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This study presents a reproducible and scalable method for synthesizing silica nanoparticles (SNPs) with controlled sizes below 200 nm, achieved by systematically varying three key reaction parameters: ammonium hydroxide concentration, water concentration, and temperature. SNPs with high monodispersity and controlled dimensions were produced by optimizing these factors. The results indicated a direct correlation between ammonium hydroxide concentration and particle size, while higher temperatures resulted in smaller particles with increased polydispersity. Water concentration also influenced particle size, with a quadratic relationship observed. This method provides a robust approach for tailoring SNP sizes, with significant implications for biomedical applications, particularly in drug delivery and diagnostics. Using eco-friendly solvents such as ethanol further enhances the sustainability and cost-effectiveness of the process. [ABSTRACT FROM AUTHOR]

This study presents a reproducible and scalable method for synthesizing silica nanoparticles (SNPs) with controlled sizes below 200 nm, achieved by systematically varying three key reaction parameters: ammonium hydroxide concentration, water concentration, and temperature. SNPs with high monodispersity and controlled dimensions were produced by optimizing these factors. The results indicated a direct correlation between ammonium hydroxide concentration and particle size, while higher temperatures resulted in smaller particles with increased polydispersity. Water concentration also influenced particle size, with a quadratic relationship observed. This method provides a robust approach for tailoring SNP sizes, with significant implications for biomedical applications, particularly in drug delivery and diagnostics. Using eco-friendly solvents such as ethanol further enhances the sustainability and cost-effectiveness of the process.

Large shiitake mushrooms (Lentinula edodes , pileus > 8 cm in diameter) are difficult to cultivate and account for only 3-5% of the total harvest. This study focused on the water absorption process within a log during the growth of fruiting bodies in order to increase the yield of large shiitake mushrooms. Konara oak logs (Quercus serrata, 85-95 mm in diameter, 290 mm in length) were inoculated with shiitake mycelium plugs and nine months later, young fruiting bodies developed, at which point the log was analyzed using magnetic resonance imaging (MRI) over a period of two weeks. The signal intensity and T 1 and T 2 relaxation time constants were determined from the acquired images, along with the distribution of water concentration within the entire log. The axial distributions of water concentrations in the log were higher in the 80 mm region around the fruiting body. The rate of decrease in water concentration indicated that water was supplied to the fruiting body from 80 mm axially in the upper half of the sapwood in the log. On the other hand, the water concentration in the heartwood did not decrease and the heartwood did not contribute to the water supply to the fruiting bodies. • Shiitake mycelium-inoculated log was measured by MRI over a two-week period. • Water was supplied to growing fruiting bodies from the sapwood section of the log. • The region supplying water to the fruiting body was on the upper part of the log. • The area of highest water concentration depended on the position of the fruiting body. [ABSTRACT FROM AUTHOR]

Evaluating the similarity between two entities such as primary and suspected metastatic lesions using quantitative dual-energy computed tomography (DECT) numbers may be useful. However, the criteria for the similarity between two entities based on DECT numbers remain unclear. We therefore considered the possibility that a similarity in DECT numbers within the same organ could provide suitable standards. Thus, we assumed that the variation in DECT numbers within a single organ is sufficiently minimal to be considered clinically equivalent. Therefore, the purpose of this preliminary study is to investigate the differences in DECT numbers within upper abdominal organs. This retrospective study included 30 patients with data from hepatic protocol DECT scans. DECT numbers of the following parameters were collected: (a, b) 70 and 40 keV CT values, (c) slope, (d) effective Z, and (e, f) iodine and water concentration. The agreement of DECT numbers obtained from two regions of interest in the same organ (liver, spleen, and kidney) were assessed using Bland–Altman analysis. The diagnostic ability of each DECT parameter to distinguish between the same or different organs was also assessed using receiver operating characteristic analysis. The 95% limits of agreement within the same organ exhibited the narrowest value range on delayed phase (DP) CT [(c) −11.2–8.3%, (d) −2.0–1.5%, (e) −11.3–8.4%, and (f) −0.59–0.62%]. The diagnostic ability was notably high when using differences in DECT numbers on portal venous (PVP) and DP images (the area under the curve of DP: 0.987–0.999 in (c)–(f)). Using the variability in DECT numbers in the same organ as a criterion for defining similarity may be helpful in making a differential diagnosis by comparing the DECT numbers of two entities.

