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The development of highly efficient electrocatalysts for complete oxidation of ethylene glycol (EG) in direct EG fuel cells is of decisive importance to hold higher energy efficiency. Despite some achievements, their progress, especially electrocatalytic selectivity to complete oxidated C1 products, is remarkably slower than expected. In this work, we developed a facile aqueous synthesis of Ir‐doped CuPd single‐crystalline mesoporous nanotetrahedrons (Ir‐CuPd SMTs) as high‐performance electrocatalyst for promoting oxidation cleavage of C−C bond in alkaline EG oxidation reaction (EGOR) electrocatalysis. The synthesis relied on precise reduction/co‐nucleation and epitaxial growth of Ir, Cu and Pd precursors with cetyltrimethylammonium chloride as the mesopore‐forming surfactant and extra Br− as the facet‐selective agent under ambient conditions. The products featured concave nanotetrahedron morphology enclosed by well‐defined (111) facets, single‐crystalline and mesoporous structure radiated from the center, and uniform elemental composition without any phase separation. Ir‐CuPd SMTs disclosed remarkably enhanced electrocatalytic activity and excellent stability as well as superior selectivity of C1 products for alkaline EGOR electrocatalysis. Detailed mechanism studies demonstrated that performance improvement came from structural and compositional synergies, which kinetically accelerated transports of electrons/reactants within active sites of penetrated mesopores and facilitated oxidation cleavage of high‐energy‐barrier C−C bond of EG for desired C1 products. More interestingly, Ir‐CuPd SMTs performed well in coupled electrocatalysis of anode EGOR and cathode nitrate reduction, highlighting its high potential as bifunctional electrocatalyst in various applications. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to assess the efficacy of continuous glucose monitoring (CGM) versus self‐monitoring of blood glucose (SMBG) in maintaining glycaemic control among people with type 2 diabetes mellitus (T2DM). Materials and Methods: The protocol was registered in PROSPERO (CRD42023387583). PubMed, Web of Science, EMBASE and OVID databases were searched from 1 January 2000 until 31 December 2022 for randomized controlled trials comparing CGM with SMBG in glycaemic control among the outpatients with T2DM. The primary endpoint was glycated haemoglobin, while the secondary endpoints included time in range, time below range and time above range. Both traditional and network meta‐analyses were conducted to explore the efficacy of CGM on glycaemic control in T2DM. Results: Eleven high‐quality studies, involving 1425 individuals with T2DM, were identified. Traditional meta‐analysis revealed that CGM exhibited a significantly decreased [mean difference (MD): −0.31, 95% confidence interval (CI) (−0.45, −0.18)], time above range [MD: −9.06%, 95% CI (−16.00, −2.11)], time below range [MD: −0.30%, 95% CI (−0.49, −0.12)] and a significantly increased time in range [MD: 8.49%, 95% CI (3.96, 13.02)] compared with SMBG. The network meta‐analysis showed that real‐time CGM can improve the glycaemic control of patients with T2DM to the most extent. Conclusions: CGM could provide T2DM with greater benefits in glycaemic management compared with SMBG, particularly in patients using real‐time CGM. These findings provide an updated perspective on previous research and offer guidance for CGM use in T2DM. [ABSTRACT FROM AUTHOR]

Although non‐fused ring electron acceptors (NFREAs) have received increasing attention due to their relatively low synthetic costs, the achievement of high efficiencies strongly depends on tedious pre‐ or/and post‐treatments to refine the active layers, which in turn greatly increase fabrication complexity and expense of organic solar cells (OSCs). Nowadays most of the available as‐cast devices based on NFREAs are below 12% efficiencies. Herein, phenylalkyl category side groups (CnPh) are employed to construct new NFREAs named BOR‐CnPh (n = 3, 4, and 6), which exhibit inherently decent molecular aggregation and thus exclude additional treatments from device fabrication. The modified alkyl spacers of CnPh side groups not only trigger different aggregation of the acceptors, but also regulate the interaction conformations of donor (D) and acceptor (A), and thus D/A interactions. Encouragingly, the pristine PBDB‐T:BOR‐C4Ph blend delivers intrinsic fibrous networks with dominating face‐on orientation, which yields an optimal efficiency up to 13.12%, and ranks as the highest value among as‐cast OSCs based on NFREAs. This research provides a practical strategy to control molecular aggregations, interactions, and pristine heterojunction morphologies for easily available and high‐performance organic photovoltaics. [ABSTRACT FROM AUTHOR]

