Neutral Production Research Articles

Metastable Evaporation of Molecules from Water Clusters.

We probe the stability of water clusters by means of their metastable decay probability extracted from two-dimensional reflectron time-of-flight mass spectra. Two different methods are used to ionize and potentially excite the clusters and trigger the evaporation: (i) attachment of electrons with near-zero energies, producing negatively charged clusters, and (ii) electron impact ionization, producing protonated (H2O)nH+ clusters. The electron attachment is a soft ionization and therefore provides information about the size distribution of the neutral clusters in the beam due to a very limited amount of post-ionization loss of water molecules. A dependence of metastable fractions on the conditions of neutral clusters production prior to the electron attachment is reported. For the cations, the higher energy electron impact ionization leads to a more extensive metastable loss of water molecules. The results are discussed in the light of neutral cluster excitation energy distributions and, for negative clusters, also in terms of binding energies. The experiments demonstrate clearly the role of the excess electron vs the excess proton in the two different charge states of the clusters around sizes N = 50-55, for which binding energies of the anions are derived from the data.

Enhanced production, artificial intelligence optimized three-phase partitioning extraction, and in silico characterization of extracellular neutral Bacillus cereus proteinase

The present study applied atmospheric and room temperature plasma (ARTP) mutagenesis to improve Bacillus cereus strain for neutral proteinase production. The selected improved stable strain, Phe−Tyr-ARTP-60-E demonstrated a 2.88-fold enhanced proteinase yield and 2.81-fold enhanced proteinase activity with shortened fermentation time. An artificial neural network-embedded genetic algorithm (ANN-GA) was employed to optimize the enzyme's three-phase partitioning (TPP) recovery using Python software. The optimized solution of the hybrid model recommended 38.05% wv−1 (NH4)2SO4, 1.0:2.0 crude extract/tert-butanol ratio, pH 5.84 at 23.4 °C, for the exclusive partitioning of proteinase in the intermediate phase, with 202% recovery, 13-fold purity with specific activity of 922 Umg−1. Sensitivity analysis of the model revealed that enzyme recovery was most sensitive to crude extract/tert-butanol ratio with total sensitivity (ST) of 0.253 while purification factor was most sensitive to pH with an ST of 0.444. In silico analysis using Expasy ProtParam tool revealed that mutant proteinase had 3 amino acid substitutions; Val-to-Cys; Val-to-His and Ile-to-Lys, at positions 152, 288, and 292, respectively, and 39.2 kDa molecular weight, 6.42 isoelectric point, and 33.35 instability index. The 3-Dimensional structure of the enzyme predicted by ModWeb v r273 Server revealed 39% sequence identity with Pseudoalteromonas lipolytica thermolysin. The macromolecule increased transmittance in lysozyme-coated contact lenses by 99.6% in 45 min. We conclude that ARTP mutagenesis and ANN-GA optimized TPP are effective and efficient recalcitrant strain improvement and product recovery methods, respectively. Further genetic tools and analysis of the neutral proteinase-producing gene may be required for increased improvement toward sustainable application.

New μ forces from νμ sources

Accelerator-based experiments reliant on charged pion and kaon decays to produce muon-neutrino beams also deliver an associated powerful flux of muons. Therefore, these experiments can additionally be sensitive to light new particles that preferentially couple to muons and decay to visible final states on macroscopic length scales. Such particles are produced through rare 3-body meson decays in the decay pipe or via muon scattering in the beam dump, and decay in a downstream detector. To demonstrate the potential of this search strategy, we recast existing MiniBooNE and MicroBooNE studies of neutral pion production in neutrino-induced neutral-current scattering (νμN→νμNπ0,π0→γγ) to place limits on light (<2mμ) muon-philic scalar particles that decay to diphotons through loops of virtual muons. While much of this parameter space has already been excluded by E137, we also project that SBND can be sensitive to unexplored parameter space for these models, and provide a road map for future neutrino experiments to perform dedicated searches for muon-philic forces. Published by the American Physical Society 2024

Dual photocatalytic effect of Ag/TiO2 site for the total reduction of N2O and selective oxidation of alcohols to valuable carbonyl compounds

