Ultrahigh-pressure Mercury Lamp Research Articles

Irradiation effects and photostability of aerosil-filled polyurethane as a matrix for laser solid-state elements

Photooxidation processes during irradiation of the aerosil-filled polyurethane films, based on oligooxypropylene glycol, toluene diisocyanate and trimethylolpropane, for a use as the active media of solid-state lasers were investigated by means of the IR-spectroscopy and dynamic mechanical analysis (DMA) methods, depending on the inorganic dopant concentration (5 and 7 wt%). The IR-spectroscopic experiments showed that the introduction of aerosil slowed down these processes. Data from dynamic mechanical studies indicated that irradiation of aerosil-filled polyurethane matrices caused an increase in its structural heterogeneity and a drop of the elastic modulus. During irradiation of the polyurethane material with 7 wt% of aerosil, a partial destruction of the nanofiller spatial network was possible due to dispersion of the irradiation energy by the nanoparticles. The obtained results demonstrated a positive effect of the aerosil nanofiller on the polyurethane material stability under irradiation with an ultra-high pressure mercury lamp.

ChemInform Abstract: A Novel Thiochromone‐Type Photolabile Protecting Group for Carbonyl Compounds.

A novel photolabile protecting group, thiochromone S,S-dioxide, possessing the 1,2-diol group for protection of ketones and aldehydes is described. Photodeprotection of the successfully protected carbonyl derivatives proceeded smoothly under photoirradiation filtered through Pyrex glass (>280 nm) using an ultrahigh-pressure mercury lamp to recover the corresponding carbonyl compounds and the starting protecting group.

Research on the Dimming Characteristics of Short Arc Ultra-High Pressure Mercury Lamps for Projection Applications

The voltage, current and power are measured for short arc ultra-high pressure mercury lamps (UHP) with rating power 250 W driven by 50 Hz square waveform power supply. It is found that the curve slope of voltage-current characteristics is positive in most of the power range, and negative around 170 W. The photometric, colorimetric and electric parameters are measured with an integrating sphere system couple with a spectrometer in UHP dimming experiments. The results show luminous flux increases with power linearly. The luminous efficacy and color rendering index (CRI) reduce with power reduction because of the decrease of spectral continuum. The mercury pressure are calculated with the full width at the half maximum (FWHM) of 546 nm spectral band, which is 6.2-11.0 nm according to the mercury pressure 15.3-25.8 MPa for UHP power 43-258 W.

70.5L: Late‐News Paper: Low Temperature Curable Cu Ink and Fine Inkjet‐printed Patterning

AbstractCu wiring patterns of fine pitch less than 20 μm have been successfully achieved by inkjet printing technology with the assistance of surface energy controlled patterns formed by the exposure of ordinary ultrahigh pressure mercury lamp. The curing condition of Cu ink is as mild as 150°C in non‐reducing atmosphere.

A novel thiochromone-type photolabile protecting group for carbonyl compounds

A novel photolabile protecting group, thiochromone S,S-dioxide, possessing the 1,2-diol group for protection of ketones and aldehydes is described. Photodeprotection of the successfully protected carbonyl derivatives proceeded smoothly under photoirradiation filtered through Pyrex glass (>280 nm) using an ultrahigh-pressure mercury lamp to recover the corresponding carbonyl compounds and the starting protecting group.

ChemInform Abstract: Syntheses of Phospholipids Containing 2-Nitrobenzyl Ester Moieties at the Terminals of Alkyl Chains and Properties of Photodegradable Liposomes from the Lipids.

Phospholipid 1a bearing 2-nitrobenzyl ester moieties as a photocleavable group at the terminal of alkyl chains was synthesized from the corresponding terminal carboxy-bearing phospholipid 2 by the reaction with 2-nitrophenyl-substituted diazomethane. Phospholipid, 1b bearing α-methyl-2-nitrobenzyl group, 1c bearing 4,5-dimethoxy-2-nitrobenzyl group, and 1d bearing α-methyl-4,5-dimethoxy-2-nitrobenzyl group were similarly synthesized by the use of the respective diazo compounds. The order of photolysis rates of 2-nitrobenzyl ester linkage of phospholipids by ultrahigh-pressure mercury lamp is 1b ≥ 1d > 1a > 1c. Liposomes of 1a—1d containing calcein in the inner aqueous layer were prepared by vortexing, sonication, and gel-filtration. UV irradiation resulted in fast release of the entrapped fluorescence dye. The order of release rates : 1b ≥ 1d > 1c > 1a is consistent with that of photolysis rates except for 1c, which has poor retention of the dye.

