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1.
The influence of N2 and O2 molecules on spontaneous microwave radiation spectrum was studied over the decimeter range. This radiation appears in the D and E upper earth atmosphere layers during strong magnetic storms. It was shown to be caused by radiation transitions between medium-perturbed orbitally degenerate Rydberg atom and molecule states A** that occur without changes in the principal quantum number, δn = 0. The available experimental data were used to calculate the dependences of orbitally degenerate state populations on the density of medium and electron flux and temperature. Effective radiation bands were constructed for transitions between highly excited quasi-molecule levels A**N2 and A**O2. The emission spectrum was shown to be inhomogeneous and contain three frequency regions in which a noticeable decrease in the intensity of radiation occurred. The physical reason for the formation of these regions was a shift of the emission spectra of quasi-molecules containing unexcited N2 and O2 molecules. The frequency profiles of radiation intensity within these frequency regions were calculated as depending on the storm level. Radiation profiles were shown to noticeably change as the storm level increased, they strongly increased close to the right region edge corresponding to high transition frequencies. Nonmonotonic behavior of this profile in the middle of the lower region was observed; this was related to emission spectrum inhomogeneity. A sharp increase in radiation intensity as the magnetic storm level increased occurred in the region of frequencies situated close to the right edge of the upper region (50–100 GHz), which was most interesting for biophysical studies of the action of microwave radiation on living organisms during strong geomagnetic disturbances.  相似文献   

2.
We describe a method for automated measurement of the integrated sensitivity of solar cells (SCs) and multielement photoconverters (MPCs) using an experimental apparatus including a Pentium III personal computer (PC), an HP-34401A digital multimeter (DM), a stabilized radiation source (SRS), a controllable focusing system, an X-Y positioning device based on CD-RW optical disk storage devices. The method provides high accuracy in measuring the size of photosensitive areas of the solar cells and multielement photoconverters and inhomogeneities in their active regions, which makes it possible to correct the production process in the development stage and during fabrication of test prototypes for the solar cells and multielement photoconverters. The radiation power from the stabilized radiation source was ≤1 W; the ranges of the scanning steps along the X, Y coordinates were 10–100 μm, the range of the transverse cross sectional diameters of the focused radiation beam was 10–100 μm, the measurable photocurrents were 10−9 A to 2 A; scanning rate along the X, Y coordinates, ≤100 mm/sec; relative mean-square error (RMSE) for measurement of the integrated sensitivity of the solar cells, 0.2 ≤ γS int ≤ 0.9% in the ranges of measurable photocurrents 1 mA ≤ Iph ≤ 750 mA and areas 0.1 ≤ A ≤ 25 cm2 for number of measurements equal to ≤ 2· 105; instability of the radiation power (luminosity) ≤ 0.08% for 1 h or ≤ 0.4% for 8 h continuous operation; stabilized power range for the stabilized radiation source, 10−2–102 W. The software was written in Delphi 7.0. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 5, pp. 670–675, September–October, 2006.  相似文献   

3.
The IR absorption, emission, and reflectance spectra of (CO) i (H2O)20, 1 ≤ i ≤ 10, clusters were calculated using the molecular dynamics model. After the adsorption of CO molecules by clusters, IR radiation absorption and reflection by the system composed of them weakened, whereas thermal radiation power increased. We tracked changes in spectral characteristics as the number of molecules in clusters increased. Growing water clusters decreased absorption and gradually increased IR emission power. The growth of a water cluster with the addition of CO molecules to it as a rule caused the opposite effect. On the whole, clusterization and the entrapment of CO molecules by clusters had an antigreenhouse effect.  相似文献   

