A moment method based solution for the electromagnetic radiation and scattering from geometries composed of transverse dipole column arrays and a finite collection of axial slot arrays is developed. Each 'array' is an infinite column of periodic elements, with transverse referring to a dipole orientation perpendicular to the infinite axis and axial denoting that thin linear slots are directed along the infinite axis. The slots are mounted in infinite ground planes, which may be surrounded by an...
Topics: DTIC Archive, Skinner, J P, AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH, *DIPOLE ANTENNAS,...
We present numerical results from long-term CPU and GPU simulations of rotating, homogeneous, magnetohydrodynamic (MHD) turbulence, and discuss their connection to the spherically bounded case. We compare our numerical results with a statistical theory of geodynamo action that has evolved from the absolute equilibrium ensemble theory of ideal MHD turbulence, which is based on the ideal MHD invariants are energy, cross helicity and magnetic helicity. However, for rotating MHD turbulence, the...
Topics: NASA Technical Reports Server (NTRS), ALIGNMENT, DIPOLE MOMENTS, MAGNETOHYDRODYNAMIC TURBULENCE,...
The Asian southwest monsoon (SWM) east of the Horn of Africa (HOA) is important in planning and conducting maritime operations in this region. Skillful subseasonal to seasonal (S2S) forecasts of the SWM onset are needed for operational planning but are not yet available. We investigated the potential for S2S forecasting of the onset of SWM surface winds and ocean surface waves off HOA by analyzing global atmospheric and oceanic variables, and three onset states: early, normal, and late. We...
Topics: climate, climate variations, climate analysis, long-range forecasting, subseasonal to seasonal,...
Low frequency phonon modes of a helical DNA olygomers- were calculated and compared. The customized program -cages JiMA and UGAND (developed in Dr. Laverys group lBPc. Paris) were was adopted for IBM PC and employed to minimize potential energy and to calculate vibrational frequencies of a molecule. The initial geometry for the B-helix oligonucleotides d(TATATATATATA)d(ATATATATATA) and d(A AAAAAAAAAAA)d(TTTTTTTTTTTT) was created by program JUMNA. The energy of interatomic interactions was...
Topics: DTIC Archive, Bykhovskaia, Maria, VIRGINIA UNIV CHARLOTTESVILLE, *DEOXYRIBONUCLEIC ACIDS,...
The equation for pitch-angle diffusion (at constrant particle energy E and shell parameter L) in a dipole field can be transformed into canonical form, by the introduction of a new coordinate called z. The new coordinate is obtained by integrating the bounce period of a particle (at fixed E and L) with respect to y sq, where y is the sine of the equatorial pitch angle alpha sub 0. A potpourri of applications serves to illustrate the usefulness of such a transformation. For example, if D sub zz...
Topics: DTIC Archive, Schulz,Michael, AEROSPACE CORP EL SEGUNDO CA SPACE SCIENCES LAB, *PLASMAS(PHYSICS),...
The optimum gain of uniformly spaced arrays of isotropic sources or dipoles is investigated theoretically in this paper. The formulation is processed with the aid of an array matrix. The optimum gain and the corresponding excitation are expressed directly in terms of the elements of the array matrix.
Topics: DTIC Archive, Tai, C T, OHIO STATE UNIV RESEARCH FOUNDATION COLUMBUS ANTENNA LAB, *DIPOLE ANTENNAS,...
The nomographic procedures described are devised for facilitating computation of values for wave arrival angles obtained from a 3-station receiver system. The original effort was conducted to simplify the resolution of the angle-of-arrival vector from component measurements made on a wideband 3-port receiving system at a field site. The particular 3-port configuration uti lized three wideband, vertically polarized, mono pole antennas placed at the apexes of an equilateral triangle.
Topics: DTIC Archive, Phillips, M L, ACF INDUSTRIES INC HYATTSVILLE MD ELECTRO-PHYSICS LABS, *ANGLE OF...
