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The mechanism of Cu2+ loading into commercially available natural HEU-type and synthetic LTA-type zeolites for their possible use in environmental processes, such as water and air treatment applications, was studied. Elemental analysis, SEM/EDXS, XRD, XAS and XPS analyses revealed 4-fold coordination of Cu2+ cations with oxygen atoms in the pores, a predominant location of copper atoms on the surface of crystallites and retained crystallinity of zeolites throughout the processes. The post-treatment of Cu2+-loaded samples with HCl and/or NaCl solutions confirmed the predominantly reversible sorption of copper on zeolites from aqueous solutions by ion-exchange mechanism and, therefore, excellent regeneration possibilities for both types of zeolites. Furthermore, with the calcination of exhaust metal-loaded zeolites, catalysts for total toluene oxidation reaction, as a model VOC pollutant, were obtained.

In this work, the use of a coupled process, alkyl glycoside (APG) enhanced soil desorption followed by the zero-valent iron-ethylenediaminetetraacetic acid (EDTA)-air (ZEA) Fenton-like system, was investigated for the remediation of a simulated hexachlorobenzene (HCB)-contaminated diatomite soil and a real HCB-contaminated soil. Three surfactants with different concentrations were studied to obtain the suitable soil desorption agent. Compared with APG0810 and Triton x-100, APG0814 showed a better solubilization effect due to its lower critical micelle concentration. With addition of 3000 mg L-1 APG0814, 35% of HCB was removed from contaminated diatomite soil, and a small amount of residual APG in diatomite soil was found to be beneficial for the soil dispersion. After treatment with the ZEA system, the removal efficiency of HCB in the diatomite soil desorption solution reached 76% in 2 h; we observed that a small amount of APG retained in the desorption solution accelerated the HCB removal. A real HCB-contaminated soil was used to verify the remediation effects. This study demonstrates that our approach is a feasible alternative for remediating soil contaminated with hydrophobic organic compounds.

Background: Antagonistic yeast and hot air treatment are two promising methods for conferring resistance to pathogenic fungi. The study assessed the effectiveness of hot-air treatment (45 °C, 4 h) and antagonistic yeast (Pichia guilliermondii at 108 CFU mL-1 ) alone or in combination on the two major postharvest diseases (Rhizopus stolonifer and Penicillium expansum), as well as the quality and antioxidant parameters in harvested peaches.; Results: The combination of hot-air treatment and Pichia guilliermondii had notable inhibitory effects on infections in peach fruit wounds. In addition, the individual hot-air treatment or Pichia guilliermondii could improve quality indexes to varying degrees, but the combination of the above two treatments could achieve the highest efficacy. Furthermore, compared with other groups, the combined treatment induced the highest activities of superoxide dismutase and catalase, improved the content of total phenolics and reduced glutathione most obviously. Lastly, the most significant reductions in malondialdehyde content and relative electrical conductivity were observed in the combination-treated fruit.; Conclusions: The combined treatment could control fungal diseases, besides delay the decline of quality and antioxidant parameters, so as to achieve the purpose of fresh keeping for harvested peach fruit. © 2018 Society of Chemical Industry.; © 2018 Society of Chemical Industry.

Fruit softening facilitates pathogen infection and postharvest decay, leading to the reduction of shelf-life. Hot air (HA) treatment at 38 °C for 12 h is effective in reducing postharvest disease and chilling injury of tomato fruit. To explore the effect and mechanism of HA treatment on reducing postharvest decay and softening of cherry tomato, fruit at the mature green stage were treated with HA and then stored at 20 °C for 15 days. Changes in natural decay incidence, firmness, cell wall compositions, activities and gene expression of cell wall-degrading enzymes of cherry tomatoes were assessed.; Results: HA treatment reduced natural decay incidence, postponed the firmness decline, inhibited the respiration rate and ethylene production, and retarded pectin solubilisation and cellulose degradation of cherry tomatoes. Enzymatic activities and gene expression of pectin methylesterase, polygalacturonase, cellulase and β-galactosidase were inhibited by HA treatment. In addition, the gene expression of LeEXP1 was reduced, while LeEXT was up-regulated after HA treatment.; Conclusions: Our findings suggested that HA treatment could inhibit cell wall degradation and postpone softening of cherry tomatoes by regulating gene expression and activities of cell wall-degrading enzymes, resulting in the reduction of postharvest decay. © 2017 Society of Chemical Industry.; © 2017 Society of Chemical Industry.

Verticillium wilt, caused by the fungus Verticillium dahliae, is currently the most important disease affecting olive in the Mediterranean basin. There are no effective treatments for controlling this disease. The use of infected nursery stocks has largely contributed to the spread of the pathogen, and therefore the development of treatments to preventively sanitize the propagation stock is critical in the nursery industry. This study describes novel techniques to achieve this aim. The effects of several temperature–exposure time combinations were evaluated: (i) the survival of pathogen on culture medium (PDA); (ii) the pathogen viability on infected shoots and plants; (iii) the vegetative growth of plants of several cultivars; and (iv) the rooting ability of cuttings. The colonies of the pathogen growing in PDA were killed after 8 h and 60 min of exposure at 40 and 47°C, respectively. Temperatures ≥42°C for at least 2 h were lethal for the pathogen infecting the shoots. Likewise, moist hot air treatments at 42–44°C for 6–12 h eradicated the pathogen, without compromising the viability of the plants. Five olive cultivars were also evaluated and classified according to their thermotolerance as follows: sensitive (Chiquitita), moderately sensitive (Koroneiki, Frantoio and Picual) and heat tolerant (Arbequina). However, the optimized sanitation methods were applicable to all of the cultivars. Finally, heat treatments were applied to unrooted cuttings, which severely affected their rooting ability. Thus, this study developed a hot air treatment to produce V. dahliae-free olive nursery plants., This research was funded by the Spanish Ministry of Education and Science (project AGL2004-7495 that was co-financed by the European Union FEDER Funds) and by the Andalusian Regional Government (project P08-AGR-03635). J.M. holds a Talent Hub fellowship launched by the Andalusian Knowledge Agency, co-funded by the European Union's 7th FP, Marie Skłodowska-Curie actions (COFUND–Grant Agreement no. 291780) and the Junta de Andalucia. C.M.D. is the holder of a fellowship from the Agrifood Campus of International Excellence CeiA3.

