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Modified BET model and Do and Do (D.D.) model were chosen to interpret the desorption process of water on hard and soft lignites. The organic and inorganic hydrophilic sites were determined by X-ray photoelectron spectroscopy and X-Ray fluorescence spectroscopy. From the modified BET model, only a small part of hydrophilic sites (HSs) acted as effective primary sites due to space restraint, intramolecular hydrogen bond and maybe more than one hydrophilic site connecting with one water molecule. From the D.D. model, the total adsorption sites (St) of Loy Yang lignite (LY) is 18.7 mmol/g, which is higher than that of Shengli (SL) 17.0 mmol/g in spite of lower primary sites, and the saturation concentration of water (qus) in the micropore of LY is 33.7 mmol/g, which is much higher than that of SL (12.5 mmol/g). So the high moisture-holding capacity of LY is mainly determined by the high St and qus, and not the primary sites. The size of water clusters entering the micropores is 7 for SL and 6 for LY, which is related to relative location of HS. When dewatered, the higher total sites density and smaller water cluster size of LY both implied higher dewatering energy. 相似文献
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Min Zhu Yonghong Hu Guirong Li Weijun Ou Panyong Mao Shaojie Xin Yakun Wan 《Nanoscale research letters》2014,9(1):528
Our objective is to develop a rapid and sensitive assay based on magnetic beads to detect the concentration of influenza H3N2. The possibility of using variable domain heavy-chain antibodies (nanobody) as diagnostic tools for influenza H3N2 was investigated. A healthy camel was immunized with inactivated influenza H3N2. A nanobody library of 8 × 108 clones was constructed and phage displayed. After three successive biopanning steps, H3N2-specific nanobodies were successfully isolated, expressed in Escherichia coli, and purified. Sequence analysis of the nanobodies revealed that we possessed four classes of nanobodies against H3N2. Two nanobodies were further used to prepare our rapid diagnostic kit. Biotinylated nanobody was effectively immobilized onto the surface of streptavidin magnetic beads. The modified magnetic beads with nanobody capture specifically influenza H3N2 and can still be recognized by nanobodies conjugated to horseradish peroxidase (HRP) conjugates. Under optimized conditions, the present immunoassay exhibited a relatively high sensitive detection with a limit of 50 ng/mL. In conclusion, by combining magnetic beads with specific nanobodies, this assay provides a promising influenza detection assay to develop a potential rapid, sensitive, and low-cost diagnostic tool to screen for influenza infections. 相似文献
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利用高效液相色谱、红外光谱等分析测试手段,对盐酸苯海拉明中存在的各种杂质进行了全面剖析,并对各杂质含量进行了定量测定,阐述了影响产品水溶液澄明度的原因。这一剖析结果对产品的生产工艺及质量控制均有重要的指导意义。 相似文献
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Shu‐Ping Lee Shyh‐Chyun Yang Yen‐Shih Cheng Wan‐Jung Lien Lean‐Teik Ng 《European Journal of Lipid Science and Technology》2010,112(7):712-719
Tocotrienols, a group of important phytonutrients of palm oil, have been shown to possess antioxidant, anticancer, neuroprotectory, and anti‐inflammatory activities. In this study, our objective was to examine the protective effects of tocotrienol‐rich fraction (TRF) from palm oil on chronic carbon tetrachloride (CCl4)‐induced hepatotoxicity in rats. Animals were subjected to vehicle only (control), CCl4 only, CCl4 + 100 mg/kg silymarin (silymarin), CCl4 + 25 mg/kg TRF (TRF‐25) and CCl4 + 50 mg/kg TRF (TRF‐50) treatments for a period of 8 wks. Results showed that daily oral administration of TRF‐25, TRF‐50, and silymarin prevented the elevation of serum glutamate oxalate transaminase (sGOT) and glutamate pyruvate transaminase (sGPT), liver thiobarbituric acid reactive substances (TBARS), triglycerides and total cholesterol levels, as well as enhancing the liver catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) levels in rats with hepatotoxicity. At 50 mg/kg, the hepatoprotection of TRF was as good as or better than silymarin (100 mg/kg) in normalization of oxidative stress parameters in liver injury rats. These results suggest that TRF exerts effective protection against chronic CCl4‐induced hepatic injury in rats, and its mechanism of action could be related to reducing oxidative stress in the liver tissue. 相似文献
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