Bath Temperature Research Articles

Inclusion of W in electroless Ni–B coating developed from a stabilizer free bath and investigation of its tribological behaviour

In the present study, tribological and corrosion behaviour of electroless Ni–B–W (ENB-W) coatings prepared from stabilizer-free baths and deposited on AISI 1040 steel substrates were examined. Three distinct coating bath temperatures (85 °C, 90 °C, and 95 °C) were varied for coating deposition. The coatings showed nodular morphology. Thermogravimetric study of ENB-W coatings revealed improved thermal stability attained at 95 °C bath temperature. The microhardness of ENB-W coating was 645, 690, and 720 HV100 at bath temperatures of 85 °C, 90 °C, and 95 °C respectively. The inclusion of W to Ni–B coating enhanced the hardness by ∼150 HV100. On a pin-on-disc tribometer, wear test was conducted. The precipitation of Ni (111) and its borides occurred post sliding wear at high temperatures (300 °C). Ni (111) crystallite size decreased because of high temperature sliding wear at 300 °C with an increase in coating bath temperature. With a reduction in crystallite size at high temperatures, both wear rate and COF decreases. The scratch hardness and first critical load of failure of the coatings was determined using a scratch tester. Using potentiodynamic polarization, corrosion resistance of ENB-W coatings in 3.5% NaCl was investigated. ENB-W coatings could provide shielding to AISI 1040 steel from corrosion. Though the corrosion resistance is poor with respect to lead stabilized coatings.

New protocol for functionalization of fullerene soot with dinitrobenzene groups from a non-diazonium resource

The nitrobenzene functionalized fullerene soot has been considered as a potentially energetic material. In our previous study, the in situ produced nitrobenzene diazonium ions have been used for the synthesis of 2-nitrobenzene, 4-nitrobenzene and 2,4-dinitrobenzene functionalized fullerene soot nanoparticles with moderate oxygen (14.91 wt%) and nitrogen (6.27 wt%) contents. In the present study, a new protocol for the functionalization of fullerene soot with 3,5-dinitrobenzene groups from a non-diazonium resource is reported. The functionalization of fullerene soot is performed through Ag(I)-catalyzed decarboxylative oxidation of 3,5-dinitrobenzoic acid (DNBA) under conventional heating or microwave irradiation. The effects of various parameters such as the oil bath temperature and the amounts of substrate (DNBA), catalyst (AgNO3) and oxidant (K2S2O8) on these reactions are evaluated. The synthesized compounds are characterized by FT-IR, Raman, XRD, SEM-EDX and elemental mapping analysis, FE-SEM and TEM along with particle size analysis, as well as TGA-DSC. The DSC thermograms of functionalized fullerene soot show a single exothermic peak attributed to the exothermic decomposition of 3,5-dinitrobenzene groups. Some of these compounds have up to 82.16 wt% oxygen and 6.10 wt% nitrogen contents. These findings are important for development of the energetic materials with improved oxygen content.

A numerical investigation of methane pyrolysis in a molten catalyst Bath–A single bubble approach

A dynamic one-dimensional numerical model of methane pyrolysis within a rising and pyrolysing bubble in a column of molten Ni0.27Bi0.73, as a molten catalyst, is presented. The model predicts both the behavior of the rising bubble in the column and the chemical reactions within it, accounting for any variations in bubble diameter and rising velocity, which have previously been assumed to be constant. The conservation equations of energy, mass and momentum are solved simultaneously using the implicit Gauss–Seidel numerical method. The model accounts for the main parameters contributing to the methane pyrolysis reaction. The reliability of the model was assessed by comparison with the available experimental data from the literature and a reasonable agreement was found. Considering the model assumptions, the results show that, for the assessed conditions, more than 97% of the overall conversion occurs at the interface of the bubble and the molten bath, while the reaction within the bubble contributes only <3% of the overall conversion. A sensitivity analysis was also undertaken to the variations in the bubble size, column height, molten bath temperature, pressure, gas composition and temperature. Calculations show that methane conversion is more sensitive to the molten bath temperature than the initial gas temperature. Furthermore, it decreases significantly with any increase in pressure. Also, at pressures of > 2 MPa, the equilibrium condition is achieved within the bottom one-third of the column for the assessed conditions.

