Can The Climate Tube Be Fully Immersed In Cleaning Solution

Ultrasonic Cleaning

Specifically, ultrasonic cleaning is performed using an organic solvent and ultrapure water to remove fine particles and organic substances fastened to the device.

From: Sample Return Missions , 2021

Extraction Techniques and Applications: Food and Beverage

D. Pingret , ... F. Chemat , in Comprehensive Sampling and Sample Preparation, 2022

iv.19.3.2 Instrumentation

The most mutual ultrasound equipment for extraction purposes are the ultrasonic cleaning bath and the probe system. For small extraction volumes, an ultrasound horn with the tip submerged in the fluid tin can be sufficient. Large volumes of fluids take to be sonicated in an ultrasound bath or in continuous or recycled-flow sonoreactor ( Figure 7).

Figure 7. Types of UAE appliance.

The coupling of the UAE to the analytical steps, which would overcome the dilution effect prior to analysis, has non been performed yet, despite its ease of implementation. The extract is then driven to the continuous manifold for on-line accomplishment of the belittling procedure, which involves preconcentration, derivatization, filtration, and detection (using flame atomic-absorption spectrometer (FAAS), gas chromatography-mass spectrometry (GC-MS), or other techniques).

While most of the research efforts in UAE take been centered around the ultrasound itself, some studies take also examined the coupling between ultrasound and other techniques. For instance, UAE is being employed in combination with microwave energy, ^nineteen supercritical fluid extraction, ²⁰ or just with conventional methods such as Soxhlet extraction. ²¹ When combined with supercritical fluid extraction, UAE enhances the mass transfer of the species of interest from the solid phase to the solvent used for extraction. Soxhlet extraction can also be improved by ultrasound when applied at the cartridge zone before siphoning, thus permitting the removal of lipid fractions from very compact matrices. The efficiency of combining microwave and ultrasound has been clearly shown in applications such as the extraction of copper and the Kjeldahl method for conclusion of total nitrogen in nutrient. ²²

Of import concrete parameters related to UAE are presented in this section. Ultrasound power, temperature, and extraction time affect not but the extraction yield but also the composition of the excerpt. The extractable molecules from food samples (secondary metabolites) are usually located inside vacuoles/glands that are inside the cell, therefore inside the cell walls. Since solid–liquid extraction is the passage from the soluble molecules into the solvent, comprising the phases of desorption, diffusion, and solubilization, the extraction recovery is adamant by one or several steps. Ultrasound has focused its power, at the showtime of extraction, on cuticular layer destruction and oil exudation. Then, it deflected this power against prison cell wall perforation mainly due to the high resistance of the particles in the medium toward ultrasound energy. When the glands were subjected to more severe thermal stresses and localized high pressures induced by cavitation, equally in the case of UAE, the pressure level buildup within the glands could take exceeded their chapters for expansion, and acquired their rupture more apace than in the control experiment.

A higher temperature for UAE might upshot in a higher efficiency in the extraction process due to an increase in the number of cavitation bubbling and a larger solid–solvent contact area. ²³ However, this effect is decreased when the temperature is nearly the solvent'south boiling bespeak. It is too important to forestall the deposition of thermolabile compounds. The ultrasonic power is one of the parameters to optimize in club to achieve a compromise between extraction fourth dimension and solvent volume. Mostly, the highest efficiency of UAE, in terms of yield and limerick of the extracts, tin be achieved by increasing the ultrasound ability, reducing the wet of food matrices to enhance solvent–solid contact, and optimizing the temperature to permit a shorter extraction time. The almost commonly used frequencies in sonochemistry are between xx and xl kHz. With higher frequencies, cavitation would be more hard to induce, since the cavitation bubbles need a lilliputian filibuster to be initiated during the rarefaction cycle. The higher the frequency, the less the rarefaction cycle lasts, then the less the chance of bubbles being created.

Cavitation bubbles not only consist of vacuum just as well contain some vapor of the liquid in which it is formed. If no gas is present in the liquid, bubbles would be dramatically more than difficult to be created. Dissolved gases in the solvent would act equally nuclei for a new cavitation bubble, and so this would increase the rate of cavitation bubble formation. On the other mitt, as the cosmos of the cavitation bubbles is facilitated, they would abound faster and the solvent might undergo humid: if the bubbles abound besides fast, they would non have time to collapse and the liquid would eddy without cavitation. The easy generation of bubbles in a liquid that contains a high content of dissolved gasses explains why ultrasonic baths are used for degassing liquid.

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Sonoluminescence and Sonochemistry

Kenneth S. Suslick , in Encyclopedia of Physical Science and Technology (Third Edition), 2003

III.A Experimental Design

A multifariousness of devices have been used for ultrasonic irradiation of solutions. There are 3 general designs in use soon: the ultrasonic cleaning bath, the direct immersion ultrasonic horn, and menstruum reactors. The originating source of the ultrasound is by and large a piezoelectric material, usually a pb zirconate titanate ceramic (PZT), which is subjected to a high AC voltage with an ultrasonic frequency (typically 15 to l  kHz). For industrial use, the more robust magnetostrictive metal alloys (usually of Ni) tin can be used every bit the cadre of a solenoid generating an alternating magnetic field with an ultrasonic frequency. The vibrating source is fastened to the wall of a cleaning bath, to an amplifying horn, or to the outer surfaces of a menses-through tube or diaphragm.

The ultrasonic cleaning bathroom is clearly the most attainable source of laboratory ultrasound and has been used successfully for a variety of liquid-solid heterogeneous sonochemical studies. The low intensity available in these devices (≈i   Westward/cm²), nonetheless, means that even in the example of heterogeneous sonochemistry, an ultrasonic cleaning bath must exist viewed as an apparatus of limited capability. The most intense and reliable source of ultrasound generally used in the chemic laboratory is the directly immersion ultrasonic horn (50 to 500   Westward/cmⁱⁱ), as shown in Fig. 10, which can be used for work nether either inert or reactive atmospheres or at moderate pressures (<x atmospheres). These devices are available from several manufacturers at pocket-size cost. Commercially available flow-through reaction chambers that will attach to these horns allow the processing of multi-liter volumes. The acoustic intensities are easily and reproducibly variable; the acoustic frequency is well controlled, admitting fixed (typically at 20   kHz). Since power levels are quite loftier, counter-cooling of the reaction solution is essential to provide temperature command. Large-calibration ultrasonic generation in flow-trough configurations is a well-established technology. Liquid processing rates of 200   L/min are routinely accessible from a diverseness of modular, in-line designs with acoustic power of ≈20   kW per unit. The industrial uses of these units include (ane) degassing of liquids, (2) dispersion of solids into liquids, (iii) emulsification of immiscible liquids, and (iv) big-scale cell disruption.

