Research on Dew Point Corrosion of Materials

2013 ◽  
Vol 281 ◽  
pp. 441-447 ◽  
Author(s):  
Zhi Yuan Liang ◽  
Qin Xin Zhao

To solve the problem of power station boilers' high exhaust temperature and the demand of the dewpoint corrosion prevention and control in the process of flue gas deep cooling, We chose dewpoint corrosion resistant steels BNS, ND and 316L steel as studied objects, which were in situ tested on a boiler of 1000 MW pulverized coal-fired power plant. The results show that 316 L steel is performing superior corrosion resistance. Iron oxides and a small amount of sulphate and chlo-rate are the corrosion products, and the suitable tube metal wall temperature is recommended as 80°C which can avoid the coupling effect between dewpoint corrosion and viscous ash deposition.

2013 ◽  
Vol 54 (1) ◽  
pp. 102-110 ◽  
Author(s):  
Yun-Gang Wang ◽  
Qin-Xin Zhao ◽  
Zhi-Xiang Zhang ◽  
Zhi-Chao Zhang ◽  
Wen-Quan Tao

Facilities ◽  
2017 ◽  
Vol 35 (11/12) ◽  
pp. 590-600 ◽  
Author(s):  
Hamiane Messaoud ◽  
Assafsaf Cherifa

Purpose The purpose of this paper is to study the influence of humidity and temperature on the deterioration of the building stones of the Imedghassen Mausoleum located in Batna, Algeria. Design/methodology/approach Thermo-hygro buttons were used to control the microclimate of the monument (humidity and temperature). Findings The obtained results on the variations in temperature, humidity and also the dew point enabled the confirmation of the relationship between these factors and the origin of the stone deterioration and the degradation state of the monument. Research limitations/implications Scientific research approach in this work is to find a relationship between the factors of degradation and the state of conservation of the monument, using, for the first time, thermos-hygro buttons in situ to follow with great precision the microclimate. Practical implications These results can be extrapolated to all new and old houses having the same environment. Social implications The use of thermo-hygro buttons as an in-situ logger that can monitor and control humidity and temperature (microclimate) is of great importance for the preservation of cultural heritage monuments. Originality/value Thermo-hygro buttons are used for the first time to monitor and control the temperature and humidity on site. Their use makes a great contribution in the field of control degradation of building materials by moisture and temperature.


Author(s):  
Kenneth S. Vecchio ◽  
John A. Hunt

In-situ experiments conducted within a transmission electron microscope provide the operator a unique opportunity to directly observe microstructural phenomena, such as phase transformations and dislocation-precipitate interactions, “as they happen”. However, in-situ experiments usually require a tremendous amount of experimental preparation beforehand, as well as, during the actual experiment. In most cases the researcher must operate and control several pieces of equipment simultaneously. For example, in in-situ deformation experiments, the researcher may have to not only operate the TEM, but also control the straining holder and possibly some recording system such as a video tape machine. When it comes to in-situ fatigue deformation, the experiments became even more complicated with having to control numerous loading cycles while following the slow crack growth. In this paper we will describe a new method for conducting in-situ fatigue experiments using a camputer-controlled tensile straining holder.The tensile straining holder used with computer-control system was manufactured by Philips for the Philips 300 series microscopes. It was necessary to modify the specimen stage area of this holder to work in the Philips 400 series microscopes because the distance between the optic axis and holder airlock is different than in the Philips 300 series microscopes. However, the program and interfacing can easily be modified to work with any goniometer type straining holder which uses a penrmanent magnet motor.


Physchem ◽  
2021 ◽  
Vol 1 (1) ◽  
pp. 26-44
Author(s):  
Chiara Ferrara ◽  
Riccardo Ruffo ◽  
Piercarlo Mustarelli

Extended interphases are playing an increasingly important role in electrochemical energy storage devices and, in particular, in lithium-ion and lithium metal batteries. With this in mind we initially address the differences between the concepts of interface and interphase. After that, we discuss in detail the mechanisms of solid electrolyte interphase (SEI) formation in Li-ion batteries. Then, we analyze the methods for interphase characterization, with emphasis put on in-situ and operando approaches. Finally, we look at the near future by addressing the issues underlying the lithium metal/electrolyte interface, and the emerging role played by the cathode electrolyte interphase when high voltage materials are employed.


RSC Advances ◽  
2018 ◽  
Vol 8 (21) ◽  
pp. 11652-11660 ◽  
Author(s):  
Xiaojun Wang ◽  
Yulong Zhuo ◽  
Kui Zhao ◽  
Wen Zhong

Two coupling processes—solution seepage and chemical replacement—occur in the in situ leaching process of ion-absorbed-rare-earth ore.


