The stable nanotubular TiO
2 prepared by treating hydrogen titanate nanotubes with sol containing titanium is used as support, and platinum nanoparticles are loaded on the support via photodeposition ...process. The obtained Pt/TiO
2 nanotubes are characterized with transmission electron microscopy, X-ray diffraction, UV–vis absorption spectroscopy and nitrogen adsorption. The photocatalytic performance is evaluated by the photocatalytic degradation rates of methyl orange under UV light irradiation. The results show that the nanotubular structure of support is intact during photodeposition and the Pt/TiO
2 nanotubes exhibit higher photocatalytic activity.
The Agriculture and Forestry discipline in local normal colleges and universities plays an important role in cultivating talents and higher education to serve the local "agriculture, rural areas and ...farmers". The Land Resource Management discipline is a science that studies the use, allocation, and management of land resources and assets, and has comprehensive and practical features. In the context of the proposal of the rural revitalization strategy and the establishment of the Ministry of Natural Resources of the State Council, the importance of cultivating land resource management talents who understands both land planning and urban planning is self-evident, and the teaching reform of Land Resource Management discipline is receiving much attention. Taking the Land Resource Management discipline of Jiangxi Normal University, a key normal university in Jiangxi Province as an example, combining the characteristics of the discipline setting and the development process, we analyzed the existing problems in its development, so as to provide recommendations for the teaching reform of Land Resource Management discipline in local normal colleges and universities.
Research progress based on FBG burst pressure detection Wang, Kexuan; Dong, Xiaoyu; Li, Xinyu ...
2023 3rd International Conference on Frontiers of Electronics, Information and Computation Technologies (ICFEICT)
Conference Proceeding
Due to its advantages in sensitivity, insulation, corrosion resistance and distributed measurement, optical fiber grating pressure sensors have been gradually paid attention to in the fields of ...energy, chemical industry, aerospace and civil engineering. This paper firstly introduces the principle of fiber optic grating sensor, then some research hotspots of fiber grating sensors are reviewed, emphasize on the application and research of FBG sensor in boom pressure measurement, and finally summarizes the difficulties and technical development direction.
With the continuous evolution of network attacks, the risks brought by the network are also increasing. In order to enable network administrators to monitor the network situation more easily, quickly ...and efficiently, and discover security risks such as network anomalies or attacks in a timely manner, this paper proposes a solution about network situation auralization. The novelty of this method lies in that it solves the problems, including high professional requirements, frequent human-computer interaction, and poor situation presentation effect in traditional network security situation visualization, and instead displays the network situation in the form of music. The solution provides two models to be chosen from: one is to use the extracted network traffic data as notes to directly generate music and display it; the other consists of the following procedures: The first step is to calculate and classify the acquired MIDI music collection based on emotional color. The second step requires to slice the extracted network traffic data, performing sampling statistics in different intervals, the network situation of this section is mapped to the corresponding MIDI music collection for music display after analysis.
New types of S
2
O
8
2−
/Al-
x
wt%Ce–Zn–O solid acid catalysts were prepared by the sol–gel method. Their catalytic performances for the synthesis of
n
-butyl acetate from acetic acid and
n
-butanol ...were investigated. The characterization of prepared catalysts was performed using XRD, IR, TG-DSC and SEM. The experimental results showed that the S
2
O
8
2−
/Al-2.5 wt%Ce–Zn–O solid acid catalyst exhibited an optimal esterification performance with 98.71% esterification efficiency under the optimum synthesis conditions. Moreover, the S
2
O
8
2−
/Al-2.5 wt%Ce–Zn–O solid acid catalyst retained its high activity with above 95% esterification efficiency after being used repeatedly for seven times, which indicated that the S
2
O
8
2−
/Al-2.5 wt%Ce–Zn–O solid acid catalyst had excellent stability.
Currently, radio OAM waves have broad applications because they have natural orthogonality. In the present paper, we proposed an optimal design of a concentric circular array with multiple rings for ...generating OAM beams with flat top characteristics. Firstly, we introduced a compact OAM antenna using a sequentially rotated configuration and a cost function of the flat-top pattern. Then, an optimization process is designed and conducted, including three independent simulations of sub-arrays, and rooting of excitation coefficients and rotation angles for individual rings. Simulation results show that the optimized antenna can generate an OAM beam with a ripple coefficient of less than 0.6dB on the torus from -55 to 55 degrees, which meets the requirements of flat-top beams.
The heat supply network bleed valve is located in the steam pipe of the steam turbine heater. When conveying the steam medium of high temperature and high pressure, it impacts the valve disc and pipe ...wall, resulting in flow-induced vibration and noise of the pipe, resulting in excessive pipeline vibration, which is not conducive to the normal operation of the heat supply network and stable steam supply. In this paper, by using large eddy simulation turbulence theory to study bleed valve disc under different rotation angle operating characteristics, pipe flow field regularity of distribution, and the pressure pulsation of measuring points, the Q criterion is applied to analyze the locomotion mechanism of vortex structure in the downstream flow field of the valve disc, the use of common noise prediction method to calculate the noise of the heat supply network structure features, analysis of the inherent law of flow-induced vibration. It is found that with the increase of the rotation angle of the valve disc, there is an obvious negative pressure center area at the back of the valve disc, and the vortex is formed under the action of the adverse pressure gradient. The decrease in vortex size makes the flow efficiency at the back of the valve increase significantly. Large eddy simulation results show that the fluid generates a double vortex structure similar to the dean vortex behind the valve, and is eventually broken and separated due to the dissipation of viscous turbulent kinetic energy. The smaller the rotation angle is, the more seriously the dissipation vortex blocks the flow area near the pipe wall. The noise characteristics of the flow field in the heat supply network present a dipole state and the overall broadband characteristics. The energy of the flow field is concentrated in the low and middle frequency, and there is a peak of noise SPL. Simulation results showed that when the valve disc rotation angle is less than 30°, the vortex structure will seriously block the pipeline flow area, accounting for more than 90%, and the pipeline flow efficiency will decrease significantly with strong pulsation and noise. The fundamental frequency of the noise in the heat supply network shows a frequency doubling relationship with the natural frequency of the structure, and the rotation angle of the valve disc is negative correlation significantly with the magnitude and position of the fundamental frequency of the noise. Both of them can induce the flow-induced vibration and noise of the heat supply network, which complies with the field measurement data.
Vertical distribution of the main bacteria isolated from the Muztagata ice core (about 22.4 m) was investigated by means of cultivation and 16S rRNA sequence analysis. The results showed that the ...amount of culturable bacteria fluctuated with ice core depth, and was more in dirty layer than in clean ice, which suggested the close corresponding relationship between high input of the bacteria deposited by wind and snowflow and dirty layer. Most of the bacteria were psychrophiles and psychrotolerants, including α- and γ-proteobacteria, Cryobacterium psychrophilum, CFB (Cytophaga-Flavobacterium-Bacteroides) group, high-G+C gram-positive bacteria (HGC). Acinetobacter sp. and HGC repeatly occurred in different ice depths, and their quantitative distribution was consistent with the change of the total amount of culturable bacteria with depth, which suggested the main bio-indicator; while Flavobacterium, Cryobacterium psychrophilum, and α-proteobacteria, also functioned as a secondary indicator of climatic and environmental changes. This study is the first report concerning continuous quantitative variation and pattern of the main culturable bacteria in ice core section.
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