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991.
以N-乙烯基吡咯烷酮为功能单体的S-萘普生印迹聚合物材料的合成及性能研究 总被引:2,自引:0,他引:2
以S-萘普生为模板,N-乙烯基吡咯烷酮为功能单体,二乙烯基苯为交联剂分别按照摩尔比1/4/10、1/4/20和1/4/30合成了分子印迹聚合物(MIP)。采用UV和Chem 3D Pro软件计算模拟研究了功能单体与模板分子之间的相互作用,经半经验量化PM3方法计算得到功能单体与模板分子之间的相互作用能为-20.97 kJ/mol。探讨了交联度对MIP吸附性能和识别能力的影响,结果表明在所研究的O~4mmol/L浓度范围内,MIP对S-萘普生的结合量随着交联度的增加而减小,而交联度为88%的印迹聚合物P3对S-萘普生和阿司匹林的分离因子为2.70,交联度为83%的聚合物P2的分离因子为2.60,交联度为71%的聚合物P1的分离因子为1.44,即高交联度MIP的识别能力优于低交联度的。 相似文献
992.
以氯化十六烷基吡啶为模板剂,在室温下直接合成出介孔TiO2,探讨了合成条件的影响,分别用红外光谱(FT IR)、热分析(TG DTA),X射线粉末衍射(XRD)和N2吸附等温线技术对产物进行了表征.结果表明:样品经均三甲苯和磷酸处理后能有效提高比表面积和热稳定性,具有较高的光催化活性. 相似文献
993.
994.
本文采用阳离子交换树脂为模板,通过离子交换、高温焙烧等过程制备了Fe2O3微球.采用X射线衍射、红外光谱、扫描电镜、X射线能量散射谱仪等分析方法对产物进行了表征.结果表明:所制备的微球直径在300~500 μm之间,微球表面由α-Fe2O3颗粒有序排列组成. 相似文献
995.
介绍了采用光学仪器结合机械模板的方法完成对EAST装置内部部件的安装准直。通过在平面模板上确定基准孔的方法引入内部部件安装的测量基准,最终的第一壁形状则利用特殊形状的检验模板进行校核,使其达到可接受的位置。 相似文献
996.
997.
With the increasing popularity of fingerprint identification technology, its security and privacy have been paid much attention. Only the security and privacy of biological information are insured, the biological technology can be better accepted and used by the public. In this paper, we propose a novel quantum bit(qbit)-based scheme to solve the security and privacy problem existing in the traditional fingerprint identification system. By exploiting the properties of quantum mechanics, our proposed scheme, cancelable remote quantum fingerprint templates protection scheme, can achieve the unconditional security guaranteed in an information-theoretical sense. Moreover, this novel quantum scheme can invalidate most of the attacks aimed at the fingerprint identification system. In addition, the proposed scheme is applicable to the requirement of remote communication with no need to worry about its security and privacy during the transmission. This is an absolute advantage when comparing with other traditional methods. Security analysis shows that the proposed scheme can effectively ensure the communication security and the privacy of users' information for the fingerprint identification. 相似文献
998.
In the past 15 years, the chemistry of reversible covalent bond formation (dynamic covalent chemistry (DCC)) has been exploited to engineer networks of interconverting compounds known as dynamic combinatorial libraries (DCLs). Classically, the distribution of library components is governed by their relative free energies, and so, processes that manipulate the free energy landscape of the DCL can influence the distribution of library members. Within the same time frame, the design and implementation of molecules capable of copying themselves--so-called replicators--has emerged from the field of template-directed synthesis. Harnessing the nonlinear kinetics inherent in replicator behavior offers an attractive strategy for amplification of a target structure within a DCL and, hence, engendering high levels of selectivity within that library. The instructional nature of replicating templates also renders the combination of replication and DCC a potential vehicle for developing complex reaction networks; a prerequisite for the development of the emerging field of systems chemistry. This Concept article explores the role of kinetically and thermodynamically controlled processes within different DCC frameworks. The effects of embedding a replicating system within these DCC frameworks is explored and the consequences of the different topologies of the reaction network for amplification and selectivity within DCLs is highlighted. 相似文献
999.
H_6P_2W_(18)O_(62)/SiO_2:用模板剂制备及光催化降解二甲酚橙的性能 总被引:1,自引:0,他引:1
分别采用非离子表面活性剂(C_3H_6OC_2H_4O)_x(P123),阴离子表面活性剂C_(12)H_(25)NaO_4S(SDS)和C_(18)H_(29)NaO_3S(SDBS)作为模板剂,通过溶胶-凝胶再结合程序升温溶剂热一步法制备了一系列固载杂多酸光催化材料-H_6P_2W_(18)O_(62)/SiO_2。通过傅立叶-红外光谱(FTIR)、X-射线衍射(XRD)、电感耦合等离子体原子发射光谱(ICP-AES)、氮气吸附-脱附测定、透射电子显微镜(TEM)以及扫描电子显微镜配合X-射线能量色散谱仪(SEM-EDS)等测试手段对不同模板剂作用下合成产物进行了对比表征分析。结果表明,不同模板剂作用下的系列固载杂多酸-H_6P_2W_(18)O_(62)/SiO_2产物中母体多酸的Dawson基本结构均未发生明显变化,但固载后比表面积显著不同,其中,经模板剂P123和SDS作用合成的H_6P_2W_(18)O_(62)/SiO_2(P123)和H_6P_2W_(18)O_(62)/SiO_2(SDS)的比表面积高达916和634m~2·g~(-1),且显示为有序介孔材料。以二甲酚橙为模型分子,在微波场作用下,该系列固载多酸光催化性能研究结果显示,它们的光催化活性可被微波显著增强,其中,采用P123作用合成产物的光催化活性最高,60 min内对二甲酚橙的降解率达99%以上。 相似文献
1000.
Efficient synthesis of a chiral [4]pseudocatenane and its derivatives: a novel ship's wheel-like interlocked structure 总被引:2,自引:0,他引:2
A novel chiral[4]pseudocatenane 5H(3)[PF(6)](3) was synthesized efficiently by treatment of a solution of chiral triptycene-based tri(crown ether) 1 and three equivalents of a bis[p-(but-3-enyloxy)benzyl]ammonium salt in CH(2)Cl(2) with a Grubbs II catalyst, followed by hydrogenation. It was found that the ammonium groups in 5H(3)[PF(6)](3) could be deprotonated by 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in acetonitrile or dimethyl sulfoxide (DMSO). Consequently, N-acylation of the ammonium groups was easily performed in the presence of DBU, which resulted in a new class of neutral highly ordered interlocked molecules in good yields. In particular, the incorporation of stopper units, for example, diethyl phosphoramidate, lead to the isolation of the interlocked molecule 10 with an interesting ship's wheel-like structure, which was structurally studied with the help of detailed NMR experiments. Compared with 1, it was further found that the Cotton effect of (R)-1,1'-binaphthyl chromophore at 241 nm was greatly reduced in 5H(3)[PF(6)](3) and its derivatives. Moreover, a new positive Cotton effect at 248 nm appeared in the interlocked molecules; this observation could be attributed to the chirality transfer from the binaphthyl units to the macrocycles lying in the cavities of 1. 相似文献