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Phase transition luminescence in boiling water; Evidence for clusters
Abstract
Emission spectrography shows an anomalous increase in the infrared radiation from boiling water. Emission bands are seen at 2.10μ and 1.54μ wavelengths. Their strength depends on the rate of liquid vapour phase transition. They do not appear in water superheated to 110°C at one atmosphere. The bands, of the order of 100 cm−1 wide, are not in the water vapor spectrum.These data lie outside the range of phenomena on which our present views of water are based and appear to provide evidence for the existence of clusters of molecules in liquid water.
... The experiments [ 33 ] were carried out in the installation including a vessel with boiling water, a cooled glass surface for the vapor condensation, and a sensitive system of the infrared radiation recording. There was observed an anomalous increase in the infrared radiation intensity from the boundary of glass surface, i.e. from the condensed vapor. ...
... In [ 33 ] the positions of all from four peaks correspond to emitted energy that exceeds the phase transition one. The peaks of radiation on 1.5 mcm, 2.1 mcm and, apparently, on 2.5 mcm and 3.2 mcm, with taking into account the relation (4.4), can be attributed to condensation of water's dimers and higher molecular complexes with n = 2 and m = 4, 3, 2. ...
... 8. In [ 33 ] the recorded energy could be estimated as 3 -5% of full phase transition energy. The problem of characteristic radiation yield has not been solved yet in the frame of offered theory. ...
Crystallization and vapor condensation are considered as the processes of sequential penetration of single atoms/molecules into condensate. In
the course of these transitions the transitive radiation must be generated, which would carry away the liberated latent heat by photons of characteristic
frequencies. The transient radiation is examined by the general Ginzburg–Frank theory. The emission of defined frequencies determined
by the values of liberated latent heat is confirmed by analyses of several experiments of authors and other researchers.
... Potter and Hoffman [32] carried out experiments in a glass vessel with boiling water and used a sensitive recording system for infrared radiation. An anomalous increase in infrared radiation intensity from the boundary between the glass surface and the condensed vapour was observed. ...
... 2) For higher cloud densities, values of ε > 1.0 were observed similar to those of the "phase transition luminescence" described in the paper [32] and were attributed to water clusters containing c = 11 and c = 17 molecules per cluster. ...
... Carlon used the cluster idea but insisted that his observations revealed at least three aspects of investigated phenomena that had not been reported in [32]. They are listed below. ...
This paper presents new experimental evidence of the PeTa effect—infrared characteristic radiation under first order phase transitions, especially the crystallization of melts and the deposition and condensation of vapours/gases. The PeTa effect describes the transient radiation that a particle (i.e., atom, molecule or/and cluster) emits during a transition from a meta-stable higher energetic level (in a super-cooled melt or a super-saturated vapour) to the stable condensed lower level (in a crystal or a liquid). The radiation removes latent heat with photons of characteristic frequencies that are generated under this transition. The abbreviation “PeTa effect” means Perel’man-Tatartchenko’s effect.
... In Ref. [6], experiments were carried out in an installation including a vessel with boiling water, a cooled glass surface for the vapor condensation, and a sensitive system of the infrared radiation recording. The authors of Ref. [6] observed an anomalous increase in the infrared radiation intensity from the boundary to the glass surfacecondensed vapor. ...
... In Ref. [6], experiments were carried out in an installation including a vessel with boiling water, a cooled glass surface for the vapor condensation, and a sensitive system of the infrared radiation recording. The authors of Ref. [6] observed an anomalous increase in the infrared radiation intensity from the boundary to the glass surfacecondensed vapor. The intensity was increased with the condensation rate increasing. ...
... In Ref. [5], near l 1w range radiation was recorded. In Ref. [6], the positions of both peaks correspond to emitted energy that exceeds the phase-transition energy. These results could be explained, firstly, by higher harmonics radiation with respect to formula (1) and, secondly, by the particular conditions of the water vapor condensation in Ref. [6]. ...
