PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 1556190-3 1992 Hydrogen consumption varied directly with PH2, and methanogenic feces consumed H2 far more rapidly than did nonmethanogenic feces. Hydrogen 0-8 polyhomeotic homolog 2 Homo sapiens 42-45 1556190-4 1992 At low PH2, H2 production greatly exceeded consumption and there was negligible accumulation of the products of H2 catabolism, methane and sulfide. Hydrogen 12-14 polyhomeotic homolog 2 Homo sapiens 7-10 1556190-8 1992 We conclude that most H2 produced by colonic bacteria is consumed and methanogenesis and fecal stirring (via its influence on fecal PH2) are critical determinants of H2 consumption and, hence, net H2 production. Hydrogen 22-24 polyhomeotic homolog 2 Homo sapiens 132-135 34406748-4 2021 We identified the system propargyl alcohol + pH2 allyl alcohol to yield 1H polarization in excess of P 13% by using only 50% enriched pH2 at a pressure of 1 bar. Hydrogen 74-76 polyhomeotic homolog 2 Homo sapiens 45-48 34406748-4 2021 We identified the system propargyl alcohol + pH2 allyl alcohol to yield 1H polarization in excess of P 13% by using only 50% enriched pH2 at a pressure of 1 bar. Hydrogen 74-76 polyhomeotic homolog 2 Homo sapiens 138-141 33126626-2 2020 Through the detailed study of graphene growth on liquid Sn using atmospheric pressure CVD (APCVD), the quality of graphene has been found to have a close relationship with hydrogen flow rate that reflects on hydrogen partial pressure inside the reactor (PH2) and hydrogen solubility of the growth substrates. Hydrogen 172-180 polyhomeotic homolog 2 Homo sapiens 254-257 33126626-2 2020 Through the detailed study of graphene growth on liquid Sn using atmospheric pressure CVD (APCVD), the quality of graphene has been found to have a close relationship with hydrogen flow rate that reflects on hydrogen partial pressure inside the reactor (PH2) and hydrogen solubility of the growth substrates. Hydrogen 208-216 polyhomeotic homolog 2 Homo sapiens 254-257 33126626-2 2020 Through the detailed study of graphene growth on liquid Sn using atmospheric pressure CVD (APCVD), the quality of graphene has been found to have a close relationship with hydrogen flow rate that reflects on hydrogen partial pressure inside the reactor (PH2) and hydrogen solubility of the growth substrates. Hydrogen 208-216 polyhomeotic homolog 2 Homo sapiens 254-257 33138410-1 2020 The reaction of hydrogen atoms (H) with pyrrole (C4H4NH) in solid para-hydrogen (p-H2) matrices at 3.2 K has been studied by infrared spectroscopy. Hydrogen 16-24 polyhomeotic homolog 2 Homo sapiens 81-85 31508642-2 2019 These regimes are defined by the relative rate of reaction, k, compared to deltaomega, the frequency of the NMR signal oscillations associated with the coherent evolution of the hyperpolarised 1H NMR signals created after para-hydrogen (p-H2) addition during the pump-probe delay. Hydrogen 193-195 polyhomeotic homolog 2 Homo sapiens 237-241 31864267-1 2019 We investigated the reaction of methyl formate, HC(O)OCH3, with hydrogen atoms in solid para-hydrogen (p-H2) at 1.74 and 3.3 K with infrared absorption spectroscopy. Hydrogen 64-72 polyhomeotic homolog 2 Homo sapiens 103-107 31864267-1 2019 We investigated the reaction of methyl formate, HC(O)OCH3, with hydrogen atoms in solid para-hydrogen (p-H2) at 1.74 and 3.3 K with infrared absorption spectroscopy. Hydrogen 88-101 polyhomeotic homolog 2 Homo sapiens 103-107 31864267-2 2019 Hydrogen atoms were produced either upon direct photolysis of HC(O)OCH3 at 193 nm or upon irradiation of Cl2, codeposited with HC(O)OCH3 in p-H2, with light at 365 nm to produce Cl atoms that react with the p-H2 host via the reaction Cl + H2 (nu = 1) HCl + H induced by subsequent IR irradiation of the p-H2 matrix. Hydrogen 0-8 polyhomeotic homolog 2 Homo sapiens 140-144 31864267-2 2019 