Showing papers on "Distilled water published in 2019"
TL;DR: In this paper, a photovoltaic thermal collector has been constructed in Karabuk University, Turkey to investigate the effects of utilizing multiwalled carbon nanotubes (MWCNT) and graphene nanoplatelets dispersed in water as a base fluid with a concentration of 0.5
85 citations
TL;DR: The results suggested the as-prepared fertilizer had good abilities to retain water and control urea release, and the addition of halloysite helped to improve the release properties of the fertilizer.
69 citations
TL;DR: In this paper, a new plant-base natural surfactant, named Tribulus Terrestris is introduced and combined with smart water samples (i.e., synthetic seawater with different concentrations of active Ca2+, Mg2+ and SO42− ions) to determine their individual and integrated effects on reduction in interfacial tension, wettability alteration and oil recovery in carbonate rock samples.
57 citations
30 Jul 2019
TL;DR: In this paper, the effect of salinity on evaporation from water bodies and probable influence on the water cycle was studied and it was shown that salinity effects will impact on the outflow parameter in water cycle with consequent reduction in evapuration which reduces precipitation, hence the formation of rain in the cloud would be inhibited and ultimately lead to climate change.
Abstract: This study is on the effect of salinity on evaporation from water bodies and probable influence on the water cycle. Five different salts were used in this study, different concentrations of Magnesium Sulphate, Sodium Hydroxide, Sodium Chloride, Ammonium Chloride and Potassium Nitrate solutions in the neighbourhood of 0.04, 0.08, 0.12, 0.16, 0.20 and 0.24 g/cm 3 were prepared by dissolving 20, 40, 60, 80, 100 and 120 g weights of these salts in 500 cm 3 of distilled water. The first evaporation can contained only 500 cm 3 of distilled water and served as the control experiment. The solutions were introduced in evaporation cans each of capacity 700 cm 3 , stored under room temperature and evaporation allowed to take place. Evaporation from the cans were measured at 24 hours intervals for a period of 14 days. Results showed that in all salts, as salinity increases, evaporation is reduced. On the 10th day, evaporation retardation factors for Magnesium Sulphate, Sodium Hydroxide, Sodium Chloride, Ammonium Chloride and Potassium Nitrate were found to be 0.800, 0.490, 0.712, 0.820 and 0.822 respectively. Ratios of evaporation retardation factors were 1:1.6327 for Sodium hydroxide : Magnesium Sulphate; 1:1.4531 for Sodium Hydroxide : Sodium Chloride; 1:1.6735 for Sodium Hydroxide : Magnesium Sulphate; 1:1.4531 for Sodium Hydroxide: Sodium Chloride; 1:1.6327 for Sodium Hydroxide : Ammonium Chloride and 1:1.6776 for Sodium Hydroxide : Potassium Nitrate solutions. Highest evaporation took place in Potassium Nitrate solution at the ultimate concentration of 0.24 g/cm 3 , this was followed by Ammonium Chloride, Magnesium Sulphate, Sodium Chloride and Sodium Hydroxide. These salinity effects will impact on the outflow parameter in the water cycle with consequent reduction in evaporation which reduces precipitation, hence the formation of rain in the cloud would be inhibited and ultimately lead to climate change.
54 citations
TL;DR: The swelling kinetic mechanism of the SAR was explained by the pseudo-second-order swelling kinetics model and Ritger-Peppas model, and the effects of soil type, particle size and content of SAR on water evaporation rate in soil were studied.
53 citations
TL;DR: Rainbow trout minces were minced and subjected to different preparing methods including simple distilled water washing, calcium chloride+citric acid washing or their combinations, prior to hydrolysis as mentioned in this paper.
Abstract: Rainbow trout by-product was minced and subjected to different preparing methods including simple distilled water washing, calcium chloride + citric acid washing or their combinations, prior to hydrolysis. Particle diameter and zeta potential of the homogenized by-product were ∼45 nm and −23 mV, respectively. Less thiobarbituric acid-reactive substances (TBARS) and protein carbonyls were formed during hydrolysis when minces were washed with distilled water (BPW-FPI) or distilled water prior to calcium chloride + citric acid washing (W-CaCi-BPFPI) (P
49 citations
TL;DR: In this article, a Direct Contact Membrane Distillation system using a flat-sheet membrane module was fabricated to experimentally study the effects of operating conditions (inlet temperatures and flow rates of feed and permeate streams and salt concentration) on its distilled water production.
