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Encapsulation of Magnesium with Lentil Flour by Using Double Emulsion to Produce Magnesium Enriched Cakes. FOOD BIOPROCESS TECH 2021. [DOI: 10.1007/s11947-021-02672-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Lin T, Li S, Gao X, Zhang Y. Improved technology using transmitting currents with short shutdown times for surface nuclear magnetic resonance. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:084501. [PMID: 32872898 DOI: 10.1063/5.0007848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 08/09/2020] [Indexed: 06/11/2023]
Abstract
Surface nuclear magnetic resonance (SNMR) technology is widely used in the detection of groundwater. However, the dead time arising from the coupling effect of the transmitting circuit on the receiving coil results in partial or complete loss of the SNMR signal. This situation is especially unfavorable for the detection of short relaxation time targets. To solve this problem, we analyzed the shortcomings of the traditional SNMR launch system, and we propose a new transmission method based on an untuned constant voltage-clamped technology to overcome the problems of high resonance voltage, an uncontrollable shutdown process, and long shutdown times. Untuned transmission topology without a matching capacitor, pulse width modulation, and a constant voltage-clamped technique were applied to guide the current rise and shutdown of the system in a controllable way using an integer-period transmission pulse. A simulation experiment comparing the traditional method of transmission and this new method was conducted. The results showed that not only can the new method control the transmission current shutdown process but it can also avoid the delay in response. When the transmitting current drops from 10 A to 0.12 µA, the traditional method requires 2.29 ms and the new method requires only 4 µs. The new transmission system that we have developed based on an untuned constant voltage-clamped technology can improve the level of the transmitting current effectively and shorten the shutdown time.
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Affiliation(s)
- Tingting Lin
- Key Laboratory for Geophysical Instrument of Ministry of Education, Changchun 130061, China and College of Instrumentation & Electrical Engineering, Jilin University, Changchun 130061, China
| | - Suhang Li
- Key Laboratory for Geophysical Instrument of Ministry of Education, Changchun 130061, China and College of Instrumentation & Electrical Engineering, Jilin University, Changchun 130061, China
| | - Xing Gao
- Key Laboratory for Geophysical Instrument of Ministry of Education, Changchun 130061, China and College of Instrumentation & Electrical Engineering, Jilin University, Changchun 130061, China
| | - Yang Zhang
- Key Laboratory for Geophysical Instrument of Ministry of Education, Changchun 130061, China and College of Instrumentation & Electrical Engineering, Jilin University, Changchun 130061, China
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Wang J, Xiao L, Liao G, Zhang Y, Cui Y, Sun Z, Dong Y, Hu L. NMR characterizing mixed wettability under intermediate-wet condition. Magn Reson Imaging 2019; 56:156-160. [DOI: 10.1016/j.mri.2018.09.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Revised: 09/21/2018] [Accepted: 09/22/2018] [Indexed: 10/28/2022]
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Vashaee S, Li M, Newling B, MacMillan B, Marica F, Kwak HT, Gao J, Al-Harbi AM, Balcom BJ. Local T 1-T 2 distribution measurements in porous media. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2018; 287:113-122. [PMID: 29335164 DOI: 10.1016/j.jmr.2018.01.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 12/18/2017] [Accepted: 01/03/2018] [Indexed: 06/07/2023]
Abstract
A novel slice-selective T1-T2 measurement is proposed to measure spatially resolved T1-T2 distributions. An adiabatic inversion pulse is employed for slice-selection. The slice-selective pulse is able to select a quasi-rectangular slice, on the order of 1 mm, at an arbitrary position within the sample.The method does not employ conventional selective excitation in which selective excitation is often accomplished by rotation of the longitudinal magnetization in the slice of interest into the transverse plane, but rather a subtraction based on CPMG data acquired with and without adiabatic inversion slice selection. T1 weighting is introduced during recovery from the inversion associated with slice selection. The local T1-T2 distributions measured are of similar quality to bulk T1-T2 measurements. The new method can be employed to characterize oil-water mixtures and other fluids in porous media. The method is beneficial when a coarse spatial distribution of the components is of interest.
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Affiliation(s)
- S Vashaee
- UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
| | - M Li
- UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
| | - B Newling
- UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
| | - B MacMillan
- UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
| | - F Marica
- UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
| | - H T Kwak
- Saudi Aramco EXPEC Advanced Research Center, Reservoir Engineering Technology Division, Pore Scale Physics Focus Area, Bldg. 2291, #GA-168, Saudi Arabia.
| | - J Gao
- Saudi Aramco EXPEC Advanced Research Center, Reservoir Engineering Technology Division, Pore Scale Physics Focus Area, Bldg. 2291, #GA-168, Saudi Arabia.
| | - A M Al-Harbi
- Saudi Aramco EXPEC Advanced Research Center, Reservoir Engineering Technology Division, Pore Scale Physics Focus Area, Bldg. 2291, #GA-168, Saudi Arabia.
