Vol 7, No 1 (2023)

Table of Contents

Articles

111 Views, 28 PDF Downloads
Shuaipeng Li, Xueni Guo

Abstract

This study investigates the effect of the Si/Zr mass ratio on the morphology, phase composition, and anti-ablation performance of Si-Zr-C composite coatings on C/C composite materials by controlling the Si/Zr mass ratio in the infiltration material. With an increase in the Si/Zr mass ratio in the infiltration material, the coating becomes smoother, and there are changes in the phase composition of the coating. Through ablation testing, it was observed that the anti-ablation performance of the coating initially increases and then decreases with an increase in the Si/Zr mass ratio. The best anti-ablation performance is exhibited when the Si/Zr mass ratio is 6:4, with a mass ablation rate of -3.083×10-5/ g·s-1 after 120s of ablation. The presence of fewer cracks and grain boundaries on the coating surface results in higher coating strength. Additionally, the reaction products ZrO2 and ZrSiO4 enhance the high-temperature stability of SiO2. Moreover, they themselves possess good anti-ablation performance and a lower oxygen diffusion rate, thereby improving the anti-ablation performance of the coating.

PDF
1-9

RESEARCH ARTICLE

20 Views,
Yonghua Dong, Liyun Wang

Abstract

This paper explores the joint use of qualitative and semi-quantitative equipment such as C, H, N element analyzers, x-fluorescence spectrometers, Inductively coupled plasma atomic emission spectrometers (ICP) and gas chromatography-mass spectrometry (gc-ms), the scale sample of cracking gas compressor was analyzed qualitatively and comprehensively. C and H (91.77%) are the main elements in the scale sample of the first stage outlet pipeline of cracking gas compressor, the scaling may be caused by the polymerization of unsaturated hydrocarbons and the coking of macromolecular aromatics. The scale sample of the heat exchanger contains a large amount of inorganic components and the ash content reaches 52.51%, there are also deposits of sodium salts, silicates and sulphates to form scale.

10-14
22 Views,
Youming Dong

Abstract

The structure of food microbial communities has a direct impact on food safety. Genomic methods allow for accurate prediction of pathogens in food. Key steps to achieve this goal include whole-genome sequencing technology, machine learning-optimized data analysis, pan-genomics approaches, traditional molecular biology methods, new bioinformatics tools, and international collaboration and data sharing. Additionally, microbial communities are potentially linked to dietary habits, diseases, obesity, cardiovascular diseases, and the immune system. Monitoring changes in food microbial communities helps in the timely identification of potential food safety issues. The HACCP system and hurdle technology are two important microbial control methods in the field of food safety. Future research directions include the application of omics technologies such as metagenomics, metatranscriptomics, metaproteomics, and metabolomics, as well as the study of nutritional interactions. Although significant progress has been made, challenges remain in data interpretation, industrial application, and the cultivation or identification of difficult-to-culture or unknown microbial species.

15-18
21 Views,
Chunyang Li, Siyu An

Abstract

This paper introduces the development and application of stable isotope internal standard reagents in the field of food safety testing. Firstly, it discusses the application progress of stable isotope technology in food authenticity identification, food safety traceability, and specific compound analysis. Secondly, it explores the use of multiple isotope internal standards in gas chromatography-mass spectrometry (GC-MS) and ultra-high pressure liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) in environmental monitoring, pharmaceutical analysis, and food safety testing. The synthesis methods of stable isotope-labeled compounds and their applications in drug development, biosynthesis research, and food safety testing are analyzed. Finally, the development methods, application fields, challenges, and the importance of domestic development of deuterium-labeled isotope internal standard reagents are discussed. The paper emphasizes the significant role of stable isotope internal standard reagents in improving the accuracy and sensitivity of food safety testing and anticipates their broad application prospects in this field.

19-23
21 Views,
Yongdong Li

Abstract

Heterojunction Technology (HJT) cells, also known as heterojunction cells, feature a unique PN junction structure. They are formed by covering a crystalline silicon substrate with a layer of amorphous silicon film, combining the properties of both amorphous and crystalline silicon. As a type of N-type cell, HJT cells hold significant importance in the photovoltaic field. They offer high conversion efficiency, a straightforward manufacturing process, applicability to thin silicon wafers, a low-temperature coefficient, and no light-induced degradation or potential-induced degradation, and they can generate electricity on both sides. Notably, HJT cells can be advantageously combined with other technologies. By integrating advanced technologies like IBC and perovskite, the theoretical conversion efficiency of HJT cells could potentially exceed 30%. This prospect makes HJT cells a highly competitive choice in the photovoltaic industry.

24-26
22 Views,
Yanyan Qin

Abstract

With the acceleration of industrialization, environmental pollution issues have become increasingly severe. Environmental monitoring, as a crucial means of assessing and controlling environmental quality, is of significant importance for protecting human health and maintaining ecological balance. Inductively Coupled Plasma Mass Spectrometry (ICP-MS), with its high sensitivity, wide dynamic range, and rapid multi-element analysis capabilities, has become an essential tool in the field of environmental monitoring. This paper begins with the principles and development history of ICP-MS, and provides a detailed introduction to its applications in environmental monitoring, particularly in water, soil, and sediment monitoring. Additionally, it elaborates on technological innovations and optimizations in ICP-MS, including the reduction of detection limits, improvement of sensitivity, and advancements in data processing and analysis software. These improvements demonstrate the tremendous potential of ICP-MS technology in enhancing the accuracy and efficiency of environmental monitoring. Through comprehensive and in-depth analysis and discussion, this paper aims to provide scientific and effective technical support for the field of environmental monitoring, thereby promoting the development of monitoring technologies and progress in environmental protection efforts.

27-36


Cookies Notification