Infiltration Laser

These structures were recorded by a vectorial focal spot scanning in a spiral-by-spiral method rather in a raster layer-by-layer mode using a PZT stage. Such spiral structures fabricated in SU-8 have optical spot bands in near-lR [24], telecommunication [25], and 2-5 pm-IR region [26] or can be used as templates for Si infiltration [11]. It is obvious, that direct laser scanning is well suited for defect introduction into 3D PhC, as demonstrated in resin where a missing rod of a logpUe structure resulted in the appearance of a cavity mode in an optical transmission spectriun [27]. 

Acknowledgements We are indebted to our colleagues, coauthors, and students for numerous discussions on various aspects of laser microfabrication. We acknowledge the discussions and insights of Profs. S. John and G. Ozin on the properties of spiral PhC and for Si-infiltration of SU-8 spiral structures. We also acknowledge the comments of Prof. V. Datsyuk on field enhancement effects. 

The Final Analysis. The SEM analysis of the liquid extrusion shows that sulfur is present in quantities much greater than the monosulfide of calcium could provide. The most probable explanation is that part of the sulfur is present in polysulfide anions, as the infiltration conditions appear to favor their formation (18). A sample of the yellow solution obtained by leaching fragments under nitrogen was therefore analyzed by laser Raman spectrometry to determine if the absorption... 

Figure 15 Three microscopic hematoxylin and eosin (H E) stained cross-sections of a rabbit artery two weeks post PDT treatment with lutetium(III) texaphyrin PCI-0123 (lOpmol/kg per day for three days and illumination with 200J/cm, 250mW/cm and 732 nm laser light 5 h post injection). Here, (A) and (C) are above and below the treatment site and (B) is at the treatment site. The aorta, above the treatment zone, is shown. The intima (i) is extensively thickened and heavily ladened with foam cells. The atheroma completely lines the wall, thereby significantly narrowing the lumen (1). The outer wall, adventitia (a), and media (m) are normal and show no evidence of infiltrating disease. The photoirradiated site (B) is now normal (i.e., devoid of lesions), while the media muscular wall is intact with no necrotic regions being visible. The field below the treatment site (C) is heavily burdened with plaque (x40). Reproduced from [243] by permission of Mary Aim Liebert, Inc. Publishers...

Nowadays, many advanced techniques are available in the ceramic industry to coat a solid layer onto a solid surface or to make ceramic materials with special properties [99-1 IS], such as spin-coating [99], chemical vapor deposition [100-106], and chemical vapor infiltration [106-109], thermal spray [110-112], plastic spray [113], and spray-coating [114]. The deposition can be caused by conventional heating, by laser beam, or by microwave heating. 

Secondly, VOCs react with indoor ozone to produce sub-micron-sized particles [ 101,102 ]. Thus, terpenes, which are commonly found in many household consumer products, interact with ozone, which is also widespread in indoor air through outdoor infiltration and the use of office equipment like laser printers and photocopiers, to form particles. Such reactions can markedly increase the number concentrations and mass concentrations of sub-micronsized particles. In addition, styrene and 4-phenylcyclohexene react with ozone to generate appreciable amounts of aldehydes [4,101]. 

A number of other strategies have been investigated in order to improve the quality (selectivity and fluxes) or the synthesis efficiency of zeolite membranes by pre-treatment of the support. Most of these treatments are listed in [49], and include laser ablation, utilisation of diffusion barriers to limit sol infiltration, oxidation of stainless-steel supports, deposition of iron oxide to favour heterogeneous nucleation on the support and the use of acid attacks to activate the surface. 

Postspraying treatment such as annealing of coatings to reduce microporosity by solid-state diffusion, hot isostatic pressing of coatings, laser surface densifi-cation and infiltration of coatings with polymers or by the sol-gel process. 

FIGURE 22.42 Random laser emission spectrum of a DOO-PPV in toluene solution that is infiltrated into an opal photonic crystal. The inset shows the opal, which is composed of silica spheres in an FCC lattice and the laser excitation and collection geometries. (From Poison, R.C., Chipouline, A., and Vardeny, Z.V., Adv. Mater., 13, 760, 2001. With permission.)... 

Laser assisted chemical vapor deposition (LCVD) yields continuous or discontinuous low diameter fibers directly from the vapor phase by tip growth. Chemical vapor deposition (CVD) on the surface of a small diameter, preferably sacrificial, precursor fiber yields a large diameter fiber or microtube. Chemical vapor infiltration (CVI) can change the chemistry of precursor fibers by infiltration of a chemically reactive vapor species. Finally, laser vaporization (LV) of carbon-metal mixtures yields highly entangled mats of nearly endless nanotube ropes. 

In addition to displays, liquid crystals have also been used extensively in tunable photonic devices, such as optical phased array for laser beam steering, variable optical attenuator (VOA) for telecommunications, tunable-focus lens for camera zoom lens, LC-infiltrated photonic crystal fibers [1,2], diode laser-pumped dye-doped LC laser, just to mention a few. 

The HCC nodules were localized on computed tomographic (CT) scans and the injection site was infiltrated with 20 ml of 1% lidocaine. Under CT guidance, up to four sheaths were inserted using the Seldinger technique. A special heat-resistant protective fiber was then introduced. For the positioning of the applicators we routinely used the CT guidance in all patients this is because of later procedures and because it allows immediate reaction in cases of bleeding or pneumothorax. After the patient was positioned on the MRI table, the laser fiber was inserted into the protective catheter. MR sequences... 

Figure 13-21. (a) Schematic illustration of a dye-infiltrated opalphotonic crystal usedfor measuring lasing action in the [111] direction, (b) the [111] laser emission spectrum (solid curve) and optical density spectrum for an Oxazine 725 dye-infiltrated opal, and (c) the laser emission spectrum (solid curve) and optical density spectrum (dotted curve) for a [2 2 0] Stilbene 420 dye-infiltrated opal (Shkunov, 2002). 

Similar mirrorless laser-like emission was observed for silica inverse opals infiltrated with rhodamine 6G [105]. Figure 30.15 shows the latex opal obtained... 

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