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1.
Waste Manag ; 128: 73-82, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33971379

RESUMO

In this work, a novel method to valorize the polymeric matrix of residual carbon fiber reinforced polymers (CFRP) in the recycling process of carbon fibers by pyrolysis is presented. The experiments have been carried out with an expired epoxy-based pre-preg and in a lab-scale installation composed of two reactors. In the first one, pyrolysis and oxidation have been carried out, while in the second one, the gases and vapors resulting from the thermal decomposition of the polymeric resin have been thermally treated. The following operating parameters have been studied in the pyrolysis step: dwell time, the use of N2 (N2 flow, no N2 flow and not even to inert the reaction medium) and the solid bed material of the second reactor. In the oxidation step, temperature and time have been optimized by using the theory of experiments based on 2 k factorial design was used. It has been demonstrated that clean carbon fibers and a gaseous fraction with 75% by volume of H2 can be obtained. This is possible through a combined process of (1) CFRP thermal decomposition at 500 °C, (2) thermal treatment of gases and vapors at 900 °C in a solid bed tubular reactor filled with a waste refractory material and (3) oxidation of pyrolysis solid at 500 °C during 165 min in presence of 1.3 L air min-1.


Assuntos
Polímeros , Pirólise , Fibra de Carbono , Gases , Hidrogênio , Reciclagem
2.
Waste Manag ; 57: 226-234, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26783101

RESUMO

The possibilities and limits of pyrolysis as a means of recycling plastic rich fractions derived from discarded phones have been studied. Two plastic rich samples (⩾80wt% plastics) derived from landline and mobile phones provided by a Spanish recycling company, have been pyrolysed under N2 in a 3.5dm3 reactor at 500°C for 30min. The landline and mobile phones yielded 58 and 54.5wt% liquids, 16.7 and 12.6wt% gases and 28.3 and 32.4wt% solids respectively. The liquids were a complex mixture of organic products containing valuable chemicals (toluene, styrene, ethyl-benzene, etc.) and with high HHVs (34-38MJkg-1). The solids were composed of metals (mainly Cu, Zn, and Al) and char (≈50wt%). The gases consisted mainly of hydrocarbons and some CO, CO2 and H2. The halogens (Cl, Br) of the original samples were mainly distributed between the gases and solids. The metals and char can be easily separated and the formers may be recycled, but the uses of the char will be restricted due to its Cl/Br content. The gases may provide the energy requirements of the processing plant, but HBr and HCl must be firstly eliminated. The liquids could have a potential use as energy or chemicals source, but the practical implementation of these applications will be no exempt of great problems that may become insurmountable (difficulty of economically recovering pure chemicals, contamination by volatile metals, etc.).


Assuntos
Telefone Celular , Resíduo Eletrônico , Plásticos , Reciclagem/métodos , Bromo , Cloro , Gases , Mercúrio
3.
Eur J Gynaecol Oncol ; 13(1 Suppl): 97-8, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1511723

RESUMO

Regional surgery can be defined as "the maximum cytoreduction of all macroscopic tumors developing in the abdominal cavity". The Authors present their experiences with this difficult technique and conclude that regional surgery can improve prognosis.


Assuntos
Neoplasias Intestinais/cirurgia , Neoplasias Ovarianas/cirurgia , Neoplasias Peritoneais/cirurgia , Feminino , Humanos , Neoplasias Intestinais/secundário , Excisão de Linfonodo , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/secundário , Análise de Sobrevida
4.
Minerva Chir ; 44(5): 855-9, 1989 Mar 15.
Artigo em Italiano | MEDLINE | ID: mdl-2725914

RESUMO

Various techniques are used for the anatomo-functional study of bilio-digestive anastomoses on jejunal loop autonomized according to Roux. Here a transparietojejunal endoscopic investigation is proposed that permits direct sight of the anastomosis, biliary sampling for cultural examination and dilatative type therapeutic manoeuvres, biopsies or extractions of residual stones from the bile ways that would not otherwise be possible without further surgery. A clinical case is reported.


