Search

A series of versatile 4-((1,1,1,3,3,3-hexafluoropropan-2-yl)oxy)pyridine intermediates have been developed to efficiently produce biaryls, amines, ethers, and thioethers. These hydrolysis-stable ether intermediates exhibit reactivity toward electron-donating groups and nucleophiles in cross-coupling and nucleophilic substitution reactions while surpassing the stability of corresponding aryl halides. In comparison to conventional coupling methods, this protocol offers an alternative pathway for accessing natural product and drug-like compounds without the need for metal catalysts. With assistance of this approach, we successfully obtained a potent P-glycoprotein inhibitor 4k(YS-370), a potent epidermal growth factor receptor inhibitor 4l(YS-363), and a promising lysine-specific demethylase 1 inhibitor 5g.

DCN1, a critical co-E3 ligase during the neddylation process, is overactivated in many diseases, such as cancers, heart failure as well as fibrotic diseases, and has been regarded as a new target for drug development. Herein, we designed and synthesized a new class of 1,2,4-triazole-3-thione-based DCN1 inhibitors based the hit HD1identified from high-throughput screening and optimized through numerous structure–activity-relationship (SAR) explorations. HD2(IC50= 2.96 nM) was finally identified and represented a highly potent and selective DCN1 inhibitor with favorable PK properties and low toxicity. Amazingly, HD2effectively relieved Ang II/TGFβ-induced cardiac fibroblast activation in vitro, and reduced ISO-induced cardiac fibrosis as well as remodeling in vivo, which was linked to the inhibition of cullin 3 neddylation and its substrate Nrf2 accumulation. Our findings unveil a novel 1,2,4-triazole-3-thione-based derivative HD2, which can be recognized as a promising lead compound targeting DCN1 for cardiac fibrosis and remodeling.

Cardiotoxicity associated with chemotherapy has gradually become the major cause of death in cancer patients. The development of bifunctional drugs with both cardioprotective and antitumor effects has become the future direction. HDAC6 plays important roles in the progression, treatment, and prognosis of cancer and cardiovascular diseases, but bifunctional inhibitors have not been reported. Herein, structure–activity relationship studies driven by pharmacophore-based remodification and fragment-based design were performed to yield highly potent HDAC6 inhibitor I-c4containing imidazo[1,2-a]pyridine. Importantly, I-c4effectively suppressed the growth of MGC-803 xenografts in vitro and in vivo by inhibiting the deacetylation pathway without causing myocardial damage after long-term administration. Meanwhile, I-c4could mitigate severe myocardial damage against H2O2or myocardial ischemia/reperfusion in vitro and in vivo. Further studies revealed that the cardioprotective effect of I-c4was associated with reduction of inflammatory cytokines. Taken together, I-c4may represent a novel lead compound for further development of an anticarcinogen with a cardioprotective effect.

The straightness control of the working face is the key technology to realize intelligent production of coal mines. However, the discontinuity of on–off hydraulic components of the existing underground working face cannot meet the needs of intelligent straightness control. A new type of dual-spool high water-based digital valve with a motor ball screw as the driving element is proposed as a solution to this problem. In this paper, the force of the valve is firstly analyzed, and it is found that the force of the movement of the valve core can be equivalent to the disturbance of the motor. The control of the valve core is essentially displacement control. In addition, a mathematical model of the valve is established, and sliding mode control with a high-gain observer is proposed to overcome time-varying characteristics of the load. Theoretical analysis indicates that the proposed controller ensures asymptotic stability with existing uncertain disturbances. Moreover, a system based on MATLAB/Simulink simulation model is developed to further verify the performance of the proposed algorithm. Compared with traditional sliding mode control and proportional integral derivative, the proposed algorithm can still improve the tracking accuracy and robustness along with 0.05 mm error under strong time-varying interference. The valve reaches the required flow in around 0.2 s, which is sufficient for the majority of work surface application situations. The research proposes a novel design concept and control approach for straightening coal mine scraper conveyors.