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Jan 18, 2021
01/21
by
Andrey Morenko (_MFer_)
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This is a simple dipole holder - way up guider to avoid props. I use MMCX dipole from AKK: https://www.akktek.com/akk-mmcx-linear-antenna.html But it will go with any tiny dipole connected directly to your VTX. Print it with some flexible filament (TPU, B-Flex, etc)
Topics: dipole, thingiverse, mount, mode2, R/C Vehicles, frame, stl, ghost
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239
Jun 20, 2010
06/10
by
Garron, R
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Dipole moment of double layer of metallic surfaces
Topics: CRYSTAL SURFACES, DIPOLE MOMENTS, METAL SURFACES, SURFACE LAYERS, ELECTRONS, SURFACE ENERGY, WAVE...
Work completed under this grant on polar fluids includes an extension of perturbation theory to polar molecules with point octopoles and hexadecapoles as well as a preliminary investigation of molecules with non-spherical cores. In addition, the ordering of dipolar molecules near a flat electrified wall has been investigated in the linearized hypernetted chain (LHNC) and quadratic hypernetted chain (QHNC) approximations. This has led to a new study of electrostriction and non-linear effects in...
Topics: DTIC Archive, Rasaiah, Jayendran C, MAINE UNIV AT ORONO, *PERTURBATIONS, *FLUID DYNAMICS,...
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0.0
Jan 4, 2021
01/21
by
bopiloot maker (bopiloot)
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Light weight R9 Dipole T Antenna mount for the Diatone R349 / T-Motor TM-3419 frame. This get's mounted with 4 zip ties. The hole allows for a zip tie of max. 2,5x1,2mm Printed with the Sparkmaker LSA printer but the model lends itself also for regular filament printing. Check my entire design collection on Cults3d.com https://cults3d.com/en/users/bopiloot/creations Happy crafting!! * Added reinforced version (10% added weight)
Topics: r349, diatone_gt, r9mm, tbs, Tbs_crossfire, r9mini, diatone, antenna_mount, Hobby, tm3419,...
In this paper a flexible low profile dipole antenna using a frequency selective surface (FSS) with interdigital barium strontium titanate (BST) varactor-tuned unit cells is presented. The varactor chips were placed only along one dimension of the FSS to avoid the use of vias and simplify the DC bias network. The antenna uses overlapping metallic plates that resemble fish scales as a ground plane to improve the flexibility of the multi-material stack structure. The measured data of the antenna...
Topics: NASA Technical Reports Server (NTRS), DIPOLE ANTENNAS, FLEXIBILITY, BARIUM TITANATES, VARACTOR...
This report summarizes the results of intensities and broadening coefficients measurements performed on 12C1602 lines in the 13.5 micrometers region. The used spectra were recorded at high resolution with a Fourier transform spectrometer. From the intensities measurements it has been possible to derive the variation of the square of the transition dipole moment (u)2 with respect to the rotational quantum numbers. Keywords: Infrared, Intensities, Broadening coefficients, Carbon Dioxide.
Topics: DTIC Archive, Dana, Victor, PARIS-6 UNIV (FRANCE) LAB DE PHYSIQUE MOLECULAIRE AND ATMOSPHERIQUE,...
The application of carbon nanotube (CNT) materials to produce lightweight, flexible, and durable alternatives to existing and future Army antenna designs is explored through simulation and material fabrication and characterization. The conductivity and current distribution for a dipole antenna constructed from CNT thread/rope are simulated using Hallns integral equation for a thin wire applied to the method of moments. A variety of CNT thread/rope samples are fabricated and their physical and...
Topics: DTIC Archive, Keller,Steven D, US Army Research Laboratory Adelphi United States, carbon nanotubes,...
Motivations listed for compact high performance radiofrequency communations. Whip antennas for High Frequency communications need to contain the following: 1. Simple classic design; 2. Narrow bandwidth; 3. High visibility; 4. Needs assembly for portability. Ribcage dipole antenna: 1. Low profile; 2. Excellent performance over a ground plane; 3. Wide impedance bandwidth; 4. Uniform antenna pattern over the bandwidth; 5. Needs further development and funds.
Topics: DTIC Archive, PHYSICAL SCIENCES INC ANDOVER MA, *ANTENNA ARRAYS, *DIPOLE ANTENNAS, *WHIP ANTENNAS,...