46 citations
TL;DR: In this paper, the authors synthesize smart superabsorbent hydrogels consisting of acrylamide/sodium alginate (AS), AS, ASAx, and 2-acrylamido-2-methylpropane sulphonic acid (ASAx, x = amount of AMPS) via free radical polymerization.
Abstract: Smart superabsorbent hydrogels consisting of acrylamide/sodium alginate (AS), acrylamide/sodium alginate/2-acrylamido-2-methylpropane sulphonic acid (ASAx, x = amount of AMPS) were synthesized via free radical polymerization. The swelling behavior of the hydrogels was studied in distilled and tap water. It was found that by increasing the amount of 2-acrylamido-2-methylpropanesulphonic (AMPS) in the hydrogel composition, the hydrogel swelling capability was enhanced from 3685% for AS to 4797% for ASA1 and 21 175% for ASA2 in distilled water, while in tap water this property varied from 915% for AS to 988% and 1588% for ASA1 and ASA2, respectively. All the samples were found to be efficient for the removal of crystal violet from aqueous solution. The absorption efficiency and % removal increased from 1.78 mg g−1 and 62.6% for AS to 3.31 mg g−1 and 75% for ASA1 and 3.34 mg g−1 and 82.1% for ASA2. The effects of pH, contact time, initial dye concentration and hydrogel dosage on the removal process were studied in detail. The mechanism of CV removal occurs according to the Freundlich isotherm following pseudo second order kinetics. The thermodynamic parameters showed that the sorption process is spontaneous and endothermic in nature. The superabsorbent hydrogels were regenerated and reused in six consecutive cycles with 5% decrease in efficiency.
45 citations
TL;DR: The use of water hyacinth, a notorious weed in Kenyan waters, to produce cellulose-based polymer hydrogels has not been explored and yet, it could form an effective and beneficial way of utilizing this plant.
42 citations
TL;DR: It was found that photocatalytic reactions were capable of achieving up to 100% bacterial inactivation in 1 h of treatment, following a pseudo-first order kinetic model, and no bacterial regrowth was observed after photoc atalytic treatments in almost all experimental conditions.
Abstract: Fabrics obtained from cellulose spinning, extracted from Spanish broom, were coated with TiO2 film, through the low pressure plasma sputtering technique, in order to get antibacterial activity. The obtained fabrics were used for the photocatalytic degradation of Escherichia coli, by irradiation with UV-light emitting diodes (UV-LED), in a batch photocatalytic reactor. Before and after functionalization treatments, cellulosic substrates were chemically characterized by X-ray photoelectron spectroscopy (XPS) analyses. Water Contact Angle (WCA) measurements allowed obtaining information about the hydrophilicity of the materials, while their antibacterial efficiency was determined at several initial concentrations (from 103 up to 108 CFU mL−1) of bacteria in distilled water, bottled water and synthetic wastewater. It was found that photocatalytic reactions were capable of achieving up to 100% bacterial inactivation in 1 h of treatment, following a pseudo-first order kinetic model. No bacterial regrowth was observed after photocatalytic treatments in almost all experimental conditions. In contrast, during photolytic treatment (i.e. in the absence of the TiO2 coated fabrics) bacteria recovered their initial concentration after 3 h in the dark. Finally, the reusability of the plasma modified fibers to inactivate bacteria was studied.
37 citations
TL;DR: In this paper, the degradation of 2,4-dichlorophenoxy acetic acid (2,4D) using UV irradiation and the UV-H 2 O 2 advanced oxidation process (AOP) was investigated.
TL;DR: In this paper, pH-sensitive superabsorbent polymers (SAPs) have been successfully synthesized through copolymerization of 2-(Dimethylamino)ethyl methacrylate (DMAEMA) and acryloyloxyethyltrimethyl ammonium chloride (DAC) to achieve self-healing of microcracks in cement sheath.
