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1
Han, M. Y., H. J. Ahn, M. S. Shin, and S. R. Kim. "The effect of divalent metal ions on the zeta potential of bubbles." Water Science and Technology 50, no. 8 (October 1, 2004): 49–56. http://dx.doi.org/10.2166/wst.2004.0486.
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Micro-bubbles are used in electro-flotation (EF) and dissolved air flotation (DAF) for particle separation. The efficiency of these flotation processes depends on the collision of bubble and particle and the collision efficiency is affected by certain parameters with respect to the size and zeta potential of bubble and particle. Therefore, it is necessary to monitor not only the zeta potential of the particle, but also that of the bubble. Gas bubbles are reported to be generally negatively charged in water. In this paper, we report a study performed to measure the zeta potential of bubbles in solutions containing divalent metals and find factors which can produce positively charged bubbles. Calcium and magnesium ions were selected as divalent metal ions because natural water normally contains an appreciable quantity of them. It was found that bubbles are negatively charged in CaCl2 solutions whereas, under certain conditions, they become positively charged in MgCl2. Charge reversal of bubbles was observed above 10-2 M Mg, especially above pH 9. A probable principle that explained the charge reversal could be a combined mechanism with both specific adsorption of hydroxylated species and formation of hydroxide precipitates. Creating solution conditions that can produce positively charged bubbles in flotation methods might make it possible to remove particles using lesser amounts of coagulant or even none at all.
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Amy, G., T. U. Kim, J. Yoon, C. Bellona, J. Drewes, J. Pellegrino, and T. Heberer. "Removal of micropollutants by NF/RO membranes." Water Supply 5, no. 5 (December 1, 2005): 25–33. http://dx.doi.org/10.2166/ws.2005.0035.
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Organic and inorganic micropollutants are rejected by high-pressure membranes, nanofiltration (NF) and reverse osmosis (RO), primarily as a consequence of solute–membrane interactions. These interactions include steric and electrostatic effects that depend on compound properties (e.g., molecular weight (MW) and ionic charge) and membrane properties (e.g., molecular weight cutoff (MWCO) and surface charge (zeta potential)), with the added influence of membrane operating conditions (e.g., recovery). This paper summarizes the rejection trends by several NF and RO membranes for a wide range of organic micropollutants based on hydrophobicity/hydrophilicity (octanol-water partition coefficient, KOW) and charge (neutral or negative), and a more narrow range of inorganic micropollutants in the form of oxyanions (chromate, arsenate and perchlorate) of varying MW and charge. While RO provided greater rejections of micropollutants than NF, observed NF rejections were, in many cases, significant. For oxyanions, rejection was mainly influenced by ionic charge and MW. RO properties generally had little influence while MWCO and zeta potential were both significantly influential for NF. For organic micropollutants, with exception of RO versus NF classifications, membrane properties were less influential than compound properties with greater rejections generally observed with increasing MW, KOW, and (negative) charge.
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Jefferson, Bruce, Emma L. Sharp, Emma Goslan, Rita Henderson, and Simon A. Parsons. "Application of charge measurement to water treatment processes." Water Supply 4, no. 5-6 (December 1, 2004): 49–56. http://dx.doi.org/10.2166/ws.2004.0092.
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The measurement of surface charge has long been proposed a convenient way to optimise coagulant dosage in water treatment processes. In the UK there has been a renewed interest in the use of charge measurement in the form of both zeta potential and streaming current for controlling coagulation and filtration processes. This paper review current knowledge on the factors effecting charge measurement and using data collected from a sampling survey of 12 UK water treatment works identified windows of optimum charge for sedimentation, flotation and filtration processes.
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Gao, Lihui, Shulei Li, and Yongtian Wang. "Effect of different pH coking wastewater on adsorption of coking coal." Water Science and Technology 73, no. 3 (October 19, 2015): 582–87. http://dx.doi.org/10.2166/wst.2015.528.
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H2SO4 has an effect on the sorption of organic contaminants by coking coal (CC) in wastewater. This paper focused on the effect of pH on the removal of chemical oxygen demand (COD), phenols and ammonia. UV-vis spectra, Fourier transform infrared spectra, zeta potential and Brunauer, Emmett and Teller (BET) analysis were investigated to characterize the changes of CC properties and coking wastewater (CW) at different pH values. The results showed that the COD and phenol removal efficiencies increased with decreasing pH value, while the ammonia removal efficiency was decreased gradually. A new transmittance band in the region of 340–600 cm−1 was observed in UV-vis spectra of CW in acidic condition. The absolute value of the zeta potential as the solution was gradually increasing with the increasing of pH value. Surface area and total pore volume of CC which was immersed in acidic solutions measured by BET were much higher than that of raw CC. CC has a greater adsorption capacity to organic pollution in the acidic solution mainly by van der Waals forces and hydrogen bonding.
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Sharp, E. L., S. A. Parson, and B. Jefferson. "Coagulation of NOM: linking character to treatment." Water Science and Technology 53, no. 7 (March 1, 2006): 67–76. http://dx.doi.org/10.2166/wst.2006.209.
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The paper presents an overview and discussion on the link between natural organic matter (NOM) character and its treatability by coagulation. Trials were conducted on a series of bench scale and pilot plant trials on three source waters: two from UK moorland catchments and one from a US snow melt source. Overall the work demonstrates the importance of the polarity balance and the charge density of the NOM contained within the source water. The hydrophobic content controls the coagulant demand such that variation in the demand between sources or sampling periods can be accounted for by changes in the hydrophobic content and its charge density. The raw water hydrophilic content, and specifically the nonacid fraction, provides a useful indicator of the achievable residual. Analysis of coagulation performance revealed a clear relationship between zeta potential and residual DOC. For each source an operational zeta potential range exists within which the residual concentration is optimal. Comparison of the ranges achieved during each trial demonstrated that a communal range between −10 and +3 mV exist for all waters thus providing a useful guide range for operational control.
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Kuhn, Bernd, Michal Talik, Torsten Fischer, Xiuru Fan, Yukinori Yamamoto, and Jennifer Lopez Barrilao. "Science and Technology of High Performance Ferritic (HiperFer) Stainless Steels." Metals 10, no. 4 (April 2, 2020): 463. http://dx.doi.org/10.3390/met10040463.
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Future, flexible thermal energy conversion systems require new, demand-optimized high-performance materials. The High performance Ferritic (HiperFer) stainless steels, under development at the Institute of Microstructure and Properties of Materials (IEK-2) at Forschungszentrum Jülich GmbH in Germany, provide a balanced combination of fatigue, creep and corrosion resistance at reasonable price. This paper outlines the scientific background of alloy performance development, which resulted in an age-hardening ferritic, stainless steel grade. Furthermore, technological properties are addressed and the potential concerning application is estimated by benchmarking versus conventional state of the art materials.
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Curvers, Daan, Hans Saveyn, Wim Van den Broeck, Patrick Van Oostveldt, and Paul Van der Meeren. "A method for visualising polyelectrolyte distribution after polyelectrolyte conditioning of a biotic sludge." Water Science and Technology 63, no. 6 (March 1, 2011): 1303–8. http://dx.doi.org/10.2166/wst.2011.375.
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Charge neutralisation is an important mechanism in (polyelectrolyte) conditioning of biotic sludges and required for efficient sludge dewatering. Based on results from streaming potential and zeta potential measurements, it has been suggested that charge neutralisation is more complete on the outside of the sludge flocs than on the inside. This paper discusses the development of a technique for assessing the spatial distribution of polyelectrolyte (PE) within sludge flocs. After flocculation with a fluorescently labelled PE, fluorescence microscopy can be used to visualise the distribution of the PE in the sludge flocs. Preliminary results indicate that the PE can penetrate relatively deep into the sludge flocs (and flocculi). Inhomogeneity in the PE distribution arises from differences in exposure to PE in different regions, and from differences in the affinity of the PE for different substances.
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Jefferson, B., P. Jarvis, E. Sharp, S. Wilson, and S. A. Parsons. "Flocs through the looking glass." Water Science and Technology 50, no. 12 (December 1, 2004): 47–54. http://dx.doi.org/10.2166/wst.2004.0694.
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The paper describes the investigation of how the make up of raw water influences the physical properties of flocculated suspensions. The work focuses on the properties of four characteristic organic fractions separated as a function of their hydrophobicity. Mesoscale data indicates that the hydrophobic fractions dominate the make up of the water and are the most easily removed. Microscale and nanoscale data reveals that the fulvic acid fraction (FAF) generates statistically smaller and more compact flocs than those formed by the other fractions and the hydrophilic fractions form the most internally open and dendritic structures. The FAF fraction was also seen to dominate the zeta potential response of the raw water.
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Trzcinski, Antoine Prandota, Lily Ganda, Chinagarn Kunacheva, Dong Qing Zhang, Li Leonard Lin, Guihe Tao, Yingjie Lee, and Wun Jern Ng. "Characterization and biodegradability of sludge from a high rate A-stage contact tank and B-stage membrane bioreactor of a pilot-scale AB system treating municipal wastewaters." Water Science and Technology 74, no. 7 (July 23, 2016): 1716–25. http://dx.doi.org/10.2166/wst.2016.346.
