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1.
提出了“有机同秩列”、“有机同秩物”、“有机同秩异构体”等概念体系,并以单取代烷烃同秩物Xi-(CH2)/-H(Xi=F、CI、Br、I、NO2、CN、NC、OH、NH2、SH、COOH、CHO)为例,对其气相标准摩尔生成焓(△rHm)、电离能(IP)的结构-性能关系进行了研究,分别对j=2~8的七组同秩物的生成焓及j=2~4的三组同秩物的电离能建立了数学模型:△rHm(j)=a+b△iHm(1)+cPEI(R)和IP(j):a+bIP(1)+bPEI(R),得到了有意义的结果.研究表明,从有机同秩物的角度可以建立一种新的分子结构.性能相关方法,它与有机同系物方法相互独立又互为补充.本文提出的概念体系不仅增加了新的有机化学理论和概念,还为有机物结构-性能变化规律的研究开辟了新视角.  相似文献   

2.
通过2-甲基-4-对甲苯基-1-苯甲酰基-2,3-二氢-1H-1,5-苯并二氮杂与由不对称1-苯基-2-偶氮-1,3-丁二酮热解产生的a-羰基烯酮的[2+4]环加成反应制备了标题化合物(C34H30N2O3,Mr=514.62),用X射线衍射测定了其单晶结构。晶体属单斜晶系,空间群为P21/n,a=11.560(1),b=19.058(3),c=13.207(2)A,β=106.82(1)°,V=2785.2(7)A3,Z=4,Dc=1.230g.cm-3,MoKa(λ=0.71073A),μ=0.064mm-1,F(000)=1088,2278个可观测衍子射点,R=0.046,Rw=0.049。分子骨架为由苯环、具有类扭船式构象的七元二氮杂环和略微扭曲的唑酮环构成的三环体系。  相似文献   

3.
以CO(NO3)2,2,2'-联吡啶(2,2'-bipy)及NaVO3为原料,采用水热法于200℃合成了一种新的有机.无机杂化材料——Co(2,2'-bipy)(H2O)V2O6(1),其结构经IR,热重分析及X-射线单晶衍射表征。结果表明,1属于单钭晶系,空间群为P21/c,晶胞参数为:a=7.8556(3)A,b=21.0562(5)A,c=9.5521(6)A,a=90.000^o,β=110.236(5)^o,y=90.000^o,V=1423.65(8)A^3,Z=2,Dc=2.126g·cm^-3,μ(MoKα)=2.548mm^-1,R1=0.0586,wR2:0.0935。1为一种二维层状结构,由[VO4]四面体通过共顶点构成的一维钒氧链,链与链之间以[Co(2,2'-bipy)(H2O)]^2+基团连接而成。  相似文献   

4.
标题两个化合物是在反应体系(NH4)3VS4/CuX/PPh3/NEt4X(X=Br,Ⅰ)中采用低温固相反应方法得到的,单晶X射线结构分析表明:VS4(CuPPh3)5Br2(Ⅰ)和VS4-(CuPPh3)5I2(Ⅱ)是同构的,其中晶体(Ⅰ)属于单斜晶系,空间群P211/c,Mr=19682,a=20.215(7),b=15.691(4),c=27.345(9)A,β=95.29(3)°,V=8637.0A3,Z=4,Dc=1.51g/cm3,F(000)=3968,μ(MoKa)=24.6cm-1,R=0.078。晶体(Ⅱ)亦属于单斜晶系,Mr=2062.2,空间群P21/c,a=20.1613(2),b=15.9718(2),c=27.7427(3)A,β=96.07(1)°,V=8883.4A3,Z=4,Dc=1.54g/cm3,F(000)=4112,μ(MoKa)=22.0cm-1,R=0.068。簇合物(Ⅰ)和(Ⅱ)的簇芯结构可描述为共面的2个开口的扭曲立方烷,在这两个簇合物中,V原子仍保持反应起始物[VS4]3-中的四面体配位,5个CU原子呈近似的四方锥排列,V原子基本上处于Cu5四方锥底面的中心。其中1个Cu原子为平面三角形配位,另外4个Cu原子为严重畸变的四面体配位。  相似文献   