Proper management, monitory and pollution controls measure should be maintained, for limited water resources, so as to reduce human health risks. Lead pollution can negatively affect human health. This study reviewed concentrations of lead in water and sediments of water bodies in Kenya, from samples or publications conducted between 1990 and 2021. Information on quantitative concentration values, locality, allowable standards, general methodology and possible pollutant sources for lead pollution in water and sediment were gathered. Based on the review, 71 concentration values (23.94%) for water, where above or similar to the Republic of Kenya (2006), maximum allowable value, with higher pollution levels in Kenya’s major urban areas. The 43 sedimentary concentrations, were in the range of 198.7 mg/kg to 5.9 mg/kg. Lead concentration varied with weather patterns, in some reviews. Lead and heavy metals pollution was mainly attributed to human, industrial or agricultural activities and poor waste management. There was variation in method used by different studies. More experimental researches and modeling techniques, should be considered, for accurate methodologies, within Kenya’s context. There should be proper treatment and monitoring of effluent, also human and industrial activities should be avoided near water body’s banks through enforcement of riparian areas protection.

Human blood is made up primarily of water. Water is significantly involved in balancing the human body. It affects the component of blood like mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and mean platelets volume (MPV). The water concentration varies from 80 to 90% in blood. The change in water concentration changes the refractive index of plasma, and the change in the refractive index of plasma also changes the refractive index of blood. The proposed structure is designed to analyze the water concentration in human blood by analyzing the shifting in resonant peak and this shifting is processed by machine learning algorithm to estimate the concentration of water in human blood. Nanocavity ring structures in the waveguide region are designed as sensing nodes in this proposed structure. The air hole radius of these Nanocavity ring structures is 80 and 50 nm, whereas the proposed structure's dimension is 12.15 by 8.45 μm2. The sensitivity of the design structure is 570 nm/RIU, and the quality factor is 650. The structure is simulated through the Finite Difference Time Domain (FDTD) method. [ABSTRACT FROM AUTHOR]

Evaluating the similarity between two entities such as primary and suspected metastatic lesions using quantitative dual-energy computed tomography (DECT) numbers may be useful. However, the criteria for the similarity between two entities based on DECT numbers remain unclear. We therefore considered the possibility that a similarity in DECT numbers within the same organ could provide suitable standards. Thus, we assumed that the variation in DECT numbers within a single organ is sufficiently minimal to be considered clinically equivalent. Therefore, the purpose of this preliminary study is to investigate the differences in DECT numbers within upper abdominal organs. This retrospective study included 30 patients with data from hepatic protocol DECT scans. DECT numbers of the following parameters were collected: (a, b) 70 and 40 keV CT values, (c) slope, (d) effective Z, and (e, f) iodine and water concentration. The agreement of DECT numbers obtained from two regions of interest in the same organ (liver, spleen, and kidney) were assessed using Bland–Altman analysis. The diagnostic ability of each DECT parameter to distinguish between the same or different organs was also assessed using receiver operating characteristic analysis. The 95% limits of agreement within the same organ exhibited the narrowest value range on delayed phase (DP) CT [(c) −11.2–8.3%, (d) −2.0–1.5%, (e) −11.3–8.4%, and (f) −0.59–0.62%]. The diagnostic ability was notably high when using differences in DECT numbers on portal venous (PVP) and DP images (the area under the curve of DP: 0.987–0.999 in (c)–(f)). Using the variability in DECT numbers in the same organ as a criterion for defining similarity may be helpful in making a differential diagnosis by comparing the DECT numbers of two entities. [ABSTRACT FROM AUTHOR]

