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Wheat powdery mildew caused by Blumeria graminis f. sp. tritici ( Bgt) is one of the most serious wheat diseases in the world. Biological control is considered an environmentally safe approach to control plant diseases. Here, to develop effective biocontrol agents for controlling wheat powdery mildew, antagonistic strain XZ16-1 was isolated and identified as Bacillus subtilis based on the morphological, biochemical, and physiological characteristics and 16S rDNA sequence. The culture filtrate of B. subtilis XZ16-1 and its extracts had a significant inhibitory effect on the spore germination of Bgt. Moreover, the therapeutic and prevention efficacy of the 100% culture filtrate on wheat powdery mildew reached 81.18 and 83.72%, respectively, which was better than that of chemical fungicide triadimefon. Further antimicrobial mechanism analysis showed that the XZ16-1 culture filtrate could inhibit the development of powdery mildew spores by disrupting the cell membrane integrity, causing reductions in the mitochondrial membrane potential, and inducing the accumulation of reactive oxygen species in the spores. Biochemical detection indicated that XZ16-1 could solubilize phosphate, fix nitrogen, and produce hydrolases, lipopeptides, siderophores, and indole-3-acetic acid. Defense-related enzymes activated in wheat seedlings treated with the culture filtrate indicated that disease resistance was induced in wheat to resist pathogens. Furthermore, a 106 CFU/ml suspension of XZ16-1 increased the height, root length, fresh weight, and dry weight of wheat seedlings by 77.13, 63.46, 76.73, and 19.16%, respectively, and showed good growth-promotion properties. This study investigates the antagonistic activity and reveals the action mechanism of XZ16-1, which can provide an effective microbial agent for controlling wheat powdery mildew.

Density functional theory (DFT) and coupled cluster theory (CCSD(T)) calculations are carried out to investigate the electronic and structural properties of a series of bimetallic oxide clusters MW 2 O 9 - / 0 (M = V, Nb, Ta). Generalized Koopmans’ theorem is applied to predict the vertical detachment energies (VDEs) and simulate the photoelectron spectra (PES). Theoretical calculations at the B3LYP level yield singlet and doublet ground states for the bimetallic anionic and neutral clusters, respectively. All the clusters present the six-membered ring structures with different symmetries, except that the TaW 2 O 9 - cluster shows a chained style with a penta-coordinated tantalum atom. Spin density analyses reveal oxygen radical species in all neutral clusters, consistent with their structural characteristics. Moreover, additional calculations are performed to study the oxidation reaction of CO molecule with the W 3 O 9 + cation and the isoelectronic VW2O9 cluster, and results indicate that the introduction of vanadium at tungsten site can efficiently improve the oxidation reactivity.

To solve the problems (long transmission chain, poor reachability, complicated structure, etc.) of current electrochemical machining (ECM) machines, a small magnetic driving ECM machine was designed. The working principle of the machine is introduced, magnetic driving system and electrolyte system of the machine are designed in this paper, and strength and deformation analysis of bed is performed by ANSYS software. Drive system and transmission system working as a whole part could directly drive cathode to machine workpieces without long transmission chain. The small magnetic driving ECM machine could machine holes, curved surface, internal grooves and other complicated-shape parts with high accuracy.

Micro electrochemical machining (micro ECM) is one of the most important micro manufacturing technologies. It’s recent advancements are summerized and elaborated based on large amounts of latest research documents and its future development trends are concluded. Study shows that micro ECM with nano-scale or micron-scale will get great progress when some unsolved problems are addressed.

A new design method for surface micromachined devices is proposed to reduce process complexity and improve intuitiveness of traditional design method of mask-to-shape-to-function. In the method, solid geometric models of MEMS devices are efficiently built up by selecting 3D features from the established MEMS feature database. Mask and process flow can be automatically generated with the developed aided design system based on SolidWorks. A practical example shows that the design method can shorten design cycle and improve design success rate.

Boron oxide adsorbed on alumina (B2O3/Al2O3 ) has been found to be a new and highly efficient heterogeneous catalyst for the synthesis of β-enamino ketones and esters by the enamination of various primary and secondary amines with β-dicarbonyl compounds under solvent-free conditions. The important features of this methodology are broad substrate scope, high yield, no requirement of metal catalysts, high regio- and chemoselectivity and environmental friendliness. In addition, the catalyst could be recovered easily after the reactions and reused without evident loss of reactivity.

To enable designers to construct geometric models of MEMS devices in a straightforward environment and get mask and process flow automatically, a 3D MEMS CAD system for surface micromachined devices is proposed based on traditional design software—SolidWorks. With Application Programming Interfaces (APIs) of SolidWorks, component modules and databases of the system are developed with Visual Basic, such as geometric model design module, mask and process flow generation module, process simulation module, 3D feature database and material database. Their development method is discussed in this paper. A practical example shows that surface micromachined devices can be designed efficiently in the system without tedious fabrication process.

Density functional theory (DFT) calculations are employed to investigate the reactivity of tungsten oxide clusters towards carbon monoxide. Extensive structural searches show that all the ground-state structures of (WO3)n(+) (n = 1-4) contain an oxygen radical center with a lengthened W-O bond which is highly active in the oxidation of carbon monoxide. Energy profiles are calculated to determine the reaction mechanisms and evaluate the effect of cluster sizes. The monomer WO3(+) has the highest reactivity among the stoichiometric clusters of different sizes (WO3)n(+) (n = 1-4). The reaction mechanisms for CO with mono-nuclear stoichiometric tungsten oxide clusters with different charges (WO3(-/0/+)) are also studied to clarify the influence of charge states. Our calculated results show that the ability to oxidize CO gets weaker from WO3(+) to WO3(-) as the negative charge accumulates progressively.

Density functional theory (DFT) and coupled cluster theory (CCSD(T)) calculations are carried out to investigate the electronic and structural properties of a series of bimetallic oxide clusters MW2O9(-/0) (M=V, Nb, Ta). Generalized Koopmans' theorem is applied to predict the vertical detachment energies (VDEs) and simulate the photoelectron spectra (PES). Theoretical calculations at the B3LYP level yield singlet and doublet ground states for the bimetallic anionic and neutral clusters, respectively. All the clusters present the six-membered ring structures with different symmetries, except that the TaW2O9(-) cluster shows a chained style with a penta-coordinated tantalum atom. Spin density analyses reveal oxygen radical species in all neutral clusters, consistent with their structural characteristics. Moreover, additional calculations are performed to study the oxidation reaction of CO molecule with the W3O9(+) cation and the isoelectronic VW2O9 cluster, and results indicate that the introduction of vanadium at tungsten site can efficiently improve the oxidation reactivity.