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排序方式: 共有167条查询结果,搜索用时 15 毫秒
101.
生物质裂解残炭制备活性炭 总被引:1,自引:0,他引:1
用生物质裂解残炭制备活性炭,采用了水蒸气活化的方法,应用正交实验法对诸多影响因子进行考察,在筛选关键因子并优化工艺条件(活化温度770-780℃、活化时间4h)后,可以得到碘值691.94mg/g,亚甲蓝值280.93mg/g左右的活性炭产品。 相似文献
102.
用裂解气相色谱-质谱法分析丁香油中的成分 总被引:5,自引:0,他引:5
目的研究对丁香油成分进行分离、鉴定的方法。方法采用裂解 毛细管气相色谱 质谱联用技术对丁香油成分进行分离并定性、定量。结果丁香挥发油中主要成分是丁香油酚和 β 石竹烯 ,相对含量约为 89%。 结论确定了用裂解 毛细管气相色谱 质谱联用技术进行天然植物鉴定及评价的方法。 相似文献
103.
基于纳米材料角度研究石榴皮炭止泻作用物质基础 总被引:1,自引:1,他引:0
目的在石榴皮炭Granati Pericarpium Carbonisatum中发现并分离出新型纳米类成分,并通过动物实验来研究其止泻作用。方法利用高温热解法对生石榴皮进行炭化,并对炭化产物进行萃取、滤过分离和透析得到一种具有水溶性的新型纳米类成分,命名为石榴皮炭纳米类成分(GPC-NCs)。采用透射电子显微镜、高分辨透射电子显微镜、傅里叶变换红外光谱、紫外光谱、荧光光谱、高效液相色谱、X射线光电子能谱和X射线衍射对GPC-NCs进行表征。使用小鼠腹泻模型观察小鼠腹泻指数、腹泻潜伏期和肠道传输功能,以此来评价和证实GPC-NCs的止泻作用。结果从石榴皮炭中分离出来的GPC-NCs外形为类球形,粒径均匀分布在1.2~2.3 nm,晶格间距为0.321 nm,荧光量子产率为0.45%。GPC-NCs能够减少小鼠腹泻指数和腹泻潜伏期时间,并对番泻叶水煎剂所致的小肠运动功能亢进具有拮抗作用。结论 GPC-NCs的显著止泻效果,不仅为石榴皮炭的物质基础研究提供了一个新思路,也为GPC-NCs在止泻领域的潜在生物医学和医疗保健应用提供了新的见解。 相似文献
104.
Gang Zhou Chuanqiang Li Haobo Wang Wei Zeng Tianqing Ling Lin Jiang Rukai Li Qizheng Liu Ying Cheng Dan Zhou 《Materials》2022,15(12)
The production of high-performance, low-cost warm mix additives (WMa) for matrix asphalt remains a challenge. The pyrolysis method was employed to prepare wax-based WMa using waste polypropylene plastic (WPP) as the raw material in this study. Penetration, softening point, ductility, rotational viscosity, and dynamic shear rheological tests were performed to determine the physical and rheological properties of the modified asphalt. The adhesion properties were characterized using the surface free energy (SFE) method. We proved that the pyrolysis temperature and pressure play a synergistic role in the production of wax-based WMa from WPPs. The product prepared at 380 °C and 1.0 MPa (380-1.0) can improve the penetration of matrix asphalt by 61% and reduce the viscosity (135 °C) of matrix asphalt by 48.6%. Furthermore, the modified asphalt shows favorable elasticity, rutting resistance, and adhesion properties; thus, it serves as a promising WMa for asphalt binders. 相似文献
105.
To examine the pyrolysis and combustion characteristics of epoxy asphalt, the heat and smoke release characteristics were analyzed via TG-MS and cone calorimeter tests, and the surface morphology of residual carbon after pyrolysis and combustion was observed via scanning electron microscopy. The results showed that the smoke produce rate of epoxy asphalt was high in the early stage, and then sharply decreased. Moreover, the total smoke produced was close to that of base asphalt, and the surface of residual carbon presented an irregular network structure, which was rough and loose, and had few holes, however most of them existed in the form of embedded nonpenetration. The heat and smoke release characteristics of epoxy asphalt showed that it is not a simple fusion of base asphalt and epoxy resin. Instead, they promote, interact with, and affect each other, and the influence of epoxy resin was greater than that of base asphalt. 相似文献
106.
The chemical content, mechanical capability, and dimensional stability of bamboo fibers (BFs) are all directly related to the hygroscopic behavior, which is crucial for industrial applications. To support the utilization of BFs, the structural and chemical composition of BFs with different opening times after mechanical rolling were investigated in this study, and the Guggenheim–Anderson–de Boer (GAB) model was selected to predict their moisture-adsorption properties. The results showed that the length and diameter of the fibers gradually decreased with the increase in the number of openings, and the fibers gradually separated from bundles into single fibers. It was also observed that the treated BFs exhibited different equilibrium moisture contents (EMCs). BFs with a smaller number of openings had a higher hemicellulose content and more exposed parenchyma cells on the fibers, which increased the number of water adsorption sites. As the number of openings increased, the parenchyma cells on the fibers decreased, and the lignin content increased, which reduced the number of fiber moisture-adsorption sites and decreased the EMC of the fibers. 相似文献
107.
108.
丙酮缩二乙醇液相裂解制备2—乙氧基丙烯 总被引:3,自引:0,他引:3
丙酮和原甲酸三乙酯以氯化铵为催化剂反应制得丙酮缩二乙醇,再在硅油中高温裂解制得2-乙氧基丙烯,总收率64.8%。 相似文献
109.
用裂解气相色谱分析了流行性出血热病毒J10株,乙型脑炎病毒A2株及SA14株感染的小白鼠乳鼠脑,肺组织及正常小白鼠乳鼠脑,肺组织。从裂解色谱图中观察到若干特征峰,同时还有多个峰面积比例的改变。据此,有可能借助于裂解气相色谱法快速检测鉴别组织中感染的病毒。 相似文献
110.
用电加热金属丝网快速热解装置,在氮气气氛和常压条件下,考察神府煤和东胜镜质组和丝质组富集物的热解行为及快速热解焦的燃烧气化特性。随热解终温和加热速率的升高,失重率增加,燃烧特性温度向高温方向移动。 相似文献