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1.
苯、萘、蒽芳烃分子稳定性和分子极化率规律的理论研究   总被引:1,自引:0,他引:1  
苯、萘、蒽芳烃分子稳定性和分子极化率规律的理论研究桑兰芬,杨滢,杜秀华(长春光机学院基础部长春130012)苏忠民,王荣顺(东北师范大学化学系长春130024)关键词苯,分子极化率,同系物本文以苯、萘、蒽等最简单的单、稠环芳烃为例,对其体系稳定性变化...  相似文献   

2.
共轭回路模型与价键结构理论   总被引:4,自引:0,他引:4  
共轭回路模型与价键结构理论班福强戴柏青*(哈尔滨师范大学化学系150000)苯型烃的芳香性理论是离域化学键思想的最初表达。1972年Clar[1]将经典的共轭多环分子的芳香稳定性与芳香六元环的数目有关的化学观点抽象为判定芳香性最强结构的两个标准:1....  相似文献   

3.
党高潮  王丽琴 《分析化学》1995,23(2):137-141
在自制的十六烷基磷酸锡固定相、甲醇-水流动相的色谱体系中,建立了烷基取代苯、不同数目的甲基取代苯、稠环芳烃等溶质的色谱保留值与其分子结构参数(分子连接性指数、范德华体积)之间的回归方程,并用疏溶剂理论予以解释,同时探讨了结构参数与色谱热力学的关系。  相似文献   

4.
用X射线衍射法分析了聚苯乙烯阳离子交换树脂碳化产物石墨化度和微观结构参数,结果表明聚苯乙烯阳离子交换树脂在1000℃以下碳化处理的样品,石墨化程度都很低,属于在中低温条件下较难石墨化处理的树脂样品;H型树脂碳化产物的晶面层有着碳化处理温度升高而依次减小,并且(002)晶面层间距减小速度快于(100)晶面;H型树脂在低温碳化处理条件下,主要是在二维平面结构上演变成石墨微晶,只有碳化处理温度较高时,平面结构的石墨微晶才相互调整,形成纵向平行有序的微晶体;树脂掺杂金属离子后,有利于树脂在碳化过程中形成的石墨微晶层片纵向有序排列;掺杂不同金属离子的树脂碳化样品,在结构参数方面都明显不同于未掺杂的H型树脂碳化样品。  相似文献   

5.
研究了N2H4在间-四(邻-硝基苯基)四苯并卟啉铁(Ⅲ)、钴(Ⅱ)、锌(Ⅱ)和镍(Ⅱ)配合物[MTP(о-NO2)TBP,简称MTBP]修饰石墨电极上的催化电氧化反应,测得该系列金属四苯并卟啉的催化活性的顺序为Co(Ⅱ)TBP>ClFe(Ⅲ)TBP>Ni(Ⅱ)TBP>Zn(Ⅱ)TBP≈石墨,考察了Co(Ⅱ)TBP和ClFe(Ⅲ)TBP催化联氨电氧化反应的动力学过程。结果表明,OH^-和N2H4在C  相似文献   

6.
Wade规则在稠合型硼烷等中的应用   总被引:6,自引:0,他引:6  
本文把Wade规则推广应用于稠合型硼烷和稠合型金属碳硼烷中,导出计算它们价电子数(NVE)的公式。对于稠合型硼烷,本文公式与唐敖庆等的拓扑结构规则的计算结果相同。但本文公式的适用范围比上述两个规则广。  相似文献   

7.
丙烯酰胺与丙烯酸十四酯共聚物的合成及性能研究   总被引:6,自引:0,他引:6  
许国强  黄雪红 《合成化学》1999,7(3):282-287
利用过氧化苯甲酰为引发剂探讨了丙烯酰胺(AM)和丙烯酸十四酯(TA)的自由基共聚合。重点讨论了合成条件如引发剂用量,单体配比、溶剂、温度等对共聚反应及共聚物对苯丙乳胶增稠性能的影响。并用IR和凯达定氮法表征了共聚物的组成,实验结果表明,AMt TA进行沉淀聚合所得到的共物分子量足够大,可以作为疏水缔合型稠剂使用。  相似文献   

8.
GC/MS分析煤抽出物中的含硫多环芳香化合物   总被引:9,自引:3,他引:9  
煤的索氏抽出物中的含硫多环芳香化合物(PASH)由硅胶柱色谱与配体交换薄层色谱(PdCl_2/SiO_2)两步分离,用毛细管气相色谱(FID与FPD)和色质联用仪分析其组成、结构。通过与文献的色谱保留指数相比较、质谱数据验证,鉴定出贵定煤含硫芳香化合物以三、四环结构为主,主要是二苯并噻吩及其C_1~C_3烷基取代物、苯并萘并噻吩及其烷基取代物,其它稠环含硫芳香化合物较少。  相似文献   

9.
毕思玮  李桂芝 《应用化学》1996,13(6):98-100
偶氮型钯(Ⅱ)配合物液晶的合成与表征毕思玮,丁养军李桂芝(曲阜师范大学化学系曲阜273165)(曲阜师范大学生物系阜曲)关键词偶氮型,Pd(Ⅱ).配合物,近晶型,热致型液晶Cope[1]报道了偶氮苯与铂、钯形成的配合物,其后Ghedini[2]合成了...  相似文献   

