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Radiative cooling passively removes heat from objects via emission of thermal radiation to cold space. Suitable radiative cooling materials absorb infrared light while they avoid solar heating by either reflecting or transmitting solar radiation, depending on the application. Here, we demonstrate a reflective radiative cooler and a transparent radiative cooler solely based on cellulose derivatives manufactured via electrospinning and casting, respectively. By modifying the microstructure of cellulose materials, we control the solar light interaction from highly reflective (> 90%, porous structure) to highly transparent (≈ 90%, homogenous structure). Both cellulose materials show high thermal emissivity and minimal solar absorption, making them suitable for daytime radiative cooling. Used as coatings on silicon samples exposed to sun light at daytime, the reflective and transparent cellulose coolers could passively reduce sample temperatures by up to 15 °C and 5 °C, respectively.

The smooth operation of the grate cooler is directly related to the energy efficiency of cement production, and the accurate control of its working condition is the key to improving the quality of cement and improving the cooling efficiency. In this paper, a method of classification and identification of grate coolers based on D-BIRCH is proposed. Firstly, by analyzing the whole cement firing process, grate pressure difference, raw feed amount, and kiln main motor flow were selected as the test parameters. Then, the D-BIRCH algorithm is used to obtain the operating condition label of each operating condition by clustering. Finally, the GBDT algorithm is used to train the condition label to get the corresponding condition recognition model. In this paper, the field operation data of a cement enterprise is selected for simulation, and the simulation results verify the feasibility of the proposed method.

In recent years, an increasing number of passive radiative cooling materials are proposed in the literature, with several examples relying on the use of silica (SiO2) due to its unique stability, non‐toxicity, and availability. Nonetheless, due to its bulk phonon‐polariton band, SiO2 presents a marked reflection peak within the atmospheric transparency window (8‐13 µm), leading to an emissivity decrease that poses a challenge to fulfilling the criteria for sub‐ambient passive radiative cooling. Thus, the latest developments in this field are devoted to the design of engineered SiO2 photonic structures, to increase the cooling potential of bulk SiO2 radiative coolers. This review seeks to identify the most effective photonic design and fabrication strategies for SiO2 radiative emitters by evaluating their cooling efficacy, as well as their scalability, providing an in‐depth analysis of the fundamental principles, structural models, and results (both numerical and experimental) of various types of SiO2 radiative coolers. Among several materials emerged for passive radiative cooling applications, SiO2 stands out due to its stability, abundance, recyclability, and overall safety. Patterning strategies of the SiO2‐air interface are reviewed, which can enhance its emissivity within the atmospheric transparency window (8–13 µm) by engineering its photon‐polariton band, opening new prospects in many application fields where SiO2 cover layers are routinely used.

To mitigate broadband casing noise of turbine coolers, the electric-vehicle acoustic-package paradigm is transposed and refined. A coupled FE model incorporating the full Johnson–Allard–Champoux (JCA) equivalent-fluid description quantifies the encapsulated vibro-acoustic response. Insertion-loss predictions are validated on a production cooler; measured and simulated levels deviate <0.8 dB across 125–8000 Hz. The validated framework offers a transferable low-noise design route for turbine machinery and broadens automotive acoustic-package strategies to thermos-fluid systems.

The high capacity intercooler of an ALCO V16 Marine Diesel Engine is modelled based on the original design in order to validate the working parameters and further, to improve the performances through an extended and complete simulation. The design and optimization of the intercooler will allow to replace the old equipment with a new solution, in order to increase the engine power and lower the pollutants.