Abstract: Poor zonal isolation due to microcracks in cement sheath is a common problem that affects oil and gas exploration and also impacts the environment. In this study, pH-sensitive superabsorbent polymers (SAPs) have been successfully synthesized through copolymerization of 2-(Dimethylamino)ethyl methacrylate (DMAEMA) and acryloyloxyethyltrimethyl ammonium chloride (DAC) to achieve self-healing of microcracks in cement sheath. The chemical structure of p(DMAEMA-co-DAC) SAP was characterized using Fourier transform infrared (FTIR) spectroscopy. Water absorption tests determined the effect of cross-linker dosage and DMAEMA/DAC molar ratio on their water absorption rate (WAR). pH-sensitive tests showed they absorbed considerable water in neutral and weak alkaline solutions but little water in strong alkaline solutions. In addition, the WARs were quite small in high concentration calcium chloride solutions. The WARs in distilled water reduced after they were processed in cement slurry filtrate (CSF) due to hydrolysis of ester groups and the crosslinking effect of Ca 2 + ions. Additionally, the SAP showed good compatibility with the cement slurry. It had little impact on the thickening time, rheological property, fluid loss, and early compressive strength of cement slurry/stone. Eventually, sealing pressure test results indicated the self-healing properties of p(DMAEMA-co-DAC) SAP-modified oil well cement. Using a 2 wt.% SAP addition, microcracks up to 166 μ m can be sealed.
TL;DR: In this paper, a novel hybrid system was designed for petrochemical wastewater treatment and reuse by coupling membrane distillation (MD) with a two-stage pretreatment process comprising oil/water separation and photocatalytic organics degradation.
TL;DR: In this article, ground water samples from residential homes in three Regions of Ghana: Central, Greater Accra and Ashanti, were analyzed for iron and manganese contamination by X-ray diffraction, scanning electron microscopy and thermal analysis.
Abstract: Ground water samples from residential homes in three Regions of Ghana: Central, Greater Accra and Ashanti, were analyzed for iron and manganese contamination. The samples were exposed to characterized zeolite Y by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transformed-infrared spectroscopy and thermos gravimetric-differential thermal analysis. Zeolite Y is able to remove 98% of iron and 97% of manganese within an hour. The adsorption of both iron and manganese followed the Freundlich model, suggesting that the ions were transported onto the zeolite Y surface and subsequently diffused into the zeolite Y framework. The kinetic studies showed that pseudo-first order and intra particle and film diffusion models provided the best fit. The adsorption at 0.2 mg L−1 Fe ( Q 0.2 ) is calculated to be 0.023 mg g−1 for the Freundlich adsorption model, whilst that of manganese at 0.05 mg L−1 Mn ( Q 0.05 ) is evaluated to be 0.015 mg g−1. The zeolite retains its adsorption properties when retrieved from the first exposure water sample, washed copiously with distilled water and added to fresh water samples. The results suggest that zeolite Y can be used as a potential adsorbent for the removal of iron and manganese from groundwater.
TL;DR: In this paper, a compact loop heat pipe with distilled water, silver (Ag)/water and aluminium oxide (Al2O3)/water nanofluid having low volume concentrations of (0.09% and 0.12%).
Abstract: The heat transfer performance and entropy analysis are done in a compact loop heat pipe (CLHP) with Al2O3/water and Ag/water nanofluid. A compact loop heat pipe having a flat square evaporator with dimensions of 34 mm (L) × 34 mm (W) × 19 mm (H) has been fabricated and tested for the heat load ranging from 30 to 500 W. The experimental tests are conducted by keeping the CLHP in the vertical orientation with distilled water, silver (Ag)/water and aluminium oxide (Al2O3)/water nanofluid having low volume concentrations of (0.09% and 0.12%). The effect of wall and vapour temperature, evaporator and condenser heat transfer coefficient, thermal resistance on the applied heat loads is experimentally investigated and compared. The experimental results showed that the evaporator thermal resistance is reduced by 34.70% and 20.21%, respectively, for 0.12 vol% of Ag, Al2O3 nanoparticles when compared with that of the distilled water. For the same volume concentrations of Ag, Al2O3 nanoparticles, an enhancement of 34.52%, 23.7%, 39.27% and 30.8%, respectively, observed for the convective heat transfer coefficients at the evaporator and condenser. The entropy is also reduced by 19.08% and 11.58% when Ag and Al2O3 nanofluids are used as the operating fluid. From the experimental tests, it is found that the addition of small amount of Ag nanoparticles in the working fluid enhanced the operating range by 15% when compared with that of Al2O3/water nanofluid without the occurrence of any dry-out conditions.