Radial variation in water concentration from outer to inner lamellae is one of the characteristic features of annulus fibrosus (AF). In addition, water concentration changes are also associated with intervertebral disc (IVD) degeneration. Such changes alter the chemo-mechanical interactions among the biomolecular constituents at molecular level, affecting the load-bearing nature of IVD. This study investigates mechanistic impacts of water concentration on the collagen type I microfibrils in AF using molecular dynamics simulations. Results show, in axial tension, that increase in water concentration (WC) from 0% to 50% increases the elastic modulus from 2.7 GPa to 3.9 GPa. This is attributed to combination of shift in deformation from backbone straightening to combined backbone stretching-intermolecular sliding and subsequent strengthening of tropocollagen-water (TC-water-TC) interfaces through water bridges and intermolecular electrostatic attractions. Further increase in WC to 75% reduces the modulus to 1.8 GPa due to shift in deformation to polypeptide straightening and weakening of TC-water-TC interface due to reduced electrostatic attraction and increase in the number of water molecules in a water bridge. During axial compression, increase in WC to 50% results in increase in modulus from 0.8 GPa to 4.5 GPa. This is attributed to the combination of the development of hydrostatic pressure and strengthening of the TC-water-TC interface. Further increase in WC to 75% shifts load-bearing characteristic from collagen to water, resulting in a decrease in elastic modulus to 2.8 GPa. Such water-mediated alteration in load-bearing properties acts as foundations toward AF mechanics and provides insights toward understanding degeneration-mediated altered spinal stiffness. [ABSTRACT FROM AUTHOR]

The present work is aimed at decreasing pollutants emitted by diesel engine exhaust tailpipe and enhancing performance by incorporating cobalt oxide nanoparticles in water emulsified diesel. Water concentration of 5% and 10% is used to prepare various WD emulsion blends, with nano particle dosage levels of 50PPM and 100PPM. High speed homogenizer and ultrasonicator devices are used to disperse water droplets in diesel. Surfactant mixture of span80 and tween20 is used to achieve long term stability of emulsified fuel. The functional groups of emulsified fuel are analysed using FTIR spectroscopy. The characterization of cobalt oxide nanoparticles is carried using scanning electron microscope. Physiochemical properties such as calorific value, density, viscosity of emulsion blends and pure diesel are determined and compared. Experimental results reveal that addition of cobalt oxide nanoparticles in emulsified fuel with increased dosage of 100PPM shows 23%, 33.3%, 25%, and 44.6% reduction in NOX, HC, CO and smoke emission compared to pure diesel. The improvement in BTE and BSFC were observed for all emulsion blends. [ABSTRACT FROM AUTHOR]

Proper management, monitory and pollution controls measure should be maintained, for limited water resources, so as to reduce human health risks. Lead pollution can negatively affect human health. This study reviewed concentrations of lead in water and sediments of water bodies in Kenya, from samples or publications conducted between 1990 and 2021. Information on quantitative concentration values, locality, allowable standards, general methodology and possible pollutant sources for lead pollution in water and sediment were gathered. Based on the review, 71 concentration values (23.94%) for water, where above or similar to the Republic of Kenya (2006), maximum allowable value, with higher pollution levels in Kenya's major urban areas. The 43 sedimentary concentrations, were in the range of 198.7 mg/kg to 5.9 mg/kg. Lead concentration varied with weather patterns, in some reviews. Lead and heavy metals pollution was mainly attributed to human, industrial or agricultural activities and poor waste management. There was variation in method used by different studies. More experimental researches and modeling techniques, should be considered, for accurate methodologies, within Kenya's context. There should be proper treatment and monitoring of effluent, also human and industrial activities should be avoided near water body's banks through enforcement of riparian areas protection. [ABSTRACT FROM AUTHOR]

Human blood is made up primarily of water. Water is significantly involved in balancing the human body. It affects the component of blood like mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and mean platelets volume (MPV). The water concentration varies from 80 to 90% in blood. The change in water concentration changes the refractive index of plasma, and the change in the refractive index of plasma also changes the refractive index of blood. The proposed structure is designed to analyze the water concentration in human blood by analyzing the shifting in resonant peak and this shifting is processed by machine learning algorithm to estimate the concentration of water in human blood. Nanocavity ring structures in the waveguide region are designed as sensing nodes in this proposed structure. The air hole radius of these Nanocavity ring structures is 80 and 50 nm, whereas the proposed structure’s dimension is 12.15 by 8.45 μm2. The sensitivity of the design structure is 570 nm/RIU, and the quality factor is 650. The structure is simulated through the Finite Difference Time Domain (FDTD) method.

