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Photomultiplication-type organic photodetectors (PM-OPDs) have been stimulating more and more researchers' interest owing to their extremely high external quantum efficiency (EQE). To prepare high-performance PM-OPDs with a broadband spectral response range from visible to near-infrared and investigate the role of energy levels of the donor and acceptor on its responsiveness, the non-fullerene acceptor Y6 was added into the P3HT:PC71BM system in this work. The photomultiplication phenomenon with the highest EQE has been achieved under both forward and reverse bias when the ratio of Y6 in two acceptors approaches 80 wt. %. The introduction of Y6 not only promotes the formation of moderate hole traps in the active layer but also results in an appropriate amount of low injection barriers to allow more electron injection from the external circuit. Therefore, the spectral response of the device with 80 wt. % Y6 has been broadened from 750 to 950 nm, and the champion EQE of 15 691% at 10 V and 7639% at −20 V at 850 nm was achieved. This work reveals the importance of hole-trapping ability determined by the energy level difference between the donor and the acceptor for the selection of the multiplication system and provides a scheme for the design of high-performance broadband PM-OPDs. [ABSTRACT FROM AUTHOR]

Wax deposition of diesel oil and contamination of gasoline by diesel wax deposit is a severe problem in sequential transportation of product oil in pipes. However, it has long been neglected by the pipeline transportation industry. In response, this work aims to present a unique perspective on wax deposition of diesel oil and consequent contamination of gasoline. A cold finger apparatus was designed and constructed. Model oil composed of diesel and refined wax was prepared for wax deposition. Shear dispersion was excluded for wax deposition of diesel oil. Moreover, dissolution experiments of diesel wax deposit in gasoline were conducted. It was found that the dissolution rate increases with oil temperature and decreases with cold finger temperature and shear stress. Analysis on gasoline quality after diesel wax deposit dissolution indicated that contamination of gasoline caused by diesel wax deposit severely deteriorates its distillation range, but the octane number remains acceptable. This work features an interesting investigation on the wax-deposition mechanism of diesel oil, dissolution characteristics of diesel wax deposit, as well as quality deterioration of subsequent gasoline. It would be helpful in scheduling a product oil-transportation program. [ABSTRACT FROM AUTHOR]

Railway accidents caused by gales are indeed influenced by multiple factors, making them a complex process. However, current research and monitoring systems often focus solely on wind speed, overlooking the combined effects of other factors. This paper proposes a data-driven assessment strategy specifically designed for high-speed railways. The disaster-inducing factor, disaster-pregnant environment, disaster-bearing body, and disaster prevention/mitigation capabilities are all taken into consideration. Moreover, it explores the interrelationships between these factors. To validate the proposed mechanism, the spatial-temporal distribution of gale-induced risks along China's high-speed railways is studied in this paper. By analyzing and interpreting the data, the researchers are able to identify areas and time periods that are particularly prone to gale-induced accidents. These findings are crucial for the development of effective strategies for disaster prevention and mitigation in the context of high-speed railways. [ABSTRACT FROM AUTHOR]

Herein, a new template carbonization method is used to prepare calcite‐type nano‐calcium carbonate (CaCO3) with a core–shell structure using calcium hydroxide as a solute and Pluronic F‐127 as a templating and pore‐forming agent. Dopamine hydrochloride is added to control the size of calcium hydroxide particles. The morphology, particle size, and crystal type of CaCO3 are characterized via transmission electron microscopy, X‐ray diffraction, nanoparticle size, and zeta potentiometer. The creation of core–shell calcium carbonate nanoparticles is examined in relation to reaction circumstances (i.e., additive sequence, additive amount, and additive mixing time), carbonization temperature, liquid flow rate, and templates with varying chain lengths. Furthermore, a discussion is held regarding the formation mechanism of spherical core–shell calcium carbonate that is created using the innovative template carbonization method. The results show that the order, amount, liquid flow rate, and template type of additives have a significant effect on the crystal shape of calcium carbonate nanoparticles. The mixing time of additives has a significant effect on the particle size of calcium carbonate nanoparticles. Interestingly, the thickness of the shell depends on the carbonization temperature, and too slow or too fast flow rate will lead to the formation of cyclic calcium carbonate nanoparticles. [ABSTRACT FROM AUTHOR]