By using the Crank–Nicolson method, we investigate numerically the dynamical properties of bright–bright solitons in two species Bose–Einstein condensates (BECs) trapped in an optical lattice. We confirm that the soliton splitting behavior occurs at a critical depth of optical potential. The splitting behavior of solitons and the fusion behavior of condensates can be accurately controlled by adjusting the depth and lattice parameter of optical potential, the initial amplitude and position of solitons, and the interspecies interactions. When the lattice parameter is fixed but the interspecies interaction increased exponentially with the time, each soliton splits into two soltions with different amplitude, and partial fusion of two species BECs can be found. While the interspecies interaction remains unchanged but the lattice parameter increases exponentially with the time, interestingly, the bright solitons with zero initial velocity can pass through each other and accomplish a transmission collision. Furthermore, for the case of both the interspecies interaction and lattice parameter increased exponentially with the time, a head-on collision of the bright solitons in two species BECs occurred. After the collision, each soliton splits into two soltions with equal amplitude. Meanwhile, the complete fusion of two species BECs can be observed. The relevant results can provide help for the precise manipulation of BECs experiments.

Due to high volumetric energy density, the major market share of cathode materials for lithium-ion batteries is still dominated by LiCoO2(LCO) at a 3C field. However, a number of challenges will be triggered if the charge voltage is increased from 4.2/4.3 to 4.6 V to further increase energy density, such as a violent interface reaction, Co dissolution, and release of lattice oxygen. Here, LCO is coated with the fast ionic conductor Li1.8Sc0.8Ti1.2(PO4)3(LSTP) to form LCO@LSTP, while a stable interface of LCO is in situconstructed by the decomposition of LSTP at the LSTP/LCO interface. As decomposition products of LSTP, Ti and Sc elements can be doped into LCO and thus reconstruct the interface from a layered structure to a spinel structure, which improves the stability of the interface. Moreover, Li3PO4from the decomposition of LSTP and remaining LSTP coating as a fast ionic conductor can improve Li+transport when compared with bare LCO, and thus boost the specific capacity to 185.3 mAh g–1at 1C. Benefited from the stable interface and fast ion conducting coating, the LCO@LSTP (1 wt %) cathode delivers a high capacity of 202.3 mAh g–1at the first cycle (0.5C, 3.0–4.6 V), and shows a higher capacity retention of 89.0% than LCO (50.9%) after 100 cycles. Furthermore, the change of the Fermi level obtained by using a kelvin probe force microscope (KPFM) and the oxygen band structure calculated by using density functional theory further illustrate that LSTP supports the performance of LCO. We anticipate that this study can improve the conversion efficiency of energy-storage devices.

It is well-known that the performance of BiFeO3BaTiO3(BF-BT) ceramics is sensitive to composition, calcining and sintering temperature (Tcaland Tsint) due to the formation of Bi25FeO39and/or Bi2Fe4O9impurities and/or the volatilization of Bi2O3. We report remarkably stable electrical properties over the range of −0.03 ≤ x ≤ 0.05 and 930 °C ≤ Tsint≤ 970 °C in 0.7Bi(1+x)FeO3-0.3BaTiO3ceramics prepared by one-step process. This method avoids the thermodynamically unstable region of BiFeO3and prevents the formation of Bi25FeO39and/or Bi2Fe4O9impurities even when the addition of α-Bi2O3raw material is intentionally deficient or rich to make off-stoichiometric BF-BT, thus greatly improving the robustness of compositional and processing. Rhombohedral-pseudocubic phase coexists in all ceramics, and their CR/CPCfraction are 48.0/52.0–50.6/49.4 and 55.9/44.1–56.6/43.4 when xincreases from −0.05 ≤ x ≤ 0 to 0.01 ≤ x ≤ 0.05. The stable electrical properties of d33 = 180–205 pC/N, Pr = 17.9–23.8 μC/cm2, and TC = 485–518 °C are achieved. The maximum d33T/d33RTof BF-BT is twice that of soft PZT, superior to most the-state-of-art lead-free ceramics. Our results provide a synthesis strategy for designing high performance piezoelectric materials with good stability and easy industrialization.

