Electronic Energy Explosion (EEE) in Air
is connected with nitrogen oxidation branched chain reaction [1]. Тhe
term EEE was used in [1] because of observation of avalanche-like growth
of excited molecules and free charges concentrations in our system. It
is well known that NO formation from nitrogen and oxygen is an
endothermic process [2].
The needed energy for NO formation is given by electric discharge. Further NO transformations proceed with energy release [3].
If
the reaction would finish at this stage the whole process together with
initiating discharge would lead to release of approximately 7
kcal/mole. But the expected continuation of the reaction connected with
equilibrium establishing between dimers and monomers of NO2
concentrations needs energy. The decay of dimer to two NO2 molecules
proceeds with energy consumption:
Thus
the entire energy balance is negative (it needs about 6 kcal/mole). The
energy needed for the reaction (4) is to be got from gaseous mixture.
In this case the gas temperature will diminish. From cooling of air to
100 degrees it is possible to obtain only (5/2)*2[cаl/
(mole*Kelvin)]*100(Kelvin) = 500 cаl/mole. It follows from this that the
equilibrium establishing dimers monomers will happen at some
temperature lower than the initial T, and the percentage of monomers
will be small. At low temperature a rise of luminescence intensity can
be expected resulting from the contribution of N2O3 molecules [4,5].
NTC
should be expected for the rate of nitrogen oxidation chain reaction,
as it follows from results of [6,7]: it was shown in [6] that chain
branching in this reaction can be described by the equation:
Where k is the rate constant for the recombination process O + NO + M => NO2* + M.
NTC was observed for this rate constant in [7].
In
accordance with mentioned above data we have found that super
luminescence from EEE initiated by electrical discharge near the ferrite
surface can be observed only at lower (relative to room temperature)
temperatures. The super luminescence was not observed at 25o C. The
cooling of electrodes to 0o C at the temperature 25o C of surrounding
air resulted in arising bright blue super luminescence analogical to
radiation described in [8]. This result indicates on the existence of
some "super luminescence limit" of a nitrogen oxidation branched chain
reaction (There is no continued change in the super luminescence
intensity, but abrupt appearance or disappearance of super luminescence
with temperature variation). NTC of an endothermic reaction can result
in avalanche-like cooling and avalanche-like growth of reaction velocity
in active medium.
Is it possible to
use the described above properties of nitrogen oxidation reaction for
enhancing its velocity and thus for enhancing the excited molecules
concentration? If EEE would be performed in a long reactor open at one
end, the active medium would have a possibility to expand adiabatically
through the open end. During such expansion the product L*n will remain
constant (n - is concentration of excited molecules, L – is the length
of the part of reactor occupied by active medium of EEE). For this
reason the value of optical amplification coefficient would remain
constant too.
But lowering the temperature
resulting from adiabatic expansion of the reacting gas will cause the
enhancement of the chemical reaction rate and of super luminescence
intensity. The aim of the present work was the experimental
investigation of possibility to enhance the optical amplification
coefficient of the EEE active medium by using its adiabatic expansion.
Methods
Longitudinal
and transverse cross-sections of the reactor are shown on the figure 1.
The reactor is made of organic glass. A part (70 mm long) of one outer
angle is removed and the ferrite core of a TV fly-back transformer is
positioned at this place. Two steel electrodes are in contact with
ferrite core from inside of reactor. The minimal dimension of the
discharge gap between the electrodes makes 5 mm. Electrodes are
connected to the capacitors battery (two electrolytic capacitors with
capasity1000 μF, charged to 220 V on each of them). The circuit of
electrical connections is shown on figure 2.
For
the experiments with adiabatic expansion of the EEE active medium two
additional elements were fitted to the open end of the reactor. These
additional elements ("box" and "nozzle") are shown on the figure 3.
Results of Experiments
Setting
of the switch "Bk" in the "on" position results in 440 V Voltage being
applied to the steel electrodes pressed to ferrite core. EEE develops in
the discharge gap. At these conditions the radiation of EEE forms
rather broad light spot on the white screen remote at 15 cm from the
discharge zone (Figure 4).
Attaching of the steel box to the open end
of the reactor resulted in abrupt change of the light spot appearance
on the screen (Figure 5). The light spot looked then like a rectangular
with sharply shaped borders. It means that this light sport was formed
by parallel beams. Indeed: in case when some light source radiates in
all directions inside a box open at one end, the penumbras are to be
observed at the screen. We do not observe any penumbras, thus we
conclude about parallel beams. In addition to that the light spot is
displaced from the axis of the reactor. Such appearance indicates that
the light spot is produced by the stimulated (not spontaneous) emission
of radiation. In case of spontaneously radiating light source inside a
box open at one end the maximum of illumination on the screen should be
observed at the axis of the reactor. The stimulated emission produces
maximum at the direction of maximal longitude of active medium. It can
be noted that the spontaneous emission of radiation also made some
contribution to the even illumination of the screen near the point of
intersection between the reactor axis and the screen.
Fitting
of the "nozzle" to the open end of the reactor resulted in abrupt
narrowing of the light spot (Figure 6). In this case the light source
responsible for the observed light spot is located in the enlarging part
of the nozzle (out of the reactor). It means that the active medium
formed by EEE in air leaved the discharge zone at the beginning, then
came through the critical section of the nozzle and only thereafter
produced a super luminescence pulse which caused the appearance of the
compact light spot on the screen (Figure 6).
Discussion
What
can be said about the gaseous medium, which produces super luminescence
(Figures 5 and 6)? Initially it was air mixture, then EEE was initiated
in it, then it moved from the discharge gap into additional element
("box" or "nozzle") fitted to the reactor. During this transfer its
temperature lowered. The time interval between EEE and the transfer of
reacting gas in the attached element is 1 millisecond by the order of
magnitude. The equal time was needed for the spontaneous inflammation of
the EEE products at the conditions of [8]. The spontaneous inflammation
in [8] was observed only inside of optical resonator. In present work
the loss of active molecules into environment was lower due to
application of fitted elements. It could result in spontaneous
inflammation in absence of optical resonator.
The great difference
between light spots at Figures 5 and 6 can be explained by more intense
cooling of gas in the nozzle and therefore the additional rise of
reaction velocity and excited molecules concentration. The temperature
dependence of the NO-O chemiluminous recombination [7] can explain the
observed rising of optical amplification coefficient by two orders of
magnitude in assumption that the temperature in case of Figure 6 was
about 90 K. Such a great temperature lowering is possible only in an
avalanche like cooling process resulting from combination of NTC and
endothermic reaction (4).
Conclusions
The
conclusion of work [8] about the possibility of spontaneous ignition in
products of EEE in air is confirmed. The spontaneous ignition in the EEE
active medium is characterized by NTC. The energy balance of entire
nitrogen oxidation process is in agreement with proposed mechanism (1) -
(4). These facts can be used in experiments with EEE products transfer
aimed to initiation of EEE in bigger air volumes to enhance nitrogen
oxides yield and laser generation energy.