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141.
Zahra Talebpour Mehregan Safari Fatemeh Molaabaci Ali Alizadeh Hassan Y. Aboul-Enein 《Chromatographia》2010,72(7-8):707-712
A novel poly(methyl methacrylate–ethyleneglycol dimethacrylate–acrylic acid) film has been introduced for coating on stir bars to sorptive extraction (SBSE). The effects of different contents of porogen, monomer, cross-linker, modifier and initiator during the solvent or bulk polymerization step on the mechanical property and solvent resistant of prepared sorptive stir bars were investigated. The evaluation of results were caused to obtain the four prepared sorptive stir bars with good mechanical stability and excellent resistance to organic solvents. The extraction efficiency of these prepared sorptive stir bars were investigated by liquid desorption-liquid chromatography-ultraviolet detection (LD-LC-UV) using N-Nitrosodiphenylamine as target analyte. SBSE assays showed the sorptive stir bar that prepared using solution polymerization method had the better recovery for N-Nitrosodiphenylamine in water samples. This sorptive stir bar showed good linearity and acceptable recoveries, as well as advantages such as sensitivity, simplicity, low cost and high feasibility. Based on atomic force microscopy (AFM) results, the average pore size of optimum prepared stir bar using solvent polymerization method was obtained ~9 nm. The thermal gravity (TG) and differential scanning calorimetric (DSC) results showed this polyacrylate film has high thermal stability. 相似文献
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We show that it is possible to use hard-Pomeron behavior to the gluon distribution and singlet structure function at low x. We derive a second-order independent differential equation for the gluon distribution and the singlet structure function.
In this approach, both singlet quarks and gluons have the same high-energy behavior at small x. These equations are derived from the next-to-leading order DGLAP evolution equations. All results can be consistently described
in the framework of perturbative QCD, which shows an increase of gluon distribution and singlet structure functions as x decreases. 相似文献
146.
M.J. KarimiG. Rezaei 《Physica B: Condensed Matter》2011,406(23):4423-4428
In this work, influences of external electric and magnetic fields on the optical rectification coefficient, the linear and the third-order nonlinear optical absorption coefficients as well as refractive index changes of finite semi-parabolic quantum dots are investigated. In this regard, energy eigenvalues and eigenfunctions of the system are calculated numerically, and optical properties are obtained using the compact density matrix approach. The results show that external electric and magnetic fields have a great influence on these optical quantities. 相似文献
147.
The major objective of this work was the development of a reliable model to describe volumetric properties of ionic liquids
(ILs). In this regard, we have applied the Ihm–Song–Mason equation of state (EOS) to some phosphonium- and imidazolium-based
ILs. Three temperature-dependent parameters in the equation of state have been scaled based on the surface tension and the
liquid density at room temperature. In order to improve the predictive power of the mentioned EOS for ILs, we have proposed
using a simple modification. We have taken 1,228 experimental points to show the reliability of the improved EOS. The comparison
of predicted densities with literature data over a broad range of temperature, 293–472 K, and pressures up to 200 MPa led
to encouraging results. The average absolute deviation of calculated densities from literature values was found to be 0.75%. 相似文献
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Soleyman Hosseinzadeh Shahryar Pashaei Younes Saadat Zahra Khodaparast Roshan Javanifar Masoud Mohamadpour Alireza Hosseinzadeh 《Polymer Science Series B》2017,59(5):544-550
Cross-linked polystyrene (PS) particles having red blood corpuscle (RBC)-like shape were synthesized by one-pot dispersion polymerization of styrene with ethanol/water mixture and ethylene glycol dimethacrylate (EGDMA) as the reaction medium and cross-linker, respectively. Monitoring of the reaction showed that RBC-like shape forms due to asymmetric shrinkage of a cross-linked network during the phase separation. In addition, three dimensional phase diagram was generated based on the yielded data that showed that the formation of such unique shape extremely depends on the polarity of the medium and injection time of the cross-linker. In situ synthesis of RBC-like particles, as promising biomaterials in targeted drug delivery and a model for the understanding of the cell behavior, via such fast and high solid content approach makes it to be conducive to subsequent scale up, i.e. potential commercial adoption. 相似文献