Journal articles: 'Concentrating solution'

1

Lukashov, Vladimir, Sergey Romanko, Sergey Timofeev, and Alexander Protsenko. "RATE OF COMPONENTS EVAPORATION FROM SULFURIC ACID SOLUTION DURING ITS CONCENTRATING IN AIR FLOW." Chemistry & Chemical Technology 11, no. 3 (August 28, 2017): 344–48. http://dx.doi.org/10.23939/chcht11.03.344.

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Nakao, Shin-ich. "Optimization of Membrane Process for Concentrating Alcohol Solution." membrane 19, no. 5 (1994): 344–50. http://dx.doi.org/10.5360/membrane.19.344.

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Kartovskii, Yu V., V. B. Chernozubov, K. V. Glushko, V. A. Chemezov, D. S. Tretyakov, A. Yu Serkin, N. E. Chernykh, et al. "Industrial vacuum-evaporation unit for concentrating magnesium chloride solution." Chemical and Petroleum Engineering 47, no. 5-6 (September 2011): 301–4. http://dx.doi.org/10.1007/s10556-011-9463-5.

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Parra, S., S. Malato, J. Blanco, P. Péringer, and C. Pulgarin. "Concentrating versus non-concentrating reactors for solar photocatalytic degradation of p-nitrotoluene-o-sulfonic acid." Water Science and Technology 44, no. 5 (September 1, 2001): 219–27. http://dx.doi.org/10.2166/wst.2001.0290.

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The photocatalytic oxidation of the non-biodegradable p-nitrotoluene-o-sulfonic acid (p-NTS) in homogeneous (photo-Fenton reactions) and heterogeneous (with TiO2) solutions has been studied at a pilot-scale under solar irradiation at the Plataforma Solar de Almeria (PSA). In this study two different reactors were tested: a medium concentrating radiation system (Heliomans, HM) and a non-concentrating radiation system (CPC). Their advantages and disadvantages for p-NTS degradation have been compared and discussed. The degradation rates obtained in the CPC collector are around three times more efficient than in the HM collectors. However, in both systems, 100% of the initial concentration of p-NTS was removed. Kinetic experiments were performed in both systems using TiO2 suspensions. During the photodegradation, the disappearance of p-NTS was followed by HPLC, the mineralization of the solution by the TOC technique, the evolution of NO3-, NO2-, and SO4= concentration by ionic chromatography, the toxicity by the standard Microtox® test, and the biodegradability by BOD5 and COD measurements. The obtained results demonstrated the utility of the heterogeneous catalysis (using TiO2 as catalyst) as a pretreatment method that can be followed by a biological process.

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Kuzmin, I. I., T. Kh Chyong, Ya I. Simakina, A. V. Mikhailova, and Yu I. Fabelinsky. "Determination of Copper(II) Ions by Diffuse Reflectance Spectroscopy Method." Fine Chemical Technologies 14, no. 2 (May 20, 2019): 78–86. http://dx.doi.org/10.32362/2410-6593-2018-14-2-78-86.

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A method for copper(II) determination based on copper(II) ions interaction with the organic reagent picramine-ε, concentrating the formed complex on a solid-phase matrix and recording diffuse reflectance spectroscopy spectra by a portable combined LED miniphotometer was developed. Poly-ε-caproamide membranes were investigated as solid-phase matrixes. It was found that the diffuse reflectance coefficient of the studied membranes in the visible spectrum region does not depend on wavelength. So, the signal from membranes does not distort the results of the analysis. Factors controlling the process of sorption of the copper(II) complex with picramine-ε were studied. It was shown that the poly-ε-caproamide membranes are effective sorbents which provide the possibility of concentrating the analyte at a level higher than 105. The dependences of analytical signal on the acidity of the solution, the time of keeping the complex in the solution and the initial volume of the solution passed through the membrane were studied. Based on the obtained data, the optimal conditions of the analysis were found. Calibration dependence of the analytical signal on the concentration of copper(II) in model solutions was estimated. The method was tested for the determination of copper(II) ions in white wine. The method of additives was used for the analysis. It was found that the concentration of copper(II) ions in “Vagrus” wine is 0.0016 mkg/ml.

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Tewarson, R. P., H. Wang, J. L. Stephenson, and J. F. Jen. "Efficient solution of differential equations for kidney concentrating mechanism analyses." Applied Mathematics Letters 4, no. 6 (1991): 69–72. http://dx.doi.org/10.1016/0893-9659(91)90078-a.

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Zhang, Guiqing, Qixiu Zhang, and Kanggen Zhou. "Study on concentrating sulfuric acid solution by vacuum membrane distillation." Journal of Central South University of Technology 6, no. 2 (November 1999): 99–102. http://dx.doi.org/10.1007/s11771-999-0007-5.

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He, Jie, Lili Zhang, Kunming Zhang, Yingjie Qin, and Liqiang Liu. "Concentrating aqueous urea solution by using continuous-effect membrane distillation." Chemical Engineering Research and Design 104 (December 2015): 589–604. http://dx.doi.org/10.1016/j.cherd.2015.10.002.

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Oh, Hyeon-Ju, Taewon T. Han, and Gediminas Mainelis. "Performance of Two Different Techniques to Concentrate Samples for Bioaerosol Quantification." Atmosphere 11, no. 5 (May 14, 2020): 504. http://dx.doi.org/10.3390/atmos11050504.

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We evaluated two concentrating techniques that could be used to improve bioaerosol detection and quantification: A BioChromato Smart Evaporator C1 (BioChromato, Inc.) and two Concentrating Pipette (CP) models (CP-150 and CP-Select) (InnovaPrep, LLC). We determined the concentration factor (CF) (the concentration of particles in the final solution compared to the concentration in the initial solution) and the particle losses when processing the samples with polystyrene latex (PSL) beads and different species of bacteria. When processing total particles, regardless of the culturability status, the losses for the Evaporator were 3.70–23.89%; for the CP-models, the losses ranged from 0.20% to 67.22%. For the culturable particles processed with the CP devices, the losses ranged from 42.85% to 90.19% and were higher for Gram-negative pseudomonads compared to Gram-positive B. subtilis. Despite the loss of particles, both devices yielded more concentrated final solutions. The CF for the Evaporator was 3.59–10.92; the CF values for the CP devices ranged from 55.77 to 184.64 for total particles and from 6.29 to 96.52 for culturable bacteria. This higher CF was mainly achieved due to lower final suspension volumes. The study demonstrated that the two concentrators can improve particle detection, but that one should take particle losses into account.

