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1.
Clin Ter ; 170(1): e19-e29, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31850480

RESUMO

Research into sexual aspects poses a fascinating challenge that is highly cogent to clinical profiling disciplines, but also constitutes a more 'narrative and culturally oriented' approach to medicine and psychology. Assessments of subjects affected by gender dysphoria and their internal, relational and sexual world is a still more complex task, since these are very distressing and tormented issues for the subjects under study. Psychodiagnostics can be an important element in the various investigative, evaluative and therapeutic pathways. The authors have focused attention on the TIPE (Test di Induzione PsicoErotica: PsychoErotic Induction Test), an Italian projective psychodiagnostic tool that is used to explore the psychoerotic fantasies of subjects affected by gender dysphoria. The TIPE tests protocols of two samples of subjects have been examined. They projected particularly rich narrative aspects of the subjects' psychoerotic imaginary world. The first sample, a clinical series, consisted of a total of eleven subjects, nine men and two women, mean age 43 years, who were undergoing assessment, firstly psychotherapeutic and then medicolegal, for sex rectification purposes; the second sample, the controls, consisted of fourteen subjects, nine men and five women, mean age 28 years, all heterosexual and with a problem-free history of sexual identity.


Assuntos
Literatura Erótica/psicologia , Fantasia , Disforia de Gênero/diagnóstico , Disforia de Gênero/psicologia , Identidade de Gênero , Heterossexualidade/psicologia , Comportamento Sexual/psicologia , Adulto , Feminino , Humanos , Itália , Masculino , Projetos de Pesquisa
2.
Environ Technol ; 38(11): 1452-1464, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27600950

RESUMO

In order to enhance anaerobic biodegradability of food waste (FW), thermal pretreatment was applied. The effectiveness in terms of biodegradability extent and process rate improvement was investigated. To this aim, Biomethane Potential tests were carried out under mesophilic and thermophilic conditions. The IWA anaerobic digestion Model 1 (ADM1), a powerful tool for modeling the anaerobic digestion (AD) of different substrates, was implemented to predict the methane production. Disintegration constant (k_dis) and maximum acetate uptake rate (km_ac) were identified as the most sensitive parameters and were calibrated over the observed methane production. Pretreatment improvement was more evident in enhancing parameters related to the process rate, such as solubilization extent (+153%) and disintegration constant (+18%), rather than increasing substrate biodegradability. Thermophilic conditions proved to be effective in speeding up the whole AD process, since all the kinetics were significantly improved (disintegration rate increased up to fivefold). Furthermore, it was demonstrated that, after k_dis and km_ac calibration, default thermophilic ADM1 parameters can be suitable to model FW digestion.


Assuntos
Metano/biossíntese , Modelos Teóricos , Temperatura , Gerenciamento de Resíduos/métodos , Anaerobiose , Serviços de Alimentação , Resíduos
3.
Environ Sci Pollut Res Int ; 23(5): 4585-93, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26520096

RESUMO

Separation between primary and secondary sludge treatment could be a valuable solution for sludge management. According to this approach, secondary sludge can be conveniently used in agriculture while primary sludge could be easily dried and incinerated. It follows that some concern may arise from incinerating primary sludge with respect to the current practice to incinerate mixed digested sludge. Incineration of primary and mixed digested municipal sludge was investigated with a lab-scale equipment in terms of emissions of products of incomplete combustion (PICs) during incineration failure modes. PICs can be grouped in three sub-categories, namely aliphatic hydrocarbons (alkanes and alkenes), compounds with a single aromatic ring, and polycyclic aromatic hydrocarbons (PAHs). After-burning temperature was the most important parameter to be controlled in order to minimize emissions of alkanes and alkenes. As for mono-aromatic compounds, benzene and toluene are the most thermally resistant compounds, and in some cases, an after-burning temperature of 1100 °C was not enough to get the complete destruction of benzene leading to a residual emission of 18 mg/kgsludge. PAHs showed an opposite trend with respect to aliphatic and mono-aromatic hydrocarbons being the thermal failure mode the main responsible of PIC emissions. A proper oxygen concentration is more important than elevated temperature thus reflecting the high thermal stability of PAHs. Overall, obtained results, even though obtained under flameless conditions that are different from those of the industrial plants, demonstrated that separation of primary and secondary sludge does not pose any drawbacks or concern regarding primary sludge being disposed of by incineration even though it is more contaminated than mixed digested sludge in terms of organic pollutants.