Hydrogen atoms were produced either upon direct photolysis of HC(O)OCH3 at 193 nm or upon irradiation of Cl2, codeposited with HC(O)OCH3 in p-H2, with light at 365 nm to produce Cl atoms that react with the p-H2 host via the reaction Cl + H2 (nu = 1) HCl + H induced by subsequent IR irradiation of the p-H2 matrix. Hydrogen 0-8 polyhomeotic homolog 2 Homo sapiens 207-211 31864267-2 2019 Hydrogen atoms were produced either upon direct photolysis of HC(O)OCH3 at 193 nm or upon irradiation of Cl2, codeposited with HC(O)OCH3 in p-H2, with light at 365 nm to produce Cl atoms that react with the p-H2 host via the reaction Cl + H2 (nu = 1) HCl + H induced by subsequent IR irradiation of the p-H2 matrix. Hydrogen 0-8 polyhomeotic homolog 2 Homo sapiens 207-211 32462154-1 2020 The stepwise solvation of various cationic coronene oligomers by para-hydrogen (p-H2) molecules was computationally investigated using a united-atom model for the p-H2 molecules and the Silvera-Goldman potential, together with a polarizable description for the interaction with the hydrocarbon molecules. Hydrogen 70-78 polyhomeotic homolog 2 Homo sapiens 80-84 32129366-2 2020 We utilized the advantages of a para-hydrogen (p-H2) quantum-solid matrix host to perform efficient reactions of hydrogen atoms with CH3CONH2. Hydrogen 37-45 polyhomeotic homolog 2 Homo sapiens 47-51 32129366-2 2020 We utilized the advantages of a para-hydrogen (p-H2) quantum-solid matrix host to perform efficient reactions of hydrogen atoms with CH3CONH2. Hydrogen 113-121 polyhomeotic homolog 2 Homo sapiens 47-51 31508642-2 2019 These regimes are defined by the relative rate of reaction, k, compared to deltaomega, the frequency of the NMR signal oscillations associated with the coherent evolution of the hyperpolarised 1H NMR signals created after para-hydrogen (p-H2) addition during the pump-probe delay. Hydrogen 227-235 polyhomeotic homolog 2 Homo sapiens 237-241 30059190-5 2018 The prerequisites for preserving hyperpolarization upon separation of the two hydrogen atoms of p-H2 are demonstrated by theoretical examinations of the boundary conditions for the hyperpolarization experiments in accordance with the OneH-PHIP theory. Hydrogen 78-86 polyhomeotic homolog 2 Homo sapiens 96-100 31370543-2 2019 We report the infrared (IR) spectrum of mono-hydrogenated corannulene (HC20H10) in solid para-hydrogen (p-H2). Hydrogen 89-102 polyhomeotic homolog 2 Homo sapiens 104-108 31370543-6 2019 Alternative hydrogenation was achieved with H atoms produced photochemically in the infrared-induced reaction Cl + H2 (v = 1) H + HCl in a Cl2/C20H10/p-H2 matrix. Hydrogen 115-117 polyhomeotic homolog 2 Homo sapiens 145-156 30303501-1 2018 para-Hydrogen (p-H2) induced polarisation (PHIP) is an increasingly popular method for sensitivity enhancement in NMR spectroscopy. Hydrogen 0-13 polyhomeotic homolog 2 Homo sapiens 15-19 30303501-5 2018 A linear relationship was found between p-H2 enrichment and analyte 1H hyperpolarisation for a range of molecules, polarisation transfer catalysts, NMR detection fields and for both the SABRE and SABRE-Relay transfer mechanisms over the range 29-99% p-H2 purity. Hydrogen 68-70 polyhomeotic homolog 2 Homo sapiens 40-44 30303501-5 2018 A linear relationship was found between p-H2 enrichment and analyte 1H hyperpolarisation for a range of molecules, polarisation transfer catalysts, NMR detection fields and for both the SABRE and SABRE-Relay transfer mechanisms over the range 29-99% p-H2 purity. Hydrogen 68-70 polyhomeotic homolog 2 Homo sapiens 250-254 29625356-2 2018 Even though the "Signal Amplification by Reversible Exchange" (SABRE) approach uses para-enriched hydrogen, p-H2, to repeatedly achieve high polarization levels on target molecules without altering their chemical structure, such studies are often limited to batch experiments in NMR