text:
|Numéro de publication
|Type de publication
|Date de publication
|7 oct. 1975
|Date de dépôt
|4 févr. 1974
|Date de priorité
|29 mars 1972
|Numéro de publication
|Donald M Spero, Bernard J Eastlund, Michael G Urv
|Cessionnaire d'origine
|Fusion Systems Corp
|Exporter la citation
|BiBTeX, EndNote, RefMan
|Citations de brevets (9), Référencé par (123), Classifications (29)
|Liens externes: USPTO, Cession USPTO, Espacenet
United States Patent Spero et al. Oct. 7, 1975 [5 METHOD AND APPARATUS FOR 3,541,372 11/1970 Omura et al. 315/111 GENERATING ELECTROMAGNETIC 5233 2; 313;} isq l rams RADIATION 3,641,389 2/1972 Leidigh..... 315/39 [75] Inventors: Donald M. Spero, Bethesda; 3,663,858 5/1972 Lisitano 315/39 Bernard J. Eastlund, Rockville; Michael G. Urv, Lanham, all of Md. Primary ExaminerSaxfield Chatmon, Jr. [73] Assignee: Fusion Systems Corporation, l il fi Flrm Browne Bevendge Rockville, Md.
[22] Filed: Feb. 4, 1974 57 ABSTRACT [21] Appl. No.: 439,173 There is disclosed a novel method and a aratus for PP Related U S A cation Data generating high power electromagnetic radiation in pp the ultraviolet and visible regions of the electromag- [62] Y of 239N191 March 1972 netic spectrum wherein high energy electrons, proabdndoned' duced by directing a lower frequency (radio to microwave) electromagnetic energy wave into a plasma pro- [52] US. Cl. 315/39, 225sOo/jl59ji235l0sl/5l0l4l, ducing medium (gas, vapor and mixtures thereof) are 2 caused to collide with heavy particles of the medium 2g ig ld g 3 to thereby cause same to be collisionally excited and 1 0 care g 5 6 subsequently emit electromagnetic radiation. Particular-means are disclosed for coupling the lower frequency electromagnetic wave energy to the medium. [56] References C'ted In a preferred embodiment the medium is confined in UNITED STATES PATENTS a closed vessel or chamber at a selected pressure to 3,313,979 4/1967 Landauer 315/39 which a magnetic field is applied to guide the high en- ,1 H1968 Grubcr et l ergy electrons to collision with said heavy particles. 3,374,393 3/1968 Bramlcy 315/39 3,378,723 4/1968 Napoli et a]. 315/39 5 Clams, 7 Drawmg Flgures XXI XXV FL. 5 i C, I J/ 1; 1| I H I 67" 281 MICROWAVE 1/2 I 1' :llzzgllnao acuanrron. l
l l x I US. Patent Oct. 7,1975 Sheet 1 of 3 3,911,318
U.S. Patent Oct. 7,1975 Sheet 2 of 3 3,911,318
MICROWAVE lo GENERATOR.
US. Patent Oct. 7,1975 Sheet 3 of 3 3,911,318
r 8 r464 r468 TL r r 1- 3 PLASMA REG/ON r72 @E MATERIAL PLASMA R'G/ON m MICROWAVES MICROWAVES PLAsMA TUBE wrra ri- TAPERED END TERMINATED RECTANGULAR (MAGNET cou.s NOT WAVEGUIDE SHOWN) MAG N ET COILS METHOD AND APPARATUS FOR GENERATING ELECTROMAGNETIC RADIATION This is a division of application Ser. No. 239,149, filed Mar. 29, 1972, now abandoned. su
Attention is directed to the disclosure of the following references for an exposition of background technology leading to a better understanding of the present invention:
l. K. S. Golovanivskii and V.D. Dugar-Zhabon, High Frequency Low Pressure Discharge at the Electron Cyclotron Resonance," Sov. Shys- .Tech. Phys. 16, 75 (July, 1971).
2. M.V. Krivosheev, Production of a High-Density Plasma by Microwaves in 21 Magnetic Field," Sov. Phys.Tech Phys. 15, 1805 (May, 1971).
3. V.E. Golant and M.V. Krivosheev, Anomalous Absorption of Microwave Power by a Plasma at Supercritical Electron Densities, Sov. Phys.Tech. Phys. 14, 719 (November, 1969).
4. V.E. Golant, M.V. Krivosheev, and V.I. Fedorov, Linear Wave Transformation and Absorption in a Plasma of Small Transverse Dimensions, Sov. Phys-Tech. Phys. 15, 282 (August, 1970).
5. A.l. Anisimov, NI. Vinogradov, V. Ye Golant, S.I. Nanobashvili, and L.P. Pakhomov, Super-High Frequency Generation of a Strongly Ionized Argon Plasma, AEC-tr-7056 of A.F. IOFFE Physico' Technical Institute Report No. 113, 1968.
6. V.N. Budnikov, N.1. Vinogradov, V.E. Golant, and A.A. Obukhov, Investigation of a Steady-State Microwave Discharge in a Magnetic Field, Sov. Phys-Tech. Phys. 13,19 (July, 1968).
7. A. 1. Anisimov, N.I. Vinogradov, V.E. Golant, S.I. Nanobashvili. and L.P. Pakhomov, Determination of Plasma Parameters Produced by Super High- Frequency Power in a Magnetic Field in a Steady- State Condition, AEC-tr-7052 of IOFFE Institute Report, 1968.
8. A. 1. Anisimov, N.1. Vinogradov, V.E. Golant, and LP. Pakhomov, Microwave Production of a Plasma in a Trap," Sov. Phys.-Tech. Phys. 12, 486 (October, 1967).
. V.N. Budnikov, NJ. Vinogradov, V.E. Golant, and A.A. Obukhov, Plasma Produced by Electron Cyclotron Resonance 1. Absorption of Microwave Power, Sov. Phys.Tech. Phys. 12, (November, 1967).
10. V.N. Budnikov, N.I. Vinogradov, V.E. Golant, Plasma Produced by Electron Cyclotron Resonance, 11 Charged Particle Balance, Sov. Phys .Tech. Phys. 12, (November, 1967).
l 1. V.N. Budnikov, V.E. Golant, and A.A. Obukhov, Absorption of Microwave Power by a Plasma at Magnetic Fields Above the Cyclotron Frequency, Sov. Phys-Tech. Phys. 15, 97 (July, 1970).
12. A. 1. Anisimov, V.N. Budnikov, N.I. Vinogradov, V.E. Golant, S.1. Nanobashvili, A.A. Obukhov, A.P. Pakhomov, A.D. Piliya, and V.I. Federov, Ultra-High Frequency Plasma Heating in a Magnetic Field, IAEA Conference on Plasma Physics and Controlled Fusion Research, Novosibirsk (August, 1968), paper CN-24/J-3.
13. V.N. Budnikov, V.P. Gorelik, V.V. Dyachenko, K.M. Novik, and A. A. Obukhov, Microwave Discharges at Harmonics of the Electron Cyclotron Frequency," Sov. Phys-Tech. Phys. 16, 404 (Sep tember, 1971 14. B. V. Calaktionov, V.V. Dyachenko, and O.N. Shcherbinin, High Frequency Plasma Heating Near the Lower Hybrid Frequency," Sov. Phys.- Tech. Phys. 15, 1809 (May, 1971).
15. B.V. Galaktionov, V.E. Golant, A.D. Piliya, and O.N. Shcherbinin, Plasma Absorption of RF Energy Near the Lower I-llybrid Frequency, Sov. Phys-Tech. Phys. 14, 721 (November, 1969).
16. A.D. Piliya and V.I. Fedorov, Linear Wave Conversion in an Inhomogeneous Magnetoactive Plasma, Soviet Physics JETP 30, 653 (April, 1970).
17. V.I. Arkhipenko, A.B. lBerezin, V.N. Budnikov, V. Ye Golant, K. M. Novik, A.A. Obukhov, A.D. Piliya, V.I. Fedorov, and K.G. Shakovets, Studies of the Transformation and Adsorption of High- Frequency Waves in a Plasma for the Purpose of Developing Plasma Heating Techniques, IAEA Conference on Plasma Physics and Controlled Nuclear Fusion Research, Madison, Wisconsin, June, 1971, paper CN-28/L-4.
18. A.]. Anisimov, N.1. Vinogradov, V.E. Golant, and L.P. Pakhomov, Absorption of Electromagnetic Waves in a Plasma at Frequencies Near Harmonics of the Electron Cyclotron Frequency, Sov. Phys.- Tech. Phys. 12, 141 (July, 1967).
19. V. N. Budnikov, V.E. Golant, and A.A. Obuchov, The Study of Microwave Absorption by a Plasma in a Magnetic Field," 31A, 76 (Jan. 26, 1970).
20. B.V. Galaktionov, V.E. Golant, V.V Dyachenko,
and O.N. Shcherbinin, Determination of the Limiting Frequency for Plasma Absortpion of High Frequency Waves at Frequencies between the Electron Cyctron Frequency and the Lower Hybrid Frequency, Sov. Phys-Tech. Phys. 15, 1813 (May, 1971).
21. V.E. Golant and A.D. Piliya, "Linear Transformation and Absorption of Waves in Plasma, Uspekhi Fiz. Nauk 74, No. 3 (1971).
22. G. Lisitano, M, Fontanesi, and E. Sindoni, Ap-
plied Physics Letters, 122, Feb. 1, 1970.
23. G. Lisitano, P. Caldirola, N, Barassi, M. Fontanesi, and E. Sindoni, IAEA Conference on Plasma Physics and Controlled Thermonuclear Re search, Novosibirsk, USSR, 1968.
24. Schlag, E.W. and Comes, F.J., Intense Light Sources for the Vacuum Ultraviolet II, J. Opt. Sci. Am., Vol. 50, No. 9, p. 866.
25. Wilkinson, P.G., New Krypton Light Source for the Vacuum Ultraviolet", J. Opt. Sci. Am., Vol. 45, No. 12, p. 1044.
26. Wilkinson, PG. and Tanaka, Y., New Xenon- Light Source for the Vacuum Ultraviolet J. Opt. Soc. Am., Vol 45, No. 5, p. 344.
27. Dieke G.H. and Cunningham, S.P., A New Type of Hydrogen Discharge Tube, J. Opt. Sci. Am., Vol. 42, No. 3, p. 187.
28. Okabe, I-1., Intense Resonance Line Sources for Photochemical Work in the Vacuum Ultraviolet Region, J. Opt. Sci. Am., Vol. 54, No. 4, p. 478.