Assuntos
Anastomose em-Y de Roux/métodos , Coledocostomia/métodos , Ducto Colédoco/cirurgia , Jejuno/cirurgia , Adulto , Colangiografia , Endoscopia , Feminino , Humanos
5.
Waste Manag ; 33(1): 52-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23098814

RESUMO

In this paper rejected streams coming from a waste packaging material recovery facility have been characterized and separated into families of products of similar nature in order to determine the influence of different types of ingredients in the products obtained in the pyrolysis process. The pyrolysis experiments have been carried out in a non-stirred batch 3.5 dm(3) reactor, swept with 1 L min(-1) N(2), at 500°C for 30 min. Pyrolysis liquids are composed of an organic phase and an aqueous phase. The aqueous phase is greater as higher is the cellulosic material content in the sample. The organic phase contains valuable chemicals as styrene, ethylbenzene and toluene, and has high heating value (HHV) (33-40 MJ kg(-1)). Therefore they could be used as alternative fuels for heat and power generation and as a source of valuable chemicals. Pyrolysis gases are mainly composed of hydrocarbons but contain high amounts of CO and CO(2); their HHV is in the range of 18-46 MJ kg(-1). The amount of COCO(2) increases, and consequently HHV decreases as higher is the cellulosic content of the waste. Pyrolysis solids are mainly composed of inorganics and char formed in the process. The cellulosic materials lower the quality of the pyrolysis liquids and gases, and increase the production of char.


Assuntos
Temperatura Alta , Embalagem de Produtos , Reciclagem , Catálise , Gases/análise , Alcatrões/análise
6.
Waste Manag ; 32(5): 826-32, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21795037

RESUMO

Pyrolysis may be an alternative for the reclamation of rejected streams of waste from sorting plants where packing and packaging plastic waste is separated and classified. These rejected streams consist of many different materials (e.g., polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polyethylene terephthalate (PET), acrylonitrile butadiene styrene (ABS), aluminum, tetra-brik, and film) for which an attempt at complete separation is not technically possible or economically viable, and they are typically sent to landfills or incinerators. For this study, a simulated plastic mixture and a real waste sample from a sorting plant were pyrolyzed using a non-stirred semi-batch reactor. Red mud, a byproduct of the aluminum industry, was used as a catalyst. Despite the fact that the samples had a similar volume of material, there were noteworthy differences in the pyrolysis yields. The real waste sample resulted, after pyrolysis, in higher gas and solid yields and consequently produced less liquid. There were also significant differences noted in the compositions of the compared pyrolysis products.


Assuntos
Plásticos , Embalagem de Produtos , Eliminação de Resíduos/métodos , Gerenciamento de Resíduos/métodos , Gases , Temperatura Alta , Plásticos/química , Polietilenotereftalatos/química , Polietilenos/química , Polipropilenos/química , Poliestirenos/química , Cloreto de Polivinila/química
7.
J Allergy (Cairo) ; 2011: 752098, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21274348

RESUMO

Rivastigmine is a cholinesterase inhibitor which improves cognitive function and is currently being used in patients with mild to moderate Parkinson's and Alzheimer's dementia. This drug can be given orally or topically, as transdermal patch. The latter form is currently used for most excellent compliance and few side effects. The most common cutaneous side effects are irritative dermatitis. We report the second case of active sensitization by the rivastigmine-patch in a patient suffering from Alzheimer's dementia.

8.
Waste Manag ; 31(8): 1852-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21530221

RESUMO

In this work, a study of the regeneration and reuse of ZSM-5 zeolite in the pyrolysis of a plastic mixture has been carried out in a semi-batch reactor at 440°C. The results have been compared with those obtained with fresh-catalyst and in non-catalytic experiments with the same conditions. The use of fresh catalyst produces a significant change in both the pyrolysis yields and the properties of the liquids and gases obtained. Gases more rich in C3-C4 and H(2) are produced, as well as lower quantities of aromatic liquids if compared with those obtained in thermal decomposition. The authors have proved that after one pyrolysis experiment the zeolite loses quite a lot of its activity, which is reflected in both the yields and the products quality; however, this deactivation was found to be reversible since after regeneration heating at 550°C in oxygen atmosphere, this catalyst recovered its initial activity, generating similar products and in equivalent proportions as those obtained with fresh catalyst.


Assuntos
Plásticos/química , Gerenciamento de Resíduos/métodos , Zeolitas/química , Catálise , Reciclagem/métodos
9.
Waste Manag ; 31(9-10): 1973-83, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21689920

RESUMO

In this work, the results obtained in catalytic pyrolysis of three plastic waste streams which are the rejects of an industrial packing wastes sorting plant are presented. The samples have been pyrolysed in a 3.5 dm(3) reactor under semi-batch conditions at 440 °C for 30 min in nitrogen atmosphere. Commercial ZSM-5 zeolite has been used as catalyst in liquid phase contact. In every case, high HHV gases and liquids which can be useful as fuels or source of chemicals are obtained. A solid fraction composed of the inorganic material contained in the raw materials and some char formed in the pyrolysis process is also obtained. The zeolite has shown to be very effective to produce liquids with great aromatics content and C3-C4 fraction rich gases, even though the raw material was mainly composed of polyolefins. The characteristics of the pyrolysis products as well as the effect of the catalyst vary depending on the composition of the raw material. When paper rich samples are pyrolysed, ZSM-5 zeolite increases water production and reduces CO and CO(2) generation. If stepwise pyrolysis is applied to such sample, the aqueous liquid phase can be separated from the organic liquid fraction in a first low temperature step.


