PBA—PVC共混膜盐酸普鲁卡因离子选择性电极的研究

以聚丙烯酸丁酯(PBA)及聚氯乙烯(PVC)的共混物为成膜材料，四苯硼-盐酸普鲁卡因离子缔合物为电活性物，制备了盐酸普鲁卡因离子选择性电极．该电极浓度的线性范围为1.0×10     

浅谈建筑工程类院校模糊数学课程的教学方法

本文根据模糊数学课程的教学内容及特点,结合作者的教学实践,针对建筑工程类院校的专业特点,对改进课堂理论教学、引进多媒体教学、增加实践教学等教学方法进行了探索,以激起学生的学习兴趣,促进学生对数学知识的掌握和专业技能的提高,培养学生的实践能力和创新意识。     

Co-S-O三元系优势区相图的计算和绘制 1989-06-29

对Co-S-O三元系,用比较简单的热力学与数学方法进行了计算。程序设计使用TRUE BASIC语言,绘制成该系统的优势区相图。     

基于学分制的人才培养模式创新

人才培养模式的创新是提高人才培养质量的根本。基于河北经贸大学学分制改革,从制度创新、路径选择和培养特色三个方面分析教学管理的创新与实践,选择以自主发展能力、持续发展能力和实践应用能力为核心的应用型人才培养路径。     

食铒种群具有密度制约的一类厌食系统

讨论了食铒种群具有密度制约项的一类厌食系统［２］，给出了其所有可能的拓朴相图，并分析了其正平衡点的Ｈｏｐｆ 分支，此系统的正平衡点可以成为稳定的二阶细焦点，也可以成为不稳定的二阶细焦点，所以第一象限有至少存在三个极限环的可能．     

Low dipole moment large β electrooptic chromophores based on exocyclic double bond conjugated bridge

Novel low dipole moment (μ) and large first hyperpolarizability (β) electrooptic chromophores have been designed based on the special characteristic of reversed dipole moment in the excited state of exocyclic double bond (ECDB) conjugated bridge by the optimization of the substituted method, and their electronic and second-order nonlinear optical properties have been theoretically investigated by employing the AM1/FF and ZINDO/S-CI approaches. By extending the conjugation length and optimizing the donor/acceptor strength, the oscillator strength of the excited transition that contributes to the molecular nonlinearity can be further enhanced. The designed chromophores possess a larger figure of merit (FOM) than that of 4-N,N-dimethylamino-4′-nitrostilbene (DANS), and lower (<5 D) ground state dipole moment.     

十二烷基二羟乙基甲基溴化铵的抗静电性能研究

研究以十二烷基二羟乙基甲基溴化铵(DBMAC)作为PP抗静电剂,当DBMAC添加量为PP的0.5wt%时,制品加工成型7 d后,制品表面电阻率最低可降至2.88×1012Ω.抗静电耐久性良好,且几乎不受洗涤影响.制品对环境湿度依赖性小,环境温度升高,材料表面电阻率逐渐降低.利用X射线衍射和DSC分析了共混材料结晶行为.结果表明:DBMAC的加入没有改变PP晶型,但降低了PP的结晶度.通过TG分析,DBMAC削弱了PP的热稳定性,使PP各特征温度均向低温方向移动.且DBMAC在4种塑料中的抗静电优劣顺序为PP>PE>PS>ABS.     

英、美语发音主要异点

旨在使英语学习者了解美国音与英国音发音的主要异点，以消除在对外交往中可能出现的语言隔阂。     

邓小平改革开放的风险观初探

对邓小平改革开放的风险观产生的时代性、风险观的主要内容、风险观在改革开放中的地位三个方面进行探索性认识.     

Internet QoS: Architectures, Strategies and Mechanisms

As an extensive study of Internet QoS, a framework for emerging Internet QoS strategies is presented. Integrated service (Intserv/R SVP), Differe ntiated service (Diffserv), MPLS, and QoS routing, are overviewed. The key issue s and relationship of these QoS architectures are discussed. Some algorithms in IP QoS implementation and unsolved problems are also studied in this paper. Furt hermore, a new strategies of incorporating Intserv with Diffserv to archive end - to-end QoS is proposed. It is also discussed why MPLS and QoS routing are introduced into this framework, how they differ from and relate to other sch emes and where they fit into the Diffserv architecture. The timesc ales of different QoS strategies are also studied and some proposals for Qo S routing deployment are given.