. The results show that the dilution and thermal effects of H 2 inhibit soot formation, while the chemical effects of H 2 promote soot formation under different pressures. The addition of H 2 increases the concentration of H and OH radicals, which promotes the formation of C 2 H 2 and benzene (A1). By simplifying the reaction path and analyzing the production rate of A1, the mechanism of H 2 addition to promote A1 formation is illustrated. The concentrations of polycyclic aromatic hydrocarbon (PAH) pyrene (A4), benzo(ghi)fluoranthene (BGHIF) and benzo(a)pyrene (BAPYR) are inhibited at higher pressures that result in lower inception and condensation rates. Therefore, the increase of hydrogen abstraction acetylene addition (HACA) rate is the main reason for the increase of soot formation under chemical effects. While the O 2 oxidation rate decreases and the OH oxidation rate increases, that is due to the decrease of O 2 concentration and the increase of OH concentration in the soot formation area under chemical effects. • The dilution, thermal and chemical effects of H 2 addition on soot formation in methane/n-heptane flame were investigated at high pressures. • Key specie A1 formation pathways and related reactions were confirmed when H 2 addition. • The changes of soot formation and oxidation mechanisms with H 2 addition in different pressure were explained. [ABSTRACT FROM AUTHOR]

Detecting life has driven research and exploration for centuries, but recent attempts to compile and generate a framework that summarizes life features, aimed to develop strategies for life detection missions beyond planet Earth, have disregarded a key life feature: behavior. Yet, some behaviors such as biomineralization or motility have occasionally been proposed as biosignatures to detect life. Here, we capitalize on a specific taxis' motility behavior, magnetotaxis, to experimentally provide insights in support of behavior as an unambiguous, sensitive biosignature, and magnetic forces as a prescreening option. Using a magnetotactic bacterial species, Magnetospirillum magneticum, we conducted a lab sensitivity experiment comparing PCR with the hanging drop behavioral assay, using a dilution series. The hanging drop behavioral assay visually shows the motility of MTB toward magnetic poles. Our findings reveal that the behavioral assay exhibits higher sensitivity in the detection of M. magneticum when compared to the established PCR protocol. While both methods present similar detection sensitivities at high concentrations, at ≥ 10–7 fold dilutions, the behavioral method proved more sensitive. The behavioral method can detect bacteria even when samples are diluted at 10–9. Comparable results were obtained with environmental samples from the Hula Valley. We propose behavioral cues as valuable biosignatures in the ongoing efforts of life detection in unexplored aquatic habitats on Earth and to stimulate and support discussions about how to detect extant life beyond Earth. Generic and robust behavioral assays can represent a methodological revolution. [ABSTRACT FROM AUTHOR]

The NO-reburning by C 3 H 8 /H 2 mixtures with N 2 and CO 2 dilutions is systematically studied using a jet-stirred reactor. Experimental and kinetic studies are performed to assess the impacts of temperature (T), equivalence ratio (Φ), H 2 proportion in fuel, initial NO volume fraction (X NO), and CO 2 volume fraction (X CO2). NO-reburning and HCN formation are inhibited with CO 2 dilution. The inhibition of CO 2 on NO-reburning diminishes at T > 1200 K and Φ > 1.5. The NO reduction efficiency peaks at T = 1200–1300 K when Φ ≥ 1. At Φ = 2.2 and T = 1300 K, NO reduction amounts to 71.7% with CO 2 dilution. With X H2 /(X H2 + X C3H8) ≤ 0.5, the inhibition of H 2 on NO-reburning with CO 2 dilution is weak. The recommended reaction condition is identified to reduce both NO and CO 2 emissions. This research provides new insights into NO-reburning using C 3 H 8 /H 2 mixtures with N 2 and CO 2 dilutions. • At T = 1300 K and Φ = 2.2, 71.7% NO is reduced when diluted with CO 2. • 50% H 2 addition reduces carbon emissions and keeps high NO reduction efficiency. • The CO 2 dilution inhibits HCN generation and NO reduction. • The optimal Φ for NO-reburning with CO 2 dilution increases with T. [ABSTRACT FROM AUTHOR]

During the preparation of high dilutions, repeated external vibration (shaking) is used. We hypothesized that it was the vibration treatment, and not the negligible content of the initial substance, that underlies the activity of highly diluted preparations. In order to test this, the vibration was separated from the dilution process. After vibrating two tubes together on a vortex mixer (one containing water and the other the initial substance) the electrical conductivity and radio frequency radiation intensity of water differed from the unvibrated control, and the ability to exert a modifying effect on the target solution appeared, as assessed using ELISA and terahertz spectroscopy, appeared. Thus, the properties of the neutral carrier (water) changed after non-contact exposure to the initial substance. We have named this process 'crossing' and its products 'aqueous iterations of the initial substance'. Several aqueous iterations with different physical properties were obtained, some of which have a modifying effect and others cause various chemical (catalytic) and biological (antiviral) effects similar to those of the initial substance. This indicates that during crossing, substances enter into post-vibration supramolecular interactions. At the nanoscale level, aqueous iterations and the initial substance are structurally symmetrical, which allows us to assume that the preservation of the symmetry of substances subjected to vibration treatment is the basis of the post-vibration interaction phenomenon. [ABSTRACT FROM AUTHOR]

