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The evaluation, visualization of environmental data from long-term monitoring, and making them accessible in a processed form in user-friendly interfaces on the Internet are important tasks of our time. The pollution of groundwater resources in settlements is a global phenomenon, the mitigation of which requires a number of environmental measures. In this study, water quality changes following the construction of a sewerage network were examined in the course of long-term monitoring between 2013 and 2022, during which 40 municipal groundwater wells were regularly sampled. Classifying the monitoring data into pollution categories based on water quality index (WQI) and degree of contamination index (Cd), a high degree of contamination was found in the period before the installation of the sewerage network (2014), as the majority of the wells were classified as contaminated and heavily contaminated. In the monitoring period following the installation of the sewerage network, a significant positive change was found in the case of most of the water chemical parameters tested (EC, NH4+, NO2−, NO3−, PO43−). Based on interpolated maps, it was found that an increasing part of the area shows satisfactory or good water quality. This was confirmed by the discriminant analysis as well, as it is possible to determine with an accuracy of 80.4% whether the given sample originates from the period before or after the installation of the sewerage network based on the given water chemical parameters. However, 8 years after setting up the sewerage network, the concentration of inorganic nitrogen forms and organic matter remains high, indicating that the accumulated pollutants in the area are still present. To understand the dynamics of purification processes, additional, long-term monitoring is necessary. Making these data available to members of the society can contribute to appropriate environmental measures and strategies. [ABSTRACT FROM AUTHOR]

[Objective] In order to effectively improve the processing quality of sugar beet monogerm seeds pelleting and explore the cleaning process of monogerm seeds, provide theoretical reference for seed pelleting of sugar beet monogerm. [Methods] By setting different test parameters, the effects of original seed size classification, grinding times, grinding conditions, specific gravity screening and water selection on the quality of sugar beet monogerm seeds were compared and analyzed. [Results] The graded treatment of original seeds could improve the uniformity of beet seed grain size and significantly improve the germination rate, compared with the original seeds without graded treatment (P<0.05). After screening and grading, the germination rate of the polished and regrinding seed was significantly higher (P < 0.05) than that of the original seeds (particle size 4.75-5.25 mm), and the germination rate of the grinding twice was the highest 89.30%, which was significantly higher than that of the regrinding once and other polished seeds (P < 0.05) The 1 000-grain weight and peeling rate of the seeds after grinding treatment were significantly different from that of the original unpolished seeds (P < 0.05) The screening results of different grinding conditions indicated that in the grinding intensity treatment, the germination potential and germination rate of different grinding intensity grades of 2.0-2.5 mm, 2.5-3.0 mm,3.0-3.5 mm were significantly different (P < 0.05), and the frequency of 35 Hz was significantly higher than that of 40 Hz (P < 0.05) The frequency of 35 Hz,time 3 min and 45 Hz and time 1 min had high germination rate, which was suitable for sugar beet monogerm seed grinding. The specific gravity screening results show that the germination rate and 1 000-grain weight of specific weight 2 were the highest, at 85.00% and 9.62 g. In them, the germination rate was significantly higher than that of other seeds except for specific gravity 3 (P < 0.05), and the 1 000-grain weight was significantly higher than that of other treatment (P < 0.05) In water selection test, it showed that the germination potential and germination rate after water selection+ back drying 18 h were the highest, with 91.25% and 92.75% respectively, which were significantly higher than other drying conditions (P < 0.05), and the water content at this time was 10%. [Conclusion] After a series of cleaning processes such as impurity removal, grading, polishing, specific gravity screening, and water selection, the germination rate of the original seeds of sugar beet monogerm seeds can be effectively improved, which is helpful for the promotion and application of sugar beet monogerm seeds pellet technology. [ABSTRACT FROM AUTHOR]

