Abstract

Raman spectroscopy has been used to provide a rapid, noninvasive, and nondestructive quantification method for determining the parahydrogen fraction of hydrogen gas. The basis of the method is the measurement of the ratio of the first two rotational bands of hydrogen at 355 cm−1 and 586 cm−1 corresponding to parahydrogen and orthohydrogen, respectively. The method has been used to determine the parahydrogen content during a production process and a reaction. In the first example, the performance of an in-house liquid nitrogen cooled parahydrogen generator was monitored both at-line and on-line. The Raman measurements showed that it took several hours for the generator to reach steady state and, hence, for maximum parahydrogen production (50%) to be reached. The results obtained using Raman spectroscopy were compared to those obtained by at-line low-field nuclear magnetic resonance (NMR) spectroscopy. While the results were in good agreement, Raman analysis has several advantages over NMR for this application. The Raman method does not require a reference sample, as both spin isomers (ortho and para) of hydrogen can be directly detected, which simplifies the procedure and eliminates some sources of error. In the second example, the method was used to monitor the fast conversion of parahydrogen to orthohydrogen in situ. Here the ability to acquire Raman spectra every 30 s enabled a conversion process with a rate constant of 27.4×10-4 s−1 to be monitored. The Raman method described here represents an improvement on previously reported work, in that it can be easily applied on-line and is approximately 500 times faster. This offers the potential of an industrially compatible method for determining parahydrogen content in applications that require the storage and usage of hydrogen.

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2018 (2)

P.M. Richardson, S. Jackson, A.J. Parrott, A. Nordon et al. “A Simple Hand-Held Magnet Array for Efficient and Reproducible SABRE Hyperpolarisation Using Manual Sample Shaking”. Magn. Reson. Chem. 2018. 56: 641–650.

P.M. Richardson, A.J. Parrott, O. Semenova, A. Nordon et al. “SABRE Hyperpolarization Enables High-Sensitivity 1H and 13C Benchtop NMR Spectroscopy”. Analyst. 2018. 143: 3442–3450.

2017 (2)

D.V. Petrov, I.I. Matrosov “Pressure Dependence of the Raman Signal Intensity in High-Pressure Gases”. J. Raman. Spectrosc. 2017. 48: 474–478.

I. Reile, R.L.E.G. Aspers, J.M. Tyburn, J.G. Kempf et al. “DOSY Analysis of Micromolar Analytes: Resolving Dilute Mixtures by SABRE Hyperpolarization”. Angew. Chem. Int. Ed. 2017. 56: 9174–9177.

2016 (5)

D.V. Petrov, I.I. Matrosov “Raman Gas Analyzer (RGA): Natural Gas Measurements”. Appl. Spectrosc. 2016. 70(10): 1770–1776.

K. Sundararajan, K. Sankaran, N. Ramanathan, R. Gopi “Production and Characterization of Para-Hydrogen Gas for Matrix Isolation Infrared Spectroscopy”. J. Mol. Struct. 2016. 1117: 181–191.

L.M. Sutherland, J.N. Knudson, M. Mocko, R.M. Renneke “Practical In-Situ Determination of Ortho-Para Hydrogen Ratios Via Fiber-Optic Based Raman Spectroscopy”. Nucl. Instrum. Methods Phys. Res., Sect. A. 2016. 810: 182–185.

M. Teshigawara, M. Harada, H. Tatsumoto, T. Aso et al. “Experimental Verification of Equilibrium Para-Hydrogen Levels in Hydrogen Moderators Irradiated by Spallation Neutrons at J-PARC”. Nucl. Instrum. Methods Phys. Res., Sect. B. 2016. 368: 66–70.

M.E. Halse “Perspectives for Hyperpolarisation in Compact NMR”. TrAC, Trends Anal. Chem. 2016. 83: 76–83.

2015 (1)

J. Kiefer “Recent Advances in the Characterization of Gaseous and Liquid Fuels by Vibrational Spectroscopy”. Energies. 2015. 8: 3165–3197.

2014 (2)

R.E. Mewis, K.D. Atkinson, M.J. Cowley, S.B. Duckett et al. “Probing Signal Amplification by Reversible Exchange Using an NMR Flow System”. Magn. Reson. Chem. 2014. 52(February): 358–369.

G. Petitpas, S.M. Aceves, M.J. Matthews, J.R. Smith “Para-H2 to Ortho-H2 Conversion in a Full-Scale Automotive Cryogenic Pressurized Hydrogen Storage up to 345 Bar”. Int. J. Hydrogen. Energy. 2014. 39(12): 6533–6547.

2013 (1)

J.B. Hövener, S. Bär, J. Leupold, K. Jenne et al. “A Continuous-Flow, High-Throughput, High-Pressure Parahydrogen Converter for Hyperpolarization in a Clinical Setting”. NMR Biomed. 2013. 26(2): 124–131.

2012 (4)

B. Feng, A.M. Coffey, R.D. Colon, E.Y. Chekmenev et al. “A Pulsed Injection Parahydrogen Generator and Techniques for Quantifying Enrichment”. J. Magn. Reson. 2012. 214: 258–262.

S.B. Duckett, R.E. Mewis “Application of Parahydrogen Induced Polarization Techniques in NMR Spectroscopy and Imaging”. Acc. Chem. Res. 2012. 45(8): 1247–1257.

R.A. Green, R.W. Adams, S.B. Duckett, R.W. Mewis et al. “The Theory and Practice of Hyperpolarization in Magnetic Resonance Using Parahydrogen”. Prog. Nucl. Magn. Reson. Spectrosc. 2012. 67: 1–48.

L.S. Lloyd, R.W. Adams, M. Bernstein, S. Coombes et al. “Utilization of SABRE Derived Hyperpolarization to Detect Low Concentration Analytes via 1D- and 2D-NMR Methods”. J. Am. Chem. Soc. 2012. 134: 12904–12907.

2011 (1)

M.J. Matthews, G. Petitpas, and S.M. Aceves “A Study of Spin Isomer Conversion Kinetics in Supercritical Fluid Hydrogen for Cryogenic Fuel Storage Technologies”. Appl. Phys. Lett. 2011. 99(8): 1–4.