29. Minnhagen, L., Review of Methods for the Excitation of Atomic and Ionic Spectra by Means of High-Frequency Discharges and Sliding Sparks, J Res. Natl. Bur. Std. (U.S.), Vol. 68C, No.4, p. 237.
30. Warneck, P., A Microwave-Powered Hydrogen Lamp for Vacuum Ultraviolet Photochemical Research, Appln. Opt., Vol. 1, No. 6, p. 721.
31 McCarroll, B., An Improved Microwave Discharge Cavity for 2450 MHZ, Rev. Sci. lnstr., 41, 279, 70 p 32. Worden, E.F., Gutmacher, R.G. and Conway, .I.G., Use of Electrodeless Discharge Lamps in the Analysis of Atomic Spectra, Appl. Opt., Vol. 2, No. 7, p. 707.
33. Fehsenfeld, F.C., Evenson, K.M. and Broida, I-I.P., Microwave Discharge Cavities Operating at 2450 MHZ Rev. Sci. lnstr., Vol. 36, No. 3, p. 294.
34. Tuma, D.T., A Quiet Uniform Microwave Gas Discharge for Lasers, Rev. Sci. lnstr., Vol. 41, No. 10, p. 1519.
35. Gleason, W.S. and Pertel, R., High Stability Electrodeless Discharge Lamps, Rev. Sci. lnstr., Vol. 42, No. 11, p. 1638.
36. Dodo, Taro, et al., Electron Cyclotron Resonance Heating Device, US. Pat. No. 3,431,461, Mar. 4, 1969.
37. Omura, Itiro, et. al., Microwave Plasma Light Source, US. Pat. No. 3,541,372, Nov. 17, 1970.
This invention relates to a novel method and apparatus for efficiently generating high power ultraviolet and visible radiation with a high degree of control over the range of frequencies produced.
Sources of ultraviolet and visible radiation, having wavelengths of less than 5,000 A, are extensively used in industry for curing paints and inks, in other coating and surface treatment processes, and in the industrial synthesis of certain chemicals by photochemical reactions. Present sources of such radiation are generally limited by their low efficiencies and unwanted radiation by-products, or by their limited output powers. Existing large industrial ultraviolet sources are based on plasmas produced by DC or low frequency electrical discharges. The plasmas generated are at relatively high gas pressures (about 1 mm of mercury to about 1 atmosphere), and low plasma temperatures (about 5,000 to 10,000I(). These sources may produce several hundred watts of ultraviolet radiation but large fractions of their radiation are in the visible and infrared portions of the spectrum. The considerable power which is radiated in the visible and infrared regions represents an inefficiency for the ultraviolet source and also is often deleterious to the materials whose treatment by ultraviolet radiation is desired. Moreover, in such cool dense plasmas the electromagnetic energy is converted into kinetic energy of the atoms and ions as well as the electrons, whereas it is principally the energetic electrons which are responsible for the production of ultraviolet radiation. Hence, the kinetic energy unavoidably invested in ion and neutral atom motion represents another limitation to the efficiency of such devices as ultraviolet sources. Finally, such devices provide limited control over the frequencies of radiation produced.
Another category of commonly used ultraviolet sources operates at lower gas pressures and may be based on low frequency MHz) or microwave (-1 GHz) discharges (Refs. 2437). They operate at relatively higher electron energies and may produce ultraviolet radiation fairly efficiently, either directly by emission or through the use of fluorescent materials. However, because of the nature of the discharge plasma employed, such devices are severely restricted as to their operating power densities (i.e., the average number of watts of input electromagnetic power which can be absorbed in a given volume of plasma). This limits the total power of ultraviolet radiation that can be obtained from a source of a given size. In addition, the size and hence the power of these devices may be rigidly limited by the methods, such as resonant cavity and waveguide structures. employed for coupling microwave energy into the plasma. Furthermore, the microwave coupling structures often constrain useful viewing geometries of such devices. Because of these limitations in ultraviolet power and geometry, this class'of devices is not used extensively in industrial applications, although they are employed in analytical chemistry.
The method and apparatus disclosed herein will permit the efficient production of selected ranges of ultraviolet radiation (for example, between 1800 and 2500 Angstroms in wavelength) at high power levels which are of great importance in industrial processes such as photon induced crosslinking of polymers, free radical formation, and chemical synthesis by photochemical reactions.
Accordingly, it is an object of this invention to provide an apparatus and method for producing ultraviolet and visible radiation using a microwave generated plasma.
Another object of this invention is to provide apparatus and method for efficiently producing ultraviolet radiation at very high power densities and extracting the radiation in suitable geometric configurations.
A further object of this invention is to provide an apparatus and method for producing ultraviolet radiation in selected wavelength regions without generating comparable powers of visible and infrared radiation.
The above and other objects, advantages and distinguishing features of the invention will become apparent from the following specification, when considered with the following drawings, wherein:
FIG. 1 is a schematic block diagram illustrating the method disclosed herein,
FIG. 2 is a diagramatic structural illustration of a preferred embodiment of the invention for generating ultraviolet radiation,
FIG. 3 illustrates the location and relative intensity of the magnetic fields with respect to the heated plasma,
FIG. 4 is a diagramatic illustration of a modification of the invention incorporating power coupled to the plasma tube or vessel from two ends and a UV reflector for treating a surface or material,
FIG. 5 is a diagramatic illustration in cross section of a further modification wherein microwave power is coupled to an annular plasma tube through the center of which flows the material to be irradiated by ultraviolet light,
FIG. 6a discloses an alternative structure for coupling microwave energy with the plasma tube, and
FIG. 6b discloses a structure wherein the microwave energy is coupled radially inward to the plasma tube and allows working access to both ends of said vessel.
The present invention produces ultraviolet radiation by efficiently generating a magnetized plasma, at relatively low gas densities but high input power densities, in which the electron temperature may be varied between I0,000 and 600,000K. These highly energetic electrons subsequently collide with cooler heavy particles of the medium: atoms, molecules or ions. It is these inelastic excitation collisions and the subsequent radiative de-excitations of the heavier particles of the plasma producing medium which produce the large amounts of ultraviolet radiation. These heavy particles of the plasma producing medium include one or more of the particle species of atoms, ions and molecules. By the proper choice of operating parameters, as will be discussed below. such plasma media continuously emit up to many hundreds of Watts of ultraviolet radiation without appreciable amounts of visible and infrared radiation. Moreover, by appropriately changing the operating conditions, such as the microwave power level and/or the composition and/or pressure of the gas or gases from which the plasma is formed, the radiation can be made to be emitted elsewhwere in the spectrum from the visible to, in principle, the x-ray region. However, in the preferred practice of this invention, operation in the UV region of the spectrum is particularly preferred.
In order to clarify the description of the present invention, it is of interest to note some definitions, particularly as here employed. By plasma" is meant a partially or highly ionized gas composed of atomic or molecular particles having one or more orbital electrons removed and thus constituting ions, together with a sufficient number of free electrons to balance the electrical charge of the ions, so that the resultant plasma is subsequently electrically neutral. The plasma utilized in the present invention is generated by a technique known as collisionless transformation of waves. This term refers to the process by which the energy in electromagnetic waves (which, in the present example, represents power flowing from the microwave generator), is efficiently transferred within some region of a magnetized plasma, into electrostatic 0r longitudinal plasma waves. The energy of such plasma waves, in turn, is rapidly transferred into the kinetic energy of the plasma electrons by collective loss mechanisms such as the well-known Landau damping or collisionless absorption process. Theoretical and experimental analysis of collisionless transformation of waves indicates that the process is efficient in local regions of the plasma in which the index of refraction becomes infinite for the incident electromagnetic waves. This determines ranges of frequency w for the incident electromiC and where -Continued 2 in which definitions (u is the electron plasma frequency, defined by and a is the angle between the magnetic field and the gradient in density (and it is assumed that In these expressions, n is the number density of electrons per cubic centimeter; me and mi the electron and ion masses, respectively; e the electron charge, C the speed of light, and B the magnetic field strength. The units are CGS Gaussian.
It should be noted that if the frequency w of incident electromagnetic energy is considered as fixed, the expressions l define a range of magnetic field strengths B for which electron heating will occur. The expressions predict that as B is reduced to zero, a finite frequency range O w wpe still exists for collisionless transformation of waves. The frequency ranges defined by 1 are calculated by a somewhat simplified, or linearized theory. It is expected that nonlinear effects, such as high electromagnetic power levels, may tend to broaden the frequency range in which efficient transformation of waves may occur.
If the conditions in some region or regions of the plasma are such that the incident electromagnetic wave frequency lies in either of the regions defined by (1) above, an efficient transformation of energy from the electromagnetic waves into electrostatic or plasma waves, can occur in that region. These plasma waves, in turn, will carry the energy out of the regions and be themselves converted by collective loss porcesses such as Landau damping and other collisionless effects into energetic electrons throughout the plasma. The energetic electrons then collide with cooler heavier particles (atoms, molecules and ions), and transfer energy to their internal excitation. Finally, this energy is released in the form of deexcitati on radiation. The distribution of this radiation among the ultraviolet, visible, and other parts of the spectrum is determined by the energies of the electrons in the plasma, as well as by the types of heavy particles (atoms, ions and molecules) present.
Several features of the processes described above will be mentioned. First, the plasma heating is a collisionless process in which collective plasma behavior is responsible for converting the incident electromagnetic (microwave) energy to random kinetic energy of the electrons. This is in distinction to conventional low frequency or DC discharge lamps in which collisional heating of the gas by an electric current produces the ultraviolet emission. It is also distinguishable from nonmagnetized electrodeless discharges in which the directed energy imparted to the electrons by the electromagnetic fields is converted to kinetic energy by collisions. Thus, the present process is relatively insensitive to initial gas density or temperature. Since the present technique is not collision dependent it can also be used in plasmas which are already highly ionized where collisional methods would be ineffective. Thus unusually high power densities of incident microwave radiation can be effectively absorbed.
Second, although this process commonly makes use of a magnetic field in the plasma region, it can easily be distinguished from the more conventional electron cyclotron resonance heated (ECRH) discharges. ln these latter plasmas, the magnetic field, B, and external electromagnetic power generator must be adjusted so that the frequency, to of the incident microwaves is equal to the electron cyclotron frequency, wce in the plasma, or to a harmonic of it. In the present process, no such restrictions on w or B exist, provided the more general conditions of 1) are met. Thus, for example, lower values of magnetic field than those required by the cyclotron resonance heating condition, w=wce are sufficient for the present process, down to and including B=0. Further, the desired value of magnetic field need only be achieved over the local regions of heating, which regions have dimensions much smaller than the wavelength of the incident electromagnetic radiation (Ref. 17). These facts result in a considerable simplification in the design of a practical plasma radiation source. A third feature to be noted about the process of the present invention is that it depends geometircally only on the angle a between the magnetic field and the density gradient, but not on the direction or polarization of the incident electromagnetic waves. All three of the preceeding features are in sharp contrast to the requirements of other plasma heating techniques such as microwave cavity resonance or ECRH. These features serve to differentiate the collisionless wave transformation process and also permit flexibility in the design of a radiation source.