Steel alloys with high Mn and low C, low Cr wt.%, were designed based on the composition system for traditional high toughness, creep resistance, and longevity for high-temperature applications. In terms of energy resource utilization during production and refining, CALPHAD strategical optimization is preferable for all steel alloys. Thermo-Calc software calculates the phase diagrams α-BCC (Ferrite), and M23C6 (carbide) phases. The vital temperatures which are highlighted in this work are Ac3 (threshold temperature at which ferrite is fully transformed into austenite (α→γ)), and A4 (the threshold temperature at which austenite is fully transformed into Delta ferrite (γ→δ)) are essential for phase transformations. JMatPro software is used to predict the mechanical properties of steel alloys. The interfacial energies with regards to alloying elements for M23C6 are calculated to be between ~0.272 J/m-2 to ~0.328 J/m-2 for α-BCC) matrix, while γ-FCC has interfacial energy ranges to be between ~0.132 J/m-2 to ~0.168 J/m-2. This paper focuses on investigating the effect of alloying elements on phase transformations, interfacial energy, coarsening rate of carbides, and many other mechanical properties such as toughness at high-temperature applications using CALPHAD strategies.

Scientific analysis of excavated pottery reveals critical archaeological insights, yet data on Han Dynasty pottery remains limited. This study focuses on pottery artifacts excavated from the Daqu burial site in Beijing, renowned for their polychrome decorations and size. Utilizing optical microscopy (OM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and X-ray Fluorescence (XRF), this study examined five substrate samples sourced from fragments of pottery towers and ellipse-shaped dishes. All samples exhibited similar inclusions and the same firing atmosphere. The mineralogical analysis indicated that quartz and feldspar are predominant components, with minor constituents like chlorite and kaolinite observed in the coarse pottery of the ellipse-shaped dish. Minor mineral variations suggest differences in firing temperatures. The resemblance between low-value pottery cups and delicate polychrome towers suggests they were crafted locally. These findings advance our understanding of ceramic materials and techniques in late Eastern Han Dynasty Beijing, providing crucial insights for future studies on ancient Chinese economy and society.

Phosphate-based cathode materials such as LiFePO4(LFP) have been widely used in new energy vehicles and communication tools, due to their high stability and excellent electrochemical properties. Although many studies have demonstrated the advantages of phosphate-based cathode materials, there are still many challenges such as the low energy density, the criticism of the electrical conductivity, and the unsatisfactory low-temperature electrochemical performance to their further development. To address these challenges, many research efforts have been devoted to synthesizing and modifying phosphate-based cathode materials, and much progress has been made recently. As such, a summary of the latest research developments is needed to provide new insights into developing phosphate-based cathode materials. This review summarizes phosphate cathode materials in terms of their physicochemical properties, synthesis methods, and modifications.

Solar-driven interface evaporation recently emerges as one of the most promising methods for seawater desalination and wastewater purification, mainly due to its low energy consumption. However, there still exist special issues in the present material system based on conventional noble metals or two-dimensional (2D) nanomaterials etc., such as high costs, low light-to-heat conversion efficiencies, and unideal channels for water transport. Herein, a composite photothermal membrane based on Ti3C2TxMXene nanoflakes/copper indium selenide (CIS) nanoparticles is reported for highly efficient solar-driven interface evaporation toward water treatment applications. Results indicate that the introduction of CIS improves the spatial accessibility of the membrane by increasing the interlayer spacings and wettability of MXene nanoflakes and enhances light absorption capability as well as reduces reflection for the photothermal membrane. Simultaneously, utilization of the MXene/CIS composite membrane improves the efficiency of light-to-heat conversion probably due to formation of a Schottky junction between MXene and CIS. The highest water evaporation rate of 1.434 kgm–2h–1and a maximum water evaporation efficiency of 90.04% as well as a considerable cost-effectiveness of 62.35 g h–1/$ are achieved by using the MXene/CIS composite membrane for solar interface evaporation, which also exhibits excellent durability and light intensity adaptability. In addition, the composite photothermal membrane shows excellent impurity removal ability, e.g., >98% for salt ions, >99.8% for heavy metal ions, and ∼100% for dyes molecules. This work paves a promising avenue for the practical application of MXene in the field of water treatment.

