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1.
Waste Manag ; 186: 293-306, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38954921

RESUMO

The compositions of Dutch lightweight packaging waste (LWP) and sorted products named "PET (Polyethylene terephthalate) trays" have been determined on object level. Additionally, the PET trays from both waste types were sorted in 16 categories representing their packaging use and material build-up. The material composition of at least 10 representative trays from each category was determined with chemical and thermal analysis, based on which the average material composition per category was established. Based on this data the average material composition of sorted PET tray products was approximated. The recyclability of the various categories of PET trays was assessed based on their material build-up. The most ubiquitous PET trays in Dutch LWP and sorted products were only found to be suitable to produce opaque recycled PET with mechanical recycling processes. Whereas only some more uncommon PET trays can be used to produce transparent recycled PET with mechanical recycling processes. Depolymerisation is deemed to be a more appropriate recycling process that will allow the production of transparent food-grade recycled PET.


Assuntos
Polietilenotereftalatos , Embalagem de Produtos , Reciclagem , Reciclagem/métodos , Gerenciamento de Resíduos/métodos , Países Baixos , Resíduos , Eliminação de Resíduos/métodos
2.
Int J Biol Macromol ; 275(Pt 1): 133386, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38914407

RESUMO

Biodegradable starch foam trays offer an eco-friendly substitute for petroleum-based single-use packaging, notably polystyrene foams. However, they lack flexibility, tensile strength, and water-sensitivity, addressable through lignocellulosic reinforcement. This study aimed to develop biodegradable starch foam trays filled with different food-chain side streams for sustainable alternative packaging. Corncob, soybean straw, cassava peel, araucaria seed hull, yerba mate stalks and yerba mate leaves petiole were collected, dried and ground to <250 µm. The trays were filled with 13 % (w/w) of each food-chain side streams and produced by hot molding. The trays morphology, moisture, water activity (aw), thickness, bulk density, tensile strength, elongation at break, Young's modulus, bending strength, maximum deflection, and sorption isotherms were investigated. Reinforcements slightly increased the foams bulk density, reduced the tensile strength and maximum deflection and while bending strength increased from 0.20 MPa to 1.17-1.80 MPa. The elasticity modulus decreased by adding any filling, that resulted in ductility improvement; however, these packaging have moisture-sensitive material especially for aw higher than 0.52, which drives the use recommendation for dry products storage or shipping/transport. The biodegradable starch foam trays filled with side streams were successfully produced and offer excellent alternative to petroleum-based packaging low-density material with bending strength improved.

3.
Int J Biol Macromol ; 266(Pt 1): 131271, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38556239

RESUMO

Yerba mate industrial processing produces tons of powder as a by-product, this yerba mate powder (YMP) is an excellent source of biomass to develop biodegradable materials. Cassava starch modified with 1,2,3,4-butane tetracarboxylic acid (BA) in the presence of sodium propionate as a catalyst is an eco-friendly option to obtain bioadhesives. This work aimed to develop sustainable laminates from starch-based adhesives and yerba mate powder and to study their physico-chemical, structural, and mechanical properties. Blends of bioadhesive and YMP were prepared (1:1, adhesive:YMP). Monolayer materials were obtained by thermo-compression and later assembled with adhesive to obtain bilayer laminates. Bioadhesive was able to bind the yerba mate by-product fibers, as evidenced by SEM microstructure analysis, the interactions of adhesive:substrate were elucidated by ATR-FTIR and supported by chemometrics analysis. The incorporation of the catalyst decreased the rugosity of materials and their mechanical performance was improved by the action of both acid concentration and catalyst presence, requiring higher energy for puncture. Thus, it was feasible to obtain mono and bilayer laminates as an eco-compatible alternative for the design of sustainable tray-like materials based on the industrial by-product of yerba mate.


