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51.
Bei Zhou Yousef Heider Andreas Blaeser Stefan Raith Horst Fischer Bernd Markert 《PAMM》2016,16(1):117-118
The aim of this work is to numerically simulate the gelation of a crosslinking polymer, which is a very complex process involving chemical reactions and phase transitions from a viscous fluid to a viscoelastic solid. A phenomenological model is proposed to simulate the gelation process of agarose droplets, considering the thermal boundary conditions. The numerical model is implemented using the finite element package FlexPDE. The temperature- and time-dependent degree of gelation and the deformation of the droplets during the gelation process are investigated. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
52.
Angela Niedermeyer Bei Zhou Gözde Dursun Marcus Stoffel Aysegül Artmann Bernd Markert 《PAMM》2016,16(1):99-100
Replacement tissues, designed to fill in articular cartilage defects, should exhibit the same properties as the native material. The aim of this study is to foster the understanding of, firstly, the mechanical behavior of the material itself and, secondly, the influence of cultivation parameters on cell seeded implants as well as on cell migration into acellular implants. In this study, acellular cartilage replacement material is theoretically, numerically and experimentally investigated regarding its viscoelastic properties, where a phenomenological model for practical applications is developed. Furthermore, remodeling and cell migration are investigated. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
53.
Bei?Xu RongLan?ZhangEmail author JiFeng?Wang JianShe?ZhaoEmail author 《Journal of Solid State Electrochemistry》2013,17(9):2391-2400
Three novel series of the binuclear metal phthalocyanines M2Pc2, M2Pc2Hc, and M2Nc2 (M?=?Mn(II), Fe(II), Co(II), Ni(II), and Cu(II)) were synthesized and characterized. The electrocatalytic performance of the binuclear compounds to lithium–thionyl chloride battery was evaluated by operating these compounds in the electrolyte of the battery. The results indicated that the binuclear metal phthalocyanines improved the capacity of the battery by an increase of approximately 30–58 %. Of all, Cu2Pc2Hc and Fe2Nc2 displayed the highest increments of 56 and 57 %, respectively. 相似文献
54.
55.
通过高温固相法对醋酸镧(C6H9O6La·xH2O)与高钼酸铵((NH4)6Mo7O24·4H2O)在一定条件下热解制备非Pt催化剂La2Mo2O7(La2O3-2MoO2)。进一步采用2种方法将La2Mo2O7与多壁碳纳米管(MWCNTs)进行复合,一种是将La2Mo2O7喷涂到MWCNTs表层之上得到La2Mo2O7/MWCNTs,另一种是将两者均匀混合掺杂得到La2Mo2O7@MWCNTs,再将上述2种复合材料应用于染料敏化太阳能电池对电极进行相应研究。通过扫描电子显微镜(SEM)表征了复合催化材料的微观形貌,X射线衍射(XRD)确定了微观结构。采用电流密度-光电压曲线、循环伏安,交流阻抗以及塔菲尔极化分析了材料的光电性能。实验结果表明在电解液I3-/I-中,基于La2Mo2O7/MWCNTs与La2Mo2O7@MWCNTs的对电极,相同的条件下在光电池中获得的光电转换效率分别为6.09%和4.84%,明显高于MWCNTs的3.94%和La2Mo2O7的0.87%。电极性能的提高可归因于La2Mo2O7复合催化剂相对大的比表面积和高导电性。 相似文献
56.
Bei‐Bei Zhang Qian Jiang Zhi‐Xin Liao Chao Liu Shi‐Jun Liu 《Helvetica chimica acta》2013,96(7):1281-1289
Phytochemical investigation of the EtOH extract of Euphorbia sieboldiana led to the isolation of four new oleanane‐type triterpenoids, (1β,2α,3β,19β)‐1,2,3,19‐tetrahydroxyolean‐12‐en‐28‐oic acid, (1β,3β,19β)‐1,3,19‐trihydroxyolean‐12‐en‐28‐oic acid, (1β,2α,3β,16β,19β)‐1,2,3,16,19‐pentahydroxyolean‐12‐en‐28‐oic acid, and (1β,2α,3β,19β,23)‐1,2,3,19,23‐pentahydroxyolean‐12‐en‐28‐oic acid, along with 16 known compounds. Their structures were established by extensive 1D‐ and 2D‐NMR, as well as other spectral analyses. Biological evaluation of the four new triterpenoids revealed potent cytotoxic activities against HeLa and Hep‐G2 cells. 相似文献
57.
气相色谱-串联质谱法测定饮用水、酱油和食醋中四种杀鼠剂 总被引:1,自引:0,他引:1
采用气相色谱串联质谱法测定饮用水、酱油和食醋中4种鼠药氟乙酰胺、鼠立死、毒鼠强和杀鼠酮的含量。饮用水样品用固相萃取(苯乙烯二乙烯苯和甲基丙稀酸甲脂聚合物固相萃取柱)富集净化;食醋和酱油样品用乙腈为提取溶剂,加入少量石墨化炭黑去除色素的快速萃取法提取净化,采用INNOWAX弹性的石英毛细管柱分析。结果表明本方法测定选定样品基质的回收率和相对标准偏差分别在57.2%~102.2%,1.9%~9.5%之间;饮用水中除去杀鼠酮的最低检测浓度为2.0μg/L外,其他均小于0.5μg/L;食醋和酱油中杀鼠酮的最低检测浓度为0.10 mg/kg,其他均小于0.025 mg/kg。本方法适用于突发中毒事件中几种食品样品中4种鼠药的同时快速定性和准确定量。 相似文献
58.
A convenient and regioselective one-pot synthesis of 3-chloride or 3-bromide quinoline derivatives was achieved through a Grignard addition reaction by alkynyl Grignard regent to o-trifluoroacetyl aniline and a Cu(II)-catalyzed cyclization–halogenation tandem reaction with aqueous HCl or HBr as electrophilic reagent. 相似文献
59.
“复杂氧化还原电对电极电势的计算”一直是大学化学教学的难点,以此为例开展翻转课堂教学:教师引导学生归纳、类比,厘清难溶盐电极、配合物电极与“金属电极”之间的渊源,完成知识的内化;通过课堂翻转,学生将内化的知识在课堂实践中加以展现与深化,掌握复杂电极在标准状态下电极电势的计算方式。实践表明,该教学模式避免了学生线上学习存在的刷屏、刷题、心理浮躁等现象,有助于推动学生进行深度学习,将碎片化的知识迁移、串联、整合成体系,达到学以致用的目的。 相似文献
60.
Taking advantage of large conjugated structure and reductivity of boron-doped graphenethe palladium nanoparticles/boron-doped graphene catalyst was prepared by electroless deposition method using boron-doped graphene as reductant and stabilizer. The average size of palladium nanoparticles highly dispersed on the surface of boron-doped graphene was about 6.5 nm. The electrochemical sensor was prepared by modifying the as-formed catalyst on the surface of glassy carbon electrode. The obtained electrochemical sensor exhibited an excellent electrochemical catalytic activity for H2 O2 . It exhibited high sensitivity with the detection limit as low as 830 nmol/L and good linearity in the range of 2.5-300 μµmol/L for detection of H2 O2 . It could be utilized for the determination of H2 O2 in milk samples. © 2022, Youke Publishing Co.,Ltd. All rights reserved. 相似文献