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• Pure, binary, and ternary refrigerants of 14 refrigerants are analyzed. • Different refrigeration systems are considered. • Pareto fronts of the COP and volumetric heating capacity are obtained. • Binary refrigerants have similar advantages to ternary refrigerants. Mixed refrigerants are widely used in heat pumps; thus, it is necessary to analyze the performance advantages of pure, binary and ternary refrigerants. In this paper, 14 kinds of pure refrigerants were selected, and 24,024 kinds of pure, binary and ternary refrigerants were obtained and analyzed. The refrigerant performance in terms of the COP and volumetric heating capacity were compared in normal, vapor injection with internal heat exchanger and with flash tank systems. In this paper, 40 °C was used as the temperature lift, and four cases with heating production temperatures of 70, 80, 90 and 100°C were analyzed. The Pareto fronts for the different refrigerant types and compositions were obtained by using exhaustive method. The COP and volumetric heating capacity exhibited contradictory trends in all cases. The results showed that mixed refrigerants had significant advantages over pure refrigerants in achieving the Pareto fronts. However, in all cases, when the COP was higher than 5, the binary refrigerants had similar advantages to ternary refrigerants; thus, ternary refrigerants were not necessary. When the COP was lower than 5, it was difficult to further increase the volumetric heating capacity by sacrificing the COP. [Display omitted] [ABSTRACT FROM AUTHOR]

A vapor compression cycle is a mechanical heat transfer device that moves heat from a lower-temperature sink to a higher-temperature sink. In vapor compression refrigeration, the condenser can remove heat from the system when it is hot and this heat can be rejected by air or water. The present work concentrates on an investigation that has been carried out experimentally of performance enhancement of a compression cycle with a shallow fluidized bed utilized to cool the condenser. The homogeneous particle size (0.5 mm) in the shallow fluidized bed helps to remove heat generated by the condenser; in order to guarantee adequate particle mixing, the surface of the bed kept approximately 2.5 cm high. The result shows that amount of coefficient of performance and power consumption of the compressor improvement ranges about 49.3 and 18.53%, respectively, by using the shallow fluidized bed for the condenser compared without condenser's shallow fluidized bed. Additionally, the condenser with a shallow fluidized bed obtained the best COP at an temperature of the evaporator of 8 °C, with an estimated value of 3.217. Moreover, when utilizing a shallow fluidized bed, the heat rejection ratio values reduced by about 35.7% when compared to the range of (H.R.R.) without a shallow fluidized bed. It is also observed that the amount of refrigerating effect values will improve when the condenser is immersed in the shallow fluidized bed ranges about 18.53% at times 60 min., compared without shallow fluidized bed for the condenser. [ABSTRACT FROM AUTHOR]

The current global warming challenges have drawn refrigerants with low Global Warming Potential (GWP). R32 (difluoromethane) is the most promising low-GWP refrigerant and is slightly flammable. The addition of a flame retardant to HFC-32 can improve its flammability. Trifluoroiodomethane (R13I1) is a flame retardant with an extremely low GWP that can be employed as a refrigerant component. This experimental study investigates the effect of dispersing aluminium oxide (Al2O3) nanoparticles in the compressor oil with varying concentrations of 0.045, 0.09, 0.135, and 0.18 vol% in the Polyol Ester (POE) oil on its thermal, tribological, and rheological properties as well as on the overall performance of a vapour compression air conditioning system using ultra-low GWP mixture refrigerants consisting of R32, R161, and R13I1 as the working fluid. The thermophysical properties of the mixture refrigerant have been calculated using REFPROP (NIST properties of fluid reference). The mixture refrigerant (R32/R161/R13I1) performed better in alumina nanolubricant and the comparison has been made with reference to the base lubricant (POE) in terms of power consumption, COP, coefficient of friction, and cooling capacity. The results showed that the coefficient of performance (COP) and cooling capacity increased by 32.6% and 11.7%, respectively. The maximum power saving is up to 16.1%, and the coefficient of friction is reduced by 32.4%. The highest recorded thermal conductivity reached 22.5% at 343.15 K and a volume concentration of 0.18%, compared to base oil at 303.15 K. The air conditioning system's performance showed improvement at an optimal concentration of 0.135 vol%. This study provides valuable insights into identifying energy-efficient and low-GWP refrigerant alternatives suitable for air conditioning systems. [ABSTRACT FROM AUTHOR]