Measuring the pressure in ultrahigh-pressure mercury arcs

Ultrahigh-pressure (UHP) mercury lamps are important as high-brightness light sources for digital projection. Hg pressures are usually above 20 MPa and difficult to measure. We have built special UHP lamps with a liquid Hg condensate in a temperature-controlled reservoir, allowing us to tune the Hg vapor pressure p between 14 and 30 MPa. As a simple measure for p, we recorded the width Δλ of the 546 nm Hg line while varying p and also the lamp current I and voltage U. The data define a function p(Δλ,I,U) that will deliver p to better than 3% from simple measurements of Δλ, I, and U for most UHP lamps in the important 100–200 W power range. The method is applied to sample lamps, yielding pressures up to 26 MPa and demonstrating how filled Hg amount, burning position, arc gap, and lamp power affect the pressure. The effective temperature of typical UHP lamps is found to be 2400 K. We also derive an improved characteristic U(d,p,I) for the dependence of the arc voltage on arc gap, pressure, and current for e...

Photo-assisted crystallization of zirconia thin films prepared using chelate compounds

A highly crystallized and smooth-surfaced zirconia (ZrO2) thin film was prepared using a precursor solution with 2,4-pentanedione addition (molar ratio of 1:1 for zirconium alkoxide); the film was irradiated with ultraviolet (UV) light using an ultrahigh-pressure mercury lamp. This thin film was compared with another thin film, which prepared using a precursor solution without additives and UV irradiation. The crystallinity of ZrO2 thin films improved with increasing 2,4-pentanedione addition and UV irradiation time and changed according to the type of organic additives. These results occurred presumably because the orientation of polymerization in zirconium alkoxide units and stability of chelate compounds for UV irradiation were controlled under these conditions. In addition, the method was effective for lower-temperature crystallization of highly crystallized, smooth-surfaced thin films.

Light Sources and Ballast Circuits

According to the machinery statistics by Ministry of Economy, Trade and Industry (METI), the total of domestic light bulb production in 2006 was 1,101 million (88.5% year-on-year). Production for general purpose illumination light bulbs and halogen light bulbs accounted for 122 million (99.2% y/y) and 45 million (96.3% y/y), respectively. The total of fluorescent lamp production was 988 million (114.9%) and the production of general purpose fluorescent lamps excluding backlights accounted for 367 million (101.7% y/y). Further, HID lamp production was 10 million (106.3% y/y). What is noteworthy regarding such lamp production is that, similar to the previous year, the sales volume (amount) of lamps for general illumination exceeded 100% against the previous year, indicating a steady shift to high value added products. Major lighting exhibitions in 2006 included the Light + Building Trade Fair held in Frankfurt in April and the Light Fair International 2006 held in Las Vegas, U.S.A. in May, both of which demonstrated signs of acceleration toward energy saving, high efficiency and resource saving. As for incandescent lamps, products filled with larger atomic weight gases aiming at higher efficiency/longer life are becoming the mainstream. As for new technologies, it was experimentally demonstrated that infrared radiation can be suppressed by processing micro cavities to metal plates made of tungsten, tantalum, etc. For fluorescent lamps, straight and circular fluorescent lamps achieving a longer life/higher luminous flux maintenance factor continued to be widely developed/launched again this year. For compact fluorescent lamps, energy saving/high efficiency products, multifunctional type products combined with LED and new shaped products were launched. As to HID lamps, ceramic metal halide lamps with high efficiency, improved color rendering, longer life and higher luminous flux maintenance factor were commercialized one after another. Numerous studies and analyses, on discharge models were reported. Further, studies on ultra high-pressure mercury lamps as light sources for projectors are becoming the mainstream of HID lamp related researches. For high-pressure sodium lamps, many studies on plant growing and pest control utilizing low insect attracting aspects were also reported in 2006. Additionally, for discharge lamps, the minimum sustaining electric power for arc tubes employed in electrode-less compact fluorescent lamps was investigated. For Hg-free rare-gas fluorescent lamps, a luminance of 10,000cd/m2 was attained by a 1 meter-long external duplex spiral electrode prototype using Xe/Ne barrier discharge. As to startup circuits, the commercialization of energy saving and high value added products mainly associated with fluorescent lamps and HID lamps are becoming common. Further, the miniaturization of startup circuits for self electronic-ballasted lamps has advanced. Speaking of the overall light sources and startup circuits in 2006 and with the enforcement of RoHS in Europe in July, the momentum toward hazardous substance-free and energy saving initiatives has been enhanced from the perspective of protecting the global environment. It is anticipated that similar restrictions will be globally enforced in the future.

