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- Hypotheses in phase transition theories: “What is ‘liquid’?”Publication . Maguire, John F.; Woodcock, LeslieTheories predicting thermodynamic properties that describe liquid phase transitions and critical phenomena have resulted in the award of three Nobel prizes in physics: (i) “Continuity of Gaseous and Liquid States” hypothesis of van der Waals [1910], (ii) “Critical Point Universality” hypothesis embodied in the renormalization group (RG) theory of Wilson [1982], and (iii) “Topological Defect Melting” hypothesis that 2D-crystal-liquid states exhibit ‘hexatic’ phases in KTHNY theory [Kosterlitz et al. 2016]. All three hypotheses are invalidated by the reality of experimental results and raise a fundamental question first posed by Barker and Henderson in 1976: “What is liquid”. A single Gibbs phase, that includes triple-point (Tt) liquid, extends over the whole fluid density range to temperatures above the Boyle temperature (TB). Below TB, above the critical temperature Tc, predominantly gas- and liquid-like states are bounded by a narrow colloidal ‘supercritical mesophase’ with constant rigidity (ω = (dp/dρ)T). The liquid phase also becomes colloidal at the onset of pre-freezing growth and percolation of crystallites in a narrow density range below freezing density for all T > Tt. Whereas the Boyle line (RT = p/ρ) defines a crystalline ground state, a rigidity line, RT = ω, interpolates to an amorphous ground-state akin to random close packing (RCP) at T = 0. All states of gas, liquid, and crystals, are present in the stable ‘liquid phase’ and, are represented in thermodynamic p-T states all along the rigidity line. For 2D liquid–crystal coexistence in constrained computer models, the KTHNY theory describes a non-equilibrium fracture process. Hetero-phase fluctuations, leading to percolation transitions, have been misconstrued as “hexatic” in 2D, as also have 2-phase coexistence states, that are homogeneous in the absence of gravity.
- Disquisitions relating to principles of thermodynamic equilibrium in climate modellingPublication . Woodcock, LeslieWe revisit the fundamental principles of thermodynamic equilibrium in relation to heat transfer processes within the Earth’s atmosphere. A knowledge of equilibrium states at ambient temperatures (T) and pressures (p) and deviations for these p-T states due to various transport ‘forces’ and flux events give rise to gradients (dT/dz) and (dp/dz) of height z throughout the atmosphere. Fluctuations about these troposphere averages determine weather and climates. Concentric and time-span average values (z, Δt)) and its gradients known as the lapse rate = d < T(z) >/dz have hitherto been assumed in climate models to be determined by a closed, reversible, and adiabatic expansion process against the constant gravitational force of acceleration (g). Thermodynamics tells us nothing about the process mechanisms, but adiabatic-expansion hypothesis is deemed in climate computer models to be convection rather than conduction or radiation. This prevailing climate modelling hypothesis violates the 2nd law of thermodynamics. This idealized hypothetical process cannot be the causal explanation of the experimentally observed mean lapse rate (approx.−6.5 K/km) in the troposphere. Rather, the troposphere lapse rate is primarily determined by the radiation heat-transfer processes between black-body or IR emissivity and IR and sunlight absorption. When the effect of transducer gases (H2O and CO2) is added to the Earth’s emission radiation balance in a 1D-2level primitive model, a linear lapse rate is obtained. This rigorous result for a perturbing cooling effect of transducer (‘greenhouse’) gases on an otherwise sunlight-transducer gas-free troposphere has profound implications. One corollary is the conclusion that increasing the concentration of an existing weak transducer, i.e., CO2, could only have a net cooling effect, if any, on the concentric average (z = 0) at sea level and lower troposphere (z < 1 km). A more plausible explanation of global warming is the enthalpy emission ’footprint’ of all fuels, including nuclear.
