Summer Days Research Articles

Visitor motivations and design feature use for thermal comfort on hot days in Bochum City Park, Germany

The rising incidence of extreme heat in urban areas poses challenges to urban living, affecting thermal comfort and public health. Public green spaces (PGS), such as parks, play a crucial role in mitigating heat as 'cooling oases' that enhance visitors' thermal comfort and offer various other ecosystem services. Despite their importance, the specific role of thermal comfort in motivating individuals to visit PGS remains unclear. This study aims to clarify the connection between thermal comfort and PGS visits on hot days, with a focus on visitor motivations and the park features that promote comfort. We conducted systematic observations involving quantitative counts of PGS visitors and rapid questionnaires on summer days of varying temperature ranges in Bochum City Park, Germany. Results indicated that the motivation to achieve thermal comfort by visiting the park significantly increased from ‘slightly warm’ to ‘warm’ days, especially among older visitors, and was independent of other motivations for visiting. Furthermore, results showed that the perceived temperature has a limited impact on the use of PGS features, with sun exposure emerging as a decisive factor. These insights can inform the planning and design of PGS to create inviting and thermally comfortable environments serving as cooling oases for urban residents. The findings offer valuable insights that can inform the planning and design of public green spaces, with the aim of creating desirable and thermally comfortable environments as cooling oases for urban residents.

Microscale urban heat variability and time-location patterns: Elevated exposure for bikers and rickshaw drivers beyond average city temperatures in megacity

Urban heat island effect creates diverse microclimates, influencing heat exposure and consequent health effects. Study measured heat exposure among delivery riders within their microclimate, comparing it with city's average temperature. We investigated how higher exposure affects work, health, and productivity of riders.For 21 days in winter and summer, we measured heat exposure during peak hours (under sun and shade) in riders' immediate environment, at seven high-traffic routes in Karachi, Pakistan. Recorded temperature were compared with city's ambient air temperature. In-depth interviews were conducted to assess the impacts on riders' health, welfare, and productivity.During winter, temperature was 5.0 °C higher under sun and 1.6 °C higher under shade, as compared to city average recorded temperatures. In summer temperature was 5.5 °C higher under sun and 1.8 °C higher in shade as compare to recorded city's average air temperature. Riders reported exhaustion, reduced productivity, income loss, and negative impacts on social wellbeing during hot days. For mitigation riders relied on strategies like staying hydrated and taking breaks from work under shades. Study demonstrated higher exposure to heat for riders in megacity as compare to city's recorded temperature. This led to reduced productivity and income losses, emphasizing need for urgent initiatives to safeguard riders' well-being.

Multi-Domain Environmental Quality of Indoor Mixed-Use Open Spaces and Insights into Healthy Living—A Quarantine Hotel Case Study

In the post-pandemic context, data-driven design interventions that can endow architectural spaces with mixed-use and open characteristics that are adaptable and environmentally resilient are increasingly important. Ubiquitous semi-public architecture, such as hotel buildings, plays a crucial role in public health emergencies. Many hotels adopt mixed-use and open room spatial layouts, integrating diverse daily functions into a single tiny space, fostering flexible utilization and micro-scale space sharing; however, these also introduce potential health risks. This study offers a comprehensive evaluation of the indoor environmental quality (IEQ) of a hotel room space and discusses feasible intervention strategies for healthier renovation and rehabilitation. Taking a hotel in Shenzhen as a case, a multi-domain environmental assessment was conducted during the COVID-19 quarantine period in the summer of 2022. The study examines the health risks inherent in the hotel’s guest room and the varying patterns of IEQ factors across the hotel’s domains, including volatile organic compound concentrations, physical environmental parameters, and heat stress indices. The results illustrate diverse change trends in the chemical, physical, and heat stress factors present in the tested quarantined hotel room space throughout a typical summer day. Although most of the examined environmental factors meet local and global standards, some problems draw attention. In particular, the PM2.5 concentration was generally observed to be above the World Health Organization (WHO) air quality guideline (AQG) standards, and the interior lighting did not meet required standards most of the time. Moreover, correlation and multiple regression analyses uncover significant influence by physical environmental conditions on the concentrations of chemical pollutants in the hotel room. The study preliminarily identifies that higher relative humidity could lead to a lower concentration of CO2 while a higher PM2.5 concentration. Wet bulb globe temperature (WBGT) was observed to positively affect CO2 concentration. Further, the results suggest that even with relatively rigorous initial adjustment and re-renovation, multi-domain environmental quality in air-conditioned quarantine hotel rooms should be monitored and ameliorated from time to time. Overall, this study offers a scientific foundation for healthier upgrades of existing hotel buildings as well as provides insights into achieving environmental resilience in newly constructed hotel buildings for the post-pandemic era.