The effect of the supersonic separator on the condensation characteristics and fluid separation efficiency is not clear, and the structure of the liquid separation device still has room for optimization. Therefore, based on the rear-swirl type supersonic separator, three kinds of drainage ports and three kinds of liquid collection tank structures were proposed. The supersonic flow and separation process was studied numerically under nine different combination structures. The influence of the drainage port's length and width and the inclination of the liquid collection tank on the liquefaction and separation process were analyzed. The separation trajectory of condensation droplets and the influence of particle size on the separation efficiency were clarified. The results show that the liquid separation device structure of the Em-Attached wall type can take condensation and separation efficiency into account, and its separation effect is the best. The optimal size of the key components was obtained: the length of the drainage port is 150 mm, the width of the drainage port is 3 mm, and the inclination of the liquid collection tank is 14 °. The particle size of the condensation droplets is in the range of 2 μm to 6 μm. [ABSTRACT FROM AUTHOR]

Based on the difference in the reaction rate of different groups of urea‐formaldehyde resins and isocyanate resins, this study designed two different urea‐formaldehyde resins: a normal urea‐formaldehyde resin (UF) and one with high mono‐hydroxymethylurea content (UF*) to react with polymeric methylene diphenyl diisocyanate (pMDI) resin. The difference in mono‐ and di‐hydroxymethyl urea content between UF and UF* resins was analyzed by nuclear magnetic resonance (NMR) spectroscopy, and results showed that the mono‐hydroxymethyl urea content of the UF* resin was much higher than that of the conventional UF resin. The fourier transform infrared spectrometer (FTIR) analysis of differences between UF* and UF resin showed that the UF* process did not change the main structure of the conventional urea formaldehyde resin. Differential scanning calorimeter (DSC) analysis showed that the curing temperature of the hybrid UF*‐pMDI resin was reduced 27.3°C compared to that of the UF‐pMDI resin. When these hybrid resins were used to bond plywood respectively, test results showed that the UF*‐pMDI resin improved the dry and wet bonding strength by 2.6% and 3.9%, respectively, compared with the UF‐pMDI resin under the condition of hot pressing time (3 min) and temperature (140°C), meeting the requirement of Chinese standard of GB/T 9846–2015 for Class III board. This study provides a new path for further improving the performance and design of hybrid resins based on isocyanate and urea‐formaldehyde resin. [ABSTRACT FROM AUTHOR]

Nonfullerene acceptors have boosted the power conversion efficiencies (PCE) of organic solar cells (OSCs). Rigid fused-ring molecular skeletons enable decent molecular planarity and stacking orientations, but suffer from tedious synthesis procedures for those with large π-backbones. Promisingly, the π-bridge strategy provides an alternative to readily manipulate the light utilization, but sometimes increases the conformation complexity. To rationally regulate the performance of π-bridged acceptors, herein, we report two new acceptors WA1 and WA2, functionalized with single or dual π-bridges flanking the phenylalkyl modified indacenodithiophene (IDT) backbone. The unilateral π-bridge endows WA1 with an asymmetric electron cloud distribution, affording a greater dipole moment and well-organized molecular orientation. In contrast, the bilateral π-bridges endow WA2 with two disparate molecular dipoles and disordered stacking orientations, generating inferior PCEs below 10%. Notably, the PM6:WA1 device shows a remarkable PCE of up to 15.45% with an impressive fill factor (FF) of up to 79.31%, both of which rank among the highest values of OSCs with π-bridged acceptors. More importantly, the PM6:Y6:WA1 ternary organic solar cell (TOSC) affords a high PCE of up to 18.15%, which is the best efficiency among Y6-based bulk-heterojunction TOSCs and the first example of an efficient ternary cell featuring a π-bridged guest acceptor. [ABSTRACT FROM AUTHOR]

