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91.
Monitoring the temperature in liquid hydrogen (LH2) storage tanks on ships is important for the safety of maritime navigation. In addition, accurate temperature measurement is also required for commercial transactions. Temperature and pressure define the density of liquid hydrogen, which is directly linked to trading interests. In this study, we developed and tested a liquid hydrogen temperature monitoring system that uses platinum resistance sensors with a nominal electrical resistance of approximately 1000 Ω at room temperature, PT-1000, for marine applications. The temperature measurements were carried out using a newly developed temperature monitoring system under different pressure conditions. The measured values are compared with a calibrated reference PT-1000 resistance thermometer. We confirm a measurement accuracy of ±50 mK in a pressure range of 0.1 MPa–0.5 MPa.  相似文献   
92.
Chiwu Bu  Liu  Tao  Li  Rui  Zhao  Bo  Tang  Qingju 《Russian Journal of Nondestructive Testing》2021,57(11):1018-1026
Russian Journal of Nondestructive Testing - Infrared images of aerospace materials were collected by infrared camera and analyzed to evaluate debonding defects. However, it is difficult to identify...  相似文献   
93.
Atomically dispersed transition metals anchored on N-doped carbon have been successfully developed as promising electrocatalysts for acidic oxygen reduction reaction (ORR). Nonetheless, how to introduce and construct single-atomic active sites is still a big challenge. Herein, a novel concave dodecahedron catalyst of N-doped carbon (FeCuNC) with well confined atomically dispersed bivalent Fe sites was facilely developed via a Cu-assisted induced strategy. The obtained catalyst delivered outstanding ORR performance in 0.5 M H2SO4 media with a half-wave potential (E1/2) of 0.82 V (vs reversible hydrogen electrode, RHE), stemming from the highly active bivalent Fe-Nx sites with sufficient exposure and accessibility guaranteed by the high specific surface area and curved surface. This work provides a simple but efficient metal-assisted induced strategy to tune the configurations of atomically dispersed active sites as well as microscopy structures of carbon matrix to develop promising PGM-free catalysts for proton exchange membrane fuel cell (PEMFC) applications.  相似文献   
94.
To understand the hydrogen (H) behavior in the carbide precipitates, the dissolution and diffusion properties of interstitial H in the transition metal carbide (TMC; TM = Hf, Nb, Ta, Ti, V, and Zr) were studied by first-principles calculations. In these carbides, it can be seen that H tends to occupy the trigonal site (tri2-site) surrounded by three transition metal atoms and one carbon atom rather than the face center (fc-site) and the body center (bc-site) which with the larger space. We found that the bonding interaction between H atom and the nearest-neighbor (1NN) carbon atom is the dominant influence on the stability of H dissolution. Besides, we obtained the temperature-dependent solubility and diffusion coefficients of H in TMC and pure vanadium through Sievert's law and transition state theory. Compared with pure vanadium, H shows the worse solubility in TMC, and it is more difficult for hydrogen to migrate in TMC, but segregate toward the interface. Furthermore, it is interesting to note that, the diffusion barrier and the H solution energy show a linear relationship for transition metal carbides in the same period. These results can help us deepen the understanding of H behavior in vanadium alloys strengthened by carbide precipitates, and furtherly providing the theoretical guidance for the design of alloys with excellent performance.  相似文献   
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The article substantiates that the transformation of the world economy associated with Industry 4.0 leads to a significant change in the way resources are used and affects the possibility of implementing the concept of sustainable development. In this regard, a combined analysis of the concept of new industrial development and the concept of sustainable development, as well as an assessment of the current practice of their implementation is required. In this paper, such an analysis was carried out on the example of water resources management. The paper proposes a methodology for assessing the correlation of water management and industrial development levels of regions. This includes the use of both traditional statistical approaches to the analysis of the level of development of economic systems, and elements of data mining. The neural network is constructed in order to estimate the forecasted values of the water intensity of the gross regional product when the indicators of the level of industrial development of the regions change. The results show that the most significant indicators for changing water intensity include advanced production technologies used, the share of value-added to high-tech industries, and innovative activities of organisations.

  相似文献   
98.
针对实验室管理中存在的安全问题,提出并设计了一种基于云平台的智能实验室远程监控系统.利用FRID技术对进出人员信息进行记录.在实验室内安装温度传感器和湿度传感器,把实验室内的环境数据上传至云平台,当温度传感器和湿度传感器检测到实验室环境参数异常时,云平台将实验室的数据信息及时反馈到当时正在值班的管理员的移动电话端上,提示实验室可能存安全隐患.烟雾传感器可以检测实验室的烟雾浓度和可燃气体.实验表明,系统可以在不同环境下正常工作,且运行可靠,反馈给云平台的数据和检测到的实验室环境参数准确,有助于提高实验室安全性.  相似文献   
99.
Aflatoxins represent a global public health and economic concern as they are responsible for significant adverse health and economic issues affecting consumers and farmers worldwide. Produced by fungal species from the Aspergillus genus, aflatoxins are a toxic, mutagenic, and carcinogenic group of fungal metabolites that routinely contaminate food and agricultural products. Climate and diet are essential factors in the aflatoxin contamination of food and subsequent human exposure process. Countri es with warmer climates and staple foods that are aflatoxin-susceptible shoulder a substantial portion of the global aflatoxins burden. Enactment of regulations, prevention of pre- and postharvest contamination, decontamination, and detoxification have been used to prevent human dietary exposure to aflatoxin. Exploiting their chemical and structural properties, means are devised to detect and quantify aflatoxin presence in foods. Herein, recent developments in several important aspects impacting aflatoxin contamination of the food supply, including: fungal producers of the toxin, occurrence in food, worldwide regulations, detection methods, preventive strategies, and removal and degradation methods were reviewed and presented. In conclusion, aflatoxin continues to be a major food safety problem, especially in developing countries where regulatory limits do not exist or are not adequately enforced. Finally, knowledge gaps and current challenges in each discussed aspect were identified, and new solutions were proposed.  相似文献   
100.
The present paper provides insights into the feasibility of using hydrogen and bioethanol blends as energy carriers in the foreseeable future upon discussions on the advantages and the disadvantages. The comprehensive overviews on the production, storage, and transportation of hydrogen and bioethanol have been made; and the current problems and potential solutions for the three stages have been summarized. Finally, the prospections on hydrogen and bioethanol could be expect optimistically.  相似文献   
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