Objective: Arterial-phase artifacts are gadoxetic acid (GA)–enhanced MRI's major drawback, ranging from 5 to 39%. We evaluate the effect of dilution and slow injection of GA using automated fluoroscopic triggering on liver MRI arterial-phase (AP) acquisition timing, artifact frequency, and lesion visibility. Methods and materials: Saline-diluted 1:1 GA was injected at 1 ml/s into 1413 patients for 3 T liver MRI. Initially, one senior abdominal radiologist, i.e., principal investigator (PI), assessed all MR exams and compared them to previous and follow-up images, as well as the radiology report on record, determining the standard of reference for lesion detection and characterization. Then, three other readers independently evaluated the AP images for artifact type (truncation (TA), transient severe motion (TSM) or mixed), artifact severity (on a 5-point scale), acquisition timing (on a 4-point scale) and visibility (on a 5-point scale) of hypervascular lesions ≥ 5 mm, selected by the PI. Artifact score ≥ 4 and artifact score ≤ 3 were considered significant and non-significant artifacts, respectively. Results: Of the 1413 exams, diagnostic-quality arterial-phase images included 1100 (77.8%) without artifacts, 220 (15.6%) with minimal, and 77 (5.4%) with moderate artifacts. Only 16 exams (1.1%) had significant artifacts, 13 (0.9%) with severe artifacts (score 4), and three (0.2%) non-diagnostic artifacts (score 5). AP acquisition timing was optimal in 1369 (96.8%) exams. Of the 449 AP hypervascular lesions, 432 (96.2%) were detected. Conclusion: Combined dilution and slow injection of GA with MR results in well-timed arterial-phase images in 96.8% and a reduction of exams with significant artifacts to 1.1%. Clinical relevance statement: Hypervascular lesions, in particular HCC detection, hinge on arterial-phase hyperenhancement, making well-timed, artifact-free arterial-phase images a prerequisite for accurate diagnosis. Saline dilution 1:1, slow injection (1 ml/s), and automated bolus triggering reduce artifacts and optimize acquisition timing. Key Points: • There was substantial agreement among the three readers regarding the presence and type of arterial-phase (AP) artifacts, acquisition timing, and lesion visibility. • Impaired AP hypervascular lesion visibility occurred in 17 (3.8%) cases; in eight lesions due to mistiming and in nine lesions due to significant artifacts. • When AP timing was suboptimal, it was too late in 40 exams (3%) and too early in 4 exams (0.2%) of exams. [ABSTRACT FROM AUTHOR]

This paper evaluates 16 year results of the Allergy EQA program shared by EQA organisers in Belgium, Finland, Portugal, and The Netherlands. The performance of Thermo Fisher and Siemens user groups (in terms of concordance between both groups, between laboratory CV, prevalence of clinically significant errors) and suitability of samples (stability and validity of dilution of patient samples) are evaluated using data of 192 samples in the EQA programs from 2007 to 2022. Measurands covered are total IgE, screens and mixes, specific IgE extracts and allergen components. There is perfect (53 %), acceptable (40 %) and poor (6 %) concordance between both method groups. In case of poor concordance the best fit with clinical data is seen for Thermo Fisher (56 %) and Siemens (26 %) respectively. The between laboratory CV evolves from 7.8 to 6.6 % (Thermo Fisher) and 7.3 to 7.7 % (Siemens). The prevalence of blunders by individual laboratories is stable for Siemens (0.4 %) and drops from 0.4 to 0.2 % for Thermo Fisher users. For IgE, the between year CV of the mean of both user groups is 1 %, and a fifteen-fold dilution of a patient sample has an impact of 2 and 4 % on the recovery of Thermo Fisher and Siemens user groups. The analytical performance of Thermo Fisher is slightly better than that of Siemens users but the clinical impact of this difference is limited. Stability of the sample and the low impact of dilution on the recovery of measurands demonstrates the suitability for purpose of the EQA program. [ABSTRACT FROM AUTHOR]

The cooling capacity of a typical dilution refrigerator is mainly determined by the circulating flow of the He-3 in the system, which is usually realized by the external circulation pump. In order to increase the concentration of circulating He-3, the still often take the orifice structure to limit the influence of the superfluid helium film, and this structure will also have a certain impact on the flow rate of He-3. This paper summarizes the flow rate models of each part of the orifice structure, and establishes a model related to the influence of pumping speed and the diameter of orifice on the flow rate of circulating He-3. The relationship between pumping speed and flow rate is developed and the relation is divided into three phases for detailed analysis. It is found that the flow rate and the concentration of circulating He-3 increase first and then decrease with the increasing diameter of orifice at a certain pumping speed, and the possible reasons for this phenomenon are analyzed. The results indicate that there is an optimal orifice diameter at a determined pumping speed. [ABSTRACT FROM AUTHOR]