High quantity of slurries, kerf, are generated during ingot wafering and represent up to 40% of the silicon in weight. The highly pure silicon contained in kerf is contaminated with organics, metal impurities, water and an oxide layer. The recovery of the silicon could be an efficient way to reduce costs in the production of solar panels through material and energy savings. At high temperatures, organic contamination causes the formation of silicon carbide species that are difficult to segregate during kerf remelting into a pure silicon ingot. Also, during the fusion of silicon, temperatures up to 1500°C are reached and the mixture of silicon and water forms oxides and gases that reduce production yields and affect melting conditions. For these reason, purification and drying steps are required to ensure proper silicon raw material for remelting into ingots. So far, approaches using strong acidic or organic solvent are used to reduce contamination by organic compounds. In this study, more environmentally friendly processes were applied on authentic kerf waste to purify and dry silicon, to make it suitable as raw material for silicon ingot preparation. The amount of water and organic compounds were monitored along the process steps. Using aqueous oxidative processes in combination with filtration, kerf was cleaned and a total carbon reduction of at least 30% was observed. The control of humidity enables the convenient conditioning of purified kerf and effective drying reduced the moisture content to less than 5% wt.

Abstract Copper can be susceptible to corrosion in acidic cleaning solutions for desalination system, especially if the solution is highly concentrated or if the cleaning process involves extended exposure to the acid. In the current work, Aloe ferox Mill (AFM extract) can be used as a natural origin corrosion inhibitor for copper in 1.0 M HCl solution. The corrosion mitigation qualities of AFM extract were assessed by means of electrochemical, gravimetric, and surface examinations. AFM extract is a mixed-type inhibitor, based on polarization research findings. The inhibitory effectiveness of AFM extract rises with concentration, reaching its maximum level (93.3%) at 250 mg L–1. The inclusion of AFM extract raises the activation energy for the corrosion reaction from 7.15 kJ mol–1 (blank solution) to 28.6 kJ mol–1 (at 250 mg L–1 AFM extract).

Abstract Soot stain from diverse sources is the most common stain that stains historical paper documents found in libraries, museums, and storage facilities. It is believed to be one of the types of deterioration that arises from the contact between stains and paper sheets. Therefore, in the present work, the effectiveness of the synthesized hybrid nanogel consisting of carbopol and nanoparticles (NPs) of ZnO, TiO2, or Fe3O4, in low and high-viscosity forms, for eliminating soot stains from historical paper manuscripts was conducted. The prepared hybrid nanogels were characterized utilizing the TEM, AFM, XRD, DLS, and Zeta Potential techniques. Following preparation, the soot-stained paper samples were heated to 105 °C for 6 days, a process known as accelerated thermal aging. Surface morphology, mechanical properties and the color change of the paper samples were investigated. The prepared hybrid nanogel had a spherical shape with well-defined edges and uniform size, with an average particle diameter ranging from 30 to 35 nm. There was no significant NPs agglomeration seen, suggesting uniform dispersion in the carbopol matrix. Additionally, the prepared gels' crystal structure and phase purity were revealed by the XRD analysis results. Paper fibers were visible in some parts of the treated sample with TiO2/carbopol hybrid nanogel at high-viscosity before aging. Cleaning soot-stained paper samples using high-viscosity Fe3O4/carbopol hybrid nanogel is more successful than using low-viscosity nanogel. the sample treated with high-viscosity ZnONPs/carbopol hybrid nanogel produced the highest total color differences (ΔE) (26.17). The paper sample treated with high-viscosity ZnO/carbopol hybrid nanogel exhibited the maximum tensile strength (61.8 N/mm2) and elongation at break (1.174%). The evaluation of the paper samples both before and after the cleaning process revealed that, the treatment with high-viscosity ZnO/carbopol hybrid nanogel gave the best results in removing soot stains from stained paper samples.