Assuntos
Incineração , Esgotos , Temperatura Alta , Hidrocarbonetos Aromáticos/química , Incineração/instrumentação , Hidrocarbonetos Policíclicos Aromáticos/química , Esgotos/química
6.
Environ Sci Pollut Res Int ; 22(10): 7203-15, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25598155

RESUMO

This paper describes the preliminary assessment of a platform of innovative upgrading solutions aimed at improving sludge management and resource recovery in wastewater treatment plants. The effectiveness of the upgrading solutions and the impacts of their integration in model reference plants have been evaluated by means of mass and energy balances on the whole treatment plant. Attention has been also paid to the fate of nitrogen and phosphorus in sludge processing and to their recycle back to the water line. Most of the upgrading options resulted in reduced production of dewatered sludge, which decreased from 45 to 56 g SS/(PE × day) in reference plants to 14-49 g SS/(PE × day) in the upgraded ones, with reduction up to 79% when wet oxidation was applied to the whole sludge production. The innovative upgrades generally entail an increased demand of electric energy from the grid, but energy recovery from biogas allowed to minimize the net energy consumption below 10 kWh/(PE × year) in the two most efficient solutions. In all other cases the net energy consumption was in the range of -11% and +28% of the reference scenarios.


Assuntos
Esgotos/análise , Eliminação de Resíduos Líquidos/métodos , Biocombustíveis/análise , Nitrogênio/análise , Fósforo/análise , Águas Residuárias/análise
7.
Water Res ; 68: 498-509, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25462756

RESUMO

Thermal hydrolysis pretreatment coupled with Thermophilic Anaerobic Digestion (TAD) for Waste Activated Sludge (WAS) treatment is a promising combination to improve biodegradation kinetics during stabilization. However, to date there is a limited knowledge of the anaerobic biomass composition and its impact on TAD process performances. In this study, the structure and dynamics of the microbial communities selected in two semi-continuous anaerobic digesters, fed with untreated and thermal pretreated sludge, were investigated. The systems were operated for 250 days at different organic loading rate. 16S rRNA gene clonal analysis and Fluorescence In Situ Hybridization (FISH) analyses allowed us to identify the majority of bacterial and archaeal populations. Proteolytic Coprothermobacter spp. and hydrogenotrophic Methanothermobacter spp. living in strict syntrophic association were found to dominate in TAD process. The establishment of a syntrophic proteolytic pathway was favoured by the high temperature of the process and enhanced by the thermal pretreatment of the feeding sludge. Proteolytic activity, alone or with thermal pretreatment, occurred during TAD as proven by increasing concentration of soluble ammonia and soluble COD (sCOD) during the process. However, the availability of a readily biodegradable substrate due to pretreatment allowed to significant sCOD removals (more than 55%) corresponding to higher biogas production in the reactor fed with thermal pretreated sludge. Microbial population dynamics analysed by FISH showed that Coprothermobacter and Methanothermobacter immediately established a stable syntrophic association in the reactor fed with pretreated sludge in line with the overall improved TAD performances observed under these conditions.


Assuntos
Archaea/genética , Bactérias/genética , Esgotos/microbiologia , Microbiologia da Água , Anaerobiose , Archaea/classificação , Archaea/metabolismo , Bactérias/classificação , Bactérias/metabolismo , Biodegradação Ambiental , Biomassa , Reatores Biológicos/microbiologia , Temperatura Alta , Hibridização in Situ Fluorescente , Metano/metabolismo , Methanobacteriaceae/genética , Methanobacteriaceae/metabolismo , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
8.
Environ Sci Pollut Res Int ; 22(10): 7237-47, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25233915

RESUMO

The present research aims at the evaluation of the hygienization performances of innovative sludge treatment processes applied for the separated treatment of secondary sludge. Namely, two digestion pretreatments (sonication and thermal hydrolysis) and two sequential biological processes (mesophilic/thermophilic and anaerobic/aerobic digestion) were compared to the mesophilic (MAD) and thermophilic anaerobic digestion (TAD). Microbial indicators (Escherichia coli, somatic coliphages and Clostridium perfringens spores) and pathogens (Salmonella and enteroviruses), which show different resistances to treatment processes, were monitored in untreated and treated sludge. Overall, microbial load in secondary sludge was shown to be similar or lower than previously reported in literature for mixed sludge. Notably, the anaerobic/aerobic digestion process increased the removal of E. coli and somatic coliphages compared to the simple MAD and always achieved the hygienization requirement (2-log-unit removal of E. coli) proposed by EU Commission in the 3rd Working Document on sludge (April 2000) for the use of treated sludges in agriculture with restriction on their application. The microbial quality limits for the unrestricted use of sludge in agriculture (no Salmonella in 50 g wet weight (WW) and E. coli <500 CFU/g) were always met when thermal digestion or pretreatment was applied; however, the required removal level (6-log-unit removal of E. coli) could not be assessed due to the low level of this microorganism in raw sludge. Observed levels of indicator removal showed a higher resistance of viral particles to thermal treatment compared with bacterial cells and confirmed the suitability of somatic coliphages as indicators in thermal treatment processes.


