Specialized Measurements

Availability of high-brilliance synchrotron-based X-ray sources, progress in X-ray focusing optics, and fast 2D large-area detectors have made it possible to carry out measurements at submicron spatial resolutions and at 

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Dry-Film Resists Based on Radical Photopolymerization. Photoinitiated polymerization (PIP) is widely practiced ia bulk systems, but special measures must be taken to apply the chemistry ia Hthographic appHcations. The attractive aspect of PIP is that each initiator species produced by photolysis launches a cascade of chemical events, effectively forming multiple chemical bonds for each photon absorbed. The gain that results constitutes a form of "chemical amplification" analogous to that observed ia silver hahde photography, and illustrates a path for achieving very high photosensitivities. 

The shaping of these fine, submicrometer powders into complex components and their subsequent consoHdation into dense ceramic parts of ideally zero porosity is a major technological challenge. The parts formed need to be consoHdated to near-net shape because Si N machining requires expensive diamond grinding. Additionally, Si N dissociates at or near the typical densiftcation temperatures used in the fabrication of stmctural ceramics and, therefore, special measures have to be taken to preserve the compositional integrity of the material. 

The occurrence of pitting seems to stem from the differential stabiUty of the passive film that forms on the titanium alloy. This film does not break down uniformly even when the electrolytes are fluoride and bromide based. The pitting can be so severe that special measures are needed to counteract it. 

Ceiling value and skin absorption special measures to prevent significant cutaneous absorption may be required. 

Point (a) only concerns simple metal electrodes and needs to be tested for each case. Point (b) is important for the measuring instrument being used. In this respect, polarization of the reference electrode leads to less error than an ohmic voltage drop at the diaphragm. Point (c) has to be tested for every system and can result in the exclusion of certain electrode systems for certain media and require special measures to be taken. 

Buried steel pipelines for the transport of gases (at pressures >4 bars) and of crude oil, brine and chemical products must be cathodically protected against corrosion according to technical regulations [1-4], The cathodic protection process is also used to improve the operational safety and economics of gas distribution networks and in long-distance steel pipelines for water and heat distribution. Special measures are necessary in the region of insulated connections in pipelines that transport electrolytically conducting media. 

Chemoinformatics (or cheminformatics) deals with the storage, retrieval, and analysis of chemical and biological data. Specifically, it involves the development and application of software systems for the management of combinatorial chemical projects, rational design of chemical libraries, and analysis of the obtained chemical and biological data. The major research topics of chemoinformatics involve QSAR and diversity analysis. The researchers should address several important issues. First, chemical structures should be characterized by calculable molecular descriptors that provide quantitative representation of chemical structures. Second, special measures should be developed on the basis of these descriptors in order to quantify structural similarities between pairs of molecules. Finally, adequate computational methods should be established for the efficient sampling of the huge combinatorial structural space of chemical libraries. 

Pasquill (11) advocated the use of fluctuation measurements for dispersion estimates but provided a scheme "for use in the likely absence of special measurements of wind structure, there was clearly a need for broad estimates" of dispersion "in terms of routine meteorological data" (p. 367). The first element is a scheme which includes the important effects of thermal stratification to yield broad categories of stability. The necessary parameters for the scheme consist of wind speed, insolation, and cloudiness, which are basically obtainable from routine observations (Table 19-3). 

Often special measures are taken to ease cake discharge and enhance filtration. The measures taken include precoating and the addition of body aid. Precoating the plates prior to introducing the feed is done only in the following cases ... 

Cake disposal is relatively straightforward. Cakes may be discharged into bins that are trucked away or transported with a belt conveyor. With very large filter presses a well formed cake may weigh 200-300 kg per chamber and when it falls into a bin or onto a belt conveyor in one solid piece the impact is very high. Hence, special measures are required to break and de-lump the sole hard cake and, for belt conveyors, it is also recommended to increase the number of belt support rollers below the discharge chute at the point of impact. 

The old, tedious, but quite reliable method is to measure the supply flow by the bag method. A tightly rolled plastic bag empty of air at the commencement of the test is pressed on the terminal with all the supply air passing into the bag. The filling time of the bag is measured and the flow rate calculated based on this information. The bag volume has to be determined in advance by a special measurement. Finally, the characteristic pressure difference method, menrumed above, can also be applied to supply terminals. 

