Journal articles: 'Colloidal silica gel'

1

Williamson, B. J., J. J. Wilkinson, P. F. Luckham, and C. J. Stanley. "Formation of coagulated colloidal silica in high-temperature mineralizing fluids." Mineralogical Magazine 66, no. 4 (August 2002): 547–53. http://dx.doi.org/10.1180/0026461026640048.

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AbstractRecent experimental studies have suggested that colloidal silica can form in high-T (300 to >700°C) hydrothermal fluids (Wilkinson et al., 1996). Natural evidence in support of this was found by Williamson et al. (1997) who proposed a colloidal (gel) silica origin for <50 μm irregularly-shaped inclusions of quartz contained in greisen topaz from southwest England. Confocal and microprobe studies, presented here, strengthen this argument although rather than forming a gel in the hydrothermal fluid, it is suggested that the colloidal silica aggregated as a viscous coagulated colloid, with much of its volume (<10 to 30 vol.%) consisting of metal (mainly Fe) -rich particles. This is evident from the largely solid nature of metal-rich shrinkage bubbles contained at the margins of the inclusions of quartz which shows that the material forming the inclusions contained much less liquid than would be expected in a silica gel. These findings may have important implications for models of ore formation since the precipitation of a coagulated colloid could inhibit hydrothermal fluid transport and cause co-deposition of silica and entrained ore-forming elements. The mode of formation of the colloidal silica and further implications of the study are discussed.

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Jurinak, J. J., and L. E. Summers. "Oilfield Applications of Colloidal Silica Gel." SPE Production Engineering 6, no. 04 (November 1, 1991): 406–12. http://dx.doi.org/10.2118/18505-pa.

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Jin, Weifeng, Rongzhong Chen, Xin Wang, and Zehai Cheng. "Effect of Wood Fiber on the Strength of Calcareous Sand Rapidly Seeped by Colloidal Silica." MATEC Web of Conferences 275 (2019): 03006. http://dx.doi.org/10.1051/matecconf/201927503006.

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Silica nano-particles are suspended in the colloidal silica and can be induced to gradually gel after the PH value changes. Thus colloidal silica can be utilized to rapidly seep through loose calcareous sand, and the silicon gel is gradually formed to bond sand particles. However, based on observation by scanning electron microscope(SEM), there are a lot of microcracks in the silica gel, which reduces the strength of the sand-gel composite. Therefore, in order to suppress crack growth, wood fibers are dispersed in the colloidal silica which still can seep through calcareous sand. 18 silicon-gel stabilized sand samples were prepared for tri-axial tests, where the concentration of colloidal silica is 20%, and wood fiber concentrations are 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, respectively. The results show that:(1) there exists an optimum ratio of wood fiber to colloidal silica, that is, as the concentration of wood fiber increases, the strength represented by the peak value of deviator stress rises first and then falls; (2) there are opposite trends between the two strength parameters, internal friction angle and cohesion, that is, when the wood fiber concentration is 0.04%, the cohesion reaches the maximum value and the internal friction angle reaches the minimum value; (3) The photos by SEM show that, there are wood fibers on the inner wall of the crack in the silica gel, which may reduce the extent of crack propagation and contribute to the strength of stabilized sand samples.

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Gu, Shuang Na, Ying Shi, Liang Yong Wang, Wei Li Liu, and Zhi Tang Song. "Modification of Colloidal Silica with Sodium Aluminate." Applied Mechanics and Materials 468 (November 2013): 39–42. http://dx.doi.org/10.4028/www.scientific.net/amm.468.39.

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Colloidal silica modified by sodium aluminate was examined. The particle size of Al-modified colloidal silica was slightly increased with increase of the sodium aluminate concentration, but colloidal silica may aggregate or gel under high concentration. Zeta potential was more negative and thermal stability was significantly improved through modification. The Al-modified colloidal silica was highly stable at pH 3-6.

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5

Kawakita, Hidetaka, Kaori Yokoyama, Shohei Esaki, Shintaro Morisada, and Keisuke Ohto. "Separation of Colloidal Particle Using Elastic-Gel-Packed Column." MATEC Web of Conferences 333 (2021): 04003. http://dx.doi.org/10.1051/matecconf/202133304003.

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Polymerized spherical gel (46 μm) was packed in a column to permeate silica particle suspension for the separation due to their differences of sizes. The elastic gel in the bottom domain of column deformed more because the pressure of the fluid flow suppressed the packed gel layer, that is, the formed gaps among the gels at the bottom domain had the smaller ‘pore’, resulting in filtering the smaller-size of the particles at the bottom of the column. The larger the size of silica particle, the upper the filtered domain in the column. To elute the filtered silica particle, the gel layer was compacted and restored by on-off of the fluid flow, to open the gaps in the gel layer repeatedly, demonstrating that the elution percentage of silica particle was gradually increased by the repeated on-off permeation of water.

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Kawakita, Hidetaka, Kaori Yokoyama, Shohei Esaki, Shintaro Morisada, and Keisuke Ohto. "Separation of Colloidal Particle Using Elastic-Gel-Packed Column." MATEC Web of Conferences 333 (2021): 04003. http://dx.doi.org/10.1051/matecconf/202133304003.

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Polymerized spherical gel (46 μm) was packed in a column to permeate silica particle suspension for the separation due to their differences of sizes. The elastic gel in the bottom domain of column deformed more because the pressure of the fluid flow suppressed the packed gel layer, that is, the formed gaps among the gels at the bottom domain had the smaller ‘pore’, resulting in filtering the smaller-size of the particles at the bottom of the column. The larger the size of silica particle, the upper the filtered domain in the column. To elute the filtered silica particle, the gel layer was compacted and restored by on-off of the fluid flow, to open the gaps in the gel layer repeatedly, demonstrating that the elution percentage of silica particle was gradually increased by the repeated on-off permeation of water.

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7

Mun, Byung Bae, Ho Kun Kim, and Jin Koo Park. "Chemical Durability and Anti-Microbial Property of Silver-Doped Colloidal Silica." Solid State Phenomena 124-126 (June 2007): 1209–12. http://dx.doi.org/10.4028/www.scientific.net/ssp.124-126.1209.

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Silver-doped silica gel was prepared by the reaction of colloidal silica and AgNO3. In the synthetic process, aluminum ions promote the chemical durability of silver-doped silica gel with dramatically decreasing the elusion of silica ions at the aqueous solution. Especially, aluminum ions induce slow release silver ion of silver-doped silica gel over a long period of time. Also, antimicrobial effects evaluated using a shake flask method resulted in a disinfection ratio of Staphylococcus aureus(ATCC 6538) and Escherichia coli(ATCC 25922) of over 99.9%, indicating high anti-microbial properties.

