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61.
62.
采用多聚磷酸(PPA)/P2O5弱酸体系, 通过傅克反应(Friedel-Crafts reaction)对多壁碳纳米管(MWCNTs)进行功能化改性, 加入己内酰胺后采用原位聚合法制备功能化碳纳米管(F-MWCNTs)/尼龙6(PA6)复合材料, 并熔融纺丝制备复合纤维。通过TEM、TG、DSC、SEM及力学性能测试对复合纤维进行表征。结果表明: 在MWCNTs表面成功地接枝了氨基, F-MWCNTs均匀地分散在PA6基体中, 没有发生团聚现象, 并且与基体具有很好的界面作用; F-MWCNTs的加入, 对复合纤维的熔融温度和结晶度影响不大, 结晶温度有所提高, 并明显提高了复合纤维的热稳定性; 随着F-MWCNTs的加入, 复合纤维的拉伸断裂强度和杨氏模量增加, 当F-MWCNTs质量分数为0.5%时, 拉伸断裂强度和杨氏模量达到最大, 比纯PA6纤维分别提高了45%和208%。 相似文献
63.
采用超声预处理-柠檬酸辅助亚临界水提法从小麦麸皮(以下简称“麦麸”)中提取水溶性膳食纤维。通过单因素实验考察超声预处理功率、柠檬酸/麦麸液固比、亚临界水提取温度和时间对麦麸水溶性膳食纤维得率的影响,在此基础上,采用响应面优化法,对提取工艺参数进行优化。结果表明,最佳提取条件为:超声预处理功率195 W,柠檬酸/麦麸液固比39:1 mL/g,亚临界水提取温度和时间分别为179 ℃和30 min。此时,麦麸水溶性膳食纤维的得率为41.00% ± 0.29%。因此,该方法能够提高麦麸水溶性膳食纤维的得率,且具有提取时间短、绿色、环保等优点,为工业化生产麦麸水溶性膳食纤维提供技术参考。 相似文献
64.
Peichao Lian Xuefeng Zhu Shuzhao Liang Zhong Li Weishen Yang Haihui Wang 《Electrochimica acta》2011,(12):395
A gas–liquid interfacial synthesis approach has been developed to prepare SnO2/graphene nanocomposite. The as-prepared nanocomposite was characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and Brunauer–Emmett–Teller measurements. Field emission scanning electron microscopy and transmission electron microscopy observation revealed the homogeneous distribution of SnO2 nanoparticles (2–6 nm in size) on graphene matrix. The electrochemical performances were evaluated by using coin-type cells versus metallic lithium. The SnO2/graphene nanocomposite prepared by the gas–liquid interface reaction exhibits a high reversible specific capacity of 1304 mAh g−1 at a current density of 100 mA g−1 and excellent rate capability, even at a high current density of 1000 mA g−1, the reversible capacity was still as high as 748 mAh g−1. The electrochemical test results show that the SnO2/graphene nanocomposite prepared by the gas–liquid interfacial synthesis approach is a promising anode material for lithium-ion batteries. 相似文献
65.
Hongfa XiangBingbing Tian Peichao LianZhong Li Haihui Wang 《Journal of Alloys and Compounds》2011,509(26):7205-7209
Li4Ti5O12/graphene composite was prepared by a facile sol-gel method. The lattice structure and morphology of the composite were investigated by X-ray diffraction (XRD) and scanning electronic microscopy (SEM). The electrochemical performances of the electrodes have been investigated compared with the pristine Li4Ti5O12 synthesized by a similar route. The Li4Ti5O12/graphene composite presents a higher capacity and better cycling performance than Li4Ti5O12 at the cutoff of 2.5-1.0 V, especially at high current rate. The excellent electrochemical performance of Li4Ti5O12/graphene electrode could be attributed to the improvement of electronic conductivity from the graphene sheets. When discharged to 0 V, the Li4Ti5O12/graphene composite exhibited a quite high capacity over 274 mAh g−1 below 1.0 V, which was quite beneficial for not only the high energy density but also the safety characteristic of lithium-ion batteries. 相似文献
66.
Dong Zhou Wanlin Wang Haihui Zhang Fanjun Ma Ken Chen Lejun Zhou 《Metallurgical and Materials Transactions B》2014,45(3):1048-1056
The initial shell solidification of liquid steel in the mold has significant influence on both surface and internal quality of the final slab, and it is mainly determined by the high transient high temperature thermodynamics occurring in the mold. This study investigated the effects of casting parameters like casting temperature, mold oscillation frequency, and stroke on the initial solidification of a Sn-Pb alloy through the use of a mold simulator to allow the clear understanding of the inter-relationship between irregular shell solidification, heat transfer, negative strip time (NST), and casting conditions. Results suggested that the shell surface oscillation marks (OMs) are strongly depending upon the fluctuations of meniscus responding temperatures and heat flux. An abrupt sudden fluctuation of high frequency temperature and heat flux at the meniscus during the NST would deteriorate the shell surface and leads to deep OMs. The fluctuations of responding temperature and heat flux are determined by the NST, meniscus solidification, and oil infiltration, which in turn are influenced by casting conditions, like casting temperature, oscillation frequency, stroke, etc. 相似文献
67.
