Lauritsenacosta0015

Owing to the advantage of atomic utilization, the single-atom catalyst has attracted much attention and been employed in multifarious catalytic reactions. Its definite site configuration is favorable for exploring the actual active centers and corresponding reaction mechanism. At the atomic scale, the tunable site configuration, from central metal atoms, coordinated heteroatoms, peripheral dopants, and feasible polymetallic centers to the synergetic intrinsic carbon defects, can effectively augment the intrinsic activity for oxygen reduction reaction (ORR). From a practical viewpoint, the propagation strategies of single-atom sites, the loading-activity relation and the structural retention during practical tests are crucial for the industrial applications. Furthermore, the activity contribution of multiple additional active centers including the active carbon sites and the pony-size well-wrapped metal species should be acknowledged. From the perspective mentioned above, this paper thoroughly analyses the consensuses, controversies, challenges and possible solutions based on the current research progress, thereby providing inspiration and guidance for the active center engineering of single-atom catalysts.Bendiocarb, a type of carbamate pesticide, plays a crucial role in controlling a wide range of pests. Due to its harmful impact on humans and the environment, the need for inexpensive, portable, efficient and easy-to-use analytical devices has become essential. In this study, an environmentally friendly paper-based analytical device (PAD) with a chemiluminescence (CL) sensing platform was investigated and characterized for the facile, reliable and sensitive detection of the bendiocarb pesticide. It is based on the enhancing effect of SO32- on the CL reaction of sulfur, nitrogen-doped carbon quantum dots (S,N-CQDs)-KMnO4 in acidic media. According to the experiments, S,N-CQDs and SO32- both are oxidized by KMnO4 to generate (S,N-CQDs*) and (SO2*) in their excited states, emitting at 510 nm. This indicates that an energy transfer process is taking place from SO2* to S,N-CQDs, resulting in a remarkably intensified CL emission. Interestingly, another emission was also observed around 660 nm contributing to about 20 to 25% of the total CL emission. This emission is related to the Mn2+* species produced by reducing MnO4-. The established multi-emission CL system was tested for analytical applications. Under optimal experimental conditions, a good linear relationship was observed between the bendiocarb concentration and the CL intensity of the established CL system. The linear detection range was 0.1-10 μg mL-1, with a limit of detection (LOD) of 0.02 μg mL-1. Finally, the method was successfully applied for the measurements of bendiocarb in water and juice samples. The obtained recovery values (97.5-105.5) verified the suitable accuracy of the results.The adaptive response of bones to mechanical loading is essential for musculoskeletal development. Despite the importance of collagen in bone mineralization, little is known about how cyclic strain influences physicochemical responses of collagen, especially at the early stage of mineralization when the levels of strain are higher than those in mature bones. The findings in this study show that, without any cell-mediated activity, cyclic strain increases nucleation rates of calcium phosphate (CaP) nanocrystals in highly-organized collagen matrices. The cyclic strain enhances the transport of mineralization fluids with nucleation precursors into the matrix, thus forming more CaP nanocrystals and increasing the elastic modulus of the collagen matrix. The results also suggest that the multiscale spatial distribution of nanocrystals in the fibrous collagen network determines tissue-level mechanical properties more critically than the total mineral content. By linking nano- and micro-scale observations with tissue-level mechanical properties, we provide new insights into designing better biomaterials.The exploration of efficient electrocatalysts for the hydrogen evolution reaction (HER) is beneficial to obtain renewable clean energy. Herein, a new parkerite-type compound Pt3Bi2S2 was synthesized, constructed by [PtBi4S2] octahedra. The Bi 6p orbital electrons upshift the Pt 5d band to promote hydrogen adsorption. Moreover, the Bi-Pt orbital hybridization greatly improves the conductivity and accelerates the charge transfer during the electrocatalytic process. Hence, Pt3Bi2S2 exhibits a superior catalytic activity for the HER with a low overpotential of 61 mV (at j = 10 mA cm-2) and a Tafel slope of 51 mV dec-1. In addition, Pt3Bi2S2 has higher stability than commercial Pt/C. This work proposes a promising strategy for designing new excellent HER catalysts.An accurate and specific detection of viable Candida albicans (C. albicans) in vaginal discharge is crucial for the diagnosis of vulvovaginal candidiasis (VVC) and assessment of antifungal effects. In this study, improved propidium monoazide (PMAxx) and loop-mediated isothermal amplification (LAMP) were used for the first time to distinguish between viable and dead C. albicans. A portable microfluidic chip system was developed to detect multiple viable pathogens in parallel. The consumption of samples and reagents in per reaction cell were only 0.94 μL, less than 1/25 of the conventional 25 μL Eppendorf tubular test method, both significantly reducing testing cost and greatly simplifying the detection of multiple viable pathogens. The concentration of PMAxx was optimized against C. albicans at 4.0 log CFU mL-1 to 5.0 log CFU mL-1, and 1 μM PMAxx was proven to be suitable for the detection of C. albicans in clinical samples. When testing mixtures containing different ratios of viable to dead C. albicans, PMAxx-LAMP could circumvent the signal arising from dead cells and, therefore, reflected the abundance of viable cells precisely. Furthermore, the suitability of this technique to evaluate the effects of antifungal agents, including clotrimazole, miconazole, and tioconazole, was assessed. SC-43 manufacturer Finally, the viability of Escherichia coli (E. coli) and C. albicans were detected on the portable microfluidic chip system. PMAxx-LAMP based portable microfluidic chip system was determined to be a feasible technique for assessing the viability of multiple pathogens in gynecology and might provide insights into new VVC treatment strategies.