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151.
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153.
Poly[2-(4-chlorophenyl)-1,3-dioxolan-4-yl]methyl acrylate,poly(CPhDMA),was synthesized with radical polymerization process using 2,2′-azobisisobutyronitrile as radical initiator in 1,4-dioxane at 60℃.The structure of poly(CPhDMA) was confirmed by means of UV-Vis,FT-IR,1H-NMR,and 13C-NMR spectral techniques.The molecular weight distribution values of the polymer were determined with gel permeation chromatography(GPC).The number-average molecular weight(Mn),weight-average molecular weight(MW) and polydispersity index(PDI) values of poly(CPhDMA) were determined to be 10300,21600 and 2.097,respectively.The thermal degradation kinetics of the polymer was investigated by using TG/DTG-DTA and DSC analyses at different heating rates in dynamic nitrogen atmosphere.The apparent activation energy values obtained by Flynn-Wall-Ozawa and Friedman methods were found to be 91.68 and 85.23 kJ mol-1,respectively,for thermal decomposition of poly(CPhDMA).Also,the thermal degradation activation energy value of poly(CPhDMA) was calculated by using the Kissinger method based on the DTG,DTA and DSC data.Then the mechanism function of it was determined by master plots method.Finally,electrical and optical properties of poly(CPhDMA) were determined by four-point probe and UV-Vis techniques,respectively. 相似文献
154.
Gulmira Özek Fatih Demirci Temel Özek Nurhayat Tabanca David E. Wedge Shabana I. Khan Kemal Hüsnü Can Başer Ahmet Duran Ergin Hamzaoglu 《Journal of chromatography. A》2010,1217(5):741-748
Four different isolation techniques, conventional hydrodistillation (HD), microwave-assisted hydrodistillation (MWHD), microdistillation (MD) and micro-steam distillation-solid-phase microextraction (MSD-SPME), have been used to analyze the volatile constituents from the aerial parts of Salvia rosifolia Sm. by gas chromatography and gas chromatography coupled to mass spectrometry. HD and MWHD techniques produced quantitatively (yield, 0.39% and 0.40%) and qualitatively (aromatic profile) similar essential oils. α-Pinene (15.7–34.8%), 1,8-cineole (16.6–25.1%), β-pinene (6.7–13.5%), β-caryophyllene (1.4–5.0%) and caryophyllene oxide (1.4–4.4%) were identified as major constituents of this Turkish endemic species. Besides, the hydrodistilled oil of S. rosifolia was evaluated for antibacterial, antifungal, anticancer, antioxidant and cytotoxic activities. The hydrodistilled oil of S. rosifolia showed antibacterial activity against Methicillin-resistant Staphylococcus aureus (MRSA) with a MIC value of 125 μg/mL. Other human pathogenic microorganisms (Escherichia coli, Pseudomonas aeruginosa, Enterobacter aerogenes, Salmonella typhimurium, Staphylococcus epidermidis, Candida albicans) were also inhibited within a moderate range (MIC = 125–1000 μg/mL). Antifungal activity of the oil was also observed against the strawberry anthracnose-causing fungal plant pathogens Colletotrichum acutatum, C. fragariae and C. gloeosporioides. No cytotoxicity was observed for S. rosifolia oil up to 25 mg/mL against malignant melanoma, epidermal, ductal and ovary carcinoma. 相似文献
155.
Crystal Structure of 4-Bromo-3,4-Dichloro-1-(1-Morpholinyl)-1-(Decylsulfanyl)-2-Nitro-Buta-1,3-Diene
Cemil Ibis Nahide Gulsah Deniz Amac Fatih Tuyun 《Journal of chemical crystallography》2010,40(4):353-356
Abstract
The compound 4-bromo-3,4-dichloro-1-(1-morpholinyl)-1-(decylsulfanyl)-2-nitro-buta-1,3-diene was synthesized from the reaction of 4-bromo-1,3,4-trichloro-1-(decylsulfanyl)-2-nitro-buta-1,3-diene with morpholine and characterized by elemental analysis, IR spectrum, UV spectra, 1H NMR,13C NMR and X-ray single crystal determination. In the title compound, C18H29BrCl2N2O3S, crystallizes in the monoclinic space group P21/c, a = 15.8326(4) Å, b = 8.9915(10) Å, c = 16.7528(5) Å, β = 100.808(10)°, V = 2,342.6(3) Å3, Z = 4, R 1 = 0.0590 and wR 2 = 0.0940. The morpholine ring adopts a chair conformation. The morpholine ring and the butadiene group are inclined at an angle of 113.4 (1)°. The butadiene unit is not planar as can be expected if the two double bonds are fully conjugated. 相似文献156.