[Display omitted] • The nanostructure changes of the mixture at different x w were revealed by volumetric properties, RDF, SDF, CDF, C(t) and MSD. • The hydrophilic and transport properties of two AAILs – H 2 O were compared. • The structure of the mixture changed dramatically at x w = 0.7. • The aggregation state of water molecules in AAILs – H 2 O was explored. Amino acid ionic liquid - H 2 O mixtures have been widely used in recent years. Molecular dynamics (MD) simulations were used to investigate the nanostructures and interactions of two kinds of amino acid ionic liquids, 3–propyl-tributyl-alanine phosphate ([aP 4443 ][Gly]) and 3-propyl-tributyl-alanine phosphate ([aP 4443 ][Ala]) at different water molar fractions (x w = 0 – 0.95). Analysis of volume property showed that there were hydrogen (H) bonds between water molecules and ionic liquids, and the nanostructures of the mixture changed dramatically at about x w = 0.7. MD simulations showed that with the increase of water concentration, the structural correlations between anion - cation, cation - water, anion - water and water - water weakened and the relaxation time of H bonds decreased. The water molecule oxygen atoms competed with the anion carboxyl group to form H bonds with the amino group of the cation. Strong H bonds were also observed between anions and water molecules. Water molecules had different aggregation states at different water concentrations. In the concentrated ionic liquids – H 2 O mixtures, the anions and cations formed a stable network structure, and the H bonds in the system mainly consisted of H bonds between anions - cations. When 0.7 > x w ≥ 0.5, the H bonds between anion - water were the main component of H bonds in the system. When x w ≥ 0.7, the number of water - water H bonds in the mixture increased rapidly, the diffusion coefficients of the anions and cations increased exponentially, and the stable network of the ionic liquids was destroyed. The ion aggregation region was gradually divided by water molecules. When x w ≥ 0.9, water molecules were interconnected to form a large water network structure, and ionic liquids were gradually dissolved in the water molecules. [ABSTRACT FROM AUTHOR]

Anti-relaxation coatings play an important role in enhancing the polarization lifetime of polarized alkali-metal atoms. In this study, octadecyltrichlorosilane (OTS) was coated in spherical rubidium vapor cells fabricated using borosilicate glass with two stems as anti-relaxation coatings. An orthogonal experiment method was employed to obtain the optimal conditions. The results showed that OTS concentration is the dominant factor in the number of bounces, followed by the soaking time and molar ratio/(H2O:OTS). The optimal parameters were 6 mM of OTS, 6:1 of molar ratio/(H2O:OTS), and 80 min of soaking time. The number of bounces can be up to 200. Atomic force microscope images showed that the number and coverage ratio of clusters on the anti-relaxation coating fabricated by the optimized parameters are significantly less than the number and coverage ratio of clusters formed by other conditions. This means that the clusters in the coatings significantly affect the anti-relaxation performance. In addition, five OTS-coated cells were fabricated by A3B3C5 combination. However, the variability from cell to cell using the exact same preparation procedure can be up to 43.6%. The variability may be caused by the different aging times of the OTS solution. Because only one beaker of OTS solution was prepared, the OTS solution was pumped into the cells in sequence, not at the same time. [ABSTRACT FROM AUTHOR]

