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Two piloted premixed CH $ _4 $ 4 /air jet flames with extreme turbulence are modelled using the Flamelet-Generated Manifold (FGM) method in the context of Large Eddy Simulation (LES). Free-propagating and reactant-to-product laminar flames are adopted to build unstrained and strained chemical databases, respectively. Detailed comparison of the LES-FGM results using the unstrained/strained databases is conducted which is validated against the direct numerical simulation results. The results show that whether including straining effects in the database will not influence the modelling of temperature and major species (e.g. CH $ _4 $ 4 , O $ _2 $ 2 and CO $ _2 $ 2 ), but using a strained database is essential for predictions of intermediate minor species (e.g. H $ _2 $ 2 , CH $ _2 $ 2 O, OH and CO). The main reason is that the major species and temperature are almost insensitive to the straining due to the supportive effects from the pilot flame, which also tentatively explains why the unstrained database can be employed to model these strong turbulent flames. In contrast, the intermediate minor species are more prone to the straining, so that using a strained database is crucial. The preferential diffusion effects on the species and temperature predictions are examined to be negligible. It is proposed that adding extra transport equations for these minor species also leads to satisfactory predictions if using an unstrained database, which helps to include the straining effects on the minor species. This study is expected to be significant in high-fidelity simulations of strong turbulent flames using flamelet-tabulated combustion models. [ABSTRACT FROM AUTHOR]

Overcoming exciton quenching and improving electroluminescence (EL) performances continue to pose persistent challenges in the development of efficient deep blue thermally activated delayed fluorescence (TADF) emitters. Herein, an asymmetric multi‐donors strategy is employed that provides the potential of establishing multiple radiative transition channels for fluorescence emission and reverse intersystem crossing (RISC), while allowing flexible modulation of packing modes in single‐crystal state and optimization of morphology in films by modifying the substitution site of the donor units. As a result, intermolecular π–π interactions are effectively alleviated and a very smooth surface with a reduced defect density is simultaneously achieved, which can significantly reduce the density of triplet excitons, accelerate the charge transfer rate, and enhance carrier injection efficiency. Consequently, a super‐high photoluminescence quantum yield (PLQY) of 99% and fast kRISC of 1.1 × 105 s−1 are concurrently achieved for the proof‐of‐concept emitter 3,4‐Cz‐SF‐SFAC. The corresponding deep‐blue organic light‐emitting diode (OLED) demonstrates an exceptional external quantum efficiency (EQE) of 31.1%, accompanied by an emission peak at 457 nm, one of the preeminent TADF materials within the deep blue region, ranking among the most efficient OLEDs with an EL spectra below 460 nm on record. [ABSTRACT FROM AUTHOR]

Multi‐resonance (MR) based organoboron emitters exhibiting high‐efficiency narrowband thermally activated delayed fluorescence (TADF) have become a critical material component for constructing high‐performance organic light‐emitting diodes (OLEDs) with high color purity and high color gamut. However, most of the MR‐TADF devices suffer from severe efficiency roll‐off at high current density due to the relatively large singlet–triplet splitting energy, long excited state lifetime, and slow reverse intersystem crossing rate (kRISC). Herein, by utilizing a sulfur atom‐fused donor unit, 7H‐benzo[4,5]thieno[2,3‐b]carbazole, an organic boron emitter (BTC‐BNCz) capable of high efficiency and low efficiency roll‐off narrowband TADF emission is developed. Benefitting from the heavy atom effect of the sulfur atom, kRISC up to 1.6 × 105 s−1 is achieved, which could greatly reduce the undesired quenching effect. Consequently, the OLED using BTC‐BNCz as dopant exhibits high external quantum efficiency (EQE) of 27.0% with full width at half maximum (FWHM) of 35 nm. Moreover, by utilizing a TADF material with a high horizontal dipole ratio as assistant host, outstanding device performance is achieved with a maximum EQE of 35.2% and FWHM of 37 nm, featuring slow efficiency roll‐off. [ABSTRACT FROM AUTHOR]

Solely through‐space charge transfer (TSCT)‐type thermally activated delayed fluorescent (TADF) emitters exhibit low radiative decay rates (krs$k_{\rm{r}}^{\rm{s}}$), while solely through‐bond charge transfer (TBCT) type TADF emitters generally suffer from low reverse intersystem crossing (RISC) rates (kRISC). Here, PhCzSpiroS‐TRZ with versatile spiro‐heterocyclic architecture and an extra donor of 9‐phenyl‐9H‐carbazole are developed as emitter and ideal host for TADF‐ and TADF‐sensitized fluorescence (TSF) organic light‐emitting diodes (OLEDs) in detail. Abandoning solely TSCT or TBCT process, PhCzSpiroS‐TRZ with multiple charge transfer characteristic exhibits photoluminescence quantum yield of 96.3% and krs$k_{\rm{r}}^{\rm{s}}$ of 2.2 × 107 s−1, which is considerably higher among all the reported TSCT‐TADF molecules. Noticeably, state‐of‐the‐art blue OLEDs using PhCzSpiroS‐TRZ as emitter and sensitizer show maximum external quantum efficiencies (EQEs) of 33.6% and 32.8%, ranking among TADF materials for achieving EQEs >30% in both TADF‐ and TSF‐OLEDs. [ABSTRACT FROM AUTHOR]

