scholarly journals Changes in Membrane Permeability of Winter Wheat Cells following Freeze-Thaw Injury as Determined by Nuclear Magnetic Resonance

1978 ◽  
Vol 61 (6) ◽  
pp. 878-882 ◽  
Author(s):  
Paul M. Chen ◽  
Lawrence V. Gusta ◽  
Daryl G. Stout
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Winter Wheat ◽  
Membrane Permeability ◽  
Freeze Thaw ◽  
Nuclear Magnetic

scholarly journals Microscopic Characteristic Analysis on Sandstone under Coupling Effect of Freeze–Thaw and Acidic Treatment: From Nuclear Magnetic Resonance Perspective

2020 ◽  
Vol 10 (16) ◽  
pp. 5699
Author(s):  
Songtao Yu ◽  
Hongwei Deng ◽  
Guanglin Tian ◽  
Junren Deng
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Acid Solution ◽  
Coupling Effect ◽  
Fractal Dimensions ◽  
Total Porosity ◽  
Characteristic Analysis ◽  
Freeze Thaw ◽  
Ph Decrease ◽  
Nuclear Magnetic

Microscopic characteristics greatly affect mechanical and physical properties as they exert vital impact on the stability and durability of materials. In this paper, widely distributed sandstone was chosen as the research object. Sandstone was treated with a coupled effect of Freeze–Thaw (F–T) weathering and acid solution, where freeze–thaw cycles were set as 0, 10, 20, 30 and 40 cycles, and the pH of the acid solution were set as 2.8, 4.2, 5.6 and 7.0, respectively. Then, nuclear magnetic resonance was applied to measure the microscopic characteristics of sandstone, then porosity, pore size distribution and permeability before the fractal dimensions were obtained and calculated. Results show that porosity increases when F–T cycles increase, and its increase grows with the pH of acid solution decrease during the first 10 F–T cycles. Macro porosity, meso porosity and micro porosity account for the largest, second largest and smallest ratio of porosity growth. Meso porosity, micro porosity and macro porosity account for the largest, second largest and smallest ratio of total porosity. Permeability increases obviously with F–T cycle increase, while acid erosion exerts little influence on permeability increment overall. Fractal dimensions of meso pores and macro pores increase with F–T cycle increase overall, and they increase with pH decrease overall. Porosity has strong exponentially correlation with permeability. Fractal dimensions of meso pores and macro pores have good linearly correlation with permeability, while correlation between porosity and fractal dimensions are not that obvious.

Nuclear Magnetic Resonance Analysis of Air Entraining Natural Pumice Concrete Freeze-Thaw Damage

2014 ◽  
Vol 919-921 ◽  
pp. 1939-1943 ◽  
Author(s):  
Xiao Xiao Wang ◽  
Xiang Dong Shen ◽  
Hai Long Wang ◽  
Hong Xia Zhao
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Saline Solution ◽  
Nuclear Magnetic Resonance Analysis ◽  
Spectral Parameters ◽  
Freeze Thaw ◽  
Resonance Analysis ◽  
Concrete Damage ◽  
Intuitive Method ◽  
Nuclear Magnetic

Based on the existed research and analysis methods of air entraining natural pumice concrete freeze-thaw damage, nuclear magnetic resonance (NMR) detection technique was introduced in the present study. From the research of essence of freeze-thaw coupling-induced concrete damage in saline solution, natural pumice concrete porosity and transversal relaxation time T2 spectral parameters were used as criteria, and nuclear magnetic resonance imaging (NMRI) technology, an intuitive method was used to determine freeze-thaw damage quantitatively.

Formation of unilamellar vesicles by repetitive freeze-thaw cycles: characterization by electron microscopy and 31 P-nuclear magnetic resonance

2000 ◽  
Vol 29 (3) ◽  
pp. 184-195 ◽  
Author(s):  
Mounir Traïkia ◽  
Dror E. Warschawski ◽  
Michel Recouvreur ◽  
Jean Cartaud ◽  
Philippe F. Devaux
Keyword(s):  
Electron Microscopy ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Unilamellar Vesicles ◽  
Freeze Thaw ◽  
Nuclear Magnetic

scholarly journals Freezing-Thawing Damage Mechanism of Coal Gangue Concrete Based on Low-Field Nuclear Magnetic Resonance, Scanning Electron Microscopy, and N2 Adsorption

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Bowen Hou ◽  
Jisheng Qiu ◽  
Peng Guo ◽  
Xujun Gao ◽  
Ruyi Zhang
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Failure Mechanism ◽  
Coal Gangue ◽  
N2 Adsorption ◽  
Freeze Thaw ◽  
Low Field ◽  
Structural Deterioration ◽  
Thaw Cycle ◽  
Nuclear Magnetic

To study waterborne frost heaving failure mechanism of coal gangue ceramsite concrete (CGCC) under freeze-thaw cycles, capillary water absorption test, nonmetallic ultrasonic testing test, low-field nuclear magnetic resonance (LNMR) test, N2 adsorption test, and other tests were used to determine the effect of freeze-thaw cycles on the porosity, relative dynamic elastic modulus (RDM), and capillary adsorption rate of different coal gangue ceramsite (MT) replacement rates (0, 20%, 40%, and 60%). Combining the changes of performance indexes and the changes of micropore structure under freeze-thaw cycles, the freeze-thaw failure mechanism of normal concrete (OC) and CGCC was analyzed. In view of the particularity of MT material, the method based on pore size is put forward to distinguish M pores from T pores, and the reasons for different properties are analyzed from the microperspective. The results show that the freeze-thaw cycle changes the microstructure of coal gangue concrete and has an obvious influence on its properties. And when the replacement rate is 40%, degradation mitigation performance is optimal. Due to the particularity of MT shape, T pores are dominant in coal gangue concrete matrix, which is different from the microstructure of ordinary concrete and can reduce the structural deterioration caused by freeze-thaw. The research results of this paper can provide a reference for the research and application of CGCC in freeze-thaw environment.

scholarly journals Nuclear magnetic resonance analysis of freeze-thaw damage in natural pumice concrete

2016 ◽  
Vol 66 (322) ◽  
pp. e087 ◽  
Author(s):  
Xiangdong Shen ◽  
Xiaoxiao Wang ◽  
Hailong Wang ◽  
Chu Gao ◽  
Tong Zhang
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Nuclear Magnetic Resonance Analysis ◽  
Freeze Thaw ◽  
Resonance Analysis ◽  
Nuclear Magnetic
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