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Chao, Chin-Hsiao, and Hong-Yang Lu. "Crystallization of Na2O-doped colloidal gel-derived silica." Materials Science and Engineering: A 282, no. 1-2 (April 2000): 123–30. http://dx.doi.org/10.1016/s0921-5093(99)00758-3.

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9

Wang, Li Hsing, and Bor Jou Tsai. "The sintering and crystallization of colloidal silica gel." Materials Letters 43, no. 5-6 (May 2000): 309–14. http://dx.doi.org/10.1016/s0167-577x(99)00279-7.

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10

Shin, Yong Tak, Min Ji Lee, Kyung Sook Cho, and Ki Chang Song. "Effect of Colloidal Silica on the Photochromic Properties of Hard Coating Films Prepared by Sol-Gel Method." Korean Chemical Engineering Research 49, no. 5 (October 1, 2011): 535–40. http://dx.doi.org/10.9713/kcer.2011.49.5.535.

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11

Cai, Yun Gao, Qing Lan Ma, and Yuan Ming Huang. "Effect of Sodium Chloride on the Sol-Gel Synthesized Silica Colloidal Particles." Solid State Phenomena 181-182 (November 2011): 417–21. http://dx.doi.org/10.4028/www.scientific.net/ssp.181-182.417.

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The effect of sodium chloride on the sol-gel synthesized silica colloidal particles has been investigated. The silica colloidal particles in the size range of 420-800 nm were synthesized from the hydrolysis and condensation of tetraethyl orthosilicate by varying the amount of sodium chloride from 15 to 30 mg while keeping the tetraethyl orthosilicate (20 ml), ethanol (125 ml), ammonia (6 ml) and distilled water (18 ml) fixed. Scanning electron microscopy (SEM) was employed to analyze the morphology of the synthesized silica particles. Our results demonstrated that: (1) sticky and spongy silica spheroids were resulted if the amount of sodium chloride was less than 15 mg; (2) spherical silica particles were resulted with good monodispersity when the amount of sodium chloride was in the range of 22-24 mg; and (3) silica spheres were obtained but with a wide size distribution when the amount of sodium chloride was more than 26 mg.

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12

Díaz-Rodríguez, J. A., V. M. Antonio-Izarraras, P. Bandini, and J. A. López-Molina. "Cyclic strength of a natural liquefiable sand stabilized with colloidal silica grout." Canadian Geotechnical Journal 45, no. 10 (October 2008): 1345–55. http://dx.doi.org/10.1139/t08-072.

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This paper summarizes the experimental results of a series of cyclic simple shear tests on liquefiable silty sand with and without sample improvement with colloidal silica grout. The objective of the paper is to evaluate the effectiveness of colloidal silica grouting in reducing the liquefaction potential of natural silty sand. Colloidal silica was selected as a stabilizing material due to its low viscosity, wide range of gel times, nontoxicity, and low cost. The soil tested in this experimental program is a poorly graded sand with 11.5% of nonplastic silt from the Port of Lázaro Cárdenas, México. Colloidal silica treated and untreated sand specimens show different pore pressure response and deformation behavior under cyclic loading in simple shear tests. The results indicate that, for a given initial relative density and initial effective vertical stress, liquefiable silty sand specimens stabilized with colloidal silica grout generally exhibit significant gain in liquefaction resistance compared with untreated specimens. It was also found that the colloidal silica grout reduces considerably the rates of pore pressure generation and shear strain of the silty sand specimens subjected to cyclic loading.

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13

Oen, I. S., and C. Kieft. "A metacolloidal dendrite-rich Bi-Ni-Co quartz vein, Pozoblanco, Spain." Mineralogical Magazine 57, no. 387 (June 1993): 241–47. http://dx.doi.org/10.1180/minmag.1993.057.387.06.

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AbstractA Bi-Ni-Co vein in the contact zone of a granite near Pozoblanco, Córdoba, Spain, shows a zoned structure with mm-thin quartz wall zones, up to 20 cm thick Bi-rich quartz zones, and a few cm thick quartz-bismuth transition zones grading into a central quartz vug zone. The Bi-rich zones show textures indicating a metacolloidal origin from a silica gel enriched in adsorbed Bi: (1) globular and chain aggregates of fine-granular allotriomorphic quartz represent morphological relics of a globulated silica gel; (2) quartz rosettes, chain rosettes and stringer-combs radiating from the quartz globules and chains represent crystallised silica gel matrix; (3) crack fillings of quartz, gersdorffite and platy bismuth dendrites represent precipitates of metal-saturated dilute hydrosols filling shrinkage cracks in the desiccating and crystallising gel; (4) quartz spherocrystals in rosettes and combs are clouded with colloidal particles inherited from the silica gel; (5) unsupported wall rock inclusions represent inclusions in a viscous silica gel precursor covering fissure walls. The thin wall zones are quartz fillings of cracks between shrinking gel and walls. The transition and vug zones are recrystallised colloidal silica crusts precipitated by fissure-filling rest-solutions. Tree-like bismuth-gersdorffite dendrites in the transition zones are precipitates of metal-rich solutions infiltrating from the Bi-rich zones into the recrystallising silica crusts. The pre-concentration of metals in silica gels explains the dendrite formation without assuming abnormally high metal concentrations in transporting solutions or long range diffusion processes.

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14

Krisnandi, Yuni K., Indah R. Saragi, Riwandi Sihombing, Rizki Ekananda, Indah P. Sari, Benjamin E. Griffith, and John V. Hanna. "Synthesis and Characterization of Crystalline NaY-Zeolite from Belitung Kaolin as Catalyst for n-Hexadecane Cracking." Crystals 9, no. 8 (August 4, 2019): 404. http://dx.doi.org/10.3390/cryst9080404.