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Loh, Chian Yong, Nur Zahidah Zahid, and Ooi Boon Seng. "Concentrating Fish Farm Effluent for its Nutrient Recovery via Nanofiltration." Journal of Applied Membrane Science & Technology 26, no. 1 (February 23, 2022): 77–93. http://dx.doi.org/10.11113/amst.v26n1.234.

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Excessive nutrients in aquaculture effluent have become an alarming environmental issue. However, current treatment methods for recovering nutrients are ineffective since the effluent contains trace amounts of nutrients. Pressure-driven nanofiltration (NF) is a potential solution to the problem of low concentration gradient. In this work, NF was applied to concentrate and recover the nutrients (ammonium (NH4+), phosphate, (PO43-), and nitrate ions (NO3-)) from the synthetic and real fish farm effluents. The experiments were first carried out to study the effect of membrane type, feed concentrations, and operating pressures on membrane performance. It is found that NF 90 membrane was able to retain more nutrient ions but compromise with a lower flux compared to NF 270. This study also revealed that an increase in feed concentration enhanced the concentrating ability for both PO43- and NO3- ions but reduced the concentrating factor of NH4+ ions. Moreover, both NF flux and concentrating factor increased with pressure. NF on actual fish farm effluents were investigated under optimal conditions (NF 90, 5 bar). Surprisingly, prefiltered effluent was found to have lower flux than raw effluent due to the presence of denser cake layer. NF could concentrate more nutrients from prefiltered fish farm effluent with concentrating factor up to 6.17 for PO43- ions and 1.55 for NH4+ions, claiming that NF was a promising approach for concentrating nutrients. These nutrients concentrate has an opportunity to be reapplied as fertilizer as a part of sustainable resource management.

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Ferrari, Federico, Maite Pijuan, Ignasi Rodriguez-Roda, and Gaetan Blandin. "Exploring Submerged Forward Osmosis for Water Recovery and Pre-Concentration of Wastewater before Anaerobic Digestion: A Pilot Scale Study." Membranes 9, no. 8 (August 5, 2019): 97. http://dx.doi.org/10.3390/membranes9080097.

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Applying forward osmosis directly on raw municipal wastewater is of high interest for the simultaneous production of a high quality permeate for water reuse and pre-concentrating wastewater for anaerobic digestion. This pilot scale study investigates, for the first time, the feasibility of concentrating real raw municipal wastewater using a submerged plate and frame forward osmosis module (0.34 m2) to reach 70% water recovery. Membrane performance, fouling behavior, and effective concentration of wastewater compounds were examined. Two different draw solutions (NaCl and MgCl2), operating either with constant draw concentration or in batch with draw dilution over time, were evaluated. Impact of gas sparging on fouling and external concentration polarization was also assessed. Water fluxes up to 15 L m−2 h−1 were obtained with clean water and 35 g NaCl/L as feed and draw solution, respectively. When using real wastewater, submerged forward osmosis proved to be resilient to clogging, demonstrating its suitability for application on municipal or other complex wastewater; operating with 11.7 g NaCl/L constant draw solution, water and reverse salt fluxes up to 5.1 ± 1.0 L m−2 h−1 and 4.8 ± 2.6 g m−2 h−1 were observed, respectively. Positively, total and soluble chemical oxygen demand concentration factors of 2.47 ± 0.15 and 1.86 ± 0.08, respectively, were achieved, making wastewater more suitable for anaerobic treatment.

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Lukashov, V. К., Y. V. Кostiuchenko, and V. I. Sereda. "Concentration of aqueous solutions of low-volatile liquids in a falling film with evaporation into a cross-gas flow." Voprosy Khimii i Khimicheskoi Tekhnologii, no. 3 (May 2021): 113–20. http://dx.doi.org/10.32434/0321-4095-2021-136-3-113-120.

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The article presents the results of the investigation of the process of concentrating solutions of low-volatile liquids in a flowing film under the conditions of evaporation in the cross-flow of neutral gas. The purpose of the study was to establish the features of solution composition change along the film length. The study was carried out using the developed mathematical model with experimental determination of model parameters: heat and mass transfer coefficients. It was found that at the beginning of the film, the change in the concentration of the solution has a character close to linear, and then the concentration sharply increases until the solvent evaporates completely. It was shown that this pattern of change in the composition of the solution is related to the distribution of the temperature of the solution along the length of the film. The intensity of the concentration process increases with decreasing initial flow rate of the solution and its initial concentration as well as with increasing initial temperature of the solution, initial temperature of the gas and temperature of the surface of the wall along which the film flows. The concentration intensity decreases with an increase in the velocity of the gas entering the space above the film. Comparison of the calculation results concerning aqueous glycerol solution with the experimental data showed their good agreement. The data obtained in the article allow calculating the height of the film concentrator nozzle at which a given concentration of the solution is provided.

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13

Kleinman, Mark, and Christine Whitehead. "Housing and regeneration: the problem or the solution." National Institute Economic Review 170 (October 1999): 78–86. http://dx.doi.org/10.1177/002795019917000111.

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Housing policy has traditionally been highly specific, concentrating on providing decent affordable homes. Now, however, housing is being seen more as a major factor in locating wider problems of deprivation and social exclusion, as well as an important part in solutions, not only by increasing housing quality, but more widely through its impact on the neighbourhood, regeneration and even urban renaissance. The article reviews a range of research findings on the role that housing plays in concentrating problems of deprivation and decay, on the relationship between deprivation and housing conditions, on how the housing market operates in relation to successful area-based employment and regeneration policies, and the implications that these results have on how area-based policies should be evaluated.

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Yurong, Liu, Cai Bangxiao, Chen Yiming, and Lang Kangmin. "Concentrating xylose solution by reverse osmosis with cellulose acetate dry membrane." Desalination 62 (January 1987): 193–201. http://dx.doi.org/10.1016/0011-9164(87)87019-4.

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15

Li, Jinli, Min Wang, Youjing Zhao, Hongjun Yang, and Yuan Zhong. "Enrichment of lithium from salt lake brine by forward osmosis." Royal Society Open Science 5, no. 10 (October 2018): 180965. http://dx.doi.org/10.1098/rsos.180965.

