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Bandung, Indonesia, represents the complex interactions between climate variability, basin topography, and deposition processes. This study conducted a long-term spatiotemporal analysis, including pH distribution and pollutant accumulation monitoring, to observe the chemical composition of wet deposition in Bandung as part of the Acid Deposition Monitoring Network in East Asia (EANET). The results revealed that NH 4 + and NO 3 - were the predominant ions, followed by SO 4 2 - , with their distribution varying across different sites due to local emissions and atmospheric processes. The interactions between these ions, particularly the formation of secondary inorganic aerosols such as ammonium sulfate and ammonium nitrate, were closely linked to the basin's localized sources and topographical features. Areas experiencing high traffic congestion were classified as acidic regions due to their low pH levels. In contrast, a rural site exhibited a basic pH due to the high concentration of ion NH 4 + . Variations in pH and conductivity, along with the impacts of climatic events such as El Niño and La Niña, emphasized the role of weather patterns in shaping wet deposition dynamics. Seasonal trends indicated elevated total ion concentrations during the dry season, driven by sea salt contributions, as supported by strong correlations between Na+ and Cl - and between Na+ and Mg2+. Additionally, geological materials and atmospheric reactions contributed to the strong correlations observed between soil-derived cations and acidic species. The increasing trend in nss - SO 4 2 - and the contrasting decrease in NO 3 - concentrations in rural areas suggest evolving emission sources and environmental conditions. [ABSTRACT FROM AUTHOR]

Rate constants for the reactions of C+ + Cl−, Br−, and I− were measured at 300 K using the variable electron and neutral density electron attachment mass spectrometry technique in a flowing afterglow Langmuir probe apparatus. Upper bounds of <10−8 cm3 s−1 were found for the reaction of C+ with Br− and I−, and a rate constant of 4.2 ± 1.1 × 10−9 cm3 s−1 was measured for the reaction with Cl−. The C+ + Cl− mutual neutralization reaction was studied theoretically from first principles, and a rate constant of 3.9 × 10−10 cm3 s−1, an order of magnitude smaller than experiment, was obtained with spin-orbit interactions included using a semiempirical model. The discrepancy between the measured and calculated rate constants could be explained by the fact that in the experiment, the total loss of C+ ions was measured, while the theoretical treatment did not include the associative ionization channel. The charge transfer was found to take place at small internuclear distances, and the spin-orbit interaction was found to have a minor effect on the rate constant. [ABSTRACT FROM AUTHOR]

Potential energy functions of the OH molecule are investigated from small to large inter-atomic distances R. The electronic problem is treated using an efficient Full Configuration Interaction (Full CI) approach that avoids orbital jumps found usually in multi-configuration self-consistent-field followed by multi-reference configuration interaction calculations of excited states. The calculations are performed for all the doublet, quartet, and sextet OH molecular states, up to the O(2p34s 3S) + H(1s 2S) asymptote, and for the lowest O− + H+ and O+ + H− ionic states. Inter-atomic distances, ranging from 0.5 Å to 20 Å, are spanned with a very small step in order to describe accurately the avoided crossings between the adiabatic potential energy functions. The accuracy of the potentials at small and large R values is analyzed. These Full CI calculations provide for the first time a global description of the 40 lowest molecular states of OH, well suited for dynamical calculations. The resulting potentials are used to obtain first estimates of cross sections and rate coefficients for different inelastic processes through the multichannel approach. This method, based on a Landau-Zener formalism taking into account the ionic-covalent avoided crossings at large distances, gives reliable results for the most intense transitions. It is shown that the largest rate coefficients correspond to mutual neutralization and ion-pair production processes. [ABSTRACT FROM AUTHOR]

The increasing number of proposed technologies for the active treatment of acid mine drainage (AMD) raises a problem for decision-makers during the selection process. Selecting the optimum treatment technology requires extensive analysis to determine the best possible treatment based on multiple and often conflicting criteria. The introduction of multi-decision criteria analysis (MCDA) provides a systematic approach to problem-solving based on both quantitative and qualitative data. In this study, analytic hierarchy process (AHP) as an MCDA tool was used to select the optimum treatment option for AMD in a local copper mining site in the Philippines. Three treatment technologies were found to be the most applicable - a combination of Conventional Lime Neutralization and Sulfidogenic Bioreactor (CLN + SB), High-Density Sludge (HDS) Process, and a combination of Two-Step Neutralization Ferrite Formation and Sulfidogenic Bioreactor (TSNFF + SB). Three criteria - technical, economic, and environmental - and eight sub-criteria were used to evaluate and analyze the three alternatives systematically. The overall ranking of the alternatives was TSNFF + SB > HDS > CLN + SB. However, sensitivity analysis showed that HDS was the most stable treatment technology when equal weights were given for each criterion. Implications from this study could provide a more reliable information for possible technology adoption to sustainably address problems on AMD which is one of the leading global environmental problems today. [ABSTRACT FROM AUTHOR]