Climate change and gastroenteritis projections in Albanian children

Abstract Background Human health can be affected by climate in direct and indirect ways. Increasing temperatures may affect ecosystems, water safety, and exposure to waterborne diseases. This is the first work in Albania aiming to demonstrate the link between gastroenteritis rate and climate in the country. This research was supported by UNICEF Albania through the WASH Global Thematic Fund, but it doesn’t necessarily represent UNICEF’s position. Methods Epidemiological surveillance reports of the period 2006-2022 were used for the yearly incidence of gastroenteritis in children 0-14 years old. Years 2020 and 2021 were not included because of pandemic confounding potential. Historic data for calculating the average summer temperatures were retrieved from timeanddate.com repository. Pearson coefficient is calculated to quantify the associations and linear regression is applied to project the increased rate in the future. Results There was a statistical association between gastroenteritis rate and summer temperatures during the study period (Pearson coefficient=0.78, p = 0.001). There was a tendency that in years with hotter summers higher incidence of gastroenteritis was reported by the health system. For each degree (Celsius) increase in the average summer day temperatures, the risk of gastroenteritis in children is expected to increase by 644/100 000 (CI 95%: 317 - 972). An excess rate of 966/100 000 is expected in the case of Intergovernmental Panel on Climate Change medium scenario projection of 1.5o C average temperature increase. That implies more than 4830 additional new cases every year in children 0-14 years old, attributed to climate change in the future in Albania. Conclusions The analysis demonstrated excess gastroenteritis risk may be related to higher summer temperatures observed in Albania. The expected gastroenteritis risk increase in a warmer future should be addressed by improvements in sanitation, education of parents and epidemiological intelligence. Key messages • A warmer climate is expected to affect the health by increasing the risk for diarrheic diseases. • Children will be the most at-risk population category.

Tragic Optimism in 500 Days of Summer and Her: A Comparative Analysis

This article aims to investigate the portrayal of optimism in two modern films, Marc Webb’s 500 Days of Summer (2009) and Spike Jonzes’s Her (2013), using Viktor Frankl’s concept of optimism. The focus is on the characters’ quest for love and self-discovery in the midst of challenges and emotional turmoil. They present the idea of seeking purpose and personal development while experiencing highly complex emotions. Accordingly, this article scrutinises the storytelling techniques embedded in characters’ notions revealed through their progression in both films to display the intricacies of relationships in today’s world. Films play a role in deepening the grasp of the complicated themes of love, technology, and obsessive passion in today’s world, as well as shed light on persistent psychological challenges with modern ways of storytelling.

Rationale and design of Healthy Kids Beyond the Bell: a 2x2 full factorial study evaluating the impact of summer and after-school programming on children’s body mass index and health behaviors

