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971.
972.
P. Hashemi M. M. Abolghasemi A. R. Fakhari S. N. Ebrahimi S. Ahmadi 《Chromatographia》2007,66(3-4):283-286
A new, simple hydrodistillation–solvent microextraction (HD–SME) technique has been used for analysis of the volatile components
of the aerial parts of Artemisia aucheri. The components were collected in a single microdrop, and this was injected directly for gas chromatographic–mass spectrometric
(GC–MS) analysis. The effects on extraction efficiency of extraction solvent, sample mass, microdrop volume, and extraction
time were optimized by use of a simplex method. The identities of the components of HD–SME extracts were confirmed according
to their retention indexes and mass spectra with those of standards. Forty components were extracted and identified by use
of the method; 1,8-cineol (22.8%), chrysanthenone (18.16%), α-pinene (8.33%), and mesitylene (7.41%) were the major constituents.
The results obtained from the microextraction method were compared with those obtained by conventional hydrodistillation. 相似文献
973.
Bio‐based copolymers obtained through miniemulsion copolymerization of methyl esters of acrylated fatty acids and styrene
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Fabricio Machado Joel C. Rubim Timothy F. L. McKenna 《Journal of polymer science. Part A, Polymer chemistry》2017,55(8):1422-1432
Polymers based on renewable sources are promising materials, and can find many uses in coatings and adhesive applications. The goal of this work was to synthesize and characterize bio‐based styrene/acrylated fatty acid methyl ester (AFAME) copolymer—poly(styrene‐co‐AFAME) prepared by miniemulsion polymerization. The main strategy adopted was to functionalize the bio‐monomer with acrylic acid that was confirmed by 1H NMR and FTIR measurements, to allow its free‐radical homo‐ or copolymerization with styrene. Poly(styrene‐co‐AFAME) with different AFAME content were obtained and their composition were evaluated by 1H NMR. Dynamic light scattering measurements throughout the reactions have indicated a very stable colloidal systems and average particles size ranges 100–150 nm. The structural and physical properties of poly(styrene‐co‐AFAME) were investigated by DTG‐DTA, DSC which displayed a decreasing of glass transition temperature with increase of AFAME content. The results showed in this study have indicated that the poly(styrene‐co‐AFAME) can be used in several fields because their characteristics are totally distinct. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 1422–1432 相似文献
974.
975.
熔盐热裂解大豆油的特性研究 《燃料化学学报》2013,41(11):1316-1321
以大豆油为原料,在ZnCl2-KCl熔融盐体系中考察了进料速量、载气流量、反应温度及进料量对其热裂解的影响。采用气相色谱-质谱联用仪(GC-MS)表征生物油组成。结果表明,进料速量和载气流量主要通过改变大豆油的反应停留时间影响裂解效果。当进料速率为1.2 g/min及不通载气时,大豆油停留时间较长,裂解较充分;随着温度升高,生物油得率增大,含氧化合物含量及酸值上升;随着进料量增大,生物油得率稳定在70%左右,但脱羧效果有所下降。经过催化加氢,生物油性质得到了明显的改善,组分分布与0#柴油分布大体相似。 相似文献
976.
Hao Huang R. Chick Wattenbarger Xiuli Gai William P. Brown Owen J. Hehmeyer Jianlin Wang Ted A. Long 《国际流体数值方法杂志》2013,71(6):671-686
In this paper, the geomechanical factors that may affect injection processes in heavy oil recovery are investigated. To accurately capture the geomechanical effects, we employed a numerical formulation that allows fully coupling of nonlinear geomechanical deformation and multicomponent porous media flows. Two salient features of this new coupling formulation are the following: (1) all flow and geomechanical equations are solved implicitly in one single matrix equation, and (2) it allows reuse of matrices from both a traditional fully implicit multicomponent reservoir simulator and a nonlinear geomechanics simulator. The former feature ensures stable coupling between the reservoir flow and geomechanics, and the latter significantly reduces the programming work. Numerical examples are given to demonstrate the accuracy and convergence performance of the new formulation. The proposed formulation is then applied to model injection into heavy oil reservoirs. The numerical investigation revealed that geomechanical factors, such as in situ stress anisotropy and the uneven deformation of reservoir rock and attached impermeable rock, can result in skewed or nonuniform plastic strain and, hence, alter the sweep of the injected fluid. Coupled geomechanics simulation also gives rather different transient pressure response from that of uncoupled simulation. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
977.
分析了我国现存监管手段的不足,针对实际监管要求,基于信息化技术的快速发展及物联网技术在其他领域的成功应用,提出海上原油过驳的智慧监管体系的总体构架,并阐述了有关功能,为以后建设基于物联网技术的海上原油过驳智慧监管体系提供了参考。 相似文献
978.
The reservoir characteristics and fluid property of Daqing reservoir were taken as the research platform. For simulating the emulsifying process in the reservoir, injecting different concentrations of emulsifier solution into the core after water flooding, the viscoelasticity of the emulsion was measured. According to the value of the emulsion viscoelasticity, the numerical model of emulsion displacing oil film was established. Elastic stress acting on the oil film was calculated when the emulsion migrates. The deformation and transportation of the oil film were analyzed at bearing the elastic stress. The results show that the emulsion has favorable viscoelasticity. When the emulsifier concentration is higher, the emulsion elasticity is favorably increased. The oil film can deform and transport forward by the elastic stress. The elastic stress increases as the emulsion elasticity increases. 相似文献
979.
980.
P.S. SathiskumarGiridhar Madras 《Polymer Degradation and Stability》2011,96(9):1695-1704
A new family of castor oil based biodegradable polyesters was synthesized by catalyst free melt condensation reaction between two different diacids and castor oil with d-mannitol. The polymers synthesized were characterized by NMR spectroscopy, FT-IR and the thermal properties were analysed by DSC. The results of DSC show that the polymer is rubbery in physiological conditions. The contact angle measurement and hydration test results indicate that the surface of the polymer is hydrophilic. The mechanical properties, evaluated in the tensile mode, shows that the polymer has characteristics of a soft material. In vitro degradation of polymer in PBS solution carried out at physiological conditions indicates that the degradation goes to completion within 21 days and it was also found that the rate of degradation can be tuned by varying the curing conditions. 相似文献