DCN1, a co-E3 ligase, interacts with UBC12 and activates cullin–RING ligases (CRLs) by catalyzing cullin neddylation. Although DCN1 has been recognized as an important therapeutic target for human diseases, its role in the cardiovascular area remains unknown. Here, we first found that DCN1 was upregulated in isolated cardiac fibroblasts (CFs) treated by angiotensin (Ang) II and in mouse hearts after pressure overload. Then, structure-based optimizations for DCN1-UBC12 inhibitors were performed based on our previous work, yielding compound DN-2. DN-2specifically targeted DCN1 at molecular and cellular levels as shown by molecular modeling studies, HTRF, cellular thermal shift and co-immunoprecipitation assays. Importantly, DN-2effectively reversed Ang II-induced cardiac fibroblast activation, which was associated with the inhibition of cullin 3 neddylation. Our findings indicate a potentially unrecognized role of DCN1 inhibition for anticardiac fibrotic effects. DN-2may be used as a lead compound for further development.

In response to the existing problems in the prediction accuracy, data collection, real-time monitoring, and consideration of factors leading to depression in the current mechanism for predicting depression among college students, this article used computer intelligent systems to study the prediction mechanism of depression among college students. This article conducted a survey on students at University A using a survey questionnaire to understand the main reasons that affect their tendency to develop depression. It processed and analyzed the data using the Beck Depression Scale and Statistical Product and Service Solution 21.0 (SPSS 21.0). Meanwhile, natural language processing techniques in computer intelligence systems can be utilized. This article combines emotional dictionaries and word frequency-inverse document frequency to construct a prediction mechanism model for depression tendencies among college students, improving the accuracy of predicting student depression tendencies. The experiment shows that the average accuracy of the depression tendency prediction mechanism model constructed based on Natural Language Processing technology after 50 experiments was 97.02%, which was 5.33% higher than the model constructed based on neural network calculations. Overall, research on the prediction mechanism of depression tendency among college students based on computer intelligence systems can provide more effective mental health support and intervention measures for schools, helping students improve their psychological state, academic achievement, and quality of life.

Over the last decade, the roles of β-arrestins in the treatment of neuropsychological diseases have become increasingly appreciated. Fluoxetine is the first selective serotonin reuptake inhibitor developed and is approved for the clinical treatment of depression. Emerging evidence suggests that fluoxetine can directly combine with the 5-HT receptor, which is a member of the G protein-coupled receptor (GPCR) family, in addition to suppressing the serotonin transporter. In this study, we prepared a chronic mild stress (CMS)-induced depression model with β-arrestin2−/−mice and cultured adult neural stem cells (ANSCs) to investigate the involvement of the 5-HT receptor-β-arrestin axis in the pathogenesis of depression and in the therapeutic effect of fluoxetine. We found that β-arrestin2 deletion abolished the fluoxetine-mediated improvement in depression-like behaviors and monoamine neurotransmitter levels, although β-arrestin2 knockout did not aggravate CMS-induced changes in mouse behaviors and neurotransmitters. Notably, the β-arrestin2−/−mice had a shortened dendritic length and reduced dendritic spine density, as well as decreased neural precursor cells, compared to the WT mice under both basal and CMS conditions. We further found that β-arrestin2 knockout decreased the number of proliferating cells in the hippocampal dentate gyrus and suppressed the proliferative capability of ANSCs in vitro. Moreover, β-arrestin2 knockout aggravated the impairment of cell proliferation induced by corticosterone and further blocked the fluoxetine-mediated promotion of mouse hippocampal neurogenesis. Mechanistically, we found that the 5-HT2BR-β-arrestin2-PI3K/Akt axis is essential to maintain the modulation of hippocampal neurogenesis in depressed mice. Our study may provide a promising target for the development of new antidepressant drugs.

