Yong Qin^1,2, Xiaoyu Li^1,2, Yanhong Wu^1,2, Hai Wang³, Guiqi Han^1,2,3, Zhuyun Yan^1,2,*

Phyton-International Journal of Experimental Botany, Vol.93, No.1, pp. 119-135, 2024, DOI:10.32604/phyton.2023.046075

Abstract Root exudates serve as crucial mediators for information exchange between plants and soil, and are an important evolutionary mechanism for plants’ adaptation to environmental changes. In this study, 15 different abiotic stress models were established using various stress factors, including drought (D), high temperature (T), nitrogen deficiency (N), phosphorus deficiency (P), and their combinations. We investigated their effects on the seedling growth of Salvia miltiorrhiza Bunge and the activities of Solid-Urease (S-UE), Solid-Nitrite Reductase (S-NiR), Solid-Nitrate Reductase (S-NR), Solid-Phosphotransferase (S-PT), and Solid-Catalase (S-CAT), as well as the contents of polysaccharides in the culture medium. The results showed that the growth… More >

Decheng Li¹, Yan Zhang², Dongdong Ma², Haozhe Geng¹, Yu Wu^1,2,*

Energy Engineering, Vol.120, No.11, pp. 2503-2516, 2023, DOI:10.32604/ee.2023.041803

Abstract The fracturing process of sandstone is inherently complex due to its loose internal structure and deformation adaptability. Liquid nitrogen pre-injection has emerged as a promising approach to damage reservoir rocks, effectively reducing fracture pressure and establishing intricate fracture networks, thus offering a potential solution for reservoir reconstruction. To unravel the fundamental mechanisms governing sandstone fracturing behaviors following liquid nitrogen pre-injection, sandstone fracturing experiments were conducted under varying durations of liquid nitrogen injection, rock temperature, and in-situ stress conditions. The experiments showcased the evolution of injection pressure and fracture characteristics under different testing conditions, complemented by electron microscope analysis to elucidate… More >

Ping Lv¹, Jiufei Liu², Mengran Xu^3,*, Hui Tian^3,4, Huajie Liu³, Yuhuan Bu³, Zhuang Cai³, Junfeng Qu⁵

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2907-2921, 2023, DOI:10.32604/fdmp.2023.029304

Abstract Cementing carbonate reservoirs is generally a difficult task. The so-called thixotropic cement slurry has gained considerable attention in this regard as it can help to fix some notable problems. More precisely, it can easily fill the leakage layer; moreover, its gelling strength can grow rapidly when pumping stops, thereby increasing the resistance to gas channeling, effectively preventing this undesired phenomenon in many cases. High-temperature thixotropic cement slurry systems, however, are still in an early stage of development and additional research is needed to make them a viable option. In the present study, using a self-developed composite high-temperature thixotropic additive as… More >

Haocheng Jiang¹, Jue Zhu^2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.1, pp. 1-2, 2023, DOI:10.32604/icces.2023.09586

Abstract The tests of dynamic mechanical properties of materials at high temperature and high strain rate has always been a difficult issue [1]. In order to perform the dynamic mechanical properties of G550 cold-formed steel at high temperature and high strain rate, a set of Hopkinson Tension test device which can synchronize with high temperature control is developed for material test [2]. The stress-strain curves obtained from the tests were used to explore the influence of temperature and strain rate on the rheological properties of material by combining micro-analysis. The results show that G550 cold-formed steel has obvious strain rate hardening… More >

Zhiyuan Liu¹, Jue Zhu^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.09798

Abstract In order to study the dynamic mechanical properties at high temperature and high strain rate [1] of Q245R steel after corrosion, the electrochemical accelerated corrosion test by constant current method and the high strain rate tensile test at high temperature [2] by High Temperature Synchronous Hopkinson Tensile test device were carried out. The test results show that Q245R steel has obvious strain rate strengthening effect and temperature softening effect, and under certain conditions, temperature becomes the main factor affecting the material properties. In order to consider the heat treatment and corrosion effects, the traditional Johnson-Cook [3-4] constitutive equation was improved,… More >