The manner in which the plasma heating process described above is employed to produce a unique ultraviolet source will become more clear from a consideration of a flow or operational block diagram in FIG. 1. The input electromagnetic energy, in the form of microwave radiation, is generated by a conventional source 10 such as a magnetron, and is transmitted by conventional waveguides or coaxial transmission lines to the chamber in which the plasma is to be made. The coupling of the microwave power to the gas in the plasma chamber can be accomplished by a variety of techniques and configurations.
A particularly useful configuration is shown in FIG. 2, which is a schematic of a preferred embodiment. It uses a waveguide to circular transition section 11 fitted over a tapered section 21 of the plasma tube 22. The tapered section 21 provides a region of rapidly changing plasma density in which the angle between the density gradient (i.e., the direction of maximum rate of change of density) and magnetic field can be adjusted so as to satisfy equation (1) above. This then permits efficient transformation of the microwave energy to plasma wave energy in that region. The plasma waves propagate out of that region and rapidly convert their energy into electron kinetic energy. The heated electrons then flow throughout the plasma region causing After being produced, the ultraviolet radiation passes out of the discharge tube, and by means of reflectors or lenses is directed onto the region to be irradiated. In this configuration, the ultraviolet can be emitted from the length of the discharge vessel. The intensity and spectral quality of the radiation is relatively insensitive to the gas pressure in the vessel 22, the frequency of power of the microwave radiation, or the magnitude of the magnetic field over certain ranges of these parameters. However, particular adjustments of these parameters within the allowed ranges can be employed to optimize the intensity, efficiency and spectral distribution of emitted ultraviolet radiation. The broad operating range of the device is a decided advantage over conventional methods of producing microwave plasma light sources, and in the practical utilization of such devices.
The plasma vessel 22 or tube, is usually circularly V shaped and made out of quartz or fused silica to permit the ultraviolet radiation to escape. Straight section 12 of length designated B is permitted to protrude into the rectangular to circular microwave waveguide transition section 11 having inside diameter, D, and may be any size that will fit in waveguide transition section 1 1. Straight section 12 of plasma tube 22 is followed by a conically tapered section 21 of length designated A, protruding still further into waveguide transition section 11. Conically tapered section 21 is a convenient way of providing a region of density gradient in which collisionless transformation of waves can occur. While a conical section is disclosed herein specifically, any section providing a region of density gradient in which collisionless transformations can occur can be used, including rounded tips and other shapes. In typical operation quartz tubing of 1 inch OD and 1 mm wall thickness is used as the plasma tube, and the various lengths are A=3 inches, B=6 inches, C=30 inches and diameter D=3 inches. The plasma tube is filled with a preselected gas vapor, or mixture of gases constituting the plasma forming medium and sealed off. Typical fills are gases such as air, oxygen, and xenon, mixtures such as %CO plus lO%O metal vapors such as mercury, cadmium, zinc, and antimony, and other vapors such as phosphorus and iodine. The metals may be introduced by using their inherent vapor pressure (e.g., mercury) or their high vapor pressure compounds, by using heated filaments coated with the desired metal, or by placing a small quantity of the pure metal in the tube and allowing it to be heated by a background plasma of hydrogen, helium, neon, or some other gas. In the case where a pure gas is used, the gas pressure is sufficient to sustain the microwave plasma generation, and the radiation produced ischaracteristic of the atoms, ions, or molecules present in the plasma. A mixture of gas such as CO plus 0 may be used in order to create a chemical equilibrium in the plasma which prevents material from coating the walls of the tube during operation. Another modification is to use majority gas with either a second minority gas or a metal vapor which is present in much smaller quantity, in which the minority gas or vapor is the principal source of ultraviolet radiation, and the function of the majority gas is principally to create the proper plasma conditions for excitation of the minority atoms or ions.
Typical gas fill pressures range from I to 100 millitorr for optimum performance, with limited operation possible throughout the pressure range of 10 to 5 torr. The choice of gases and pressures is determined by the spectral output that is desired. The choice of plasma tube material is primarily governed by the requirement that as much ultraviolet radiation as possible be transmitted through the tube wall in the desired spectral region. A second requirement is that the wall material exhibits minimal dielectric loss for the incident microwave energy. The plasma tube 22 may have any diameter which fits inside the circular waveguide diameter D. Large tube diameters are used in cases where the maximum ultraviolet radiation intensity (in watts per inch of lamp length) is desired.
The plasma tube is surrounded by a concentric copper mesh screen 25 or any conducting surface which acts as an extension of the circular portion of the transition section 1 l. The copper mesh waveguide extension 25 serves to prevent microwave radiation leakage outside its cylindrical volume and to redistribute that fraction of the incident microwave power which is not absorbed in the vicinity of the tapered end 21 of the plasma tube 22. This redistribution causes further microwave energy absorption along the length of the plasma tube which improves the axial uniformity of the emitted radiation. The waveguide transition section 11 is separated from the concentric screen 25 by a waveguide flange plate 26 with a hole 27 to permit the plasma tube to fit through. The size of the hole 27 and the thickness of the flange plate 26 may be varied in order to vary the distribution of microwave power between the transition section region and the remainder of the extended concentric waveguide mesh or screen. A second waveguide flange plate 28 is used to terminate the concentric screen waveguide 25. To prevent microwave radiation from escaping at that end, the hole 29 in the plate 28 must be made only slightly larger than the tube diameter and a short metal tube 30 is inserted over the discharge tube 22 and through the flange plate hole 29. Typically, this metal tube may be 1 inch ID and 2 inches long for a plasma tube of 1 inch OD. Alternatively, this tube may have any larger ID which is convenient and its end may be terminated with a metallic cap to prevent microwave leakage.
In the single ended operation as in FIG. 2, plasma tube 22 is supported by a collar clamped to the tube by set screws (not shown) at the right end and cantilevered so as to pass through the center of hole 27 in flange 26. Hole 27 is preferably much larger than the outside diameter of plasma tube 22 to permit more of the microwave energy to flow from transition section 1] to the extended, screen mesh wave guide section 25, thereby improving the axial uniformity of the emitted ultraviolet energy. The edges of hole 27 are rounded as shown to minimize electric field enhancement and re sultant arcing. In cases where the screen mesh 25 is sufficiently opaque to the incident microwave radiation, flange 26 may be entirely dispensed with by increasing the diameter of hole 27 until it equals dimension D of the transition section 11.
At microwave input power levels in excess of 200 watts certain precautions may be needed to cool the system. Water cooling coils (not shown) may be required on waveguide transition section 11, and the second waveguide flange plate 28. It is sometimes necessary to flow gas around the discharge tube 22 itself to prevent excessive heating of the quartz wall. A way of effecting this is to install a lucite, glass, or quartz shield 31, concentric with the main discharge tube 22. It may also be used to hold the mesh screen 25 in place (and in some cases the mesh may be formed or plated on the inner surface of shield 31). The shield material must be chosen to transmit the desired wavelength regions if the lamps radiation is to be used outside the shield. A gas such as nitrogen may then be flowed into the transition section 11 through the annular space between the shield 25 and the discharge tube 22 and out the second waveguide flange plate 28. The flow rate may be adjusted to provide adequate cooling. Proper choice of gas and shield material may also serve to control unwanted photochemical processes caused by the lamp. For example, nitrogen gas prevents ozone formation around the lamp. Other gases can be used to effect surface changes caused by the lamps radiation if the material to be irradiated is either placed within the shield or passed beneath an opening cut in the shield.
The electromagnetic power which excites the dis charge is produced by a conventional microwave generator 10 such as a commercial type 2450 MHz magnetron supply. Other microwave frequencies. such as 915 and l 19 MHz, and radio frequencies, such as 19 MHz (Ref. 21) may also be used. This applied electromagnetic power may be continuous or pulsed. The microwave power is transmitted to the transition section through suitable lengths of the waveguide 40 or high power coaxial waveguide. The microwave power transmitted to the discharge tube and reflected back toward the microwave generator may be monitored by power meters (not shown). For efficient coupling into the plasma, the reflected power must be minimized. For a particular set of operating conditions this is most easily accomplished by adjustment of the magnetic field. A microwave tuner (not shown) may also be used to minimize the reflected power and an isolator (not shown) may be used to limit the power reflected back toward the microwave generator.
The axial magnetic field is produced by a pair of water cooled Helmholtz coils 45 and 46 which are powered by a DC power supply (not shown). The variation of the axial magnetic field with axial position is shown in FIG. 3. The precise variation of the magnetic field is not important for the operation of the lamp, nor is the absolute magnitude of the peak magnetic field, provided only that the conditions of equation l are met in some volume. Operation at zero magnetic field is found in some cases to be possible, as predicted by equation (1). However, of the wide range of magnetic fields over which the lamp operates, the region of optimum power coupling (i.e. minimum reflected microwave power) usually occurs when, simultaneously with satisfying conditions (1), the microwave frequency is approximately equal to the electron cyclotron frequency somewhere in the lamp volume, and preferably inside the waveguide transition section. The design of the magnetic field, besides creating conditions for collisionless transformation of waves, acts to guide the heated electrons throughout the quartz plasma tube. For this reason, the peak in magnetic field, B should be in the near or to the left of the region of plasma heating R, as indicated in FIG. 3, so that the heated plasma, which tends to flow to regions of lower magnetic field, will move out into the tube 22. The magnetic field also acts to minimize the loss of electron kinetic energy to the walls of the plasma tube, thus contributing to the ability for low temperature wall operation. Other magnetic field configurations and means for producing same, such as a single turn high current helical conductor extending the length of the plasma tube may also be used. By changing the spatial structure of the magnetic field, or fields, the spatial distribution of emitted radiation from plasma tube 22 may be changed to obtain optimum radiation distribution.
