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Marketing teaching is still largely based on theoretical teaching. This kind of teaching mode is difficult to greatly improve the marketing practice teaching, students’ practical ability, innovative thinking ability, and so on. At the same time, the teaching arrangement of marketing training is not standardized, which makes it difficult to provide effective guidance for students. This paper attempted to reform the traditional teaching methods of marketing courses in universities, and deeply studied the teaching methods of traditional college students’ marketing courses under the background of the network, as well as conducted marketing practice according to two different Internet algorithm marketing strategy models. The experimental data showed that the average teaching quality score of the traditional marketing course teaching mode was only 6.9, while the teaching quality score of the marketing course teaching mode under the Internet background was 8.15; the market share of water heaters under the neural network-based marketing strategy increased by 8.1% within 4 months, while the market share of water heaters under the data mining-based marketing strategy decreased by 4.8%. Therefore, it can be seen that the marketing course teaching mode under the Internet background can improve the teaching quality, and the marketing effect of the neural network-based marketing strategy is better.

Current research has widely applied heteroatom doping for the promotion of catalyst activity in peroxymonosulfate (PMS) systems; however, the relationship between heteroatom doping and stimulated activation mechanism transformation is not fully understood. Herein, we introduce nitrogen and sulfur doping into a Co@rGO material for PMS activation to degrade tetracycline (TC) and systematically investigate how heteroatom doping transformed the activation mechanism of the original Co@rGO/PMS system. N was homogeneously inserted into the reduced graphene oxide (rGO) matrix of Co@rGO, inducing a significant increase in the degradation efficiency without affecting the activation mechanism transformation. Additionally, S doping converted Co

In this paper, to investigate the effect of loading method of pulse current on the tensile deformation behavior of AZ31B magnesium alloy sheet, the intermittent pulse current with short-time and high-frequency was introduced in uniaxial tensile tests and the influence of duty ratio and loading time of pulse current on the deformation behavior of AZ31B magnesium alloy sheet was discussed. The strain and temperature field distributions on the specimens were measured during the intermittent pulse electrically-assisted tension (IPEAT), and the microstructure and fracture morphology under different pulse current conditions were observed. Results shows appropriate pulse current parameters can effectively improve the elongation of AZ31B magnesium alloy sheet. The strain of the sample is closely related to temperature distribution. With the deformation of the sample, the temperature on the sample increases gradually and the temperature distribution is non-uniform along the tensile direction, resulting in an inhomogeneous strain distribution of the sample. In addition, grain growth and dynamic recrystallization were observed on the AZ31B magnesium alloy sheet in different degrees under intermittent pulse current. Fracture morphology analysis shows that the number of dimples and tearing edges increased on the fracture obtained under IPEAT. The microhardness analysis shows that when intermittent pulse current is applied in the tensile test, the hardness of the sheet may change. This research provides an effective idea for the forming process of magnesium alloy sheets, which can be used to form large size thin-walled sheet components, and can significantly improve the forming quality of the sheets.

Adsorbents, especially those with high removal efficiency, long life, and multi-purpose capabilities, are the most crucial components in an adsorption system. By taking advantage of the liquid-like mobility and crystal-like ordering of liquid crystal materials, a liquid crystal induction method is developed and applied to construct three-dimensional graphene-based adsorbents featuring excellent shape adaptability, a distinctive pore structure, and abundant surface functional groups. When the monoliths are used for water restoration, the large amount of residual oxygen-containing groups is more susceptible to electrophilic attack, thus contributing to cation adsorption (up to 705.4 mg g

The anisotropic deformation behavior and forming limit of hot-rolled Al/Mg/Al three-layered composite sheets have been investigated in detail. Uniaxial tensile tests were conducted on composite sheets at 0°, 45°, and 90° to the rolling direction. The results show that the properties of the hot-rolled 5052/AZ31/5052 three-layered composite sheet with fine grain distribution and diffusion layer of 18.71 μm were anisotropic and showed temperature dependence. The 0° direction showed the highest n value and the 90° direction the lowest. The highest Lankford parameter was found in the 45° direction, with the maximum $$ \bar{r} $$ value and minimum absolute value of $$ \Delta r $$ at 230°C. Moreover, hemispherical punch tests revealed that the composite sheet exhibited better formability at 230°C than 170°C, especially in the biaxial stress state. In the equibiaxial tensile stress state, significant anisotropy of the thickness distribution and different fracture appearance were also observed.

