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Engine pylon emergency separation is one of the key technologies in civil aircraft design, which is difficult to obtain from abroad.Domestic researches are mainly about theories and thoughts, which cannot be applied on engineering.In this paper, the research on relationship of design loads among pylon, fuse pin and wingbox is carried out based on airworthiness standards.Load determination methods for strength calculation of interface structures is proposed through scenario analysis.The results show that the engine pylon emergency separation design only needs to consider predominantly upward loads and aft loads separately.Giving reasonable relationship of design loads among pylon, fuse pin and wingbox can reduce the weight of structures.Load directions of components connecting the pylon to the wing should be determined through scenario analysis considering structural details.

Suppressing the interfacial energy losses of the buried hole-selective layer (HSL) is essential to upgrade the power conversion efficiencies (PCEs) of inverted perovskite solar cells (PSCs). In this regard, innovations in hole-extraction materials featuring self-assembled molecule (SAM) characteristics show great potential. Herein, two SAMs of C-2PACz and S-2PACz based on phenyl- and thienyl-substituted carbazole units, respectively, were developed to serve as multifunctional HSLs. The pendant phenyl and thienyl units increase the dipole moment of the SAMs as compared to that of the standard control 2PACz, which was used to efficiently modulate the work function of ITO and form desirable energy level alignments with a perovskite absorber. C-2PACz and S-2PACz SAMs possess greater capability to passivate the interface defects of a perovskite absorber, especially S-2PACz, due to the electrostatic interaction between the under-coordinated Pb2+ and S of thiophene. C-2PACz and S-2PACz with increased conjugation also show higher conductivity to promote charge transport. Moreover, HSLs based on C-2PACz and S-2PACz form a template for the crystallization of the perovskite layer to achieve more dense and uniform crystalline grains and higher crystallinity. Owing to the above-mentioned synergistic effects, C-2PACz- and S-2PACz-derived solar cells exhibit low non-radiative recombination loss, higher PCEs and enhanced stability compared to the control device with 2PACz. [ABSTRACT FROM AUTHOR]

Despite the recent advancements in 3D object detection, the conventional 3D point cloud object detection algorithms have been found to exhibit limited accuracy for the detection of small objects. To address the challenge of poor detection of small-scale objects, this paper adopts the PointPillars algorithm as the baseline model and proposes a two-stage 3D target detection approach. As a cutting-edge solution, point cloud processing is performed using Transformer models. Additionally, a redefined attention mechanism is introduced to further enhance the detection capabilities of the algorithm. In the first stage, the algorithm uses PointPillars as the baseline model. The central concept of this algorithm is to transform the point cloud space into equal-sized columns. During the feature extraction stage, when the features from all cylinders are transformed into pseudo-images, the proposed algorithm incorporates attention mechanisms adapted from the Squeeze-and-Excitation (SE) method to emphasize and suppress feature information. Furthermore, the 2D convolution of the traditional backbone network is replaced by dynamic convolution. Concurrently, the addition of the attention mechanism further improves the feature representation ability of the network. In the second phase, the candidate frames generated in the first phase are refined using a Transformer-based approach. The proposed algorithm applies channel weighting in the decoder to enhance channel information, leading to improved detection accuracy and reduced false detections. The encoder constructs the initial point features from the candidate frames for encoding. Meanwhile, the decoder applies channel weighting to enhance the channel information, thereby improving the detection accuracy and reducing false detections. In the KITTI dataset, the experimental results verify the effectiveness of this method in small objects detection. Experimental results show that the proposed method significantly improves the detection capability of small objects compared with the baseline PointPillars. In concrete terms, in the moderate difficulty detection category, cars, pedestrians, and cyclists average precision (AP) values increased by 5.30%, 8.1%, and 10.6%, respectively. Moreover, the proposed method surpasses existing mainstream approaches in the cyclist category. [ABSTRACT FROM AUTHOR]

