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The fused deposition molding (FDM) process is a 3D printing molding process that has received extensive attention and research because of its free molding, strong designability and rapid prototyping. This further expands the application of continuous fiber reinforced composites. This paper reviews the forming principle, process method, equipment and printing materials of the FDM process for continuous fiber reinforced composites. The effects of process parameters, impregnation state and path planning algorithm on the mechanical properties and surface quality of 3D printed continuous fiber reinforced composite samples are analyzed. The problems encountered in the current FDM process and technology development are summarized, and suggestions for the key directions of future development are proposed.

An intermolecular annulation reaction of 2‐aryl‐1,3‐indandions with alkynes was reported using Pd(OAc)2 to access spirobi[indene]‐1,3‐diones. Under palladium catalysis, the substrates form a homocoupling dimer intermediate through a catalytic dehydrogenative cross‐coupling process. The palladium(II) species could come from dimer or 2‐aryl‐1,3‐indandion. Notably, this pathway is not typically observed in enol‐directed formal sp3 C−H functionalization/oxidative annulation palladium chemistry. This transformation provides a route to access a class of functionalized spiro carbocyclic indenes. [ABSTRACT FROM AUTHOR]

An electrochemically enabled tandem cyclization reaction of unsaturated sulfoximines with diselenides has been well developed, affording metal‐ and external oxidant‐free access to sulfoximidoyl‐based heterocycles containing selenium in moderate to good yields. With nBu4NBr as the role of catalyst and electrolyte, this methodology shows broad substrate scope and functional group tolerance under mild conditions. [ABSTRACT FROM AUTHOR]

In this paper, we propose a method that uses the idea of decoupling and unites edge information for semantic segmentation. We build a new dual-stream CNN architecture that fully considers the interaction between the body and the edge of the object, and our method significantly improves the segmentation performance of small objects and object boundaries. The dual-stream CNN architecture mainly consists of a body-stream module and an edge-stream module, which process the feature map of the segmented object into two parts with low coupling: body features and edge features. The body stream warps the image features by learning the flow-field offset, warps the body pixels toward object inner parts, completes the generation of the body features, and enhances the object's inner consistency. In the generation of edge features, the current state-of-the-art model processes information such as color, shape, and texture under a single network, which will ignore the recognition of important information. Our method separates the edge-processing branch in the network, i.e., the edge stream. The edge stream processes information in parallel with the body stream and effectively eliminates the noise of useless information by introducing a non-edge suppression layer to emphasize the importance of edge information. We validate our method on the large-scale public dataset Cityscapes, and our method greatly improves the segmentation performance of hard-to-segment objects and achieves state-of-the-art result. Notably, the method in this paper can achieve 82.6% mIoU on the Cityscapes with only fine-annotated data. [ABSTRACT FROM AUTHOR]

Millepachine, a bioactive natural product isolated from the seeds of Millettia pachycarpa, is reported to display potential antitumor activity. In this study, novel indole-containing hybrids derived from millepachine were designed, synthesized and evaluated for their antitumor activities. Among all the compounds, compound 14b exhibited the most potent cytotoxic activity against five kinds of human cancer cell lines, with IC50 values ranging from 0.022 to 0.074 μM, making it almost 100 times more active than millepachine. Valuable structure–activity relationships (SARs) were obtained. Furthermore, the mechanism studies showed that compound 14b induced cell-cycle arrest at the G2/M phase by inhibiting tubulin polymerization and further induced cell apoptosis through reactive oxygen species (ROS) accumulation and mitochondrial membrane potential (MMP) collapse. In addition, the low cytotoxicity toward normal human cells and equivalent sensitivity towards drug-resistant cells of compound 14b highlighted its potential for the development of antitumor drugs. [ABSTRACT FROM AUTHOR]

We report on the first, to the best of our knowledge, simultaneous continuous-wave red, green and blue laser operations in praseodymium-doped crystalline materials. At an absorbed pump power of 4.7 W (or 10 W of incident pump power), the maximum output power was 665 mW, which included 607 nm (red), 523 nm (green) and 479 nm (blue) three wavelengths, and the optical conversion efficiency with respect to the absorbed pump power was 14.1%. [ABSTRACT FROM AUTHOR]

The synthesis of benzothiazoles is achieved from haloanilines, sulfur powder, and quaternary ammonium salts which act as alkylation reagents as well as phase transfer catalysts in aqueous medium. [ABSTRACT FROM AUTHOR]

Optimized conditions are elaborated for the title reaction where o-iodoanilines give (significantly) higher yields compared to the o-bromoanilines. [ABSTRACT FROM AUTHOR]

