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1.
Waste Manag ; 34(12): 2647-55, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25263216

RESUMO

Packaging is expected to become the leading application for nano-composites by 2020 due to the great advantages on mechanical and active properties achieved with these substances. As novel materials, and although there are some current applications in the market, there is still unknown areas under development. One key issue to be addressed is to know more about the implications of the nano-composite packaging materials once they become waste. The present study evaluates the extrusion process of four nanomaterials (Layered silicate modified nanoclay (Nanoclay1), Calcium Carbonate (CaCO3), Silver (Ag) and Zinc Oxide (ZnO) as part of different virgin polymer matrices of polyethylene (PE), Polypropylene (PP) and Polyethyleneterephtalate (PET). Thus, the following film plastic materials: (PE-Nanoclay1, PE-CaCO3, PP-Ag, PET-ZnO, PET-Ag, PET-Nanoclay1) have been processed considering different recycling scenarios. Results on recyclability show that for PE and PP, in general terms and except for some minor variations in yellowness index, tensile modulus, tensile strength and tear strength (PE with Nanoclay1, PP with Ag), the introduction of nanomaterial in the recycling streams for plastic films does not affect the final recycled plastic material in terms of mechanical properties and material quality compared to conventional recycled plastic. Regarding PET, results show that the increasing addition of nanomaterial into the recycled PET matrix (especially PET-Ag) could influence important properties of the recycled material, due to a slight degradation of the polymer, such as increasing pinholes, degradation fumes and elongation at break. Moreover, it should be noted that colour deviations were visible in most of the samples (PE, PP and PET) in levels higher than 0.3 units (limit perceivable by the human eye). The acceptance of these changes in the properties of recycled PE, PP and PET will depend on the specific applications considered (e.g. packaging applications are more strict in material quality that urban furniture or construction products).


Assuntos
Nanoestruturas/análise , Embalagem de Produtos , Reciclagem/métodos
2.
Artigo em Inglês | MEDLINE | ID: mdl-24328862

RESUMO

Two organo-modified clays for food contact applications were developed to produce hydrophobically modified montmorillonite and hence to obtain better compatibility between the biopolymer and the filler (nanoclay). These nanofillers were characterised by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction and thermogravimetric analysis (TGA) in order to study their composition, structure and thermal stability. The fillers were used to reinforce polylactic acid (PLA) bottles, which were characterised using different techniques such as mechanical and barrier properties, morphology and thermal stability. The results were compared with conventional PLA bottles. The use of the modified clay in PLA bottles was found to lead to an improvement in mechanical and barrier properties. Finally, cytotoxicity tests were carried out with the organo-modified clays using Caco-2 and HepG2 cell lines, with uptake of neutral red as a basal cytotoxicity biomarker.


Assuntos
Silicatos de Alumínio/química , Silicatos de Alumínio/toxicidade , Embalagem de Alimentos/métodos , Nanocompostos/química , Nanocompostos/toxicidade , Bentonita/química , Bentonita/toxicidade , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Argila , Células Hep G2 , Temperatura Alta , Humanos , Ácido Láctico/química , Ácido Láctico/toxicidade , Teste de Materiais , Microscopia Eletrônica de Transmissão , Nanocompostos/ultraestrutura , Permeabilidade , Poliésteres , Polímeros/química , Polímeros/toxicidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
3.
Acta Chir Belg ; 89(1): 58-60, 1989.
Artigo em Francês | MEDLINE | ID: mdl-2497613

RESUMO

The authors report the case of a patient who developed a Streptococcus Bovis septicemia in the post-operative course of a surgical cure of an incarcerated umbilical hernia. There were no other complaints. A barium enema showed a malignant tumor of the descending colon. There were hepatic metastases. No complementary treatment was undertaken. The patient died shortly after. In the literature colonic proliferative lesions in association with this germ is reported in a total of 36% of proliferative lesions (15% of cancers and 21% of adenomas). It is concluded that the discovery of a malignant or premalignant proliferative lesion in one third of the cases justifies the exploration of the colon by barium enema and/or colonoscopy in the case of Streptococcus Bovis septicemia. The discovery of other digestive lesions (malignant or not) seems to be coincidental.


Assuntos
Neoplasias do Colo/complicações , Hérnia Umbilical/cirurgia , Complicações Pós-Operatórias/etiologia , Sepse/etiologia , Infecções Estreptocócicas , Idoso , Neoplasias do Colo/diagnóstico , Enterococcus faecalis/isolamento & purificação , Feminino , Humanos , Sepse/microbiologia , Infecções Estreptocócicas/microbiologia
4.
Acta Chir Plast ; 31(3): 143-7, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2481919

RESUMO

A new method of restoration of the function of the upper limb in extensive posttraumatic defects of bones and soft tissues of the cubital joint has been elaborated. The method is based on the excision of scar tissues with simultaneous implantation of the endoprosthesis of the K. M. Sivash type. The produced defect is covered by a free vascularized thoracodorsal skin-muscle transplant using the microstructural technique. Four operations have been performed so far. Clinical observations are reported. The method is efficient as it ensures reliable covering of the hinge part of the endoprosthesis by full-thickness skin, shortening the time of rehabilitation treatment 3-4 times and achieving more complete restoration of the function of the upper limb.


Assuntos
Articulação do Cotovelo/cirurgia , Cotovelo/cirurgia , Prótese Articular , Microcirurgia/métodos , Transplante de Pele , Adulto , Articulação do Cotovelo/fisiopatologia , Humanos , Masculino , Lesões no Cotovelo
5.
Acta Chir Belg ; 86(5): 259-61, 1986.
Artigo em Francês | MEDLINE | ID: mdl-3788370

RESUMO

A short-term subcutaneous drainage has been established in twenty-five patients undergoing an inguinal hernia repair. In comparison with a control group, a significant decrease in the frequency of early appearance of inflammatory and hematic complications has been noted.


Assuntos
Drenagem , Hérnia Inguinal/cirurgia , Infecção da Ferida Cirúrgica/prevenção & controle , Idoso , Estudos de Avaliação como Assunto , Humanos , Masculino , Pessoa de Meia-Idade , Cicatrização
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