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Backgroup: The versatile 2-alkynylbenzamde has been reported to produce many privileged skeletons, like isoquinolin-1-ones, isocoumarin-1-imines, isoindolin-1-ones, and isobenzofuran-1-imines. Recently, we reported the projected transformation using copper salt (CuCl2) as a catalyst under O2 atmosphere. To expand the scope of reaction we used another inexpensive metal salt MnO2 as catalyst Methods: The paper aims at exploring a manganese-catalyzed reaction of 2-alkynylbenzamide under O2 balloon for the synthesis of 3-hydroxylisoquinolin-1,4-dione. Results: Results on reaction scope shows the 10 mol% MnO2 in O2 atmosphere and DCE solvent catalyzed the cyclization of 2-alkynylbenzamide to produce 3-hydroxylisoquinolin-1,4-diones in 40-68% isolated yields. The reaction proceeds through a regioselective N-center radical 6-endo-dig aza-cyclization pathway. Conclusion: We have developed a manganese-catalyzed cyclization of 2-alkynlbenzamide for the synthesis of 3-hydroxylisoquinolin-1,4-diones under O2 balloon. It is believed that the N-center radical-based 6-endo dig aza-cyclization proceeded in a regioselective manner.

This review summarizes recent advances in the use of isocyanide as “C1N1” synthons in cyclization.

To obtain crystal products with ideal morphology and better quality, it is important to fully understand and grasp the affecting mechanism of solvents on crystal morphology. In this work, the interactions between solvent/solute molecules and different crystal faces of pyriproxyfen are investigated by a combination of experiments and molecular simulations. It is found that pyriproxyfen crystals grow into a lamellar morphology in methanol and ethanol, while the crystal grows into a three-dimensional shuttle morphology in n-butanol and n-heptane. Molecular simulations reveal that the molecular arrangement of crystal faces makes the alcohol hydroxyl adsorption sites exposed in different degrees, and the (002) face is more sensitive to alcohol hydroxyl than other faces. The adsorption of alcohol hydroxyl groups hinders the growth of crystal planes, so (002) and (102) faces become the main crystal planes in methanol and ethanol, and the lamellar crystal is formed. The developed knowledge of the growth mechanism based on the interaction between the solvent and crystal interface can be conducive to the further optimization of the pyriproxyfen crystal products.

Herein, we report a highly selective fluorescent probe for the detection of Cu(ii). The detection mechanism relies on the Cu(ii)-catalyzed oxidative hydroxylation of 2-(aminocarbonyl)phenylboronic acid into salicylamide, thus recovering the excited-state intramolecular proton transfer (ESIPT) effect and inducing more than 35-fold fluorescence enhancement. The simple structure and readily available fluorescent probe give a novel method for quantitatively detecting Cu(ii) in the linear range of 0-22 μM, with a limit of detection down to 68 nM, and exhibiting high selectivity for Cu(ii) over 16 other metal ions.