Effects of bath temperature on the properties of chemical bath-deposited FeSxOy films

Effects of bath temperature on the properties of chemical bath-deposited FeSxOy films

Electrochemical noise energy generated by nickel electroplating process

AbstractThe effects of current density (Jk) and bath temperature on the structure of deposition layer of nickel and electrochemical noise energy (ED) are studied, and the relationship between the structure of the deposit and ED is also discussed in detail using electrochemical noise technique in coupled with the scanning electron microscopy and the glancing angle X-ray diffraction techniques. The results show that ED theoretically mainly reflects the severity or rate of the local cathodic reaction rather than the integral cathodic reaction, and is markedly influenced by the electroplating current density (Jk)-depended nucleation/growth kinetics of the nickel deposit film. The proceeding of the nucleation (or the formation of new phase)/growth process of crystal nucleus on a foreign substrate possesses much more effect on ED value than the subsequent homogenous growth of the already formed film particles, and the factors which can accelerate the drastic change of the electrode surface state should result in large ED value.

Entanglement negativity in a nonequilibrium steady state

We study entanglement properties in a nonequilibrium steady state of a free-fermion chain, that emerges after connecting two half-chains prepared at different temperatures. The entanglement negativity and the R\'enyi mutual information between two adjacent intervals scale logarithmically in the system size, with prefactors that we calculate analytically as a function of the bath temperatures. In particular, we show that the negativity and the R\'enyi mutual information with index $\ensuremath{\alpha}=1/2$ are described by different prefactors, and thus the two quantities provide inequivalent information about the state. Furthermore, we show that the logarithmic growth of the negativity during time evolution is also governed by the steady-state prefactor.

Higgs boson induced reheating and ultraviolet frozen-in dark matter

A reheating phase in the early universe is an essential part of all inflationary models during which not only the Standard Model (SM) quanta are produced but it can also shed light on the production of dark matter. In this work, we explore a class of reheating models where the reheating is induced by a cubic interaction of the inflaton ϕ to the SM Higgs boson h of the form ghϕMPlϕ|h|2 adopting the α-attractor T-model of inflation. Assuming inflaton as a background field such interaction implies a ϕ-dependent mass term of the Higgs boson and a non-trivial phase-space suppression of the reheating efficiency. As a consequence, the reheating is prolonged and the maximal temperature of the SM thermal bath is reduced. In particular, due to oscillations of the inflaton field the ϕ-dependent Higgs boson mass results in periodic transitions between phases of broken and unbroken electroweak gauge symmetry. The consequences of these rapid phase transitions have been studied in detail. A purely gravitational reheating mechanism in the presence of the inflaton background, i.e., for ghϕ = 0, has also been investigated. It turned out that even though it may account for the total production of SM radiation in the absence of ghϕ, its contribution to the reheating is subdominant for the range of ghϕ considered in this work. Approximate analytical solutions of Boltzmann equations for energy densities of the inflaton and SM radiation have been obtained. As a dark matter candidate a massive Abelian vector boson, Xμ, has been considered. Various production mechanisms of Xμ have been discussed including (i) purely gravitational production from the inflaton background, (ii) gravitational freeze-in from the SM quanta, (iii) inflaton decay through a dim-5 effective operator, and (iv) Higgs portal freeze-in and Higgs decay through a dim-6 effective operator. Parameters that properly describe the observed relic abundance have been determined.

Thermodynamics of Quantum Spin-Bath Depolarization.

We analyze here through exact calculations the thermodynamical effects in depolarizing a quantum spin-bath initially at zero temperature through a quantum probe coupled to an infinite temperature bath by evaluating the heat and entropy changes. We show that the correlations induced in the bath during the depolarizing process does not allow for the entropy of the bath to increase towards its maximal limit. On the contrary, the energy deposited in the bath can be completely extracted in a finite time. We explore these findings through an exactly solvable central spin model, wherein a central spin-1/2 system is homogeneously coupled to a bath of identical spins. Further, we show that, upon destroying these unwanted correlations, we boost the rate of both energy extraction and entropy towards their limiting values. We envisage that these studies are relevant for quantum battery research wherein both charging and discharging processes are key to characterizing the battery performance.

Enhanced crude oil degradation by remodeling of crude oil-contaminated soil microbial community structure using sodium alginate/graphene oxide/Bacillus C5 immobilized pellets