Dissimilar welds between ferritic and austenitic stainless steels are widely used in industrial applications. Taking into account the issues inherent to arc welding, such as the high heat input and the need to carry out multiple passes in the case of thick plates, a procedure with two simultaneous laser beams (working in a single pass) and consumable inserts as filler metal has been considered. Particular attention was paid to the choice of the filler metal (composition and amount), as well as welding parameters, which are crucial to obtain the right dilution necessary for a correct chemical composition in the weld zone. The first experimental investigations confirmed the achievement of a good weldability of the dissimilar pair ASTM A387 ferritic/AISI 304L austenitic steel, having ascertained that the microstructure of the weld zone is austenitic with a little amount of residual primary ferrite, which is the best condition to minimize the risk of hot cracking. [ABSTRACT FROM AUTHOR]

We investigate the zero-temperature hysteresis characteristics of the diluted random field 3-state clock model under a cyclic driving field with zero frequency. This analysis is conducted in the presence of two types of quenched random fields within the mean field approximation. The influence of dilution on the hysteretic response of the model at moderate concentration levels is observed to be contingent on the particular form of disorder. Following this, simulations on a simple cubic lattice are performed for a comparative analysis with mean field predictions. [ABSTRACT FROM AUTHOR]

Background: This study aimed to compare the lipemia removal efficiency of highspeed centrifugation, lipid scavengers, and dilution for biochemical analytes. Methods: We collected 30 cases of lipemic plasma in an emergency laboratory and divided them into 4 aliquots. Lipemia was removed by highspeed centrifugation, lipid scavenger, dilution, and ultracentrifugation, then analytes were measured by an AU5800 analyzer. Taking ultracentrifugation as reference, the efficiencies of the other three methods were evaluated based on the deviation. Results: When highspeed centrifugation was used for lipemia removal, DBIL (18.62%), and Magnesium (6.09%) could not satisfy the criterion. When lipid scavengers were applied to remove lipemia, CRP (-86.70%), TP (-8.29%), CKMB (-44.85%), DBIL (37.96%), Glu (4.20%) and phosphate (14.32%) were not suggested as lipid scavengers. For dilution, nearly half of the analytes could satisfy the criterion, including AMY (2.41%), CRP (5.54%), ALT (2.85%), GGTL (-1.73%), ALP (-0.04%), Glu (-0.84%), LDH (0.06%), CK (0.68%), BUN (3.80%), CREA (-1.54%), UA (5.42%), and magnesium (0.43%). Conclusions: Neither of the methods for lipid removal could satisfy all emergency department tests for lipid removal. This finding suggests that removing lipemia in the clinical laboratory should be based on the characteristics and the method of testing. [ABSTRACT FROM AUTHOR]

This paper deals with a model of chemostat with two cross‐feeding species and involving two inhibitions. The excess of hydrogen inhibits the growth of acetogenic bacteria which, in turn, inhibit the growth of methanogenic hydrogenotrophic bacteria. The model is described by a system of four ordinary differential equations. We established the conditions of existence and stability of equilibria with respect to the operating parameters which are the dilution rate and the input substrate concentrations of the species of the model, then we illustrate the operating and bifurcation diagrams. This technique makes it easy to interpret different regions of operating diagrams. Inhibitions let some regions of stability rise and others vanish. [ABSTRACT FROM AUTHOR]

The transition from hydrocarbon-based to carbon-free fuels is imperative owing to environmental concerns and stricter regulations. However, the combustion of hydrogen (H 2) and ammonia (NH 3) generates nitrogen oxide (NO) and faces operational constraints. Hence, technologies like flameless and moderate or intense low-oxygen dilution combustion are being explored to mitigate NO formation. This study analyzed flameless combustion of H 2 /NH 3 /N 2 fuel mixture, assessing the impacts of varying fuel velocity, feed strategy, equivalence ratio, and O 2 content on NO emissions. Using a laboratory-scale combustor, flameless combustion was achieved via controlled flow and internal recirculation. Lower fuel velocity improved combustor temperature uniformity and reduced NO emissions. Feeding NH 3 separately decreased NO emissions compared to mixing it with fuel. Decreasing excess O 2 enhanced temperature uniformity, suppressed fuel-NO formation, and reduced NO emissions. N 2 dilution improved fuel-oxidizer mixing, enhancing temperature uniformity and reducing NO emissions, highlighting how parameter optimization enhances temperature uniformity and lowers NO emissions. • We investigated H 2 /NH 3 /N 2 flameless combustion characteristics and NO emissions. • Decreasing the fuel velocity decreased NO emissions. • Feeding ammonia separately decreased NO emissions. • An increased equivalence ratio decreased NO emissions. • A reduced O 2 content in the oxidizer decreased NO emissions. [ABSTRACT FROM AUTHOR]

