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Lithium-sulfur (Li-S) batteries with high theoretical specific energy are considered to be one of the highly promising next-generation energy storage systems. However, the shuttle effect of lithium polysulfides (LiPSs) and the interfacial instability of Li anodes have seriously hindered the practical application of Li-S batteries. Optimizing the electrolyte composition with additives can significantly improve the battery performance and has attracted great attention. Herein, we propose an organometallic salt, i.e., nickel bromide dimethoxyethane (NiBr2DME), as an electrolyte additive, which serves as the dual function of regulating LiPSs redox and synchronously stabilizing Li anodes. We reveal that NiBr2DME can interact with LiPSs viaNi–S and Li–Br bonds, and accelerate the mutual transformation of LiPSs, thus reducing the accumulation of LiPSs in the electrolyte. In addition, NiBr2DME can form a stable LiBr-containing interfacial layer on the Li metal surface, and promote the uniform electrodeposition of Li+ions, and inhibit the formation of Li dendrites. Thus, Li-S batteries with a concentration of 0.5 mmol L−1NiBr2DME show an initial capacity of 919.8 mAh g−1at 0.2 C, and a high capacity retention of 89.3% after 100 cycles. Even at the 4 C rate, a high discharge capacity of 602.9 mAh g−1is achieved. Surprisingly, the good cycling performance is maintained under poor electrolyte conditions with sulfur loading of 4.8 mg cm−2and electrlyte/sulfur ratio of 5 µL mg−1. This work provides a positive solution to achieve the suppression of shuttle effect, the regulation of LiPSs redox and the stabilization of Li anodes.

Herein, a new series of catalyst-controlled divergent cycloisomerizations of indole-tethered alkynes was developed utilizing readily available, versatile, and flexible N-propargyl indoles as substrates and BrettPhosAuNTf2and PtCl4as catalysts, where the chemodivergency was attributed to both the steric and electronic nature of the catalysts. A broad spectrum of N-propargyl indoles could be employed in this protocol, enabling the divergent synthesis of a library of 9H-pyrrolo[1,2-a]indoles and 4H-pyrrolo[3,2,1-ij]quinolines. Moreover, the reactions could be performed at mmol scales.

Fe nanoparticle-functionalized ordered mesoporous carbon (Fe0/OMC) was synthesized using triblock copolymers as templates and through solvent evaporation self-assembly, followed by a carbothermal reduction. Fe0/OMC had three microstructures of two-dimensional hexagonal (space group, p6mm, Fe0/OMC-1), body centered cubic (Im3̄m, Fe0/OMC-2), and face centered cubic (Fm3̄m, Fe0/OMC-3) which were controlled by simply adjusting the template. All Fe0/OMC displayed paramagnetic characteristics, with a maximum saturation magnetization of 50.1 emu·g−1. This high magnetization is advantageous for the swift extraction of the adsorbent from the solution following the adsorption process. Fe0/OMC was used as an adsorbent for the removal of silver ions (Ag(i)) from aqueous solutions, and the adsorption capacity of Fe0/OMC-1 was enhanced by the functionalization of Fe0. Adsorption property of Fe0/OMC-1 was significantly higher than that of Fe0/OMC-2 and Fe0/OMC-3, indicating that the long and straight ordered pore channels were more favorable for adsorption, and the adsorption capacity of Ag(i) on Fe0/OMC-1 was 233 mg·g−1. The adsorption process exhibited conformity with both the pseudo-second-order kinetic model and the Freundlich model, suggesting that the dominant mechanism of adsorption involved multilayer adsorption on heterogeneous surfaces.

Herein, we report the first diaryliodonium salts promoted multicomponent 1,2,3-trifunctionalization of alkynes, where both the acetylenic bond and the adjacent nonactivated propargylic C(sp3)–H bond were functionalized synergistically to generate α-arylated enones with high chemo-, regio-, and stereoselectivity. A broad spectrum of diaryliodonium salts and internal alkynes could be utilized in this protocol, and a diverse collection of highly substituted and stereochemically defined linear and cyclic complex structures could be elaborated from the enone products.