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Forward osmosis (FO) is a concentration process based on the natural phenomena of osmosis. It is considered a breakthrough technology that can be potentially used for concentrating solutions and suspensions. The diluted nature of brine restricts the treatment technologies that can be applied. Then, brine concentration by FO could represent a new emerging technology enabling the application of a wider range of treatment alternatives. The performance of concentrated brine depending upon FO membranes was studied at normal temperature and pressure in this research. Cellulose triacetates on radio-frequency-weldable non-woven support (CTA-NW) and a thin-film composite with embedded polyester screen support (TFC-ES) were compared; and their orientations were considered. The brine was from Chaerhan Salt Lake after extracting potassium as the feed solution, NaCl solution or MgCl 2 solution as the draw solution. The results indicated that CTA-NW exhibited better concentration performance than TFC-ES, while the water fluxes of the two membranes were exactly the opposite. In the case of CTA-NW in active layer facing feed solution orientation with MgCl 2 as the draw solution, the concentration factor of Li + was nearly 3.0. Quantitative structure–activity relationship of FO membranes and concentration characteristics was correlated, based on results of SEM, FTIR and contact angles studies. The concentration performance could be mainly attributed to the porosity and the thickness of FO membranes; while the water flux was dependent on the hydrophily of FO membrane surface.

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Cho, Yeonchul, Kihun Kim, Jaewoo Ahn, and Jaeheon Lee. "Application of Multistage Concentration (MSC) Electrodialysis to Concentrate Lithium from Lithium-Containing Waste Solution." Metals 10, no. 7 (June 28, 2020): 851. http://dx.doi.org/10.3390/met10070851.

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In order to manufacture lithium carbonate to be used as a raw material for a secondary lithium battery, lithium sulfate solution is used as a precursor, and the concentration of lithium is required to be 10 g/L or more. Electrodialysis (ED) was used as a method of concentrating lithium in a low-concentration lithium sulfate solution, and multistage concentration (MSC) electrodialysis was used to increase the concentration ratio (%). When MSC was performed using a raw material solution containing a large amount of sodium sulfate, the process lead time was increased by 60 min. And the concentration ratio (%) of lithium decreased as the number of concentration stages increased. In order to remove sodium sulfate, methanol was added to the raw material solution to precipitate sodium sulfate, and when it was added in a volume ratio of 0.4, lithium was not lost. Using a solution in which sodium sulfate was partially removed, fourth-stage concentration ED was performed to obtain a lithium sulfate solution with a lithium concentration of 10 g/L.

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Sahasrabudhe, Abhishek B., Ranjit R. Desai, and Siddharth K. Jabade. "Modeling and Simulation of a Freeze Concentration Technique for Sugarcane Juice Concentration." Applied Mechanics and Materials 110-116 (October 2011): 2768–73. http://dx.doi.org/10.4028/www.scientific.net/amm.110-116.2768.

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Freeze concentration is a process in which water is selectively separated out of binary solution in the form of ice, thereby concentrating solution. The freeze concentration system under consideration is a heat pump based freeze concentration system (FCS) that uses layer freezing process. The application of this system for the present paper is in the process of jaggery making used to concentrate sugarcane juice. A mathematical model is developed that helps in simulation of system under various operating parameters. The model is validated using previously published experimental results. Finally, based on simulation effects of various system parameters on ice growth and subsequent juice concentration have been discussed.

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Antipov, S. T., V. Yu Ovsyannikov, and A. A. Korchinskii. "Study of the cattle blood concentrating." Proceedings of the Voronezh State University of Engineering Technologies 80, no. 2 (October 2, 2018): 11–17. http://dx.doi.org/10.20914/2310-1202-2018-2-11-17.

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The urgency of more complete use of food blood of slaughter animals is due to the content of protein substances in it with a high digestibility of the organism, in terms of its content it can be equated to meat. However, the part of the processed and used blood for food purposes is only 3% by the meat processing industry. Using of the slaughter animals blood in concentrated form allows its use as one of the most important sources of animal origin protein and a number of other substances necessary for human being - fats, carbohydrates, enzymes, vitamins and mineral constituents. For partial canning and simultaneous increase in the content of useful components that make up the blood, it should be concentrated by the methods allowing maximum preservation of the entire complex of substances that make up its composition. A promising method is the concentration by moisture freezing. The concentration of cattle blood on a cyclic action plant was studied. Experimental data reflecting the change in the specific amount of freezed ice from the unit area of the heat exchange surface of the freezing plant and the loss of soluble substances contained in the blood removed from the frozen ice from the main operating parameters of the freezing plant were obtained. It was founf out that with a decrease in the average temperature of the plant evaporator wall, the specific amount of frozen ice from the blood of cattle increases monotonically nonlinearly. An increase in the initial content of dry soluble substances in the initial blood entering the concentration from 18.0 to 28.0% causes a nonlinear decrease in the specific amount of freeze-dried ice from the unit area of the heat exchange surface. It was noted that a decrease in the boiling point of the refrigerant in the evaporator of the freezing plant causes an increase in the dry matter content of the solution obtained by melting the frozen ice, and an increase in the blood flow of cattle washing the evaporator of the freezing plant, on the contrary, causes a decrease in the solids content in the solution obtained by the frozen ice melting.

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Stokke, Bjørn Torger, Arne Mikkelsen, and Arnljot Algsaeter. "An electrophoretic device concentrating charged macromolecules to a predetermined final solution volume." Analytical Biochemistry 148, no. 2 (August 1985): 527–32. http://dx.doi.org/10.1016/0003-2697(85)90263-5.

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20

Hara, Kiyotaka Y., Shuwa Yagi, Yoko Hirono-Hara, and Hiroshi Kikukawa. "A Method of Solubilizing and Concentrating Astaxanthin and Other Carotenoids." Marine Drugs 19, no. 8 (August 16, 2021): 462. http://dx.doi.org/10.3390/md19080462.

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The valuable marine carotenoid, astaxanthin, is used in supplements, medicines and cosmetics. In this study, crustacyanin, an astaxanthin-binding protein, was used to solubilize and concentrate astaxanthin. The recombinant crustacyanin of European lobster spontaneously formed an inclusion body when it was over-expressed in Escherichia coli. In this study, fusing the NusA-tag to the crustacyanin subunits made it possible to express in a soluble fraction and solubilize astaxanthin in aqueous solution. By cutting off the NusA-tag, the crustacyanin subunits generated the pure insoluble form, and captured and concentrated astaxanthin. Overall, the attaching and releasing NusA-tag method has the potential to supply solubilized carotenoids in aqueous solution and concentrated carotenoids, respectively.

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Malato, S., J. Blanco, C. Richter, D. Curcó, and J. Giménez. "Low-concentrating CPC collectors for photocatalytic water detoxification: comparison with a medium concentrating solar collector." Water Science and Technology 35, no. 4 (February 1, 1997): 157–64. http://dx.doi.org/10.2166/wst.1997.0109.