This study addresses the effect of using animal excreta on the nutritional content of forages, focusing on macro- and micro-element concentrations (nitrogen; N, phosphorus; P, sulphur; S, copper; Cu, zinc; Zn, manganese; Mn, selenium; Se) from animal feed to excreta, soil, and plants. Data were collected from pot and field trials using separate applications of sheep or cattle urine and faeces. Key findings indicate that soil organic carbon (SOC) and the type of excreta significantly influences nutrient uptake by forages, with varied responses among the seven elements defined above. Although urine contributes fewer micronutrients compared to faeces (as applied at a natural volume/mass basis, respectively), it notably improves forage yield and micronutrient accumulation, thus potentially delivering positive consequences at the farm level regarding economic performance and soil fertility when swards upon clayey soil types receive said urine in temperate agro-climatic regions (i.e., South West England in the current context). In contrast, faeces application in isolation hinders Se and Mn uptake, once again potentially delivering unintended consequences such as micronutrient deficiencies in areas of high faeces deposition. As it is unlikely that (b)ovine grazing fields will receive either urine or faeces in isolation, we also explored combined applications of both excreta types which demonstrates synergistic effects on N, Cu, and Zn uptake, with either synergistic or dilution effects being observed for P and S, depending largely on SOC levels. Additionally, interactions between excreta types can result in dilution or antagonistic effects on Mn and Se uptake. Notably, high SOC combined with faeces reduces Mn and Se in forages, raising concerns for grazed ruminant systems under certain biotic situations, e.g., due to insufficient soil Se levels typically observed in UK pastures for livestock growth. These findings underscore the importance of considering SOC and excreta nutritional composition when designing forage management to optimize nutrient uptake. It should be noted that these findings have potential ramifications for broader studies of sustainable agriculture through system-scale analyses, as the granularity of results reported herein elucidate gaps in knowledge which could affect, both positively and negatively, the interpretation of model-based environmental impact assessments of cattle and sheep production (e.g., in the case of increased yields [beneficial] or the requirement of additional synthetic supplementation [detrimental]). [ABSTRACT FROM AUTHOR]

For population systems modeled by age‐structured hyperbolic partial differential equations (PDEs), we redesign the existing feedback laws, designed under the assumption that the dilution input is directly actuated, to the more realistic case where dilution is governed by actuation dynamics (modeled simply by an integrator). In addition to the standard constraint that the population density must remain positive, the dilution dynamics introduce constraints of not only positivity of dilution, but possibly of given positive lower and upper bounds on dilution. We present several designs, of varying complexity, and with various measurement requirements, which not only ensure global asymptotic (and local exponential) stabilization of a desired positive population density profile from all positive initial conditions, but do so without violating the constraints on the dilution state. To develop the results, we exploit the relation between first‐order hyperbolic PDEs and an equivalent representation in which a scalar input‐driven mode is decoupled from input‐free infinite‐dimensional internal dynamics represented by an integral delay system. [ABSTRACT FROM AUTHOR]

This study examines the potential impacts of projected atmospheric carbon dioxide (pCO2) levels reaching 800 ppm by the end of the century, focusing on ocean acidification effects onmarine ecosystems in the coastal areas of Bohai.We investigated how acidification affects the grazing patterns of microzooplankton using dilution techniques and ecophysiological methods. Our findings indicate that acidic conditions shift the phytoplankton community structure, changing dominant species. Elevated CO2 concentrations reduced grazing pressure on phytoplankton, with less steep declines in growth rates at 800 ppm CO² (spring: 2.43 d-1 vs. 2.16 d-1, summer: -0.46 d-1 vs. -0.73 d-1, autumn: -0.45 d-1 vs. -0.90 d-1) and significant decreases in grazing pressure percentages (%Pp from 0.84 to 0.58 and %Pi from 0.64 to 0.46). Short-term acid exposure significantly increased superoxide dismutase activity in both microplankton (from 0.03 to 0.08 U mg-1, p<0.01) and nanoplankton (from 0.05 to 0.09 U mg-1, p<0.001), indicating an adaptive response to oxidative stress. These results highlight that elevated CO2 levels primarily boost phytoplankton growth by reducing microzooplankton grazing pressure, resulting in higher growth rates and a shift towards smallersized phytoplankton, reflecting complex short-term ecological responses to acidification. Further research is needed to understand the long-term effects of ocean acidification on microzooplankton and their role in marine secondary productivity. [ABSTRACT FROM AUTHOR]