Efficient organic solar cells (OSCs) equipped with thick‐film active layers and high flexibility are of great significance for industrial preparation and practical applications. Herein, a ternary strategy coupled with a functional additive is employed to obtain efficient thick‐film flexible OSCs. A novel polymer donor PBB1‐F with good planarity is synthesized as a third component to optimize photon capture and molecular stacking. Meanwhile, a high dielectric constant polyarene ether (PAE) functional additive with strong adhesion not only greatly improves exciton dissociation efficiency, but also acts as locking cage‐like for effective enhancement of the mechanical stability of active layer. As a result, the PM6:PBB1‐F:Y6‐BO‐4Cl and PM6:PBB1‐F:BTP‐eC9 based ternary OSCs with PAE exhibit an efficiency of 17.91% and 18.51% under rigid thin‐film state, and perform better under thick‐film state of rigid (16.40% and 16.84%) and flexible (14.78% and 14.95%). Under the protection of the polymers, tight entanglement and cage‐like PAE adhesion, the elongation at break of the active layer increases by more than fourfold (27.3%), and gives a super flexible thick‐film OSCs that maintains more than 90% performance after 1000 bending cycles with a diameter of 10 mm. Overall, this work provides a new feasible scheme to effectively solve thickness sensitivity and flexibility issues in the context organic photovoltaic applications. [ABSTRACT FROM AUTHOR]

Thanks to the development of acceptor–donor–acceptor (A–D–A) type electron acceptors, organic solar cells (OSCs) have achieved marvelous progress in recent years. However, a systematic investigation about the structure–efficiency relationship is still highly desired to better understand the working mechanisms inside a bulk heterojunction (BHJ). In this study, new acceptors with the synergistic effect of side chain and unilateral π‐bridge strategy are designed, accounting for lower energy loss, expanded absorption, modulated intermolecular interactions and BHJ morphology. As a consequence, the resultant A–D–π–A acceptor ID‐C6Ph‐ST‐4F based binary solar cell receives an impressive efficiency up to 15.36%, much greater than the A–D–A analog ID‐C6Ph‐4F (10.75%), and ranks the best among all small molecular acceptors with symmetric or asymmetric π‐bridges. The results highlight the promising manipulation of phenylalkyl side chain and unilateral π‐bridge on intermolecular interactions among acceptor molecules and interactions between donor and acceptor (D/A) molecules. Superior interactions among acceptor molecules are an essential precondition to ensure preferable molecular assembly for charge transport, and meanwhile, moderately enhanced D/A interactions are also crucial for proper phase‐separation networks with efficient exciton dissociation and charge generation. [ABSTRACT FROM AUTHOR]

Promoted by uninterrupted materials and device innovation, organic solar cells have achieved impressive development. However, the complicated intermolecular interactions inside active layers are less understood. Herein, the intermolecular interactions are studied from the dual perspectives of acceptor/acceptor (A/A) and donor/acceptor (D/A), and how these interactions synergistically control the final efficiencies. Three small molecular acceptors (SMAs) are designed with different end‐caps, which manipulate the crystallinity and electrostatic potential (ESP) distributions of acceptors, and accordingly, the A/A and D/A intermolecular interactions. The results show that SMA LA17 with low A/A interactions exhibits inferior performance around 12%, owing to its strong D/A interaction with donor PM6, which shapes too miscible morphology and increases charge recombination. Instead, LA16 with strong A/A interactions and moderate D/A interactions delivers improved bulk‐heterojunction (BHJ) networks, and therefore, enhances charge transport and diminishes geminate or trap‐assisted charge recombination. Consequently, PM6:LA16 records the competitive efficiency of up to 13.74% among the three systems. Therefore, this study deepens the synergistic or balancing effect of the D/A and A/A interactions on BHJ blends for efficient organic solar cells. [ABSTRACT FROM AUTHOR]