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In light of global warming mitigation efforts, increasing sludge disposal costs, and need for reduction in the carbon footprint of wastewater treatment plants, innovation in treatment technology has been tailored towards energy self-sufficiency. The AB process is a promising technology for achieving maximal energy recovery from wastewaters with minimum energy expenditure and therefore inherently reducing excess sludge production. Characterization of this novel sludge and its comparison with the more conventional B-stage sludge are necessary for a deeper understanding of AB treatment process design. This paper presents a case study of a pilot-scale AB system treating municipal wastewaters as well as a bio- (biochemical methane potential and adenosine tri-phosphate analysis) and physico-chemical properties (chemical oxygen demand, sludge volume index, dewaterability, calorific value, zeta potential and particle size distribution) comparison of the organic-rich A-stage against the B-stage activated sludge. Compared to the B-sludge, the A-sludge yielded 1.4 to 4.9 times more methane throughout the 62-week operation.
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Kavanagh, Yvonne, Dina Brazil, Gina Noonan, David Dowling, Ronan Bree, Edel Healy, Moira Maguire, et al. "Studying Student Experience of Technology Enhanced Assessment Methods (TEAM) in Science and Health in Ireland." MRS Advances 3, no. 12 (2018): 631–36. http://dx.doi.org/10.1557/adv.2017.627.
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ABSTRACTThis is a cross institution project involving four Institutes of Technology in Ireland. The objective of this project is to assess the use of technology to enhance the assessment of laboratory sessions in Science and Health. In science, health and engineering, the laboratory sessions are at the core of the learning process for skill development. These laboratory sessions focus on the skills acquisition. The Irish Institute of Technology sector, in particular, develops these skills and considers them essential for ‘professionally ready’ graduates. In terms of student progression and retention, the assessment structure has been identified as having a significant impact on student engagement.The Technology Enhanced Assessment Methods (TEAM) project led by Dundalk Institute of Technology and partnering with Institute of Technology Sligo, Athlone Institute of Technology and Institute of Technology Carlow is exploring the potential offered by digital technologies to address these concerns. It aims to develop a framework for applying the principles of effective assessment and feedback to practical assessment. The TEAM project also aims to facilitate dialogue among stakeholders about what it is we want student to learn in laboratory sessions and how our assessment can facilitate this. A peer network of discipline-specific academics and students in the Science and Health field has been established across all four Institutes. As the network focuses on authentic skills assessment in all core modules, including physics and chemistry, the best practice from this project will inform future assessment procedures across laboratory sessions and may be considered for application within a Science and Materials Engineering context.Assessing the skills acquired in this environment takes many forms. Using student and stakeholder feedback along with an extensive literature review of the area, the team identified key technologies that cut across science and health disciplines, with the potential to influence and enable the learning process. The emphasis was on developing a powerful learning environment approach to enable students to deepen their learning through engagement with the process. The areas identified are: (i) Pre-practical preparation (videos and quizzes), (ii) Electronic laboratory notebooks and ePortfolios, (iii) Digital Feedback technologies and (iv) Rubrics).This paper describes the student experience and perceptions of the adoption of digital technology in science practical assessments. It also describes the process involved in setting up the pilot structure and it presents the initial results from the student survey.
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Mkhize, Zimbili, Pule Silent Seboletswe, Hugues Kamdem Paumo, Pone Kamdem Boniface, and Lebogang Maureen Katata-Seru. "Enhanced Antioxidant Efficacy of Nano-Encapsulated Protorhus Longifolia Methanol Extract Stabilized with Eudragit." International Journal of Nanoscience 20, no. 02 (January 25, 2021): 2150017. http://dx.doi.org/10.1142/s0219581x21500174.
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This study describes the synthesis of Protorhus longifolia methanolic leaf extract-loaded Eudragit nanoparticles (NPs) and assessment of their antioxidant activity comparative to the free methanolic extract. The latter was also analyzed for its total phenolic content (TPC) and total flavonoid content (TFC). The extract-loaded NPs were obtained through the emulsification solvent evaporation process and systematically characterized using the dynamic light scattering, entrapment efficiency, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The antioxidant power was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing ability of plasma (FRAP) in vitro model systems. Screening of the different classes of secondary metabolites was carried out through chemical reaction tests. Identification of the potential antioxidants was performed using the gas chromatography-mass spectrometry (GC-MS) technique and the database of National Institute Standard and Technology (NIST). The characterization techniques showed spherical-like particles having an average size of 150[Formula: see text]nm and zeta potential of [Formula: see text]22[Formula: see text]mV. The percentage of entrapped methanolic extract was determined to be 83%. The antioxidant assay demonstrated that this methodology persuaded an efficient concentration-dependent potential. This study indicates that nanoformulation of the Protorhus longifolia extracts leads to a suitable system for the enhancement of antioxidant activity. The appraisal of other pharmacological activities of the nano-encapsulated Protorhus longifolia methanol extract is under process.
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Erkan, Hanife Sari, and Guleda Onkal Engin. "The investigation of paper mill industry wastewater treatment and activated sludge properties in a submerged membrane bioreactor." Water Science and Technology 76, no. 7 (June 16, 2017): 1715–25. http://dx.doi.org/10.2166/wst.2017.351.
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The paper mill industry produces high amounts of wastewater and, for this reason, stringent discharge limits are applied for sustainable reclamation and reuse of paper mill industry wastewater in many countries. Submerged membrane bioreactor (sMBR) systems can create new opportunities to eliminate dissolved substances present in paper mill wastewater including. In this study, a sMBR was operated for the treatment of paper mill industry wastewater at 35 h of hydraulic retention time (HRT) and 40 d of sludge retention time (SRT). The chemical oxygen demand (COD), NH3-N and total phosphorus (TP) removal efficiencies were found to be 98%, 92.99% and 96.36%. The results demonstrated that sMBR was a suitable treatment for the removal of organic matter and nutrients for treating paper mill wastewater except for the problem of calcium accumulation. During the experimental studies, it was noted that the inorganic fraction of the sludge increased as a result of calcium accumulation in the reactor and increased membrane fouling was observed on the membrane surface due to the calcification problem encountered. The properties of the sludge, such as extracellular polymeric substances (EPS) and soluble microbial products (SMP), relative hydrophobicity, zeta potential and floc size distribution were also monitored. According to the obtained results, the total EPS was found to be 43.93 mg/gMLSS and the average total SMP rejection by the membrane was determined as 66.2%.
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XU, LEBO, JEREMY MYERS, and PETER HART. "How to use alum with cationic dispersed rosin size." May 2016 15, no. 5 (June 1, 2016): 331–35. http://dx.doi.org/10.32964/tj15.5.331.
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Retention of cationic dispersed rosin size was studied via turbidity measurements on stock filtrate with different alum and dispersed rosin size dosages. Stock charge characteristics were analyzed using both an analysis of charge demand determined via a streaming current detector and an evaluation of zeta potential of the fibers by streaming potential measurement. The results indicated that an optimum amount of alum existed such that good sizing retention was maintained throughout a wide range of dispersed rosin size dosages. However, when an excessive amount of alum was used and fines and colloidal particles were transitioned from anionic to cationic, the cationic size retention was reduced. Laboratory results were confirmed with a paper machine trial. All data suggested that a stock charge study was necessary to identify optimal alum dosage for a cationic dispersed rosin sizing program.
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Bastos, C. R. A., H. Otta, L. P. M. Poppe, M. F. B. Silva, and M. G. F. Dantas. "Evaluation of Groundwater Potential Pollution Sources in the State of São Paulo, Brazil." Water Science and Technology 24, no. 11 (December 1, 1991): 221–28. http://dx.doi.org/10.2166/wst.1991.0355.
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The objective of this work is to present the methodology used in the project “Vulnerability Mapping and Groundwater Pollution Risk in the State of São Paulo, Brazil”, implemented by the DAEE, CETESB and Institute of Geology, and intended to be a risk assessment procedure to evaluate the threat of groundwater quality deterioration using existing data. Such method is based on the interaction between the natural aquifer vulnerability and an imposed contaminant load generated by human activities, and aims to identify critical areas to prioritize the adoption of control measures and more intensive quality monitoring. This paper describes the principles used in the assessment of the contaminant load generated by industries, solid waste disposal and mining activities in the State. More than 500 industries were identified as important groundwater potential pollution sources, and a criterion of ranking their capability to generate contaminant loads to the aquifer was|established.
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Henderson, R., E. Sharp, P. Jarvis, S. Parsons, and B. Jefferson. "Identifying the linkage between particle characteristics and understanding coagulation performance." Water Supply 6, no. 1 (January 1, 2006): 31–38. http://dx.doi.org/10.2166/ws.2006.005.
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The coagulation/flocculation process is important for particle separation in water treatment. However, difficulties arise when coagulation is not optimised for the dominant particle. This paper investigates the surface characteristics and floc properties of three common systems– natural organic matter (NOM), algae and clay – in order to aid understanding of the coagulation/flocculation process. It was demonstrated that charge density and specific surface area are important parameters with respect to coagulant demand for charge neutralisation for all systems. However, extracellular organic matter (EOM) affected the coagulant demand of algae to the extent that it appears that the presence of EOM could dominate the coagulation process. Controlling the zeta potential of the systems prompted improved particle aggregation and hence removal efficiency in all cases. Floc growth profiles revealed that algal flocs required five times the flocculation period to reach a steady-state floc size compared to NOM and clay and on exposure to increased shear were much weaker. Despite similarities between algae and NOM in terms of organic content and coagulant demand, the fact that algae is a dynamic, biological system as opposed to an inert system creates numerous problems for the coagulation/flocculation process.