In the operation of the microwave plasma ultraviolet light source, cooling water and gas flows are first turned on. The DC magnet power supply is then turned on and the magnet coils 45 and 46 are energized. The current from the power supply is adjusted to provide the desired value of axial magnetic field. Typically, the power supply will provide 350 amps (DC) at 20 volts (DC) to produce a peak magnetic field, B on axis of 1000 gauss and a minimum field of 500 gauss with two coils (45 and 46) of 24 inch separation and 19 inch mean diameter. To ionize or excite the gas in plasma tube 22, the microwave power source is activated to supply microwave radiation to the gas within the vessel by means of waveguide 40 and transition section 11. Typically, the microwave power source provides an average power output of 500 to 2000 watts at a frequency of 2450 MHz (which is a standard FCC allowed industrial frequency). In practice, the magnetic field strength may be adjusted in order to ignite the plasma tube, or a Tesla coil or other high voltage generator may be used to initiate the plasma. The microwave power levels into and reflected from the plasma tube may be measured by means of a dual directional coupler and microwave power meters (not shown). The efficiency of operation of the system can be adjusted by adjusting the position of the plasma tube in the transition section (as indicated by arrow X in FIG. 2), or by varying the magnetic field intensity or distribution, or other parameters in such a way as to minimize the reflected microwave power, measured on the power meter, and maximize the power transmitted to the plasma.
The magnetic field coils and plasma tube geometry are selected to produce the desired length and shape of ultraviolet emitting tube. Special materials may be required for the plasma tube, or for windows in it, in order to permit ultraviolet radiation to secape with minimal attenuation. Thus, for example, sapphire windows might be used to allow the emission of 1700 A radiation. The emitted radiation can be focused and directed with suitable optical equipment such as mirrors, lenses, or reflectors 60 and 65 (FIG. 4). The specific form of the auxiliary optical system would depend on the application as well as the desired wavelength. For example, a system which seeks to utilize 1800 A radiation would have to be evacuated or filled with a gas such as argon to prevent excessive absorption of the radiation by gas along the optical path, between the lamp and the material to be irradiated. Alternatively, the material could be placed within the plasma tube itself,
which thereby serves directly as a reaction vessel for ultraviolet radiation.
Although the invention has been described above with reference to a preferred embodiment, it will be apparent that other modifications may be made within the scope contemplated by the invention. For instance, the microwave generator output may be split by means of a power divider 61 (FIG. 4) and the power fed into the discharge tube from waveguide transition sections 62, 63 at both ends of the tube 22. This would tend to provide a more uniform ultraviolet emission from a long plasma tube. Such a modification is shown schematically in FIG. 4 where a UV reflector 60 is also shown to illustrate one way of concentrating the ultra-violet energy on a surface to be irradiated. The reflector may also be constructed by depositing a coating of high UV reflectivity on the inside of the screen waveguide 25 around roughly half of its circumference. Another way is to use a lens system 65.
A further modification utilizing microwave power coupled in from two ends 76, 77 of a microwave chamber 74 is shown in FIG. 5. It is applicable to a large annular plasma vessel which is useful for photochemical applications. the material to be irradiated would be caused to pass or flow along the axis of the inner annular vessel 72, typically of quartz, and thereby would be surrounded by ultraviolet emitting plasma. The outside or outer vessel 78 could have a coating of high UV reflectivity material on its outer surface, or the inner surface of the microwave chamber 74 could carry the reflective coating. In the embodiment shown in FIG. 5 the ends 70 and 71 of the plasma vessel are tapered to replace full conical sections. The embodiment of FIG. 5 includes metallic tubes 79 of length l and inside diameter d at both ends of the microwave chamber. The as pect ratio l/d must be sufficiently large and d sufficiently small compared to the microwave wavelength that no appreciable amounts of microwave energy leak out of the cavity.
As a final example, other techniques may be employed for coupling the microwave energy into the plasma vessel. One particular technique involves the use of a rectangular waveguide section 80 directly, as shown in FIG. 6a. In this approach a standard section of rectangular waveguide is terminated (capped) at one end and a circular hole is cut to accept the plasma tube. A limitation to this approach is that the tube diameter cannot exceed the minimum waveguide dimension, )1. A further advantageous microwave coupling technique uses an axially or helically slotted slow wave structure which fits directly over the plasma tube such as the one illustrated in FIG. 6b and described in detail in references 22 and 23. In this case, a shielded coaxial cable 86 is used to convey microwave energy to the slotted coil 85. Alternatively, a waveguide, properly terminated may be used to couple energy to slotted coil 85. For low frequency electromagnetic input radiation (2-200 MHz), a simple antenna such as a single turn copper strap (Ref. 21) can be used to couple to the plasma tube. For these elctromagnetic coupling schemes and others, such as that shown in FIG. 5, which do not requiretermination of the plasma vessel at its end, the plasma vessel may be bent around and joined one end upon the other to form a closed ring or toroid.
The invention herein described is to be construed to be limited only by the prior art when considered by the spirit and scope of the appended claims.
What is claimed is:
l. A microwave generated light source for both producing and emitting light in the visible to ultraviolet region along a substantial length of a longitudinally extending plasma forming medium containing envelope, comprising; a sealed, longitudinally extending plasma forming medium containing envelope, means for exciting said plasma forming medium in said envelope to generate a plasma and produce said light, said means for exciting including:
1. means for generating microwave energy, and
2. microwave chamber means for coupling said generated microwave energy to said plasma forming medium, a part of said chamber means extending in the longitudinal direction of said envelope and surrounding said envelope at least along a substantial portion of the length of the envelope, and at least part of said chamber means being made of a metallic mesh whereby said microwave energy is retained in said chamber means while said light produced along a length of said envelope is emitted out of said chamber means through said mesh.
2. The light source of claim 1 wherein said mesh is made of copper.
3. The light source of claim 1 wherein said mesh is surrounded by a shield of solid, ultraviolet and visible transmissive material to prevent cooling gas which may be circulated around said envelope in the vicinity of said mesh from escaping.
4. The light source of claim 1 wherein said medium is of the type which may be collisionlessly excited and said means for exciting comprises means for collisionlessly exciting said medium.
5. The light source of claim 4 wherein said envelope is tapered at each longitudinal end thereof, further including microwave energy dividing means for dividing said generated microwave energy into two parts, said chamber means coupling each part to a respective longitudinal end of said envelope.
|Brevet cité
|Date de dépôt
|Date de publication
|29 juin 1962
|11 avr. 1967
|Max Planck Gesellschaft
|Device for producing electro-magnetic oscillations of very high frequency
|4 nov. 1964
|9 janv. 1968
|Sperry Rand Corp
|Electron beam-plasma device operating at multiple harmonics of beam cyclotron frequency
|12 févr. 1965
|19 mars 1968
|Melpar Inc
|Intense incoherent light source obtained by quenching the higher excited states and concentrating the energy on the lower states
|2 janv. 1964
|16 avr. 1968
|Rca Corp
|Fast wave transmission line coupled to a plasma
|21 déc. 1967
|17 nov. 1970
|Hitachi Ltd
|Microwave plasma light source
|7 mai 1969
|4 mai 1971
|Vladimir Pavlovich Kirjushin
|Microwave plasmatron
|14 janv. 1970
|28 sept. 1971
|Varian Associates
|High-power plasma generator employed as a source of light flux at atmospheric pressure
|5 nov. 1969
|8 févr. 1972
|Varian Associates
|High-power microwave excited plasma discharge lamp
|6 nov. 1970
|16 mai 1972
|Giuseppe Lisitano
|Radio-frequency plasma generator
|Brevet citant
|Date de dépôt
|Date de publication
|16 mars 1979
|5 mai 1981
|Gte Laboratories Incorporated
|Electromagnetic discharge apparatus with double-ended power coupling
|15 juil. 1981
|16 nov. 1982
|Fusion Systems Corporation
|Method and apparatus for igniting electrodeless discharge lamp
|26 juin 1980
|8 nov. 1983
|Deutsche Forschungs- Und Versuchsanstalt Fur Luft-Und Raumfahrt E.V.
|Apparatus for producing a discharge in a supersonic gas flow
|2 juil. 1984
|5 févr. 1985
|Mitsubishi Denki Kabushiki Kaisha
|Microwave generated plasma light source apparatus
|24 mai 1982
|26 mars 1985
|Fusion Systems Corporation
|Microwave generated electrodeless lamp for producing bright output
|29 nov. 1982
|4 juin 1985
|Leybold-Heraeus Gmbh
|Apparatus for producing a microwave plasma for the treatment of substrates, in particular for the plasma-polymerization of monomers thereon
|30 avr. 1984
|11 mars 1986
|Rca Corporation
|Deep ultraviolet (DUV) flood exposure system
|6 avr. 1984
|29 avr. 1986
|Zimmerman S Mort
|Electromagnetic radio frequency excited explosion proof lighting method and system
|30 avr. 1984
|25 nov. 1986
|Rca Corporation
|Deep ultraviolet (DUV) flood exposure system
|2 oct. 1984
|24 févr. 1987
|L'Air Liquide, Societe Anomyme pour l'Etude et l'Exploitation des Procedes Georges Claude
|Hyperfrequency energy plasma torch
|26 févr. 1985
|16 juin 1987
|Mitsubishi Denki Kabushiki Kaisha
|Microwave discharge light source apparatus
|4 déc. 1985
|1 mars 1988
|Wertheimer Michael R
|Apparatus and method for plasma treatment of substrates
|18 juin 1985
|7 juin 1988
|Mitsubishi Denki Kabushiki Kaisha
|Illuminator for cultivating plant
|10 déc. 1985
|20 déc. 1988
|The United States Of America As Represented By The Department Of Energy
|Instantaneous and efficient surface wave excitation of a low pressure gas or gases
|23 juil. 1985
|14 mars 1989
|Fusion Systems Corporation
|Optical system for uniform illumination of a plane surface
|14 sept. 1988
|26 juin 1990
|The Regents Of The University Of California
|Method of accelerating photons by a relativistic plasma wave
|23 mai 1989
|3 juil. 1990
|Leybold Aktiengesellschaft
|Apparatus for producing a plasma and for the treatment of substrates
|9 févr. 1989
|15 janv. 1991
|Idemitsu Petrochemical Co., Ltd.
|Method for synthesis of diamond
|24 mai 1988
|5 févr. 1991
|National Institute For Research In Inorganic Materials
|Apparatus for synthesizing diamond
|3 oct. 1989
|5 févr. 1991
|Osamu Uesaki
|Ultra violet rays generator by means of microwave excitation
|6 avr. 1990
|13 aoűt 1991
|New Japan Radio Co., Ltd.