R&D Report 1962-07 : The use of overhead power lines to provide a VHF broadcasting service. R.G. Manton, P. Knight The provision of an adequate television or v.h.f. f.m. service in a mountainous area presents considerable difficulty since a large number of low-power relay stations is required. A possible alternative is the use of existing over-head power lines for the both the transmission and radiation of the services throughout an area. In this report, the service area which could be...
Topics: power, radiation, lines, propagation, cross, spaced, dipole, field, currents, dipoles, power flow,...
R&D Report 1965-13 : Transmitting aerials for the Granton VHF television and VHF sound station D.W. Osborne, R.D.C. Thoday The Grantown relay station came onto operation on 8th February 1965. It provides a television and v.h.f sound service to Grantown, Nethy Bridge, Boat of Garten, Carrbridge and Duthil; parts of Aviemore are also served.
Topics: aerial, horizontal, dipole, tiers, gain, templet, transmitting, band, tower, radiation, radiation...
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0.0
Jan 6, 2021
01/21
by
Dennis FiveLeafCloverFPV (TurboCinqy)
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No special settings 1km test flight.. - 80dB @ 100mW https://youtu.be/pauiYFWNCPE
Topics: R/C Vehicles, discovery, stl, diversity, TBS_Discovery, tbs_nano, TBS_nano_diversity,...
A field effect transistor with metal gate suspended above the gate insulator has been fabricated. Fluid samples can freely penetrate into the gap formed between the metal and the insulator. If the molecules carry an electrical dipole, they will alter the surface potential on these two materials giving rise to a change in the drain current of the transistor. Our preliminary results confirm this mechanism for dipolar molecules such as methanol and methylene chloride. (Author)
Topics: DTIC Archive, Blackburn,Gary F, UTAH UNIV SALT LAKE CITY DEPT OF BIOENGINEERING, *Field effect...
Significant research and press has recently focused on the fabrication freedom of Additive Manufacturing (AM) to create both conceptual models and final end-use products. This flexibility allows design modifications to be immediately reflected in 3D printed structures, creating new paradigms within the manufacturing process. 3D printed products will inevitably be fabricated locally, with unit-level customization, optimized to unique mission requirements. However, for the technology to be...
Topics: NASA Technical Reports Server (NTRS), COMPUTER AIDED MANUFACTURING, RAPID PROTOTYPING, LAMINATES,...
Bell System Technical Journal, 16: 4. October 1937 pp 493-512. The Dielectric Properties of Insulating Materials. (Murphy, E.J.; Morgan, S.O.)
Topics: dielectric, polarizations, polarization, frequency, dispersion, atomic, dipole, constant,...
Bell System Technical Journal, 16: 1. January 1937 pp 101-109. Series for the Wave Function of a Radiating Dipole at the Earth's Surface. (Rice, S.O.)
Topics: arg, dipole, series, wave, integral, asymptotic, contour, function, deformation, equation, unit...
Folkscanomy Electronics Articles: ARRL Basic Antennas
Topics: fig, antenna, dipole, antennas, impedance, transmission, array, swr, azimuth, element, azimuth...
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0.0
Mar 5, 2021
03/21
by
Frank Werner (Tommy0)
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Dipol- Halter- Center für eine Hühnerleiter 450 Ohm. Das Gegenstück gibt es hier: https://www.thingiverse.com/thing:3193948 Siehe auch: https://www.thingiverse.com/thing:3992143
Topics: Antenne, Dipolhalter, Hamradio, 450_ohm, ham_radio_dipole, amateur_radio, dipole_antenna,...
R&D Report 1964-17 : Transmitting aerial for the Holyhead VHF television station D.W. Osborne A brief summary of installation of Holyhead relay station.
Topics: aerial, transmitting, horizontal, tower, height, technological, channel, holyhead, dipoles, dipole,...
Bell System Technical Journal, 8: 4. October 1929 pp 662-671. Asymptotic Dipole Radiation Formulas. (Wise, W. Howard)
Topics: asymptotic, dipole, sin, equation, wave, horizontal, dipoles, formulas, radiation, vertical,...