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Sun, Qianshu, Shuang Zhao, Yubo Yan, Wenlin Jia, and Weihua Yang. "Parameter optimization and mechanism research of enhanced coagulation treatment for Yuquan River water." Water Supply 20, no. 3 (March 3, 2020): 1072–82. http://dx.doi.org/10.2166/ws.2020.030.
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Abstract As one of the drinking water sources for Xuzhou city, Yuquan River has been polluted seriously in recent years. In this paper, enhanced coagulation technology was selected and various parameters (coagulant species, dosage, solution pH and coagulant aid species) were optimized for Yuquan River water treatment. Turbidity and UV254 removal rate were calculated to assess coagulation efficiencies, and meanwhile floc generation kinetics, zeta potential and scanning electron microscope (SEM) spectra were measured to study the coagulation mechanism. Results indicated that the coagulation effect of polyaluminium chloride (PAC) on Yuquan River water was better than that of aluminium sulphate (AS), and its optimal dosage was 20 mg/L. Flocs produced by PAC also exhibited larger size and faster growth velocity than those of AS. Moreover, the applicable initial pH range for Yuquan River was 6.0–9.0, and the optimal coagulation efficiency was observed at pH 7.0. When PAC or AS was selected as coagulant, the application of sodium alginate (SA) could improve turbidity and UV254 removal due to its adsorption bridging role. In addition, coagulation efficiency could be enhanced in an AS coagulation system when polyacrylamide (PAM) was dosed as coagulant aid.
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Soo, J. W., L. C. Abdullah, S. N. A. M. Jamil, and A. A. Adeyi. "Sequestration of p-nitrophenol from liquid phase by poly(acrylonitrile-co-acrylic acid) containing thioamide group." Water Science and Technology 84, no. 1 (May 25, 2021): 237–50. http://dx.doi.org/10.2166/wst.2021.204.
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Abstract In this paper, the adsorptive performance of synthesized thiourea (TU) modified poly(acrylonitrile-co-acrylic acid) (TU-P(AN-co-AA)) polymeric adsorbent for capturing p-nitrophenol (PNP) from aqueous solution was investigated. TU-P(AN-co-AA) was synthesized via the redox polymerization method with acrylonitrile (AN) and acrylic acid (AA) as the monomers, then modified chemically with thiourea (TU). Characterization analysis with Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), elemental microanalysis for CHNS, zeta potential measurement, Brunauer–Emmett–Teller (BET) surface analysis and thermal analyses were carried out to determine the morphology and physico-chemical properties of the synthesized polymer. The characterization results indicated successful surface modification of polymer with TU. The performance of TU-P(AN-co-AA) for the removal of PNP was investigated under various experimental parameters (adsorbent dosage, initial adsorbate concentration, contact time and temperature). The results demonstrated that the Freundlich isotherm model and pseudo-second-order kinetic model best described the equilibrium and kinetic data, respectively. Thermodynamic studies showed that the uptake of PNP by TU-P(AN-co-AA) was spontaneous and exothermic in nature. The results of the regeneration studies suggested that the TU-P(AN-co-AA) polymer is a reusable adsorbent with great potential for removing PNP from wastewater.
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Nobaharan, Khatereh, Sepideh Bagheri Novair, Behnam Asgari Lajayer, and Eric van Hullebusch. "Phosphorus Removal from Wastewater: The Potential Use of Biochar and the Key Controlling Factors." Water 13, no. 4 (February 17, 2021): 517. http://dx.doi.org/10.3390/w13040517.
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In recent years, a large volume of literature has been published regarding the removal of phosphorus (P) from wastewater. Various sorbing materials, such as metal oxides and hydroxides, carbonates and hydroxides of calcium (Ca) and magnesium (Mg), hydrotalcite, activated carbon, anion exchange resins, industrial solid wastes and organic solid wastes, have been suggested for P removal. Many of these sorbents are expensive and/or may cause some environmental problems. In contrast, biochar, as an economical and environmentally friendly sorbing material, has received much attention in recent years and has been used as a novel sorbent for the removal of different organic and inorganic pollutants. Biochar is a type of sustainable carbonaceous material that is produced from the thermal treatment of agricultural organic residues and other organic waste streams under oxygen free conditions. This paper reviews the potential use of biochar and the key controlling factors affecting P removal from wastewater. The ability of biochar to remove P from wastewater depends on its physical and chemical properties. Some of the most important physicochemical properties of biochar (structural characteristics, electrical conductivity (EC), mineral composition, pH, zeta potential, cation exchange capacity (CEC) and anion exchange capacity (AEC)) are affected by the feedstock type as well as temperature of pyrolysis and the P sorption capacity is highly dependent on these properties. The P removal is also affected by the water matrix chemistry, such as the presence of competing ions and bulk pH conditions. Finally, several recommendations for future research have been proposed to facilitate and enhance the environmental efficiency of biochar application.
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Cheng, Benai, Jie Wang, Wenbin Liu, Zhao Cui, Fanghua Bi, Hui Jia, and Hongwei Zhang. "Membrane fouling reduction in a cost-effective integrated system of microbial fuel cell and membrane bioreactor." Water Science and Technology 76, no. 3 (May 5, 2017): 653–61. http://dx.doi.org/10.2166/wst.2017.250.
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Microbial fuel cells (MFC) and membrane bioreactors (MBR) are promising technologies for wastewater treatment. However, both of them have some drawbacks and application limitations. A cost-effective hybrid system (EMBR) integrating MFC with MBR was evaluated in terms of treatment performance and membrane fouling. In this paper, two electric field directions with a membrane module in the middle were applied to explore the mechanism of membrane fouling mitigation in EMBRs. In both configurations of EMBRs, microbial activity and degradation ability of activated sludge for chemical oxygen demand and NH4+−N removals could be enhanced compared with those for the controlled MBR. In addition, the irreversible resistance significantly decreased, especially in the EMBR(−) with a longer operation time. Furthermore, two critical factors, namely enhanced bioflocculation and electrophoresis forces, were compared based on key parameters (zeta potential, particle size distribution and extracellular polymeric substances). The electrophoresis forces made a greater contribution to fouling alleviation than that conducted by the enhanced bioflocculation. The results suggested that EMBR, as a promising wastewater treatment technology, improved effluent quality and reduced energy consumption.
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Wang, Fei, Hongmei Lü, Xiujun Wang, Bo Jing, Ming Duan, Yan Xiong, and Shenwen Fang. "Preparation of a selective flocculant for treatment of oily wastewater produced from polymer flooding and its flocculant mechanism." Water Science and Technology 79, no. 9 (May 1, 2019): 1648–56. http://dx.doi.org/10.2166/wst.2019.154.
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Abstract There are residual polymers in the oily wastewater produced from polymer flooding (OWPF); keeping the residual polymer in the water during the flocculation is meaningful and challenging. In this paper, a selective flocculant (denoted as PDC10) which can remove the oil while keeping partially hydrolyzed polyacrylamide (HPAM) in water was prepared by copolymerization of decyl two methyl vinylbenzyl ammonium chloride (C10MVBA) and dimethyl aminopropyl methacryamide (DMAPMA). By using oil removal and HPAM retention as evaluation indexes, the synthesis condition of PDC10 was optimized. The optimum PDC10 exhibited oil removal of 98.0% and HPAM retention of 80.5%. Its HPAM retention is much higher than that of a regular cationic flocculant. Measurements of zeta potential, interfacial tension, interfacial dilational modulus and a dual polarization interferometry (DPI) test were carried out for investigating the flocculation mechanism of PDC10. The mechanism of PDC10 was that it can bridge and flocculate oil droplets by electrostatic interaction and hydrophobic interaction. It also preferred to distribute at the interface, and its interaction with HPAM in bulk water was weak, which confirms its selective flocculation properties.
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TEKKAYA, ERMAN, MICHAEL TROMPETER, and WERNER HOMBERG. "INNOVATIVE FORMING TECHNOLOGY AS A KEY FOR THE EFFECTIVE MANUFACTURING OF LIGHTWEIGHT STRUCTURES." Journal of Advanced Manufacturing Systems 07, no. 01 (June 2008): 37–40. http://dx.doi.org/10.1142/s0219686708001061.
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Current tends in car body or rail traffic engineering aim at the realization of modern lightweight structures. In this context, demanding technological and economical requirements like the use of high strength materials, the forming of very complex geometries, and the reduction of costs, particularly with regard to low volume production, must be achieved. Novel approaches in the field of sheet metal hydroforming are able to overcome existing limitations of conventional forming technologies and feature a higher potential for an effective manufacturing of lightweight structures. This paper shows the current research work at the Institute of Forming Technology and Lightweight Construction (IUL) in the face of sheet metal hydroforming with a special focus on the design of tool systems.