2010 (3)

A. Gamliel, H. Allouche-Arnon, R. Nalbandian, C.M. Barzilay et al. “An Apparatus for Production of Isotopically and Spin-Enriched Hydrogen for Induced Polarization Studies”. Appl. Magn. Reson. 2010. 39(4): 329–345.

S.C. Eichmann, M. Weschta, J. Kiefer, T. Seeger et al. “Characterization of a Fast Gas Analyzer Based on Raman Scattering for the Analysis of Synthesis Gas”. Rev. Sci. Instrum. 2010. 81(12): 125104.

N. Sakoda, K. Shindo, K. Shinzato, M. Kohno et al. “Review of the Thermodynamic Properties of Hydrogen Based on Existing Equations of State”. Int. J. Thermophys. 2010. 31(2): 276–296.

2009 (2)

J.W. Leachman, R.T. Jacobsen, S.G. Penoncello, E.W. Lemmon “Fundamental Equations of State for Parahydrogen, Normal Hydrogen, and Orthohydrogen”. J. Phys. Chem. Ref. Data. 2009. 38(3): 721–748.

B.A. Tom, S. Bhasker, Y. Miyamoto, T. Momose et al. “Producing and Quantifying Enriched Para-H2”. Rev. Sci. Instrum. 2009. 80(1): 016108.

2008 (1)

S.B. Duckett, N.J. Wood “Parahydrogen-Based NMR Methods as a Mechanistic Probe in Inorganic Chemistry”. Coord. Chem. Rev. 2008. 252(21–22): 2278–2291.

2006 (1)

G. Buntkowsky, B. Walaszek, A. Adamczyk, Y. Xu et al. Mechanism of Nuclear Spin Initiated Para-H2 to Ortho-H2 Conversion”. Phys. Chem. Chem. Phys. 2006. 8(16): 1929–1935.

2005 (1)

M. Matsumoto, J.H. Espenson “Kinetics of the Interconversion of Parahydrogen and Orthohydrogen Catalyzed by Paramagnetic Complex Ions”. J. Am. Chem. Soc. 2005. 127(32): 11447–11453.

2004 (1)

D. Blazina, S.B. Duckett, J.P. Dunne, C. Godard “Applications of the Parahydrogen Phenomenon in Inorganic Chemistry”. Dalton Trans. 2004. 17, 2601–2609.

1999 (2)

S.B. Duckett, C.J. Sleigh “Applications of the Parahydrogen Phenomenon: A Chemical Perspective”. Prog. Nucl. Magn. Reson. Spectrosc. 1999. 34(1): 71–92.

S. Tam, M.E. Fajardo “Ortho/Para Hydrogen Converter for Rapid Deposition Matrix Isolation Spectroscopy”. Rev. Sci. Instrum. 1999. 70(4): 1926–1932.

1997 (1)

J. Natterer, J. Bargon “Parahydrogen Induced Polarization”. Prog. Nucl. Magn. Reson. Spectrosc. 1997. 31: 293–315.

1992 (1)

E. Ilisca “Ortho-Para Conversion of Hydrogen Molecules Physisorbed on Surfaces”. Prog. Surf. Sci. 1992. 41: 217–335.

1991 (1)

R. Eisenberg “Parahydrogen-Induced Polarization: A New Spin on Reactions with H2”. Acc. Chem. Res. 1991. 24(4): 110–116.

1987 (2)

T.C. Eisenschmid, R.U. Kirss, P.P. Deutsch, S.I. Hommeltoft et al. “Para Hydrogen Induced Polarization in Hydrogenation Reactions”. J. Am. Chem. Soc. 1987. 109(26): 8089–8091.

T.W. Bradshaw, J.O.W. Norris “Observations on the Use of a Thermal Conductivity Cell to Measure the Para Hydrogen Concentration in a Mixture of Para and Ortho Hydrogen Gas”. Rev. Sci. Instrum. 1987. 58(1): 83–85.

1984 (1)

J.L. Hunt, J.D. Poll, and L. Wolniewicz “Ab Initio Calculation of Properties of the Neutral Diatomic Hydrogen Molecules H2, HD, D2, HT, DT and T2. Can. J. Phys. 1984. 62: 1719–1723.

1975 (1)

P.A. Fleury, J.P. McTague “Molecular Interactions in the Condensed Phases of Ortho-Para Hydrogen Mixtures”. Phys. Rev. 1975. 12(1): 317–326.

Aceves, S.M.

G. Petitpas, S.M. Aceves, M.J. Matthews, J.R. Smith “Para-H2 to Ortho-H2 Conversion in a Full-Scale Automotive Cryogenic Pressurized Hydrogen Storage up to 345 Bar”. Int. J. Hydrogen. Energy. 2014. 39(12): 6533–6547.

M.J. Matthews, G. Petitpas, and S.M. Aceves “A Study of Spin Isomer Conversion Kinetics in Supercritical Fluid Hydrogen for Cryogenic Fuel Storage Technologies”. Appl. Phys. Lett. 2011. 99(8): 1–4.

Adamczyk, A.

G. Buntkowsky, B. Walaszek, A. Adamczyk, Y. Xu et al. Mechanism of Nuclear Spin Initiated Para-H2 to Ortho-H2 Conversion”. Phys. Chem. Chem. Phys. 2006. 8(16): 1929–1935.

Adams, R.W.

R.A. Green, R.W. Adams, S.B. Duckett, R.W. Mewis et al. “The Theory and Practice of Hyperpolarization in Magnetic Resonance Using Parahydrogen”. Prog. Nucl. Magn. Reson. Spectrosc. 2012. 67: 1–48.

L.S. Lloyd, R.W. Adams, M. Bernstein, S. Coombes et al. “Utilization of SABRE Derived Hyperpolarization to Detect Low Concentration Analytes via 1D- and 2D-NMR Methods”. J. Am. Chem. Soc. 2012. 134: 12904–12907.

Allouche-Arnon, H.

A. Gamliel, H. Allouche-Arnon, R. Nalbandian, C.M. Barzilay et al. “An Apparatus for Production of Isotopically and Spin-Enriched Hydrogen for Induced Polarization Studies”. Appl. Magn. Reson. 2010. 39(4): 329–345.

Aso, T.

M. Teshigawara, M. Harada, H. Tatsumoto, T. Aso et al. “Experimental Verification of Equilibrium Para-Hydrogen Levels in Hydrogen Moderators Irradiated by Spallation Neutrons at J-PARC”. Nucl. Instrum. Methods Phys. Res., Sect. B. 2016. 368: 66–70.