Acrylic polymers were extensively used in past restoration practices, usually as consolidants or protecting agents. Their removal is often required because polymer coatings can improve some decay processes of stone substrates and, after ageing, may generate undesirable materials on the surface of artifacts. Therefore, the removal of old polymer coating from the surface of artifacts has become a common operation in the conservation of cultural heritage. As with other cleaning operations, it is a delicate process that may irreversibly damage the artifacts if not correctly carried out. The main aim of this study was to determine the appropriate cleaning procedure for efficiently removing old acrylic polymers (e.g., Paraloid B-72) from the surface of historical buildings. For this purpose, a polymer was applied to two different porous stone substrates (bio-calcarenite and arenaria stone). The hydrogel cleaning approach was used for the present study, as preliminary results suggested that it is the most promising polymer-removing method. The considered hydrogel (based on a semi-interpenetrating polymer network involving poly(2-hydroxyethyl methacrylate) and polyvinylpyrrolidone) was prepared and characterized using different techniques in order to assess the gel's properties, including the gel content, equilibrium water content, retention capability, hardness, Young's modulus, and morphology. After that, the hydrogel was loaded with appropriate amounts of nano-structured emulsions (NSEs) containing a surfactant (EcoSufTM), organic solvents, and H2O, then applied onto the coated surfaces. Moreover, plain EcoSurfTM in a water emulsion (EcoSurf/H2O) was also used to understand the polymer-removing behavior of the surfactant without any organic solvent. A comparative study was carried out on artificially aged and unaged polymer-coated samples to better understand the cleaning effectiveness of the considered emulsions for removing decayed polymer coatings. The experimental results showed that the NSE-loaded hydrogel cleaning method was more effective than other common cleaning procedures (e.g., cellulose pulp method). In fact, only one cleaning step was enough to remove the polymeric material from the stone surfaces without affecting their original properties. [ABSTRACT FROM AUTHOR]

Soot stain from diverse sources is the most common stain that stains historical paper documents found in libraries, museums, and storage facilities. It is believed to be one of the types of deterioration that arises from the contact between stains and paper sheets. Therefore, in the present work, the effectiveness of the synthesized hybrid nanogel consisting of carbopol and nanoparticles (NPs) of ZnO, TiO2, or Fe3O4, in low and high-viscosity forms, for eliminating soot stains from historical paper manuscripts was conducted. The prepared hybrid nanogels were characterized utilizing the TEM, AFM, XRD, DLS, and Zeta Potential techniques. Following preparation, the soot-stained paper samples were heated to 105 °C for 6 days, a process known as accelerated thermal aging. Surface morphology, mechanical properties and the color change of the paper samples were investigated. The prepared hybrid nanogel had a spherical shape with well-defined edges and uniform size, with an average particle diameter ranging from 30 to 35 nm. There was no significant NPs agglomeration seen, suggesting uniform dispersion in the carbopol matrix. Additionally, the prepared gels' crystal structure and phase purity were revealed by the XRD analysis results. Paper fibers were visible in some parts of the treated sample with TiO2/carbopol hybrid nanogel at high-viscosity before aging. Cleaning soot-stained paper samples using high-viscosity Fe3O4/carbopol hybrid nanogel is more successful than using low-viscosity nanogel. the sample treated with high-viscosity ZnONPs/carbopol hybrid nanogel produced the highest total color differences (ΔE) (26.17). The paper sample treated with high-viscosity ZnO/carbopol hybrid nanogel exhibited the maximum tensile strength (61.8 N/mm2) and elongation at break (1.174%). The evaluation of the paper samples both before and after the cleaning process revealed that, the treatment with high-viscosity ZnO/carbopol hybrid nanogel gave the best results in removing soot stains from stained paper samples. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As the core component of a cold cathode lamp, the quality of the cold cathode electrode has a direct impact on the quality and lifespan of the lamp. In order to improve the quality of cold cathode lamps, this study conducted experimental research on the production process of cold cathode electrodes: (1) improving the tungsten rod cleaning process; (2) using oxygen free sintered glass beads. The experimental results demonstrate that these improvements can effectively improve the quality of the cold cathode electrode. [ABSTRACT FROM AUTHOR]