Owing to the complex environmental conditions, suspension could induce complicated forces on submarine pipelines and even cause vortex-induced vibration, resulting in fatigue damage of pipelines. Through aiming at the 28-inch submarine pipeline in the East China Sea, the pipeline was segmented according to the similarity, considering the factors of pipe assembly, typhoon, current, wave and seabed topography. The effects of span length on natural frequency in each section of submarine pipeline were analyzed by finite element model. The maximum safe span length allowed by each pipeline section was verified by fatigue cumulative damage theory, and the fatigue life of each pipeline section were predicted. The results showed that each order natural frequency of the pipeline decreased with the increase of span length. The calculated results of empirical formulas were much smaller than those of the FEM analysis. The increase of the gap between the suspended pipeline and the seabed was beneficial to enhance the fatigue life of the suspended pipeline.

In this study, a novel electrochemiluminescence (ECL) biosensor based on a CdSe@CdS quantum dot (QD)-functionalized MoS2-modified electrode was developed for the sensitive detection of mercury ions. Polycationic poly(diallyldimethylammonium chloride) (PDDA) and negatively charged QDs were adsorbed on the surface of MoS2, in sequence, to form the QD–PDDA–MoS2composites, which were employed as matrices for immobilizing thymine-rich DNA sequences (DNA1). The gold nanoparticles (AuNPs) were combined with another type of thymine-rich DNA sequences (DNA2) and glucose oxidase (GOD) to prepare the GOD–AuNP–DNA2conjugates. The composites were characterized viaUV-visible absorption spectroscopy, fluorescence and transmission electron microscopy. A thymine–Hg2+–thymine complex was formed through Hg2+mismatching with DNA1and DNA2. GOD was, therefore, modified onto the electrode surface. GOD catalyzed the reduction of dissolved oxygen by glucose to produce hydrogen peroxide, which was a co-reactant of the QDs. The electrochemiluminescence signal of the biosensor increased linearly with the increase in the Hg2+concentration over the range from 1.0 × 10−12to 1.0 × 10−6M with a detection limit of 1 × 10−13M. The reproducibility, stability and specificity of the biosensor was also studied. The biosensor was used to determine Hg2+in a real water sample and satisfactory results were obtained.

Na3V2(PO4)2F3(NVPF) with a NASICON structure has attracted widespread attention as a cathode material for sodium-ion batteries due to its stable 3d open framework, high operating voltage, and high theoretical energy density. However, this material faces limitations in practical applications due to its inherently low intrinsic electronic conductivity and the high cost of vanadium. In this study, we substituted vanadium with low-cost elements and synthesized a series of NVPF cathode materials with varying levels of Cr/Mn doping using a simple sol-gel method. The optimal NVPF-Cr/Mn1 cathode exhibits discharge specific capacities of 119.7 mAh g−1at 1C and 109.8 mAh g−1at 10C. Additionally, the discharge specific capacity of NVPF-Cr/Mn1 is 106.9 mAh g−1, with a capacity retention rate of 80 % after 400 cycles. These performance improvements are attributed to the synergistic effect of co-doping with chromium (Cr) and manganese (Mn): they expand the channels for sodium ion transport within the lattice, reduce the material's impedance and polarization, enhance the kinetics of sodium ion diffusion reactions, effectively prevent lattice distortion, and significantly improve long-term cycling performance. By strategically designing NASICON-type cathodes and employing multi-metal ion substitutions to regulate composition, we not only enhance the battery's cycle life but also contribute to reducing the cost of electrode materials. This approach opens up new possibilities for practical applications in the field of energy storage.

This paper examines the problem of fixed-time attitude tracking fault-tolerant for rigid spacecraft without angular velocity measurement, in the presence of uncertainties, external disturbances, and actuator faults. First, a fixed-time observer is established to obtain accurate estimates of the unmeasurable angular velocities, by applying a fixed-time observer, a fixed-time tracking control method is addressed to enable the tracking spacecraft to track the target spacecraft with time-varying attitude in a fixed time. A fixed-time output feedback attitude tracking controller is designed and the fixed time stability of the system is proved. In addition, the simulation results verify the effectiveness of the proposed control strategy.