Acid-alkaline electrolyzers utilize an acidic catholyte and alkaline anolyte, which lower the thermodynamic voltage requirement for water splitting. Experiments have demonstrated the feasibility of acid-alkaline electrolyzers with proton exchange membranes, but a mathematical model has yet to be developed to understand their operation. This work developed a multiphysics model of a batch acid-alkaline electrolyzer with a H2SO4 catholyte, a NaOH anolyte, and a proton exchange membrane. The model was formulated in COMSOL Multiphysics® and validated using experimental current vs. voltage data in literature. The electrolyzer's reactions and ion transport were analyzed based on the electrolyte potential, concentration profiles, and ion fluxes calculated by the model. The charge imbalance due to the consumption of H+ and OH- in the catholyte and anolyte, respectively, is addressed by Na+ transport from the anolyte to the catholyte. This contradicts the prevailing hypothesis that electroneutrality in a proton exchange membrane acid-alkaline electrolyzers is preserved by the Second Wien Effect, or water splitting in high electric fields. H+ is transported from the catholyte to the anolyte, which results in undesired acid-base neutralization. This is minimized by increasing the applied voltage, which shows a tradeoff between power and reactant consumption. Na+-selective membranes also hinder the neutralization reaction, but their realization is challenging due to the smaller Stokes radius of H+. The proposed model can be used to optimize the parameters of a batch electrolyzer and aid in the design of a continuous electrolyzer stack. [ABSTRACT FROM AUTHOR]

Energy‐saving hydrogen production can be achieved by using renewables or decoupling the sluggish oxygen evolution reaction from overall water splitting, which still needs electricity input. We have realized hydrogen production and water desalination with on‐demand electricity output via an electrochemical neutralization chemistry strategy that couples acidic hydrogen evolution and alkaline hydrazine oxidation with ionic exchange. The electrochemical neutralization cells allow efficient use of chemical energy and low‐grade heat from the surroundings to output 0.81 kWh electricity per m3 of hydrogen. Cell function can be rapidly switched to electricity output with a high peak power density up to 85.5 mW cm−2 or spontaneous hydrogen production at a high rate up to 70.1 mol h−1 m−2 without breaking cell operation or changing cell configuration. Fast water desalination is simultaneously achieved at a high salt removal rate of 56.1 mol h−1 m−2 without an external electricity supply. [ABSTRACT FROM AUTHOR]

The object of the study is the fruits of melon. The problem is the crop that remains in the fields. The article provides an overview of technologies for the processing of melons, and studies of the authors are given. On the basis of these studies, technological schemes for the production and formulation of such products as jam, jam, confiture, blended juices, vegetable oil from melon seeds were proposed and justified. Optimal additives and ways of introducing pectin into them are determined. The presence in finished products of vitamins of group B, vitamin C, ß-carotene, almost all essential amino acids, micro- and macroelements, the content of which does not noticeably decrease during storage under the optimal conditions established by us. Studies have been carried out on the selection of an extractant and the determination of the optimal parameters for extraction, isolation, neutralization and drying of pectin from melon peel. As a result, pectin was obtained with a degree of esterification of 67...69 %, a jelly-forming ability of more than 170 degrees of Tarr Baker, and a jelly strength of about 460 mm Hg. [ABSTRACT FROM AUTHOR]

Alkaline wastewater from tunnel construction can cause environmental problems when draining into water streams like rivers and lakes. Research interest in the neutralization of alkaline wastewater using CO 2 based on the carbon utilization concept has been increasing. In this study, the effects of key parameters such as the flow rate (FR) of CO 2 , initial water temperature (T), pH, and turbidity (TURB) on CO 2 neutralization of alkaline wastewater were investigated through laboratory experiments and field tests using alkaline wastewater collected from the Yunnan Dianzhong Water Diversion Engineering, China. Results revealed that 1.5 L min−1 was the optimal flow rate for CO 2 gas. The water pH (p < 0.001) and TURB (p < 0.001) significantly affected the neutralization performance of CO 2. The pH, TURB, electrical conductivity and total dissolved solids of alkaline wastewater can be effectively reduced by CO 2. The least time required for the treatment was noted at a T, pH, and TURB of 20 °C, 10.5, and 80 NTU, respectively. Laboratory and field stability experiments have shown CO 2 to be effective in reducing the pH of alkaline wastewater and consistently maintaining its pH within the discharge standard compliance range (6–9). A cost saving of $0.26 per 1 m3 of water was achieved comparing with neutralization of alkaline wastewater using citric acid. In summary, this study for the first time explored the efficiency and potential influencing factors for the treatment of alkaline tunnel construction wastewater using CO 2. It proves the effectiveness and economic benefits of the proposed technology. [Display omitted] • PH, turbidity, and CO 2 flow rate mainly affect CO 2 neutralization. • CO 2 neutralization reduces alkaline wastewater pH with good stability. • CO 2 neutralization is 92.86% less expensive compared with citric acid neutralization. • CO 2 neutralization enabled alkaline wastewater to meet the standard discharge (<9). [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Beta variant of concern (VOC) resists neutralization by major classes of antibodies from COVID-19 patients and vaccinated individuals. In this study, serum of Beta-infected patients revealed reduced cross-neutralization of wild-type virus. From these patients, we isolated Beta-specific and cross-reactive receptor-binding domain (RBD) antibodies. The Beta-specificity results from recruitment of VOC-specific clonotypes and accommodation of mutations present in Beta and Omicron into a major antibody class that is normally sensitive to these mutations. The Beta-elicited cross-reactive antibodies share genetic and structural features with wild type-elicited antibodies, including a public VH1-58 clonotype that targets the RBD ridge. These findings advance our understanding of the antibody response to SARS-CoV-2 shaped by antigenic drift, with implications for design of next-generation vaccines and therapeutics. [ABSTRACT FROM AUTHOR]