BackgroundThe Structured Days Hypothesis posits that structure protects children against obesogenic behaviors (e.g., physical inactivity, unhealthy dietary intake) and, ultimately, prevents the occurrence of excessive weight gain. The hours following school (i.e., 3–6 pm school days) and summer vacation are two “windows of vulnerability” when children may experience less structure. Programs that provide a healthy structured environment and may prevent BMI gain exist for both time periods (i.e., after-school programs and summer day camps). Unfortunately, these programs are cost prohibitive for children from low-income families to attend. This study will test the impact of providing vouchers to access existing, community-operated after-school and summer programs on BMI z-score, body composition, and obesogenic behaviors (i.e., physical activity, screen use, diet, and sleep) of children (5–12 years) from schools that primarily serve families with low income.MethodsThe study will employ a 2x2 factorial design. Participants (N = 480) attending 4 elementary schools in one school district will be randomly assigned to a no treatment control, after-school program voucher only, summer day camp voucher only, or after-school and summer day camp vouchers. Vouchers will cover the full cost of attending a pre-existing community-based after-school or summer camp program. The primary outcome (BMI z-score) will be measured at baseline (before end of school year, ~ May), 3-month follow-up (after summer, ~ August), and 12-month follow-up (end the following school year, ~ May). Secondary outcomes include body composition (i.e., whole-body fat mass, fat free mass, and percent body fat) and obesogenic behaviors (i.e., physical activity, sedentary time, sleep, screen-time, and diet). The study will also employ a rigorous process evaluation which will consider after-school and summer camp program attendance and content. Analyses will examine differences between the four groups in BMI z-score, body composition, and obesogenic behaviors. Incremental cost effectiveness ratios will determine the cost effectiveness of the intervention.DiscussionThe current study will provide critical information for researchers, practitioners, and policy makers seeking to combat the childhood obesity epidemic in children from families with low-income during the school year and summer.Trial registrationNCT05880901. Registered 27 May 2023.

Exploratory Analysis of a Novel Modular Green Wall’s Impact on Indoor Temperature and Energy Consumption in Residential Buildings: A Case Study from Belgium

One possible solution that mitigates the effects of climate change is the implementation of vertical greenery systems, which have the potential to reduce the need for cooling and provide energy savings for heating. This paper evaluates the effects of an innovative modular green wall on indoor temperature and energy use in a residential case study building. This research was carried out on a residential house in the city of Ghent, Belgium, whose southwest facade is covered with a specific type of modular green wall (a structure with a specific substrate and plants that have the ability to purify water so that it can be reused in the house). The monitoring process included four different temperatures (in front of and behind the green wall, in the substrate, and on the wall without greenery) during winter and summer periods. To analyze the effect on the internal temperature and energy use, a DesignBuilder simulation model was built and validated against these experimental results. This green wall has proven to have the greatest effect during the hottest summer days by reducing the indoor temperature by up to 3.5 °C. It also effectively increases the indoor temperature by up to 1.4 °C on a cold winter day, leading to energy savings of 6% on an annual basis.

Species composition and distribution of birds in the area of Kyzyl airport (Republic of Tyva, Russia) and their impact on the ornithological situation

Aim. Study and identification of species composition and actual location of birds on the territory of the Kyzyl airport and in the airspace above it throughout the year and assessment of the intensity of the ornithological situation in order to ensure flight safety.The study of avifauna within the airport area within a radius of 15 km was carried out throughout a calendar year using the method of integrated route accounting and stationary observations on the runway. Statistical processing of the field materials was carried out using the Microsoft Excel program.In total, a fairly high species diversity was revealed within the airport territory – 76 species in zone I – R =2,5 km and 199 species in zone II – R= 15 km. The population density of birds points was calculated in points, the status of stay, seasonal fluctuations in the number and species diversity of avifauna and the intensity of the ornithological situation were revealed.Despite the rather high species diversity and significant fluctuations in the number of birds, ornithological intensity in zone II during the year is ‘calm’ and reaches the upper limit of the ‘satisfactory’ level occasionally on certain days of late summer – early autumn. A place of increased concentration of birds within airport area II is an urban landfill. The decision to move the landfill beyond a 50 km radius from the runway, the prevention of nesting of aircraft‐dangerous bird species within zone II and the use of visual repellents will allow maintenance of a low level of ornithological intensity throughout the year.

Effectiveness of Screens Shading Opaque Facades in Terms of Building Thermal Modernisation

Screens used in modernizations of buildings to diversify the facade also provide shade on the walls. The article presents a comparison of the effectiveness of shades with different degrees of shading in terms of energy savings. On summer days, especially when there is a lot of sunlight and air temperatures are above 30°C, the covers reduce the temperature on the outer surface of the wall and, as a result, improve the microclimate of the rooms. Lower temperatures result in less heat accumulated during the day. The results were compared for various masonry materials. Less heat energy accumulated in the wall reduces the energy demand to cool the internal air. Energy savings were estimated over 50 years of building use. A method was proposed to quickly compare the effectiveness of the different shading shields.

