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Journal articles on the topic 'AQUEOUS PRECIPITATION METHOD'

Author: Grafiati

Published: 11 September 2023

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1

Zhu, Qing Xia, Wei Hui Jiang, Hong Da Wang, and Chuan Shao. "Preparing Fluorhydroxyapatite by Aqueous Precipitation Method." Advanced Materials Research 412 (November 2011): 167–70. http://dx.doi.org/10.4028/www.scientific.net/amr.412.167.

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The nanosized fluorhydroxyapatite (FHA) had been synthesized by aqueous precipitation method. The effects of synthesis temperature,fluoride ion concentration and pH value on the fluoride substitution were investigated.The phase composition and the change of crystal structure were characterized by X-ray diffraction and fourier transform infrared spectroscopy. The results show that crystal lattice parameters and bond energy make changes by incorporation of F in the structure.The size of FHA crystals increase as the precipitation temperature. The phase composition of FHA is mainly controlled by the pH value.

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2

Shi, He Bin, Hong Zhong, Yu Liu, Jin Yan Gu, and Chang Sheng Yang. "Effect of Precipitation Method on Stoichiometry and Morphology of Hydroxyapatite Nanoparticles." Key Engineering Materials 330-332 (February 2007): 271–74. http://dx.doi.org/10.4028/www.scientific.net/kem.330-332.271.

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This paper reports synthesis of hydroxyapatite nanoparticles by three precipitation methods. Homogeneous aqueous solution of Ca(NO3)2 and H3PO4 was used as precursor solution, and NH3•H2O was precipitator. Calcium deficient hydroxyapatite nanorods were obtained by adding the precipitator into precursor solution, near stoichiometric hydroxyapatite nanoparticles were derived from adding precursor solution into the precipitator, and smaller hydroxyapatite nanoparticles were prepared by adding precipitator and precursor solution simultaneously into a reaction vessel. The stoichiometry of hydroxyapatite was mainly affected by pH at precipitation reaction process. The crystal size and shape of hydroxyapatite particles was related to Ostwald ripening. The stoichiometry and morphology of hydroxyapatite nanoparticles can be controllable by selecting suitable coprecipitation process.

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3

Varshosaz, Jaleh, Saeedeh Ahmadipour, Majid Tabbakhian, and Shokoufeh Ahmadipour. "Nanocrystalization of Pioglitazone by Precipitation Method." Drug Research 68, no. 10 (April 9, 2018): 576–83. http://dx.doi.org/10.1055/a-0591-2506.

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Abstract Background Poor solubility in aqueous medium limits the use of many drugs. Different methods have been adopted to promote the rate of dissolution of slightly water soluble drugs. Crystallization improves solubility, and bioavailability by increasing the surface area of slightly water soluble drugs. Pioglitazone (PGZ), which is a class II Biopharmaceutical Classification System drug has a slight solubility in water and a slow rate of dissolution, which may have a negative effect on its metabolism leading to a therapeutic failure. Aim The aim of this study was to improve the solubility of PGZ-HCl; an antidiabetic drug using precipitation method. Materials and Methods Formulations were prepared with polyethylene glycol 6000 and isomalt using different speed of homogenizer and quantity of solvent by precipitation method. Drug-polymer interactions were examined using differential scanning calorimetry (DSC), and Powder X-Ray Diffraction (PXRD). Surface structure were shown by SEM photographs. Results The particle size was significantly decreased and solubility was enhanced with increase speed, ethanol solvent and increase stabilizer, however very high amount of stabilizer resulted in a decrease in solubility. Conclusion This result however showed that solid dispersion technique is a potential method for increasing dissolution profile of a poorly aqueous soluble agent.

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Sun, Yi, Xiao Yi Shen, and Yu Chun Zhai. "Preparation of Ultrafine ZnO Powder by Precipitation Method." Advanced Materials Research 284-286 (July 2011): 880–83. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.880.

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Ultrafine ZnO powder was synthesized by precipitation method, using zinc sulfate and aqueous ammonium carbonate as raw material and precipitant, respectively. The influence of the concentration of aqueous ammonium carbonate on the precipitation rate of Zn2+ was discussed and their relationship was also illustrated. The precipitation rate of Zn2+ increased gradually with the mol ratio of CO32-to Zn2+, which reached up to more than 96% when the mol ratio was 1.2. In addition, the crystal structure and morphology of the precursor and ZnO powder were also characterized using XRD and SEM. The results indicated that ZnO powder was hexagon wurtzite structure and spherical figure with high purity and regular crystal form.

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Harden, F. J., Iain R. Gibson, and J. M. S. Skakle. "Simplification of the Synthesis Method for Silicon-Substituted Hydroxyapatite: A Raman Spectroscopy Study." Key Engineering Materials 529-530 (November 2012): 94–99. http://dx.doi.org/10.4028/www.scientific.net/kem.529-530.94.

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The addition of silicon ions to hydroxyapatite (HA) provides a more inorganic bone-like chemical composition compared to stoichiometric HA. It is known to aid the bioactivity of the material and to improve the rates of osseointegration, osteoconduction and bone mineralisation. The literature, however, lacks detailed information regarding each step of the aqueous precipitation procedure to produce silicon-substituted HA (Si-HA). The current work utilised Raman spectroscopy at each stage of the aqueous precipitation method to determine how the silicate is incorporated into the HA structure when producing Si-HA. Raman spectra indicated that at the initial stages of the reaction the disilicate ion (Si2O76-) formed with the orthosilicate (SiO44-) ion becoming more dominant after sintering. The results demonstrated that the form of silicate in the Si-HA aqueous precipitation method can be tracked using Raman spectroscopy.