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Ranjan, Rajiv, Lokendra Kumar, and P. C. Sabumon. "Process performance and reuse potential of a decentralized wastewater treatment system." Water Science and Technology 80, no. 11 (December 1, 2019): 2079–90. http://dx.doi.org/10.2166/wst.2020.046.
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Abstract The paper describes briefly the process performance and the reuse potential of a laboratory scale wastewater treatment system. The treatment involves enhanced primary treatment of Vellore Institute of Technology (VIT) campus sewage using ferric chloride as a coagulant, anaerobic digestion of coagulated organics, and biofilm aerobic process. The treated effluent after disinfection (using sunlight and chlorine) was used for irrigation of Tagetes erecta (marigold) plants and the plant growth parameters were evaluated for a life span of 3 months. In the primary treatment, an optimum ferric chloride dose of 30 mg/L could remove turbidity, chemical oxygen demand (COD), biochemical oxygen demand (BOD), and bacterial count (Escherichia coli) of 69%, 60%, 77%, and 55%, respectively. The coagulated organics could digest in a 25 L anaerobic reactor effectively with methane content in biogas varied between 50 and 60% and enhanced volatile suspended solids (VSS) reduction up to 70%. Sunlight based photo-oxidation followed chlorine disinfection saved 50% of the chlorine dose required for disinfection and treated effluent was fit for reuse. The results of growth parameters for Tagetes erecta plants indicate that anaerobically digested sludge is an excellent soil conditioner cum nutrient supplier. The results of this study exhibit a promising reuse potential of a decentralized wastewater treatment system and needs to be promoted for field scale applications.
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Religa, P., and A. Kowalik-Klimczak. "Effect of interaction between anionic surfactants and poly(piperazine-amide) nanofiltration membranes used for chromium(III) recovery from saline solution." Water Science and Technology 72, no. 10 (August 1, 2015): 1803–9. http://dx.doi.org/10.2166/wst.2015.406.
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The effect of the anionic surfactant on the permeation properties of the nanofiltration (NF) membranes used for chromium(III) recovery from saline solution at low pH have been presented in this paper. The membrane surface layer performance periodically modified by sodium dodecyl sulphate (SDS) solution has been studied with measurements of zeta potential, atomic force microscopy (AFM) and permeability coefficient of tested membranes. It was found that the membrane surface layer modification by SDS caused a substantial reduction in the possibility of separation of loose NF membrane characterized by a high density of positively charged groups activating under the effect of the low pH of the saline solutions (HL membrane). On the other hand, in the case of dense NF membranes characterized by a strong negatively charged surface (DL membrane) constituting used the SDS improves the separation of chloride and chromium(III) ions. In this case, the surfactant solution also provides a high membrane permeability coefficient behavior over a long period of use. DL membrane modification by SDS allowed both to retain the stable membrane working for a long period and to limit the frequency of the chemical cleaning of this membrane.
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Zhang, Peiliang, Shujie Jia, Xiaohong Zhang, Jing Li, Shan Lu, and Pengfu Li. "Hydrophobicity and iron coagulation of extracellular polymeric substance from colonial Microcystis." Water Science and Technology 80, no. 6 (September 15, 2019): 1174–84. http://dx.doi.org/10.2166/wst.2019.360.
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Abstract The bloom-forming cyanobacterium Microcystis occurs mainly as colonial aggregates under the natural conditions. This paper investigated the hydrophobicity and iron coagulation of extracellular polymeric substances (EPSs) from colonial Microcystis in order to understand the impact of EPS on the water treatment process. The higher contents of dissolved EPS (dEPS) and bound EPS (bEPS, mucilaginous matrix around the cells), lower dEPS/bEPS ratio and greater negative zeta potential of bEPS and dEPS were found in colonial Microcystis compared with unicellular Microcystis. XAD resin fractionation analysis indicated that the hydrophobicity could be ranked in an order as follows: bEPS > dEPS > dissolved extracellular organic matter (dEOM) for all the Microcystis strains. Correlation analysis showed that there was a statistically significant correlation between the amounts of carbohydrate and dissolved organic carbon in the hydrophobic fraction of EOM (dEOM, dEPS and bEPS), indicating that the hydrophobicity of Microcystis EOM might be related to carbohydrate. The coagulation experiment showed that for each colonial Microcystis strain, the removal efficiency of bEPS was higher than that of dEPS within the pH range from 3 to 10. The implications of the EPS characteristics were further discussed with respect to water treatment.
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Kloosterman, Ate, Anna Mapes, Zeno Geradts, Erwin van Eijk, Carola Koper, Jorrit van den Berg, Saskia Verheij, Marcel van der Steen, and Arian van Asten. "The interface between forensic science and technology: how technology could cause a paradigm shift in the role of forensic institutes in the criminal justice system." Philosophical Transactions of the Royal Society B: Biological Sciences 370, no. 1674 (August 5, 2015): 20140264. http://dx.doi.org/10.1098/rstb.2014.0264.
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In this paper, the importance of modern technology in forensic investigations is discussed. Recent technological developments are creating new possibilities to perform robust scientific measurements and studies outside the controlled laboratory environment. The benefits of real-time, on-site forensic investigations are manifold and such technology has the potential to strongly increase the speed and efficacy of the criminal justice system. However, such benefits are only realized when quality can be guaranteed at all times and findings can be used as forensic evidence in court. At the Netherlands Forensic Institute, innovation efforts are currently undertaken to develop integrated forensic platform solutions that allow for the forensic investigation of human biological traces, the chemical identification of illicit drugs and the study of large amounts of digital evidence. These platforms enable field investigations, yield robust and validated evidence and allow for forensic intelligence and targeted use of expert capacity at the forensic institutes. This technological revolution in forensic science could ultimately lead to a paradigm shift in which a new role of the forensic expert emerges as developer and custodian of integrated forensic platforms.
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Medina, Oscar E., Yira Hurtado, Cristina Caro-Velez, Farid B. Cortés, Masoud Riazi, Sergio H. Lopera, and Camilo A. Franco. "Improvement of Steam Injection Processes Through Nanotechnology: An Approach through in Situ Upgrading and Foam Injection." Energies 12, no. 24 (December 6, 2019): 4633. http://dx.doi.org/10.3390/en12244633.
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This study aims to evaluate a high-performance nanocatalyst for upgrading of extra-heavy crude oil recovery and at the same time evaluate the capacity of foams generated with a nanofluid to improve the sweeping efficiency through a continuous steam injection process at reservoir conditions. CeO2±δ nanoparticles functionalized with mass fractions of 0.89% and 1.1% of NiO and PdO, respectively, were employed to assist the technology and achieve the oil upgrading. In addition, silica nanoparticles grafted with a mass fraction of 12% polyethylene glycol were used as an additive to improve the stability of an alpha-olefin sulphonate-based foam. The nanofluid formulation for the in situ upgrading process was carried out through thermogravimetric analysis and measurements of zeta potential during eight days to find the best concentration of nanoparticles and surfactant, respectively. The displacement test was carried out in different stages, including, (i) basic characterization, (ii) steam injection in the absence of nanofluids, (iii) steam injection after soaking with nanofluid for in situ upgrading, (iv) N2 injection, and (v) steam injection after foaming nanofluid. Increase in the oil recovery of 8.8%, 3%, and 5.5% are obtained for the technology assisted by the nanocatalyst-based nanofluid, after the nitrogen injection, and subsequent to the thermal foam injection, respectively. Analytical methods showed that the oil viscosity was reduced 79%, 77%, and 31%, in each case. Regarding the asphaltene content, with the presence of the nanocatalyst, it decreased from 28.7% up to 12.9%. Also, the American Petroleum Institute (API) gravity values increased by up to 47%. It was observed that the crude oil produced after the foam injection was of higher quality than the crude oil without treatment, indicating that the thermal foam leads to a better swept of the porous medium containing upgraded oil.
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Hirata, R. C. A., C. R. A. Bastos, G. A. Rocha, D. C. Gomes, and M. A. Iritani. "Groundwater Pollution Risk and Vulnerability Map of the State of São Paulo, Brazil." Water Science and Technology 24, no. 11 (December 1, 1991): 159–69. http://dx.doi.org/10.2166/wst.1991.0348.
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Aiming to provide a global diagnosis of the actual threat of pollution to the most important aquifers of the State of São Paulo, Brasil, due to its intensive industrialization and agriculture, three government institutions -the Instituto Geologico (Geological Institute), the CETESB (Environmental Sanitary Technology Company) and the DAEE (Water and Eleotrical Energy Department) - carried out a regional survey to define the aquifers' vulnerability to pollution and for recording and ranking the potential contaminant sources. This paper describes the results of this survey, excluding the metropolitan area of the city of São Paulo. More than 500 industries were recorded and ranked according to their low, moderate or high potential contaminant load for impacting groundwater. Thirty - one aquifer units were defined and a 1:500.000 scale vulnerability map was produced. Critical areas were defined and recommended as being priority sites for the adoption of control measures.