The development of membranes with low fuel crossover and high fuel efficiency is a key issue in direct borohydride fuel cells (DBFCs). In previous work, we produced a poly(vinyl alcohol) (PVA)-anion-exchange resin (AER) membrane with a low fuel crossover and a low fuel efficiency by introducing Co ions. In this work, a bilayer membrane was designed to improve the fuel efficiency and cell performance. The bilayer membrane was prepared by casting a PVA-AER wet gel onto the partially desiccated Co-PVA-AER gel. The bilayer membrane showed a borohydride permeability of 1.34 × 10

Asymmetric supercapacitors possess advantages of elevated capacitance, extended output voltage, and then improved power-energy characteristic. Here we report on a composite electrode prepared by electrodepositing manganese oxide into a graphene hydrogel and its capacitive performance in an asymmetric supercapacitor. The manganese oxide/graphene hydrogel exhibits a specific capacitance of 352.9 F g−1 at 1 A g−1. The aqueous asymmetric supercapacitor composed of an active carbon as a negative electrode and the manganese oxide/graphene hydrogel as a positive electrode possesses good cycle stability (91.5% of capacitance retention after 5000 cycles) and is able to deliver an energy density of 41.8 Wh kg−1 at a power density of 0.2 kW kg−1. Its possibility to serve as a power supply for a practical application was verified by lighting up a blue light-emitting diode. These results demonstrate the electrodeposition process has promising prospect in the preparation of high-performance composite electrodes for advanced electrochemical energy storage devices.

Anodic electrodepositing manganese oxide into a graphene hydrogel not only improves the carbon material's capacitive performance, but surface chemical environment of the GO framework is also affected. Apart from the deposition of nano-sized manganese oxide (about 6 nm), Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and cyclic voltammetry results confirm that reduction on oxygen-containing functional groups takes place during the anodic process. After the electrodeposition, weakness of the graphene hydrogel in capacitance is mitigated by the incorporation of the pseudo-capacitive material, with an almost 100% increase. And the composite electrode possesses superior rate capability, reversibility and cycling stability (only 8% deterioration in capacitance after 6000 charge/discharge cycles) as well.

Advanced high-strength steel has great potential for application in automotive and high-speed rail industries owing to its excellent mechanical properties. To predict the forming limit of dual-phase 500 steel sheets (DP500), Banabic’s innovative hydraulic bulging test was conducted on them, and the Gurson–Tvergaard–Needleman (GTN) ductile damage model was used to determine their failure under different strain paths. GTN damage parameters were identified using a hybrid experimental–numerical method based on the equal biaxial hydraulic bulging test. The results show that fracture of all of the DP500 specimens occurred in their polar region in experiments under different strain paths from uniaxial to equal biaxial tension. Moreover, the GTN ductile damage model could not only provide an accurate prediction of the fracture position, but also give an appropriate evaluation of the sheet forming limit under different loading paths.

