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排序方式: 共有8311条查询结果,搜索用时 15 毫秒
1.
《Ceramics International》2022,48(16):22699-22711
An integrated experimental and thermodynamic modeling study of the phase equilibria in the ‘CuO0.5’-MgO-SiO2 system in equilibrium with liquid Cu metal has been undertaken to better understand the reactions between MgO-based refractories and liquid slag in copper converting and refining processes. New experimental phase equilibria data at 1250–1680 °C were obtained for this system using a high-temperature equilibration of synthetic mixtures with predetermined compositions in silica ampoules or magnesia crucibles, a rapid quenching technique, and electron probe X-ray microanalysis of the equilibrated phase compositions. The system has been shown to contain primary phase fields of cristobalite (SiO2), tridymite (SiO2), pyroxene/protoenstatite (MgSiO3), olivine/forsterite (Mg2SiO4), periclase (MgO), and cuprite (Cu2O). Three regions of 2-liquid immiscibility were found—two in the high-silica range of compositions above the cristobalite primary phase field (close to ‘CuO0.5’-SiO2 and MgO–SiO2 binaries) and one in the low-SiO2, high-‘CuO0.5’ compositional region above the periclase and olivine phase fields. The results obtained in this study indicate that silica in high-copper refining slags likely led to olivine and pyroxene phase formation, increased solubility of MgO in liquid slag, and decline in the performance of MgO-based refractories. New experimental data were used in the development of a thermodynamic database describing this pseudo-ternary system.  相似文献   
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栾龙威 《纺织报告》2020,(1):122-123,126
保护非物质文化遗产的难点主要在于"非遗"很难接地气,导致传承不能很好地进行。白裤瑶服饰是国家级非物质文化遗产,如何更好地保护和发展白裤瑶服饰文化成为众多学者关注的问题。文章以IP为视角,对白裤瑶服饰文化展开保护路径的研究,提出白裤瑶服饰文化IP的发展路径要从深入发掘白裤瑶服饰文化内核,运用现代科技辅助IP建构,打造有情感、年轻化的白裤瑶文化IP,产学研用结合发展,跨界合作等方面进行,旨在为保护白裤瑶服饰文化尽绵薄之力。  相似文献   
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WIDESTAR II系统为了更好的满足用户需求,在WIDESTAR系统的基础之上对移动终端、基站设备以及核心网节点进行了再次开发,从而实现了更高的传输速率以及与IMS或其他通用IP技术的灵活兼容。本文中,将首先对WIDESTAR II系统进行简要的介绍与分析,然后,对此系统所采用频谱效率提高方法、IP兼容技术以及时延降低策略等卫星移动通信机制进行研究与验证。  相似文献   
4.
Gelatin (90.6 ± 0.1%) was optimally prepared by response surface methodology from yellowfin tuna (Thunnus albacares, YT) abdominal skin. To investigate bioactive properties of enzymatic hydrolysates from the abdominal skin gelatin (ASG), ASG was hydrolysed with alcalase, protamex, neutrase and flavourzyme as affected by hydrolysis time. Antioxidant, nitrite scavenging and angiotensin‐I converting enzyme (ACE) inhibitory activities of the hydrolysates were determined. Antioxidant activities of the hydrolysates were found through linoleic acid peroxidation inhibitory effects. Alcalase‐derived hydrolysates (AHs) were more effective than others in metal ions chelating, superoxide anion scavenging and hydroxyl radical scavenging activities (P < 0.05). AHs showed significantly stronger nitrite scavenging activities (44.4–60.7%) than others (P < 0.05). Fraction A from AH showed strong ACE inhibitory activity (IC50 of 0.75 mg mL?1). These results suggest that YT ASG and its enzymatic hydrolysates could be functional food and/or pharmaceutical ingredients with potent antioxidant, anticarcinogenic and antihypertensive benefits.  相似文献   
5.
Tuna cooking juice is a by‐product from the tuna canning industry. In this study, tuna cooking juice was hydrolysed by proteases extracted from the spleen. Tuna cooking juice showed the highest ACE inhibitory and Ca‐binding activities after hydrolysis for 270 and 180 min, respectively. The hydrolysate was further fractionated by ultrafiltration. The permeate exhibited highest ACE inhibitory and Ca‐binding activities when passed through 1 and 5 kDa cut‐off membranes, respectively. Gel filtration chromatography was used to determine the MW of bioactive peptides that exhibited highest ACE inhibitory and Ca‐binding activities. Those peptides that exhibited highest ACE inhibitory and Ca‐binding activities were the MW range of 238–829 Da and 1355–1880 Da, respectively. These results suggest that the tuna cooking juice and the spleen protease extract are a potential source of bioactive peptides that can be utilised as bioactive ingredients in functional food and nutraceuticals.  相似文献   
6.
I have utilized Patent Examination Data System (PEDS) to propose a patent filing strategy decomposed by sub-divisions within a Research and Development (R&D) department of a large organization. The unique method relies on breaking the patent cost into fixed cost and variable cost. The variable cost is determined by automatically retrieving data from PEDS. The data includes historical average of number of interactions of a patent applicant with the patent office, grouped by technology domains. The variable cost may then be used in a linear programming model to obtain optimal filing targets for each sub-division within the R&D department. The proposed strategy will help an organization to take objective decisions for determining patent filing targets for its sub-divisions, which will eventually help with an efficient patent strategy for the organization.  相似文献   
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“双闪”铜冶炼工艺技术具有环境指标优越、综合能耗低、自动化程度高等优势,在中国得到广泛应用,目前中国已建成4个“双闪”铜冶炼厂,1个正在建设。通过对肯尼科特犹他冶炼厂、阳谷祥光铜业有限公司、铜陵有色金冠铜业分公司、广西金川有色金属有限公司、中铜东南铜业有限公司以及阳新弘盛铜业有限公司“双闪”铜冶炼工艺技术进行对比,研究了铜精矿干燥、铜精矿输送、闪速熔炼、冰铜粒化、冰铜制粉和输送、闪速吹炼、阳极精炼、残极处理以及烟气处理等工艺技术的发展情况,为“双闪”铜冶炼工艺技术的应用,以及未来的发展方向提供思路。  相似文献   
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