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61.
Zhixue Sun Kelvin Bongole Jun Yao Yueying Wang James Mboje Kadria Seushi Chuanyin Jiang Tong Wang 《国际能源研究杂志》2020,44(5):3478-3496
The rise in global temperature due to an unceasingly increase in non-condensable gases (NCG) prompts more development of safe and economical CCUS (Carbon Capture Utilization and Storage) technologies. Carbon dioxide (CO2) sequestration with heat mining in deep enhanced geothermal systems (EGSs) is one of the promising methods to reduce CO2 emitted to the atmosphere. In this study, a cyclic alternation of pressures at the injection and production wells is applied in an EGS for heat mining together with CO2 deposit. Simultaneous alternation of the injection and production pressures can significantly increase the amount of CO2 sequestrated compared to applying a fixed pumping or withdrawing pressures at the injector and producer respectively. At the injection well, alternation in pumping pressures at high frequency (small interval of days) increased CO2 sequestration rate. Reducing the pumping frequency resulted in the lowering of the total amount of CO2 sequestrated, lesser than using a fixed pumping pressure. The alternation in pumping frequency has a direct relationship to the CO2 sequestration rate. The frequency of the injection and production pressures refers to the interval in days of the interchange in pressure between high to a low value and vice-versa. Furthermore, simultaneous alternation of pressures at the injection and production wells respectively (double cyclic method) improved geothermal heat extraction efficiency, thus higher performance for both geothermal and CO2 sequestration projects. 相似文献
62.
以蛇纹石酸浸提镁残渣为硅源,碳酸锂为锂源,通过高温固相反应合成了硅酸锂高温固碳材料,探究了煅烧时间、气氛以及物料配比对合成材料高温固碳性能的影响。采用热重-差热综合热分析仪(TG-DTG)研究了蛇纹石酸浸提镁残渣型硅酸锂的CO2吸收性能,并通过扫描电子显微镜(SEM)与X射线衍射仪(XRD)对合成材料的微观形貌与结构特征进行了表征。结果表明:蛇纹石酸浸提镁残渣型硅酸锂具有较好的CO2吸收性能,吸收量可达26.66%;与市售Si O2为硅源相比,蛇纹石酸浸提镁残渣型硅酸锂材料煅烧合成时间缩短,高温固碳性能更优。 相似文献
63.
Targeting the net-zero emission (NZE) by 2050, the hydrogen industry is drastically developing in recent years. However, the technologies of hydrogen upstream production, midstream transportation and storage, and downstream utilization are facing obstacles. In this paper, the development of hydrogen industry from the production, transportation and storage, and sustainable economic development perspectives were reviewed. The current challenges and future outlooks were summarized consequently. In the upstream, blue hydrogen is dominating the current hydrogen supply, and an implementation of carbon capture and sequestration (CCS) can raise its cost by 30%. To achieve an economic feasibility, green hydrogen needs to reduce its cost by 75% to approximately 2 $/kg at the large scale. The research progress in the midterm sector is still in a preliminary stage, where experimental and theoretical investigations need to be conducted in addressing the impact of embrittlement, contamination, and flammability so that they could provide a solid support for material selection and large-scale feasibility studies. In the downstream utilization, blue hydrogen will be used in producing value-added chemicals in the short-term. Over the long-term, green hydrogen will dominate the market owing to its high energy intensity and zero carbon intensity which provides a promising option for energy storage. Technologies in the hydrogen industry require a comprehensive understanding of their economic and environmental benefits over the whole life cycle in supporting operators and policymakers. 相似文献
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66.
Sequestration of cardenolides inOncopeltus fasciatus: Morphological and physiological adaptations 总被引:1,自引:0,他引:1
The morphological and physiological adaptations associated with sequestration of cardenolides by the lygaeidOncopeltus fasciatus are summarized and discussed. Cardenolides are efficiently accumulated inO. fasciatus; however, the insect does not appear to suffer any physiological cost as a result of handling large amounts of these plant toxins. Morphological adaptations of the insect include a modified integument composed of a double layered epidermis with an inner layer (the dorsolateral space) specialized for cardenolide storage. Special weak areas of the cuticle are found on both the thorax and abdomen, which rupture when the insect is squeezed, resulting in the cardenolide-rich contents of the inner epidermal layer being released onto the body surface in the form of discrete spherical droplets. Physiological adaptations include selective sequestration of food plant cardenolides, concentration of cardenolides in the dorsolateral space, passive uptake of cardenolides at the gut and dorsolateral space requiring little energy output, reabsorption of secreted cardenolides by the Malpighian tubules, high in vivo tolerance to cardenolides, and the presence of cardenolide-resistant Na,K-ATPases.Hemiptera-Heteroptera: Lygaeidae. 相似文献
67.