Figure 49 shows that porphynns are decomposed in the layer within a few hours if no special measures are taken, but that they can be stabilized for more than 24 hours if the layers are dipped m 50% paraffin solution and stored in the dark. This was true of all six porphynns investigated (Fig. 52). Quantitation should not be undertaken less than an hour after dipping the chromatograms, because it takes so long for the fluorescence emission to stabilize [230].

Do provide set-up instructions and diagrams for making special measurements. 

Special measures are required for certain chemicals diat are transported by road. The following classes of substances, wliich liavc been prohibited for transport by road in substantial quantities in West Gerniiiiiy since 1971, indicate some of the cheniiccils regarded as particularly hazardous, which dierefore require special measures for transport. ... 

More recently, further developments have shown that the reaction outlined in Scheme 4.33 can also proceed for other alkenes, such as silyl-enol ethers of acetophenone [48 b], which gives the endo diastereomer in up to 99% ee. It was also shown that / -ethyl-/ -methyl-substituted acyl phosphonate also can undergo a dia-stereo- and enantioselective cycloaddition reaction with ethyl vinyl ether catalyzed by the chiral Ph-BOX-copper(ll) catalyst. The preparative use of the cycloaddition reaction was demonstrated by performing reactions on the gram scale and showing that no special measures are required for the reaction and that the dihydro-pyrans can be obtained in high yield and with very high diastereo- and enantioselective excess. 

Figures 19.62 and 19.63 were taken at the time of investigation into a failure of 1001 of steel which should have been coated with a nearly maintenance-free system. Zinc metal spray and four coats of paint were specified but, for reasons of economy, special measures for inspection were not taken. Within months of erection areas were flaking off where millscale had not been removed (Fig. 19.62) and other areas were blistering. Figure...

Special measures to reduce coating damage during handling, transport or erection and measures for maintenance of incomplete systems stored in the open. 

Yet pressing is an all too unproductive method and cannot be used as the main manufacturing process. Therefore special measures are to be taken to minimize the crushing of filler in composite filled with lamellar or fibrous materials. 

The disadvantage of the two-phase contacting principle is related to the technical expenditure of realizing phase separation throughout the complete reactor passage. Special measures have to be taken to prevent phase inter-mixing. Also, this has to be controlled during the process. Hence inspection windows are essential (for the first prototype they may be eliminated later). 

The resultant force F is compensated by the reaction of the thread and, correspondingly, it does not influence the motion of the mass. In general, the total torque T has arbitrary direction, but we will be interested in only its vertical component, that causes a rotation in the horizontal plane. At the same time special measures are taken to remove an influence of motion in the vertical plane. 

No special measures are required but the reaction mixture should not be held under heat accumulation conditions for longer time. 

Flow injection analysis (FIA) (Ruzicka and Hansen), since 1975 In continuous flow, stopped flow or with merging zones (FIA scanning or intermittent pumping) Adapted voltammetric electrodes Membranes for Partial dialysis Membrane amperometry (Clark) Differential techniques (Donnan) Computerization, including microprocessors Special measuring requirements in plant control (to avoid voltage leakage, etc., Section 5.5)... 

The accuracy needed depends on the use to which the data will be put. Before spending time and money searching for the most accurate value, or arranging for special measurements to be made, the designer must decide what accuracy is required this will depend on several factors ... 

FSO - Full Scale Output Special measuring ranges... 

Therefore, governmental authorities and local public health bodies need to apply great material, technical and physical efforts on taking a number of special measures to eliminate consequences of the act of chemical terrorism. 

Fig. 1.49. NMR analyzer NMS 120 minispec from the NMS 100 minispec serie. Measurements below room temperature require a special measuring head, which is cooled by a cryostat (photograph Bruker, Analytische MeBtechnik GmbH, D-76287 Rheinstetten, Germany).

Technical support for any special measurements such as necropsy, hematology, urinalysis, and clinical chemistry must be available on the dates specified in the protocol. 

A variation on this is to stagger the start-up either of different dose groups, or of the satellite and main study portions of dose groups. The former is to be avoided (it will completely confound study outcome), while the latter makes sense in some cases (pharmacokinetics and special measures) but not others (recovery and interval sacrifice). 

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