Aspers, R.L.E.G.

I. Reile, R.L.E.G. Aspers, J.M. Tyburn, J.G. Kempf et al. “DOSY Analysis of Micromolar Analytes: Resolving Dilute Mixtures by SABRE Hyperpolarization”. Angew. Chem. Int. Ed. 2017. 56: 9174–9177.

Atkins, P.W.

P.W. Atkins, J. de Paula. Atkins’ Physical Chemistry, Oxford, UK: Oxford University Press, 2010. 9th ed.

Atkinson, K.D.

R.E. Mewis, K.D. Atkinson, M.J. Cowley, S.B. Duckett et al. “Probing Signal Amplification by Reversible Exchange Using an NMR Flow System”. Magn. Reson. Chem. 2014. 52(February): 358–369.

Bär, S.

J.B. Hövener, S. Bär, J. Leupold, K. Jenne et al. “A Continuous-Flow, High-Throughput, High-Pressure Parahydrogen Converter for Hyperpolarization in a Clinical Setting”. NMR Biomed. 2013. 26(2): 124–131.

Bargon, J.

J. Natterer, J. Bargon “Parahydrogen Induced Polarization”. Prog. Nucl. Magn. Reson. Spectrosc. 1997. 31: 293–315.

Barzilay, C.M.

A. Gamliel, H. Allouche-Arnon, R. Nalbandian, C.M. Barzilay et al. “An Apparatus for Production of Isotopically and Spin-Enriched Hydrogen for Induced Polarization Studies”. Appl. Magn. Reson. 2010. 39(4): 329–345.

Bernstein, M.

L.S. Lloyd, R.W. Adams, M. Bernstein, S. Coombes et al. “Utilization of SABRE Derived Hyperpolarization to Detect Low Concentration Analytes via 1D- and 2D-NMR Methods”. J. Am. Chem. Soc. 2012. 134: 12904–12907.

Bhasker, S.

B.A. Tom, S. Bhasker, Y. Miyamoto, T. Momose et al. “Producing and Quantifying Enriched Para-H2”. Rev. Sci. Instrum. 2009. 80(1): 016108.

Blazina, D.

D. Blazina, S.B. Duckett, J.P. Dunne, C. Godard “Applications of the Parahydrogen Phenomenon in Inorganic Chemistry”. Dalton Trans. 2004. 17, 2601–2609.

Bradshaw, T.W.

T.W. Bradshaw, J.O.W. Norris “Observations on the Use of a Thermal Conductivity Cell to Measure the Para Hydrogen Concentration in a Mixture of Para and Ortho Hydrogen Gas”. Rev. Sci. Instrum. 1987. 58(1): 83–85.

Buntkowsky, G.

G. Buntkowsky, B. Walaszek, A. Adamczyk, Y. Xu et al. Mechanism of Nuclear Spin Initiated Para-H2 to Ortho-H2 Conversion”. Phys. Chem. Chem. Phys. 2006. 8(16): 1929–1935.

Chekmenev, E.Y.

B. Feng, A.M. Coffey, R.D. Colon, E.Y. Chekmenev et al. “A Pulsed Injection Parahydrogen Generator and Techniques for Quantifying Enrichment”. J. Magn. Reson. 2012. 214: 258–262.

Coffey, A.M.

B. Feng, A.M. Coffey, R.D. Colon, E.Y. Chekmenev et al. “A Pulsed Injection Parahydrogen Generator and Techniques for Quantifying Enrichment”. J. Magn. Reson. 2012. 214: 258–262.

Colon, R.D.

B. Feng, A.M. Coffey, R.D. Colon, E.Y. Chekmenev et al. “A Pulsed Injection Parahydrogen Generator and Techniques for Quantifying Enrichment”. J. Magn. Reson. 2012. 214: 258–262.

Coombes, S.

L.S. Lloyd, R.W. Adams, M. Bernstein, S. Coombes et al. “Utilization of SABRE Derived Hyperpolarization to Detect Low Concentration Analytes via 1D- and 2D-NMR Methods”. J. Am. Chem. Soc. 2012. 134: 12904–12907.

Cowley, M.J.

R.E. Mewis, K.D. Atkinson, M.J. Cowley, S.B. Duckett et al. “Probing Signal Amplification by Reversible Exchange Using an NMR Flow System”. Magn. Reson. Chem. 2014. 52(February): 358–369.

de Paula, J.

P.W. Atkins, J. de Paula. Atkins’ Physical Chemistry, Oxford, UK: Oxford University Press, 2010. 9th ed.

Deutsch, P.P.

T.C. Eisenschmid, R.U. Kirss, P.P. Deutsch, S.I. Hommeltoft et al. “Para Hydrogen Induced Polarization in Hydrogenation Reactions”. J. Am. Chem. Soc. 1987. 109(26): 8089–8091.

Duckett, S.B.

R.E. Mewis, K.D. Atkinson, M.J. Cowley, S.B. Duckett et al. “Probing Signal Amplification by Reversible Exchange Using an NMR Flow System”. Magn. Reson. Chem. 2014. 52(February): 358–369.

R.A. Green, R.W. Adams, S.B. Duckett, R.W. Mewis et al. “The Theory and Practice of Hyperpolarization in Magnetic Resonance Using Parahydrogen”. Prog. Nucl. Magn. Reson. Spectrosc. 2012. 67: 1–48.

S.B. Duckett, R.E. Mewis “Application of Parahydrogen Induced Polarization Techniques in NMR Spectroscopy and Imaging”. Acc. Chem. Res. 2012. 45(8): 1247–1257.

S.B. Duckett, N.J. Wood “Parahydrogen-Based NMR Methods as a Mechanistic Probe in Inorganic Chemistry”. Coord. Chem. Rev. 2008. 252(21–22): 2278–2291.

D. Blazina, S.B. Duckett, J.P. Dunne, C. Godard “Applications of the Parahydrogen Phenomenon in Inorganic Chemistry”. Dalton Trans. 2004. 17, 2601–2609.

S.B. Duckett, C.J. Sleigh “Applications of the Parahydrogen Phenomenon: A Chemical Perspective”. Prog. Nucl. Magn. Reson. Spectrosc. 1999. 34(1): 71–92.