Pearson's chi-squared test is widely used to test the goodness of fit between categorical data and a given discrete distribution function. When the number of sets of the categorical data, say k, is a fixed integer, Pearson's chi-squared test statistic converges in distribution to a chi-squared distribution with k−1 degrees of freedom when the sample size n goes to infinity. In real applications, the number k often changes with n and may be even much larger than n. By using the martingale techniques, we prove that Pearson's chi-squared test statistic converges to the normal under quite general conditions. We also propose a new test statistic which is more powerful than chi-squared test statistic based on our simulation study. A real application to lottery data is provided to illustrate our methodology. [ABSTRACT FROM AUTHOR]

Metal halide perovskites have drawn substantial interest in optoelectronic devices in the past decade. Perovskite/electrode contacts are crucial for constructing high‐performance charge‐transporting‐layer‐free perovskite devices, such as solar cells, field‐effect transistors, artificial synapses, memories, etc. Many studies have evidenced that the perovskite layer can directly contact the electrodes, showing abundant physicochemical, electronic, and photoelectric properties in charge‐transporting‐layer‐free perovskite devices. Meanwhile, for perovskite/metal contacts, some critical interfacial physical and chemical processes are reported, including band bending, interface dipoles, metal halogenation, and perovskite decomposition induced by metal electrodes. Thus, a systematic summary of the role of metal halide perovskite/electrode contacts on device performance is essential. This review summarizes and discusses charge carrier dynamics, electronic band engineering, electrode corrosion, electrochemical metallization and dissolution, perovskite decomposition, and interface engineering in perovskite/electrode contacts‐based electronic devices for a comprehensive understanding of the contacts. The physicochemical, electronic, and morphological properties of various perovskite/electrode contacts, as well as relevant engineering techniques, are presented. Finally, the current challenges are analyzed, and appropriate recommendations are put forward. It can be expected that further research will lead to significant breakthroughs in their application and promote reforms and innovations in future solid‐state physics and materials science. [ABSTRACT FROM AUTHOR]

Despite the widespread application of data-centric techniques in Geotechnical Engineering, there is a rising need for building trust in the artificial intelligence (AI)-driven safety assessment of road embankments due to its so-called "black-box" nature. In addition, from the lens of limit equilibrium approaches, e.g., Bishop, Fellenius, Janbu and Morgenstern–Price, and finite element method, it is essential to carefully examine the interplay of both topological and physical/mechanical properties during the safety factor (FoS) predictions. First, aside from having conventional geotechnical inputs for soil in core and foundation and the height of embankments, this paper codifies geometric features innovatively. The number of slope types with different ratios including 1:1, 1.5:1 and 2:1 as well as the number of berms is introduced. Second, a pool of 19 machine learning (ML) techniques is effortlessly trained on the dataset using an automated ML (AutoML) pipeline to identify the most optimized ML algorithm. Finally, to achieve post-hoc interpretability for the internal mechanism of the input–output relationship unbiasedly, a game-theory-based explainable AI (XAI) method called Shapley additive explanations (SHAP) values is applied. SHAP-aided importance analysis provides human-interpretable insights and indicates height, California bearing ratio, slope type 2:1 and cohesion as the most influential parameters. Exclusively, analyzing hazardous embankments by classifying main and joint contributors exhibits a complex and highly variable influence on the FoS. This paper harnesses the power of XAI tools to enhance reliability and transparency for the rapid FoS prediction of slopes. It targets geotechnical researchers, practitioners, decision-makers, and the general public for the first time. • Shedding light on the AI-aided slope stability analysis with SHAP values. • Coupling AutoML and XAI for reliable and easy-to-use FoS prediction of embankments. • Defining novel geometric parameters to capture their impact on geotechnical ones. • Categorizing unstable embankments from the global and local XAI perspectives. • Analyzing hazardous embankments by classifying main and joint contributors. [ABSTRACT FROM AUTHOR]

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With the progress of sci-tech, the interdisciplinary and comprehensive development, and various advanced sci-tech gradually integrated into the field of sports, it has become possible to study how to reasonably prevent sports injuries, minimize the risk of sports injuries, and maintain the best physical condition of retired athletes. Due to the long-term high-load exercise of retired athletes during their sports career, athletes' physical functions have been damaged to varying degrees, resulting in more injuries. According to the characteristics that many factors need to be considered in the prediction of retired athletes' injuries, this paper puts forward an improved self-organizing neural network (SOM) method to predict retired athletes' injuries. In this paper, an early warning analysis model of retired athletes' susceptibility to injury based on SOM is proposed, which screens the state of retired athletes' physical function variables in each stage, considers athletes' physical function data whose standard deviation is higher than the limit specification of susceptibility to injury as susceptible injury data, quickly judges all vulnerable injury data, and completes the high-speed early warning analysis of retired athletes' susceptibility to injury. [ABSTRACT FROM AUTHOR]