4.
Four predictions of Mills’ Grand Unified Theory of Classical Physics (GUTCP) regarding atomic hydrogen undergoing a catalytic reaction with certain atomized elements and ions which resonantly, nonradiatively accept integer multiples of the potential energy of atomic hydrogen, m · 27.2 eV wherein m is an integer, have been confirmed experimentally. Specifically, a catalyst comprises a chemical or physical process with an enthalpy change equal to an integer multiple m of the potential energy of atomic hydrogen, 27.2 eV. For He+ m = 2, due to its ionization reaction to He2+, and two H atoms formed from H2 by collision with a third, hot H can also act as a catalyst with m = 2 for this third H. The product is H(1/p), fractional Rydberg states of atomic hydrogen called “hydrino atoms” wherein n = 1/2, 1/3, 1/4, …, 1/p(p≤137 is an integer) replaces the well-known parameter n = integer in the Rydberg equation for hydrogen excited states. The predictions for the hydrino reaction of (1) pumping of the catalyst excited states, (2) characteristic EUV continuum radiation, (3) fast H, and (4) hydrino products were observed in multiple catalyst-hydrogen plasma systems.  相似文献   

5.
A method was developed for calculating the vibronic potential energy surfaces (PESs) of atmospheric complexes consisting of orbitally degenerate Rydberg nitrogen and oxygen molecules and the molecules of a neutral medium in the ground electronic state. The degenerate states are formed as a result of l-mixing in the D and E layers of the atmosphere during the periods of increased solar activity. The complexes are populated in the nonequilibrium two-temperature plasma and are responsible for the incoherent additional background radiation in the decimeter (microwave) and terahertz (IR) bands at an altitude of 80–110 km from the Earth’s surface. To describe the interaction of a weakly bound electron with a singly charged molecular ion and a neutral molecule of a gas medium, the formalism of the multichannel quantum defect (MCD) theory was used. Quantum-chemical calculations of the dependences of the scattering lengths, polarizabilities, and quadrupole moments of the main atmospheric molecules N2 and O2 on the interatomic distance were performed. The specific features of the behavior of vibronic PESs of Rydberg complexes for large values of the principal quantum number (n ? 1) were analyzed. The vibronic PESs of orbitally degenerate states were constructed. They are necessary for determining the positions and shape of the vibronic minima of the l-mixing cross sections of the N2 and O2 Rydberg molecules in the D and E layers of the Earth’s atmosphere, where the delay times of satellite positioning signals should be minimum. The possibility of “quantum chaos” appearing in the Rydberg complexes at sufficiently large n values and angular momenta of the weakly bound electron was noted.  相似文献   

6.
The influence of neutral species in the E- and D-layers of the Earth’s upper atmosphere on the spectrum of the spontaneous emission (absorption) of Rydberg atoms and molecules for transitions that occur without changing the principal quantum number (Δn = 0) is examined. Along with the process of l-mixing, the splitting of orbitally degenerate states due to interaction with perturbing neutral species of the medium is taken into account. The possible types of radiative transitions between them are analyzed. It is demonstrated that, for principal quantum numbers of n = 10–30, decimeter-band radiation corresponds to transitions between the levels of split states, whereas meter-band radiation, to transitions between their individual components. It is established that, for these values of n, the ratios of the intensities of the decimeter and meter bands for Δn = 0 transitions to the intensity of IR radiation (Δn = 1) are 10−4 and 10−6, respectively. The issue of satellite signal phase shift because of multiple Raman scattering in the D-layer of the atmosphere is discussed.  相似文献   

7.
Processes involving a change of orbital angular momentum l and the dissociation of Rydberg molecules when they collide with inert-gas atoms are considered, using a method based on analyzing the terms of the interacting systems. The proposed method makes it possible to take into account the perturbations in a large group of Rydberg states that weakly penetrate into the ion core and to go beyond the limits of the two-level approximations [R. F. Stebbings and F. B. Dunning, eds., Rydberg States of Atoms and Molecules (Cambridge University Press, Cambridge, 1983; Mir, Moscow, 1985)] widely used in the theory of l mixing with the participation of Rydberg atoms. Using the Na**(nd)+Xe reaction as an example, it is demonstrated that this method gives good results in a wide range of variation of the principal quantum number n of the Rydberg electron (n≈10–40). Features of the l mixing and dissociation of Rydberg molecules are studied for the H2**+Xe system. It is shown that collisional dissociation occurs by the formation of an intermediate Rydberg state of the molecules, followed by self-decay into a dissociative continuum. Zh. éksp. Teor. Fiz. 114, 100–113 (July 1998)  相似文献   