Much effort has been devoted to studying the absorption of anthropogenic CO2 by the surface and subsurface ocean, where surface seawater acidifies rapidly while the deep ocean was thought to respond to CO2 intrusion at longer time scales. However, recent studies have revealed rapid acidification of the deep Japan/East Sea, implying that ongoing changes in ocean dynamics are accelerating acidification at depth, and the controlling mechanisms have not been fully addressed. Using a multibox model of ocean circulation and carbonate chemistry, we demonstrate that a combination of reduced deep/bottom water formation and an increase in organic matter remineralization can best explain the observed pattern of rapid acidification in deep waters. In contrast, acidification in the intermediate layer is controlled by increased particulate organic carbon remineralization accompanied by intensified intermediate ventilation. Variations of ventilation and remineralization of particulate organic carbon dominating acidification in different layers of the water column need to be considered in future investigations. Plain Language Summary: Increased oceanic uptake of anthropogenic CO2 from the atmosphere has caused serious environmental problems, such as ocean acidification. Typically, the rapid acidification occurs in the surface and subsurface sea waters only because CO2 intrusion into the deep ocean takes more time. Recent investigations in the Japan/East Sea indicate that its deep water is acidifying at an unexpected rate, though the controlling mechanisms have not been fully understood. Thus, we built a multibox of ocean circulation and carbonate chemistry to investigate possible controls. Our results indicate that the acidification in different layers of the water column is controlled by different factors. The reduced deep/bottom water formation related to global warming resulted in the rapid deep acidification, while the rapid acidification of intermediate water is related to increased remineralization of particulate organic carbon, fueled by intensified intermediate ventilation. The neutralization by dissolution of sedimentary calcium carbonate in the Japan/East Sea is nearly negligible so that fast deep acidification can take place. Thus, the Japan/East Sea has distinct features other than acidification in other global oceans in which acidification can be partially buffered by the dissolution of previously deposited calcium carbonate. Key Points: Factors controlling acidification of different water masses in Japan/East Sea are investigated using a multibox modelReduced deep ventilation and increased intermediate ventilation and remineralization control acidification in these two contrasting layersThe sedimentary calcium carbonate is insignificant in neutralizing the rapid deep acidification in the Japan/East Sea [ABSTRACT FROM AUTHOR]

In this study, the duration of immunity as well as maternally derived antibodies (MDA) induced by the innovated tissue culture pigeon pox vaccine (TC-PPV) were evaluated for the first time. It was found that the postvaccinal reaction was more prominent in pigeons vaccinated with egg-adapted PPV (EG-PPV) (100%) than in pigeons vaccinated with TC-PPV (88%). The duration of induced immunity was higher using EG-PPV (1 year with a peak of neutralizing antibodies index 3.25 while it was 2.75 using TC-PPV) after 1 month of vaccination. MDA in squabs of vaccinated dams with TC-PPV maintained the protective level of antibodies up to 3weeks post-hatching (WPH) with 100% protection against a challenge. In contrast, in squabs of vaccinates with EGPPV, it remained up to 4 WPH with 90 % protection. Such antibody levels hinder the immune response to vaccination with TC-PPV resulting in vaccination failure with 40% protection for squabs of TC-PPV vaccinated dams at 3rd WPH and 60% protection for squabs of EG-PPV vaccinated dams at 4th WPH reflecting the successive vaccination at the 4th WPH and 5th WPH, respectively for hatched squabs with 80% protection in both groups while in squabs of unvaccinated dams; the vaccination with TC-PPV appears to be protective from 2nd WPH with 100% protection. In addition, this study recommends revaccination of pigeons with TC-PPV after 10 months and vaccination of their squabs not before 4 WPH to avoid vaccination failure by M DA. [ABSTRACT FROM AUTHOR]

The performance of nitrogen vacancy (NV-) based magnetic sensors strongly depends on the stability of nitrogen vacancy centers near the diamond surface. The sensitivity of magnetic field detection is diminished as the NV- turns into the neutralized charge state NV0. We investigate the neutralization of NV- and calculate the ratio of NV0 to total NV (NV-+NV0) caused by a hydrogen terminated diamond with a surface water layer. We find that NV- neutralization exhibits two distinct regions: near the surface, where the NV- is completely neutralized, and in the bulk, where the neutralization ratio is inversely proportional to depth following the electrostatic force law. In addition, small changes in concentration can lead to large differences in neutralization behavior. This phenomenon allows one to carefully control the concentration to decrease the NV- neutralization. The presence of nitrogen dopant greatly reduces NV- neutralization as the nitrogen ionizes in preference to NV- neutralization at the same depth. The water layer pH also affects neutralization. If the pH is very low due to cleaning agent residue, then we see a change in the band bending and the reduction of the two-dimensional hole gas region. Finally, we find that dissolved carbon dioxide resulting from direct contact with the atmosphere at room temperature hardly affects the NV- neutralization. [ABSTRACT FROM AUTHOR]

Mutual neutralization (MN) rate coefficients kMN for He+ with the anions Cl-, Br-, I-, and SF6 - are reported from 300 to 500 K. The measured rate coefficients may contain a contribution from transfer ionization, i.e., double ionization of the anion. The large rate coefficient for He+ + SF6 - (2.4 × 10-7 cm³ s-1 at 300 K) is consistent with earlier polyatomic MN results found to have a reduced mass dependence of µ-1/2. Neutralization of He+ by the atomic halides follows the trend observed earlier for Ne+, Ar+, Kr+, and Xe+ neutralized by atomic halides, kMN (Cl-) < kMN (Br-) < kMN (I-). Only an upper limit could be measured for the neutralization of He+ by Cl-. Predictions of the rate coefficients from a previously proposed simple model of atomic-atomic MN results are consistent with the present He+-halide rate coefficients. The temperature dependences are modestly negative for Br- and I-, while that for SF6- is small or negligible. [ABSTRACT FROM AUTHOR]