研究了掺杂两种分散染料橙的向列型液晶E7的性质以及碳纳米粒子(单壁碳纳米管或富勒烯C60)的影响. 两种分散染料橙11和13具有较高的溶解度和有序参数,被作为掺杂剂同时使用. 与掺杂单染料相比,同时加入两种染料橙使液晶的有序参数明显提高. 与纯液晶相比,掺杂可引起向列相向各向同性相转变温度的升高. 相似文献
157.
In this study, a single, simple and an accurate computer-aided design model is developed in order to obtain the injection level dependence of the critical quantities of broad-area (with a width of 50 μm or more) InGaAs deep quantum-well (QW) lasers. Each of these quantities (gain, refractive index variation, and alpha (α) parameter) requires lengthy mathematical calculations with the use of different theories, assumptions, approximations, and estimations of some parameter values. The model is based on artificial neural network (ANN) approach that the total computational time is in the order of microseconds for the whole quantities in order to get their accurate values. The results are in very good agreement with the previously obtained results from an InGaAs deep QW laser sample. 相似文献
158.
We studied the effect of an organic surfactant, dextrin, concentration on structural, morphological and optical properties of nanostructured CdO films deposited on glass substrates by using an easy and low-cost SILAR method. Microstructures of the nanostructured CdO films were optimized by adjusting dextrin concentration. XRD, SEM and UV–Vis Spectroscopy were used to study phase structure, surface morphology and optical properties of CdO films. Furthermore, effects of dextrin concentration on the surface roughness characteristics of CdO samples were reported. The results showed that the presence of organic surfactant highly affected the physical properties of CdO nanomaterials. 相似文献
159.
This is the first study to consider a quantum dot with screw dislocation that has Rosen-Morse (RM) confinement potential, generated by a GaAs/GaAlAs heterostructure. An external magnetic field and Aharonov-Bohm (AB) flux field were also applied on RM quantum dot (RMQD) in order to stave the effects of a screw dislocation defect. The combined effect of the screw dislocation defect, the external magnetic field, and AB flux field on the total refractive index changes (TRICs) and the total absorption coefficients (TACs) of RMQD are thus investigated. Cylindrical coordinates are used due to the direction of application of the torsion and the external fields, as well as due to the structure's symmetry. The effective mass approximation and tridiagonal matrix methods are used in order to obtain the subband energy spectra and electronic wave functions of RMQD. The nonlinear optical specifications of RMQD are checked using compact-density-matrix formalism within the framework of the iterative method. Reviews without screw dislocation are also carried out in order to be able to clarify the effects of a screw dislocation defect on the optical properties, and then, both cases are deliberated. This study is the first attempt to analyze the AB flux field for RMQD without screw dislocation. In the present study, the influences of a screw dislocation defect on RMQD's TRICs and TACs are probed by considering different values of the external magnetic field and AB flux field, and the ranges of corresponding parameters on the optimum of the structure are specified. Moreover, the study also elucidates how to rule out the effects of screw dislocation on optical specifications by means of the external fields. Despite a certain screw dislocation, the frequency range is determined where the structure behaves as if it is perfect (namely, without screw dislocation) for its optimum, which in turn is crucial for experimental applications. 相似文献
160.
Ö. Alver C. Parlak M. Fatih Kaya G. Dikmen L. Genç 《Journal of Structural Chemistry》2014,55(3):438-445
FT-IR and Raman spectra of methyl(5-[2-thienylcarbonyl]-1H-benzimidazol-2-yl (nocodazole) are experimentally examined in the region of 4000–400 cm?1. The optimized geometric parameters, conformational equilibria, normal mode frequencies, and corresponding vibrational assignments of nocodazole (C14H11N3O3S) calculated by means of the B3LYP hybrid density functional theory (DFT) method using the 6-31++G(d,p) basis set. Vibrational assignments are made based on the total energy distribution (TED) and the thermodynamic functions, highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO) of nocodazole are calculated. Calculations are employed for four energetically possible conformers of nocodazole (N1, N2, N3, and N4) in the gas phase. A comparison between the experimental and theoretical results indicates that the B3LYP method is able to provide satisfactory results for predicting vibrational wavenumbers if calculated values are scaled properly and the structural parameters. 相似文献