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6

Suwanboon, Sumetha, and Pongsaton Amornpitoksuk. "Structural, Optical and Photocatalytic Properties of ZnO Nanoparticles Prepared by Precipitation Method." Advanced Materials Research 979 (June 2014): 163–66. http://dx.doi.org/10.4028/www.scientific.net/amr.979.163.

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ZnO nanoparticles were synthesized from PEG600 diacid modified-Zn (CH3COO)2.2H2O solution by precipitation method and an aqueous NaOH solution was used as precipitating agent. The crystal structure, morphology and optical property of ZnO nanoparticles were characterized by XRD, SEM and UV-Vis spectrophotometer, respectively. The crystallinity increased while the Eg value decreased as a function of PEG600 diacid concentrations. The ZnO nanoparticles that had the highest crystallinity and lowest Eg value exhibited the highest efficiency of photocatalytic degradation of about 90% when irradiating with a UV light for 3 h.

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Wang, Li Qin, Xiang Ni Yang, Yang Han, Rui Jun Zhang, and Yu Lin Yang. "Synthesis and Characterization of ZnO Nanoparticles in the Method of Precipitation." Key Engineering Materials 474-476 (April 2011): 1725–29. http://dx.doi.org/10.4028/www.scientific.net/kem.474-476.1725.

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ZnO nanoparticles were synthesized in the method of precipitation, and they were characterized by the means of the transmission electron microscopy (TEM), the X-ray powder diffraction (XRD), the thermogravimetric analysis and differential thermal analysis (TG-DTA), and the Fourier transform infrared spectroscopy (FT-IR). Also their photocatalytic and degradation performance for the methyl orange aqueous solution were studied. The research results showed as-prepared ZnO nanoparticles were spherical crystals in hexagonal crystal system, and their size distribution was mainly in the range of 20-30 nm. The annealing temperature was about 390 °C, and a few organics remained, which may be helpful for the formation of ZnO particles. They had integrated crystal form, high crystallinity and thermal stability. Moreover, the obtained ZnO nanoparticles had excellent photocatalytic and degradation performance for the methyl orange aqueous solution. When reacted for 3.5 h, the degradation rate of the methyl orange aqueous solution was up to about 97%.

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8

Hsueh, Hui Chung, Zue Chin Chang, Chang Ching You, and C. B. Lin. "A Novel Method to Fabricate Silver Chloride Films." Applied Mechanics and Materials 117-119 (October 2011): 652–55. http://dx.doi.org/10.4028/www.scientific.net/amm.117-119.652.

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Abstract: This investigation develops a novel method for fabricating silver chloride films by the heterogeneous precipitation of sodium chloride from aqueous solution and supersaturated solid-state silver nitrate out of aqueous solution. The morphology of the bottom surface of the silver chloride film thus obtained comprises numerous porous stick structures. The top surface comprises equiaxed grains, and columnar grains are observed in the cross-section.

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9

Chang, Yajing, Xiaopeng Cheng, Jinhua Zhang, and Dabin Yu. "Highly stable CdTe quantum dots hosted in gypsum via a flocculation–precipitation method." Journal of Materials Chemistry C 7, no. 39 (2019): 12336–42. http://dx.doi.org/10.1039/c9tc04412d.

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10

Ding, Jie Feng, Jian Fen Li, Wei Yi Dan, Qiang Sheng Wang, and Han Fen Zhou. "Process Optimization and Preparation of Ferric Oxide Nanoparticles by Homogeneous Precipitation Method." Applied Mechanics and Materials 401-403 (September 2013): 683–87. http://dx.doi.org/10.4028/www.scientific.net/amm.401-403.683.

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For the purpose of developing an effective Fe2O3-doped nickel-based catalysts to be used in biomass gasification, Fe2O3nanoparticles were prepared by homogeneous precipitation method involving an aqueous solution of Fe (NO3)3·9H2O and urea as precipitator. Different approaches, such as XRD and SEM, were used to characterize the products. Meanwhile, the effects of various technical parameters in preparation process on the yield of products were investigated, and optimal conditions for preparing Fe2O3nanoparticles were found as follows: the molar ratio of urea to Fe (NO3)3·9H2O for 5:1, temperature of precipitation reaction for 125°C, concentration of iron salt for 0.20mol/L. The Fe2O3nanoparticles prepared under the optimal conditions were spherical in shape and well dispersed; they had high purity and a fine crystal phase of cubic syngony with a mean particle size of about 28nm.

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11

Takarini, Veni, Lia A. T. W. Asri, Nina Djustiana, and Bambang Kismono Hadi. "Simple precipitation method to reduce the particle size of glutinous rice flour: physicochemical evaluation." Materials Research Express 9, no. 2 (February 1, 2022): 025301. http://dx.doi.org/10.1088/2053-1591/ac4ebd.

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Abstract Submicron- and nano-sized starch can be employed as organic filler particles in composites. Starch with this size range can be used as an alternative filler for dental impression materials that are used to create an accurate replica or mold of the hard and soft oral tissues. In this work we selected glutinous rice flour as a starch source comprising a high amylopectin content. We carried out two different precipitation methods to reduce the particle size of glutinous rice flour and evaluated the changes on the particle size, morphological, crystallinity, and thermal properties. First precipitation method involved addition of ethanol into an aqueous phase consisting of flour and water, while in the second method (instant precipitation) we added the aqueous phase into the ethanol organic phase. We observed that both methods lead to the decrease of the glutinous rice flour crystallinity from 21.85% to around 4.30%–10.99%. The precipitation also decreased the gelatinization temperature of the treated filler particles from 87.7℃ to around 80.3–85.3℃. We found the morphological transition of glutinous rice flour from polyhedral to nearly spherical-shaped particles. First method resulted in agglomerated particles that were not perfectly distributed. While by employing the instant precipitation method we successfully reduced the particle size from 3411.5 nm to 259.5 nm. To conclude, instant precipitation method offers a simple route to reduce the particle size of glutinous rice flour to submicron-sized range.

