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Six lanthanide complexes [Tb(2-NCP)2(NO3)]n (1), [Eu(2-NCP)2(3-PYC)]n (2), [Sm(2-NCP)2(3-PYC)]n (3), [Eu(2-NCP)(SA)]n (4), [Tb(2-NCP)(SA)]n (5) and [Tb(2-NCP)(AA)]n (6) (2-HNCP = 2-(2-carboxyphenyl)imidazo(4,5-f)-(1,10)phenanthroline, 3-HPYC = pyridine-3-carboxylic acid, H2SA = succinic acid, H2AA = adipic acid) have been synthesized by hydrothermal route, and the crystal structures were analyzed through elemental analysis, infrared spectroscopy, single crystal X-ray diffraction. Complexes 1 and 6 present two-dimensional (2D) layers, which are further connected to three-dimensional (3D) supramolecular architectures through C–H⋯π interactions. Complexes 2 and 3 exhibit infinite one-dimensional chains. Finally, the neighboring chains are packed by C–H⋯π interactions, giving rise to 3D supramolecular network. Complexes 4 and 5 display 2D layers, which are further extend to 3D supramolecular structures via C–H⋯O intermolecular hydrogen bonding. Six complexes possess good thermal stabilities, characteristic photoluminescence properties, and photocatalytic activities for the degradation of organic dyes under visible light irradiation. In addition, the complex 6 exhibits significantly enhanced photocatalytic activity for methylene blue, and the degradation rate could reach 81.2% in 370 min. Meanwhile trapping experiments indicated that the hole, ·O2− and ·OH are the main activated species. Furthermore, by comparing the photoluminescent and photocatalytic mutation results of same metal complexes induced by interconversion of coligands, we confirm that the properties mutation induced by coligands is much obvious and controllable.

Background: The present study aim to investigate the mechanism of Qigesan (QGS) on migration and invasion of esophageal cancer cells. Methods: First, we detected the cells in the normal group and the QGS group using microarray, and analyzed the ontology function and signaling pathway of target genes, and screened out TGF-β as one of the important targets of QGS. The subsequent verification experiments were divided into four groups: control group, model group (TGF-β1 stimulation group), QGS group (TGF-β1+QGS group) and positive control group (TGF-β1+TGF-β1 receptor inhibitor group). The migration and invasion abilities, as well as the expressions of related proteins and mRNA of each experimental group were detected. The migration and invasion ability of cells were detected by cell scratch test, and the Gene expression levels of E-cadherin, Vimentin, Smad2 and Smad7 mRNA in TGF-β1/Smad pathway were detected by RT-qPCR. The expression of E-cadherin, Vimentin, p-Smad2/3, Smad2/3 and Smad7 were detected by WB. Results: The results showed that TE-1 cells were reversed from fibroblast induced by TGF-β1 to epithelial cells after being treated QGS with the concentration of 20ug/mL for 36 h. Besides, QGS inhibited the migration and invasion of TE-1 cells and down-regulated the Gene and protein expression of Vimentin, Smad2 mRNA and Vimentin, p-Smad2/3 and Smad2/3. Meanwhile, The gene and protein overexpression E-cadherin and Smad7 was observed in QGS-treated cells. Conclusions: Together, these data indicated that QGS interfered with the epithelial-mesenchymal transition (EMT) process of TE-1 cells and reduced the migration and invasion of TE-1 cells via regulating TGF-β pathway, which maybe provided idea for the treatment of esophageal cancer.

Doping is essential in the growth of bulk Ga2O3 substrates, which could help control the electrical and optical properties to meet the requirements of various types of Ga2O3-based devices. The n type β-Ga2O3 materials with dopants including Sn, Al, Si, H et al have been successfully carried out. To further improve its conductivity and optical properties, the finding of p type β-Ga2O3 becomes very crucial. This paper reviews the efforts about such an issue with experimental and theoretical methods, describes the achievements and limitations up to now and proposes the possible research methods to achieve the p type β-Ga2O3 material.

