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Traditional embossing processes applied to papers generate significant amounts of heat, leading to the degradation and decreased efficiency of the rubber cylinder, a critical component of the machine, over time. This study investigates a novel internal cooling system designed to address this issue and extend the lifespan of the rubber cylinder. Experiments were conducted using tap water and ethylene glycol aqueous solution as coolants at a machine speed of 350 m/min and a specified pattern density. The results suggests that the non-cooled cylinder started to deteriorate at a surface temperature of approximately 46 °C. However, with the implemented cooling system, the surface temperature was effectively maintained at 4-5 °C below this threshold, significantly extending the operational life of the rubber cylinder. Therefore, this study emphasizes the effectiveness of internal cooling in mitigating heat-induced damage and extending the lifespan of embossing cylinders. [ABSTRACT FROM AUTHOR]

[Display omitted] Energy consumption from air cooling systems in summer, water scarcity in hot regions, and the functional reusability of waste paper are emerging environmental problems. Finding solutions to these problems simultaneously remains a significant challenge. Herein, a superhydrophobic passive cooling Cellulose-CaCO 3 film with hierarchical nano-sheets was fabricated to realize daytime radiative cooling with a temperature drop of 15–20 °C in summer and water harvesting with harvesting efficiency of 387 mg cm−2h−1 bd utilization of recycled waste paper. The superhydrophobic Cellulose-CaCO 3 film demonstrates its self-cleaning properties against inorganic and organic pollutants. Furthermore, the superhydrophobicity of the film was maintained after base/acid corrosions, dynamic water flushing, and thermal treatment at 100 °C for 7 h, exhibiting good durability of the superhydrophobicity. Moreover, the superhydrophobic Cellulose-CaCO 3 film is nonflammable after exposure to fire combustion for 1 min. In addition to waste paper, waste maize straws, and pasteboards were also collected to produce superhydrophobic passive cooling films. Results indicate that the above three cellulose-based raw materials can be well used to prepare durable superhydrophobic passive cooling materials. Environmental toxicology assessments confirm the safety of the material. This study not only provides a protocol for preparing superhydrophobic materials; but also demonstrates their potential for passive cooling and water harvesting. [ABSTRACT FROM AUTHOR]

Many materials have been explored for the purpose of creating structures with high radiative cooling potential, such as nanocellulose-based structures and nanoparticle-based coatings, which have been reported with environmentally friendly attributes and high solar reflectance in current literature. They each have their own advantages and disadvantages in practice. It is worth noting that nanocellulose-based structures have an absorption peak in the UV wavelengths, which results in a lower total solar reflectance and, consequently, reduce radiative cooling capabilities. However, the interwoven-fiber structure of cellulose gives high mechanical strength, which promotes its application in different scenarios. The application of nanoplatelet-based coatings is limited due to the need for high volume of nanoparticles to reach their signature high solar reflectance. This requirement weakens the polymer matrix and results in more brittle structures. This work proposes a dual-layer system, comprising of a cellulose-based substrate as the bottom layer and a thin nanoparticle-based radiative cooling paint as the top layer, where both radiative cooling potential and mechanical strength can be maximized. Experimental and theoretical studies are conducted to investigate the relationship between thickness and reflectance in the top coating layer with a consistent thickness of the bottom layer. The saturation point is identified in this relationship and used to determine the optimal thickness for the top-layer to maximize material use efficiency. With the use of cotton paper painted with a 125 μm BaSO4-based layer, the cooling performance is enhanced to be 149.6 W/m2 achieved by the improved total solar reflectance from 80 % to 93 %. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate influence of calcination and cooling conditions on pozzolanic reactivity of waste paper sludge. Calcined paper sludge (CPS) is prepared by different temperatures of calcination, duration of calcination and cooling methods. Pozzolanic activity of CPS was investigated by using API (Assessed Pozzolanic Activity Index) and SAI (Strength Activity Index) in accordance with ASTM C618 -17 (KS L 5405) and consumption of Ca(OH) 2 hydrate in mortars with CPS in detail, and compared to that of commercial fly ash (FA) and blast furnace slag (BFS) used in the concrete industry. Results revealed CPS produced from waste paper sludge had excellent pozzolanic activity compared with commercial pozzolanic admixtures such as FA or BFS. Their pozzolanic activity was most excellent in calcination temperature of 700 °C, calcination duration of 2 h and cooling method of water quenching. SAI (%) of mortar with CPS produced under optimal conditions was 96% at 28 days of age, and satisfied the quality of fly ash (Class F) as specified in ASTM C618 -17 (KS L 5405). There was linear relation between API (%) and SAI (%) of mortars with CPS, and the correlation coefficient was relatively good as 0.8 at 28 days of age. The API method is recommended as rapid and appropriate evaluation of the pozzolanic activity of the CPS. [ABSTRACT FROM AUTHOR]

This short report added to the scientific debate regarding a controversial conclusion published in European Journal of Sport Science. Reasons for the conflicting views have been presented in detail. Importantly, updated evidence suggests that ingestion of ice slurry is an effective countermeasure for endurance performance in the heat. Endurance athletes competing in the upcoming Tokyo 2020 Summer Olympics are encouraged to continue utilizing this simple yet very effective method for best possible performance.