One of the actual challenges in fluid (oil, water and gas) transportation from wells to oil treatment installation is determination of a law of temperature distribution along the length of a pipeline at low ambient temperature. That temperature leads to increase in viscosity and deposition of wax on inner surface of a pipe. To overcome that challenge it is needed to consider several defining characteristics of formation fluid (FF) flow. Complexity of a solution is caused by two factors. From the one hand, in most cases (especially on a late stage of field development) FF is an oil emulsion (OE) that contains gas bubbles. From the other hand, temperature gradient between fluid flow and the environment has significant value (especially in the winter period of the year). At the same time, the higher content of emulsified water droplets (EWD) in OE and lower flow temperature, the higher FF viscosity, and consequently productivity (efficiency) of oil pumping system is reduced. Performed research and analysis of field experimental data showed that a function of oil viscosity versus temperature has a hyperbolic law; a function of OE viscosity versus concentration of EWD has a parabolic one. A heat balance for a certain section of a pipeline in steady state of fluid motion using a method of separation of variables was established taking into account above mentioned factors, Fourier's empirical laws on heat conductivity and Newton's law on heat transfer. As a result, unlike existing works, an exponential law of distribution of temperature along the length of a pipeline is obtained. A law takes into account nonlinear nature of change in viscosity of OE from change in temperature of flow and concentration of water in an emulsion.

An extremely affordable virus concentration method based on adsorption-elution to glass wool and subsequent reconcentration through polyethylene glycol 6000 (PEG) precipitation was optimized to recover not only non-enveloped viruses but also enveloped viruses. Hepatitis A virus (HAV) and transmissible gastroenteritis virus (TGEV) were employed as surrogates for naked and enveloped viruses, respectively, to set up the methodology. Initial experimentation in small-volume samples showed that both types of particles readily adsorbed to the positively charged glass wool but were poorly detached from it through standard elution with 0.05 M glycine with 3% of beef extract buffer, pH 9.5, with elution efficiencies of 7.2% and 2.6%, for HAV and TGEV, respectively. To improve the recovery of enveloped viruses, several modifications in the elution were assayed: increasing the elution pH, extending glass wool and eluent contact time, adding a detergent, or performing the elution by recirculation or under agitation. Considering practicability and performance, recircularization of the eluent at pH 11.0 for 20 min was the elution procedure of choice, with efficiencies of 25.7% and 18.8% for HAV and TGEV in 50 L of water. Additionally, employing 20% PEG instead of 10% for virus reconcentration improved recoveries up to 47% and 51%, respectively. The optimized procedure was applied to detect naturally occurring HAV and coronaviruses in surface water of Wadi Hanifa, Riyadh. HAV was detected in 38% of the samples, while one sample was positive for an alphacoronavirus. This cheap virus detection system enables the comprehensive surveillance of viruses present in water samples. [ABSTRACT FROM AUTHOR]

Abstract Shockwave propagation in polyethylene glycol diacrylate (PEGDA) hydrogels is simulated for the first time using nonequilibrium molecular dynamics simulations. PEGDA hydrogel models are built using the "perfect network" approach such that each crosslink junction is comprised of six chain connections. The influence of PEGDA concentration (20–70 wt%) on shock behavior is investigated for a range of particle velocities (200–1000 m/s). In agreement with reported experimental results in the literature on gels with similar densities, shock velocity and pressure in PEGDA hydrogels are found to increase with polymer concentration, within a range bounded by pure water and pure polymer behaviors. Nonlinear relationships are observed for shock pressure and shock front thickness as a function of concentration, and a logarithmic equation is proposed to describe this behavior. In addition, the relationship between pressure and shock front thickness is compared with hydrodynamic theory. Deviation from hydrodynamic predictions is observed at high particle velocities and this deviation is found to be related to viscosity changes. A power-law relationship between strain rate and pressure in PEGDA hydrogels is identified, similar to that of metals. However, a power-law exponent of 1.4 is computed for all gel concentrations, whereas an exponent of 4 is typically reported for metals. [ABSTRACT FROM AUTHOR]

