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In order to study the design and implementation of construction project management system-related issues. This paper designs the construction project schedule optimization system based on a hybrid genetic algorithm analyzes the requirements of the design project management system with modern system management means, constructs the system B / S structure, improves the system design function, and ensures that the construction project management system can be optimized. The design of a construction project management system can be applied in practice to realize the scientific management of engineering construction, which can not only improve the efficiency of engineering construction, but also greatly reduce the cost of project management, improve the level of engineering construction project management, and play an important role. The conclusion proves that the construction project schedule optimization system based on a hybrid genetic algorithm can effectively avoid the shortcomings of the current construction project management, improve the project management efficiency, and play a positive application value

Aniline is a mutagenic and carcinogenic material for human health, and it is desirable to construct high-performance detecting system for the trace detection of aniline. In this work, the boron (B)/nitrogen (N)-doped diamond (BND) films prepared by chemical vapor deposition are proposed as electrochemical electrodes to detect aniline in a wide concentration scale. The BND electrodes have a high sensitivity (detect limitation of 0.29 μmol L−1) and a wide linear detection range (0.5 − 500 μmol L−1). Both the detection limitation and linear range are significantly improved with respect to that from traditional electrodes of boron-doped diamond and various carbonaceous materials, which can be attributed to the synergistic effect of increased electrochemistry reduction and density of reaction sites on the BND electrode surfaces. This work develops a kind of electrochemical electrodes of B/N-doped diamond films with high performances for quantitative detections of aniline in practical applications. Supplemental data for this article is available online at http://dx.doi.org/10.1080/26941112.2021.1939170

A boron-doped diamond (BDD) has been widely used as an outstanding electrode for constructing high-performance electrochemical biosensors. In this paper, we fabricated a novel electrode combined of nanometer-sized graphite-BDD film (NG-BDD) by chemical vapor deposition. The nanometer-sized graphite (NG) is formed on the (111) facet of BDD via converting an sp3 diamond structure to an sp2 graphitic phase at high temperature in boron-rich ambient. The electrode was characterized by means of scanning electron microscopy, Raman spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. This NG-BDD was performed as an electrode of electrochemical biosensor to detect trace acetaminophen (APAP) accurately. Cyclic voltammetry and differential normal pulse voltammetry are used to investigate the overall performance of the electrochemical device. The sensor has a linear electrochemical response to APAP in the concentration range of 0.02-50 μM, and the detection limit is estimated to be as low as 5 nM. The research has resulted in a solution of constructing a reusable NG-BDD sensor to detect APAP with stability and show potential in extensive application.

In this paper, a nanopyramid boron-doped diamond (BDD) electrode is prepared by hydrogen-plasma treating conventional chemical vapor deposition BDD films. The nanopyramid grains are formed by a vaporization and secondary nucleation on BDD surface to test the trace level of an environmental hormone pollutant of 4-nonylphenol (4-NP). Voltammetry of 4-NP investigated on this electrode reveals the irreversible, adsorption-controlled, one-electron-and-one-proton involved oxidation process. The oxidation peak current is significantly evident even at low concentration of 4-NP (in the region of 1–100 nM) and the detection limit can be realized as low as 0.26 nM, which is lower than most previous reports. It is attributed to the more reaction sites provided by the high dense nanopyramids on the BDD surface and the hydrogen-terminated surface. Moreover, the electrode is reusable for the physical adsorption between 4-NP molecule and nanopyramid BDD. Taking into considering the unique properties of BDD, the corresponding electrodes show stability and specificity for detecting trace 4-NP molecules.

Two-dimensional (2D) materials with intrinsic ferromagnetism, a sizable magnetic anisotropy energy (MAE) and large spin polarization are desirable for realizing the practical spintronic applications. Base on first-principles calculations, the stability, electronic and magnetic properties of monolayer CrOBr are systematically investigated. Monolayer CrOBr is ferromagnetic semiconductor with a band gap of 1.547 eV, it possesses in-plane magnetic anisotropy with a value of −0.017 meV/formula unit (f.u.). The band gap of monolayer CrOBr can be regulated in the range of 1.547-1.145 eV by applying biaxial tensile strain. Monolayer CrOBr changes from FM state to AFM state when tensile strain increases to 8%. The MAE of monolayer CrOBr reaches a large value of −0.057 meV/f.u. at tensile strain of 8%, which is enhanced by 235% compared to that of unstrained system. The tunable MAE and electronic structure indicate that monolayer CrOBr may be a promising candidate in spintronic devices.