Biomimetic Cooling: Functionalizing Biodegradable Chitosan Films with Saharan Silver Ant Microstructures.

The increasing occurrence of hot summer days causes stress to both humans and animals, particularly in urban areas where temperatures can remain high, even at night. Living nature offers potential solutions that require minimal energy and material costs. For instance, the Saharan silver ant (Cataglyphis bombycina) can endure the desert heat by means of passive radiative cooling induced by its triangular hairs. The objective of this study is to transfer the passive radiative cooling properties of the micro- and nanostructured chitin hairs of the silver ant body to technically usable, biodegradable and bio-based materials. The potential large-scale transfer of radiative cooling properties, for example, onto building exteriors such as house facades, could decrease the need for conventional cooling and, therefore, lower the energy demand. Chitosan, a chemically altered form of chitin, has a range of medical uses but can also be processed into a paper-like film. The procedure consists of dissolving chitosan in diluted acetic acid and uniformly distributing it on a flat surface. A functional structure can then be imprinted onto this film while it is drying. This study reports the successful transfer of the microstructure-based structural colors of a compact disc (CD) onto the film. Similarly, a polyvinyl siloxane imprint of the silver ant body shall make it possible to transfer cooling functionality to technically relevant surfaces. FTIR spectroscopy measurements of the reflectance of flat and structured chitosan films allow for a qualitative assessment of the infrared emissivity. A minor decrease in reflectance in a relevant wavelength range gives an indication that it is feasible to increase the emissivity and, therefore, decrease the surface temperature purely through surface-induced functionalities.

Desert Ant (Melophorus bagoti) Dumpers Learn from Experience to Improve Waste Disposal and Show Spatial Fidelity.

The Central Australian red honey-pot ant Melophorus bagoti maintains non-cryptic ground-nesting colonies in the semi-desert habitat, performing all the activities outside the nest during the hottest periods of summer days. These ants rely on path integration and view-based cues for navigation. They manage waste by taking out unwanted food, dead nestmates, and some other wastes, typically depositing such items at distances > 5 m from the nest entrance, a process called dumping. We found that over multiple runs, dumpers headed in the same general direction, showing sector fidelity. Experienced ants dumped waste more efficiently than naive ants. Naive individuals, lacking prior exposure to the outdoor environment around the nest, exhibited much scanning and meandering during waste disposal. In contrast, experienced ants dumped waste with straighter paths and a notable absence of scanning behaviour. Furthermore, experienced dumpers deposited waste at a greater distance from the nest compared to their naive counterparts. We also investigated the navigational knowledge of naive and experienced dumpers by displacing them 2 m away from the nest. Naive dumpers were not oriented towards the nest in their initial trajectory at any of the 2 m test locations, whereas experienced dumpers were oriented towards the nest at all test locations. Naive dumpers were nest-oriented as a group, however, at the test location nearest to where they dumped their waste. These differences suggest that in red honey ants, learning supports waste disposal, with dumping being refined through experience. Dumpers gain greater spatial knowledge through repeated runs outside the nest, contributing to successful homing behaviour.

Free Summer Programming and Body Mass Index Among Schoolchildren From Low-Income Households