Abstract Reactive species and water transport are crucial for the proton exchange membrane fuel cell operation and performance, and for this, effective flow field design can facilitate the desired transport characteristics of species. From this motivation, the conventional single serpentine flow field pattern is modified by convergent and divergent design concepts and the complex transport phenomena of the newly developed flow field designs are investigated by a numerical approach. For the numerical analyses, an experimentally validated mathematical model is developed to predict the current density, oxygen mass transport, water concentration and pressure distribution. The different configurations of modified convergent and divergent serpentine flow fields are then numerically solved and the results are compared with the conventional serpentine flow field pattern. The transport of reactive species and water concentration are analyzed from the different perspectives including cathode domains and surfaces with a quantitative formulation of the transport species. The numerical results reveals that the modified convergent serpentine flow fields yield to a uniform current density due to the lower mass fraction of water concentration over the reaction zone facilitating better oxygen mass transport and also higher channel pressure distribution along the flow field comparing the conventional and divergent type serpentine flow fields. Highlights • Novel design concept of convergent/divergent serpentine flow fields are developed. • Quantitative analyses of transport parameters for different domains. • Convergent flow field facilitates better transport character. • Convergent flow field yields to a better current distribution. [ABSTRACT FROM AUTHOR]

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Abstract: Background/purpose: The stratum corneum (SC) is the most important layer for the barrier function of skin, so investigation of the SC is very important in cosmetic and medical research. Here, we calculated the SC thickness using the depth profile of the skin's water concentration based on previously described methods, and then compared the results. Methods: Seven Korean women in their 30s participated in this study. Raman spectroscopy was used to measure the in vivo depth profile of skin water concentration. A total of 21 areas were measured at forearm. Microsoft Excel 2007 was used to calculate SC thickness based on the slope and intersection methods. Results: The slope method and the intersection method gave a forearm SC thickness calculated at 21.3 ± 2.6 μm and 17.6 ± 2.8 μm, respectively. There was a significant difference between the two calculation methods but the two methods showed strong correlation of SC thickness results (r = .899). Conclusion: Although there was a difference in calculated SC thickness of about 20% between the two methods, these results reveal that the two SC thickness calculation methods using Raman spectroscopy were suitable for measuring SC thickness, a finding consistent with other published results. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the classical parallel flow field pattern is modified by a convergent and divergent design concept for proton exchange membrane fuel cells (PEMFCs). The modification is achieved by varying the channel depth with different constant inclination gradients from the inlet to the outlet, along with the bipolar plate width which creates either a convergent or divergent flow field depending on the position of the inlet and outlet selected. The numerical model is solved to predict the cell performance including the mass transport, water vapor concentration and, pressure and current density distribution for the flow fields. The numerical results reveal that the modified convergent parallel flow fields have a better mass transport and water removal characteristics than those in the conventional one, whereas mal‐distribution of species and excessive water concentration occur in the conventional and divergent parallel flow fields. Introducing convergent parallel flow field design concept not only minimizes these issues but the cell power density is also improved by a maximum of 16%, which can show a new window in PEMFC flow field design concept. [ABSTRACT FROM AUTHOR]

In this paper, a way of quantification of the water-to-lipid ratio in aqueous suspensions of phospholipid vesicles by Raman spectroscopy is suggested. We measured the ratio of Raman intensities of the OH stretching band and the symmetric CH 2 -stretching mode for series of water suspensions of different phosphatidylcholines with varied water-to-phospholipid ratio. It is shown that there is a simple linear relation between the ratio of Raman intensities and the water-to-lipid ratio if the number of CH 2 groups in the hydrocarbon chains is taken into account. The proportionality coefficient of this relation is determined for the gel and fluid phases of phospholipids. [ABSTRACT FROM AUTHOR]

Water has a fatal influence on the performance of lithium ion batteries. In this work, Lithium hexafluoro phosphate(LiPF 6 )-ethylene carbonate (EC)/diethyl carbonate (DEC) and lithium bis(oxalato)borate (LiBOB)-tetramethylene sulfone (SL)/DEC are taken as examples to investigate the influences of water concentration for electrochemical window, acidity, impedance and cycling performance for lithium ion batteries by adjusting water concentrations in the electrolytes. Results show that LiBOB-based electrolyte has better water tolerance compared with LiPF 6 -based system, due to the formation of LiBOB·xH 2 O compounds by consuming the additive trace water. Besides, inductively coupled plasma test result shows that Mn ion dissolution in LiPF 6 systems is extremely severe, which is mainly caused by the corrosive reaction between LiMn 2 O 4 and by-product HF acid. And we believe that Mn ion dissolution and the following deposition should be responsible for failure work of LiPF 6 -based cells. But for LiBOB-based cells, stable SEI layers and good electrochemical performances have been obtained, benefitting from the synergistic effect between LiBOB salt and SL solvent. And the presence of high-resistance B(C 2 O 4 ) (OH) and LiB(C 2 O 4 ) (OH) 2 products on surface of graphite electrode is the main reason for a small number of capacity fading. [ABSTRACT FROM AUTHOR]