Air-promoted adsorptive desulfurization (ADS) of commercial diesel fuel over a Ti-Ce mixed oxide adsorbent in a flow system is investigated in this work. The fresh/spent adsorbents were characterized using X-ray absorption near edge structure spectroscopy. Results show that sulfoxide species are formed during air-promoted ADS over Ti0.9Ce0.1O2 adsorbent. Adsorption selectivity of various compounds in fuel follows the order of dibenzothiophene sulfone > dibenzothiophene ≃ benzothiophene > 4-methyldibenzothiophene > 4,6-dimethyldibenzothiophene > phenanthrene > methylnaphthalene > fluorene > naphthalene. The high adsorption affinity of sulfoxide/sulfone is attributed to stronger Ti-OSR2 than Ti-SR2 interactions, resulting in significantly enhanced ADS capacity. Adsorption affinity was calculated using ab initio methods. For Ti-Ce mixed oxides, reduced surface sites lead to O-vacancy sites for O2 activation for oxidizing thiophenic species. Low temperature is preferred for air-promoted ADS, and the Ti-Ce adsorbent can be regenerated via oxidative air treatment. This study paves a new path of designing regenerable adsorbents. © 2014 American Institute of Chemical Engineers AIChE J, 61: 631–639, 2015

The negative impact of the presence of volatile organic compounds (VOCs) on indoor air quality has motivated researchers to develop different air treatment technologies. Although, building mechanical ventilation systems can provide a comfortable thermal indoor environment, they are not capable of removing the VOCs effectively. Thus, other components must be integrated with them to be able to carry out this function. Plasma-based air treatment techniques are a series of processes in which a high voltage discharge is used for elimination of VOCs. Development of plasma-based methods, and their capabilities for chemical gas decomposition, has motivated designers to employ these methods for indoor air purification. This paper addresses the outcomes of a critical literature review on plasma-based air cleaner technologies, thermal to non-thermal plasma and plasma catalyst, and their application for indoor environment VOCs removal. The reaction mechanism, effect of different parameters on the performance of the method, and abilities and limitations of these methods are discussed. Different types of reactors and the most common used catalysts are classified. The role of the presence of the catalyst in improving the non-thermal plasma efficiency is reviewed. Finally, the scope of the future work to enhance the performance of this method for application in sustainable buildings is discussed.

Summary The impact of heat treatment using hot air (HT 45 °C and 55 °C for 1 h) and two active modified atmosphere packaging (MAP) conditions of high oxygen atmosphere (HOA: 80 kPa O2, 20 kPa N2) and high CO2 atmosphere (HCA: 20 kPa CO2, 80 kPa N2), individually or combined, on the antioxidant capacity, polyphenols, vitamin C content, total anthocyanins, polyphenoloxydase (PPO) activity and shelf life of fresh-cut (FC) pomegranate arils stored for 14 days at 4 °C was studied. The results indicate that HT 45 °C along with HOA inhibited PPO activity and prevented loss of antioxidant capacity, vitamin C and phenolic compounds in arils, in comparison with control and HT 55 °C. All treatments reduced the accumulation of anthocyanins, but HCA-treated arils lost more anthocyanins besides having worse a* colour parameter values. No significant differences in titrable acidity (TA) and total soluble solids (TSS) were observed between treatments. The combination of HOA and HT 45 °C enhanced the benefits of applying each treatment separately and could be useful to improve and extend postharvest life of pomegranate FC arils.

BACKGROUND To understand whether arginine catabolism might be involved in hot air (HA)-induced chilling tolerance mechanism in tomato fruit, we investigated the effect of HA treatment on endogenous arginine catabolism in relation to chilling injury. RESULTS Tomato fruit were harvested at mature green stage and treated with HA at 38°C for 12 h and then stored at 2°C for 21 days. The effects of HA treatment on fruit chilling injury and gene expression levels or enzyme activity, and metabolites related to arginine catabolism were evaluated. HA treatment reduced the chilling injury symptoms of tomato fruit and enhanced the accumulation of endogenous polyamines, especially putrescine and proline. This accumulation is associated with the increased transcript levels of genes encoding arginase (LeARG1 and LeARG2), arginine decarboxylase (LeADC), ornithine decarboxylase (LeODC) and ornithine aminotransferase (LeOAT) at most sampling times. However, HA treatment had little effect on nitric oxide synthase activity and nitric oxide concentration. CONCLUSION These results revealed that the reduction in chilling injury by HA treatment may be due to the accumulation of putrescine and proline induced primarily by activating the catabolism of endogenous arginine. © 2013 Society of Chemical Industry

Background Livestock operations are under increasing pressure to fulfil minimum environmental requirements and avoid polluting the atmosphere. In regions with high farm animal densities, new farm buildings receive building permission only when biological exhaust air treatment systems (BEATS) are in place, such as biofilters. However, it is currently unknown whether BEATS can harbour pathogens such as zoonotic agents, which are potentially emitted via the purified gas. Because BEATS are located very close to the livestock building, it is assumed that BEATS-related microorganisms are aerially transported to farm animals via the inlet system of the ventilation system. To support this hypothesis, a computer simulation was applied to calculate the wind field around a facility consisting of a virtual livestock house and an adjacent biofilter. Results Under the chosen wind conditions (speed and direction), it can be shown that turbulences and eddies may occur in the near surrounding of a livestock building with an adjacent biofilter. Consequently, this might cause the entry of the released biofilter's purified gas into the barn, including possible microorganisms within this purified gas. Conclusions If field investigations verify the results of the simulations, counter-measures must be taken to ensure biosecurity on farms with BEATS. © 2013 Society of Chemical Industry

The emission of large amounts of solvent vapors with exhaust air from industrial production into the environment is a serious problem. In Germany, industry-sector-specific threshold values are applied and technical measures for pollution reduction are required. Different techniques for exhaust air cleaning are in use but still posing problems concerning costs and reliability. For these reasons, the development of processes for exhaust air treatment is the subject of the current research. A new concept for exhaust air cleaning is introduced that combines absorption of a solvent vapor by an organic fluid and a subsequent adsorption by a molecular sieve placed in the absorber. It was managed to close the loops of solvent recovery and sorbents regeneration. In laboratory-scale experiments it was possible to reduce an initial ethylacetate pollution of 800 mg/m3 or 349 mg C/m3 below the limit value of 75 mg C/m3 over 60 h duration. Thermogravimetric measurements assisted to define optimum conditions for solvent recovery at 180°C from the molecular sieve. One unexpected positive finding was the considerable increase in the solvent release in the presence of the absorption fluid while adsorption isotherms revealed first insight into this process.