Settlement prediction in soft soil foundation engineering is a newer technique. Predicting soft soil settling has long been one of the most challenging techniques due to difficulties in soft soil engineering. To overcome these challenges, the wavelet neural network (WNN) is mostly used. So, after assessing its estimate performance, two elements, early parameter selection and system training techniques, are chosen to optimize the traditional WNN difficulties of readily convergence to the local infinitesimal point, low speed, and poor approximation performance. The number of hidden layer nodes is determined using a self-adaptive adjustment technique. The wavelet neural network (WNN) is coupled with the scaled conjugate gradient (SCG) to increase the feasibility and accuracy of the soft fundamental engineering settlement prediction model, and a better wavelet network for the soft ground engineering settlement prediction is suggested in this paper. Furthermore, we have proposed the technique of locating the early parameters based on autocorrelation. The settlement of three types of traditional soft foundation engineering, including metro tunnels, highways, and high-rise building foundations, has been predicted using our proposed model. The findings revealed that the model is superior to the backpropagation neural network and the standard WNN for solving problems of approximation performance. As a result, the model is acceptable for soft foundation engineering settlement prediction and has substantial project referential value. [ABSTRACT FROM AUTHOR]

Ternary organic solar cells (TOSCs) offer a facile and efficient approach to increase the power conversion efficiencies (PCEs). However, the critical roles that guest components play in complicated ternary systems remain poorly understood. Herein, two acceptors named LA1 and LA9 with differing crystallinity are investigated. The overly crystalline LA9 induces large self‐aggregates in PM6:LA9 binary system, resulting in a lower PCE (13.12%) compared to PM6:LA1 device (13.89%). Encouragingly, both acceptors are verified as efficient guest candidates into the host binary PM6:NCBDT‐4Cl (PCE = 13.48%) and afford markedly improved PCEs up to 15.39% and 15.75% in LA1 and LA9 ternary devices, respectively. Interestingly, the higher crystallinity LA9 reveals smaller interaction energies with both the host acceptor and donor PM6. Compared to LA1, the appropriate mutual interactions in the LA9 ternary system not only induces the orderly crystallinity of PM6 but also better compatibility with the host acceptor, generating further optimized molecular orientations and ternary morphology. Therefore, enhanced charge transport and minimized recombination loss are detected in LA9 ternary devices, affording the most competitive performance among Y6‐sbsent TOSCs. This work suggests that complicated intermolecular interactions should be seriously considered when fabricating state‐of‐the‐art multiple components OSCs. [ABSTRACT FROM AUTHOR]

Ternary polymer solar cells (PSCs) exhibit broader absorption bands, greater potential in micro-morphology regulation, energy level tuning, and other advantages compared with binary PSCs, and is a facile and efficient approach for further enhancing photovoltaic performances. Because of its much more complicated morphology-forming process, the ternary devices with two donors and one non-fullerene acceptor are difficult to regulate. In contrast, the ternary devices with one donor and two acceptors show greater potential in improving the morphology stability of the active layer film, which is one of the biggest obstacles that hinder the commercialization of PSCs. This review systematically summarizes the principles and functions of the third component of high-performance non-fullerenes ternary PSCs, and outlines the recent advancements of ternary PSCs with two donors and one non-fullerene acceptor, including two polymer donors and small molecular acceptor, all-polymer PSCs, and PSCs with small molecule donors. The relationship between the composition and property was carefully examined and outlined. In addition, the valuable guidelines in developing high-efficiency and high-stability non-fullerene ternary PSCs are demonstrated. [ABSTRACT FROM AUTHOR]

This study investigates the efficiencies of the exchange markets for four major currencies—the euro (EUR), the pound (GBP), the Canadian dollar (CAD) and the Japanese yen (JPY)—from 2005 to 2019 by using multifractal detrended fluctuation analysis (MF-DFA). This study also investigates the causes of these efficiencies. Significant multifractal properties are demonstrated by the four markets, and long-range correlation and fat-tail distribution properties are the main causes. We calculate and compare the multifractal degrees in three subsamples, which are classified based on their temporal relation to two economic events: the 2008 financial crisis and the announcement by the Federal Reserve of its withdrawal from the quantitative easing policy in 2014. Empirical results suggest that multifractal properties exist at different levels in the subsamples, thus showing that these events affect foreign exchange market efficiencies in terms of statistics and the fractal market. The JPY exchange market has the fewest multifractal properties, thus indicating that this exchange market has the highest market efficiency among these four exchange markets. The empirical results have implications for the nonlinear mechanism and efficiency in foreign exchange markets, which may help investors effectively manage market risks and benefit a stable global economy. [ABSTRACT FROM AUTHOR]

