Abstract
We herein report a method for the synthesis of 1,4‐dicarbonyl compounds using light‐activated electron donor‐acceptor (EDA) complexes. This multi‐component reaction involves the ...photoactivation of EDA complexes formed by carboxylic acid derivatives, triphenylphosphine, and sodium iodide, resulting in single‐electron reduction. The subsequent decarboxylation fragmentation leads to the formation of nucleophilic alkyl free radicals, which can undergo sequential radical coupling reactions with electron‐deficient and electron‐rich olefins. This method has been successfully applied to various aliphatic carboxylic acid derivatives, including tertiary, secondary, and primary ones, as well as multiple types of electron‐deficient olefins and enol silyl ethers. The entire process is conducted under mild conditions, indicating its potential for the synthesis of valuable synthetic compounds.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
•Effect of composition on structures and physical properties of Ge-Sb-Se glasses.•Ge-Sb-Se glasses show a transition in the chemically stoichiometric composition.•The transition behaviors are related ...to demixing of the Ge-Sb-Se glassy network.•Synchrotron X-ray powder diffraction spectra exhibited structural parameters.•High Vis–NIR and IR transmittance and wide transmission range were discussed.
Four groups of Ge-Sb-Se chalcogenide glasses with compositions of GexSb10Se90-x (10 ≤ x ≤ 32.5), GexSb15Se85-x (5 ≤ x ≤ 27.5), GexSb20Se80-x (5 ≤ x ≤ 25), and Ge12.5SbxSe87.5-x (5 ≤ x ≤ 25) were prepared to systematically study their structural, thermal, and optical properties over a very wide compositional range. The structures, densities, glass transition temperatures, refractive indices, Vis–NIR and IR transmission spectra of the Ge-Sb-Se glasses show strikingly similar transitional features in the stoichiometric compositions. The transition behaviors of the structural, thermal, and optical properties of the Ge-Sb-Se glasses can be ascribed to the ‘demixing’ of the glassy network above the stoichiometric compositions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We developed metal- and photosensitizer-free cross-dehydrogenative coupling (CDC) systems to promote the cleavage of strong C(sp
3
)H bonds through a distinct non-photoredox engaged hydrogen atom ...transfer (HAT) process. Mechanistic experiments indicate that this reaction predominantly proceeds through an energy transfer mechanism from excited-state heteroarenes to peroxides, with the direct irradiation of peroxides serving as a supplementary and secondary pathway to promote homolysis of the OO bond. The resulting oxygen radicals undergo HAT from a substrate C-H bond, followed by addition of the obtained alky radical to heteroarenes, facilitating the formation of the key C-C bond. The conclusion that
tert
-butyl peroxybenzoate (TBPB) and heteroarenes are the optimal energy transfer pairs was drawn by screening a series of peroxides. In addition to its efficiency and step-economy, this approach boasts environmental advantages, making it suitable for the late-stage functionalization of pharmaceuticals and drug-like molecules, while accommodating a wide range of functional groups.
This study introduces a novel, eco-friendly method for Minisci alkylation without harmful catalysts, advancing sustainable pharmaceutical synthesis through energy transfer from heteroarenes to peroxide, offering significant environmental benefits.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In order to adapt to the changing and personalized market demand, the traditional single-type mass production manufacturing mode is gradually changing to multi-species small batch personalized custom ...production, flexible manufacturing in machinery manufacturing occupies an increasingly important position. However, complexity, uncertainty, multi-objective and multi-constraints are the problems faced by production scheduling in flexible manufacturing workshop, which restricts the intelligent transformation of enterprises. This paper takes an assembly shop as the research object, and carries out research on assembly line balancing and multi-automatic guided vehicle (AGV) scheduling problems in shop production. Firstly, for the multi-objective assembly line balancing problem with fluctuating demand, the relevant assembly line model is established by changing only the number of workstations and replanning the boundary, and an improved multi-objective whale optimization algorithm is proposed to reduce the rebalancing cost of the assembly line. Secondly, the multi-AGV dynamic scheduling problem with corresponding scheduling objective weights according to the current number of AGVs is analyzed, and a mathematical model is established to maximize the value of the objective function by considering a variety of factors under the premise of meeting the production requirements of the assembly line. Then, a scheduling rule selection method based on neural network and knowledge base is proposed to determine the optimal combination of scheduling rules for different system states. Finally, a simulation analysis of an assembly workshop example is carried out to verify the feasibility and effectiveness of the proposed method in solving the assembly line balancing problem and the multi-AGV scheduling problem, which improves the manufacturing efficiency and the resilience of the workshop.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Allergic diseases, which include asthma, allergic rhinitis (AR), chronic rhinosinusitis (CRS), atopic dermatitis (AD), food allergy (FA), allergic keratoconjunctivitis, seriously affect the quality ...of life of people all over the world. Recently, interleukin-33 (IL-33) has been found to play an important role in these refractory disorders, mainly by inducing T helper (Th) 2 immune responses. This article reviews the mobilization and biological function of IL-33 in allergic disorders, providing novel insights for addressing these hypersensitive conditions.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Photobiogeochemical reactions involving metal species can be a source of naturally occurring nanoscale materials in the aquatic environment. This study demonstrates that, under simulated sunlight ...exposure, ionic Ag is photoreduced in river water or synthetic natural water samples that contain natural organic matter (NOM), forming Ag nanoparticles (AgNPs) that transform in size and shape and precipitate out upon extended irradiation. We show that the dissolved oxygen concentration does not appear to affect AgNP formation rates, indicating that reactive transients such as superoxide, hydrated electron, and triplet NOM do not play a large role. By varying pH and NOM concentrations and adding competing cations on the AgNP formation, we present three lines of evidence to show that Ag ion photoreduction likely involves ionic Ag binding to NOM. Our work suggests that photochemical reactions involving ionic Ag and NOM can be a source of nanosized Ag in the environment.