FIGURE 10. A typical sonochemical apparatus with straight immersion ultrasonic horn. Ultrasound tin can exist easily introduced into a chemic reaction with skilful control of temperature and ambient atmosphere. The usual piezoelectric ceramic is PZT, a lead zirconate titanate ceramic.

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Equipment used in cleaning

John Durkee Ph.D., P.Eastward. , in Direction of Industrial Cleaning Technology and Processes, 2006

7.ten.8 Replication Tin Be Hard to Reproduce

Functioning of sonic-powered cleaning system, for a given set up of parts, is related to much more than the choice of frequency and sweep rate, tank size, and power level. Chemicals, and their concentration, used in the operation can affect performance.

Merely at that place are other factors which can be significant, or not, which are non and so obvious. Some observed past this author are:

•

Tank configuration – depth ⁹⁹ versus open expanse. ¹⁰⁰

•

Tank configuration – presence of unusual shapes where waves aren't reflected back onto parts.

•

Positioning (racking) of parts within the open volume of a tank.

•

Location of transducers within a tank.

•

Operating temperature.

•

Residual gas (air ¹⁰¹ ) content.

•

Water quality. ¹⁰²

•

Smoothness of the part surface. ¹⁰³

•

Fluid circulation ¹⁰⁴ inside the tank.

•

Waveform of the ultrasonic-produced pressure pulses.

•

Anything present on the part surface which would prevent information technology from being wetted (and submerged).

•

Aggregating of debris within the tank.

Information technology isn't that ultrasonic cleaning in static tanks isn't reproducible. It very oft can exist and is so. Ultrasonic cleaning is reliable very ofttimes.

Merely specific results (claims by unmarried vendors of superior performance in unique applications) tin often exist difficult to reproduce in ultrasonic systems provided by other vendors.

In other words, if a supplier tin support a claim with repeatable performance data with your parts, a director should give great priority to that supplier in the selection procedure. ¹⁰⁵ This recommendation is consistent with the recommended approach for vendor pick in Affiliate 6, Section vi.8.

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Carbon

In Handbook of Stable Isotope Analytical Techniques, 2009

four-5.2.4 Pre-treatment of carbonate samples

4-5.2.4.1 Removal of organic compounds from carbonate samples

Carbonate minerals and fossil or soil samples containing organic compounds are treated past many of the analysts before digestion with phosphoric acid. There are several ways to remove organic compounds, which are reviewed beneath.

Emiliani (1966) stated that different methods used to remove organic thing from carbonate samples, while all having excellent reproducibility, may lead to somewhat different isotopic results, depending on the method used. Therefore, it is important to use the same technique for sets of samples to be compared, or else that appropriate corrections should exist made (Emiliani, 1966).

Interference during the MS measurement with contaminating gases: NCGs such as air (dissolved in the acid), CO and calorie-free hydrocarbons must exist avoided. For instance, a small amount of C_threeH_viii (commonly mass 44 to 46), trapped together with CO₂, tin can crusade errors in the isotopic value (Emiliani, 1966).

An first-class review on pre-treatment furnishings of h2o, H₂O₂ (xxx% solution) and household bleach (five.25% NaClO_iii and 0.15% NaOH solution) on the δ ¹³C and δ ¹⁸O values of coral skeletal carbonate was recently published by Grottoli et al. (2005). In Tabular array 4-5.1, a listing of treatment methods and literature where these treatments were reported is given (Grottoli et al., 2005; their Table one).

Table 4-5.ane. Listing of pre-treatment methods on coral skeletons carbonate and literature reporting the pre-treatment methods (slightly modified after Grottoli et al., 2005)

Pre-treatment	References
None handling reported and/or briefly washed or sonicated in water	Emiliani et al. (1978), Fairbanks & Contrivance (1979), Pätzold (1984), Cole & Fairbanks (1990), Leder et al. (1991), Pätzold et al. (1991), Winters et al. (1991) Emiliani et al. (1978) Fairbanks & Dodge (1979) Pätzold (1984) Cole & Fairbanks (1990) Leder et al. (1991) Pätzold et al. (1991) Winters et al. (1991) , Klein et al. (1992, 1993, 1997) Klein et al. (1992) Klein et al. (1993) Klein et al. (1997) , Cole et al. (1993, 2000) Cole et al. (1993) Cole et al. (2000) , Gagan et al. (1994, 1996) Gagan et al. (1994) Gagan et al. (1996) , McCulloch et al. (1994), Gagan & Chivas (1995) McCulloch et al. (1994) Gagan & Chivas (1995) , Swart et al. (1996a, b, c, 1998, 1999) Swart et al. (1996a) Swart et al. (1996b) Swart et al. (1996c) Swart et al. 1998 Swart et al. 1999 , Wellington et al. (1996), Cohen & Hart (1997) Wellington et al. (1996) Cohen & Hart (1997) , Felis et al. (1998, 2000, 2003) Felis et al. (1998) Felis et al. (2000) Felis et al. (2003) , Guzman & Tudhope (1998), Hemming et al. (1998) Guzman & Tudhope (1998) Hemming et al. (1998) , Grottoli (1999, 2002) Grottoli (1999) Grottoli (2002) , Grottoli & Wellington (1999), Guilderson & Schrag (1999), Hughen et al. (1999) Grottoli & Wellington (1999) Guilderson & Schrag (1999) Hughen et al. (1999) , Kuhnert et al. (1999, 2002) Kuhnert et al. (1999) Kuhnert et al. (2002) , Linsley et al. (1999, 2000) Linsley et al. (1999) Linsley et al. (2000) , Suzuki et al. (2001, 2003) Suzuki et al. (2001) Suzuki et al. (2003) , Cardinal et al. (2001), Cobb et al. (2001, 2003a, b) Cardinal et al. (2001) Cobb et al. (2001) Cobb et al. 2003a Cobb et al. 2003b , Kefu et al. (2002), Morimoto et al. (2002) Kefu et al. (2002) Morimoto et al. (2002) , Watanabe et al. (2002, 2003) Watanabe et al. (2002) Watanabe et al. (2003) , Maier et al. (2003)
Bleach (NaOH or NaClOthree) 5% for 1–24   h	Land et al. (1975, 1977) Land et al. (1975) Land et al. (1977) , Carriquiry et al. (1988, 1994) Carriquiry et al. (1988) Carriquiry et al. (1994) , Tudhope et al. (1995, 1996, 1997) Tudhope et al. (1995) Tudhope et al. (1996) Tudhope et al. (1997) , Allison et al. (1996), Leder et al. (1996), Guzman & Tudhope (1998) Allison et al. (1996) Leder et al. (1996) Guzman & Tudhope (1998)
Hydrogen peroxide (HtwoO2) v–35% for 1–36   h	Weil et al. (1981), Carriquiry (1994), Allison et al. (1996), Heiss (1996), Bessat et al. (1997), Boiseau & Juillet-Leclerc (1997) Weil et al. (1981) Carriquiry (1994) Allison et al. (1996) Heiss (1996) Bessat et al. (1997) Boiseau & Juillet-Leclerc (1997) , Boiseau et al. (1998, 1999) Boiseau et al. (1998) Boiseau et al. (1999) , Reynaud-Vaganay et al. (1999, 2001) Reynaud-Vaganay et al. (1999) Reynaud-Vaganay et al. (2001) , Heikoop et al. (2000), Reynaud et al. (2002) Heikoop et al. (2000) Reynaud et al. (2002)
Roasting at 200°C, 375°C or 475°C for 30–60 min or oxygen plasma roasting at 400°C for 20 min.	Epstein et al. (1953), Goreau (1977), Nozaki et al. (1978) Epstein et al. (1953) Goreau (1977) Nozaki et al. (1978) , Druffel (1985, 1997) Druffel (1985) Druffel (1997) , Porter et al. (1989), Aharon (1991) Porter et al. (1989) Aharon (1991) , Chakraborty & Ramesh (1993, 1997, 1998) Chakraborty & Ramesh (1993) Chakraborty & Ramesh (1997) Chakraborty & Ramesh (1998) , Druffel & Griffin (1993, 1995, 1999) Druffel & Griffin (1993) Druffel & Griffin (1995) Druffel & Griffin (1999) , Quinn et al. (1993, 1996a, b, 1998) Quinn et al. (1993) Quinn et al. (1996a) Quinn et al. (1996b) Quinn et al. (1998) , Dunbar et al. (1994), Linsley et al. (1994), Wellington & Dunbar (1995), Druffel et al. (2001) Dunbar et al. (1994) Linsley et al. (1994) Wellington & Dunbar (1995) Druffel et al. (2001)
Bleach and/or HtwoOtwo and roasting	Weber & Woodhead (1972), Weber et al. (1976), Dunbar & Wellington (1981), McConnaughey (1989), Dunbar et al. (1990) Weber & Woodhead (1972) Weber et al. (1976) Dunbar & Wellington (1981) McConnaughey (1989) Dunbar et al. (1990)

