An investigation was conducted on the overall burst-instability of isolated coal pillars by means of the possibility index diagnosis method（PIDM）. First, the abutment pressure calculation model of ...the gob in side direction was established to derive the abutment pressure distribution curve of the isolated coal pillar. Second, the overall burst-instability ratio of the isolated coal pillars was defined. Finally, the PIDM was utilized to judge the possibility of overall burst-instability and recoverability of isolated coal pillars.The results show that an overall burst-instability may occur due to a large gob width or a small pillar width. If the width of the isolated coal pillar is not large enough, the shallow coal seam will be damaged at first, and then the high abutment pressure will be transferred to the deep coal seam, which may cause an overall burst-instability accident. This approach can be adopted to design widths of gobs and isolated coal pillars and to evaluate whether an existing isolated coal pillar is recoverable in skip-mining mines.
Multiple attribute group decision-making (MAGDM) methods have a significant influence on decision-making in a variety of strategic fields, including science, business and real-life studies. The ...problem of evaluation in green building energy-saving design projects could be regarded as a type of MAGDM problem. The evaluation based on distance from average solution (EDAS) method is one of the MAGDM methods, which simplifies the traditional decision-making process. Symmetry among some attributes that are known and unknown as well as between pure attribute sets and fuzzy attribute membership sets can be an effective way to solve MAGDM problems. In this paper, the classical EDAS method is extended to intuitionistic fuzzy environments to solve some MAGDM issues. First, some concepts of intuitionistic fuzzy sets (IFSs) are briefly reviewed. Then, by integrating the EDAS method with IFSs, we establish an IF-EDAS method to solve the MAGDM issues and present all calculating procedures in detail. Finally, we provide an empirical application for evaluating green building energy-saving design projects to demonstrate this novel method. Some comparative analyses are also made to show the merits of the method.
Molecular machines based on mechanically-interlocked molecules (MIMs) such as (pseudo) rotaxanes or catenates are known for their molecular-level dynamics, but promoting macro-mechanical response of ...these molecular machines or related materials is still challenging. Herein, by employing macrocyclic cucurbit8uril (CB8)-based pseudorotaxane with a pair of styrene-derived photoactive guest molecules as linking structs of uranyl node, we describe a metal-organic rotaxane compound, U-CB8-MPyVB, that is capable of delivering controllable macroscopic mechanical responses. Under light irradiation, the ladder-shape structural unit of metal-organic rotaxane chain in U-CB8-MPyVB undergoes a regioselective solid-state 2 + 2 photodimerization, and facilitates a photo-triggered single-crystal-to-single-crystal (SCSC) transformation, which even induces macroscopic photomechanical bending of individual rod-like bulk crystals. The fabrication of rotaxane-based crystalline materials with both photoresponsive microscopic and macroscopic dynamic behaviors in solid state can be promising photoactuator devices, and will have implications in emerging fields such as optomechanical microdevices and smart microrobotics.
Bundle recommendation offers users more holistic insights by recommending multiple compatible items at once. However, the intricate correlations between items, varied user preferences, and the ...pronounced data sparsity in combinations present significant challenges for bundle recommendation algorithms. Furthermore, current bundle recommendation methods fail to identify mismatched items within a given set, a process termed as “outlier item detection”. These outlier items are those with the weakest correlations within a bundle. Identifying them can aid users in refining their item combinations. While the correlation among items can predict the detection of such outliers, the adaptability of combinations might not be adequately responsive to shifts in individual items during the learning phase. This limitation can hinder the algorithm’s performance. To tackle these challenges, we introduce an encoder–decoder architecture tailored for outlier item detection. The encoder learns potential item correlations through a self-attention mechanism. Concurrently, the decoder garners efficient inference frameworks by directly assessing item anomalies. We have validated the efficacy and efficiency of our proposed algorithm using real-world datasets.
Drug–drug interactions (DDIs) are entities composed of different chemical substructures (functional groups). In existing methods that predict drug–drug interactions based on the usage of ...substructures, each node is perceived as the epicenter of a sub-pattern, and adjacent nodes eventually become centers of similar substructures, resulting in redundancy. Furthermore, the significant differences in structure and properties among compounds can lead to unrelated pairings, making it difficult to integrate information. This heterogeneity negatively affects the prediction results. In response to these challenges, we propose a drug–drug interaction prediction method based on substructure signature learning (DDI-SSL). This method extracts useful information from local subgraphs surrounding drugs and effectively utilizes substructures to assist in predicting drug side effects. Additionally, a deep clustering algorithm is used to aggregate similar substructures, allowing any individual subgraph to be reconstructed using this set of global signatures. Furthermore, we developed a layer-independent collaborative attention mechanism to model the mutual influence between drugs, generating signal strength scores for each class of drugs to mitigate noise caused by heterogeneity. Finally, we evaluated DDI-SSL on a comprehensive dataset and demonstrated improved performance in DDI prediction compared to state-of-the-art methods.
ZnO-ZnS core-shell composite rods were synthesized using a two-step facile hydrothermal methodology wherein different sulfidation durations were employed. The effects of sulfidation duration on the ...morphology and crystalline quality of ZnS shell layers on the surfaces of ZnO rods were investigated. A ZnS shell layer with visible granular features was obtained in the adequately controlled 3 h sulfidation process. A structural analysis demonstrated that the ZnS shell layers of ZnO-ZnS composite rods synthesized after 3 h sulfidation were in a well-defined crystalline cubic zinc blend phase. Moreover, optical properties revealed that these composite rods had a higher light-harvesting ability than those obtained after 1 and 2 h sulfidation. The density of surface crystal defects and the photoexcited charge separation efficiency of the composite rods were associated with changes in the microstructure of the synthesized ZnS shell layers. The optimal sulfidation duration of 3 h for the ZnO-ZnS composite rods resulted in the highest photocatalytic activity for the given photodegradation test conditions. The improved light harvesting and charge transport at the ZnO-ZnS heterointerface accounted for the enhanced photocatalytic activity of the ZnO-ZnS composite rods synthesized after 3 h sulfidation.
