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1.
E. V. Chernyshev E. N. Veprov V. A. Petrov S. L. Bogdanov T. Yu. Levina T. I. Petrova V. I. Kashinskii A. A. Zonov A. E. Verkhovskii 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2006,40(1):34-37
Results of a study of tube specimens cut from hot-water boilers show that film-forming octadecyl amine (ODA) used in the process
of preservation removes deposition from the surface of the metal. An ODA film is preserved on the surface after repeated washing
of the latter with hot water. The concentration of chlorides at the surface of the metal after treatment with ODA is lower
than before the treatment.
__________
Translated from élektricheskie Stantsii, No. 11, November 2005, pp. 15–18. 相似文献
2.
以银耳为原料, 采用超声波辅助热水浸提法提取银耳多糖, 以多糖提取率为指标, 以超声波功率、提取料液比、提取温度和提取时间为影响因素, 设计单因素试验, 并通过正交试验得到较佳提取工艺。通过用TRPV1(Transient Receptor Potential Vanilloid1)试剂盒检测了小胶质细胞TRPV1的释放水平, 与脂多糖(Lipopolysaccharide, LPS)对照组相比, 不同质量浓度的银耳多糖组(62.5, 250, 1000 μg/mL)均能不同程度地抑制TRPV1的释放量。说明了银耳多糖对于BV2小胶质细胞炎症具有良好的抑制作用。 相似文献
3.
Field experiments were conducted at Al-Qatif area in the eastern region of Saudi Arabia to study the status and availability of B under B fertilization regime in three types of calcareous soils and to evaluate the response of two alfalfa varieties, Hassawi (local variety) and Hyden (american variety), to increasing levels of added B.Boron was applied at 7 rates as Na2B4O7.10H2O. Four cuttings were taken from each site at different intervals. Data showed that extractable B by hot-water and NH4HCO3-DTPA (8 days after borax application) was significantly (p <0.001) affected by soil type and B applications. The amount of B recovered by hot-water from the three soils, 200 days after borax application, was in the following order: sandy loam > sandy clay loam > clay loam.Total dry matter of alfalfa (4 cuttings) was significantly (p <0.05) affected by soil type, borax application rates and alfalfa variety.The critical level of B in plant as determined by Cate and Nelson analysis, ranged from 148 to 652 mg kg–1 dry matter for Hassawi cultivar and 138 to 521 mg kg–1 for Hyden cultivar in the first harvest. However, the upper critical levels for the 2nd, 3rd and 4th harvests were 800, 875 and 935 mg B kg–1 dry matter for Hassawi and 603, 723 and 812 mg B kg–1 for Hyden varieties, respectively. Nevertheless, the lower critical levels for 2nd, 3rd and 4th harvests ranged from 148 to 153 mg B kg–1 dry matter for Hassawi and 138 to 142 mg B kg–1 for Hyden. 相似文献
4.
5.
In the forest industry, bark is an abundant residue, predominantly converted into calorific energy. As the antioxidant potential of phenolic compounds from sugar maple (Acer saccharum Marsh.) and red maple (Acer rubrum L.) bark has previously been established, the present study focused on the hot-water extraction optimization of these barks. Several process parameters (maple species, temperature, duration, ratio bark/water, particle size) were thus studied and large disparities were found between the two species. Extraction yield, phenolic content, and antioxidant capacity of red maple extracts were several times higher than those of sugar maple extracts. Principal component analysis, applied to the selected best extraction conditions, identified 3–4 clusters depending on the maple species. These groups were sorted from the highest extraction yield and energy consumption combined with the lowest phenolic content and antioxidant capacity, to moderate extraction yield and energy consumption with the highest phenolic content and antioxidant capacity. 相似文献
6.
Effect of enzymatic high temperature prehydrolysis on the subsequent cellulose hydrolysis of steam‐pretreated spruce in high solids concentration
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7.
《流体机械》2016,(12):54-58
构建了一种多功能直膨式太阳能与空气源复合的热泵系统。在常州的冬季及春季分别对试验样机的运行特性进行研究。试验结果表明:系统在冷暖联供的工况下,即同时产生生活热水和冷冻水,整个过程平均COP为6.0;在冬季,太阳辐射强度为354 W/m~2时,系统制生活热水平均COP为4.32;模拟系统供暖,即将循环水从40℃加热至45℃时,测试结果中最低COP为5.07。在春季,太阳辐射强度为856 W/m~2时,系统制生活热水平均COP为5.78。夏季时,系统同时生产冷热水用于生活热水和供冷的需求;冬季时,由于太阳能的辐射,提高了系统的蒸发温度,热泵的性能因此得到提升。 相似文献
8.
电磁水热系统的设计和实现 总被引:1,自引:0,他引:1
阐述了以微机为核心的即热式电磁水热控制系统的工作原理及其关键部分的功能,并给出了主要硬件电路和软件实现。试验证明,该系统升温迅捷,热效率高,温度波动比较小,过电流保护与超温保护等工作性能良好,安全性能好。 相似文献
9.
以桉木溶解浆生产过程中的副产物预水解液为原料,采用水热碳化工艺对预水解液进行处理,以制备碳微球。探讨了水热碳化过程中聚(4-苯乙烯磺酸-马来酸共聚物)钠盐(PSSMA)用量对碳微球形貌及得率的影响,并探究了不同结构碳微球的成形机理。结果表明,预水解液是制备碳微球的理想碳源,PSSMA可通过在碳微球表面提供静电斥力以调控碳微球形貌,使碳微球由交联的球簇结构转变为单分散微球结构和微球超结构。随着PSSMA用量增加和碳化时间的延长,碳微球及其超结构的粒径均呈先下降再趋于平缓的趋势;但PSSMA对碳微球得率的影响较小。 相似文献
10.
芦苇预水解硫酸盐法人纤浆粕的制备及其预水解动力学研究 总被引:1,自引:0,他引:1
对芦苇预水解硫酸盐法试制人纤浆粕的预水解硫酸盐蒸煮最佳工艺条件及其动力学进行了研究。结果表明,芦苇的预水解反应为一级反应。水解过程中,只要控制P-因子相同,即可获得同样品质的半料浆。芦苇在175℃下、保温90min即可溶出约75%的戊聚糖和50%的木素。芦苇预水解的最佳条件为:最高温度175℃,保温时间90min,液比1∶6。芦苇预水解后硫酸盐蒸煮的最佳工艺条件为:用碱量10%(对绝干原料,以Na2O计),硫化度15%,最高温度160℃,保温时间30min,液比1∶4。经CEHA四段漂白后,所制得的人纤浆粕各项指标符合标准要求。 相似文献