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Lindzey, Laura E., Lucas H. Beem, Duncan A. Young, Enrica Quartini, Donald D. Blankenship, Choon-Ki Lee, Won Sang Lee, Jong Ik Lee, and Joohan Lee. "Aerogeophysical characterization of an active subglacial lake system in the David Glacier catchment, Antarctica." Cryosphere 14, no. 7 (July 15, 2020): 2217–33. http://dx.doi.org/10.5194/tc-14-2217-2020.
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Abstract. In the 2016–2017 austral summer, the University of Texas Institute for Geophysics (UTIG) and the Korea Polar Research Institute (KOPRI) collaborated to perform a helicopter-based radar and laser altimeter survey of lower David Glacier with the goals of characterizing the subglacial water distribution that supports a system of active subglacial lakes and informing the site selection for a potential subglacial access drilling project. This survey overlaps with and expands upon an earlier survey of the Drygalski Ice Tongue and the David Glacier grounding zone from 2011 and 2012 to create a 5 km resolution survey extending 200 km upstream from the grounding zone. The surveyed region covers two active subglacial lakes and includes reflights of ICESat ground tracks that extend the surface elevation record in the region. This is one of the most extensive aerogeophysical surveys of an active lake system and provides higher-resolution boundary conditions and basal characterizations that will enable process studies of these features. This paper introduces a new helicopter-mounted ice-penetrating radar and laser altimetry system, notes a discrepancy between the original surface-elevation-derived lake outlines and locations of possible water collection based on basal geometry and hydraulic potential, and presents radar-based observations of basal conditions that are inconsistent with large collections of ponded water despite laser altimetry showing that the hypothesized active lakes are at a highstand.
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Muhmood, Luckman, Anna Semykina, Masanori Iwase, and Seshadri Seetharaman. "Some Novel Studies of Thermodynamics, Kinetics and Transport Phenomena in Slags." High Temperature Materials and Processes 31, no. 4-5 (October 30, 2012): 351–58. http://dx.doi.org/10.1515/htmp-2012-0067.
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AbstractThe following paper revolves around the research work conducted in collaboration during Professor Iwase's brief visits to the Materials Process Science Division at Royal Institute of Technology, Stockholm. The paper focuses on the thermodynamic aspects of CaO–FeO–SiO2 and CaO–FeO–SiO2–MnO slag oxidation in air and sulfur transport through CaO–Al2O3–SiO2 slag. Thermodynamics of slag oxidation in air opens potential new areas in terms of focus on effective recovery of iron oxide from slag. The slag transport studies are of fundamental nature and focuses on a novel technique to calculate the diffusion of species through slag by analyzing its corresponding concentration in the metal phase.
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Fang, Binbin, Yubo Yan, Yang Yang, Fenglian Wang, Zhen Chu, Xiuyun Sun, Jiansheng Li, and Lianjun Wang. "Adsorption of Pb2+ from aqueous solution using spinel ferrite prepared from steel pickling sludge." Water Science and Technology 73, no. 5 (November 14, 2015): 1112–21. http://dx.doi.org/10.2166/wst.2015.580.
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In this paper, spinel ferrite with high crystallinity and high saturation magnetization was successfully prepared from steel pickling sludge by adding iron source and precipitator in the hydrothermal condition. The obtained spinel ferrite was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), vibrating sample magnetometer (VSM), and Zeta potential methods and investigated as an adsorbent for removal of Pb2+ from aqueous solution. Batch experiments were performed by varying the pH values, contact time, temperature and initial metal concentration. The result of pH impact showed that the adsorption of Pb2+ was a pH dependent process, and the pH 5.8 ± 0.2 was found to be the optimum condition. The achieved experimental data were analyzed with various kinetic and isotherm models. The kinetic studies revealed that Pb2+ adsorption onto spinel ferrite followed a pseudo-second order model, and the Langmuir isotherm model provided the perfect fit to the equilibrium experimental data. At different temperatures, the maximum Pb2+ adsorption capacities calculated from the Langmuir equation were in the range of 126.5–175.4 mg/g, which can be in competition with other adsorbents. The thermodynamic results showed that the spinel ferrite could spontaneously and endothermically adsorb Pb2+ from aqueous solution. The regeneration studies showed that spinel ferrite could be used five times (removal efficiency (%) >90%) by desorption with HNO3 reagent.
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Bernardová, I., K. Mrázak, and M. Škollová. "Development of the Pollution of the River Morava Evaluated from Zoobenthic Communities." Water Science and Technology 29, no. 3 (February 1, 1994): 29–35. http://dx.doi.org/10.2166/wst.1994.0055.
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To obtain a more detailed picture of the water quality changes in river longitudinal profiles, an original biological monitoring system has been developed by the Water Research Institute (WRI) in Brno. The system is based on the exact selection of representative macrozoobenthic sampling points. A precise taxonomic identification and statistical evaluation create the basis for documentation of the present water quality and consequently for a water quality simulation model. The biological monitoring system enables information from basic chemical monitoring to be enhanced, and constitutes an eco-engineering tool for the central and regional control of the water quality. A potential cost reduction, when compared to classical modelling techniques, is a benefit which cannot be ignored. The system described is applied in the watershed of the river Morava as given in this paper, as well as for the whole Czech Republic.
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Jadczyszyn, Jan, and Marek Zieliński. "ASSESSMENT OF FARMS FROM HIGH NATURE VALUE FARMLAND AREAS IN POLAND." Annals of the Polish Association of Agricultural and Agribusiness Economists XXII, no. 3 (September 21, 2020): 108–18. http://dx.doi.org/10.5604/01.3001.0014.4013.
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The objective of the study is to assess production potential and structure and the economic situation of farms pursuing their activity in areas (in municipalities) with various saturation of High Nature Value farmland (HNVf) areas in Poland. The first part of the study presented a method of designating HNVf areas, designated by the Institute of Soil Science and Plant Cultivation National Research Institute (ISSPC-NRI) and the Institute of Agricultural and Food Economics National Research Institute (IAFE-NRI), in cooperation with the Institute of Technology and Life Sciences (ITLS), the Institute for Agricultural and Forest Environment of the Polish Academy of Sciences (IAFE-PAS), and the Polish Society for the Protection of Birds (PSPB) upon the request of the Ministry of Agriculture and Rural Development (MARD) and the European Commission (EC). HNVf areas have been designated on the basis of the adopted criteria of characteristics of extensive agriculture and high nature value areas. On the other hand, the second part of the paper consisted of the organisational and economic assessment of farms from municipalities with various saturation of HNVf areas in Poland, uninterruptedly keeping accounts for the Polish FADN in the years 2016-2018. It was determined that farms from municipalities with a high saturation of HNVf areas, when compared to farms from municipalities with a lower saturation of such areas, being a reference point, have a lower production potential of soils and achieve worse production results. They have, inter alia, a smaller UAA size, smaller labour inputs and smaller capital value, including machinery and equipment. In addition, they have lower income per 1 ha of UAA, which limits their development opportunities.
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KORATKAR, NIKHIL. "NANOSCALE FIELD IONIZATION SENSORS: A REVIEW." International Journal of Nanoscience 04, no. 05n06 (October 2005): 945–49. http://dx.doi.org/10.1142/s0219581x05003905.
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So far, one of the most promising applications of nanoscale science and technology has been in the area of field emission. The electric field amplification effects associated with sharp nanostructure tips can be used to significantly reduce the emission voltages. Another equally promising area that also takes advantage of the field amplification effects is the area of field ionization. The extremely high electrical fields generated near the vicinity of sharp nanostructure tips can be used to ionize chemical or biological species at a fraction of the voltage of a traditional ionizer. In this article we review two of the very first reported papers related to nanoscale field ionization published by our group at the Rensselaer Polytechnic Institute. The first paper describes a carbon nanotube gas ionizer, which shows potential for gas sensing applications. The second paper describes an ultra low-power gas ionizer featuring β-phase Tungsten nanorod electrodes. We end with a review of the major challenges that must be overcome to develop nanoscale ionization sensors.
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Okoniewska, Monika, and Danuta Szumińska. "Changes in Potential Evaporation in the Years 1952–2018 in North-Western Poland in Terms of the Impact of Climatic Changes on Hydrological and Hydrochemical Conditions." Water 12, no. 3 (March 20, 2020): 877. http://dx.doi.org/10.3390/w12030877.
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The paper analyses changes in potential evaporation E0 (mm) in north-western Poland in the years 1952–2018. E0 (mm) has been calculated according to Ivanov’s formula based on the monthly values of air temperature (t, °C) and relative air humidity (f, %) for six weather stations of the Institute of Meteorology and Water Management. The data were collected using the Statistica software ver. 13 and the QGIS software ver. 3.80. The results indicate statistically significant trends in the increase of E0 during the period 1952–2018, and that it is particularly high during the spring and summer months, which should be associated with a statistically significant increase in air temperature and a decrease in relative humidity at all examined stations. The results also indicate an exceptionally high increase in evaporation since the end of the 20th century and in the 21st century, which reflects a potentially higher risk of permanent changes in hydrological conditions. The research results point to the major role of climatic factors in the often-dramatic decreases in water resources observed in the 21st century, particularly in lakes and small watercourses. The progressing reduction of water resources may cause permanent changes in physical and chemical conditions in waterbodies.