Dunne, J.P.

D. Blazina, S.B. Duckett, J.P. Dunne, C. Godard “Applications of the Parahydrogen Phenomenon in Inorganic Chemistry”. Dalton Trans. 2004. 17, 2601–2609.

Eichmann, S.C.

S.C. Eichmann, M. Weschta, J. Kiefer, T. Seeger et al. “Characterization of a Fast Gas Analyzer Based on Raman Scattering for the Analysis of Synthesis Gas”. Rev. Sci. Instrum. 2010. 81(12): 125104.

Eisenberg, R.

R. Eisenberg “Parahydrogen-Induced Polarization: A New Spin on Reactions with H2”. Acc. Chem. Res. 1991. 24(4): 110–116.

Eisenschmid, T.C.

T.C. Eisenschmid, R.U. Kirss, P.P. Deutsch, S.I. Hommeltoft et al. “Para Hydrogen Induced Polarization in Hydrogenation Reactions”. J. Am. Chem. Soc. 1987. 109(26): 8089–8091.

Espenson, J.H.

M. Matsumoto, J.H. Espenson “Kinetics of the Interconversion of Parahydrogen and Orthohydrogen Catalyzed by Paramagnetic Complex Ions”. J. Am. Chem. Soc. 2005. 127(32): 11447–11453.

Fajardo, M.E.

S. Tam, M.E. Fajardo “Ortho/Para Hydrogen Converter for Rapid Deposition Matrix Isolation Spectroscopy”. Rev. Sci. Instrum. 1999. 70(4): 1926–1932.

Farkas, A.

A. Farkas. Orthohydrogen, Parahydrogen and Heavy Hydrogen, London: Cambridge University Press, 1935.

Feng, B.

B. Feng, A.M. Coffey, R.D. Colon, E.Y. Chekmenev et al. “A Pulsed Injection Parahydrogen Generator and Techniques for Quantifying Enrichment”. J. Magn. Reson. 2012. 214: 258–262.

Fleury, P.A.

P.A. Fleury, J.P. McTague “Molecular Interactions in the Condensed Phases of Ortho-Para Hydrogen Mixtures”. Phys. Rev. 1975. 12(1): 317–326.

Gamliel, A.

A. Gamliel, H. Allouche-Arnon, R. Nalbandian, C.M. Barzilay et al. “An Apparatus for Production of Isotopically and Spin-Enriched Hydrogen for Induced Polarization Studies”. Appl. Magn. Reson. 2010. 39(4): 329–345.

Godard, C.

D. Blazina, S.B. Duckett, J.P. Dunne, C. Godard “Applications of the Parahydrogen Phenomenon in Inorganic Chemistry”. Dalton Trans. 2004. 17, 2601–2609.

Gopi, R.

K. Sundararajan, K. Sankaran, N. Ramanathan, R. Gopi “Production and Characterization of Para-Hydrogen Gas for Matrix Isolation Infrared Spectroscopy”. J. Mol. Struct. 2016. 1117: 181–191.

Green, R.A.

R.A. Green, R.W. Adams, S.B. Duckett, R.W. Mewis et al. “The Theory and Practice of Hyperpolarization in Magnetic Resonance Using Parahydrogen”. Prog. Nucl. Magn. Reson. Spectrosc. 2012. 67: 1–48.

Halse, M.E.

M.E. Halse “Perspectives for Hyperpolarisation in Compact NMR”. TrAC, Trends Anal. Chem. 2016. 83: 76–83.

Harada, M.

M. Teshigawara, M. Harada, H. Tatsumoto, T. Aso et al. “Experimental Verification of Equilibrium Para-Hydrogen Levels in Hydrogen Moderators Irradiated by Spallation Neutrons at J-PARC”. Nucl. Instrum. Methods Phys. Res., Sect. B. 2016. 368: 66–70.

Hommeltoft, S.I.

T.C. Eisenschmid, R.U. Kirss, P.P. Deutsch, S.I. Hommeltoft et al. “Para Hydrogen Induced Polarization in Hydrogenation Reactions”. J. Am. Chem. Soc. 1987. 109(26): 8089–8091.

Hövener, J.B.

J.B. Hövener, S. Bär, J. Leupold, K. Jenne et al. “A Continuous-Flow, High-Throughput, High-Pressure Parahydrogen Converter for Hyperpolarization in a Clinical Setting”. NMR Biomed. 2013. 26(2): 124–131.

Hunt, J.L.

J.L. Hunt, J.D. Poll, and L. Wolniewicz “Ab Initio Calculation of Properties of the Neutral Diatomic Hydrogen Molecules H2, HD, D2, HT, DT and T2. Can. J. Phys. 1984. 62: 1719–1723.

Ilisca, E.

E. Ilisca “Ortho-Para Conversion of Hydrogen Molecules Physisorbed on Surfaces”. Prog. Surf. Sci. 1992. 41: 217–335.

Jackson, S.

P.M. Richardson, S. Jackson, A.J. Parrott, A. Nordon et al. “A Simple Hand-Held Magnet Array for Efficient and Reproducible SABRE Hyperpolarisation Using Manual Sample Shaking”. Magn. Reson. Chem. 2018. 56: 641–650.

Jacobsen, R.T.

J.W. Leachman, R.T. Jacobsen, S.G. Penoncello, E.W. Lemmon “Fundamental Equations of State for Parahydrogen, Normal Hydrogen, and Orthohydrogen”. J. Phys. Chem. Ref. Data. 2009. 38(3): 721–748.

Jenne, K.

J.B. Hövener, S. Bär, J. Leupold, K. Jenne et al. “A Continuous-Flow, High-Throughput, High-Pressure Parahydrogen Converter for Hyperpolarization in a Clinical Setting”. NMR Biomed. 2013. 26(2): 124–131.

Kempf, J.G.

I. Reile, R.L.E.G. Aspers, J.M. Tyburn, J.G. Kempf et al. “DOSY Analysis of Micromolar Analytes: Resolving Dilute Mixtures by SABRE Hyperpolarization”. Angew. Chem. Int. Ed. 2017. 56: 9174–9177.

Kiefer, J.

J. Kiefer “Recent Advances in the Characterization of Gaseous and Liquid Fuels by Vibrational Spectroscopy”. Energies. 2015. 8: 3165–3197.