Nitrous oxide (N2O) is an important greenhouse gas emitted by anthropogenic activities, with a concentration that keeps increasing in the atmosphere. To limit its impact, thermal N2O degradation pathway is traditionally considered by main emitting actors. Nevertheless, N2O activation and upgrading as oxygen source in chemical transformations have recently received significant attention. Here, we propose to combine photocatalytic decomposition of N2O into climate neutral products N2 and H2O in the presence of primary or secondary alcohols as reducing agents. This dual reaction which simultaneously combines photoreduction of N2O and alcohols oxidation was extended to the selective transformation of alcohols into valuable ketones and aldehydes using Ag/TiO2 in acetonitrile as dual-reaction site, easily prepared by photodeposition method and loaded with only 0.3 wt% of silver.

Multilevel modelling of sustainable consumption for achieving carbon neutral production – case study of the urban in Thailand

The research aims to determine a living model that is eco-environmental and sustainable. Climate change and scarcity of resources have led world policymakers, along with the United Nations, to set guidelines in the form of 17 sustainable development goals (SDGs). Sustainable production consumption is one of the major issues that is considered worldwide, including the SDG mission of the University ranking under SDG12.The paper proposes a new model development for sustainable consumption production using multi-criteria decision-making of the Fuzzy Analytical Hierarchy Process (FAHP) under the 5P principle. The questionnaire was designed and distributed to sample populations in the community, and the analysis was done under the FAHP procedure. The research area focused on green space near Bangkok, Bang Kachao. It is one of six local governmental units (Tambon) in Phra Pradaeng district located in Samut Prakran province, Thailand.It was found out that people concerned the most sustainable production consumption using natural local materials at 25.09%, followed by making community products by green industry at 12.42% and making local green products at 6.18%. From the development of the multi-modelling framework, the paper proposes a new model of the urban community in Thailand for sustainable production consumption to support SDG12 using FAHP for multi-decision making based on the 5P principle. There are people, porosity, planet, peace, and partnership.However, various factors influence production and consumption and impact the carbon footprint.It was obviously found that people mostly use local materials to make green local products under the local policy of 3R waste management. Innovative design uses community wisdom, knowledge and know-how to make value-added products.The strategic planning and control consist of green industry, zero waste management, zero carbon footprint and innovative product design. The expected outputs from the model are green and homemade products with cleaner production, clean energy, and gain carbon credit.

Are Australian carbon prices sufficient to support decarbonisation in gas production?

Recent years have seen a rapid increase in the push for energy transition in Australia. Carbon prices have been introduced through the Safeguard Mechanism and Australian Carbon Credit Units. Consumers of hydrocarbon products are beginning to demand carbon neutral products. Oil and gas operators are pledging net-zero emissions targets. The decarbonisation efforts that ensue are expected to drive a paradigm shift in upstream development approaches. In this work, we investigate how an anonymised high carbon dioxide (CO2) gas field may be developed under prevailing carbon prices. We identify three project archetypes and estimate economically recoverable resources under each project; we also analyse the economic performance of each project. In the first archetype, we consider a project where CO2 is separated from the produced gas and vented into the atmosphere. In the second archetype, we consider a carbon sequestration project in which CO2 is transported via pipeline for storage in an onshore depleted gas reservoir. Lastly, we consider a case in which the gas buyer demands a fully carbon neutral product; as such, we study the feasibility of producing blue hydrogen using the produced gas, and how this impacts project economics and reserves. The case studies quantify by how much decarbonisation efforts negatively impact project economics and how they are the least objectionable when carbon prices are high. The analysis shows that carbon prices in Australia are currently sufficient to enable commercial development in ideal situations, but need to be higher to enable wider decarbonisation.