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The photocatalytic oxidation of 2,4-Dichlorophenol (DCP), using TiO2 suspensions under solar radiation, has been studied at pilot-plant scale at the Plataforma Solar de Almería (PSA). Two different reactor designs were tested: a medium concentrating radiation system called a Parabolic-Trough-Collector Reactor, PTCR, equipped with two motors (azimuth and elevation) to adjust the position of the module perpendicular to the sun, and a low-concentrating radiation system, the Compound-Parabolic-Concentrator Reactor, CPCR, facing south and inclined 37 degrees. Substrates were dissolved in water to required mg L−1 levels in a reservoir tank. In both cases, 0.2 g L−1 of the suspended TiO2 catalyst was used in a 250 L solution of the contaminant, which was recirculated through the photoreactors using a centrifugal pump and an intermediate reservoir tank. The advantages and disadvantages of the two types of photoreactors in DCP oxidation are compared and discussed. The strong potential of photocatalytic peroxydisulphate-assisted degradation in high DCP concentrations was demonstrated in both systems, and chemical actinometry (the decomposition reaction of oxalic acid by radiated uranyl salts) in the CPC reactor is compared with the results obtained in the PTC.

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Jin, Hua, Wenbin Liu, and Jianjun Zhang. "Singularly Perturbed Fractional Schrödinger Equation Involving a General Critical Nonlinearity." Advanced Nonlinear Studies 18, no. 3 (August 1, 2018): 487–99. http://dx.doi.org/10.1515/ans-2018-2015.

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AbstractIn this paper, we are concerned with the existence and concentration phenomena of solutions for the following singularly perturbed fractional Schrödinger problem:\varepsilon^{2s}(-\Delta)^{s}u+V(x)u=f(u)\quad\text{in }\mathbb{R}^{N},where{N>2s}and the nonlinearityfhas critical growth. By using the variational approach, we construct a localized bound-state solution concentrating around an isolated component of the positive minimum point ofVas{\varepsilon\rightarrow 0}. Our result improves the study made in [X. He and W. Zou, Existence and concentration result for the fractional Schrödinger equations with critical nonlinearities, Calc. Var. Partial Differential Equations 55 2016, 4, Article ID 91], in the sense that, in the present paper, theAmbrosetti–Rabinowitzcondition and themonotonicitycondition on{f(t)/t}are not required.

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Zhang, Ye Mei, and Zhi Juan Pan. "Conformational Transition of Regenerated Spider Silk in Water." Advanced Materials Research 796 (September 2013): 107–11. http://dx.doi.org/10.4028/www.scientific.net/amr.796.107.

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Spider silks have excellent mechanical properties, which can even compare with some high-performance synthetic materials. Although as reported, the impressive mechanical properties are closely related to the primary amino acid sequence, the conformation that molecular chains form is also an important determinant. In this paper, effects of solvent, pH value, temperature, centrifugation and concentrating on the secondary structure of regenerated Ornithoctonus huwenna spider dragline silk protein aqueous solution were investigated by circular dichroism. Spidroin solutions prepared from different LiBr solutions had a distinct combination of secondary structures. The increasing temperature and concentrating can promote the formation of β-sheet structure. While centrifugation was opposite, which elevate the content of β-turn structure. Circular dichroic spectra quantitatively verified an increased α-helix structure content but a decrease of random coil and β-turn structure content with the increasing of pH value.

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Levic, Ljubinko, Gordana Koprivica, Nevena Misljenovic, Bojana Filipcev, Olivera Simurina, and Tatjana Kuljanin. "Effect of starch as an edible coating material on the process of osmotic dehydration of carrot in saccharose solution and sugar beet molasses." Acta Periodica Technologica, no. 39 (2008): 29–36. http://dx.doi.org/10.2298/apt0839029l.

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The effect of edible coatings was studied with the objective to increase the content of solids during osmotic dehydration of foods. This study encompassed treatments of carrot with 3% maize starch solution applied in the form of single and double coatings. Samples of carrot were dehydrated in saccharose solution or sugar beet molasses as osmotic agents during 5h, at 55?C and normal pressure. It was concluded that double coating performed best, increasing the content of solids in the samples by more than four times. The possibility of recycling the osmotic solutions after concentrating them to the initial solid content was also considered.

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do Ó, João Marcos, and José Francisco de Oliveira. "Concentration-compactness and extremal problems for a weighted Trudinger–Moser inequality." Communications in Contemporary Mathematics 19, no. 01 (November 24, 2016): 1650003. http://dx.doi.org/10.1142/s0219199716500036.

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We discuss critical and subcritical general maximizing problems associated with a Trudinger–Moser type inequality for a class of weighted Sobolev spaces. The key of our approach relies on a concentration-compactness type result and sharp estimates for the concentration level of a Moser-type functional. In particular, we give an explicit concentrating sequence that is maximizing for the maximal concentration level. As an application, we prove the existence of a nontrivial solution for a family of quasilinear elliptic equations with critical growth.

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Zain, Omer S., and Surendra Kumar. "Simulation of a Multiple Effect Evaporator for Concentrating Caustic Soda Solution-Computational Aspects." JOURNAL OF CHEMICAL ENGINEERING OF JAPAN 29, no. 5 (1996): 889–93. http://dx.doi.org/10.1252/jcej.29.889.

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Champ, Simon, Wei Xue, Malcolm B. Huglin, Gregory D. Saunders, and Terrence G. Croucher. "Size Selective Concentrating of Poly(ethylene oxide) in Aqueous Solution by Thermosensitive Hydrogels." Macromolecular Rapid Communications 22, no. 10 (July 1, 2001): 768–72. http://dx.doi.org/10.1002/1521-3927(20010701)22:10<768::aid-marc768>3.0.co;2-1.

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Liu, Xi, and Wei Wang. "The Application of Nanofiltration Technology in Recovery of Ionic Liquids from Spinning Wastewater." Applied Mechanics and Materials 178-181 (May 2012): 499–502. http://dx.doi.org/10.4028/www.scientific.net/amm.178-181.499.

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In this paper, the effects of the concentration, temperature, and run-time of ionic liquids solution, on the rejection capacity of home-made hollow fiber composite nanofiltration membrane were studied. Then the nanofiltration membrane was used to the recover ionic liquids by concentrating spinning wastewater. The results shows that: The rejection rate of the composite nanofiltration membranes and its water fluxes lightly down with the concentration of ionic liquids increase; with running-time and temperature of ionic liquid solution increase, the rejection rate of the composite nanofiltration membranes decreases, but its water flux increases; the nanofiltration membrane can be use for recovering ionic liquid from the spinning wastewater and get very good recovery effects.