TL;DR: In this paper, a modified solar still augmented with copper tube heat exchanger in coarse aggregate has been carried out and compared with conventional still performance under the same climatic conditions, and the results indicate that the modified still has higher energy and exergy efficiencies and better water quality with cumulative yield.
Abstract: In this paper, the thermodynamic (energy and exergy) analysis and water analysis of a modified solar still augmented with copper tube heat exchanger in coarse aggregate have been carried out and compared with conventional still performance under the same climatic conditions. Basin water temperature, solar intensity, wind velocity, cumulative yield, water conductivity, total hardness, pH value and fluoride concentration are obtained from experimental results for saline, basin and distilled water. Energy efficiency, evaporation and convective heat transfer coefficient, exergy evaporation rate and exergy efficiency are determined from energy and exergy analysis. The results show that the modified still has an efficiency of 28% and 17% greater than the conventional still. The productivity of modified and conventional still is 6.23 kg m−2 and 2.41 kg m−2, respectively. The exergy efficiency depends on the time of the test day and reaches a maximum value of 5.5% and 1.1%, respectively, for the modified and conventional still. From the water analysis, it is observed that the maximum distilled water pH, water conductivity, hardness and fluoride content are 7.5, 0.8 × 10−4 S m−1 (0.8 µS cm−1), 0.5 × 10−3 kg m−1 (0.5 mg L−1) and 0.7 × 10−3 kg m−3 (0.7 mg L−1), respectively, with the still salinity removal efficiency of 99%. The results indicate that the modified still has higher energy and exergy efficiencies and better water quality with cumulative yield.
TL;DR: In this paper, the authors used microwave and high-pressure homogenization (HPH) to obtain C-phycocyanin (C-PC) from cyanobacteria Arthrospira maxima.
Abstract: Cyanobacteria are a rich source of bioactive compounds, mainly in the Arthospira sp., and one of the most interesting components in recent years has been C-phycocyanin (C-PC). There have been several conventional methods for their extraction, among which stand out: chemical products, freezing-thawing (FT); enzymatic, and maceration (M); which have come to be replaced by more environmentally friendly methods, such as those assisted by microwaves (MW) and high-pressure homogenization (HPH). The aim of the research was to use these two “green extraction processes” to obtain C-PC from cyanobacteria Arthrospira maxima because they improve functionality and are fast. Extractions of C-PC were studied by means of two experimental designs for MW and HPH, based on a response surface methodology (RSM) employing, firstly, a factorial design 33: power (100, 200, and 300 W), time (15, 30, and 60 s), and types of solvents (distiller water, Na-phosphate buffer and, distiller water: Na-phosphate buffer (Ph 7.0; 1:1, v/v); and secondly, two factors with different levels: Pressure (800, 1000, 1200, 1400, and 1600 bar) and, types of solvents (distilled water, Na-phosphate buffer (pH 7.0) 100 mM and, Na-phosphate buffer:water 1:1, (v/v)). Optimum C-PC content was achieved with the HPH process under Na-phosphate solvent at 1400 bar (291.9 ± 6.7 mg/g) and the MW method showed improved results using distilled water as a solvent at 100 W for 30 s (215.0 ± 5.5 mg/g). In the case of conventional methods, the freeze–thawing procedure reached better results than maceration using the buffer (225.6 ± 2.6 mg/g). This last one also did not show a significant difference between solvents (a range of 147.7–162.0 mg/g). Finally, the main advantage of using green extractions are the high C-PC yield achieved, effectively reducing both processing times, costs, and increasing the economic and functional applications of the bioactive compound.
TL;DR: In this paper, a leakage transformer, energizing two metal electrodes positioned above the liquid, limits the discharge current inductively by utilizing the weak magnetic coupling between the primary and secondary coils.
Abstract: A new configuration of a discharge chamber and power source for the treatment of up to 1 L of liquid is presented. A leakage transformer, energizing two metal electrodes positioned above the liquid, limits the discharge current inductively by utilizing the weak magnetic coupling between the primary and secondary coils. No additional means to avoid arcing (electric short-circuiting), e.g., dielectric barriers or resistors, are needed. By using this technique, exceeding the breakdown voltage leads to the formation of transient spark discharges, producing non-thermal plasma (NTP). These discharges effected significant changes in the properties of the treated liquids (distilled water, physiological saline solution, and tap water). Considerable concentrations of nitrite and nitrate were detected after the plasma treatment. Furthermore, all tested liquids gained strong antibacterial efficacy which was shown by inactivating suspended Escherichia coli and Staphylococcus aureus. Plasma-treated tap water had the strongest effect, which is shown for the first time. Additionally, the pH-value of tap water did not decrease during the plasma treatment, and its conductivity increased less than for the other tested liquids.
