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1.
Membranes (Basel) ; 13(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37367782

RESUMO

The interest of the fusion community in Pd-Ag membranes has grown in the last decades due to the high value of hydrogen permeability and the possibility of continuous operation, making it a promising technology when a gaseous stream of hydrogen isotopes must be recovered and separated from other impurities. This is the case of the Tritium Conditioning System (TCS) of the European fusion power plant demonstrator, called DEMO. This paper presents an experimental and numerical activity aimed at (i) assessing the Pd-Ag permeator performance under TCS-relevant conditions, (ii) validating a numerical tool for scale-up purposes, and (iii) carrying out a preliminary design of a TCS based on Pd-Ag membranes. Experiments were performed by feeding the membrane with a He-H2 gas mixture in a specific feed flow rate ranging from 85.4 to 427.2 mol h-1 m-2. A satisfactory agreement between experiments and simulations was obtained over a wide range of compositions, showing a root mean squared relative error of 2.3%. The experiments also recognized the Pd-Ag permeator as a promising technology for the DEMO TCS under the identified conditions. The scale-up procedure ended with a preliminary sizing of the system, relying on multi-tube permeators with an overall number ranging between 150 and 80 membranes in lengths of 500 and 1000 mm each.

2.
Molecules ; 25(23)2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33271993

RESUMO

Non-evaporable getters (NEGs) are metallic compounds of the IV group, particularly titanium and/or zirconium-based alloys and are usually used as pumps in vacuum technologies since they are able to sorb, by chemical reactions, most of the active gas molecules, with particular efficacy towards hydrogen isotopes. This work suggests an alternative application of these materials to fusion nuclear reactors, where there is the need to recover small amount of tritium from the large helium flow rate composing the primary coolant loop. Starting from the tritium mass balance inside the primary coolant loop, the amount of coolant to be routed inside the coolant purification system (CPS) is identified. Then a feasibility study, based on the bulk getter theory, is presented by considering three different commercial alloys, named ST707, ST101 and ZAO. The results provide the mass, the area and the regeneration parameters of the three different alloys necessary to fulfill the requirements of the CPS unit. By comparing the features of the three alloys, the ZAO material appears the most promising for the proposed application because it requires the lower amount of material and a lower number of regeneration cycles.


Assuntos
Ligas/química , Titânio/química , Trítio/análise , Trítio/isolamento & purificação , Zircônio/química , Trítio/química
3.
Vet Ital ; 54(4): 323-332, 2018 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-30681131

RESUMO

Animal assisted interventions (AAI) have become increasingly popular in Western countries during the last fifty years, attracting a lot of attention both from the general public and the scientific community. In Italy, similarly to other countries, this evolution has been accompanied by the diffusion of associations delivering AAI. What is the current state of AAI in Italy? How many realities are dealing with AAI? What professionals and animals are involved? The results of the questionnaire here reported have the objective to answer these questions, outlining a snapshot of the distribution and the main features of AAI within Italian territory. According to the 208 respondents, the sector has seen a remarkable expansion over the last twenty years. AAI providers are located mainly in the North and Centre of the country, the majority of them are arranged in associations or AAI specialized centers and work mainly with dogs and equids in animal assisted activity (AAA) programs addressed to disabled people and children. The picture of the sector still appears fragmented in particular regarding team of professionals involved and their training; nonetheless, the recent set up of national guidelines by the Italian authorities has the objective of standardizing the field and defining best practices for each type of intervention.


Assuntos
Terapia Assistida com Animais/estatística & dados numéricos , Terapia Assistida com Animais/classificação , Animais , Humanos , Itália
4.
Vet Sci ; 4(3)2017 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-29056702

RESUMO

Equine assisted interventions (EAIs) are recently facing an increasing popularity, and are characterized by a wide diversity of practices. However, information on the welfare of animals involved in this kind of activity is often lacking. Horses are highly susceptible to work stressors related to physical constraints and/or to the need to control emotions while interacting with humans. Considerations of the emotional state of horses involved in EAIs have multiple valences: for the safety of humans and animals involved, for the quality and efficacy of interventions, as well as for ethical reasons. The aim of this unsystematic narrative review is to summarize the different approaches used for the evaluation of horses' stress responses, investigate their application in the context of EAIs, and discuss some methodological considerations for researchers and practitioners involved in EAI. The sources of information are mostly based on electronic databases (i.e., Medline, Scopus and Google scholar), as well as on hand searches of the references of retrieved literature, and discussions with experts in the field. At present, a few studies have investigated horses' stress responses during EAIs, and further studies are recommended, with the final aim to derive a reliable multidimensional method for assessing a horse's reaction during therapeutic programs, ultimately helping professionals to better develop interventions by taking into consideration the animal's perspective.