To reveal the deflagration hazard and propagation law of hydrogen-enriched natural gas (H 2 NG) in closed spaces, this paper studied the deflagration characteristic parameters under different H 2 blended ratio (λ) and inert gas dilution fraction (X dilution) in slender closed pipelines with steel circular hole obstacles. The results indicate that the positive feedback mechanism's sustained effect, failure, and re-action leads to a "three-zone" distribution of H 2 NG explosion overpressure along the pipeline, namely the acceleration, attenuation, and rebound zones. The maximum explosion overpressure (P max), maximum pressure rise rate ((dP/dt) max), and peak shock wave propagation velocity (V p) all increase with the increase of λ. The rise of λ has the most significant enhancement effect on (dP/dt) max , while the enhancement effect on V p is the smallest. This is because the main reasons affecting their increase are different. P max , (dP/dt) max , and V p exhibit exponential decay with increased N 2 and CO 2. However, CO 2 has a more significant inhibitory effect on the H 2 NG deflagration process. When X CO2 = 25% and X CO2 = 30%, the deflagration process of H 2 NG with λ = 20% and λ = 80% can be inhibited entirely, respectively, which has important guiding significance for the safe application of H 2 NG. • The evolution law of deflagration shock waves in slender closed pipelines by H 2 NG was researched. • Effects of H 2 blended ratio and N 2 /CO 2 dilution fraction on H 2 NG deflagration characteristics were revealed. • The effects of N 2 /CO 2 dilution fraction on the P max , (dP/dt) max , and V p were predicted by an exponential model. [ABSTRACT FROM AUTHOR]

Plasma-assisted reforming shows great promise for making ammonia compatible with current engine technology, with minimal modifications required. This study examines the impact of various discharge, flow, and composition parameters on ammonia conversion into hydrogen using a new well-stirred homogeneous plasma reactor. Gas chromatography was used to measure hydrogen and oxygen, while ICCD imaging evaluated plasma homogeneity. Initial mixture composition significantly influences the response to plasma conditions. Relative to the initial ammonia composition, the conversion of pure ammonia yields a lower hydrogen percentage when compared to air-diluted mixtures. Introducing air changes the relationship between pulsed energy deposition and hydrogen production, resulting in a more substantial increase in conversion. Efficiency calculations demonstrate that high ammonia content and high pulse frequencies improve yields, while longer residence times in the reactor result in higher temperatures, also increasing yields. These findings provide insights into the underlying mechanisms of ammonia cracking and reforming in a discharge, and will serve to promote further investigation into plasma reforming strategies. • Enhanced hydrogen production from plasma-assisted reforming of ammonia influenced by initial mixture composition. • Optimal hydrogen yields achieved with high ammonia content and high pulse repetition frequency of plasma discharges. • Effective reforming strategies demonstrated for longer residence times in reactor due to gas heating. [ABSTRACT FROM AUTHOR]

The phage lysin field has done nothing but grow in the last decades. As a result, many different research groups around the world are contributing to the field, often with certain methodological differences that pose a challenge to the interpretation and comparison of results. In this work, we present the case study of three Acinetobacter baumannii‐targeting phage lysins (wild‐type endolysin LysMK34 plus engineered lysins eLysMK34 and 1D10) plus one lysin with broad activity against Gram‐positive bacteria (PlySs2) to provide exemplary evidence on the risks of generalization when using one of the most common lysin evaluation assays: the killing assay with resting cells. To that end, we performed killing assays with the aforementioned lysins using hypo‐, iso‐ and hypertonic buffers plus human serum either as the reaction or the dilution medium in a systematic manner. Our findings stress the perils of creating hypotonic conditions or a hypotonic shock during a killing assay, suggesting that hypotonic buffers should be avoided as a test environment or as diluents before plating to avoid overestimation of the killing effect in the assayed conditions. As a conclusion, we suggest that the nature of both the incubation and the dilution buffers should be always clearly identified when reporting killing activity data, and that for experimental consistency the same incubation buffer should be used as a diluent for posterior serial dilution and plating unless explicitly required by the experimental design. In addition, the most appropriate buffer mimicking the final application must be chosen to obtain relevant results. [ABSTRACT FROM AUTHOR]