A general formulation for the back-scattered field from loaded objects is given. It is shown that small resonant objects produce a much greater back-scattered field than small nonresonant ones. The theory is applied to short dipoles and small loops. The use of small resonant scatterers to measure electric and magnetic fields by scattering techniques is discussed. Resonant scatterers are found to have several advantages over nonresonant scatterers when used for field measurements.
Topics: DTIC Archive, Harrington, Roger F, SYRACUSE UNIV RESEARCH INST NY, *MAGNETIC FIELDS, *ELECTRIC...
Work in several areas of laser cooling and trapping of atoms were done during the granting period. Work in atom manipulation with Raman pulses of light, atom interferometers, atomic fountain frequency standards, a new technique in subrecoil laser cooling, novel far detuned optical dipole traps, polymer experiments with single molecules of DNA are described. The work includes seven Physical Review Letters, two Science articles and a cover article for Science.
Topics: DTIC Archive, Chu, Steven, STANFORD UNIV CA DEPT OF PHYSICS, *TRAPPING(CHARGED PARTICLES),...
The feasibility of radiating large quantities of energy from a satellite is discussed. A system comprised of an explosive generator source, switching and matching networks, and a bent-dipole antenna is theoretically analyzed. The calculations indicate that an electric field of 4000 V/m can be produced at a distance of 1 mile from the source.
Topics: DTIC Archive, Soo Hoo, Keith M, AEROSPACE CORP EL SEGUNDO CA LAB OPERATIONS, *PULSE GENERATORS,...
A general method for exact integration of vector potentials of thin dipole antennas characterized by various current distributions is developed. Such solutions are shown to be independent of the usual far-field restrictions involving dipole length, observation point distance, and wavelength. Their convergence is rapid in the induction and near-field regions.
Topics: DTIC Archive, Overfelt,P L, NAVAL WEAPONS CENTER CHINA LAKE CA, *ANTENNA RADIATION PATTERNS, *NEAR...
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Johann Carl Friedrich Gauss (30 April 1777 – 23 February 1855) was a German mathematician who contributed significantly to many fields, including number theory, algebra, statistics, analysis, differential geometry, geodesy, geophysics, electrostatics, astronomy, Matrix theory, and optics. Earth's magnetic field, also known as the geomagnetic field, is the magnetic field that extends from the Earth's interior to where it meets the solar wind, a stream of charged particles emanating from the...
Topics: Geomagnetism, Carl Friedrich Gauss, Vonsmersh, Gauss, Magnetic, Field, Dipole
Work completed under this grant on polar fluids includes an extension of perturbation theory to polar molecules with point octopoles and hexadecapoles as well as a preliminary investigation of molecules with non-spherical cores. In addition, the ordering of dipolar molecules near a flat electrified wall has been investigated in the linearized hypernetted chain (LHNC) and quadratic hypernetted chain (QHNC) approximations. This has led to a new study of electrostriction and non-linear effects in...
Topics: DTIC Archive, Rasaiah, Jayendran C, MAINE UNIV AT ORONO, *PERTURBATIONS, *FLUID DYNAMICS,...
A theoretical model is developed to establish an adhesion criterion for the interaction of a gas atom or molecule with a nonmetallic surface. As a first approximation a linear lattice mass points of the solid surface is considered and the classical lattice dynamical model is used.
Topics: NASA Technical Reports Server (NTRS), ADHESION, GAS-SOLID INTERFACES, MOLECULAR INTERACTIONS,...
A new type of antenna array consists of dipole elements, proximity coupled to a two-wire transmission line. Scanning is accomplished by changing the spacing between elements. A method of scanning using electromechanical methods is described which is particularly useful in large antenna systems over the frequency range of about 50 to 500 MC.
Topics: DTIC Archive, Poirier, J L, AIR FORCE CAMBRIDGE RESEARCH LABS HANSCOM AFB MA, *COUPLED ANTENNAS,...
Research Frontiers Incorporated Panel Brochure. Includes newspaper clipping and overview. November 13, 1966
Topics: varad, dipoles, panel, frontiers, panels, dipole, polarized, power, prototypes, incorporated,...