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Wang, Zhen, and Lei Huang. "A Hybrid Genetic Algorithm for Production Capacity Allocation Problem with Multiple Regional Demands in Supply Chain." Advanced Materials Research 945-949 (June 2014): 3107–11. http://dx.doi.org/10.4028/www.scientific.net/amr.945-949.3107.

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Concentrating on the supplier with limited production capacity in supply chain, this paper established a mathematical model for production capacity allocation problem with consideration of multiple regional demands. The genetic algorithm is employed as solution mainframe in which a heuristics rule is developed to initiate the population and an elite pool is adopted to store those solutions with outstanding fitness values. The experimental tests show that the proposed model and algorithm are feasible and effective.

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Liu, Weiming, and Miaomiao Niu. "Multi-peak positive solutions for the fractional Schrödinger–Poisson system." Communications in Contemporary Mathematics 20, no. 03 (February 21, 2018): 1750017. http://dx.doi.org/10.1142/s0219199717500171.

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In this paper, we study the existence of positive multi-peak solutions to the fractional Schrödinger–Poisson system [Formula: see text] where [Formula: see text] is a small parameter, [Formula: see text] is a positive function, [Formula: see text] and [Formula: see text] Under some given conditions which are given in Sec. ??, we prove the existence of a positive solution with m-peaks and concentrating near a given local maximum point of [Formula: see text]

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Cho, Yeonchul, Kihun Kim, Jaewoo Ahn, and Jaeheon Lee. "A Study on Lithium Hydroxide Recovery Using Bipolar Membrane Electrodialysis." Korean Journal of Metals and Materials 59, no. 4 (April 5, 2021): 223–32. http://dx.doi.org/10.3365/kjmm.2021.59.4.223.

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Bipolar electrodialysis was used in a process of desalting a lithium sulfate solution, converting it to lithium hydroxide and sulfuric acid, and concentrating and recovering them. The effects of the experimental variables such as applied voltage, the concentration of electrode solution, the concentration of raw material solution, volume ratio, and impurity were confirmed. The optimum conditions were investigated by comparing the conversion(%) of lithium hydroxide and sulfuric acid, the process time, and energy consumption. As the applied voltage was increased, the energy consumption tended to increase, but the processing time decreased significantly. As the concentration of lithium sulfate in the raw material solution increased, the conversion(%) of lithium hydroxide decreased. As the concentration of lithium sulfate increased, the energy consumption did not increase linearly, and energy consumption increased significantly. When a raw material solution of 0.5 M Li2SO4 or more is used in the bipolar electrodialysis process, an applied voltage of 25 V is preferable. As the applied voltage increased at a constant process time, the conversion(%) of LiOH and H2SO4 increased. Regarding the effect of the electrode solution concentration, when a 5.0 wt% electrode solution was used rather than a 3.0 wt% electrode solution, energy consumption decreased by more than 10%. When the volume of the raw material solution was increased, the processing time required for desalting increased. By using a low concentration raw material solution, it was confirmed that it was simultaneously possible to recover and concentrate lithium hydroxide and sulfuric acid through volume ratio control. When the raw material solution contained Na as an impurity, it was converted to NaOH with a surface LiOH, and it was not possible to separate the lithium and sodium.

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Palesko, Amy, and Chet Palesko. "Cost Comparison of Temporary Bond and Debond Methods For Thin Wafer Handling." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2014, DPC (January 1, 2014): 000459–78. http://dx.doi.org/10.4071/2014dpc-ta14.

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Miniaturization and increased performance demands are driving the industry to explore 2.5D and 3D packaging. Although progress has been made in recent years, many barriers remain. One primary cost driver for 2.5D and 3D processes is the temporary bond and debond method used for thin wafer handling. Various solutions are appearing on the market, but there is not a single method taking the lead as the obvious best choice. Many factors must be considered when looking at the total cost of a thin wafer handling solution. In this paper, we will use cost modeling to carry out detailed cost and yield trade-offs for temporary bond and debond methods. Instead of concentrating on one proposed solution that is available on the market, we will analyze a range of solutions, focusing on variables such as tool cost, material cost, throughput, and yield. With this analysis, we will determine the most significant cost drivers within the temporary bond and debond process and propose process details for a reasonable solution.

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Li, Guo Qiang, Yong Fa Zhang, Zhen Zhen Li, Yu Liang Shi, Ya Zhen Wang, and Lin Wang. "The Migration and Distribution Characteristics of the COD in the Enriching Process of HPF Coking Desulfurization Waste Solution." Advanced Materials Research 790 (September 2013): 37–40. http://dx.doi.org/10.4028/www.scientific.net/amr.790.37.

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The migration and distribution characteristics of the COD in the enriching process of Coking Desulfurization Waste Solution (CDWS) were researched in this paper. The results show that COD in the early and late condensate are all up to 10000mg/L and it is decreased at first and then increased in CDWS evaporating concentration process. This result is caused by substances containing organic at prophase and inorganic in the late. Therefore, removing the organic matter in the wastewater and controlling the temperature in CDWS concentrating process is the key to reduce the COD in condensate.

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34

Cho, Seung-Hyun. "Long term solution for K-POP globalization -Concentrating to the change in education system-." Journal of the Korea Academia-Industrial cooperation Society 16, no. 7 (July 31, 2015): 4418–23. http://dx.doi.org/10.5762/kais.2015.16.7.4418.

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35

Zhang, Guiqing, Qixiu Zhang, Kanggen Zhou, and Aiping Luo. "Study on concentrating sulfuric acid solution by membrane distillation with metal-PTFE composite membrane." Journal of Central South University of Technology 6, no. 2 (November 1999): 95–98. http://dx.doi.org/10.1007/s11771-999-0006-6.

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Zubrzycki, Igor Z. "Molecular Dynamics Study on an Adipokinetic Hormone Peptide in Aqueous Solution." Zeitschrift für Naturforschung C 55, no. 1-2 (February 1, 2000): 125–28. http://dx.doi.org/10.1515/znc-2000-1-223.

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Lom-AKH-I is a member of the adipokinetic hormone/ red pigment concentrating hormone (AKH / RPCH) family of peptides found in flying insects. A molecular dynamics simulation at room temperature (293 K) in water has been performed to survey the folding path of the Lom-AKH-I peptide in water and to establish the secondary structure of Lom-AKH-I. The obtained results indicate the presence of an undefined extended conformation.