Due to the increase in human population, there is an ever-increasing demand for energy in different sectors which leads to environmental problems like climate change, rise in temperature, and global catastrophes. Cooling systems have become a very essential element in recent decades for mankind. The present system focuses on the design and fabrication of a counter-flow humidification setup which uses biomass-based charcoal as the packing material. Air velocity and water flow rate have been varied along with the density of charcoal. Output parameters such as a change in pressure (ΔP), Coefficient of performance (COP), evaporation rate (ER), humidification efficiency (HE), specific cooling capacity (SCC), and energy consumption (EC) are evaluated. Performance parameters obtained for charcoal are compared with that of standard Celdek Packing. Through experiments, it is found that humidification efficiencies for Celdek and charcoal packing are 77.45% and 57.40% respectively. The overall coefficient of performance obtained is 1.41 for charcoal and 3.17 for Celdek packing. Among the three densities which were considered, charcoal packing with a density of 400 kg/m3 exhibited higher performance with respect to COP, HE, ER, and SCC. Similarly, a water flow rate of 0.4 lpm gave a maximum performance and 0.7 lpm gave the least. It is concluded that charcoal can be considered one of the highly efficient biomass-based materials contributing to sustainable energy related to cooling applications. [ABSTRACT FROM AUTHOR]

Water chiller is a crucial air conditioning unit in various industries, tasked with efficiently cooling large spaces. It utilizes two refrigerants, primary and secondary, during its cooling process. A well-functioning air conditioning system not only ensures human comfort but also benefits machinery and the overall environment. However, one significant issue leading to excessive electricity consumption is the mismatch between the refrigeration system's initial design and its real-world operation. To ensure energy efficiency, it's essential to evaluate the chiller's performance meticulously. To analyze the water chiller's performance, data was collected from its control panel over three days. This data includes water pressure and temperature both entering and exiting the evaporator, set point ampere, and compressor power. With this data, the actual Coefficient of Performance (COP) can be calculated and compared against the design COP. The research findings reveal that between January 23, 2023, and January 25, 2023, the chiller's actual COP falls below the design COP at 05:00, 08:00, 11:00, and 21:00. However, at 23:00, the actual COP surpasses the design COP. In conclusion, the water chiller demonstrates less efficient cooling during specific hours, resulting in heightened energy consumption. [ABSTRACT FROM AUTHOR]

Three-heat-reservoir (THR) heat pump has the originality of using low-grade heat to achieve pumping heat, and it can recycle waste heat and reduce environmental pollution effectively. Based on the research ideas of macro THR heat pumps and micro three-terminal thermoelectric devices, this paper proposes a THR thermal Brownian heat pump cycle model. This cycle is driven by low-grade “heat” to work, and it may be seen as a combined cycle consisting of a two-reservoir thermal Brownian heat pump and a two-reservoir thermal Brownian engine. Using non-equilibrium thermodynamics, expressions for heating load and coefficient of performance (COP) are derived. The coupling relation between external forces of two motors is obtained by solving the heat balance equations, and cycle performance is further obtained. The maximal heating load is obtained by optimizing barrier height, and the lower limit of COP is also given. Results show that the THR thermal Brownian heat pump can achieve pumping heat by using low-grade “heat”. The internal parameters affect the coupling between two-heat-reservoir thermal Brownian engine and two-heat-reservoir thermal Brownian heat pump, which determines cycle performance directly. The curve of heating load about COP presents a parabolic-like shape, and an optimal COP exists to maximize heating load.

Abstract Of the goals and targets specified by the Kunming‐Montreal Global Biodiversity Framework, Target 3, often referred to as “30 × 30,” has garnered widespread attention globally. In this paper, we critique India's potential to meet this target. We find that with its vast network of ecosystems that are under some form of protection and through the recognition of other effective area‐based conservation measures sites, India has the potential to meet the quantitative target of conserving and managing at least 30% of its area by 2030. However, the qualitative attributes of the target might be more difficult to realize owing to several challenges, such as inadequate landscape connectivity, insufficient representation of habitats in the current protected area model, and the exacerbation of socioeconomic vulnerabilities of resource‐dependent communities. To achieve strategic, inclusive, and equitable conservation, we suggest a four‐pronged approach involving landscape‐level biodiversity conservation, socially just and collaborative safeguarding of biodiversity, and relevant policy (re)formulation, informed and underlain by long‐term research and impact monitoring. Although we focus on India, the issues we discuss are of broader relevance, especially for countries across the Global South that are also likely to be significantly impacted by the implementation of the target.

