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21.
In this work, the preparation of micron-sized polymer particles with nonspherical shapes via seeded dispersion polymerization of 2-ethylhexyl methacrylate with polystyrene seed particles in the presence of hydrocarbon droplets and evaporation of hydrocarbon after the polymerization under various polymerization conditions was discussed. The effect of second monomer and initiator type, mixing method, and stabilizer content on the shape of the obtained particles was investigated. It was observed that particles with more nonspherical shapes were obtained with increasing the alkyl chain length of ester group of the methacrylate of the second monomer which is because of increasing the absorption amounts of hydrocarbon by second polymer domains. Moreover, the experimental results showed that shape of the particles which was produced by shaking is more nonspherical than the shape of the particles which was obtained from tumbling. Furthermore, particles with different nonspherical shapes were prepared by changing the initiator type and stabilizer content.  相似文献   
22.
Journal of Thermal Analysis and Calorimetry - Two coordination polymers (CPs) material, [Zn(μ-Cl)2(μ-bpy)]∞ (bpy?=?4,4′-bipyridine) and [Cu(bpy)(phen)(ClO4)2]n...  相似文献   
23.
In this article, we introduce a new orderly backtrack algorithm with efficient isomorph rejection for classification of t‐designs. As an application, we classify all simple 2‐(13,3,2) designs with nontrivial automorphism groups. The total number of such designs amounts to 1,897,386. The decomposability of the designs is also considered. © 2005 Wiley Periodicals, Inc. J Combin Designs 14: 479–489, 2006  相似文献   
24.
Methylglycine, also known sarcosine, is dramatically used in drug molecules and its metal complexes can interact to DNA and also do cleavage. Hence, to study the influence of methylglycine ligand on biological behavior of metal complexes, two water-soluble platinum (II) complexes with the formula cis-[Pt(NH3)2(CH3-gly)]NO3 and cis-[Pt(NH2-CH3)2(CH3-gly)]NO3 (where CH3-gly is methylglycine) have been synthesized and characterized by spectroscopic methods, molar conductivity measurements, and elemental analyzes. The anticancer activity of synthesized complexes was tested against human breast adenocarcinoma cell line of MCF7 using MTT assay and results showed excellent anticancer activity with Cc50 values of 126 and 292 μM after 24 h incubation time, for both complexes of cis-[Pt(NH3)2(CH3gly)]NO3 and cis-[Pt(NH2-CH3)2(CH3gly)]NO3, respectively. Also, the interaction between Pt(II) complexes with calf thymus DNA was extensively studied by means of absorption spectroscopy, fluorescence titration spectra displacement with ethidium bromide (EtBr), and circular dichroism studied in Tris-buffer. The obtained spectroscopic results revealed that two complexes can bind to highly polymerized calf thymus DNA cooperatively and denature at micromolar concentrations. The fluorescence data indicate that quenching effect for cis-[Pt(NH3)2(CH3gly)]NO3 (Ksv?=?9.48 mM?1) was higher than that of cis-[Pt(NH2-CH3)2(CH3gly)]NO3 (Ksv?= 1.98 mM?1). These results were also confirmed by circular dichrosim spectra. Consequently, docking data showed that cis-[Pt(NH3)2(CH3gly)]NO3 with more interaction energy binds on DNA via groove binding which is more compatible with experimental results.
Graphical Abstract ? Two anticancer Pt(II) complexes, cis-[Pt(NH3)2(CH3gly)]NO3 and cis-[Pt(NH2?CH3)2(CH3gly)]NO3, have been synthesized and interacted with calf thymus DNA. Improving solubility of these compounds reduce side effects and increase anticancer activity against human breast cell line. Modes of binding have been studied by electronic absorption, fluorescence, and CD measurements. Results show that both Pt(II) complexes can interact to DNA via groove binding.
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25.
Novel magnetic titanium dioxide nanoparticles decorated with methyltrimethoxysilane (Fe3O4@TiO2‐MTMOS) were successfully fabricated via a sol–gel method at room temperature. The synthesized material was characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, thermogravimetric analysis and vibrating sample magnetometry. The removal efficiency of the adsorbent was evaluated through the adsorption of methylene blue (MB) dye from water samples. The adsorption isotherm and kinetics were evaluated using various models. The Langmuir model indicated a high adsorption capacity (11.5 mg g?1) of Fe3O4@TiO2‐MTMOS. The nanocomposite exhibited high removal efficiency (96%) and good regeneration (10 times) compared to Fe3O4 and Fe3O4@TiO2 at pH = 9.0. Based on the adsorption mechanism, electrostatic interaction plays a main role in adsorption since MB dye is cationic in nature at pH = 9, whereas the adsorbent acquired an anionic nature. The newly synthesized Fe3O4@TiO2‐MTMOS can be used as a promising material for efficient removal of MB dye from aqueous media.  相似文献   
26.
Journal of Russian Laser Research - In this paper, we use laser-induced breakdown spectroscopy (LIBS) to investigate the laser-induced copper plasma with and without an external magnetic field,...  相似文献   
27.
This paper studies dispersive optical solitons that are governed by the Schrödinger-Hirota equation with power law nonlinearity. The G′/G-expansion method is applied to extract soliton solution to this equation. This approach reveals dark 1-soliton solution to the equation.  相似文献   
28.
Non-additive measure is a generalization of additive probability measure. Integral inequalities play important roles in classical probability and measure theory. Some well-known inequalities such as the Minkowski inequality and the H?lder inequality play important roles not only in the theoretical area but also in application. Non-additive integrals are useful tools in several theoretical and applied statistics which have been built on non-additive measure. For instance, in decision theory and applied statistics, the use of the non-additive integrals can be envisaged from two points of view: decision under uncertainty and multi-criteria decision-making. In fact, the non-additive integrals provide useful tools in many problems in engineering and social choice where the aggregation of data is required. In this paper, H?lder and Minkowski type inequalities for semi(co)normed non-additive integrals are discussed. The main results of this paper generalize some previous results obtained by the authors.  相似文献   
29.
30.
J. Biazar  M. Eslami 《Physics letters. A》2010,374(29):2904-2906
In this article differential transform method (DTM) is considered to solve Telegraph equation. This method is a powerful tool for solving large amount of problems (Zhou (1986) [1], Chen and Ho (1999) [2], Jang et al. (2001) [3], Kangalgil and Ayaz (2009) [4], Ravi Kanth and Aruna (2009) [5], Arikoglu and Ozkol (2007) [6]). Using differential transform method, it is possible to find the exact solution or a closed approximate solution of an equation. To illustrate the ability and reliability of the method some examples are provided. The results reveal that the method is very effective and simple.  相似文献   
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