We report a comprehensive DFT study on gold-catalyzed domino cyclization to spiroindolines. The diastereoselectivity was analyzed based on the established coordination spheres. These computational results not only explain the origin of diastereoselectivity of gold-catalyzed domino cyclization but also guide the development of more effective stereochemistry of transition metal complexes controlled by a counterion effect. Detailed analysis of the key intermediates and transition states showed that the preference of the domino cyclization could be attributed to both electronic and geometric factors.

Corrosion not only causes substantial economic losses, but can also threaten personal safety. Superhydrophobic polyaniline composite anti-corrosion coating (SPANC) has closely received attention due to slowing chemical and electrochemical corrosion simultaneously, but the poor mechanical properties cannot meet actual needs. In this paper, function analysis, substance-field model and standard inventive solutions in TRIZ were used to solve the poor mechanical properties of SPANC, and a robust skeletal superhydrophobic perfluoropolysiloxane and polyaniline/epoxy resin composite coating (EPAMA-NPOS) was designed and prepared. The contact angle (CA) and sliding angle (SA) of H-SiO2@POS reach 165.0° ± 1.0 and 1.7° ± 0.03, respectively, the protection efficiency of EPAMA-NPOS reaches 99.94%, in friction test, and the CA is reduced from 165.0° to 147.0° after 310 times. The EPAMA-NPOS has achieved excellent superhydrophobicity, corrosion resistance and mechanical properties.The superhydrophobic polyaniline composite anti-corrosion coating has closely received attention due to slowing down chemical and electrochemical corrosion simultaneously, but the poor mechanical properties cannot meet actual needs, TRIZ was used to solve the poor mechanical properties, a robust skeletal superhydrophobic perfluoropolysiloxane and polyaniline/epoxy resin composite coating was prepared, which has achieved excellent superhydrophobicity, corrosion resistance and mechanical properties.

Implementing the flyby to Near-Earth Asteroids (NEAs) with the potential impact risks to the Earth allows for obtaining detailed physical parameters, thereby supporting the high-precision orbit prediction and planetary defense strategy. Different from those conducted asteroid flyby missions, in the 12th China Trajectory Optimization Competition (CTOC-12), a NEAs flyby trajectory design problem using reusable probes that depart from a Lunar Distant Retrograde Orbit (DRO) station in the cislunar space was released. The objective was flyby to as many NEAs as possible using up to 20 probes within a total of 10 years. The ∑ team proposed a solution that can explore 47 NEAs using 11 probes, ranking the first in the competition. In this paper, the methods and results from the winning team are introduced, including mission analysis and preliminary design, and low-energy transfer trajectory optimization. In particular, a round-trip trajectory is divided into three phases: deep space transfer, indirect transfer between the Earth to DRO, and DRO phasing and rendezvous. With the combination of global optimization and local optimization algorithms, the required velocity increments to change the orbital planes are effectively reduced, thus increasing the number of the explored NEAs. The final solution of our team is presented and the results are compared with those of the top three teams. The competition demonstrates that the regularization of flyby missions from the cislunar space to explore NEAs with the potential impact risks to the Earth is the feasible and promising.

A highly regio-, diastereo-, and enantioselective trimethylenemethane (TMM) cycloaddition reaction for the rapid assembly of 2-acyl-methylenecyclopentane in an atom-economic fashion is described. This intermolecular protocol allows for facile and divergent access to an array of structurally attractive cyclic adducts. The choice of a robust chiral diamidophosphite ligand, developed by our group, proved to be crucial for the success of this transformation.

The development of new methodologies that enable chemo- and stereoselective construction of fluorinated substituents, such as the trifluoromethyl (CF3) group, plays an essential role in the synthesis of new pharmaceutical agents. The exceptional ability of the CF3moiety to prevent in vivo metabolism as well as improve other pharmacological properties has led to numerous innovative strategies for installing this unique functional group. One potential yet underdeveloped approach to access these trifluoromethylated products is direct substitution of α-trifluoromethyl carbanions. Although the electron-withdrawing nature of the CF3group should facilitate deprotonation of adjacent hydrogens, the propensity of the resulting carbanions to undergo α-elimination of fluoride renders this process highly challenging. Herein, we describe a new strategy for stabilizing and utilizing transient α-trifluoromethyl carbanions that relies on a neighbouring cationic π-allyl palladium complex. These palladium-stabilized zwitterions participate in asymmetric [3 + 2] cycloadditions with a broad range of acceptors, generating valuable di- and trifluoromethylated cyclopentanes, pyrrolidines and tetrahydrofurans.