Cleaning is one of the most important, essential, and delicate operation which has to be handled by conservators before applying new materials to any substrates. In past decades, nanotechnology introduced new concepts and materials in the conservation field, which have been providing many advantageous performances, especially higher than older materials. As a result, the conservators have already started to use nanomaterials in the cleaning processes of artifacts. Taking into consideration this new approach, our study has focused on using nano-structured emulsions (NSE) as smart cleaning materials for removing polymer coatings (e.g., acrylic polymers). For this purpose, Paraloid B-72 was applied on three different substrates (glass, Lecce stone, and Arenaria stone) and cleaning was performed by a specific nano-structured emulsion (NSE) based on an eco-friendly surfactant (EcoSurf) and two organic solvents in different proportions. In order to better understand the interaction of surfactant and organic solvents with polymer coating, plain EcoSurf in water was also used for comparison. In this study, the decay process of the considered polymer was also deeply studied, because it directly affects the cleaning effectiveness. Coated specimens of the different substrates were artificially aged and examined by different techniques: chromatic variations and contact angle measurements, optical microscopy, FTIR, and SEM-EDS. This material characterization process is important to understand the colour, morphology, and micro-structural difference, and the changes of hydrophobic behaviour as well as chemical composition of Paraloid B-72 polymer due to different ageing processes. After that, substrates coated with both unaged and aged polymer were cleaned by NSE according to the direct-contact procedure and cellulose pulp method. Preliminary analyses suggested that the direct-contact cleaning performed by nano-emulsion (i.e., NSE) induced a complete removal of the acrylic polymer, despite that this method is not recommended for the artifacts and can be hardly applicable in real cases. On the other hand, experimental results showed that satisfactory cleaning of stone substrates can be obtained by using NSE/the cellulose pulp system. [ABSTRACT FROM AUTHOR]

Anodic bonding is a reliable packaging method for MEMS devices, and the surface properties of the wafer directly affect the bonding efficiency. Therefore, the surface treatment of the wafer to be bonded is necessary. Herein, the effects of three different surface cleaning processes (degreasing, piranha solution and RCA solution) on the wafer surface were investigated by atomic force microscopy, scanning electron microscopy, infrared spectroscopy, and anodic bonding experiments. The analysis showed that during the anodic bonding of the RCA solution-cleaned wafer and Pyrex glass, the bonding interface was more closely attached, and the best surface properties were obtained. The anodic bonding experiments of the wafer and Pyrex glass showed that the bonding current increased with the applied voltage, and the bonding time decreased accordingly. This was most evident in the case of RCA cleaning. The SEM images showed that as the bonding voltage increased, the bonding interface became more uniform without obvious voids. Due to the influence of the strong electric field and temperature field, an irreversible chemical reaction occurred at the bonding interface, which formed a bonding layer that was key to successful bonding. [ABSTRACT FROM AUTHOR]

A Y2O3 coating was prepared using the atmospheric plasma spraying (APS) technique. On exposing the coating to CF4/O2/Ar plasma, a fluorine contamination layer (YOxFy) was formed, which was the main cause of process drift and contamination particle generation on the APS–Y2O3 coating surface. To remove the YOxFy layer on the coating surface, a piranha solution, which is a mixture of sulfuric acid and hydrogen peroxide, was employed for cleaning. The piranha solution was found to be an excellent medium for removing the YOxFy layer. The amount of contamination particle generated could be reduced by approximately 37% after cleaning with a 3:1 piranha solution compared with before cleaning. [ABSTRACT FROM AUTHOR]

A mathematical model has been developed that describes the process of purification of vegetable oils using physical methods. The obtained mathematical model determines the mode of operation of the main parameters of the machine for the purification of vegetable oils, depending on the dispersed composition of the impurities and the type of vegetable oils. Based on the developed mathematical model, the recommended rotor speed and the time to remove the impurities in a centrifuge for the maximum removal of the suspended particles from different types of vegetable oils can be calculated. The response surfaces show the combined effect of the particle density and the rotational speed of the centrifuge's rotor on the impurity removal rate and the impurity removal time in sunflower and rapeseed oil. The obtained theoretical data can be used, in practice, in setting the basic parameters of the machine and selecting the centrifuge's different modes of operation with a periodic action in the purification of various vegetable oils.

