Engineering Design of a Health Service Station Sewage Treatment Station under COVID-19 Epidemic

Health service station is a place in which close contacts with the COVID-19 and other key populations are centralized quarantined for medical observation.A newly built health service station is equipped with 4 700 beds and a supporting sewage treatment station with a designed treatment scale of2 200 m~3/d.The treatment process consists of enhanced biological treatment system,sewage virus disinfection and sterilization system,aerosol disinfection and sterilization system and sludge disinfection and sterilization system.After treatment,the effluent and waste gas can meet the limit specified in Discharge Standard of Water Pollutants for Medical Organization （GB 18466-2005）.The average COD,NH3-N and SS in effluent are 14.53 mg/L,1.26 mg/L and 9.11 mg/L,respectively,and the average concentrations of H2S,NH3 and odor at the outlet are 0.01 mg/L,0.8 mg/L and 6.3,respectively.The sludge is disinfected regularly and then transported outside for disposal.This project can provide reference for sewage treatment design of emergency medical temporary isolation and observation facility and cabin hospital.

Template for Extended Abstract contributions to INDOOR AIR 2022

This investigation presents results of Computational Fluid Dynamics (CFD) modelling of aerosol behaviour within an arbitrary 'realistic' 100m2 office environment, with dynamic and variable respiratory droplet release profile applied based on published findings (Morawska et al., 2009). A multitude of ventilation strategies and configurations have been applied to the base model to compare the effectiveness of reducing the concentration of suspended aerosols over time. A key finding of the investigation indicates a relatively low sensitivity to increasing outside air percentage, and that the benefit from this strategy is heavily dependent on the in-duct droplet decay factor. The application of local recirculating air filtration systems with MERV-13 filters mounted on occupant desks proved significantly more effectiveness than increasing outside air concentration from 25% to 100% in reducing the quantity of suspended aerosols. This highlights that the ventilation industry should perhaps focus on opportunities to integrate filtration systems into furniture, partitions, cabinetry etc., and that an appliance-based solution may be more beneficial for reducing COVID-19 transmission in buildings (and likely more straightforward) than modifications to central ventilation systems, particularly in the application of refurbishments and retrofits. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.

Environment and health co-benefits of vehicle emission control policy in Hubei, China

Vehicle exhaust has been important source of atmospheric pollution in China. In terms of the environmental effects of vehicle emission control policies (VECPs), changes in air pollutants and greenhouse gases (GHG) emissions are receiving increasing attention. Hubei has implemented many traffic controls to accelerate pollution abatement. However, few studies have reported how they would affect pollutant emissions in Hubei in the future, as most concentrate on assessments during COVID-19. Further, there has been little research on whether these controls bring observable health benefits. Thus, this study comprehensively evaluates the emission of major air pollutants (including NOx, CO, VOCs, PM2.5, PM10, and PMTSP) and GHGs (CO2, CH4, and N2O) from the transportation sector concerning different VECPs in Hubei during 2015–2050, together with health outcomes. It highlights that individual VECPs contribute differently to environmental and health benefits, encouraging innovation in mechanisms and technologies to mitigate atmospheric pollution while generating health benefits.

Aerodynamic performance of a ventilation system for droplet control by coughing in a hospital isolation ward.

Over 766 million people have been infected by coronavirus disease 2019 (COVID-19) in the past 3 years, resulting in 7 million deaths. The virus is primarily transmitted through droplets or aerosols produced by coughing, sneezing, and talking. A full-scale isolation ward in Wuhan Pulmonary Hospital is modeled in this work, and water droplet diffusion is simulated using computational fluid dynamics (CFD). In an isolation ward, a local exhaust ventilation system is intended to avoid cross-infection. The existence of a local exhaust system increases turbulent movement, leading to a complete breakup of the droplet cluster and improved droplet dispersion inside the ward. When the outlet negative pressure is 4.5 Pa, the number of moving droplets in the ward decreases by approximately 30% compared to the original ward. The local exhaust system could minimize the number of droplets evaporated in the ward; however, the formation of aerosols cannot be avoided. Furthermore, 60.83%, 62.04%, 61.03%, 60.22%, 62.97%, and 61.52% of droplets produced through coughing reached patients in six different scenarios. However, the local exhaust ventilation system has no apparent influence on the control of surface contamination. In this study, several suggestions with regards to the optimization of ventilation in wards and scientific evidence are provided to ensure the air quality of hospital isolation wards.

