Discontinuously application

Recently, the electrochemical reduction of sulfur dyes was studied. For continuous processes a mediator is not necessary. In discontinuous application it is possible to reuse dyebaths [72],... 

If the sample is applied as a spot, it splits up into a series of spots which lie farther apart as the time interval grows longer. This method with discontinuous application of the sample is called star electrophoresis because of the appearance of the stained substrate (P4). 

A last remark must be made about the use of the word continuous electrophoresis, covering collecting two-dimensional techniques in which both sample and background buffer feeding are continuous. As there is a two-dimensional technique with discontinuous application of the sample but a continuous feeding of buffer, the use of the term continuous is difficult, and again the terms collecting and star electrophoresis are preferred. 

Discontinued applications. The use of phenylmercuric acetate as a fungicide in interior latex paints was banned in 1990 (Reese 1990), and its use in exterior paint was banned in 1991 (Hefflin et al. 1993). Both of these bans were prompted because of releases of mercury vapors as the paint degraded. Alkyl mercurial compounds were used until the mid-1970s as a treatment to disinfect grain seeds. Most other agricultural applications of mercury compounds in bactericides and fungicides have been banned due to the toxicity of mercury. Mercuric nitrate was used in the production of felt hats to hydrolyze rabbit fur. The use of mercury as a wood preservative has ceased due to the use of polyurethane (Drake 1981). 

Purification can be accomplished by varied means and there is no one best way to handle all situations. In projecting a new venture to operation on the industrial scale, one should be acquainted with established industrial practices. For this there is no need to describe each separate type of factory operation, inasmuch as many incorporate similar processing methods and a full recital would bog down in tedious repetition. Therefore the discussion here will be limited to a description of representative applications selected to illustrate different means for accomplishing diverse objectives. Included are processes in current industrial use together with items taken from pilot plant studies. Several discontinued applications are included because they contain potentially useful techniques not reported elsewhere. 

The few publications which discuss the action of peracetic acid against drinking water or wastewater biofilms suggest that practice-relevant concentrations of peracetic acid cause a relatively fast and effective inactivation of biofilm bacteria, but result in no or minimal removal of the biofilm under these conditions. This is considered to be a disadvantage for at least the drinking water area, where residual biofilm material on surfaces can promote recontamination of the water (Exner et al., 1987 Morin, 2000). In this context, Mathieu et al. (1990) reported that the discontinuous application of peracetic acid led to an incomplete disinfection and dissolution of biofilms, but nevertheless can significantly limit the extent of biofilm development. 

These hot spots are less troublesome as the concentration is decreased. In our experience, we have gone from 45%, to 35%, to 25%, to 15%, and, now, to 7.5% TCA. We discovered during these dilutions that the results with TCA are coat dependent. Whereas, the results with alpha hydroxyl acids are time-dependent, and phenol results are cardio-dependent, TCA results are dependent on the number of layers applied. The more coats that are used the deeper the peel, so multiple coats of a 15% TCA can mimic the results of one or two coats of 30% TCA. These dilute peels take more time and more coats - which is exactly what we want - so we have more time to watch the blanch develop and we can discontinue applications at a predictable foggy-red blanch. The weaker strengths of TCA give us more time to think. 

D. Lubach, J. Rath and M. Kietzmann, Steroid-induced dermal thinning discontinuous application of clobetasol-17-propionate ointment. Dermatology, 1992, 185, 44-48. 

It should be emphasized at this point that the basic requirements of compatibility and consistency of finite elements used in the discretization of the domain in a field problem cannot be arbitrarily violated. Therefore, application of the previously described classes of computational grids requires systematic data transfomiation procedures across interfaces involving discontinuity or overlapping. For example, by the use of specially designed mortar elements necessary communication between incompatible sections of a finite element grid can be established (Maday et ah, 1989). 

Loose asbestos fibers, or formulations containing asbestos fibers for spray coatings, have been widely used in the building industry for fire protection and heat or sound insulation. Such applications used mainly chrysotile or amosite but, because of health concerns, this practice has been discontinued. 