Research on asphalt fatigue and self-healing performance can more accurately model the damage and self-healing evolution principles in practical applications. In order to analyze the rationality of evaluation indexes based on rheology to evaluate the self-healing properties of TPU modified asphalt, a dynamic shear rheometer (DSR) was used in this study to perform time, temperature, and frequency sweep tests of TPU modified asphalt for analyzing the fatigue self-healing properties of TPU modified asphalt over a broader range of temperatures and loading frequencies. This method can improve the accuracy of the fatigue failure determination criteria of TPU modified asphalt and clarify the material performance parameters of TPU asphalt modifiers. The results showed that the increase in hard segment content (C h) and isocyanate radical index (r) can effectively alleviate the decrease in shear deformation resistance of modified asphalt caused by the increase in N (load repetition). N f50 (the number of loads when the normalized modulus drops to 0.5) is more suitable to evaluate the fatigue life of TPU modified asphalt compared with N p20 (the number of loads when the DER - N curve is offset by 20% deviation from the linear undamaged line) and N 2 (the number of load times corresponding to the intersection point of the tangent line of the DER – N fitted curve and the undamaged line). The degree of self-healing will also increase with the increase in C h and r. Besides, the higher the healing temperature and the healing time, the longer the fatigue life. The effects of the self-healing evaluation index (HI) on the self-healing index of TPU modified asphalt were as follows: healing temperature > healing time > soft segment > C h > r > degree of damage > degree of aging > deg r ee of self-healing. • The effects of different segments of polyurethanes on the fatigue self-healing ability of modified asphalt were analyzed. • A viscoelastic master curve for comprehensive analysis of wide temperature and wide frequency bands was established. • The versatility and accuracy of N f50 as an evaluation index for the fatigue life of TPU modified asphalt were determined. • Through comparative experiments, the appropriate synthesis parameters and dosage of TPU asphalt modifier were determined. • The effects of factors on the self-healing index HI were analyzed and sorted by gray correlation coefficient. [ABSTRACT FROM AUTHOR]

Excessive reactive oxygen species (ROS) generated during cerebral ischemic reperfusion (CIRI) are crucial for subsequent tissue damage. However, despite the potential benefits of antioxidants reported in clinical applications, few have proven effective in treating CIRI, particularly in the elderly. Epicatechin (EC) is a catechol flavonoid monomer derived from natural tea plants. Multiple phenolic hydroxyl groups give it strong antioxidant properties, which can not only degrade ROS through chemical reactions between hydroxyl and ROS but also enhance the activity of antioxidant enzymes in cells, and it is easy to penetrate the blood–brain barrier. But its antagonistic effect on age‐related CIRI and potential medicinal value are still unknown. Nuclear factor erythroid 2‐related factor 2 (Nrf2) is the most important transcription factor regulating the expression of antioxidant proteins in the body. This study first compared the pathological differences of the Nrf2 system in CIRI between 2‐month‐old and 12‐month‐old Sprague–Dawley (SD) rats. Subsequently, EC was administered to 12‐month‐old rat models of middle cerebral artery occlusion and reperfusion (MCAO/R) and senescent SH‐SY5Y cell models subjected to oxygen glucose deprivation/reoxygenation (OGD/R). EC treatment improved cerebral morphology and function; increased p‐Nrf2, heme oxygenase‐1 (HO‐1), superoxide dismutase (SOD), and glutathione (GSH) expression; reduced infarct volume; and neuronal apoptosis in senescent rats. Moreover, EC enhanced cellular activity and the expression of p‐Nrf2, HO‐1, and quinone oxidoreductase‐1 (NQO‐1) while decreasing ROS and malondialdehyde (MDA) levels and mitigating apoptosis in senescent SH‐SY5Y cells. These effects were reversed upon si‐Nrf2. In sum, we confirm that EC exerts neuroprotective effects by upregulating Nrf2/ARE and reducing oxidative stress, suggesting that EC may be a promising drug for the treatment of senile cerebral apoplexy. This study also provides a scientific basis for the development and selection of new drugs for ischemic stroke in elderly patients. [ABSTRACT FROM AUTHOR]