目的:探讨Rho激酶抑制剂Y-27632对脓毒症急性肝损伤的作用。方法:健康成年雄性SD大鼠32只,随机分为假手术组(Sham组)、假手术+Y-27632组(Sham+Y组),盲肠结扎穿孔组(CLP组)和CLP+Y-27632组(CLP+Y组),每组8只。采用CLP方法制备大鼠脓毒症模型,造模24 h心脏采血后安乐死大鼠,收集血清及肝脏组织。苏木精-伊红(HE)染色观察各组大鼠肝组织病理学变化;蛋白质免疫印迹(Western blot)检测各组大鼠肝组织ROCK1和下游NF-κB蛋白的表达情况;免疫组织化学法(ICH)检测大鼠肝脏组织ROCK1蛋白表达;酶联免疫吸附(ELISA)法检测各组大鼠血清肝功能指标ALT、AST水平及肝组织匀浆IL-18、IL-10和谷胱甘肽(GSH)含量变化。结果:与Sham组相比,Sham+Y组肝脏组织病理学无明显变化,CLP组肝细胞排列紊乱,有大量炎症细胞浸润,CLP+Y组炎症细胞浸润较少,肝细胞条索逐渐恢复。与Sham组相比,CLP和CLP+Y组ROCK1蛋白表达增加(P<0.05);与CLP组相比,CLP+Y组ROCK1蛋白表达减少(P<0.05)。与Sham组相比,CLP和CLP+Y组NF-κB蛋白表达增加(P<0.05);与CLP组相比,CLP+Y组NF-κB蛋白表达减少(P<0.05);ICH检测到Sham组肝脏ROCK1少量表达,CLP组和CLP+Y组大量表达;与Sham组相比,CLP和CLP+Y组血清ALT、AST水平升高(P<0.05),与CLP组相比,CLP+Y组ALT、AST水平降低(P<0.05)。与Sham组相比,CLP和CLP+Y组肝组织匀浆IL-18含量升高(P<0.05),CLP组肝组织匀浆IL-10和GSH含量降低(P<0.05),CLP+Y组IL-10和GSH的变化相近(P>0.05);与CLP组相比,CLP+Y组IL-18含量降低(P<0.05),IL-10和GSH含量升高(P<0.05)。 结论:Rho激酶抑制剂可以减轻脓毒症大鼠急性肝损伤,可能与抑制Rho/ROCK/NF-κB信号通路及其下游的炎症因子,减轻肝脏炎症反应,同时降低肝脏氧化应激水平有关。 相似文献
68.
69.
尖晶石锰酸锂电池容量衰减是限制其大规模应用的瓶颈问题,抑制锰溶解是减少其容量衰减的重要措施之一.本文以MnCO_3和Li_2CO_3为原料,采用球磨结合高温固化的方法制备了尖晶石LiMn_2O_4原材料,采用溶胶-凝胶法实现对尖晶石锰酸锂进行表面包覆二氧化钛.将包覆后材料经过高温长时间煅烧,使得金属钛离子能扩散到锰酸锂颗粒材料表层中,形成LiTi_xMn_(2-x)O_4尖晶石结构薄层.通过对锰酸锂在高温电解液中的溶解对比性试验,给出掺杂薄层作用的直接证据,并对全电池高温环境下电化学循环性能进行了对比测试.结果表明,锰酸锂颗粒表面涂覆TiO_2后,经过750℃煅烧6 h,实现了在尖晶石LiMn_2O_4表面形成了LiMn_(2-x)Ti_xO_4掺杂薄层,其形态、结构均与LiMn_2O_4类似.表面掺杂TiO_2工艺能够显著抑制LiMn_2O_4高温环境下的锰离子溶解,提高锰酸锂电池的使用寿命和高温性能. 相似文献
70.
Yanying Wei Yanjie Wang Jun Tang Zhong Li Haihui Wang 《American Institute of Chemical Engineers》2013,59(10):3856-3862
CO2 capture via an oxy‐fuel route through the U‐shaped (Pr0.9La0.1)2(Ni0.74Cu0.21Ga0.05)O4+δ (PLNCG) hollow fiber membrane with 100% CH4 conversion and 100% CO2 selectivity for 450 h has been explored for the first time. X‐ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy characterizations of the spent hollow fiber membrane have also been investigated. All these results indicate that PLNCG hollow fiber membrane shows excellent reaction performance and good stability under oxy‐fuel reaction conditions, which will be a potential rounte for reducing CO2 emissions worldwide. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3856–3862, 2013 相似文献