All-polymer solar cells (all-PSCs) show great promise for use as portable and wearable electronic power sources. It is well recognized that a gradient distribution of the two components of the active layer of all-PSCs is preferred to facilitate charge transport and suppress non-radiative recombination loss. Herein, two polymers of PBS-DIT and PTPH-DIT were designed and synthesized by changing the linking mode of a benzothiophene side chain located on a benzodithiophene (BDT) skeleton, and the influences of isomerization on the blend morphology and device performance were investigated. PBS-DIT with the BDT moiety linked to the benzene ring of benzothiophene exhibited stronger solution aggregation, better tolerance to heat processing, and finer compatibility with the acceptor of N2200. Besides, PBS-DIT induced its desirable vertical phase distribution while PTPHT-DIT was uniformly distributed over the vertical direction. Benefiting from more efficient charge transfer, higher and balanced charge transport, and less recombination loss, the all-PSCs with PBS-DIT afforded a PCE of 7.76% which is much higher than 5.31% for the blend of PTPH-DIT:N2200. The results indicate that the building block of BDT linked to the benzene ring of the benzothiophene substituent is more promising than its counterpart of BDT linked to the thiophene ring of the benzothiophene substituent. Furthermore, isomerization can be a simple yet effective method to modulate the intermolecular miscibility and vertical phase distribution. [ABSTRACT FROM AUTHOR]

Free radical initiated bicyclization of 1,6-enynes with chloralkanes, is achieved via selective activation of the C(sp3)–H bond of the chloralkane, resulting in diverse polychlorinated/chlorinated polyheterocycles. Two kinds of transformations and a scaled-up experiment were performed to test the synthetic importance of the organic chlorides. Finally, a range of radical inhibition operations and radical clock tests were explored to support the reaction process. [ABSTRACT FROM AUTHOR]

A metal-free electrochemical oxidative difluoroethylation of 2-arylbenzimidazoles was accomplished, which provided an efficient strategy for the synthesis of MeCF2-containing benzo[4,5]imidazo[2,1-a]-isoquinolin-6(5H)-ones. In addition, the method also enabled the efficient construction of various difluoroethylated indolo[2,1-a]isoquinolin-6(5H)-ones. Notably, this electrochemical synthesis protocol proceeded well under mild conditions without metal catalysts or exogenous additives/oxidants added. [ABSTRACT FROM AUTHOR]

Photo-promoted cascade cyclization of aryl alkynes with NH4SCN has been reported for the construction of diverse SCN-containing quinolino[2,1-b]quinazolinones. SCF3-containing fused cyclic compounds could also be obtained with high yields. In addition, a variety of scaled-up reactions, transformation operations, radical inhibition experiments, and on/off light studies were undertaken to support the merits and reaction mechanism of this tandem system. Finally, we confirmed the skeleton of the desired product via single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

Free-radical-promoted tandem trifluoromethylthiolation of alkenes with AgSCF3 , which provides an efficient protocol for the construction of SCF3-modified indolo[2,1- a ]isoquinolines with moderate to good yields. A series of scaled-up experiments, other substrate transformations, and radical inhibition experiments were operated to verify the merit of this reaction system. [ABSTRACT FROM AUTHOR]

Photoinduced tandem cyclization of alkynes with phenylsulfinic acids has been accomplished, which gives a mild strategy for the preparation of sulfone-substituted seven-membered N -heterocycles. A variety of scaled-up experiments, further transformations, and mechanistic studies were also operated in the follow-up work. [ABSTRACT FROM AUTHOR]

Photoinduced radical cascade cyclization of aryl acetylenes with NH4SCN was achieved, which provides a simple and mild protocol for the synthesis of SCN-containing dibenzazepines or dioxodibenzothiazepines. A variety of scaled-up operations, functional group transformations, radical capture studies and on/off light experiments were performed to test the merits of the desired products and the reaction process. [ABSTRACT FROM AUTHOR]