Children experience accelerated gains in body mass index (BMI) during the summer months when school is not in session. Children from low-income households are most susceptible. Accelerated BMI gain in summer may be due to the removal of the health-promoting structure provided by schools. During summer, a common form of health-promoting structure is summer day camps (SDCs). Summer day camps are predominately fee for service, which creates a financial barrier for children from low-income households. One solution to mitigate accelerated BMI gain is providing free access to an existing SDC. To investigate whether providing free access to an existing community SDC can mitigate accelerated BMI z score (zBMI) gain in elementary school-age children. This randomized clinical trial was conducted during the summers of 2021, 2022, and 2023 in the southeastern United States. Participants were children (kindergarten through fourth grade) from predominantly low-income households who were randomized to attend an SDC operated by a parks and recreation commission or continue summer as usual (control). Free SDC every weekday (Monday through Friday) for 8 to 10 weeks. The primary outcome was between-group differences in change of zBMI measured before school ended (May) and on return to school from summer (late August). Secondary analyses examined the dose response of zBMI change with parent-reported child attendance at SDCs during the summer for all children (intervention and control). A total of 422 children (mean [SD] age, 8.2 [1.5] years; 202 [48%] female, 220 [52%] male, 292 [69%] at or below 200% federal poverty level, 127 [30%] with food insecurity) were randomized to 1 of 2 conditions: summer as usual (control, n = 199) or free SDC (n = 223). Intent-to-treat analysis indicated mean (SE) change in zBMI at the end of the summer was 0.046 (0.027) for the control and -0.048 (0.025) for the intervention group, representing a significant between-group difference of -0.094 (95% CI, -0.166 to -0.022). Dose-response analyses indicated that every 1 day per week increase in attending an SDC resulted in a -0.034 to -0.018 zBMI reduction, which translates to a gain of 0.046 to 0.080 zBMI for children never attending summer programming vs -0.09 to -0.04 zBMI reduction for children attending summer programming every weekday. Providing children free access to existing community summer programming can have a meaningful effect on children's zBMI gain during the summer. Future studies should replicate these findings across different regions and identify the optimal dose of programming to mitigate unhealthy zBMI gains. ClinicalTrials.gov Identifier: NCT04072549.

Can combined wind and solar power meet the increased electricity load on heatwave days in China after the carbon emission peak? A case study in southern Hebei

Wind and photovoltaic (PV) power are the fastest-growing renewable energy sources; however, they are vulnerable to weather extremes. In the context of global warming, the frequency of extreme weather events, particularly heatwaves (HW), is anticipated to increase. Compared to normal summer days, HW days not only cause a rise in electricity demand but also exhibit a complementary growth in wind/PV generation. Therefore, determining whether the increase in wind/PV generation on HW days can meet the corresponding surge in electricity load is pivotal for replacing fossil fuel-based electricity. To address this question, this study conducts a case study for southern Hebei Province, which has the highest combined wind/PV installations in China, for the period 2031–2040 under the scenario that China will achieve its carbon peak (2030) and carbon neutrality goals as planned. We use recently developed load and wind power models and calibrate a boosting ensemble learning model to simulate PV generation. The results reveal that the total increase in wind/PV generation on HW days can fully meet the total increase in electricity consumption starting in 2039. However, due to the uneven distribution of wind/PV generation and load changes throughout the HW days, 9 GWh of energy storage capacity is required to ensure electricity supply in the early morning hours. Under China's climate change adaptation strategy, Hebei Province can harness wind/PV energy to address peak load demands during HW conditions and initiate climate-resilient urban development pilot projects.

The Increase in Urban Heat Due to Global Warming Can be Significantly Affected by the Structure of the Land Use and Land Cover

ABSTRACTUrban populations are increasingly exposed to excessive heat. Heat distribution in the urban environment can be affected by several factors, including the spatial arrangement of land use/land cover (LULC) that is specific to a given city. This study applies a climate model with urban canopy parameterisation to downscale future climate projections and simulate the spatio‐temporal pattern of heat in the urban environment to better understand the effect of LULC structure on its distribution. Heat conditions are characterised by climate indices that are well representative in two mid‐sized Central European cities of Brno and Ostrava (Czech Republic). Our results show that the annual number of hot days (HOT), summer days (SUD), tropical nights (TRN) and warm nights (WAN) will increase significantly (p < 0.01) in the 21st century in both cities. The model also simulates a more intensive increase and a higher spatio‐temporal variability in all indices in Brno compared to Ostrava. In Brno, the annual number of HOT and TRN is projected to be more than 500% of the 1981–2010 reference period's value by the end of the 21st century under the RCP 8.5 scenario. To determine the causes of the differences in heat distribution, we applied LULC configuration metrics and correlation analysis using various geographical factors. The higher risk of urban heat in Brno compared to Ostrava can be attributed to a more homogenised and less fragmented LULC structure and to the more substantial role of altitude in the complex terrain of Brno. Other factors, such as the presence of impervious surfaces and vegetation, have a similar effect on the variability of the studied indices in both cities. Urban planners should consider the role of the LULC structure and the changes that can be made in a city when designing adaptation measures to mitigate the effects of urban heat.