Assuntos
Bactérias/isolamento & purificação , Enterovirus/isolamento & purificação , Fertilizantes/análise , Esgotos/análise , Esgotos/microbiologia , Temperatura Alta , Hidrólise , Esgotos/virologia , Sonicação
9.
Environ Sci Pollut Res Int ; 22(10): 7248-56, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24906832

RESUMO

This study investigates for the first time, on laboratory scale, the possible application of an innovative enhanced stabilization process based on sequential mesophilic/thermophilic anaerobic digestion of waste-activated sludge, with low-energy sonication pretreatment. The first mesophilic digestion step was conducted at short hydraulic retention time (3-5 days), in order to favor volatile fatty acid production, followed by a longer thermophilic step of 10 days to enhance the bioconversion kinetics, assuring a complete pathogen removal. The high volatile solid removals, up to 55%, noticeably higher compared to the performances of a single-stage process carried out in same conditions, can guarantee the stability of the final digestate for land application. The ultrasonic pretreatment influenced significantly the fatty acid formation and composition during the first mesophilic step, improving consequently the thermophilic conversion of these compounds into methane. Methane yield from sonicated sludge digestion reached values up to 0.2 Nm(3)/kgVSfed. Positive energy balances highlighted the possible exploitation of this innovative two-stage digestion in place of conventional single-stage processes.


Assuntos
Esgotos/análise , Sonicação , Eliminação de Resíduos Líquidos/métodos , Bactérias Anaeróbias , Reatores Biológicos/microbiologia , Ácidos Graxos Voláteis/metabolismo , Metano/metabolismo , Modelos Teóricos
10.
Environ Sci Pollut Res Int ; 22(10): 7361-74, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24946701

RESUMO

This paper presents the current sewage sludge legislation in Europe and expected developments regarding the coming directives on the application of the "End-of-waste" criteria and on fertilizers. Discussion on sludge production and processing is also included. The Directive 86/278 has regulated the use in agriculture of residual sludge from domestic and urban wastewater. After 1986, this directive was transposed in the different member state legislation and currently the national limit values on heavy metals, some organic micropollutants and pathogens are placed in a rather wide range. This seems the inevitable consequence of different attitudes towards sludge management practices in the member states. The discussion by the European Joint Research Center (JRC) in Seville regarding application of end-of-waste criteria for compost and digestate has produced a final document (IPTS 2014) where sludge was excluded from the organic wastes admitted for producing an end-of-waste compost. Sludge processing in Europe seems addressed to different goals: sludge minimization, full stabilization and hygienization by thermal hydrolysis processes before anaerobic digestion, and on-site incineration by fluidized bed furnace. Thermophilic anaerobic digestion was applied with success on the Prague WWTP with a preliminary lysimeter centrifugation. Coming techniques, like wet oxidation and pyrolysis, are applied only on very few plants.


Assuntos
Esgotos/legislação & jurisprudência , Eliminação de Resíduos Líquidos/legislação & jurisprudência , Eliminação de Resíduos Líquidos/normas , Agricultura , União Europeia , Fertilizantes/análise , Hidrólise , Metais Pesados/análise , Esgotos/química , Eliminação de Resíduos Líquidos/métodos
11.
Environ Sci Pollut Res Int ; 22(10): 7216-35, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24903249

