Titanium, masking

Ion beam milling is carried out to cut through the HgCdTe wafer 30 and the epoxy layer 34, so as to electrically isolate the individual HgCdTe detector elements 42 by channels 44. Each element is in electrical contact with an individual contact point 22 and its electrical lead 36 Next, the titanium mask is removed by etching and the surface is cleaned. 

It is therefore possible to determine cations such as Ca2+, Mg2+, Pb2+, and Mn2+ in the presence of the above-mentioned metals by masking with an excess of potassium or sodium cyanide. A small amount of iron may be masked by cyanide if it is first reduced to the iron(II) state by the addition of ascorbic acid. Titanium(IV), iron(III), and aluminium can be masked with triethanolamine mercury with iodide ions and aluminium, iron(III), titanium(lV), and tin(II) with ammonium fluoride (the cations of the alkaline-earth metals yield slightly soluble fluorides). 

Abstract A colloidal solution of titanium dioxide (TiO ) nanoparticles was prepared by the solvothermal method and dip-coated onto a polypropylene fabric with TMOS binder. The prepared TiO particles, colloidal solution and the coated fabrics were characterized by X-ray diffraction, SEM and TEM. The results showed that the TiO particles prepared by the solvothermal method were composed of anatase which uniformly coated the snbstrate. Photocatalysis induced bactericidal properties of coated fabrics were tested by measuring the viability of Escherichia coli. It was fonnd that solvothermally prepared TiO coatings have the ability to kill E. coli. This nniqne property of TiO makes it an ideal candidate in producing self-sterilizing protective masks and in providing bactericidal and self-cleaning properties to a variety of snrfaces. 

Experiments were performed using a titanium sapphire laser oscillator capable of producing pulses with bandwidths up to 80 nm FWHM. The output of the oscillator was evaluated to make sure there were no changes in the spectrum across the beam and was compressed with a double prism pair arrangement. The pulse shaper uses prisms as the dispersive elements, two cylindrical concave mirrors, and a spatial light modulator (CRI Inc. SLM-256), composed of two 128-pixel liquid crystal masks in series. The SLM was placed at the Fourier plane [5]. After compression and pulse shaping, 200 pJ pulses were used to interrogate the samples. 

In order to prevent the reduction between iron(II) and formaldoxime occurring, another iron complexing agent (potassium cyanide) was used in the presence of a reductant (ascorbic acid) that reduces iron(III) to iron(II). Aluminium, titanium, uranium, molybdenum and chromium also form light-coloured complexes that normally do not interfere in the determination of manganese in water or plant material by this method. If the aluminium or titanium concentrations are higher than 40 ppm an additional masking flow of tartrate is recommended [31]. 

A 5.5 (xm photoresist layer was patterned as the sacrificial layer, followed by the deposition of a second 4.5 p,m parylene layer. The parylene/photoresist/ parylene sandwich structure formed the electrospray nozzle and channel when the photoresist was subsequently dissolved. A 1500 A sputtered aluminum layer was used as a mask for parylene etching to define the shape of the nozzle. Aluminum was removed by a wet etching process. After SU-8 developing, wafers were left inside the SU-8 developer for 2 days to release the photoresist. A serpentine channel (250 pan x 500 pm x 15 mm) extending from the junction of pump channels to the edge of the chip was patterned in the SU-8 layer. Platinum/titanium lines spaced 200 pm apart were patterned under the channel after the electrode deposition step. 

FIGURE 2.31 Glass substrates before and after etching by 48% HF when the etch masks are (a) sputtered Ti (50 nm)/Au (200 nm) and (b) sputtered-gold titanium passivated with electroplated gold [123], Reprinted with permission from the Institute of Physics Publishing. 

A sequence involving a titanium-catalyzed hydroamination of alkynes, followed by an intramolecular N-arylation of the resulting imines, has been implemented in an approach to indoles, allowing, for example, efficient conversion of the substrate 472 into the indole 473, which incorporates a masked amine functionality (Equation 131) <2003AGE3042>. 

The potassium complex of the hydroxyethyl functionalised carbene, once formed, can then be used as a carbene transfer agent. Patel et al. employed this compound in the synthesis of titanium(lV) complexes used as catalysts in the polymerisation of lactides [38]. Synthesis of the catalyst is facile and involves the reaction of the potassium complex of the hydroxyethyl functionaUsed carbene with [TiCOFV) ] (see Figure 4.7). Although the activity of the titanium(lV) carbene complex is considerably less then that of the potassium complex, the titanium complex acts as a masked NHC and thus a highly moisture and air stable NHC source [38]. 

An alternate approach to these useful 1,3-dicarbonyl substrates may be achieved through enolate orthoester acylation. Titanium enolates have been employed to effect this transformation (eq 19). Similarly, treatment of the titanium enolate of p-ketoimide with dioxolane orthoesters results in the formation of a masked tricarbonyl compound (eq 20). Trimethyl orthoacetate and Triethyl Orthoacetate are not appropriate partners in these coupling reactions. ... 

Masking creams (camouflaging preparations) for obscuring unpleasant blemishes from view are greatly valued by the victims. They may consist of titanium oxide in an ointment base with colouring appropriate to the site and the patient. 

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