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12

ZHU, Qing-Xia, Wei-Hui JIANG, Hong-Da WANG, and Chuan SHAO. "Investigation on Preparation Factors for Fluorhydroxyapatite by an Aqueous Precipitation Method." Journal of Inorganic Materials 26, no. 12 (November 29, 2011): 1335–40. http://dx.doi.org/10.3724/sp.j.1077.2011.11399.

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13

Gao, Bing, Chao Shen, Shuanglong Yuan, Yunxia Yang, and Guorong Chen. "Synthesis of Highly Emissive CdSe Quantum Dots by Aqueous Precipitation Method." Journal of Nanomaterials 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/138526.

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CdSe quantum dots (QDs) with high quantum yield (QY) up to 76.57% are synthesized using the aqueous precipitation method. With the control ofSeSO32-concentration in Se precursor, the nucleation speed and concentration of CdSe QDs are increased. The mass of obtained Cd2+and Se2+in nanocrystal is measured by inductively coupled plasma atomic emission spectrometry (ICP-AES). XRD and HRTEM are used to identify the crystal phase and morphology of the products which are pure CdSe crystals in the cubic zinc blende phase and uniformly dispersed in the solution with the size between 2 nm and 2.3 nm. Results demonstrate that the emission wavelength of CdSe QDs is 500 nm~560 nm along with the increased temperature 50°C~90°C and prolonged time 5 min~25 min.

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14

Sepulveda-Guzman, S., B. Reeja-Jayan, E. de la Rosa, A. Torres-Castro, V. Gonzalez-Gonzalez, and M. Jose-Yacaman. "Synthesis of assembled ZnO structures by precipitation method in aqueous media." Materials Chemistry and Physics 115, no. 1 (May 2009): 172–78. http://dx.doi.org/10.1016/j.matchemphys.2008.11.030.

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15

An, Li Juan, Jun Wang, Tie Feng Zhang, Han Lin Yang, and Zhi Hui Sun. "Synthesis of ZnO Nanoparticles by Direct Precipitation Method." Advanced Materials Research 380 (November 2011): 335–38. http://dx.doi.org/10.4028/www.scientific.net/amr.380.335.

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In this study, Zinc oxide (ZnO) nanoparticles were prepared using Zinc nitrate (Zn(NO3)2) and Ammonium carbonate ((NH4)2CO3) in aqueous solutions with proper concentration by a direct precipitation method. The properties of ZnO nanoparticles synthesized were characterized by the thermal gravimetric (TG) and differential thermal gravimetric (DTG), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM), respectively. Both TG and DTG curves of the precursor precipitates show that no further mass loss and thermal effect were observed above the temperature 450°C. The FT-IR results indicated that the precursor of ZnO nanoparticles was zinc hydroxy carbonate. The XRD results show that the prepared ZnO nanoparticles were pure wurtzite structures. TEM photographs demonstrated that ZnO nanoparticles were of a pseudo-spherical shape with an average crystal size of about 65 nm.

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16

Lemos, A. F., A. H. S. Rebelo, J. H. G. Rocha, and José Maria F. Ferreira. "A Method for Simultaneously Precipitating and Dispersing Nano-Sized Calcium Phosphate Suspensions." Key Engineering Materials 284-286 (April 2005): 67–70. http://dx.doi.org/10.4028/www.scientific.net/kem.284-286.67.

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Stable and relatively concentrated aqueous suspensions of nano-sized stoichiometric hydroxyapatite could be prepared by a precipitation method in the presence of suitable surface active agent (SAA). The method includes the precipitation, vacuum filtration and washing of the precipitated powders, followed by re-dispersion. It could be concluded that the added amount of the SAA should be enough to cover the primary particles surface, and that washing should be better carried out using a SAA solution. The method developed enables the precipitation of the powders and the preparation of suspensions, while significantly shortening the overall time required for colloidal processing consuming.

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17

Kim, Kyung Nam, and Yong Do Kim. "Synthesis of Calcium Carbonate Particles Modified by Coating with Nickel Precursor." Materials Science Forum 486-487 (June 2005): 546–49. http://dx.doi.org/10.4028/www.scientific.net/msf.486-487.546.

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CaCO3 powders were prepared by the homogeneous precipitation method using CaCl2, urea as the starting materials. Uniform CaCO3(calcite, aragonite, vaterite) powders were obtained by various conditions. The surfaces of CaCO3 powders were modified by coating them with a lithium precursor using two different precipitation techniques: homogeneous decomposition of precipitating agents(urea, NaHCO3, NH4HCO3) and forced hydrolysis in pure water. Selecting the Ni(NO3)26H2O and urea(or NaHCO3, NH4HCO3) as Ni-source and precipitating agent respectively, the NiO could be uniformly coated on the CaCO3 powder in the aqueous system. The coating NiO layer dominated the surface properties of the coated lime powders. Calcination of these nickel hydroxide crystals in air at 500°C transformed them into NiO.

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18

Kurylenko, Viktor, Nataliia Tolstopalova, Olga Sanginova, and Tetiana Obushenko. "Review of fluorine removal methods from aqueous solutions." Proceedings of the NTUU “Igor Sikorsky KPI”. Series: Chemical engineering, ecology and resource saving, no. 1 (March 31, 2023): 52–69. http://dx.doi.org/10.20535/2617-9741.1.2023.276447.

