Fast pyrolysis of halogenated plastics recovered from waste computers

The disposal of waste computers is an issue that is gaining increasing interest around the world. In this paper, results from the fast pyrolysis in a fluidized bed reactor of three different waste computer monitor casings composed of mainly acrylonitrile-butadiene-styrene (ABS) copolymer and two different waste computer body casings composed of mostly poly(vinyl chloride) (PVC) type polymers are presented. Preliminary characterization of the waste plastics was investigated using coupled thermogravimetric analysis-Fourier transform infrared spectrometry (TGA-FT-IR). The results showed that the plastics decomposed in two stages. For the ABS-containing monitor casings, aromatic and aliphatic material were released in the first and second stages. The PVC-containing computer body casing samples showed a first-stage evolution of HCl and a second stage evolution of aromatic and aliphatic material and further HCl. In addition, each of the five plastics was fast-pyrolyzed in a laboratory-scale fluidized bed reactor at 500 °C. The fluidized bed pyrolysis led to the conversion of most of the plastics to pyrolysis oil, although the two PVC computer body cases produced large quantities of HCl. The pyrolysis oils were characterized by GC-MS and it was found that they were chemically very heterogeneous and contained a wide range of aliphatic, aromatic, halogenated, oxygenated, and nitrogenated compounds

Is natural orifice specimen extraction surgery really safe in radical surgery for colorectal cancer?

Scop: Chirurgia rectală robotică este în prezent o procedură nouă pentru cancerele rectale. Extracția eșantionului cu orificiu natural transanal (NOSE) este o tehnică nouă de îndepărtare a specimenului din cavitatea abdominală prin anus, în loc de o incizie suplimentară după o intervenție chirurgicală colorectală laparoscopică sau robotică. Siguranța NOSE rămâne controversată. Acest studiu și-a propus să investigheze siguranța precoce a NOSE transanal în tratamentul cancerului de colon sigmoid și rectal superior din următoarele aspecte: caracteristici clinice și patologice, indicatori inflamatori și imunitari și complicații postoperatorii. Prezentare de caz: O femeie de 61 de ani, diagnosticată anterior cu cancer rectal, cu antecedente de 6 luni de hematochezie și alternanta diaree-constipatie. Diagnosticul de cancer rectal a fost pus pe baza biopsiei colonoscopice care a confirmat un nodul circumferenţial neregulat de adenocarcinom bine diferenţiat la 10 cm de marginea anală. Rezecția anterioară joasă asistata robotic, urmata de extracția specimenului transanal a fost efectuată după obținerea consimțământului informat. Procedura a fost efectuată cu succes și pacienta a avut o evolutie postoperatorie fără complicații. Diagnosticul patologic postoperator a evidențiat un adenocarcinom moderat diferențiat de 4x4x0,6 cm3 și margine circumferențiala libera. Concluzii: Rezectia de rect robotica plus extractia transanala a specimenului pentru cancerul rectal poate fi efectuata în siguranță și poate fi o abordare eficientă în contrast cu abordarea deschisă sau laparoscopică.Background: Robotic rectal surgery is currently a novel procedure for rectal cancers. Transanal natural orifice specimen extraction (NOSE) is a novel technique to remove the specimen from the abdominal cavity through the anus instead of an additional incision following laparoscopic or robotic colorectal surgery. The safety of NOSE remains controversial. This study aimed to investigate the early safety of transanal NOSE in the treatment of sigmoid colon and upper rectal cancer from the follow aspects: clinical and pathological characteristics, inflammatory and immune indicators and postoperative complications. Case presentation: A 61-year-old women, previously diagnosed with rectal cancer with came 6 months history of hematochezia and altered bowel habit. A diagnosis of rectal cancer was made in view of colonoscopic biopsy which confirmed an irregular circumferential lump of well differentiated adenocarcinoma at 10 cm from the anal verge. Robotic low anterior resection (LAR) plus transanal natural orifice specimen extraction (NOSE) was performed after obtaining informed consent. The procedure was performed successfully and the patient convalesced nicely without any complications. The postoperative pathological diagnosis revealed a 4x4x0.6 cm3 moderately differentiated adenocarcinoma and circumferential clearance. Conclusions: Robotic LAR plus transanal NOSE for rectal cancer can be performed safely and may be an effective approach in contrast to open or laparoscopic approach