The paper presents evidence of the existence of infrared characteristic radiation accompanying phase transitions of the first order, especially crystallization. Experimental results of the author and other researchers concerning crystallization from the melt of some infrared transparent substances (alkali halides, sapphire) and non-transparent ones (tellurium, ice, copper) are presented, as well as condensation of water vapor. The author has critically analyzed these experimental data in terms of correspondence to the theoretical models. The last ones are based on the assumption that the particle, during transition from higher energetic level (vapor or melt) to the lower energetic level (crystal), emits one or more photons equal to the latent energy of the transition, or part of the energy. Based on the experimental data, the author proposes a model explaining the appearance of a window of transparency for the characteristic radiation in the substances when first-order phase transitions take place. It is possible to imagine several applications of this phenomenon in different fields. For instance, new types of crystallization process regulation, crystallization stimulated by the characteristic radiation, an infrared laser based on the condensation of water vapor, or crystallization of lithium fluoride or sapphire. Formation of hailstorm clouds in the atmosphere should be accompanied by intensive characteristic infrared radiation that could be detected for process characterization and meteorological warnings.
... In [19] experiments were carried out in an apparatus comprising a vessel with boiling water, a cooled glass surface for vapor condensation, and a sensitive recording system for infrared radiation. An anomalous reinforcement of infrared radiation from the boundary between the glass surface and condensed vapor was observed. ...
... Relative intensity of IR radiation I/I bb (I bb is intensity of black body IR radiation for the same temperature) recorded under water vapor condensation. A: from [19] vs wavelength λ. B: from [21] for λ = 10µm vs cloud temperature Ѳ and droplet "CL", g/m 2 -product of droplet mass concentration C g/m3, and optical path length L, 3.05 m; lower curve shows emissivity calculated for cloud from simple model. ...
This paper considers the infrared characteristic radiation (IRCR) during the first order phase transitions (crystallization, condensation and sublimation) of water. Experimental results are analyzed in terms of their correspondence to the theoretical model. This model is based on the assertion that the particle's (atom, molecule, or cluster) transition from the higher energetic level in a meta-stable phase (vapor or liquid) to a lower level in a stable phase (liquid or crystal) emits one or more photons. The energy of these photons depends on the latent energy of the phase transition and the character of bonds formed by the particle in the new phase. For all investigated substances, this energy falls in the infrared range. Many sources of the infrared radiation recorded in the atmosphere seem to be a result of crystallization, condensation and sublimation of water during fog and cloud formation. The effect under investigation must play a very important role in atmospheric phenomena: it is one of the sources of Earth's cooling; formation of hailstorm clouds is accompanied by intensive characteristic infrared radiation that could be used for process characterization and meteorological warnings. IRCR seems to be used for atmospheric energy accumulation. Thus, IRCR, together with wind, falling water, solar and geothermal energies, makes available the fifth source of ecologically pure energy.
... 3.3. Work [31] reports the appearance of emission lines of 0.1 μm in width near 2.10 and 1.54 μm during water vapor condensation. The intensities of the lines were 100 and 200 times higher than the background ones. ...
... ~ 57.8, and ~ 79 μm. Taking into account Eq. (4), the radiation maxima at 2.10 and 1.54 μm from [31] correspond to twoophoton radiation during water vapor condensation with the pree liminary formation of dimers and higher order molecular complexes: ~ 2.10 and ~ 1.54 μm. Thus, we have presented our interpretation of the experimental results concerning the recording of IR ...
It is shown that the nature of some IR sources in the Earth’s atmosphere is based on the characteristic IR radiation (IRCR) of the first order phase transitions (water condensation and crystallization).
Experimental and theoretical evidence of the existence of IRCR are discussed. The theory of the phenomenon is based on the statement that a particle (atom, molecule, or cluster) emits one or a few photons while transiting from a higher meta-stable energetic level (vapor or liquid) to a lower one (liquid or crystal); the energy of these photons is connected in some way with the latent energy of the phase transition. The effect under study plays a very important role in atmospheric phenomena: it is one of the sources of the cooling of the Earth; the formation of clouds, especially storm ones, is accompanied by intensive IRCR, which could be detected for process characterization and storm warnings. The effect can be used for energy accumulation in the atmosphere. The IRCR might explain the red color and infrared emission of Jupiter.
... Starting in the late 1960 s researchers began reporting evidence of phase transition radiation for vapor-liquid, liquid-solid, and vapor-solid transitions. In 1968, Potter and Hoffman [8] reported an abnormal increase of infrared radiation from boiling water at 1.54 lm and 2.10 lm. The authors referred to this phenomenon as phase transition luminescence and asserted that water clusters were responsible for radiating latent heat during the boiling process. ...
... Initial attempts at simulation were made using the same CCN number density as the previous 60 C case, 3.8 Â 10 4 cm À3 , with temperature dependence included only through the terms noted above in Eq. (8). This approach, however, was not able to adequately match the experimental data. ...