RESUMO

The European Union (EU) Project Routes aimed to discover new routes in sludge stabilization treatments leading to high-quality digested sludge, suitable for land application. In order to investigate the impact of different enhanced sludge stabilization processes such as (a) thermophilic digestion integrated with thermal hydrolysis pretreatment (TT), (b) sonication before mesophilic/thermophilic digestion (UMT), and (c) sequential anaerobic/aerobic digestion (AA) on digested sludge quality, a broad class of conventional and emerging organic micropollutants as well as ecotoxicity was analyzed, extending the assessment beyond the parameters typically considered (i.e., stability index and heavy metals). The stability index was improved by adding aerobic posttreatment or by operating dual-stage process but not by pretreatment integration. Filterability was worsened by thermophilic digestion, either alone (TT) or coupled with mesophilic digestion (UMT). The concentrations of heavy metals, present in ranking order Zn > Cu > Pb > Cr ~ Ni > Cd > Hg, were always below the current legal requirements for use on land and were not removed during the processes. Removals of conventional and emerging organic pollutants were greatly enhanced by performing double-stage digestion (UMT and AA treatment) compared to a single-stage process as TT; the same trend was found as regards toxicity reduction. Overall, all the digested sludges exhibited toxicity to the soil bacterium Arthrobacter globiformis at concentrations about factor 100 higher than the usual application rate of sludge to soil in Europe. For earthworms, a safety margin of factor 30 was generally achieved for all the digested samples.


Assuntos
Metais Pesados/análise , Esgotos/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Animais , Arthrobacter/efeitos dos fármacos , Arthrobacter/metabolismo , União Europeia , Metais Pesados/toxicidade , Oligoquetos/efeitos dos fármacos , Oligoquetos/metabolismo , Poluentes Químicos da Água/toxicidade
12.
Water Sci Technol ; 69(8): 1728-34, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24759535

RESUMO

The requirement for enhanced stabilization processes to obtain a more stable, pathogen-free sludge for agricultural use is an increasing challenge to comply with in the waste hierarchy. With this in mind, the Routes European project ('Novel processing routes for effective sewage sludge management') is addressed to assess innovative solutions with the aim of maximizing sludge quality and biological stability. In order to increase anaerobic stabilization performances, the sequential anerobic/aerobic process and the thermophilic digestion process, with or without integration of the thermal hydrolysis pre-treatment, were investigated as regards the effect on sludge stabilization, dewaterability and digestion performances. Thermal pre-treatment improved anaerobic digestion in terms of volatile solids reduction and biogas production, but digestate dewaterability worsened. Fluorescence in situ hybridization (FISH) quantification showed an increase of methanogens consistent with the increase of biogas produced. The aerobic post-treatment after mesophilic digestion had a beneficial effect on dewaterability and stability of the digested sludge even if was with a reduction of the potential energy recovery.


Assuntos
Reatores Biológicos , Esgotos/química , Eliminação de Resíduos Líquidos , Aerobiose , Anaerobiose
13.
Bioresour Technol ; 147: 623-626, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24035286

RESUMO

Olive husks, typical solid by-products from the olive oil industry, were selected to carry out anaerobic digestion tests. Before digestion, olive husks were subjected to ultrasonic or thermal pretreatments in order to release the organic matter into solution. Both sonication and thermal pretreatment allowed to solubilize the particulate matter with 22% and 72% increase in soluble organics of olive husks, respectively. Nevertheless, such pretreatments caused the release of unwanted molecules in solution, with the related risks of inhibition of the methanogenic process. Biochemical Methane Potential (BMP) tests on olive husks mixed with olive-mill wastewater and dairy wastewater, either pretreated or not, showed that ultrasound pretreatment resulted in 15% increase in volatile solids reduction and a 13% increase in biogas production, while after thermal pretreatment no benefits were observed.


Assuntos
Temperatura Alta , Olea/metabolismo , Ultrassom , Anaerobiose
14.
Bioresour Technol ; 143: 96-103, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23792658

RESUMO

The performance of thermophilic digestion of waste activated sludge, either untreated or thermal pretreated, was evaluated through semi-continuous tests carried out at organic loading rates in the range of 1-3.7 kg VS/m(3)d. Although the thermal pretreatment at T=134 °C proved to be effective in solubilizing organic matter, no significant gain in organics degradation was observed. However, the digestion of pretreated sludge showed significant soluble COD removal (more than 55%) whereas no removal occurred in control reactors. The lower the initial sludge biodegradability, the higher the efficiency of thermal pretreated digestion was observed, in particular as regards higher biogas and methane production rates with respect to the parallel untreated sludge digestion. Heat balance of the combined thermal hydrolysis/thermophilic digestion process, applied on full-scale scenarios, showed positive values for direct combustion of methane. In case of combined heat and power generation, attractive electric energy recoveries were obtained, with a positive heat balance at high load.