Synthesis and characterization of photosensitive methacrylates to give heat-resistant polymers

New photosensitive monomers having multiple methacryloyloxy groups were synthesized by the reaction of naphthalene and biphenyl derivatives containing two or more glycidyloxy groups with methacrylic acid. The obtained photosensitive monomers were mixed with polymerization initiators (1 wt% AIBN and/or BIPE) and a reactive diluent (20 wt% DPCA60). The mixtures were termed as compounds. The compounds were converted into the insoluble gel products by heating or photo-irradiation with an ultra high-pressure mercury lamp. We also measured the heat resistance of the insoluble gel products by thermogravimetry and investigated the correlation between the heat resistance and the chemical structures of photosensitive methacrylate composites. All of the insoluble gel products showed the heat-resistance over 260 8C and particularly the compound having the largest number of methacryloyloxy groups had the highest heat-resistance among them. This compound exhibited the highest consumption rate of the photosensitive group and it was in accordance with the result of the reactive photo-polymerizability measured by the gray scale method.

Wavelength Dependence of Crystallization of Alkoxy-Derived ZrO2 Thin Films Prepared by Ultraviolet Irradiation

Wavelength dependence was observed in the ultraviolet (UV) irradiation-assisted crystallization of alkoxy-derived ZrO2 thin films. The surface grains of thin films deposited on Si(100) substrates became enlarged by UV irradiation using an ultrahigh-pressure mercury lamp. The crystallinity of thin films deposited on Si(100) substrates was improved by UV irradiation using a low-pressure mercury lamp. The reaction using the ultrahigh-pressure mercury lamp depended on the substrate type.

Infrared continuum radiation from high and ultra-high pressure mercury lamps

Infrared (IR) continuum radiation from the arc of high and ultra-high pressure (UHP) mercury lamps was measured and modelled. Three major contributions to the IR continuum are electron–atom bremsstrahlung, which is dominant, electron–ion bremsstrahlung and electron–ion recombination radiation. The line width of the resonance broadened Hg 71S0 to 61P1 transition at 1014 nm was used to determine the arc core Hg density, and the radiance of this line was used to determine the arc temperature as a function of radius. The temperature map for the UHP lamp was checked using the Bartels method on the 546 nm line of Hg. Model results based on recently published electron–atom bremsstrahlung coefficients were found to be in good agreement with measurements across the near IR.

52.1: A New Driving Scheme for AC-Type Ultra-High-Pressure Mercury Lamp with Highly Stabilized Light Output

A new driving scheme for AC type ultra high pressure mercury lamp has been developed. The new driving scheme provides a highly stabilized arc over thousands of hours without any fluctuations of light output due to the current modulation. The design freedom of the color sequential projection optics expands dramatically.

Control of crystallization and crystal orientation of alkoxy-derived SrBi2Ta2O9 thin films by ultraviolet irradiation

A 650 °C annealed thin film was found to be a single phase of SrBi2Ta2O9 (SBT) and showed the c-axis orientation without ultraviolet irradiation. The crystallinity and crystal orientation of the thin films were improved by ultraviolet irradiation using an ultrahigh-pressure mercury lamp (UHPML) or a low-pressure mercury lamp (LPML) under three conditions. In particular, the crystal orientation of the 650 °C annealed thin films dramatically changed by ultraviolet irradiation using a LPML at room temperature or using an UHPML at 150 °C. The 650 °C annealed SBT thin film prepared by ultraviolet irradiation using an UHPML at 150 °C showed a remanent polarization (Pr) of 4.3 μC/cm2 and a coercive electric field (Ec) of 101 kV/cm at 10 V.

Preparation of (Bi, Sb) 2S 3 semiconductor films by photochemical deposition method

The photochemical deposition (PCD) technique has the advantages of economy, the capability of large area deposition and of a fast reaction rate. In this report, the PCD method using UV light of an ultra-high pressure mercury lamp was applied to form (Bi x , Sb 1− x ) 2S 3 semiconducting compounds from solutions containing BiCl 3 and/or SbCl 3 Na 2S 2O 3 at pH in the acidic range 1–3. The pH of the solution was adjusted with the addition of dilute HCl solution. The substrate for the film deposition was pretreated onto the commercial pyrex-glass plate surface with the well-known solution agent of Pd activator plus Sn sensitizer. In the PCD process, the film is only deposited onto the irradiated region of the substrate so as to make a pattern using the mask. This deposition process shows the heterogeneous nucleation and growth mechanism on the substrate surface. The deposition rate of the film using a 500 W mercury lamp was about 1 μm/30 min. The crystallization characteristics of the amorphous (Bi 2S 3) deposits were studied by means of X-ray diffraction, thermal analysis (DSC) and optical transmitted spectra evaluation in order to clarify the amorphous to crystal phase transformation. The amorphous deposits showed gradual light absorption in a wide range of optical wavelengths. On the contrary, annealed film showed a sharp absorption edge near 800 nm. The crystallization temperature of the amorphous deposits was about 250–300°C.