5.
A new clip molecule 1 based on diethoxycarbonyl glycoluril, C46H34ChN4O8, has been synthesized and characterized by single-crystal X-ray diffraction. The crystal belongs to triclinic, space group P1 with a = 11.3674(8), b = 11.3674(8), c = 16.9704(12) A, a = 70.0690(10), β= 72.2310(10), y = 78.0880(10)°, V= 1993.2(2) A3, Z = 2, Dc = 1.521 g/cm3, μ(MoKa) = 0.361 mml, F(000) = 940, the final R = 0.0422 and wR = 0.1144 for 22997 observed reflections with 1 〉 2o(I). The crystal structural analysis shows that C-H……O and C-H……Cl hydrogen bonds, C-H-……π, C-CI……π supramolecular interactions, andπ-π packing interaction stabilized the whole crystal structure. The binding study by fluorescence spectroscope titration showed that the title molecule can selectively recognize Fe3+ with fluorescence quenching.  相似文献   

6.
标题化合物C23H26O4是由水杨醛与5,5-二甲基-1,3-环己二酮在N,N-二甲基甲酰胺中反应而得.结构通过单晶X-射线行射法确定,其晶体属于单料晶系,空间群P21/c,a=7.056(7),b=20.263(3),c=13.665(2)A,β=93.32(1)°,V=1950.7(4)A3,Mr=366.46,Dc=1.248g/cm3,Z=4,μ(MoKa)=0.84cm-1,F(000)=784。晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最后的偏离因子R=0.068,Rw=0.075。晶体结构分析结果表明,分子中存在一个共轭的烯醇式结构。  相似文献   

7.
以尿素与氯化胆碱为原料制备的低共熔点离子液体为反应介质,在离子热体系下制备了[NH4]2·[In(OH)(PO4)(H2O)]2,单晶结构分析表明晶体空间群为P41212,a=b=9.4309(4)A,c=11.1173(10)A,α=β=γ=90°,Z=4,V=988.79(11)A^3,R1=0.0767,wR2=0.2027。晶体结构中In与P分别采用八面体与四面体配位。八面体与四面体通过顶角O原子连接,形成4,6-net网状结构。晶体在300℃下几乎没有失重。  相似文献   

8.
A novel energetic combustion catalyst, 4-amino-3,S-dinitropyrazole copper salt ([Cu(adnp)2(H2O)2]), was synthesized in a yield of 93.6% for the first time. The single crystal of [Cu(adnp)2(H2O)2] was determined by single crystal X-ray diffraction. It crystallizes in a triclinic system, space group p^-1 with crystal parameters a = 5.541(3) A, b = 7.926(4) A, c = 10.231(5) A,β = 101.372(8)°, V = 398.3(3) A3, Z = 1, μ = 1.467 mm^-1, F(0 0 0) = 243, and Dc = 2.000 g cm^-3. The thermal behavior and non-isothermal decomposition reaction kinetics of [Cu(adnp)2(H2O)2] were studied by means of different heating rate differential scanning calorimetry (DSC). The kinetic equation of major exothermic decomposition reaction for [Cu(adnp)2(H2O)2] was obtained. The entropy of activation (△S≠), enthalpy of activation (△H≠), free energy of activation (△G≠), the self-accelerating decomposition temperature (TSADT) and the critical temperature of thermal explosion (Tb) are 59.42 j mol^-1 K^-1, 169.5 kJ mol^-1, 1141.26 kJ mol ^-1 457.3 K and 468.1 K, respectively.  相似文献   

9.
利用雪松二醇苯基硼酸酯进行不对称合成反应,制得标题化合物并测定结构.其晶体属正交晶系,空间群为P212121。结晶学多数为:a=5.728(3),b=8.543(3),c=41.267(7)A,V=2019.7A3;Z=4,Dc=1.23g/cm3,μ(CuKa)=17.7cm-1,R=0.0072,Rw=20.0077.独立可观察反射点数(I>3σ(I))为739个。由晶体结构图可看出,由于雪松二醇基团的空间住阻效应,反应产物有很高的非对称选择性。  相似文献   

10.
合成并测定了2,11,14-三氯-5,8-二氧-3,4,9,10-双(4,4’-三氟甲苯并)-13,15-(2’,6’)吡啶环十五-1,12-二烯酮的单晶结构。晶体分子式C23H15F6N3O4,Mr=511.38,晶体属单斜晶系,空间群P21/c,晶胞参数a=6.732(2),b=15.751(4),c=20.420(8)A,β=96.54(3)°,V=2151.6A3,Z=4,Dc=1.579g/cm3,μ(MOKO)=1.360cm-1,F(000)=1040。分子含有A、B、C、D四个环,D、C苯环对称连有2个三氟甲基,中间A环为含氧、氮的十五员王冠大杂环,整个分子为近平面结构。  相似文献   

