光电化学传感材料的制备及应用进展

光电化学传感材料是光电化学传感器的核心功能材料,其结构性质决定了光电化学传感器的分析性能和应用范围。本文介绍了常用光电化学传感材料的制备方法及应用领域,综述了近年来该领域的研究进展并对光电化学传感材料未来的发展方向进行了展望。     

3-辛基噻吩的质谱分析

共轭聚合物通常具有一些独特的物理性质,如高的电导率、电致发光、电致变色、非线性光学性质等。这类共轭聚合物包括聚苯胺、聚噻吩、聚吡咯、聚对苯乙炔、聚对苯等。自英国剑桥大学的Burrougs等人[1]采用聚对苯乙炔成功地制备了第一个聚合物电致发光器件以来,对聚合物电致发光     

乙烯基溴化镁与苯基取代氯甲烷反应的CIDNP效应

化学诱导动态核极化(CIDNP)巳广泛地用于研究溶液中的各种自由基反应。CIDNP研究表明,在Grignard试剂的生成以及Grignard试剂与卤代烃的反应中,很多是按自由基历程进行的。我们曾报道,乙烯基溴化镁(1)与三苯基氯甲烷(2)反应时,生成三苯基甲烷(4)和乙炔(5),并检测到反应溶液中三苯甲基自由基的ESR谱;1与二苯基氯甲烷(6)反应生成1,1,2,2-四苯基乙烷(7),二苯基甲烷(8),3,3-二苯基丙烯(9),1,3-丁二烯(10)和溴乙烯(11),并提出这些反应可能是通过自由基中间体进行的。为了进一步探讨反应机理,我们对题目化合物的反应进行了CIDNP实验,取得了一些很有意义的结果。     

稀土元素在6063合金中的分布及其作用机理

用金相观察、扫描电镜的波谱和能谱分析结果表明,稀土在6063铝合金铸态组织中富集于晶界,稀土促进了Si和Fe向晶界偏聚,减少了针状铁相,铸态组织均匀、细化,强度提高。过量稀土会形成Al—La类稀土夹杂物,分布在晶界和晶内,使铸态组织粗化,合金强度下降。含稀土的铝合金型材中铁相有所细化,稀土化合物呈球团状,强度及硬度有所提高。     

THE MECHANISM FOR THE FORMATION OF Z- AND E-β-STYRYLMAGNESIUM BROMIDE AND THEIR REACTIONS WITH TRITYL CHLORIDE

The Grignard reagents with the retention of configuration and partial isomerizationare formed in the reactions of Z- and E-β-bromostyrene with magnesium in THF. Sty-tene, phenylacetylene and E,E-diphenylbutadiene-1,3 are produced as byproducts. Whenthe reaction of Z-β-bromostyrene with magnesium was carried out in THF-d_8, CIDNPeffects were observed for the products of Z-β-styrylmagnesium bromide, E-β-styrene-dand E, E-diphenylbutadiene-1,3. According to the CIDNP and the products obtainedfrom the reactions of these two Grignard reagents with carbon dioxide, it is proposedthat a free radical mechanism, initiated by one electron transfer from magnesium to β-bromostyrene, is involved in the formation of β-styrylmagnesium bromide. The investi-gation on the reactions of the title Grignard reagents with trityl chloride showed thatvinylic Grignard reagent radical cation formed in ET reaction can undergo β-hydrogenmigration. The different distribution of AA, AB and BB types of products obtainedfrom the     

基于数模混合的混沌映射实现

混沌随机序列发生器在数字实现时面临有限字长效应, 无法严格保证伪随机序列的非周期性. 构建了一类包含最少模拟器件的新数模混合系统, 分析比较了此类系统的非线性动力学行为. 利用现场可编程逻辑门阵列和RC电路实现了混沌映射, 构造了稳定的高速随机序列发生器, 可产生100 Gbit/s以上速率的随机数. 研究表明, 数模混合系统的混沌性对元件参数变化不敏感, 数模实现验证了新系统的存在性和物理上的可实现性. 系统易于集成在数字加密、保密通信和雷达波形产生等应用系统中.     

一类两菌株传染病模型的稳定性分析

建立和讨论一类具有比例接种疫苗丧失率的两菌株SIJVS传染病模型,给出了该模型基本再生数和侵入再生数的表达式,分析了无病平衡点、菌株占优平衡点、共存平衡点的存在性和稳定性.     

三元体系La（NO_3）_3－Gly－H_2O的研究

测定了三元体系Ｌａ（ＮＯ＿３）＿３－Ｇｌｙ－Ｈ＿２Ｏ在２５℃时的溶度和饱和溶液的折光指数：报道了三元体系中生成的三元配合物：Ｌａ（ＮＯ＿３）＿３－Ｇｌｙ－Ｈ＿２Ｏｂ和Ｌａ（Ｇｌｙ）４（Ｏ３）３，Ｈ２Ｏ用熔点、红外光谱及热分析测定了名配合物的一些物理化学性质。     

《高等代数》“线上教学”随笔

本文回顾了疫情期间《高等代数》课程“线上教学”的教学过程,具体剖析了“教师指导下的学生自主学习与教师线上直播课相结合的教学方法”的环节和要素,总结了提高各环节的效率和实现各环节、各要素间完美对接的经验,并提出了适用于常态性教学的“线下课堂教学与线上教学相结合”的教学改革探索新方向.     

Multistage Random Growing Small-World Networks with Power-Law Degree Distribution

We present a simple rule which could generate scale-free networks with very large clustering coefficient and very small average distance. These networks, called the multistage random growing networks （MRGNs）, are constructed by a two-stage adding process for each new node. The analytic results of the power-law exponent = 3 and the clustering coefficient C = 0.81 are obtained, which agree with the simulation results approximately. In addition, we find that the average distance of the networks increases logarithmically with the network size, which is consistent with the theoretical predictions. Since many real-world networks are both scale-free and small-world, the MRGNs may perform well in mimicking reality.