463 research outputs found

    Electrochemical processing of solid waste

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    The investigation into electrolysis as a means of waste treatment and recycling on manned space missions is described. The electrochemical reactions of an artificial fecal waste mixture was examined. Waste electrolysis experiments were performed in a single compartment reactor, on platinum electrodes, to determine conditions likely to maximize the efficiency of oxidation of fecal waste material to CO2. The maximum current efficiencies for artificial fecal waste electrolysis to CO2 was found to be around 50 percent in the test apparatus. Experiments involving fecal waste oxidation on platinum indicates that electrodes with a higher overvoltage for oxygen evolution such as lead dioxide will give a larger effective potential range for organic oxidation reactions. An electrochemical packed column reactor was constructed with lead dioxide as electrode material. Preliminary experiments were performed using a packed-bed reactor and continuous flow techniques showing this system may be effective in complete oxidation of fecal material. The addition of redox mediator Ce(3+)/Ce(4+) enhances the oxidation process of biomass components. Scientific literature relevant to biomass and fecal waste electrolysis were reviewed

    Electrochemical incineration of wastes

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    The disposal of domestic organic waste in its raw state is a matter of increasing public concern. Earlier, it was regarded as permissible to reject wastes into the apparently infinite sink of the sea but, during the last 20 years, it has become clear that this is environmentally unacceptable. On the other hand, sewage farms and drainage systems for cities and for new housing developments are cumbersome and expensive to build and operate. New technology whereby waste is converted to acceptable chemicals and pollution-free gases at site is desirable. The problems posed by wastes are particularly demanding in space vehicles where it is desirable to utilize treatments that will convert wastes into chemicals that can be recycled. In this situation, the combustion of waste is undesirable due to the inevitable presence of oxides of nitrogen and carbon monoxide in the effluent gases. Here, in particular, electrochemical techniques offer several advantages including the low temperatures which may be used and the absence of any NO and CO in the evolved gases. Work done in this area was restricted to technological papers, and the present report is an attempt to give a more fundamental basis to the early stages of a potentially valuable technology

    Effect of Isosporiasis Prevention with Toltrazuril on Long-Term Pig Performance

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    The efficacy of toltrazuril treatment was assessed in two experiments in Polish swine herds. Experiment 1 included a toltrazuril treatment group, Group A (n = 410), and untreated control, Group B (n = 386). Time to sale in Group A was 108 days versus 120 days for Group B, with average body weights at sale of 114.2 kg and 108.8 kg, respectively (P < 0.05). In experiment 2, the health status and body weight gain of 238 piglets treated with toltrazuril (Group D) were compared to 235 untreated piglets (Group K). A similar difference was observed in average body weights of slaughtered animals, being on average 104 kg in Group D and 101 kg in Group K (P < 0.01). Animals from Group D were slaughtered 5 days earlier than animals from Group K (day 166 versus day 171). Data from clinical trials suggest treatment of coccidiosis with toltrazuril offering potential for improved animal welfare and yields, however this has remained unproven in field conditions in large swine production facilities. The present study confirms the efficacy of toltrazuril treatment when used in the field and the subsequent positive impact on time to weaning, time to market, and on weight gain at all time points

    Epidemiological study of canine trypanosomosis in an urban area of Ivory Coast

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    Following confirmed cases of trypanosomosis in military working dogs, c cross-sectional study was undertaken to evaluate the source of infection and determine the prevalence of canine infection with Trypanosoma congolense in the urban focus of Abidjan, Ivory Coast. Blood from 123 dogs were collected and subjected to PCR using specific primers for Trypanosoma congolense "forest type". In addition, an entomological study was conducted in an urban area near the forest surronding the military camp. The observed prevalence was 30.1% end PCR positivity to Trypanosoma congolense was not significantly associated with sex or age of animals. This study demonstrates the high contamination rate of dogs in enzootic zones, the potential risk of introduction of the disease in free animal populations and the ability of Glossina palpalis to adopt to urban areas and to transmit trypanosomosis in such areas. The factors leading to a possible emergence of canine trypanosomiasis in enzootic zones need further investigations

    Persistent Atrial Fibrillation: The Role of Left Atrial Posterior Wall Isolation and Ablation Strategies.

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    Atrial fibrillation (AF) is a global disease with rapidly rising incidence and prevalence. It is associated with a higher risk of stroke, dementia, cognitive decline, sudden and cardiovascular death, heart failure and impairment in quality of life. The disease is a major burden on the healthcare system. Paroxysmal AF is typically managed with medications or endocardial catheter ablation to good effect. However, a large proportion of patients with AF have persistent or long-standing persistent AF, which are more complex forms of the condition and thus more difficult to treat. This is in part due to the progressive electro-anatomical changes that occur with AF persistence and the spread of arrhythmogenic triggers and substrates outside of the pulmonary veins. The posterior wall of the left atrium is a common site for these changes and has become a target of ablation strategies to treat these more resistant forms of AF. In this review, we discuss the role of the posterior left atrial wall in persistent and long-standing persistent AF, the limitations of current endocardial-focused treatment strategies, and future perspectives on hybrid epicardial-endocardial approaches to posterior wall isolation or ablation

    Contribution à la dépollution d’un rejet textile par adsorption sur un coagulant à base du mélange fer/aluminium préparé par électrocoagulation

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    L&#8217;industrie textile consomme une grande quantit&#233; d&#8217;eau, g&#233;n&#233;rant ainsi des rejets liquides &#224; charge &#233;lev&#233;e en divers types de polluants. Ces derniers produisent des effets nocifs sur l&#8217;environnement. Ce travail s&#8217;int&#233;resse &#224; la d&#233;pollution d&#8217;un rejet d&#8217;une industrie textile, par addition d&#8217;un coagulant synth&#233;tique &#224; base de fer et d&#8217;aluminium, pr&#233;par&#233; par le proc&#233;d&#233; d&#8217;&#233;lectrocoagulation. Les r&#233;sultats ont montr&#233; que le traitement de ce rejet par ce coagulant, a permis d&#8217;atteindre un rendement d&#8217;&#233;limination des mati&#232;res colorantes de 83.37% en terme de demande chimique en oxyg&#232;ne (DCO).Mots cl&#233;s: traitement, hydroxyde, coagulation, demande chimique en oxyg&#232;n
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