Mitigation of breathing contaminants: Exhaust location optimization for indoor space with impinging jet ventilation supply

Densely occupied spaces (e.g., classrooms) are generally over-crowded and pose a high risk of cross-infection during the pandemic of COVID-19. Among various ventilation systems, impinging jet ventilation (IJV) system might be promising for such spaces. However, the exhaust location of the IJV system used for densely occupied classrooms is unclear. This study aims to investigate the effects of exhaust location on the removal of exhaled contaminants in a classroom (15 × 7 × 5 m3) occupied by 50 students. Exhaled contaminants are modeled by a tracer gas released at the top of each manikin. The reference case has three exhausts evenly distributed in the ceiling. The results indicate that: a) a recirculation airflow entraining exhaled contaminants exists above the occupied zone;b) this recirculation air flow entrains contaminants and accumulates them at the upper part of the room near the diffuser;c) locating merely one exhaust on the same side of the supply diffuser leads to the best indoor air quality, i.e., it reduces the mean age of air from 278 s to 243 s, the mass fraction of CO2 from 753 ppm to 726 ppm, and the concentration of tracer gas from 305 ppm to 266 ppm;d) this layout still performs the best when the supply velocity drops to 0.5 m/s. It is worth noting that the proposed layout has fewer exhausts than the reference case but performs better. These results conclude that the exhaust for large spaces is not evenly distributed but depends on the indoor airflow pattern: the key is locating the exhaust near the region with high contaminant concentration. Factors determining the recirculation airflow are suggested to be further studied. © 2023 Elsevier Ltd

Effects of Alcohol-Blended Waste Plastic Oil on Engine Performance Characteristics and Emissions of a Diesel Engine

The current study aims to investigate and compare the effects of waste plastic oil blended with n-butanol on the characteristics of diesel engines and exhaust gas emissions. Waste plastic oil produced by the pyrolysis process was blended with n-butanol at 5%, 10%, and 15% by volume. Experiments were conducted on a four-stroke, four-cylinder, water-cooled, direct injection diesel engine with a variation of five engine loads, while the engine's speed was fixed at 2500 rpm. The experimental results showed that the main hydrocarbons present in WPO were within the range of diesel fuel (C13–C18, approximately 74.39%), while its specific gravity and flash point were out of the limit prescribed by the diesel fuel specification. The addition of n-butanol to WPO was found to reduce the engine's thermal efficiency and increase HC and CO emissions, especially when the engine operated at low-load conditions. In order to find the suitable ratio of n-butanol blends when the engine operated at the tested engine load, the optimization process was carried out by considering the engine's load and ratio of the n-butanol blend as input factors and the engine's performance and emissions as output factors. It was found that the multi-objective function produced by the general regression neural network (GRNN) can be modeled as the multi-objective function with high predictive performances. The coefficient of determination (R2), mean absolute percentage error (MAPE), and root mean square error (RSME) of the optimization model proposed in the study were 0.999, 2.606%, and 0.663, respectively, when brake thermal efficiency was considered, while nitrogen oxide values were 0.998, 6.915%, and 0.600, respectively. As for the results of the optimization using NSGA-II, a single optimum value may not be attained as with the other methods, but the optimization's boundary was obtained, which was established by making a trade-off between brake thermal efficiency and nitrogen oxide emissions. According to the Pareto frontier, the engine load and ratio of the n-butanol blend that caused the trade-off between maximum brake thermal efficiency and minimum nitrogen oxides are within the approximate range of 37 N.m to 104 N.m and 9% to 14%, respectively.