IntroductionCenter of pressure (COP) parameters are frequently assessed to analyze movement disorders in humans and animals. Methodological discrepancies are a major concern when evaluating conflicting study results. This study aimed to assess the inter-observer reliability and test-retest reliability of body COP parameters including mediolateral and craniocaudal sway, total length, average speed and support surface in healthy dogs during quiet standing on a pressure plate. Additionally, it sought to determine the minimum number of trials and the shortest duration necessary for accurate COP assessment.Materials and methodsTwelve clinically healthy dogs underwent three repeated trials, which were analyzed by three independent observers to evaluate inter-observer reliability. Test-retest reliability was assessed across the three trials per dog, each lasting 20 seconds (s). Selected 20 s measurements were analyzed in six different ways: 1 × 20 s, 1 × 15 s, 2 × 10 s, 4 × 5 s, 10 × 2 s, and 20 × 1 s.ResultsResults demonstrated excellent inter-observer reliability (ICC ≥ 0.93) for all COP parameters. However, only 5 s, 10 s, and 15 s measurements achieved the reliability threshold (ICC ≥ 0.60) for all evaluated parameters.DiscussionThe shortest repeatable durations were obtained from either two 5 s measurements or a single 10 s measurement. Most importantly, statistically significant differences were observed between the different measurement durations, which underlines the need to standardize measurement times in COP analysis. The results of this study aid scientists in implementing standardized methods, thereby easing comparisons across studies and enhancing the reliability and validity of research findings in veterinary medicine.

This study explores the integration of parallel compression and a two-phase ejector in transcritical CO2 refrigeration systems, aiming to improve efficiency and performance. This innovative approach bridges the gap between conventional approaches and explores new energy-saving potential. The study uses thermodynamic modeling, mathematical simulation, and in-depth analysis to look at energy and exergy performance in a new configuration for applications in the retail sector at medium evaporation temperatures. The work investigates thermodynamic phenomena in a novel cycle with steady-state conditions, low pressure differentials, and adiabatic efficiency. The model is validated against experimental and theoretical published data, revealing component-specific exergy destruction and key parameters. The novel cycle efficiently extracts heat at higher temperatures, outperforming conventional and parallel cycles. Exergetic efficiency surpasses the standard cycle, with gas cooler pressure and temperature dependence enhancing efficiency by 40%–45%. The distribution of exergy destruction percentages reveals efficiency determinants, emphasizing heat exchange optimization and ejector responsiveness in energy dissipation dynamics. The study investigates the coefficient of performance (COP) dependence on gas cooler pressure and temperature, revealing superior performance compared to conventional cycles. COP increases by 50% at 80 bars, indicating enhanced efficiency. The new cycle offers exceptional efficiency gains, with a COP enhancement of over 75% for evaporator temperature transitions. Comparative analysis shows a COP superiority of up to 53% for lower evaporator temperatures and 20% for higher evaporator temperatures, demonstrating substantial energy savings and improved performance across various operating conditions.

Peltier modules control temperatures in niche products such as wine coolers and camping fridges or are used to precisely temper processes as for example the duplication of DNA sections. Accurate characterization and long term stability of the modules is crucial in order to meet the high reliability requirements especially in critical applications such as in space or medical technology markets. While most of the measurement stations are designed for thermoelectric generators, especially in regard to long term testing, the measurement of peltier modules is rarely described. In this contribution, we show a customized measuring station specifically for the combination of the characterization of peltier modules and their long term stability. With this measurement station, it is possible to determine temperature dependent properties such as the maximum current Imax, the maximum cooling power Image 1, the maximum temperature difference Image 2 and the coefficient of performance (COP) while performing cycling tests in between the characterization measurements. In this setup, both sides consist of water driven heat exchangers with a range of Image 3 to Image 4. The heat flow through the module is measured via two graphite heat flux meters.Thereby, it is possible to completely characterize a peltier module within this measuring system. An error analysis for the measured properties is given as well. In addition to the characterization of the modules, the long-term stability of the modules can be measured not only with static current and temperature but also at cyclical stimulation of temperature or current changes meaning that application-oriented long-term tests are possible.

In order to meet climate goals, it will be necessary to significantly reduce the greenhouse gases emitted by homes. A key factor in the US is to reduce the on-site combustion of fossil fuels for heating end-uses and to replace this with use of electric heat pump technologies connected to a low-carbon grid. The replacement of natural gas furnaces with electric heat pumps is a key home decarbonization strategy. However, the potential for space heating electrification to reduce greenhouse gas emissions depends on the carbon dioxide equivalent (CO2e) content of the electricity used by the heat pump. This varies considerably depending on the source of electricity, with large state to state variability. Furthermore, household energy costs are likely to be impacted by the electrification of space heating, because retail energy prices for both natural gas and electricity in each state vary by factors of seven and four, respectively. Contractors, energy programs, government and building code officials, as well as consumers need clear indications of the likely CO2e and energy cost impacts of proposed electrification projects, because these will affect decarbonization choices and rationales around scaled heating electrification. Government and utility programs also need to be aware of the likely outcomes of any supported/incentivized measures. In this paper, we investigate these effects by looking at new metrics to analyze the change in CO2e emitted and the cost to meet home heating loads when switching from a natural gas furnace to a heat pump for the contiguous 48 states of the mainland US.