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Crystalline sodium Y (NaY) zeolite has been synthesized using alternative natural source of aluminate and silicate, extracted from natural Belitung kaolin. Prior to use, the natural kaolin was pretreated to obtain fragmented metakaolin and extracted silica. Synthesis was conducted with the addition of NaY gel (two types of NaY seeds were used, prepared from colloidal sillica or sodium silica water) using hydrothermal method for 21 h at 100 °C. The characterization on the as-synthesized zeolites confirmed that the one prepared using colloidal silica-seed has closer structure similarity to NaY zeolite that was synthesized using pro analysis silicate and aluminate sources. Thus, the rest of the synthesis of NaY was carried out using colloidal silica-NaY seed. The NaY zeolites then were converted to HY, through ammonium-exchange followed by calcination, to be tested as cracking catalysts using n-hexadecane as a probe molecule. It shows that HY from metakaolin and extracted silica gives high performance, i.e., n-hexadecane conversion of 58%–64%, also C5-C12 percentage yield and selectivity of 56%–62% and 98%. This work has shown the potential to utilize kaolin as alternative silicate aluminate sources for crystalline zeolite synthesis and to obtain inexpensive and environmentally friendly catalyst materials.

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15

Scherer, C. P., and C. G. Pantano. "Titania-silica glasses using a colloidal sol-gel process." Journal of Non-Crystalline Solids 82, no. 1-3 (June 1986): 246–55. http://dx.doi.org/10.1016/0022-3093(86)90138-9.

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16

Afsharimani, Nasima, Alicia Durán, Dušan Galusek, and Yolanda Castro. "Hybrid Sol–Gel Silica Coatings Containing Graphene Nanosheets for Improving the Corrosion Protection of AA2024-T3." Nanomaterials 10, no. 6 (May 29, 2020): 1050. http://dx.doi.org/10.3390/nano10061050.

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In the present work, nanostructured graphene nanosheets were added to hybrid silica sols and deposited on aluminium alloy A2024-T3 to study the effect on the corrosion behaviour. Sols were prepared using tetraethyl-orthosilicate (TEOS), 3-glycidoxypropyl-trimethoxysilane (GPTMS) and a colloidal silica suspension (LUDOX) as silica precursors with adding chemically modified graphene nanosheets (GN-chem). The graphene nanosheets were modified through a straightforward and simple hydrothermal approach and then, dispersed into a silica sol (SiO2/GN-chem). ATR-FTIR was used to optimize the silica sol–gel synthesis and to confirm the cross-linking of the silica network. The corrosion behaviour of the SiO2/GN-chem coatings was also analysed by electrochemical measurement (potentiodynamic polarization) in 0.05 M NaCl solution. The results showed that the incorporation of modified graphene nanosheets into hybrid silica sol–gel coatings affected the corrosion properties of the substrates. An improvement in the corrosion resistance was observed likely due to the enhanced barrier property and hydrophobic behaviour obtained by incorporation of GN-chem and colloidal silica nanoparticles.

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Chen, Gengbiao, and Zhiwen Liu. "Effect of Hydrophobic Silica Nanochannel Structure on the Running Speed of a Colloidal Damper." Applied Sciences 11, no. 15 (July 24, 2021): 6808. http://dx.doi.org/10.3390/app11156808.

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A colloidal damper (CD) can dissipate a significant amount of vibrations and impact energy owing to the interface power that is generated when it is used. It is of great practical significance to study the influence of the nanochannel structure of hydrophobic silica gel in the CD damping medium on the running speed of the CD. The fractal theory was applied to observe the characteristics of the micropore structure of the hydrophobic silica gel by scanning electron microscopy (SEM), the primary particles were selected to carry out fractal analysis, and the two-dimensional fractal dimension of the pore area and the tortuous fractal dimension of the hydrophobic silica gel pore structure were calculated. The fractal percolation model of water in hydrophobic silica nanochannels based on the slip theory could thus be obtained. This model revealed the relationship between the micropore structure parameters of the silica gel and the running speed of the CD. The CD running speed increases with the addition of grafted molecules and the reduction in pore size of the silica gel particles. Continuous loading velocity testing of the CD loaded with hydrophobic silica gels with different pore structures was conducted. By comparing the experimental results with the calculation results of the fractal percolation model, it was determined that the fractal percolation model can better characterize the change trend of the CD running velocity for the first loading, but the fractal dimension was changed from the second loading, caused by the small amount of water retained in the nanochannel, leading to the failure of fractal characterization.

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Hidayat, Muhammad Iqbal, Muhammad Adlim, Ilham Maulana, and Muhammad Zulfajri. "Immobilization of Silver Nanoparticles on Chitosan-Coated Silica-Gel-Beads and the Antibacterial Activity." Key Engineering Materials 892 (July 13, 2021): 36–42. http://dx.doi.org/10.4028/www.scientific.net/kem.892.36.

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Silver nanoparticles (Ag0) have attracted the most attention due to their broad antimicrobial application and outstanding activity. The silver nanoparticles are usually in colloidal form, then immobilization the colloid onto solid support is still interesting to explore. In this work, a new method for silver colloidal nanoparticle immobilization on silica gel beads (SiG), which was then symbolized as Ag0-[chi-SiG] was conducted and characterized successfully. The finding proved that SiG must be coated with three chitosan film layers to give stable support for silver nanoparticles. This coating method caused the chitosan completely covered SiG, and the chitosan film provides coordination bonding for silver ions. The most appropriate solvent for silver ion impregnation on the surface of chi-SiG is methanol compared to other solvents. Tungsten lamp as the photo-irradiation, which is low cost and environmentally friendly has been proven effective for silver ion reduction, as shown by silver metal colloid UV-Vis surface plasmon resonance at 400-700 nm. Ag0-[chi-SiG] showed the antibacterial properties of inhibiting the growth Staphylococcus aureus and Escherichia coli; then it provides the potential application for antibacterial filter material. According to the weight comparison between antibacterial standard and Ag content, then Ag0-[chi-SiG] has two and five times higher of exhibiting zone for each bacteria.

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Park, Hoy Yul, Dong Pil Kang, In Hye Myung, and Seog Young Yoon. "Properties of Coating Films Synthesized from Nano Colloidal Silica and Alkoxy Silanes." Materials Science Forum 510-511 (March 2006): 222–25. http://dx.doi.org/10.4028/www.scientific.net/msf.510-511.222.

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Colloidal silica/silane sol solutions were prepared in variation with the ratio of silane to colloidal silica. Such sol solutions were synthesized from colloidal silica/tetramethoxysilane (TMOS)/methyltrimethoxysilane(MTMS). Sol solutions were prepared by sol-gel reaction through two step reactions. To understand their physical and chemical properties, dip coating of sol solutions was performed on the glass substrates. Contact angle and thickness of coating films increased with increasing the amount of MTMS. The surface free energy of coating films decreased with increasing amount of MTMS. Coating films were stable until 550°C. Thermal degradation temperature of coating films decreased with increasing amount of MTMS. Plastic hardness decreased with increasing amount of MTMS. Elastic portion increased with increasing amount of MTMS.