Pandemic restrictions in 2020 highlight the significance of non-road NOx sources in central London

Fluxes of nitrogen oxides (NOx=NO+NO2) and carbon dioxide (CO2) were measured using eddy covariance at the British Telecommunications (BT) Tower in central London during the coronavirus pandemic. Comparing fluxes to those measured in 2017 prior to the pandemic restrictions and the introduction of the Ultra-Low Emissions Zone (ULEZ) highlighted a 73 % reduction in NOx emissions between the two periods but only a 20 % reduction in CO2 emissions and a 32 % reduction in traffic load. Use of a footprint model and the London Atmospheric Emissions Inventory (LAEI) identified transport and heat and power generation to be the two dominant sources of NOx and CO2 but with significantly different relative contributions for each species. Application of external constraints on NOx and CO2 emissions allowed the reductions in the different sources to be untangled, identifying that transport NOx emissions had reduced by >73 % since 2017. This was attributed in part to the success of air quality policy in central London but crucially due to the substantial reduction in congestion that resulted from pandemic-reduced mobility. Spatial mapping of the fluxes suggests that central London was dominated by point source heat and power generation emissions during the period of reduced mobility. This will have important implications on future air quality policy for NO2 which, until now, has been primarily focused on the emissions from diesel exhausts.

Risk Factors for Respiratory Viral Infections: A Spotlight on Climate Change and Air Pollution.

Climate change has both direct and indirect effects on human health, and some populations are more vulnerable to these effects than others. Viral respiratory infections are most common illnesses in humans, with estimated 17 billion incident infections globally in 2019. Anthropogenic drivers of climate change, chiefly the emission of greenhouse gases and toxic pollutants from burning of fossil fuels, and the consequential changes in temperature, precipitation, and frequency of extreme weather events have been linked with increased susceptibility to viral respiratory infections. Air pollutants like nitrogen dioxide, particulate matter, diesel exhaust particles, and ozone have been shown to impact susceptibility and immune responses to viral infections through various mechanisms, including exaggerated or impaired innate and adaptive immune responses, disruption of the airway epithelial barrier, altered cell surface receptor expression, and impaired cytotoxic function. An estimated 90% of the world's population is exposed to air pollution, making this a topic with high relevance to human health. This review summarizes the available epidemiologic and experimental evidence for an association between climate change, air pollution, and viral respiratory infection.

Investigating impacts of COVID-19 on urban mobility and emissions.

The COVID-19 pandemic has severely impacted human activities in a way never documented in modern history. The prevention policies and measures have abruptly changed well-established urban mobility patterns. In this context, we exploit different sources of urban mobility data to gain insights into the effects of restrictive policies on the daily mobility and exhaust emissions in pandemic and post-pandemic periods. Manhattan, the most densely populated borough in New York City, is chosen as the study area. We collect data generated by taxis, sharing bikes, and road detectors between 2019 and 2021, and estimate exhaust emissions using the COPERT (Computer Programme to calculate Emissions from Road Transport) model. A comparative analysis is conducted to identify important changes in urban mobility and emission patterns, with a particular focus on the lockdown period in 2020 and its counterparts in 2019 and 2021. The results of the paper fuel the discussion on urban resilience and policy-making in a post pandemic world.

Short-Term Use Biocontainment Bubbles: Innovative Source Containment of Potentially Infectious SARS-CoV-2 Aerosols.