• Numerical analysis of the performance of a new fishtail-type stirrer. • PIV experiments validate the correctness of the model. • Compared to the RT impellers, fishtail impeller reduce power consumption by 16.4 %. • Compared to the RT impeller, fishtail impellers are effective in reducing mixing times and increasing mixing efficiency. • The fishtail impeller increases the pumping flow by 13.5 % and the pumping efficiency by 27.66 % compared to the RT impeller. In this study, a new fishtail impeller was introduced to improve the mixing of fluids in the stirred tank. The validity of the numerical model was first demonstrated by PIV experiments. Secondly, the CFD technique was used to analyze and predict the flow field characteristics in the stirred tank. Also, the effect of blade inclination on the mixing effect is analyzed. Finally, a comparative Analysis with the whale tail impeller is carried out to demonstrate the superiority of this research work. The results show that The results of the study showed that the power number of the fishtail impeller was reduced by 16.4 % compared to the RT impeller. The pumping efficiency of the fishtail impeller was increased by 25.52 %. The results also show that increasing the blade inclination increases the turbulent kinetic energy in the stirred tank. Comparative analysis with the whale-tail impeller reveals that the power number of the fish-tail impeller is reduced by 17.2 % and the pumping efficiency is increased by 19.97 %. [Display omitted] [ABSTRACT FROM AUTHOR]

Electrode materials with two-dimensional (2-D) structures have attracted tremendous attention because they can exhibit many excellent electrochemical and chemical properties. Herein, we present a simple and general self-template-etched solution route to fabricate 2-D γ-manganese sulfide (γ-MnS) nanoplates using Mn3[Fe(CN)6]2 as a sacrificial template and Mn source. Detailed analysis and experimental results indicate that the ethylene glycol/H2O-assisted hydrothermal system and the unique metal frameworks are vitally important for the formation, structure, and morphology of plate-shaped γ-MnS during the sulfidation process. By controlling the growth and etching process, a possible growth mechanism was proposed to interpret the formation of 2D γ-MnS nanoplates. As a promising anode material for pseudocapacitors, the γ-MnS nanoplate sample not only delivers a good specific capacity of 378 F g−1 at 0.2 A g−1 and high rate capability in neutral solution, but it also displays an excellent stable performance, with only about 10% loss after continuous charge–discharge cycling for 4000 cycles at 1.0 A g−1. The method appears to be a new way for using the sulfuration transformation matrix to obtain other two-dimensional transition metal compounds. [ABSTRACT FROM AUTHOR]

Aims: To report experience of perioperative nursing of tracheal silicon stent implantation in infants. Methods: Retrospective analysis on the cases of tracheal silicon stent implantation in infants in our hospital. Results and Conclusions: Since middle of 2014, totally four tracheal silicon stent implantation were performed in our center. Of them, one case was recurrent tracheoesophageal fistula and the other three cases were traheomalacia. Parent’s psychological support, infants’ nutrition support and airway care were key responsibility for a nurse before implantation. During the procedure of stent implantation, it was responsible for a nurse to closely monitor the infants and to support operator. After the implantation, airway care and prevention of intra-airway bacterial colonization were important to avoid complications. [ABSTRACT FROM AUTHOR]

Two novel bipolar isomers, namely 3,5-bis(3-(9 H -carbazol-9-yl)phenyl)isonicotinonitrile ( m -DCzPyCN), and 3,5-bis(9-phenyl-9 H -carbazol-3-yl)isonicotinonitrile (3-DCzPyCN), are designed and synthesized by selecting cyanopyridine as n-type unit and N -phenylcarbazole as p-type unit. Two peripheral carbazoles are conjugated through their C-3 atom with the central cyanopyridine in 3-DCzPyCN but are indirectly linked through the N-9 atom via meta -phenylene bridges in m -DCzPyCN. The linking strategy had significant effect on the physical properties of the isomers. The single-carrier device study reveals that 3-DCzPyCN has much better positive and negative charge balancing ability than m -DCzPyCN. The 3-DCzPyCN hosted green phosphorescent organic light-emitting diode exhibits superior performance over m -DCzPyCN, with the maximum current efficiency of 84.1 cd A −1 and external quantum efficiencies of 24.2% and low efficiency roll-off. At an extremely high brightness of 10000 cd m −2 , the efficiency still remained at 78.4 cd A −1 , which corresponds to a roll-off of 6.7% from the maximum value. Even at an ultra-high brightness of 100000 cd m −2 , the efficiency is reduced by 47.0%. The superior performance of 3-DCzPyCN is ascribed to its remarkable charge balancing capability, which is the combined result of the cyanopyridine as n-type unit and the conjugated linking strategy between p- and n-type moieties. [ABSTRACT FROM AUTHOR]

Aims: To report experience of perioperative nursing of tracheal silicon stent implantation in infants.Methods: Retrospective analysis on the cases of tracheal silicon stent implantation in infants in our hospital.Results and Conclusions: Since middle of 2014, totally four tracheal silicon stent implantation were performed in our center. Of them, one case was recurrent tracheoesophageal fistula and the other three cases were traheomalacia. Parent's psychological support, infants' nutrition support and airway care were key responsibility for a nurse before implantation. During the procedure of stent implantation, it was responsible for a nurse to closely monitor the infants and to support operator. After the implantation, airway care and prevention of intra-airway bacterial colonization were important to avoid complications. [ABSTRACT FROM AUTHOR]

