Plastic cleaning

Prior to smelting, batteries are usually broken up and sorted into their constituent products. Fractions of cleaned plastic (such as polypropylene) case are recycled into battery cases or other products. The dilute sulfuric acid is either neutralized for disposal or recycled to the local acid market. One of the three main smelting processes is then used to reduce the lead fractions and produce lead bullion. 

The recycled plastic will also have a degree of different contaminants that would eliminate its use in certain devices or products, such as in medicine, electronics, and food packaging. However, within these market applications there are acceptable designs with three-layer coextruded, coinjected, or laminated structures having the contaminated plastic as the center layer, isolated by clean plastics around it and no migration occurring. 

Recommends storing equipment parts in clean plastic bag or container. 

Mechanical recycling is the preferred route for homogeneous and relatively clean plastics waste streams. It is assumed that the cushion vinyl floor covering will be mechanically recycled [11].1... 

Add 100 J L of IX PCR reaction buffer on the top of the each slide, cover the tissue with either a clean plastic or a glass cover slip, and seal with rubber cement (see Notes 18 and 25). 

Large beaker or clean plastic bucket String with a label attached Aluminum foil... 

Trace analysis has its special hazards for the unwary. The most important of these are loss of material in the analytical process and contamination by outside sources. Everyone realizes that trace constituents can be lost from samples, but few are aware of the many ways in which this can occur. For example, phosphate has been observed to disappear mysteriously from water samples in polyethylene bottles (10). Nitric acid, used to clean plastic vials, has been observed to convert these surfaces to ion exchangers, which readily take up as much as 10 12 moles per sq. cm. of trace metals (16). Lead nitrate solutions unless made distinctly acidic, plate out much of the lead on the walls of glass bottles. While everyone realizes that formation of a precipitate is liable to carry out trace constituents either by adsorption or occlusion, it is not as well-known that vanishingly small amounts of precipitates—amounts likely to be overlooked on casual observation—may also do this. The fly-ash and soot, which seem to be inescapable components of city air,... 

Once the sample has been homogenized, carefully transfer the sample into the Kraft bags using a clean plastic funnel. 

Solutions containing Sbm and Sbv in deionised water at 0°C and 25°C in polyethylene containers were stable for 1 year (De la Calle Guntinas and Camara, 1992). However, samples of natural water, acidified to pH 2 or less, required rapid freezing to -4°C to avoid oxidation of Sbm. In anoxic seawater, concentrations of antimony species (Sbm and Sbv) in stored samples were about 49% lower than those determined at sea soon after the samples had been obtained (Cutter et al., 1991). Samples of particulate material were placed in acid-cleaned plastic bags or vials and then preserved by freezing. 

Inorganic arsenic species, As111 and Asv, in natural water and anoxic seawater samples were not stable (Cutter et al., 1991). Rapid freezing and storage at —4°C was recommended as a means of preservation. Particulate samples were collected in acid-cleaned plastic bags, and then frozen. 

Set 2, 1 ml of KH2P04 containing 250 tg P ml1 is added and mixed gently. The soils are carefully added to the flasks, rinsing in any soil residues. A set of at least three blanks is included for each full run. The mixtures are shaken for 30 minutes at 25°C on an orbital shaker (30 minutes, 150 rpm) and then are filtered (fluted Whatman 42) into clean plastic bottles. 

Step 11. Elute the strontium from the column with two 5-mL portions of 0.5 M HN03. Collect the two eluents in a clean plastic container (a 20-mL liquid scintillation counting vial or a 50-mL centrifuge tube is suitable). 

As a general rule, samples should be collected in decontaminated flasks and even those considered metal-free should be pre-washed. Glass recipients should be avoided. A good procedure for cleaning plastic containers is keeping them at least 24 h in a 10% (v/v) ethanolic nitric acid solution. Aqueous solutions do not leach out the aluminum well, because water does not wet plastic surfaces better contact occurs when an alcoholic solution is used. It can be seen that all alcoholic solutions were more efficient than the aqueous solutions. Table 10 shows the aluminum extracted from polyethylene by the action of some washing solutions. Just before use, the containers should be abundantly washed with ultrapure water. The best option is to use the flasks just after rinsing them, however if they must be dried, they should not be placed in an oven, even with the open side on tissue paper (paper contains aluminum). The best way is let them dry under a laminar flow. The proper heat and air movement inside the hood will help to rapidly dry the flasks. 