|Electrodeless microwave-generated radiation apparatus
|5 mars 1990
|22 oct. 1991
|Societe Anonyme : Societe Prolabo
|Apparatus for chemical reaction by wet process comprising a stack equipped with a barrier against the propagation of microwaves
|15 mai 1990
|3 déc. 1991
|Gte Laboratories Incorporated
|Electrodless hid lamp with microwave power coupler
|15 mai 1990
|12 mai 1992
|Gte Laboratories Incorporated
|Electrodeless HID lamp with lamp capsule
|7 avr. 1988
|28 juil. 1992
|Hi Tachi, Ltd.
|Plasma generating apparatus
|11 avr. 1991
|1 sept. 1992
|Ultraviolet Energy Generators, Inc.
|Method for destruction of toxic substances with ultraviolet radiation
|4 oct. 1991
|24 nov. 1992
|Le Vay Thurston C
|Microwave-actuated ultraviolet sterilizer
|22 sept. 1992
|29 mars 1994
|Online Energy, Inc.
|Ultraviolet flash dryer
|12 nov. 1992
|6 sept. 1994
|Dimotech Ltd.
|Apparatus for the treatment of skin wounds
|12 mars 1992
|1 nov. 1994
|Fusion Systems Corp.
|Microwave discharge device with TMNMO cavity
|28 déc. 1993
|28 nov. 1995
|E. I. Du Pont De Nemours And Company
|Apparatus and process for the preparation of hydrogen cyanide
|27 janv. 1993
|2 avr. 1996
|Fusion Systems Corporation
|Excimer lamp with high pressure fill
|24 oct. 1994
|26 nov. 1996
|United Kingdom Atomic Energy Authority
|Plasma light source
|7 juin 1995
|25 mars 1997
|R Squared Holding, Inc.
|Electrodeless sterilizer using ultraviolet and/or ozone
|2 avr. 1996
|9 sept. 1997
|Daniylchev; Vladimir A.
|Microwave powered ozone producing system
|25 mars 1996
|11 nov. 1997
|Fusion Uv Systems, Inc.
|Excimer lamp with high pressure fill
|7 juin 1995
|8 sept. 1998
|Fusion Lighting, Inc.
|Lamp with controllable spectral output
|1 févr. 1996
|6 oct. 1998
|Osram Sylvania Inc.
|Electrodeless high intensity discharge lamp having a phosphorus fill
|7 avr. 1995
|20 oct. 1998
|Gabor; George
|RF driven sulfur lamp having driving electrodes arranged to cool the lamp
|7 avr. 1994
|22 juin 1999
|The Regents Of The University Of California
|RF driven sulfur lamp having driving electrodes which face each other
|3 sept. 1997
|3 aoűt 1999
|Danilychev; Vladimir A.
|Energy efficient ultraviolet visible light source
|23 janv. 1997
|2 nov. 1999
|Fusion Lighting, Inc.
|Inductive tuners for microwave driven discharge lamps
|23 mai 1997
|9 nov. 1999
|The Regents Of The University Of California
|Isotope separation using a high field source and improved collectors
|5 mars 1999
|29 aoűt 2000
|Semiconductor Energy Laboratory Co., Ltd.
|Method for forming a film
|30 sept. 1998
|27 mars 2001
|Kimberly-Clark Corporation
|Elastic nonwoven webs and films
|20 nov. 1998
|17 avr. 2001
|Semiconductor Energy Laboratory Co., Ltd.
|Plasma processing apparatus and method
|12 aoűt 1998
|26 mars 2002
|Massachusetts Institute Of Technology
|Very high power microwave-induced plasma
|20 nov. 1998
|23 juil. 2002
|Semiconductor Energy Laboratory Co., Ltd.
|Plasma processing apparatus and method
|30 sept. 1998
|4 mars 2003
|Kimberly-Clark Worldwide, Inc.
|Crimped polymeric fibers and nonwoven webs made therefrom with improved resiliency
|26 juil. 2000
|26 aoűt 2003
|Quay Technologies Ltd.
|UV light source
|12 avr. 2002
|14 oct. 2003
|Lg Electronics Inc.
|Cooling system of lighting apparatus using microwave energy
|10 aoűt 2000
|9 déc. 2003
|Semiconductor Energy Laboratory Co., Ltd.
|Pulsed electromagnetic energy method for forming a film
|6 juin 1995
|13 janv. 2004
|Semiconductor Energy Laboratory Co., Ltd.
|Microwave enhanced CVD method and apparatus
|3 févr. 2003
|3 aoűt 2004
|Xtreme Technologies Gmbh
|Method for generating extreme ultraviolet radiation based on a radiation-emitting plasma
|8 juil. 2002
|4 janv. 2005
|Semiconductor Energy Laboratory Co., Ltd.
|Method for forming I-carbon film
|7 oct. 2003
|11 janv. 2005
|Miltec Corporation
|Snap-in radio frequency screen for ultraviolet lamp system
|16 avr. 2004
|13 juin 2006
|Sungkyunkwan University
|Neutral beam source having electromagnet used for etching semiconductor device
|20 aoűt 2002
|25 juil. 2006
|Quay Technologies Limited
|Pulsed UV light source
|8 déc. 2003
|24 oct. 2006
|Semiconductor Energy Laboratory Co., Ltd.
|Pulsed plasma CVD method for forming a film
|19 janv. 2005
|31 oct. 2006
|Lg Electronics Inc.
|Middle output electrodeless lighting system
|22 févr. 2005
|20 févr. 2007
|The United States Of America As Represented By The United States Department Of Energy
|Method for plasma formation for extreme ultraviolet lithography-theta pinch
|15 sept. 2000
|9 déc. 2008
|Nordson Corporation
|Apparatus and method for generating ultraviolet radiation
|19 oct. 2004
|28 juil. 2009
|Jenact Limited
|UV light source
|16 sept. 2005
|20 juil. 2010
|Jenact Limited
|Sterilisation of duct flows
|24 sept. 2007
|14 sept. 2010
|Severn Trent Water Purification, Inc.
|8 déc. 2008
|12 avr. 2011
|Amarante Technologies, Inc.
|Plasma generating nozzle having impedance control mechanism
|3 oct. 2008
|12 avr. 2011
|Nordson Corporation
|Ultraviolet curing apparatus for continuous material
|13 févr. 2007
|12 juil. 2011
|Saian Corporation
|Plasma generation apparatus and work processing apparatus
|13 nov. 2008
|27 sept. 2011
|Jenact Limited
|Methods and apparatus for generating ultraviolet light
|7 juil. 2005
|11 oct. 2011
|Amarante Technologies, Inc.
|Microwave plasma nozzle with enhanced plume stability and heating efficiency
|17 mars 2006
|10 juil. 2012
|Wms Gaming Inc.
|Wagering games with unlockable bonus rounds
|10 sept. 2010
|18 sept. 2012
|Severn Trent Water Purification, Inc.
|Method and system for achieving optimal UV water disinfection
|9 sept. 2011
|23 avr. 2013
|Vela Technologies, Inc.
|Integrating optical systems and methods
|16 déc. 2009
|7 oct. 2014
|Vela Technologies, Inc.
|Integrating optical system and methods
|11 févr. 2015
|2 févr. 2016
|Gaming device having a selectively accessible bonus scheme
|26 janv. 2016
|10 janv. 2017
|Gaming device having a selectively accessible bonus scheme
|28 sept. 2015
|28 mars 2017
|Energetiq Technology, Inc.
|Laser-driven light source for generating light from a plasma in an pressurized chamber
|4 févr. 2002
|28 nov. 2002
|Purepulse Technologies, Inc.
|Inactivation of microbes in biological fluids
|8 juil. 2002
|30 janv. 2003
|Semiconductor Energy Laboratory Co., Ltd.
|Plasma processing apparatus and method
|3 févr. 2003
|7 aoűt 2003
|Xtreme Technologies Gmbh
|Method for generating extreme ultraviolet radiation based on a radiation-emitting plasma
|8 déc. 2003
|17 juin 2004
|Semiconductor Energy Laboratory Co., Ltd.
|Method for forming a film
|20 aoűt 2002
|25 nov. 2004
|Moruzzi James Lodovico
|Pulsed uv light source
|16 avr. 2004
|8 sept. 2005
|Sungkyunkwan University
|Neutral beam source having electromagnet used for etching semiconductor device
|11 avr. 2005
|8 sept. 2005
|Semiconductor Energy Laboratory Co., Ltd.
|Microwave enhanced CVD method and apparatus
|19 oct. 2004
|1 déc. 2005
|Jenact Limited
|UV light source
|19 janv. 2005
|13 avr. 2006
|Lg Electronics Inc.
|Middle output electrodeless lighting system
|13 févr. 2007
|23 aoűt 2007
|Noritsu Koki Co., Ltd.
|Plasma generation apparatus and work processing apparatus
|28 avr. 2005
|29 nov. 2007
|Pascal Sortais
|Light Source with Electron Cyclotron Resonance
|2 aoűt 2005
|20 déc. 2007
|Lee Sang H
|System and Method for Optimizing Data Acquisition of Plasma Using a Feedback Control Module
|7 juil. 2005
|24 janv. 2008
|Amarante Technologies, Inc.
|Microwave Plasma Nozzle With Enhanced Plume Stability And Heating Efficiency
|24 sept. 2007
|5 juin 2008
|James Lucas
|13 nov. 2008
|21 mai 2009
|Jenact Limited
|Methods and apparatus for generating ultraviolet light
|12 nov. 2008
|25 mars 2010
|Sang Hun Lee
|Plasma generating system having tunable plasma nozzle
|3 oct. 2008
|8 avr. 2010
|Nordson Corporation
|Ultraviolet curing apparatus for continuous material
|8 déc. 2008
|10 juin 2010
|Sang Hun Lee
|Plasma generating nozzle having impedance control mechanism
|9 févr. 2009
|12 aoűt 2010
|Sang Hun Lee
|Plasma generating system having nozzle with electrical biasing
|21 avr. 2009
|7 oct. 2010
|Sang Hun Lee
|Method of sterilization using plasma generated sterilant gas
|16 déc. 2009
|12 mai 2011
|Vela Technologies, Inc.
|Integrating Optical System and Methods
|13 nov. 2009
|20 oct. 2011
|Achille Zanzucchi Editore Di Achille Zanzucchi
|Static electromagnetic apparatus for accelerating electrically neutral molecules utilizing their dipolar electric moment
|18 févr. 2014
|21 aoűt 2014
|Sumitomo Heavy Industries, Ltd.