Huff‐n‐puff (HnF) is a crucial technology for effectively enhancing the oil recovery (EOR) of tight oil reservoirs. Soaking period is the primary platform for injection medium interacting with formation fluid and reservoir rock in HnF. Elucidating the micro‐percolation mechanism of the soaking period is immensely significant for guiding oilfield production practices. The present study established a physical simulation method combining HnF experiments with nuclear magnetic resonance to reveal the microscopic percolation mechanisms, including water, fracturing fluid, and surfactant. Furthermore, the impacts of soaking time, HnF cycles, wettability, and pore structure on oil recovery degree were quantified. The results demonstrate the crucial significance of wettability and pore structure in the soaking period. The dominant mechanism during water HnF in reservoirs characterized by well‐connected pore networks and minimal clay pores is micropore imbibition, while conversely, macropore displacement plays a predominant role. The oil recovery degree of fracturing fluid HnF primarily relies on mitigating solid‐fluid forces within macropores. The surfactant HnF in preferential water‐ and oil‐wet reservoirs is primarily governed by oil films stripped from macropore walls and micropore imbibition, respectively. Specifically, water and fracturing fluid HnF are suitable for shorter soaking time and fewer HnF cycles, whereas the surfactant HnF exhibits an inverse relationship. [ABSTRACT FROM AUTHOR]

This paper examines the daily return series of four main indices, including Shanghai Stock Exchange Composite Index (SSE), Shenzhen Stock Exchange Component Index (SZSE), Shanghai Shenzhen 300 Index (SHSE-SZSE300), and CSI Smallcap 500 index (CSI500) in Chinese stock market from 2000 to 2018 by multifractal detrended fluctuation analysis (MF-DFA). The series of the daily return of the indices exhibit significant multifractal properties on the whole time scale and SZSE has the highest multifractal properties among the four indices, indicating the lowest market efficiency. The multifractal properties of four indices are due to long-range correlation and fat-tail characteristics of the non-Gaussian probability density function, and these two factors have different effects on the multifractality of four indices. This paper aims to compare the multifractility degrees of the four indices in three sub-samples divided by the 2015 stock market crash and to discuss its effects on efficiency of the Shanghai and Shenzhen stock market in each sub-sample. Meanwhile, we study the effect of the 2015 stock market crash on market efficiency from the statistical and fractal perspectives, which has theoretical and practical significance in the application of Effective Market Hypothesis (EMH) in China's stock market, and it thereby affects the healthy and sustainability of the market. The results also provide important implications for further study on the dynamic mechanism and efficiency in stock market and they are relevant to portfolio managers and policy makers in a number of ways to maintain the sustainable development of China's capital market and economy. [ABSTRACT FROM AUTHOR]

• Malic acid/H 2 O 2 (HPMA) method efficiently degrades cured UF resins. • Process includes acidic hydrolysis & H 2 O 2 oxidation. • High molar ratio UF resins exhibit greater degradation resilience. • FTIR, XRD, NMR confirm structural changes during degradation. Urea-formaldehyde (UF) resin has a high annual output, but the used and waste UF resin poses a challenge for recycling due to the difficulty in effectively decomposition them. In this study, A novel one-step degradation method was proposed, i.e., using eco-friendly malic acid and hydrogen peroxide to degrade cured UF resin residues using carboxylic acid through the hydrothermal oxidation method (HPMA), which was proved to have high cured UF resin degradation efficiency. This method will offer a new path for effectively recycling the UF resin out of service. [ABSTRACT FROM AUTHOR]