In the light-activated work-holding devices, hardened adhesive residues on the fixture plate need to be removed to make it available for the subsequent work holding. There are several ways to remove the cured adhesive from the gripper, such as laser-based degradation, and softening and removing with high temperature pressured water wash. These processes are associated with the generation of carbon black, affecting transparency which compromises the efficiency of the light-activated device. A novel peripheral grinding-based cleaning process has been developed to strip the adhesive from the fixture plate. The present research is aimed to analyze the effect of variation in grinding parameters, viz., spindle speed, feed, depth of cut, and the grain size of the grinding wheel on the temperature of the adhesive being ground and cleaning of the adhesive-filled channel. Aggressive values of grinding parameters are selected to achieve the desired removal of adhesive, putting a step towards sustainability. Moreover, a comprehensive investigation of the temperature of the grinding zone and the grinding wheel is made by inspecting the effective cleaning of the cured adhesive-filled channel. Higher values of spindle speed (11.57 m/s) and feed (0.406 mm/rev) resulted in an improved, cleaned surface of the ground adhesive-filled channel. Moreover, the grinding wheel with a more prominent grain size (46/Ø 0.35 mm) and porosity was proved to be more effective in the cleaning process by reducing and maintaining the grinding temperature (~52 °C) of the adhesive-filled channel. [ABSTRACT FROM AUTHOR]

Copyright of Eastern-European Journal of Enterprise Technologies is the property of PC TECHNOLOGY CENTER and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to evaluate the phenomena in a contiguous interface between a wet polyvinyl alcohol (PVA) sponge and various wafers during a chemical mechanical polishing cleaning process, the torques of a rolling wet PVA sponge were measured when it was pressed against various materials. In particular, we sought to determine how the torques between two materials were affected by surface free energy, which is a surface condition parameter consisting of hydrogen bonding component and dispersive component. The results of our investigation suggest that increasing the rotational speed of a wet PVA sponge decreases some of the torques generated due to hydrogen bonding component interactions. [ABSTRACT FROM AUTHOR]

Object: This research addresses different issues related to the ventilation and the aerosol concentration present in a metal additive manufacturing facility using Laser Powder Bed Fusion (L-PBF) machine. Performing air monitoring requires quantifying the emissions potentially generated in the different areas and during the different L-PBF process phases. A practical Indoor Air Quality (IAQ) assessment protocol is addressed in this research questioning the type of emissions to measure, and the way to collect them. Methods: As a measurement strategy for the airborne particles lower than 700 nm, real-time metrology discmini instruments were used (Testo, 1 L.min−1, Forbach, France). The particle number concentration was assessed during three operations: (i) before cleaning the room where the L-PBF machine is located, (ii) during the cleaning phase of the room, and (iii) after the cleaning phase. Results: Without ventilation and without human activity, the background concentration level in the additive manufacturing facility was 5.103 #/cm3 either before or after cleaning. With ventilation and without human activity, the background concentration level was decreased to 4.103 #/cm3 before cleaning, and increased to 1.5.104 #/cm3 after cleaning. Besides, human activity leads to an increase in the number of suspended particles, since they passed from 5.103 #/cm3 to 1.9.104 #/cm3. Finally, a value of 105 #/cm3 was recorded on the operator during the cleaning phase and clearly, show peaks of particle number concentration. Conclusion: It was found that the local ventilation plays a role in the resuspension of particles from surfaces. Indeed, particles deposited on the floor are a source of exposure and hence the need for a clean room. The result section reinforces the necessity of wearing individual protective equipment during the maintenance and cleaning operations of a facility including L-PBF machine. [ABSTRACT FROM AUTHOR]