Finitely conducting earth-image-theory techniques have been employed to determine new formulas for the electric and magnetic fields produced by the four elementary dipole antennas for the air-to-air, surface-to-air, air-to- surface, and surface-to-surface propagation cases. The only restriction on the use of these formulas is that the index of refraction be large (i.e., the absolute value of n squared > or = 10). They are valid at any frequency and at any range for the flat-earth case....
Topics: DTIC Archive, Bannister, Peter R., NAVAL UNDERWATER SYSTEMS CENTER NEW LONDON CT, *ELECTROMAGNETIC...
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373
May 28, 2011
05/11
by
Ege, Russell A.; Brown, Jerome; Bradley, Kevin; Grandi, Fabi
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To meet its objective of assisting the US aviation industry with the technological challenges of the future, NASA must identify research areas that have the greatest potential for improving the operation of the air transportation system. To accomplish this, NASA is building an Aviation System Analysis Capability (ASAC). The Noise Impact Model (NIM) has been developed as part of the ASAC. Its primary purpose is to enable users to examine the impact that quieter aircraft technologies and/or...
Topics: ABSORPTION SPECTRA, WORLD WIDE WEB, COLLISIONS, DIPOLE MOMENTS, HYDROGEN, PLANETARY ATMOSPHERES,...
The scalar reciprocity equation commonly stated in underwater acoustics relates pressure fields and monopole sources. It is often used to predict the pressure measured by a hydrophone for multiple source locations by placing a source at the hydrophone location and calculating the field everywhere for that source. That method, however, does not work when calculating the orthogonal components of the velocity field measured by a fixed receiver. This thesis derives a vector-scalar reciprocity...
Topics: reciprocity, vector field, parabolic equation, acoustic dipole
In this presentation a 2.4 GHz low profile (lambda45) tunable dipole antenna is evaluated in the presence of a human core model (HCM) body phantom. The antenna uses a frequency selective surface (FSS) with interdigital barium strontium titanate (BST) varactor-tuned unit cells and its performance is compared to a similar low profile antenna that uses an FSS with semiconductor varactor diodes. The measured data of the antenna demonstrate tunability from 2.2 GHz to 2.55 GHz in free space and...
Topics: NASA Technical Reports Server (NTRS), DIPOLE ANTENNAS, VARACTOR DIODES, AEROSPACE MEDICINE,...
03 Apr 1968 227964213
Topics: Loop antennas, Electrical impedance, Aircraft antennas, Ham radio, Amateur radio, Efficiency,...
The transient fields produced by vertical and horizontal electric dipoles with impulsive current excitation in the presence of a half-space are considered. For special source and observer configurations, exact, closed form expressions for the fields produced by impulsively excited dipoles above a nondispersive half-space are given. For the dispersive case, estimates of the transient fields from asymptotic approximations are given. A knowledge of the interactions of dipole antennas and a...
Topics: DTIC Archive, Hill, D A, OHIO STATE UNIV COLUMBUS ELECTROSCIENCE LAB, *DIPOLE ANTENNAS, *RADAR...
This research project was concerned with a theoretical investigation of the generation of electromagnetic radiation in polarizable or conducting media by relativistic charged particles. Results are contained in the following papers: Generation of Coherent X-Rays by a Relativistic Charged Particle Traveling Through a Crystal; Generation of Coherent Radiation in a Resonant Medium by a Relativistic Charged Particle, Cerenkov Radiation at the Resonance Frequency of an Amplifying Medium; Generation...
Topics: DTIC Archive, Robl,Hermann R, DUKE UNIV DURHAM N C, *EXCITATION, *DIPOLE MOMENTS, POLARIZATION,...
Cooperative electronic excitation involving electron transfer among guest molecules in a solid is considered. The mutual interaction between two guest molecules with large dipole moments in excited states can lead to cooperative processes (two-electron transfer) which are forbidden in the absence of such interaction. The cooperative transition moments are calculated for coupled pairs of XeC1 molecules within an Ar matrix at sum and difference frequencies. Keywords: Charge transfer, Solid,...