Roasting – The sample may be roasted under a flow of inert gas, east.g. dry nitrogen, helium, argon gas, to prevent oxidation (fractionation) of the carbonate minerals at a temperature between 375°C and 500°C for a flow of 15–60 min ( Craig, 1953; Epstein et al., 1953, 1961; Keith & Weber, 1964; Bowen, 1966; Emiliani, 1966; Marowsky, 1969b; Shackleton & Kennett, 1975; Duplessy, 1978; Gaffey et al., 1991; Quade et al., 1995; Quade & Cerling, 1995; Robert & Kennett, 1997 Craig, 1953 Epstein et al., 1953 Epstein et al., 1961 Keith & Weber, 1964 Bowen, 1966 Emiliani, 1966 Marowsky, 1969b Shackleton & Kennett, 1975 Duplessy, 1978 Gaffey et al., 1991 Quade et al., 1995 Quade et al., 1995 Quade & Cerling, 1995 Robert & Kennett, 1997 Figure 4-five.18). Aragonite volition be inverse into calcite by this process, important for the choice of the acid digestion fractionation factor ( Epstein et al., 1961; Gaffey et al., 1991) Epstein et al., 1961 Gaffey et al., 1991 . Lécuyer (1996) and Gaffey et al. (1991) Lécuyer (1996) Gaffey et al. (1991) reported the furnishings of heating on the structure of calcite and aragonite. CO_two was produced in minor quantities at more elevated temperature – the CO₂ volume increased with temperature. Dearest & Woronow (1991) discussed (chemic) changes in aragonite with a number of treatments to remove organic matter.

Effigy iv-5.18. Carbonate roasting line. A He-catamenia creates an inert atmosphere and carries away the gas produced by the roasting (after Bowen, 1966).

Roasting of aragonite is reported to cause O isotope fractionation (150–320°C: D. Mucciarone, Isogeochem list give-and-take – offset of −0.45‰; Grossman & Ku, 1986).

Samples are loaded into the roasting device while <200°C, and temperature is raised first after air is flushed out of the organization (twenty min flushing).

Helium gas, eventually used as inert gas, is cleaned by passing it over hot (750°C) copper oxide then through a liquid nitrogen trap (Epstein et al., 1961), or over hot copper (500°C) and through an activated charcoal trap cooled by liquid nitrogen (He flow charge per unit: 0.four   cm³/southward   =   lowest flow rate allowed to avoid exchange of oxygen from roasting with carbonate oxygen: Epstein et al., 1953; Emiliani, 1966) Epstein et al., 1953 Emiliani, 1966 .

Roasting of otholiths (accretionary aragonite structures located within the inner ear of fish) nether flow of He and at different temperatures was tested by Guiguer et al. (2003). Decision was that roasting, at temperatures between 200°C and 350°C, has no statistical meaning effect on both δ ¹⁸O and δ ¹³C values. ¹⁰

Roasting under vacuum (at 250–300°C: McConnaughey, 1989; at 475°C: Emiliani, 1966; Grottoli et al., 2005 Emiliani, 1966 Grottoli et al., 2005 : come across likewise Tabular array 4-5.1) is another possibility for removal of organic matter from carbonate samples (e.g. Naydin et al., in Russian, in Geochemistry 1956; Duplessy, 1978; Matthews et al., 1980; Lini et al., 1992; Sarkar et al., 1990; Zheng et al., 1993 Duplessy, 1978 Matthews et al., 1980 Lini et al., 1992 Sarkar et al., 1990 Zheng et al., 1993 ; S. Carpenter, Isogeochem listing word). Slight effect on the isotopic ratio and decrease in reproducibility were reported by McConnaughey (1989).

Winter and Knauth (1992) reasoned that Precambrian organic fabric generally is mature kerogen, which no longer contains volatile components which might interfere with the phosphoric reaction with the carbonate and fractionate the resulting isotopic value. Roasting of sample may be omitted in those cases.

Heating affects skeletons of different species in different ways. Dolomite tin can be formed from loftier Mg-calcites (Gaffey et al., 1991).

Organic material breaks down speedily when heated to temperatures ≥100°C. Thermal degradation of organic textile involves depolymerization, bail scission, loss of functional groups, formation of free radicals and evolution of H₂O, CO and CO₂ (Gaffey et al., 1991). Alteration of the organic compounds may go out behind a residue which coats the mineral phases and reduces their interaction in reactions (Gaffey et al., 1991). Roasting alters rather than removes organic matter from the carbonates (Gaffey et al., 1991). Grottoli et al. (2005), based on previous studies (Table four-5.1), stated that vacuum roasting results in an unpredictable and uncorrectable isotopic shift in coral skeletal δ ¹⁸O values, and concluded that this pre-treatment should no longer be good.