Abstract Magnetic refrigeration utilizes the magnetocaloric effect of a magnetic material, whose temperature changes according to the change of magnetic field strength. It is regarded as an eco-friendly refrigeration technology in that it uses magnetic materials as refrigerants instead of CFC, HCFC, and HFC refrigerants used in vapor compression refrigeration. It is also regarded as an energy-efficient refrigeration technology in that it does not use noisy and power-consuming compressors. This paper presents thermodynamic analysis on a magnetic refrigeration system using experimental results obtained from a magnetic refrigeration apparatus. The magnetic refrigeration apparatus was built using two sets of concentric Halbach cylinders consisting of permanent magnet segments. Specifically the coefficient of performance (COP) of the magnetic refrigeration system was calculated using the energy removed from the working fluid across an AMR bed and the work input to run electric motors.

Cascade refrigeration systems are preferred in applications where low temperature cooling is required, such as in some special industrial and laboratory applications. Since, in these systems, the energy consumed by the compressors is less and the compressor outlet temperature is lower. Due to environmental problems, the use of natural refrigerants in cascade refrigeration systems has become to be of great importance. In this study, two cascade systems consisting of R744/R290 (System 1) and R1270/R290 (System 2) natural refrigerant pairs were designed and thermodynamically examined. In the analyzes performed according to different evaporator temperatures, the highest COP value was 3.66 at -20℃ evaporating temperature was obtained in the cascade system consisting of the R1270/R290 refrigerant pair. Moreover, it was considered that there was a 17.95% enhancement in exergy efficiency with the use of R1270 refrigerant in the low temperature cycle. By the rise in the evaporator temperature, energy consumption decreases and as a result, the amount of carbon dioxide emissions reduced was attained.

The objective of this study was to investigate the impact of solar radiation intensity on the performance of direct-expansion solar PVT heat pump systems. To this end, an experimental setup was constructed for direct-expansion photovoltaic (PVT) solar heat pump water heating systems and photovoltaic (PV) power generation systems. The system performance and main parameters were analyzed and discussed under different solar radiation intensities. The winter experiments in southern China revealed that the exhaust temperature of the heat pump unit varied considerably under clear conditions, while the back temperature remained stable, fluctuating between approximately −13.5 °C and 24 °C. In contrast, the power generation of PVT panels increased with the increase in radiation intensity, from 78.33 W to 122.68 W, for an increase of 56.6%. Furthermore, the total electricity generation of the PVT panels was higher than that of PV panels, with an increase of 8.7–8.3%. Nevertheless, discrepancies between experimental and theoretical data were observed, particularly under overcast conditions, where the back panel temperature error was pronounced. Additionally, the system exhibited enhanced stability at elevated temperatures in comparable environments, accompanied by an improvement in the system’s coefficient of performance (COP) by 5.67%.

Characterizing the optimal operating parameters for a heat pump with a specific refrigerant is paramount, as it provides valuable guidance for refrigerant selection. The temperature mismatch between cold and hot fluids in the evaporator and condenser can lead to degraded thermal performance in heat pumps with large temperature variations. To address these two key issues, we selected several pure refrigerants with varying critical temperature levels for use in a large temperature variation heat pump configuration. The corresponding thermal performance was then investigated using the Ebsilon code under fixed temperature lift conditions as the operating temperature varied. It indicates that the maximum coefficient of performance (COP) is typically achieved when the deviation factors of temperature and pressure from their critical parameters fall within the ranges of 0.62~0.71 and 0.36~0.5, respectively. Our research recommends the binary refrigerant mixture of R152a/R1336mzz(z) (COP = 3.54) for the current operating conditions, as it significantly improves thermal performance compared to pure R1336mzz (z) (COP = 2.87) and R152a (COP = 3.01). Through research on the impact of the compositional ratio of R152a/R1336mzz(z) on the thermal performance of the heat pump, we found that that the optimal ratio of R1336mzz(z) component to R152a component is 0.5/0.5. This study offers valuable guidance for selecting the most suitable refrigerants for heat pumps in practical engineering design scenarios.

At present, one of the main challenges that industry faces is its impact on global warming, linked to the greenhouse effect and ozone hole problems. These two environmental issues have not yet been solved completely and, concerning the industrial cold sector, countries are making various decisions on refrigerants. Magnetic refrigeration potentially represents a less impactful refrigeration technology. In this review, the physical basis of magnetic refrigeration is analysed, in order to propose this technology for industrial use.