- On the empirical determination of a gas-liquid supercritical mesophase and its phenomenological definitionPublication . Woodcock, LeslieWe respond to recent articles (Int. J. Thermophysics 39 139 2018, ibid.40 21 2019) that seek to deny the veracity of the empirical discovery and thermodynamic description of a gas-liquid supercritical mesophase. These IJT articles are misleading because they are based upon a false premise that the mesophase is a hypothetical concept. There is no "mesophase hypothesis" as wrongly stated in the title of article IJT, 40 21, 2019. Unlike the critical point continuity hypothesis of van der Waals (1873), or the universal critical point scaling hypothesis advocated by Anisimov and Sengers, and others since 1965, the supercritical mesophase is an empirical entity. If a hypothetical van der Waals fluid with the properties of a critical-state point with divergent isochoric heat capacity, and with the scaling properties of "universality" theory, were to exist, it could be used to vitiate the second law of thermodynamics. By contrast, the supercritical mesophase, discovered originally from computer experiments, is an empirically established equilibrium fluid region, of two-state systems of gas plus liquid, within a single Gibbs phase; the properties of which are determined by the laws of thermodynamics. Here, we provide a phenomenological definition of the gas-liquid supercritical mesophase that accords with the body of compelling experimental results over a 150-year period since van der Waals including modern computer experiments
- Intermolecular potential model Hamiltonians for Gas–Liquid coexistencePublication . Woodcock, LeslieA fundamental, hitherto unanswered, question in liquid-state physics is: "What is the minimum requirement of a molecular interaction Hamiltonian for the existence of a stable liquid that can coexist with its vapor phase?". It has been the subject of speculation in the thermophysical property literature since Hagen et al. (Nature 1993) reported ’no liquid phase’ in a computer site–site pairwise model Hamiltonian for C60. In more recent reports we have found that for simple fuids, with spherical, pairwise model Hamiltonians there exists a supercritical mesophase colloidal description of gas–liquid coexistence with a T-p density-surface critical divide being defned thermodynamically by the intersection of percolation loci. We have also reported compelling experimental evidence for the existence of a pre-freezing percolation transition whence hetero-phase fuctuations of micro-crystallites percolate equilibrium liquid state phase volume. These percolation phenomena can explain the apparent disappearance of the boiling line at fnite range of attraction. As the attractive range shortens, the interception of the percolation line that defne the critical-line between two-phase coexistence, and one-phase supercritical mesophase, shifts to lower T. It then intercepts with the pre-freezing percolation line, to trigger a triple point of gas, liquid and solid states, all at the same T,p-state hence also the same chemical potential. Consequently, all model pairwise classical molecular Hamiltonians with a fnite size, plus attractive term, however short-range, or however weak, exhibit a triple point with a liquid–vapor coexisting state at a sufcient low temperature.
- On the thermodynamics of aluminum cladding oxidation: water as the catalyst for spontaneous combustionPublication . Maguire, John F.; Woodcock, LeslieA recent article (Casey et al. in J Failure Anal Prev 22:1252–1259, 2022) finds a thermodynamic explanation for the catastrophic effect of water as an extinguisher in aluminum-clad tower block fires (Entropy 22: 14, 2020) to be ‘‘unsubstantiated hypotheses’’ and ‘‘suppositions unsupported by data’’. The article by Casey et al., however, is misleading because it is based upon a false premise that it is the hydrolysis of solid aluminum panels that produce hydrogen (H2), which was not detected in their experiments. The combustion of aluminum (Al) to alumina (Al2O3) reaction is highly exothermic to the extent that it can be explosive, but the reaction is inhibited, for all temperatures of solid and liquid Al, below the melting point of alumina (2250 C), by the formation of a thin nanometre skin of alumina that prevents combustion. In tower block infernos of Al-plastic cladding materials, there cannot be production of detectable hydrogen gas, as wrongly assumed by Casey et al., who only investigate the laboratory hydrolysis reaction of solid aluminum in cladding samples, and not the combustion conditions at temperatures exceeding 1500 C. Here we show that H2 is an intermediate in the Al-combustion mechanism of cladding fires, and that water (H2O) is the catalyst. This is one of two possible reaction mechanisms that enable combustion by circumventing direct oxidation of Al. For cladding with adjacent plastic insulation material, water provides an alternative mechanism via methane and the carbide Al4C3 as intermediates, also with H2O as the catalyst.