Assuntos
Adesivos , Manihot , Amido , Amido/química , Adesivos/química , Manihot/química
4.
Br J Anaesth ; 132(5): 911-917, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38336517

RESUMO

BACKGROUND: Anaesthetic drug administration is complex, and typical clinical environments can entail significant cognitive load. Colour-coded anaesthetic drug trays have shown promising results for error identification and reducing cognitive load. METHODS: We used experimental psychology methods to test the potential benefits of colour-coded compartmentalised trays compared with conventional trays in a simulated visual search task. Effects of cognitive load were also explored through an accompanying working memory-based task. We hypothesised that colour-coded compartmentalised trays would improve drug-detection error, reduce search time, and reduce cognitive load. This comprised a cognitive load memory task presented alongside a visual search task to detect drug errors. RESULTS: All 53 participants completed 36 trials, which were counterbalanced across the two tray types and 18 different vignettes. There were 16 error-present and 20 error-absent trials, with 18 trials presented for each preloaded tray type. Syringe errors were detected more often in the colour-coded trays than in the conventional trays (91% vs 83%, respectively; P=0.006). In signal detection analysis, colour-coded trays resulted in more sensitivity to the error signal (2.28 vs 1.50, respectively; P<0.001). Confidence in response accuracy correlated more strongly with task performance for the colour-coded tray condition, indicating improved metacognitive sensitivity to task performance (r=0.696 vs r=0.447). CONCLUSIONS: Colour coding and compartmentalisation enhanced visual search efficacy of drug trays. This is further evidence that introducing standardised colour-coded trays into operating theatres and procedural suites would add an additional layer of safety for anaesthetic procedures.


Assuntos
Anestésicos , Seringas , Humanos , Cor , Anestésicos/farmacologia , Erros de Medicação/prevenção & controle , Cognição
5.
Eur J Orthod ; 46(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37977877

RESUMO

BACKGROUND: The widespread use of CAD/CAM transfer trays warrants evaluation of their accuracy as compared to PVS transfer trays. OBJECTIVES: To quantify the accuracy of CAD/CAM and PVS transfer trays, investigating any differences between soft and hard trays CAD/CAM transfer trays. SEARCH METHODS: Eight different databases (Scopus, Web of Science, PubMed, Google Scholar, ProQuest, Embase, Cochrane Library, ClinicalTrials.gov) were searched, without restrictions, up to an end date of February 2023. SELECTION CRITERIA: Clinical trials (randomized and non-randomized) and in vitro studies reporting average imprecision values for bracket positioning obtained by digital superimpositions of digitally planned and real positions. DATA COLLECTION AND ANALYSIS: Data eligibility, data extraction, and risk of bias (RoB-2 and ROBINS-I) were conducted independently. The data, where possible, were synthesized and quantitatively analysed (meta-analysis of mean differences with 95% confidence intervals). The Grade of Recommendation, Assessment, Development and Evaluation (GRADE) analysis of the quality of evidence was performed. The t-test for independent samples was used to compare the transfer accuracy of hard and soft CAD/CAM transfer trays. RESULTS: Thirteen studies were synthesized in this systematic review, and then eight studies were included in the quantitative meta-analysis. As regards linear measurements, there was a mean transfer error of 0.0752 mm (95%CI: 0.0428, 0.1076) for mesiodistal measures, 0.0943 mm (95%CI: 0.0402, 0.1484) for vertical, and 0.0815 mm (95%CI: 0.0469, 0.1160) for buccolingual. As for angular measurements, there was an average transfer error of 1.2279° (95% CI: 0.6011, 1.8548) for inclination, 0.9397° (95%CI: 0.4672, 1.4123) for angulation, and 0.8721° (95%CI: 0.4257, 1.3185) for rotation. CAD/CAM transfer trays were less accurate than polyvinylsiloxane (PVS) transfer trays, with those made of soft material being more accurate than the hard ones, except for vertical dimension. The GRADE quality of evidence ranged from very low to moderate. CONCLUSIONS AND IMPLICATIONS: CAD/CAM transfer trays provide high bracket positioning accuracy, with soft transfer trays offering greater precision than rigid ones. Future randomized prospective trials are required to enhance the strength of the available evidence. REGISTRATION: Prospero (CRD42023401278 number).