Bioaugmentation (BA) of oil-contaminated soil by immobilized microorganisms is considered to be a promising technology. However, available high-efficiency microbial agents remain very limited. Therefore, we prepared a SA/GO/C5 immobilized gel pellets by embedding the highly efficient crude oil degrading bacteria Bacillus C5 in the SA/GO composite material. The optimum preparation conditions of SA/GO/C5 immobilized gel pellets were: SA 3.0%, GO 25.0 μg/mL, embedding amount of C5 6%, water bath temperature of 50°C, CaCl2 solution concentration 3% and cross-linking time 20 h. BA experiments were carried out on crude oil contaminated soil to explore the removal effect of SA/GO/C5 immobilized pellets. The results showed that the SA/GO/C5 pellets exhibited excellent mechanical strength and specific surface area, which facilitated the attachment and growth of the Bacillus C5. Compared with free bacteria C5, the addition of SA/GO/C5 significantly promoted the removal of crude oil in soil, reaching 64.92% after 30 d, which was 2.1 times the removal rate of C5. The addition of SA/GO/C5 promoted the abundance of soil exogenous Bacillus C5 and indigenous crude oil degrading bacteria Alcanivorax and Marinobacter. In addition, the enrichment of hydrocarbon degradation-related functional abundance was predicted by PICRUSt2 in the SA/GO/C5 treatment group. This study demonstrated that SA/GO/C5 is an effective method for remediating crude oil-contaminated soil, providing a basis and option for immobilized microorganisms bioaugmentation to remediate organic contaminated soil.

Electrodeposition of SnO2 nanostructures onto copper substrates and their electrochemical properties

Potentiostatic electrodeposition of SnO2 thin films from an oxygenated tin chloride bath on anodised copper substrates has been achieved at a bath temperature of 85 °C. At the bath temperature of 85 °C, the evolution of nanoplates, nanoparticles and nanocubes are observed. Aqueous battery and bio-sensing characteristics of the SnO2 nanostructures were assessed. The electrodes are cycled between –1 and +1 V in LiOH . H2O, Li2CO3 and Na2SO4 electrolyte solutions by cyclic voltammetry method. The test results exhibit that the nanocrystalline SnO2 anode is a proficient electrode material for the aqueous lithium battery. Electrochemical detection of ascorbic acid (AA) on the nanostructured SnO2 electrode has also been assessed and SnO2 nanocubes displayed eminent electro catalytic activity towards the oxidation of AA.

Study on the Technology of Grapefruit Capsules Removement by Enzymatic

&lt;p&gt;Taking grapefruit as the experimental raw material, the fruit kernel integrity and extraction rate were comprehensively evaluated, and the grapefruit enzymatic de-coating process was explored to provide a basis for the industrial production of grapefruit fruit. The enzymatic de-coating process parameters were optimized by orthogonal test. The results showed that the water bath temperature was 40℃, the total amount of pectinase and cellulase was 1.25 mL, Study on the Technology of Grapefruit Capsules Removement by Enzymatic the ratio was 1:3, and the ratio of material to liquid (West) When the ratio of pomelo and mixed enzyme solution was 80g/100mL, the effect of decapsulation was the best. The grapefruit obtained in this case was relatively complete, and the extraction rate reached 93%.&lt;/p&gt;

DEPOSITING Ni–Co–P ALLOY COATING ON AISI316 STEEL AND ANALYZING ITS PROPERTIES

After appropriately preparing the surface of AISI316 steel, the Ni–Co–P coating layer was deposited on the substrate using the electroless method using baths with different mole ratios of CoSO4/NiSO[Formula: see text]. Coating rate, weight percentage of the alloy elements, corrosion rate and coating layer hardness were studied in the achieved coating layers. The coating rate of the Ni–Co–P coating layer is a function of the mole ratio of CoSO4/CoSO[Formula: see text], sodium hypophosphite concentration, bath temperature, bath pH and plating time. The electroless deposits studied in this paper are in crystal form. The XRD pattern of the Ni–Co–P deposits shows the peaks related to Ni-fcc and tetragonal Ni[Formula: see text]P5. X-ray diffraction pattern confirms the formation of the Ni3P phase during annealing for 1[Formula: see text]h at 400∘C.

Kinetic Temperature of Structures for Resilience, Instability, and Failure Analysis of Building Systems

From theory, calibration and application of the equipartition theorem of statistical physics to structural failure and instability analysis, we introduce the kinetic temperature of structures as an order parameter to ascertain equilibrium and out-of-equilibrium states in structural mechanics. Set within the framework of molecular dynamics-based structural mechanics, this is achieved by connecting the set of momentum balance equations to an outside bath reservoir maintained at a reference temperature history through the Nosé-Hoover thermostat. The problem thus comes down to solving the momentum balance equation with a dissipative mass damping term, which evolves in function of the difference in temperature between the structure’s kinetic temperature/energy and the bath temperature. Following the Zeroth Law of Thermodynamics, it is recognized that a structure is in (thermal) equilibrium as long as the structure’s kinetic temperature attains the bath temperature; whereas it is out-of-equilibrium when the open system (structure plus bath) exhibits a sustained temperature difference. In this case, the structure has exhausted its fluctuation-dissipation capacity, which is indicative—for structures—of a progressive failure and instability. The implementation of the kinetic temperature as an order parameter in structural failure and instability analysis is illustrated for a prototype five-storey building subject to excessive wind and fire loads. It is suggested that the proposed order parameter becomes an integral part of the structural engineering toolbox for resilience studies of buildings and structures.