Large power transformers using perfluorocarbon liquid have advantages of high dielectric strength, excellent cooling ability, and nonflammability. To make the transformer more compact, it is very important to improve the insulation material. Recently, the authors succeeded in developing a new type of aramid insulation paper which has no fluff on its surface to avoid field concentration. In this study, an outline of the developed paper and the experimental results of the insulation strength on turn-to-turn and intercoil models are described. It was found that the new aramid paper increases the insulation strength 1.2 (turn-to-case) to 1.7 (intercoil case) times that of the existing insulating paper. [ABSTRACT FROM AUTHOR]

Among various factors influencing the service life of electrical equipment, the performance of dielectric insulation materials has an important role. Degradation of insulating materials caused by aging is fatal to insulation breakdown. The dielectric sheets of most conventional and high-temperature superconducting electrical equipment are working at tensile status when lapped on the conductor. Therefore, the study of the dielectric characteristic for insulation materials at aging and tensile status is very important to safely operate electrical equipment. In this paper, a special electrode system was designed to measure the breakdown voltages of polypropylene laminated paper, polyimide, and polytetrafluoroethylene sheets at tensile status both in normal environment and liquid nitrogen. Before the breakdown experiment, the specimens of the three materials all endured the aging process of abrupt temperature change. According to the test results and the Weibull plot analysis, the polyimide presents good dielectric strength at aging and tensile status both in normal environment and in liquid nitrogen. [ABSTRACT FROM PUBLISHER]

Oil soluble chemical markers such as methanol, ethanol and 2-furaldehyde for assessing the condition of insulating paper still present many challenges for an accurate interpretation in real transformers. Indeed, many conceptual parameters such as design (shell vs. core) or type of cooling are needed for a more accurate interpretation of the data. Moreover, similarly to water, the measured marker concentrations in oil are temperature-dependent, i.e. an existing partition phenomenon between the oil and the solid insulation modify the solubility of the markers, thus changing their apparent concentrations in the oil. Consequently, to follow the real trend of these species during the transformer?s service life, it is crucial to correct their concentrations at a specific temperature, as is done for the water content. Knowing these facts and in order to calibrate a predictive model, Hydro-Qu?bec decided to access equipment when dismantled, which enables a large amount of paper to be sampled from different sections of the windings. This allows for a more accurate representation of the transformer paper conditions in relation to transformer design. The paper condition obtained by measuring the degree of polymerization in accordance with the presence of chemical markers is a valuable process. We believe that it is possible to better understand the behavior of the paper insulation and to assess markers concentration thresholds using the oil analysis. This article discusses the recent experience in this field with specific cases. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to evaluate the performances of cellulosic pads made out of Kraft and NSSC corrugated papers in three flute sizes, experimentally. A number of experiments have been done in a wind tunnel in order to evaluate the cooling efficiency and water consumption as a function of air velocity. The tests were carried out at three levels of air velocity (1.8, 2.25, and 2.67ms−1) for three flute sizes of Kraft and NSSC corrugated papers (2.5, 3.5, and 4.5mm). Analysis of the results indicated that cooling efficiency improves with decrease of air velocity and flute size of corrugated papers; however, water consumption increases with the increase of air velocity. The results were compared with each other and it was shown that the cellulosic pad made out of Kraft paper with 2.5mm flute size has the highest performance (92%) at 1.8ms−1 air velocity in comparison with the other cellulosic pads. [Copyright &y& Elsevier]

Subject to an autonomous underwater vehicle (AUV) with rigorously limited space and weight, the high-power-density propulsion motor urgently needs an efficient cooling method to improve reliability and stability. In this paper, a cooling improvement method based on heat bridges (HBs) is proposed for the shell-mounted propulsion motor (SmPM) of the AUVs. First, the electromagnetic and thermal characteristics of a 150 kW SmPM are analyzed using a numerical method. Then, a prototype was developed and tested to verify the accuracy of the numerical calculation. Subsequently, in order to further improve the cooling performance of the motor with minimal weight increment, this paper proposes HBs mounted on the end winding. The maximum winding temperature of the motor containing the proposed HBs is decreased by 20 K at the rated operation state. Based on the validated numerical method, the effects of topologies, materials, and geometric parameters on the cooling effect are investigated. Furthermore, according to the required operating time, the SmPM is optimized based on the cooling performance improvement provided by the proposed HBs. The results show that in addition to the benefit of the cooling improvement contributed by the proposed HB, the weight of the propulsion motor is reduced by 7.14%. [ABSTRACT FROM AUTHOR]

Abstract: To date, the most successful and popular vitrification method is based on the minimum volume cooling (MVC) concept, in which embryos are vitrified in a very small volume of vitrification solution (VS) and then stored in cryotubes in liquid nitrogen (LN2). Unfortunately, these methods need special devices and may not be suitable for vitrifying a large number of embryos. Theoretically, more embryos in VS on a paper (MVC concept) in cryotubes can be vitrified effectively. Therefore, this study directly vitrifies mouse embryos on a Kimwipes tissue in an 1.8mL cryotube. The ICR 2-celled to blastocyst embryos were used for testing this procedure. In Treatment 1, embryos transferred with 1–2μL of VS into a cryotube. Treatment 2 was similar to Treatment 1 except that the cryotube was filled with LN2. Treatment 3 was identical to Treatment 1 except that a small piece (5mm2) of a sterilized Kimwipes tissue was placed on the top of VS. Treatment 4 was identical to Treatment 3 except for the cryotube being filled with LN2. After each treatment, the cryotubes were capped and transferred to a LN2 tank. After warming, the recovered embryos were cultured in KSOM+AA for 1–3days. There were no differences in the recovery rate, overnight survival rate, blastocyst rate, and birth rate after embryo transfer among all treatment groups. Our results demonstrated an alternative simple, efficient, and mass reproducible method for vitrifying mouse embryos using papers as a vehicle and cryotubes as a container. [Copyright &y& Elsevier]