Exclusive production of double light neutral mesons at the e+e− colliders

In this work we investigate the exclusive production of a pair of light neutral mesons in e+e− annihilation, where the final state bears an even C-parity. The production processes can be initiated via the photon fragmentation or the nonfragmentation mechanism. While the fragmentation contribution can be rigorously accounted, the nonfragmentation contributions are calculated within the framework of collinear factorization, where only the leading-twist light-cone distribution amplitudes (LCDAs) of mesons are considered. Mediately solely by the nonfragmentation mechanism, the production rates of double light neutral pseudoscalar mesons are too small to be observed at the commissioning e+e− facilities. In contrast, the production rates of a pair of light neutral vector mesons are greatly amplified owing to the significant kinematic enhancement brought by the fragmentation mechanism. It is found that, at s=3.77 GeV, after including the destructive interference between the nonfragmentation and fragmentation contributions, the production rates for e+e−→ρ0ρ0 and ρ0ω can be lowered by about 10% and 30% relative to the fragmentation predictions. Future precise measurement of these exclusive double neutral vector meson production channels at BESIII experiment may provide useful constraints on the LCDAs of light vector mesons. Published by the American Physical Society 2024

Feasibility study on preloaded flexible conical plain bearings as wind turbine main bearings

Wind turbines (WT) are a key technology towards a carbon neutral energy production worldwide. Currently about 30 % of the Levelized Cost of Electricity (LCoE) consist of service and maintenance. Critical components are the main roller bearings which have a failure probability between 15 and 30 % within 20 years. Main bearing replacements are expensive maintenance procedures because an external crane is needed which cost about $250.000 per day for offshore WTs. Hence, a discussed countermeasure within the wind industry is to use segmented plain bearings in future WTs. These types of bearings allow an up-tower sub-component wise replacement of faulty parts without the need to dismantle the whole drivetrain. Therefore, the Chair for Wind Power Drives (CWD) developed, tested and validated a segmented conical plain bearing concept for the use as a main bearings for WTs. To function properly common plain bearings need a minimum clearance to allow the formation of a convergent lubrication gab. This initial clearance negatively influences run-out, as the shaft con move freely within the limits of the clearance. As WT drivetrain concepts become more integrated, main bearings for WTs need to fulfill higher requirements regarding the allowable run-out of the main shaft. Therefore, a fundamental design challenge arises for plain bearings as rotor main bearings. One approach to reduce run-out for roller main bearings is to use preloaded tapered roller bearings. For common plain bearings however preloading is not possible. However, the concept of preloading was successfully transferred to the flexible conical plain bearing concept developed at the CWD and the main shaft run-out severely reduced. In this work the feasibility of a preloaded flexible conical plain bearing as a WT rotor main bearing is evaluated and the advantages and disadvantages contrasted.

Enhancing the methanol yield of industrial-scale fixed bed reactors using computational fluid dynamics models

Achieving our decarbonisation goals for the maritime transport sector requires the bulk production of liquid hydrocarbon fuels, suitable for the existing infrastructure, such as methanol (MeOH). For this, optimisation of fixed bed chemical reactors is vital. Unlike demonstration-scale setups, optimising the design of such reactors using Computational Fluid Dynamics (CFD) models is both cheaper and faster. In this study, using a 2D pseudo-homogeneous CFD model, a single tube from a multi-tubular industrial-scale MeOH reactor is simulated. Using available experimental data, the CFD model was validated yielding excellent accuracy, with an average error of 2.6 %. The model identified a temperature hot-spot near the bed entrance, while the predicted pressure drop was 11 % of the operating pressure. Both effects could considerably reduce the efficiency of the reactor, either by catalyst deactivation or by increasing the compressor requirements, respectively. Through a parametric study where the tube’s length and diameter were varied within the ±50 % range, 53 total cases are produced and solved, creating an extensive pareto set of data for the key output parameters, such as methanol production, pressure, and temperature. A response surface was also generated, revealing the interconnection between the tube’s design and the operating parameters. This enabled a performance optimisation of the reactor design for two industrially relevant scenarios, with the optimised reactor achieving a 6.9 % higher MeOH yield and a 75 % reduced pressure drop. Through industrial involvement, the reactor can be further optimised, and would act as a critical foundation for more extensive techno-economic and socio-economic evaluations for sustainable carbon–neutral methanol production.

