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Alternative refrigerants for R410A, which is most commonly used in building cooling and heating, are being requested with a global warming potential of 750 or lower and these regulations will continue to be implemented. At the current stage, several candidates are being discussed, but these will not be the final solution. What is certain is the R410A replacement refrigerant will be proposed in the form of mixed refrigerants. To figure out the thermodynamic properties of the mixed refrigerant, VLE data must be obtained first. In this study, we performed VLE experiments on a representative mixed refrigerant (R32-R125) to verify our newly constructed VLE experiment facility, and compared the results with the REFPROP 10 and the results of other researchers. The experiment was conducted at a temperature of 273.15 K to 313.15 K, and the maximum MAPE for pressure was found to be 0.0178 % and the maximum MAE for composition was found to be 0.0029. In the future, the facility will be used to present VLE test data with new mixed refrigerants as candidate replacement refrigerants for R410A. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oxygen-deficient TiO 2-x NPs are prepared by one-pot ultrasonic spray pyrolysis. • The one-pot synthesis mechanism for NPs with bulk defects is specifically proposed. • High-concentration bulk defects demonstrate to promote photo-to-heat conversion. • Black TiO 2-x shows good an evaporation rate of 2.12 kg m-2h−1 due to bulk defects. • The higher evaporation rate is achieved in black TiO 2-x compared to carbon black. While black TiO 2-x nanoparticles (NPs) have emerged as promising photothermal materials due to exceptional light absorption properties and intrinsic stability for reliable interfacial water evaporation (IWE) system, their lower evaporation rate (0.8–1.53 kg m-2h−1) than carbon materials remains a significant challenge. This poor evaporation rate is attributed to the low photo-to-heat conversion property of black TiO 2-x nanoparticles with a microstructure containing oxygen vacancies exclusively in the surface region—a consequence of the common reduction-based synthesis process. Herein, we achieved an outstanding evaporation rate of 2.12 kg m-2h−1, significantly higher than previous results under 1sun illumination due to the high-concentration bulk oxygen vacancies that promote the photo-to-heat conversion of black TiO 2-x nanoparticles. Moreover, it demonstrated that black TiO 2-x NPs exhibited a higher evaporation rate than carbon black, a typical carbonaceous photothermal material, under identical conditions. Furthermore, an innovative synthesis method utilizing the ultrasonic spray pyrolysis (USP) process and synthesis mechanism is proposed to introduce high-concentration bulk oxygen vacancies. This method overcomes the unavoidable drawbacks of conventional reduction-based synthesis methods, including surface-concentrated oxygen vacancies of the black TiO 2-x. This work provides valuable insights into the defect engineering of metal oxides for high-performance photothermal materials. [ABSTRACT FROM AUTHOR]

We studied the anion clusters of anthracene, An[SUP-,SUBN] (n = 1-16), by mass spectrometry, photoelectron spectroscopy, and theoretical calculations. The magic numbers observed at n = 5 and 13 indicated formation of the half-filled and completely-filled first solvation shell, respectively. We found that autodetachment could occur via a short-lived excited state of the anion, producing autodetached electrons at a nearly constant kinetic energy, irrespective of the photon energy. Three distinct forms of anion core previously proposed were confirmed that are monomeric, dimeric, and trimeric in nature. As the clusters grow in size from the monomer, the character of the anion core undergoes multiple switching until the first solvation shell is half-filled. Between the half-filled and completely-filled first solvation shell, the coexistence of the monomeric and dimeric anion cores was observed at certain cluster sizes, most notably at n = 8, 10, and 11. Only the monomeric form of anion core was observed once the first solvation shell is completely filled. [ABSTRACT FROM AUTHOR]