A mathematical model has been developed that describes the process of purification of vegetable oils using physical methods. The obtained mathematical model determines the mode of operation of the main parameters of the machine for the purification of vegetable oils, depending on the dispersed composition of the impurities and the type of vegetable oils. Based on the developed mathematical model, the recommended rotor speed and the time to remove the impurities in a centrifuge for the maximum removal of the suspended particles from different types of vegetable oils can be calculated. The response surfaces show the combined effect of the particle density and the rotational speed of the centrifuge's rotor on the impurity removal rate and the impurity removal time in sunflower and rapeseed oil. The obtained theoretical data can be used, in practice, in setting the basic parameters of the machine and selecting the centrifuge's different modes of operation with a periodic action in the purification of various vegetable oils. [ABSTRACT FROM AUTHOR]

An experimental study is conducted on the use of a normally impinging turbulent water jet (with the Reynolds number of R e ≈ 11 800), for cleaning thick layers of a Newtonian fluid and two viscoplastic fluids (i.e. , transparent Carbopol solutions). The layer thickness is larger than the jet radius. Non-intrusive techniques are used to track the geometrical features of the cleaning process in real time. The effects of layer thickness and fluid yield stress on removal behavior, including cleaning radius, cavity radius, and angle, are investigated. A yield stress promotes the initial formation of a blister rather than a cavity, and the rate of removal decreases with increasing layer thickness and yield stress. A relation is presented for the growth of the cavity radius, which fits our experimental observations well. A comparative analysis of submerged and impinging jets reveals, for the first time, the role of air entrainment in the process, with bubble characteristics such as trajectory, size distribution (diameter), and velocity being determined by the yield stress. • Exploring cleaning of thick viscoplastic layers using turbulent jets. • Investigating effects of yield stress and thickness of layers on cleaning behavior. • Quantifying cleaning behavior via cleaning radius, cavity radius and contact angle. • Developing simple models to predict key cleaning characteristics. • Unveiling the role of air entrainment in cleaning process. [ABSTRACT FROM AUTHOR]

While moving along the milk-conducting systems in a milking machine, milk is in contact with the inner surface whose area exceeds 20 m2. That leads to the formation of protein-fat biofilms of contamination, which are a nutrient medium for the development of microorganisms. With insufficiently effective cleaning of these contaminants, in the periods between milking, the number of microflorae located in milk-conducting systems increases by tens of thousands of times. When cleaned with ineffective cleaning agents, mineral elements from milk are adsorbed on the surface of a protein-fat bio-film, which are subsequently compacted, changed, and converted into milk stone. In this case, the technical implementation of milk conducting systems is of critical importance. It has been established that a milk line made from any material is better cleaned with a hot washing solution than a cold one. Thus, with an increase in the temperature of a washing solution from 60 °C to 85 °C, the cleaning time of the milk line is reduced from 9.5 minutes to 1.5 minutes, or by 6 times. It was established that during the washing phase of a milk line there is a significant decrease in the temperature of the washing solution (≈30 %), which reduces the effectiveness of cleaning the parts of the system. Therefore, there is a need to maintain the solution temperature throughout the entire cleaning process. It is proved that the specific energy of adhesion of pollution in water is 2 times higher than that in a washing solution. With an increase in the temperature of the solution for every 10 °C, the decrease in the specific energy of pollution adhesion is on average 13 %. With an increase in the period after the end of milking before washing the milk line, the specific energy of its purification increases. The study reported here could lead improve the productivity of milking machines and the quality of the resulting product. That involves designing milking and dairy equipment from innovative materials. [ABSTRACT FROM AUTHOR]

