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Coalescence-induced droplet jumping on superhydrophobic surfaces has been observed at microscale and even nanoscale. The enhancement in jumping velocity of coalescing droplets is crucial for condensation heat transfer enhancement, antiicing, self-cleaning, and so forth. However, the research on how to acquire a higher jumping velocity is really very limited. In this paper, we use molecular dynamics simulations to study the coalescence-induced jumping of two equally sized nanodroplets on chemically heterogeneous surfaces composed of alternating stripes with different hydrophobicity. We show that the jumping velocity is closely related to the stripe width and wettability contrast, and it can even exceed that on an ideal superhydrophobic surface with 180 [degrees] contact angle when the striped surfaces are properly designed. We also demonstrate that there is always an optimal stripe width yielding the maximum jumping velocity, whereas its value is independent of the wettability contrast. We reveal that the dominant factor to determine the jumping velocity is the apparent contact angle of equilibrated droplets over heterogeneous surfaces for small stripe widths; it changes to the time of liquid bridges impacting surfaces for moderate stripe widths and to the contact area between equilibrated droplets and relatively hydrophobic stripes for large stripe widths. We believe the present simulations can provide useful guidance to design self-jumping superhydrophobic surfaces. Key words: mixed-wettability, superhydrophobic surfaces, coalescence, jumping velocity, molecular dynamics simulations. Les sauts de gouttelettes induits par coalescence sur une surface super-hydrophobe s'observent aux echelles micro et nano. L'accroissement de la vitesse de saut des gouttelettes se fusionnant est cruciale pour l'augmentation du transfert de chaleur par condensation, pour l'antigivrage, l'auto-nettoyage, etc. Cependant, il n'y a que tres peu de recherche sur le moyen d'augmenter la vitesse de saut. Nous utilisons ici des simulations de dynamique moleculaire pour etudier le sautillement, induit par leur fusion, de deux nano-gouttelettes de meme grosseur sur des surfaces chimiquement heterogenes composees de bandes alternees de differente hydrophobicite. Nous montrons que la vitesse de saut est etroitement reliee a la largeur de ces bandes et du contraste de mouillabilite et qu'elle peut meme exceder celle sur une surface superhydrophobe continue ideale avec un angle de surface de 180 [degrees], a condition que les surfaces striees soient concues de facon appropriees. Nous annoncons aussi qu'il y a une largeur de bande optimale produisant une vitesse de saut maximale, et que sa valeur est independante du contraste de mouillabilite. Nous revelons que, sur les surfaces heterogenes avec des bandes de petites largeurs, le facteur dominant pour determiner la vitesse de saut est l'angle de contact apparent des gouttelettes en equilibre, mais pour des bandes de largeur moyenne, ce facteur dominant devient le temps du pont liquide impactant la surface, alors que pour des bandes de grande largeur, il devient la surface de contact entre les gouttelettes equilibrees et les bandes relativement hydrophobes. Nous croyons que les resultats de ces simulations fourniront des guides utiles dans la conception des surfaces super-hydrophobes auto-sautillantes. [Traduit par la Redaction] Mots-cles : mouillabilite mixte, super-hydrophobe, coalescence/fusion, vitesse de saut, simulations de dynamique moleculaire., 1. Introduction Coalescence-induced droplet jumping on superhydrophobic surfaces was first discovered by Boreyko and Chen in 2009 [1]. Over the past decade, this phenomenon has received more and more attention [...]

Single‐molecule magnets (SMMs) show wide potential applications in the field of ultrahigh‐density storage materials, quantum computing, spintronics, and so on. Lanthanide (Ln) SMMs, as an important category of SMMs, open up a promising prospect due to their large magnetic moments and huge magnetic anisotropy. However, the construction of high performance for Ln SMMs remains an enormous challenge. Although remarkable advances are focused on the topic of Ln SMMs, the research on Ln SMMs with different nuclear numbers is still deficient. Therefore, this review summarizes the design strategies for the construction of Ln SMMs, as well as the metal skeleton types. Furthermore, we collect reported Ln SMMs with mononuclearity, dinuclearity, and multinuclearity (three or more Ln spin centers) and the SMM properties including energy barrier (Ueff) and pre‐exponential factor (τ0) are described. Finally, Ln SMMs with low‐nuclearity SMMs, especially for single‐ion magnets (SIMs), are highlighted to understand the correlations between structures and magnetic behavior of the detail SMM properties are described. We expect the review can shed light on the future developments of high‐performance Ln SMMs. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy and the safety of low dose salmeterol/fluticasone (SM/FP) combination therapy as compared to morate dose of budesonide (BUD) in the management of adult asthma., Methods: A multicentre, randomised, open-label, parallel-group, 6-week treatment study was conducted. 398 patients (18 - 70 years) were given SM/FP (50/100 microg) twice daily via Accuhaler or BUD 400 microg twice daily via Turbuhaler., Results: The morning and the evening peak expiratory flow (PEF) measurements both increased significantly (P < 0.01) in the SM/FP group, and the increase was greater than that in the BUD group. The significant benefit of SM/FP was evident from the first week. SM/FP led to a more significant reduction in the use of rescue medication and in the day- and night-time asthma symptom scores, as compared to budesonide. Both treatments were well tolerated, and the adverse reactions showed no significant difference between the two groups., Conclusions: Combination use of low doses of SM/FP is a better choice for the control of asthma. The addition of a low-dose long-acting beta(2) agonist is superior to the simple increase of the dosage of inhaled corticosteroids.