The planar anisotropy (PA) and tension-compression asymmetry (TCA) of the commercially pure titanium (CP-Ti) were investigated through uniaxial tension and compression experiments at room temperature. By deep drawing experiment, the formability and the earing profile for the CP-Ti were studied at room temperature. The deep drawing simulations using the hardening rules of uniaxial tensile or compression curves were compared with experimental results. The results show that the CP-Ti has obvious PA, and the plastic strain ratiosr0,r45andr90are 1.47, 1.64 and 2.05, respectively. The CP-Ti sheet shows the tension-compression asymmetry of yielding and hardening. The TCA also shows obvious PA. The tension-compression yield strength ratio of 0°, 45° and 90° to the rolling direction are 1.12, 1.08, 1.04, and the tension-compression hardening exponent ratio are 0.86, 0.8 and 0.62, respectively. The simulative results without considering TCA indicate that the forming force, the wall thickness and earing profile are not in good agreement with the experimental ones. Therefore, the earing appeared in 45° is contribution of the PA and TCA. The TCA will reduce the thickness of the deep drawing parts, increase the earing ratio and affect the drawing force.

The preparation and capacitive behaviour of boron-doped birnessite-type manganese dioxide is described. The MnO2 has been deposited directly onto carbon fiber substrate via the in-situ redox reaction between KMnO4 and carbon fiber in the presence of sodium tetraborate. A combination of physical techniques (scan electron microscopy, transmission electron microscope, X-ray diffraction and X-ray photoelectron spectra) and electrochemical methods (cyclic voltammetry, electrochemical impedance spectra and galvanostatic charge/discharge) is used to study the effects of the presence of sodium tetraborate on the deposition process, morphology, microstructure, and capacitive properties. The repulsions among “hunter” ion [B(OH)4]– resulting from the hydrolysis of Na2B4O7 lead the nucleation points to grow outward individually and thus the formation of MnO2 films that are covered with large amounts of isolated nanoparticles about 50–100 nm in diameter. The increasing binding energies of manganese and oxygen should be a result of interstitial boron ions in MnO2 lattice. The electrochemical measurements indicate that the boron-doped MnO2 electrode has larger specific capacitance, better rate capacity as well as superior cycle stability.

The MnO 2 hierarchical hollow microspheres have been prepared by KMnO 4 partial oxidation of MnCO 3 , followed by the complete selective removal of MnCO 3 template with H 2 SO 4 . The as-prepared hollow spheres are about 1–1.5 μm in diameter with a shell about 50 nm in thickness as shown in TEM images, and are mixture of ramsdellite and akhtenskite according to the XRD analysis. The cyclic voltammetry and galvanostatic charge/discharge measurements indicate that the MnO 2 hollow microspheres possess an ideal capacitive characteristic. After experienced a charge/discharge operation for 10,000 cycles, there is only 18.5% decrease in discharge specific capacitance compared with the maximum capacitance (132.1 F g −1 at 50 mV s −1 ). The hierarchical hollow architecture may play a critical role in improving the rate capability and cycling stability of the as-prepared MnO 2 .

Electrodepositing manganese oxide into graphene hydrogel provides a facile and effective way to make full use of structural features of the hydrogel and capacity advantage of manganese oxide. The electrodeposition conditions play a key role in the deposition of manganese oxide, but little is known about their effect on electrochemical properties of the hybrid electrodes. Here, we systematically clarify the influences of deposition parameters (including current density, deposition time, Mn2+ concentration and bath temperature) on the capacitive performance (including apparent capacitance, specific capacitance, rate capability, cycling stability and charge storage mechanism) of manganese oxide/graphene oxide hydrogel hybrid electrodes. Under the proper preparation conditions, the highest specific capacitance of 453.7 F g−1 is obtained, and 92.4% capacitance retention (419.2 F g−1) is maintained after 5000 charge/discharge cycles, indicating excellent charge storage capability and cycling stability.