|Microwave ion source and method for starting same
|20 nov. 1986
|22 mars 1988
|Mitsubishi Denki Kabushiki Kaisha
|Microwave generated plasma light source apparatus
|4 mars 2005
|14 oct. 2009
|Middle output electrodeless lighting system
|30 juin 1983
|5 janv. 1984
|Fusion Systems Corp
|Elektrodenlose lampe und dafuer vorgesehenes lampengehaeuse
|28 févr. 1997
|3 sept. 1998
|Umex Ges Fuer Umweltberatung U
|Electrodeless ultraviolet gas discharge lamp excited by high frequency oscillator
|6 juil. 2007
|15 janv. 2009
|Eastman Kodak Co.
|Radiation source for fixing UV-crosslinkable toners on a printing material comprises a low-pressure gas discharge lamp containing a gas emitting in the UV spectrum and a microwave application unit with two separate microwave applicators
|6 juil. 2007
|21 juin 2012
|Eastman Kodak Co.
|6 juil. 2007
|19 mars 2009
|Eastman Kodak Co.
|Microwave stimulated-radiation source for use in printing medium fixing device, has segments positioned on different areas of lamp body, where microwave power output of one segment is adjusted independent of other segment
|17 aoűt 1987
|31 aoűt 1988
|Leybold Aktiengesellschaft
|Device for producing a plasma and for treating substrates in said plasma
|17 aoűt 1987
|5 mai 1993
|Leybold Aktiengesellschaft
|Device for producing a plasma and for treating substrates in said plasma
|13 mai 1991
|21 nov. 1991
|Osram Sylvania Inc.
|Electrodeless HID lamp with microwave power coupler
|1 juin 1991
|16 déc. 1992
|Heraeus Noblelight GmbH
|Irradiation device with a high power radiator
|22 déc. 2000
|4 déc. 2002
|Fusion Uv Systems, Inc.
|Lamp with self-constricting plasma light source
|22 déc. 2000
|10 sept. 2003
|Fusion Uv Sys Inc
|Lamp with self-constricting plasma light source
|5 janv. 2005
|26 juil. 2006
|Lg Electronics Inc.
|Middle output electrodeless lighting system
|4 mars 1994
|15 sept. 1994
|Universite Des Sciences Et Technologies De Lille
|Plasma production device
|7 juin 1996
|19 déc. 1996
|R Squared Holding, Inc.
|Electrodeless sterilizer using ultraviolet and/or ozone
|23 nov. 1999
|8 juin 2000
|Quay Technologies Ltd
|26 juil. 2000
|8 févr. 2001
|Quay Technologies Limited
|Uv light source
|28 avr. 2005
|8 déc. 2005
|Pascal Sortais
|Light source with electron cyclotron resonance
|31 mars 2006
|14 déc. 2006
|Xavier Pellet
|Microwave device for treating a flux with visible radiation
|12 sept. 2006
|5 avr. 2007
|Robert Chrysler Brennan, Trustee For Sdi Technology Trust
|System, apparatus, and method for increasing particle density and energy by creating a controlled plasma environment into a gaseous media
|12 sept. 2006
|11 oct. 2007
|Robert Chrysler Brennan
|System, apparatus, and method for increasing particle density and energy by creating a controlled plasma environment into a gaseous media
|14 mars 2014
|18 sept. 2014
|Consiglio Nazionale Delle Ricerche
|Packed microwave powered lamp
|Classification aux États-Unis
|Classification internationale
|Classification coopérative
|Classification européenne


text:
More Optics. More Technology. More Service.
Edmund Optics® has been a leading supplier of optics and optical components to industry since 1942, designing and manufacturing a wide array of multi-element lenses, lens coatings, imaging systems, and optomechanical equipment. Led by a staff of skilled optical engineers and scientists, EO is application focused and pursues new ways to implement optical technology,enabling advancements in the life sciences, semiconductor manufacturing, industrial metrology, and medical instrumentation. EO's precision optical components improve efficiencies & yields and are used in test & measurement, quality assurance applications, the automation of manufacturing process, and cutting-edge research.
Originally a supplier of optics and other science items for hobbyists and education use, EO refocused on industrial optics during the mid-1980s and has earned the ranking of preferred supplier of optical components, according to Readex Research, for the past 9 years.
You may know Edmund Optics for our catalog of industrial optics, but that is only a part of the services EO offers.
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With over 193,000 sq. ft. of dedicated manufacturing space, two world-class design centers, and global sales locations in US, UK, Germany, France, Finland, Singapore, China, Japan, Korea and Taiwan; Edmund Optics is ready to take your next project from design to prototype to volume production!
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subset: commoncrawl


text:
A former executive at Swiss bank UBS wanted in America for allegedly helping wealthy US citizens dodge tax has been arrested in Italy.
Police in Bologna said that over they weekend they apprehended Raoul Weil, who was declared a fugitive in early 2009 by US authorities.
American regulators wanted to question Mr Weil when the former head of UBS's wealth management business failed to surrender to authorities on charges he conspired to help 17,000 Americans hide assets worth $20bn (£12.4bn) in Swiss bank accounts.
That year, UBS was fined $780m and agreed to hand over the names of about more than 4,000 American clients with secret Swiss bank accounts to avoid facing criminal charges. The deal with the US marked an historic break with Switzerland's tradition of bank secrecy.
A spokesman for the Bologna police said on Monday the arrest of the former banker had taken place on Saturday morning and she did not know whether he was still in the prison where police had taken him.
"Mr Weil checked into a Bologna hotel and this set off an alert system because there is an international arrest warrant for him coming from the US," the spokesman said.
News agencies were not immediately able to contact Mr Weil or a legal representative for him.
When Mr Weil was indicted in November 2008, his attorney said he was innocent and called the charges against him "totally unjustified."
A UBS spokesman said on Monday that Mr Weil was discharged from this duties at the bank when he was indicted.
UBS's 2009 fine was followed this year with a deal between the Swiss and US governments allowing some other Swiss banks to pay fines to avoid or defer prosecution over tax evasion by their US customers.
Edited by Alan Tovey


text:
I work With This, Part 3
Greg Delange's new name is,' Mr.McSneaky pinky stinky head'
Greg Delange's new name is,' Mr.McSneaky pinky stinky head'
Yes, it is a fact, Greg and I are back doing mornings on KORD-FM. Faith is now doing the news, and Big Bear will move to afternoons. All of this for me means waking up to an alarm clock once again. Don't get me wrong, it is exciting to be back in the am, but the am is so early.
Are you one of those that has to have a stick of dynamite to get you out of bed in the morning or do you jump out of bed at 4am and exercise and do all your housework before you go to work? Curious minds want to know!
Hey Everybody!! Today is our first day as the new team for MORNINGS on KORD!
Thank you for keeping us company as we begin our "work in progress" We appreciate you listening...


text:
Franco German reconciliation hailed as EU receives Nobel Peace Prize
With most of Europe's leaders in attendance, the Nobel committee presented its Peace Prize to the Union today, praising its "dramatic" feat in turning a continent of war into a haven of peace for the past 60 years.
Seated side by side, Angela Merkel, the German Chancellor, and President Hollande of France nodded in agreement as Thorbjoern Jagland, chairman of the Norwegian committee, hailed the postwar Franco-German reconciliation and the subsequent European Community as an achievement that fully deserved the world's leading peace prize.
Europe had been transformed from "continent of war" into a "continent of peace", Mr Jagland told about 20 EU leaders and other dignitaries in the Oslo city hall. "That should not be taken for granted - we have to struggle for it…


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While a few romantic comedies in the past few years have broken from traditional plot structure and shined, there's hardly been any worthwhile romantic dramas. Both sides of the romance genre seem to always follow the same trail from point A to point B; the two leads fall for one another, things are great, they fight, they get back together in the last reel. This constant travel through familiarity makes rare gems like Wong Kar-Wai's "In The Mood For Love" even more special and enjoyable.
The film revolves around Mrs. Chan (Maggie Cheung) and Mr. Chow (Tony Leung). As the film begins, the two have moved into the same apartment building as each other and find that they are next-door neighbors. She is a secretary, while he is a reporter who has the desire to write martial arts stories. Both of their significant others are often travelling, so they are hardly seen by the characters and, at least through this story, are never really seen by us.
Given that the two are neighbors and seem like relatively nice people, they find themselves spending time with one another, simply having dinner or talking. Yet, even in the simplest scenes, there are great little moments. Chow puts a little bit of sauce on Mrs. Chan's plate and she tastes it. The camera focuses on these little moments in a way that isn't overly distinct, pushing the audience to acknowledge the possibility that the two have feelings for one another; the camerawork throughout this film does a wonderful job naturally highllighting gestures, movements and other elements.
After the two learn that their spouses are having an affair, the bond between them deepens, but will they act upon their feelings? The performances by both Cheung and Leung couldn't have been any better. There were several scenes that I could have listened to without words, as their faces did a perfect job of conveying their emotion. This is certainly one of those films where a simple glance seems to speak volumes. The look of the film has also been delicately crafted down to the slightest detail; the film's beautiful color palette, detailed sets and strong costumes give the film a wonderful texture, feel and overall appearance. The cinematography by both Christopher Doyle and Mark Lee Ping-bin often creates some of the most gorgeous, postcard-perfect imagery that I've seen in film recently. The film's 98 minutes even pass by quickly, mainly because I found the performances and story so engaging.
"In The Mood For Love" is a phenomenal picture; a marvelously acted tale of longing that is moving and often stunning in appearance. It's definitely a must-see.
The DVD
VIDEO: Criterion presents "In The Mood For Love" in 1.66:1 anamorphic widescreen, the new digital transfer made from a 35mm interpositive. Criterion's new edition looks positively beautiful and is a remarkable presentation of Christopher Doyle and Mark Lee Ping-bin's stunning and rich cinematography. The image remains wonderfully detailed and sharp throughout, with a smooth, "film-like" quality that's highly pleasing.
As for flaws with the image, I had a difficult time finding any at all. Another non-Criterion DVD edition that I browsed through contained its fair share of various print flaws. The Criterion edition, on the other hand, remains completely free of such irritants - the print was completely flawless; no scratches, dirt or specks. Furthermore, there's not even any instances of edge enhancement or pixelation for a completely natural-looking and crystal clear image.
Colors remained beautiful throughout the picture; the film's rich, attractive color palette appeared well-saturated, vivid and rich with no smearing or other flaws. Black level appeared solid, while flesh tones remained accurate. This is really a fantastic effort from Criterion that deserves high praise.