Uniform core@shell cobalt nanoparticles (NPs) embedded into mesoporous silica (Co@m-SiO2) were prepared by a simple two-step procedure. Metallic cobalt NPs stabilized by sodium citrate and a nonionic polymer poly(vinylpyrrolidone) were coated by a homogeneous silica shell by using a modified Stober protocol. In the second step, the mesoporosity of the shell was produced through a pseudomorphic transformation by using cetyltrimethylammonium bromide in alkaline media. An in situ XRD study performed in air on the resulting Co@m-SiO2 solid revealed that this new material is stable under ambient conditions and even resistant towards oxidation up to 450 °C. It is noteworthy that only 30 % of the Co3O4 phase is detected after air treatment at 550 °C. As a result, the core@shell morphology is preserved even at 700 °C in air, which shows the stabilization effect and sintering resistance of this type of structure.

AIR:EAU:BIOVERT:RAFFINAGE+CDS:PGA:CGE:CGO; The scope of this concept article is to demonstrate through few selected examples taken from recent literature that heterogeneous catalysis is presently an essential tool to achieve a sustainable use of resources for energy, chemical, and material production and to preserve and rehabilitate our environment. Using heterogeneous catalysts for the production of fuels and chemicals reduce the energy demand and minimize the formation of non-recyclable wastes by increasing the activity and selectivity of fossil and renewable resource conversion. It is now the essential tool for the treatment of pollutants in air and water. The efficiency of photocatalytic processes for the treatment of toxic compounds in air and water is also highlighted. The destruction of pollutants by mineral dust in the atmosphere demonstrates the major role that heterogeneous catalytic processes plays for global environmental preservation.

BACKGROUND Biofilters are suitable to treat industrial emissions polluted with volatile organic compounds (VOCs), responsible for photochemical smog and depletion of the ozone layer. This study analyzes the performance of a biofilter with Macadamia ternifolia nutshells as a carrier material treating air streams contaminated with ethylbenzene under mesophilic conditions with continuous feeding. RESULTS The biofilter was operated continuously for 5 months applying several inlet loads (IL), empty bed residence times (EBRT) and temperatures. At a temperature of 303 ± 1 K removal efficiencies (RE) higher than 90% were obtained for ILs lower than 85.6 g m−3 h−1 and 70.6 g m−3 h−1 at an EBRT of 150 and 90 s. The yield coefficient resulted in 0.73 g of dry biomass formed per g of ethylbenzene degraded. Michaelis–Mentens half saturation parameter Km and maximum volumetric elimination rate rm were calculated for EBRT of 90 s, Km = 0.28 ± 0.09 g m−3 and rm = 89 ± 11 g m−3 h−1, and 150 s, Km = 0.72 ± 0.18 g m−3 and rm = 117 ± 15 g m−3 h−1. CONCLUSIONS The experimental data shows that a biofilter with Macadamia ternifolia nutshells (waste material in Thailand) as a carrier material is a good option for air treatment in tropical areas with typical temperatures varying from 292 to 313 K, using ethylbenzene as a test substrate. Copyright © 2012 Society of Chemical Industry

Apples (Malus domestica Borkh. cv. Gala) were heat-treated at 38C for 4 days (heat treatment [HT]) before or after coated with 1% chitosan (CTS). Following treatment, apples were stored at 0C for 8 weeks and 20C for 7 days as shelf life. The effectiveness of the combined treatments on the ripeness, quality and decay development caused by Penicillium expansum and Botrytis cinerea was evaluated. Severe heat damage was observed on the fruits heat-treated after CTS coating (CTS + HT), appeared as external decay and internal brown after treatment. However, no damage on fruits heated before CTS coating (HT + CTS) during the whole storage. Besides the completely control of blue mold and gray mold on artificially inoculated fruits during storage, the HT + CTS treated fruit showed the lowest respiration rate, ethylene evolution, malondialdehyde and membrane leakage, and the highest firmness and consumer acceptance among the treatments. At the same time, this combined treatment could inhibit the lost of green color, titratable acidity and weight loss compared with HT alone. PRACTICAL APPLICATIONS “Gala” apple fruits become more popular in the world because of its high productivity and good quality. Hot air treatment alone has been used to delay ripening of Gala but caused the loss of peel green, titratable acidity and weight. This work investigated the effects of hot air treatment combined with chitosan (CTS) coating on the ripening, quality and decay development for Gala apple fruits. Compared with fruits heat-treat alone, fruits heat-treated before CTS coating (heat treatment + CTS) preserved original peel color, maintained titratable acidity and weight, completely control decay development and showed the highest consumer acceptance after storage. The information obtained from this study suggested that this combined treatment may be a suitable method for the commercial application on Gala apple fruits.

The aim of the study was to simulate a hot-air-based treatment of the egg shell by a simplified finite element model. The calculated temperatures were compared with experimental data observed on an egg shell instrumented with thermocouples. A simple plant was used to make eggs roll while hot and cold air jets impinged the shell on opposite sides. The results have shown good agreement between calculated and observed temperatures on the inner part of the shell, despite the simplicity of the 2D numerical model. The observed temperature profiles, compatible both with albumen coagulation condition and shell pasteurization, support the hot air treatment as a possible and innovative surface decontamination technique for table eggs. PRACTICAL APPLICATIONS As hot-air decontamination is an innovative one, several tests will be necessary to assess the technique and to engineer the process. Unfortunately, each trial needs a number of microbial and quality tests requiring a remarkable amount of time and money. The numerical model made possible the testing of several thermal cycles, optimizing the value of the process parameters involved, reducing experimental effort. Moreover, the 2D model enhanced the advantages, with respect to the full 3D model, balancing an acceptable feasibility loss with much shorter calculus time.