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Chen, Shuya, Yanping Shi, Xianyu Yang, Kunzhi Xie, and Jihua Cai. "Design and Evaluation of a Surfactant–Mixed Metal Hydroxide-Based Drilling Fluid for Maintaining Wellbore Stability in Coal Measure Strata." Energies 12, no. 10 (May 16, 2019): 1862. http://dx.doi.org/10.3390/en12101862.
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Co-exploitation of coal measure gases (coalbed gas, shale gas, and tight sandstone gas) puts a higher requirement on drilling fluids. Conventional drilling fluids have disadvantages, such as causing problems of borehole collapse, formation damage, and water blockage. This paper proposes a set of high inhibitive and low-damage drilling fluids that function by electrical inhibition and neutral wetting. Zeta potential results showed that the negative electrical property of Longtan coal in Bijie, Guizhou, can be reversed by organic mixed metal hydroxide (MMH) and the cationic surfactant alkyl trimethylammonium bromide (CS-5) from −3.63 mV to 19.75 mV and 47.25 mV, respectively. Based on the contact angle and Fourier Transform Infrared Spectroscopy (FT-IR) results, it can be concluded that chemical adsorption dominates between the Longmaxi shale and surfactants, and physical adsorption between the Longtan coal and surfactants. A compound surfactant formula (0.001 wt% CS-4 + 0.001 wt% CS-1 + 0.001 wt% CS-3), which could balance the wettability of the Longmaxi shale and the Longtan coal, making them both appear weakly hydrophilic simultaneously, was optimized. After being treated by the compound surfactants, the contact angles of the Longmaxi shale and the Longtan coal were 89° and 86°, respectively. Pressure transmission tests showed that the optimized combination of compound surfactants and inorganic MMH (MMH-1) could effectively reduce permeability of the Longmaxi shale and the Longtan coal, thus retarding pore pressure transmission in coal measure strata. Then, the proposed water-based drilling fluid (WBDF) system (4 wt% sodium bentonite + 1.5 wt% sodium carboxymethyl cellulose + 2 wt% lignite resin + 5 wt% potassium chloride + 3 wt%MMH-1 + 0.001 wt% CS-4 + 0.001 wt% CS-1 + 0.001 wt% CS-3) was evaluated based on parameters including rheology, American Petroleum Institute (API) filtration, electrical property, wettability, inhibition capability, reservoir protection characteristics, and anti-pollution performance. It had an API filtration of 7 mL, reservoir damage rate of 10%, moderate and acceptable viscosity, strong inhibition capability to coal measure strata rocks, good tolerance to inorganic pollutants and drilling cuttings, and environmentally friendly properties. It could meet wellbore stability and reservoir protection requirements in the co-exploitation of coal measure gases.
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Mena, Kristina D., and Suresh D. Pillai. "An approach for developing quantitative risk-based microbial standards for fresh produce." Journal of Water and Health 6, no. 3 (March 1, 2008): 359–64. http://dx.doi.org/10.2166/wh.2008.047.
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A key objective of the Good Agricultural Practices (GAP) program is to reduce the potential for produce to become contaminated with microbial pathogens, such as through irrigation water. Without microbial standards, however, it is impractical to decide whether there is a need to disinfect, a need to institute watershed protection programs, or a need to institute post-harvest disinfection regimes. To develop such standards, quantitative microbial risk assessments can be performed using pathogen monitoring data for produce. This paper presents an approach which can be used towards the application of a risk assessment framework to developing microbial standards for fresh produce. Risks of infection are estimated using typical monitoring data of Salmonella detected on carrots and assuming various scenarios of the likelihood of an individual consuming a contaminated serving of carrots in a given year. Estimated annual risks of infection range from 2.20 × 10−5 to 2.16 × 10−3, assuming 1% and 100% of an individual's carrot servings are contaminated, respectively. In addition, critical factors are identified which need to be incorporated in such a risk assessment approach as well as their impact on risk estimates to provide growers with benchmarks which may be targeted to reduce health risks.
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Brzezińska, Dorota. "Ventilation System Influence on Hydrogen Explosion Hazards in Industrial Lead-Acid Battery Rooms." Energies 11, no. 8 (August 10, 2018): 2086. http://dx.doi.org/10.3390/en11082086.
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When charging most types of industrial lead-acid batteries, hydrogen gas is emitted. A large number of batteries, especially in relatively small areas/enclosures, and in the absence of an adequate ventilation system, may create an explosion hazard. This paper describes full scale tests, which demonstrate conditions that can occur in a battery room in the event of a ventilation system breakdown. Over the course of the tests, full scale hydrogen emission experiments were performed to study emission time and flammable cloud formation according to the assumed emission velocity. On this basis, the characteristics of dispersion of hydrogen in the battery room were obtained. The CFD model Fire Dynamic Simulator created by National Institute of Standards and Technology (NIST) was used for confirmation that the lack of ventilation in a battery room can be the cause of an explosive atmosphere developing, and leading to, a potential huge explosive hazard. It was demonstrated that different ventilation systems provide battery rooms with varying efficiencies of hydrogen removal. The most effective type appeared to be natural ventilation, which proved more effective than mechanical means.
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Chen, Dong, Feng Li, Yingxin Gao, and Min Yang. "Pilot Performance of Chemical Demulsifier on the Demulsification of Produced Water from Polymer/Surfactant Flooding in the Xinjiang Oilfield." Water 10, no. 12 (December 18, 2018): 1874. http://dx.doi.org/10.3390/w10121874.
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Purification of produced water (PW) from polymer/surfactant flooding is a challenge for the petroleum industry due to the high emulsion stability. Demulsification using chemical demulsifiers has been expected to be an effective way to treat PW. In this paper, five cationic (branched quaternary ammonium chloride) and four nonionic (copolymer of propylene oxide and ethylene oxide) demulsifiers with different molecular weights were employed to test their respective demulsification performance in the treatment of PW from polymer/surfactant flooding. The cationic demulsifiers, in general, exhibited better performance than the nonionic ones and one cationic demulsifier (CP-1) exhibiting the best demulsification efficiency was further employed for a pilot experiment in the Xinjiang Oilfield. The oil content of PW could be successfully reduced from 128~7364 to less than 10 mg/L with a dosage of CP-1 for 350 mg/L and polyaluminum chloride (PAC, 30% w/w Al2O3) for 500 mg/L under ambient temperature (14~22 °C). At the same time, partially hydrolyzed polyacrylamide (HPAM) was removed from 176.9~177.1 to 2.8~3.9 mg/L while petroleum sulfonate was not removed too much (from 35.5~43.8 to 25.5~26.5 mg/L). The interfacial rheology analysis on simulated PW from HPAM/petroleum sulfonate flooding revealed that the addition of CP-1 led to a significant increase of the oil-water interfacial tension (from 7 to 15~20 mN/m) and zeta potential (from −32.5 to −19.7 mV). It was, thus, assumed that the decreased net charge on the dispersed oil droplets surface and weakened oil/water film due to the formation of complex between the cationic demulsifier and HPAM may have facilitated the destabilization of the emulsion. The result of this study is useful in better understanding the demulsification processes as well as selecting suitable demulsifiers in the treatment of PW from polymer/surfactant flooding.
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Patrick, J. Molly, Susan Murcott, and Jarvis Punsalan. "Coupling microbiological testing and sanitary surveys in drinking water quality programs: results from Capiz Province, Philippines." Journal of Water, Sanitation and Hygiene for Development 1, no. 2 (June 1, 2011): 124–35. http://dx.doi.org/10.2166/washdev.2011.033.
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Developing countries often struggle to conduct laboratory-based water quality testing programs due to a lack of financial and technical resources. However, inexpensive, accurate, field-based tests are being developed which have the potential to overcome this barrier. This paper provides the results of an initiative by the Provincial Health Office in Capiz, Philippines, to conduct a first-ever, provincial, microbiological water quality test program. The effort was a collaboration with students from Massachusetts Institute of Technology, which aimed to identify sources most at risk, to test field-based analytical methods against standard methods, and to make recommendations for improving supplies in the short and long term. The microbiological, chlorine residual, and sanitary survey results are described in this paper. The results showed that there was an increasing trend in water quality from ‘unimproved’ to treated and/or piped supplies, but that many ‘improved’ point sources were contaminated. Less than 20% of the samples tested for chlorine residual were above the World Health Organization guideline. Sanitary surveys identified potential sources of contamination and were used to recommend priorities for remedial action. The implications of this work for other resource-limited areas are that microbiological testing and sanitary surveys are two essential components to assessing water safety and they should both be consistently applied in drinking water quality test programs.
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Kelly, Ruth, Lorcan Sirr, and John Ratcliffe. "Futures thinking to achieve sustainable development at local level in Ireland." Foresight 6, no. 2 (April 1, 2004): 80–90. http://dx.doi.org/10.1108/14636680410537547.
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We are living in times of unprecedented global change and upheaval and over the next ten to 20 years governments, organisations and individuals will face increasing difficulties in an environment of growing complexity, heightened uncertainty and a quickening pace of change. The concept of sustainable development implies the reconciliation of long‐term socio‐economic development, environmental protection and quality of life; essentially it is concerned with the future. Unfortunately, the potential for linking “futures thinking” to debates about sustainable development at local and regional government levels is relatively undeveloped, particularly in Ireland. Responding to this challenge, The Futures Academy at Dublin Institute of Technology, Ireland, was established in January 2003 to provide both a research and consultancy forum for future‐proofing policies and strategies using the “prospective through scenarios” methodology. This paper describes the evolution of sustainable development in Ireland and the generic field of futures thinking, with particular focus on the prospective process which may assist key local policy makers and stakeholders move towards sustainable development for future generations in Ireland.