The role of the frozen section examination in the diagnosis of the thyroid nodules

Universitatea de Medicină și Farmacie Victor Babeș Timișoara, România, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: Diagnosticul diferențial preoperator sau intraoperator între leziunile tiroidiene benigne și maligne este de o importanță majoră pentru decizia chirurgicală intraoperatorie. Acest studiu analizează corelația dintre rezultatul examenului extemporaneu și rezultatul examinării histopatologice la parafină în cazul nodulilor tiroidieni. Material si metode: Acesta a fost un studiu retrospectiv asupra a 330 de cazuri cu patologie tiroidiană, operate în cadrul Clinicii 2 de Chirurgie a Spitalului Clinic Județean de Urgență Timișoara din 2011 până în 2014, la care s-au efectuat atât examen extemporaneu intraoperator (EXT) cât și examen histopatologic la parafină în cadrul Departamentului de Anatomo-patologie al aceluiași spital. Rezultate: Din cele 330 de cazuri studiate, examenul EXT a stabilit diagnosticul în 244 (73,9%) cazuri și la 86 (26.1%) cazuri diagnosticul a fost incert, cu o sensibilitate de 93,33%, specificitate de 95,81%, în timp ce precizia a ajuns la 95,66%. Două sute douazeci și nouă (84,8%) au fost tumori benigne, iar 15 (27,3%) au fost tumori maligne. La examenul histopatologic, din 86 cazuri incerte 51 (59,3%) au fost benigne, 30 (34,8%) maligne și 5 (5,8%) au ramas neclare. Concluzii: Rezultatele noastre cu metoda EXT sunt echivalente cu cele disponibile în literatura de specialitate cu specificitate, sensibilitate si precizie foarte bune. În cazul în care investigațiile preoperatorii evidențiază noduli unilaterali, EXT a fost util pentru decizia intraoperatorie între lobectomie și tiroidectomie totală, evitând lobectomia inutilă sau reintervenția.Introduction: Preoperative or intraoperative differential diagnosis between benign and malignant thyroid lesions is of utmost importance for the surgical intraoperative decision. This study analyses the correlation between the frozen-section result and the result of the histopathologic paraffin examination in cases of thyroid nodules. Material and methods: This was a retrospective study upon 330 cases with thyroid pathology, operated on in the 2nd Surgical Clinic of the Clinical County Emergency Hospital of Timisoara from 2011 to 2014, that had both intraoperative frozen-section (FS) and postoperative paraffin histologic examination performed by the Pathology Department of the same hospital. Results: Of 330 cases studied, FS examination set the diagnosis in 244 (73.9%) cases and no diagnosis (uncertain) in 86 (26.1%), with a sensitivity of 93.33%, specificity of 95.81%, while accuracy reached 95.66%. Two hundred twenty-nine (84.8%) were benign tumors and 15(27.3%) were malignant tumors. At the histopathologic examination, from 86 uncertain cases 51 (59.3%) were benign, 30(34.8%) malignant and 5 (5.8%) remained unclear. Conclusions: Our results with FS method are equivalent to those available in the literature with very good specificity, sensitivity and accuracy. In cases in which the preoperative investigations show unilateral nodules, FS was still useful for the intraoperative decision between lobectomy and total thyroidectomy, avoiding inutile lobectomy or reoperation

Pyrolysis and combustion of municipal solid wastes:evaluation of synergistic effects using TGA-MS

