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211.
Marjan Ghorbani Farideh Mahmoodzadeh Behrooz Jannat Nazila Fathi Maroufi Behnam Hashemi Leila Roshangar 《先进技术聚合物》2019,30(7):1847-1855
Cancer is one of the health problems that lead to death in the world, and nanotechnology was shown to have a unique potential to improve the therapeutic efficacy of anticancer agents. The nanosized drug delivery systems (DDSs) have been offered for targeting tumor tissue because of enhanced drug bioavailability and long circulation time. In this context, we reported a facial approach to prepare a novel pH and glutathione‐responsive nanogel. After that, the nanocarriers coupled with highly fluorescent quantum dots were developed. Then methotrexate (MTX) was loaded into and on the surface of nanogels by ionic interaction so that the triggered MTX release ability of the synthesized nanocarriers was verified through the assessment of in vitro drug release at simulated tumor tissue condition. The improved efficiency of the developed nanogels and their targeted performance via conjugation of MTX (as target ligand of folate receptors) were investigated through the various cell cytotoxicity studies such as 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay, 4′6‐diamidino‐2‐phenylindole (DAPI) staining, and flow cytometry. The results of various cell cytotoxicity studies concluded that the developed smart nanogels have many promising abilities for the targeted MTX delivery to cancer tissues. 相似文献
212.
A new one-pot procedure for the efficient synthesis of novel 3,4-dihydrocoumarin derivatives using commercially available substituted 2-hydroxybenzaldehydes, Meldrum's acid, and isocyanides by a three-component condensation reaction in dichloromethane at room temperature without using any catalysts and activation was developed. 相似文献
213.
We propose public-key encryption algorithms based on chaotic maps, which are generalization of well-known and commercially used algorithms: Rivest-Shamir-Adleman (RSA), ElGamal, and Rabin. For the case of generalized RSA algorithm we discuss in detail its software implementation and properties. We show that our algorithm is as secure as RSA algorithm. 相似文献
214.
Marjan?MatvejchukEmail author Anna?Ionova 《International Journal of Theoretical Physics》2005,44(12):2231-2238
Let
be a Hilbert space with an inner product
. In Jajte, R., and Paszkiewicz, A. (1978, Vector measure on the closed subspaces of a Hilbert space, Studia Mathematica
63, 229–251), the
-measure on the logic of all orthogonal projections on
H was studied. We examine the
-measure on the hyperbolic logic of all J-projections on a Krein space.
PACS: 03.65.Ta, 03.65.Db, 03.65.Ca. 相似文献
215.
216.
Marjan Jerman 《Algebra Universalis》2002,48(4):485-496
Let A be an Archimedean uniformly complete f-algebra with unit element. It is shown that A is a po-coherent ring (in the sense of F. Wehrung) if and only if A is Dedekind σ-complete.
Received June 7, 2001; accepted in final form September 1, 2002. 相似文献
217.
Certain types of samples contain chloride in concentrations that are too high to accurately determine other anions by ion chromatography without any pretreatment. One of the most widely used approaches for such samples is matrix elimination using disposable cartridges containing a cation-exchange resin in the Ag+ form. The efficiency and characteristics of the commercially available cartridge for Cl- removal were tested by the on-line connection of the cartridge effluent to an inductively coupled plasma mass spectrometer. Displacement efficiency of Ag+ ions and loading capacity of the cartridges were studied at different flow-rates. Significant amounts of silver were detected in the effluent, which were attributed to colloidal AgCl as well as dissolved Ag+ ions. Because silver ions can cause irreversible damage to the analytical column, an Ag cartridge followed by an on line filter (pore size 0.22 microm) and cartridge in the H3O+ form were proposed for improvement of this sample pretreatment technique for chloride removal. 相似文献
218.
Synthesis of Carbon Quantum Dots Nanoparticles by Cyclic Voltammetry and Its Application as Methanol Tolerant Oxygen Reduction Reaction Electrocatalyst
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Carbon quantum dot (CQD) nanoparticles are synthesized by one‐step electrochemical method, cyclic voltammetry (CV), at different potentials using graphite rods and NaOH/EtOH as electrolyte. The electro‐chemically manufactured CQD is characterized by Transmission electron microscopy, Ultra violet absorption, X‐ray diffraction and Fourier transform infrared spectrometry. The morphology and microstructure methods confirm the formation of high quality CQD. Finally, we design a new gas diffusion electrode (GDE) based on CQD pasted on carbon paper for the oxygen reduction reaction at cathode side as methanol tolerance in direct methanol fuel cell and compared it with standard Pt‐C catalysts using cyclic voltammetry and linear sweep voltammetry. The ORR results in presence of methanol indicate that the GDE prepared from CQD exhibits methanol tolerance compared to the GDE prepared from Pt/C (Electrochem). 相似文献
219.
Marjan A. Rafiee 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(13):2571-2575
Quadrupolar parameters of nuclei can be used as a tool to understand the electronic structure of compounds. Lithium alanate (LiAlH4) is a potential hydrogen storage material because of its high capacity of 10.5 wt % H2. However, the drawbacks of its dehydrogenation process are the relatively high temperatures and the slow dehydrogenation kinetics; furthermore, its reversibility is rather poor. Understanding the bonding nature of Al and H is essential for improving its dehydrogenation performance. In this work the charge density distribution in LiAlH4 is studied. Thus using calculated nuclear quadrupole coupling constants of hydrogens (2H-NQCCs), the electronic structure of α-LiAlH4 with high pressure forms of LiAlH4, (β- and γ-LiAlH4) were compared. The results show that easier condition for dehydrogenation is expected in β-LiAlH4. Comparison of calculated dehydrogenation enthalpies of LiAlH4 phases verifies this prediction. The electric field gradient (EFG) of quadrupolar nuclei were calculated to obtain NQCC parameters. All calculations performed using Gaussian 03 at B3LYP/6-31G* level of theory. 相似文献
220.
Kristl J Veber M Krajnicic B Oresnik K Slekovec M 《Analytical and bioanalytical chemistry》2005,383(5):886-893
A new method is described for the determination of endogenous jasmonic acid (JA) in Lemna minor plant extracts using liquid chromatography (LC) with fluorescence detection. Plant tissues were extracted and derivatised
using 9-anthryldiazomethane (ADAM reagent) prepared in situ. Accuracy and precision were improved by using the internal standard
dihydrojasmonic acid (dh-JA) for the correction of JA losses during sample preparation steps. Liquid chromatography–mass spectrometry
(LC/MS) analysis of ADAM derivatives of JA and dh-JA confirmed that a single molecule of JA and dh-JA was coupled with one
molecule of reagent. Derivatives of JA and dh-JA were separated with gradient elution on a C18 reversed-phase column using acetonitrile/water as a mobile phase and detected by a fluorescence detector at excitation and
emission wavelengths of 254 and 412 nm, respectively. The detection limits of JA and dh-JA were 2.9 ng mL−1 and 3.7 ng mL−1 per 50-μL injection. The method is reproducible and selective and yields single peaks for each compound regardless of isomer.
The specificity and accuracy of the proposed LC/FD method was confirmed by liquid chromatography–TurboIon Spray tandem mass
spectrometric (LC/MS/MS) analysis of free JA in Lemna minor samples under multiple reaction monitoring conditions. 相似文献