环丁烷

Firstly, quantum chemical method was employed to investigate the mechanism of cationic ring-opening polymerization of tetrahydrofuran and butylene oxide.

本文首先应用量子化学方法分别探讨了四氢呋喃和环氧丁烷的阳离子开环聚合反应机理。

The mechanism of ring-opening cationic polymerization reaction of tetrahydrofuran and butylene oxide was analyzed on the basis of electronic microstructures by using frontier orbitaltheory.

求取了四氢呋喃和环氧丁烷单体与仲氧鎓离子反应的过渡态，并根据频率分析和内禀反应坐标计算对过渡态的合理性进行了确认。

In this disseration, the cationic ring open-polymerization mechanism of THF、 butylene oxide and ethylene oxide were studied on the basis of electronic microstructures by using quantum chemicl method.

本文选取四氢呋喃、环氧丁烷和环氧乙烷的阳离子开环聚合为研究对象，运用量子化学方法从微观层次上对烷氧基化开环聚合过程进行了较为全面的研究。

The studies of the electronic structure of small-saturated hydrocarbon molecules have received much interest, this is because these molecules are prototypes of larger hydrocarbons. In thesis, the structure of the isobutane and cyclopentane were studied by using Hartree-Fock and density function theory with the Gauss basis set, the experimental ionized energy data of the isobutane were analyzed.

有机分子结构的研究是复杂有机系统研究的基础，论文用Hartree-Fock方法和密度泛函理论研究了异丁烷和环戊烷分子的电子结构，并对异丁烷分子的实验电离能谱进行了分析。

The company's main product is high-pressure foam machines, laminating machines, various types of polyurethane products production line, premixed raw materials, storage transportation system, and at the same time undertake cyclopentane, isobutane reconstruction project and polyurethane equipment overhaul , Alteration, repair equipment important spare parts sales.

公司的主要产品为高压发泡机、层压机、各类聚氨酯制品生产线、原料预混、储存输送系统等，并同时承接环戊烷、异丁烷改造工程及聚氨酯设备的大修、改造，设备重要零配件的维修、销售。

Bromacil was synthesized using 2-bromobutane and urea as the starting materials in three steps including condensation,cyclization and bromination with total yield of 61%.

以2-溴丁烷和尿素作为起始原料，经缩合、环化、溴代三步反应得到除草定，总收率为61%。

These compounds are of substantial interest both inviewpoints of theory and practical applications, mainlyunder the stimulus to achieve synthetic models either foractive sites of iron-sulfur proteins or for transitionmetal catalysts. This thesis describes the synthesis, structures andconformations of 51 new iron-sulfur cluster complexes,which have been characterized by elemental analysis andstandard spectroscopic methods. In addition, single-crystalX-ray diffraction analyses were performed for 4 representa-tive new compounds. Reactivities of μ-〓 with mono- and di- Grig-nard reagents derived intermediates toward various organicelectrophilic substrates were studied, along with complexa-tion of arynyl-containing iron-sulfur clusters by 〓Thus, several bridged, non-bridged, monomeric, dimeric,homonuclear, heteronuclear iron-sullfur and iron-sulfur co-balt-carbon cluster complexes were synthesized. A novelreaction and convenient route for the synthesis in highyield of tetranuclear iron complexes 〓 containing atetracoordinated sulfur atom was discovered, whereas aplausible mechanism based on experimental results was propo-sed for the formation of the new cluster type.

鉴于有机铁硫原子簇化学在基础理论发展和应用方面的重要意义，因此我们开展了这一课题的研究，并取得以下主要成果： 1、本文共合成了51个新有机铁硫及含钴碳簇基的有机铁硫原子簇配合物，除用元素分析，NMR，IR，MS法表征其结构和构象外，还用X-光衍射技术测得四个代表性配合物的单晶结构和构象； 2、我们业已发现炔基Grignard试剂同〓可形成一种&开环&与&闭环&中间物的平衡混合物，研究该平衡混合物同各种亲电试剂的反应； 3、研究发现了一种可高产率地形成〓含〓四配位硫挛合簇的新化学反应并对此反应提出了—种有趣的反应机理； 4、首次由1，4-二溴丁烷双Grignard试剂与〓制得一种新型铁硫簇双硫阴离子活性中间体，并进而研究了它的亲核反应性能； 5、找到了通过〓的光化学反应来合成簇合物〓-〓的一条有实用价值的新路线。

The main research now is focused on the polymerization of difluoramino substituted oxetane monomers, the preparation of neopentyl difluoramino nitrato plasticizers, and the molecular design and synthesis of cyclic N2 nitramino geminal difluoramino oxidizers.

目前该领域的研究工作主要集中在二氟氨基取代环氧丁烷聚合物合成，新戊基二氟氨基硝酸酯增塑剂制备，以及环N2硝胺基偕二氟氨基氧化剂的分子设计与合成上。

It have been observed that oxonium ion reacted with water more easily than with THF. So water could be used as ceasing reagent to control the molecular weight of the polymer.

本文还对四氢呋喃、环氧丁烷和环氧乙烷阳离子开环聚合反应中，分子内尾咬、扩环这一典型的副反应进行了理论研究。

By using density functional theory B3LYP/6-311G++method, the geometric configuration was optimized for tetrahydrofuran、butylene oxide、 secondary oxonium ion and tertiary oxonium ion. And parameters about the electronic structure, bondlength, energy of frontier orbital of these species were determined.

采用DFT中的B3LYP/6-311G++方法对四氢呋喃和环氧丁烷单体、仲氧鎓离子以及叔氧鎓离子进行了几何构型的全优化，确定了各个构型的电子结构、键长和前线轨道能量等参数，并运用前线轨道理论从微观层次上分析了四氢呋喃和环氧丁烷的阳离子均聚反应机理。

They weren't aggressive, but I yelled and threw a rock in their direction to get them off the trail and away from me, just in case.

他们没有侵略性，但我大喊，并在他们的方向扔石头让他们过的线索，远离我，以防万一。

In slot 2 in your bag put wrapping paper, quantity does not matter in this case.

在你的书包里槽2把包装纸、数量无关紧要。