Additional theoretical bac-kground can be obtained from Preiswerk, Application of the Methods of Gas Dynamics to Water Flows with Free Suiface, part 1 Flows with No Energy Dissipation, NACA Tech. Mem. 934, 1940 part 11 Flows with Momentum Discontinuities Hydraulic Jumps), NACA Tech. Mem. 935, 1940. 

The introduction of Lagrangian coordinates in the previous section allows a more natural treatment of a continuous flow in one dimension. The derivation of the jump conditions in Section 2.2 made use of a mathematical discontinuity as a simplifying assumption. While this simplification is very useful for many applications, shock waves in reality are not idealized mathematical... 

Changes to environmental computer applications occur rapidly, therefore, the list cannot remain current. New systems are being developed, vendors move or go out of business, and identified systems are being updated, sold to other vendors, tailored to new markets, or discontinued. 

Application of this procedure to inadvertently ignited safety valve discharges can involve a special problem. Certain combinations of pressure ratio and length of safety valve riser can result in choked flow, with a pressure discontinuity at the exit. The pressure of the jet then adjusts to atmospheric pressure in a system of shock waves or expansion waves over a distance of a few pipe diameters. These waves can affect the local mixing of the jet with the crosswind. Since the calculation procedure incorporates correlations for subsonic jets, it cannot be expected to be entirely accurate in this case. Nevertheless, since the wave system... 

A drawback of the Lagrangean artificial-viscosity method is that, if sufficient artificial viscosity is added to produce an oscillation-free distribution, the solution becomes fairly inaccurate because wave amplitudes are damped, and sharp discontinuities are smeared over an increasing number of grid points during computation. To overcome these deficiencies a variety of new methods have been developed since 1970. Flux-corrected transport (FCT) is a popular exponent in this area of development in computational fluid dynamics. FCT is generally applicable to finite difference schemes to solve continuity equations, and, according to Boris and Book (1976), its principles may be represented as follows. 

Radiographic Examination. Main load carrying components of the equipment shall be examined by means of gamma rays or x-rays. The procedure used shall be in accordance with applicable ASTM standards. Types and degrees of discontinuities considered shall be compared to the reference radiographs of ASTM as applicable. The extent of examination and the basis for acceptance shall be agreed upon by the manufacturer and purchaser. 

Specific application for machines with combined hydraulic and plain bearings, and lubrication systems where discontinuous or intermittent sliding (stick-slip) at low speed is to be prevented... 

The desire to replace cadmium is generally attributed to its toxicity, both in terms of process pollution and product corrosion, and several alternatives are feasible thicker zinc, tin-zinc alloy or tin-nickel alloy depending upon the precise application " . The demise of decorative nickel-chrome systems in the automotive industries of the world is partly due to cost and partly to market image, and not to technical performance where major improvements took place in the period 1960-1975 through the establishment of duplex nickel under-layers and micro discontinuous chromium top-layers. In the 1980s the trend has been towards black finishes produced generally by powder-applied epoxy polymers. 

Besides its usage in foods, indene polymer is used in the coatings industry, inks, floorings and in rubber applications. Some use has been made of the nitrated polymer as an ingredient in fuze powder (substituting for charcoal), but because of the sensy to impact this use is discontinued (Ref 3)... 

Perhaps the most significant recent issue for the industry was the phase-out of CFCs as blowing agents resulting from the Montreal Protocol (1987) and Clean Air Act (1990).19 These regulations mandate specific timelines for discontinuation and, since foams comprise the bulk of polyurethane applications, have prompted a worldwide search for alternatives. Hydrochlorofluorocarbons, HFCs, and hydrocarbons (HCs) are now the blowing agents of choice. Which one is... 

This method of solution of problems of unsteady flow is particularly useful because it is applicable when there are discontinuities in the physical properties of the material.(6) The boundary conditions, however, become a little more complicated, but the problem is intrinsically no more difficult. 

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