Pulsed treatment chambers

AUchafaji, S.R. and Earid, M. 2007. An investigation on pulsed electric fields technology using new treatment chamber design. Innovative Food Science and Emerging Technologies 8 205-212. 

Donsi, G., Ferrari, G., and Pataro, G. 2007. Inactivation kinetics of Saccharomyces cerevisiae by pulsed electric fields in a batch treatment chamber The effect of electric field unevenness and initial cell concentration. Journal of Food Engineering 78 HA-192. 

Manas, P., Barsotti, L., and Cheftel, J.C. 2001. Microbial inactivation by pulsed electric fields in a batch treatment chamber Effect of some electrical parameters and food constituents. Innovative Eood Science and Emerging Technologies 2 239-249. 

Qin, B., Zhang, Q., Barbosa-Canovas, G.V., Swanson, B.G., and Pedrow, P.D. 1995a. Pulsed electric field treatment chamber design for liquid food pasteurization using a finite element method. Transactions oftheASAE 38 557-565. 

At the age of 77 days, 10 nursery plants were destructively harvested and other 30 plants were transferred to 3 sunlit growth chambers (32/20 C day/night) for water stress treatments. These consisted of 12, 8, and 4 irrigation pulses per day for the C", M", and S chambers, respectively (60 ml pot in each pulse). The chambers have been described in detail elsewhere [3, 4, 5]. Each chamber formed a closed system, measuring 0.5 by 2.0 m and a height of 1.5 m, around the aerial parts of 10 plants. 

A typical PEF system consists of a pulse modulator which supplies high-voltage pulses of sufficient peak voltage and repetition rate, and a treatment chamber in which the product is exposed to the electric field. For pumpable media such as fruit juices, milk or fruit mashes, the treatment can be performed continuously in a tubular treatment chamber consisting of cylindrical electrodes. Whole fruits or pieces can be submerged in water in a flume, but a dry PEF treatment with direct contact between the product and the electrodes is desirable for meat pieces, in order to prevent crossFurther information on the principles and mechanisms of action of PEF, as well as its technical aspects and appUcations, are available elsewhere (Lelieveld et al, 2007 Raso and Heinz, 2007). 

The implementation of PEF treatments in existing industrial processing lines has been realized for numerous installations, based not only on adapted treatment chamber designs but also on the availability of industrial-scale pulse modulators. Although the integration of PEF treatments into complex processing... 

Huang K, Wang J. 2009. Designs of pulsed electric fields treatment chambers for liquid foods pasteurization process A review. J Food Eng 95 227-239. 

Yin Y, Zhang QH, Sastry SK. 1997. High voltage pulsed electric field treatment chambers for the preservation of liquid food products. United States Patent 5,690,978. 

Safety assessments in travoprost studies have included evaluation of visual acuity, pupil diameter, iris color, anterior chamber flare, conjunctival hyperemia, pulse, blood pressure, blood chemistry profiles, and urinalysis values. The observed adverse events have generally been mild to moderate and have resolved without treatment. Most of the side effects seen with latanoprost can occur with travoprost treatment. Conjunctival hyperemia induced by travoprost is clinically insignificant but generally more than that observed with latanoprost. 

Fleischman, G.J., Ravishankar, S., and Balasubramaniam, V.M. 2004. The inactivation of Listeria monocytogenes by pulsed electric field (PEF) treatment in static chamber. Food Microbiology 21 91-95. 

Figure 9-37. Permeability of the polymer membrane from acetate cellulose with respect to He, H2, CO2, and CH4 as function of microwave plasma treatment time o, Hhc , Hh a, ricoz +, ncH< microwave pulse power 2 kW pulsing period 2 ms pulse duration 100 /ts gas pressure in the microwave discharge chamber 2 Torr nitrogen/oxygen ratio in the plasma gas N2 02 =4 1 flow rate of the plasma gas 40 cm /s.

The analysis carried out by AES showed that the films formed by one pulse of plasma treatment possess the complex composition (Fig. 2a) N, C and W from vacuum chamber atmosphere, Fe and C from the shock compressed layer. Further increase of the pulse numbers leads to more homogeneous distribution of elements (Fig. 2b). This effect is associated with high temperature of the surface during the plasma treatment resulting melting and subsequent liquid phase... 

The authors of this chapter conducted a recent study, which evaluated the efficacy of plasma treatment on a model wood substrate. In order to imderstand the effect of plasma treatment on wood-based fibers, clear pine wood veneers with an identical chemical composition was used as a model substrate. Plasma treatment was conducted using a custom built 13.56MHz inductively coupled plasma chamber in continuous wave mode (CW) and continuous wave mode plus pulse plasma mode [60]. During continuous wave mode the plasma is always on , so the formation of functional groups is accompanied by their destruction due to the continuous ion bombardment or surface ablation. During the pulse mode, the plasma source is on for a specific period and the plasma generated is similar to the continuous wave mode, where the plasma reactive species interact with the surface of the wood substrate. During the period when the... 

W2N nanoparticles (below 10 nm) were prepared via a one-step pyloysis of polymeric mixture of WCI4 and urea glass like previous y-Mo2N synthesis (30). The surface area of W2N was 64 m /g after heat treatment with N2 gas at 1073 K. The W2N thin film with several micro-sized thicknesses on a Si wafer could be formed via the reactive pulsed laser deposition method (36). The thickness and phase was adjusted by N2 pressure and temperature of a vacuum chamber. 

Functionalisation of VACNT. Nanotube functionalisation and exfoliation were performed in a much less powerful pulsed DC plasma reactor. The chamber walls form the anode, while the CNT samples were placed over the substrate holder cathode. The reactor chamber was first evacuated to 10 Torr by a diffusion pump to ensure low residual air. Then pure mygen (1 seem) was introduced and the ehamber pressure was controlled at 80 mTorr. The pulsed DC power supply was set at —700 V at 20 kHz and 45% duty cycle. Treatments were aeeom-plished within 2 minutes. 

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