During heating of the carbonate, interstitial and inclusion fluids are likewise released from the carbonate (Gaffey et al., 1991) and may cause oxygen isotopic fractionation in the carbonate material.

Chemical treatment – Carbonate samples can be washed with a 5.0–v.25% sodium hypochlorite solution (= "Clorox") for one or 2 days at room temperature to remove possible organic matter [Emiliani, 1966; Clayton et al., 1968a; Coleman & Raiswell, 1981 (used a ane% solution); Love & Woronow, 1989; Grottoli et al., 2005 Love & Woronow, 1989 Grottoli et al., 2005 and Tabular array 4-5.1 ], followed by rinsing in distilled water several times (S. Carpenter, Isogeochem list discussion). Hypochlorite is used in combination with air abrasive methods and ultrasonic cleaning for removal of organic thing from samples past Yin et al. (1995).

Use of household bleach (mixture of NaClO and NaOH) was reported by Grottoli et al. (2005).

A combination of Clorox treatment and subsequent roasting nether He menses was reported as a ' convenient preparation technique for modern carbonates, peculiarly those rich in organic matter' (Emiliani, 1966).

Brasier et al. (1993) and McConnaughey (1989) Brasier et al. (1993) McConnaughey (1989) reported cleaning of carbonate fossils, containing organic thing, by washing with H_iiO_two and (CH₃)₂CO (acetone), followed by drying for 30 min at 60°C. H₂O₂ (10%) was used by D'Hondt & Lindinger (1994) to treat foraminifera or powders of organic material containing carbonate before reaction with phosphoric acid, while Honey & Woronow (1989) used a thirty% solution during 24   h to remove organic cloth from aragonite. H_twoO₂ handling was also reported by Boiseau & Julliet-Leclerc (1997) and Grottoli et al. (2005; come across also Table iv-5.1)

Love & Woronow (1989) used v   N NaOH solution to boil a sample for 3 min in gild to remove organic fabric.

Bleaching effects for removal of organic fabric were studied by Gaffey et al. (1991) and Gaffey & Bronnimann (1993) Gaffey et al. (1991) Gaffey & Bronnimann (1993) . They studied effects by H₂O₂, NaOCl (= Clorox) and NaOH reaction on organic and carbonate materials. Their findings were that full-strength (five%) NaOCl was most effective for organic matter removal, while H_iiO₂ can cause dissolution and etching of the carbonate cloth and NaOH alone inappreciably removed organic matter. Complete removal of organic material was only possible with complete dissolution of the carbonate fabric ( Gaffey et al., 1991; Gaffey & Bronnimann, 1993) Gaffey et al., 1991 Gaffey & Bronnimann, 1993 .

Sarkar et al. (1990) applied H₂O₂ and methanol handling to remove organic matter from carbonate and foraminifera material – encounter annotate below on the efficiency of this treatment.

D'Hondt & Lindinger (1994) soaked bulk sediment samples in a solution of 40   k hexametaphosphate and 20   L distilled deionized water, buffered to a pH of 7 by 58% ammonium hydroxide to sample foraminifera. Disaggregated samples were washed in h2o in 38 and 63   μm sieves and oven-dried (<50°C) overnight. This process was repeated two or 3 times to fully disaggregate and clean the foraminiferal samples.

Grossman et al. (1993) used an organic solvent to deliquesce organic material from the carbonate. After washing and air drying, samples (brachiopods) were immersed in the organic solvent for 24   h. After draining, the samples were soaked in tap water for some other 24   h and the coarse fraction (sieving: 850 and 125   μm mesh sieves) was air-dried at room temperature. Samples were selected, embedded in pre-evacuated epoxy and cut to study the carbonate (trounce) fabric under the microscope and by CL to select samples for isotopic analysis. A SS dental choice was used for collecting material to be analyzed.

Plasma ashing – Plasma ashers are used ( Goreau, 1977; Bernius et al., 1985; Franchi et al., 1986; Jones et al., 1987a; Goreau, 1977 Bernius et al., 1985 Franchi et al., 1986 Jones et al., 1987a R. McEwan, Isogeochem list discussion; M. Coleman, Isogeochem list give-and-take; South. Carpenter, Isogeochem list discussion; J. Cali, Isogeochem list discussion) to transfer organic matter in carbonates (or other rock types) into carbon.

Goreau (1977) institute no isotopic substitution between carbonate and oxygen caused past depression temperature oxygen plasma treatment (i   h) of sample. Standard plasma ashing treatment took 15 min.

Jones et al. (1987a) used a plasma unit at 150°C for hydrocarbon-rich carbonates before isotopic analysis and Ball et al. (1996) at 100°C to remove organic contaminants from small samples.

M. Coleman (ID) reported the written report by a PhD student showing that plasma ashers lead to practiced results while bleaching or H₂O₂ methods practise not. This effect was opposed by Due south. Carpenter (ID), who stated that, based on Gaffey & Bronnimann (1993), diluted hypochloric acid was the best method for removal of organic matter from carbonate stone.

J. Cali (ID) mentioned the need for utilise of dry samples (dried at low temperature in an oven) before organic matter can be converted into carbon in a plasma asher. The plasma asher needs a pressure level of <0.ane–one   mm Hg, and water-containing samples prevent reaching this pressure when pumped.

Franchi et al. (1986) pre-treated rocks by sonication in methanol earlier using a plasma asher.

4-5.2.4.two Diverse other purification methods

Foraminifera-containing samples can be crushed, washed in distilled water and treated in an agitator for 15 min. The samples are stale at 90°C. Shackleton & Opdyke (1973), Duplessy (1978) Shackleton & Opdyke (1973) Duplessy (1978) and Robert & Kennett (1997; in reagent-grade methanol) washed foraminifera in an ultrasonic bath for a few seconds and rinsed the samples 3 times in methanol.