Herein, a novel bimetallic nickel molybdenum nitride (Ni3Mo3N) catalyst is reported for the first time for the hydrogenation of dimethyl oxalate (DMO) to ethanol (EtOH). Remarkably, the Ni3Mo3N-600 catalyst realizes a remarkable 97.5% EtOH yield at a low pressure of 0.5 MPa and a low H2/DMO molar ratio of 10. Moreover, it exhibits exceptional catalytic stability for at least 300 h, marking the first instance of achieving such high EtOH yield under mild reaction conditions. The present study investigates the impact of different reduction temperatures on the catalyst, and various characterization analyses reveal the formation of Ni3Mo3N. The electron-rich structure of the Ni3Mo3N-600 catalyst facilitates the activation of C＝O and enhances the adsorption and dissociation of H2. Specifically, the low-valence Mo promotes the activation of carbonyl oxygen, while Ni0 facilitates the adsorption and dissociation of H2, considerably enhancing the deep hydrogenation ability of the Ni3Mo3N-600 catalyst. Furthermore, the well-defined crystallinity of the Ni3Mo3N-600 catalyst coupled with Lewis acid sites that promote C＝O adsorption and activation, Brønsted acid sites that facilitate C–O adsorption and activation, and hydrogenation sites collectively contribute to the efficient conversion of DMO to EtOH. This study presents new insights into designing high-performance catalysts for the hydrogenation of DMO toward EtOH. [ABSTRACT FROM AUTHOR]

Contamination of gasoline by wax deposit of diesel is a severe problem in sequential transportation of product oil pipelines in cold areas. However, most works on wax deposition are focused on crude oil. In response, this paper aims to investigate wax deposition from a unique perspective of diesel oil in sequential transportation. To this end, a cold finger apparatus was designed and constructed. It is found that the wax deposition rate of diesel oil increases with oil temperature and wax content, and decreases with cold finger temperature. A non‐monotonic variation trend is observed against shear stress. To predict diesel wax deposition rate, a back propagation (BP) neural network optimized by bald eagle search (BES) algorithm is proposed. Grey relational analysis (GRA) is employed to get the highly relevant factors as input parameters of the developed model. Prediction accuracy and generalization ability of the BES‐BP model is experimentally verified. This work will be helpful to schedule the transportation program of product oil to avoid contamination of gasoline by diesel wax deposit. [ABSTRACT FROM AUTHOR]

Summary: Reinforced concrete (RC) shear walls play an important role as the seismic resisting system in tall buildings. Yet, assessing the seismic damage of real‐world shear walls remains a challenging task. In this study, a damage index that relies on the vibration data measured by the sensors embedded in the structure is proposed to evaluate the damage condition of shear walls. The damage index is formed by the linear combination of two normalized terms, which, respectively, characterize the peak and the cumulative damages of the shear walls with little knowledge of real‐life structural hysteresis. The damage tracking and evaluation based on the substructure level and the story level are discussed. The damage indices evaluated using the hysteretic loops made by the shear and bending information of the shear wall are further compared. The feasibility of the proposed damage index is examined using a numerically simulated 12‐story coupled shear wall structure. It is then applied to analyze the experiments regarding the damage condition of RC shear walls under earthquakes. Results show that the proposed damage index can track the damage states of RC shear walls under seismic excitations. Analysis suggests that the proposed damage index could trace and distinguish the progression of shear and flexural damages, which potentially supports the post‐earthquake structural safety management. [ABSTRACT FROM AUTHOR]

Objective To investigate the clinical characteristics of salivary gland tumors and their pathological types.Methods Data from 2 456 patients with salivary gland tumors diagnosed between January 1973 and December 2018 at Sun Yat-sen Memorial Hospital of Sun Yat-sen University were collected, and their gender, age and tumor pathological type, location, and benign and malignant composition ratios were retrospectively analyzed.Results Over the 46-year study period, 2 456 patients with salivary gland tumors were treated; 41.9% were female, and 58.1% were male. The peak incidence was found among the 40 to 60 years of age group, in which 593 (24.1%) patients had malignant tumors and 1 863 (75.9%) had benign tumors. The ratio of benign and malignant tumors was 3.1∶1. The top two most common benign tumors were pleomorphic adenoma (58.7%) and Warthin tumors (33.6%). The top two most common malignant tumors were mucoepidermoid carcinoma (27.7%) and adenoid cystic carcinoma (26.1%). The most common sites of benign pleomorphic adenomas were the parotid glands, palate, and submandibular glands. Mucinous epidermoid carcinomas in malignant tumors were common in the parotid glands and small salivary glands. The incidence of salivary gland tumors in this group has increased each year, and this group accounted for 53.3% of the total cases over the past 10 years.Conclusion The number of patients with salivary gland tumors is increasing each year. The total incidence of salivary gland tumors is higher in men than in women. Large salivary gland tumors are mainly benign tumors, and small salivary gland tumors are more common. Polymorphic adenomas, Warthin tumors, and mucoepidermoid carcinomas are the most common tumor types; patients 40~60 years old are most likely to have benign salivary glands and have a high incidence of malignant tumors.