• The Ru single atoms anchored N-doped rGO was obtained by an impregnation method. • The N doping defects provide favorable anchoring sites for single-atom Ru. • The in situ DEMS and DFT were performed to study the reaction process and mechanism. • The Ru single atoms offer maximized active sites for OER and ORR in Li-O 2 battery. • The Ru-N/rGO offers excellent catalytic activities for Li-O 2 batteries. The existence of defects N heteroatoms changes the surrounding coordination environment, resulting in the appearance coordinatively unsaturated sites. The N heteroatoms on rGO supports serve as "traps" to seize metal precursors Ru3+ ions and provide favorable anchoring sites for single-atom Ru. Benefited from the heteroatoms N and the evenly dispersed single-atom Ru active sites, the Ru-N/rGO offers excellent catalytic activities for OER and ORR in Li-O 2 batteries. [Display omitted] Lithium-oxygen (Li-O 2) battery is regarded as one of the potential energy storage system due to the ultra-high theoretical energy density and environmental friendliness. However, the sluggish oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) severely limited the discharge/charge efficiency. Herein, the single-atom Ru anchored N-doped reduced graphene oxide nanosheets (Ru-N/rGO) was fabricated via a simple impregnation method. When employed as cathode for Li-O 2 battery, the Ru-N/rGO delivers a higher discharge capacity, a lower overpotential and better rate performance in comparison with pure N-rGO without Ru atoms. Based on the in situ DEMS, the e-/O 2 ratio of Ru-N/rGO (2.08) is close to the theoretical value for the desired O 2 reduction to Li 2 O 2 (2.00), suggesting the discharged product is mainly Li 2 O 2. The density functional theory simulations reveal that the Ru single atoms offer high catalytic activity for OER and ORR. This work gives insight for the application of single atoms in advanced rechargeable Li-O 2 batteries. [ABSTRACT FROM AUTHOR]

Abstract: Herein we report simple Bronsted acid-mediated reactions of aldehydes with 2-vinylaniline and biphenyl-2-amine. Ultimately, the useful nitrogen-containing heterocycle derivatives are obtained. The electronic properties of the substituents on the aldehydes and 2-vinylaniline were investigated. It was found that molecules with both electron-donating and -withdrawing substituents were perfectly suitable substrates for this transformation, and the expected products were obtained in moderate to excellent yields. [Copyright &y& Elsevier]

The cyclometalated dinuclear platinum acetylide with a 9,9-dioctylfluorene spacer and two terminal triphenylamine groups has been successfully synthesized and characterized by 1 H NMR, 13 C NMR and MALDI-TOF MS. The active triphenylamine groups efficiently trigger the oxidative electropolymerization process to form a reddish-orange film on the working Pt and ITO electrodes by cyclic voltammetry. The compact film shows a polyaniline-like AC impedance behavior and an inverse dependence of AC impedance on its thickness. As a result of switching of the MLCT/ICT and dication absorption transitions between 0 and + 1.8 V, this metallopolymer film exhibits the near-IR electrochromism with significant optical contrast ratio (Δ T % = 78.3% at λ = 775 nm), comparative response time (3.8 s for the coloration step and 11.0 s for the bleaching step) and high anodic coloration efficiency ( CE = 208.3 C − 1 ·cm 2 ). [ABSTRACT FROM AUTHOR]

A series of novel phthalimide-alkylamine derivatives were synthesized and evaluated as multi-functions inhibitors for the treatment of Alzheimer’s disease (AD). The results showed that compound TM - 9 could be regarded as a balanced multi-targets active molecule. It exhibited potent and balanced inhibitory activities against ChE and MAO-B ( hu AChE, hu BuChE, and hu MAO-B with IC 50 values of 1.2 μM, 3.8 μM and 2.6 μM, respectively) with low selectivity. Both kinetic analysis of AChE inhibition and molecular modeling study suggested that TM - 9 binds simultaneously to the catalytic active site and peripheral anionic site of AChE. Interestingly, compound TM - 9 abided by Lipinski’s rule of five. Furthermore, our investigation proved that TM - 9 indicated weak cytotoxicity, and it could cross the blood-brain barrier (BBB) in vitro . The results suggest that compound TM - 9 , an interesting multi-targeted active molecule, offers an attractive starting point for further lead optimization in the drug-discovery process against Alzheimer’s disease. [ABSTRACT FROM AUTHOR]

A series of 2-acetyl-5- O -(amino-alkyl)phenol derivatives was designed, synthesized and evaluated as multi-function inhibitors for the treatment of Alzheimer’s disease (AD). The results revealed that compound TM-3 indicated selective AChE inhibitory potency ( ee AChE, IC 50  = 0.69 μM, selective index (SI) = 32.7). Both kinetic analysis of AChE inhibition and molecular modeling study suggested that TM-3 could simultaneously bind to the catalytic active site and peripheral anionic site of AChE. And TM-3 was also a highly selective MAO-B inhibitor (IC 50  = 6.8 μM). Moreover, TM-3 could act as antioxidant (ORAC value was 1.5 eq ) and neuroprotectant, as well as a selective metal chelating agent. More interestingly, compound TM-3 could cross the blood-brain barrier (BBB) in vitro and abided by Lipinski’s rule of five. Therefore, compound TM-3 , a promising multi-targeted active molecule, offers an attractive starting point for further lead optimization in the drug-discovery process against AD. [ABSTRACT FROM AUTHOR]