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Kerch, Helen M., Gabrielle G. Long, Susan Krueger, Andrew J. Allen, Rosario Gerhardt, and Frederick Cosandey. "Characterization of Porosity Over Many Length Scales: Application to Colloidal Gels." Journal of Materials Research 14, no. 4 (April 1999): 1444–54. http://dx.doi.org/10.1557/jmr.1999.0195.

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Processing-microstructure relationships in a silica gel system, based on mixtures of colloidal sol and soluble potassium silicate, have been studied. Quantitative microstructural information regarding colloidal cluster sizes, size distributions, surface areas, and pore-size distribution from the nanopore range to the macropore range was determined via small-angle scattering and transmission electron microscopy. The colloid cluster size distribution varies systematically, with gels fabricated with the least colloidal fraction possessing the most polydisperse microstructure. It is shown that the porosity over the entire range can be tailored by selecting the appropriate starting chemistry; under the same pH conditions, the ratio of the two silicate ingredients controls the average size, the polydispersity of sizes, and the connectivity of the pores. A population of fine (2 nm) uniformly dispersed nanopores, which result from leaching, is responsible for large increases in surface area. The leaching process can be controlled by the surrounding macropore void size, which determines alkali transport. The product material consists of 85% large, open pores, with fine pores within the gel skeleton, making this gel an ideal candidate for controlled-porosity applications such as catalyst supports and magnetic composites.

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Cho, Y. S. "Fabrication Of Colloidal Clusters Decorated With Dye Molecules For Potential Application As Photonic Molecules." Archives of Metallurgy and Materials 60, no. 2 (June 1, 2015): 1221–25. http://dx.doi.org/10.1515/amm-2015-0102.

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AbstractIn this study, colloidal clusters decorated with fluorescent dyes were fabricated by evaporation-driven self-assembly using emulsion droplets as confining geometries. Silica microspheres were synthesized by Stober method followed by the modification with dye molecules through additional surface sol-gel reaction for the formation of thin silica shell. The surface of the resultant dye-doped silica microspheres was modified with hydrophobic silane coupling agent to disperse the particle suspension in organic solvent such as hexane. The fluorescent silica microspheres were self-assembled inside oil-in-water emulsions by evaporation-driven self-assembly for the formation of colloidal clusters, potentially applicable for photonic molecules. The clusters with fluorescent emission were observed using confocal microscope.

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Shull, R. D., H. M. Kerch, and J. J. Ritter. "Magnetic properties of colloidal silica: Potassium silicate gel/iron nanocomposites." Journal of Applied Physics 75, no. 10 (May 15, 1994): 6840–42. http://dx.doi.org/10.1063/1.356802.

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23

Yamamoto, K., T. Iwatsubo, Ken-ichi Saitoh, and T. Moriuchi. "Simulation of Water Flow in a Coated Nano Pore by a Molecular Dynamics." Advances in Science and Technology 57 (September 2008): 73–79. http://dx.doi.org/10.4028/www.scientific.net/ast.57.73.

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This paper presents on a new damping element called the colloidal damper which is used a principle of surface extension force in nano pore. The direction acting of the surface extension force of water in hydrophobic nano pore is different in pressurization and decompressurization processes [1,2]. This principle is applied to a damping element. The nano pore is constructed by silica gel. A silica gel ball of 100-200 micrometer dia. has many nano pores of 5-20 nanometer dia. in it [3,4]. The coated spherical silica gel and water are inserted in a piston - cylinder unit in order to work as a damper. If compression and decompression forces are added to the piston - cylinder unit (damper), water flows into and moves out the nano pore under balance of pressure. A contact angle of compression formed by the hydrophobic nano pore and water is larger than that of decompression. This difference of the contact angle produces a damping energy. In this paper, behavior of water in the pore of silica gel is investigated using the molecular dynamics. Dissipation energy of the colloidal damper is concerned with the contact angles of water in the pore. So the contact angles are calculated for changing parameters, i.e. size of the pore, length of the hydrophobic material, velocity (pressure) of water flows into the pore. Then these results are compared with the experimental ones.

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Fu, Ming, Ji Zhou, Bo Li, Qun Fang Xiao, Yue Hui Wang, and Long Tu Li. "Optical Properties of Nanocrystalline Ag Doped Silica Inverse Opals." Key Engineering Materials 336-338 (April 2007): 555–57. http://dx.doi.org/10.4028/www.scientific.net/kem.336-338.555.

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Nanocrystalline Ag doped silica inverse opals were prepared by a sol-gel chemistry method via templating of polystyrene colloidal crystals. The ordered structures of colloidal crystal templates and inverse opals are characterized by scanning electron microscopy. Ag nanocrystals size is estimated as 20~30nm by Scherrer Formula from X-ray diffraction. The color and the stop band of the inverse opals are characterized by transmission spectrum. And five emission peaks of the nanocrystalline silver clusters are observed from fluorescence spectrum.

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Shalviri, Alireza, Avinash C. Sharma, Dipak Patel, and Amyn Sayani. "Low-Surfactant Microemulsions for Enhanced Topical Delivery of Poorly Soluble Drugs." Journal of Pharmacy & Pharmaceutical Sciences 14, no. 3 (August 2, 2011): 315. http://dx.doi.org/10.18433/j38p4v.

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Purpose: To develop and characterize low-surfactant microemulsion (ME) gels to enhance topical delivery of poorly soluble drugs. Method: Five low surfactant ME formulations were manufactured following the construction of pseudo-ternary phase diagrams. The MEs were screened for their ability to dissolve a poorly soluble new chemical entity (Model Drug X). Various viscosity imparting agents like Carbopol 934, Colloidal Silica, HPMC K100M, Lubrajel NP, and Xanthan Gum were evaluated for the manufacture of these ME gels. Each ME gel was then further evaluated for physical stability, including assessing rheological profiles. In vitro release profiles were also determined and compared to a conventional ointment. Results: Three of the five low surfactant MEs developed (ME1, ME4 and ME5) were capable of dissolving Model Drug X up to 14 fold higher than the conventional ointment formulation. ME1 and ME4 gels comprising Xanthan gum or Carbopol 934 were physically stable, while ME5 gel was stable only with Colloidal Silica. The ME5 gel with Colloidal Silica showed an irreversible increase in its elastic modulus when exposed to high temperature, indicating that the formulation would be less suitable for commercial use. The Xanthan Gum and Colloidal Silica gels yielded significantly higher release rates (8 - 10 fold) compared to a conventional ointment and formulations containing Carbopol 934. The significant difference in drug release rates between Xanthan Gum and Carbopol 934 indicated that choice of viscosity imparting agent played an important role in governing drug release from ME gels. Conclusion: ME gels were developed with low surfactant concentrations and improved formulation characteristics, which increased the solubility and subsequent release of a poorly soluble drug. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.