Es werden Methoden und Kriterien zur Auswahl und Charakterisierung spezifisch wirkender Adsorbentien vorgestellt. Die Untersuchungen sollen ein neues multivariates Clusterverfahren fur Adsorptive verifizieren, das gegenuber den sonst ublichen Screeningverfahren den zeitlichen und materiellen Aufwand zur Auswahl optimierter Adsorbentien minimiert. Die Bedeutung der Adsorption von Wasserdampf und die Einflussmoglichkeiten durch Modifikationen der Adsorbentien werden vorgestellt. Abschliesend werden die wirtschaftlichen und technischen Vorteile adsorptiver Trennverfahren zur Abluftbehandlung in lebensmittelverarbeitenden Betrieben diskutiert. Methods and criteria for the evaluation and characterization of specific acting adsorbents are introduced. The results of the investigation are used to verify a new multivariate cluster analysis tool. Hence, in contrast to common screening procedures, the expenditure of time and effort for choosing optimized adsorbents can be minimized. The importance of the adsorption of water vapor and the possibilities to influence the adsorbents by modifications are presented. Finally, the economic and technical advantages of adsorption for exhaust air treatment within the food-processing industry are discussed.

Summary Apparent thermal diffusivity linear functions vs. product temperature were estimated for pork cooked under two different treatments (forced convection, FC and forced convection/steam combined, FC/S) at 100, 110, 120 and 140 °C by means of experimental time–temperature data and a developed finite-difference algorithm. Slope and intercept of each function were employed to calculate apparent thermal diffusivity at 40, 55 and 70 °C. Generally, FC/S treatments gave significantly higher apparent thermal diffusivities in comparison with FC conditions. Apparent thermal diffusivities were used to develop a model for cooking time and final core temperature prediction on the basis of oven setting. The model was validated by means of additional cooking tests performed at different temperatures of those employed for model development. Root mean square error values lower than 3.8 °C were obtained comparing predicted and experimental temperature profiles. Percentage errors lower than 3.1% and 3.5% were, respectively, obtained for cooking times and final core temperatures.

BACKGOUND: Chinese bayberry is susceptible to microbial decay during postharvest handling and storage. To search for effective alternatives to currently used fungicides for disease control, the efficacy of hot air (HA) treatment at 48 °C for 3 h alone or in combination with nano-packing (NP) containing nano-TiO2 and nano-Ag in controlling green mould decay caused by Penicillium citrinum and natural decay, and their effects on fruit quality in harvested Chinese bayberries were investigated in this study. RESULTS: The combined treatment of HA and NP resulted in a remarkably improved control of green mould and natural decay in Chinese bayberries compared with treatment of HA or NP alone. The in vitro growth of P. citrinum was significantly inhibited by individual HA or NP. In addition, HA in combination with NP showed interactive effect on inhibiting fruit respiration, ethylene production and membrane lipid peroxidation, and maintained higher fruit firmness and DPPH radical scavenging activity. CONCLUSION: These results suggest that a combination of HA treatment and NP may be a useful technique to reduce fruit decay and maintain quality in Chinese bayberries during postharvest storage and retail conditions. Copyright © 2010 Society of Chemical Industry

BACKGROUND: Two-phase partitioning bioreactors (TPPBs) are considered as a new technology for xenobiotic degradation in gaseous effluents. However, there is still a need for more knowledge on how to design and scale up TPPBs. The partitioning of the two phases remains a misunderstood method of research. In particular, the impact of pollutant (isopropylbenzene), biomass and surfactant extract needs to be better evaluated. RESULTS: An adapted scale-down apparatus has been developed in order to quantify the speed of phase partitioning (SPP) into a plug flow section. First, it was shown that isopropylbenzene (IPB) does not destabilise the system more significantly. Second, respectively 0.5 g L -1 and 0.05 g L -1 of biomass and surfactant extract, separately or in mixture, were sufficient to ensure the stability of the two-phase system. Finally, a 100 m 3 limit of scaling-up was suggested on the basis of the circulation time comparison. CONCLUSION: The scaling up of an aqueous-silicone oil TPPB was found to be definitely conceivable when the presence of biotic compounds were considered. However, further considerations are needed to verify our assumptions, in particular by taking into account the velocity field pattern in full-scale bioreactors and reproduce it in laboratory-scale apparatus.

BACKGROUND: Kinetic parameters used for modelling air biofilters are commonly determined by growing microorganisms in suspended cultures. However, they are not representative of phenomena occurring in a biofilm. There is need for new methods for calculating the true kinetics of pollutant degradation in an air biofilter. RESULTS: An experimental method for calculating the kinetic parameters of a microbial consortium which degrades methanol in an air treatment biofilter was developed. The kinetic parameters were calculated by taking biomass from biofilters packed with clay spheres or compost pellets. The kinetic runs were carried out in batch bioreactors at a constant temperature of 25 °C. The results obtained show that the maximum specific growth rate of microorganisms developed in the biofilter packed with clay spheres was twice as high as that packed with compost pellets; 0.233 h -1 for clay spheres and 0.129 h -1 for compost pellets. For both biofilters, the specific methanol biodegradation increased with methanol concentration in the biofilm, whereas carbon dioxide production was not a function of this parameter. CONCLUSION: Results show that for both biofilters, the Monod model fitted to the specific growth rate and the microbial consortium did not include any inhibition over the entire range of methanol concentrations tested.

The sea provides a large variety of seaweeds that, because of their chemical composition, are fantastic precursors of nanotextured carbons. The carbons are obtained by the simple pyrolysis of the seaweeds under a nitrogen atmosphere between 600 and 900 °C, followed by rinsing the product in slightly acidic water. Depending on the origin of the seaweed and on the pyrolysis conditions, the synthesis may be oriented to give an oxygen-enriched carbon or to give a tuned micro/mesoporous carbon. The samples with a rich oxygenated surface functionality are excellent as supercapacitor electrodes in an aqueous medium whereas the perfectly tuned porous carbons are directly applicable for organic media. In both cases, the specific surface area of the attained carbons does not exceed 1300 m2 g−1, which results in high-density materials. As a consequence, the volumetric capacitance is very high, making these materials more interesting than activated carbons from the point of view of developing small and compact electric power sources. Such versatile carbons, obtained by a simple, ecological, and cheap process, could be well used for environment remediation such as water and air treatment.