Mutual neutralization (MN) rate coefficients kMN for He+ with the anions Cl-, Br-, I-, and SF6 - are reported from 300 to 500 K. The measured rate coefficients may contain a contribution from transfer ionization, i.e., double ionization of the anion. The large rate coefficient for He+ + SF6 - (2.4 × 10-7 cm³ s-1 at 300 K) is consistent with earlier polyatomic MN results found to have a reduced mass dependence of µ-1/2. Neutralization of He+ by the atomic halides follows the trend observed earlier for Ne+, Ar+, Kr+, and Xe+ neutralized by atomic halides, kMN (Cl-) < kMN (Br-) < kMN (I-). Only an upper limit could be measured for the neutralization of He+ by Cl-. Predictions of the rate coefficients from a previously proposed simple model of atomic-atomic MN results are consistent with the present He+-halide rate coefficients. The temperature dependences are modestly negative for Br- and I-, while that for SF6- is small or negligible. [ABSTRACT FROM AUTHOR]

The work comprises researches on studying the possibility to use Fluoro-Anhydrite - fluor-hydric acid production waste in building industry. The effect of the dispersion and the amount of the neutralising agent on the completeness of the neutralisation reaction of acid Fluoro-Anhydrite is investigated. A method for obtaining a synthanite from hydrofluoric acid production waste is proposed, including neutralisation of the waste with a lime-containing component, followed by grinding and separation of the binder, characterized in that the production waste is additionally denaturalised by its chemical activation with quicklime to pH 12 and a sulfate additive, followed by grinding to a specific surface area of 9,000 cm² /g. Ensuring that the pH level of the binder mixture reaches 10-12 leads to an improvement in the physical and technical properties of synthanite: an increase in strength by 3.5-4 times, a reduction in the setting time by up to 9-12 times. The possibility has been proved to produce М25 and М50 dry plasters intended for finishing work based on developed airhardening synthanite. It is recommended to use plasters inside the premises when air humidity is not higher than (60-70) %. [ABSTRACT FROM AUTHOR]

Dissociative recombination (DR) rate coefficients for the naphthalene cation, C10H8+, and WF5+, and mutual neutralization (MN) rate coefficients for these species and five CnFm+ ions, were determined at 300 K using variable electron and neutral density attachment mass spectrometry (VENDAMS). DR proceeds at 9 ± 3 × 10-7 cm³ s-1 for C10H8+ and at 6.1 ± 1.4 × 10-7 cm³ s-1 for WF5+. Consistent with previous results, MN for the polyatomic cations with the halide anions Cl-, Br-, and I- exhibits an approximate μ-1/2 reduced mass dependence of the reactant partners, demonstrating that ion collision velocities influence the rate coefficients. This work is an extension of VENDAMS to systems, where low reactant concentrations are necessary to avoid significant reaction of product ions with the neutral precursor, i.e., conditions not suitable for traditional flowing afterglow measurements, as well as to ions of masses > - 100 Da, which are not amenable to the study of DR in magnetic storage rings. Our results expand the sparse literature on DR and MN of heavier ions. [ABSTRACT FROM AUTHOR]

Dissociative recombination (DR) rate coefficients for the naphthalene cation, C10H8+, and WF5+, and mutual neutralization (MN) rate coefficients for these species and five CnFm+ ions, were determined at 300 K using variable electron and neutral density attachment mass spectrometry (VENDAMS). DR proceeds at 9 ± 3 × 10-7 cm³ s-1 for C10H8+ and at 6.1 ± 1.4 × 10-7 cm³ s-1 for WF5+. Consistent with previous results, MN for the polyatomic cations with the halide anions Cl-, Br-, and I- exhibits an approximate μ-1/2 reduced mass dependence of the reactant partners, demonstrating that ion collision velocities influence the rate coefficients. This work is an extension of VENDAMS to systems, where low reactant concentrations are necessary to avoid significant reaction of product ions with the neutral precursor, i.e., conditions not suitable for traditional flowing afterglow measurements, as well as to ions of masses > - 100 Da, which are not amenable to the study of DR in magnetic storage rings. Our results expand the sparse literature on DR and MN of heavier ions. [ABSTRACT FROM AUTHOR]

Soil acidification through acid rain/deposition has been a serious problem that adversely affects the soil environment. In this study, Myxococcus xanthus, myxobacteria, was assessed towards neutralization of artificial acidic soil. Differences in initial pH and peat moss content in soil with incubated M. xanthus were being compared using a one-variable-at-a-time approach. It showed that the M. xanthus could neutralize the acidified soil using their specific metabolism, producing ammonium ions and hydroxide simultaneously. Increasing peat moss content could direct the neutralization performance of M. xanthus towards inhibition whereas reducing the peat moss content could improve the neutralization performance. Among experimental parameters such as initial pH, peat moss content in soil, and microorganism concentration, the interaction of soil amount either with peat moss content or microbial population density was meaningfully correlated to the neutralization of acidic soil. [ABSTRACT FROM AUTHOR]

Emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have raised concerns about resistance to neutralizing antibodies elicited by previous infection or vaccination. We examined whether sera from recovered and naïve donors, collected before and after immunizations with existing messenger RNA (mRNA) vaccines, could neutralize the Wuhan-Hu-1 and B.1.351 variants. Prevaccination sera from recovered donors neutralized Wuhan-Hu-1 and sporadically neutralized B.1.351, but a single immunization boosted neutralizing titers against all variants and SARS-CoV-1 by up to 1000-fold. Neutralization was a result of antibodies targeting the receptor binding domain and was not boosted by a second immunization. Immunization of naïve donors also elicited cross-neutralizing responses but at lower titers. Our study highlights the importance of vaccinating both uninfected and previously infected persons to elicit cross-variant neutralizing antibodies. [ABSTRACT FROM AUTHOR]