TL;DR: In this article, the authors evaluated the effect of chitosan and water solubility on refrigerated catfish fillet quality, and showed that the results showed both the advantages and limitations of applying chitusan or water-solubility for preserving catfish quality during refrigerated storage.
Abstract: Chitosan’s water insolubility restricts its use in some food systems. However, when treated with enzymes, a water-soluble chitosan is developed, which overcomes insolubility. The aim of this study was to evaluate the effect of chitosan and water-soluble chitosan applications on refrigerated catfish fillet quality. Fresh catfish fillets were separately vacuum tumbled with distilled water, 1% acetic acid, chitosan (0.5% in acetic acid), and water-soluble chitosan (0.5% in distilled water). Sampling was done at 0, 5, 10, 15, and 20 days. The fillets were analyzed for lipid oxidation, aerobic plate counts, yeast and mold counts, cutting force, color, and pH. Triplicate experiments were done and the data were statistically analyzed at a significance level of 0.05. Water-soluble chitosan had 86 ± 2% water solubility compared to 1.9 ± 0.2% for chitosan. Fillets treated with water-soluble chitosan solution had lipid oxidation reduced by approximately 70% compared to untreated fillets during 20 days of refrigerated storage. Chitosan treated fillets showed the highest inhibition with aerobic plate, yeast and mold counts. Initially, fillets treated with acetic acid and chitosan solutions had a more rapid decrease in hardness than those vacuum tumbled with water-soluble chitosan and distilled water. Therefore, this study showed both the advantages and limitations of applying chitosan or water-soluble chitosan for preserving catfish fillet quality during refrigerated storage.
TL;DR: In this paper, the authors analyzed the chemical component change in betung bamboo strands after different steam and washing treatments, and their influence on the physical and mechanical properties of bamboo-oriented strand boards (BOSB).
Abstract: The purpose of this study was to analyze the chemical component change in betung bamboo (Dendrocalamus asper (Schult. & Schult. F.) Backer ex K. Heyne) strands after different steam and washing treatments, and their influence on the physical and mechanical properties of bamboo-oriented strand boards (BOSB). Strands were prepared with three different treatments: (1) steam-only, (2) steam followed by washing with distilled water, and (3) steam followed by washing with 1% sodium hydroxide solution. The steaming process was performed at 126 °C for 1 h at a pressure of 0.14 MPa. Chemical components such as holocellulose, alpha-cellulose, lignin, and starch were analyzed. Phenol formaldehyde resin was used to manufacture BOSB, and the physical and mechanical properties were evaluated in the final products. Steam treatments resulted in changes in chemical components that affected the physical and mechanical properties of BOSB. These changes were mainly caused by the degradation of hemicellulose and extractives dissolved in hot water or 1% sodium hydroxide. These treatments increased the bonding between strands, resulting in higher dimensional stability and strength of BOSB. Considering all the performed experiments, the steam treatment followed by washing with 1% sodium hydroxide was the best treatment for manufacturing BOSB.
TL;DR: In this paper, the effects of an aluminum high temperature conductive microporous coating (Al-HTCMC) on the nucleate boiling heat transfer (NBHT) coefficient and critical heat flux (CHF) are studied in saturated distilled water at 1 atm.
TL;DR: All CH pastes tested here were effective in reducing Enterococcus faecalis and were similar in the penetration, pH, calcium ion release, and solubility of calcium hydroxide when compared to distilled water.