A thermogravimetric methodology was developed to investigate and semi-quantify the extent of synergistic effects during pyrolysis and combustion of municipal solid waste (MSW). Results from TGA-MS were used to compare the pyrolysis and combustion characteristics of single municipal solid waste components (polyvinyl chloride (PVC), polypropylene (PP), polystyrene (PS), branches (BR), leaves (LV), grass (GR), packaging paper (PK), hygienic paper (HP) and cardboard (CB)) and a mixture (MX) of PP, BR and CB. Samples were heated under dynamic conditions at 20°C/min from 25°C to 1000°C with the continuous record of their main evolved fragments. Synergistic effects were evaluated by comparing experimental and calculated weight losses and relative areas of MS peaks. Pyrolysis of the mixture happened in two stages, with the release of H2, CH4, H2O, CO and CO2 between 200 and 415°C and the release of CH4, CxHy, CO and CO2 between 415 and 525°C. Negative synergistic effect in the 1st stage was attributed to the presence of PP where the release of hydrocarbons and CO2 from BR and CB was inhibited, whereas positive synergistic effects were observed during the 2nd degradation stage. In a second part of the study, synergistic effects were related to the dependency of the effective activation energy (Eα) versus the conversion (α). Higher Eαs were obtained for MX during its 1st stage of pyrolysis and lower Eαs for the 2nd stage when compared to the individual components. On the other hand, mostly positive synergistic effects were observed during the combustion of the same mixture, for which lower Eαs were recorded

The Use of Agricultural Residues, Wood Briquettes and Logs for Small-Scale Domestic Heating

Large amounts of agricultural residues are produced annually in the UK alone, which presents a significant biomass energy resource. It has limited availability in briquetted form in the UK but is widely used, particularly in Asia. The aim of this work is to assess the emission from briquetted agricultural residues to wood fuel, including commercial wood briquettes, when utilised in a 5 kW domestic heating stove. Other straw-type materials, sugarcane bagasse, Miscanthus, were also investigated. The combustion behaviour depended on the chemical and physical nature of the briquettes. Results indicate that fuel choice is an important consideration for emission reduction. Fuel-N directly correlates to emitted NOx and all the fuels studied had NOx emissions below the EU regulation limit. While agricultural residues can be relatively high in Cl and S, there is evidence of in-situ capture of HCl and SO2 by calcium salts in the fuel ash. Particulate emissions correlate with the volatile matter in the fuel, but also are influenced by the quality/durability of the briquette. The briquettes performed well compared to wood logs, and while there is a fuel-type influence on emissions, it is also clear that briquettes from optimised manufacture can be lower emitting than wood logs

Chitosan–Starch–Keratin composites: Improving thermo-mechanical and degradation properties through chemical modification

The lysozyme test shows an improved in the degradability rate, the weight loss of the films at 21 days is reduced from 73 % for chitosan-starch matrix up to 16 % for the composites with 5wt% of quill; but all films show a biodegradable character depending on keratin type and chemical modification. The outstanding properties related to the addition of treated keratin materials show that these natural composites are a remarkable alternative to potentiat-ing chitosan–starch films with sustainable featuresChitosan–starch polymers are reinforced with different keratin materials obtained from chicken feather. Keratin materials are treated with sodium hydroxide; the modified surfaces are rougher in comparison with untreated surfaces, observed by Scanning Electron Microscopy. The results obtained by Differential Scanning Calorimetry show an increase in the endothermic peak related to water evaporation of the films from 92 °C (matrix) up to 102–114 °C (reinforced composites). Glass transition temperature increases from 126 °C in the polymer matrix up to 170–200 °C for the composites. Additionally, the storage modulus in the composites is enhanced up to 1614 % for the composites with modified ground quill, 2522 % for composites with modified long fiber and 3206 % for the composites with modified short fiber. The lysozyme test shows an improved in the degradability rate, the weight loss of the films at 21 days is reduced from 73 % for chitosan-starch matrix up to 16 % for the composites with 5wt% of quill; but all films show a biodegradable character depending on keratin type and chemical modification. The outstanding properties related to the addition of treated keratin materials show that these natural composites are a remarkable alternative to potentiat-ing chitosan–starch films with sustainable featuresUniversidad Autónoma del Estado de México Tecnológico Nacional de México, Instituto Tecnológico de Querétaro Universidad Nacional Autónoma de México Tecnológico Nacional de México, Instituto Tecnológico de Celaya Universidad Autónoma de Cd. Juáre