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IJS, KILJ, NUK, PNG, UL, UM
Ferroptosis is a form of regulated cell death triggered by lipid peroxidation after inhibition of the cystine/glutamate antiporter system Xc–. However, key regulators of system Xc– activity in ...ferroptosis remain undefined. Here, we show that BECN1 plays a hitherto unsuspected role in promoting ferroptosis through directly blocking system Xc– activity via binding to its core component, SLC7A11 (solute carrier family 7 member 11). Knockdown of BECN1 by shRNA inhibits ferroptosis induced by system Xc– inhibitors (e.g., erastin, sulfasalazine, and sorafenib), but not other ferroptosis inducers including RSL3, FIN56, and buthionine sulfoximine. Mechanistically, AMP-activated protein kinase (AMPK)-mediated phosphorylation of BECN1 at Ser90/93/96 is required for BECN1-SLC7A11 complex formation and lipid peroxidation. Inhibition of PRKAA/AMPKα by siRNA or compound C diminishes erastin-induced BECN1 phosphorylation at S93/96, BECN1-SLC7A11 complex formation, and subsequent ferroptosis. Accordingly, a BECN1 phosphorylation-defective mutant (S90,93,96A) reverses BECN1-induced lipid peroxidation and ferroptosis. Importantly, genetic and pharmacological activation of the BECN1 pathway by overexpression of the protein in tumor cells or by administration of the BECN1 activator peptide Tat-beclin 1, respectively, increases ferroptotic cancer cell death (but not apoptosis and necroptosis) in vitro and in vivo in subcutaneous and orthotopic tumor mouse models. Collectively, our work reveals that BECN1 plays a novel role in lipid peroxidation that could be exploited to improve anticancer therapy by the induction of ferroptosis.
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•BECN1 is required for system Xc–-inhibitor-induced ferroptosis•BECN1 inhibits system Xc– activity through directly binding to SLC7A11•AMPK is required for BECN1 phosphorylation in ferroptosis•BECN1 contributes to the anticancer activity of ferroptosis in vivo
Song et al. find that BECN1 promotes ferroptosis by directly blocking system Xc– activity via binding to its core component SLC7A11. This pathway is different from the previously identified function of BECN1 as a positive regulator of autophagy via directly activating PtdIns3K activity via binding to its core component PIK3C3.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The electrolytes for lithium metal batteries (LMBs) are plagued by a low Li+ transference number (T+) of conventional lithium salts and inability to form a stable solid electrolyte interphase (SEI). ...Here, we synthesized a self‐folded lithium salt, lithium 2‐2‐(2‐methoxy ethoxy)ethoxyethanesulfonyl(trifluoromethanesulfonyl) imide (LiETFSI), and comparatively studied with its structure analogue, lithium 1,1,1‐trifluoro‐N‐2‐2‐(2‐methoxyethoxy)ethoxy)ethylmethanesulfonamide (LiFEA). The special anion chemistry imparts the following new characteristics: i) In both LiFEA and LiETFSI, the ethylene oxide moiety efficiently captures Li+, resulting in a self‐folded structure and high T+ around 0.8. ii) For LiFEA, a Li−N bond (2.069 Å) is revealed by single crystal X‐ray diffraction, indicating that the FEA anion possesses a high donor number (DN) and thus an intensive interphase “self‐cleaning” function for an ultra‐thin and compact SEI. iii) Starting from LiFEA, an electron‐withdrawing sulfone group is introduced near the N atom. The distance of Li−N is tuned from 2.069 Å in LiFEA to 4.367 Å in LiETFSI. This alteration enhances ionic separation, achieves a more balanced DN, and tunes the self‐cleaning intensity for a reinforced SEI. Consequently, the fast charging/discharging capability of LMBs is progressively improved. This rationally tuned anion chemistry reshapes the interactions among Li+, anions, and solvents, presenting new prospects for advanced LMBs.
By attaching an electron‐withdrawing sulfone group near N atom, the distance of Li−N is tuned from 2.069 Å in LiFEA to 4.367 Å in LiETFSI, which enhances ionic separation degree and achieves a more balanced donor number and tuned self‐cleaning intensity for a reinforced SEI. Consequently, the fast charging/discharging capability of lithium metal batteries with this self‐folded lithium salt is progressively improved.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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