Precipitation processes have been successfully proved to be a feasible route to extract high-value products from wastes. However, reactive crystallization is characterized by fast kinetics, especially when highly concentrated solutions are used or sparingly soluble compounds precipitate, thus requiring a fast mixing of the reactants. In this context, T-shaped mixers have been extensively investigated both experimentally and numerically as a mean to achieve a rapid reactants homogenization. Many research efforts have been focused on the analysis of rectangular cross-sectional T-shaped mixers, while less attention has been devoted to the study of circular cross-sectional ones. In the present work, mixing times in a 3 mm circular crosssectional T-shaped mixer have been optically estimated by exploiting the extremely fast neutralization reaction between sodium hydroxide and hydrochloric acid solutions. Reynolds numbers ranging between 1,000 and 6,000 were investigated. Mixing phenomena were (i) captured by detecting the colour change of a pH indicator by means of a high frame rate camera and (ii) quantified by a suitable image analysis technique. The assessed mixing times were found in accordance with available data in the literature. [ABSTRACT FROM AUTHOR]

The beat in physical systems is a transparent and well-understood phenomenon. It may occur in forced oscillatory systems and as a result of the interference of two waves of slightly different frequencies. However, in chemical systems, the realization of the latter type of the beat phenomenon has been lacking. Here we show that a periodic titration of acid and alkaline solutions with each other using programmable syringe pumps in a continuous stirred-tank reactor exhibits the beat phenomenon in the temporal pH oscillation pattern if the time periods of sinusoidal inflow rates of the reagents are slightly different. Interestingly, the frequency of the chemical beat pattern follows the well-known relationship from physics, namely the frequency of the beat is equal to the absolute value of the difference of the two wave frequencies. Based on our strategy, we can design and engineer non-autonomous pH oscillatory systems, in which the characteristics of the temporal oscillations (amplitude, time period) can easily and precisely be controlled by the experimental conditions such as the inflow rates and feed concentrations. The demonstrated phenomena can be exploited in practical applications, we use the non-autonomous pH oscillators to drive the reversible assembly and disassembly of pH-sensitive building blocks (oleic acid and gold nanoparticles), both highly relevant in nanotechnology and biomedical applications. [ABSTRACT FROM AUTHOR]

Approaches are needed for therapy of the severe acute respiratory syndrome from SARS-CoV-2 coronavirus (COVID-19). Interfering with the interaction of viral antigens with the angiotensin converting enzyme 2 (ACE-2) receptor is a promising strategy by blocking the infection of the coronaviruses into human cells. We have implemented a novel protein engineering technology to produce a super-potent tetravalent form of ACE2, coupled to the human immunoglobulin γ1 Fc region, using a self-assembling, tetramerization domain from p53 protein. This high molecular weight Quad protein (ACE2-Fc-TD) retains binding to the SARS-CoV-2 receptor binding spike protein and can form a complex with the spike protein plus anti-viral antibodies. The ACE2-Fc-TD acts as a powerful decoy protein that out-performs soluble monomeric and dimeric ACE2 proteins and blocks both SARS-CoV-2 pseudovirus and SARS-CoV-2 virus infection with greatly enhanced efficacy. The ACE2 tetrameric protein complex promise to be important for development as decoy therapeutic proteins against COVID-19. In contrast to monoclonal antibodies, ACE2 decoy is unlikely to be affected by mutations in SARS-CoV-2 that are beginning to appear in variant forms. In addition, ACE2 multimeric proteins will be available as therapeutic proteins should new coronaviruses appear in the future because these are likely to interact with ACE2 receptor. [ABSTRACT FROM AUTHOR]

The spontaneous and photo-induced neutralization of C7- produced in a laser ablation source was measured in an electrostatic storage ring. The measurements provide three independent determinations of the radiative cooling of the ions, based on the short time spontaneous decay and on the integrated amplitude and the shape of the photo-induced neutralization signal. The amplitude of the photo-induced signal was measured between 0.5 ms and 35 ms and found to depend on photon wavelength and ion storage time. All three signals can be reproduced with identical thermal IR radiative cooling rates with oscillator strengths equal to theoretical predictions. In addition, the measurements provide the excitation energy distribution. [ABSTRACT FROM AUTHOR]

The spontaneous and photo-induced neutralization of C7- produced in a laser ablation source was measured in an electrostatic storage ring. The measurements provide three independent determinations of the radiative cooling of the ions, based on the short time spontaneous decay and on the integrated amplitude and the shape of the photo-induced neutralization signal. The amplitude of the photo-induced signal was measured between 0.5 ms and 35 ms and found to depend on photon wavelength and ion storage time. All three signals can be reproduced with identical thermal IR radiative cooling rates with oscillator strengths equal to theoretical predictions. In addition, the measurements provide the excitation energy distribution. [ABSTRACT FROM AUTHOR]

The fast and untraceable virus mutations take lives of thousands of people before the immune system can produce the inhibitory antibody. The recent outbreak of COVID-19 infected and killed thousands of people in the world. Rapid methods in finding peptides or antibody sequences that can inhibit the viral epitopes of SARS-CoV-2 will save the life of thousands. To predict neutralizing antibodies for SARS-CoV-2 in a high-throughput manner, in this paper, we use different machine learning (ML) model to predict the possible inhibitory synthetic antibodies for SARS-CoV-2. We collected 1933 virus-antibody sequences and their clinical patient neutralization response and trained an ML model to predict the antibody response. Using graph featurization with variety of ML methods, like XGBoost, Random Forest, Multilayered Perceptron, Support Vector Machine and Logistic Regression, we screened thousands of hypothetical antibody sequences and found nine stable antibodies that potentially inhibit SARS-CoV-2. We combined bioinformatics, structural biology, and Molecular Dynamics (MD) simulations to verify the stability of the candidate antibodies that can inhibit SARS-CoV-2. [ABSTRACT FROM AUTHOR]