Consider the product of m independent n × n random matrices from the spherical ensemble for m ≥ 1 . The spectral radius is defined as the maximum absolute value of the n eigenvalues of the product matrix. When m = 1 , the limiting distribution for the spectral radii has been obtained by Jiang and Qi (2017). In this paper, we investigate the limiting distributions for the spectral radii in general. When m is a fixed integer, we show that the spectral radii converge weakly to distributions of functions of independent Gamma random variables. When m = m n tends to infinity as n goes to infinity, we show that the logarithmic spectral radii have a normal limit. [ABSTRACT FROM AUTHOR]

For bootstrap sample sums resulting from a sequence of random variables { X n , n ≥ 1 } , a very general central limit theorem is established. The random variables { X n , n ≥ 1 } do not need to be independent or identically distributed or to be of any particular dependence structure. Furthermore, no conditions, including moment conditions, are imposed in general on the marginal distributions of the { X n , n ≥ 1 } . As a special case of the main result, a result of Liu (1988) concerning independent but non-identically distributed { X n , n ≥ 1 } is extended to a larger class of parent sequences. A version of the main result is also presented wherein the bootstrap sample sums have random bootstrap sample sizes. [ABSTRACT FROM AUTHOR]

• Hosts with TADF, conventional fluorescence and RTP characters are developed. • Exciton utilization efficiency is improved by the host with TADF character. • An EQE of 36.1% was achieved for sky blue OLED with DspiroAc-TRZ as emitter. • An EQE of 34.0% was achieved for the sensitized device with v -DABNA dopant. Spiral donor units have attracted extensive research focuses in designing highly emissive thermally activated delayed fluorescence (TADF) emitters. Herein, to reveal the significance of spiral donor units for constructing highly efficient host materials, several spiral donor-based host materials are developed. With the incorporation of spiral donor, increased intermolecular distance is achieved to reduce the concentration quenching effect of dopant. Moreover, the high triplet energy level of spiral donor can provide an additional energy transfer channel to further improve the device performance. Noteworthy, by connecting spiral donors or conventional carbazole unit with different electron-withdrawing units phenoxathiine 10,10-dioxide (PX) or phenoxathiine (PA), these hosts are given different photophysical properties of TADF, room-temperature phosphorescence (RTP) and conventional fluorescence (CF). The strong electron-withdrawing ability of PX is beneficial to the TADF character of spiral donor-based molecules, while the weak electron-withdrawing ability of PA is beneficial to the RTP property. Consequently, the blue OLEDs with DspiroAc-TRZ as a dopant emitter based on the hosts with TADF characters exhibit higher performance than those with RTP and CF properties, and excellent external quantum efficiency (EQE) of 36.1 % and current efficiency of 84.6 cd/A are achieved in a simple device structure. Furthermore, peak EQEs of 34.0 % and 33.0 % are achieved, when DspiroS-PX and DspiroS-PA hosted DspiroAc-TRZ are used to sensitize blue multi-resonance TADF emitter v -DABNA. Our work may shed new light on designing highly efficient host materials for TADF emitters. [ABSTRACT FROM AUTHOR]

In order to investigate the convergence rate of the asymptotic normality for the estimator of the conditional mode function for the left-truncation model, we derive a Berry–Esseen type bound of the estimator when the lifetime observations with multivariate covariates form a stationary α-mixing sequence. The finite sample performance of the estimator of the conditional mode function is explored through simulations. [ABSTRACT FROM PUBLISHER]

Let 0 < p < 2 and 1 ≤ q < ∞. Let {Xn; n ≥ 1} be a sequence of independent copies of a real-valued random variable X and set Sn = X1 + · · ·+Xn, n ≥ 1. We say X satisfies the (p, q)-type strong law of large numbers (and write X ∈ SLLN(p, q)) if ... < ∞ almost surely. This paper is devoted to a characterization of X ∈ SLLN(p, q). By applying results obtained from the new versions of the classical Lévy, Ottaviani, and Hoffmann-Jørgensen (1974) inequalities proved by Li and Rosalsky (2013) and by using techniques developed by Hechner (2009) and Hechner and Heinkel (2010), we obtain sets of necessary and sufficient conditions for X ∈ SLLN(p, q) for the six cases: 1 ≤ q < p < 2, 1 < p = q < 2, 1 < p < 2 and q > p, q = p = 1, p = 1 < q, and 0 < p < 1 ≤ q. The necessary and sufficient conditions for X ∈ SLLN(p, 1) have been discovered by Li, Qi, and Rosalsky (2011). Versions of the above results in a Banach space setting are also given. [ABSTRACT FROM AUTHOR]