tubes. Hydrogen 98-106 polyhomeotic homolog 2 Homo sapiens 108-112 29432020-1 2018 Signal Amplification by Reversible Exchange (SABRE) is used to switch on the latent singlet spin order of para-hydrogen (p-H2) so that it can hyperpolarize a substrate (sub = nicotinamide, nicotinate, niacin, pyrimidine, and pyrazine). Hydrogen 106-119 polyhomeotic homolog 2 Homo sapiens 121-125 29733191-3 2018 We have recently applied this technique to condensed matter samples, one of which is solid para-hydrogen ( p-H2). Hydrogen 91-104 polyhomeotic homolog 2 Homo sapiens 107-111 29494164-8 2018 A clear tunneling splitting is observed for the torsional motion of the two hydrogen molecules ( pH2, HD, or oD2) on a ring about the OCS molecular axis, whereas no tunneling splitting is found in OCS- pH2-He or OCS-(He)2 due to a much lower torsional barrier. Hydrogen 76-84 polyhomeotic homolog 2 Homo sapiens 97-100 28967028-1 2018 para-Hydrogen (p-H2) serves as a new host in matrix-isolation experiments for an investigation of species of astrochemical interest. Hydrogen 0-13 polyhomeotic homolog 2 Homo sapiens 15-19 28474853-1 2017 At 80 GPa, phases with the PH2 stoichiometry, which are composed of simple cubic like phosphorus layers capped with hydrogen atoms and layers of H2 molecules, are predicted to be important species contributing to the recently observed superconductivity in compressed phosphine. Hydrogen 116-124 polyhomeotic homolog 2 Homo sapiens 27-30 28892705-1 2017 In this study, the effect of reduced hydrogen partial pressure (PH2) on the generation of carboxylic acids from acidogenic fermentation of glucose was investigated. Hydrogen 37-45 polyhomeotic homolog 2 Homo sapiens 64-67 28682000-3 2017 In this work, we show a new approach based on para enriched hydrogen (p-H2 ) that enables the hyperpolarization of bulk water if a suitable catalytic system is employed. Hydrogen 60-68 polyhomeotic homolog 2 Homo sapiens 70-74 28616991-1 2017 Despite the fact that the para-hydrogen molecule (p-H2) and its isotopomers (o-D2 and p-T2) are commonly modeled as spherical objects due to the large separation between rotational states, there may be situations (e.g. adsorption in pores and on surfaces) in which such an approximation neglects important degrees of freedom (i.e. the rotational ones) and introduces uncontrolled biases in the predicted properties. Hydrogen 31-39 polyhomeotic homolog 2 Homo sapiens 50-54 28761933-4 2017 The butyrogenic reactor was operated at 37 C and pH 5.5 with a hydraulic retention time of 31 h and a low hydrogen partial pressure (PH2). Hydrogen 106-114 polyhomeotic homolog 2 Homo sapiens 133-136 28433034-1 2017 At ambient temperature, conversion from 100% enriched para-hydrogen (p-H2; singlet state) to ortho-hydrogen (o-H2; triplet state) leads necessarily to the thermodynamic equilibrium proportions: 75% of o-H2 and 25% of p-H2. Hydrogen 54-67 polyhomeotic homolog 2 Homo sapiens 69-73 28604870-2 2017 We present the results of the reaction H + HONO in solid para-hydrogen (p-H2) at 3.3 K investigated with infrared spectra. Hydrogen 57-70 polyhomeotic homolog 2 Homo sapiens 72-76 28604870-3 2017 Two methods that produced hydrogen atoms were the irradiation of HONO molecules in p-H2 at 365 nm to produce OH radicals that reacted readily with nearby H2 to produce mobile H atoms, and irradiation of Cl2 molecules (co-deposited with HONO) in p-H2 at 405 nm to produce Cl atoms that reacted, upon IR irradiation of the p-H2 matrix, readily with nearby H2 to produce mobile H atoms. Hydrogen 26-34 polyhomeotic homolog 2 Homo sapiens 83-87 28604870-3 2017 Two methods that produced hydrogen atoms were the irradiation of HONO molecules in p-H2 at 365 nm to produce OH radicals that reacted readily with nearby H2 to produce mobile H atoms, and irradiation of Cl2 molecules (co-deposited with HONO) in p-H2 at 