An experimental investigation of chemically triggered convection is carried out. A two-layer system of miscible reactive fluids—the neutralization reaction between an acid and a base—is considered in a vertical Hele-Shaw cell. This system is subject to the action of gravity and vertical translational vibrations (modulated gravity). During the reaction, a less dense salt solution emerges in the reaction zone, thus triggering the buoyancy-driven convection in the form of concentration plumes rising in the upper layer. The particle image velocimetry is used as the method of study. The considered system is non-stationary, and a technique is developed for the processing of a long series of images registered during experiments. The evolution of the flow structures and of the convection intensity is analyzed. In the considered range of experimental parameters the vibrations slightly slow down the convection. [ABSTRACT FROM AUTHOR]

In order to reduce the price of dairy products and exclude environmental damage caused by improper utilization of whey, it is necessary to ensure its 100% processing by applying advanced innovative technology. Acid whey processing is the biggest problem in the production of lactose by applying the existing technology. Therefore such whey requires further processing. First and foremost, it is necessary to provide partial demineralization and reduction of acidity. In modern conditions, the reduction of acidity in dairy enterprises is carried out by adding of an alkaline reagent. The introduction of alkali affects the quality of the product. Electrodialysis using bipolar membranes can be applied as an alternative to alkaline treatment of milk whey. Innovative technology is a combination of classic and bipolar electrodialysis. Acid whey demineralization and acidity correction will be performed without the use of additional reagents. In order to reduce the buffer volume (4 times), partially demineralize whey and reduce its acidity (up to 30%), the milk whey is nanofiltered before electrodialysis. [ABSTRACT FROM AUTHOR]

Nature friendly technologies in today's world are the subject of scientific research and the interest of local authorities and the residents themselves. In the context of the city, one of the most important issues is the neutralization of air pollution generated by transport and heating of the premises with the use of solid fuels. The article analyses differences of the response of traditional and photocatalytic paving stones. We analysed water absorption, frost resistance, tensile strength at splitting and abrasion of paving stones. It has been proved that paving stones exposed to atmospheric factors and pollution during one heating season met the assumed quality criteria. In addition, the results obtained for the characteristics analysed were higher than the results of samples tested in laboratory conditions. The results also indicate a slight advantage of photocatalytic cubes in terms of their resistance to abrasion and tensile strength at splitting. Traditional and photocatalytic paving stones withstand well the operating conditions. It seems that products based on TioCem® cement are the future implementation of pedestrian and traffic routes. [ABSTRACT FROM AUTHOR]

We have studied the dependence of several ion-ion mutual neutralization (MN) reactions on helium density in the range from 1.6 × 1016 to 1.5 × 1017 cm-3 at 300 K, using the Variable Electron and Neutral Density Attachment Mass Spectrometry method. The rate coefficients of the reactions Ar+ + Br2-, Ar+ + SF6-, and Ar+ + C7F14- were found to be independent of gas density over the range studied, in disagreement with earlier observations that similar MN reactions are strongly enhanced at the same gas densities. The cause of the previous enhancement with density is traced to the use of 'orbital-motion-limit' theory to infer ion densities from the currents collected by ion-attracting Langmuir probes in a region where it is not applicable. [ABSTRACT FROM AUTHOR]

The specific focus of this study was on the effects of flocculation duration, intensity, and scheme (i.e., single or multistage) on floc formation (time and size) and treated turbidity (settled and filtered). The results showed that floc formation times were 2–8 times longer under charge neutralization conditions compared with sweep flocculation conditions for the low‐turbidity and low‐organics water studied. Settled turbidity removals were dependent on the applied mixing conditions. Filtered turbidity was found to be independent of the investigated flocculation conditions, which calls into question the true value of mixing conditions with substantial implications on facility design, operation, and regulation. While at least 9 min of flocculation time was necessary under some coagulation conditions, the intensity and scheme of flocculation were not critical to overall treatment efficiency under the studied conditions. These findings might offer potential savings to water utilities in terms of design, construction, operation, and maintenance costs. [ABSTRACT FROM AUTHOR]

Keywords: biotin; immunoassay; interference; patient safety; streptavidin EN biotin immunoassay interference patient safety streptavidin e130 e133 4 07/13/20 20200801 NES 200801 To the Editor, Biotin interference has become a matter of concern with immunoassays because of the risk of erroneous results leading to harmful clinical consequences [[1]], [[2]], [[3]], [[4]], [[5]]. Blood sampling was performed prior to biotin intake, 1.5 h after the biotin intake (corresponding to the C SB max sb of 100 mg biotin [[3]]), and 24 h after the biotin intake. When biotin is absent in the serum sample, unbound biotin binding protein-dye conjugate binds to the biotin derivative immobilized on the membrane, producing a saturated rose-pink color band in the test zone. Conversely, when the biotin level is at or above 15 ng/mL, free biotin competes with the immobilized biotin derivative on the membrane by binding to the biotin binding protein-dye conjugate, forming a biotin-biotin binding protein-dye complex, preventing the development of a rose-pink color band. [Extracted from the article]