Two new quaternary thioborate compounds with strongly one-dimensional growth, BaSb(BS3)S and BaBi(BS3)S, have been synthesized using the conventional solid state reaction method in closed tubes at 1100 K. The single crystal X-ray diffraction analysis has shown that compound BaSb(BS3)S crystallizes in space group Pnmaof the orthorhombic system with unit cell parameters of a= 9.6898(15) Å, b= 6.2293(13) Å, c= 11.670(2) Å, V= 704.4(2) Å3, and Z= 4, while compound BaBi(BS3)S crystallizes in space group C2/mwith unit cell parameters of a= 14.9890(17) Å, b= 6.2457(6) Å, c= 7.5591(9) Å, β = 101.604(5)°, V= 693.19(13) Å3, and Z= 4. The two compounds both crystallize in the structure of infinite one-dimensional chains with [BS3]3−trigonal plane coordination alternately bridged by [MS3]3−(M = Sb, Bi) trigonal pyramids through sharing two sulfur atoms along the crystallographic baxis. First-principles electronic structure calculations performed with the density functional theory (DFT) method show that the calculated band gaps of BaSb(BS3)S and BaBi(BS3)S are 2.29 and 2.16 eV, respectively, which are in good agreement with the experimental values estimated from UV−vis absorption spectra using the Kubelka−Munk equation, and the observed absorption peak is assigned as charge transfers from S-3p states to Sb-5p (Bi6p) states.

V5S8has received extensive attention in the field of sodium-ion batteries (SIBs) due to its two-dimensional (2D) layered structure, and weak van der Waals forces between V–S accelerate the transport of sodium ions. However, the long-term cycling of V5S8still suffers from volume expansion and low conductivity. Herein, a hollow nanotube V5S8@C (H-V5S8@C) with improved conductivity was synthesized by a solvothermal method to alleviate cracking caused by volume expansion. Benefiting from the large specific surface area of the hollow nanotube structure and uniform carbon coating, H-V5S8@C exhibits a more active site and enhanced conductivity. Meanwhile, the heterojunction formed by a few residual MoS2and the outer layer of V5S8stabilizes the structure and reduces the ion migration barrier with fast Na+transport. Specifically, the H-V5S8@C anode provides an enhanced rate performance of 270.1 mAh g–1at 15 A g–1and high cycling stability of 291.7 mAh g–1with a retention rate of 90.98% after 300 cycles at 5 A g–1. This work provides a feasible approach for the structural design of 2D layered materials, which can promote the practical application of fast-charging sodium-ion batteries.

Due to their exceptional safety profile and cost-effectiveness, aqueous zinc-ion batteries have garnered considerable interest as promising energy storage systems. Nonetheless, issues such as dendrites and interfacial side reactions limit their practical applications. Constructing anticorrosive interface is one of the effective strategies to achieve a stable Zn anode. However, it remains challenge to construct a uniform interface on Zn anode. Herein, we proposed an ultrasonic coating method to construct a thin, zincophilic and uniform layer (∼ 0.98 µm) of zinc tartrate on the zinc anode (Tar-Zn). This method can effectively remove the adsorbed H2and weakly adhered layers generated during the processing, thereby forming a defect-free and thin protective layer on the zinc anode. This Tar-Zn layer has the ability to inhibit corrosion of the zinc anode and induce uniform deposition of zinc. As a result, the lifespan of Zn anode is prolonged from 42 h to over 1300 h at 2 mA cm−2. Full cells assembled with MnO2cathode and Tar-Zn anode provide an initial capacity of 139.9 mAh g−1and an improved capacity retention of 82.7 % after 500 cycles at 1 A g−1, whereas the cells with bare Zn can only retain 65.9 % of capacity. This work provides a coating method to construct uniform layers for suppressing dendrites and side reactions.