BACKGROUND: Postharvest decay and softening are the major factors limiting the extension of storage life of Chinese bayberry fruit. To evaluate the effects of hot air treatment (HAT) on Chinese bayberry fruit, fruits were stored at 2 °C after exposure to 20 °C (control), 40 °C (HAT40), 45 °C (HAT45) or 50 °C (HAT50) hot air for 3 h. The effects of HAT on firmness, disease incidence, soluble solid content (SSC), titratable acidity (TA), respiration, ethylene production, pectic substances and activities of pectinmethylesterase (PME) and polygalacturonase (PG) were examined. RESULTS: HAT inhibited decrease in firmness, SSC and TA and retarded increase in disease incidence, while it promoted decrease in respiration rate and ethylene production. HAT suppressed the activities of PME and PG, which resulted in delaying the depolymerisation of chelator-soluble and alkali-soluble pectic substances and reducing the increase in water-soluble pectic substances compared with control fruits. CONCLUSION: The present findings show that HAT can maintain postharvest quality and delay ripening of Chinese bayberry fruit and suggest that HAT could be considered for commercial use to extend the postharvest life of Chinese bayberry fruit. Copyright © 2008 Society of Chemical Industry

Biodegradable atmospheric pollutants, released at low to moderate concentrations, can be removed by biofiltration. In this work, a laboratory-scale compost-based biofilter has been evaluated for the removal of high levels of toluene in air (∼ 4.0 g.m−3). By applying a variable nitrogen input in the irrigation solution, it was shown that the biodegradation extent can be controlled through the nutrient supply. The maximum elimination capacity achieved was 135 g.m−3.h−1, for a N-concentration of 3.0 g of N.L−1. A quantitative analysis of the bioreaction aspects (stoichiometry, temperature) led to the determination of the water flow rates associated with the toluene oxidation. Thus, it was estimated that some 530 to 800 g of water.day−1 were lost at the bioreactor outlet, but were balanced by the irrigation system. Les polluants atmospheriques, emis a de faibles a moyennes concentrations, peuvent etre elimines par biofiltration. Dans ce travail, un biofiltre a base de compost a ete teste pour l'elimination de fortes concentrations de toluene dans l'air (∼ 4.0 g.m−3). L'ajout de quantites variables d'azote, via la solution nutritive, a montre que la reaction de biodegradation peut etre controlee par l'apport nutritionnel. La capacite d'elimination maximale obtenue etait de 135 g.m−3.h−1, pour une concentration d'azote de 3.0 g of N.L−1. Une analyse quantitative des aspects reactionnels (stœchiometrie, temperature) a conduit a la determination des quantites d'eau generees par l'oxydation du toluene. Ainsi, il a ete estime que quelques 530 a 800 g d'eau par jour etaient perdus par le bioreacteur, sous forme de vapeur, mais que ces pertes etaient contrebalancees par l'irrigation quotidienne du systeme.

Summary The efficacy of five non-chemical weed control methods for reducing weed cover on traffic islands was investigated in the growing season of 2004. Three trial sites were divided into six treatment areas which were treated with either flame, steam, hot air, hot water, brushes or left untreated. The treatments were carried out at regular intervals throughout the growing season. The percentage weed cover was measured every second week using a 75 × 75 cm quadratic frame with 100 squares. In the control areas, a rapid increase in weed cover was observed, whereas all treatments reduced weed cover. Hot water was the most effective method, although not significantly better than hot air or steam. Hot air treatment was more effective than brushing, whereas hot water was more effective than both flaming and brushing. The doses that were used were relatively high (150–355 kg ha−1), partly because of the irregular shape of the traffic islands and the treatment intervals were quite short in comparison with those in similar studies. However, the treatments could keep down the weeds only to a certain extent. The present knowledge of the efficacy of various weed control methods, as well as an increase in our knowledge of adequate treatment intervals, supports an optimisation of hard-surface weed control. Data and experience gained from these trials were used to develop further calibrated application studies.

BACKGROUND: To investigate the microbial degradation performance of organic pollutants in the atmosphere using a biotrickling filter, two microorganism strains, Bacillus cereus S1 and Bacillus cereus S2, were selected, identified and inoculated into a twin biotrickling filter for comparison. RESULTS: Both strains showed good performance towards the degradation of model organic pollutants when gas flow rates ranged from 100 to 600 L h−1. For S1, the total maximum removal efficiency (RE) of toluene was maintained nearly 100% not only at gas flow rates of 100 L h−1 corresponding to empty bed residence time (EBRT) 199.44 s, but also at gas flow rates of 200 L h−1 (EBRT = 99.72 s) and 300 L h−1 (EBRT = 66.48 s). However, S2 had a much lower degradation capability; near 100% removal efficiency was obtained only at the gas flow rate of 100 L h−1 although both bacteria belong to the same Bacillus cereus. With further increase in gas flow rate, the total REs for both S1 and S2 decreased slightly at first and then dropped sharply to 46% and 35%, respectively, at an EBRT of 33.24 s, corresponding to a gas flow rate of 600 L h−1. Starvation for between 2 and 10 days resulted in the re-acclimation times of both strains ranging between 1.0 and 15.5 h. CONCLUSION: Strain S1 would be a better choice for inoculation into a biotrickling filter than strain S2, because of its much higher toluene removal capacity and rapid recovery to full performance. Copyright © 2008 Society of Chemical Industry

The tools for optimal design of photocatalytic air purifiers are still being established. In this article, the optimal design of monolith photocatalytic reactors irradiated by cylindrical UV lamps was investigated. The radiative transfer equation in dimensionless monoliths was solved by the Monte-Carlo method to yield the radiation field in the reactor. The effect of the dimensionless design parameters, monolith aspect ratio, geometric ratios, catalyst reflectivity and number of lamps were investigated and correlated in terms of photon absorption efficiency (ϕ), uniformity of radiation distribution (η), and overall monolith photonic efficiency (Φ = η ϕ). Optimal design is achieved for aspect ratios of 2.5 and monolith-to-lamp-length ratios in the range from 1 to 1.1. The largest number of lamps compatible with uniform air distribution over the monoliths should always be used. The optimal monolith-to-lamp-distance ratio, βoptimum, was correlated as: [βoptimum = 1.698 (n + 1) − 0.279],where n is the number of lamps. © 2007 American Institute of Chemical Engineers AIChE J, 2007