Objectives: This research aimed to replicate the Swinson, D., Snaith, J., Buckberry, J., & Brickley, M. (2010). High performance liquid chromatography (HPLC) in the investigation of gout in paleopathology. International Journal of Osteoarchaeology, 20, 135–143. https://doi.org/10.1002/oa.1009 method for detecting uric acid in archeological human remains to investigate gout in past populations and to improve the original High Performance Liquid Chromatography‐ultraviolet (HPLC‐UV) method by using HPLC‐mass spectrometry (HPLC‐MS), a more sensitive, compound‐specific detection method. Materials and Methods: We used reference samples of uric acid to create a dilution series to assess the limits of quantification and detection. Samples from individuals with and without gout lesions were taken from foot bones and ribs from the English cemeteries of Tanyard, Hickleton, Gloucester, and Lincoln. Results: We could not replicate the results of Swinson and colleagues using HPLC‐UV. Tests using a dilution series of uric acid showed HPLC‐MS was approximately 100× more sensitive than HPLC‐UV, with the additional benefit of being compound specific. A newly developed hydrophilic interaction chromatography (HILIC) method improved retention characteristics. Fourteen samples from eight individuals, five with skeletal lesions consistent with gout, were analyzed with the final method. None showed evidence of uric acid despite the newly developed method's improved sensitivity and specificity. Discussion: The lack of detectable uric acid extracted from these samples suggests that (1) urate crystals were not present in any of the bone samples, regardless of gout status; (2) urate crystals did not survive these specific archeological conditions; or (3) the concentration of uric acid in our bone extracts was low, and thus larger samples would be required. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate how weld overlays with nickel superalloys are important for the integrity, due the high temperatures and corrosive environments that can be experienced in mineral processing environments, of mining and processing equipment. The Ni-Cr-Mo superalloy Inconel 686 overlays are fabricated through automatic gas metal arc welding with variations in arc voltage and travel speed (i.e., heat input), and they have overlap between adjacent weld tracks for applications in the mining and minerals sector. The impact of variations in the process parameters and the size of the weld overlapping on the dilution, solidification morphology, microsegregation, and microhardness were investigated. Both geometric and chemical composition definitions were used to quantify the extent of the weld dilution. Subsequently, the weld geometry and dilution were correlated with the solidification microstructure and phase transformations. The maximum dilutions were measured to be 13.63% (1/2 overlap, 5.96 kJ·cm−1) and 15.39% (1/3 overlap, 4.77 kJ·cm−1), which shows that less of an overlap increases the dilution level. Scanning electron microscopy and chemical composition analysis revealed that an increase in weld heat input and dilution level led to higher levels of microsegregation for Mo and Cr, as well as the volume fraction of Mo- and Cr-rich phases in the interdendritic/intercellular regions in the overlay layer. Analysis of the weld overlays in the current study revealed strong and unprecedented connections between the weld overlay process conditions, the resultant metallurgy (i.e., dendrite arm spacing, microsegregation, and phase formation), and the hardness of the overlay. It was concluded that the optimal weld overlays in the processing window studied in this investigation were fabricated at mid-level heat inputs (i.e., 4–5 kJ·cm−1) and a 1/2 track overlap. [ABSTRACT FROM AUTHOR]

In this study, the effect of limestone content on the mechanical performance and the heat of hydration of ordinary Portland cement (OPC) was investigated. Changes in the phase assemblage were analyzed through XRD and thermodynamic modeling. The purpose of the study was to identify the optimal limestone content in OPC. As a result of the experiment, all samples were found to have equal fluidity. Increasing the limestone content accelerated the hydration of the cement before approximately 13 h and shortened the setting time due to the acceleration of the initial hydration reaction. The compressive strength of the cement mortar showed a dilution effect, with lower compressive strength compared to the reference sample at an early age, but it gradually recovered at a later age. This is because, as shown in the XRD and thermodynamic modeling results, the carboaluminate phases formed due to the chemical effect of limestone contributed to the development of compressive strength. As a result, within the scope of this study, it is believed that maintaining the limestone content in OPC within 10% is optimal to minimize quality degradation. [ABSTRACT FROM AUTHOR]

This research investigated the effect of kitchen wastewater (KWW) concentrations and pretreatment methods on Chlorella vulgaris biomass production, lipid content and nutrient removal. This study was divided into two separate experiments. The first experiment determined the appropriate dilution rate of KWW for the growth of microalgae, sterilized KWW was varied between 25%, 50%, 75%, and 100%(v/v). The result indicated that 50%(v/v) showed the highest nutrient removal by 90.23%, 85.87%, and 80.64% of sCOD, TKN, and TP, respectively. The highest biomass and lipid content were obtained with 50%(v/v) (1.447 g/L, 37.9%). The second experiment was to find an effective physical pretreatment method, which separated the biotic contaminant, non-sterilized KWW was diluted 50%(v/v) and filtered with different mesh size filters (150 μm, 50 μm, and 30 μm) compared with sterilized KWW as a control sample. The result indicated that pretreatment with 50 μm filtration was found highest nutrient removal by 90.51%, 84.74%, and 77.50% of sCOD, TKN, and TP, respectively. The highest biomass and lipid content were obtained with 50 μm filtration (1.496 g/L, 39.4%). Our results support the hypothesis that the optimal dilution and proper filtration of KWW helps create more favorable environment for microalgal growth. The application of microalgae in actual wastewater treatment was the improper amount of nutrients and the presence of biotic contaminant in the non-sterilized wastewater, which is inhibit the microalgae growth. Hence, it is necessary to develop the technique for controlling biotic contamination and appropriately diluting wastewater to enable full-scale microalgae cultivation in the future. [ABSTRACT FROM AUTHOR]