Biotechnological Processing of Sugarcane Bagasse through Solid-State Fermentation with White Rot Fungi into Nutritionally Rich and Digestible Ruminant Feed

Sugarcane (Saccharum officinarum) bagasse (SCB) is one of the most widely produced lignocellulosic biomasses and has great potential to be recycled for sustainable food production as ruminant animal feed. However, due to severe lignification, i.e., lignin-(hemi)-cellulose complexes, ruminants can only ferment a minor fraction of the polysaccharides trapped in such recalcitrant lignocellulosic biomasses. This study was therefore designed to systematically evaluate the improvement in nutritional value, the in vitro dry matter digestibility (IVDMD), and the rate and extent of in vitro total gas (IVGP) and methane (CH4) production during the 72 h in vitro ruminal fermentation of SCB, bioprocessed with Agaricus bisporus, Pleurotus djamor, Calocybe indica and Pleurotus ostreatus under solid-state fermentation (SSF) for 0, 21 and 56 days. The contents of neutral detergent fiber, lignin, hemicellulose and CH4 production (% of IVGP) decreased (p < 0.05), whereas crude protein (CP), IVDMD and total IVGP increased (p < 0.05) after the treatment of SCB for 21 and 56 days with all white-rot fungi (WRF) species. The greatest (p < 0.05) improvement in CP (104.1%), IVDMD (38.8%) and IVGP (49.24%) and the greatest (p < 0.05) reduction in lignin (49.3%) and CH4 (23.2%) fractions in total IVGP were recorded for SCB treated with C. indica for 56 days. Notably, C. indica degraded more than (p < 0.05) lignin and caused greater (p < 0.05) improvement in IVDMD than those recorded for other WRF species after 56 days. The increase in IVGP was strongly associated with lignin degradation (R2 = 0.72) and a decrease in the lignin-to-cellulose ratio (R2 = 0.95) during the bioprocessing of SCB. Our results demonstrated that treatment of SCB with (selective) lignin-degrading WRF can improve the nutritional value and digestibility of SCB, and C. indica presents excellent prospects for the rapid, selective and more extensive degradation of lignin and, as such, for the improvement in nutritional value and digestibility of SCB for ruminant nutrition.

Interfacial chemical reactivity enhancement.

Interfacial enhancements of chemical reaction equilibria and rates in liquid droplets are predicted using a combined theoretical and experimental analysis strategy. Self-consistent solutions of reaction and adsorption equilibria indicate that interfacial reactivity enhancement is driven primarily by the adsorption free energy of the product (or activated complex). Reactant surface activity has a smaller indirect influence on reactivity due to compensating reactant interfacial concentration and adsorption free energy changes, as well as adsorption-induced depletion of the droplet core. Experimental air-water interfacial adsorption free energies and critical micelle concentration correlations provide quantitative surface activity estimates as a function of molecular structure, predicting an increase in interfacial reactivity with increasing product size and decreasing product polarity, aromaticity, and charge (but less so for anions than cations). Reactions with small, neutral, or charged products are predicted to have little reactivity enhancement at an air-water interface unless the product is rendered sufficiently surface active by, for example, interactions with interfacial water dangling OH groups, charge transfer, or voltage fluctuations.

Extensive functional connectivity between brain areas implicated in mental imagery production and phobic fear during both emotional and neutral mental imagery

Mental imagery is used by most people in their day-to-day cognition, for example, in planning, daydreaming, or remembering. Importantly, mental imagery has a powerful influence on emotion and is critically involved in many mental disorders. Thus, understanding the link between mental imagery and emotion is of clinical interest. For example, exposure therapy can be successfully conducted using mental imagery of fear-provoking stimuli, i.e., imaginal exposure. In this vein, accumulating evidence shows that mental imagery of a fearful stimulus produces a similar physiological and neural response as actual perception of the stimulus. Alas, knowledge of the neural processes underlying the link between mental imagery and emotion is limited. Functional magnetic resonance imaging data from a previous study on imaginal exposure (N = 30) was used to examine the functional connectivity during the production of phobic and neutral mental imagery. Regions of interest were selected from meta-analyses on brain regions consistently recruited during mental imagery production and phobic fear, respectively. Results showed that these regions were positively correlated during both phobic and neutral mental imagery production. Very few differences in functional connectivity between phobic and neutral imagery were found. Specifically, weaker functional connectivity between the supplemental motor area and a region including parts of the left insula and inferior frontal gyrus was observed during phobic (vs neutral) imagery. In conclusion, our findings suggest that brain regions previously implicated in mental imagery production and phobic fear are highly interconnected during the production of both phobic and neutral imagery.