Ultrasonic treatment was practical to make clean carbonate samples to remove clay from the surface, followed past drying and grinding (Zheng et al., 1993). Shackleton & Kennett (1975) applied ultrasonic cleaning in AnalaR grade methanol. Zhu & Macdougall (1998) practical ultrasonic cleaning in ultra-pure water (for Ca isotope determination) of foraminifera and carbonate ooze samples; a pocket-size amount (the finest fraction) of carbonate fabric was lost in this procedure.

iv-five.2.4.three General comments on pre-treatment of carbonates

Sarkar et al. (1990) tested different combinations of pre-handling of carbonates containing organic matter, including powdering (homogenization; larger reaction surface), treatment with H₂O₂ and methanol, vacuum roasting (400°C, 1–2   h) and ultrasonic handling (removal of inapplicable carbonate or other particles). Phosphoric acid digestion on these treated samples was compared with acid digestion on not-treated samples – no difference was plant in isotopic compositions of carbon or oxygen betwixt samples treated with unlike combination of treatments and untreated samples. Pure phosphoric acid was used instead of the 'green acid' containing CrO_iii as in the original prescription by McCrea (1950). This oxidation agent (CrO₃) causes addition of organic carbon to the CO_two during the 'green acid' assail, while pure phosphoric acrid shows no isotopic shift – no reaction between the acid and the organic matter occurs ( Duplessy, 1978; Sarkar et al., 1990) Duplessy, 1978 Sarkar et al., 1990 .

Complete removal of organic matter from carbonates (or sediments) is very difficult to establish without affecting the isotopic limerick of the material (Sheppard, personal communication). This is strongly dependent on the distribution and structure of the organic matter in the carbonate (sediment). If strongly 'intergrown' with the mineral or grain structures, and then complete dissolution of the material seems the simply fashion to attain complete removal of the organic matter, evidently rendering the fabric invalid for isotopic determination.

Grottoli et al. (2005) reasoned that the organic fraction (in corals) forms more often than not a very small fraction of the total carbon present, while merely some of the organic thing will react with the phosphoric acrid (producing CO₂) and therefore only can crusade very minor contamination of the carbonate carbon isotopic value. It was institute that pre-treated samples (coral skeletal fabric) shows greater variation in isotopic values than non-treated samples (eastward.g. Boiseau & Juillet-Leclerc, 1997; Grottoli et al., 2005) Boiseau & Juillet-Leclerc, 1997 Grottoli et al., 2005 .

Keatings et al. (2006) found that pre-treatment of ostracod valves, including roasting in a vacuum, plasma ashing and soaking in reagents such equally hydrogen peroxide, sodium hypochlorite, hydroxylamine hydrochloride solution and sodium dithionite complexing reagent, caused big chemic differences, and that all have the potential to change the isotopic composition of the ostracod valves. They recommend that valves but be cleaned manually, with fine brushes, needles and deionized h2o whenever possible. In cases where manual cleaning was insufficient to remove organic contamination, hydrogen peroxide and plasma ashing were expert methods for oxygen isotope assay, if no other analyses were to be performed. For carbon isotope analysis, only plasma ashing should be used.

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Microplastic Contamination in Freshwater Systems: Methodological Challenges, Occurrence and Sources

Rachid Dris , ... Bruno Tassin , in Microplastic Contamination in Aquatic Environments, 2022

iii.ii.iii.3 Sample Purification

The purification of microplastic samples facilitates the analysis and is a mandatory step prior to a spectroscopic characterization (FTIR/Raman microspectroscopy and pyrolysis-gas chromatography combined with mass spectrometry (GC/MS)). For a proper spectroscopic identification, biofilms and other organic and inorganic adherents take to exist removed from the microplastics, and the sample matrix has to be reduced to a minimum to minimize the nonplastic filter residue when filters accept to exist generated for spectroscopic measurements. Ultrasonic cleaning ( Cooper and Corcoran, 2022) for larger microplastics should exist considered with caution, as this technique bears a considerable risk to artificial generation of secondary microplastics from aged and brittle plastic material. A gentle way to clean larger plastic particles is stirring and rinsing with filtered freshwater (McDermid and McMullen, 2004) or ethanol (~   30%). Organic fabric in microplastic samples is usually reduced by strong acidic (Imhof et al., 2022; Claessens et al., 2022; Cole et al., 2022) or alkaline solutions (Cole et al., 2022; Dehaut et al., 2022), oxidation agents like hydrogen peroxide (Nuelle et al., 2022; Collard et al., 2022), or a combination of these agents (Dehaut et al., 2022). All these purification approaches are, nevertheless, limited, considering sensitive synthetic polymers can be lost during the treatment equally a cause of their chemical susceptibility (Claessens et al., 2022; Cole et al., 2022; Dehaut et al., 2022).

An culling plastic-friendly approach is the purification of ecology samples with enzymes (Cole et al., 2022; Catarino et al., 2022). This has been commencement suggested by Cole et al. (2014) who used proteinase-G to isolate microplastics from seawater samples with a high content of planktonic organisms. A significant drawback of the approach is the high cost for the enzyme. Meanwhile, the purification of plastic particles from mussel tissue with cheap enzymes has been reported (Catarino et al., 2022), and a universal enzymatic digestion protocol involving the sequential application of unlike technical enzymes and oxidation agents was recently adult (Löder et al., 2022).

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Vacuum and Tritium System

Georgij L. Saksagansky , Boris N. Kolbasov , in Fundamentals of Magnetic Thermonuclear Reactor Pattern, 2022

six.6.3 Vacuum Pumping Duct Blueprint

Let us consider the applied aspects of the 'pattern/materials/processes' triad implementation. The vacuum pumping duct design relies on a careful elaboration of the key elements, particularly the vacuum vessel and in-vessel components. Information technology is built on a number of pattern principles, the about important being the following:

•

focusing on the highest possible reliability of operation nether cyclic heat and mechanical loads as a key criterion controlling the technical determination-making process;

•

providing for structural sophistication of design elements – where this is instrumental in achieving reproductivity and removing subjectivity from the fabrication process;

•

unconditional compliance with the vacuum hygiene requirements;

•

attention to proper treatment of equipment employed for cleaning surfaces, surface microrelief optimisation and reduction of desorption flows, which may include procedures involving ultrasonic cleaning, electrochemical and electrophysical technologies to assistance in those processes;

•

intermediate degreasing and washing in the course of installation and adjustment of key units;

•

high-temperature conditioning and degassing of parts in vacuum furnaces using oil-costless pumping systems;

•

intermediate and finishing vacuum testing of parts and assemblies using mass spectrometry methods;

•

thermal cycling and resource testing, including intermediate tightness control, of parts exposed to high and cryogenic temperatures;

•

rut conditioning of ultra-high vacuum equipment parts combined with oil-free pumping (Tabular array vi.4). For sizable chambers, allowable heating temperature is adamant through joint thermal/concrete and durability modelling [4, fourteen].

Table 6.4. Typical Thermal-Vacuum Conditioning Modes

Limit of balance pressure level (Pa)	Heating modes
	Temperature (oC)	Duration (h)
10−5 to x−6	120–150	2–5
10−half-dozen to x−7	150– 300	10–50
10−8 and lower	∼400	50–150

The design principles and serviceability criteria for sectionalised all-metal assemblies are as follows:

•

Connections with as high an elastic energy equally practically possible have the highest serviceability. The resultant of the elastic forces in a sealing zone should take the same direction as the typical direction of contact pieces' thermal deformation.