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Introduction. The high-quality water conditioning problem does not disappear from the agenda of chemists, biologists, and ecologists. Fluoride content is an important water quality indicator, as fluoride can have both positive and negative effects on the human body. The purpose of this work is a critical review of methods for removing fluorine compounds from natural surface and underground waters, and from wastewater. An analysis of 77 modern scientific articles was performed, the advantages and disadvantages of such methods as precipitation and co-precipitation, methods using semipermeable membranes, dialysis and electrocoagulation, ion exchange and sorption methods were determined. Results and discussion. It was determined that the precipitation and co-precipitation methods use of chemical reagents, so they are quite expensive, and the sediments formed in the defluoridation process are subject to disposal. Membrane methods do not require the chemicals addition, are highly efficient and easy to control, but at the same time, defluoridation removes other ions that are present in water and are important indicators of the drinking water quality. A significant disadvantage of membrane methods is that a major amount of brine is formed during the treatment process, which also creates a disposal problem. Dialysis and electrocoagulation methods have the advantages and disadvantages of electrochemical methods: they provide high quality water, but this is accompanied by increased electricity consumption, the use of limited service life electrodes. Along with the high degree of water defluoridation, ion exchange methods are characterized by high cost, as well as significant water consumption for such technological processes as loosening, regeneration and washing of ion-exchange resins. An additional problem is the flushing and rinsing wastewater disposal. Sorptive fluoride removal is the most promising and widely used method. The main advantages include the method simplicity, non-deficiency and availability of sorbents. Effective sorbents are natural minerals, foremost, clinoptilolite, nepheline, low-quality phosphorites and apatites, glauconite, basalt tuffs, which are abundant in the subsoil of Ukraine. Unlike other methods, the spent materials are easily disposed of, or can be used as additives in the production of silicate materials, for example, bricks. Conclusions. Promising fluoride removal methods are sorption methods using natural mineral and modified sorbents.

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Wang, Jing, Hua Min Kou, Yu Bai Pan, and Jing Kun Guo. "Febrication of MWNTs Composites with In Situ Precipitation Method." Solid State Phenomena 121-123 (March 2007): 135–38. http://dx.doi.org/10.4028/www.scientific.net/ssp.121-123.135.

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In this article stable multi-walled carbon nanotubes (MWNTs) aqueous suspension with a 1.0 wt.% concentration was obtained with a very small quantity of dispersant. Precursor of ceramics were synthesized in the suspension and densely deposited on the surface of MWNTs successfully by a simple and effective in-situ precipitation method. The most important advantage for the in-situ composite method is to make MWNTs homogeneously distributed in the matrix. The fully dense compacts were obtained by spark-plasma-sintering (SPS) the in-situ precipitated composite powders at temperature 200 oC lower than that of composite powders made from the traditional mixing method. Furthermore, the microstructure and the mechanical property of the composites are much better than that of traditional method. The in-situ precipitation could be a promising method to fabricate CNTs composites of ceramics matrix especially those hard to sinter.

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Sutiyono, S., Luluk Edahwati, Dyah Suci Perwitasari, Stefanus Muryanto, J. Jamari, and Anatasius P. Bayuseno. "Synthesis and Characterisation of Struvite Family Crystals by An Aqueous Precipitation Method." MATEC Web of Conferences 58 (2016): 01006. http://dx.doi.org/10.1051/matecconf/20165801006.

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21

Unuma, Hidero. "Ceramic Coatings Deposited from Aqueous Solutions." Solid State Phenomena 124-126 (June 2007): 527–30. http://dx.doi.org/10.4028/www.scientific.net/ssp.124-126.527.

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This paper reviews novel techniques developed in our laboratory to deposit ceramic thin films from aqueous solutions. All the techniques are based on the heterogeneous nucleation and growth phenomenon; ceramic precipitates are prone to be formed preferentially on substrate/solution interfaces when the rate of the formation of the precipitates is appropriately controlled. In “oxidative soak coating” method, metal ions with a lower valence state are oxidized in homogeneous solutions to those with a higher valence state; thereby coatings of SnO2, MnO2, CeO2, Co3O4 and Fe3O4 have been deposited. In “ligand decomposition” method, ligands of an indium peroxo- complex are decomposed to promote spontaneous hydrolysis of the indium ion; thereby In2O3 coating has been deposited. In “enzyme-assisted precipitation” method, precipitant of metal ions is supplied by urease immobilized on a substrate to promote local deposition of ceramics on the substrate, by which hydroxyapatite coating has been rapidly deposited. The control of the rate of the precipitation reactions is the most important parameter. Some properties of the resultant coatings are also presented.

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22

Sigwadi, Rudzani A., Sipho E. Mavundla, Nosipho Moloto, and Touhami Mokrani. "Synthesis of zirconia-based solid acid nanoparticles for fuel cell application." Journal of Energy in Southern Africa 27, no. 2 (July 20, 2016): 60. http://dx.doi.org/10.17159/2413-3051/2016/v27i2a1342.

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Zirconia nanoparticles were prepared by the precipitation and ageing methods. The precipitation method was performed by adding ammonium solution to the aqueous solution of zirconium chloride at room temperature. The ageing method was performed by leaving the precipitate formed in the mother liquor in the glass beaker for 48 hours at ambient temperatures. The nanoparticles from both methods were further sulphated and phosphated to increase their acid sites. The materials prepared were characterised by X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), Brunauer-EmmettTeller (BET), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) methods. The XRD results showed that the nanoparticles prepared by the precipitation method contained mixed phases of tetragonal and monoclinic phases, whereas the nanoparticles prepared by ageing method had only tetragonal phase. The TEM results showed that phosphated and sulphated zirconia nanoparticles obtained from the ageing method had a smaller particle size (10–12 nm) than the nanoparticles of approximately 25–30 nm prepared by precipitation only. The BET results showed that the ZrO2 nanoparticles surface area increased from 32 to 72 m2/g when aged.