S-136 (STAVAX ESR) as a mould material has been extensively used in the optical lens manufacturing industry. In this study, the aspheric surface made of S-136 fixed by a six-degree of freedom (DOF) manipulator was polished using magnetic compound fluid (MCF) slurry. The effects of experimental parameters included rotational speed of workpiece and MCF slurry composition on surface roughness Ra and shape retention were investigated. The results demonstrated that the cutting marks on the initial surface reduced obviously under the given experimental parameters. Therefore, the smoothest surface with Ra 20 nm was obtained with MCF3 containing micro-sized Fe3O4particles with lower saturation magnetisation at nw= 1,000 rpm. The material removes uniformly during the polishing process and the Pearson correlation coefficient (Pcc) of the aspheric surface was kept above 0.994. The MCF slurry polishing was demonstrated as a potential method to smooth the S-136 aspheric surface.

Background: Alpha‐kinase 1 (ALPK1) is a master regulator in inflammation and has been proved to promote renal fibrosis by promoting the production of IL-1β in diabetic nephropathy (DN) mice. Pyroptosis is involved in high glucose (HG)-induced tubular cells injury, characterized by activation of Gasdermin D (GSDMD) and the release of IL-1β and IL-18, resulting in inflammatory injury in DN. It is reasonable to assume that ALPK1 is involved in pyroptosis-related tubular injury in DN. However, the mechanism remains poorly defined. Methods: Immunohistochemistry (IHC) staining was performed to detect the expression of pyroptosis- and fibrosis-related proteins in renal sections of DN patients and DN mice. DN models were induced through injection of streptozotocin combined with a high-fat diet. Protein levels of ALPK1, NF-κB, Caspase-1, GSDMD, IL-1β, IL-18 and α-SMA were detected by Western blot. HK-2 cells treated with high-glucose (HG) served as an in vitro model. ALPK1 small interfering RNA (siRNA) was transfected into HK-2 cells to down-regulate ALPK1. The pyroptosis rates were determined by flow cytometry. The concentrations of IL-1β and IL-18 were evaluated by ELISA kits. Immunofluorescence staining was used to observe translocation of NF-κB and GSDMD. Results: The heat map of differentially expressed genes showed that ALPK1, Caspase-1 and GSDMD were upregulated in the DN group. The expression levels of ALPK1, Caspase-1, GSDMD and CD68 were increased in renal biopsy tissues of DN patients by IHC. ALPK1expression and CD68+macrophages were positively correlated with tubular injury in DN patients. Western blot analysis showed increased expressions of ALPK1, phospho-NF-κB P65, GSDMD-NT, and IL-1β in renal tissues of DN mice and HK-2 cells, accompanied with increased renal fibrosis-related proteins (FN, α-SMA) and macrophages infiltration in interstitial areas. Inhibition of ALPK1 attenuated HG-induced upregulation expressions of NF-κB, pyroptosis-related proteins Caspase-1, GSDMD-NT, IL-1β, IL-18, α-SMA, and pyroptosis level in HK-2 cells. Also, the intensity and nuclear translocation of NF-κB and membranous translocation of GSDMD were ameliorated in HG-treated HK-2 cells after treatment with ALPK1 siRNA. Conclusions: Our data suggest that ALPK1/NF-κB pathway initiated canonical caspase-1-GSDMD pyroptosis pathway, resulting in tubular injury and interstitial inflammation of DN.