Infrared radiation associated with vapor-liquid phase transition of water is investigated using a suspension of cloud droplets and mid-IR (3-5 µm) radiation absorption measurements. Recent measurements and Monte Carlo modeling performed at 60°C and 1 atm resulted in an interfacial radiative phase-transition probability of 5E-8 and a corresponding surface absorption efficiency of 3 to 4%, depending on wavelength. In this paper the measurements and modeling have been extended to 75°C in order to examine the effect of temperature on water's liquid-vapor phase-change radiation. It was found that the temperature dependence of the previously proposed phase-change absorption theoretical framework by itself was insufficient to account for observed changes in radiation absorption without a change in cloud droplet number density. Therefore the results suggest a strong temperature dependence of cloud condensation nuclei (CCN) concentration, i.e., CCN increasing approximately a factor of two from 60°C to 75°C at near saturation conditions. The new radiative phase-transition probability is decreased slightly to 3E-8. Theoretical results were also calculated at 50°C in an effort to understand behavior at conditions closer to atmospheric. The results suggest that accounting for multiple interface interactions within a single droplet at wavelengths in atmospheric windows (where anomalous IR radiation is often reported) will be important. Modeling also suggests that phase-change radiation will be most important at wavelengths of low volumetric absorption, i.e., atmospheric windows such as 3-5 µm and 8-10 µm, and for water droplets smaller than stable cloud droplet sizes (< 20 µm diameter), where surface effects become relatively more important. This could include unactivated, hygroscopic aerosol particles (not CCN) that have absorbed water and are undergoing dynamic evaporation and condensation. This mechanism may be partly responsible for water vapor's IR continuum absorption in these atmospheric windows.
... Unfortunately, we could not obtain high quality pictures to reproduce here. Potter and Hoffman (1968) describe experiments that were carried out in an apparatus comprising a vessel with boiling water, a cooled glass surface for vapor condensation, and a sensitive recording system for infrared radiation. An anomalous increase in infrared radiation intensity from the boundary between the glass surface and condensed vapor was observed. ...
... The radiation peaks at ∼ 3.2 µm, 2.10 µm and 1.54 µm from Potter and Hoffman (1968) experiments as well as 1.05 µm and ∼0.9 µm from Ayad (1971) experiments, when taking into account the relation (4), can be attributed to the emission of two photon radiation during condensation of water dimmers and higher molecular complexes: λ 2 (C,2) ∼ 3.2 µm, λ 2 (C,3) ∼ 2.10 µm, λ 2 (C,4) ∼ 1.54 µm, λ 2 (C,6) ∼ 1.05 µm, λ 2 (C,7) ∼ 0.9 µm. It has to be mentioned that in experiments by Potter and Hoffman (1968), the condensed water forms a thin film on the glass surface. The water molecules have more adhesion to the glass surface than to each other, and as a result of this, the lower energetic level of phase transition is located deeper than the level in larger volumes of water. ...
This paper presents new experimental evidence of the PeTa effect—infrared characteristic radiation under first order phase transitions, especially the crystallization of melts and the deposition and condensation of vapours/gases. The PeTa effect describes the transient radiation that a particle (i.e., atom, molecule or/and cluster) emits transient radiation during a transition from a meta-stable higher energetic level (in a super-cooled melt or a super-saturated vapour) to the stable condensed lower level (in a crystal or a liquid). The radiation removes latent heat with photons of characteristic frequencies that are generated under this transition. The abbreviation “PeTa effect” means Perel’man-Tatartchenko’s effect.
... These sources were the bottom sides of cumulus clouds and the rising warm air saturated with water vapor. The authors of [9] observed an anomalous increase in the infrared radiation intensity from the boundary the glass surfacecondensed vapor. In the range 1-4 mm, the integral intensity was found to be four times more than Plank's radiation. ...
... The intensity of both bands exceeded the background radiation by a factor of ten. Probably, a third band with a wavelength of 3.2 mm, not mentioned by the authors, could be detected on the curve from [9]. ...