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Ungureanu, Dan Nicolae, Nicolae Angelescu, Adrian Catangiu, Daniela Avram, Florina Violeta Anghelina, and Ileana Nicoleta Popescu. "Synthesis of Ceramic Biomaterials Based on Calcium and Phosphorus from Aqueous Solutions." Scientific Bulletin of Valahia University - Materials and Mechanics 17, no. 17 (October 1, 2019): 23–26. http://dx.doi.org/10.2478/bsmm-2019-0014.

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AbstractThis paper presents the most used processes for the synthesis of hydroxyapatite from aqueous solutions: chemical precipitation, the hydrothermal process and the sol-gel method. The experimental part includes the synthesis of hydroxyapatite by chemical precipitation. The obtained results confirm the obtaining of a ceramic with a high purity and a high degree of crystallization.

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Kim, So Jin, Won Kyu Han, Sung Goon Kang, Min Su Han, and Young Hun Cheong. "Formation of Lanthanum Hydroxide and Oxide via Precipitation." Solid State Phenomena 135 (February 2008): 23–26. http://dx.doi.org/10.4028/www.scientific.net/ssp.135.23.

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Lanthanum hydroxide and oxide were prepared by the precipitation method in an aqueous medium at room temperature. The precipitate was examined using thermal analysis, X-ray diffraction and Scanning Electron Microscopy to investigate the phase evaluation and the thermal transformation by decomposition. The as-precipitated powder from the precipitation method was hexagonal La(OH)3. The lanthanum hydroxide was decomposed to oxide in two-steps as La(OH)3 → LaOOH + H2O and 2LaOOH → La2O3 + H2O.

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Wan, Jingwei, Lu ding, Tao Wu, Xuebing Ma, and Qian Tang. "Facile one-pot fabrication of magnetic nanoparticles (MNPs)-supported organocatalysts using phosphonate as an anchor point through direct co-precipitation method." RSC Adv. 4, no. 72 (2014): 38323–33. http://dx.doi.org/10.1039/c4ra04720f.

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Novel MNP-supported organocatalysts were prepared by one-pot co-precipitation and surface modification using phosphonate as an anchor point, and exhibited excellent performance in aqueous asymmetric aldol reactions.

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Kokila, Karuppannan, Nagaraj Elavarasan, and Venugopal Sujatha. "Diospyros montana leaf extract-mediated synthesis of selenium nanoparticles and their biological applications." New Journal of Chemistry 41, no. 15 (2017): 7481–90. http://dx.doi.org/10.1039/c7nj01124e.

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Yin, Guangzhong, Donglin Zhao, Ye Ren, Lianwei Zhang, Zheng Zhou, and Qifang Li. "A convenient process to fabricate gelatin modified porous PLLA materials with high hydrophilicity and strength." Biomaterials Science 4, no. 2 (2016): 310–18. http://dx.doi.org/10.1039/c5bm00414d.

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SABERYAN, KAMAL, SADEGH FIROOZI, AMIN MORADMAND, and ALI REYHANI. "SYNTHESIS OF MO-CO ALLOY NANOPOWDER BY CO-PRECIPITATION METHOD FOLLOWED BY H2 REDUCTION." International Journal of Modern Physics: Conference Series 05 (January 2012): 142–50. http://dx.doi.org/10.1142/s201019451200195x.

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Cobalt-Molybdenum alloy nanopowder has magnetic properties and is used as catalyst for production of carbon nanotubes. Properties of this nanopowder depend on, for example, its size, morphology and internal residual stress. Synthesis of nanopowder of Molybdenum-Cobalt alloy by co-precipitation in an aqueous media using NH 4 OH as precipitating agent followed by calcination and reduction was investigated. The synthesis was started by dissolving salts of Cobalt and Molybdenum in water. A suspension of alumina or silica powders was used as a bed for precipitation. The effect of bed materials on size and morphology of the precipitate was investigated. The particles observed with scanning electron microscope possess a spherical shape and a needle shape for the samples participated on alumina and silica beds, respectively. XRD analysis of the calcined precipitate showed the formation of mixed oxide of CoMoO 4 as well as single oxides of Co 3 O 4 and MoO 3. Particle size of the precipitate observed with transmission electron microscope was about 100 nm. Finally, the powders were reduced by hydrogen gas in a tubular furnace to prepare metallic nanopowder with composition of Co 3 Mo .

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Li, Leilei, Long Chen, Yuehua Wen, Tengfei Xiong, Hong Xu, Wenfeng Zhang, Gaoping Cao, Yusheng Yang, Liqiang Mai, and Hao Zhang. "Phenazine anodes for ultralongcycle-life aqueous rechargeable batteries." Journal of Materials Chemistry A 8, no. 48 (2020): 26013–22. http://dx.doi.org/10.1039/d0ta08600b.

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A nano-phenazine@Ketjen black anode was achieved by the in situ dissolution–precipitation method, possessing the cycle life of 100 000 times due to the stabilities and insolubilities of phenazine and its reduction products in aqueous electrolytes.

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Zhao, Ruihong, Fen Guo, Yongqi Hu, and Huanqi Zhao. "Self-assembly synthesis of organized mesoporous alumina by precipitation method in aqueous solution." Microporous and Mesoporous Materials 93, no. 1-3 (July 2006): 212–16. http://dx.doi.org/10.1016/j.micromeso.2006.02.024.

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Sumrunronnasak, Sarocha, Narong Chanlek, and Nuttaporn Pimpha. "Improved CeCuOx catalysts for toluene oxidation prepared by aqueous cationic surfactant precipitation method." Materials Chemistry and Physics 216 (September 2018): 143–52. http://dx.doi.org/10.1016/j.matchemphys.2018.05.006.