8.
For some one-parameter setH N of linear combinations ofN(N−1)/2 elementary transpositions {P jk} (1≤j<kN) at arbitrary naturalN≥3 one can construct a variety {I m} (3≤mN) of operators which commute withH N. Being applied toSU(n) spin representations of the permutation group, this proves the integrability of 1D periodic spin chains with elliptic short-range interaction. Presented at the 9th Colloquium “Quantum Groups and Integrable Systems”, Prague, 22–24 June 2000.  相似文献   

9.
Investigation was performed on luminescent properties of novel Gd2−x Eu x MoB2O9 (0.02≤x≤2.0) phosphors. The excitation spectra consist of broad band and intense narrow lines. The 4f-4f transitions are situated in a favorable position for excitation by GaN chip emission. The emission spectra consist of transitions from the 5D0 level to the lower 7F manifold, and the emission shows no concentration quenching at higher doping level. The decay time spectra of the 5D07F2 emission are recorded. Under 395 nm excitation, the intensity of 5D07F2 transition of GdEuMoB2O9 is 1.2 times stronger than that of commercial Eu3+:Y2O2S phosphor. Gd2MoB2O9:Eu3+ phosphors are promising candidates for near-UV-based solid-state-lighting (SSL).  相似文献   

10.
Summary We present the results of a search for very high energy γ-rays (E γ≈100 TeV) from SN 1987A between August 1987 and May 1988. No counting rate excess from the source is observed. The larger enhancement is seen in January 1988, but is statistically not significant (1.4 s.d.). The derived upper limits to the γ-ray and proton luminosities of the SN areL γ≤1.9·1040 erg/s andL p≤1.2·1042 erg/s. To speed up publication, the proofs were not sent to the authors and were supervised by the Scientific Committee.  相似文献   

11.
The molecular dynamics method is used to investigate the interaction of two, four, and six chloride ions with (H2O)50, clusters absorbing six ozone molecules. Chloride ions moving toward the cluster penetrate into it. The presence of ozone increases the residence time of Cl ions in the cluster. The duration of the perturbation increases with the number of Cl ions surrounding the 6O3 + (H2O)50 system. The interaction with Cl ions enhances the positional disorder of the molecules in the system and enhances the intensity of absorption and emission of infrared radiation. These changes, however, are not monotonic function of the number of ions perturbing the system. As a result of the interaction with Cl ions, the integrated intensity of the Raman scattering on the (O3)6(H2O)50 cluster in the frequency range 0 ≤ ω ≤ 1100 cm−1 is significantly lower and the number of peaks in the spectrum is smaller.  相似文献   

12.
We present the study of μp atom scattering in solid hydrogen. Anomalously large emission of E pμ≤1.9 meV μp's from a solid H2 layer was observed for the first time. This three times greater μp atom yield is due to non-elastic phonon scattering. As a result, it becomes possible to generate an ultracold flux of μp atoms. The recent calculations of the total and differential cross sections agree with all experimental results of μp atom scattering in solid H2. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

13.
The amorphous fine particles of Fe100−x B x (20.7≤x≤36.5) and (Fe70Co30)100−x B x (26.9≤x≤40.2) were prepared by borohydride reduction. The amorphous state of the samples was identified with both X-ray and electron diffraction measurements. With increasing boron content, the average hyperfine magnetic fields decrease. Comparing the hyperfine parameters of the glassy powder with those of the ribbons having the same compositions, the average hyperfine fields and the isomer shifts are different. The differences may be due to the amorphous polymorphism which is produced by the different preparation methods. Project is partly supported by the National Natural Science Foundation of China.  相似文献   

14.
The kinetic properties of ferromagnetic Ni3Al1 − x Mn x alloys with x ≤ 0.6 are studied at T ≤ 800 K and H ≤ 7 MA/m. The behavior of the electrical resistivity, the thermopower, the magnetoresistance, the Hall effect, and the spontaneous Hall effect are analyzed in the range of transition from band (Ni3Al) to spinlocalized (Ni3Mn) ferromagnetism at x ∼ 0.15.  相似文献   