2012 ◽  
Vol 616-618 ◽  
pp. 538-542 ◽  
Author(s):  
Fu Xiang Zhang ◽  
Wei Feng Ge ◽  
Xiang Tong Yang ◽  
Wei Zhang ◽  
Jian Xin Peng

To alleviate the problems of casing collapse induced by the coupling effect of rock salt creep and casing wear, the effects of salt creep, attrition rate and casing abrasive position on the equivalent stress on casings in non-uniform in-situ stress field is analyzed by finite-difference model with worn casing, cement and salt formation. It indicates that, creep reduces the yield strength of worn casing to a certain extent; Equivalent stress on casings is bigger and more non-uniform when the abrasion is more serious; Wear position obviously changes the distribution of equivalent stress on casing, and when the wear located along the direction of the minimum in-situ stress, equivalent stress on casing could be the largest that leads to the casing being failed more easily. Equivalent stress on casings increases gradually with creep time increasing and will get to balance in one year or so; In addition, new conclusions are obtained which are different from before: the maximum equivalent stress on casings is in the direction of the minimum horizontal stress, only when the attrition rate of the casing is little; otherwise, it is not. This method could help to improve the wear prediction and design of casings.


2021 ◽  
pp. 1-9
Author(s):  
Sushil Kumar Jaiswal ◽  
Ashok Kumar ◽  
Amit Kumar Rai

Down Syndrome (DS) caused by trisomy 21 results in various congenital and developmental complications in children. It is crucial to cytogenetically diagnose the DS cases early for their proper health management and to reduce the risk of further DS childbirths in mothers. In this study, we performed a cytogenetic analysis of 436 suspected DS cases using karyotyping and fluorescent in situ hybridization. We detected free trisomies (95.3%), robertsonian translocations (2.4%), isochromosomes (0.6%), and mosaics (1.2%). We observed a slightly higher incidence of DS childbirth in younger mothers compared to mothers with advanced age. We compared the somatic aneuploidy in peripheral blood of mothers having DS children (MDS) and control mothers (CM) to identify biomarkers for predicting the risk for DS childbirths. No significant difference was observed. After induced demethylation in peripheral blood cells, we did not observe a significant difference in the frequency of aneuploidy between MDS and CM. In conclusion, free trisomy 21 is the most common type of chromosomal abnormality in DS. A small number of DS cases have translocations and mosaicism of chromosome 21. Additionally, somatic aneuploidy in the peripheral blood from the mother is not an effective marker to predict DS childbirths.


Author(s):  
Lei Fan ◽  
Meiwan Yu ◽  
Aiqing Wu ◽  
Yihu Zhang

Interactions between water and rocks are the main factors affecting the deformation of rock masses on sloped banks by reservoir impoundment. The technology used in laboratory tests of water-rock interaction mechanisms cannot simulate the coupling of water, the rock structure and the initial stress environment. In this work, we develop an in situ hydromechanical true triaxial rock compression tester and apply it to investigate the coupling response of reservoir bank rocks to changing groundwater levels. The tester is composed of a sealed chamber, loader, reactor, and device for measuring deformation, which are all capable of withstanding high water pressures, and a high-precision servo controller. The maximum axial load, lateral load and water pressure are 12 000 kN, 3 000 kN and 3 MPa, respectively. The dimensions of the test specimens are 310 mm×310 mm×620 mm. The test specimens are grey-black basalts with well-developed cracks from the Xiluodu reservoir area. The results show that increasing water pressure promotes axial compression and lateral expansion, while decreasing water pressure causes axial expansion and lateral compression. A water pressure coefficient, K, is introduced as a measure of the hydromechanical coupling effect (expansion or compression) with changing groundwater level. A mechanical tester can be used to perform accurate field tests of the response of wet rocks to hydromechanical coupling. The test results provide new information about the deformation patterns of rock slopes in areas surrounding high dams and reservoirs.Thematic collection: This article is part of the Role of water in destabilizing slopes collection available at: https://www.lyellcollection.org/cc/Role-of-water-in-destabilizing-slopes


2021 ◽  
Author(s):  
José R. Serrano ◽  
Luis Miguel García-Cuevas ◽  
Vishnu Samala ◽  
Juan Antonio López-Carrillo ◽  
Holger Mai

Abstract During the last decade, increasingly advanced turbocharger models have been developed for sizing, engine matching and one-dimensional modeling. This work goes further and, instead of using these models for turbocharged engines design or analysis, it implements them in the data acquisition and control system of a turbocharger gas stand. This way, interesting new capabilities arise. The paper shows that there are important synergies between advanced turbocharger gas stand data acquisition and control systems and the modern turbocharger holistic models that have not been deeply exploited until now. They can be summarized as: on-line heat fluxes analysis, in-situ outlier testing points detection, testing time saving and using digital-twin techniques to monitor turbocharger health during testing.


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