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Wu, Yu-Chun, Yu-Chen Chaing, Chi-Yuen Huang, Sea-Fue Wang, and Hui-Yu Yang. "Morphology-controllable Bi2O3 crystals through an aqueous precipitation method and their photocatalytic performance." Dyes and Pigments 98, no. 1 (July 2013): 25–30. http://dx.doi.org/10.1016/j.dyepig.2013.02.006.

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Carrillo, Wilman, David Lara, Edgar Vilcacundo, Cristian Carrillo, Monica Silva, Mario Alvarez, and Cecilia Carpio. "OBTENTION OF PROTEIN CONCENTRATE AND POLYPHENOLS FROM MACADAMIA (MACADAMIA INTEGRIFOLIA) WITH AQUEOUS EXTRACTION METHOD." Asian Journal of Pharmaceutical and Clinical Research 10, no. 2 (February 1, 2017): 138. http://dx.doi.org/10.22159/ajpcr.2017.v10i2.14808.

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Objective: The aim of this study was to obtain protein concentrates from macadamia using alkaline pH at different pHs of precipitation with water to analyze the protein isolates using the Native-PAGE, SDS-PAGE electrophoresis and RP-UHPLC methods.Materials & Methods: Macadamia protein concentrates were obtained using the isoelectric precipitation method at different pHs using water as solvent. Proteins were analyzed using the Native-PAGE, SDS-PAGE electrophoresis and RP-UHPLC methods.Results: A yield of 36.57±0.17a of protein concentrate of defatted macadamia flour at pH 6.0 with a 51.564% of protein was obtained using the Dumas method. Polypeptides profile was identified in the 11-63 kDa range. Total polyphenols content was high at pH 5.0 with a value of 367,340 mg GAE equivalents / 100 g.Conclusions: Macadamia seed is a good source of proteins. Native-PAGE, SDS-PAGE and RP-UHPLC are good methods to identify the macadamia protein isolate in presence of water.

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Kim, Kyung Nam, Dae Yong Shin, Se Gu Son, and Yong Do Kim. "Synthesis of Calcium Carbonate from Calcium Chlorine Solution Using Homogeneous Precipitation Method." Materials Science Forum 486-487 (June 2005): 542–45. http://dx.doi.org/10.4028/www.scientific.net/msf.486-487.542.

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Calcium carbonate(CaCO3) was synthesized from aqueous CaCl2 solution, using the homogeneous precipitation technique, which uses the hydrolysis of urea. The effects of reaction conditions on the morphology of CaCO3 were examined at 50-90°C. Particle size of CaCO3 decreases, as the concentrations of urea and [Ca2+] are increased. Calcite is produced more, as the concentration of [Ca2+] is increased. Method to stir the reaction solution affects significantly the particle size and morphology of CaCO3. Uniform needle-like aragonite particles were obtained, when left at 90°C for 4hours without stirring.

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Chen, Yu, Yun-fei Liu, and Hui-min Tan. "Preparation of macroporous cellulose-based superabsorbent polymer through the precipitation method." BioResources 3, no. 1 (February 5, 2008): 247–54. http://dx.doi.org/10.15376/biores.3.1.247-254.

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Superabsorbent polymer was prepared by graft polymerization of acrylic acid onto the chain of carboxymethyl cellulose. This superabsorbent polymer was further treated by the solvent precipitation method. We found that the water absorption rate of the treated polymer was greatly increased and the microstructure of the treated polymer was changed from close-grained structures to loose macropores. The swelling processes of the polymers before and after modification fit first-order dynamic processes. The amount of the residual acrylic acid was detected through high performance liquid chromatography (HPLC) with aqueous solution of MOPS of 0.02mol/L (pH=5.70) as the mobile phase. It was found that the amount of the residual acrylic acid decreased from 83.8×10-4 % to 6.7×10-4 % after treatments.

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Aktaş, Pelin. "Synthesis of BaTi5O11 by an aqueous co-precipitation method via a stable organic titanate precursor." Journal of the Serbian Chemical Society 86, no. 4 (2021): 415–27. http://dx.doi.org/10.2298/jsc200706014a.

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BaTi5O11 has been widely researched due to its unique microwave properties. Conventionally, it is challenging to obtain this compound as a single phase. The BaTi5O11 was synthesized via a co-precipitation technique using an aqueous solution of titanium(IV)(triethanolaminato) isopropoxide, barium nitrate and ammonia as precursors, which are stable in aqueous media. The phase evolution, purity, and structure were identified by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy analysis. The desired BaTi5O11 structure was obtained by calcination at 900?C. Furthermore, the structure was characterized by TGA, FT-IR and Raman studies. The study showed that the particles were between 80 and 120 nm in size and the average crystallite size was determined from the Scherrer formula as 68.1 nm at 900?C.

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Estay, Humberto, Lorena Barros, and Elizabeth Troncoso. "Metal Sulfide Precipitation: Recent Breakthroughs and Future Outlooks." Minerals 11, no. 12 (December 8, 2021): 1385. http://dx.doi.org/10.3390/min11121385.

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The interest in metal sulfide precipitation has recently increased given its capacity to efficiently recover several metals and metalloids from different aqueous sources, including wastewaters and hydrometallurgical solutions. This article reviews recent studies about metal sulfide precipitation, considering that the most relevant review article on the topic was published in 2010. Thus, our review emphasizes and focuses on the overall process and its main unit operations. This study follows the flow diagram definition, discussing the recent progress in the application of this process on different aqueous matrices to recover/remove diverse metals/metalloids from them, in addition to kinetic reaction and reactor types, different sulfide sources, precipitate behavior, improvements in solid–liquid separation, and future perspectives. The features included in this review are: operational conditions in terms of pH and Eh to perform a selective recovery of different metals contained in an aqueous source, the aggregation/colloidal behavior of precipitates, new materials for controlling sulfide release, and novel solid–liquid separation processes based on membrane filtration. It is therefore relevant that the direct production of nanoparticles (Nps) from this method could potentially become a future research approach with important implications on unit operations, which could possibly expand to several applications.