SOUND: "In The Mood For Love" is presented by Criterion in Dolby Digital 5.0, as it was in theaters. While the film is almost entirely dialogue-driven, I still found a lot to appreciate with the sound mix. The audio, as expected, remains rather front heavy, but also presents a strong amount of detail, such as background sounds and other elements clearly. The surrounds are understandably not given a great deal to do, aside from offer Michael Galasso's haunting score, which perfectly compliments the on-screen events. The rainy sequences also provide very enveloping and natural sounds of rain. Dialogue seemed to be clear and natural, as well. A very enjoyable soundtrack that, while not agressive, does work quite wonderfully for the movie. An additional isolated score track is available in Dolby 2.0
MENUS: Slightly animated main menu with score in the background. There's also some beautiful little transitions between menus. Appropriate for the movie.
EXTRAS:: The majority of the supplements are included on the second disc, but the first disc does have some supplements. Four deleted scenes are included, three of which have optional commentary from the director (the commentary is provided in English Subtitles). An interactive essay about the film's music, as well a note from the composer and director, are also included in a second called, understandably, "About The Music". Last, but certainly not least, a short film by the director called "Hua Yang De Nian Hua" is included.
@ In The Mood For Love: This is a 51-minute documentary that gives the viewer a complete look at the making of this picture. Through interviews and behind-the-scenes footage, we are allowed a look at how the film came together through the production and through the promotion. The interviews were insightful and enjoyable and the behind-the-scenes footage was enjoyable, but there occasionally seemed to be a lot of film footage in-between. The documentary is presented in Cantonese with English subtitles.
Toronto Film Fest Coverage: This is a program that offers the confrence at the festival featuring the two lead actors from the film, both of whom do speak English during this program as they respond to the questions offered by the moderator and the audience. The questions are quite good and I enjoyed hearing the responses from the two leads. This program lasts 43 minutes.
Promotional Material: This section includes both unused artwork and posters as well as the posters for the film's release and a very good 18-minute "making of" documentary (the documentary is listed as "electronic press kit"). Also included here are two Hong Kong TV spots, a US TV spot and trailer as well as a French TV Spot and trailer.
Interviews with Wong Kar-Wai: There are two interviews included in this section, one is a "Cinema Lesson" that was hosted at the Cannes Film Fest by Giles Ciment and the other is a 22-minute interview with the director and film critics Michael Ciment and Hubert Niogret. Both documentaries combined really form a good overview of Wong Kar-Wai's filmmaking style and concepts about storytelling.
Also: Cast/crew bios, a look at Wong Kar-Wai's career, essay about "In The Mood For Love" and photo gallery.
Booklet: A larger booklet than usual for a Criterion release; it contains a 46-page short story that influenced the film as well as notes about the transfer, credits and an essay.
Final Thoughts: "In The Mood For Love" is a fantastic picture with two great lead performances, beautiful cinematography and many other positive aspects to recommend it. Criterion's two-disc set is terrific, offering very good audio/video and a wealth of supplements about this great film. A must-see.


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Photographer's Note
The Superstition Mountains, popularly called "The Superstitions", are a range of mountains in Arizona located to the east of the Phoenix metropolitan area. They are anchored by Superstition Mountain, a large mountain that is a popular recreation destination for residents of the Phoenix, Arizona area.
As with most of the terrain surrounding the Phoenix metropolitan area, the Superstition Mountains have a desert climate, with high summer temperatures and a handful of perennial sources of water.
Some Apaches believe that the hole leading down into the lower world is located in the Superstition Mountains. Winds blowing from the hole are supposed to be the cause of severe dust storms.
Critiques | Translate
kiks (12785) 2012-08-23 8:41
Hello Janson, never seen before this imposant montains. Thanks. I like the composition showing well the diferent rock formations. At my screen the colors are a bit grey. Personaly i would like to see a more warm tint.But it kan be that the colors are naturaly like this.
Realy intersting note.
Best regadrs
jemaflor (108461) 2012-08-25 2:28
Hi Jason,
Impressive mineral landscape with these cliffs, well presented with a vertical format, good light capture.
ikeharel (84968) 2012-08-25 9:01
Hello Jason,
Magnificent rocks on the unique eart formation shown.
Excelent clarity, light and depth collected.
Beeing superstitious on the desert, is not a good idea - one must be alert and with all senses stimulanted - to grasp the beauty and to be careful from all sort of dangers out there.
Beautiful and impressive taken shot.
No_One (4) 2013-04-02 8:31
hi Jason,
Great shot of these very monumental mountains, and what a cool name too. Looks like true Road Runner country here. If thats the case, no wonder they are claled superstition mountains, there is always a good chance there is a coyote about to drop an anvil on your head!
Thanks for sharing
kordinator (15453) 2013-07-07 0:50
Hello Jason
An impressive setting for this rock.
Great details.
Fantastic vivid colors and perfect lighting.
Excellent job.
Kind regards
serp2000 (46526) 2014-05-01 1:18
Hi, Jason,
Only one word "Apache" brings me back to my childhood. Oh how I loved the western movies and books! And this photo looks like a scanned photo from pre-digital times. Attractive view, but I'd like to add the American indeans or cowboys for effect. ;)
Best wishes,
fritzi007 (13546) 2014-06-11 13:01
Hello Jason,
interesting photo, perfect photo quality and very good comment, congratulate!
Best wishes
Photo Information
- Copyright: Jason Cowling (jcpix) (14024)
- Genre: Places
- Medium: Color
- Date Taken: 2010-03-00
- Categories: Nature
- Photo Version: Original Version
- Date Submitted: 2012-08-22 15:27


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In this post, we look at one type of Easter postcard published by Paul Finkenrath Berlin, also known as PFB. All the postcards published by PFB show good artwork and fine printing, and there are some dramatic Easter designs with simple designs set against dark backgrounds that really make the images extra-vivid. However, this post focuses on the elaborate detailed designs that show off PFB's fine printing capability. We open with a fantasy image of a child driving a lamb-drawn Easter egg cart through a country scene. Not only does the meadow have subtle color gradations of grass, earth and flowers, but the sky is a glorious soft aqua blue with fantastic realistic clouds floating above our image. PFB's clouds are spectacular - some lit with delicate sun ray colors and some shadowed with soft pastel grey. The embossing on these postcards is just as superb, featuring fine detail rarely found from other publishers.
Above, a little girl leads her sheep down a country path, pulling a flower-decorated cart with a huge coral-colored egg. The child's white dress is not only embossed, but also embellished with tiny gold decorations.
Fantasy images for Easter from PFB often include children with huge eggs; in the postcard below, two children are seated inside a big pink egg, accompanied by a curious lamb. Note the pink clouds and the unusually complex detail in the tree leaves and branches.
Even the floral garlands have beautifully drawn leaves and flowers.
Here is an image of a little girl - once again dressed in European country garb like the children in the pink egg. This time she is shown with a silver surround, the main image in a sunrise oval vignette. She carries a lamb on her shoulders and pink blossoms provide a colorful Spring touch at the bottom of the egg-shaped image. The colors nearly 'glow.'
These children have found a huge egg that brother carries and a huge rooster to match...the scale is a little startling as the rooster is actually larger than little sister who is seated in a rustic wooden cart. Brother is either hailing or teasing the rooster. Still, the general air is cheerful!
The sky in the pretty image above is an unusual deep turquoise with ragged rose pink clouds. The children wear country garb, standing beside some fantastically big pussy willow stems. Their lamb stands with them. Note the detail in the wooden gate and in the greenery at their feet.
The last example of PFB Easter designs in this post is one of our favorites, from a series of children in bird's nests. In this image, the children are singing beneath the pastel pink flowering branches of a tree with birds joining in the Easter chorus. Exquisite details, rich embossing and superior artistry light up this design.
Price Estimates: PFB postcards vary in price depending on rarity, condition, design and where you find them. There are quite a lot of PFB postcards available, so they must have been popular when they were first published. The Easter postcards shown in this post range in price from about $10 - $20. They are often more expensive at postcard shows. Sometimes you can find them in lots, which reduces the price per card. These estimates are for postcards in EXCELLENT condition (a couple of our illustrations in this post have cancellation marks on the front which reduces the value) and they are only estimates.


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Alicia Silverstone's racy new shoot in Bullet magazine.
Here are some background information about Alicia for those who don't know her.
The 35-year-old shot to fame as Cher in the 90s movie, Clueless. She was 18 then. She gave birth to her first child last year. Tabloids slammed her for feeding her child food that she has chewed herself. She is an avid PETA campaigner. And she is still smoking hot!
The Bullet magazine photo shoot features Alicia wearing lingerie posing seductively in front of cameras. She's seen teasingly twirling her hair on one side in one photo.
Another one shows off her nicely toned butt by using the Marilyn Monroe dress-lifting pose.
In the interview, Silverstone told the magazine that she struggled to prove her intelligence after playing the airhead, Cher, in Clueless.
She describes an interview she did in London about the movie.
"I remember doing interviews in London for some movie at the time, and the interviewers would want to talk about the movie, of course, but all I wanted to talk about was murder."
"They probably expected me to be like the Clueless character, but instead I was sitting there saying stuff like, 'And then they anally electrocute!' I pretty much bummed everyone out."
Alicia is working with her Clueless director, Amy Heckerling, on a vampire flick called Vamps. It is set to release in October.


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Learn more about Dyspnea Diagnosis and Treatment at Brigham and Women's Hospital.View More Info »
Dyspnea is shortness of breath, which normally occurs with exercise or exertion. When dyspnea is chronic and not caused by physical exertion, it may be a symptom of an underlying cause. Pulmonary conditions that can cause dyspnea including asthma, chronic bronchitis, chronic obstructive pulmonary disease, emphysema, pneumonia, pulmonary edema, pulmonary hypertension, and other conditions.
Dyspnea also may be caused by a number of heart conditions, including:
- Congestive heart failure (CHF), the inability of the heart to supply sufficient blood flow to the rest of the body. CHF may be caused by a variety of heart conditions.
- Ventricular dysfunction, a condition with one of the heart's ventricles, compromises the heart's ability to pump blood.
- Diastolic dysfunction, a condition of one or both of the heart's ventricles that occurs during the diastolic phase, when the heart fills with blood before pumping it out to the body.
- Cardiomyopathy, which is any disorder that affects the heart muscle and its ability to pump blood effectively.
For patients seeking treatment for dyspnea caused by a cardiovascular condition, Brigham and Women's Hospital (BWH) in Boston provides state-of-the-art treatment in a world-class facility.
Learn more about the dyspnea treatment at BWH.
Treatment for dyspnea at BWHFind A Doctor »
Physicians at BWH treat dyspnea related to many cardiovascular conditions at the Carl J. and Ruth Shapiro Cardiovascular Center, a state-of-the-art facility that provides the most comprehensive cardiovascular care in New England. Equipped with the latest technology, the Center has helped BWH maintain a reputation as one of the top pulmonology and cardiovascular care centers in the United States, providing patients with the latest in artery disease treatment, heart failure treatment and many other services.