Indirect evaporative coolers (IECs) use the latent heat of water evaporation to cool air. This system has the advantage of operating at low power without a compressor and does not increase the absolute humidity of the air. However, an IEC is difficult to use on its own because its cooling capacity is limited by the theoretical constraint of the wet-bulb temperature of the ambient air. Therefore, an air conditioning unit (ACU) was integrated with an IEC and experimentally evaluated in this study. The dry and wet channels of the IEC were integrated with an ACU evaporator and a condenser, unlike previous studies where IECs were integrated solely with either an evaporator or a condenser. This reduced the cooling load on the evaporator and helped the condenser to dissipate heat to improve the performance of the existing ACU. In addition, the IEC was equipped with baffles to improve its performance. To assess the extent of the performance improvement due to integration with the IEC, comparisons were also performed under the same experimental conditions with an ACU only. The results showed that under conditions with an indoor temperature of 32 °C, integrating the IEC with the ACU increased the average cooling capacity by 13.1% and decreased the average power consumption by 8.60% during the test period, compared to using only the ACU. Consequently, the average coefficient of performance (COP) increased by 19.5% compared to using only the ACU under the same conditions.

Drying agricultural produce consumes a considerable amount of energy. As an energy-efficient system, a heat pump can improve the energy efficiency of the drying process and hence reduce the energy consumption, especially in South Africa, where both sub-tropical and temperate weather conditions dominate. The objective of this research is to experimentally investigate the impacts of weather conditions on the operational conditions and thermal performance of an open-loop air-source heat pump drying system. The experimental investigation was conducted in a climate chamber where the climate conditions were simulated from −10 °C to 20 °C with an interval of 10 °C for the typical temperature range of the harvesting season in South Africa. The findings indicate that ambient temperatures have a significant impact on both the operating conditions and thermal performance of an open-loop heat pump system; the change in ambient temperatures from −10 °C to 20 °C leads to a 141.6% improvement in the suction pressure, a 214.2% increase in the discharge pressure, and 30.1% increase in the compression ratio, as well as a consequent increase of 130.6% in the refrigerant mass flow rate (from 0.0067 to 0.0155 kg/s), resulting in a corresponding increase in the coefficient of performance (COP) of the heat pump drying system by about 42.1%. Therefore, this study suggests that, while using an open-loop air-source heat pump drying system utilising R134a refrigerant is feasible in South Africa, it may be practically limited to regions with warm climates or during warmer seasons.

Measuring postural control in an upright standing position is the standard method. However, this diagnostic method has floor or ceiling effects and its implementation is only possible to a limited extent. Assessing postural control directly on the trunk in a sitting position and consideration of the results in the spectrum in conjunction with an AI-supported evaluation could represent an alternative diagnostic method quantifying neuromuscular control. In a prospective cross-sectional study, 188 subjects aged between 18 and 60 years were recruited and divided into two groups: “LowBackPain” vs. “Healthy”. Subsequently, measurements of postural control in a seated position were carried out for 60 s using a modified balance board. A spectrum per trail was calculated using the measured CoP tracks in the range from 0.01 to 10 Hz. Various algorithms for data classification and prediction of these classes were tested for the parameter combination with the highest proven static influence on the parameter pain. The best results were found in a frequency spectrum of 0.001 Hz and greater than 1 Hz. After transforming the track from the time domain to the image domain for representation as power density, the influence of pain was highly significant (effect size 0.9). The link between pain and gender (p = 0.015) and pain and height (p = 0.012) also demonstrated significant results. The assessment of postural control in a seated position allows differentiation between “LowBackPain” and “Healthy” subjects. Using the AI algorithm of neural networks, the data set can be correctly differentiated into “LowBackPain” and “Healthy” with a probability of 81%.

Thermoelectric air condition system (TEACs) powered by solar photovoltaics is useful for thermal comfort applications, especially when there is a direct energy source like sunlight. This paper presents experimental investigations of solar-powered thermoelectric air conditioning for both cooling and heating modes. The experiments were carried out in a test room whose volume is 1 m3 under the climatic conditions of the city of Baghdad. In the summer, the thermoelectric device functions as a Peltier cooler. The cold side absorbs the heat from the inside to lower the room's temperature. As for winter, the heat is released from the thermoelectric Peltier module by reversing the current applied to the thermoelectric Peltier to raise the room's temperature. In this work, the thermoelectric air condition system was supplied with different electrical power supply values with time intervals between the ON/OFF operations. The results showed that the system could heat and cool the air well in different operation conditions. The lowest temperature (22°C) is achieved in the cooling mode, with a Coefficient of Performance (COP) of 0.64 and an exergy efficiency of 0.47. In contrast, in the heating mode, the highest temperature is (31°C) with a COP of 0.87 and exergy efficiency of 0.75. This simple and eco-friendly method can minimize the cooling and heating load in the room.