Background: Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal interstitial lung disease characterized by myofibroblast accumulation and extracellular matrix deposition, which lead to irreversible damage of the lung’s architecture and the formation of fibrotic lesions. IPF is also a sequela in serious patients with the coronavirus disease 2019 (COVID-19). The molecular mechanisms under pulmonary fibrosis remain unclear, and there is no satisfactory treatment currently available. Piceatannol (PIC) is a naturally occurring resveratrol analog found in a variety of dietary sources such as grapes, passion fruit, and white tea. It has been reported to inhibit liver fibroblast growth and exhibited various antitumor activities, although its role in pulmonary fibrosis has not been established yet. In the present study, we evaluated the anti-fibrotic role of PIC in bleomycin (BLM)-induced pulmonary fibrosis in mice.Methods: Mice with BLM-induced pulmonary fibrosis were treated with PIC, and fibrotic changes were measured by hematoxylin-eosin (H&E) staining and hydroxyproline assay. Luciferase assay, Western blot assay, histological analysis, and immunofluorescence staining were used to evaluate the effect of PIC on fibroblast activation and autophagy in mouse embryonic fibroblast cells (NIH-3T3) and human lung fibroblast cells (HFL1). The anti-fibrotic mechanisms of PIC were either confirmed in vivo.Results: Our results showed that PIC significantly alleviated the bleomycin-induced collagen deposition and myofibroblast accumulation. In vitro and in vivo studies indicated that PIC plays a role in activating autophagy in the process of anti-fibroblast activation. Further mechanism studies demonstrated that PIC can promote autophagy via inhibiting the TGF-β1-Smad3/ERK/P38 signaling pathway, which leads to a decreased number of activated myofibroblasts.Conclusion: Our study demonstrated for the first time that PIC possesses the protective effects against bleomycin-induced pulmonary fibrosis due to the direct pulmonary protective effects which enhance the effect of autophagy in vitro and in vivo and finally leads to the decreased number of activated myofibroblasts. PIC may serve as a candidate compound for pulmonary fibrosis therapy and attenuates the sequelae of SARS-COV-2 pulmonary fibrosis.

In this paper, we selected Pt(en)Cl4, Pt(dach)Cl4, and Pt(bipy)Cl4 with gradually increasing ligands to explore the ligand effect on the properties of platinum(IV) anticancer drugs. The electronic structures and multiple drug properties of these three complexes were studied at the LSDA/SDD level using the density functional theory (DFT) method. By comparing the gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), electron affinity, atomic charge population, and natural bond orbital (NBO), we found that the order of reducibility is Pt(bipy)Cl4 > Pt(en)Cl4 > Pt(dach)Cl4. Our research can provide the theoretical basis for the development of anticancer drugs.

Weak dynamic disturbance caused by drilling and blasting, adjacent rockburst, and machine vibration is a key factor to rock failure/rockburst during underground excavation. Meanwhile, the propagation direction of weak dynamic disturbances varies when different underground constructions are encountered. To investigate the effect of the propagation direction of the weak dynamic disturbance on rock failure, a general true triaxial test (applying a loading state of “six stressed faces”) and a modified true triaxial test (applying a loading state of “one free face and five stressed faces”) are conducted. For the former test, Pd1 (weak dynamic disturbance along the direction of σ1), Pd2 (weak dynamic disturbance along the direction of σ2), and Pd3 (weak dynamic disturbance along the direction of σ3) are involved. For the latter test, only Pd1 and Pd2 are involved due to the limitation of the testing machine used. After testing, the rock strength and macroscopic failure characteristics of the tested specimens are systematically investigated. The experimental results indicate that the rock strength of the tested specimen without weak dynamic disturbance is higher than those with weak dynamic disturbance, indicating a reduction effect of the weak dynamic disturbance on the rock strength. Pd3 has the greatest reduction effect on rock strength due to its greatest promotion effect on crack development, while the reduction effect of Pd1 on rock strength, as well as its promotion effect on crack development, is smallest. In addition, for the tested specimens with a free face, the failure process is observed and investigated. Rockburst characterized by rock fragment ejection occurs during the testing process of these specimens. The kinetic energy of the ejected blocks without weak dynamic disturbance is higher than that with weak dynamic disturbance, showing that the weak dynamic disturbance has a reduction effect on kinetic energy. In addition, the kinetic energy of ejected blocks is lower under the Pd2 condition than that under the Pd1 condition; consequently, Pd2 has a greater influence on the kinetic energy of the ejected blocks, i.e., the intensity of rockburst.