•

A general physical serviceability criterion for a specific connectedness is the elasticoplastic deforming free energy needed to seal upwards the connection.

•

Profiled connectors meet the size and metal consumption minimisation criteria.

•

Connectors that tin can accumulate the energy of elastic deformation are suitable for exposure to thermal cyclicity. Therefore, fasteners of highly rubberband materials, spring washers, elastic compensators, two-bearing flanges, so on, are called for.

•

Connector configuration and material should be called such that mutual deformation of connecting parts exposed to thermal cyclicity is equally pocket-sized as possible.

•

Equipment for heating a structure that uses detachable connections should generate a uniform temperature field in the contact zone.

•

To achieve a tight seal forth the whole sealing contour, the spacing between fastenings and flange rigidity should be equally pocket-sized as possible. A long-lived connector should be sized such that the creep and relaxation of stresses are factored in.

•

Whatever mechanical contacts betwixt a shell and a flange should be avoided in the sealing zone. This is achieved through the use of slip-on flanges, clamps, and and so on.

•

Connector surface conditioning processes should be chosen such that no marks (scratches) normal to the sealing profile announced.

•

When using plastic sealant (indium, lead, etc.), it is desirable to utilise separation pad radial deformation limiters or see to it that the pads are particularly rigid in the seal airplane.

•

Contact pieces' profiles are non really critical to correctly designed connections that are upward to 40–50 mm across. For sizable connections, symmetric profiles may be suitable. Copper-indium bimetallic pads may be effective for reducing contact resistance. A 10–xv μm indium coating is applied to a pad made of copper wire or copper plate. The coated pad is heated at temperatures up to 200°C to accomplish a contact resistance that allows a hermetic sealing of the connection and the elastomeric sealant.

•

To create an of import assembled structure that is expected to exist rarely dismantled, information technology is reasonable to use semiremovable welded antenna connectors.

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Nutrient Safety Management

V. Kakurinov , in Encyclopedia of Food Safety, 2022

Application of Cleaning and Disinfection Agents

Cleaning and disinfection tin be performed with various methods. Usually, uncomplicated transmission cleaning performed with unproblematic tools is sufficient, but having in mind that in that location are more than few surfaces to be cleaned and disinfected, special equipment for providing mechanical energy and chemicals' dispersion is necessary. There are many methods and means of subjecting the surfaces to cleaning compounds and solutions. Depending on the economic system and effectiveness, in general, following methods are used:

1.

Manual method: This method is used for cleaning small items; chemic is applied and spread with brushes, sponges or cloths, scrubbers, etc. Positive aspects of this method are that a high degree of mechanical free energy can exist practical directly where it is needed, and if used with soak tanks (see below, Cleaning out of identify (COP) system), contact time tin be prolonged and chemical and temperature input tin can be increased. If larger areas are to be cleaned, only low levels of temperature and chemic energy tin can exist applied in order to go along the operator condom. Main advantages of this method are: low-cost equipment is required; information technology is adaptable to all types and sizes of facilities, equipment, and tools; and it is affordable in small nutrient-producing operations. Still, this method is labor intensive and time consuming; its effectiveness depends on human factor; most of the fourth dimension it is inconsistent; and there is greater opportunity for cantankerous-contagion.

2.

Soaking: Small equipment/fittings/valves are immersed in cleaning solutions in a small vessels or sinks, whereas larger vessels (tanks and vats) are partially filled with a cleaning solution. This solution should have high temperature (50–52   °C) and the equipment should be soaked for 20–30 min before being manually or mechanically scrubbed. One relatively recent approach is the ultrasonic cleaning tanks. In these tanks, equipment immersed in a cleaning solution is cleaned by the scrubbing action of microscopic bubbles produced past high frequency vibrations (xx  000–twoscore   000   cycles per s).

3.

Spray method: This is the almost used method in food industry. Using fixed or portable spraying units, cleaning solution is applied on equipment surfaces.

4.

CIP systems. This automated cleaning organization represents cleaning method where contact surfaces of vessels, equipment, and pipe work are cleaned in identify, i.due east., without dismantling. Primary energy source required for soil removal in this system is fluid turbulence in pipelines.

v.

COP organization. Nearly constructive cleaning for pocket-sized parts (e.g., pump rotors, hoses, tubing, piping, filter housings, needles, diaphragm valves, fittings, gasket, mixers, blenders, filler components, tools, bowls, belts, etc.) is in recirculating parts washer (called COP). These sanitary tanks are utilized in combination with a recirculating pump and distribution headers, which provide agitation of cleaning solution. Sometimes parts of this washer are serving as recirculating unit of measurement for CIP cleaning.

6.

Foaming: This method uses concentrated alloy of surfactants, which are added to highly concentrated alkaline or acid cleaner solutions. When applied with foam generator, this cleaner will have form of stable foam. This foam is clinging at surfaces. That manner, contact time between liquid and soil is increased and rapid drying and liquid cleaner runoff is prevented.

7.

Gelling: In this method, concentrated gelling agent is dissolved in hot h2o, which results in viscous gel formation. Later, appropriate cleaning agent is dissolved in the hot gel. Resulting gelled acid/alkaline detergent is sprayed on surface which is to be cleaned. Gelatinous cleaner forms thin motion picture on the cleaned surface for 30   min or more and attacks present soil. At the terminate, soil and gel are rinsed with pressurized hot water.

8.

Fogging systems: This method is used to create and disperse a disinfectant aerosol which reduces the number of airborne microorganisms (2–3   log in 30–60   min) and to use disinfectant to difficult-to-reach surfaces, especially overhead surfaces. For surface disinfection, fogging volition be effective only if sufficient corporeality of chemical is deposited onto the surface. Application of this method represents potential health take chances (inhalation). To avoid this risk, at least 45–60   min are required for settling of disinfectant fog and reentering of operatives in product area.

9.

Loftier- and low-pressure h2o jets: This method tin be used for application of different cleaners, particularly foam cleaners and rinsing of cleaning chemicals. Principal advantages of this method is fast application of cleaners on walls, floors, and stationary equipment and assuasive piece of cake attain to difficult-to-clean areas. However, during application, there is a loss of water temperature. Too, low-pressure level systems generally require higher h2o volumes and loftier pressure may cause cross-contamination with resulting aerosol's overspray (Figure 3).

Effigy 3. Aerosols creation resulting from very high pressure.

10.

Abrasive cleaning: Abrasive-type powders and pastes are still available and used for removing difficult soil. Complete rinsing is necessary and care should be taken to avert scratching stainless steel surfaces. Scouring pads should not be used on food contact surfaces because small metallic pieces from the pads may serve as focal points for corrosion or may exist picked up in the food.

