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Boiling is an effective energy-transfer process with substantial utility in energy applications. Boiling performance is described mainly by the heat-transfer coefficient (HTC) and critical heat flux (CHF). Recent efforts for the simultaneous enhancement of HTC and CHF have been limited by an intrinsic trade-off between them-HTC enhancement requires high nucleation-site density, which can increase bubble coalescence resulting in limited CHF enhancement. In this work, this trade-off is overcome by designing three-tier hierarchical structures. The bubble coalescence is minimized to enhance the CHF by defining nucleation sites with microcavities interspersed within hemi-wicking structures. Meanwhile, the reduced nucleation-site density is compensated for by incorporating nanostructures that promote evaporation for HTC enhancement. The hierarchical structures demonstrate the simultaneous enhancement of HTC and CHF up to 389% and 138%, respectively, compared to a smooth surface. This extreme boiling performance can lead to significant energy savings in a variety of boiling applications.

Vapor condensation is routinely used as an effective means of transferring heat or separating fluids. Dropwise condensation, where discrete droplets form on the condenser surface, offers a potential improvement in heat transfer of up to an order of magnitude compared to filmwise condensation, where a liquid film covers the surface. Low surface tension fluid condensates such as hydrocarbons pose a unique challenge since typical hydrophobic condenser coatings used to promote dropwise condensation of water often do not repel fluids with lower surface tensions. Recent work has shown that lubricant infused surfaces (LIS) can promote droplet formation of hydrocarbons. In this work, we confirm the effectiveness of LIS in promoting dropwise condensation by providing experimental measurements of heat transfer performance during hydrocarbon condensation on a LIS, which enhances heat transfer by ≈450% compared to an uncoated surface. We also explored improvement through removal of noncondensable gases and highlighted a failure mechanism whereby shedding droplets depleted the lubricant over time. Enhanced condensation heat transfer for low surface tension fluids on LIS presents the opportunity for significant energy savings in natural gas processing as well as improvements in thermal management, heating and cooling, and power generation.

Arachis hypogaea L. stems and leaves (AHSL) were used as raw materials, to extract phenolic acids through 60Co γ irradiation and solvent synergistic method. The extraction conditions were optimized by the response surface methodology of Box-Behnken, following a separation; thereafter, the antioxidant activity of the phenolic acid AHSL was studied. The results showed that the optimal extraction process could be achieved at an absorbed dose of 6.70 kGy and 70% ethanol concentration with 27∶1 liquid-solid ratio (mL∶g). The highest AHSL phenolic acid yield was (2.25±0.11)%. Among the process parameters, the absorbed dose showed the most significant effect on the AHSL phenolic acid yield (p=0.000 1).The phenolic acid content increased to 1.80 fold after extraction and purification with chloroform and ethyl acetate. Concerning the antioxidant activity, AHSL phenolic acid showed better free radical scavenging ability and ferric-reducing power than the ethanol extracts. Moreover, no significant difference could be observed in the hydroxyl radical scavenging effect between AHSL phenolic acid and tea polyphenols under the same concentration (p˃0.05). More than 50% of DPPH free radicals and hydroxyl free radicals could be removed at the AHSL phenolic acid concentration of 100 μg/mL. The results revealed that 60Co γ ray irradiation combined with ethanol extraction is feasible, and the phenolic acid from AHSL has strong antioxidant activity in vitro.

Background: In recent years,the lack of specific markers for the diagnosis of colorectal cancer has led to an upward trend in both morbidity and mortality from this condition. There is an urgent need to identify molecular biomarkers that contribute to early cancer detection. This study aimed to identify specific exosomal microRNAs that hold potential as diagnostic biomarkers for CRC. Methods: We screened for differentially expressed miRNAs using the CRC exosome dataset GSE39833. To validate the results in the public database, we collected serum from 168 CRC patients and 168 healthy volunteers. The expression levels of exosomal miR‐1470 in healthy volunteers and CRC patients were analyzed using qRT‐PCR. To evaluate the diagnostic potential of the selected miR‐1470 in distinguishing CRC patients from healthy controls, we analyzed its receiver operating characteristic curve. To explore the biological functions of miR‐1470 in CRC cell lines, we detected the miR‐1470's ability to regulate the growth and metastasis of CRC cells by CCK8, transwell and other assays after transfection of miR‐1470 in SW480, HCT‐116 cells. Results: Exosomal miR‐1470 exhibited significant up‐regulation in CRC patients compared to healthy volunteers. The ROC curve analysis revealed an area under the curve (AUC) of 0.74 (95% confidence interval: 0.6876–0.7920) for exosomal miR‐1470, indicating its potential as a diagnostic biomarker. Furthermore, the expression level of miR‐1470 in CRC patients showed correlations with age, metastasis, and HDL content. We overexpressed miR‐1470 in CRC cell lines. CCK8 proliferation assay showed that miR‐1470 promoted the proliferation ability of SW480 and HCT‐116 cells. Transwell assay showed that miR‐1470 promoted the migration and invasion ability of SW480 and HCT‐116 cells. Conclusion: This suggested that non‐invasive diagnosis of CRC is possible by detecting the level of miR‐1470 in exosomes, which has important implications for early detection and treatment of this disease. [ABSTRACT FROM AUTHOR]