Introduction: This article will review the processes utilized to develop simple effective containment engineering controls. Short-Term Use Biocontainment Bubbles-Yale (STUBB-Ys), as Yale refers to them, were designed, built, tested, and implemented to protect members of the Yale University community from exposure to SARS-CoV-2 aerosols. STUBB-Ys were designed and created in conjunction with end users, constructed by Environmental Health and Safety (EHS) or partner groups, and tested onsite after installation to verify effective operation and containment. Methods: A wide variety of devices in different settings were developed and installed. STUBB-Ys were used at COVID-19 indoor test centers, laboratories, and clinics. The devices were pursued to create infection prevention measures where existing processes could not be utilized or were inadequate. Each STUBB-Y was tested with a C-Breeze Condensed Moisture Airflow Visualizer to generate smoke and a Fluke 985 Particle Counter, which gives the particle counts from 0.3 to 10 µm to measure particle escape visually and quantitatively. Airflow rates were also tested where applicable with a TSI VelociCalc 9525 Air Velocity Meter. Results: Students and faculty were able to safely continue vital research or clinical study in the targeted areas with the addition of these simple containment devices to confine aerosols. Conclusion: From a biorisk management point of view, EHS was able to confine aerosols at their potential source using simple designs and equipment and adhering to the hierarchy of controls. This article demonstrates how a straightforward design process can be used to enhance worker protection during a pandemic.

Green Construction Technology Demonstration Projects in Civil Buildings under the Environment of Energy Conservation and Emission Reduction

Data innovation has made the social improvement encountered another significant change, nearly covering and infiltrating into varying backgrounds. Structural designing plan, with its primary qualities: enormous designing plan;large measure of estimation;Long plan cycle;the power of work is high. With the persistent advancement of data innovation in structural designing plan, different sorts of assistant plan innovations addressed by PCs have step by step appear, which have effectively settled the above troubles and extraordinarily decreased the trouble of structural designing plan. In this way it very well may be seen that the improvement of data innovation has carried limitless advantages to the general public. Consequently, how to additionally apply data innovation to structural designing and carry immense advantages to structural designing has turned into the focal point of ebb and flow research. Copyright © 2022, Anka Publishers. All rights reserved.

Influence of the ventilation strategy on the respiratory droplets dispersion inside a coach bus: CFD approach

The airborne transmission of the COVID-19 virus was considered the main cause of infection. The increasing concern about the virus spread in confined spaces, characterized by high crowding indexes and an often-inadequate air exchange system, pushes the scientific community to the design of many studies aimed at improving indoor air quality. The risk of transmission depends on several factors such as droplet properties, virus characteristics, and indoor airflow patterns. The main transmission route of the SARS-CoV-2 virus to humans is the respiratory route through small (<100 μm) and large droplets. In an indoor environment, the air exchange plays a fundamental role on the dispersion of the droplets. In this study, an integrated approach was developed to evaluate the influence of the ventilation strategy on the dispersion of respiratory droplets emitted inside a coach bus. There are no specific guidelines and standards on the air exchange rate (AER) values to be respected in indoor environments such as coach buses. The aim of this work is to analyse the influence of ventilation strategy on the respiratory droplet concentration and distribution emitted in a coach bus. Ansys FLUENT was used to numerically solve the well-known transient Navier-Stokes equations (URANS equations), the energy equation and using the Lagrangian Discrete Phase Model (DPM) approach to construct the droplet trajectories. The geometry is representative of an intercity bus, a vehicle constructed exclusively for the carriage of seated passengers. The 3D CAD model represented a coach bus with an HVAC system, within which an infected subject was present. The positions of exhaust vents and air-conditioning vents were chosen to ensure complete air circulation throughout the bus. The infected subject emitted droplets with a well-defined size distribution and mass through the mouth. The air exchange is provided in two different ways: general ventilation (from air intakes positioned along the bus windows and top side of central corridor) and personal ventilation (with air intakes for each passenger). For the general ventilation a single AER value was set (0.3 m3 s−1). The first results obtained showed a slight particle dispersion in the computational domain due to the airflow rate entered through the HVAC system, but a still elevated level of particle concentration tended to accumulate on the area near to infected subject. Additional analysis was executed to evaluate the beneficial effects linked to further addition of airflow through personal air-conditioning vents placed above every passenger's head. The results show the importance of the use of the ventilation system inside a coach bus, highlighting how the contribution linked to of the personal air exchange rate can lead to a significant reduction of droplet concentration exposure and consequently a reduction of the risk of infection from airborne diseases.