Assuntos
Impressão Tridimensional , Estudos Prospectivos
6.
Dent Mater ; 39(9): 831-838, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37482433

RESUMO

OBJECTIVES: The present in vitro study aimed to evaluate the accuracy of three-dimensional (3D) printed indirect bonding trays consisting of hard or soft resin materials produced using computer-aided design and manufacturing (CAD/CAM). METHODS: Forty-eight dental casts were 3D printed. Four groups based on frontal crowding were defined and divided into hard- and soft-resin groups. After virtual bracket positioning on the digital models, the transfer trays were 3D printed. To evaluate the accuracy of the procedure, measurements were performed using a digital overlay of the virtual (target) bracket position and a post-bonding scan. The horizontal, transverse, and vertical deviations and angular discrepancies were analyzed. The loss rate was evaluated descriptively as a percentage. RESULTS: A total of 553 brackets were bonded using 24 soft and 24 resilient indirect bonding trays. The mean deviations were of 0.05 mm (transversal), 0.05 mm (horizontal), 0.09 mm (vertical), 0.13° (angulation) in the resilient resin group and of 0.01 mm (transversal), 0.08 mm (horizontal), 0.08 mm (vertical), 0.37° (angular) in the soft resin group. The loss rate was 6.9% and 0.7% in the hard and soft resin groups, respectively. Angular deviations were significantly higher in the soft resin group (P = 0.009), whereas the loss rate was considerably higher in the hard resin group (P < 0.001). SIGNIFICANCE: The findings indicate that indirect bonding using CAD/CAM is an accurate procedure in the laboratory setting. Soft resins are considered favorable for loss rate and useability.


Assuntos
Colagem Dentária , Braquetes Ortodônticos , Desenho Assistido por Computador , Colagem Dentária/métodos , Modelos Dentários , Projetos de Pesquisa , Método Simples-Cego
7.
Sci Total Environ ; 897: 165222, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37419361

RESUMO

Currently, the management of polyethylene terephthalate (PET) trays waste is still challenging since this packaging affects the consolidate recycling of PET bottles. It is important to separate PET trays from the PET bottle waste stream to avoid its contamination during recycling process and to recover a higher amount of PET. Hence, the present study aims to evaluate the environmental (by means of Life Cycle Assessment, LCA) and economic sustainability of sorting PET trays from the plastic waste streams selected by a Material Recovery Facility (MRF). For this scope, the case of a MRF in Molfetta (Southern Italy) was chosen as reference, and different scenarios have been evaluated by assuming different schemes of manual and/or automated PET trays sorting. The alternative scenarios did not achieve very pronounced environmental benefits over the reference case. Upgraded scenarios resulted in overall environmental impacts approx. 10 % lower as compared to the current scenario, with the exception of the climate and ozone depletion categories where differences in impacts were much higher. From an economic point of view, the upgraded scenarios achieved slightly lower costs (<2 %) than the current one. Electricity or labour costs were necessary in upgraded scenarios, but in this way fines for PET trays contamination in PET streams for recycling were avoided. Implementing any of the technology upgrade scenarios is then environmentally and economically viable, when the PET sorting scheme is performed in appropriate output streams through optical sorting.

8.
N Am Spine Soc J ; 14: 100208, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37124067

RESUMO

Background: Over-crowded surgical trays result in perioperative inefficiency and unnecessary costs. While methodologies to reduce the size of surgical trays have been described in the literature, they each have their own drawbacks. In this study, we compared three methods: (1) clinician review (CR), (2) mathematical programming (MP), and (3) a novel hybrid model (HM) based on surveys and cost analysis. While CR and MP are well documented, CR can yield suboptimal reductions and MP can be laborious and technically challenging. We hypothesized our easy-to-implement HM would result in a reduction of surgical instruments in both the laminectomy tray (LT) and basic neurosurgery tray (BNT) that is comparable to CR and MP. Methods: Three approaches were tested: CR, MP, and HM. We interviewed 5 neurosurgeons and 3 orthopedic surgeons, at our institution, who performed a total of 5437 spine cases, requiring the use of the LT and BNT over a 4-year (2017-2021) period. In CR, surgeons suggested which surgical instruments should be removed. MP was performed via the mathematical analysis of 25 observations of the use of a LT and BNT tray. The HM was performed via a structured survey of the surgeons' estimated instrument usage, followed by a cost-based inflection point analysis. Results: The CR, MP, and HM approaches resulted in a total instrument reduction of 41%, 35%, and 38%, respectively, corresponding to total cost savings per annum of $50,211.20, $46,348.80, and $44,417.60, respectively. Conclusions: While hospitals continue to examine perioperative services for potential inefficiencies, surgical inventory will be increasingly scrutinized. Despite MP being the most accurate methodology to do so, our results suggest that savings were similar across all three methods. CR and HM are significantly less laborious and thus are practical alternatives.

