Internal filtering

Filtered valves contain a fine internal filter, typically below the body orifice. This filter prevents clogging by the debris sometimes found in product and package. The use of filtration is recommended with any valve systems containing body, stem, or actuator orifices of 0.25-mm (or smaller) diameter unless exceptional care is taken in the cleaning of product and package components. Valves containing these small orifices are used for products propelled by compressed gas. 

Stokes Vacuum, Inc. Price includes dryer, 15-lVin jacket, drive with motor, internal filter, and trunnion supports for concrete or steel foundations. Horsepower is established on 65 percent volume loading of material with a hulk density of 50 Ih/ft. Models of 250 ft, 325 ft, and 400 ft have extended surface area. 

For filter boxes, provide internal filter box ventilation... 

Design internal filter ventilation for excessive flammable vapors... 

Booths are also available that recirculate the exhaust air, after internal filtering, to the surrounding room or other areas outside the room. 

Using an Andersen sampler, total counts of airborne BCFP ranged from 3 to 7 (/103) close to pigs. In general, values increased 3-fold as the pigs grew from 3 weeks to 7 weeks old and halved when internal filters were installed. 

Assays for endo-l,4- -glucanase [EC 3.2.1.4] (i.e., CMCase) and saccharifying cellulase (i.e., international filter paper U, IFPU) activities partially followed the methods recommended in the 1987 lUPAC report (65). When even undiluted enzyme samples fail to give the required glucose yield under prescribed assay conditions, the lUPAC committee recommends a less precise method. In the current study, cellulase activities in digester extracts were so low that the CMCU could only be defined as follows one CMC unit of activity was that amount of enzyme required to liberate one Hg glucose from CMC in 60 min. 

International filter paper cellulase activity unit. hiang, M. Linden, J.C. Mohagheghi, A. Grohmann, K. Himmel, M.E. AppL Microbiol TechnoL, submitted. 

Caldwell, M.M., Robberecht, R., and Flint, S.D., Internal filters prospects for UV-acclimation in higher plants. Physiol Plant., 58, 445, 1983. 

Figure 11.12 represents the main kinds of rotary drum filters. Commercial sizes are listed in Table 11.14. The fiowsketch of Figure 11.12(a) identifies the main auxiliaries required for this kind of filtration process. Feed to the drum may be dip-type as in Figure 11.12(b), but top feed designs also are widely used. The unit with internal filtering surface of Figure 11.12(c) is suited particularly to rapidly settling solids and has been adapted to pressure operation. 

In most cases two different additives are used, one acting as an internal filter or excited state quencher and the other one being a scavenger of free radicals. These two additives have a synergic effect, that is they are much more effective together than either of them separately. 

These molecules have no absorption in the near UV, so they cannot act as internal filters. There is no evidence that they could act as quenchers of the excited impurity chromophores in common polymers, and it has been mentioned already that such quenching action would be, in any case, unlikely to be important in relatively rigid systems such as polymers. This remark does not apply to free radical scavengers, because a free radical has an unlimited lifetime since it can disappear only through a chemical reaction with another open-shell molecule. 

Filter paper activity, which describes the overall cellulolytic activity of an enzyme preparation, was determined by the method of Mandels et al. (16). A 1 x 6 cm strip of Whatman no.l filter paper (Hillsboro, OR), which equals 50 mg of cellulose, served as the substrate and was added to the sample solution containing 0.5 mL of appropriate diluted enzyme (supernatant of culture broth) and 1.0 mL of 0.05 M citrate buffer (pH 4.8). After 60 min of incubation at 50°C, the hydrolysis was terminated by the addition of 3 mL of DNS solution, and the mixture was further assayed for reducing sugar content by the DNS method. One international filter paper unit (FPU) was defined as the amount of enzyme that releases 1 pmol of glucose/min under the assay conditions. Activities were reported as FPU/milliliter. 

Enzymes were supplied by Novozyme (US Office Franklinton, NC) and included cellulase (Celluclast 1.5 L 48 international filter paper units [IFPU]/mL), (3-glucosidase (Novozym 188 66.8 x 103 IU/mL), and glucoamylase (Novozyme AMG300L). Sugars were purchased from Sigma (St. Louis, MO), and all other chemical and media reagents were from Fisher (Fairview, NJ). 

Commercial cellulase and P-glucosidase (Novo Nordisk, Bagvaerd, Denmark) supplied from Novozymes Korea were used. A mixture of Celluclast (80 IU or international filter paper units [IFPU]/mL) and Novozym 188 (792 cellobiase units [CBU]/mL) was used with a ratio of 4 IU of Celluclast/CBU of Novozym to alleviate end-product inhibition by cellobiose. 

When the IR analyzer is used for in situ stack gas analysis, two different approaches can be used (1) the detectors and source on the same side of the stack, and (2) the detectors and source on opposite sides of the stack. For installation purposes, the first is much easier, but it requires an internal filter to remove any solids from the stream. In the second system, shown in Figure 3.8, both the reference and measuring wavelengths are affected by the same scattering bodies in the stream therefore, there is no need for a filter. This system is frequently used in pollution alarm applications. 

It can be seen that amounts of up to a few grams can be converted in 5-10 h in the case of complete absorption and unitary quantum yield (ignoring any internal filter effect). Lower quantum yields or an incomplete absorption proportionally lengthens the time required for the transformation. It is most likely safe to say that exploratory reactions on the 100 mg scale can be carried out in a reasonable time, provided that > 0.1-0.05. Even reactions with a quantum yield at the lower limit or below may be interesting for a preparation if the reaction is clean. Given the minimal safety... 

In aqueous alcohol or in dioxan a red dye is formed which acts as an internal filter and effectively stops the photoreaction. In ether photolysis produced only polymers, possibly via the radical (151)... 

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