The pace of change of summertime temperature extremes

Summer temperature extremes can have large impacts on humans and the biosphere, and an increase in heat extremes is one of the most visible symptoms of climate change. Multiple mechanisms have been proposed that would predict faster warming of heat extremes than typical summer days, but it is unclear whether this is occurring. Here, we show that, in both observations and historical climate model simulations, the hottest summer days have warmed at the same pace as the median globally, in each hemisphere, and in the tropics from 1959 to 2023. In contrast, the coldest summer days have warmed more slowly than the median in the global average, a signal that is not simulated in any of 262 simulations across 28 CMIP6 models. The observed stretching of the cold tail indicates that observed summertime temperatures have become more variable despite the lack of hot day amplification. The interannual variability and trend in the warming of both hot and cold extremes compared to the median can be explained from a surface energy balance perspective based on changes in net surface radiation and evaporative fraction. Tropical hot day amplification is projected to emerge in the future (2024-2099, SSP3-7.0 scenario), while Northern Hemisphere heat extremes are expected to continue to follow the median.

Ultraviolet radiation thin film dosimetry: A review of properties and applications.

Spectroradiometry, radiometry, and dosimetry are employed for the measurement of ultraviolet radiation (UVR) irradiance and non-ionizing exposure. Different types of UVR dosimeter have been developed for measuring personal and environmental UVR exposures since film dosimetry was pioneered in the 1970s. An important type of dosimeter is the thin film variant, which contains materials that undergo changes in optical absorbance when exposed to UVR. These changes can be measured at a specific wavelength using a spectrophotometer. Thin film dosimeters allow UVR exposure measurements on humans at various body sites during daily activities, as well as on plants, animals, and any sites of interest when utilized in a field environment. This review examines the properties and applications of five types of thin film UVR dosimeter that have different dynamic exposure limits and spectral responses. Polysulphone, with a spectral response approximating the human erythema action spectrum, was one of the first materials employed in thin film form for the measurement of UVR exposures up to 1 day, and up to 6 days with an extended dynamic range filter. Polyphenylene oxide has been characterized and employed for personal UVR exposure measurements up to approximately four summer days and has also been used for long-term underwater UVR exposures. Phenothiazine and 8-methoxypsoralen have been reported as suitable for the measurement of longer wavelength UVA exposures. Finally, polyvinyl chloride with an extended dynamic exposure range of over 3 weeks has been shown to have predominantly a spectral response in the UVB and extending up to 340 nm.

Measurement of Innovative Green Façades in the Central European Climate

Green structures, such as green roofs or green façades, are great examples of climate change mitigation. Their impact is mainly focused on roofs in the area of overheating reduction. In this paper, initial measurement results of a green façade experimental test setup are provided. The green façade uses an innovative board from recycled materials with vegetation rooted directly on the board. The tested green façade is divided into three segments. These segments differ from each other in their watering regimes, which are crucial for cooling effectiveness. Watering operates with the assistance of gravity; water flows from the top gutter through the boards. In this paper, these three segments are compared to each other with respect to temperatures on the surface of a regular external thermal insulation composite system façade (ETICS) during two summer days. The green façade showed an impact on the temperature in the ventilated air gap, where the temperature is almost the same as the outdoor air temperature in the morning with direct solar radiation on the façade and lower than the outdoor air temperature in the afternoon. At the peaks, the surface temperatures within the air cavity surface are up to 8 °C lower than those on a new white ETICS coating. This demonstrates a cooling potential, although the surface temperatures are always higher than the outdoor air temperatures during daylight hours.

