Copper vaporization

Atomic- Vapor Laser Isotope-Separation. Although the technology has been around since the 1970s, laser isotope separation has only recently matured to the point of industrialization. In particular, laser isotope separation for the production of fuel and moderators for nuclear power generation is on the threshold of pilot-plant demonstrations in several countries. In the atomic vapor laser isotope-separation (AVLIS) process, vibrationaHy cooled U metal atoms are selectively ionized by means of a high power (1—2 kW) tunable copper vapor or dye laser operated at high (kHz) repetition rates (51,59,60). 

Dye lasers, which can lase in either pulsed or CW formats. They may be pumped by flashlamps or by other lasers such as copper vapor, argon ion or by frequency doubled Nd YAG lasers. 

LLNL AVLIS Laser. The first WFS measurements using a Na LGS were performed at LLNL (Max et al., 1994 Avicola et al., 1994). These experiments utilized an 1100 W dye laser, developed for atomic vapor laser isotope separation (AVLIS). The wavefront was better than 0.03 wave rms. The dye laser was pumped by 1500 W copper vapor lasers. They are not well suited as a pump for LGSs because of their 26 kHz pulse rate and 32 ns pulse length. The peak intensity at the Na layer, with an atmospheric transmission of 0.6 and a spot diameter of 2.0 m, is 25 W/cm, 4x the saturation. The laser linewidth and shape were tailored to match the D2 line. The power was varied from 7 to 1100 W on Na layer to study saturation. The spot size was measured to be 7 arcsec FWHM at 1100 W. It reduced to 4.6 arcsec after accounting for satura-... 

Reaction of the l-thia-2,5-diborole 63 with potassium leads to liquid 64a [85], and dehalogenation of (Z)-2,3-bis(dichloroboryl)hexene with copper vapor or Na/K alloy results in the formation of crystalline 64b [86], both in low yields (Scheme 3.2-34). 

The condition for observing induced emission is that the population of the first singlet state Si is larger than that of So, which is far from the case at room temperature because of the Boltzmann distribution (see above). An inversion of population (i.e. NSi > Nso) is thus required. For a four-level system inversion can be achieved using optical pumping by an intense light source (flash lamps or lasers) dye lasers work in this way. Alternatively, electrical discharge in a gas (gas lasers, copper vapor lasers) can be used. 

Figure 11.44 is a schematic diagram of one LIF instrument (Stevens et al., 1994 Brune et al., 1998). An air-cooled copper-vapor laser pumps a dye laser whose output at 616 nm is doubled to generate the 308-nm exciting radiation. An OH reference cell in which OH is generated from the thermal dissociation of water... 

The use of laser-induced fluorescence (LIF) for tropospheric HO and H02 measurements was reported by Hard and co-workers (108-110), who developed a fluorescence technique based on pumping the air sample into a low-pressure cell (FAGE) and exciting it with a copper vapor laser-pumped dye laser with a high repetition rate. Their H02 measurements were not made in conjunction with enough other supporting measurements to allow an accurate test of photochemical models from the results. 

Detection of Carbon-Fluorine Bonds in Organofluorine Compounds by Raman Spectroscopy Using a Copper-Vapor Laser ... 

Figure 9. Design of the dye laser amplifier. Ultrafast laser pulses are amplified roughly 10,000 times by seven passes through a dye jet pumped by a copper vapor laser.

Monoatomic copper vapor was generated by directly heating a tungsten-rod assembly around which copper wire was wrapped. The rate of metal atom deposition (10-12 K) was continuously monitored with use of an in situ quartz-crystal microbalance assembly. Cu(C2H2) and Cu(C2H2)2 were detected by spectroscopic methods. 

Copper vapor laser A pulsed source of coherent radiation emitting at 578.2 and 510.5 nm from excited copper atoms. 

See argon ion-, CO2-, excimer, copper vapor-, helium-neon-, krypton-, nitrogenlasers. 

See argon ion, helium-cadmium, chemical, CO2 copper vapor, diode, dye, excimer, free electron, free-running, gas, helium-neon, krypton ion, mode-locked, neodymium, nitrogen, Q-switched, solid state, and ruby laser. 

Fig. 11. Schematic view of the copper vapor laser pumped dye laser system developed at Harvard for the detection of OH and HO2 radicals in situ from balloon-borne descent probes.

Sindrup SH, Brosen K, Bjerring P, Arendt-Nielsen L, Larsen U, Angelo HR, Gram LF. Codeine increases pain thresholds to copper vapor laser stimuli in extensive but not poor metabolizers of sparteine. Clin. Pharmacol. Ther. 1991 49 686-693. 

After aqueous impregnation, copper(II) chloride is present as a highly dispersed phase on the surface of zeolites. After a thermal treatment in nitrogen and subsequently in ammonia, the copper appears to be present as isolated ions in the zeolite. Therefore, impregnation is a suitable method to prepare non-acidic copper-zeolites. As copper vaporization is limited with a catalyst not having a cation excess, a zeolite pre-exchanged with ammonium ions and consecutively impregnated with copper seems especially suitable. 

Douglass, S. E., Massey, S. T., Woolard, S. G., Zoellner, R. W. Reductive versus coupling pathways in the reactions of nickel and copper vapors with the monohalobenzenes. Transition Metal Chemistry (Dordrecht, Netherlands) 1990, 15, 317-324. 

Visible light 511-578 Copper vapor Pulse-train... 

Haba et al. [28] have computed the temperature distributions induced by pulsed irradiation of Mn-Zn ferrite with a copper vapor laser (k = 511 and 578 nm) under the processing conditions of Table 18.1. This particular source is characterized by a top hat, circular intensity distribution. 

Aucfiio RQ, Rubin NV, Smith bw and wine-EOEDNEE JD (1998) Ultratracc determination of Pt in environmental and biologcal samples by electrothermal atomization laser-excited atomic fluorescence using a copper vapor laser pumped dye. J Anal Atom Spectrom 13 49-54. 

Fig. 20. Cryostat with electrical control h) bath liquid d) copper vaporizer f) down pipe h) siphon h) condenser 1) liquid nitrogen r) relay Sj) power supply of about 2 volts Sa) power supply of about 18 volts t) vapor pressure thermometer u) pressure head regulator (manostat) v) electromagnetic gas valve the valve plunger must be sufficiently heavy not to stick in its seat.

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