Balled filter paper

Ruminococcus albus strain 7, (1), was grown on cellulose roll tubes according to the Hungate technique (2). Either Avicel (FMC Corporation, Marcus Hook, Pa.) or balled filter paper was used as the cellulose source. Three milliliters of melted cellulose-medium at 45 °C. in 16 X 150 mm. tubes were inoculated with the bacteria under a gas phase of 95% C02 and 5% H2. The tubes were subsequently stoppered and rolled in a tray of ice in order to form a film of agar medium around the... 

Cool the slurry to ca 50° and either centrifuge it or filter through a Buchner. Wash the balls with cold distd w to remove the protective colloid and Na sulfate, spread the proplnt on a filter paper and dry it... 

In a typical enzymatic hydrolysis of a 5% suspension of ball-milled newsprint, a sugar syrup containing 1.6% glucose, 1.4% cellobiose, and 0.2% xylose is readily obtained. Figure 3 is illustrative of kinetic results obtained with T. viride cellulase at 3.5-filter-paper-units/mL (FP units/ mL) strength in a 5% suspension of ball-milled newsprint. 

Isolation of Lecithin from Egg-yolk (section 217).— Grind the yolk of one hard-boiled egg with 50 cc. of ether. Filter and wash the solid residue twice with 10 cc. of ether. Evaporate off the ether on the steam-bath, or distil it off from a small flask. Extract the residue twice with hot alcohol, using 10 cc. each time. Pour off the alcohol from the heavy oil through a small filter. Evaporate off the alcohol, dissolve the residue in 10 cc. of cold ether, and add 10 cc. of acetone. Stir until the particles of the precipitated lecithin adhere together and form a ball. Place the latter on a filter-paper. Describe its properties. Boil about one-fourth of the lecithin with about 10 cc. of a 10 per cent solution of sodium hydroxide. Note the odor of the gas evolved. What is it Cool the solution. Is there any evidence of the formation of a soap Filter, dissolve the precipitate in warm water and add dilute hydrochloric acid to the solution. What is precipitated Test a part of the lecithin for nitrogen and for phosphorus ( 58, 59, 61, page 39). 

Free (wash) solution was removed from the filter with filter paper, positions A12 and HI marked with ball point (not a felt pen ). The filter was placed in a closely fitting box, 10 ml of substrate solution was added and incubated for 1 min. The filter was wrapped, straight from the substrate in plastic, without air bubbles. Liquid pressed out, the filter transferred in plastic into the luminometer cassette and placed in the luminometer. Luminescence was measured according to the required program. Data were collected in a file and for each sample the level of N7-HETE-dG/107 nucleotides was calculated (in an Excel worksheet). 

Cellulase is a complex of enzymes showing various types of activities. Cellulose substrates include highly resistant crystalline forms such as cotton, various types of microcrystalline cellulose such as Avicel and hydrocellulose, sulfite pulps such as Solka Floe, as well as filter paper and cotton fabrics. More susceptible substrates include swollen or reprecipitated cellulose, cellophane, and ball-milled cellulose. Most susceptible are the soluble derivatives (of low D.S.) such as carboxymethylcellulose and cellulose sulfate. It is not surprising that there are many assay methods to detect or measure cellulase (9). These methods differ markedly in sensitivity, and in cellulase components detected, depending on the substrate used, the effect measured, and the duration and conditions of... 

Procedure. A large drop of the test solution is mixed on a watch glass with stannous chloride (a great excess is to be avoided). On gently heating, the precipitate balls together. A drop of chromotropic acid is placed on filter paper followed by a drop of the clear solution from the watch glass. In the presence of titanium, a red-brown fleck appears. The precipitate, as well as the clear solution, may be placed on the filter paper, because the precipitate remains fixed and the solution diffuses away. If the moist portion is then spotted with chromotropic acid, a red-brown circle is formed. 

Test chemicals or chemical fractions can be dispensed from a variety of materials, depending on their volatility and solubility. Chemicals may be evaporated from such materials as glass rods or beads, metal surfaces, filter paper disks, cotton balls or wicks, rubber septa, polyethylene vials, glass capillary tubes, etc. It is important to ensure that the dispenser emits the compound at a fairly constant rate over the course of the assay. This may be more difficult for very volatile chemicals, thus, fresh dispensers uniformly prepared ahead of time may be required. This may be most important in the early stages of investigation where fractions of unknown composition and concentration are being used in a bioassay-driven fractionation scheme to isolate and, ultimately, identify specific chemical compounds eliciting particular behaviors. 

A widely used bioassay to assess the abilities of test chemicals to elicit attack by bees and wasps is to expose the test subjects to a mock attack by a threatening object. Such objects are constructed from a series of white and black balls or cubes placed near the colony. Test chemicals are usually applied to filter paper and placed in a natural airstream that carries the test chemical to the colony entrance. The ability of a test chemical to elicit attack is quantified by counting the number of test insects that attack the cubes or balls. Usually black objects receive more attacks than objects of other colors (Jeanne 1981 Kojima 1994). 

Superabsorbent polymers (SAPs) are polymers that can absorb and retain extremely large amounts of liquid relative to their own mass. In deionized or distilled water a SAP may absorb 50,000% its own weight of liquid, while in a 0.9% saline solution the absorbency can reach about 5000% its own weight. This compares to water absorbencies of 180%, 400%, 1050%, 1200%, and 1890% for the filter paper, facial tissue paper, soft polyurethane sponge, wood pulp fluff, and cotton balls respectively. 

Mixed-media filters, the subject of the last paper in this section, use three or more materials of different sizes and densities that intermix to form a filter grading from coarse at the top to line at the bottom in the direction of flow. Typical media used are coal, silica sand, and garnet sand. High oil- and solids-rcmoval efficiencies are obtained Design and application criteria are presented, and media fouling or mud-balling" is discussed... 

When several ounces of liquid have been collected, you can begin the extraction procedure. It is best to filter the liquid through a ball of cotton or glass wool prior to use. Paper filters absorb a lot of the liquid and tend to fall apart due to the corrosive nature of the fluid. 

The classical use of a micro filter funnel and folded paper or cotton wool always leads to loss of material and when a suction ball is used, the filtrate contains neither threads from the paper nor colloidal portions of the clarifying agent. If the solute crystallizes in the suction ball during or after filtration, then, when filtration is complete and the filter end has been cut off, the suction ball is heated in a bath with the open capillary upwards until the crystals have redissolved. 

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