The paper discusses a possibility of new effects in quantum electronics: amplification of certain frequency infrared beams in supersaturated vapors or super-cooled melts as well as design of infrared lasers based on a new type of pumping. The basis of these effects is the existence of characteristic infrared radiation accompanying phase transitions of the first order, especially crystallization and condensation. Experimental results of the author and other researchers concerning characteristic infrared emission detection during crystallization from the melt of some substances (alkali halides, sapphire, tellurium, ice, etc.) are presented, as well as condensation of water vapor. The author has critically analyzed these experimental data in terms of correspondence to the theoretical models. The last ones are based on the assumption that the particle (atom, molecule or cluster), during transition from higher energetic level (vapor or melt) to the lower energetic level (crystal), emits one or more photons depending on the latent energy of the transition. Based on the experimental data, the author postulates a transparency window appearance for the characteristic radiation in the substances where first-order phase transitions take place.
... Unfortunately, we could not obtain high quality pictures to reproduce here. Potter and Hoffman (1968) describe experiments that were carried out in an apparatus comprising a vessel with boiling water, a cooled glass surface for vapor condensation, and a sensitive recording system for infrared radiation. An anomalous increase in infrared radiation intensity from the boundary between the glass surface and condensed vapor was observed. ...
... The radiation peaks at ∼ 3.2 µm, 2.10 µm and 1.54 µm from Potter and Hoffman (1968) experiments as well as 1.05 µm and ∼0.9 µm from Ayad (1971) experiments, when taking into account the relation (4), can be attributed to the emission of two photon radiation during condensation of water dimmers and higher molecular complexes: λ 2 (C,2) ∼ 3.2 µm, λ 2 (C,3) ∼ 2.10 µm, λ 2 (C,4) ∼ 1.54 µm, λ 2 (C,6) ∼ 1.05 µm, λ 2 (C,7) ∼ 0.9 µm. It has to be mentioned that in experiments by Potter and Hoffman (1968), the condensed water forms a thin film on the glass surface. The water molecules have more adhesion to the glass surface than to each other, and as a result of this, the lower energetic level of phase transition is located deeper than the level in larger volumes of water. ...
This paper considers the emission of infrared characteristic radiation during the first order phase transitions of water (condensation and crystallization). Experimental results are analyzed in terms of their correspondence to the theoretical models. These models are based on the assumption that the particle's (atom, molecule, or cluster) transition from the higher energetic level (vapor or liquid) to a lower one (liquid or crystal) produces an emission of one or more photons. The energy of these photons depends on the latent energy of the phase transition and the character of bonds formed by the particle in the new phase. Based on experimental data, the author proposes a model explaining the appearance of a window of transparency for the characteristic radiation in the substances when first order phase transitions take place. The effect under investigation must play a very important role in atmospheric phenomena: it is one of the sources of Earth's cooling; formation of hailstorm clouds in the atmosphere is accompanied by intensive characteristic infrared radiation that could be detected for process characterization and meteorological warnings. The effect can be used for atmospheric heat accumulation. Together with the energy of wind, falling water, and solar energy, fog and cloud formation could give us a forth source of ecologically pure energy. Searching for the presence of water in the atmospheres of other planets might also be possible using this technique. Furthermore, this radiation might explain the red color and infrared emission of Jupiter.
... It was shown in the early papers [35][36][37] that first order phase transitions such as condensation of water vapor are accompanied by characteristic infrared radiation. This phenomenon, sometimes called the PeTa effect (this abbreviation means Perel'man-Tatarchenko's effect), is really important for remote sensing of the cloudy atmosphere [38][39][40] . ...
Infrared irradiation of a droplet cluster has been used during several years as the main method of preventing coalescence of the cluster with a layer of water. The desired effect is achieved by suppressing the condensational growth of large droplets. In new experiments, it was first discovered that prolonged exposure to infrared radiation leads to asymptotic equalization of radii of various droplets. A theoretical analysis of the experimental results was carried out on the basis of the developed model for transient heat transfer. The suggested model includes the thermal effect of infrared radiation, the dynamics of the combined process of evaporation and condensation, as well as convective heat transfer with the surrounding humid air. When calculating the infrared heating of semi-transparent water droplets, the spectral composition of the external radiation is taken into account. The evaporation and condensation of water droplets is considered taking into account the kinetics of the process in the Knudsen layer and the vapor diffusion in the outer part of the boundary layer. Simple analytical relations are obtained for the asymptotic equilibrium parameters of small droplets. The numerical data for the time variation in the size of cluster droplets streamlined by a mixture of air and supersaturated water vapor are in good agreement with the results of laboratory measurements.