Abstract: This in vitro study compared the penetration, pH, calcium ion release, solubility, and intradentinal decontamination capacity of calcium hydroxide (CH) pastes with different vehicles and additives. Infected standard bovine dentine contaminated with Enterococcus faecalis were treated with propolis extract, chlorhexidine, and camphorated paramonochlorophenol (CPMC) loaded in CH paste for the bacterial viability evaluation made by confocal laser scanning microscopy (CLSM) and microbiological culture. Beside this, 50 acrylic teeth were filled with the previously mentioned pastes to evaluate the pH and calcium ion release (pHmeter and atomic absorption spectrophotometer at time intervals of 7, 15, and 30 days) and solubility (micro-computed tomographic imaging before and after 15 days). After treatment, all samples decreased intra-dentinal contamination, specially, the CH paste with CPMC. There was no statistically significant difference between the groups when evaluating the intra-canal paste penetration. In the pH measurements, CH with distilled water showed the smallest pH values. Regardless the solubility percentage of the pastes, the paste of CH + PG presented the highest values. The vehicles and additives tested may increase CH antimicrobial effect, but with small differences. In general, all CH pastes tested here were effective in reducing Enterococcus faecalis and were similar in the penetration, pH, calcium ion release, and solubility of calcium hydroxide when compared to distilled water. The use of calcium hydroxide pastes as intracanal medication with an aqueous or viscous vehicle, as propylene glycol, can be useful, since all formulations of the tested pastes resulted in great bacterial reduction inside root canals.
17 Oct 2019
TL;DR: In this paper, the authors tested four leaching solutions (distilled water and three organic acids) and determined the optimum reaction conditions to determine the optimum leaching solution for concrete kiln dust (CKD).
Abstract: Cement kiln dust (CKD) is a major by-product of cement manufacturing and has the potential to be recycled as a raw material if the high concentrations of chlorine and potassium are removed. This study tested four leaching solutions (distilled water and three organic acids) and determined the optimum reaction conditions. At a liquid/solid (L/S ratio) of 10, the removal efficiency of formic, citric, and oxalic acid was higher than that of distilled water, but at L/S 20, distilled water also achieved a high removal efficiency of Cl (≥90%) and K (≥70%). In addition, to minimize the discharge of wastewater after leaching, the efficiency of ion-exchange resins for the recovery of leaching solution was tested. When the cation- and anion-exchange resins were arranged together, more than 95% of both Cl and K contained in the leaching solution could be removed. Leaching solution without Cl and K was found to have a high leaching efficiency even after being recycled three times, resulting in a significant reduction in wastewater emissions.
TL;DR: In this article, the dynamic viscosity, surface tension and wetting behavior of phase change material nano-emulsions (PCMEs) formulated at dispersed phase concentrations of 2, 4 and 10 wt.%.
Abstract: This work analyzes the dynamic viscosity, surface tension and wetting behavior of phase change material nano–emulsions (PCMEs) formulated at dispersed phase concentrations of 2, 4 and 10 wt.%. Paraffin–in–water samples were produced using a solvent–assisted route, starting from RT21HC technical grade paraffin with a nominal melting point at ~293–294 K. In order to evaluate the possible effect of paraffinic nucleating agents on those three properties, a nano–emulsion with 3.6% of RT21HC and 0.4% of RT55 (a paraffin wax with melting temperature at ~328 K) was also investigated. Dynamic viscosity strongly rose with increasing dispersed phase concentration, showing a maximum increase of 151% for the sample containing 10 wt.% of paraffin at 278 K. For that same nano–emulsion, a melting temperature of ~292.4 K and a recrystallization temperature of ~283.7 K (which agree with previous calorimetric results of that emulsion) were determined from rheological temperature sweeps. Nano–emulsions exhibited surface tensions considerably lower than those of water. Nevertheless, at some concentrations and temperatures, PCME values are slightly higher than surface tensions obtained for the corresponding water+SDS mixtures used to produce the nano–emulsions. This may be attributed to the fact that a portion of the surfactant is taking part of the interface between dispersed and continuous phase. Finally, although RT21HC–emulsions exhibited contact angles considerably inferior than those of distilled water, PCME sessile droplets did not rapidly spread as it happened for water+SDS with similar surfactant contents or for bulk–RT21HC.
TL;DR: In this article, an aliphatic anion exchange membrane was prepared from quaternized polyvinyl alcohol (QPVA) via dual cross-linking through annealing treatment and condensation reaction to restrain the membrane water swelling.
TL;DR: Pretreatments of blanching (BL), osmotic dehydration at 35°Brix of sucrose (OD), ultrasound in distilled water (UD), and ultrasound-assisted osalotic dehydration (UO) were carried out for microwave-assisted OSA.
Abstract: Pretreatments of blanching (BL); osmotic dehydration at 35°Brix of sucrose (OD); ultrasound in distilled water (UD), and ultrasound-assisted osmotic dehydration (UO) were carried out for microwave-...