Keywords: biotin; immunoassay; interference; patient safety; streptavidin EN biotin immunoassay interference patient safety streptavidin e130 e133 4 07/13/20 20200801 NES 200801 To the Editor, Biotin interference has become a matter of concern with immunoassays because of the risk of erroneous results leading to harmful clinical consequences [[1]], [[2]], [[3]], [[4]], [[5]]. Blood sampling was performed prior to biotin intake, 1.5 h after the biotin intake (corresponding to the C SB max sb of 100 mg biotin [[3]]), and 24 h after the biotin intake. When biotin is absent in the serum sample, unbound biotin binding protein-dye conjugate binds to the biotin derivative immobilized on the membrane, producing a saturated rose-pink color band in the test zone. Conversely, when the biotin level is at or above 15 ng/mL, free biotin competes with the immobilized biotin derivative on the membrane by binding to the biotin binding protein-dye conjugate, forming a biotin-biotin binding protein-dye complex, preventing the development of a rose-pink color band. [Extracted from the article]

Acid–base copolymer materials are of considerable interest because of their fundamental implications for acid–base bifunctional catalysis applications. However, quenching the acid and base sites of the copolymer with each other in free radical polymerizations is still challenging. Herein, we demonstrate that the polymerization of styrenesulfonic acid-co-4-vinylpyridine into the mesoporous carbon material (i.e., CMK-3) can control the chain growth polymerization and result in decreasing the interaction of the acid–base sites. The results showed that by using CMK-3, 40% of the acid and base sites of the copolymer remain in their original form while 60% of acid and base sites convert to the pyridinium and sulfonate forms. Furthermore, it is demonstrated that this material can be processed as a heterogeneous bifunctional acid–base catalyst in the tandem one-pot acid–base reaction (i.e., deacetalization–Knoevenagel condensation reaction) with a high catalytic activity in aqueous media. [ABSTRACT FROM AUTHOR]

Bovine pancreatic trypsin inhibitor (BPTI) is a well‐studied model for investigation of protein folding and stability. Here, we report the synthesis and characterization of wild‐type BPTI and a diastereomeric protein analogue [Gly37D‐Ala]BPTI. Each 58‐residue polypeptide chain was made by native chemical ligation of two peptide segments, BPTI[1‐29]‐αthioester and the appropriate version of the Cys30‐58 BPTI peptide segment. Boc chemistry in situ neutralization solid phase synthesis was used to prepare the peptide segment reactants. The resulting full‐length polypeptide chains were folded in a cysteine/cystine redox buffer to give synthetic protein molecules containing three disulfide bonds. The diastereomeric analogue [Gly37D‐Ala]BPTI folded as efficiently as the native protein. Synthetic proteins were characterized by analytical LCMS and by natural‐abundance 1H‐15N HSQC NMR fingerprinting. These results illustrate the power of Boc chemistry peptide synthesis and its utility for the total chemical synthesis of protein molecules. [ABSTRACT FROM AUTHOR]

A discharge plasma simulation based on a three-fluid model is generally utilized to understand the physical mechanism in a dielectric barrier discharge (DBD) plasma actuator. In this study, the influence of chemical reactions considered in a numerical model on the simulation results is investigated from the viewpoint of electrohydrodynamic (EHD) force generation in the DBD plasma actuator. Positive and negative streamers are simulated utilizing three types of models considering different reactions and species, and the investigation is conducted in two steps. In the first step, where the influence of the neutralization process is investigated, the electron recombination with a cluster ion (O4+) plays an important role; it contributes to the decrease in seed electron production and effective coefficient of ionization for the positive streamer, and the decrease in negative ion production for the negative streamer; as a result, the propagation length and EHD force generation decrease. In the second step, where the influence of the production process is investigated, the stepwise ionization from metastable states has little influence owing to quite low production rates. Therefore, the simulation results indicate that the numerical model needs to consider the electron recombination with O4+ to accurately predict the streamer propagation and EHD force generation, while it is unnecessary to take into account the metastable molecules. [ABSTRACT FROM AUTHOR]

Recently, the selective removal of H2S and CO2 has been highly desired in natural gas sweetening. Herein, four novel azole‐based protic ionic liquids (PILs) were designed and prepared through one‐step neutralization reaction. The solubility of H2S (0–1.0 bar), CO2 (0–1.0 bar), and CH4 (0–5.0 bar) was systematically measured at temperatures from 298.2 to 333.2 K. NMR and theoretical calculation were used to investigate the reaction mechanism between these PILs and H2S. Reaction equilibrium thermodynamic model (RETM) was screened to correlate the H2S solubility. Impressively, 1,5‐diazabicyclo[4,3,0] non‐5‐ene 1,2,4‐1H‐imidazolide ([DBNH][1,2,4‐triaz]) shows the highest H2S solubility (1.4 mol/mol or 7.3 mol/kg at 298.2 K and 1.0 bar) and superior H2S/CH4 (831) and CO2/CH4 (199) selectivities compared with literature results. Considering the excellent absorption capacity of H2S, high H2S/CH4, and CO2/CH4 selectivity, acceptable reversibility, as well as facile preparation process, it is believed that azole‐based PILs provide an attractive alternative in natural gas upgrading process. [ABSTRACT FROM AUTHOR]