S.C. Eichmann, M. Weschta, J. Kiefer, T. Seeger et al. “Characterization of a Fast Gas Analyzer Based on Raman Scattering for the Analysis of Synthesis Gas”. Rev. Sci. Instrum. 2010. 81(12): 125104.

Kirss, R.U.

T.C. Eisenschmid, R.U. Kirss, P.P. Deutsch, S.I. Hommeltoft et al. “Para Hydrogen Induced Polarization in Hydrogenation Reactions”. J. Am. Chem. Soc. 1987. 109(26): 8089–8091.

Knudson, J.N.

L.M. Sutherland, J.N. Knudson, M. Mocko, R.M. Renneke “Practical In-Situ Determination of Ortho-Para Hydrogen Ratios Via Fiber-Optic Based Raman Spectroscopy”. Nucl. Instrum. Methods Phys. Res., Sect. A. 2016. 810: 182–185.

Kohno, M.

N. Sakoda, K. Shindo, K. Shinzato, M. Kohno et al. “Review of the Thermodynamic Properties of Hydrogen Based on Existing Equations of State”. Int. J. Thermophys. 2010. 31(2): 276–296.

Leachman, J.W.

J.W. Leachman, R.T. Jacobsen, S.G. Penoncello, E.W. Lemmon “Fundamental Equations of State for Parahydrogen, Normal Hydrogen, and Orthohydrogen”. J. Phys. Chem. Ref. Data. 2009. 38(3): 721–748.

Lemmon, E.W.

J.W. Leachman, R.T. Jacobsen, S.G. Penoncello, E.W. Lemmon “Fundamental Equations of State for Parahydrogen, Normal Hydrogen, and Orthohydrogen”. J. Phys. Chem. Ref. Data. 2009. 38(3): 721–748.

Leupold, J.

J.B. Hövener, S. Bär, J. Leupold, K. Jenne et al. “A Continuous-Flow, High-Throughput, High-Pressure Parahydrogen Converter for Hyperpolarization in a Clinical Setting”. NMR Biomed. 2013. 26(2): 124–131.

Lloyd, L.S.

L.S. Lloyd, R.W. Adams, M. Bernstein, S. Coombes et al. “Utilization of SABRE Derived Hyperpolarization to Detect Low Concentration Analytes via 1D- and 2D-NMR Methods”. J. Am. Chem. Soc. 2012. 134: 12904–12907.

Matrosov, I.I.

D.V. Petrov, I.I. Matrosov “Pressure Dependence of the Raman Signal Intensity in High-Pressure Gases”. J. Raman. Spectrosc. 2017. 48: 474–478.

D.V. Petrov, I.I. Matrosov “Raman Gas Analyzer (RGA): Natural Gas Measurements”. Appl. Spectrosc. 2016. 70(10): 1770–1776.

Matsumoto, M.

M. Matsumoto, J.H. Espenson “Kinetics of the Interconversion of Parahydrogen and Orthohydrogen Catalyzed by Paramagnetic Complex Ions”. J. Am. Chem. Soc. 2005. 127(32): 11447–11453.

Matthews, M.J.

G. Petitpas, S.M. Aceves, M.J. Matthews, J.R. Smith “Para-H2 to Ortho-H2 Conversion in a Full-Scale Automotive Cryogenic Pressurized Hydrogen Storage up to 345 Bar”. Int. J. Hydrogen. Energy. 2014. 39(12): 6533–6547.

M.J. Matthews, G. Petitpas, and S.M. Aceves “A Study of Spin Isomer Conversion Kinetics in Supercritical Fluid Hydrogen for Cryogenic Fuel Storage Technologies”. Appl. Phys. Lett. 2011. 99(8): 1–4.

McTague, J.P.

P.A. Fleury, J.P. McTague “Molecular Interactions in the Condensed Phases of Ortho-Para Hydrogen Mixtures”. Phys. Rev. 1975. 12(1): 317–326.

Mewis, R.E.

R.E. Mewis, K.D. Atkinson, M.J. Cowley, S.B. Duckett et al. “Probing Signal Amplification by Reversible Exchange Using an NMR Flow System”. Magn. Reson. Chem. 2014. 52(February): 358–369.

S.B. Duckett, R.E. Mewis “Application of Parahydrogen Induced Polarization Techniques in NMR Spectroscopy and Imaging”. Acc. Chem. Res. 2012. 45(8): 1247–1257.

Mewis, R.W.

R.A. Green, R.W. Adams, S.B. Duckett, R.W. Mewis et al. “The Theory and Practice of Hyperpolarization in Magnetic Resonance Using Parahydrogen”. Prog. Nucl. Magn. Reson. Spectrosc. 2012. 67: 1–48.

Miyamoto, Y.

B.A. Tom, S. Bhasker, Y. Miyamoto, T. Momose et al. “Producing and Quantifying Enriched Para-H2”. Rev. Sci. Instrum. 2009. 80(1): 016108.

Mocko, M.

L.M. Sutherland, J.N. Knudson, M. Mocko, R.M. Renneke “Practical In-Situ Determination of Ortho-Para Hydrogen Ratios Via Fiber-Optic Based Raman Spectroscopy”. Nucl. Instrum. Methods Phys. Res., Sect. A. 2016. 810: 182–185.

Momose, T.

B.A. Tom, S. Bhasker, Y. Miyamoto, T. Momose et al. “Producing and Quantifying Enriched Para-H2”. Rev. Sci. Instrum. 2009. 80(1): 016108.

Nalbandian, R.

A. Gamliel, H. Allouche-Arnon, R. Nalbandian, C.M. Barzilay et al. “An Apparatus for Production of Isotopically and Spin-Enriched Hydrogen for Induced Polarization Studies”. Appl. Magn. Reson. 2010. 39(4): 329–345.

Natterer, J.

J. Natterer, J. Bargon “Parahydrogen Induced Polarization”. Prog. Nucl. Magn. Reson. Spectrosc. 1997. 31: 293–315.

Nordon, A.

P.M. Richardson, S. Jackson, A.J. Parrott, A. Nordon et al. “A Simple Hand-Held Magnet Array for Efficient and Reproducible SABRE Hyperpolarisation Using Manual Sample Shaking”. Magn. Reson. Chem. 2018. 56: 641–650.