Polyamides are one of the most important polymers. Long-chain aliphatic polyamides could bridge the gap between traditional polyamides and polyethylenes. Here we report an approach to preparing ...sustainable ultra-strong elastomers from biomass-derived long-chain polyamides by thiol-ene addition copolymerization with diamide diene monomers. The pendant polar hydroxyl and non-polar butyrate groups between amides allow controlled programming of supramolecular hydrogen bonding and facile tuning of crystallization of polymer chains. The presence of thioether groups on the main chain can further induce metal-ligand coordination (cuprous-thioether). Unidirectional step-cycle tensile deformation has been applied to these polyamides and significantly enhances tensile strength to over 210 MPa while maintaining elasticity. Uniaxial deformation leads to a rearrangement and alignment of crystalline microstructures, which is responsible for the mechanical enhancement. These chromophore-free polyamides are observed with strong luminescence ascribed to the effect of aggregation-induced emission (AIE), originating from the formation of amide clusters with restricted molecular motions.
The coal industry is crucial for guaranteeing China’s energy security and achieving the carbon peaking and carbon neutralization (i.e., “dual carbon”) goals. Therefore, it is imperative to formulate ...a carbon neutralization strategy for the coal industry from a top-level design perspective. Considering China’s basic national conditions and regional characteristics, this study elaborates the strategic conception of carbon neutralization of the coal industry from the aspects of development concept, expected goals, and key directions, and clarifies specific implementation paths. Specifically, the core concept is to achieve the “dual carbon” goals by both considering regional disparities and promoting regional coordination; based on an overall planning nationwide, the coal energy production, coal energy application, and new energy coupling zones should be scientifically classified, thus to realize the “dual carbon” goals by region and step. The development concept can be implemented via three stages: peak attainment, orderly optimization, and neutralization attainment, and the implementation path can be detailed as carbon emission reduction, carbon substitution, carbon sequestration, and carbon recycling. Moreover, efforts should focus on breakthroughs in the following applied technologies: intelligent and precise mining and clean and efficient utilization of coal, exploitation and utilization of coal mine gas at full concentration, pumped storage of abandoned mines, energy storage and power consumption, coupling of clean coal power with carbon capture, utilization and storage, efficiently replacing of coalbed methane with CO2, CO2 bio/chemical utilization, and green ecological restoration of mines. Relevant research can provide a pioneering and fundamental reference for the coal industry to realize the “dual carbon” goals.
Abstract The co-delivery of drug and gene has become the primary strategy in cancer and other disease therapy. To co-deliver hydrophobic drug and functional gene efficiently into tumor cells, a ...star-shaped copolymer (PP-PLLD-Arg) with a photochemical internalization effect consisting of a porphyrin (PP) core and arginine-functionalized poly( l -lysine) dendron (PLLD-Arg) arms has been designed, and used to co-deliver docetaxel (DOC) and MMP-9 shRNA plasmid for nasopharyngeal cancer therapy. It was found that PP-PLLD-Arg/MMP-9 nanocomplex showed the photo-enhanced gene transfection efficiency in vitro , and could mediate a significant reduce of MMP-9 protein expression in HNE-1 cells. For co-delivery analysis, the obtained PP-PLLD-Arg/DOC/MMP-9 complexes could induce a more significant apoptosis than DOC or MMP-9 used only, and decreased invasive capacity of HNE-1 cells. Moreover, the star-shaped copolymer exhibited better blood compatibility and lower cytotoxicity compared to PEI-25k in the hemolysis and MTT assays, and also showed a good biocompatibility in vivo . Therefore, PP-PLLD-Arg with suited irradiation is a promising non-toxic and photo-inducible effective drug and gene delivery strategy, which should be encouraged in tumor therapy.
Abstract
Metal–organic rotaxane compounds (MORCs) with supramolecular (pseudo)rotaxane motifs as main structures have inherent dynamic character, but their potential as responsive molecular machines ...is largely hampered by poor responsiveness to external stimuli. In this study, using a multi‐functionalized pseudorotaxane linker that combines two kinds of functionalities, a novel MORC,
U‐bpybc‐CB8
(U refers to uranyl, bpybc refers to 1, 1’‐bis(4‐carboxybenzyl)‐4, 4’‐bipyridinium, and CB8 is cucurbit8uril), with multi‐responsive capability that can respond to both light and thermal stimuli, is reported. The characterization, combining spectra measurements and single‐crystal X‐ray diffraction, shows that, due to the involvement of viologen‐functionalized flexible organic dicarboxylate guest molecule in the CB8‐ involved pseudorotaxane ligand, the resultant uranyl‐based MORC exhibits photochromic behavior after UV or visible light irradiation. More interestingly, it is revealed that the exceptional thermal response of
U‐bpybc‐CB8
as temperature increases from 170 to 270 K, i.e., volume expansion followed by contraction after the inflection temperature of ≈230 K, can be stemmed from the lattice flexibility of this metal–organic supramolecular network. The dual responsiveness of MORCs reported here demonstrates the potential of such supramolecular assemblies as smart molecular components like sensors and switches that respond to light irradiation or temperature changes.
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