Synergistic effect of Ce

The compound N-(4,6-dichloropyrimidine-2-yl)benzamide (C11H7Cl2N3O) was synthesized and the corresponding structure was confirmed by 1H NMR, 13C NMR, HRMS, IR, and single-crystal X-ray diffraction. The compound crystallized in a monoclinic system with space group P 21/c, where a = 14.9156(6), b = 16.6291(8), c = 14.4740(6) Å, β = 95.160(2)°, V = 3575.5(3) Å3, Z = 12, Dc = 1.494 g∙cm−3, F(000) = 1632, μ(MoKa) = 3.182 mm−1, final R = 0.0870, and wR = 0.2331 with I > 2σ(I). The crystal structure was found to be stabilized by intermolecular hydrogen bonding interactions N–H···O and C–H···Cl. Furthermore, the results from biological assays indicated that the compound showed a similar protective effect on metolachlor injury in rice seedlings compared to fenclorim at a concentration of 4.0 mg∙L−1. Moreover, the compound exhibited an improved antifungal activity compared to pyrimethanil against S. sclerotiorum and F. oxysporum. Potentially, these results lay the foundation for the development of novel herbicide safeners and fungicides.

Binary logistic regression test for possible factors of SBI. (DOCX 16Â kb)

The boron-doped MnO 2 /carbon fiber composite electrode has been prepared via in situ redox reaction between potassium permanganate and carbon fibers in the presence of boric acid. The addition of boron as dopant results in the increase of growth-rate of MnO 2 crystal and the formation of worm-like nanostructure. Based on the analysis of binding energy, element boron incorporates into the MnO 2 lattice through interstitial mode. The doped electrode with porous framework is beneficial to pseudocapacitive reaction and surface charge storage, leading to higher specific capacitance and superior rate capability. After experienced 1000 cycles, the boron-doped MnO 2 still retain a higher specific capacitance by about 80% of its initial value. The fall in capacitance is blamed to be the combination of the formation of soluble Mn 2+ and the absence of active site on the outer surface.

With increasingly competition in the world shipbuilding market, manual and experiential technique patterns of line heating process could not meet the requirements of modern shipbuilding in product speed and quality. In recent years, the improvement of productivity for line-heating process is one of the goals in the shipbuilding industry, which means an accurate prediction model is very important. In this study, a finite element analysis (FEA) model for the line-heating process was established and experiments were conducted to prove the validity of the model. The final numerical results are in good agreement with experiment results. Based on the FEA model, the feasibility of the multiple-torch process is verified. The multiple-torch process could greatly save processing time, which is entirely feasible in the specific automation implementation. Finally, the effect of heat line spacing is analyzed, which could provide important information for the line-heating process design. The proposed method presents a valuable reference for the study of the similar thermal process.

Self-standing MnO 2 electrodes have been fabricated through the redox reaction between carbon fiber and potassium permanganate. The porous film of birnessite-type MnO 2 deposited tightly onto surfaces of the carbon fibers to form manganese dioxide/carbon fiber cloth electrode. The electrodes have not only excellent capacitive performances, but also superior electrochemical stability. Owing to the formation of thin-film morphology, porous structure and the intimate contact between the electroactive material and the current collector, the MnO 2 film provides an enhancement of the kinetics by short transport/diffusion path lengths, timely accompanying of electrolyte and large specific surface areas, thus both high energy density and high power density are achieved. In addition to the effective release of stress resulting from charge/discharge, the porous structure also facilitates accompanying electrolyte at high rate operation and avoiding dramatic capacitance fade in cycling. The specific capacitance still retains at least about 84% after continuous 5000 charge/discharge cycles.

Electrodepositing manganese oxide in a three-dimensional graphene architecture has barely been explored, and therefore an exploratory but systematic investigation was conducted. A series of manganese oxide/graphene hydrogel electrodes were prepared by galvanostatic technique. The effects of electrodeposition condition, including current density, deposition time, Mn2+concentration and bath temperature, on the morphology and capacitive performance of the deposits were investigated. Nucleation and growth processes of the deposited manganese oxide were then deduced. An optimal capacitance of 452.5 F g−1 was got. This study could provide insight into the crystallization mechanism for electrochemical preparation of MnOx/graphene electrode for advanced energy storage/conversion devices.