10.
本将化学修饰石墨探针选择性预分离富集和石墨炉探针原子化学测定的高灵敏度结合起来,建立了用TOPO修饰的石墨探针络合富集Cr(Ⅵ),Nafion修饰的石墨探针交换富集Cr(Ⅲ)的双饰石墨探针顺序分富集,石墨炉探针原子化法测定水体中Cr(Ⅵ)和Cr(Ⅲ)的方法。Cr(Ⅲ)的检出限为1.03ng/mL,线性范围为0-51ng/mL。Cr(Ⅵ)的检出限为0.37ng/mL,线性范围为0-81ng/mL。  相似文献   

11.
本文较系统地研究了正规苯烃和正规晕苯烃的拓扑性质,给出了Cyvin和Gutman于1986年提出的两个猜想的证明。这些拓扑性质的给出和猜想的证明对正规苯烃和正规晕苯烃的判定、产生、分类、计数以及合成和理论研究都有一定的意义。  相似文献   

12.
In this paper, a method to constructively enumerate fusenes and benzenoids with perfect matchings is given. It is based on an algorithm for generating all fusenes and benzenoids and introduces new restrictions into the generation process that avoid the generation of structures without perfect matchings.   相似文献   

13.
The enumeration of benzenoids is studied with the aid of different modifications of a computer program. Known values for the number of cata-condensed and of all benzenoids with h (number of hexagons) up to eight are reproduced. These benzenoids are classified into (a) unbranched of different symmetries and branched cata-condensed, and (b) normal, essentially disconnected and non-Kekuléan peri-condensed. Within the normal benzenoids a more detailed classification is performed: basic benzenoids, fused, or annelated. For h = 9 an almost complete classification along the same lines was achieved.  相似文献   

14.
Flag graphs have been used in the past for describing maps on closed surfaces. In this paper we use them for the first time in mathematical chemistry for describing benzenoids and some other similar structures. Examples include catacondensed and pericondensed benzenoids. Several theorems are included. Symmetries of benzenoid systems, flag graphs, and symmetry type graphs are briefly discussed.  相似文献   

15.
Summary New constant-isomer series are presented. Two classes of constant-isomer series based on the topological correspondence of their member benzenoids are identified. The isomer numbers for the constant-isomer series alternate between singlet and doublet occurrence. Constant-isomer series with the same isomer number possess a pairwise one-to-one topological correspondence between their benzenoid membership. A correspondence also exists between threefold monoradical and diradical benzenoids belonging to these constant-isomer series. These topological relationships represent a new paradigm that we ascribe as an edge effect of our periodic table for benzenoids.  相似文献   

16.
In this paper, we develop a novel adjacency matrix, He-matrix, corresponding to the dualist graph. Without using the graph center concept, we advance a novel nomenclature of polycyclic aromatic hydrocarbons. Further, we derive some distinguishing theorems about PAH molecules and present some results of our automatic derivatization and automatic classification counting of fused PAH molecules.  相似文献   

17.
The newly introduced signature of benzenoids (a sequence of six real numbers Si with i = 6-1) shows the composition of the pi-electron partition by indicating the number of times all rings of the benzenoid are assigned 6, 5, 4, 3, 2, or 1 pi-electrons. It allows the introduction of a new ordering criterion for such polycyclic aromatic hydrocarbons by summing some of the terms in the signature. There is an almost perfect linear correlation between sums S6 + S5 and S4 + S3 for isomeric cata- or peri-fused benzenoids, so that one can sort such isomers according to ascending s 6 + S5 or to descending S4 + S3 sums (the resulting ordering does not differ much and agrees with that based on increasing numbers of Clar sextets and of Kekule structures). Branched cata-condensed benzenoids have higher S6 + S5 sums than isomeric nonbranched systems. For nonisomeric peri-condensed benzenoids, both sums increase with increasing numbers of benzenoid rings and decrease with the number of internal carbon atoms. Other partial sums that have been explored are S6 + S5 + S3 And S6 + S2 + S1, and the last one appears to be more generally applicable as a parameter for the complexity of benzenoids and for ordering isomeric benzenoids.  相似文献   

18.
We recently reported an algorithm to count Kekulé (resonance) structures for convex cyclofusenes using a combinatorial/geometric approach. Previously, we presented an algorithm for counting resonance structures for parallelogram-like benzenoids with holes by counting descending paths using rectangular meshes with holes. In this article, we employ a similar combinatorial/geometric approach to determine algorithms that will facilitate counting of the resonance structures in parallelogram-like benzenoids with no holes.  相似文献   

19.
In order to promote and keep pace with the teaching of new nomenclature of organic compounds, some important revisions about teaching organic nomenclature suggested in Nomenclature of Organic Compounds 2017 were summarized. We proposed some concrete suggestions for using the new principles of the Nomenclature of Organic Compounds 2017 to name the complex organic compounds.  相似文献   

20.
Previously, we presented an algorithm for counting Kekulé structures for parallelogram-like benzenoids with holes by counting descending paths using rectangular meshes with holes. In this article, we describe an algorithm to count Kekulé structures for convex cyclofusenes using a combinatorial/geometric approach.  相似文献   

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