Zirconia ceramics have wide applications in the fields of aerospace, defence industry, new energy, automotive, electronics and biomedical. However, scratches, micro-cracks and sub-damage are inevitable by using conventional methods. The magnetic-assisted polishing with MCF slurry is considered as a friendly polishing method which can not only achieve smooth surface but also reduce the defects. However, the investigations on the high precision polishing of zirconia ceramics by using the MCF slurry were not conducted so far. In this work, the polishing method by using magnetic compound fluid (MCF) slurry under the rotary magnetic field was proposed for the zirconia ceramics polishing. The principle and the constructed experimental setup were presented at first. Then, the spot polishing was conducted. Finally, the effect of parameters on the finishing of work surface was investigated. Experimental results showed that zirconia ceramics workpiece could be smoothed effectively with the optimised polishing conditions.

Aberrant kinases contribute to cancer survival and proliferation. Here, we quantitatively characterized phosphoproteomic changes in an HBx-transgenic mouse model of hepatocellular carcinoma (HCC) using high-resolution mass spectrometry, profiled 22,539 phosphorylation sites on 5431 proteins. Using a strategy to interpret kinase- substrate relations in HCC and to uncover predominant kinases in tumors, our results, revealed elevated kinase activities of Src family kinases (SFKs), PKCs, MAPKs, and ROCK2 in HCC, representatives of which were further validated in cell models and clinical HBV-positive HCC samples. Inhibitor combinations targeting Src and PKCs or ROCK2 both synergized significantly to inhibit cell growth. In addition, we demonstrated that phosphorylation at Src Ser17 directly affects its kinase activity. Our phosphoproteome data facilitated the construction of a detailed molecular landscape in HCC and should serve as a resource for the cancer community. Our strategy is generally applicable to targeted therapeutics, also highlights potential mechanisms of kinase regulation.

Although the transition-metal-catalyzed vinylations of amines and alcohols via the additions to alkynes have been well developed, the selective vinylations of amino alcohols have been merely investigated. Herein, we report the gold-catalyzed divergent additions of trans-2-butene-1,4-amino alcohols’ N–H and O–H groups to alkynes. The allyl enamine and allyl vinyl ether adducts then underwent a cascade (Aza-) Claisen rearrangement/cyclization sequence, furnishing the functionalized dihydropyrrole and dihydrofuran products.

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The objective of this study is to understand pathogenesis of melamine-related kidney stone formation. We investigated the characterization of renal tubular cell under exposure to a mixture of melamine and cyanuric acid in vivo. Male Sprague-Dawley rats were separated into two experimental groups. Treatment group was administered daily with a standard commercial diet mixing with melamine and cyanuric acid, and control group was given a normal diet. Rat kidney specimens were stained with hematoxylin/eosin and the crystals were examined using a polarizing microscope. Renal tubular epithelial cells were observed by transmission electron microscopy. Semiquantitative RT-PCR assay was performed to determine monocyte chemoattractant protein-1 (MCP-1) mRNA expression, a protein in response to various proinflammatory stimuli. Apoptotic cells were examined by TUNEL assay. Melamine-associated crystals formed in glomerulus and wide renal tubule segment including proximal convoluted renal tubules, distal convoluted renal tubules, the limb loops of Henle and medullary collecting ducts in the cortex and medulla. Light microscopy results showed that the crystals lead to tubular lumen dilatation and tubular epithelial cell necrosis. It was observed that nucleus of renal tubular epithelial cells became irregular outlines and condensed, lysosomal-related structures increased, and integrity of renal tubule was deficient under electron microscopy. Apoptotic cells were noted widely in cortex and medulla. MCP-1 mRNA expression was significantly increased in the melamine and cyanuric acid-administrated group. Renal tubular epithelial cell injury, apoptosis and inflammation are involved in melamine-related kidney stone formation. Our findings are important for understanding pathogenesis of melamine-related kidney stone formation and estimating its clinical prognosis.The objective of this study is to understand pathogenesis of melamine-related kidney stone formation. We investigated the characterization of renal tubular cell under exposure to a mixture of melamine and cyanuric acid in vivo. Male Sprague-Dawley rats were separated into two experimental groups. Treatment group was administered daily with a standard commercial diet mixing with melamine and cyanuric acid, and control group was given a normal diet. Rat kidney specimens were stained with hematoxylin/eosin and the crystals were examined using a polarizing microscope. Renal tubular epithelial cells were observed by transmission electron microscopy. Semiquantitative RT-PCR assay was performed to determine monocyte chemoattractant protein-1 (MCP-1) mRNA expression, a protein in response to various proinflammatory stimuli. Apoptotic cells were examined by TUNEL assay. Melamine-associated crystals formed in glomerulus and wide renal tubule segment including proximal convoluted renal tubules, distal convoluted renal tubules, the limb loops of Henle and medullary collecting ducts in the cortex and medulla. Light microscopy results showed that the crystals lead to tubular lumen dilatation and tubular epithelial cell necrosis. It was observed that nucleus of renal tubular epithelial cells became irregular outlines and condensed, lysosomal-related structures increased, and integrity of renal tubule was deficient under electron microscopy. Apoptotic cells were noted widely in cortex and medulla. MCP-1 mRNA expression was significantly increased in the melamine and cyanuric acid-administrated group. Renal tubular epithelial cell injury, apoptosis and inflammation are involved in melamine-related kidney stone formation. Our findings are important for understanding pathogenesis of melamine-related kidney stone formation and estimating its clinical prognosis.