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Muche, Dereck N. F., Flavio L. Souza, and Ricardo H. R. Castro. "New ultrasonic assisted co-precipitation for high surface area oxide based nanostructured materials." Reaction Chemistry & Engineering 3, no. 3 (2018): 244–50. http://dx.doi.org/10.1039/c7re00183e.

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Liu, Lei, Zhaojie Cui, Qianchi Ma, Wei Cui, and Xu Zhang. "One-step synthesis of magnetic iron–aluminum oxide/graphene oxide nanoparticles as a selective adsorbent for fluoride removal from aqueous solution." RSC Advances 6, no. 13 (2016): 10783–91. http://dx.doi.org/10.1039/c5ra23676b.

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Halaciuga, Ionel, Sylas LaPlante, and Dan V. Goia. "Method for preparing dispersed crystalline copper particles for electronic applications." Journal of Materials Research 24, no. 10 (October 2009): 3237–40. http://dx.doi.org/10.1557/jmr.2009.0390.

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Dispersed crystalline copper particles were prepared by reacting aqueous dispersions of CuCl with ferrous citrate. We report that the Fe(II) citrate complex can reduce rapidly and completely cuprous chloride to metallic copper and propose a mechanism for the reaction observed. By changing the precipitation conditions, copper particles with sizes varying from 250 nm to 2.0 µm were obtained. The method described represents a simple and versatile approach for preparing copper powders for electronic applications.

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Dai, Qiguang, Shuxing Bai, Hua Li, Wei Liu, Xingyi Wang, and Guanzhong Lu. "Template-free and non-hydrothermal synthesis of CeO2nanosheets via a facile aqueous-phase precipitation route with catalytic oxidation properties." CrystEngComm 16, no. 42 (2014): 9817–27. http://dx.doi.org/10.1039/c4ce01436g.

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Petal and belt-like CeO₂nanosheets are synthesized using an aqueous phase precipitation method under template-free and non-hydrothermal conditions and exhibit excellent catalytic oxidation performance.

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Nam, Gyutae, and Meilin Liu. "(Invited) Wastewater Derived Cathode Materials for Aqueous Zn-Batteries." ECS Meeting Abstracts MA2022-02, no. 1 (October 9, 2022): 32. http://dx.doi.org/10.1149/ma2022-02132mtgabs.

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While lithium-ion batteries (LIBs) have been widely used for portable devices and electric vehicles, it is highly desirable to develop safer and less expensive batteries as alternative to LIBs. In this regard, zinc (Zn) batteries have attracted much attention because of their excellent safety and low cost. However, one of the challenges is to develop cost-effective and highly efficient cathode materials for Zn-ion batteries (ZIBs) based on transition metal oxides. It would be more economical to recycle transition metals in order to reduce the fabrication cost. Co-precipitation method is widely used for synthesis of LIBs cathode materials, and large amount of wastewater would be produced during co-precipitation and battery production process. In this presentation, we will report a facile and general process for fabrication of cathode materials for aqueous Zn-ion batteries (ZIBs) by reusing wastewater from co-precipitation method. We have selected manganese rich phases with different ratio of nickel to cobalt precursors from co-precipitation wastewater, followed by a simple ball milling process, resulting in metal-hydroxide cathode materials (Mn0.6Ni0.1Co0.3OxHy, Mn0.6Ni0.2Co0.2OxHy, and Mn0.6Ni0.3Co0.1OxHy). Among them, the Mn0.6Ni0.1Co0.3OxHy cathode (with mass loading of 15 mg cm-2) exhibits an initial capacity of 263 mAh g-1 at a current density of 0.1 A g-1, as evaluated in an mixture electrolyte (2M ZnSO4 and 0.1M MnSO4). Furthermore, operando X-ray absorption spectroscopy analysis has revealed the role of each transition metal ions during insertion and desertion of Zn ions. It is found that the ratio of Ni to Co significantly influences ZIBs performances, providing important insight into rational design of more efficient cathode materials for aqueous Zn-ion batteries. Figure 1

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Suntako, Rudeerat. "Influence of Polymer Additive on Synthesis of ZnO Nanoparticle by Precipitation Method." Applied Mechanics and Materials 481 (December 2013): 60–65. http://dx.doi.org/10.4028/www.scientific.net/amm.481.60.

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The effects of polyacrylic acid (PAA) as an additive on ZnO nanoparticles synthesized by precipitation method is investigated. It is found that ZnO synthesized exhibits a crystalline structure with hexagonal structure of the wurtzite. Primary size of ZnO nanoparticles synthesized can be controlled by PAA concentrations. Increasing of PAA concentration provide small particle size. Addition of 1 wt% PAA can be obtained the average primary size around 20 nm. Additionally, ZnO synthesized using PAA exhibits zeta potential value higher than ZnO synthesized without PAA. With the increasing PAA concentration, Zeta potential value increase. It indicates that ZnO synthesized using 0.5-1 wt% PAA can be well-dispersed in aqueous system and promote highly stable suspension.

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Tien, Nguyen Anh, Truong Chi Hien, and Bùi Xuân Vương. "Synthesis of holmium orthoferrite nanoparticles by the co-precipitation method at high temperature." Metallurgical and Materials Engineering 27, no. 3 (June 11, 2021): 321–29. http://dx.doi.org/10.30544/612.