Suitable rockburst support is critical for the prevention of rockburst disasters. In the present study, rockburst process and mechanism are investigated first in detail based on laboratory tests. It is considered that the splitting and buckling are two stages that precede the occurrence of rockburst, and buckling is the necessary prior step and precondition of rockburst. Therefore, in this study, it is proposed to use a layer of material with high tensile strength adhered to the rock surface to increase the tangential tensile strength of the surrounding rock surface and then suppress the buckling, hence achieving the purpose of suppressing the rockburst. In our experiments, cement mortar, acrylate, polyurea and basalt fabric were used to create the surface reinforcement layer. To verify the effectiveness of the proposed support strategy, true-triaxial rockburst tests were carried out, with high-speed cameras and an acoustic emission (AE) system used to monitor the failure process. The results show that increasing the surface tensile strength effectively increases the allowable buckling deformation or yielding range of rock, and the severity of rockburst reduces as the surface tensile strength increases. Characteristics of deformation, rock fragmentations and AE show that with the increase of the surface tensile strength, the internal cracking activity before the final failure is more intense, resulting in more small rock fragments formed, and more energy is consumed and dissipated in the fracturing process (continuous expansion, splitting and buckling) with the energy released in a more gradual manner and hence less kinetic energy is available to cause violent rockburst. Therefore the proposed solution is demonstrated to be an effective ground support scheme to suppress rockburst in rock excavations.

Beckmann rearrangement of ketoxime catalyzed by acidic ionic liquid-N-methyl-imidazolium hydrosulfate was studied. Rearrangement of benzophenone oxime gave the desirable product with 45% yield at 90 °C. When co-catalyst P2O5 was added, the yield could be improved to 91%. The catalyst could be reused three cycles with the same efficiency. Finally, reactions of other ketoximes were also investigated.

We report the synthesis and properties of a phthalocyanine derivative with eight fused thienyl rings and eight triisopropylsilylethynyl substituents. The fused thienyl rings were designed to enhance intermolecular interactions among the phthalocyanine molecules in the solid state whereas the triisopropylsilylethynyl substituents were aimed to improve solubility. Compared to the simple octa(2-thienyl) substituted phthalocyanine, a remarkable decrease of solubility and a 67 nm red shift in UV–visible absorption maximum were observed. The fused thienyl compound was used as a donor material in bulk heterojunction solar cells. The power conversion efficiency of 0.60% was achieved under simulated solar illumination.

Cu-BTC, one of the metal–organic frameworks (MOFs), has been applied to remove the cationic dye methylene blue (MB) and anionic dye methyl orange (CR) from contaminated water. Liquid phase adsorption experiments were conducted and the maximum adsorptive capacity was determined. Various conditions were evaluated, including initial dye concentration, contact time, solution pH, and temperature. The Langmuir and Freundlich adsorption models were used to describe the equilibrium isotherm and isotherm constant calculation. It was found that the Cu-BTC adsorption capacities of MB and CR are much higher than those of the other types of MOFs and adsorbents. Maximum equilibrium adsorption capacities of 143.27 and 877.19 mg/g for MB and CR were achieved. Three simplified kinetic models including pseudo-first-order, pseudo-second-order, and intra-particle diffusion equations were used to investigate the adsorption process. The pseudo-second-order equation was followed for adsorption of MB and CR on Cu-BTC. Te...

A new type of activated carbon, torreya-grandis-skin-based activated carbon (TAC), has been used to remove the harmful dyes (cationic dye crystal violet (CV) and anionic dye naphthol green (NG)) from contaminated water via batch adsorption. The effects of solution pH, adsorption time and temperature were studied. The Langmuir and Freundlich adsorption models were used to describe the equilibrium isotherm and isotherm constant calculation. It was found that the maximum equilibrium adsorption capacities were 292mg/g and 545mg/g for CV and NG, respectively. Adsorption kinetics was verified by pseudo-first-order, pseudo-second-order and intra-particle diffusion kinetic models. Results indicated that the rate of dye adsorption followed pseudo-second-order kinetic model for the initial dye concentration range studied. Temperature-dependent adsorption behavior of CV and NG shows that the adsorption is spontaneous and endothermic, accompanying an entropy increase. This work indicates that TAC could be employed as a low-cost alternative for the removal of the textile dyes from effluents.