This paper deals with the conditional quantile estimation based on left-truncated and right-censored data. Assuming that the observations with multivariate covariates form a stationary α-mixing sequence, the authors derive the strong convergence with rate, strong representation as well as asymptotic normality of the conditional quantile estimator. Also, a Berry-Esseen-type bound for the estimator is established. In addition, the finite sample behavior of the estimator is investigated via simulations. [ABSTRACT FROM AUTHOR]

A cubic Mn 0.6 Fe 0.4 S solid solution material has been synthesized using a scalable in situ sulfuration treatment of Prussian-blue analogs (PBAs), and its phase formation process and Li-storage mechanism were investigated. Increased treatment temperature and time encourage a phase transformation from hexagonal Fe 7 S 8 to cubic FeS 2 during the sulfuration process, which results in the formation of a solid solution between cubic FeS 2 and cubic MnS. The resulting Mn 0.6 Fe 0.4 S solid solution electrode exhibits high initial coulombic efficiency, excellent rate performance, and superior cycling stability (520 mA h g−1 after 1000 cycles at 1.0 A g–1). Ex-situ X-ray diffractometry and electro-kinetics tests show that the doping-induced structural phase transition in Mn 0.6 Fe 0.4 S solid solution creates a favorable electronic structure and ensures rapid charge transfer kinetics during the lithiation/delithiation process, simultaneously achieving high energy conversion efficiency and a long lifespan. [Display omitted] • Cubic Mn 0.6 Fe 0.4 S solid solution as anode material is successfully synthesized. • The phase transition from α-MnS to metastable β-MnS could be induced in the charge process. • The improvement in electrochemical performance is attributed to the doping-induced structural phase transition in Mn0.6Fe0.4S. [ABSTRACT FROM AUTHOR]

Letbe a sequence of independent and identically distributedB-valued random variables, and set. Let,andq>0, and putWe strengthen the convergence rate for the Kolmogorov–Marcinkiewicz–Zygmund strong law of large numbers in Banach space, by showing that, if and only ifand [ABSTRACT FROM PUBLISHER]

Motivated by an investigation of finding necessary and sufficient conditions for the Kolmogorov strong law of large numbers for the general Gini's mean difference, new versions of the classical Lévy, Ottaviani, and Hoffmann-J\ooTrgensen inequalities are obtained for a sequence of Banach space valued random variables. No geometric conditions are imposed on the Banach space. An application to the general Gini's mean difference in a Banach space setting is presented. [ABSTRACT FROM PUBLISHER]

Sulfone‐embedded heterocyclics are of great interest in organic light‐emitting diodes (OLEDs), however, exploring highly efficient narrowband emitters based on sulfone‐embedded heterocyclics remains challenging. Herein, five emitters with different sulfur valence state and molecular rigidity, namely tP, tCPD, 2tCPD, tPD and tPT, are thoroughly analysed. With restricted twisting of flexible peripheral phenyl by strengthening molecular rigidity, molecular emission spectra can be enormously narrowed. Further, introducing the sulfone group with bending vibration in low‐frequency region that suppresses high‐frequency vibration, sharp narrow full‐widths at half‐maximum of 28 and 25 nm are achieved for 2tCPD and tPD, respectively. Maximum external quantum efficiencies of 22.0 % and 27.1 % are successfully realized for 2tCPD‐ and tPD‐based OLED devices. These results offer a novel design strategy for constructing narrowband emitters by introducing sulfone group into a rigid molecular framework. [ABSTRACT FROM AUTHOR]

Sulfone‐embedded heterocyclics are of great interest in organic light‐emitting diodes (OLEDs), however, exploring highly efficient narrowband emitters based on sulfone‐embedded heterocyclics remains challenging. Herein, five emitters with different sulfur valence state and molecular rigidity, namely tP, tCPD, 2tCPD, tPD and tPT, are thoroughly analysed. With restricted twisting of flexible peripheral phenyl by strengthening molecular rigidity, molecular emission spectra can be enormously narrowed. Further, introducing the sulfone group with bending vibration in low‐frequency region that suppresses high‐frequency vibration, sharp narrow full‐widths at half‐maximum of 28 and 25 nm are achieved for 2tCPD and tPD, respectively. Maximum external quantum efficiencies of 22.0 % and 27.1 % are successfully realized for 2tCPD‐ and tPD‐based OLED devices. These results offer a novel design strategy for constructing narrowband emitters by introducing sulfone group into a rigid molecular framework. [ABSTRACT FROM AUTHOR]

Abstract: Let be a double array of nondegenerate i.i.d. random variables and let be a sequence of positive integers such that is bounded away from 0 and . This paper is devoted to the solution to an open problem posed in Li et al. (2010) on the asymptotic distribution of the largest entry of the sample correlation matrix where denotes the Pearson correlation coefficient between and . We show under the assumption that the following three statements are equivalent: where and , . To establish this result, we present six interesting new lemmas which may be of independent interest. [Copyright &y& Elsevier]