The molecular mechanisms underlying hepatitis B virus encoded HBx protein -mediated tumorigenesis are not fully understood. In order to gain a better view of the effects of HBx on transcriptional regulation and hepatocarcinogenesis, the expression profiles of liver and tumor tissues from 6 and 18 month-old p21-HBxtransgenic and control mice were monitored using oligo microarrays. Data analysis demonstrated that 42 genes were de-regulated in both 6 and 18 month-old HBxtransgenic mouse tissues. Gene ontology assisted analysis classified these genes into functionally related clusters that encode proteins related to metabolism, signal transduction, transcription regulation and stress responses. Among them, cytoskeletal genes, including microtubule genes tubulin-β2 (Tubb2), tubulin-β3 (Tubb3) and tubulin-β6 (Tubb6) , intermediate filament genes periplakin, keratin 8 (K8) and keratin 18 (K18) and actin-γ1 (Actg1) , were closely clustered and up-regulated in liver tissues. These results were validated by semi-quantitative RT-PCR in both mouse and human HCC tissues. The up-regulation of K8 and K18was only detected in p21-HBxbut not p21-HBsAgliver tissues, suggesting that the global change in the expression of cellular cytoskeletal genes was correlated with the expression of HBxtransgene. These findings propose for the first time that systemic dysregulation of cellular cytoskeletal genes is involved in HBx–induced hepatocarcinogenesis.

In this study, the seGVB method was implemented for the N&bond;H bonding system, specifically for hydrogen-bonded ammonia complexes, and the model well reproduces the MP2 geometries and energetics. A comparison between the ammonia dimer and water dimer is given from the viewpoint of valance-bond structures in terms of the calculated bond energies and pair–pair interactions. The linear hydrogen bond is found to be stronger than the bent bonds in both cases, with the difference in energy between the linear and cyclic structures being comparable in both cases although the N&dotbond;H bonds are generally weaker. The energy decomposition clearly demonstrates that the changes in electronic energy are quite different in the two cases due to the presence of an additional lone pair on the water molecule, and it is this effect which leads to the net stabilization of the cyclic structure for the ammonia dimer. Proton-transfer profiles for hydrogen-bonded ammonia complexes [NH2&bond;H&bond;NH2]⁻ and [NH3&bond;H&bond;NH3]⁺ were calculated. The barrier for proton transfer in [NH3&bond;H&bond;NH3]⁺ is larger than that in [NH2&bond;H&bond;NH2]⁻, but smaller than that in the protonated water dimer. The different bonding structures substantially affect the barrier to proton transfer, even though they are isoelectronic systems. ©1999 John Wiley & Sons, Inc. Int J Quant Chem 73: 357–367, 1999