10.
Anaesth Intensive Care ; 51(2): 88-95, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36721955

RESUMO

Healthcare contributes to environmental harm. Trainee-led Research and Audit in Anaesthesia for Sustainable Healthcare (TRA2SH) is an Australasian network focused on sustainable anaesthesia practice. TRA2SH hypothesised that trainee-led audits alongside education presented on a scheduled national day, called Operation Clean Up, can improve engagement with sustainability initiatives. This paper aims to describe the first two years of Operation Clean Up in terms of goals, achievements and data collected so far. Environmental themes for Operation Clean Up were chosen based on available evidence (life cycle analyses and observational studies). The first Operation Clean Up (OCU 2020) focused on reducing the unnecessary use of single-use disposable absorbent pads (known as 'blueys' in Australia, 'greenies' in New Zealand). OCU 2021 included: refuse desflurane, reduce bluey use, reuse drug trays, and recycle paper and cardboard. TRA2SH provided an information pack to trainees who presented educational material to their department and fed back procurement figures to quantify each item. Descriptive statistics were used to analyse de-identified pooled data submitted to a centralised database.Eight departments submitted data for OCU 2020 and six provided follow-up data. Bluey use was reduced from a median of 37 to 34 blueys per ten surgical encounters. Fifteen departments submitted pre-campaign data for OCU 2021 with follow-up data to be collected during OCU 2022. Baseline data showed a median bluey use of 31 per ten surgical encounters. Volatile-related emissions were calculated; desflurane's proportion was 70% of these emissions yet was 11% of volatile procurement. Two participating departments removed desflurane from their formulary following OCU 2021. Operation Clean Up is a practical model for implementing sustainability initiatives using trainees as eco-leaders.


Assuntos
Anestesia , Anestesiologia , Humanos , Liderança , Desflurano , Austrália
11.
Front Bioeng Biotechnol ; 11: 1100155, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36741746

RESUMO

Additive manufacturing (AM) technologies can enable the direct fabrication of customized physical objects with complex shapes, based on computer-aided design models. This technology is changing the digital manufacturing industry and has become a subject of considerable interest in digital implant dentistry. Personalized dentistry implant treatments for individual patients can be achieved through Additive manufacturing. Herein, we review the applications of Additive manufacturing technologies in oral implantology, including implant surgery, and implant and restoration products, such as surgical guides for implantation, custom titanium meshes for bone augmentation, personalized or non-personalized dental implants, custom trays, implant casts, and implant-support frameworks, among others. In addition, this review also focuses on Additive manufacturing technologies commonly used in oral implantology. Stereolithography, digital light processing, and fused deposition modeling are often used to construct surgical guides and implant casts, whereas direct metal laser sintering, selective laser melting, and electron beam melting can be applied to fabricate dental implants, personalized titanium meshes, and denture frameworks. Moreover, it is sometimes required to combine Additive manufacturing technology with milling and other cutting and finishing techniques to ensure that the product is suitable for its final application.