All-day passive radiative cooling has recently attracted tremendous interest by reflecting sunlight and radiating heat to the ultracold outer space. While some progress has been made, it still remains big challenge in fabricating highly efficient and low-cost radiative coolers for all-day and all-climates. Herein, we report a hierarchically structured polymethyl methacrylate (PMMA) film with a micropore array combined with random nanopores for highly efficient day- and nighttime passive radiative cooling. This hierarchically porous array PMMA film exhibits sufficiently high solar reflectance (0.95) and superior longwave infrared thermal emittance (0.98) and realizes subambient cooling of ~8.2 °C during the night and ~6.0 °C to ~8.9 °C during midday with an average cooling power of ~85 W/m 2 under solar intensity of ~900 W/m 2 , and promisingly ~5.5 °C even under solar intensity of ~930 W/m 2 and relative humidity of ~64% in hot and moist climate. The micropores and nanopores in the polymer film play crucial roles in enhancing the solar reflectance and thermal emittance. There still remains a big challenge in fabricating highly efficient and low-cost radiative coolers for all-day and all-climates. Here, the authors report a hierarchically structured polymethyl methacrylate film with a micropore array combined with random nanopores for highly efficient day- and nighttime passive radiative cooling.

In view of the characteristic of large transformer load fluctuations, a feedforward fuzzy control strategy using the startup and shutdown of cooler groups as the executive means is proposed to meet the transformer temperature control requirements. Based on the research on the mechanism of oil-immersed forced oil circulation air-cooled (OFAF) coolers, fuzzy control rules are summarized to realize the closed-loop regulation of transformer oil temperature. Meanwhile, feedforward control is used to compensate for the impact of transformer power disturbances on oil temperature. A simulation control model of the OFAF cooler is built on the Simulink platform, which verifies the feasibility and effectiveness of the feedforward fuzzy control strategy for the transformer OFAF cooler. Furthermore, by comparing the results under two control execution modes, the advantages of using the startup and shutdown of cooler groups as the executive means are analyzed.

In recent decades, hundreds of glaciers draining the Antarctic Peninsula (63° to 70°S) have undergone systematic and progressive change. These changes are widely attributed to rapid increases in regional surface air temperature, but it is now clear that this cannot be the sole driver. Here, we identify a strong correspondence between mid-depth ocean temperatures and glacier-front changes along the ∼1000-kilometer western coastline. In the south, glaciers that terminate in warm Circumpolar Deep Water have undergone considerable retreat, whereas those in the far northwest, which terminate in cooler waters, have not. Furthermore, a mid-ocean warming since the 1990s in the south is coincident with widespread acceleration of glacier retreat. We conclude that changes in ocean-induced melting are the primary cause of retreat for glaciers in this region.

Radiative cooling is a well-researched area. For many years, surfaces relying on radiative cooling failed to exhibit a sub-ambient surface temperature under the sun because of the limited reflectance in the solar spectrum and the reduced absorptivity in the atmospheric window. The recent impressive developments in photonic nanoscience permitted to produce photonic structures exhibiting surface temperatures much below the ambient temperature. This paper aims to present and analyze the main recent achievements concerning daytime radiative cooling technologies. While the conventional radiative systems are briefly presented, the emphasis is given on the various photonic radiative structures and mainly the planar thin film radiators, metamaterials, 2 and 3D photonic structures, polymeric photonic technologies, and passive radiators under the form of a paint. The composition of each structure, as well as its experimental or simulated thermal performance, is reported in detail. The main limitations and constraints of the photonic radiative systems, the proposed technological solutions, and the prospects are presented and discussed.

Because of the generally lower activation energy associated with proton conduction in oxides compared to oxygen ion conduction, protonic ceramic fuel cells (PCFCs) should be able to operate at lower temperatures than solid oxide fuel cells (250° to 550°C versus ≥600 °C) on hydrogen and hydrocarbon fuels if fabrication challenges and suitable cathodes can be developed. We fabricated the complete sandwich structure of PCFCs directly from raw precursor oxides with only one moderate-temperature processing step through the use of sintering agents such as copper oxide. We also developed a proton-, oxygen-ion–, and electron-hole–conducting PCFC-compatible cathode material, BaCo0.4Fe0.4Zr0.1Y0.1O3-δ (BCFZY0.1), that greatly improved oxygen reduction reaction kinetics at intermediate to low temperatures. We demonstrated high performance from five different types of PCFC button cells without degradation after 1400 hours. Power densities as high as 455 milliwatts per square centimeter at 500°C on H2 and 142 milliwatts per square centimeter on CH4 were achieved, and operation was possible even at 350°C.