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37

Palesko, Amy. "Cost Comparison of Temporary Bond and Debond Methods For Thin Wafer Handling." International Symposium on Microelectronics 2014, no. 1 (October 1, 2014): 000735–40. http://dx.doi.org/10.4071/isom-wp46.

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Miniaturization and increased performance demands are driving the industry to explore 2.5D and 3D packaging. Although progress has been made in recent years, many barriers remain. One primary cost driver for 2.5D and 3D processes is the temporary bond and debond method used for thin wafer handling. Various solutions are appearing on the market, but there is not a single method taking the lead as the obvious best choice. Many factors must be considered when looking at the total cost of a thin wafer handling solution. In this paper, we will use cost modeling to carry out detailed cost and yield trade-offs for temporary bond and debond methods. Instead of concentrating on one proposed solution that is available on the market, we will analyze a range of solutions, focusing on variables such as tool cost, material cost, throughput, yield, and interposer cost. With this analysis, we will determine the most significant cost drivers within the temporary bond and debond process and propose process details for a reasonable solution.

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38

Mironova, Elena, Yu Chen, Alan C. Pao, Karl P. Roos, Donald E. Kohan, Vladislav Bugaj, and James D. Stockand. "Activation of ENaC by AVP contributes to the urinary concentrating mechanism and dilution of plasma." American Journal of Physiology-Renal Physiology 308, no. 3 (February 1, 2015): F237—F243. http://dx.doi.org/10.1152/ajprenal.00246.2014.

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Arginine vasopressin (AVP) activates the epithelial Na+channel (ENaC). The physiological significance of this activation is unknown. The present study tested if activation of ENaC contributes to AVP-sensitive urinary concentration. Consumption of a 3% NaCl solution induced hypernatremia and plasma hypertonicity in mice. Plasma AVP concentration and urine osmolality increased in hypernatremic mice in an attempt to compensate for increases in plasma tonicity. ENaC activity was elevated in mice that consumed 3% NaCl solution compared with mice that consumed a diet enriched in Na+with ad libitum tap water; the latter diet does not cause hypernatremia. To determine whether the increase in ENaC activity in mice that consumed 3% NaCl solution served to compensate for hypernatremia, mice were treated with the ENaC inhibitor benzamil. Coadministration of benzamil with 3% NaCl solution decreased urinary osmolality and increased urine flow so that urinary Na+excretion increased with no effect on urinary Na+concentration. This decrease in urinary concentration further increased plasma Na+concentration, osmolality, and AVP concentration in these already hypernatremic mice. Benzamil similarly compromised urinary concentration in water-deprived mice and in mice treated with desmopressin. These results demonstrate that stimulation of ENaC by AVP plays a critical role in water homeostasis by facilitating urinary concentration, which can compensate for hypernatremia or exacerbate hyponatremia. The present findings are consistent with ENaC in addition to serving as a final effector of the renin-angiotensin-aldosterone system and blood pressure homeostasis, also playing a key role in water homeostasis by regulating urine concentration and dilution of plasma.

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Gillilan, Richard, Søren Skou, Thomas Jensen, Bente Vestergaard, and Magda Skou. "Microfluidic dialysis on the beamline: experiment and theory." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C412. http://dx.doi.org/10.1107/s2053273314095874.

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Biological small angle x-ray solution scattering requires sufficient sample concentration to yield good signal while at the same time avoiding interparticle interference or the formation of unwanted oligomers or aggregates. The mere act of concentrating some samples risks rendering them unfit for SAXS measurements and the limit to which a sample may be concentrated before problems occur is often unknown a priori; aggregation is not generally regarded as a reversible process. At the same time, sample behavior at high concentrations is increasingly important not just for characterization of equilibria, or e.g. applications in the pharmaceutical industry, but also for understanding potential molecular crowding effects. We have constructed a microfluidic dialysis setup that permits on-demand concentration of protein samples at the beamline. Rather than generating dilution series to explore concentration effects, this approach produces true "concentration series", efficiently working from dilute sample upward. We experimentally demonstrate that useful concentrations can be achieved on practical timescales and that buffer exchange can be performed. Convection-diffusion modeling shows that the dialysis chip may actually retard aggregates, thus resulting in some degree of incidental sample purification. Based on model projections, the theoretical limits and potential of chip-dialysis will be described.

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Zawieja, D. C., and B. J. Barber. "Lymph protein concentration in initial and collecting lymphatics of the rat." American Journal of Physiology-Gastrointestinal and Liver Physiology 252, no. 5 (May 1, 1987): G602—G606. http://dx.doi.org/10.1152/ajpgi.1987.252.5.g602.

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Lymph samples were obtained from villus initial and mesenteric prenodal collecting lymphatics of the anesthetized rat using standard micropuncture techniques. The protein concentrations of the lymph samples were determined using a fluorometric microassay. These procedures were performed on preparations either superfused with a modified Krebs solution or covered with paraffin oil. The protein-concentrating ability of the intestinal lymphatics was evaluated to test the osmotic theory of lymph formation. The mean initial lymph protein concentration in superfused preparations was 2.08 g/dl (SE = 0.20). The lymph protein concentration in collecting vessels in superfused preparations was 2.20 g/dl (SE = 0.19). The protein concentration from initial lymphatics in oil-covered preparation was 2.48 g/dl (SE = 0.17). The lymph protein concentration in collecting vessels in oil-covered preparations was 2.32 g/dl (SE = 0.15). The difference between initial and collecting lymph protein concentration found was an order of magnitude lower than that predicted by the osmotic theory. These results cast serious doubts on the effectiveness of the osmotic mechanism of lymph formation as it is presently defined.

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TAKAHASHI, Y., H. YAMAZAKI, K. ISHII, S. MATSUYAMA, T. SATO, H. ORIHARA, and G. C. JON. "PIXE Analysis for Drainage from a Radioisotope Laboratory." International Journal of PIXE 08, no. 01 (January 1998): 57–67. http://dx.doi.org/10.1142/s0129083598000078.

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PIXE technique has been applied to quantitative analysis of thorium and uranium ions in drainage from a radioisotope laboratory of Tohoku University. Two kinds of targets were prepared and analyzed with an in-air vertical PIXE system of 3 MeV protons. The concentrations of thorium and uranium higher than 40 ppb were easily determined by 3-μC irradiation on targets which are made from a 0.12-ml solution containing Ga-internal standard evaporated on a hand-made polycarbonate film. Uranium(VI) ions in a 25-ml sample were preconcentrated into a thin uniform target containing Zr or Pd as an internal standard by means of dibenzyldithiocarbamate complexation with subsequent condensation into dibenzylidene-D-sorbitol gels, and low concentration of 10 ppb was precisely determined by PIXE measurement. This method does not work for concentrating thorium ions. The PIXE analysis for these two kinds of targets has good sensitivity and precision enough to determine concentrations of thorium and uranium lower than their permissible concentration limits in drainage from a radioisotope laboratory.

