Assessment of the Reaction Time on the Morphology and Quality of Carbon Nanotubes – Silica Microparticles

AbstractCarbon nanotube has been grafted in-situ on the surface of spherical silica gel via floating-catalyst chemical vapour deposition method. The reaction temperature was set to be 760°C and 5wt. % of ferrocene catalyst (dissolved in toluene) injected into the furnace at a rate of 0.04ml/min. The reaction time was varied from 1 hour to 8hours, with one hour interval. It was found that the reaction time of 3hours yields the best quality hybrid particles. Prolonging the reaction time more than 3hours resulted in the formation of CNT that consists of thicker tubes, based on the observation via Field Emission Scanning Electron Microscope (FESEM) and Transmission Electron Microscope (TEM). Secondary overgrowth was observed via TEM for tubes synthesized at 7hours and 8hours. These results were in agreement with Raman Spectroscopy analysis where the IG/ID ratio were very small, indicating high defects and impurities in the samples synthesized at reaction time higher than 3hours

Tensile properties of graphene epoxy nanocomposite

In this research, tensile test was conducted to reveal the notable enhancement of Young Modulus and tensile stress composites. Epoxy resin is a cross-linked polymer, thus it has major influence on the properties of polymers generally in hardness, strength, stiffness, brittleness, and better dimensional stability. Epoxy resin plays many roles in industry especially in adhesion process in automotive and aerospace composites. Discovered in 2004, graphene has revealed that it has tremendous mechanical properties and thermal properties. On top of that, addition of graphene to epoxy can lead to innovate in various adhesion industry and structural materials. In this project, an experiment was conducted in various phases which varying with graphene loading ratio, stirring speed, and stirring time. Outcome from this experiment showed that 1.0% of graphene loading with 500 rpm stirring speed and 30 minutes stirring time shows the optimum condition to enhance the measured properties. The enhancement showed are 53.03 % of Young Modulus and 51.19 % for tensile test result compared to the preliminary result. This study clearly stated the enhancement of mechanical properties of epoxy composites by merely adding 1 wt.% graphene

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Fabrication of polypropylene membrane via thermally induced phase separation as a support matrix of tridodecylamine supported liquid membrane for Red 3BS dye removal

The separation of reactive Red 3BS ions across supported liquid membrane (SLM) process using tridodecylamine as a carrier and sodium hydroxide as a stripping agent was studied. A microporous polypropylene membrane fabricated using thermally induced phase separation technique was used as a membrane support for the SLM process. Three polymer concentrations (10, 15, and 20 wt%) and two quenching temperatures (7 and 29°C) were applied for the polymer-diluent solution. The results demonstrated that all membranes appeared with similar morphologies but different in pore size and porosity. The membrane with 15 wt% polymer concentration quenched at 29°C produced a microporous membrane with a symmetric structure, defined pore size, and performed high stability toward reactive dye extraction, thus feasible to be used as the support material. This membrane had successfully removed and recovered almost 100 and 58% of Red 3BS from an aqueous solution, respectively. Besides, it also exhibited high stability up to 25.5 h of extraction, hence demonstrating an improved performance for the separation of reactive dyes using SLM process

Red 3BS dye extraction in liquid surfactant membrane using continuous extractive reactor process

Nowadays, the use of liquid membrane process in treating dye waste solution is more preferable compared to the batch mode as it provides higher recovery performance and huge treated volume. The aim of this paper is to determine the extraction efficiency of using continuous liquid surfactant membrane (CLSM) process for extraction of reactive dye Red 3BS in order to ensure that LSM process more applicable and commercialize in industries. Liquid membrane process comprises of three liquid phases which are external (dye aqueous solution), organic liquid membrane and internal aqueous phase was developed. Liquid membrane and internal aqueous phase were emulsified and dispersed into the wastewater solution (feed/dye aqueous phase) to be treated. The organic liquid membranes contain Aliquat 336, D2EHPA, Sorbitan Monooleote (Span 80) and kerosene as an extractant, synergist extractant surfactant and diluents, were used respectively. The sodium hydroxide (NaOH) was used as stripping agent in internal aqueous phase for the recovery process. The main factors studied for continuous dye extraction process were agitation speed, retention lime and treatment ratio. The system shows stable performance within 15 min duration of continuous extraction time along the process. The results showed that almost 100 % of Reactive Red 3BS ions were successfully extracted at the optimum conditions of 250 rpm agitation speed, 1: 7 of treatment ratio and 5 min of retention time. Therefore, as a conclusion, CLSM can be proposed as a very promising method for extraction of Red 3BS

Valorization of palm oil mill sterilization condensate via synergistic green reactive extraction of bioactive compounds

Palm oil mill (POM) sterilization condensate is recognized as the source of polyphenols with interesting biological activities, for example, inflammatory processes prevention, UV protection, antioxidant, antimicrobial, and anticarcinogen. Reactive extraction is one of the promising methods for bioactive compounds (polyphenols) recovery offering various merits such as simple, efficient, easy to scale up, and high selectivity. In this work, reactive extraction of polyphenols from POM sterilization condensate using synergistic organic formulation was investigated. The extraction was performed by screening several base and synergist extractants using palm cooking oil as a green diluent. The results showed that about 85% of polyphenols were extracted using 0.25 M 1-Octanol and 0.05 M Aliquat 336 with a synergistic coefficient of 2.59. Meanwhile, the back-extraction study demonstrated that 0.3 M NaOH was selected as the most appropriate stripping agent where almost 100% of stripping performance was achieved. Therefore, the synergistic green formulation offers great potential for polyphenols recovery from POM sterilization condensate