This work was intended to investigate the effect of thermal treatment (by immersion or heated air) on quality attributes of pre‐cut celery stored at 0 °C for 21 days. The evolution of organoleptic characteristics, weight loss, surface color, chlorophyll content, texture and microbiological counts were determined. Quality of cut celery mostly maintained its initial level up to 14 days at 0 °C, regardless of the treatment applied. The control and heated‐air‐treated samples experienced a similar evolution of surface color, chlorophyll content, texture and microbial counts. There was a slight advantage of the heated air treatment compared to the control, as measured by sensory parameters. The immersion treatment allowed a better retention of the original color and the total chlorophyll content of pieces. However, after 14 days at 0 °C, a more noticeable tissue softening along with rapid microbial development was observed. Copyright © 2007 Society of Chemical Industry Fil: Viña, Sonia Zulma. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina Fil: Lopez Osornio, Maria de Las Mercedes. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina Fil: Chaves, Alicia Raquel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina

A biotrickling filter (BTF) for treating high ethanol loads was operated for one year and the effect of operating conditions was studied. The BTF was operated in a range of ethanol inlet concentrations of 0.2–15.0 g m−3 and at three different residence times (30, 65 and 130 s). The experiments show that removal efficiency decreased with increasing ethanol inlet concentration and decreasing air residence time. Removal efficiency varied in the range of 60–100%. A maximum elimination capacity of 970 g m−3 h−1 was obtained for an inlet load of 1610 g m−3 h−1. At a constant residence time, the carbon dioxide (CO2) production rate varied with ethanol inlet concentration. BTF presented the maximum CO2 production rate in the range of inlet concentration of 3.0–7.0 g m−3. Two strategies for controlling biomass accumulation were applied: one consisted in periodical washing; the other combined periodical washing with nutrient starvation by consuming less water and energy. Both strategies led to maintaining the BTF stable, with high adaptability and reproducibility. Copyright © 2007 Society of Chemical Industry

In recent years, special environmental concern is directed towards controlling the emission of fine particles (from 0.1 to 1.0 μm). These fine particles possibly cause serious health hazards because of heavy metals and toxic compounds adsbjrbed on the particles. To improve the collection efficiency of fine particles, the electrostatic flocking technique has been employed in this study. This technique is based on increasing the surface area of the collecting electrode and on producing a gradient force at the tip of fibers to suppress the re-entrainment. In this article, an experimental study was perftrttned to evaluate the effect of fine fibers on the collection efficiency of fine particles using the ESP with electrostatic floddng electrodes as collecting plates. The ESP achieved a collection efficiency of about 95% at a d.c. voltage of 9 kV, which was higher than that of flat-plate electrode for fine particles (0.3-0.5 μmin diameter) with a short residence time (0.06 s). We confirmed that the fine particles agglomerated at the tip of the flocking fibers. These results indicate that the new type of ESP examined in this study is effective to improve the removal performance of fine particles.

A hot air treatment was applied to broccoli (Brassica oleracea L. var. italica) florets and its effect on chlorophyll catabolism during postharvest senescence was analyzed. Florets were treated at 48°C for 3 h and then placed in darkness at 20°C. During storage, the yellowing of florets occurred simultaneously with a decrease in chlorophylls and an increase in pheophytins. Heat treatment delayed the appearance of yellowing by 2-3 days and a similar extension of shelf-life could be inferred. Also, the treatment delayed the onset of chlorophyll catabolism and slowed both the rate of chlorophyll a degradation and pheophytin accumulation. No effect on chlorophyll b degradation was found. Chlorophyllase and Mg-dechelatase activities increased from the first day of storage in untreated florets, whereas peroxidase-linked chlorophyll bleaching activity increased from day 3. In heat-treated florets, chlorophyllase activity did not increase until day 2 and then increased at lower rate than in controls. Mg-dechelatase and peroxidase-linked chlorophyll bleaching activities were similar in treated and control florets during the first 2 days of storage, but thereafter the activity of both enzymes was lower in heat-treated samples. In conclusion, a treatment at 48°C for 3 h delayed chlorophyll a catabolism in broccoli during postharvest senescence and decreased the activities of chlorophyllase, Mg-dechelatase and peroxidase, three of the enzymes probably involved in chlorophyll degradation in plants. © 2006 Society of Chemical Industry. Fil: Costa, M.lorenza. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina Fil: Civello, Pedro Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentina Fil: Chaves, Alicia Raquel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina Fil: Martinez, Gustavo Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentina

Coupling UV photolysis and biofiltration was evaluated as an effective treatment strategy for the enhanced degradation of hardly biodegradable aromatic volatile organic compounds (VOCs). o-Xylene, a recalcitrant and poorly water-soluble VOC, was used as a model compound and treated in two parallel treatment systems with and without UV pretreatment. Contaminated streams with flow rates of 0.186–0.384 m3 h−1 and inlet o-xylene concentrations of up to 0.22 g m−3 were passed through the treatment system. About 20% (between 10 and 35%) of o-xylene was converted into water-soluble intermediates during the UV photolysis stage, which partially oxidized o-xylene to more water-soluble and biodegradable byproducts. The untreated contaminant along with the byproducts of UV photolysis was then removed effectively in the biofiltration stage, with improvements of up to 100% compared with the control biofiltration process. The results suggested that combined UV photolysis–biofiltration is promising as an effective technique to eliminate hydrophobic and recalcitrant organic compounds from contaminated air steams. Copyright © 2005 Society of Chemical Industry

“Rhapsody” tomatoes were not heated or heated in air at 34 or 38C and 95% relative humidity (RH) for 24 h then stored at 4 or 20C for up to 4 weeks. The fruits were severely injured by 38C exposure, while those heated at 34C were only slightly injured. Heated fruit had more weight loss than control fruit. Nonheated fruit and those heated at 34C developed the best color compared with fruit heated at 38C. There were no differences in chlorophyll degradation between heated and nonheated fruit stored at 4C; however, fruits that were not heated and stored at 20C were the only ones with chlorophyll that degraded completely. Fruit stored at 20C developed a high quantity of lycopene andβ-carotene, with the highest level obtained in fruit heated at 34C and stored at 20C. Fruit stored at 4C almost did not develop any carotenoids.

