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排序方式: 共有206条查询结果,搜索用时 31 毫秒
171.
Danijela V. Brković Vesna V. Kovačević Goran B. Sretenović Milorad M. Kuraica Nemanja P. Trišović Luca Valentini Aleksandar D. Marinković José M. Kenny Petar S. Uskoković 《Journal of Physics and Chemistry of Solids》2014
Multi-walled carbon nanotubes (MWCNTs) and graphene nanoplatelets (GNPs) have been functionalized by dielectric barrier discharge (DBD) in air. The extent of functionalization of MWCNTs and GNPs reaches a maximum at the delivered discharge energy of 720 and 240 J mg−1, respectively. Further exposure to plasma leads to reduction of functional groups from the surface of the treated nanomaterials. It has also been demonstrated that DBD plasma does not produce dramatic structural changes in MWCNTs, while flakes of the treated GNPs become thinner and smaller in the lateral size. Conductive thin films, obtained by drop casting a solution of the treated nanomaterials in N-methyl-1-pyrrolidone on poly(methyl methacrylate) substrate, show significantly lower sheet resistance. 相似文献
172.
173.
174.
Petar Petrov 《分析论及其应用》2003,19(2):153-159
AbstractFor given data (t_i,y_i),i=0, 1,…,n,0=t_0相似文献
175.
Thomas Kappeler Alberto Maspero Jan Molnar Peter Topalov 《Communications in Mathematical Physics》2016,346(1):191-236
Motivated by perturbation theory, we prove that the nonlinear part \({H^{*}}\) of the KdV Hamiltonian \({H^{kdv}}\), when expressed in action variables \({I = (I_{n})_{n \geqslant 1}}\), extends to a real analytic function on the positive quadrant \({\ell^{2}_{+}(\mathbb{N})}\) of \({\ell^{2}(\mathbb{N})}\) and is strictly concave near \({0}\). As a consequence, the differential of \({H^{*}}\) defines a local diffeomorphism near 0 of \({\ell_{\mathbb{C}}^{2}(\mathbb{N})}\). Furthermore, we prove that the Fourier-Lebesgue spaces \({\mathcal{F}\mathcal{L}^{s,p}}\) with \({-1/2 \leqslant s \leqslant 0}\) and \({2 \leqslant p < \infty}\), admit global KdV-Birkhoff coordinates. In particular, it means that \({\ell^{2}_+(\mathbb{N})}\) is the space of action variables of the underlying phase space \({\mathcal{F}\mathcal{L}^{-1/2,4}}\) and that the KdV equation is globally in time \({C^{0}}\)-well-posed on \({\mathcal{F}\mathcal{L}^{-1/2,4}}\). 相似文献
176.
This paper deals with the periodic solutions of the Cauchy problem to the Burgers-Hopf equation containing small viscosity
term. We propose at first an explicit formula for the exact solution of the Cauchy problem and then we give an approximate
formula. We use CNN approach for constructing the approximate solution and we find precise estimates of the remainder term.
This work was supported by the NATO Grant ICS.NR.CLG 981757. 相似文献
177.
González S Petrović M Radetic M Jovancic P Ilic V Barceló D 《Rapid communications in mass spectrometry : RCM》2008,22(10):1445-1454
A method based on the application of ultra-performance liquid chromatography (UPLC) coupled to hybrid quadrupole-time-of-flight mass spectrometry (QqTOF-MS) with an electrospray (ESI) interface has been developed for the screening and confirmation of several anionic and non-ionic surfactants: linear alkylbenzenesulfonates (LAS), alkylsulfate (AS), alkylethersulfate (AES), dihexyl sulfosuccinate (DHSS), alcohol ethoxylates (AEOs), coconut diethanolamide (CDEA), nonylphenol ethoxylates (NPEOs), and their degradation products (nonylphenol carboxylate (NPEC), octylphenol carboxylate (OPEC), 4-nonylphenol (NP), 4-octylphenol (OP) and NPEO sulfate (NPEO-SO4). The developed methodology permits reliable quantification combined with a high accuracy confirmation based on the accurate mass of the (de)protonated molecules in the TOFMS mode. For further confirmation of the identity of the detected compounds the QqTOF mode was used. Accurate masses of product ions obtained by performing collision-induced dissociation (CID) of the (de)protonated molecules of parent compounds were matched with the ions obtained for a standard solution. The method was applied for the quantitative analysis and high accuracy confirmation of surfactants in complex mixtures in effluents from the textile industry. Positive identification of the target compounds was based on accurate mass measurement of the base peak, at least one product ion and the LC retention time of the analyte compared with that of a standard. The most frequently surfactants found in these textile effluents were NPEO and NPEO-SO4 in concentrations ranging from 0.93 to 5.68 mg/L for NPEO and 0.06 to 4.30 mg/L for NPEO-SO4. AEOs were also identified. 相似文献
178.