1Modern cluster tools tend to clean the chambers each time a specified number of wafers have been processed. Such cleaning processes are intended to reduce the quality risk due to the residual chemicals within the chambers. When such cleaning processes are introduced, the conventional scheduling methods for cluster tools, such as the swap sequence for dual-armed cluster tools, are no longer effective. Therefore, we examine a cyclic scheduling problem for a dual-armed cluster tool that performs cleaning processes periodically. We first identify sufficient conditions for which the conventional backward and swap sequences give the minimum cycle time. We then develop a systematic way of generating all feasible robot task sequences, for which the cycle times can be computed. However, the number of feasible robot task sequences increases too fast to be enumerated as the cleaning cycle and the number of process steps increase. To address the complexity problem, we propose two heuristic scheduling strategies and compare them with the conventional scheduling methods and the lower bound of each schedule, respectively, to verify their effectiveness experimentally. [ABSTRACT FROM AUTHOR]

Edible Bird's Nest (EBN) has been used as a health modulator for many centuries. Nutrient degradation in EBN always happen during cleaning process due to many factors such as temperature and long soaking time in water. The present study attempts to find the difference between unclean and cleaned EBN in their amino acid composition. A total of 65 EBN samples were collected directly from swiftlet premises in 13 states of Malaysia to ensure the coverage of geographical location differences. A standardized cleaning method had been adapted from the industry to clean the collected EBN sample in the lab. Then it was analysed for amino acids composition. After that OPLS-DA multivariate model was used to discriminate the unclean and cleaned EBN on 18 types of amino acids composition. The model was robust with classification and predictive ability of 76.1% and 64.5%, respectively. The model was further validated with sample blind test and 100% of the sample was accurately fall into their respective cluster, unclean and cleaned EBN. The findings suggest that three major amino acids with the highest VIP value were Aspartic acid, Methionine and Glutamic acid and proposed as the marker for discriminating the unclean and cleaned EBN. [ABSTRACT FROM AUTHOR]

• The optimal cleaning process combined inline-HF/HNO 3 and batch-polish solution. • Cells with low I Rev 0.15A have good optical property after optimal cleaning process. • Developed wraparound model addressed the principle of cleaning process. • A pilot efficiency >23.53% of TOPCon cells cleaned with optimal process. The use of tunnel oxide passivated contact (TOPCon) solar cells on the n-type Cz-Si wafers has thus far attracted more interest in the photovoltaics (PV) industry. However, the cells encounter the problems of wraparound appearance and edge leakage current. These phenomena can result in the decrease in the optical and electrical performance of the cells, such as open circuit voltage (V oc), short-circuit current density (J sc), and fill factor (FF). In this work, several cleaning processes were adopted to resolve the problems for cells. The wraparound model and experimental results indicated that an effective cleaning process was carried out and revealed the correlation between the removal of the wraparound film and the edge junction layer on the surface of wafers. The optimized cleaning process did not destroy the boron-doping layer on the front side, and the poly-Si layer on the rear side. This process combined an inline etching process of HF/HNO 3 treatment and a batch-type etching process of the KOH/polish additives solution treatment, which could effectively solve the problems associated with optical properties and achieve a low reversed-biased junction leakage current (I Rev) 0.15 A at −14.5 V. After optimization of the rear surface recombination and the boron diffusion processes, industrial-type TOPCon cells at the present pilot line were obtained with the efficiency (E ff), V oc , J sc and FF of 23.53%, 706 mV, 40.65 mA/cm2 and 82.02%, respectively. This optimized cleaning process could be applied and promoted in the PV industry. [ABSTRACT FROM AUTHOR]