Computational and experimental studies on SnO2 thin films at various temperatures

Tin oxide (SnO2) thin films was prepared by dip-coating technique at various bath temperatures (313, 333, 353 and 373 K) and annealed at 673 K in this study. And the obtained results were studied and correlated with the computational method. Scanning electron microscopy (SEM) investigation demonstrated that the prepared samples are spherical with agglomeration. The elemental analysis (EDAX) confirms the presence of Sn and O. Further, the SnO2 thin films microstructures are simulated, their thermodynamic and surface properties have been calculated. Micro-Raman spectra were recorded for the prepared samples. Micro-Raman results exhibit the first-order Raman mode E1gsub&gt; (475 cm−1) indicating that the grown SnO2 belongs to the rutile structure. In addition, the envelope method used for studying optical characteristics of the thin films from the transmittance spectra. The semiconducting nature of the films has been noticed from linear I-V characteristics. Furthermore, the electrical conductivity studies suggest that the highest conductivity samples acquire the lowest activation energy and their values are also in the semiconducting range.

Tuning the temperature dependence of Shaker potassium channel with mutations at S4-S5 linker.

We investigated the effects of temperature on mutations that uncouple the voltage sensor (VSD) from the pore (PD) in the Shaker-IR potassium channel using temperature step (Tstep). We utilized a setup that achieves fast temperature changes (millisecond) and allows the recording of the cell membrane temperature with sub-millisecond resolution (https://doi.org/10.1101/2022.07.11.499616). We used the mutants V369I, I372L, S376T (ILT), in the N-terminus of the S4-S5, that produces a split in the components of the gating charge movement, and I384N, near the S4-S5 C-terminus, that uncouples the VSD charge movement from the PD. From a bath temperature of 17 ºC, we used a Tstep of around ∼9 ºC with rising phase of 1.5 ms. In ILT, applying a Tstep, after the gating currents have subsided, promotes a right shift in the first component of gating charge and a left shift of the second component (the last concerted step associated with PD opening). Consistently, Tstep applied after the onset of a depolarizing voltage pulse produces a ∼5 mV left shift in the conductance-voltage curve (G-V). The entropy, calculated from G-V, changes from 24 for WT to −42 J/K for ILT. In I384N, applying a Tstep reduces the ionic current indicating the closure of the pore. We hypothesize that the temperature dependence of the ILT G-V arises from the changes in the last step of the charge movement. On the other hand, since the VSD and PD are loosely coupled in I384N, the increase in temperature is likely to further decrease the VSD-PD coupling, thus decreasing the measured conductance. (Support: NIH: GM030376, Fondecyt: 1190203)

A meta‐analytic review of monoterpene for fish anaesthesia

AbstractThe use of anaesthetic agents has been increasing to address the welfare needs of different fish species in scientific and aquaculture practices. MS‐222 is the most used synthetic anaesthetic but some limitations and side effects have been reported. Natural substances have been used as potential substitutes with clove oil playing an important role due to its eugenol content. Yet, other monoterpenes have shown anaesthetic properties in different fish species. As such, a quantitative assessment has been conducted to explicitly relate and summarise the use of monoterpenes with described anaesthetic properties in fish. A combined PubMed, Web of Science, Scopus, PubMed Central and Europe PMC electronic database search was performed, from January 2002 to August 2022, following the PRISMA guidelines. Out of 1555 articles retrieved from the literature search, 30 English reports met the criteria for inclusion in the meta‐analysis through a generic inverse‐variance method (random‐effects model) and according to the fish age. The findings show a total of 10 different monoterpenes with high homogeneity and effectiveness in inducing anaesthesia and recovery according to the fish anaesthetic criteria. Further subgroup analysis showed these effects were independent of fish age. Meta‐regression of the included studies revealed an inverse linear association between anaesthesia induction and recovery time and water bath temperature while no further correlation was found with other confounding factors (body weight, water pH and dissolved oxygen levels). Although further studies will be required, this meta‐analysis provides robust evidence that different monoterpenes serve as an attractive and effective alternative for fish anaesthesia although water bath temperature also played an important role in anaesthesia outcome.