TL;DR: In this paper, water-soluble Cu nanoparticles of size approximately 3 nm were prepared at room temperature (around 25 °C) via in-situ surface modification, and the tribological behavior of the as-synthesized CU nanoparticles as an additive in distilled water was evaluated using a universal micro-tribotester.
Abstract: Efficient and sustainable use of water-based lubricants is essential for energy efficiency. Therefore, the use of water-lubricated mechanical systems instead of conventional oil lubricants is extremely attractive from the viewpoint of resource conservation. In this study, water-soluble Cu nanoparticles of size approximately 3 nm were prepared at room temperature (around 25 °C) via in-situ surface modification. The tribological behavior of the as-synthesized Cu nanoparticles as an additive in distilled water was evaluated using a universal micro-tribotester. The results show that the as-synthesized Cu nanoparticles, as a water-based lubricant additive, can significantly improve the tribological properties of distilled water. In particular, the lowest friction coefficient of 0.06 was obtained via lubrication with a concentration of 0.6 wt% of Cu nanoparticles in distilled water, which is a reduction of 80.6% compared with that obtained via lubrication with distilled water alone. It is considered that some Cu nanoparticles entered the contact area of the friction pairs to form a complex lubricating film and prevent direct contact of the friction pairs. Furthermore, some Cu nanoparticles in the solution accelerate the heat transfer process, which also results in good tribological properties.
TL;DR: Water storage seems to have a much more pronounced effect on the mechanical properties of Ormocer®-based dental composites in comparison to Bis-GMA-based composites.
Abstract: The aim of the study was to evaluate the mechanical stability of bisphenol A-glycidyl methacrylate (Bis-GMA) and Ormocer-based resin composites before and after water absorption and to examine water saturation. Disc-shaped specimens of the Bis-GMA (Grandio SO, Voco) and the Ormocer-based (Admira Fusion, Voco) dental resin composites were produced, stored in water, and weighed after pre-determined times to measure the absorbed water. Bend bars were produced and stored for 24 h in dry conditions as well as in distilled water for 14 days or 60 days at 37 °C. The initial flexural strength (FS) under quasi-static loading and flexural fatigue strength (FFS) under cyclic loading were determined under 4-point bending. Fracture toughness (KIc) of both composites was measured using the single-edge-V-notch-beam (SEVNB) technique after the same storage conditions under 3-point bending. Within the first 14 days, storage conditions did not affect the initial FS of Grandio SO, while a significant drop in initial FS was observed for Admira Fusion after 2 weeks in water and most of the water was absorbed within this time. FFS for the Bis-GMA composite was not reduced before 2 months in water, whereas for the Ormocer®-based composite, there has been a significant decrease in strength after cyclic fatigue already at 2 weeks of water storage. KIc of Admira Fusion decreased significantly after both storage periods, while KIc of Grandio SO decreased only significantly after 2 weeks of water storage. All mechanical properties of the Bis-GMA composite were superior to those of the Ormocer®-based material, except water sorption. Water storage seems to have a much more pronounced effect on the mechanical properties of Ormocer®-based dental composites in comparison to Bis-GMA-based composites.
TL;DR: The results show that the reason for the lower photocatalytic activity in the presence of SiO32- than in its absence was due to adsorption of Si O32- onto the surface of the TiO2 photocatalyst and that SiO 32- advertisersorption was an equilibrium process in water.
TL;DR: In this paper, the problem of pool boiling heat transfer enhancement on metal wire mesh coatings made of copper and phosphor bronze at nucleate boiling of distilled water and high purity ethyl alcohol under ambient pressure was dealt with.
Abstract: The article deals with the problem of pool boiling heat transfer enhancement on metal wire mesh coatings made of copper and phosphor bronze at nucleate boiling of distilled water and high purity ethyl alcohol under ambient pressure. The tests have been performed on horizontal samples containing different microstructures produced with the sintering technology. The samples were attached to the heating block with soldering. As a result of the experiments, boiling curves were obtained, describing the relationship between the dissipated heat flux and the superheat values for each specimen. A considerable augmentation of heat flux has been recorded for the meshed surfaces in relation to the smooth reference surface without any coating. Generally, the highest enhancement was recorded for the low superheat values. The presented test results have been discussed and then compared with selected correlations available in literature for nucleate boiling heat transfer on microstructure coated surfaces.