Let {Yn, n ≥ 1} be a sequence of i.i.d. random variables and let l and L denote the essential infimum of Y1 and the essential supremum of Y1, respectively. The set  of almost sure limit points of [image omitted] where b > 1 is investigated. The new findings are for the case where Y1 is unbounded and are as follows: (i) If  ∩  ≠ ∅, then  = [l, L]; (ii) If l ∈ , then either  = {∞} or  = [l, ∞]; (iii) If l = - ∞ and L = ∞, then either  = {∞},  = {- ∞},  = [- ∞, ∞], or  = {- ∞, ∞}. Illustrative examples are referenced or provided showing that each of the various alternatives can hold. The current work is a continuation of the investigations of Li et al. [3, 4] wherein the set  is identified, respectively, for bounded Y1 as the spectrum of the distribution function of [image omitted] and for unbounded Y1 with (log (max {|Y1|, e})) < ∞ as [l, L]. [ABSTRACT FROM AUTHOR]

Abstract: This note is devoted to a generalization of the Strassen converse. Let , be a sequence of measurable functions such that, for every , and for all , where is a constant which is independent of n. Let be a sequence of i.i.d. random variables. Assume that there exist and a function with , depending only on the sequence such that a.s. whenever and . We prove the converse result, namely that a.s. implies (and if, in addition, for all ). Some applications are provided to illustrate this result. [ABSTRACT FROM AUTHOR]

Abstract: Motivated by the study of risk measures in mathematical finance, we study the relationship between the relevance and no arbitrage properties of a specific class of mappings acting on ordered vector spaces. Our findings justify the relationships between these two properties, a theoretical primer in the literature. [Copyright &y& Elsevier]

Abstract: In this paper we derive rates of uniform strong convergence for the kernel estimator of the regression function in a left-truncation model. It is assumed that the lifetime observations with multivariate covariates form a stationary -mixing sequence. The estimation of the covariate’s density is considered as well. Under the assumption that the lifetime observations are bounded, we show that, by an appropriate choice of the bandwidth, both estimators of the covariate’s density and regression function attain the optimal strong convergence rate known from independent complete samples. [Copyright &y& Elsevier]

For a sequence of i.i.d. mean 0 random variables {X, Xn; n ≥ 1} with partial sums [image omitted], necessary and/or sufficient conditions are provided for {X, Xn; n ≥ 1} to enjoy iterated logarithm type behavior of the form [image omitted] almost surely where h(·) is a positive, nondecreasing function that is slowly varying at infinity. New results are {obtained for the cases X2 < ∞ and X2 = ∞. The proofs rely heavily on recent work of Einmahl and Li (Annals of Probability (2005) 33:1601-1624) and new versions of those results are obtained under conditions couched in terms of an “integral test” involving whether [image omitted] is finite or infinite where Lx = loge(e ∨ x) for x ≥ 0. Corollaries are presented for particular choices of h(·). [ABSTRACT FROM AUTHOR]

Asymptotic error expansions in the sense of L ∞-norm for the Raviart-Thomas mixed finite element approximation by the lowest-order rectangular element associated with a class of parabolic integro-differential equations on a rectangular domain are derived, such that the Richardson extrapolation of two different schemes and an interpolation defect correction can be applied to increase the accuracy of the approximations for both the vector field and the scalar field by the aid of an interpolation postprocessing technique, and the key point in deriving them is the establishment of the error estimates for the mixed regularized Green’s functions with memory terms presented in R. Ewing at al., Int. J. Numer. Anal. Model 2 (2005), 301–328. As a result of all these higher order numerical approximations, they can be used to generate a posteriori error estimators for this mixed finite element approximation. [ABSTRACT FROM AUTHOR]

Abstract: Let be a sequence of i.i.d. real-valued random variables and set , . Let be a positive nondecreasing function such that . Define for . In this note we prove that if and only if and , where , . When , this result yields what is called the Davis–Gut law. Specializing our result to , , we obtain an analog of the Davis–Gut law. [Copyright &y& Elsevier]

Abstract: Let be a sequence of real-valued i.i.d. random variables with and , and set , . This paper studies the precise asymptotics in the law of the iterated logarithm. For example, using a result on convergence rates for probabilities of moderate deviations for obtained by Li et al. [Internat. J. Math. Math. Sci. 15 (1992) 481–497], we prove that, for every , whenever , where , , , , and , . This result generalizes and improves Theorem 2.8 of Li et al. [Internat. J. Math. Math. Sci. 15 (1992) 481–497] and Theorem 1 of Gut and Spătaru [Ann. Probab. 28 (2000) 1870–1883]. [Copyright &y& Elsevier]