Assuntos
Temperatura Alta , Plásticos/química , Gerenciamento de Resíduos/métodos , Catálise , Cloro/química , Gases/análise , Termogravimetria , Resíduos/análise , Água
10.
Waste Manag ; 30(4): 620-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19926462

RESUMO

The objective of this work is the study of pyrolysis as a feedstock recycling process, for valorizing the rejected streams that come from industrial plants, where packing and packaging wastes are classified and separated for their subsequent mechanical recycling. Four real samples collected from an industrial plant at four different times of the year, have been pyrolysed under nitrogen in a 3.5dm(3) autoclave at 500 degrees C for 30min. Pyrolysis liquids are a complex mixture of organic compounds containing valuable chemicals as styrene, ethyl-benzene, toluene, etc. Pyrolysis solids are composed of the inorganic material contained in the raw materials, as well as of some char formed in the pyrolysis process, and pyrolysis gases are mainly composed of hydrocarbons together with some CO and CO(2), and have very high gross calorific values (GCV). It has been proved by the authors that the composition of the raw material (paper, film, and metals contents) plays a significant role in the characteristics of pyrolysis products. High paper content yields water in the pyrolysis liquids, and CO and CO(2) in the gases, high PE film content gives rise to high viscosity liquids, and high metals content yields more aromatics in the liquid products, which may be attributed to the metals catalytic effect.


Assuntos
Fontes Geradoras de Energia , Temperatura Alta , Incineração , Resíduos Industriais , Plásticos/química , Dióxido de Carbono/análise , Monóxido de Carbono/análise , Catálise , Cidades , Conservação dos Recursos Naturais , Gases/análise , Resíduos Industriais/análise , Metais/análise , Metais/química , Papel
15.
Ann Ostet Ginecol Med Perinat ; 100(1): 47-54, 1979.
Artigo em Italiano | MEDLINE | ID: mdl-426439

RESUMO

PIP: A vast literature reports on the ability of some tumor tissues to preserve the receptorial system of the original cells, which can be an indication of hormonal dependence of tumors. The authors tried to determine in quantitative term the receptorial capacity of beta Estradiol 17 of the normal and of the pathological endometrium. 23 postmenopausal patients were investigated, 10 with adenocarcinoma of the uterus, 6 with uterine fibroleiomioma, 4 with genital prolapse, and 3 with recurrent metrorrhagia. The maximal receptorial concentration was found in the 10 patients with adenocarcinoma, with concentrations going from 39.8 to 86.3 femtomoli/mg proteins. The normal value of a normal endometrium would be from 22 to 60.2 femtomoli/mg proteins. Some hypotheses are advanced about the receptorial capacity of the pathological tissues studied.^ieng


Assuntos
Estradiol/metabolismo , Receptores de Estrogênio/metabolismo , Neoplasias Uterinas/metabolismo , Útero/metabolismo , Idoso , Feminino , Humanos , Pessoa de Meia-Idade
16.
Minerva Anestesiol ; 46(2): 301-4, 1980 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-7454004

RESUMO

The effects of Althesin (group A) and thiopentone (group B) in mother and newborn were compared after their use in the induction of narcosis in 80 patients undergoing Caesarean section. The mean doses of Althesin (0.072 ml/kg i.v.) and thiopentone (4.1 mg/kg i.v.) proved sufficient to guarantee rapid onset of sleep (about 20 seconds) in both groups. As of cardiovascular effects on the mother in the induction-extraction period, greater stability of cardiac frequency (c.f.) was noted with thiopentone, while Althesin produced rapid, frequent variations in c.f. The reverse phenomenon was observed with respect to arterial pressure variations. The clinical condition of the newborns at 1st, 3rd and 5th minutes after extraction, assessed by means of the Apgar index, was excellent in both groups of patients. Results obtained were assessed by analysing variance with the Fisher test.


Assuntos
Mistura de Alfaxalona Alfadolona , Anestesia Intravenosa/métodos , Anestesia Obstétrica/métodos , Cesárea , Adolescente , Adulto , Mistura de Alfaxalona Alfadolona/efeitos adversos , Índice de Apgar , Avaliação de Medicamentos , Feminino , Humanos , Recém-Nascido , Medicação Pré-Anestésica , Gravidez
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