405 nm to produce Cl atoms that reacted, upon IR irradiation of the p-H2 matrix, readily with nearby H2 to produce mobile H atoms. Hydrogen 26-34 polyhomeotic homolog 2 Homo sapiens 245-249 28604870-3 2017 Two methods that produced hydrogen atoms were the irradiation of HONO molecules in p-H2 at 365 nm to produce OH radicals that reacted readily with nearby H2 to produce mobile H atoms, and irradiation of Cl2 molecules (co-deposited with HONO) in p-H2 at 405 nm to produce Cl atoms that reacted, upon IR irradiation of the p-H2 matrix, readily with nearby H2 to produce mobile H atoms. Hydrogen 26-34 polyhomeotic homolog 2 Homo sapiens 245-249 28433034-1 2017 At ambient temperature, conversion from 100% enriched para-hydrogen (p-H2; singlet state) to ortho-hydrogen (o-H2; triplet state) leads necessarily to the thermodynamic equilibrium proportions: 75% of o-H2 and 25% of p-H2. Hydrogen 54-67 polyhomeotic homolog 2 Homo sapiens 217-221 28433034-1 2017 At ambient temperature, conversion from 100% enriched para-hydrogen (p-H2; singlet state) to ortho-hydrogen (o-H2; triplet state) leads necessarily to the thermodynamic equilibrium proportions: 75% of o-H2 and 25% of p-H2. Hydrogen 59-67 polyhomeotic homolog 2 Homo sapiens 69-73 28433034-1 2017 At ambient temperature, conversion from 100% enriched para-hydrogen (p-H2; singlet state) to ortho-hydrogen (o-H2; triplet state) leads necessarily to the thermodynamic equilibrium proportions: 75% of o-H2 and 25% of p-H2. Hydrogen 59-67 polyhomeotic homolog 2 Homo sapiens 217-221 28433034-5 2017 Also, as the para ortho conversion is monitored by proton nuclear magnetic resonance (NMR) of dissolved o-H2 (p-H2 is NMR-silent), one has to account for H2 exchange between the liquid phase and the gas phase within the NMR tube, as well as for dissolution effects. Hydrogen 106-108 polyhomeotic homolog 2 Homo sapiens 110-114 28183024-1 2017 SABRE (Signal Amplification By Reversible Exchange) is a nuclear spin hyperpolarization technique based on the reversible concurrent binding of small molecules and para-hydrogen (p-H2) to an iridium metal complex in solution. Hydrogen 169-177 polyhomeotic homolog 2 Homo sapiens 179-183 28346551-1 2017 We report infrared (IR) spectra of HSCS+, c-HSCS, HCS2-, and other species produced on electron bombardment of a mixture of CS2 and para-hydrogen (p-H2) during deposition at 3.2 K. After maintenance of the deposited matrix in darkness for 12 h, the intensities of the absorption lines of HSCS+ at 2477.2 (nu1), 1525.6 (nu2), and 919.6 cm-1 (nu3) decreased through neutralization of HSCS+ with trapped electrons. Hydrogen 137-145 polyhomeotic homolog 2 Homo sapiens 147-151 27783615-3 2016 Furthermore, the role of NAD, which is affected by hydrogen partial pressure (PH2), has often not been considered. Hydrogen 51-59 polyhomeotic homolog 2 Homo sapiens 78-81 27782413-1 2016 The addition reactions of chlorine atom with isobutene (i-C4H8) in solid para-hydrogen (p-H2) were investigated with infrared (IR) absorption spectra. Hydrogen 73-86 polyhomeotic homolog 2 Homo sapiens 88-92 27783615-12 2016 This theoretical investigation shows that thermodynamic control of PH2 on individual VFA produced and associated yield of hydrogen and methane cannot be explained without considering NADH oxidation. Hydrogen 122-130 polyhomeotic homolog 2 Homo sapiens 67-70 26747816-3 2016 The latter sequence arises because PH2 fragments are surprisingly mobile on Si(001) and can diffuse away from the third hydrogen atom that makes up the PH3 stoichiometry. Hydrogen 120-128 polyhomeotic homolog 2 Homo sapiens 35-38 27782629-1 2016 We have experimentally performed the coherent control of delocalized ro-vibrational wave packets (RVWs) of solid para-hydrogen (p-H2) by the wave packet interferometry (WPI) combined with coherent anti-Stokes Raman scattering (CARS). Hydrogen 