Based on density functional theory (DFT) and first-principles method, the feasibility of using 𝛽-𝐺𝑎2𝑂3 to make vacuum ultraviolet photocathode was studied. Eight Cs adsorption sites are chosen for the 𝛽-𝐺𝑎2𝑂3(100) surface. The adsorption energy, work function, energy band structure of 8 adsorption sites and the change of work function under different Cs coverage are calculated. The results show that the adsorption energy at all sites decreases significantly. It can be concluded that the 𝛽-𝐺𝑎2𝑂3(100) surface satisfies the necessary conditions for Cs/O activation. In addition, different cesium adsorption concentrations have an effect on the surface work function, and the overall trend is that it decreases at first and then increases. Finally, the properties of energy bands under different coverage are analyzed. The results show that the widely used method of cesium adsorption to reduce the work function is also suitable for 𝛽-𝐺𝑎2𝑂3 materials.

To explore the photoemission mechanism of GaN photocathode and make clear the role played by the intrinsic gallium oxide at GaN surface, the Ga-O-Cs model was built and the properties of adsorption energies, mulliken charge distribution, work functions and density of states were calculated with the first-principle density functional theory(DFT).By calculating the surface adsorption energies of different models, we know that all the surface adsorption energies are negative, and the models are reasonable. The work function results indicate that although first connection of oxygen atom with gallium atom will lead to much higher value enhancement, while the subsequent deposition of cesium atom will achieve more decrease of work function to achieve NEA status. The calculated work functions are in good coordinate with experimental photocurrent change with different coverage. Meanwhile, the tested electron affinity variations are reasonably explained with the proposed and calculated Ga-O-Cs model. These calculations supply a theoretical evidence of the photoemission mechanism of GaN photocathodes, which would direct the following GaN and AlGaN photocathodes preparation technique.

A new coordination polymeric zinc(II) complex, namely, [Zn2(L)(H2O)3]n·nNO3 (1), (H3L = 5-(4-(tetrazol-5-yl)phenyl)isophthalic acid) has been synthesized under solvothermal conditions and structurally characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction analysis and powder X-ray diffraction. Complex 1 exhibits a three-dimensional structure with a Schlafli symbol of 44•69•82 topologies, constructed from two crystallographically independent five and six coordinated mode with metal center and connected H3L ligands. The complex has good thermal stability and excellent photoluminescent property. Furthermore, by comparing the photoluminescent and photocatalytic mutation results induced by interconversion of metal ions, we confirm that the properties mutation induced by metal ions is much controllable and obvious. In addition, the complex exhibits significantly enhanced photocatalytic activity for methylene blue (MB) under UV light irradiation (λ

Based on the excellent kinetic characteristic of the spatial cam mechanism, a kind of cam reducer is designed. First, a digital prototype of the reducer is built. Then, the multi-rigid body dynamics simulation is performed, and the driven disk motion curve and the contact force and contact torque curves are output. After verifying the correctness and feasibility of the design parameters by analyzing the simulation results, the design idea of the CAD system of the space cam reducer is established. The development of the CAD system of the space cam reducer was completed by using the Visual C++ compiler language and the secondary development tool Protoolkit. The computer aided design of the reducer is realized. Finally, the digital prototypes of spatial cam reducer are established by means of this system. It can make the design of reducer faster and easier by handing the repetitive design process and complicated calculation work to the system.

To investigate the effect of flaccidoside II on the serum uric acid levels in hyperuricemic rodents. Both mice and rats were injected intraperitoneally with potassium oxonate to induce hyperuricemia. Different dosages of flaccidoside II were orally administrated to hyperuricemic and normal rodents for 7 days, respectively. Liver xanthine oxidase (XOD) activities in hyperuricemic mice were determined using the colorimetric method. Acute toxicity of flaccidoside II was also evaluated in mice. Allopurinol, as a positive control, was administered under the same treatment scheme. The results showed that flaccidoside II (32, 16 and 8 mg/kg) could significantly lower serum uric acid levels in hyperuricemic mice. Flaccidoside II (24, 12 and 6 mg/kg) could also markedly lower serum uric acid levels in hyperuricemic rats. However, unlike allopurinol, oral administration of flaccidoside II did not produce any observable hypouricemic effect in normal animals. Flaccidoside II at the dose of 32 mg/kg significantly suppressed XOD activities in the liver of hyperuricemic mice, while at doses of 16 and 8 mg/kg flaccidoside II did not show a significant effect on XOD activities. In addition, flaccidoside II (300 mg/kg) has no or less toxicity than allopurinol in mice. These findings demonstrate that flaccidoside II exhibits anti-hyperuricemic activity in hyperuricemic animals.