12.
Br J Anaesth ; 130(3): 343-350, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36801016

RESUMO

BACKGROUND: Anaesthetic procedures are complex and subject to human error. Interventions to alleviate medication errors include organised syringe storage trays, but no standardised methods for drug storage have yet been widely implemented. METHODS: We used experimental psychology methods to explore the potential benefits of colour-coded compartmentalised trays compared with conventional trays in a visual search task. We hypothesised that colour-coded compartmentalised trays would reduce search time and improve error detection for both behavioural and eye-movement responses. We recruited 40 volunteers to identify syringe errors presented in pre-loaded trays for 16 trials in total: 12 error present and four error absent, with eight trials presented for each tray type. RESULTS: Errors were detected faster when presented in the colour-coded compartmentalised trays than in conventional trays (11.1 s vs 13.0 s, respectively; P=0.026). This finding was replicated for correct responses for error-absent trays (13.3 s vs 17.4 s, respectively; P=0.001) and in the verification time of error-absent trays (13.1 s vs 17.2 s, respectively; P=0.001). On error trials, eye-tracking measures revealed more fixations on the drug error for colour-coded compartmentalised trays (5.3 vs 4.3, respectively; P<0.001), whilst more fixations on the drug lists for conventional trays (8.3 vs 7.1, respectively; P=0.010). On error-absent trials, participants spent longer fixating on the conventional trials (7.2 s vs 5.6 s, respectively; P=0.002). CONCLUSIONS: Colour-coded compartmentalisation enhanced visual search efficacy of pre-loaded trays. Reduced fixations and fixation times for the loaded tray were shown for colour-coded compartmentalised trays, indicating a reduction in cognitive load. Overall, colour-coded compartmentalised trays were associated with significant performance improvements when compared with conventional trays.


Assuntos
Anestésicos , Seringas , Humanos , Cor , Erros de Medicação/prevenção & controle , Cognição
13.
Materials (Basel) ; 16(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36614752

RESUMO

Trays in which fruit and vegetables are transported over vast distances are not only stored in extreme climatic conditions but are also subjected to long-term loads. Therefore, it is very important to design them correctly and select the optimal raw material for their production. Geometric parameters that define the shape of the packaging may also be optimized in the design process. In this work, in order to select the most important parameters that affect the load capacity of a tray, sensitivity analysis was used. A sensitivity analysis is often the first step in the process of building artificial-intelligence-based surrogates. In the present work, using the example of a specific tray's geometry, the selection of starting parameters was carried out in the first step, based on the Latin hypercube sampling method. In the next step, local sensitivity analyses were performed at twenty selected starting points of the seventeen-dimensional space of the selected parameters. Based on the obtained results, it was possible to select the parameters that have a significant impact on the load capacity of the tray in the box compression test and whose influence is negligible or insignificant.

14.
Polymers (Basel) ; 14(13)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35808571

RESUMO

Poly(3-hydroxybutyrate-co-3-valerate) (PHBV), being one of the most studied and commercially available polyhydroxyalkanoates (PHAs), presents an intrinsic brittleness and narrow processing window that currently hinders its use in several plastic applications. The aim of this study was to develop a biodegradable PHA-based blend by combining PHBV with poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), another copolyester of the PHA family that shows a more ductile behavior. Blends of PHBV with 20% wt., 30% wt., and 40% wt. of PHBH were obtained by melt mixing, processed by cast extrusion in the form of films, and characterized in terms of their morphology, crystallization behavior, thermal stability, mechanical properties, and thermoformability. Full miscibility of both biopolymers was observed in the amorphous phase due to the presence of a single delta peak, ranging from 4.5 °C to 13.7 °C. Moreover, the incorporation of PHBH hindered the crystallization process of PHBV by decreasing the spherulite growth rate from 1.0 µm/min to 0.3 µm/min. However, for the entire composition range studied, the high brittleness of the resulting materials remained since the presence of PHBH did not prevent the PHBV crystalline phase from governing the mechanical behavior of the blend. Interestingly, the addition of PHBH greatly improved the thermoformability by widening the processing window of PHBV by 7 s, as a result of the increase in the melt strength of the blends even for the lowest PHBH content.