Mass spectrometric and anion photoelectron spectroscopic studies of homogeneous naphthalene cluster anions, (Nph)[sub n=2–7][sup -], were conducted to characterize the nature of their anionic cores. The smallest stable species in this series was found to be the naphthalene dimer anion. The vertical detachment energies of naphthalene clusters, n=2–7, were determined and found to increase smoothly with cluster size. By extrapolation, the vertical detachment energy of the isolated naphthalene molecule was found to be -0.18 eV, in agreement with its adiabatic electron affinity value from literature. The strong similarity between the spectral profiles of (Nph)[sub 2][sup -] and (Nph)[sub 1][sup -](H[sub 2]O)[sub 1] implied that (Nph)[sub 2][sup -] possesses a solvated monomeric anion core. All of the naphthalene cluster anions studied here were interpreted as having monomer anion cores. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Anions of mixed cluster between carbon dioxide (CO[sub 2]) and pyridine (C[sub 5]H[sub 5]N, denoted by Py), each possessing a negative adiabatic electron affinity, were studied. The minimum size cluster anion was the 1:1 complex of [(CO[sub 2])[sub 1](Py)[sub 1]][sup -], which displayed highest mass spectral intensity in the series. It was shown by photoelectron spectroscopy that [(CO[sub 2])[sub 1](Py)[sub 1]][sup -] is not a typically expected ion-molecule complex of the type (CO[sub 2])[sub 1][sup -](Py)[sub 1] or (CO[sub 2])[sub 1](Py)[sub 1][sup -]. Ab initio calculation in the UHF/6-311++G[sup **] level revealed that [(CO[sub 2])[sub 1](Py)[sub 1]][sup -] is indeed a totally new anion of the type (C[sub 5]H[sub 5]N-CO[sub 2])[sup -] with a planar C[sub 2v] structure, bound by an intermolecular bond of a strongly covalent character. The calculation predicted 1.24 eV for the vertical detachment energy of this anion, which is in reasonably good agreement with the measured value of 1.46 eV by photoelectron spectroscopy. A Mulliken analysis showed that the excess negative charge is fully delocalized throughout the entire molecular frame. Further calculation on intramolecular rotational barrier predicted a considerable barrier height of ∼0.68 eV, which could be due to an additional, weak π-bond character of the newly formed C-N σ-bond. Such extra π-bond network was suggested to provide a path for the charge delocalization and thus lead to the stability of the anion core. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The Association of Southeast Asian Nations (ASEAN) is planning to develop an ASEAN Highway Network, which links its ten Southeast Asian member countries by road. The plan is to improve economic growth, social progress and cultural development among its member countries.

The number of cancer patients has been rapidly increasing, and while there have been wide variations, cancer survival rates also improved globally. Despite the improved survival rates, supportive care needs of cancer patients have been unmet in various domains. The current study aimed to investigate unmet needs that had potential to be managed by peer supports according to cancer trajectories. We used the comprehensive needs assessment tool in cancer (CNAT) and a modified CNAT to evaluate the unmet needs and peer support needs of cancer patients at the tertiary hospital of South Korea. Of the 402 participants, 335 (83.3%) needed peer support. For patients who had been diagnosed with cancer for more than 5 years, the highest proportion of peer support needs to unmet supportive care was reported in information domain (92.9%). Patients with advanced cancer reported peer support needs in the social/religious/spiritual (84.4%) and practical domains (81.1%). Most of stomach cancer patients needed peer supports to receive information (96.6%). The need for peer supports in the information domain was reported highest according to longer survival period and also according to advanced cancer stages. The proportion of peer support needs in unmet supportive care varied by cancer type. Further interventional studies are needed to investigate satisfaction with peer support in specific domains. [ABSTRACT FROM AUTHOR]

Dispersion of oxide nanoparticles in W, leading to the dispersion strengthening of W alloys, has emerged as a viable strategy to overcome the brittleness of W. In particular, the introduction of stable Y 2 O 3 as a secondary phase refines the grain and enhances the densification of W, leading to an increase in the density of sintered alloy. Thus, analyzing the composite effects of Y 2 O 3 on the alloy, which has homogeneous dispersion of Y 2 O 3 nanoparticles, can allow enhanced mechanical properties of the W-Y 2 O 3 alloy. However, to date, most studies have focused on synthesis methodology for nanocomposites, which is advantageous to grain refinement and dispersion. It is worth paying attention to the interaction in the W-Y 2 O 3 system, such as the ternary oxide system (W-Y-O) with a low eutectic temperature and the possibility of liquid-phase sintering, which has been reported a few. In this study, the effect of Y 2 O 3 nanoparticles on the microstructure and micro-Vickers hardness of W was experimentally evaluated. W-Y 2 O 3 alloys with precisely controlled compositions from 1 wt% to 10 wt%Y 2 O 3 were successfully fabricated using an ultrasonic spray pyrolysis process and a subsequent spark plasma sintering. The proposed process yielded Y 2 O 3 nanoparticles with uniform dimensions and distributions even after sintering. Furthermore, the formation of Y 2 WO 6 and a liquid-phase sintered structure, as products of the interaction between W and Y 2 O 3 depending on the Y 2 O 3 fraction, were observed, and thermodynamical formation routes were suggested. Evidently, the W-2wt%Y 2 O 3 sintered alloy, with uniformly dispersed Y 2 O 3 nanoparticles (<50 nm), exhibited an improved hardness of 7.21 ± 0.15 GPa, as the W grains were refined to approximately 760 nm, and their density increased to 96.48%. • Ultrasonic spray pyrolysis process was employed to disperse 1–10 wt% Y 2 O 3 nanoparticles in the W matrix. • Homogeneous dispersion of Y 2 O 3 in W-Y 2 O 3 composites was achieved even at a high fraction of Y 2 O 3. • The Y 2 WO 6 phase and liquid-sintered structure were observed in W alloy with a composition above 5 wt% Y 2 O 3. • The W-2wt%Y 2 O 3 sintered alloy exhibited improved hardness due to densification and grain refinement by Y 2 O 3 nanoparticles. [ABSTRACT FROM AUTHOR]