Ventilation Cfd Analysis at an Classroom as a Tool for Air Safety Verification under Covid19 Context, a Case Study

The COVID 19 pandemic has struck the global economy and slowed down human activity. Paraguay, a small South-American country, was not an exception. This work results from the urgent need to reopen universities, schools, and other academic institutions to resume teaching activities in light of restrictive access to online learning in Paraguay. In order to contain the spread of this virus, school activities such as course lectures were placed on hold indefinitely. Inappropriate airflow in an enclosed space is one of the main factors in the spread of this virus. When combined with personal protective equipment, proper air ventilation and air replacement can significantly reduce this airborne virus's spread. Potential sources of contaminant accumulation are stagnant locations of air in a closed volume. It is, therefore, essential to first identify these hot spots. Utilizing computational tools, such as CFD, an airflow analysis can be conducted to see any potential stagnant point. In the case of a classroom, it will then allow proper airflow by avoiding stagnant points by moving furniture, equipment, and chairs in combination to adding walls and opening windows and doors. This type of CFD study will set the benchmark for future classroom layout standards in this pandemic background. The work discussed here is a case study on a 300 student classroom at the Faculty of Engineering at the National University of Asuncion. The CFD results showed detailed infounation on flow patterns and velocity profiles in the analyzed classroom environment and air cycle and exhaust results. The six air conditioning systems blowing 300 CFM each, combined with eight fans installed at the ceiling, forced air to recirculate and helped to remove old air to the windows and suction some new air from doors. This helped university administrators to reopen some class areas and keep their faculties and students safe for lectures. It is important to remark here that air reposition could be measured, showing 200 CFM air removal in this first simulation run. Further analysis with a different internal layout will be needed to see if any improvements can be made. It is expected to have a much better air removal by adding a localized exhaust fan. This work suggests the location of each location's outlet points and flows capacity to ensure proper ventilation is achieved in this particular case study. Other academic institutions are showing interest in implementing this computational tool to design classroom layout as well as ventilation schemes.

SO2 compliance monitoring and emission characteristics analysis of navigating ships: A case study of Shanghai waters in emission control areas, China

For the purpose of monitoring the emission compliance of navigating ships in key waters of Shanghai, the present study adopts a sniffing method involving an unmanned aerial vehicle (UAV) platform-based ship exhaust mini-sniffing system measuring the concentrations of SO2 and CO2 within the plumes of navigating ships, then estimating the fuel sulfur content (FSC) of ship. The proposed method aims to provide a low-cost, non-contact method to assess the compliance level of FSC of navigating ships. Experimental tests were performed on ships in the Yangtze River Estuary and the core section of the Huangpu River, the key waters of Shanghai. 679 ships were monitored in the experiment, of which 13 ships were monitored by UAV with FSC greater than 0.5% (m/m). Due to the prevention and control of the COVID-19 pandemic, 8 monitored ships were intercepted by maritime law enforcement(MLE), and fuel oil samples were collected and analyzed in laboratory. The results show that the FSC of the 8 ships was greater than the limit of 0.5% (m/m). Finally, the monitoring results are comprehensively analyzed according to different ship lengths, types, nationalities and water areas. From the experimental results, it can be concluded that the FSC of Chinese cargo ships with length in the range of 80–160 m is more likely to exceed the standard 0.5%(m/m). The probability of exceeding the standard 0.5%(m/m) of navigating ships in the Yangtze River is higher than that of the Huangpu River. Overall, the presented study provides a reference for ship supervision in emission control areas (ECAs), which can improve the efficiency of MLE.

Integrated system of exhaust air heat pump and advanced air distribution for energy-efficient provision of outdoor air.