5.
Complement Ther Med ; 33: 20-26, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28735821

RESUMO

OBJECTIVES: The present study had a dual purpose: to obtain a comprehensive picture of the Italian medical practitioners' opinions, professional experiences, training needs and knowledge of Animal Assisted Interventions (AAI); and to provide a detailed description of the medical practitioners who are characterized by a strongly positive attitude towards AAI. METHODS: An online survey addressed to Italian medical practitioners was carried out using a 35-items structured questionnaire. Data obtained from the survey were analysed through appropriate summary statistics, analysis of variance (ANOVA) and logistic regression analysis. RESULTS: 670 medical practitioners participated in the online survey. Among them, 508 stated that they knew of AAI. 93.7% of these described themselves fully favourable towards the use of the human-animal relationship for therapeutic purposes, 84.4% defined themselves as confident and interested in studying the theme. A positive attitude towards AAI was greater in females, in people between 45 and 54 years old, in those who are pet owners and in those who believe that conferences are the most suitable tool to share information on AAI. CONCLUSIONS: The chance of having a positive attitude towards AAI is higher in respondents with specific characteristics. Data collected could be used as a starting point to promote and implement communication and training activities on AAI addressed to medical practitioners.


Assuntos
Terapia Assistida com Animais , Atitude do Pessoal de Saúde , Competência Clínica , Conhecimentos, Atitudes e Prática em Saúde , Médicos , Adulto , Fatores Etários , Idoso , Análise de Variância , Terapia Assistida com Animais/educação , Animais , Conscientização , Feminino , Necessidades e Demandas de Serviços de Saúde , Humanos , Itália , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Animais de Estimação , Autoeficácia , Fatores Sexuais , Inquéritos e Questionários
6.
Artigo em Inglês | MEDLINE | ID: mdl-28672787

RESUMO

Drug addiction is a major care and safety challenge in prison context. Nowadays, rehabilitation and specific therapeutic programs are suggested to improve health and well-being of inmates during their detention time and to reduce substance abuse relapse after release from prison. Among these programs, several studies reported the benefits for inmates coming from animal assisted interventions. In this pilot controlled study, we investigated the efficacy of a dog assisted therapy program addressed to 22 drug addicted male inmates housed in an attenuated custody institute in Italy. The study lasted six months, the treated group (12 inmates) was involved once a week for one hour in 20 dog assisted therapy sessions, whereas the control group (10 inmates) followed the standard rehabilitation program. One week before the beginning and one week after the end of the sessions, all inmates involved were submitted to symptom checklist-90-revised and Kennedy axis V. Inmates involved in the dog assisted therapy sessions significantly improved their social skills, reducing craving, anxiety and depression symptoms compared to the control group. Despite the limitation due to the small number of inmates enrolled and to the absence of follow up, we found these results encouraging to the use of dog assisted therapy as co-therapy in drug addicted inmates rehabilitation programs, and we claim the need of more extensive study on this subject.


Assuntos
Terapia Assistida com Animais/estatística & dados numéricos , Ansiedade/terapia , Fissura , Depressão/terapia , Usuários de Drogas/estatística & dados numéricos , Habilidades Sociais , Adulto , Animais , Cães , Humanos , Itália , Masculino , Projetos Piloto , Prisioneiros/estatística & dados numéricos , Adulto Jovem
7.
J Am Chem Soc ; 127(9): 3038-43, 2005 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-15740142

RESUMO

We have investigated the high-pressure properties of the molecular crystal para-diiodobenzene, by combining optical absorption, reflectance, and Raman experiments with Car-Parrinello simulations. The optical absorption edge exhibits a large red shift from 4 eV at ambient conditions to about 2 eV near 30 GPa. Reflectance measurements up to 80 GPa indicate a redistribution of oscillator strength toward the near-infrared. The calculations, which describe correctly the two known molecular crystal phases at ambient pressure, predict a nonmolecular metallic phase, stable at high pressure. This high-density phase is characterized by an extended three-dimensional network, in which chemically bound iodine atoms form layers connected by hydrocarbon bridges. Experimentally, Raman spectra of samples recovered after compression show vibrational modes of elemental solid iodine. This result points to a pressure-induced molecular dissociation process which leads to the formation of domains of iodine and disordered carbon.

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