Sequestration of dietary pyrrolizidine alkaloids (PA) by larvae and adults of six European arctiid moth species (Spilosoma lubricipeda, Arctia caja, Phragmatobia fuliginosa, Callimorpha dominula, Diacrisia sannio, andTyria jacobaeae) was investigated for comparison with the well-studied Asian arctiidCreatonotos transiens. Larvae of all species metabolized free PA bases into the respectiveN-oxides. Only adults ofA. caja, P. fuliginosa, andS. lubricipeda, but not their larvae, converted dietary 7(S)-heliotrine to 7(R)-heliotrine, a direct precursor of a male pheromone in some arctiids, 7(R)-hydroxydanaidal. The larval integument figures as the main storage site for resorbed alkaloids; only minor amounts were found in other tissues. In addition, a significant amount of alkaloid is deposited in the cocoon ofArctia caja; only traces of alkaloids could be found in the meconium and the exuviae of this species. A substantial part of the alkaloids fed was degraded to unknown, nonalkaloidal products. 相似文献
68.
Frank R. Stermitz Dale R. Gardner Francois J. Odendaal Paul R. Ehrlich 《Journal of chemical ecology》1986,12(6):1459-1468
Iridoid glycosides were found to be sequestered by natural populations ofEuphydryas anicia after ingestion from the host plantsBesseya alpina, B. plantaginea, andCastilleja integra. Both major iridoids ofB. alpina, cataipol and aucubin, were found in butterfly populations where this was the only host plant. The catalpol-aucubin ratio was higher in the butterflies than in the host plant. AnE. anicia population which uses bothB. plantaginea andC. integra as host plants was found to sequester cataipol as well as another iridoid, macfadienoside. Macfadienoside was the major iridoid ofC. integra, while catalpol esters were the major iridoids ofB. plantaginea. Although it was a major sequestered iridoid, catalpol was a minor constituent in both host plants. The macfadienoside-catalpol ratio in the butterflies from this population was highly variable, and there appeared to be both sex and individual variation in host plant and/or iridoid glucoside utilization byE. anicia. Although other iridoids were present in the host plants, none was sequestered in more than trace amounts.This work was supported by grant CHE-8213714 to FRS, in part by grant DEB-06961 to PRE from the National Science Foundation, and a grant from the Koret Foundation of San Francisco to PRE. Paper 5 in the series Chemistry of the Scrophulariaceae. Paper 4: Roby, M.R. and Stermitz, F.R. 1984.J. Nat. Prod. 47:854–857. 相似文献
69.
Y. Li J. Li S. Ding H. Zhang 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(3):442-449
This article put forward a theoretical system, which is used to analyze co-optimization of CO2 sequestration and enhanced oil recovery by using the methods or theories including the design of experiments, numerical simulation, net present value, and the response surface methods. A CO2 flooding operation in an immiscible water-alternating-gas process of Shanbei extra-low permeability reservoir was estimated preliminarily by using the methods proposed in this article. The result shows that optimized values obtained from predicted values were in good agreement with the values obtained from the simulation model and it is possible to optimize a coupled CO2 sequestration and enhanced oil recovery project. 相似文献
70.
W. Zhang S. Xu P. Lv 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(2):251-256
CO2 geological storage into deep saline aquifers is one of the most promising methods for reducing anthropogenic CO2 emissions into the atmosphere. During the CO2 geological storage, many factors may affect the final success of actual storage projects, including storability, injectivity, and seal security. In order to investigate the impact of the desiccation phenomenon on the physical and chemical behaviors around the injection well, a series of numerical simulations were performed. Simulation results demonstrated that the geochemical reactions play an important role in the CO2 injection stage, especially the dissolution of easily soluble minerals, such as carbonates and sulfate. 相似文献