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Nisticò, Roberto, Paola Avetta, Paola Calza, Debora Fabbri, Giuliana Magnacca, and Dominique Scalarone. "Selective porous gates made from colloidal silica nanoparticles." Beilstein Journal of Nanotechnology 6 (November 4, 2015): 2105–12. http://dx.doi.org/10.3762/bjnano.6.215.

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Highly selective porous films were prepared by spin-coating deposition of colloidal silica nanoparticles on an appropriate macroporous substrate. Silica nanoparticles very homogenous in size were obtained by sol–gel reaction of a metal oxide silica precursor, tetraethyl orthosilicate (TEOS), and using polystyrene-block-poly(ethylene oxide) (PS-b-PEO) copolymers as soft-templating agents. Nanoparticles synthesis was carried out in a mixed solvent system. After spin-coating onto a macroporous silicon nitride support, silica nanoparticles were calcined under controlled conditions. An organized nanoporous layer was obtained characterized by a depth filter-like structure with internal porosity due to interparticle voids. Permeability and size-selectivity were studied by monitoring the diffusion of probe molecules under standard conditions and under the application of an external stimulus (i.e., electric field). Promising results were obtained, suggesting possible applications of these nanoporous films as selective gates for controlled transport of chemical species in solution.

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Kayode, Sodipo Bashiru, and Azlan Abdul Aziz. "Physico-Chemical Properties of Silica Coated Superparamagnetic Magnetite Nanoparticles Synthesized by Non-Seeded Process." Advanced Materials Research 1107 (June 2015): 267–71. http://dx.doi.org/10.4028/www.scientific.net/amr.1107.267.

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The science of core-shell nanoparticles requires investigation into several physical and chemical properties of the composite nanoparticles. Unlike the conventional sol-gel or the reverse microemulsion micelle method, we presented here a non-seeded process of encapsulating superparamagnetic magnetite nanoparticles (SPMN) with silica. Physico-chemical analysis of the product was used to confirm the result of the coating procedure. Colloidal suspension of SPMN and silica nanoparticles were synthesised through coprecipitation method and modified Stöber method respectively. Afterwards, both colloidal suspensions of SPMN and silica nanoparticles were sonicated to encapsulate the SPMN with silica. Elemental mapping of the composite particles with electron spectroscopy imaging (ESI) confirmed the core-shell micrograph of the SPMN and silica. The X-ray diffraction pattern (XRD) showed the silica shell to be in amorphous form. FTIR analysis further confirmed the chemical properties of the product to be silica coated SPMN.

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Kim, Bo-Hye, Myong-Shik Cho, So-Yeun Kim, You-Jeong Kim, Hee-Gweon Woo, Do-Heyoung Kim, Honglae Sohn, and Andhong Li. "Dry Sol–Gel Polycondensation of Hydrosilanes to Organosilicas Catalyzed by Colloidal Nickel Nanoparticles." Journal of Nanoscience and Nanotechnology 7, no. 11 (November 1, 2007): 3964–68. http://dx.doi.org/10.1166/jnn.2007.084.

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The dry sol–gel polycondensation at toluene in ambient air atmosphere of p-X-C6H4SiH3 (X = H, CH3, CH3O, F, Cl) to silica p-X-C6H4SiO1.5 in high yield, catalyzed by colloidal nickel nanoparticles in-situ generated from nickelocene(II), nickel(II) acetate, and bis(1,5-cyclooctadiene)nickel(0), is described. Similar catalytic activities were observed for the catalysts. Similarly, the dry sol–gel polyco-condensation p-X-C6H4SiH3 (X = CH3, CH3O, F, Cl):C6H4SiH3 (9:1 mole ratio) at toluene in ambient air atmosphere of was performed to yield co-silicas (p-X-C6H4SiO1.5)9(p-X-C6H4SiO1.5)1 in high yield using nickelocene. The co-gels with higher molecular weights and TGA residue yield were obtained when compared to the homogels. The highest yield, molecular weight, polydispersity index, and TGA residue yield were obtained for p-Cl-C6H4SiH3. Some degree of unreacted Si—H bonds still remained in the gel matrix because of steric bulkiness. All the insoluble gels adopt an amorphous structure with a smooth surface. A plausible mechanism for the dry sol–gel reaction was suggested.

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KANEKO, HIDEO, and SADAO HIROTA. "Dielectric studies on emulsion of aqueous agarose gel in hydrophobic colloidal silica-oil gel." CHEMICAL & PHARMACEUTICAL BULLETIN 33, no. 5 (1985): 1775–81. http://dx.doi.org/10.1248/cpb.33.1775.

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Park, Hoy Yul, Moon Kyong Na, Seog Young Yoon, and Seong Soo Park. "Properties of Coating Films Synthesized from Colloidal Silica and Methyltrimethoxysilane." Materials Science Forum 544-545 (May 2007): 1037–40. http://dx.doi.org/10.4028/www.scientific.net/msf.544-545.1037.

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Colloidal silica/methyltrimethoxysilane (MTMS) sol solutions were prepared in variation with the ratio of MTMS to colloidal silica. Sol solutions were prepared by sol-gel reaction. To understand their physical and chemical properties, dip coating of sol solutions was performed on the glass substrates. The state of coating films was investigated in variation with the amount of MTMS and reaction time. The contact angle and thickness of coating films increased with an increasing amount of MTMS. The surface roughness of coating films decreased with an increasing amount of MTMS. Coating films were stable until 550°C. Thermal degradation temperature of coating films decreased with an increasing amount of MTMS.

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Yu, Yang Yen, Wen Chen Chien, and Tsung Wei Tsai. "Microstructure and Properties of Polyimide /Monodispersed Colloidal Silica Hybrid Films Prepared by Sol–Gel Process." Advanced Materials Research 47-50 (June 2008): 650–53. http://dx.doi.org/10.4028/www.scientific.net/amr.47-50.650.

