Ultrasonic compaction

In this study, it was seen that zein and composites of zein and DDGS can be ultrasonically compacted into a solid with tensile strength ranging from 10-12 MPa. In addition, the ideal material composition is 75% Zein and... 

POTENTIAL ULTRASONIC COMPACTION OF ZEIN AND DISTILLERS DRY GRAIN (DGG) 1061... 

After firing, the supports were machined to the required dimensions of 0 39 mm, 2 mm thickness and polished until a shiny surface was obtained. Before use the supports were cleaned in ethanol by ultrasonic treatment to remove any debris that remained in the pores after machining. After cleaning the supports were fired at 800°C to remove ethanol left in the pores. The typical thickness of a final flat membrane support was 2 mm. The sintered compacts had a porosity of 32%. 

Nebulizer jet nebulization ultrasonic nebulization. Generates small particles with higher delivery capacities than pMDIs and DPIs no coordination required. Inconvenient long inhalation times poor dose control lack of portability expensive. More compact and portable devices breath enhanced nebulizers dosimetric nebulizers. 

Although they are compact units and hence easily portable, the dense aerosol plume produced often has a population of drops with a higher MMAD and GSD in comparison to air-jet nebulizers and hence ultrasonic nebulizers tend to be less widely used. 

On the other hand, application of ultrasonic energy results in an increase in the temperature of the die during the compaction process. The consequences of this fact should be taken into account and cannot be neglected in the case of thermola-bile drugs and/or excipients [87,88]. 

It is therefore more cost effective to use a large ultrasonic system supplying 80 kW to process liquids at a flow-rate of 10 m /h than to use 5 ultrasonic processors with a power of 16 kW each or 40 processors with a power of 2 kW each. The robustness of the transducer enables its use under heavy-duty industrial conditions. Also, the processor can be designed to be explosion-proof. Like the transducer and the flow cell, the generator is housed in two connected compact stainless steel cabinets. This makes the device self-contained, robust and easy to install. The standard footprint of a 16-kW system is just 600 mm x 1200 mm. 

All comments above about common and specific variables for ultrasonic baths and probes also apply to continuous US-assisted digestion, which additionally involves dynamic variables. The most influential dynamic variable is the flow-rate of the liquid phase, which should be set in such a way as to avoid compaction of the solid in the chamber and ensure effective contact of the two phases. Consequently, the flow-rate of choice in each case will depend on the particular solid-liquid system. 

Membrane compaction and fouling-cleaning studies by ultrasonic time-domain refiectometry... 

Figure 10.6. (A) Experimental set-up used for membrane compaction studies of a high-pressure separation system by ultrasonic time-domain reflectometry (B) Scheme of the separation cell showing the externally mounted transducer and the primary reflections identified as a, b and c, which correspond to the top plate-feed solution interface, feed solution-top membrane surface interface and bottom membrane surface-support plate interface, respectively (C) Change of the arrival time which translates into changes in membrane thickness during compaction. (Reproduced with permission of Elsevier, Ref [63].)...

In-line measurements of particle size distributions are essential in order to maximize production capacity and product quality. Ultrasonic attenuation is emerging as a technique, with capabilities beyond those of light scattering. In addition to the needs of industry for compact, robust instrumentation, this method is capable of operating at high concentrations, thus eliminating the need for an expensive dilution step, which may alter the very properties one wishes to measure [225,226]. 

Inhomogeneous gold polycrystallites with compact structure and a broad range of orientations were formed after 45 min of ultrasonic treatment in a home-developed sonoreactor at the constant temperature. Sonication for additional 40 min recrystallized highly monodisperse platinum nanoparticles with smaller size. The fastest catalysis was enabled by platinum nanoparticles after sonication in the poly vinyl pyrrolidone solution for one hour, while the lowest activity was found for particles after the ultrasonic treatment for 20 min in the ethylene glycol solution. Amorphous and polycrystalline platinum nanoparticles before and after sonication in water have similar catalytic efficiencies. 

Fig. 6. Sensitivity of ultrasonic spectroscopy to coarse, compact particles (1.5 pm).

The size, geometry and void volume of the extraction cell, in addition to its amenability to decreasing compaction by stirring or ultrasonication, all influence the SFE process. 

Similar effects can be observed during electrodeposition in an ultrasonic held.33 Copper deposits obtained in an ultrasonic held were compact and more ordered structure than copper deposits obtained without an effect of ultrasonic helds. 

Incidentally, those wishing to follow up these studies should note that nowhere in refs. 167, 168, and 169 is given full experimental details of the preparative electrochemical set-up. Even the nature of the electrode material is not obviously stated, and the reader is invited to refer for details to an earlier paper [170] which concerns electrochemical but not sonochemical studies. While journal editors rightly strive for brevity and compactness in reports, a reader approaching this work from the ultrasonic viewpoint (i.e. unfamiliar with the history from the polymer side) will find the paucity of experimental detail in such seminal papers to be a significant omission. 

Powder mixtures were placed in a graphite mould and then sintered at the temperatures shown in Table 1 for 2 h by hot pressing at 30 MPa in an Ar atmosphere. The sintered compacts were ground to a thickness about 0.5 mm and then diamond-polished. They were finally cut into small round disks, 10 mm in diameter and about 0.5 mm in thickness, with a ultrasonic cutting machine. 

Two methods are used to measure and monitor entrained air in a stock system compression and ultrasonics. Many different types of mechanical compression apparatus have been used in the pulp and paper industry (Woodworth, 1990). The portable Entrained Gas Tester (EGT) is one device that is commonly used to profile stock systems by determining the level of entrained air in a stock at a particular sample point. The EGT operates on a mechanical compression technique based on Boyle s law of gases. The operation of the EGT is described in detail in the manufacturer s manual. Advantages of the portable EGT are that the test is quick to carry out and the test unit is compact and portable, allowing the user to conduct the test at-location. However, this test is very operator-sensitive and there can be high variability of data in addition to a time delay before results become available. 

TouchSpray can best be described as a vibrating-orifice ultrasonic nebulizer and was developed by the Technology Partnership (TTP), U.K. This technology has only recently been announced and little is as yet published (26). This new method for aerosol generation is compact (Fig. 11) and based on sound pressure, which forces fluids through small holes in a membrane. Unlike traditional... 

Designed to sort compacted bottles, the Poly-Sort system employs conveyors for singulation, and two devices for color and chemical composition identification. A vibratory conveyor singulates bottles a read conveyor transports bottles to an ultrasonic sensor that detects their position a near-infrared system detects the resin type a camera detects the color of the container a computer integrates data and makes an identification air jets divert bottles to the appropriate segregation conveyor or hopper. 

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