ZnBeSe epitaxy layers grown by photo-assisted metalorganic chemical vapor deposition

Low-temperature growth of ZnBeSe epilayer on GaAs substrates has been carried out at low-pressure (LP) by photo-assisted metalorganic chemical vapor deposition (MOCVD) using a ultrahigh-pressure mercury lamp as a light source. High-temperature growth of ZnBeSe has been also achieved by LP-MOCVD without light irradiation. It was found that the full-width at half-maximum of the diffraction peak of ZnBeSe epilayer increased with increasing irradiation intensity and growth temperature. The intensity of the emission band related to the excitons was obviously reduced due to poor quality of epilayer at high irradiation intensity and the deep-level emission band was predominant in the spectra.

Syntheses of Phospholipids Containing 2-Nitrobenzyl Ester Moieties at the Terminals of Alkyl Chains and Properties of Photodegradable Liposomes from the Lipids

Abstract Phospholipid 1a bearing 2-nitrobenzyl ester moieties as a photocleavable group at the terminal of alkyl chains was synthesized from the corresponding terminal carboxy-bearing phospholipid 2 by the reaction with 2-nitrophenyl-substituted diazomethane. Phospholipid, 1b bearing α-methyl-2-nitrobenzyl group, 1c bearing 4,5-dimethoxy-2-nitrobenzyl group, and 1d bearing α-methyl-4,5-dimethoxy-2-nitrobenzyl group were similarly synthesized by the use of the respective diazo compounds. The order of photolysis rates of 2-nitrobenzyl ester linkage of phospholipids by ultrahigh-pressure mercury lamp is 1b ≥ 1d > 1a > 1c. Liposomes of 1a—1d containing calcein in the inner aqueous layer were prepared by vortexing, sonication, and gel-filtration. UV irradiation resulted in fast release of the entrapped fluorescence dye. The order of release rates : 1b ≥ 1d > 1c > 1a is consistent with that of photolysis rates except for 1c, which has poor retention of the dye.

Photochemical separation and co-precipitation of lanthanides in nitric acid solution

Mutual separation of lanthanide elements was carried out using photochemical techniques. Light from an ultrahigh pressure mercury lamp was used to irradiate a nitric acid solution containing fourfold mixtures of lanthanide elements (Nd, Sm, Eu and Gd), (NH 4) 2SO 4 and isopropyl formate. Nd, Sm and Eu formed precipitates as a function of the irradiation time, but Gd did not co-precipitate. It was concluded that ligand photosubstitutional reactions can be initiated by f-state excitation provided that the reduction potential of the target element is sufficiently low. When La was introduced instead of Gd, La co-precipitated together with Nd, Sm and Eu. To explain these results, Nd–Gd and Nd–La systems were photolysed for comparison, and the difference in precipitation behaviour between these two systems was explained by the different sizes of the ions of these elements. © 1997 Elsevier Science S.A.

Separation and Coprecipitation of Lanthanides and Americium by Photolysis

Photochemical techniques are used for the mutual separation of lanthanide elements. By emitting light from an ultrahigh-pressure mercury lamp to a nitric acid solution that contains fourfold mixtures of lanthanide elements (neodymium, samarium, europium, and gadolinium), (NH4)2SO4, and isopropyl formate, neodymium, samarium, and europium are photoreduced and form Ln2+ sulfates, while gadolinium is not photoreduced and does not coprecipitate. When lanthanum is introduced instead of gadolinium, lanthanum coprecipitates along with neodymium, samarium, and europium. These results are explained by photolyzing Nd-Gd and Nd-La systems for comparison, and the difference in precipitation behaviors between these two systems is explained by the differences in ion size of these elements. Photolysis is also performed for a Nd-Am system. Am3+ is carried along with neodymium and coprecipitated. As a way to decrease the amount of americium carried along with neodymium, americium is photo-chemically oxidized by emitting light from a deuterium lamp as well as from a mercury lamp. The fraction of americium carried with neodymium decreases with the use of this technique. This result is also explained by the differences in ion size of these elements.

AN ELECTRON SPIN RESONANCE STUDY OF OXYGEN RADICALS ON HYDROXYAPATITE

Oxygen was activated on hydroxyapatite which was previously heated in vacuo above 773K or irradiated with an ultra-high pressure mercury lamp. In the former method O2- species gradually formed and slowly decayed. In the latter method two types of O3- species were formed and one species rapidly decayed. The different behavior should depend not only on chemical species but on their location.