The present work aims to investigate emulsion fuel characteristics with different levels of water concentration and their effects on performance and emissions of a light-duty diesel engine. The engine was operated at three engine speeds of 1000, 2100 and 3000 rpm, respectively. At each speed, three loads (20%, 50%, and 80%) were applied. Diesel and biodiesel-diesel blends up to 40 by step of 10 were emulsified with three different levels of water concentration (5%, 10% and 15%). Emulsifiers Sorbitan Monoleate (Span 80) and Polyoxyethylene Sorbitan Monoleate (Tween 80) were used to prepare emulsion fuels. Fuel properties, stability and particle size distribution were measured. Engine performance (brake-specific fuel consumption (BSFC) and brake thermal efficiency (BTE)) and emissions were investigated. An increase in BTE was observed with increased water content in emulsions. A reduction in exhaust gas temperature (EGT) with an increase in water content was achieved. The nitrogen oxides (NOx) and smoke emissions were also significantly reduced with the increase in water content in the emulsion compared to their bases. Emulsion fuel containing a higher water content revealed a considerable increase in carbon monoxide (CO) emissions. [ABSTRACT FROM AUTHOR]

From the results of experimental studies of the processes of suppressing the thermal decomposition of the typical forest combustibles (birch leaves, fir needles, asp twigs, and a mixture of these three materials) by water aerosol, the minimum volumes of the fire-extinguishing liquid have been determined (by varying the volume of samples of the forest combustibles from 0.00002 m to 0.0003 m and the area of their open surface from 0.0001 m to 0.018 m). The dependences of the minimum volume of water on the area of the open surface of the forest combustible have been established. Approximation expressions for these dependences have been obtained. Forecast has been made of the minimum volume of water for suppressing the process of thermal decomposition of forest combustibles in areas from 1 cm to 1 km, as well as of the characteristic quenching times by varying the water concentration per unit time. It has been shown that the amount of water needed for effective suppression of the process of thermal decomposition of forest combustibles is several times less than is customarily assumed. [ABSTRACT FROM AUTHOR]

The influence of water concentrations on phase transformations of a surfactant/co-surfactant/water system is investigated by using all atom molecular dynamics simulations. At higher water concentrations, where surfactant (behenyl trimethyl ammonium chloride, BTMAC) to co-surfactant (stearyl alcohol, SA) ratio is fixed, BTMAC and SA self-assemble into spherical micelles, which transform into strongly interdigitated one dimensional rippled lamellar phases upon decreasing water concentrations. Fragmentation or fusions of spherical micelles of different sizes are evident from the radial distribution functions at different temperatures. However, at lower water concentrations rippled lamellar phase transforms into an L β I phase upon heating. Our simulations reveal that the concentrations of water can influence available space around the head groups which couple with critical thickness to accommodate the packing fraction required for respective phases. This directs towards obtaining a controlling factor to design desired phases important for industrial and medical applications in the future. [ABSTRACT FROM AUTHOR]