... In 1968, two scientists Potter W R, Hoffman J G, pioneeringly found that vapor condensation can radiate infrared (IR). The paper [1] of findings was published in the volume 8 of Infrared Physics Journal of that year. Until now lots of experiments by different scientists in different laboratories have verified the same fact of IR emission induced by phase change. ...
... These sources were the bottom sides of cumulus clouds with a temperature of - 5℃ and the rising warm air saturated with water vapor. In [10], Potter and Hoffman describe the anomalous phenomenon as phase-transition luminescence to address the intensity increase in an apparatus comprising a vessel with boiling water. Their research suggests that the integrated intensity was four times higher than Plank's radiation in the range of 1- 4μm.Two main emission bands were set in the range of 2.10μm and 1.54μm.Compared with the background radiation, it is easy to find that the intensity of both bands exceeded by a factor of ten. ...
The paper considers the infrared characteristic radiation (IRCR) during the first order phase transitions (crystallization, condensation and sublimation) of water. The experimental results show that when the particles (atoms, molecules, clusters) transfer from a higher energetic level to a lower level, partly of the latent heat will be liberation as the photon. By analyzing and summing up of a large number of references, in this paper, the radiative transfer mechanism is given and the radiative transfer equation is shown correspondingly. Besides, this paper also discusses the experiment of the phase change of water vapor condensation. IRCR can be used to solve some climate problems as well as the energy problem. The purpose of the paper is to have a study of the phase transition process, which will be helpful to us to have a further research about the cloud infrared laser that will contribute to search a forth source of ecologically pure energy by make full use of the energy in the clouds.
Removal of the latent heat at vapor condensation and/or crystallization (with temperature T << Tc) occurs, as is shown by theoretical calculations and the resulted experimental data, on characteristic frequencies and their higher harmonics'. Intensity of this radiation can be very high and can explain, in particular, the bright flashes at the phenomenon of sonoluminescence. Under the general laws of the quantum theory these processes can be stimulated by resonant frequencies, therefore it is possible to carry out the laser on such "condensation" radiation. Potential capacity and, in principle, simplicity of such devices should attract to them attention of researchers. Spectral features of atmospheric clouds correspond to characteristic frequencies of water vapor condensation and of CO2, CH4 condensation, etc. Radiative stimulation of their phase transitions can lead to control of atmospheric processes and of heat fluxes from the Earth, to regularization of its thermal regime.
Infrared radiation associated with vapor-liquid phase transition of water is investigated using a suspension of cloud droplets and mid-infrared (IR) (3-5 mu m) radiation absorption measurements. Recent measurements and Monte Carlo (MC) modeling performed at 60 degrees C and 1 atm resulted in an interfacial radiative phase-transition probability of 5 x 10(-8) and a corresponding surface absorption efficiency of 3-4%, depending on wavelength. In this paper, the measurements and modeling have been extended to 75 degrees C in order to examine the effect of temperature on water's liquid-vapor phase-change radiation. It was found that the temperature dependence of the previously proposed phase-change absorption theoretical framework by itself was insufficient to account for observed changes in radiation absorption without a change in cloud droplet number density. Therefore, the results suggest a strong temperature dependence of cloud condensation nuclei (CCN) concentration, i.e., CCN increasing approximately a factor of two from 60 degrees C to 75 degrees C at near saturation conditions. The new radiative phase-transition probability is decreased slightly to 3 x 10(-8). Theoretical results were also calculated at 50 degrees C in an effort to understand behavior at conditions closer to atmospheric. The results suggest that accounting for multiple interface interactions within a single droplet at wavelengths in atmospheric windows (where anomalous IR radiation is often reported) will be important. Modeling also suggests that phase-change radiation will be most important at wavelengths of low volumetric absorption, i.e., atmospheric windows such as 3-5 mu m and 8-10 mu m, and for water droplets smaller than stable cloud droplet sizes (<20 mu m diameter), where surface effects become relatively more important. This could include unactivated, hygroscopic aerosol particles (not CCN) that have absorbed water and are undergoing dynamic evaporation and condensation. This mechanism may be partly responsible for water vapor's IR continuum absorption in these atmospheric windows.