In order to theoretically study the adsorption process of GaN photocathode, the adsorption model on Ga0.9375Mg0.0625N is established. Then, the adsorption energy, work function, mullikeen charge distribution and density of states on the surface of (2×2) Ga0.9375Mg0.0625N(0001)calculate are calculated by first principle on CASTEP. By comparing the adsorption energy of Cs on N atom, surface centrality and Mg atom, the result shows that adsorption is the most stable on Mg atom. The Cs/O absorption model on Mg atom is mainly researched, according to analysis the properties of different computing results for different adsorption models, it is found that they are in accordance with the changing trend of the experiment. This provides a theoretical basis for the study of the experiment.

To study the chemical constituents and biological activity of Rubus sachalinensis.The compounds in the ethyl acetate and n-butanol fraction were isolated and purified by macroporous resin,Sephadex LH-20 column chromatography,and reverse-phase preparative HPLC. The structures were identified by various spectroscopic data such as 1D,2D-NMR,HRMS. Antioxidant,anti-inflammatory and cytotoxicity of the compounds were determined by FRAP,Griess and MTT methods.Eight compounds were isolated from the ethyl acetate and n-butanol extract of Rubus sachalinensis,and identified as kaempferol-3-O-β-D-butyl glucuronate( 1),quercetin-3-O-β-D-butyl glucuronate( 2),quercetin-3-O-β-D-glucopyranoside( 3),cis-tiliroside( 4),tiliroside( 5),quercetin-3-O-β-D-ethyl glucuronate( 6),quercetin( 7) and kaempferol( 8). Activity assay showed that the compounds 1 ~ 8 had different levels of antioxidant activity,all the compounds showed cytotoxicities of IC50 greater than 200 μmol / L.Flavonoids are the main antioxidant consitituents of Rubus sachalinensis and have a good anti-inflammatory activity. All the compounds are isolated from this plant for the first time,compounds 1,2,6 are obtained from the this genus for the first time.

The methods of piezoelectric energy harvest and detection based on forced vibration are introduced in this paper. Firstly, the mechanical energy of the forced vibration is converted into alternating current energy by using the piezoelectric harvester, and then the AC currents are rectified through the full bridge rectifier circuits, and finally the capacitor filter circuits are adopted to obtain the stable DC output. It also implements the voltage waveform detection during above energy harvesting process. The experimental results show that piezoelectric oscillator has the characteristics of simple structure and support stability, and its forced vibration frequency is independent of the structural natural frequency. The piezoelectric harvester forced with the vibration source can obtain an effective energy-harvested electric output.

The aphid subfamily Hormaphidinae is a good candidate for the study of the evolution of insect – plant relationships. Most hormaphidine species depend on woody primary host plants and woody or herbaceous secondary host plants, and represent high host specificity, especially to their primary hosts. No detailed molecular phylogeny of Hormaphidinae has been reported, and the taxonomic positions of some taxa in this group remain unclear. To reconstruct major phylogenetic relationships and to understand the evolution of host association patterns for major lineages, we present the first detailed molecular phylogeny of Hormaphidinae, as inferred from nuclear and mitochondrial DNA sequences, using maximum parsimony, maximum likelihood, and Bayesian methods. The monophyly of Hormaphidinae and its three traditional tribes was supported, and a sister relationship between Hormaphidini and Nipponaphidini was suggested. Most inner relationships within tribes were also supported, and some novel relationships were revealed. Two subtribes of Cerataphidini are proposed. Divergence times estimated using a Bayesian approach indicate that tribal diversifications occurred during the Late Cretaceous and were coincident with the appearance of their primary host plants. The current pattern of secondary host association for the three tribes may have evolved in different time ranges. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165, 73–87.

All the parametric formulas in the discontinuous current mode of CCPS are given in this paper. Due to the leakage inductance and distributed capacitance existing in the high voltage high frequency transformer, the charging current decreases as the load voltage increase. To solve the issue, a dual-mode modulation strategy between pulse frequency and pulse width modulation is taken. Finally, a capacitor charging power supply of 100V input and 1600V output is designed. The experimental results confirm the correctness of the theoretical analysis and modulation strategy.