The Multidisciplinary Dyspnea/Exercise Intolerance and Performance Evaluation Center is available to evaluate clients with unexplained resting or exertional shortness of breath, and exercise limitations. The Center brings together a core group of clinical and fitness experts from Pulmonary and Cardiovascular Medicine to collaboratively develop streamlined approaches to assessing and treating clients with unexplained shortness of breath. The Center can also provide performance evaluations and make recommendations to bring your physical fitness to the next level. The evaluation begins with a review of any prior assessment and testing that has been performed. Among the tools used by Center staff, in addition to reviewing prior information and a clinical history, includes (1) pulmonary function testing; (2) echocardiography; (3) cardiac catheterization; (4) radiographic and nuclear imaging modalities; and (5) cardiac stress and cardiopulmonary exercise testing. In some cases, simply reviewing the previously collected data will provide an explanation thus preventing unnecessary testing. Based on the findings, recommendations are made.
Comprised of a team of specialists in pulmonary medicine, cardiovascular medicine, neurology, and cardiovascular imaging, the Center strives to greatly reduce work-up time and speed diagnosis for patients with unexplained dyspnea. The team is among few in the nation to offer highly specialized cardiopulmonary exercise testing designed to pinpoint the source of dyspnea and exercise limitation. Advanced Cardiopulmonary Exercise Testing at BWH is performed after placement of a right heart catheter and a radial arterial line to evaluate heart and lung hemodynamics and assess how the patient is utilizing oxygen.
Dyspnea patients at the Center receive expert treatment from some of the country's leading physicians, and the kind of compassionate care that makes all the difference when facing a challenging physical illness.
Physicians in the Shapiro Cardiovascular Center work closely with dyspnea specialists in the BWH Dyspnea Center to accurately diagnose the cause of the dyspnea and create a treatment plan. Treatment for dyspnea depends on the underlying condition, and may include coronary disease treatment, vascular disease treatment and other procedures.
Diagnosing dyspnea
Specialists at BWH diagnose dyspnea using Advanced Cardiopulmonary Exercise Testing. In this procedure, catheters placed in the body monitor the patient during exercise to determine how the body is using oxygen and to evaluate the function of the heart and lungs. BWH is one of only a few hospitals in the U.S. that offers Advanced Cardiopulmonary Exercise Testing. Many other standard forms of diagnostic testing – including noninvasive cardiopulmonary testing, electrocardiogram, computed tomography and pulmonary function testing – tend to provide inconclusive results and/or have a higher rate of misdiagnosis.
Learn more now about BWH and dyspnea, as well as heart valve replacement surgery, atrial fibrillation treatment, and the many other services available at the Cardiovascular Center.Learn more about Dyspnea Diagnosis and Treatment at Brigham and Women's Hospital. »
This page was last modified on 8/15/2016


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If ever someone wanted to study how so-called humanitarian interventions can mess up entire regions, they should start with the unilateral declaration of independence of Azawad and the so-called Touareg Rebellion in Mali.
Of all the things that can be said about this armed conflict opposing touareg groups, radical islamic groups and the Malian armed forces, the most striking is the recurrent fumbling around of external powers in the region (a very nice discussion can be found here and some keys for understanding what is going on here). Interference is certainly the politically more appropriate word, however, interference suggest a strategic and persistent approach to influencing another state's politics and society. And this is exactly not the case in this African region. The United States, the UK, France and others, notably the African neighbours like Niger and Algeria in this case, do a little here and there, financing this group, arming another, giving this advise to a government and training that military, all in a pretty incoherent way and with rather parochial and short-sighted interests in mind, and then, when all blows up, they throw their hands up in the air and cry out "It was not me!".
The "not-me" is nicely supported by most of academic conflict analysis, which endogenizes conflict causes and dynamics. Whether conflicts are fought for material resources or ethnic identity or because of seemingly failing states, typically the Colliers, Bates, Humphreys and Fearons of the academic world identify the causes of those conflicts arising from greed, incompetence, corruption, lack of public goods and all other kinds of nasty things inside the states concerned.
Colonial legacies, trade and development aid, globalisation and international organisations, and most particularly all this "fumbling around" simply do not appear at all or very selectively. The UCDP conflict encyclopedia (already discussed in a former post) for instance mentions only Libya – our consenusal baddy – as outsider in the Azawi conflict and no one else.
Yet, if there is one thing observers on the ground and journalists of the region seem to be agreeing upon in the troubles that Northern Mali are going through it is the major role played by the intervention in Libya, the proliferation of small arms, the various interests and inminglings of Algerian, Mauritania, Niger, Nigeria and Western powers, and the US-led, Algerian supported "war on terror" in its various forms in the region. Smuggling and trafficking certainly do play a big role in the livelihoods of the people in these regions as well as kidnappings are important for the finances of armed groups.
Just who exactly has contributed, instigated, and benefitted from these activities and what alternatives have been destroyed and discarded, remains entirely unclear. As Jeremy Keenan points out it seems unlikely that the Touareg would destroy their own economic base, tourism, through kidnappings – unlikely, of course, if one does not assume that Africans in general and Touareg in particular are manipulated by short-term interested, greedy warlords.
However, as Patricia Allemonière points out this money has also allowed financing public services, health care and schooling in a region that has been entirely abandoned by the Malian state due to its fiscal incapacity to provide public services across a difficult territory. The reasons why the Malian state has abandoned this region are manifold and deeply linked to global policies whether constraints of various aid policies, including the incredible efficiency of NGOs to substitute the state, geostrategic pushing and hoving in the region (as Jeremy Keenan contends), the regional embroglio or the continued paternalism of the former colonial power, France.
Obviously, the question is not whether external forces or internal dynamics are more responsible for creating conflict situation as in Norther Mali as if such a tradoff would indeed make sense….rather the two troublings questions are, as far as the politics of academia are concerned, why so many Western scholars obstitinately ignore external influences (and vicious thoughts could be formulated that this is not unrelated to the denial of colonial wrongdoings) , and how the interaction of such a large array of factors over different times spanes can be sensibly analysed. Both actually bump into the same major problem, namely that social science research is not value-free as so passionately claimed, but runs up against a wall of normative ideas. The very cherished idea that humanitarian interventions are, in principle and really, good, that they stop the killing and that they "free" populations is one of them and yet, looking at the Malian case it is evident that they are just one more episode of a long history of fumbling around…


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5 Of The Best Brown Girl Friendly BB Creams
BB creams have been taking the U.S. by storm for the last few years.
These Blemish Balm or Beauty Balm wonders are wildly popular in Asia for their skin care and makeup combining qualities. Many Asian BB creams put together the power of moisturizer, primer, SPF, anti-aging, brightening, and tinted moisturizer all in one simple and easy to use product. Unfortunately, most of them come in one maybe, two shades. The ones that have made their way to the U.S. come in a couple more shades, but if you're a certain shade of brown, you'll find that BB creams tend to exclude you.
However, in recent months, a number of brands have put out BB creams that don't call Halle Berry's complexion "dark," and we've put together a list of some of the best to try should your heart so desire.
Check out what they are!
1. Iman Cosmetics BB Créme
This awesome new kid on the block comes in 6 shades ranging from fair to very deep. What I love most about it is although BB creams tend to err on the moisturizing side, it didn't make my oily skin feel like an oil slick and it had decent coverage.
2. Sleek MakeUP Be Beautiful Blemish Balm
This British high street makeup brand has always committed to making quality makeup at really great prices for ALL skin tones. So it's no surprise that their BB cream comes in a great range of seven shades. I also loved that it provides more coverage than your average BB.
3. Illamasqua Skin Base Foundation
It may be safe to say the Brits get it right when it comes to having an extensive range of shades in BB creams. Illamasqua's version has 17 shades! The formula is best suited for those with drier skin.
4. Smashbox Camera Ready BB Cream SPF 35
So the Dark in this 5-shade range is more like a caramel brown, but since many BB creams don't even come close to that shade, it makes the cut.
5. Maybelline Dream Fresh BB Cream
This is a BB cream for those who require very little—and I mean VERY little coverage. I have pretty decent skin and found that it was too light even for me, but the Dark was deep enough to match my NW47 skin.
Have you tried BB Creams yet?
-Danielle Gray


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|You are in: World: Africa
Sunday, 31 December, 2000, 11:28 GMT
Mozambique braces for floods
By Greg Barrow in Mozambique
The Mozambican Government is bracing itself for the possibility of more flooding as the rainy season in southern Africa gets underway.
Much has been done during the dry season to reconstruct the roads, bridges and buildings that were destroyed.
But there are fears that all of this could be swept away again if the rivers of the region burst their banks in the New Year.
Crops destroyed
Rain is both the bringer of life and death in Mozambique.
It provides water for the rice and maize which is grown in the southern part of the country. But when rivers burst their banks, the fields become flooded with red muddy water, and the crops are destroyed.
People are forced to flee their homes, and many fall victim to water borne diseases.
Now, the Mozambican Prime Minister, Pascoal Mocumbi, admits his government is awaiting the new rainy season with trepidation.
Already, several thousand people have been cut off by floods caused by the first rains.
The ground in Mozambique is so waterlogged that it only takes a cloudburst or a shower to drench the sodden earth.
Whole communities in the south of the country are still dependent on United Nations aid agencies for food and support.
Situation serious
The World Food Programme has described the current situation as serious.
It is most concerned about communities that have moved back to areas which were exposed to the worst of the flooding earlier this year.
With further flooding a very real possibility, the good sign is that the UN will be better prepared for it this time around.
See also:
03 May 00 | Africa
Mozambique picks up the pieces
28 Apr 00 | Africa
Flood baby's family start afresh
18 Apr 00 | Africa
Mozambique: Sowing seeds of hope
22 Nov 00 | Africa
Heavy rains revisit Mozambique
Internet links:
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Links to more Africa stories are at the foot of the page.
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About This Activity
GLeau Run is a fundrainig event benefiting the American Cancer Society's Relay For Life event. This night time run through beautiful downtown Lake Charles will be fun for the entire family with food, fun, and rememberance. We will also have luminaria bag and sky laterns available for purchase at the event in rememberance of loved ones who are battling or have loss the battle with cancer.
Event schedule and times
Late Registration/Check-In: 6:30 PM
Opening Ceremonies: 7:30 PM
Race Begins at: 8:15 PM
Organizer Info