We have successfully developed cryogen-free dilution refrigerators with medium cooling power that can be applied to quantum experiments. Breakthroughs have been made in some key technologies and components of heat switches and dilution units. Our prototype has been running continuously and stably for more than 100 hours below 10 mK, with a minimum temperature of 7.6 mK and a cooling power of 450 μW at 100 mK. At the same time, we have also made progress in the application of dilution refrigerators, such as quantum computing, low-temperature detector, and magnet integration. These indicators and test results indicate good prospects for application in physics, astronomy, and quantum information. [ABSTRACT FROM AUTHOR]

The need for elemental analysis in quality control of food, pharmaceuticals and cosmetics, taking into account human safety, has become an essential requirement for any product destinated for commercialization and targets in particular potentially toxic elements. The main objective is to obtain reliable data on elemental content that enables end-users to make informed decisions and to address problems effectively. To align with the principles of green and sustainable analytical chemistry, recent efforts have focused on incorporating new, low-cost screening and quantitative analytical tools such as total reflection X-ray fluorescence spectrometry (TXRF). This paper provides an overview of recent TXRF applications in the elemental analysis of food, pharmaceuticals, and cosmetic samples. The state-of-the-art procedures for sample preparation with details on the sample type and amount, dilution steps, mixing agents, analysed elements, and addition of internal calibration standards are presented together with analytical parameters such as limits of detection and quantification. The current challenges for applying TXRF to each of these research fields are discussed. [ABSTRACT FROM AUTHOR]

This study investigated how structural parameters (including injection ducts and exhaust nozzle inner diameters) affect the internal flow field and dilution ratio of diesel particulate sampling diluters. Increasing air injection duct diameter increased the injection chamber pressure and decreased the air velocity peak, mixed gas flow velocity, sample temperature, and mixing rate. Excessively small tube diameters caused uneven and discontinuous flow field distributions, while substantial air blockage rendered the flow state poor. Increasing nozzle inner diameters increased the exhaust flow area and the sample temperature, but decreased the velocity of the exhaust and gas mixtures and the pressure drop. Compared with a 2.0 mm inner diameter, 2.5 and 3.0 mm diameters decreased the peak velocity by 11.18% and 14.41%, respectively, and mixing slowed significantly. Inner nozzle diameters of <1.5 mm increased the pressure drop significantly; the exhaust velocity also increased, exceeding the air velocity at the mixing position. The dilution ratio and relative error decreased with increasing inner nozzle diameter. At an air injection duct and an inner nozzle diameter of 0.1 and 2.0 mm, respectively, the dilutor's flow field distribution improved, the mixed gas flow stabilized, and the dilution ratio and relative error were 21.34% and 6.74%, respectively. [ABSTRACT FROM AUTHOR]

The aim of this paper is to show that Tilman’s graphical method for the study of competition between two species for two resources can be advantageously used for the study of commensalism or syntrophy models, where a first species produces the substrate necessary for the growth of the second species. The growth functions of the species considered are general and include both inhibition by the other substrate and inhibition by the species’ limiting substrate, when it is at a high concentration. Because of their importance in microbial ecology, models of commensalism and syntrophy, with or without self-inhibition, have been the subject of numerous studies in the literature. We obtain a unified presentation of a large number of these results from the literature. The mathematical model considered is a differential system in four dimensions. We give a new result of local stability of the positive equilibrium, which has only been obtained in the literature in the case where the removal rates of the species are identical to the dilution rate and the study of stability can be reduced to that of a system in two dimensions. We describe the operating diagram of the system: this is the bifurcation diagram which gives the asymptotic behavior of the system when the operating parameters are varied, i.e., the dilution rate and the substrate inlet concentrations. [ABSTRACT FROM AUTHOR]

Copyright of GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This letter to the editor published in the Annals of Laboratory Medicine discusses the detection of a high-dose hook effect and the evaluation of dilutions of urine myoglobin specimens using a serum myoglobin assay. The authors explain that commercially available kits for measuring myoglobin levels are designed for serum or plasma, but severe muscle injuries can lead to myoglobin being released into the urine. The authors conducted experiments to determine the appropriate dilution factor for urine specimens to avoid the hook effect while still obtaining accurate results. They found that a 1:400 dilution was necessary for some specimens to obtain accurate results. The article recommends using a predilution step when analyzing urine specimens using the Roche Myoglobin assay. [Extracted from the article]