15.
Environ Sci Pollut Res Int ; 29(55): 83756-83769, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35771319

RESUMO

The low energy efficiency of the solar distillers is one of the key barriers to their effectual usage in the desalination domain. Hence, this work introduces an experimental investigation to enhance the freshwater productivity of the hemispherical solar distiller with different trays' configurations and utilizing wick materials. This was achieved by utilizing iron trays and wicks in the circular basin of hemispherical solar still in order to increase the vaporization surface area for better heat transfer of saline water. The performance of the hemispherical solar distiller was investigated with flat and v-corrugated iron trays configurations. Three distillers were designed and examined, namely, conventional hemispherical solar distiller, hemispherical solar distillery with flat iron trays, and hemispherical solar distiller with v-corrugated iron trays. Moreover, the combined effects of using wick materials with flat and v-corrugated iron trays in the basin of hemispherical distiller have been also investigated. Experiments were carried out at the desert climate conditions of El-Oued (33°27'N, 7°11'E), Algeria. The results showed that the productivity improvement is 42.85% and 14.30% over the conventional hemispherical distiller for v-corrugated and flat trays hemispherical solar still (HSD), respectively. While the inclusion of wick materials with v-corrugated iron trays further increases the productivity by about 83.12% over the reference distiller. Moreover, the energy efficiency of the flat trays HSD, v-corrugated trays HSD, HSD flat trays and wicks, and HSD v-corrugated trays and wicks is 38.72%, 48.28%, 52.16%, and 61.67%, respectively. Additionally, the .cost of freshwater production of HSD v-corrugated trays and wicks was 41.72% lower than that of a traditional hemispherical distiller.


Assuntos
Água Doce , Luz Solar , Águas Salinas , Temperatura Alta , Ferro
16.
Data Brief ; 41: 108001, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35282173

RESUMO

A material flow analysis of the main plastic types used and arising as waste in Switzerland in 2017 is conducted, including consideration of stock change. Seven main plastic application segments are distinguished (packaging; building and construction; automotive; electrical and electronic equipment; agriculture; household items, furniture, leisure and others; and textiles), further divided into 54 product subsegments. For each segment, the most commonly used plastic types are considered, in total including eleven plastic types (HDPE, LDPE, PP, PET, PS, PVC, ABS, HIPS, PA, PC, and PUR). All product life cycle stages are regarded, including the determination of the product subsegments in which the individual post-consumer secondary materials obtained from mechanical recycling are applied. The underlying data are gathered from official statistics and administrative databases, scientific literature, reports by industry organizations and research institutions, websites, and personal communication with stakeholders. The compiled data are then reconciled. All flow data are provided and depicted in two Sankey diagrams: one diagram shows the material flows on a product-subsegment level and the second one on a plastic-type level. Users may retrieve the data with a script and transfer them into a relational database. The present material flow analysis data are used as a basis for the scenario analysis in Klotz et al. [1]. Besides scenario modelling, the data can be used in conducting life cycle assessments. Both utilizations can serve as a support for designing future plastic flow systems.

17.
Food Chem ; 383: 132425, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35182876

RESUMO

In this study, active biopolymer trays, being part of the biodegradable packaging, were developed and characterised. The aim of our research was to determine how active packaging (trays + films) affects the quality of salmon storage. The trays had high antioxidant potential and were biodegradable, however, they limited germination and seed growth, which may have been caused by the low pH of the material. Furthermore, the applied packaging demonstrated a potential possible inhibitory effect on the accumulation of biogenic amines and the growth of microorganisms responsible for the spoilage of salmon fillets. Compared to the control group, fillets stored in the tested pack had a 19% lower total bacteria count on the 6th day of storage. The innovative packing is easily biodegradable and prolongs the shelf-life of salmon fillets, therefore, it shows promise as a packaging material for perishable food products.


Assuntos
Embalagem de Alimentos , Salmão , Alginatos , Animais , Conservação de Alimentos , Expectativa de Vida , Gomas Vegetais , Salmão/microbiologia , Chá
18.
Environ Sci Pollut Res Int ; 29(25): 38248-38257, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35076837