P.M. Richardson, A.J. Parrott, O. Semenova, A. Nordon et al. “SABRE Hyperpolarization Enables High-Sensitivity 1H and 13C Benchtop NMR Spectroscopy”. Analyst. 2018. 143: 3442–3450.

Norris, J.O.W.

T.W. Bradshaw, J.O.W. Norris “Observations on the Use of a Thermal Conductivity Cell to Measure the Para Hydrogen Concentration in a Mixture of Para and Ortho Hydrogen Gas”. Rev. Sci. Instrum. 1987. 58(1): 83–85.

Parrott, A.J.

P.M. Richardson, A.J. Parrott, O. Semenova, A. Nordon et al. “SABRE Hyperpolarization Enables High-Sensitivity 1H and 13C Benchtop NMR Spectroscopy”. Analyst. 2018. 143: 3442–3450.

P.M. Richardson, S. Jackson, A.J. Parrott, A. Nordon et al. “A Simple Hand-Held Magnet Array for Efficient and Reproducible SABRE Hyperpolarisation Using Manual Sample Shaking”. Magn. Reson. Chem. 2018. 56: 641–650.

Penoncello, S.G.

J.W. Leachman, R.T. Jacobsen, S.G. Penoncello, E.W. Lemmon “Fundamental Equations of State for Parahydrogen, Normal Hydrogen, and Orthohydrogen”. J. Phys. Chem. Ref. Data. 2009. 38(3): 721–748.

Petitpas, G.

G. Petitpas, S.M. Aceves, M.J. Matthews, J.R. Smith “Para-H2 to Ortho-H2 Conversion in a Full-Scale Automotive Cryogenic Pressurized Hydrogen Storage up to 345 Bar”. Int. J. Hydrogen. Energy. 2014. 39(12): 6533–6547.

M.J. Matthews, G. Petitpas, and S.M. Aceves “A Study of Spin Isomer Conversion Kinetics in Supercritical Fluid Hydrogen for Cryogenic Fuel Storage Technologies”. Appl. Phys. Lett. 2011. 99(8): 1–4.

Petrov, D.V.

D.V. Petrov, I.I. Matrosov “Pressure Dependence of the Raman Signal Intensity in High-Pressure Gases”. J. Raman. Spectrosc. 2017. 48: 474–478.

D.V. Petrov, I.I. Matrosov “Raman Gas Analyzer (RGA): Natural Gas Measurements”. Appl. Spectrosc. 2016. 70(10): 1770–1776.

Poll, J.D.

J.L. Hunt, J.D. Poll, and L. Wolniewicz “Ab Initio Calculation of Properties of the Neutral Diatomic Hydrogen Molecules H2, HD, D2, HT, DT and T2. Can. J. Phys. 1984. 62: 1719–1723.

Ramanathan, N.

K. Sundararajan, K. Sankaran, N. Ramanathan, R. Gopi “Production and Characterization of Para-Hydrogen Gas for Matrix Isolation Infrared Spectroscopy”. J. Mol. Struct. 2016. 1117: 181–191.

Reile, I.

I. Reile, R.L.E.G. Aspers, J.M. Tyburn, J.G. Kempf et al. “DOSY Analysis of Micromolar Analytes: Resolving Dilute Mixtures by SABRE Hyperpolarization”. Angew. Chem. Int. Ed. 2017. 56: 9174–9177.

Renneke, R.M.

L.M. Sutherland, J.N. Knudson, M. Mocko, R.M. Renneke “Practical In-Situ Determination of Ortho-Para Hydrogen Ratios Via Fiber-Optic Based Raman Spectroscopy”. Nucl. Instrum. Methods Phys. Res., Sect. A. 2016. 810: 182–185.

Richardson, P.M.

P.M. Richardson, A.J. Parrott, O. Semenova, A. Nordon et al. “SABRE Hyperpolarization Enables High-Sensitivity 1H and 13C Benchtop NMR Spectroscopy”. Analyst. 2018. 143: 3442–3450.

P.M. Richardson, S. Jackson, A.J. Parrott, A. Nordon et al. “A Simple Hand-Held Magnet Array for Efficient and Reproducible SABRE Hyperpolarisation Using Manual Sample Shaking”. Magn. Reson. Chem. 2018. 56: 641–650.

Sakoda, N.

N. Sakoda, K. Shindo, K. Shinzato, M. Kohno et al. “Review of the Thermodynamic Properties of Hydrogen Based on Existing Equations of State”. Int. J. Thermophys. 2010. 31(2): 276–296.

Sankaran, K.

K. Sundararajan, K. Sankaran, N. Ramanathan, R. Gopi “Production and Characterization of Para-Hydrogen Gas for Matrix Isolation Infrared Spectroscopy”. J. Mol. Struct. 2016. 1117: 181–191.

Seeger, T.

S.C. Eichmann, M. Weschta, J. Kiefer, T. Seeger et al. “Characterization of a Fast Gas Analyzer Based on Raman Scattering for the Analysis of Synthesis Gas”. Rev. Sci. Instrum. 2010. 81(12): 125104.

Semenova, O.

P.M. Richardson, A.J. Parrott, O. Semenova, A. Nordon et al. “SABRE Hyperpolarization Enables High-Sensitivity 1H and 13C Benchtop NMR Spectroscopy”. Analyst. 2018. 143: 3442–3450.

Shindo, K.

N. Sakoda, K. Shindo, K. Shinzato, M. Kohno et al. “Review of the Thermodynamic Properties of Hydrogen Based on Existing Equations of State”. Int. J. Thermophys. 2010. 31(2): 276–296.

Shinzato, K.

N. Sakoda, K. Shindo, K. Shinzato, M. Kohno et al. “Review of the Thermodynamic Properties of Hydrogen Based on Existing Equations of State”. Int. J. Thermophys. 2010. 31(2): 276–296.

Sleigh, C.J.

S.B. Duckett, C.J. Sleigh “Applications of the Parahydrogen Phenomenon: A Chemical Perspective”. Prog. Nucl. Magn. Reson. Spectrosc. 1999. 34(1): 71–92.

Smith, J.R.

G. Petitpas, S.M. Aceves, M.J. Matthews, J.R. Smith “Para-H2 to Ortho-H2 Conversion in a Full-Scale Automotive Cryogenic Pressurized Hydrogen Storage up to 345 Bar”. Int. J. Hydrogen. Energy. 2014. 39(12): 6533–6547.