In the present study, changes in groundwater quality are assessed after the construction of the sewerage network, based on 3 water quality indices. Sampling took place before (2013) and after (2017, 2018, 2019) the establishment of a sewerage network in 2014. In the pre-sewerage period, strong pollution of the groundwater was detected. A total of 90% of the groundwater wells according to the water quality status by Brown, 70% of the wells according to the contamination index Cd by Rapant, and 80% of the wells according to the Canadian Council of Ministers of the Environmental Water Quality Index were categorized in the “polluted” or “heavily polluted” categories. After the establishment of the sewerage, significant changes were observed. In 2017, the number of wells in category 5 indicating the most contaminated samples decreased significantly for all three indices, while the number of samples in categories “good” and “acceptable” increased. Discriminant analysis was performed to determine if pre- and post-sewerage samples could be separated. A total of 75.6% of the cross-validated values were successfully categorized into the appropriate category, which indicates a significant difference between pre- and post-sewerage. Based on point and interpolated maps, it was established that in 2013, all three indices showed the highest pollution in the inner and southern parts of the settlement, while the northern areas of the settlement were less polluted. Based on the indices, it was determined that the process of groundwater purification in the settlement has started, although it will continue for years to come. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate the influence of the barley cleaning process in relation to physical properties. The knowledge of the range of changes in the physical parameters of processed material and their mutual relationships is required for the design and implementation of various technological processes. In this study were compared the input and output commodities in the primary postharvest cleaning process of undesirable components—occurring as admixtures of fine and coarse barley impurities as well as the barley component itself. An efficient cleaning process ensuring barley grain quality is a basic step in beer production. Therefore, seven bred varieties of brewing barley (Malz, Sebastian, Francin, KWS Irina1, KWS Irina2, Bojos, and Laudis) were tested for the qualitative assessment of the cleaning process. Physical parameters such as granulometry, bulk and tapped density, angle of repose, internal and wall friction angle, and flow functions were determined for all samples. In order to identify whether the barley variety or the sample cleaning significantly influences the determined physical properties, two‐way ANOVA was applied. The results imply that barley cleaning had the main influence on wall friction angle, while the barley variety had a significant effect on effective internal friction. Moreover, the mechanical postharvest cleaning process reduces the overall wall friction. [ABSTRACT FROM AUTHOR]

This study evaluated the organic residues of milk fouling using fluorescence and confocal laser scanning microscopy. The inorganic content was analyzed with energy-dispersive X-ray spectroscopy, complemented with inductively coupled plasma optical emission spectrometry. These techniques were applied to evaluate milk fouling cleanliness using an alkaline product and an enzymatic formulation based on protease and amylase. The results showed that the efficiency of enzymatic cleaning was 87.1% when it was evaluated at 55°C for 30 min, and with a medium of pH 8.5. No difference was found from the efficacy in eliminating dairy fouling observed for the chemical cleaning (86.9%). The fluorescence microscopy proved useful for determining the organic solid components in the outer layer of the dairy fouling. The fouling spatial disposition in 3 dimensions, obtained by confocal laser scanning microscopy, showed that it was formed of 51.3% sugars, 9.3% fats, and 39.4% proteins, with the enzymatic cleaning of these compounds being homogeneous, compared with chemical cleaning. The protein and lipid contents were in the surface layer, whereas sugars were located in the innermost part that contributes to the Maillard reaction during fouling formation. After enzymatic cleaning, the reduction in the concentration of Ca and P was 71.61 and 74.67%, respectively, compared with fouling intact. Thus, enzymatic cleaning, without the accumulation of Na from chemical cleaning, leaves 1.5 times less mineral than chemical cleaning. Knowing the content and structure of fouling in the industry helps to formulate better products to achieve proper levels of cleanliness. Additionally, studying the cleaning residues helps to avoid problems of cross-contamination between batches or subsequent microbial growths (biofilms) on surfaces with residues. [ABSTRACT FROM AUTHOR]

An analysis has been made of existing studies in which liquid food products are processed by ultrasonic waves. It was established experimental setup with an ultrasonic generator for the purification of sunflower oil under the effect of the ultrasonic field. A methodology has been developed to determine the optimal frequency of ultrasound, the ultrasound emission power and the time of purification of vegetable oils. The technological parameters of the process of purifying sunflower oil by ultrasonic treatment were determined and experimental process studies were carried out. A basis of experimental data has been developed in the studies of the sunflower oil purification process. In this study the main focus is to determine the technological parameters of the ultrasonic treatment of the raw materials by conducting experimental modeling of the process of cleaning sunflower oil under the action of the ultrasonic field. [ABSTRACT FROM AUTHOR]