Topics: DTIC Archive, Last, Isidore, STATE UNIV OF NEW YORK AT BUFFALO AMHERST, *CHARGE TRANSFER,...
The determination of foreign communications capabilities and intent is an important assessment function performed by the USAF National Air Intelligence Center (NAIC). In this context, Rome Laboratory became the NAIC engineering agent for the development of an NAIC requirement for the rapid analysis and evaluation of antenna structures based on often vague to sometimes detailed dimensional information. To this end, the Rome Laboratory sponsored development of the Electromagnetic Antenna Modeling...
Topics: DTIC Archive, Packer, Malcolm, SCIENCE APPLICATIONS INTERNATIONAL CORP STOW MA, *COMPUTERIZED...
Reliable adiabatic potential curves for the 5 Sigma (+) sub g and 3 Sigma (+) sub u states of He2 which correspond to the interaction of a pair of 1s2s 3S atoms are determined variationally by configuration interaction (CI) calculations comprising single and double excitations from small internuclear separations in addition to one in the intermediate region which is about 3430/cm deep. The quintet has a van der Waals well nearly 900/cm deep. The outer well of each state supports about 20 bound...
Topics: DTIC Archive, Konowalow,Daniel D, ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD,...
Measurements of propagation at a frequency of 1090 MHz over terrain that produces specular reflection and knife-edge diffraction are in good agreement with model calculations that use images to represent the effect of reflection. A hill covered with a pine forest formed the deffracting mask, and an airport area formed the reflecting surface. Agreement between measurements and model calculations required that the diffracting knife-edge be located at treetop level. Optimum propagation into the...
Topics: DTIC Archive, Meeks, M. L., MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB, *ELECTROMAGNETIC WAVE...
The infinite modulated reactance sheet is studied with the phase and amplitude contours of the near field presented. It is shown that the infinite reactance sheet is an excellent description of the modulated Yagi. Experiment al radiation patterns of low-sidelobe endfire arrays are given together with radiation patterns of Yagi arrays giving cosecant type radiations, flat-top flared beams, and beams at an arbitrary angle. The beams at an arbitrary angle are ob tained from a cosine to the even...
Topics: DTIC Archive, Thomas, Abdelnour S, THOMAS (A S) INC WESTWOOD MA, *DIPOLE ANTENNAS, *ANTENNA LOBES,...
From measured waveforms it has been determined that the electromagnetic pulse from a nuclear detonation is associated with the gradual establishment of a large dipole moment, which remains suspended in the atmosphere at the conclusion of the EMP waveform. From the gradual growth and the large magnitude, it is inferred that the source-current region is large, and that retardation across this source-current region is an important aspect of the EMP phenomenon. Retardation is also important in...
Topics: DTIC Archive, Clapp, Roger E, AIRTECHNOLOGY CORP WALTHAM MA, *NUCLEAR EXPLOSIONS, *ELECTROMAGNETIC...
This report discusses extending the results for prolate spheroids by including higher order modes and finding the sum of modes giving the minimum radiation Q. There is no coupling between odd and even modes, but there is coupling between the lowest order even modes. The report also presents a simple result for the values of the degree of mixing of modes 2, 4, and 6 that minimizes Q(sub r).
Topics: DTIC Archive, Adams, R C, SPACE AND NAVAL WARFARE SYSTEMS CENTER SAN DIEGO CA, *DIPOLE ANTENNAS,...
Linear carbon-chain radicals C(sub n) H for n = 2-7 have been studied with correlation consistent valence and core-valence basis sets and the coupled cluster method RCCSD(T). Equilibrium structures, rotational constants, and dipole moments are reported and compared with available experimental data. The ground state of the even-n series changes from 2Sigma(+) to 2Pi as the chain is extended. For C4H, the 2Sigma(+) state was found to lie only 72 cm(exp -1) below the 2Pi state in the estimated...
Topics: NASA Technical Reports Server (NTRS), CARBON, RADICALS, DIPOLE MOMENTS, MOLECULAR CLOUDS, GROUND...