11.
低维数下的高分子(如在二维薄膜或一维管道及孔洞中)的各种行为由于更加触及高分子的动力学、热力学本质而逐渐成为高分子科学研究的热点之一.实验表明,薄膜中聚合物的玻璃化转变温度、结晶动力学及形貌等与本体有很大的偏离.我们先前的研究结果表明,在基板的作用下,共混物薄膜的相形态会发生逆转;  相似文献   

12.
We investigate the surface-directed phase separation of spin-coated polystyrene/poly(methyl methacrylate) (PS/PMMA) blends on prepatterned octadecyltrichlorosilane (OTS)-glass substrates under various experimental conditions. As a result of tandem processes of spinodal decomposition and selective wetting of polymer components during spin-coating, low-energy OTS stripes and high-energy glass surfaces laterally arrange the phase-separated polymers according to the chemical pattern on the substrate. Optimal pattern replication was achieved when the length scale of phase separation, controlled via the polymer concentration of the spin-coating solution, matched the smallest feature dimension in a striped chemical pattern possessing two alternating distances between stripes. It was also shown that polymer blend patterns were most closely registered with the underlying substrate when the PS/PMMA composition ratio (30/70, w/w) matched the areal fraction of OTS on the glass surface (~30%). The influence of solvents demonstrated that a solvent with a relatively low volatility, such toluene, was required for patterning so that domain feature sizes were able to coarsen to the size of the patterned features before film vitrification. As well, we showed that the technique and optimized conditions developed in this study could be applied to pattern photoluminescent CdS quantum dots into microscale arrays of parallel lines via spin-coating onto transparent OTS-glass substrates.  相似文献   

13.
用小角激光光散射(SALLS)、相差显微镜(PCM)、示差扫描量热仪(DSC)和偏光显微镜(POM)研究了聚丙烯/二元乙丙橡胶(iPP/EPR)共混体系的相分离行为和等温结晶行为.发现iPP/EPR(50/50,W/W)发生的液-液相分离遵循spinodal机理.通过Cahn-Hilliard方程求得了不同实验温度下iPP/EPR的表观扩散系数(Dapp)以及spinodal温度(Ts).考察了不同相分离程度的iPP/EPR体系结晶动力学,发现延长相分离时间(tps)或提高相分离温度(Tps)均会导致半结晶时间(t1/2)增大,即结晶速率降低.这被归于EPR成核作用的降低.动力学分析结果表明Avrami模型适用于描述该体系的等温结晶过程,其结晶机理基本不受相分离程度的影响,结晶均以瞬时成核和三维生长为主.  相似文献   

14.
It was tried to form Pickering emulsion by use of paraffin wax as a phase change material (PCM) and SiC as solid powder and to apply to the preparation of the hybrid microcapsules with the interfacial polycondensation reaction. Pickering emulsion could be formed by stirring PCM and SiC in the continuous water phase. The mean diameter of PCM droplets in the (O/W) emulsion decreased with the added amount of SiC. The SiC weight adhered on the surface of PCM droplets become the maximum in the continuous phase with pH 6.8. The hybrid microcapsules with the shell made of SiC and polyurea resin film could be prepared by using Pickering emulsion. There was a critical adhesion weight of SiC, above which the hybrid microcapsules could not be formed. Thermal conductivity of hybrid microcapsules could be improved as compared with the PCM microcapsules. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

15.
The objective of this study was to investigate the significance of inner and outer phase pressure, as well as interfacial film strength on W/O/W multiple emulsion stability using microscopy and long-term stability tests. It was observed that immediately upon applying a coverslip to samples the multiple droplets deformed and there was coalescence of the inner aqueous droplets. Under certain conditions (such as lipophilic surfactant concentration and internal phase osmotic pressure) the destabilized multiple emulsions formed unique metastable structures that had a "dimpled" appearance. The formation of these metastable structures correlated with the real-time instability of the W/O/W multiple emulsions investigated. Multiple emulsion stability also correlated with the interfacial film strength (measured by interfacial elasticity) of the hydrophobic surfactant at the mineral oil/external continuous aqueous phase interface. The formation of the metastable dimpled structures and the long-term stability of the multiple emulsions were dependent on the osmotic pressure of the inner droplets and the Laplace curvature pressure as described by the Walstra Equation (P. Walstra, "Encyclopedia of Emulsion Technology" (P. Becher, Ed.), Vol. 4. Dekker, New York, 1996). It appears that the effect of coverslip pressure on multiple emulsions may be useful as an accelerated stability testing method or for initial formulation screening.  相似文献   