RESUMO

The present comprehensive study aims to achieve the highest freshwater productivity of hemispherical solar distillers which are characterized by having a large condensing and receiving surface area. This was done by incorporating two effective modifications to the design of the hemispherical solar distiller, namely the use of metal trays with high thermal conductivity and reflective mirrors. In the present experimental work, three different high thermal conductivity metal trays (steel, zinc, and copper) incorporated with the reflective mirrors were tested under the same climate conditions, in order to determine the optimum selection of metal trays that are incorporated with the reflective mirrors that achieve the highest performance of the hemispherical distillers. To realize this objective, four distillers were fabricated and tested at the same climate condition namely: Hemispherical solar Distiller with Black Silicone Walls (HSD-BSW) which represent the reference case, Hemispherical Solar Distiller with Steel Trays and Reflective Mirrors (HSD-ST&RM), Hemispherical Solar Distiller with Zinc Trays and Reflective Mirrors (HSD-ZT&RM), and Hemispherical Solar Distiller with Copper Trays and Reflective Mirrors (HSD-CT&RM). The experimental results presented that the utilization of copper trays incorporated with reflective mirrors (HSD-CT&RM) represents the very effective option to achieve the highest performance of the hemispherical solar distillers. The cumulative production achieve by the reference HSD-BSW reached 4.65 l/m2day, while utilization of copper trays incorporated with reflective mirrors (HSD-CT&RM) increases the cumulative production to 9.5 l/m2day, with an improvement of 104.3%. Also, utilization of copper trays incorporated with reflective mirrors (HSD-CT&RM) improves the daily thermal and exergy efficiencies by 102.4% and 194.9%, respectively compared to HSD-BSW. Additionally, the economic feasibility showed that the use of copper trays incorporated with reflective mirrors (HSD-CT&RM) is a very effective option as it reduces the cost of distilled water by 44.1%.


Assuntos
Cobre , Água Potável , Silicones , Aço , Condutividade Térmica , Zinco
19.
Cureus ; 13(11): e19866, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34963866

RESUMO

Background This study aimed to rationalize the surgical instrument trays (SITs) used in some trauma and orthopedic (T&O) procedures to reduce unnecessary costs. Methods SITs for several T&O procedures at our trust were assessed to judge the utility of each instrument. SITs for hip, knee, and shoulder arthroscopy, dynamic hip screw (DHS), rotator cuff repair, shoulder stabilization, total shoulder arthroplasty (TSR), and proximal humerus fracture fixation were reviewed. Infrequently used and irrelevant instruments were removed to minimize the number of used trays for each procedure. A qualitative survey was conducted following SIT rationalization to assess the practicality and suitability of these changes. Results The number of SITs was rationalized from four to two for DHS, three to one for hip, knee, and shoulder arthroscopy, five to two for rotator cuff repair and shoulder stabilization, three to one for TSR, and proximal humerus fracture fixation. Based on the local database figures for these procedures, the estimated number of used trays reduced from 2,785 to 1.015 (36.4%) trays per year. Based on the sterilization cost of £35 per tray, annual savings amounted to about £61,950. Qualitative analysis of theatre staff feedback showed increased time efficiency and a positive feeling of practicality. Conclusion The critical appraisal of the departmental operating practice is an effective tool to achieve cost-efficient practice. The rationalization of SITs for orthopedic procedures can result in significant savings by reducing sterilization costs alone.

20.
Waste Manag ; 135: 360-371, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34600294

RESUMO

Increasing material circularity is high on the agenda of the European Union in order to decouple environmental impacts and economic growth. While life cycle assessment (LCA) is useful for quantifying the associated environmental impacts, consistent LCA modeling of the large-scale changes arising from policy targets addressing material circularity (i.e., recycled content and recycling rate) is challenging. In response to this, we propose an assessment framework addressing key steps in LCA, namely, goal definition, functional unit, baseline versus alternative scenario definition, and modeling of system responses. Regulatory and economic aspects (e.g., trends in consumption patterns, market responses, market saturation, and legislative side-policies affecting waste management) are emphasized as critical for the identification of potential system responses and for supporting regulatory interventions required to reach the intended environmental benefits. The framework is recommended for LCA studies focusing on system-wide consequences where allocation between product life cycles is not relevant; however, the framework can be adapted to include allocation. The application of the framework was illustrated by an example of implementing a policy target for 2025 of 70% recycled content in PET trays in EU27+1. It was demonstrated that neglecting large-scale market responses and saturation lead to an overestimation of the environmental benefits from the policy target and that supplementary initiatives are required to achieve the full benefits at system level.


Assuntos
Reciclagem , Gerenciamento de Resíduos , Meio Ambiente
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