Two-dimensional (2D) ferromagnetic material with a sizable magnetic anisotropy energy (MAE) is crucial for exploring and developing the characteristics of spintronic devices. Using first-principles calculations, we study the electronic and magnetic properties of CoB6 monolayer. The CoB6 monolayer shows metallic ferromagnetism and exhibits in-plane magnetic anisotropy. The MAE of CoB6 monolayer is induced by Co atom, its maximum MAE is −0.181 meV/Co at θ = 90 ° ([010] direction), but minimum of −0.157 meV/Co at θ = 0 ° ([100] direction). It is worth noting that MAE of CoB6 monolayer gradually increases when tensile strain gets higher. When tensile strain increases to 8%, the maximum MAE of CoB6 monolayer is estimated to be −0.236 meV/Co at θ = 90 ° , which is enhanced by 50% compared with that of unstrained system. These results may stimulate the development of spintronic nanodevices based on 2D ferromagnetic materials.

A series of β-lactams containing the ferrocene moiety were synthesized through the Staudinger reaction between ferrocenylketene generated by the thermal Wolff rearrangement of the corresponding dia...

Ferromagnetic (FM) materials with high Curie temperature, large spin polarization ratio and large perpendicular magnetic anisotropic (PMA) are the basis of constructing practical spintronic devices. Using first-principles calculations, electronic property, magnetism and magnetic anisotropic energy (MAE) of penta-MnN2 monolayer are investigated. The calculated results indicate that penta-MnN2 monolayer is FM half-metal and exhibits PMA. The PMA is induced by Mn atom of 0.207 meV/Mn, which is one or two orders of magnitude larger than those of bulk Co (−65 μeV/atom), Fe (−1.4 μeV/atom) and Ni (2.7 μeV/atom). It is worth noting that the structure, magnetism and MAE of penta-MnN2 monolayer can be manipulated by applying biaxial strain. By applying tensile strain of 3%, penta-MnN2 monolayer has a second energy minimum and remains the original crystalline symmetry, but the N–N bond length has a sudden change. The MAE of Mn atom in penta-MnN2 monolayer can be enhanced by 21% with compressive strain compared to the unstrained systems. Meanwhile, the MAE decreases with the increase of tensile strain, and it exhibits a more significant decrease due to the sudden drop of N–N bond with tensile strain. These results may broaden the development of two-dimensional (2D) FM materials, which have potential applications in 2D spintronic nanodevices.

Based on first-principles calculations, we systematically investigate the stability, structural and electronic properties of two-dimensional (2D) hydrogenated tetragonal stanene (tetra-SnH). The calculated binding and formation energies, AIMD simulations and phonon dispersion show 2D tetra-SnH is stable. The hydrogenation also affects the electronic structure of tetragonal stanene monolayer, which is transformed from semimetal to semiconductor with a direct band gap. The optical response of 2D tetra-SnH is isotropic along the in-plane directions. Our results demonstrate that hydrogenation is an efficient way to modulate the electronic properties of tetragonal stanene, and provides a new prospect for the potential application in nanoelectronics.

In this work, we report a favorable diamond substrate to realize semiconductor surface-enhanced Raman spectroscopy (SERS) for trace molecular probes with high sensitivity, stability, reproducibility, recyclability and universality. The boron-doped diamond (BDD) with surface hydrogenation or oxygenation has matched energy levels corresponding to the target molecules and plays a critical role in achieving SERS. The enhancement factor based on BDD substrates can reach 104–105, which approaches those obtained with most nanostructured compound semiconductors and is nearly 3–4 orders of magnitude higher than those of state-of-the-art single-element semiconductors (silicon, germanium, and graphene). The mechanism of SERS is determined to be charge transfer with vibronic coupling, which could enhance the molecular polarizability tensor. Because of its unique properties such as chemical inertness, wide bandgap, modulated doping, surface functionalization, biocompatibility, and high thermal conductivity, the single-element semiconductor diamond can serve a high-performance semiconductor SERS platform with applications in broad fields.

Autophagy is an evolutionarily conserved lysosome-based degradation process. Atg5 plays a very important role in autophagosome formation. Here we show that Atg5 is required for biogenesis of late endosomes and lysosomes in an autophagy-independent manner. In Atg5 (-/-) cells, but not in other essential autophagy genes defecting cells, recycling and retrieval of late endosomal components from hybrid organelles are impaired, causing persistent hybrid organelles and defective formation of late endosomes and lysosomes. Defective retrieval of late endosomal components from hybrid organelles resulting from impaired recruitment of a component of V1-ATPase to acidic organelles blocks the pH-dependent retrieval of late endosomal components from hybrid organelles. Lowering the intracellular pH restores late endosome/lysosome biogenesis in Atg5 (-/-) cells. Our data demonstrate an unexpected role of Atg5 and shed new light on late endosome and lysosome biogenesis.