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Holmium orthoferrite HoFeO3 nanoparticles were synthesized by a simple co-precipitation method via the hydrolysis of Ho (III) and Fe (III) cations in boiling water with 5% aqueous ammonia solution. After annealing the precipitate at 750 and 850 °C for 1 hour, the single-phase HoFeO3 product formed with particle size < 50 nm. The synthesized nanopowders are paramagnetic materials with remanent magnetization Mr < 0.01 emu·g-1, the coercive force Hc = 20÷21 Oe, and magnetization Ms ~ 2.73 emu·g-1 at 300 K in a maximum field of 16,000 Oe.

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Baster, Dominika, Emad Oveisi, Pierre Mettraux, Surbhi Agrawal, and Hubert H. Girault. "Sodium chromium hexacyanoferrate as a potential cathode material for aqueous sodium-ion batteries." Chemical Communications 55, no. 97 (2019): 14633–36. http://dx.doi.org/10.1039/c9cc06350a.

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Akhtar, Khalida, Ikram Ul Haq, and Uzma Hira. "Synthesis and Characterization of Uniform Zirconia Particles by Homogeneous Precipitation Method." High Temperature Materials and Processes 32, no. 4 (August 16, 2013): 391–95. http://dx.doi.org/10.1515/htmp-2012-0156.

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AbstractColloidal spherical particles (micrometer size) of zirconia were synthesized at 50°C by homogeneous precipitation method from aqueous solutions, containing appropriate amounts of zirconium chloride, hydrochloric acid, potassium sulphate and urea. Results revealed that reactants concentration significantly affected characteristics of the precipitated solids, which ranged from gel to dispersion of discrete particles. Size uniformity in the resulted particles was obtained only under limited conditions. SEM images revealed that particles of zirconia obtained under the described experimental conditions have spherical morphology, which maintained their original shape after calcination at 700°C. Selected powders were also characterized with XRD, TGA/DTA, and FT-IR techniques. XRD results showed that as-prepared and calcined powders were crystalline. We believe that our method is simple and has the potential for further tailoring of the particles characteristics. Work is in progress in our laboratory in developing Cu-ZrO2 metal matrix composite coating on steel substrate with better resistant properties than simple Cu electroplating.

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Beutler, J. A., T. C. McKee, R. W. Fuller, M. Tischler, J. H. Cardellina, K. M. Snader, T. G. McCloud, and M. R. Boyd. "Frequent Occurrence of HIV-Inhibitory Sulphated Polysaccharides in Marine Invertebrates." Antiviral Chemistry and Chemotherapy 4, no. 3 (June 1993): 167–72. http://dx.doi.org/10.1177/095632029300400306.

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Aqueous extracts of many marine invertebrates have exhibited some activity in the National Cancer Institute's primary screen for anti-HIV cytopathicity. Using a variety of techniques, including gel permeation, size exclusion and ion exchange chromatography, toluidine blue metachromicity, 13C-NMR spectroscopy and combustion analyses, we have determined that this activity is largely due to sulphated polysaccharides. Because of the wide occurrence of this class of compounds in these organisms we sought a method for the rapid dereplication of sulphated polysaccharides. It was critical that the method selected for dereplication allow differentiation of anionic polysaccharides from other AIDS-antiviral chemotypes. After evaluating a variety of methods, we found that the most efficient strategy appeared to be precipitation of the polysaccharide fraction from aqueous ethanolic solutions of the crude aqueous extracts.

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MONTAZERI-POUR, M., and A. ATAIE. "LOW TEMPERATURE CRYSTALLIZATION OF BARIUM FERRITE NANO-PARTICLES VIA CO-PRECIPITATION METHOD USING DIETHYLENE GLYCOL." International Journal of Modern Physics B 22, no. 18n19 (July 30, 2008): 3144–52. http://dx.doi.org/10.1142/s0217979208048036.

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Nano-crystalline particles of barium ferrite have been prepared by co-precipitation route using aqueous and non-aqueous solutions of iron and barium chlorides with a Fe/Ba molar ratio of 11. Water and a mixture of diethylene glycol and water with volume ratio of 3:2 were used as solvents in the process. Co-precipitated powders were annealed at various temperatures for 1 h. Phase composition of the samples was evaluated by XRD while their morphology was studied by TEM and SEM techniques. The XRD results showed that the single phase barium ferrite obtained at 750°C when diethylene glycol/water mixture was used as a solvent. This temperature increased to 900°C when the starting materials dissolved in water. Nano-size particles of barium ferrite with mean particle size of almost 50 and 80 nm were observed in the SEM micrographs of the samples synthesized in diethylene glycol/water solution after annealing at 750°C and 800°C for 1 h, respectively. The corresponding mean crystallite size measured by TEM for sample annealed at 800°C was 40 nm.

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Wei, Rong Hui, Kai Du, Xiao Yang Gong, Qing Dong Chen, and Hai Bin Yang. "Preparation and Optical Properties of Carbon Fiber/ZnO Core-Shell Structure by a Simple Method." Advanced Materials Research 557-559 (July 2012): 236–39. http://dx.doi.org/10.4028/www.scientific.net/amr.557-559.236.

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A core-shell structure material, carbon fiber/ZnO was prepared by a surface modification precipitation process in aqueous solution. The structure, absorptive properties and photoluminescence properties of the composites were investigated. Results showed that the energy bandgap of samples calculated from the absorptive spectra was about 3.30eV. The green emission peak of the samples was ascribed to the oxygen vacancies.

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Minato, Haruka, Masaki Murai, Takumi Watanabe, Shusuke Matsui, Masaya Takizawa, Takuma Kureha, and Daisuke Suzuki. "The deformation of hydrogel microspheres at the air/water interface." Chemical Communications 54, no. 8 (2018): 932–35. http://dx.doi.org/10.1039/c7cc09603h.

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The deformation of soft hydrogel microspheres (microgels) adsorbed at the air/water interface was investigated for the first time using large poly(N-isopropyl acrylamide)-based microgels synthesized by a modified aqueous precipitation polymerization method.

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