This paper considers a new physical phenomenon - infrared characteristic radiation (IRCR) at first order phase transitions (melt crystallization, and vapor condensation and/or deposition). Experimental results are analyzed in terms of their correspondence to the theoretical model. This model is based on the assertion that the particle’s (atom’s, molecule’s, or cluster’s) transition from a higher energetic level in a meta-stable or unstable phase (vapor or liquid) to a lower level in a stable phase (liquid or crystal) can emit one or more photons. The energy of these photons depends on the latent energy of the phase transition and the character of bonds formed by the particles in the new phase. For all investigated substances, this energy falls in the infrared range. This is a reason why the radiation is named as IRCR–infrared characteristic radiation. Many sources of the infrared radiation recorded in the atmosphere seem to be a result of crystallization, condensation and/or sublimation of water during fog and cloud formation. Thus, the effect under investigation must play a very important role in atmospheric phenomena: it is one of the sources of Earth’s cooling; formation of hailstorm clouds is accompanied by intensive characteristic infrared radiation that could be used for process characterization and meteorological warnings. IRCR seems to explain red color of Jupiter. It can be used for atmospheric energy accumulation, and, thus, together with wind, falling water, solar and geothermal energies, IRCR makes available the fifth source of ecologically pure energy.
Keywords: crystal growth from melt, crystal growth from vapor, vapor Trouton’s rule, atmospheric energy accumulation
PACS: 92.70.Cp, 78.30.Er DOI: 10.7498/aps.62.079203
Phase-change radiation is studied in water clouds undergoing liquid vapor phase transitions. Radiant energy transmission in the midinfrared (3.1-4.95 mu m) spectrum is measured in vapor liquid mixtures of water at 1 atm and 60 degrees C. Monte Carlo analysis of radiative heat transfer is performed to assess the contribution of infrared absorption associated with evaporative phase transition, for which a theoretical description is developed. The probability of absorptive, phase-change radiative relaxation is found to be on the order of 5 x 10(-8) per collision between a water vapor molecule and a liquid water droplet, which leads to a surface absorption efficiency of order 0.02 to 0.06 in the 3.1-4.95 mu m spectrum. Thereby, absorption of midinfrared radiation is slightly enhanced by evaporative absorption in water clouds.
This paper is the third one from the series of papers with the same titles published in this journal. The papers consider the infrared characteristic radiation (IRCR) during the first order phase transitions of water: crystallization, water vapor condensation, and water vapor deposition. Experimental results are analyzed in terms of their correspondence to the theoretical model. This model is based on the assertion that the particle's (atom, molecule, or cluster) transition from the higher energetic level in a metastable phase (vapor or liquid) to a lower level in a stable phase (liquid or crystal) produces an emission of one or more photons. The energy of these photons depends on the latent energy of the phase transition and the character of bonds formed by the particle in the new phase. For all investigated substances, this energy falls in the infrared range. Recorded in the atmosphere, numerous sources of the infrared radiation seem to be a result of crystallization, condensation and deposition of water during fog and cloud formation. The effect under investigation must play a very important role in atmospheric phenomena: it is one of the sources of Earth's cooling; formation of hailstorm clouds is accompanied by intensive IRCR that could be detected for process characterization and meteorological warnings. IRCR seems to be used for atmospheric energy accumulation and together with the wind, falling water, solar and geothermal energies makes available the fifth source of ecologically pure energy.
The paper presents evidence of the existence of infrared characteristic radiation ac-companying phase transitions of the first order, especially crystallization. Experimental results of the author and other researchers concerning crystallization from the melt of some infrared trans-parent substances (alkali halides, sapphire) and nontransparent ones (tellurium, ice, copper) as well as condensation of water vapor, are presented. The author has critically analyzed these ex-perimental data in terms of correspondence to theoretical models. The last ones are based on the assumption that a particle, during transition from a higher energetic level (vapor or melt) to the lower energetic level (crystal), emits one or more photons equal to the latent energy of the transi-tion, or part of the energy. Based on the experimental data, the author proposes a model explain-ing the appearance of a window of transparency for the characteristic radiation in the substances when first order phase transitions take place. It is possible to imagine several applications of this phenomenon in different fields, for instance, new types of crystallization process regulation; crys-tallization stimulated by the characteristic radiation; an infra-red laser based on the condensation of water vapor, or crystallization of lithium fluoride or sapphire. Formation of hailstorm clouds in the atmosphere should be accompanied by intensive characteristic infrared radiation that could be detected for process characterization and meteorological warnings. Detection of water in the at-mospheres of other planets can also be realized by this technique. This radiation might explain the red color of Jupiter as well as the orange color of its satellite Io.