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In this study, the polyimide-silica hybrid thin films, 6FDA-6FpDA-4ABA/SiO2 (FS0-FS50) were prepared from the 12nm colloidal silica and polyimide bearing acid endgroups. During the preparation, without any additional coupling agents or chelating ligands were used. The strong interactions between carboxylic acid coordinating with silica were believed to prevent the macrophase separation. TGA analysis showed that the thermal decomposition temperatures (Td) incresased with increasing the silica content. UV-VIS spectra showed that the cutoff wavelength of prepared hybrid films could be tunable through the silica content. The n&k analysis showed that the refractive index (n) of PS hybrid films were in the range of 1.575-1.479, which could be controlled by the silica content. The extinction coefficients (k) are almost zero in the wavelength range of 300–900 nm, indicating the prepared hybrid films have an excellent optical transparency in the UV and visible region. TEM images showed that the particle size of silica in the hybrid thin films could be effectively controlled. The results of SEM and AFM showed that all the prepared hybrid films have a good planarity. It demonstrated that the prepared polyimide-silica hybrid thin films have an excellent film formability and planarity.

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Munakata, Hirokazu, Hiroto Chiba, Kaoru Dokko, Jun Ichi Hamagami, Takashi Takei, and Kiyoshi Kanamura. "Enhancement on Proton Conductivity of Three-Dimensionally Ordered Macroporous Silica Membrane by Surface Sulfonation." Key Engineering Materials 301 (January 2006): 143–46. http://dx.doi.org/10.4028/www.scientific.net/kem.301.143.

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A new proton-conducting membrane was prepared consisting of uniformly macroporous silica matrix and a proton-conducting gel polymer, 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS). Three-dimensionally ordered macroporous silica membrane was fabricated by use of a colloidal template method with mono-dispersed polystyrene beads. Surface sulfonation of the pores in the silica matrix was performed by using 1,3-propanesultone. The sulfonated silica matrix exhibited about 400 times higher proton conductivity than unmodified one. The proton conductivity of the composite membrane was also successfully enhanced by using the sulfonated silica matrix.

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Keshavarz, Bavand, Donatien Gomes Rodrigues, Jean-Baptiste Champenois, Matthew G. Frith, Jan Ilavsky, Michela Geri, Thibaut Divoux, Gareth H. McKinley, and Arnaud Poulesquen. "Time–connectivity superposition and the gel/glass duality of weak colloidal gels." Proceedings of the National Academy of Sciences 118, no. 15 (April 9, 2021): e2022339118. http://dx.doi.org/10.1073/pnas.2022339118.

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Colloidal gels result from the aggregation of Brownian particles suspended in a solvent. Gelation is induced by attractive interactions between individual particles that drive the formation of clusters, which in turn aggregate to form a space-spanning structure. We study this process in aluminosilicate colloidal gels through time-resolved structural and mechanical spectroscopy. Using the time–connectivity superposition principle a series of rapidly acquired linear viscoelastic spectra, measured throughout the gelation process by applying an exponential chirp protocol, are rescaled onto a universal master curve that spans over eight orders of magnitude in reduced frequency. This analysis reveals that the underlying relaxation time spectrum of the colloidal gel is symmetric in time with power-law tails characterized by a single exponent that is set at the gel point. The microstructural mechanical network has a dual character; at short length scales and fast times it appears glassy, whereas at longer times and larger scales it is gel-like. These results can be captured by a simple three-parameter constitutive model and demonstrate that the microstructure of a mature colloidal gel bears the residual skeleton of the original sample-spanning network that is created at the gel point. Our conclusions are confirmed by applying the same technique to another well-known colloidal gel system composed of attractive silica nanoparticles. The results illustrate the power of the time–connectivity superposition principle for this class of soft glassy materials and provide a compact description for the dichotomous viscoelastic nature of weak colloidal gels.

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Na, Moon Kyong, Myeong Sang Ahn, and Hoy Yul Park. "Properties of Sol-Gel Coating Film from Colloidal Silica-Silane Sol." Materials Science Forum 544-545 (May 2007): 813–16. http://dx.doi.org/10.4028/www.scientific.net/msf.544-545.813.

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Two kinds of colloidal silica(CS)/silane sol solutions were prepared. Two sol solutions are involved with the kinds of silane such as methyltrimethoxysilane(MTMS) and -Glycidoxypropyl trimethoxysilane(ETMS) using LS CS. MTMS was added to two sol solutions. Whether ETMS was added or not, two kinds of sol solutions were synthesized. Using two kinds of sol solutions, sol-gel coating films were formed on glass substrates via dip-coating process. Here, seasoning effect of for enhancing properties of sol-gel coating layer on glass was investigated while such sol-gel solutions were left for 7days. Also, their properties such as surface free energy, roughness, thermal property, potential hardness and elastic portion were characterized in order to understand the effect of addition of ETMS. In this case of LS/MTMS sol, the coating film had low surface free energy and more enhanced flat surface than that of the case of LS/MTMS/ETMS sol. ETMS forms hydrophilic hydroxyl group in sol solution, then surface free energy of LS/MTMS/ETMS coating film increased. In the beginning of reaction sol solution seemed to be unstable, but 4days later their coating film properties such as surface free energy and roughness enhanced. The elastic portion of coating films obtained from LS/MTMS/ETMS sol increased with addition of ETMS, but thermal stability decreased.

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Tamar, Yair, and Yoel Sasson. "Examination of the regime controlling sol–gel based colloidal silica aggregation." Journal of Non-Crystalline Solids 380 (November 2013): 35–41. http://dx.doi.org/10.1016/j.jnoncrysol.2013.08.018.

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36

ONO, Shigeki. "Particle Size Distribution Analysis of Colloidal Silica by Gel Permeation Chromatography." KOBUNSHI RONBUNSHU 49, no. 9 (1992): 759–63. http://dx.doi.org/10.1295/koron.49.759.

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37

Gonçalves, M. Clara. "Sol-gel Silica Nanoparticles in Medicine: A Natural Choice. Design, Synthesis and Products." Molecules 23, no. 8 (August 13, 2018): 2021. http://dx.doi.org/10.3390/molecules23082021.