Herein, we propose a regional functionalization molecular design strategy that enables independent control of distinct pivotal parameters through different molecule segments. Three novel multiple resonances thermally activated delayed fluorescence (MR‐TADF) emitters A‐BN, DA‐BN, and A‐DBN, have been successfully synthesized by integrating highly rigid and three‐dimensional adamantane‐containing spirofluorene units into the MR framework. These molecules form two distinctive functional parts: part 1 comprises a boron‐nitrogen (BN)‐MR framework with adjacent benzene and fluorene units forming a central luminescent core characterized by an exceptionally rigid planar geometry, allowing for narrow FWHM values; part 2 includes peripheral mesitylene, benzene, and adamantyl groups, creating a unique three‐dimensional "umbrella‐like" conformation to mitigate intermolecular interactions and suppress exciton annihilation. The resulting A‐BN, DA‐BN, and A‐DBN exhibit remarkably narrow FWHM values ranging from 18 to 14 nm and near‐unity photoluminescence quantum yields. Particularly, OLEDs based on DA‐BN and A‐DBN demonstrate outstanding efficiencies of 35.0 % and 34.3 %, with FWHM values as low as 22 nm and 25 nm, respectively, effectively accomplishing the integration of high color purity and high device performance. [ABSTRACT FROM AUTHOR]

Herein, we propose a regional functionalization molecular design strategy that enables independent control of distinct pivotal parameters through different molecule segments. Three novel multiple resonances thermally activated delayed fluorescence (MR‐TADF) emitters A‐BN, DA‐BN, and A‐DBN, have been successfully synthesized by integrating highly rigid and three‐dimensional adamantane‐containing spirofluorene units into the MR framework. These molecules form two distinctive functional parts: part 1 comprises a boron‐nitrogen (BN)‐MR framework with adjacent benzene and fluorene units forming a central luminescent core characterized by an exceptionally rigid planar geometry, allowing for narrow FWHM values; part 2 includes peripheral mesitylene, benzene, and adamantyl groups, creating a unique three‐dimensional "umbrella‐like" conformation to mitigate intermolecular interactions and suppress exciton annihilation. The resulting A‐BN, DA‐BN, and A‐DBN exhibit remarkably narrow FWHM values ranging from 18 to 14 nm and near‐unity photoluminescence quantum yields. Particularly, OLEDs based on DA‐BN and A‐DBN demonstrate outstanding efficiencies of 35.0 % and 34.3 %, with FWHM values as low as 22 nm and 25 nm, respectively, effectively accomplishing the integration of high color purity and high device performance. [ABSTRACT FROM AUTHOR]

Recently, an ever‐growing interest has been paid on organic single‐molecule white light‐emitting materials for effective white organic light‐emitting diodes (WOLEDs). However, subject to Kasha's rule, photons can only be emitted from the lowest excited state and thus panchromatic or dual emissions are extremely forbidden, which results in a certain challenge in achieving white emission. Herein, a strategy of synergetic carbonyl and heptagonal structure is proposed for organic single‐molecule white light emission and demonstrated by TAO/TABO/TA2O organic luminescent materials that are modified on aryl ketones/amine fragments. Among them, due to the robust intermolecular interactions triggered by synergetic carbonyl and heptagonal structure, TA2O exhibits vibrant monomer and dimer photoluminescence with dual thermally activated delayed fluorescence (TADF) characteristics. As a result, the first single‐molecule dual‐TADF WOLED based on the synergetic system is successfully fabricated with an external quantum efficiency of 7.2%. This study not only expands the scope of carbonyl and heptagonal structure for novel optoelectronic properties and applications but also opens new avenues for the development of efficient single‐molecule WOLEDs with dual TADF mechanisms. [ABSTRACT FROM AUTHOR]

Sulfone group plays a pivotal role in narrowing emission spectra, while, precise modification with sulfone group for carbonyl‐based narrowband emitters that maintain high color purity remains challenging. Herein, a comprehensive exploration of the function of the sulfone group is performed with various sulfur valences and positions fused into traditional carbonyl‐based narrowband emission unit QAO, namely SpiroS‐QAO, SpiroSO2‐QAO, SpiroO‐QAO, and SpiroOSO2‐QAO. A rigid molecular skeleton with a spiro structure as an intramolecular lock enables the four emitters to exhibit narrowband emissions. After full oxidization of sulfur, the emission band of SpiroSO2‐QAO is further narrowed, with full width at half maximum of 32 nm, compared to that of 43 nm for sulfane‐decorated SpiroS‐QAO, which is attributed to the suppressed C─S bond‐length variation by the introduction of sulfone group. Nearly identical spectra of SpiroO‐QAO and SpiroOSO2‐QAO suggest that the sulfone group should be directly linked to the emission core to maximize its function. Maximum external quantum efficiencies of 30.8%, 30.3%, and 29.2% are achieved for SpiroO‐QAO, SpiroOSO2‐QAO, and SpiroS‐QAO‐based sensitized organic light‐emitting diodes with highly efficient thermally activated delayed fluorescence assistant host. These results offer a comprehensive understanding of the sulfone group embedded into the narrowband emission core with respect to the narrowing emission band. [ABSTRACT FROM AUTHOR]

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