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Ma, Chao-Tsung. "System Planning of Grid-Connected Electric Vehicle Charging Stations and Key Technologies: A Review." Energies 12, no. 21 (November 4, 2019): 4201. http://dx.doi.org/10.3390/en12214201.
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The optimal planning of electric vehicle (EV) charging stations (ECSs) with advanced control algorithms is very important to accelerate the development of EVs, which is a promising solution to reduce carbon emissions of conventional internal combustion engine vehicles (ICEVs). The large and fluctuant load currents of ECSs can bring negative impacts to both EV-related power converters and power distribution systems if the energy flow is not regulated properly. Recent review papers related to EVs found in open literature have mainly focused on the design of power converter-based chargers and power interfaces, analyses of power quality (PQ) issues, the development of wireless charging techniques, etc. There is currently no review paper that focuses on key technologies in various system configurations, optimal energy management and advanced control issues in practical applications. To compensate for this insufficiency and provide timely research directions, this paper reviews 143 previously published papers related to the aforementioned topics in recent literature including 17 EV-related review papers found in Institute of Electrical and Electronics Engineers (IEEE)/Institution of Engineering and Technology (IET) (IEEE/IET) Electronic Library (IEL) and ScienceDirect OnSite (SDOS) databases. In this paper, existing system configurations, related design methods, algorithms and key technologies for ECSs are systematically reviewed. Based on discussions given in the reviewed papers, the most popular ECS configuration is a hybrid system design that integrates renewable energy (RE)-based power generation (REBPG), various energy storage systems (ESSs), and utility grids. It is noteworthy that the addition of an ESS with properly designed control algorithms can simultaneously buffer the fast, fluctuant power demand during charging, smooth the intermittent power generation of REBPG, and increase the overall efficiency and operating flexibility of ECSs. In addition, verifying the significance of the flexibility and possible profits that portable ESSs provide in ECS networks is a potential research theme in ECS fields, in which the potential applications of portable ESSs in the grid-tied ECSs are numerous and could cover a full technical spectrum.
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AL-Behadili, Hayder. "Classification Algorithms for Determining Handwritten Digit." Iraqi Journal for Electrical and Electronic Engineering 12, no. 1 (June 1, 2016): 96–102. http://dx.doi.org/10.37917/ijeee.12.1.10.
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Data-intensive science is a critical science paradigm that interferes with all other sciences. Data mining (DM) is a powerful and useful technology with wide potential users focusing on important meaningful patterns and discovers a new knowledge from a collected dataset. Any predictive task in DM uses some attribute to classify an unknown class. Classification algorithms are a class of prominent mathematical techniques in DM. Constructing a model is the core aspect of such algorithms. However, their performance highly depends on the algorithm behavior upon manipulating data. Focusing on binarazaition as an approach for preprocessing, this paper analysis and evaluates different classification algorithms when construct a model based on accuracy in the classification task. The Mixed National Institute of Standards and Technology (MNIST) handwritten digits dataset provided by Yann LeCun has been used in evaluation. The paper focuses on machine learning approaches for handwritten digits detection. Machine learning establishes classification methods, such as K-Nearest Neighbor(KNN), Decision Tree (DT), and Neural Networks (NN). Results showed that the knowledge-based method, i.e. NN algorithm, is more accurate in determining the digits as it reduces the error rate. The implication of this evaluation is providing essential insights for computer scientists and practitioners for choosing the suitable DM technique that fit with their data.
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Havas, M. "Biological effects of non-ionizing electromagnetic energy: A critical review of the reports by the US National Research Council and the US National Institute of Environmental Health Sciences as they relate to the broad realm of EMF bioeffects." Environmental Reviews 8, no. 3 (March 1, 2000): 173–253. http://dx.doi.org/10.1139/a00-004.
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Our dependence on electricity and our growing dependence on wireless telecommunication technology is causing this planet to be inundated with electromagnetic energy ranging in frequency from less than 60 Hz to greater than 2 GHz. Concerns expressed by the public, who live near power lines, cell phone antennas, or television and radio broadcast towers, have prompted two major reviews: one by the US National Research Council (NRC) and the other by the US National Institute of Environmental Health Science (NIEHS). Both of these documents deal with the biological and health effects primarily in a residential setting of extremely low frequency (ELF) or power frequency (50 and 60 Hz) fields. This paper critically evaluates the NRC and NIEHS documents. This evaluation includes both the content and the process leading to the final reports. It summarizes the information available on human exposure to electric and magnetic fields and identifies key biological markers and potential mechanisms that have been linked to electromagnetic exposure. It examines the conclusions of both documents in terms of the slightly broader realm associated with occupational exposure, non-power frequency fields, EMF hypersensitivity, and response of species other than humans. It presents some of the scientific controversy surrounding the question "Are low frequency electric and magnetic fields harmful?'' and examines the concepts of bias and consistency in data interpretation. This paper also attempts to place the discussions about technologically generated fields (technofields) into a much broader perspective, a perspective that includes naturally occurring geofields and biofields. Key words: leukemia, breast cancer, melatonin, calcium flux, extremely low frequency electromagnetic fields, radio frequency radiation.
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Dell’Acqua, Edoarda Corradi, Jaime Marin, and Eric Wright. "INTEGRATED ARCHITECTURAL AND ENGINEERING DESIGN STRATEGIES FOR A ZERO-ENERGY BUILDING: ILLINOIS INSTITUTE OF TECHNOLOGY’S DESIGN ENTRY FOR THE 2018 U.S. DEPARTMENT OF ENERGY RACE TO ZERO (SOLAR DECATHLON DESIGN CHALLENGE)." Journal of Green Building 16, no. 2 (March 1, 2021): 251–70. http://dx.doi.org/10.3992/jgb.16.2.251.
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ABSTRACT This paper describes the design of InterTech, a zero-energy mixed-use student residence hall, developed in 2018 by an interdisciplinary team of Illinois Institute of Technology (Illinois Tech) students for the U.S. Department of Energy Solar Decathlon Design Challenge, formerly known as Race to Zero. The main focus is the team’s integrated and iterative approach, which blended architectural design and engineering concepts and led to achieving the high-performance goal. InterTech aims to provide an innovative housing solution to Illinois Institute of Technology’s graduate students and their families. Located along State Street in between Illinois Tech’s main campus and downtown Chicago, it offers a mix of living options providing both independence and access to the campus and to the city. In addition to the residential program, the project includes a small grocery/cafe connected to an outdoor public plaza, and an underground garage. Energy modeling was introduced in the early design stages. The potential of on-site renewable energy generation defined the project’s target Energy Use Intensity (EUI) of 37 kBtu/sqft. Several passive and active strategies were implemented to reduce the building’s total energy needs and meet the target EUI. The implementation of energy conservation measures led to a 25% reduction of the building’s cooling load and a 33% reduction of the heating load. A design EUI of 28 kBtu/sqft was calculated, validating that this design met and exceeded the zero-energy goal.
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Budney, Alan J., Lisa A. Marsch, Will M. Aklin, Jacob T. Borodovsky, Mary F. Brunette, Andrew T. Campbell, Jesse Dallery, et al. "Workshop on the Development and Evaluation of Digital Therapeutics for Health Behavior Change: Science, Methods, and Projects." JMIR Mental Health 7, no. 2 (February 26, 2020): e16751. http://dx.doi.org/10.2196/16751.
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The health care field has integrated advances into digital technology at an accelerating pace to improve health behavior, health care delivery, and cost-effectiveness of care. The realm of behavioral science has embraced this evolution of digital health, allowing for an exciting roadmap for advancing care by addressing the many challenges to the field via technological innovations. Digital therapeutics offer the potential to extend the reach of effective interventions at reduced cost and patient burden and to increase the potency of existing interventions. Intervention models have included the use of digital tools as supplements to standard care models, as tools that can replace a portion of treatment as usual, or as stand-alone tools accessed outside of care settings or direct to the consumer. To advance the potential public health impact of this promising line of research, multiple areas warrant further development and investigation. The Center for Technology and Behavioral Health (CTBH), a P30 Center of Excellence supported by the National Institute on Drug Abuse at the National Institutes of Health, is an interdisciplinary research center at Dartmouth College focused on the goal of harnessing existing and emerging technologies to effectively develop and deliver evidence-based interventions for substance use and co-occurring disorders. The CTBH launched a series of workshops to encourage and expand multidisciplinary collaborations among Dartmouth scientists and international CTBH affiliates engaged in research related to digital technology and behavioral health (eg, addiction science, behavioral health intervention, technology development, computer science and engineering, digital security, health economics, and implementation science). This paper summarizes a workshop conducted on the Development and Evaluation of Digital Therapeutics for Behavior Change, which addressed (1) principles of behavior change, (2) methods of identifying and testing the underlying mechanisms of behavior change, (3) conceptual frameworks for optimizing applications for mental health and addictive behavior, and (4) the diversity of experimental methods and designs that are essential to the successful development and testing of digital therapeutics. Examples were presented of ongoing CTBH projects focused on identifying and improving the measurement of health behavior change mechanisms and the development and evaluation of digital therapeutics. In summary, the workshop showcased the myriad research targets that will be instrumental in promoting and accelerating progress in the field of digital health and health behavior change and illustrated how the CTBH provides a model of multidisciplinary leadership and collaboration that can facilitate innovative, science-based efforts to address the health behavior challenges afflicting our communities.