Sundararajan, K.

K. Sundararajan, K. Sankaran, N. Ramanathan, R. Gopi “Production and Characterization of Para-Hydrogen Gas for Matrix Isolation Infrared Spectroscopy”. J. Mol. Struct. 2016. 1117: 181–191.

Sutherland, L.M.

L.M. Sutherland, J.N. Knudson, M. Mocko, R.M. Renneke “Practical In-Situ Determination of Ortho-Para Hydrogen Ratios Via Fiber-Optic Based Raman Spectroscopy”. Nucl. Instrum. Methods Phys. Res., Sect. A. 2016. 810: 182–185.

Tam, S.

S. Tam, M.E. Fajardo “Ortho/Para Hydrogen Converter for Rapid Deposition Matrix Isolation Spectroscopy”. Rev. Sci. Instrum. 1999. 70(4): 1926–1932.

Tatsumoto, H.

M. Teshigawara, M. Harada, H. Tatsumoto, T. Aso et al. “Experimental Verification of Equilibrium Para-Hydrogen Levels in Hydrogen Moderators Irradiated by Spallation Neutrons at J-PARC”. Nucl. Instrum. Methods Phys. Res., Sect. B. 2016. 368: 66–70.

Teshigawara, M.

M. Teshigawara, M. Harada, H. Tatsumoto, T. Aso et al. “Experimental Verification of Equilibrium Para-Hydrogen Levels in Hydrogen Moderators Irradiated by Spallation Neutrons at J-PARC”. Nucl. Instrum. Methods Phys. Res., Sect. B. 2016. 368: 66–70.

Tom, B.A.

B.A. Tom, S. Bhasker, Y. Miyamoto, T. Momose et al. “Producing and Quantifying Enriched Para-H2”. Rev. Sci. Instrum. 2009. 80(1): 016108.

Tyburn, J.M.

I. Reile, R.L.E.G. Aspers, J.M. Tyburn, J.G. Kempf et al. “DOSY Analysis of Micromolar Analytes: Resolving Dilute Mixtures by SABRE Hyperpolarization”. Angew. Chem. Int. Ed. 2017. 56: 9174–9177.

Walaszek, B.

G. Buntkowsky, B. Walaszek, A. Adamczyk, Y. Xu et al. Mechanism of Nuclear Spin Initiated Para-H2 to Ortho-H2 Conversion”. Phys. Chem. Chem. Phys. 2006. 8(16): 1929–1935.

Weschta, M.

S.C. Eichmann, M. Weschta, J. Kiefer, T. Seeger et al. “Characterization of a Fast Gas Analyzer Based on Raman Scattering for the Analysis of Synthesis Gas”. Rev. Sci. Instrum. 2010. 81(12): 125104.

Wolniewicz, L.

J.L. Hunt, J.D. Poll, and L. Wolniewicz “Ab Initio Calculation of Properties of the Neutral Diatomic Hydrogen Molecules H2, HD, D2, HT, DT and T2. Can. J. Phys. 1984. 62: 1719–1723.

Wood, N.J.

S.B. Duckett, N.J. Wood “Parahydrogen-Based NMR Methods as a Mechanistic Probe in Inorganic Chemistry”. Coord. Chem. Rev. 2008. 252(21–22): 2278–2291.

Xu, Y.

G. Buntkowsky, B. Walaszek, A. Adamczyk, Y. Xu et al. Mechanism of Nuclear Spin Initiated Para-H2 to Ortho-H2 Conversion”. Phys. Chem. Chem. Phys. 2006. 8(16): 1929–1935.

Acc. Chem. Res (2)

S.B. Duckett, R.E. Mewis “Application of Parahydrogen Induced Polarization Techniques in NMR Spectroscopy and Imaging”. Acc. Chem. Res. 2012. 45(8): 1247–1257.

R. Eisenberg “Parahydrogen-Induced Polarization: A New Spin on Reactions with H2”. Acc. Chem. Res. 1991. 24(4): 110–116.

Analyst (1)

P.M. Richardson, A.J. Parrott, O. Semenova, A. Nordon et al. “SABRE Hyperpolarization Enables High-Sensitivity 1H and 13C Benchtop NMR Spectroscopy”. Analyst. 2018. 143: 3442–3450.

Angew. Chem. Int. Ed (1)

I. Reile, R.L.E.G. Aspers, J.M. Tyburn, J.G. Kempf et al. “DOSY Analysis of Micromolar Analytes: Resolving Dilute Mixtures by SABRE Hyperpolarization”. Angew. Chem. Int. Ed. 2017. 56: 9174–9177.

Appl. Magn. Reson (1)

A. Gamliel, H. Allouche-Arnon, R. Nalbandian, C.M. Barzilay et al. “An Apparatus for Production of Isotopically and Spin-Enriched Hydrogen for Induced Polarization Studies”. Appl. Magn. Reson. 2010. 39(4): 329–345.

Appl. Phys. Lett (1)

M.J. Matthews, G. Petitpas, and S.M. Aceves “A Study of Spin Isomer Conversion Kinetics in Supercritical Fluid Hydrogen for Cryogenic Fuel Storage Technologies”. Appl. Phys. Lett. 2011. 99(8): 1–4.

Appl. Spectrosc (1)

D.V. Petrov, I.I. Matrosov “Raman Gas Analyzer (RGA): Natural Gas Measurements”. Appl. Spectrosc. 2016. 70(10): 1770–1776.

Can. J. Phys (1)

J.L. Hunt, J.D. Poll, and L. Wolniewicz “Ab Initio Calculation of Properties of the Neutral Diatomic Hydrogen Molecules H2, HD, D2, HT, DT and T2. Can. J. Phys. 1984. 62: 1719–1723.

Coord. Chem. Rev (1)

S.B. Duckett, N.J. Wood “Parahydrogen-Based NMR Methods as a Mechanistic Probe in Inorganic Chemistry”. Coord. Chem. Rev. 2008. 252(21–22): 2278–2291.

Dalton Trans (1)

D. Blazina, S.B. Duckett, J.P. Dunne, C. Godard “Applications of the Parahydrogen Phenomenon in Inorganic Chemistry”. Dalton Trans. 2004. 17, 2601–2609.