A new type of metal–organic porous material (Ni/Cu–BTC) has been successfully synthesized by a solvothermal approach for the first time. The as-synthesized materials were characterized using XRD, SEM, ICP, and TGA analyses and N2 adsorption at 77 K. The Ni/Cu–BTC was applied to the adsorption of anionic dye congo red (CR) from aqueous solution, and from the experimental data, adsorption kinetics and isotherms were obtained. The results showed that a pseudo-second-order kinetic model and the Langmuir adsorption isotherm matched well for the adsorption of CR onto Ni/Cu–BTC. Thermodynamic parameters including free energy, enthalpy, and entropy of adsorption were obtained, and all the results were favorable for the adsorption. Compared with other adsorbents reported in the literature, Ni/Cu–BTC demonstrated a superior CR dye adsorption capability. The results of the present study substantiate that Ni/Cu–BTC is a promising adsorbent for the removal of the dye from wastewater.

Activated carbon derived from finger citron residue (FAC) was tested as a new type of adsorbent for the removal of harmful dyes, namely, the anionic dye methyl orange (MO) and the cationic dye methylene blue (MB), from contaminated water. Liquid-phase adsorption experiments were conducted, and the maximum adsorption capacity was determined. Various conditions were evaluated, including initial dye concentration, adsorbent dosage, contact time, solution pH, and temperature. The Langmuir and Freundlich adsorption models were used to describe the equilibrium isotherm and to calculate the isotherm constants. It was found that the adsorption capacity of FAC is much higher than those of other types of activated carbons. Maximum equilibrium adsorption capacities of 934.58 and 581.40 mg/g for MO and MB, respectively, were achieved. Three simplified kinetic models, namely, pseudo-first-order, pseudo-second-order, and intraparticle diffusion equations, were used to investigate the adsorption process. The pseudo-seco...

The Alfresco development tool is an open platform for Enterprise Content Management (ECM). In order to improve the enterprises' management efficiency in specialized industrial townships, a micro-information system based on Alfresco development tool has been proposed. This system achieves information collection, management and sharing in the development process of the enterprise. The general design ideas, system functions, system structure, key technologies and realization methods of the micro-information system are introduced in this paper. After construction of this microinformation system being completed and operated, a significant breakthrough for data management and statistics of enterprises in specialized industrial townships comes into being.

A two-year field experiment was conducted in two different locations to investigate the dissipation rate and residual fate of thiamethoxam in tobacco leaves and soil by high performance liquid chromatography with UV detection. The average recoveries for green, cured tobacco leaves and soil ranged from 89.7 %–94.8 %, 90.6 %–94.4 % and 89.0%–92.8 %, respectively, with relative standard deviations between 2.7 % and 9.2 %. The dissipation rates of thiamethoxam were described by first-order kinetics and its half-life values were in the range of 3.9–4.4 days in green tobacco leaves and 12.0–19.1 days in soil, respectively. The residue levels of thiamethoxam at harvest time ranged from 0.020–0.541 mg/kg in cured tobacco leaves, and 0.005–0.019 mg/kg in soil, respectively.

Three-Dimensional Electro-Magnetic Particle Model (3DEMPM), based on the equations of Maxwell and Newton-Lorentz, takes advantages of the Finite-Difference Time-Domain (FDTD) and Particle-In-Cell (PIC) to trace a large quantity of particles in order to gain insight into the physics of them. Although MPI alone can be used to parallelize with 1D decomposition along x-direction, the efficiency decreases with increase of CPUs because there are more communications involved. We combine MPI and OPENMP to reduce the communications in the PC cluster, one node of which shares memory with duel-core. The whole domain is decomposed into several sub-domains, the same number as the nodes. Between the nodes we use MPI to realize the communications, and inside each node the OPENMP is applied to do the parallel computing with no communication. In this way, the higher speed-up is achieved while the communication is reduced.