113-126 polyhomeotic homolog 2 Homo sapiens 128-132 27394107-1 2016 We have employed electron bombardment during matrix deposition of CO2 (or (13)CO2, C(18)O2) and para-hydrogen (p-H2) at 3.2 K and recorded infrared (IR) spectra of t-HOCO(+), H(+)(CO2)2, HCO2 (-), CO2 (-), t-HOCO, and other species isolated in solid p-H2. Hydrogen 101-109 polyhomeotic homolog 2 Homo sapiens 111-115 26987665-4 2016 Low H2 partial pressure (PH2) tends to result in fast growth of dendritically shaped GSCs with multiple small adlayers, but high PH2 can modify the GSC shape into hexagons with single large adlayer nuclei. Hydrogen 4-6 polyhomeotic homolog 2 Homo sapiens 25-28 26859865-1 2016 SABRE (Signal Amplification By Reversible Exchange) nuclear spin hyperpolarization method can provide strongly enhanced NMR signals as a result of the reversible association of small molecules with para-hydrogen (p-H2) at an iridium metal complex. Hydrogen 198-211 polyhomeotic homolog 2 Homo sapiens 213-217 26263322-1 2015 We report that at ambient temperature and with 100% enriched para-hydrogen (p-H2) dissolved in organic solvents, paramagnetic spin catalysis of para ortho hydrogen conversion is accompanied at the onset by a negative ortho-hydrogen (o-H2) proton NMR signal. Hydrogen 61-74 polyhomeotic homolog 2 Homo sapiens 76-80 26332643-1 2015 Insights into the mechanism of the unusual trans-hydrogenation of internal alkynes catalyzed by {Cp*Ru} complexes were gained by para-hydrogen (p-H2 ) induced polarization (PHIP) transfer NMR spectroscopy. Hydrogen 129-142 polyhomeotic homolog 2 Homo sapiens 144-148 27478268-1 2015 Insights into the mechanism of the unusual trans-hydrogenation of internal alkynes catalyzed by {Cp*Ru} complexes were gained by para-hydrogen (p-H2) induced polarization (PHIP) transfer NMR spectroscopy. Hydrogen 129-142 polyhomeotic homolog 2 Homo sapiens 144-148 26263322-1 2015 We report that at ambient temperature and with 100% enriched para-hydrogen (p-H2) dissolved in organic solvents, paramagnetic spin catalysis of para ortho hydrogen conversion is accompanied at the onset by a negative ortho-hydrogen (o-H2) proton NMR signal. Hydrogen 66-74 polyhomeotic homolog 2 Homo sapiens 76-80 26263322-1 2015 We report that at ambient temperature and with 100% enriched para-hydrogen (p-H2) dissolved in organic solvents, paramagnetic spin catalysis of para ortho hydrogen conversion is accompanied at the onset by a negative ortho-hydrogen (o-H2) proton NMR signal. Hydrogen 157-165 polyhomeotic homolog 2 Homo sapiens 76-80 25399145-0 2014 Fully quantal calculation of H2 translation-rotation states in the (p-H2)2@5(12)6(4) clathrate hydrate inclusion compound. Hydrogen 29-31 polyhomeotic homolog 2 Homo sapiens 68-72 24811617-1 2014 Liquid para-hydrogen (p-H2) is a typical quantum liquid which exhibits strong nuclear quantum effects (NQEs) and thus anomalous static and dynamic properties. Hydrogen 7-20 polyhomeotic homolog 2 Homo sapiens 22-26 24985634-1 2014 We have recorded infrared spectra of acetyl radical (CH3CO) and CH3-CO complex in solid para-hydrogen (p-H2). Hydrogen 88-101 polyhomeotic homolog 2 Homo sapiens 103-107 24811617-2 2014 We propose a real-time simulation method of wave packet (WP) molecular dynamics (MD) based on non-empirical intra- and inter-molecular interactions of non-spherical hydrogen molecules, and apply it to condensed-phase p-H2. Hydrogen 165-173 polyhomeotic homolog 2 Homo sapiens 217-221 24811617-4 2014 The developed MD simulation for 100 ps with 1200 hydrogen molecules is realized at feasible computational cost, by which basic experimental properties of p-H2 liquid such as radial distribution functions, self-diffusion coefficients, and shear viscosities are all well reproduced. Hydrogen 49-57 polyhomeotic homolog 2 Homo sapiens 154-158 24475903-1 2014 SABRE is a nuclear spin