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Olasek, Krzysztof, Maciej Karczewski, Michal Lipian, Piotr Wiklak, and Krzysztof Józwik. "Wind tunnel experimental investigations of a diffuser augmented wind turbine model." International Journal of Numerical Methods for Heat & Fluid Flow 26, no. 7 (September 5, 2016): 2033–47. http://dx.doi.org/10.1108/hff-06-2015-0246.
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Purpose A solution to increase the energy production rate of the wind turbine is proposed by forcing more air to move through the turbine working section. This can be achieved by equipping the rotor with a diffusing channel ended with a brim (diffuser augmented wind turbine – DAWT). The purpose of this paper is to design an experimental stand and perform the measurements of velocity vector fields through the diffuser and power characteristic of the wind turbine. Design/methodology/approach The experiments were carried out in a small subsonic wind tunnel at the Institute of Turbomachinery, Lodz University of Technology. An experimental stand design process as well as measurement results are presented. Model size sensitivity study was performed at the beginning. The experimental campaign consisted of velocity measurements by means of particle image velocimetry (PIV) and pneumatic pitot probe as well as torque and rotational velocity measurements. Findings Characteristics (power coefficient vs tip speed ratio) of the bare and shrouded wind turbine were obtained. The results show an increase in the wind turbine power up to 70-75 per cent by shrouding the rotor with a diffuser. The mechanisms responsible for such a power increase were well explained by the PIV and pneumatic measurement results revealing the nature of the flow through the diffuser. Research limitations/implications Experimental stand for wind turbine rotor testing is of a preliminary character. Most optimal methodology for obtaining power characteristic should be determined now. Presented results can serve as good input for choice of stable and reliable control system of wind turbine operational parameters. Practical implications A 3 kW DAWT is being developed at the Institute of Turbomachinery, Lodz University of Technology. Aim of the study is to design a compact and smart wind turbine optimised for low wind speed conditions. Developed wind turbine has a potential to be used as an effective element within a net of distributed generation, e.g. for domestic use. Originality/value Research carried out is the continuation of theoretical study began in 1970s. It was also inspired by practical solutions proposed by Japanese researchers few years ago. Presented paper is the summary of work devoted to optimisation of the DAWT for wind conditions in the region. Original solution has been applied, e.g. for experimental stand design (3D printing application).
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Lim, S., S. Allabakash, B. Jang, and V. Chandrasekar. "Polarimetric Radar Signatures of a Rare Tornado Event over South Korea." Journal of Atmospheric and Oceanic Technology 35, no. 10 (October 2018): 1977–97. http://dx.doi.org/10.1175/jtech-d-18-0041.1.
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AbstractThe Korea Institute of Civil Engineering and Building Technology (KICT) made one of the first radar observations of a rare tornadic storm that occurred on 10 June 2014 in the Seoul metropolitan region, South Korea, using X-band dual-polarization radar. The tornado lasted for about 18 min, during which it destroyed about 20 greenhouses and injured several people. This tornado was rated at F0 on the Fujita scale. The KICT X-band dual-polarization radar was installed in the area northwest of Seoul to monitor storm development, measure rainfall, improve hazard mitigation, and disaster management. This paper presents the high-resolution (both spatial and temporal) polarimetric radar observations of the tornado, along with the radar parameters of reflectivity, differential reflectivity, Doppler velocity, and copolar correlation coefficient. The characteristic signatures of polarimetric variables, including the descending reflectivity core, weak echo hole, Doppler velocity couplet, and hook echo, are used to describe the tornado vortex and its development. In addition, the close range (about 5-km distance) observations of the hook echo show the high-resolution radar signatures of a weak echo region surrounded by high-reflectivity annular rings inside the tornado vortex. From development to dissipation, various finescale features are observed, including lofted tornadic debris and potential hail signatures. The high-resolution (close range) observations were also compared against low-resolution (long range) radar observations. The comparison shows that high-spatiotemporal, low-altitude, and close-range observations can be significantly advantageous for tornado detection and early warning.
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Sivam, Ashwin, Teresa Dieguez, Luís Pinto Ferreira, and F. J. G. Silva. "Key settings for successful Open Innovation Arena." Journal of Computational Design and Engineering 6, no. 4 (March 20, 2019): 507–15. http://dx.doi.org/10.1016/j.jcde.2019.03.005.
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Abstract The purpose of this paper is to examine settings for the Open Innovation Arena. In greater depth, this paper aims to analyse and reveal which factors influence the formation of an appropriate arena for doing open innovation and furthermore to prescribe how a firm can create an effective arena to gain access to external knowledge. This paper presents a review on open innovation literature with the purpose of examining the current understanding of factors influencing a firm's capacity to embrace and practice open innovation as well as understanding what is critical when fitting outside systems. It presents the results of a survey conducted among 25 researchers from INESC TEC, the Portuguese Institute for Systems and Computer Engineering, Technology, and Science. The study concludes that conditions, namely culture, leadership and strategy, are the main drivers to an open innovation arena, highlighting culture as the most important one. Highlights Nowadays, the goal of each organisation is to conquest competition and to win new customers. Firms must create physical locations where collaboration is encouraged. Companies must be able to diagnose, measure and question its innovation performance and potential. The Innovation Scoring System impacts a firm's capacity to embrace and practice open innovation; Impacting factors on Innovation Scoring System: Conditions, Resources, Processes and Results. Open Innovation is a powerful tool for the sustainable development of the companies.
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Pontedeiro, Elizabeth M., Paulo F. Heilbron, Jesus Perez-Guerrero, Jian Su, and Martinus Th van Genuchten. "Reassessment of the Goiânia radioactive waste repository in Brazil using HYDRUS-1D." Journal of Hydrology and Hydromechanics 66, no. 2 (June 1, 2018): 202–10. http://dx.doi.org/10.1515/johh-2017-0047.
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AbstractIn September 1987 an accident occurred with a cesium chloride (CsCl) teletherapy source taken from a cancer therapy institute in Goiânia, Brazil. Misuse of the abandoned source caused widespread contamination of radioactive material (about 50 TBq of137Cs) in the town of Goiânia. Decontamination of affected areas did lead to about 3,500 m3of solid radioactive wastes, which were disposed in two near-surface repositories built in concrete in 1995. This paper documents a safety assessment of one of the low-level radioactive waste deposits containing137Cs over a time period of 600 years. Using HYDRUS-1D, we first obtained estimates of water infiltrating through the soil cover on top of the repository into and through the waste and its concrete liners and the underlying vadose zone towards groundwater. Calculations accounted for local precipitation and evapotranspiration rates, including root water uptake by the grass cover, as well as for the effects of concrete degradation on the hydraulic properties of the concrete liners. We next simulated long-term water fluxes and137Cs transport from the repository towards groundwater. Simulations accounted for the effects of137Cs sorption and radioactive decay on radionuclide transport from the waste to groundwater, thus permitting an evaluation of potential consequences to the environment and long-term exposure to the public. Consistent with previous assessments, our calculations indicate that very little if any radioactive material will reach the water table during the lifespan of the repository, also when accounting for preferential flow through the waste.
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Keskküla, Kadri, Tambet Aru, Mihkel Kiviste, and Martti-Jaan Miljan. "Hygrothermal Analysis of Masonry Wall with Reed Boards as Interior Insulation System." Energies 13, no. 20 (October 9, 2020): 5252. http://dx.doi.org/10.3390/en13205252.
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When the masonry walls of buildings under heritage protection need to be restored and thermally improved, the only option is to use an interior insulation system. This is also the riskiest method of insulating walls in cold climates. Capillary active interior insulation systems have been proven to be the most reliable, minimizing the risk of mold growth and decay caused by condensation. They have also been proven to be less risky in wind-driven rain. The building studied is situated in a heritage-conservation area in downtown Tartu, Estonia, and therefore cannot be insulated from the exterior. This paper compares the hygrothermal performance of four different interior insulation systems with and without a heating cable and vapor barrier. In the first case, Isover Vario KM Duplex UV was placed between reed panels. In the second case, reed panels were used without the vapor barrier. Data loggers were applied between the reed panels and the original wall and inside the room to measure temperature and relative humidity in one-hour intervals. Exterior temperature and relative humidity values were taken from the Estonian University of Life Sciences Institute of Technology weather service station. In addition to the measurements taken in the case study building, calculations were made using heat-air-moisture (HAM) Delphin software to simulate the situation. The use of a smart vapor retarder (Isover Vario KM Duplex UV) with reed panels in the interior insulation system reduced the relative humidity level inside the wall. The vapor retarder improved the drying-potential compared to the interior insulation system without the vapor barrier.