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Palamarchuk, M. S., E. A. Tokar, M. V. Tutov, and A. M. Yegorin. "Deactivation of Spent Ion-exchange Resins Contaminated by Cesium and Cobalt Radionuclides." Ecology and Industry of Russia 23, no. 4 (April 3, 2019): 20–24. http://dx.doi.org/10.18412/1816-0395-2019-4-20-24.

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Simulation of iron oxide (magnetite and maghemite) and aluminosilicate (sillimanite and cyanite) deposits formed on the surface of spent ionexchange resins in the process of decontamination of liquid radioactive waste contaminated by cesium and cobalt radionuclides has been performed. A method of deep deactivation of spent ion-exchange resins contaminated by aluminosilicate and iron oxide deposits using alkaline and acidic solutions containing Zn-EDTA complexes has been suggested. The method of two-stage concentrating of cesium radionuclides using selective sorption materials (resorcinol-formaldehyde resin and Thermoxid-35 ferrocyanide sorbent) has been improved. The method advantage consists in using a solution containing EDTA complexes for elution of cesium radionuclides from the resorcinol-formaldehyde resin with their transition onto Thermoxid-35. High stability of the resorcinol-formaldehyde resin and Thermoxid-35 in the course of concentrating has been demonstrated. A scheme of deactivation of spent ion-exchange resins, which enables one to decrease the volume of secondary wastes due to utilization of a circulating water supply, has been suggested.

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Rathna, Ravichandran, and Ekambaram Nakkeeran. "Performance of High Molecular Weight Osmotic Solution for Opuntia Betacyanin Concentration by Forward Osmosis." Current Biotechnology 8, no. 2 (January 20, 2020): 116–26. http://dx.doi.org/10.2174/2211550108666191025112221.

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Background: Forward osmosis is a sustainable membrane process employed for concentrating thermo-sensitive compounds to minimize storage and transportation costs with improved shelf life. Objective: In this study, the intervention of high molecular weight osmotic agents in the concentration of Opuntia betacyanin using forward osmosis was studied. Furthermore, the statistical model was used to estimate the probabilistic behavior of the forward osmosis process during concentration. Method: By using 2k-full factor analysis, the hydrodynamic variables, such as flow rate (50 and 150 mL/min) and temperature (20 and 50ºC) of the feed solution and osmotic agent solution (OAS) were selected. The study focused on inquiring and developing a statistically significant mathematical model using four independent variables on transmembrane flux, concentration factor and concentrate recovery. Results: Betacyanin feed flow rate of 50 mL/min at 28ºC, and OAS flow rate of 150 mL/min at 50ºC were determined as optimal conditions with a 2.5-fold increase in total soluble solids for a processing time of 4 h. Furthermore, forward osmosis enhanced the betacyanin concentration from 898 to 1004 mg/L and 98.7% recovery with 0.40 L/m2h transmembrane flux with comparable improvement in its physicochemical characteristics. The lower p-value of the main effects on the responses validated the significance of the process parameters on betacyanin concentration. Conclusion: The study suggested that a high molecular weight sucrose could be used as an osmotic agent for the concentration of Opuntia betacyanin during forward osmosis.

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Kaysheva, Anna L., Pavel A. Frantsuzov, Arthur T. Kopylov, Tatyana O. Pleshakova, Alexander A. Stepanov, Kristina A. Malsagova, Alexander I. Archakov, and Yurii D. Ivanov. "Mass Spectrometric Identification of Proteins Enhanced by the Atomic Force Microscopy Immobilization Surface." International Journal of Molecular Sciences 22, no. 1 (January 4, 2021): 431. http://dx.doi.org/10.3390/ijms22010431.

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An approach to highly-sensitive mass spectrometry detection of proteins after surface-enhanced concentrating has been elaborated. The approach is based on a combination of mass spectrometry and atomic force microscopy to detect target proteins. (1) Background: For this purpose, a technique for preliminary preparation of molecular relief surfaces formed as a result of a chemical or biospecific concentration of proteins from solution was developed and tested on several types of chip surfaces. (2) Methods: mass spectrometric identification of proteins using trailing detectors: ion trap, time of flight, orbital trap, and triple quadrupole. We used the electrospray type of ionization and matrix-assisted laser desorption/ionization. (3) Results: It is shown that when using locally functionalized atomically smooth surfaces, the sensitivity of the mass spectrometric method increases by two orders of magnitude as compared with measurements in solution. Conclusions: It has been demonstrated that the effective concentration of target proteins on specially prepared surfaces increases the concentration sensitivity of mass spectrometric detectors—time-of-flight, ion trap, triple quadrupole, and orbital ion trap in the concentration range from up to 10−15 M.

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45

Dong, Heng, Jian You Wang, Hui Xia Lu, and Hong Bing Yu. "Nickel-Containing Effluent Reclaming by Bipolar Membrane-Electrodeionization Process." Advanced Materials Research 233-235 (May 2011): 942–48. http://dx.doi.org/10.4028/www.scientific.net/amr.233-235.942.

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Electrodeionization(EDI) is an electro-membrane process with high efficiency for deep desalinating, where water dissociation mechanism occurring on the surface of ion exchange membranes and resins typically exsits and acts. But when used to treat heavy metal-containing solutions such as effluents from the electronic industry, the EDI will suffer from metal-hydroxides precipitation which would destroy the separation process irreversible. With the primary aim to solve that problem, an electrodeionization process coupled with bipolar membrane (BMEDI) was developed together with a preacidification method. The effects of separating and concentrating heavy metal ions by the BMEDI were studied with NiSO4 solution containing 24 mg×L-1 Ni2+ ions. The results suggested that, the nickel-concentration in the dilute products were both below the analysis limit at constant current densities of 40 mA·cm-2 and 10 mA·cm-2, while a concentration factor of 31 was achieved at 40 mA·cm-2. In addition, no Ni(OH)2 precipitation was found in all the compartments throughout the experiments, which provide a guarantee of good stability for long-time operation.