| | - B J Balcom
- UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
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Vashaee S, Newling B, MacMillan B, Marica F, Li M, Balcom BJ. Local diffusion and diffusion-T 2 distribution measurements in porous media. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 278:104-112. [PMID: 28388495 DOI: 10.1016/j.jmr.2017.03.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 03/21/2017] [Accepted: 03/22/2017] [Indexed: 06/07/2023]
Abstract
Slice-selective pulsed field gradient (PFG) and PFG-T2 measurements are developed to measure spatially-resolved molecular diffusion and diffusion-T2 distributions. A spatially selective adiabatic inversion pulse was employed for slice-selection. The slice-selective pulse is able to select a coarse slice, on the order of 1cm, at an arbitrary position in the sample. The new method can be employed to characterize oil-water mixtures in porous media. The new technique has an inherent sensitivity advantage over phase encoding imaging based methods due to signal being localized from a thick slice. The method will be advantageous for magnetic resonance of porous media at low field where sensitivity is problematic. Experimental CPMG data, following PFG diffusion measurement, were compromised by a transient ΔB0(t) field offset. The off resonance effects of ΔB0(t) were examined by simulation. The ΔB0 offset artifact in D-T2 distribution measurements may be avoided by employing real data, instead of magnitude data.
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Affiliation(s)
- S Vashaee
- UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
| | - B Newling
- UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
| | - B MacMillan
- UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
| | - F Marica
- UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
| | - M Li
- UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
| | - B J Balcom
- UNB MRI Centre, Department of Physics, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada.
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Zhang Y, Xiao L, Liao G, Song YQ. Direct correlation of diffusion and pore size distributions with low field NMR. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 269:196-202. [PMID: 27371788 DOI: 10.1016/j.jmr.2016.06.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 06/17/2016] [Accepted: 06/17/2016] [Indexed: 06/06/2023]
Abstract
The time-dependent diffusion coefficient (D) is a powerful tool to probe microstructure in porous media, and can be obtained by the NMR method. In a real porous sample, molecular diffusion is very complex. Here we present a new method which directly measures the relationship between effective diffusion coefficients and pore size distributions without knowing surface relaxivity. This method is used to extract structural information and explore the relationship between D and a in porous media having broad pore size distributions. The diffusion information is encoded by the Pulsed Field Gradient (PFG) method and the pore size distributions are acquired by the Decay due to Diffusion in the Internal Field (DDIF) method. Two model samples were measured to verify this method. Restricted diffusion was analyzed, and shows that most fluid molecules experience pore wall. The D(a) curves obtained from correlation maps were fitted to the Padé approximant equation and a good agreement was found between the fitting lines and the measured data. Then a sandstone sample with unknown structure was measured. The state of confined fluids was analyzed and structural information, such as pore size distributions, were extracted. The D - T1 correlation maps were also obtained using the same method, which yielded surface relaxivities for different samples. All the experiments were conducted on 2MHz NMR equipment to obtain accurate diffusion information, where internal gradients can be neglected. This method is expected to have useful applications in the oil industry, particularly for NMR logging in the future.
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Affiliation(s)
- Yan Zhang
- State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China
| | - Lizhi Xiao
- State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China.
| | - Guangzhi Liao
- State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China
| | - Yi-Qiao Song
- Schlumberger-Doll Research, One Hampshire Street, Cambridge, MA 02139, United States
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Zhang Y, Xiao L, Liao G, Blümich B. Direct correlation of internal gradients and pore size distributions with low field NMR. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 267:37-42. [PMID: 27111138 DOI: 10.1016/j.jmr.2016.04.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 04/13/2016] [Accepted: 04/18/2016] [Indexed: 06/05/2023]
Abstract
Internal magnetic field gradients Gint, which arise from the magnetic susceptibility difference Δχ between solid matrix and fluid in porous media relate to the pore geometry. However, this relationship is complex and not well understood. Here we correlate internal-gradient distributions to pore-size distributions directly to examine internal gradients in detail at low field NMR. The pore-size distributions were obtained by the method of Decay due to Diffusion in the Internal Field (DDIF), and the internal-gradient distributions were measured with the Carr-Purcell-Meiboom-Gill (CPMG) method. The internal-gradient-pore-size distributions correlation maps were obtained for water in packs of glass beads with different diameter and in a sandstone sample. The relationship between internal gradients and pore structure is analyzed in detail by considering the restricted diffusion of fluids in porous samples. For each case diffusion regimes are assigned by plotting normalized CPMG data and comparing the diffusion lengths, the dephasing lengths and pore diameters. In the free-diffusion limit, the correlation maps reveal the true relationship between pore structure and internal gradients so that Δχ can be approximated from the correlation maps. This limit is met most easily at low field. It provides information about porous media, which is expected to benefit the oil industry, in particular NMR well logging.
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Affiliation(s)
- Yan Zhang
- State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China
| | - Lizhi Xiao
- State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China.
| | - Guangzhi Liao
- State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China
| | - Bernhard Blümich
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Germany
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