Effect of a critical magnetic field on the control of scalar neutral boson pair production in the context of Lorentz-symmetry violation

This study investigates the production of neutral scalar boson pairs in static electromagnetic fields resulting from Lorentz-symmetry violation (LSV), with a focus on the parity-even sector of the CPT-even photon sector in the Standard Model Extension (SME). Utilizing a cross-configuration involving inhomogeneous static electric fields and homogeneous static magnetic fields, the analysis of the probability of bosons pair production identifies three different regimes determined by a critical magnetic field. Below the critical value, creation is exponentially suppressed; at the critical value, the number density of created bosons remains constant, and above the critical field, there is exponential amplification. This behavior prompts an additional investigation using von Neumann entanglement entropy to analyze fluctuations in the bosonic vacuum.

The mutual neutralization of hydronium and hydroxide.

Mutual neutralization of hydronium (H3O+) and hydroxide (OH-) ions is a very fundamental chemical reaction. Yet, there is only limited experimental evidence about the underlying reaction mechanisms. Here, we report three-dimensional imaging of coincident neutral products of mutual-neutralization reactions at low collision energies of cold and isolated ions in the cryogenic double electrostatic ion-beam storage ring (DESIREE). We identified predominant H2O + OH + H and 2OH + H2 product channels and attributed them to an electron-transfer mechanism, whereas a minor contribution of H2O + H2O with high internal excitation was attributed to proton transfer. The reported mechanism-resolved internal product excitation, as well as collision-energy and initial ion-temperature dependence, provide a benchmark for modeling charge-transfer mechanisms.

Study of a Method for Neutralizing the Hydrocarbon-based Drilled Cuttings

The results of studies of the mechanical and chemical-toxicological properties of hydrocarbon-based drilled cuttings during the firing process at various temperature conditions are presented. Changes in the mineralogical composition, gross content of heavy metals, content of chloride, phosphate, sulfate ions and petroleum products, as well as the level of toxicity were studied. The indicators of the neutralization product were determined: water absorption capacity, strength, loss of strength in a water-saturated state. A technological scheme for the process of neutralizing the drilled cuttings with production of an environmentally friendly building material that can replace a part of the imported natural materials is described.

Tacrolimus impairs airway mucociliary clearance of rats

ObjectivesTacrolimus (TAC) is the most widely used immunosuppressive agent after lung transplantation. Considering that the ciliary beat frequency (CBF) mainly depends on the cytoplasmic calcium concentration and that TAC can affect this due to its binding with the intracellular immunophilin FKBP12, we hypothesized that TAC could also impair the airway mucociliary clearance of rats. MethodsSixty rats were divided into two groups (n = 30 each): Control = water; TAC = tacrolimus. After 7, 15 or 30 days of treatment, ten animals from each group were euthanized and the following parameters were studied: mucus transportability, CBF, mucociliary transport velocity (MCTV), and neutral and acid mucus production. ResultsThere was a significant decrease in CBF (Control vs TAC: 7 days, p = 0.008; 15 days, p = 0.007; 30 days, p = 0.001) and MCTV (Control vs TAC: 7 days, p = 0.004; 15 days, p < 0.001; 30 days, p < 0.001) in all immunosuppressed animals. TAC therapy also caused an increase in acid mucus production at all treatment times (Control vs TAC: 7 days, p = 0.001; 15 days, p = 0.043; 30 days, p = 0.001). ConclusionsTAC impairs airway mucociliary clearance of rats.