Assuntos
Temperatura Alta , Esgotos , Anaerobiose , Biodegradação Ambiental , Biocombustíveis , Hidrólise
15.
Environ Sci Pollut Res Int ; 20(9): 6256-65, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23589264

RESUMO

A 2-year sampling campaign was conducted in three wastewater treatment plants of various sizes in the Rome area to assess the occurrence of nutrients and micropollutants among primary, secondary and digested sludge. The primary purpose was to evaluate the quality of different sludge types and their suitability for agricultural use. Primary sludge was consistently more polluted than secondary in terms of organic micropollutants, whereas heavy metals partitioned equally among the sludge types. In digested sludge, the heavy metal concentrations were always below limit values proposed for agricultural utilisation. In contrast, organic micropollutants concentrated during anaerobic digestion and affected the quality of the digested sludge. Secondary sludge resulted less polluted and richer in nitrogen and phosphorus (up to three times) than primary sludge and is hence more suitable for agricultural use. Separate processing of primary and secondary sludge might therefore be an innovative option for sludge management that could maximise the possibilities of agricultural use of secondary sludge and limit disposal problems only to primary sludge. In fact, primary sludge could be easily treated and disposed of by conventional processes including thickening, anaerobic digestion, centrifugation and incineration, whereas the difficult digestibility of secondary sludge could be improved by disintegration pre-treatment before stabilisation.


Assuntos
Poluentes Ambientais/química , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Agricultura , Fertilizantes , Itália , Metais Pesados
16.
J Environ Manage ; 95 Suppl: S139-43, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20719427

RESUMO

This paper deals with the comparison of ultrasound (mechanical) and ozone (chemical) pre-treatment on the performances of excess sludge semi-continuous digestion. Sludge solubilisation has been investigated by varying specific energy input. For each pre-treatment, long anaerobic digestion tests were carried out by two parallel digesters: one reactor, as control unit, was fed with untreated waste activated sludge, and the other one was fed with disintegrated sludge. To evaluate and compare the efficacy of both pre-treatments, the specific energy was maintained approximately the same. The digestion tests were carried out to investigate the feasibility of anaerobic digestion performance (total biogas production, volatile solids removal, sludge dewaterability) and to assess the heat balance. Results obtained from the digestion of sonicated sludge at 4% disintegration degree (≈ 2500 kJ/kg TS) showed that the ultrasound pre-treatment may be effective both in increasing VS destruction (+19%) and cumulative biogas production (+26%). On the contrary, the digestion test with ozonized sludge (ozone dose of 0.05 g O(3)/g TS corresponding to ≈ 2000 kJ/kg TS) did not indicate a significant improvement on the digestion performances. By doubling the ozone dose an improvement in the organics removal and cumulative biogas production was observed. Relevant differences in terms of colloidal charge and filterability were discussed.


Assuntos
Ozônio , Esgotos , Ultrassom/métodos , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Biodegradação Ambiental , Biocombustíveis , Análise da Demanda Biológica de Oxigênio , Esgotos/química , Sonicação , Temperatura
17.
Bioresour Technol ; 102(16): 7567-73, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21641205

RESUMO

The objective of this work was to maximize the digestibility of biological sludge to elucidate the feasibility of a new sludge management strategy to recover good quality sludge for agricultural use. The combined effects of organic loading rates (from 0.7 to 2.8g VS L(-1)d(-1)) and the degree of disintegration by anaerobic digestion of sonicated activated sludge were discussed, and the thermal and energetic balances were evaluated. Despite low sonication inputs, sludge digestion performance improved in terms of solids degradation and biogas production depending on the soluble organic load. The biogas production by sonicated sludge was higher (up to 30%) with respect to the control. Filterability improved during digestion of sonicated sludge at medium OLR due to a significant abatement of the fines. Thermal balances indicated that sonication may be a proper system to guarantee self-sustaining WAS mesophilic digestion. Nevertheless, thickening is a pre-requisite to achieve a positive energy balance.