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Silica is one of the most abundant minerals in the Earth’s crust, and over time it has been introduced first into human life and later into engineering. Silica is present in the food chain and in the human body. As a biomaterial, silica is widely used in dentistry, orthopedics, and dermatology. Recently amorphous sol-gel SiO2 nanoparticles (NPs) have appeared as nanocarriers in a wide range of medical applications, namely in drug/gene target delivery and imaging diagnosis, where they stand out for their high biocompatibility, hydrophilicity, enormous flexibility for surface modification with a high payload capacity, and prolonged blood circulation time. The sol-gel process is an extremely versatile bottom-up methodology used in the synthesis of silica NPs, offering a great variety of chemical possibilities, such as high homogeneity and purity, along with full scale pH processing. By introducing organic functional groups or surfactants during the sol-gel process, ORMOSIL NPs or mesoporous NPs are produced. Colloidal route, biomimetic synthesis, solution route and template synthesis (the main sol-gel methods to produce monosized silica nanoparticles) are compared and discussed. This short review goes over some of the emerging approaches in the field of non-porous sol-gel silica NPs aiming at medical applications, centered on the syntheses processes used.

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Zhapekova, А. О., N. N. Mofa, B. Elouadi, R. S. Iminova, А. Е. Bakkara, and Z. A. Mansurov. "MECHANOCHEMICAL AND ULTRASONIC TREATMENT – A CONTROLLED METHOD FOR FORMING THE STRUCTURE AND PROPERTIES OF NANOCOMPOSITE GEL SYSTEMS." SERIES CHEMISTRY AND TECHNOLOGY 2, no. 446 (April 12, 2021): 36–44. http://dx.doi.org/10.32014/2021.2518-1491.24.

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In this work, the preparation of colloidal systems with microcrystalline cellulose as a gelling agent and silica powder as a filler was considered. By mechanochemical and ultrasonic treatment of a filler made of silicon dioxide and a colloidal base, varying the constituent ingredients, one can purposefully influence the structure of the system and regulate the properties of the resulting compositions. It is shown that the introduction of a filler made of highly dispersed silicon dioxide into a gel system based on cellulose, modified by ultrasonic treatment (UST) with acid additives, provides both acceleration of the gelation process and stabilization of the state of the obtained colloidal composition. As a result of UST, a nanostructured colloidal homogeneous system is formed.

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Tian, Hong, Dong Jiang Yang, and Yao Xu. "Single-Layer Silica Anti-Reflective Films Modified with Polytetramethylene Glycol." Materials Science Forum 663-665 (November 2010): 969–73. http://dx.doi.org/10.4028/www.scientific.net/msf.663-665.969.

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Single-layer silica films modified with polytetramethylene glycol (PTMEG) were prepared via sol-gel process in the presence of NH4OH as catalyst. Compared with the pure SiO2 coating, the hybrid films possessed higher lased-induced damage threshold (LDT). The characterization results from AFM and TEM indicated that the introduction of PTMEG molecules changes the structure of the colloidal silica matrix, which directly resulted in the improvement of the transparency and LDT.

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40

Lazareva, S. V., N. V. Shikina, L. E. Tatarova, and Z. R. Ismagilov. "Synthesis of High-Purity Silica Nanoparticles by Sol-Gel Method." Eurasian Chemico-Technological Journal 19, no. 4 (December 29, 2017): 295. http://dx.doi.org/10.18321/ectj677.

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Colloidal silica (silica sol) nanoparticles were synthesized by ammonia- and hydrochloric acid-catalyzed hydrolysis of tetraethoxysilane with subsequent condensation and polymerization. Silica particles with the size of 12‒160 nm were obtained at different temperatures and ratios of the initial reactants and studied by means of TEM, AFM, IR spectroscopy and zeta-potential measurements. The reaction conditions providing the minimum particle size in the final product of the most complete hydrolysis were determined. At pH above 8.5, an increase in the SiO2 content of the sol to 23 wt.% did not change the particle size. At a low (~ 1.8 wt.%) SiO2 content of the sol, a wide variation in pH also did not exert a significant effect on the particle size. Stability of the silica sols synthesized in an alkaline medium was enhanced by the replacement of alcohol with water during evaporation at pH 8.5‒9.5. The possibility to produce silica sols with the required characteristics (particle size, pH, stability, purity, and SiO2 content in an aqueous or alcohol medium) makes them applicable in various industries.

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41

Bondarenko, Lyubov, Erzsébet Illés, Etelka Tombácz, Gulzhian Dzhardimalieva, Nina Golubeva, Olga Tushavina, Yasuhisa Adachi, and Kamila Kydralieva. "Fabrication, Microstructure and Colloidal Stability of Humic Acids Loaded Fe3O4/APTES Nanosorbents for Environmental Applications." Nanomaterials 11, no. 6 (May 27, 2021): 1418. http://dx.doi.org/10.3390/nano11061418.

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Nowadays, numerous researches are being performed to formulate nontoxic multifunctional magnetic materials possessing both high colloidal stability and magnetization, but there is a demand in the prediction of chemical and colloidal stability in water solutions. Herein, a series of silica-coated magnetite nanoparticles (MNPs) has been synthesized via the sol-gel method with and without establishing an inert atmosphere, and then it was tested in terms of humic acids (HA) loading applied as a multifunctional coating agent. The influence of ambient conditions on the microstructure, colloidal stability and HA loading of different silica-coated MNPs has been established. The XRD patterns show that the content of stoichiometric Fe3O4 decreases from 78.8% to 42.4% at inert and ambient atmosphere synthesis, respectively. The most striking observation was the shift of the MNPs isoelectric point from pH ~7 to 3, with an increasing HA reaching up to the reversal of the zeta potential sign as it was covered completely by HA molecules. The zeta potential data of MNPs can be used to predict the loading capacity for HA polyanions. The data help to understand the way for materials’ development with the complexation ability of humic acids and with the insolubility of silica gel to pave the way to develop a novel, efficient and magnetically separable adsorbent for contaminant removal.

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42

Huang, Yi, and Motoyoshi Kobayashi. "Direct Observation of Relaxation of Aqueous Shake-Gel Consisting of Silica Nanoparticles and Polyethylene Oxide." Polymers 12, no. 5 (May 16, 2020): 1141. http://dx.doi.org/10.3390/polym12051141.

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Controlling the rheological property of suspensions consisting of colloidal particles and polymers is necessary in industry. Especially, gels induced by shear (shake-gel) are interesting phenomena in rheological field. To gain insight into the shake-gel phenomena of the aqueous suspensions of silica nanoparticles and poly(ethylene oxide) (PEO) and its temporal change, we observed the state transition and measured the viscosity of the silica-PEO suspensions. Our results showed that PEO dose, pH, and molecular weight of PEO influence the state of suspension greatly, and revealed the differences of the suspension states, namely, cloudy, permanent gel, shake-gel, and high viscosity sol. We found that the relaxation time from shake-gel to flowable sol increases to the maximum and decreases again with increasing PEO dose. Shake-gels at pH 8.4 relaxed more slowly than at pH 9.4, and shake-gel did not form at pH above 10 in most of cases, indicating high pH inhibits the formation of shake-gels. PEO of molecular weight of 1000 and 4000 kDa easily bonds more silica nanoparticles by bridging and results in the formation of gels with more stable polymer networks. PEO of molecular weight of 1000 and 4000 kDa also led to longer relaxation time of the silica-PEO suspensions from gel to sol.