Sink activity of fruits had been suggested to vary depending on transpiration of fruits. In this study, the effect of transpiration on dry matter accumulation was evaluated in tomato (Lycopersicon esculentum Mill.). Fruits of cv. Saturn at 14 days after anthesis were enclosed in chambers and aerated with dried ( 90% RH) air. These treatments did not cause any significant differences in fruit fresh weight, dry weight, percentage of dry matter, and concentration of soluble sugars within 5 days of the treatment, or the import of 14 C within 18 h after the application of 14 CO 2 to the source leaves. However, displacement transducer measurement of each fruit showed a 40% reduction in growth rate in response to exchange of moistened air with dried air. When fruits of cv. Momotaro were exposed to transpiration treatments from the beginning of visible fruit enlargement until the ripening stage, the fruits exhibited 20% reduction in growth and lower accumulation of dry matter at harvest following treatment with dried air. These results suggested that higher transpiration reduced both water accumulation and dry matter accumulation. In contrast, when fruit growth was mechanically restricted by enclosing the fruits in a chamber packed with glass beads, and dried or moistened air was passed through the spaces between the glass beads, fruits exhibited higher dry matter accumulation under dried air treatment conditions. The results show that only under artificial conditions would transpiration of fruits potentially drive carbohydrate transport; it does not serve as a limiting step of carbohydrate transport to tomato fruits under normal circumstances.

Treatments with hot air were applied to broccoli (Brassica oleracea L) florets to investigate the effect on several quality and senescence parameters. To select the optimum treatment, florets were treated with different combinations of time/temperature ranging from 1 to 3h and 37 to 50 ◦ C and then placed in darkness at 20 ◦ C. Most treatments delayed yellowing and loss of chlorophylls, except those performed at 37 ◦ C, which accelerated senescence. Treatment at 48 ◦ C for 3h caused the highest delay in chlorophyll loss and was chosen to analyse its effect on quality and senescence. Non-treated florets showed yellowing and reduced their chlorophyll content during storage. Heat treatment delayed the onset of chlorophyll catabolism by 1day and slowed down the rate of degradation. Treated florets also showed lower losses of total sugars and proteins and an inhibition of protein solubilisation. Control heads showed an increment in CO2 production, which was not detected in heat-treated florets. Total antioxidants decreased and thiobarbituric acid-reactive substances (TBARS) increased during storage. The treatment delayed the decrease in antioxidant content and inhibited the increment in TBARS. In conclusion, treatment at 48 ◦ C for 3h delayed broccoli senescence at 20 ◦ C and contributed to maintaining an overall better quality of the product.  2005 Society of Chemical Industry

A photocatalytic reactor was simulated through computational fluid dynamics (CFD) with surface reaction for trichloroethylene (TCE) oxidation at various pollutant concentrations, flow rates, and reactor lengths. The results were compared with those from experiments. The experimental work involved using a differential photoreactor for kinetics studies and an annular flow photoreactor for overall removal investigations under various conditions. The modeling predictions agreed closely with the experimental data within the range in which results were examined. The modeling results indicated significant radial TCE concentration gradient and nonuniform flow distributions in the annular photoreactor. CFD was applied to predict the performance of a number of UV photocatalytic reactor design concepts, to study the impacts of some design parameters on the reactor efficiency. The modeling results demonstrated that under similar flow rate conditions, the thickness of the contaminated air layer flowing over the photocatalyst surface could substantially influence the reactor performance. Thinner contaminated air layers provided more uniform radial concentration distribution of TCE and improved the reactor performance.

Laboratory experiments were conducted to evaluate the potential to utilize ultraviolet (UV) photooxidation as a pre-treatment to render recalcitrant volatile organic compounds into more biodegradable compounds. α-Pinene was selected due to its low water solubility and low biodegradability. α-Pinene-contaminated gaseous streams with inlet loadings between 250 and 2500 g m−3 h−1 were passed through an annular reactor equipped with a UV lamp that emitted light at 254 nm and 185 nm wavelengths. The outlet stream containing UV photooxidation intermediates was then sparged through nanopure water that was then analyzed for its total organic carbon (TOC) content and subjected to batch biodegradability tests. UV photooxidation effectively degraded α-pinene with a maximum removal rate of about 700 g m−3 h−1. The removal rate followed first order kinetics at low inlet loadings (less than 1200 g m−3 h−1) and approached zero order behavior at higher inlet loadings. The principal oxidizing species in the reactor was ozone. Of the total α-pinene removed, measured as TOC, 50% was converted to water-soluble and more biodegradable intermediates. The biodegradability of the resultant intermediates was similar to that of methyl ethyl ketone (MEK), which is 3–30 times more biodegradable than α-pinene. These results show that the use of UV photooxidation is a promising and effective pre-treatment technique for enhancing the biodegradability of hydrophobic and recalcitrant organic compounds such as α-pinene. Copyright © 2004 Society of Chemical Industry

‘Hass’ avocado fruit were heated with dry (50% RH) or moist (95 % RH) forced air at 38C for 6 h and then stored at 5C and 85% RH for up to 8 weeks. Fruit were evaluated weekly for quality and for the content of three triglycerides and three tocopherols. Heated fruit had higher weight loss. The nonheated fruit and those heated with dry air displayed the best external quality. Fruit heated with dry air exhibited the best internal quality and the lowest chilling injury incidence. The respiration rate was more intense in fruit heated with moist air. Fruit firmness immediately afer harvest was 51 N, but decreased to less than 20 N at the end of the storage period in the three treatments. The analysis of triglycerides andtocopherols showed that the 1,2-Dilinoleil-3-Oleil-Glycerol and a-tocopherol were the most abundant compounds. Therefore, postharvest treatment with dty forced hot air before storage or transport reduces the incidence of chilling injury, and decreases quality deterioration in ‘Hass ’ avocado fruit.

Papaya (Carica papaya L.) fruit is very perishable with a maximum postharvest life of 4 weeks. The effect of forced moist (100% RH) or dry (50%) hot air with or without Thiabenduzole (TBZ at 1.2 g active ingredient&) on the chilling injury (CI), fungi development and quality of ‘Maradol’ papaya fruit stored at 5C or 20C for up to 42 days was investigated. Moist hot air at 48.SC or 50C for 4 h caused fruit injury. Dry air at 48.5C for 4 h, alone or in combination with TBZ, decreased CI intensity and fungi development, and the best effect was achieved by combining dry heat treatment and TBZ, without causing negative fleets on fruit quality and without causing heat injury. Hot air treatment, especially in combination with TBZ, decreased growth of inoculated Colletotrichum gloeosporioides. Trehalose was not detected in papaya, probably due to the presence of trehalase. Hot water treatment, with or without TBZ, did not cause any negative effect on the content of @-carotene and lycopene.