Abstract The objective of this study is to analyze a combined cooling and power system from both exergy and economic perspectives, taking into account low-, medium-, and high-pressure steams. The system configuration consists of various components, namely the boiler, tank, turbine, generator, unit referred to as 180, absorption chiller, and separator. The high- and medium-pressure steams are utilized to generate power in the chiller turbine. Additionally, the low-pressure steam, which is discharged from the turbines and recycled from different sections of the system, is used to provide heat for the absorption chillers and cool the water used in the production line, thereby reducing the capacity requirements of the wet cooling towers. Among the available options, the turbine with a cost of 300 €/kW proves to be the most suitable choice for the proposed system. The results indicate that increasing the generator temperature from 65 °C to 90 °C leads to an increase in the coefficient of performance (COP) from 0.67 to 0.77. Moreover, the COP, power production, turbine efficiency, and total exergy efficiency of the proposed system are determined as 0.73, 5000 kW, 16,876 kW, 35.98%, and 57%, respectively. Ultimately, by implementing the proposed system, the product's production has been enhanced by 7% while generating an additional 16 MW of power, which represents a significant capacity for the Kurdistan Petrochemical Complex.

Objective: This study aimed to optimize the performance of heat pump system and discuss the optimal exhaust pressure of carbon dioxide system under the control of different working conditions. Methods: By establishing a CO2 trans-critical heat pump model, the relationship between exhaust pressure and heat production, inspiratory superheat, refrigerant mass flow rate and system energy efficiency was analyzed, and the influence of inlet and outlet water temperature and ambient temperature on the optimal exhaust pressure was deeply studied. Moreover, the reliability of the model was verified by the CO2 heat pump test bench. Results: At the three effluent temperatures, the heat production increased with the increase of exhaust pressure, and the mass flow rate decreased with the increase of exhaust pressure. The cycle performance coefficient and superheat showed a trend of first increasing and then decreasing with the increase of exhaust pressure, the optimal exhaust pressure increased with the increase of inlet and outlet water temperature and ambient temperature, but the increase of inlet and outlet water temperature reduced the system cycle performance coefficient. Based on this, the optimal exhaust pressure correlation formula at the outlet temperature of 60 ℃ was fitted, and five groups of tests were designed to prove its reliability. Conclusion: The optimal exhaust pressure of the system is determined by a large number of simulation data, and compared with the test values, it is found that the error values are less than 5%, which meets the test and design requirements.

Cooling refrigeration systems ingest prime energy and contribute to universal negative impact due to ecologically unfavorable working fluids used. Hence, the quest to improve the performance of Vapour Compression Refrigeration System (VCRS) with more efficient and eco-friendly refrigerant such as nanoparticles becomes imperative. In this study, performance analysis of hybrid nanofluids-zeotropic mixtures in a VCRS were experimentally investigated to determine the best operating optimum performance using exergy based approach. To achieve this, varying concentrated mixtures were selected using ternary graph. The results revealed that all the designated ratios of the mixed refrigerant with different fractions achieved good performance improvement with optimum values obtained at (011) zero gram of TiO2, 7.5g-Al2O3/CuO. All the selected hybrid mixtures led to an improved outcome in terms of Coefficient of Performance (COP), less power consumption and high performance exergetic efficiency, with COP values ranging from 0.31% to 3.10% and exergetic efficiency from 0.32 to 1.43%. The value for thermal conductivity, dynamic viscosity, density and specific heat were found to be highest (0.0958 W/m.K; 0.00164 W/m.K; 686.82 kg/m3 and 359.82 kJ/kg.K) at the same concentration of zero grams TiO2 in the mixture. Comparison made from the performance characteristics curve (with global parameters) indicated that maximum power coefficient and cooling capacity for the various concentrations were found at (001) 7.5g-TiO2, zero grams Al2O3/CuO equal to 2.2 kW, and the minimum value at concentration of 5 was 0.61% at (111) 5g-TiO2/Al2O3/CuO, and 0.87% for (121). An increase was observed in the maximum power coefficient, cooling capacity and COP increased by 13.51%, 5.78% and 10.33%. It was also observed that hybrid nanofluid-zeotropic refrigerant worked seamlessly with VRCS, making it a sustainable, green and clean as well as eco-friendly alternative with near-zero to zero negative effects on public health safety and environment.