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46

Lv, Ning-Ning, Chuan-Ming Du, Hui Kong, and Yao-Hui Yu. "Leaching of Phosphorus from Quenched Steelmaking Slags with Different Composition." Metals 11, no. 7 (June 25, 2021): 1026. http://dx.doi.org/10.3390/met11071026.

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Separating P2O5 from steelmaking slag is the key to achieving optimum resource utilization of slag. If the P-concentrating 2CaO∙SiO2–3CaO∙P2O5 solid solution was effectively separated, it can be a potential phosphate resource and the remaining slag rich in Fe2O3 and CaO can be reutilized as a flux in steelmaking process. In this study, a low-cost method of selective leaching was adopted, and hydrochloric acid was selected as leaching agent. The dissolution behavior of quenched steelmaking slags with different composition in the acidic solution was investigated and the dissolution mechanism was clarified. It was found that the P dissolution ratio from each slag was higher than those of other elements, achieving an effective separation of P and Fe. The dissolution ratios of P, Ca, and Si decreased as the P2O5 content in slag increased. A higher Fe2O3 content in slag led to a lower P dissolution ratio. Increasing slag basicity facilitated the dissolution of P from slag. The residue mainly composed of matrix phase and the P2O5 content decreased significantly through selective leaching. The P dissolution ratio from slag was primarily determined by the P distribution ratio in the 2CaO∙SiO2–3CaO∙P2O5 solid solution and the precipitation of ferric phosphate in the leachate. The P-concentrating solid solution was effectively separated from quenched steelmaking slag, even though hydrochloric acid was used as leaching agent.

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Kirilchuk, Maksim, and Adam Mustapha. "Comparative experiments on the activation cyanide and chloride re-leaching of gold from the secondary mineral material of heaps of Aprelkovo mine." E3S Web of Conferences 192 (2020): 02016. http://dx.doi.org/10.1051/e3sconf/202019202016.

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This article presents the results of comparative experiments on the activation chloride and activation carbonate-cyanide leaching of gold from the secondary mineral material of heaps of Aprelkovo mine. A cyanide scheme with a gradual increase in the cyanide concentration in the pregnant solution was adopted as a control scheme for percolation leaching. To establish the maximum recovery of gold and associated components, preliminary experiments with agitational cyanide leaching were carried out. In the course of the experimental work, some of the problems of gold recovery according to the classical cyanide scheme applicable to this deposit were identified and, thanks to the use of activated solutions, were solved. The reasons for the insufficiently high recovery are clogging and limited access of the complexing agent to encapsulated and chemically bound gold inclusions due to their high dispersion in the crystal lattices of concentrating minerals and the presence in the ore of minerals that tend to absorb water with a pronounced hydration effect.

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Cassani, Daniele, Youjun Wang, and Jianjun Zhang. "A Unified Approach to Singularly Perturbed Quasilinear Schrödinger Equations." Milan Journal of Mathematics 88, no. 2 (November 16, 2020): 507–34. http://dx.doi.org/10.1007/s00032-020-00323-6.

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AbstractIn this paper we present a unified approach to investigate existence and concentration of positive solutions for the following class of quasilinear Schrödinger equations, $$-\varepsilon^2\Delta u+V(x)u\mp\varepsilon^{2+\gamma}u\Delta u^2=h(u),\ \ x\in \mathbb{R}^N, $$ - ε 2 Δ u + V ( x ) u ∓ ε 2 + γ u Δ u 2 = h ( u ) , x ∈ R N , where $$N\geqslant3, \varepsilon > 0, V(x)$$ N ⩾ 3 , ε > 0 , V ( x ) is a positive external potential,h is a real function with subcritical or critical growth. The problem is quite sensitive to the sign changing of the quasilinear term as well as to the presence of the parameter $$\gamma>0$$ γ > 0 . Nevertheless, by means of perturbation type techniques, we establish the existence of a positive solution $$u_{\varepsilon,\gamma}$$ u ε , γ concentrating, as $$\varepsilon\rightarrow 0$$ ε → 0 , around minima points of the potential.

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Raven, John A., Andrew M. Johnston, Richard Parsons, and Janet Kübler. "The occurrence, and influence on photolithotrophs, of high oxygen concentrations." Proceedings of the Royal Society of Edinburgh. Section B. Biological Sciences 102 (1994): 193–201. http://dx.doi.org/10.1017/s0269727000014111.

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SynopsisHyperoxia (O2in solution in excess of air-equilibrium values) occurs in certain photosynthesising cells which use inorganic C concentrating mechanisms, and as a result of abiological mechanisms. Geochemical evidence suggests that the atmosphere may have had significantly higher O2partial pressures in the past (e.g. the Upper Carboniferous) than occurs today. Biochemical effects of high O2concentrations in solution include inhibition of RUBISCO (competitive with CO2) and nitrogenase, as well as damage caused by higher levels of toxic O species (H2O2, O2and, especially,1O2and OH). The influence of high (twice the extant level) atmospheric O2on growth of non-N2-fixers is as predicted from the properties of RUBISCO and the occurrence of inorganic C concentrating mechanisms. Acclimation of N2-fixers to twice the extant O2level involves increased restriction on O2diffusion to nitrogenase so that growth is not inhibited (unless the high O2has access to the C3photosynthesis apparatus). Evidence as to the effect of hyperoxia on quenchers and scavengers of toxic O species is equivocal. Cells exposed to high O2probably have higher mutation rates as a result of higher levels of toxic O species, although the production and maintenance of ‘stem’ cells may occur in parts of the plants with relatively low O2levels.

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Zhang, Gui Fang, Peng Yan, and Qing Rong Yang. "Experimental Study on Concentrating Scandium by Leaching from Associated Scandium Ore." Advanced Materials Research 734-737 (August 2013): 1033–36. http://dx.doi.org/10.4028/www.scientific.net/amr.734-737.1033.

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Based on the benefication of the complex silicate ore containing scandium, the research about aid-leaching agent used in the leaching of the scandium concentrate was been conducted. And the suitable leaching agent and aid-leaching agent which the useful ions entered into leaching liquid and the harmful ions were kept in leaching residue were been found according to the experiment results. For the scandium of sample existed various complex silicate ore as isomorphism form, the research has adopted hydrochloric acid with aid-leaching agent to dissociate the silicate ore and make scandium entering into solution. The research results has shown that the scandium leaching rate could reach 92.06% under the optimal conditions which the hydrochloric acid concentration is 22.8%, the dosage of aid leaching agent is 6%, liquid solid ratio is 4:1, particle size of leaching material totally is less than 0.15mm and leaching time is 8h.

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Journal articles on the topic 'Concentrating solution'

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