DarkNews: A Python-based event generator for heavy neutral lepton production in neutrino-nucleus scattering

We introduce DarkNews, a lightweight Python -based Monte-Carlo generator for beyond-the-Standard-Model neutrino-nucleus scattering. The generator handles the production and decay of heavy neutral leptons via additional vector or scalar mediators, as well as through transition magnetic moments. DarkNews samples pre-computed neutrino-nucleus upscattering cross sections and heavy neutrino decay rates to produce dilepton and single-photon events in accelerator neutrino experiments. We present two case studies with differential distributions for models that can explain the MiniBooNE excess. The aim of this code is to aid the neutrino theory and experimental communities in performing searches and sensitivity studies for new particles produced in neutrino upscattering. Program summaryProgram Title: DarkNewsCPC Library link to program files:https://doi.org/10.17632/k9nh5fn4pw.1Developer's repository link:https://github.com/mhostert/DarkNews-generatorLicensing provisions: MITProgramming language: PythonNature of problem: In many theories beyond the Standard Model of particle physics, new light particles are introduced with masses below the 100 GeV scale. These can be produced by neutrino-nucleus interactions inside neutrino detectors, leaving a visible signature through their decay. To search for these signatures, experiments have to simulate the underlying physical processes, which requires detailed knowledge of the cross sections and decay rates in the model, as well as the ability to generate Monte Carlo events.Solution method: DarkNews provides the necessary tools to simulate the production of heavy neutral leptons in accelerator neutrino experiments, focusing on neutrino-nucleus scattering processes. The program's scope includes models with new mediators and three heavy neutral leptons, parameterizing a large class of theories through generic neutrino, quark, and lepton interactions. It generates weighted Monte-Carlo events using vegas and its pre-calculated differential rates.

Histochemical and morphological evaluation of a glyoxal acid-free fixative

ABSTRACT The application of most chemical fixatives, such as formalin, in the anatomic pathology laboratory requires safety training and hazardous chemical monitoring due to the toxicity and health risks associated with their use. Consequently, the use of formalin has been banned in most applications in Europe; the primary exception is its use in the histology laboratory in lieu of a suitable and safer alternative. Glyoxal based solutions, several of which are available commercially, are the most promising alternative fixatives, because they are based on a mechanism of fixation similar to that of formalin. Unlike formalin, however, glyoxal based solutions do not dissociate from water and therefore do not require ventilation measures such as a fume hood. A primary barrier to the adoption of commercially available glyoxal based solutions is their low pH, which can produce undesirable morphological and antigenic tissue alterations; however, a recently available neutral pH glyoxal product (glyoxal acid free) (GAF) has been developed to mitigate the challenges of low pH. We compared the morphology and histochemistry among tissues fixed in 10% neutral buffered formalin, a commercially available acidic glyoxal product (Prefer), and GAF. Tissues fixed in formalin and Prefer exhibited similar morphology and staining properties; tissues fixed with 2% GAF exhibited deleterious effects.

F-Block reactions of metal cations with carbon dioxide studied by inductively coupled plasma tandem mass spectrometry.

f-Block chemistry offers an opportunity to test current knowledge of chemical reactivity. The energy dependence of lanthanide cation (Ln+ = Ce+, Pr+, Nd+-Eu+) and actinide cation (An+ = Th+, U+-Am+) oxidation reactions by CO2, was observed by inductively coupled plasma tandem mass spectrometry. This reaction is commonly spin-unallowed because the neutral reactant (CO2, 1Σ+g) and product (CO, 1Σ+) require the metal and metal oxide cations to have the same spin state. Correlation of the promotion energy (Ep) to the first state with two free d-electrons with the reaction efficiency indicates that spin conservation is not a primary factor in the reaction rate. The Ep likely influences the reaction rate by partially setting the crossing between the ground and reactive states. Comparison of Ln+ and An+ congener reactivity indicates that the 5f-orbitals play a small role in the An+ reactions.

Enhancing neutral hydrogen production by disrupting the rigid hydrogen bond network on Ru nanoclusters through Nb2O5-mediated water reorientation

Nb2O5 with a negative charge can disrupt the rigid H-bond network on the surface of Ru nanoclusters, making it easier for free water molecules to reach the catalyst, thus accelerating the reactivity of hydrogen reduction.