Facile and efficient superhydrophobic film for radiative daytime cooling

Abstract Facile and efficient radiative daytime cooling technology is still a huge challenge. In this paper, we proposed an eco-friendly, facile, efficient superhydrophobic radiative daytime cooling film composed of polydimethylsiloxane, nano TiO2, and nano SiO2. This radiative daytime cooling film could have about 15°C cooling of Al sheet, 9°C cooling for the building model on a sunny summer day, and 8°C cooling for the building model on a cloudy summer day, respectively. This method is promising to be used in building cooling fields.

Microscale thermal variations in a walkable urban area during hot days: Analysis through mobile measurements and Day PET Signatures

This article analyzes the thermal variations of a small urban area recently transformed in the city center of Nantes, France, which has been designed to promote walkability and make it comfortable in summer. A measurement method based on mobile climate metrology, which offers high spatial resolution, was developed. Four measurements were conducted per day over five days between June and September 2023. The data was analyzed using the concept of the Day PET Signature (DPS), which reflects the dynamics of a point in space over the course of the day through variations in the Physiological Equivalent Temperature (PET) index. Four clusters of DPS were identified in the dataset, enabling the accurate assessment of the thermal diversity existing in the study area at different times of the day in summer. The results demonstrate that the observed differences between clusters are solely attributable to the radiative conditions at the distinct positions analyzed. The concept of a Radiative Portrait is introduced in order to characterize the thermal diversity of the study area. In contrast to the TMRT synthetic index, the Radiative Portrait provides a detailed breakdown of the fluxes, revealing the intensity of short- and long-wave radiation in top, bottom and lateral orientations. The combination of the Radiative Portrait and the PET class qualification provides a comprehensive understanding of the local climatescapes in summer.

ZnO/nZVI nanoparticle-enhanced double-slope U-shaped solar distillation: A thermodynamic investigation of cephalexin adsorption

The increasing need for sustainable methods to remove pharmaceutical contaminants like cephalexin and improve water desalination is critical. This study explores ZnO/nZVI nanoparticles synthesized with Jackfruit peel extracts as eco-friendly, cost-effective adsorbents, enhancing water purification in solar desalination systems. This work used a matte black paint coating within a double slope U-shaped solar distiller (DSUD) in a discontinuous experimental setting to examine potential improvements in solar distillation performance. Activated carbon (AC) and bioactive powdered nanoparticles of ZnO/nZVI (nano zerovalent iron), produced from jackfruit peel extracts (JP) were combined in a synergistic way. The effectiveness of cephalexin removal was assessed taking into account the JPAC solution parameters, reaction duration, ZnO/nZVI concentrations in the nanocomposite dosage, and initial nanocomposite concentration. The best conditions for cephalexin adsorption were found to be pH 5 and reaction time of 50 min, which resulted in high absorption efficiencies of 94.74% (nZVI) and 97.53% (ZnO) at room temperature with a JPAC dose of 2.50 g L⁻1. The efficiency of the eco-friendly adsorbent in getting rid of cephalexin was calculated using “pseudo-second-order kinetics” for nanocomposites, which is consistent with the “Langmuir” isothermal absorption process. The nanocomposites as absorbent materials in solar thermal desalination processes, efficient heat transmission and energy storage have been established. JPAC and the addition of steel balls (S) with a silver hue to the DSUD improved the internal heat transfer mechanisms. Thermodynamic of Gibbs free energy and the Laplacian method (TGL), two thermodynamic concepts, were used to extensively study the temperature dynamics of the DSUD with SJPAC components. For ZnO/JPAC, an exceptional distillate production rate was noted from 8:00 to 18:00, with a noteworthy 4.932 L/m2 output in winter and 5.833 L/m2 per day in summer. Using silver balls, ZnO/JPAC generated significant yields over a 24-h period: 8.957 L/m2 in summer and 7.253 L/m2 in winter, with an ideal energy efficiency of 51.05%. The unique advancements in TGL procedures and their environmental consequences are presented in this paper. The field of thermal energy transduction will advance if silver balls are used in DSUD for the synthesis of JPAC, ZnO/JPAC, and nZVI/JPAC, as supported by the theoretical insights presented here.