Catalytic Pyrolysis of Municipal Solid Waste: Effects of Pyrolysis Parameters

Burning municipal solid waste (MSW) increases CO2, CH4, and SO2 emissions, leading to an increase in global warming, encouraging governments and researchers to search for alternatives. The pyrolysis process converts MSW to oil, gas, and char. This study investigated catalytic and noncatalytic pyrolysis of MSW to produce oil using MgO-based catalysts. The reaction temperature, catalyst loading, and catalyst support were evaluated. Magnesium oxide was supported on active carbon (AC) and Al2O3 to assess the role of support in MgO catalyst activity. The liquid yields varied from 30 to 54 wt% based on the experimental conditions. For the noncatalytic pyrolysis experiment, the highest liquid yield was 54 wt% at 500 °C. The results revealed that adding MgO, MgO/Al2O3, and MgO/AC declines the liquid yield and increases the gas yield. The catalysts exhibited significant deoxygenation activity, which enhances the quality of the pyrolysis oil and increases the heating value of the bio-oil. Of the catalysts that had high deoxygenation activity, MgO/AC had the highest relative yield. The loading of MgO/AC varied from 5 to 30 wt% of feed to the pyrolysis reactor. As the catalyst load increases, the liquid yield declines, while the gas and char yields increase. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Simulation of blended nonlinear hydrodynamics forces using radial basis function in uniform moving frame

This study focuses on the development of a blended technique in moving frame which encompasses nonlinearities and real time simulation of the vital early design parameters using combined exact nonlinear and quasi-nonlinear forcing terms. Generally, a full three-dimensional problem needs to be solved for the precise forward speed correction. However, in this paper the forward speed end corrections are calculated by converting the two dimensional velocity potential into a three dimensional mathematical function using radial basis function then partial differentiation is performed with respect to the longitudinal direction. The difference between the forward speed correction used for time simulation in the blended method and the strip-theory in the frequency domain has been explained. The use of radial basis functions for the estimation of quasi-nonlinear combined radiation and diffraction pressures in moving frame and their conversion between two and three dimensions has been demonstrated and validated experimentally

Predicting the effect of voids on mechanical properties of woven composites.

An accurate yet easy to use methodology for determining the effective mechanical properties of woven fabric reinforced composites is presented. The approach involves generating a representative unit cell geometry based on randomly selected 2D orthogonal slices from a 3D X-ray micro-tomographic scan. Thereafter, the finite element mesh is generated from this geometry. Analytical and statistical micromechanics equations are then used to calculate effective input material properties for the yarn and resin regions within the FE mesh. These analytical expressions account for the effect of resin volume fraction within the yarn (due to infiltration during curing) as well as the presence of voids within the composite. The unit cell model is then used to evaluate the effective properties of the composite.DelPHE 780 Project funded by UK Department of International Development (DFID), through British Council managed DelPHE scheme

Micromechanical modeling of 8-harness satin weave glass fiber-reinforced composites.

This study introduces a unit cell (UC) based finite element (FE) micromechanical model that accounts for correct post cure fabric geometry, in-situ material properties and void content within the composite to accurately predict the effective elastic orthotropic properties of 8-harness satin weave glass fiber reinforced phenolic (GFRP) composites. The micromechanical model utilizes a correct post cure internal architecture of weave, which was obtained through X-ray microtomography (XMT) tests. Moreover, it utilizes an analytical expression to up-date the input material properties to account for in-situ effects of resin distribution within yarn (the yarn volume fraction) and void content on yarn and matrix properties. This is generally not considered in modeling approaches available in literature and in particular, it has not been demonstrated before for FE micromechanics models of 8-harness satin weave composites. The UC method is used to obtain the effective responses by applying periodic boundary conditions. The outcome of the analysis based on the proposed model is validated through experiments. After validation, the micromechanical model was further utilized to predict the unknown effective properties of the same composite.DFID UK through DELPHE 78

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

Compressive behaviour of Neovius Triply Periodic Minimal Surface cellular structure manufactured by fused deposition modelling

Compressive behaviour of Triply Periodic Minimal Surface type Neovius structure is investigated. The structure was manufactured by Fused Deposition Modelling (FDM) Additive Manufacturing technology in ABS material. The Neovius cellular structures with four different unit cell sizes of 8, 10, 12 and 14 mm with the volume fractions of 15%, 20% and 25% were investigated. Morphology of the samples was analysed through optical microscopy, and the pore and strut sizes were compared for the designed model and FDM samples. During the compression test, the Neovius structure showed the oscillating behaviour of the stress–strain curve with the larger unit cell size showing fracture across multiple layers in different orientations. Optical analysis of the struts after the compression tests showed that struts are the weakest link with the highest stressed area and the fracture was seen initiated at the struts. Both compressive modulus and strength increased with the increase in volume fraction.