- Supercritical fluid gaseous and liquid states: a review of experimental resultsPublication . Khmelinskii, Igor; Woodcock, LeslieWe review the experimental evidence, from both historic and modern literature of thermodynamic properties, for the non-existence of a critical-point singularity on Gibbs density surface, for the existence of a critical density hiatus line between 2-phase coexistence, for a supercritical mesophase with the colloidal characteristics of a one-component 2-state phase, and for the percolation loci that bound the existence of gaseous and liquid states. An absence of any critical-point singularity is supported by an overwhelming body of experimental evidence dating back to the original pressure-volume-temperature (p-V-T) equation-of-state measurements of CO2 by Andrews in 1863, and extending to the present NIST-2019 Thermo-physical Properties data bank of more than 200 fluids. Historic heat capacity measurements in the 1960s that gave rise to the concept of “universality” are revisited. The only experimental evidence cited by the original protagonists of the van der Waals hypothesis, and universality theorists, is a misinterpretation of the isochoric heat capacity Cv. We conclude that the body of extensive scientific experimental evidence has never supported the Andrews–van der Waals theory of continuity of liquid and gas, or the existence of a singular critical point with universal scaling properties. All available thermodynamic experimental data, including modern computer experiments, are compatible with a critical divide at Tc, defined by the intersection of two percolation loci at gaseous and liquid phase bounds, and the existence of a colloid-like supercritical mesophase comprising both gaseous and liquid states.
- Global warming by geothermal heat from fracking: energy industry’s enthalpy footprintsPublication . Woodcock, LeslieHypothetical dry adiabatic lapse rate (DALR) air expansion processes in atmosphere climate models that predict global warming cannot be the causal explanation of the experimentally observed mean lapse rate (approx.−6.5 K/km) in the troposphere. The DALR hypothesis violates the 2nd law of thermodynamics. A corollary of the heat balance revision of climate model predictions is that increasing the atmospheric concentration of a weak molecular transducer, CO2 , could only have a net cooling effect, if any, on the biosphere interface temperatures between the lithosphere and atmosphere. The greenhouse-gas hypothesis, moreover, does not withstand scientific scrutiny against the experimental data. The global map of temperature difference contours is heterogeneous with various hotspots localized within specific land areas. There are regional patches of significant increases in time-average temperature differences, (∆) = 3 K+, in a ring around the arctic circle, with similar hotspots in Brazil, South Africa and Madagascar, a 2–3 K band across central Australia, SE Europe centred in Poland, southern China and the Philippines. These global-warming map hotspots coincide with the locations of the most intensive fracking operational regions of the shale gas industry. Regional global warming is caused by an increase in geothermal conductivity following hydraulic fracture operations. The mean lapse rate (d/dz)z at the surface of the lithosphere will decrease slightly in the regions where these operations have enhanced heat transfer. Geothermal heat from induced seismic activity has caused an irreversible increase in enthalpy (H) input into the overall energy balance at these locations. Investigating global warming further, we report the energy industry’s enthalpy outputs from the heat generated by all fuel consumption. We also calculate a global electricity usage enthalpy output. The global warming index, <∆T-biosphere> since 1950, presently +0.875 K, first became non-zero in the early 1970’s around the same time as natural gas usage began and has increased linearly by 0.0175 K/year ever since. Le Chatelier’s principle, applied to the dissipation processes of the biosphere’s ∆H-contours and [CO2 ] concentrations, helps to explain the global warming statistics.
- Science in the times of Covid. An alternative hypothesisPublication . Stallinga, Peter; Khmelinskii, Igor; Woodcock, LeslieScience consists of testing hypothesis. However, this Scientific Method is used ever more scarcely, and is replaced by general research to help making society a better place. In the current work we analyze how the approach of a solution to the sanitary problem caused by the SARS-CoV-2 virus has been done in a non-scientific way leading to erroneous conclusions. Moreover, we form an alternative hypothesis that has withstood our own attempts at debunking. We conclude that the pandemic is caused by misdiagnosis of other respiratory illnesses and a runaway-testing-scenario.