+ Translate
+ Most Popular
Gaucher's disease;thirty-two years experience at Siriraj Hospital
A study of Macrobathra Meyrick from China (Lepidoptera, Cosmopterigidae)
First occurrence in ores of tetragonal chalcocite
Effects of trace element nutrition on sleep patterns in adult women
N.Z. range management guidelines. 2. Design of grazing management systems for tussock country
A case of lipoma of the esophagus
A revision of world Acanthosomatidae (Heteroptera: Pentatomidae): keys to and descriptions of subfamilies, tribes and genera, with designation of types
Life history of the coronate scyphozoan Linuche unguiculata (Swartz, 1788)
Perceptual restoration of obliterated sounds
Mutagenicity studies on two chromium(III) coordination compounds
The formation of the skeleton. I. Growth of a long bone. 1st appearance of a center of calcification
Leucopenia and abnormal liver function in travellers on malaria chemoprophylaxis
The joint commission: four key root causes loom large in sentinel event data
Treatment of vitiligo with topical 15% lactic acid solution in combination with ultra violet-A
Behaviour of dairy cows within three hours after feed supply: I. Influence of housing type and time elapsing after feed supply
Observations of the propagation velocity and formation mechanism of burst fractures caused by gunshot
Management and control of patients with type 2 diabetes mellitus in Lebanon: results from the International Diabetes Management Practices Study (IDMPS)
The diet composition and nutritional knowledge of patients with anorexia nervosa
Physoporella croatica Herak, 1958 of the Slovak karst Anisian (Slovakia, the West Carpathians Mts.)
Bright lights, big noise. How effective are vehicle warning systems?
Ein Plesiosaurier-Rest mit Magensteinen aus mittlerem Lias von Quedlinburg
Incidence of Chlamydia trachomatis in patients with sterility
Monster soup: the microscope and Victorian fantasy
Preliminary tests with residual sprays against poultry lice
Duration of the life of plants in phylogeny

Mechanism of freezing of water in contact with mesoporous silicas MCM-41, SBA-15 and SBA-16: role of boundary water of pore outlets in freezing

Mechanism of freezing of water in contact with mesoporous silicas MCM-41, SBA-15 and SBA-16: role of boundary water of pore outlets in freezing

Physical Chemistry Chemical Physics: Pccp 13(38): 17222-17233

ISSN/ISBN: 1463-9076

PMID: 21879058

DOI: 10.1039/c1cp21458f

The freezing mechanism of water contacted with mesoporous silicas with uniform pore shapes, both cylindrical and cagelike, was studied by thermodynamic and structural analyses with differential scanning calorimetry (DSC) and X-ray diffraction (XRD) together with adsorption measurements. In the DSC data extra exothermic peaks were found at around 230 K for water confined in SBA-15, in addition to that due to the freezing of pore water. These peaks are most likely to be ascribed to the freezing of water present over the micropore and/or mesopore outlets of coronas in SBA-15. Freezing of water confined in SBA-16 was systematically analysed by DSC with changing the pore size. The freezing temperature was found to be around 232 K, close to the homogeneous nucleation temperature of bulk water, independent of the pore size when the pore diameter (d) < 7.0 nm. Water confined in the cagelike pores of SBA-16 is probably surrounded by a water layer (boundary water) at the outlets of channels to interconnect the pores and of fine corona-like pores, which is similar to that present at the outlet of cylindrical pores in MCM-41 and of cylindrical channels in SBA-15. The presence of the boundary water would be a key for water in SBA-16 to freeze at the homogeneous nucleation temperature. This phenomenon is similar to those well known for water droplets in oil and water droplets of clouds in the sky. The XRD data showed that the cubic ice I(c) was formed in SBA-16 as previously found in SBA-15 when d < 8.0 nm.

Please choose payment method:

(PDF emailed within 0-6 h: $19.90)

Accession: 054295679

Download citation: RISBibTeXText

Related references

An NMR study on the mechanisms of freezing and melting of water confined in spherically mesoporous silicas SBA-16. Physical Chemistry Chemical Physics: Pccp 18(27): 18555-18562, 2016

Simplified calculation of soil freezing depth with consideration of water migration to the freezing boundary. Water Resources 15(1): 9-17, 1988

Pulsed NMR studies of water in striated muscle non-freezing factor of water II. Spin-lattice relaxation times and the dynamics of the non-freezing fraction of water. Biochimica et Biophysica Acta - General Subjects 304(1): 56-64, 1973

Freezing behavior of water in small pores and the possible role in the freezing of plant tissues. Plant Physiology 76(1): 201-204, 1984

On an exact solution of heat transfer equation in freezing soil with constant freezing speed, accompanying uniform flow of suction water to the freezing front. Seppyo = Journal of the Japanese Society of Snow and Ice 37(1): 13-20, 1975

Role of Nanoscale Interfacial Proximity in Contact Freezing in Water. Journal of the American Chemical Society 143(5): 2272-2284, 2021

Investigation of non-freezing water in biological objects by using the NMR method. Non-freezing water of organs of winter cereals. Vodnyi rezhim rastenii v svyazi s raznymi ekologicheskimi usloviyami: 352-357, 1978

Aspects of the freezing process in a porous material-water system. Part 1. Freezing and the properties of water and ice. Cement and Concrete Research 29(4): 627-630, 1999

Structural characterization of water and ice in mesoporous SBA-15 silicas: II. The 'almost-filled' case for 86 Å pore diameter. Journal of Physics. Condensed Matter: An Institute of Physics Journal 20(20): 205107, 2008

Studies of water and ice in hydrophilic and hydrophobic mesoporous silicas: pore characterisation and phase transformations. Physical Chemistry Chemical Physics: Pccp 12(12): 2838-2849, 2010

Structural characterization of water and ice in mesoporous SBA-15 silicas IV: partially filled cases for 86 Å pore diameter. Journal of Physics. Condensed Matter: An Institute of Physics Journal 25(46): 465105, 2013

Evaluation of Effect of Predrying on the Porous Structure of Water-Swollen Coal Based on the Freezing Property of Pore Condensed Water. Energy and Fuels 13(5): 1058-1066, 1999

Freezing of a water droplet due to evaporation: heat transfer dominating the evaporation-freezing phenomena and the effect of boiling on freezing characteristics. International Journal of Refrigeration 25(2): 226-234, 2002

A study of freezing-melting hysteresis of water in different porous materials. Part II: surfactant-templated silicas. Physical Chemistry Chemical Physics: Pccp 13(36): 16358-16365, 2011

A molecular simulation study on adsorption of acetone/water in mesoporous silicas modified by pore surface silylation. Journal of Chemical Engineering of Japan 38(12): 999-1007, 2005