16.
We use Dip-Pen Nanolithography (DPN) to generate monolayer surface templates for guiding pattern formation in spin-coated polymer blend films. We study template-directed pattern formation in blends of polystyrene/poly(2-vinylpyridine) (PS/P2VP) as well as blends of PS and the semiconducting conjugated polymer poly(3-hexylthiophene) (P3HT). We show that acid-terminated monolayers can be used to template pattern formation in PS/P3HT blends, while hydrophobic monolayers can be used to template pattern formation in PS/P2VP blends. In both blends, the polymer patterns comprise laterally-phase separated regions surrounded by vertically separated bilayers. We hypothesize that the observed patterns are formed by template-induced dewetting of the bottom layer of a polymer bilayer during the spin-coating process. We compare the effects of template feature size and spacing on the resulting polymer patterns with predictions from published models of template-directed dewetting in thin films and find the data in good agreement. For both blends we observe that a minimum feature size is required to nucleate dewetting/phase separation. We find this minimum template diameter to be approximately 180 nm in 50/50 PS/P2VP blends, and approximately 100 nm in 50/50 PS/P3HT blends. For larger template diameters, PS/P2VP blends show evidence for pattern formation beginning at the template boundaries, while PS/P3HT blends rupture randomly across the template features.  相似文献   

17.
Phase separation in both thin and thick films of polystyrene (PS) and poly(vinyl methyl ether) (PVME) was studied by small-angle laser light scattering (SALLS), atomic force microscopy (AFM), optical microscopy, and X-ray photoelectron spectroscopy (XPS). Blend films with controlled thickness were obtained by spin-coating polymer-toluene solutions with various concentrations. Films with thicknesses smaller and larger than the maximum wavelength of concentration fluctuations were considered. Morphology of the blend films was characterized during and after phase separation. The obtained peculiar morphology was related to surface enrichment with the lower-surface-energy component, as was verified by XPS analyses.  相似文献   

18.
The present study investigated the transient formation of water-in-oil (W/O) emulsions of sodium bis(2-ethylhexyl) sulfosuccinate (aerosol OT, AOT) in a dodecane/water interfacial region and the anomalous uptake of water in the dodecane phase by in situ bright-field optical microscopy and water concentration measurements in detail. The hydrodynamic radius of the individual W/O emulsions in the dodecane phase was determined to be 0.1-1.2 μm from the analysis of their diffusion behavior; they are much larger than common W/O microemulsions (a few nanometers in radius). At first, they were formed spontaneously in the dodecane/water interfacial region without shaking, and they diffused away into the dodecane phase. Then, almost all of them vanished at the interface by fusion. Their number and the water concentration in the dodecane phase increased first and then decreased gradually. The formation mechanism was discussed with estimated concentration profiles of AOT and water molecules, which suggests that larger W/O emulsions of 0.01-0.44 μm in radius can be formed in the dodecane phase near the interface (within 2 μm) because the concentration of AOT becomes lower than that of water there.  相似文献   

19.
Thin films of polystyrene (PS)/poly(ε-caprolactone) (PCL) blends were prepared by spin-coating and characterized by tapping mode force microscopy (AFM). Effects of the relative concentration of PS in polymer solution on the surface phase separation and dewetting feature size of the blend films were systematically studied. Due to the coupling of phase separation, dewetting, and crystallization of the blend films with the evaporation of solvent during spin-coating, different size of PS islands decorated with various PCL crystal structures including spherulite-like, flat-on individual lamellae, and flat-on dendritic crystal were obtained in the blend films by changing the film composition. The average distance of PS islands was shown to increase with the relative concentration of PS in casting solution. For a given ratio of PS/PCL, the feature size of PS appeared to increase linearly with the square of PS concentration while the PCL concentration only determined the crystal morphology of the blend films with no influence on the upper PS domain features. This is explained in terms of vertical phase separation and spinodal dewetting of the PS rich layer from the underlying PCL rich layer, leading to the upper PS dewetting process and the underlying PCL crystalline process to be mutually independent.  相似文献   

20.
采用原子力显微镜观测了由四氢呋喃和2-丁酮分别作为共溶剂制备得到的聚苯乙烯/聚甲基丙烯酸甲酯(PS/PMMA)共混物薄膜的表面形貌.研究发现,溶剂效应对共混物薄膜的表面形貌有较大影响,表面形貌中凸起与凹坑的组分分布是由溶剂效应决定的,与组分比无关.溶剂对不同组分的溶解能力不同还可以导致薄膜表面相逆转点的偏移.  相似文献   

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