Glycols are key chemicals for many applications in different fields of activities. Being highly hydroscopic, glycols contain usually water. The presence of water, even in tiny amounts, can affect their chemical and physical properties. Therefore, the accurate determination of water content is essential for any intended applications. In this context, a novel method using low-field Nuclear Magnetic Resonance (NMR) spectroscopy is introduced. The proposed approach offers a straightforward, fast, low-cost, and versatile solution for water quantification in glycols without the need for reagents or calibration data. It is demonstrated by quantifying the water concentration up to 11 wt% in aqueous ethylene glycol (EG) and triethylene glycol (TEG) mixtures with the help of lineshape analysis of the corresponding proton spectra. The limit of detection, achieved within 1 min of measuring time, was 0.05 wt% for water in EG and 0.15 wt% in TEG. The excellent agreement between the NMR results and those from the Karl-Fischer titration indicates that the proposed NMR-based approach has a great potential to be used as an alternative to the Karl-Fischer method. In addition, it is expected that the same methodology can be applied for water quantification in more complex glycolic solutions and other mixtures. [Display omitted] • Novel method for quantifying water concentration up to 11 wt% in glycols. • The proposed approach uses compact 1H NMR spectroscopy. • Limit of detection of water is 0.05 wt% in EG and 0.15 wt% in TEG. • 1H low-field NMR spectroscopy as alternative to standard Karl-Fischer method. [ABSTRACT FROM AUTHOR]

The improvement of Carbon dioxide (CO 2 ) separation efficiency from flue gases to reduce the total energy cost of sequestration technologies in coal-fired power plants has been identified as a high-priority research area. In the past three decades, membranes have attracted the attention of chemists and engineers due to their unique separation principles (i.e., selective transport and efficient separation compared to other unit operations). In this study, the formation of cellulose acetate (CA) membrane for CO 2 /nitrogen (N 2 ) separation was investigated by wet phase inversion. In order to modify the CA membrane structure, different concentration ratio of solvent mixture (acetic acid:water), acetic acid and water were studied. The CA membranes were analyzed by Fourier transform infrared spectroscopy (FTIR). The separation results supported by the characterization, where the best formulate membrane with solvent mixture ratio of 70:30 (acetic acid:water), acetic acid concentration of 63 wt% and water concentration of 27 wt% had high CO 2 permeance of 400.92 GPU and slightly better CO 2 /N 2 separation performance at 32.92 as compared to others literature. [ABSTRACT FROM AUTHOR]

The collection of waterborne pathogen occurrence data often requires the concentration of microbes from large volumes of water due to the low number of microorganisms that are typically present in environmental and drinking waters. Hollow-fiber ultrafiltration (HFUF) has shown promise in the recovery of various microorganisms. This study has demonstrated that the HFUF primary concentration method is effective at recovering bacteriophage φX174, poliovirus, enterovirus 70, echovirus 7, coxsackievirus B4 and adenovirus 41 from large volumes of tap and river water with an average recovery of all viruses of 73.4% and 81.0%, respectively. This study also evaluated an effective secondary concentration method using celite for the recovery of bacteriophage and enteric viruses tested from HFUF concentrates of both matrices. Overall, the complete concentration method (HFUF primary concentration plus celite secondary concentration) resulted in a concentration factor of 3333 and average recoveries for all viruses from tap and river waters of 60.6% and 60.0%, respectively. [ABSTRACT FROM AUTHOR]

Incident radiation strongly influences fruit development, but little is known regarding the specific responses to the radiation differences found at different canopy heights and orientations in the new intensive hedgerow orchards. We tested the effect of position-determined solar microenvironment on olive fruit size, composition, and cellular development among positions at successive heights along both faces of N–S and E–W oriented olive hedgerows (cv. Arbequina). Total incident irradiance over the fruit growth period at each canopy position was modeled, and the relationships of all fruit parameters to irradiance and amongst each other were tested. Fruit and mesocarp weight and oil increased from canopy base to top and were linearly related to irradiance, while water content showed the opposite pattern, suggesting that priorities for distribution among different sinks are strongly influenced by irradiance level. Similar patterns of fruit size and composition in relation to irradiance were also observed among hedgerow orientations. Endocarp weight and composition varied little among irradiance levels, reflecting the conservative nature of this tissue as an active sink. Greater fruit size, mesocarp weight, and oil in positions of higher irradiance, even when fruit number was higher, indicating that those yield components were primarily affected by source supply and not limited by sink competition. Fruit exposed to light developed larger mesocarp cells than shaded fruit but cell number was not affected, and mesocarp oil content was highly associated with mesocarp cell size. [ABSTRACT FROM AUTHOR]