Sanitation equipment should be dedicated to tasks for which they are designed. They should optimize cleaning effectiveness and minimize risks from cantankerous-contamination between different food-producing areas. For case, brushes should accept proper stiffness and they should not be used simultaneously for floor scrubbing, awarding of cleaners' solution, and equipment cleaning.

Very important feature for sanitation equipment is their hygienic design. This equipment should exist constructed from nonporous, nonoffensive, smooth, and easily cleanable materials. Crevices, pits, and gaps are not allowed because they are niches where microorganisms are collected, multiplied and spreading around. Most desirable construction cloth is not just the stainless steel but too mild steel or other corrosion field of study materials can as well exist used, provided that they are suitably protected (painted, coated, etc.). Wood as a structure material should be avoided.

After their use, cleaning tools and equipment should exist thoroughly cleaned and, if appropriate, disinfected and dried.

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Capture of Carbon Dioxide by Modified Multiwalled Carbon Nanotubes

Chungsying Lu , ... Hsunling Bai , in Environanotechnology, 2022

ii Materials and Methods

two.1 Adsorbents

Commercially bachelor multiwalled CNTs with inner diameter less than x nm (L-blazon, Nanotech Port Co., Shenzhen, China) were selected every bit adsorbents in this written report. The length of CNTs was in the range v–15 μm and the amorphous carbon content in the CNTs was less than 5 wt%. These data were provided past the manufacturer.

Raw CNTs were thermally pretreated using an oven at 300 °C for 60 min. After thermal handling, the CNTs were dispersed into flasks containing various kinds of chemical agents, including N-[3-(trimethoxysilyl)propyl]ethylenediamine (EDA), polyethylenimine (PEI; Acros Organics, analytical reagent, NJ, USA), and APTS (Riedel-de Häen, analytical reagent, Seelze, Germany), to determine the optimum modification of CNTs for enhancing CO_ii capture. Literature screening indicates that these chemic agents have been used to modify carbon adsorbents [13], zeolites [14, 23], or silica adsorbents [12, 24, 25 ]. The mixture was and then shaken in an ultrasonic cleaning bath (model D400H, Delta Instruments Co., USA) for 20 min and was refluxed at 100 °C for twenty h to remove metal catalysts. After cooling to room temperature, the mixture was filtered through a 0.45-μm mylon fiber filter, and the solid was done with deionized water until the pH of the filtrate was 7. The filtered solid was so dried at lxx °C for 2 h.

2.ii Adsorption Experiment

The experimental setup for CO₂ capture by CNTs is shown in Fig. 4.one. The adsorption column was made of Pyrex tube of length 20 cm and internal bore i.5 cm. The adsorption column was filled with ane.0 chiliad of CNTs (packing top = three.v cm) and was placed inside a temperature control box (model CH-502, Chin Hsin, Taipei, Taiwan) to maintain a temperature at 25 °C with the exception of temperature effect written report, in which the temperature range 5–45 °C (in a 10 °C increment) was tested.

Figure 4.1. A diagram of the experimental setup.

Compressed air was passed through a silica-gel air dryer to remove moisture and oil and so was passed through a loftier-efficiency particulate air (HEPA) filter (Gelman Scientific discipline, Ann Arbor, MI, USA) to remove particulates. The clean air was then served as a diluting gas and was mixed with pure CO₂ gas that was obtained from a pure CO₂ cylinder (99.9% purity) before entering the assimilation column. The influent CO₂ concentration and the arrangement menstruation charge per unit were controlled using mass menses controllers (model 247C four-channel readout and model 1179A, MKS instruments Inc., MA, USA). The mixed air was then passed downwardly into the adsorption column. The influent and effluent air streams were flowed into a gas chromatograph (GC) equipped with a thermal conductivity detector (TCD) by an motorcar sampling system. The variations in the influent CO_ii concentration were below 0.2%, and the system flow rate was controlled at 0.08 lpm that is equal to an empty-bed retention time of 4.half dozen due south.

The relative humidity was kept at 0% with the exception of moisture event study, in which the relative humidity range 0–100% was tested. Moisture was introduced into the air stream by dispersing the diluting gas through a water bath before being mixed with pure CO_two gas.

ii.3 Adsorption Capacity

The amount of CO₂ adsorbed on CNTs (q, mg/one thousand) was calculated as

(one) $q=\frac{\mathrm{ane}}{m}{\displaystyle \underset{0}{\overset{t}{\int }}Q\times \left(C_{\text{in}}-C_{\text{eff}}\right)dt}$

where m is the mass of virgin adsorbents (g), t is the contact time (min), Q is the influent flow rate (lpm), and C _in and C _eff are the influent and effluent CO₂ concentrations (mg/l).

2.iv Analytical Methods

CO₂ concentration in the air stream was determined using a GC-TCD (model GC-2010, Shimadzu Instruments, Japan). A 30-grand fused silica capillary column with inner diameter 0.32 mm and motion-picture show thickness 5.0 μm (AB-PLOT GasPro, USA) was used for CO₂ analysis. The GC-TCD was operated at an injection temperature of 50 °C, a detector temperature of 100 °C, and an oven temperature of 55 °C.

The structural information of CNTs was evaluated by a Raman spectrometer (model Nanofinder xxx R., Tokyo Instruments Inc., Japan). The carbon content in CNTs was determined using a thermogravimetric analyzer (model TG209 F1 Iris, NETZSCH, Bavaria, Germany).

The physical properties of CNTs were determined by N_ii adsorption at 77 K using ASAP 2022 surface area and porosimetry analyzer (Micromeritics Inc., Norcross, GA, United states). N₂ adsorption isotherms were measured at a relative pressure range 0.0001–0.99. The adsorption data were then used to decide the surface area of CNTs using the Brunauer–Emmett–Teller (BET) equation, whereas the pore size distributions (PSDs) of CNTs were adamant from the N₂ adsorption data using the Barrett–Johner–Halenda (BJH) equation.

The chemic properties of CNTs were determined using a Fourier transform infrared spectroscopy equipped with an attenuated total reflectance (FTIR/ATR; model FTIR-SP-1 Spectrum One, Perkin Elmer, Nippon).