Abstract Background Miniature Dachshunds have a high prevalence of neurological and musculoskeletal diseases potentially affecting their balance. The postural stability of dogs in quiet standing is an indicator of postural control and can aid in diagnosing and monitoring lameness and other pathologies affecting balance. Measures of centre of pressure (CoP) can be obtained from force and pressure platform systems to evaluate postural stability, however the two systems have not been compared and the latter has not been validated in dogs. The aims of this study were to assess the validity and reliability of using a pressure mat compared to a force platform and report normative values of CoP measures in healthy miniature Dachshunds. Forty two healthy miniature Dachshunds of smooth, long and wire-haired breed types stood still on a pressure mat (Tekscan MatScan®) placed on a force platform and the two systems were synchronised. Maximum anterior-posterior (AP) and medial-lateral (ML) ranges, sway path and 95% area of a best-fit ellipse were computed. Bland-Altman plots and coefficients of correlation assessed validity; intra-class correlation coefficients (ICC) assessed inter-test reliability for both systems. Non-linear regression analyses were used to describe the relationship between CoP and demographic measures. Results Strong correlations for AP range, ML range and 95% ellipse area and moderate correlation for sway path were found between the two devices. ICC showed good reliability (0.75–0.90) for AP range and moderate (0.5–0.75) for ML range and the 95% ellipse area for both devices. Sway path reliability was excellent (> 0.90) with the force platform but moderate with the pressure mat. Age was positively correlated with balance (inversely correlated with all measures except sway path), while weight explained 94% (force platform) and 27% (pressure mat) of the variance in sway path. Conclusions Pressure mats can be used to obtain valid and reliable measures of CoP and replace use of force platforms. Older (non-senior) and heavier (non-obese) dogs show better postural stability. Clinical examinations should include the use of a range of CoP measures when assessing postural balance, while accounting for the effects of age and body weight.

Soybean can serve as an efficient carbon and nitrogen source for in-situ fabrication of efficient composite electrocatalysts with conductive nitrogen-doped carbon (N-C) material. In this study, the iron-doped cobalt nitride/phosphide (Fe-Co3N/CoP) nanosheet was composited with a conductive N-C material by using soybean as C and N source, as well as NH3 as additional nitrogen source. During the nitridation process of Fe-Co3N, N-C bond was formed as a newly generated Co(Fe)-N-C active sites. Therefore, it fabricates a good microscopic contact interface between the catalyst and carbon material for charge transfer. Besides, the introduction of Fe-CoP by partially phosphating Fe-Co3N further improved the OER activity due to the high catalytic activity of Co sites with high valence state. As a result, the obtained electrocatalyst exhibited overpotentials as low as 285 and 390 mV for supporting 10 and 100 mA/cm−2 current densities. This work indicates that the design of materials with good interfaces could be an effective approach for the preparation of electrocatalysts for water electrolysis.

Fashion Industry Charter for Climate Action is consequence of a long-term international meeting chain, called the COP-Conference of Parties. The COP is an international climate conference that unites the signatory countries (195 countries + the European Union) of the United Nations Framework Convention on Climate Change (UNFCCC) since 1995. The goal of the consecutive meeting chain is to manage the interiorization of the Convention and negotiate new commitments. Fashion Industry Charter for Climate Action is prepared and launched by the patronage of UN Climate Change at COP24 in Katowice, Poland, in December 2018 and renewed at COP26 in Glasgow, UK, in November 2021. The stakeholder of the charter is the global fashion stakeholders including textile, apparel and clothing industries with a holistic commitment. The charter contains the vision to achieve net zero emissions by 2050 in line with keeping global warming below 1.5°C from pre-industrial levels defined in the COP 21 of Paris Agreement in 2015. In line with the launched charter, planned tasks of global fashion industry are focused on decarbonisation, reduction of greenhouse gas emission (GHG), renewable electricity utilization across supply chains, implementation of tools and measures about broadening climate actions. Therefore, the paper is aimed to inform and increase the awareness about current climate actions of global fashion industry.

The energy efficiency of the single-effect absorption refrigeration systems (ARS) using ionic liquid (IL) [Emim]Br as an absorbent and water as a refrigerant is evaluated in this study. The thermodynamic properties of the mixture, such as vapor pressures and excess enthalpies, are calculated using the non-random two-liquid (NRTL) activity coefficient model. The coefficient of performance (COP) is estimated with fixed temperatures for the evaporator, absorber, condenser, and generator, set at 10, 30, 40, and 100 °C, respectively. It is found that the COP of the single-effect ARS using [Emim]Br-H2O as the working pair is about 0.8, which is slightly lower than that obtained with LiBr-H2O (0.83), but much higher than that of H2O-NH3 (0.65) systems. The effect of generator temperature on COP has the same trend as that of other IL working pairs. The influence of each component temperature on the system’s performance is investigated, and it is found that the single-effect ARS performs very well under different conditions with [Emim]Br - H2O as the working pair.