Small clusters of water (H2O)n, n= 3-8, are studied using a semiempirical valence bond approach to investigate the bonding energy contribution and hydrogen-bonding structure in the most stable conformation. The energy contribution was decomposed into electron pair-pair interactions and valence-bond energy for each water monomer. Our study shows that there is significant bonding difference between small clusters (n5) of water and larger clusters (n> 5). In the larger clusters, there are structures containing tetravalent oxygen centers, which is impossible in the small clusters. The contribution to the binding energy from each H-bond varies from -4.7 kcal/mol to -7.3 kcal/mol in the water clusters considered here. The contribution of -5.9 kcal/mol per H-bond in the cubic octamer is comparable to the experimental value (-6.7 kcal/mol) of the binding energy in ice.Keywords: semi-empirical, valence bond, hydrogen bonding, water clusters.

Ab initio GVB(6/12)/6-31G** calculations were performed on A2X==YB2(A, B = H, F; X, Y = C, Si) to obtain the optimized geometries for planar and twisted singlet structures, and to also calculate pi bond energies (rotational barriers). The nature of C-C, Si-Si, and C-Si pi bonds has been investigated. The results show that the C-C pi bond energy (Epi (ethene) = 65.4 kcal/mol) decreases with increasing fluorine substitution. The pyramidalization at the carbon or silicon center for the twisted structures decreases the pi bond energies in the substituted ethenes and their silicon counterparts. The Si-Si (Epi (disilene) = 23.2 kcal/mol) and C-Si (Epi (silaethene) = 31.6 kcal/mol) pi bonds become much weaker. Fluorine substitution stabilizes both the diradical and the dipolar twisted singlet structures.Key words: pi bond energy, ab initio calculations, generalized valence bond, fluorine substitution, disilene, and silaethene.

The mechanism for thermal decarboxylation of but-3-enoic acid and its derivatives HXC=CYCH2COOH (X, Y=H, F, CH3, C2H5, and Cl) leading to carbon dioxide and olefins has been studied from the theoretical point of view by abinitioMO calculations. The transition states obtained by our abinitiocalculations are completely consistent with the experimental data, and support the "synchronous" mechanism for thermal decarboxylation of but-3-enoic acid and its derivatives via a "twisted chair" six-membered cyclic transition state. The effects of β- and γ-substituents on the activation energy (Ea) can be explained in terms of electronic charge distribution. β-Substitution decreases the activation energy, while γ-substitution increases it. Changes in the activation energy are related to changes in the charges at Cγ(C1) and Cβ(C2) as the substituents are varied. The activation energy decreases with an increase of negative charge at Cγ, while it increases with an increase of negative charge at Cβ. The best estimate of 156.8 kJ/mol for the activation energy with MP2/6-31G*//HF/3-21G(*)is in reasonable agreement with the available experimental values of 164 ± 7 kJ/mol and 160 kJ/mol for decarboxylation of but-3-enoic acid. The calculated primary kH/kD, 2.86, and 1.03, for the decarboxylation of but-3-enoic acid, are also in excellent agreement with the available experimental values of 2.7 and 1.035, respectively, supporting the transition state structure obtained.

Multiaxial fatigue of the components is a very complex behavior. This analyzes the multiaxial fatigue failure mechanism, reviews and compares the advantages and disadvantages of the classic model. The fatigue failure mechanism and fatigue life under multiaxial loading are derived through theoretical analysis and formulas, and finally verified with the results of multiaxial fatigue tests. The model of multiaxial fatigue life for low-cycle fatigue life prediction model not only improves the prediction accuracy of the classic model, but also considers the effects of non-proportional additional hardening phenomena and fatigue failure modes. The model is proved to be effective in low-cycle fatigue life prediction under different loading paths and types for different materials. Compared with the other three classical models, the proposed model has higher life prediction accuracy and good engineering applicability.

Polymer materials are widely used because of their unique properties such as light, easy processing, various performance and so on. However, due to the structural characteristics of polymer materials, some conditions such as light, heat, solvents and so on will cause polymer materials failure. In this paper, the typical failure modes and failure mechanism of polymer materials such as cracking, discoloration, bulging, precipitates and so on are analyzed and discussed.