Effect of quantitative heat transfer performance on the separation and enrichment of bio-oil components during the selective condensation of biomass pyrolysis vapors

A quantitative analysis method combining experimental measurement with simulation calculation was proposed for analyzing heat exchange performance during the selective condensation of biomass pyrolysis vapors. The quantitative mechanism of sensible heat and latent heat released from vapor condensation on the separation and enrichment of bio-oil components was analyzed under the regulation of water bath. As the bath temperature increased from 273 K to 363 K, the sensible heat proportion of water decreased from 46.3% to 44.5% but its latent heat proportion decreased from 80% to 55%, causing 90% reduction in bio-oil moisture, whereas the contents of guaiacol and its derivatives were improved by 50–200% because their sensible heat proportion increased from 5.7% to 6.1% and the latent heat proportion increased from 2% to 25%. Each −1% decrease in the separation rate of water required 0.2244% decrease in the total heat exchange proportion while each 1% increase in the enrichment rate of guaiacol compounds required 0.0346% increase in the total proportion. The unified analysis standard for the various apparent parameters of condensation was established through grasping the quantitative relationship between heat exchange performance and componential content, which effectively promoted the conversion of selective condensation under different scales or conditions.

Feasible pathways for the multi-dimensional synthesis of carboxylic acid from benzo-pyrone methyl ketone

3-Acetyl coumarin derivatives are the key synthons to the numerous numbers of heterocyclic compound syntheses. Due to the wide spectrum applications of benzopyran derivatives in pharma, research, food technology and material science there is a multitude number of methodologies feasible to synthesize benzo pyrone heterocyclic derivatives. This article articulates the synthesis and molecular structure confirmation of oxidative product starting from methyl ketone compound by haloform reaction. Design of benign path ways for instance room temperature, reflux conditions and water bath mediated synthesis of desired compounds in expected yields is the foremost intent of the article. Solvent and catalyst optimization studies were carried to elevate the product yield and to precede the reaction in sustainable way. Furthermore compounds are confirmed by spectroscopic analytical methods such as 1 HNMR, 13 CNMR, IR and HRMS spectroscopy. This article paves the way to researchers to explore these analogues to explore disparate medicinal applications.

Design and Development of Plantain Fibre for Application in Production of Oil and Gas Facilities

This research established reasons why industries, especially in the oil and gas are looking at plantain fibre which is a natural fibre composite due to low price, weight reduction, easy to recycle and are green in nature and so on; when compared to petroleum-based fibres. The plantain will be cut, retted, extracted, dried, treated, and modified. The tensile, hardness properties of untreated and treated plantain fibres as well as their densities will be investigated. The fibres developed in the research exhibit good mechanical properties in terms of tensile strength, hardness and density. These treatments improved the hydrophobic property of the developed fibre, the density of the untreated and alkali treated fibre gave 0.021g/cm³ and 0.040 g/cm³. The test conducted for strength on the mercerization treated fibres dried at different oven temperature of 30°C, 50°C, 70°C using 50mm, 60mm and 70mm fibre length. Based on the experimental results, oven temperature of 70°C at 80mm fibre length gave the highest strength of 706Mpa for mercerization treated fibre. At 50°C oven drying temperature gave 689Mpa using 50mm fibre length. At temperature of 30°C gave 682Mpa using 80mm fibre length. The mercerization modified fibre on 10% NaOH concentration at temperature of 70°C gave the optimum highest strength of 706Mpa at 80mm fibre length. Based on the results, the 70°C oven bath temperature is therefore adopted and accepted as the benchmark for developing the fibre. The developed fibre composite can be reinforced for production of test samples and products of oil and gas component such as piping, pipeline systems and pressure vessels among others.

Rapid Electrodeposition and Corrosion Behavior of Zn Coating from a Designed Deep Eutectic Solvent

This work aimed to develop a new type of deep eutectic solvent containing high concentrations of zinc ions as an electrolyte to improve the electrodeposition rate for zinc plating. Two typical deep eutectic solvent systems, choline chloride (ChCl)–urea and ChCl–ethylene glycol (EG), were combined to prepare a stable electrolyte at room temperature with a zinc ion concentration up to 2 M. Cyclic voltammetry experiments of the electrolyte at different temperatures were conducted. The effects of key electrodeposition parameters (bath temperature and current density) on the morphology, structure, and corrosion resistance of zinc coatings deposited on mild steel were investigated. It was found that the crystal orientation of the as-deposited zinc particle is related to the electrodeposition temperature and current density. The experimental results show that the zinc coating deposited at 60 °C and the current density of 4 mA·cm−2 exhibited the most compact and crack-free morphology, thus had the optimum corrosion resistance property.