Petrov P Yuan J Yoncheva K Müller AH Tsvetanov CB 《The journal of physical chemistry. B》2008,112(30):8879-8883
A transition from spherical to wormlike micelles of a poly(ethylene oxide) 20- block-poly(propylene oxide) 70- block-poly(ethylene oxide) 20 triblock copolymer Pluronic P123 induced by solubilization of a tetrafuctional monomer, Pentaerythritol tetraacrylate (PETA), in aqueous media has been studied. The wormlike micelles shape was locked by UV cross-linking of PETA within the micelles resulting in stabilized polymeric micelles (SPMs). The stability of SPMs in a good solvent for both polyether blocks like THF, and upon dilution below the critical micelle concentration (CMC) of P123 in water was confirmed by dynamic light scattering (DLS) and scanning force microscopy (SFM). Formation of cadmium sulfide (CdS) nanoparticles within the wormlike SPMs was carried out via the reduction of Cd (2+) with NaS and analyzed by transmission electron microscopy (TEM) and UV-vis absorption measurements. A stable water-dispersible hybrid system consisting of CdS quantum dots embedded into the wormlike SPMs was obtained. 相似文献
179.
Sarah A.E. Young Joy Muthami Mica Pitcher Petar Antovski Patricia Wamea Robert Denis Murphy Reihaneh Haghniaz Andrew Schmidt Samuel Clark Ali Khademhosseini Amir Sheikhi 《Materials Today Chemistry》2022
Cancer is one of the leading causes of death worldwide, affecting millions of people every year. Although chemotherapy remains one of the most common cancer treatments in the world, the severe side effects of chemotherapy drugs impose serious concerns to cancer patients. In many cases, the chemotherapy can be localized to maximize the drug effects; however, the drug systemic circulation induces undesirable side effects. Here, we have developed a highly efficient cellulose-based nanoadsorbent that can capture more than 6,000 milligrams of doxorubicin (DOX), one of the most widely used chemotherapy drugs, per gram of the adsorbent at physiological conditions. Such drug capture capacity is more than 3,200% higher than other nanoadsorbents, such as DNA-based platforms. We show how anionic hairy cellulose nanocrystals, also known as electrosterically stabilized nanocrystalline cellulose (ENCC), bind to positively charged drugs in human serum and capture DOX immediately without imposing any cytotoxicity and hemolytic effects. We elucidate how ENCC provides a remarkable platform for biodetoxification at varying pH, ionic strength, ion type, and protein concentration. The outcome of this research may pave the way for developing the next-generation in vitro and in vivo drug capture additives and devices. 相似文献
180.
Ivo Světlík Mihály Molnár Milan Váňa Václav Michálek Petar Stefanov 《Journal of Radioanalytical and Nuclear Chemistry》2009,281(1):137-141
Carbon from fossil CO2 emissions, without a significant presence of 14C, causes dilution of 14C in the carbon isotopic mixture (Suess effect). Reported 14C activities are usually connected to radiocarbon amount in the carbon isotopic mixture. Our paper is aimed on estimation
of 14C/14CO2 amount in the atmosphere (and its trend), utilizing calculation of a 14C activity concentration. A parameter connected only with a 14C quantity in the volume or mass unit of air is not influenced by a fossil carbon amount. Such a “robust” parameter can be
influenced only by processes connected with 14C emissions/depositions. 相似文献