Metal-organic frameworks (MOFs), with biocompatible and bio-friendly properties, exhibit intriguing potential for the drug delivery system and imaging-guided synergistic cancer theranostics. Even though tremendous attention has been attracted on MOFs-based therapeutics, which play a crucial role in therapeutic drugs, gene, and biomedical agents delivery of cancer therapy, they are often explored as simple nanocarriers without further “intelligent” functions. Herein, Fe-doped MOFs with CoP nanoparticles loading were rationally designed and synthesized for photothermal enhanced reactive oxygen species (ROS)-mediated treatment. Fe-ZIFs@CoP could generate efficient ROS through the Fenton reaction while depleting glutathione for amplifying oxidative stress. Particularly, due to the photothermal effect of Fe-ZIFs@CoP, the hyperthermia generated by as-synthesized Fe-ZIFs@CoP facilitated the advanced performance of the Fenton effect for a high amount of ROS generation. The promising “all-in-one” synergistic MOFs platform herein reported provides some prospects for future directions in this area.

AbstractThis study proposes a new active direct evaporative cooling system that uses a bundle of cotton fibers as an evaporating surface and activated carbon as a moisture adsorbent. A two-stage evaporative cooling experimental setup consisting of an activated carbon adsorbent in between the cooling pad was designed, fabricated, and tested at Bahir Dar, Ethiopia. The fiber bundle (pad 1) was wetted with water and ambient air was forced through it using a fan then the air that exiting from pad 1 was forced through a bulk of activated carbon (moisture adsorbent), and then the air from the adsorbent passed through the second wetted fiber bundle (pad 2). The energy source for the fan and pump was the solar photovoltaic energy system. The average temperature drop of the cooler without the moisture adsorber was 9.33°C and with the inclusion of the moisture, the adsorber gave an additional temperature drop of 1.5°C to 4.95°C. During the hot dry season, the average relative humidity of the ambient air, pad 1 outlet, adsorbent outlet, and pad 2 outlets were 28.26%, 76.12%, 55%, and 88.2% respectively. The cooler with moisture adsorbent had a cooling capacity of 3653 W, an effectiveness of 94.25%, and a COP of 52.2. The developed solar evaporative cooling system can provide energy-efficient, sustainable, affordable cold air for different applications. The cooler could be used by small-scale farmers, wholesalers, and retailers for the cooling and storage of horticultural products to reduce the postharvest loss in fresh produces.

Addressing the large carbon footprint of conferences such as the UN Climate Change Convention Conference of the Parties (COP) will be important for maintaining public confidence in climate policy. Transparency is also a vital aspect of creating equitable outcomes in climate policies, as often those most likely to be affected or who are able to create change on the ground are often unable to attend in person because of the high financial costs as well as having a large carbon footprint. The selection of host locations for the regular meetings of the UN Climate Change Convention is based on a rotation in amongst the five UN regions, which for 2022 is Africa. Here, we present UCL’s own carbon footprint calculator and use it to weigh the benefits of certain modes of transport to the 2021 COP 26 in Glasgow, UK and the 2022 COP 27 to be held in Sharm El-Sheikh, Egypt. The calculator demonstrates the well-known carbon-efficiency of coach and rail over flights, but shows that these benefits are only partly mitigated in the case of COP 27 due to insufficient transport links from Europe to the conference location. However, we also highlight some of the benefits of hosting a COP in the global South, particularly in the context of climate justice. Incorporating these principles into the calculator, we invite visitors to COP this year to carefully consider their options for carbon offsetting and how the tenets of climate justice could be integrated into the carbon accounting framework.

[Display omitted] • The close contact between Co and CoP at the interface results in the formation of space-charge region. • The existence of space-charge region promotes the rapid transfer of electrons from Co to CoP. • Co active sites with increased electron density enhance the adsorption and activation ability of CO 2. • The high-speed reduction of CO 2 was realized by reducing the activation energy barriers. Photocatalytic CO 2 reduction has been regarded as an ideal method to simulate photosynthesis for achieving carbon neutralization. However, poor charge transfer efficiency limits its development. Herein, an efficient Co/CoP@C catalyst was prepared with compact contact of Co and CoP layer by using MOF as precursor. At the interface of Co/CoP, the difference in functionality between the two phases may result in uneven distribution of electrons, thus forming a self-driven space-chare region. In this region, spontaneous electron transfer is guaranteed, thus facilitating the effective separation of photogenerated carriers as well as boosting the utilization of solar energy. Furthermore, the electron density of active site Co in CoP is increased and more active sites are exposed, which promotes the adsorption and activation of CO 2 molecules. Together with suitable redox potential, low energy barrier for *COOH formation and easy desorption of CO, the reduction rate of CO 2 catalyzed by Co/CoP@C is 4 times higher than that of CoP@C. [ABSTRACT FROM AUTHOR]