A large outdoor air supply is required to control the airborne infection risk of respiratory diseases (e.g., COVID 19) but causes a high energy penalty. This study proposes a novel integrated system of the exhaust air heat pump and advanced air distribution to energy-efficiently provide outdoor air. The system energy performances are evaluated by the experimentally validated thermodynamic model of heat pump and heat removal efficiency model of advanced air distribution. Results show the exhaust air heat pump with advanced air distribution can save energy because of three mechanisms. First, the exhaust air heat pump reuses the exhaust air to reduce the condensation temperature, thereby improving the coefficient of performance. Second, advanced air distribution reduces ventilation load. Third, advanced air distribution reduces the condensation temperature and enhances the evaporation temperature, thereby improving the coefficient of performance. The exhaust air heat pump saves energy by 18%, advanced air distribution saves energy by 36%, and the integrated system of the exhaust air heat pump and advanced air distribution can save energy by 45%. As a specific application, compared with the conventional system (i.e., the outdoor air heat pump with mixing ventilation), the exhaust air heat pump with stratum ventilation saves energy by 21% - 35% under various outdoor air ratios and outdoor air temperatures. The proposed integrated system of the exhaust air heat pump and advanced air distribution contributes to the development of low-carbon and healthy buildings.

Measuring Pollution Control and Environmental Sustainable Development in China Based on Parallel DEA Method

The purpose of this study is to explore the impact of pollution control on industrial production efficiency in 31 provinces and cities in the Yellow River and Non-Yellow River basins in China from 2013 to 2017, using the methods of the directional distance function (hereinafter referred to as DDF) and the technology gap ratio (hereinafter referred to as TGR) in parallel, while taking the industrial production sector (labor force, total capital formation, energy consumption and industrial water consumption) and the pollution control sector (wastewater treatment funds and waste gas treatment funds) as input variables. Undesirable outputs (total wastewater discharge, lead, SO2 and smoke and dust in wastewater) and an ideal output variable (industrial output value) are taken as output variables. It is found that the total efficiency of DDF in the Non-Yellow River Basin is 0.9793, which is slightly better than 0.9688 in the Yellow River Basin. Among the 17 provinces and cities with a total efficiency of 1, only Shandong and Sichuan are located in the Yellow River Basin. The TGR values of 31 provinces, cities and administrative regions are less than 1, and the average TGR value of the Yellow River Basin is 0.3825, which is lower than the average TGR value of the Non-Yellow River Basin of 0.5234. We can start by improving the allocation of manpower and capital, implementing the use of pollution prevention and control funds, improving the technical level of industrial production, improving pollutant emission, and increasing output value to improve overall efficiency performance. This study uses the parallel method, taking the industrial production department and the pollution control department as inputs, to objectively evaluate the changes in industrial production efficiency and technology gap in the Yellow River and Non-Yellow River basins, which is conducive to mastering the situation of pollution control and industrial production efficiency, and provides the reference for SDG-6- and SDG-9-related policy making.

IoT System Design of Thermoelectric Generator for Harvesting Motorcycle Exhaust Heat Energy

Online food delivery is the latest trend to hit the world. This trend has increased rapidly in recent years as a result of the COVID-19 pandemic, which struck at once changing the country’s economic landscape. Therefore, motorcycles and mobile phones with high data access and battery storage capacity are used mainly involving identifying the place of delivery. Due to the widespread and frequent use of cellular phones in tracking the position of food delivery then causing the cellular phone battery storage will be depleted and require recharging the phone which involves a long time. This in turn will cause delays in the food delivery procedure. The development of a Thermoelectric Generator system using the Internet of Things (IoT) for energy harvesting is very important. Given that the development method is based on the differential temperature on the exhaust chamber of the motorcycle and heatsink to solve the problem of charging a cellular phone on a motorcycle. The process of developing this system requires control over the voltage capacity as well as the ability to monitor it online through the Internet of Things system. The development of this system revealed that large temperature difference rates produce high electrical voltages to 10 V with power rates up to 206 mW. It also shows that the quantity of TEG will affect the rate of voltage increase and the value of power produced in direct proportion as the quantity of TEG increases. In conclusion, the benefits of temperature changes will generate reusable energy for daily use. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