hyperpolarization technique based on the reversible association of a substrate molecule and para-hydrogen (p-H2) to a metal complex. Hydrogen 121-129 polyhomeotic homolog 2 Homo sapiens 131-135 22180888-1 2011 We applied infrared matrix isolation spectroscopy to investigate the reactions between Cl atom and acetylene (C2H2) in a para-hydrogen (p-H2) matrix at 3.2 K; Cl was produced via photodissociation at 365 nm of matrix-isolated Cl2 in situ. Hydrogen 126-134 polyhomeotic homolog 2 Homo sapiens 136-140 22068262-3 2012 The hydrogen consumption rates were affected by both P(H2) (hydrogen partial pressure) and mixing intensity. Hydrogen 4-12 polyhomeotic homolog 2 Homo sapiens 53-58 22068262-3 2012 The hydrogen consumption rates were affected by both P(H2) (hydrogen partial pressure) and mixing intensity. Hydrogen 60-68 polyhomeotic homolog 2 Homo sapiens 53-58 24382574-1 2014 The quantum solid para-hydrogen (p-H2) has emerged as a new host for matrix isolation experiments. Hydrogen 18-31 polyhomeotic homolog 2 Homo sapiens 33-37 24022263-1 2013 We use femtosecond optical Kerr effect (OKE) spectroscopy to perform time- and wavelength-resolved pump-probe measurements on the energetics and lifetimes of transverse optical phonons and J = 2 rotons in solid para-hydrogen (pH2). Hydrogen 216-224 polyhomeotic homolog 2 Homo sapiens 226-229 18712869-2 2008 The back conversion from para-hydrogen ( p-H 2) to ortho-hydrogen ( o-H 2) was followed by NMR by recording the increase in the intensity of the signal of o-H 2 at regular intervals of time. Hydrogen 25-38 polyhomeotic homolog 2 Homo sapiens 41-46 18712869-2 2008 The back conversion from para-hydrogen ( p-H 2) to ortho-hydrogen ( o-H 2) was followed by NMR by recording the increase in the intensity of the signal of o-H 2 at regular intervals of time. Hydrogen 30-38 polyhomeotic homolog 2 Homo sapiens 41-46 16422608-1 2006 The infrared spectrum of the complex between o-H2 and H2O, D2O, or HDO, isolated in a matrix of solid p-H2, has been studied between 20 and 4500 cm(-1). Hydrogen 47-49 polyhomeotic homolog 2 Homo sapiens 102-106 18218891-3 2008 We demonstrate techniques, using magnetic resonance imaging and para-hydrogen (p-H2) polarization, that allow direct visualization of gas-phase flow and the density of active catalyst in a packed-bed microreactor, as well as control over the dynamics of the polarized state in space and time to facilitate the study of subsequent reactions. Hydrogen 69-77 polyhomeotic homolog 2 Homo sapiens 79-83 16424336-1 2006 The quantum solid para-hydrogen (p-H2) has recently proven useful in matrix isolation spectroscopy. Hydrogen 18-31 polyhomeotic homolog 2 Homo sapiens 33-37 16201664-4 2005 Because the rate of hydrogen entering the iron lattice increases with PH2(1/2), and the rate of hydrogen production from corrosion, far from equilibrium conditions, is independent of PH2, at some time under closed system conditions the two rates become equal and a steady-state PH2 is attained. Hydrogen 20-28 polyhomeotic homolog 2 Homo sapiens 70-73 16201664-7 2005 A method is presented to calculate PH2 values along the flow direction in a PRB, and thus the maximum PH2 value that can possibly develop, assuming no bacterial utilization of the produced hydrogen. Hydrogen 189-197 polyhomeotic homolog 2 Homo sapiens 35-38 15836040-0 2005 The binding of 4He and 3He to a hydrogen molecule: a computational study for pH2 and oH2. Hydrogen 32-40 polyhomeotic homolog 2 Homo sapiens 77-80 15267283-5 2004 Since the calculated H2 cluster temperature (approximately 3.1 K) is below the superfluid transition temperature predicted for pH2 with density between 40% and 80% of the triple-point density, a shell-like region of low density near the cluster surface can be expected to be superfluid. Hydrogen 21-23 polyhomeotic homolog 2 Homo sapiens 127-130