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991.
Huali Hu Wenbiao Shen Pengxia Li 《International Journal of Food Science & Technology》2014,49(2):399-409
Here we investigated the effect of hydrogen sulphide (H2S) on postharvest quality of mulberry fruit and possible underlying mechanisms. Endogenous H2S content first increased after harvest and then decreased sharply with the process of ripening and senescence. A fumigation with H2S released from 0.8 mm NaHS solution could significantly enhance the endogenous H2S content by increasing the activities of D‐cysteine desulfhydrase and L‐cysteine desulfhydrase. NaHS could significantly slow down the ripening rate of mulberry fruit and reduce the respiratory intensity and anthocyanin content. Moreover, H2S fumigation was able to obviously delay or slow down the decreases in soluble protein, titratable acidity and ascorbate contents. Further results showed that activities of representative antioxidant enzymes in H2S‐treated sample were higher than those of control samples during storage, resulting in a decrease in superoxide anion production. Together, these results clearly indicate that H2S fumigation has a potential role in the preservation of mulberries. 相似文献
992.
先阐述了服务器虚拟化技术的特点和优势,分析了华三的虚拟化产品特点,再论述了服务器虚拟化技术如何应用于校园数字化建设,以期达到降低运行成本、提升使用效率的目的。 相似文献
993.
分析了盐酸脱吸工序中稀盐酸储槽抽裂事故产生的原因;通过稀盐酸储槽的压力式液位计DCS历史曲线记录来间接分析稀盐酸储槽内压力变化情况,剖析负压的形成过程。结果表明:脱吸塔产生较大的负压是因为系统急停、温度下降后在略低于盐酸溶液恒沸点时发生冷凝相变而引起的。 相似文献
994.
995.
《Fusion Engineering and Design》2014,89(9-10):2001-2007
This paper summarises the present status of the ITER tritiated waste management strategy under development in France. This paper describes the specific challenges posed by this radioactive waste containing tritium as well as the solutions planned for the various waste categories and the implementation expected for the ITER tritiated waste, including the features of the future interim storage facility called INTERMED. Several options to reduce temporary storage duration as well as to minimise out-gassing rates and tritium discharges into the environment are under study, the related issues and the preliminary results obtained are shown. The first lessons learned for fusion development and their extrapolation to future reactors are outlined based on four parameters: materials, operating temperature, fuel cycle efficiency and tritium removal technologies. 相似文献
996.
Latent heat energy storage characteristics of building composites of bentonite clay and pumice sand with different organic PCMs
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In the present work, six new kinds of building composite PCMs (BCPCMs), PS/octadecane, BC/octadecane, PS/CA–MA, BC/CA–MA, PS/PEG1000, and BC/PEG1000 composites, were prepared by using vacuum impregnation method. The maximum percent of PCM in the composites was assigned to be 12, 13, 18, 23, 30, and 42 wt%, respectively. The form‐stable BCPCMs were characterized using SEM, FT‐IR, DSC, and TG analysis techniques. The characterization results showed the existence of homogenous dispersion of the PCM into the PBM matrixes. The DSC measurements indicated that the melting temperatures of the form‐stable BCPCMs are in the range of 20–33°C while they have latent heats of melting in the range of about 28–55 J/g. These results make them promising BCPCMs for low temperature‐passive TES applications in buildings. Thermal cycling test indicated that the prepared BCPCMs have good thermal reliability and chemical stability. TG analysis proved that the prepared BCPCMs have good thermal durability. In addition, the thermal conductivity of BCPCMs was enhanced considerably by addition of expanded graphite (EG). The improvement in thermal conductivity of the BCPCMs caused appreciably reduction in their melting times. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
997.
998.
《International Journal of Hydrogen Energy》2022,47(63):27071-27079
Clean hydrogen is a promising option for reducing carbon dioxide emissions, but it has not yet been used as an energy carrier at the scale required for meeting the net-zero target by 2050. Hydrogen molecules are smaller than nitrogen and methane molecules. Hydrogen, nitrogen, and methane have densities of 0.09 g/L, 1.25 g/L, and 0.71 g/L, respectively, at the standard temperature and pressure. Our knowledge of the geological formations is based on responses to the larger and heavier gases; it is unclear whether we can apply this knowledge to store hydrogen at the required scale.We investigate the single-phase flow of hydrogen in the subsurface and compare it with the single-phase flows of nitrogen and methane. The comparison with nitrogen is helpful because it is used under laboratory conditions. The comparison with methane is also beneficial because engineers understand its behavior under in-situ conditions. We use the Knudsen number (Kn) to determine the flow behaviors under laminar conditions within two domains. The first is a permeable medium representing a conventional gas reservoir, and the second is caprock. Our study shows that the existing knowledge of the first domain's permeability applies to hydrogen flow; however, it is unrealistic for the second domain. The single-phase permeability of the caprock obtained by nitrogen in the laboratory underestimates hydrogen permeability at low pressures (<10 MPa), and the deviation is a non-linear function of pressure. Our study also shows that hydrogen permeability is always larger than methane permeability in the caprock. The difference between the two, controlled by the reservoir pressure, reached 70% in the caprock. The presented results have applications if hydrogen storage in gas reservoirs becomes a reality. 相似文献
999.
Xiucai Wang Weiqiang Cai Ze Xiao Guangguang Yang Xinmei Yu Jianwen Chen Dongchu Chen Qingfeng Zhang Min Chen 《Journal of the European Ceramic Society》2021,41(10):5163-5169
AgNbO3 lead free AFE ceramics are considered as one of the promising alternatives to energy storage applications. In the majority of studies concerning the preparation of AgNbO3 AFE ceramics, an oxygen atmosphere is required to achieve high performance, increasing the complexity of the fabrication process. Herein, a facile approach to preparing AgNbO3 ceramics in the ambient air was reported, in which the AgNbO3 ultrafine powder with stable perovskite structure was synthesized by hydrothermal method instead of the conventional ball milling process, leading to a lower temperature of phase formation and thus smaller grain size. The resulting ceramics sintered at 940 °C displayed high breakdown strength (216 kV/cm) and a recoverable energy density of 3.26 J/cm3 with efficiency of 53.5 %. Also, the high thermal stability of recoverable energy density (with minimal variation of ≤20 %) and efficiency (≤ 10 %) over 30–150℃, enables AgNbO3 ceramics achieved to be a promising candidate for energy storage applications. 相似文献
1000.
《International Journal of Hydrogen Energy》2020,45(30):15281-15293
In this work, absorption/desorption isotherms of the LaNi3·6Mn0·3Al0·4Co0.7 alloy, have been determined from the experimental data at three temperatures (TFluid = 298 K, TFluid = 303 K, and TFluid = 313 K). However, the experimental isotherms are compared with a proposed theoretical model. The physicochemical parameters of the proposed model are determined from the experimental data. Using these parameters, the absorption and desorption processes of hydrogen by the LaNi3·6Mn0·3Al0·4Co0.7 alloy can be compared. During the absorption/desorption process, the behaviors of each parameter are studied under the effect of temperature and pressure. In addition, internal energy, entropy, and enthalpy are calculated by using the proposed model. On the other hand, the temperature and pressure effects on the variation of these functions have been studied. The calculated physicochemical parameters suggested that the hydrogen absorption/desorption process in the LaNi3·6Mn0·3Al0·4Co0.7 alloy was feasible, spontaneous and exothermic in nature. 相似文献