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[C24H38N6S2], triclinic, P1‾$P\overline{1}$ (no. 2), a = 5.9953(4) Å, b = 7.6132(5) Å, c = 15.3709(10) Å, α = 82.089(5)°, β = 88.307(6)°, γ = 75.992(6)°, V = 674.24(8) Å3, Z = 1, Rgt(F) = 0.0587, wRref(F2) = 0.1516, T = 296(2) K.

Herein, chiral metal–organic frameworks (MOFs), DCF-20 and LCF-20, were utilized as matrices for both chirality transfer and energy transfer. HBT1@MOFs and HBT2@MOFs emit excitation-dependent circularly polarized luminescence (CPL) due to excited-state intramolecular proton transfer (ESIPT). HBT1/C152/NIR@MOFs exhibit full-color and white CPL. The luminescence dissymmetry factors (glum) were significantly increased, benefiting from the efficient chirality space transfer and high luminescence efficiency. [ABSTRACT FROM AUTHOR]

The aim of this paper is to explore an effective model for predicting the compressive strength of concrete using machine learning technology, as well as to interpret the model using an interpretable method, which overcomes the limitation of the unknowable prediction processes of previous machine learning models. An experimental database containing 228 samples of the compressive strength of standard cubic specimens was built in this study, and six algorithms were applied to build the predictive model. The results show that the XGBoost model has the highest prediction accuracy among all models, as the R2 of the training set and testing set are 0.982 and 0.966, respectively. Further analysis was conducted on the XGBoost model to discuss its applicability. The main steps include the following: (i) obtaining key features, (ii) obtaining trends in the evolution of features, (iii) single-sample analysis, and (iv) conducting a correlation analysis to explore methods of visualizing the variations in the factors that exert influence. The interpretability analyses on the XGBoost model show that the contribution to the compressive strength by each factor is highly in line with the conventional theory. In summary, the XGBoost model proved to be effective in predicting concrete's compressive strength. [ABSTRACT FROM AUTHOR]

Two pairs of chiral MOFs with hierarchical chiral structures were constructed through assembly of achiral AIE-type multidentate linkers and chiral camphoric acid. Non-reciprocal circularly polarized luminescence (CPL) can be observed on the macroscopic due to the coexistence of optical anisotropic and chiroptical nature. This study provides a new perspective to recognize and construct chiral crystalline materials. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The crystallization of chiral molecules is of great significance to understand the origin and evolution of hierarchical chirality and reveal the relationships between structural chirality and circularly polarized luminescence (CPL) activity. Here, we report two pairs of chiral metal–organic frameworks (MOFs) (DCF‐17/LCF‐17, DCF‐18/LCF‐18) by utilizing tetradentate ligands tetra(3‐imidazoylphenyl)ethylene (TIPE) and 4,4'‐[4',5'‐bis[4‐(4‐pyridinyl)phenyl][1,1':2',1"‐terphenyl]‐4,4"‐diyl]bis[pyridine] (TPPP) as linkers. It can be observed that the spontaneous resolution of the achiral ligands is converted into the induced resolution, and the ligands form the absolute configuration by using enantiopure camphoric acid (cam) as chiral induced reagent (CIR). As a result, the racemate MOFs can be driven to generate absolute homochiral crystallization. Another two achiral MOFs [Cd(D‐cam)(TPPP)0.5] (AF‐1, AF = achiral framework) and [Cd(L‐cam)(TPPP)0.5] (AF‐2) were prepared. The position disorder of D/L‐cam skeleton causes the generation of nonchiralization, further leading to disappearance of symmetry breaking of TPPP. For the perspective of structure, this is the first report which reveals the chiral transfer and nonchiralization between chiral induced agents and tetradentate ligands. Besides, DCF‐17 and LCF‐17 show CPL with luminescence dissymmetry factor (glum) of –1.0 × 10‐2 and +9.2 × 10–3, respectively. This work provides the useful evidences to reveal the induced chiral crystallization and the construction of CPL‐active crystalline materials. [ABSTRACT FROM AUTHOR]

The unique advantage of orbital angular momentum (OAM) provides a novel approach to breaking through the limitations of high‐capacity and long‐distance transmission in the conventional radio‐overfiber passive optical network (RoF‐PON) hybrid access network. Introducing the OAM division multiplexing (OAM‐DM) based on Laguerre–Gaussian (LG) beams into the RoF‐PON, an innovative multidimensional system architecture is proposed, which integrates with polarization‐division multiplexing (PDM), wavelength‐division multiplexing (WDM), and orthogonal frequency‐division multiplexing (OFDM) technologies. Successful long‐distance transmission of both the downstream 40 GHz radio OFDM signal and the upstream 40 Gbps on‐off keying (OOK) signal over 80 km are achieved. Additionally, at the optical network unit side, low‐cost upstream carrier re‐modulation technology and flexible access for both wired and wireless signals are realized. The proposed RoF‐OAM‐DM‐PDM‐WDM‐OFDM‐PON architecture offers a dependable solution for high‐capacity and low‐cost future communication systems, holding great importance in achieving flexible access networks. [ABSTRACT FROM AUTHOR]

Circularly polarized electroluminescence (CPEL) is an active area of research because of its wide application in 3D displays and anti‐counterfeiting. However, it is not trivial to obtain a high asymmetry factor for highly efficient CPELs. Herein, a highly efficient CPEL is demonstrated with a superior asymmetry factor by using a chiral phosphine‐oxide‐passivated perovskite film as an emitter. An in situ‐formed perovskite nanocrystalline (NC) film is obtained by passivation of the chiral phosphine oxide. The as‐formed film exhibits much‐enhanced photoluminescence compared with the pristine film. More importantly, the NC film exhibits excellent chiral photoluminescence with a luminescence dissymmetry factor glum as high as 5.6 × 10−3. Electrically driven light‐emitting diodes based on the NC film exhibited superior device performance with a maximum brightness of 18,783 cd m−2 and a peak external quantum efficiency of 3.6%. More encouragingly, an unprecedented electroluminescence asymmetry factor gEL of up to 0.18 is achieved because of the chiral lattice distortion of the perovskite, which is the state‐of‐the‐art among hybrid materials. [ABSTRACT FROM AUTHOR]