Effect of smoking on periodontal health and validation of self-reported smoking status with serum cotinine levels

Abstract Objectives: To investigate whether self-reported smoking and serum cotinine levels associate with periodontal pocket development and to determine the accuracy of self-reported smoking using serum cotinine. Materials and methods:This 4-year prospective cohort study included data from 294 dentate adults, aged ≥30 years, who participated in both the Health 2000 Survey and the Follow-up Study of Finnish Adults’ Oral Health. Subjectively reported smoking status (daily smokers n = 62, occasional smokers n = 12, quitters n = 49, and never-smokers n = 171), serum cotinine levels, demographic factors, education level, dental behaviours and medical history were collected at baseline. The outcome measure was the number of teeth with periodontal pocketing ≥4 mm over 4 years. Results:Self-reported daily smokers had 1.82 (95% CI: 1.32–2.50) higher incidence of deepened periodontal pockets than never-smokers. A positive association was observed between serum cotinine (≥42.0 μg/L) and the development of periodontal pockets. The misclassification rate of self-reported smoking was 6%. Conclusions:Both self-reported daily smoking and higher serum cotinine were associated with periodontal pocket development. Self-reported smoking was fairly accurate in this study. However, higher cotinine levels among a few self-reported never-smokers indicated misreporting or passive smoking. Thus, self-reports alone are not enough to assess the smoking-attributable disease burden

Biological management of selected weeds of wheat through co-application of allelopathic rhizobacteria and sorghum extract

Traditional methods of weeds management have caused serious environmental and health concerns. Therefore, development of alternate strategies for effective management of weeds is becoming indispensable for sustainable agriculture. In this study, the comparative effectiveness of chemical and bio-herbicides for the management of weeds in wheat has been assessed under laboratory and field conditions. Two effective allelopathic rhizobacteria (6 K and 6) were selected from initial screening experiment which had abilities to suppress the growth of selective weeds as well as had potential to improve the growth of wheat. Based on 16S ribosomal RNA (16S rRNA) gene sequencing, the selected allelopathic rhizobacteria were identified as Pseudomonas fluorescens strain 6 K and Bacillus sp. strain 6. Further, sorghum allelopathic water extract was also used in combination with selected allelopathic rhizobacteria as a bio-herbicide. Five treatments used for the laboratory and field experiments were control (T1: without herbicide), chemical herbicide (T2: mesosulfuron methyl + idosulfuron methyl; Atlantis® 6WG), sorghum allelopathic extract (T3), consortium of two different allelopathic rhizobacteria (T4) and combined application of allelopathic extract of sorghum and consortium of two allelopathic rhizobacteria (T5 = T3 + T4). Results of laboratory experiment showed that T5 significantly suppressed the seed germination percentage of four selected weeds i.e., Anagallis arvensis L., Phalaris minor Retz., Cynodon dactylon L. and Melilotus indicus L. and the same treatment (T5) also significantly improved seed germination of wheat as compared to all other treatments. Further evaluation under field condition showed that T5 significantly decreased the weed density and total weed biomass at 15, 30 and 45 days after sowing (DAS) of all weeds as compared to T1 (control). Field trial results also indicated that T5 significantly increased the wheat growth traits including the biological yield (73%) and grain yield (53%) as compared to T1. Likewise, the economic analysis revealed that T5 improved the net benefits with a higher marginal rate of return than all other treatments. Our findings indicated that combined application of allelopathic rhizobacterial consortium and allelopathic extract of sorghum remained more effective for controlling weeds and improving the growth and yield traits of wheat as compared to their sole application. Therefore, co-application of allelopathic rhizobacterial consortium and sorghum allelopathic water extract could offer an economically viable lever for the biological management of weeds of wheat for sustainable production