Using a three-dimensional full electromagnetic particle model (EMPM), we have performed global simulations of the interaction between the solar wind and the terrestrial magnetosphere, and have investigated its asymptotic stability. The distance between the dayside magnetopause subsolar point and the Earth center, R(sub mp) is measured, as the intensity of southward IMF |B(sub z)| is slowly varying. Based on the field topology theory, one analyzes the variation of R(sub mp) as a reference index of the dynamics of this interaction, when IMF |B(sub z)| successively increases and decreases to its original value. Two striking results are observed. First, as the IMF |B(sub z)| increases above a critical value, the variation of R(sub mp) suddenly changes (so called 'bifurcation' process in field topology). Above this critical value, the overall magnetic field topology changes drastically and is identified as being the signature of magnetic reconnection at the subsolar point on the magnetopause. Second, this subsolar point recovers its original location R(sub mp) by following different paths as the IMF |B(sub z)| value increases (from zero to a maximum fixed value) and decreases (from this maximum to zero) passing through some critical values. These different paths are the signature of 'hysteresis' effect, and are characteristic of the so-called 'subcritical-type' bifurcation. This hysteresis signature indicates that dissipation processes take place via an energy transfer from the solar wind to the magnetosphere by some irreversible way, which leads to a drastic change in the magnetospheric field topology. This hysteresis is interpreted herein as a consequence of the magnetic reconnection taking place at the dayside magnetopause. The field topology reveals to be a very powerful tool to analyze the signatures of three-dimensional magnetic reconnection without the obligation for determining the mechanisms responsible for, and the consequences of the reconnection on the overall magnetospheric dynamics.

We have performed benchmarks of two three-dimensional parallel Particle-In-Cell (PIC) codes that are similar but have quite different communication patterns on different computational Grids. An electrostatic code with only electrons based on the three-dimensional skeleton PIC code employs the FFT Poisson solver that uses collective communication patterns. Another is the TRISTAN (TRI-dimensional STATNford) code parallelized with MPI, an electromagnetic full particle code, which uses a field solver that only requires point-to-point neighbor communication patterns. We present the mpptest benchmarks on cluster-based computational Grids, where both the basic point-to-point communication patterns and the basic collective communication patterns used in these PIC codes are tested. The results of these benchmarks clearly allow us to quantify and understand the scalability of both communication patterns on the Grids. The present results show that the parallelized TRISTAN code (without all-to-all collective communication) is more scalable than the parallelized skeleton PIC code (with all-to-all collective communication), in cluster-based computational Grid systems where communication performances is poor.

The energy transfer from the solar wind to the Earth magnetosphere, and the cause of magnetic storms have been mysteries for decades. Axford proposed that the reconnection of magnetic field at the dayside magnetopause is one of the candidates to explain the huge energy transfer from the solar wind to the Earth magnetic field. However, the mechanism of reconnection has not been understood well in magnetospheric physics. Using a 3D full electromagnetic particle model (ENMM), we have investigated the structural stability of the Earth magnetosphere at the day-side magnetopause with a time-varying southward IMF. The distance between the magnetopause and the Earth, R/sub mp/ was measured with varying southward IMF step by step slowly. Suppose that the Earth magnetic field motion evolves according to the time-dependent equation in the general form B/sub t/=G(B,/spl lambda/). Solutions of G(B,/spl lambda/)=0 represent steady magnetic fields which we have been considering. When the parameter /spl lambda/ (IMF B/sub z/) is varied, one mean magnetic field may persist. but become unstable to small perturbations as A crosses a critical value. At such a transition point, a new magnetic field may bifurcate with breaking symmetry, which shows dissipative structures. The hysteresis in the IMF B/sub z/-R/sub mp/ plot indicates that the energy transfer system from the solar wind to the magnetosphere is dissipative, which is caused by the subcritical bifurcation. The differences of local and global steady reconnections are discussed with 3D magnetic field structures.