Xiang Zhang, Hadi Keramati, Martinus Arie, Farah Singer, Ratnesh Tiwari, Amir Shooshtari, Michael Ohadi^*

Frontiers in Heat and Mass Transfer, Vol.11, pp. 1-14, 2018, DOI:10.5098/hmt.11.18

Abstract Heat exchangers are key components of most power conversion systems, a few industrial sectors can particularly benefit from high temperature heat exchangers. Examples include conventional aerospace applications, advanced nuclear power generation systems, and high efficiency stationary and mobile modular fossil fuel to shaft power/electricity conversion systems. This paper provides a review of high temperature heat exchangers in terms of build materials, general design, manufacturing techniques, and operating parameters for the selected applications. Challenges associated with conventional and advanced fabrication technologies of high temperature heat exchangers are discussed. Finally, the paper outlines future research needs of high temperature heat exchangers. More >

Xintong Chen, Pinghua Zhu^*, Xiancui Yan, Lei Yang, Huayu Wang

Journal of Renewable Materials, Vol.11, No.6, pp. 2953-2967, 2023, DOI:10.32604/jrm.2023.027140

Abstract With the emphasis on environmental issues, the recycling of waste concrete, even recycled concrete, has become a hot spot in the field of architecture. But the repeated recycling of waste concrete used in harsh environments is still a complex problem. This paper discusses the durability and recyclability of recycled aggregate concrete (RAC) as a prefabricated material in the harsh environment, the effect of high-temperature curing (60°C, 80°C, and 100°C) on the frost resistance of RAC and physical properties of the second generation recycled coarse aggregate (RCA₂) of RAC after 300 freeze-thaw cycles were studied. The frost resistance of RAC was… More >

Zubing Tang^*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.8, pp. 2161-2170, 2023, DOI:10.32604/fdmp.2023.026608

Abstract The mechanical behavior of the test string in deep wells is generally relatively complex as a result of the high temperature and high pressure, severe dogleg and buckling effects, which in some circumstances can even lead to string failure. Traditional computational methods for the analysis of these behaviors are often inaccurate. For this reason, here a more accurate mechanical model of the test string is introduced by considering variables such as temperature, pressure, wellbore trajectory, and buckling, as well as combining them with the deformation and string constraint conditions brought in by changes in temperature and pressure during the tripping,… More >

Renjun Xie¹, Xingquan Zhang¹, Baolun He^2,*, Ningyu Zheng², Yuqiang Xu^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1385-1395, 2023, DOI:10.32604/fdmp.2023.025454

Abstract The optimization of methods for the quantitative evaluation of risks in drilling engineering is an effective means to ensure safety in situations where high temperature and high pressure blocks are considered. In such a context, this study analyzes the complexity of the drilled wells in such blocks. It is shown that phenomena such as well kick, loss, circulation, and sticking, are related to the imbalance of wellbore pressure. A method for risk quantitative evaluation is proposed accordingly. The method is used to evaluate the risk for 9 drilled wells. By comparing the predictions of the method with actual historical data… More > Graphic Abstract

Yanjun Li¹, Wandong Zhang¹, Jiang Wu¹, Yuhao Yang¹, Chao Zhang¹, Huanqiang Yang^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.5, pp. 1237-1248, 2023, DOI:10.32604/fdmp.2022.023147

Abstract Air channeling in the annulus between the casing and the cement sheath and/or between the cement sheath and formation is the main factor affecting the safe operation of natural gas wells at high temperatures and pressures. Prevention of this problem requires, in general, excellent anti-channeling performances of the cement sheath. Three methods to predict such anti-channeling performances are proposed here, which use the weightless pressure of cement slurry, the permeability of cement stone and the volume expansion rate of cement sheath as input parameters. Guided by this approach, the anti-channeling performances of the cement slurry are evaluated by means of… More >