It was shown that, under certain conditions, the growth of a new phase becomes much like a cooperative optical phenomenon
during which the heat of phase transition evolves as a sequence of superradiance pulses (phase-transition radiation). The
optical control of new-phase growth and the effect of optical properties of substances on the kinetics of phase transitions
are considered.
The ability of water to form molecular aggregates or clusters by hydrogen bonding is believed to be responsible for its unexplained spectral emission and absorption in many wavelength regions including the infrared. Data from 442 spectroradiometer observations of steam clouds and warm water fogs in the 7–13 μm infrared atmospheric ‘window’ region are summarized, and evidence is presented for cluster activity in the vapor phase. Observations show agreement with theory relating infrared absorption and emission to intermolecular vibrations in distributions of water ion clusters with mean sizes of 10–13 molecules per cluster. Clusters are implicated not only in infrared ‘continuum’ absorption of water vapor in the atmosphere, but in ionic activity affecting seemingly diverse phenomena such as cloud nucleation and the electrical conductivity of moist air.
Energy release by radiative relaxation during water vapor condensation is considered to be responsible for phase-transition radiation in the water vapor condensation process. A two-level transition model is proposed to explain the radiative transfer mechanism for condensation radiation of water vapor. The absorption coefficient due to condensation radiation and the associated optical properties are defined in the radiative transfer equation. The spectral profile of the source function of vapor condensation radiation is examined and agreement with the experimental characteristic wavelength of condensation radiation is found.
Es wird eine Näherungsmethode angegeben, aus den Ultrarotspektren den Anteil der freien nicht durch Wasserstoffbrücken gebundenen OH-Gruppen im flüssigen Wasser zu bestimmen. Die so erhaltenen Werte stehen in guter Übereinstimmung mit den aus DK-Messungen gefolgerten Anteilen. Dieses Näherrungsverfahren verdient daher als Diskussionsgrundlage einige Beachtung.An approximation method for the determination of the fraction of free, i.e. not hydrogen-bonded, OH-groups in liquid water from infrared spectra is described. The values obtained agree well with the fractions deduced from measurements of dielectric constants. This approximation method therefore deserves some attention as a basis for discussion.
An ƒ/2.5 spectral radiometer, consisting of telescope and monochromator mounted on a movable head, is described. By comparison with a blackbody standard and appropriate calibration, spectral radiances can be obtained in watts/cm2-micron-steradian. Observation on many targets indicates a nearly identical radiance for all. Space scans at a given wavelength do give target distinguishability however, and a discussion of possible cause is given. Rapid variations in radiance have been observed, and are still being investigated.
Spectral emissivities of water vapor were measured in the 2.7-µ region, at temperatures up to 1273°K. The measurements were used to calculate spectral and integrated infrared radiance of hot water vapor for several cases of interest. The spectrum of hot H2O is relatively poor in strong "hot" bands, in contrast to the case of CO2. The general character of the rotational structure in the spectrum of the hot gas is similar to the case of room temperature, although some additional lines are observed at high temperatures. Consequently, care must be taken in selecting the spectral intervals over which radiance integrals are to be calculated.
Two types of theoretical models for an absorption band are described and applied to infrared absorption bands of CO2 and H2O. For Co2, which has a regular fine structure the so-called Elasser model, which assumes eqally-spaced, equally-intense lines, can be applied. For H2O, which has a highly irregular fine structure, the so-called statistical or Goody model, which assumes random spacings and intensity distribution, is applicable. The individual lines are assumed to have the Lorentz shape in both models. The method of application of these models to the experimentally observed bands is discussed in detail.
Water vapor error function absorption coefficients for visible and near ir radiation have been recalculated from experimental transmission data. The error function absorption coefficients and the resulting transmissions as a function of precipitable water vapor are tabulated for wavelengths from 0.2 micro to 1.3 micro. Comparisons are made between computed and measured spectral transmittances.
The spectral transmission of carbon monoxide, nitrous oxide, and mixtures of the two has been studied in the 2200-cm(-1) region, where overlapping absorption bands occur. With spectral slit widths sufficiently large to include several absorption lines, it was found that the observed spectral transmittance of a mixture is equal to the product of the transmittances of the components measured separately, provided that sufficient nitrogen is added to give the same total pressure for all samples. This result was also obtained for overlapping bands of nitrous oxide and methane in the 1300-cm(-1) region. The present work confirms Burch's earlier studies of overlapping bands of CO(2) and water vapor. An investigation of the possible breakdown of the multiplicative property of transmission for narrow spectral slit widths was inconclusive.