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43

Suzuki, Daisuke, Kiyoshi Shibata, Akira Tsuchida, and Tsuneo Okubo. "Thermo-sensitive colloidal crystals composed of monodisperse colloidal silica- and poly(N-isopropyl acrylamide) gel spheres." Colloid and Polymer Science 293, no. 10 (July 2, 2015): 2763–69. http://dx.doi.org/10.1007/s00396-015-3661-1.

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Yu, Yang Yen, Wen Chen Chien, and Chiung Lin Lai. "Preparation and Patterning of Optical Hybrid Thin Films Based on Photosensitive Polyimide and Monodispersed Colloidal Silica." Advanced Materials Research 47-50 (June 2008): 654–57. http://dx.doi.org/10.4028/www.scientific.net/amr.47-50.654.

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In this study, optical hybrid thin films were prepared from photosensitive poly(4,4-(hexafluoroisopropyl- idenediphthalic anhydride)-co-oxydianiline) (6FDA-ODA)/MDAE and monodispersed colloidal silica with a coupling agent. It was a combination of the sol–gel reaction, thermal polymerization and spin coating. The coupling agents were 3-methacryloxypropyl trimethoxysilane (MPTMS) or (4-vinylphenethyl)trimethoxysilane (VPTMS). The silica content in the hybrid thin films was varied from 0 to 8.6wt%. The coupling agent and the silica domain were designed primarily for reducing the volume shrinkage and enhancing the thermal properties, respectively. The retention of MDAE in the prepared hybrid films is supported by X-ray photoelectron spectroscopy (XPS). The silica domain significantly enhanced the thermal properties of the prepared hybrid films in comparison with parent fluorinated polyimide. The prepared hybrid materials also exhibited reduced refractive index by increasing the silica content. The results of SEM showed the prepared photosensitive hybrid materials could obtain lithographical patterns with a good resolution. These results indicated that the newly prepared photosensitive polyimide/colloidal silica hybrid thin films had potential applications for optical devices.

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45

Jirathampradhab, Taksorn, Siraprapa Lhosupasirirat, Pisist Kumnorkaew, Thananan Akhadejdamrong, Pichet Rojanapitayakorn, and Toemsak Srikhirin. "Study the Effect of Coating Thickness from Silica Nanocomposite Deposited on Poly(Methyl Methacrylate) Sheets via Spray Coating Technique." Materials Science Forum 895 (March 2017): 79–82. http://dx.doi.org/10.4028/www.scientific.net/msf.895.79.

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The development of hard coating based on colloidal silica nanoparticles on polymethyl methacrylate (PMMA) sheet was reported. The colloidal silica was surface-modified with methyltrimethoxysilane (MTMS) and formulated to hard coating solution via sol-gel process. The hard coating solution was applied to PMMA surface by spray deposition technique. Spraying process was carried out from spray nozzle outlet diameter of 0.35 mm and air compress pressure at 0.2 MPa with nozzle to substrate distance at 10 cm. The different coating thicknesses were obtained by adjusting the amount of coating applied. The optimal coating thickness that gives the highest pencil-hardness at 7H and 100% adhesion for adhesion tape test is 10 μm.

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Vinokurov, Vladimir, Andrei Novikov, Valentina Rodnova, Boris Anikushin, Mikhail Kotelev, Evgenii Ivanov, and Yuri Lvov. "Cellulose Nanofibrils and Tubular Halloysite as Enhanced Strength Gelation Agents." Polymers 11, no. 5 (May 24, 2019): 919. http://dx.doi.org/10.3390/polym11050919.

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Silica gels are widely employed in water shutoff services, making them an essential tool in oil well management. Silica nanoparticles may serve as a strengthening additive for polymer hydrogels. In this study, we look at this statement from a different angle: What additives could be used to increase the strength of silica gels? Colloidal silica gels were prepared with various additives, and gel strength was measured by a Veiler–Rebinder apparatus. We found that cellulose nanofibrils considerably increase the gel strength (from 20–25 to 35–40 kPa), which is comparable with the industrial anionic polymer Praestol 2540. Cellulose nanofibrils can be produced from cheap industrial-grade cellulose with low-cost industrial chemicals and could be partially replaced by the even less expensive halloysite nanoclay. Cellulose nanofibrils produced from renewable sources and naturally occurring halloysite nanoclay could be used as complementary reinforcing agents.

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Bots, Pieter, Joanna C. Renshaw, Timothy E. Payne, M. Josick Comarmond, Alexandra E. P. Schellenger, Matteo Pedrotti, Eleonora Calì, and Rebecca J. Lunn. "Geochemical evidence for the application of nanoparticulate colloidal silica gel for in situ containment of legacy nuclear wastes." Environmental Science: Nano 7, no. 5 (2020): 1481–95. http://dx.doi.org/10.1039/d0en00046a.

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Colloidal silica is a nanoparticulate material that could have a transformative effect on environmental risk management at nuclear legacy sites by preventing radioactive contamination through the in situ installation of injectable hydraulic barriers.

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Shen, Shukun, Peipei Sun, Lu Yang, Shaofei Song, Wei Li, and Daodao Hu. "Colloidal liquid aphrons directed growth of sol–gel silica exhibiting bimodal porosities." Microporous and Mesoporous Materials 214 (September 2015): 64–69. http://dx.doi.org/10.1016/j.micromeso.2015.04.012.

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49

KANEKO, HIDEO, and SADAO HIROTA. "Dielectric studies of emulsions of polyol in hydrophobic colloidal silica-oil gel." CHEMICAL & PHARMACEUTICAL BULLETIN 33, no. 12 (1985): 5167–77. http://dx.doi.org/10.1248/cpb.33.5167.

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Kim, M., and M. Y. Corapcioglu. "Modeling of gel barrier formation by using Colloidal Silica in saturated media." Environmental Technology 24, no. 4 (April 2003): 517–29. http://dx.doi.org/10.1080/09593330309385586.

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Journal articles on the topic 'Colloidal silica gel'

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