Background: Infection of burn wounds by multidrug-resistant (MDR) Pseudomonas aeruginosa (P. aeruginosa) is a leading cause of morbidity and mortality and remains one of the most challenging concerns for the burns unit. The aim of this study is purify and characterize the haemolysin produced by multidrug resistant P. aeruginosa PAO1 isolated from burn wounds. Methods: Isolation and identification of P. aeruginosa from burns was done by standard bacteriological methods. P. aeruginosa PAO1 was identified by PCR amplification and sequencing of the 16S rRNA gene. The haemolysin of P. aeruginosa PAO1 was purified by 70% ammonium sulphate precipitation followed by gel filtration on Sephadex G-100, and separation by SDS-Poly Acrylamide Gel Electrophoresis. In vivo toxicity of the purified haemolysin was determined by intraperitoneal injection of Swiss albino mice, and in vitro toxinantitoxin neutralization test was performed as previously described. Results: The pure haemolysin had a molecular weight of 37 kDa, with maximum activity at 25°C for 30 minutes and stable within pH range of 4-9 (maximum activity at pH 7). The haemolysin was activated by Ca2+, Fe3+ and Cu2+. Intraperitoneal injection of mice with 0.5ml of haemolysin (128 HU/ml) caused 100% mortality while 0.5 and 0.1 ml of haemolytic titer (64 HU/ml) of the heated haemolysin (toxoid) caused 50% and 0% mortality respectively. In vitro toxin-antitoxin neutralization test revealed that anti-haemolysin antitoxin was present in the serum of the mice that were previously vaccinated with heated toxin. Conclusion: This study concluded that haemolysin can be a potential vaccine component for prevention of haemolysis caused by multidrug resistant P. aeruginosa in burn patients. [ABSTRACT FROM AUTHOR]

The electrical neutralization ability of polyaluminum chlorides (PACls) with respect to humic acid was investigated by the fluorescence quenching method. The Stern-Volmer constant (Kq) at various pH and coagulation doses was determined for polyaluminum chlorides (PACl-B) of various basicities (B, B = [OH-]/[Al]). The experimental results show that under acidic conditions, the order of Kq values of PACl-B is PACl-2.5 > PACl-2.3 > PACl-1.5 > AlCl3. In solutions of pH = 7, the order of Kq values is PACl-1.5 > PACl-2.3 > PACl-2.5 > AlCl3. When pH > 7, aluminum ions are rapidly hydrolyzed, thus PACls of various basicities generally do not show capacity for electrical neutralization with humic acid. At pH = 6, all PACls-B obtain the maximum Kq values, indicating that humic acid and PACl-B coagulation process is less affected by H+ or OH- ions, and produces the best electrical neutralization ability. Compared to the past method of using surface potential as a means of determining the ability of neutralization of coagulation, the results of this study show that the Kq value of the quenching effect can reduce the experiment complexity. [ABSTRACT FROM AUTHOR]

The 2,5-dihydroxyterephthalic acid (H4-p-DHT) is of special interest in the field of materials science because of the two symmetric sets of oxygen donor functional groups (i.e., β-hydroxy acid moieties). In its partially (–2H) or totally (–4H) deprotonated form, it is an efficient organic ligand making the synthesis of numerous coordination polymers possible. In addition, it exhibits dual redox-active properties, which make it very interesting as electrode material when combined with alkali and alkaline-earth elements. Herein, we report on a specific study on alkali salts obtained from partial to complete neutralization of 2,5-dihydroxyterephthalic acid in the Li–Na system, which notably enable us to prepare the mixed phase Na2(Li2)-p-DHT (Na2Li2C8H2O6) and to test it electrochemically vs. Li. Depending on the experimental conditions, two Li-polymorphs and one Na compound, containing H2-p-DHT2− ligands with deprotonated carboxylic groups, were obtained, namely, M2(H2)-p-DHT(H2O)4 M = Li (1, 2) and Na (3) as well as the first mixed alkali metal compound, i.e. Na2(Li2)-p-DHT(H2O)8 (4). The single crystal structure analyses showed that all compounds display various inorganic motifs with discrete LiO4 tetrahedra (1, 2), Li2O6 dimers of edge-sharing LiO4 tetrahedra (2), 1∞ [NaO4]−7 1-D chains of edge-sharing NaO6 octahedra (3) and [Li2Na2O14]24− clusters of LiO4 tetrahedra and NaO6 octahedra (4). The electrochemical assessment of the anhydrous Na2(Li2)-p-DHT compound measured in Li half-cell revealed however poor performances compared to Li4-p-DHT (Li4C8H2O6) due to cationic disorder of the two alkali ions in the crystal structure giving rise to the progressive conversion of the pristine phase to Li4-p-DHT upon cycling. [ABSTRACT FROM AUTHOR]

Na2SO4·10H2O is a promising phase change material for energy saving buildings. In order to suppress the phase segregation and diminish the super-cooling degree of Na2SO4·10H2O, PAA/Na2SO4·10H2O phase change composites were prepared through absorbing the molten sodium sulfate decahydrate (Na2SO4·10H2O) into the sodium polyacrylate (PAA) matrix. The polymerization condition of PAA was optimized to obtain maximal absorption of Na2SO4·10H2O. The optimal condition was: N, N-methylenebisacrylamide (Bis, as crosslinking agent) mass fraction of 0.02%, ammonium persulfate (APS, as initiator) mass fraction of 0.1%, neutralization degree of 75%, acrylic acid (AA, as monomer) mass fraction of 30%, polymerization temperature of 70 °C, and reaction time of 3 h. The morphology and microstructure, phase changing behavior, thermal stability and thermal cycling stability of the phase change composites were investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TG), polarized optical microscope (POM) and scanning electron microscope (SEM). Results showed that the absorption amount of Na2SO4·10H2O in the PAA matrix could be as much as 93%. The threedimensional network structure effectively inhibited the phase segregation of Na2SO4·10H2O and formed stable phase change composites. Moreover, the phase change composites had high latent heat, exhibiting good thermal stability and cycling stability, and the phase change temperature and enthalpy maintained nearly unchanged after 45 heating-cooling cycles. The supercooling degree of PAA/ Na2SO4·10H2O was further decreased by adding borax. When m(Borax): m(Na2SO4· 10H2O)=5%, the supercooling degree of the phase change composites could be decreased to 1.0 °C. Furthermore, no leakage was observed during the heating procedure even when Na2SO4·10H2O was melted. [ABSTRACT FROM AUTHOR]