Energies (1)

J. Kiefer “Recent Advances in the Characterization of Gaseous and Liquid Fuels by Vibrational Spectroscopy”. Energies. 2015. 8: 3165–3197.

Int. J. Hydrogen. Energy (1)

G. Petitpas, S.M. Aceves, M.J. Matthews, J.R. Smith “Para-H2 to Ortho-H2 Conversion in a Full-Scale Automotive Cryogenic Pressurized Hydrogen Storage up to 345 Bar”. Int. J. Hydrogen. Energy. 2014. 39(12): 6533–6547.

Int. J. Thermophys (1)

N. Sakoda, K. Shindo, K. Shinzato, M. Kohno et al. “Review of the Thermodynamic Properties of Hydrogen Based on Existing Equations of State”. Int. J. Thermophys. 2010. 31(2): 276–296.

J. Am. Chem. Soc (3)

L.S. Lloyd, R.W. Adams, M. Bernstein, S. Coombes et al. “Utilization of SABRE Derived Hyperpolarization to Detect Low Concentration Analytes via 1D- and 2D-NMR Methods”. J. Am. Chem. Soc. 2012. 134: 12904–12907.

M. Matsumoto, J.H. Espenson “Kinetics of the Interconversion of Parahydrogen and Orthohydrogen Catalyzed by Paramagnetic Complex Ions”. J. Am. Chem. Soc. 2005. 127(32): 11447–11453.

T.C. Eisenschmid, R.U. Kirss, P.P. Deutsch, S.I. Hommeltoft et al. “Para Hydrogen Induced Polarization in Hydrogenation Reactions”. J. Am. Chem. Soc. 1987. 109(26): 8089–8091.

J. Magn. Reson (1)

B. Feng, A.M. Coffey, R.D. Colon, E.Y. Chekmenev et al. “A Pulsed Injection Parahydrogen Generator and Techniques for Quantifying Enrichment”. J. Magn. Reson. 2012. 214: 258–262.

J. Mol. Struct (1)

K. Sundararajan, K. Sankaran, N. Ramanathan, R. Gopi “Production and Characterization of Para-Hydrogen Gas for Matrix Isolation Infrared Spectroscopy”. J. Mol. Struct. 2016. 1117: 181–191.

J. Phys. Chem. Ref. Data (1)

J.W. Leachman, R.T. Jacobsen, S.G. Penoncello, E.W. Lemmon “Fundamental Equations of State for Parahydrogen, Normal Hydrogen, and Orthohydrogen”. J. Phys. Chem. Ref. Data. 2009. 38(3): 721–748.

J. Raman. Spectrosc (1)

D.V. Petrov, I.I. Matrosov “Pressure Dependence of the Raman Signal Intensity in High-Pressure Gases”. J. Raman. Spectrosc. 2017. 48: 474–478.

Magn. Reson. Chem (2)

R.E. Mewis, K.D. Atkinson, M.J. Cowley, S.B. Duckett et al. “Probing Signal Amplification by Reversible Exchange Using an NMR Flow System”. Magn. Reson. Chem. 2014. 52(February): 358–369.

P.M. Richardson, S. Jackson, A.J. Parrott, A. Nordon et al. “A Simple Hand-Held Magnet Array for Efficient and Reproducible SABRE Hyperpolarisation Using Manual Sample Shaking”. Magn. Reson. Chem. 2018. 56: 641–650.

NMR Biomed (1)

J.B. Hövener, S. Bär, J. Leupold, K. Jenne et al. “A Continuous-Flow, High-Throughput, High-Pressure Parahydrogen Converter for Hyperpolarization in a Clinical Setting”. NMR Biomed. 2013. 26(2): 124–131.

Nucl. Instrum. Methods Phys. Res., Sect. A (1)

L.M. Sutherland, J.N. Knudson, M. Mocko, R.M. Renneke “Practical In-Situ Determination of Ortho-Para Hydrogen Ratios Via Fiber-Optic Based Raman Spectroscopy”. Nucl. Instrum. Methods Phys. Res., Sect. A. 2016. 810: 182–185.

Nucl. Instrum. Methods Phys. Res., Sect. B (1)

M. Teshigawara, M. Harada, H. Tatsumoto, T. Aso et al. “Experimental Verification of Equilibrium Para-Hydrogen Levels in Hydrogen Moderators Irradiated by Spallation Neutrons at J-PARC”. Nucl. Instrum. Methods Phys. Res., Sect. B. 2016. 368: 66–70.

Phys. Chem. Chem. Phys (1)

G. Buntkowsky, B. Walaszek, A. Adamczyk, Y. Xu et al. Mechanism of Nuclear Spin Initiated Para-H2 to Ortho-H2 Conversion”. Phys. Chem. Chem. Phys. 2006. 8(16): 1929–1935.

Phys. Rev (1)

P.A. Fleury, J.P. McTague “Molecular Interactions in the Condensed Phases of Ortho-Para Hydrogen Mixtures”. Phys. Rev. 1975. 12(1): 317–326.

Prog. Nucl. Magn. Reson. Spectrosc (2)

J. Natterer, J. Bargon “Parahydrogen Induced Polarization”. Prog. Nucl. Magn. Reson. Spectrosc. 1997. 31: 293–315.

S.B. Duckett, C.J. Sleigh “Applications of the Parahydrogen Phenomenon: A Chemical Perspective”. Prog. Nucl. Magn. Reson. Spectrosc. 1999. 34(1): 71–92.

Prog. Surf. Sci (1)

E. Ilisca “Ortho-Para Conversion of Hydrogen Molecules Physisorbed on Surfaces”. Prog. Surf. Sci. 1992. 41: 217–335.

Rev. Sci. Instrum (4)

S. Tam, M.E. Fajardo “Ortho/Para Hydrogen Converter for Rapid Deposition Matrix Isolation Spectroscopy”. Rev. Sci. Instrum. 1999. 70(4): 1926–1932.

T.W. Bradshaw, J.O.W. Norris “Observations on the Use of a Thermal Conductivity Cell to Measure the Para Hydrogen Concentration in a Mixture of Para and Ortho Hydrogen Gas”. Rev. Sci. Instrum. 1987. 58(1): 83–85.

B.A. Tom, S. Bhasker, Y. Miyamoto, T. Momose et al. “Producing and Quantifying Enriched Para-H2”. Rev. Sci. Instrum. 2009. 80(1): 016108.

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