Abstract This study addresses the effect of using animal excreta on the nutritional content of forages, focusing on macro- and micro-element concentrations (nitrogen; N, phosphorus; P, sulphur; S, copper; Cu, zinc; Zn, manganese; Mn, selenium; Se) from animal feed to excreta, soil, and plants. Data were collected from pot and field trials using separate applications of sheep or cattle urine and faeces. Key findings indicate that soil organic carbon (SOC) and the type of excreta significantly influences nutrient uptake by forages, with varied responses among the seven elements defined above. Although urine contributes fewer micronutrients compared to faeces (as applied at a natural volume/mass basis, respectively), it notably improves forage yield and micronutrient accumulation, thus potentially delivering positive consequences at the farm level regarding economic performance and soil fertility when swards upon clayey soil types receive said urine in temperate agro-climatic regions (i.e., South West England in the current context). In contrast, faeces application in isolation hinders Se and Mn uptake, once again potentially delivering unintended consequences such as micronutrient deficiencies in areas of high faeces deposition. As it is unlikely that (b)ovine grazing fields will receive either urine or faeces in isolation, we also explored combined applications of both excreta types which demonstrates synergistic effects on N, Cu, and Zn uptake, with either synergistic or dilution effects being observed for P and S, depending largely on SOC levels. Additionally, interactions between excreta types can result in dilution or antagonistic effects on Mn and Se uptake. Notably, high SOC combined with faeces reduces Mn and Se in forages, raising concerns for grazed ruminant systems under certain biotic situations, e.g., due to insufficient soil Se levels typically observed in UK pastures for livestock growth. These findings underscore the importance of considering SOC and excreta nutritional composition when designing forage management to optimize nutrient uptake. It should be noted that these findings have potential ramifications for broader studies of sustainable agriculture through system-scale analyses, as the granularity of results reported herein elucidate gaps in knowledge which could affect, both positively and negatively, the interpretation of model-based environmental impact assessments of cattle and sheep production (e.g., in the case of increased yields [beneficial] or the requirement of additional synthetic supplementation [detrimental]).

The use of shielded metal arc welding (SMAW) equipment to synthesize alloys is one of the most promising methods as it can be used for in-situ fabrication. The hardness and corrosion properties of the deposited layer during the welding process can be enhanced by dilution of nichrome (NiCr) during the process. Therefore, the alloy was synthesized on the surface of the mild steel using SMAW equipment with various NiCr additions. The properties of the alloy were investigated using an X-ray diffraction (XRD), an Optical microscope, a Potentiostat, and a Vickers hardness apparatus. The appearance of martensite overlaps with the ferrite phase could be affected by the addition of NiCr to the alloy. An increase in NiCr content is followed by an increase in the lattice parameter value of the ferrite phase. The presence of a certain amount of nickel (Ni) contributes to the formation of lower transformation phases, including martensite. At the same time, the incorporation of chromium (Cr) also plays a significant role in promoting the formation of acicular ferrite. An increase in NiCr content in NiCr2 and NiCr3 samples results in a quantitative increase in martensite formation. Adding 0.434 g of NiCr to the weld deposited layer could result in the corrosion rate of the alloy being 0.1118 mm/y. Higher hardness is found in the NiCr3 sample, around 742.06 HV.

In plasma transferred arc welding (PTAW), the weld pool temperature often fluctuates. The spray weld layer is prone to overheating, leading to adverse effect on its performance. This study investigated the influence of spray welding current on the weld pool temperature and in turn on the microstructure, microhardness and corrosion resistance of the PTAW-Ni layer on a steel substrate. Weld pool temperature increased with increasing spray welding current and varied along the welding gun path before reaching the steady state. With increasing pool temperature, more Fe diffused from the substrate into the spray weld layer, leading to a widened fusion zone, an increased dilution rate and a decreased microhardness. The spray weld layer has a dendritic microstructure. The dendrites have a higher Cr content, while the interdendritic regions have a higher Ni content. Increasing weld pool temperature increased diffusion, resulting in reduced enrichment of the Cr and Ni elements. The increase of Fe and decrease of Cr in the spray weld layer caused the decreasing corrosion resistance.

B6O7OH62− is a highly polymerized borate anion of three six‐membered rings. Limited research on the B6O7OH62− hydrolysis mechanism under neutral solution conditions exists. Calculations based on density functional theory show that B6O7OH62− undergoes five steps of hydrolysis to form H3BO3 and BOH4−. At the same time, there are a small number of borate ions with different degrees of polymerization during the hydrolysis process, such as triborate, tetraborate, and pentaborate anions. The structure of the borate anion and the coordination environment of the bridging oxygen atoms control the hydrolysis process. Finally, this work explains that in existing experimental studies, the reason for the low B6O7OH62− content in solution environments with low total boron concentrations is that it depolymerizes into other types of borate ions and clarifies the borate species. The conversion relationship provides a basis for identifying the possibility of various borate ions existing in the solution. This work also provides a certain degree of theoretical support for the cause of the "dilution to salt" phenomenon. [ABSTRACT FROM AUTHOR]