15.
New values of a number of kinetic constants of processes proceeding in oxygen-iodine laser media are presented. The total probabilities of formation of I2(X, 15 ≤ v ≤ 24) and I2(X, 25 ≤ v ≤ 47) molecules in the course of quenching of I* atoms by I2(X) are found to be 0.9 and 0.1, respectively. The quantum yield of singlet oxygen in the reaction O(1 D) + N2O → N2 + O2(a 1Δ) is close to 100%. The quenching rate constants of I2(A’) by O2, H2O, CO2, I2, and Ar and of I(2 P 1/2) by O(3 P), O3, NO2, N2O4, and N2O are presented.  相似文献   

16.
The objective of the research outlined in this paper was to develop the analytical approximations for calculating real-gas properties (p-v-T data, thermodynamic functions: internal energy, enthalpy, and entropy, and specific heats) of vapor-phase n-alkanes from C1 (methane) to C14 (normal tetradecane), O2, N2, H2O, CO, CO2, and H2 within the range of pressure 0.05 MPa ≤ p ≤ 20 MPa and temperature 280 K ≤ T ≤ 3000 K aimed for implementation into computational fluid dynamics (CFD)-codes simulating the operation process in modern Diesel engines. The analytical approximations have been developed based on available literature data and on the new equation of state for moderately dense gases. The approximations reported are rather simple and therefore can be used directly in CFD codes. Approximations for mixing rules are also provided.  相似文献   

17.
A method is proposed for measuring extragalactic magnetic fields in observations of TeV γ rays from distant sources. Multi-TeV γ rays from these sources interact with the infrared photon background producing secondary electrons and positrons, which can be just slightly deflected by extragalactic magnetic fields before they emit secondary γ rays via inverse Compton scattering of cosmic microwave background photons. Secondary γ rays emitted toward an observer on the Earth can be detected as an extended emission around an initially point source. The energy dependent angular profile of the extended emission is related to the strength of the extragalactic magnetic field along the line of sight. Small magnetic fields B ≤ 10−12 G in the voids of the large scale structure can be measured in this way. The text was submitted by the authors in English  相似文献   

18.
Emission characteristics of ultraviolet (UV) radiation from water vapor (H2O, D2O, and a mixture of H2O and D2O vapors) excited by pulse-periodic discharges with open electrodes, as well as electrodes outside the discharge tube (capacitive discharge), are presented. Radiation is studied in a spectral range of 175–350 nm. The emission characteristics of a UV radiation source based on vapors of ordinary and “heavy” water, as well as the results of optimization of brightness of radiation bands from the OH and OD radicals as functions of pressure and the composition of the He-H2O and He-D2O mixtures, are reported.  相似文献   

19.
A problem of acoustic radiation propagation through a 500-m layer of the plane-stratified turbulent atmosphere is solved by the Monte Carlo method. Quantitative estimates of variations of the multiple scattering contribution to the transmitted radiation intensity are presented. Calculations were performed for mid-latitude regional models of the atmosphere in winter and summer in clear and cloudy days for a point-sized omnidirectional source placed at altitudes Hs = 5–35 m above the Earth’s surface. Results of calculations for sound frequencies in range F = 500–4000 Hz with a step of 500 Hz and for outer scale of turbulence L0 = 1–5 m with a step of 1 m and 10–100 m with a step of 10 m demonstrate significant regional and seasonal variability of the multiple scattering contribution. __________ Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 86–90, October, 2007.  相似文献   

20.
The effect of atomic disordering induced by melt quenching or severe plastic deformation via high-pressure torsion on the physical properties (thermal expansion coefficient, electrical resistivity, thermoelectric power, magnetization) of a stoichiometric Ni50Mn25Ga25 alloy and nonstoichiometric Ni50Mn28.5Ga21.5 alloys with 2 at % Cu or Co is studied in the temperature range 2 K ≤ T ≤ 900 K and the magnetic field range H ≤ 7 MA/m.  相似文献   

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