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We consider in this paper relay assignment for cooperative systems with mutiple source-destination pairs. The objective here is to assign relays to the source-destination pairs in such a way that all pairs achieve the maximum diversity. In networks with mutiple source-destination pairs, it is normally difficult for destinations to acquire the channel state information (CSI) of the entire network without feedback. To this end, we design a practical limited feedback strategy in conjunction with two relay assignment schemes, i.e., fullset selection and subset selection, which are based on maximizing the minimum end-to-end (E2E) signal to noise ratio (SNR) among all pairs. In this strategy, each destination acquires its SNR, quantizes it, and feeds it back to the relays. The relays then construct the E2E SNR table and select the relay assignment permutation from all possible relay assignment permutations or only a subset of these permutations. We analyze the performance of these schemes over independent Rayleigh fading channels in terms of the worst E2E SNR. We derive closed-form expressions for the E2E bit error rate (BER) and investigate the asymptotic performance at high SNR. We show that relay assignment with quantized CSI can achieve the same first-order diversity as that of the full CSI case, but there is a second-order diversity loss. We also demonstrate that increasing the quantization levels yields performance that is close to that of having full knowledge of the CSI.

Designing of innovative technologies for the development of functional materials remain crucial for achieving sustainable technological advancements. In this regard, nanoparticles (NPs) possessing enormous potential properties can be obtained using various facile methods for several applications. Adopting NPs as primitive building blocks can initiate the formation of complex entities named supraparticle (SP) to create several advanced functional materials. Additionally, SPs enable entirely new material characteristics to the system, owing to their individual entities, intrinsic properties such as coupling, spatial arrangement, and co‐localization. Indeed, methods such as template‐induced evaporation‐based assembly of NPs direct the shape, size, and morphology of SPs from their respective colloidal dispersions on a solvent‐repellant solid surface. Therefore, it is important to comprehend the formation of SPs and their structure‐property relationship with respect to practical application. This review presents a brief overview of SPs assembly by outlining the templated‐assisted evaporation‐based methodologies for synthesizing SPs. Further, the effect of various factors on the interaction between colloidal entities, solvent, and substrate, leading to the genesis of SPs is elaborated. Conclusively, specific properties are described and applications of SPs for energy storage, generation, and environmental remediation are reported, which collectively brings many interdisciplinary research fields to the same podium. [ABSTRACT FROM AUTHOR]

Lithium‐mediated electrochemical nitrogen reduction reaction (Li‐NRR) completely eschews the competitive hydrogen evolution reaction (HER) occurred in aqueous system, whereas the continuous deposition of lithium readily blocks the active sites and further reduces the reaction kinetics. Herein, we propose an innovative in situ Li migration strategy to realize that Li substitutes Mn sites in λ‐MnO2 instead of evolving into the dead Li. Comprehensive characterizations corroborate that the intercalation of Li+ at high voltage breaks the structural integrity of MnO6 octahedron and further triggers unique Jahn–Teller distortions, which promotes the spin state regulation of Mn sites to generate the ameliorative eg orbital configuration and accelerates N≡N bond cleavage via eg‐σ and eg‐π* interaction. To this end, the resulted cationic disordered LiMnO4 delivers the recorded highest NH3 yield rate of 220 μg h−1 cm−2 and a Faradaic efficiency (FE) 83.80 % in organic electrolyte. [ABSTRACT FROM AUTHOR]

The effects of ultrasonic power (0, 150, 300, 450, and 600 W) on the extraction yield and the structure and rheological properties of pepsin-soluble collagen (PSC) from albacore skin were investigated. Compared with the conventional pepsin extraction method, ultrasonic treatment (UPSC) significantly increased the extraction yield of collagen from albacore skin, with a maximum increase of 8.56%. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed that peptides of low molecular weight were produced when the ultrasonic power exceeded 300 W. Meanwhile, secondary structure, tertiary structure, and X-ray diffraction analyses showed that the original triple helix structure of collagen was intact after the ultrasonic treatment. The collagen solutions extracted under different ultrasonic powers had significant effects on the dynamic frequency sweep, but a steady shear test suggested that the collagen extracted at 150 W had the best viscosity. These results indicate that an ultrasonic power between 150 and 300 W can improve not only the extraction yield of natural collagen, but also the rheological properties of the collagen solution without compromising the triple helix structure. [ABSTRACT FROM AUTHOR]

Solar‐driven water treatment suffers from low efficiency due to the solar energy loss during the energy conversion, especially in the scale‐up operation. One promising solution is using microlenses (MLs) to enhance the photodegradation of organic contaminants in water. However, most MLs fabrications apply to 2D planar surface only, which restricts their potential applications. In this study, a flexible and scalable technology is presented to fabricate MLs on curved surfaces. Precursor microdroplets form in a dilution process and are converted to MLs by photopolymerization. Optical simulations and experiments are combined to establish the correlation between optical properties of MLs and the performance of ML‐functionalized reactors in photodegradation. It is demonstrated that surface MLs on all‐shaped reactors significantly enhance the photodegradation efficiency of organic contaminants under simulated solar light or natural indoor light, with a maximum improvement of 83 folds. The surface coverage and size distribution of MLs can be adjusted by varying the solution concentration and the dilution rate when generating microdroplets. In addition, fabrication of MLs on a larger scale is achieved over an area up to 250 cm2 $\left(\text{cm}\right)^{2}$. MLs on 3‐dimensional curved surfaces fabricated by the technique enable significantly enhanced, highly customized, and sustainable solar‐driven water treatment. [ABSTRACT FROM AUTHOR]

In this work, a coherent and cost‐effective method is developed to achieve superhydrophobicity and excellent corrosion resistance on Q345B steel surfaces. The method involves sequential etching with hydrochloric acid and hydrofluoric acid, passivation with potassium permanganate, treatment with bis‐(γ‐triethoxysilylpropyl)‐tetrasulfide (KHSi69，BT), and modification with hydrophobic SiO2 nanoparticles. The effects of etching and passivation time, including SiO2 doping ratio on the wettability and corrosion resistance of the prepared surfaces are investigated. The results demonstrate that the surface exhibits a micro–nano multilayer and modified nano‐multiscale cluster structure which has a contact angle (CA) of 155.8 ± 1.7° and a sliding angle (SA) of 5 ± 0.5° by employing the following conditions: hydrochloric acid etching time of 10 min, hydrofluoric acid etching time of 25 min, passivation time of 300 min, and a 3 wt% SiO2 doping ratio. Moreover, the surface displays extremely weak droplet adhesion and excellent self‐cleaning properties. Furthermore, the corrosion inhibition of the prepared steel surface is evaluated using potentiodynamic polarization curves and electrochemical impedance spectroscopy. The results indicate that the corrosion inhibition efficiency of the superhydrophobic surface is enhanced by about 89.95% compared to the traditional two‐step processing involving etching and modification. These findings expand the potential applications of steel. [ABSTRACT FROM AUTHOR]