Ni/Al multilayered energetic structural composites with micron scale were prepared by electroless plating followed by hot press process. The effects of original layer thickness ratio on the microstructure, exothermic properties and mechanical properties of the fabricated composites were investigated, and then the fracture mechanism was analyzed. The results show that the interface bonding of Ni/Al multilayered energetic structural composites is perfect and the initial temperature of interface reaction increases with the increase of original layer thickness ratios. The 2/3 Ni/Al multilayered energetic structural composite not only has the highest reaction energy density of 1051.62 J/g, but also has good strength and plasticity. The tensile strength, elongation and bending strength reach 285.05 MPa, 8.87% and 309.09 MPa respectively. When the layer thickness ratio increases from 1/2 to 1/1, both the tensile strength and bending strength increase, the plasticity decreases. This is related to the composition and interfacial structure. Failure mode of Ni/Al multilayered energetic structural composite is delamination mixed with fracture, and the interface delamination gets more serious with the increase of the layer thickness ratio.

Geodynamic evolution in the late Paleozoic is significant for understanding the final amalgamation of the Central Asian Orogenic Belt (CAOB). No consensus has yet been reached regarding the late Paleozoic geodynamic evolution of the northern Great Xing'an Range (GXR) in northeastern China, the eastern CAOB. Furthermore, late Paleozoic syenogranitediabase dyke association is present in the Xiaokele area in northern GXR. It provides an important opportunity to understand the nature of magmatism and the geodynamic evolution during this period. This paper presents new zircon U-Pb ages, zircon Hf isotopic compositions, and geochemical data of whole rocks for Xiaokele syenogranite and diabase. Zircon U-Pb dating suggests that the Xiaokele syenogranite (292.5 [+ or -] 0.9 Ma) and diabase (298.3 [+ or -] 1.5 Ma) were emplaced during the early Permian. The Xiaokele syenogranites have high Si[O.sub.2] contents, low MgO contents, and enriched zircon [[epsilon].sub.Hf](t) values, suggesting that their primary magma was generated by the partial melting of the juvenile crustal material. The Xiaokele diabases have low Si[O.sub.2] contents, high MgO contents, are enriched in large-ion lithophile elements, depleted in high-field-strength elements, and exhibit enriched zircon [[epsilon].sub.Hf](t) values. They derived from a lithospheric mantle source that had previously been metasomatized by slab-derived fluids. Combined with previous research results, we believe that the continent-continent collision between the Xing'an and Songliao blocks occurred during the late early Carboniferous - early late Carboniferous (330-310 Ma), and the two blocks were transformed into a post-collisional extensional setting during the latest Carboniferous - early Permian. Key words: early Permian, syenogranite, diabase, post-collisional extensional setting, Xiaokele, northern Great Xing'an Range. L'evolution geodynamique au Paleozoique tardif est importante pour la comprehension de l'amalgamation finale de la ceinture orogenique d'Asie centrale (COAC). Aucun consensus n'a encore ete etabli quant a l'evolution geodynamique au Paleozoique tardif du Grand Xing'an (GX) septentrional de l'est de la COAC dans le nord-est de la Chine. En outre, une association d'age paleozoique tardif de syenogranite et de dykes de diabase est presente dans la region de Xiaokele du GX septentrional, qui offre une bonne occasion de mieux comprendre la nature du magmatisme et de l'evolution geodynamique durant cette periode. L'article presente de nouveaux ages U-Pb sur zircons, des donnees sur la composition des isotopes de Hf des zircons et des donnees geochimiques sur roche totale pour le syenogranite et la diabase de Xiaokele. La datation U-Pb sur zircons indiquerait que le syenogranite (292,5 [+ or -] 0,9 Ma) et la diabase (298,3 [+ or -] 1,5 Ma) de Xiaokele ont ete mis en place durant le Permien precoce. Les syenogranites de Xiaokele ont des teneurs elevees en Si[O.sub.2] et faibles MgO et presentent des valeurs enrichies de [[epsilon].sub.Hf](t) des zircons, ce qui indiquerait que leur magma primaire est un produit de la fusion partielle de materiau crustal juvenile. Les diabases de Xiaokele ont des teneurs en Si[O.sub.2] faibles et en MgO elevees et sont enrichies en elements lithophiles a grand rayon ionique, appauvries en elements a forte liaison atomique et presentent des valeurs enrichies de [[epsilon].sub.Hf](t) des zircons. Elles proviennent d'une source dans le manteau lithospherique ayant prealablement subi un metasomatisme cause par des fluides issus d'une plaque subductee. A la lumiere de ces resultats et de resultats de travaux anterieurs, nous croyons que la collision continent-continent des blocs de Xing'an et de Songliao s'est produite durant l'intervalle du Carbonifere precoce tardif au Carbonifere tardif precoce (330 Ma-310 Ma) et que les deux blocs se sont transformes en un milieu d'extension post-collision durant l'intervalle de la fin du Carbonifere au Permien precoce. [Traduit par la Redaction] Mots-cles: Permien precoce, syenogranite, diabase, milieu d'extension post-collision, Xiaokele, Grand Xing'an septentrional., Introduction The tectonic evolution of orogenic belts is characterized by changes in the associated magmatic composition (Harris et al. 1986). Post-collisional magmatism, as one of the common characteristics of many [...]