L or 2 L clean plastic soft drink or juice bottle round balloon pointed scissors... 

Thin slices of tissue are placed in clean plastic petri dishes, the loose fitting lids replaced and the dishes inserted into the chamber of the freeze drier. Blood specimens can be poured directly into the dish. It is important that the tissue be thoroughly frozen prior to evacuating the chamber. The time required for complete drying of the sample depends on the nature and weight of the material and the type of equipment employed. Drying is usually completed in 12—48h. The dried tissue is not susceptible to decay and can be stored at room temperature in sealed plastic bags. 

The buffer was prepared by dissolving 100 g of sodium dihydrogen phosphate monohydrate (Alfa Johnson Matthey) into 200 mL of glass-distilled water. The pH of the solution was adjusted to 6.9 with the addition of concentrated sodium hydroxide solution (MC8 Reagent) and verified with a pH meter recently calibrated between 4-7 pH units using Fisher standards. The buffer solution was diluted to a final volume of 500 mL (i. 45 M) and stored in a clean plastic bottle. 

Fill one of the clean, plastic containers with water. The water should come to the top brim of the container. 

Deep hand-dug pits are used to collect clean samples down to a depth of 10-15 m. Using appropriate clean-room clothing and ultra-clean shovels and tools (28), operators may dig pits and collect various sized blocks (28, 29) or several samples by pushing ultra-clean plastic cylinders horizontally into the walls, from the surface to the bottom of the pit (27, 30). 

For deeper samples, collected in the form of snow and ice cores, contamination is more or less always present. In this respect, decontamination of the snow and ice cores is of paramount importance in order to give reliable results. Decontamination consists of eliminating the contaminated outside concentric layers and recovering the presumably uncontaminated inner core. This really important operation has to be carried out in strict accordance to clean room protocols (2, 6, 27, 29, 34, 35). Usually, the ice core to be decontaminated is fixed horizontally on a LDPE speed lathe under a high purity air laminar flux, in a cold room at -15°C (6, 34). Beginning from the outside and moving towards the center of the core, successive veneers of ice are chiseled by a series of ultra-clean plastic or stainless steel knives depending on the hardness of the snow or ice the material obtained is collected in ultra-clean LDPE bottles and then analyzed to quantify the trace element content. Usually, three-four outer layers and one inner ice core can be obtained. 

Collect leaf samples. These can be from trees near a road or highway and from some that are more isolated for comparison. Collect at least two large leaves from each tree and place each in a clean plastic bag and seal. The leaves selected should be reasonably free from dirt or other visible contamination. Record the location of the leaves. Your instructor will advise you of the number of trees you should sample. 

A sample should be prepared properly and then placed in a container before it is irradiated. The person who prepares the sample should be extremely careful not to contaminate it. Activation analysis is so sensitive that it can determine traces of elements undetectable by chemical methods. If the sample is left on a table for a certain period of time, it collects dust that acts as a contaminant. Touch by hand may transfer enough salt to cause the irradiated sample to show the presence of sodium and chlorine. To avoid contamination, samples should be handled in dry boxes or in clean rooms. The person who prepares the sample should use clean instruments (knife, file, tweezers, etc.) and also wear clean plastic gloves. 

Use cleaned plastic collection tubes with stoppers. The whole set (tube and stopper) must be tested to deliver less than 10% extraneous amounts of cadmium. Do not use coloured stoppers. Do not use plastics with a Cd-softener. Before starting the study test 6 test tubes per tube production lot. During the study frequently test blank tubes, e.g. for 1% of the total number of samples to study. Test may be performed with a 1% v/v solution of nitric acid (e.g. Suprapur quality) in bidistilled water. Preferably use vacuum collection tubes. No special type of needles is required. Needles of stainless steel are adequate. Other needles, e.g. siliconized or iridium needles may be used as well but are not necessary. Use vinyl gloves, free of talc. Use cleaned plastic test tubes. See further collection tubes. Do not use glassware. 

Pipette 50 pi 2-mercaptoethanol, 950 pi 2x Tris-glycine SDS-loading buffer and 1 ml TPERTM into a clean plastic tube. Mix well. 

Prepare 20 ml of lx desalting buffer for each sample by diluting lOx desalting buffer with the appropriate volume of Milli-Q-grade H20. Store lx desalting buffer in a clean plastic mbe. Note Be sure that lx desalting buffer has a pH =... 

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