In this work, the removal of monochlorobenzene (CB) vapors from air was studied, for the first time, in a non-inoculated, laboratory-scale, aerobic biofilter. The influence of three parameters on the bioprocess has been evaluated: the rate of nitrogen supplied to the bed, the inlet concentration of CB, and the flow rate. The CB inlet concentration was varied between 0.3 and 3.2 g m−3, at a constant flow rate of 1.0 m3 h−1. Removal rates of greater than 90% were achieved for CB inlet concentrations of up to 1.2 g m−3. Then the flow rate was varied from 0.5 to 3.0 m3 h−1 with a constant inlet concentration (1.2 g m−3). Maximum elimination capacities (70 g m−3 h−1) were reached for contact times of greater than 60 s. The study of varying flow rates also permitted evaluation of a first order macrokinetic constant (1.1 × 10−2 s−1) for the CB biodegradation. Finally, the optimum nitrogen input value was found to lie between 0.3 and 0.4 g N h−1 and gave rise to elimination capacities as high as 70 g m−3 h−1 for an inlet load of near 80 g m−3 h−1. Copyright © 2003 Society of Chemical Industry

In this report, gaseous toluene biodegradation results in a flat composite membrane reactor inoculated with Pseudomonas putida TVA8 are presented. Preliminary abiotic experiments showed that transport of toluene through the membrane was linearly and negatively correlated with the gas residence time (tau). During a 339-day biofiltration experiment, the influence of gas residence time (2-24 sec) and mass loading rate (B(v); 10-483 g x m(-3) h(-1)) on the toluene elimination capacity was investigated. A maximum elimination capacity (EC(max)) of 397 g x m(-3) h(-1) was achieved at tau = 24 sec and B(v) = 473 g x m(-3) h(-1). Expressed per unit membrane area, the EC(m,max) was 0.793 g x m(-2) h(-1), which is five times higher than results obtained with other membrane bioreactor experiments in the same range of loading rates. At low gas residence times, reactor performance was limited by mass transfer. Toluene concentration profiles along the membrane were measured for several biotic and abiotic conditions. For inlet concentrations (C(in)) up to 1 g x m(-3), more than 90% was eliminated at 15 cm from the reactor inlet. For C(in) > 1.65 g x m(-3), longer membranes are necessary to obtain these high removal efficiencies.

This study determined the effectiveness of components of a germicidal air-cleaning system involving filtration, electrostatic polarization, and UV light on the reduction of airborne bacteria and molds. The filter alone, filter and electrostatic polarization combined, and the filter, electrostatic polarization, and UV light were found to be effective (P < 0.05) in reducing a given concentration of M. luteus and S. marcescens by 90 to 92%. The same components were also found to be effective (P < 0.05) in reducing indigenous airborne bacteria and molds from ambient air in processing plant production conditions by 62 to 77% after only 1 pass through the filtration system. A germicidal air-filtration system utilizing electrostatic polarization and ultraviolet light can be used to reduce the chance of contaminating surfaces with airborne bacteria and molds.

Treatment of methyl tertiary-butyl ether (MTBE) from contaminated surface and ground water supplies presents specific challenges due to the physicochemical properties of MTBE that depend strongly on its hydrophilic nature, and translate into a high solubility in water, and low Henry's constant and low affinity for common adsorbents. We evaluate four treatment technologies-air stripping, granular activated carbon (GAC), hydrophobic hollow fiber membranes, and advanced oxidation processes (AOP)-using ozone or ozone/hydrogen peroxide. Experimental work was carried out to generate parameter values necessary for the design of these processes. Ten different flow rates/concentration combinations were evaluated in our designs to cover the range from high flow rate/low concentration typical of surface water and ground water drinking water supplies to low flow rate/high concentration typical of ground water remediation sites. For all cases, the processes were designed to produce effluent water of 5 μg/L or less. Capital costs and operation and maintenance costs were determined at the feasibility level by using standard engineering estimating practices. Air stripping is the lowest cost technology for high flow rales (100 to 1000 gpm) if no air treatment is required. Hollow fiber membranes are the lowest cost technology for flow rates of 10 to 100 gpm if no air treatment is required, which is typical at these low flow rates. GAC will be most costeffective at all flow rates if air treatment is required and the influent water has low levels of other organic compounds. AOP using ozone or ozone/hydrogen peroxide is in all cases more expensive than the alternative technologies, and there are sufficient uncertainties at this point with respect to byproducts of AOP to warrant further study of this technology. The cost of treating MTBE-contaminated water for conventional technologies such as air stripping and GAC is 40% to 80% higher than treating water contaminated only with other hydrocarbons such as benzene.

In the work reported here, selected aspects of the dynamic behavior of biofilters for waste air treatment have been investigated. Emphasis was placed on transient state elimination of mixtures of methyl ethyl ketone (MEK) and methyl isobutyl ketone (MIBK) vapors and on explanation of the observed phenomena. The initial startup, the response of the biofilter to step changes in the pollutant loadings, responses to pollutant pulses, restarting after starvation, and the influence of step changes in gaseous phase oxygen partial pressure are presented and discussed.

‘Northeaster’strawbenies were heated with moist hot air at 36, 39, 42, 45, 50 and 55C for 0, 20,40, 60, 80 or 100 min. Fruit were injured when exposed to temperatures 50C or higher, or durations of 60 min or longer at 45C. Treatment at 45C for 40 min or at 42C for 60-100 min resulted in the least decay incidence after 5 days at OC, 3 days at IOC, and I day at 20C. Heated strawberries in general had lower titratable acidig, higher soluble solitis content and higher levels offictose, glucose, and sucrose than nonheated samples. Heated fruit also had a higher soluble soliddacid ratio, but lower citric acid and malic acid content. The lightness measurements, L*, and chroma values, C*, were decreased by moist hot air treatment and the fruit were duller and less bright in appearance after heat treatment. Strawberries heated at 39C or lower temperatures had no discernable differences from nontreated fruit in quality attributes measured. However, fruit treated with 45C for 40 rnin or 42C for 60-1 00 rnin maintained better postharvest quality than other treatments.