Environmental Benefits and Energy Savings from Gas Radiant Heaters’ Flue-Gas Heat Recovery

This paper demonstrates the need and potential for using waste heat recovery (WHR) systems from infrared gas radiant heaters, which are typical heat sources in large halls, due to the increasing energy-saving requirements for buildings in the EU and the powerful and wide-spread development of the e-commerce market. The types of gas radiant heaters are discussed and the classification of WHR systems from these devices is performed. The article also presents for the first time our innovative solution, not yet available on the market, for the recovery of heat from the exhaust gases of ceramic infrared heaters. The energy analysis for an industrial hall shows that this solution allows for environmental benefits at different levels, depending on the gas infrared heater efficiency, by reducing the amount of fuel and emissions for domestic hot water (DHW) preparation (36.8%, 15.4% and 5.4%, respectively, in the case of low-, standard- and high-efficiency infrared heaters). These reductions, considering both DHW preparation and hall heating, are 16.1%, 7.6% and 3.0%, respectively. The key conclusion is that the innovative solution can spectacularly improve the environmental effect and achieve the highest level of fuel savings in existing buildings that are heated with radiant heaters with the lowest radiant efficiency.

Effect of Al2O3 Nanoparticles on Performance and Emission Characteristics of Diesel Engine Fuelled with Diesel–Neem Biodiesel Blends

Indagation in the sphere of nanoparticle utilisation has provided commendatory upshots in discrete areas of application varying from medicinal use to environmental degradation alleviation. This study incorporates alumina nanoparticles as additives to diesel and biodiesel blends. The prime objective of the present study was the scrutinisation of the denouement of Al2O3 nanoparticle incorporation in diesel–biodiesel blends on a diesel engine’s performance and emission characteristics. Test fuel samples were prepared by blending different proportions of biodiesel and dispersing two concentrations of alumina nanoparticles (25 and 50 ppm) in the diesel. Dispersion was made without the use of a nanoparticle stabiliser to meet real-world feasibility. High-speed shearing was employed to blend the biodiesel and diesel, while nanoparticles were dispersed in the blends by ultrasonication. The blends so devised were tested using a single-cylinder diesel engine at fixed RPM and applied load for three compression ratios. Upshots of brake-specific fuel consumption (BSFC) and brake thermal efficiency (BTE) for fuel samples were measured with LabView-based software, whereas CO emissions and unburnt hydrocarbon (UBHC) emissions were computed using an external gas analyser attached to the exhaust vent of the engine. Investigation revealed that the inclusion of Al2O3 nanoparticles culminates in the amelioration of engine performance along with the alleviation of deleterious exhaust from engine. Furthermore, the incorporation of alumina nanoparticles assisted in the amelioration of dwindled performance attributed to biodiesel blending. More favourable results of nanoparticle inclusion were obtained at higher compression ratios compared to lower ones. Reckoning evinced that the Al2O3 nanoparticle is a lucrative introduction for fuels to boost the performance and dwindle the deleterious exhaust of diesel engines.

Comparison of ventilation strategies in intensive care units for airborne infection control

Healthcare facilities are one of the most important buildings in an outbreak. With the tremendous increment of bed occupancy rates in intensive care units, cross-infection risks to healthcare workers also increase. Along with the personal and societal measures, airborne infection prevention via ventilation systems should be evaluated in detail for each design. In this study, the infection prevention performances of three different ventilation layouts inside a selected intensive care unit design, located in Gazi University Hospital, are compared. Three different ventilation strategies as conventional (head supply-feet exhaust, Case 1), switched (head exhaust-feet supply, Case 2), and local exhaust (Case 3) are evaluated with respect to their aerosol distribution characteristics, airflow patterns, and temperature distribution characteristics. As a result, aerosol removal efficiencies of conventional, switched, and local-exhaust approaches are found to be 18.7%, 68.3%, and 97.8%, respectively, whereas the temperature distribution in Case 3 may also meet the thermal comfort requirements.