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Limitations for Microplastic Quantification in the Ocean and Recommendations for Comeback and Standardization

Shiye Zhao , ... Daoji Li , in Microplastic Contamination in Aquatic Environments, 2022

2.3.2 Purification Digestion

Before the physical and chemical characterization of MPs, a step to eliminate matrix interferences and purify plastic particles needs to be conducted. These impurities can exist inorganic chemicals adsorbed onto the plastics or organic materials, such as hydrophobic adherents, biogenic residues in the form of tissue detritus or secretion from biotic samples, and microbial communities colonized on the surface of plastics (Löder and Gerdts, 2022; Zhao et al., 2022). Interfering materials can embrace the plastics and impede the identification of MPs. Both mechanical and chemic removal methods take been employed in earlier investigations. Mechanical methods, for example, ultrasonic bath, were used to remove extraneous material excess, such as loose debris, sand, calcium carbonate, NaCl, and other residues (Löder and Gerdts, 2022; Zhao et al., 2022 ). Treatment with ultrasonic cleaning, which might artificially introduce secondary MPs into samples by breaking weathered plastics and pb to overestimation of MP loads ( Löder and Gerdts, 2022), must be considered with circumspection. A range of digestion agents have been proposed for the removal of chemical materials in various environmental samples, including oxidizing agents such equally hydrogen peroxide (H₂O₂) (Löder and Gerdts, 2022); alkali agents such as potassium hydroxide (KOH) (Foekema et al., 2022; Lusher et al., 2022b) and sodium hydroxide (NaOH) (Nuelle et al., 2022; Cole et al., 2022; Dehaut et al., 2022); acids such every bit nitric acid (HNO_three) (Claessens et al., 2022; Wright et al., 2022; Devriese et al., 2022; Davidson and Dudas, 2022), muriatic acid (HCl) (Cole et al., 2022; Zhao et al., 2022), perchloric acid (HClO_iv) (Zoeter Vanpoucke, 2022), and formic acid (Hall et al., 2022); sodium hypochlorite (NaClO) (Collard et al., 2022; Enders et al., 2022); a mixture of H₂O_two and sulfuric acid (Klein et al., 2022); a mixture of HNO₃ and HClO₄ (De et al., 2022; Devriese et al., 2022); a mixture of peroxodisulfate potassium (Thou_twoS₂O_viii) and NaOH (Dehaut et al., 2022); sodium hypochlorite and HNO_three (Collard et al., 2022); KOH and NaClO (Enders et al., 2022); and enzymes (Cole et al., 2022; Löder and Gerdts, 2022; Catarino et al., 2022). However, some of these techniques can alter the concrete backdrop (color, shape and size, etc.) of samples or destroy pH-sensitive polymers present in samples. This results in inaccurate qualification and quantification of MPs. Color loss and softening were observed for acrylonitrile butadiene styrene, polymethyl methacrylate, PVC, polycarbonate (PC), expanded and solid polystyrene (EPS, PS), and PET after submersion in a mixture of acids recommended by the International Quango for the Exploration of the Sea (ICES) (Cole et al., 2022; Löder and Gerdts, 2022; Catarino et al., 2022). A solution of 40% NaOH resulted in the deformation of polyamide (PA), yellowing of PVC granules, and fusing of polyethylene (PE) particles (Cole et al., 2022). Nuelle et al. (2014) tested a solution of 35% hydrogen peroxide for 7 days on several polymer types and observed discoloration and credible size losses. Modification of morphological characteristics (size, color, and shape) could consequence in misidentification during visual or microscopic identification of MPs, which would limit the comparability beyond studies. Despite the possible changes in polymer morphology, polymeric limerick of these particles is yet identifiable using spectroscopy. However, the loss of materials and merging of plastics by chemic digestion may lead to underestimation of MP quantification. A solution of 35% HNO₃ melded some PET, loftier-density PE (HDPE), and polystyrene (PS) particles and dissolved all PA 6/vi fibers (Avio et al., 2022; Catarino et al., 2022; Dehaut et al., 2022). The complete dissolution of PA, PU, and a tire rubber elastomer in the acrid mixture (HNO₃ and HClO₄) were observed as well (Enders et al., 2022). Although some chemical digestion approaches did not impact plastic size, shape, and chemical constituents (Avio et al., 2022; Enders et al., 2022; Nuelle et al., 2022; Zhao et al., 2022), environmental plastics may exist subjected to more adverse furnishings, every bit they have poor structural integrity and resistance to chemicals in comparing with virgin plastics used in some tests (Enders et al., 2022; Lusher et al., 2022). These caustic digestive reagents in natural samples should be used with circumspection. Various enzymatic digestion techniques have been suggested to remove biological materials in field samples. Cole et al. (2014) first developed a sequential enzymatic digestion protocol to extract MPs in biota-rich seawater samples and marine zooplankton. Enzymes take been successfully used to purify other MPs from river h2o samples (Nuelle et al., 2022), mussel tissues (Catarino et al., 2022), and the digestive tracts of turtles (Duncan et al., 2022). Those results imply that enzymatic purification ensures MP integrity, meaning at that place is no loss, degradation, or surface modification during digestion. Additionally, enzymatic purification is a more environmentally friendly technique and should be considered by the scientific customs for monitoring MP aggregating in natural samples.

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A disquisitional review of current technologies for the liberation of electrode materials from foils in the recycling process of spent lithium-ion batteries

Yaqun He , ... Liping Li , in Science of The Total Environs, 2022

5.1 Ultrasonic cleaning

Ultrasonic cleaning with NMP or other solutions is an effective method to make electrode materials liberated from foils considering ultrasound can help break the adhesive force between electrode particles and foils so every bit to accelerate the liberation process. Li et al. proposed a procedure to achieve the liberation between electrode particles and foils based on the experiment results in their study. This procedure comprises three steps: (1) Spent LIBs were firstly crushed and sieved using a screen with 12 mm discontinuity; (2) The materials with size of −12 mm were put into an ultrasonic washing automobile for 15 min using mechanical agitation; (iii) The washed materials were obtained past filtration and stale, and and so electrode materials were obtained by sieving with a two mm aperture screen ( Li et al., 2009). He et al. also adopted ultrasonic cleaning methods to obtain electrode materials: (1) The discharging process of spent LIBs was conducted using v wt% NaCl solution. The discharged LIBs were manually dismantled to remove both the plastic and metallic shells. After dismantling, the cathode and anode were separated and so dried at 60 °C for 24 h; (2) The cathodes were manually cutting into minor sheets (10 × 20 mm) using scissors. These minor sheets were immersed in solvent in a conical flask and the whole were then placed in an ultrasonic cleaner at cleaning temperature 70 °C, solid/liquid ratio of ane:10 g/mL, ultrasonic frequency of 40 kHz, ultrasonic power 240 W, and ultrasonic fourth dimension of 90 min (He et al., 2022). The cathode particles were separated from the aluminum foil after ultrasonic cleaning and then were filtered, screened, and dried orderly.

Ultrasound-assisted chemical dissolution is of better performance than that without ultrasound. The application of ultrasound will better the efficiency of removal of organic binders. The electrode scraps need to be cut into small sheets in lodge to improve the ultrasonic cleaning efficiency.

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