Assuntos
Temperatura Alta , Esgotos/química , Sonicação/métodos , Gerenciamento de Resíduos/métodos , Bactérias Anaeróbias/metabolismo , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos , Filtração
18.
J Chromatogr A ; 1217(27): 4601-11, 2010 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-20564801

RESUMO

Analysis of 11 polybrominated diphenyl ethers (PBDEs), tetrabromobisphenol A bis 2,3-dibromopropylether (TBBPA-bis), tetrachlorobisphenol A (TCBPA), tetrabromobisphenol A (TBBPA) and hexabromocyclododecanes (HBCDs) was optimized by ultrahigh pressure liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) operating in negative ion (NI) mode. Electrospray ionization (ESI), atmospheric pressure photoionization (APPI) and atmospheric pressure chemical ionization (APCI) sources were tested and for PBDEs APCI gave higher sensitivity than APPI while for TBBPA-bis APCI and APPI showed similar performance. ESI was the best option for TCBPA, TBBPA and HBCDs. Detection limits were between 20 and 59 fg for the compounds analyzed by ESI, 0.10 and 0.72 pg for PBDEs and 6 pg for TBBPA-bis. The matrix effect of sewage sludge extract was also tested showing negligible ion suppression for APCI and an increase of the background level of all investigated pollutants leading to a worsening of the limits of quantification by a factor between 1.2 and 3.3. The UPLC-APCI/MS/MS method for PBDEs, after pressurized liquid extraction (PLE), was validated by comparison with the concentration values from the NIST 1944 standard reference material. The advantages of the methods include low detection limits, PBDE congeners specificity using selected multiple reaction monitoring (MRM) transitions, and the absence of thermal degradation of higher PBDE congeners, especially BDE-209. The methods were applied for the determination of the above reported flame retardants in sewage sludge in order to get more information about the degradation on PBDEs (in particular BDE-209) during municipal wastewater treatments.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Hidrocarbonetos Bromados/análise , Esgotos/química , Espectrometria de Massas em Tandem/métodos , Sedimentos Geológicos/química , Sensibilidade e Especificidade
19.
Water Sci Technol ; 60(8): 2025-33, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19844049

RESUMO

The goal of this study was to follow and compare dewaterability parameters of untreated and "pre-sonicated" sludge during semicontinuous anaerobic digestion by particle charge density and sludge filterability measurements. Floc disintegration due to sonication resulted in a significant increase of soluble COD and colloidal charge density. It is interesting to note that in all the tests despite the higher specific charge density and soluble COD values of the sonicated feed, the digested sludge at steady state present in both reactors statistically comparable values, independently on the pretreatment. The biological hydrolysis of the untreated sludge causes a large release of dispersed charged fines whereas the digestion of the sonicated sludge is characterized by a significant removal of fines and colloids already present in the pretreated feed. The amelioration of the filterability during the digestion of the sonicated sludge in test #2 suggest that anaerobic digestion may be very effective for degrading fine dispersed particles produced by mechanical pre-hydrolysis. Nevertheless, ultrasound pre-treatment does not improve the dewaterability of the digested sludge with respect to the untreated one. Optimisation of both disintegration degree and hydraulic residence time is necessary to improve the dewaterability of the digested sonicated sludge.


Assuntos
Filtração , Esgotos/microbiologia , Eletricidade Estática , Ultrassom , Anaerobiose , Coloides/química , Oxigênio/isolamento & purificação , Eliminação de Resíduos , Solubilidade , Sonicação , Propriedades de Superfície
20.
Appl Psychophysiol Biofeedback ; 34(2): 105-11, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19308725

RESUMO

In this paper we examined the influence of repetition of weight-related sentences on the involuntary pressure forces of the forearms, when in a relaxed state. These forces were involuntary oscillations, exerted by muscle movements of the breathing-cycle and muscle movements of the arm on force sensors. We constructed a linguistic bio-mechanical system (Ablasmi), where in each arm of a padded relaxation chair contained special sensors that were specifically designed to detect the pressure forces of each forearm while participants listened to the specific recorded weight-related sentences. In this experiment we used some classic sentences, such as "your right/left arm is heavy," inspired by Autogenic Training (Schultz in Le training autogene. Paris, PUF, 1974) and some sentences, such as "your right/left arm is made of lead," inspired by Grossmann's relaxation technique. We observed that when the recorded sentences were directed to the right arm there was a significant increase of involuntary pressure forces on the right forearm. Additionally, we observed the same effect on the left forearm for the sentences directed to the left forearm. Thus, we believe we have provided experimental evidence of a definite linguistic effect of weight-related sentences on the involuntary pressure forces of the forearms. The implications of these findings are discussed.


Assuntos
Antebraço/fisiologia , Idioma , Terapia de Relaxamento , Relaxamento/fisiologia , Adulto , Braço/fisiologia , Dança/fisiologia , Eletromiografia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Pressão , Mecânica Respiratória , Adulto Jovem
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