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271.
Shahram Minaei Oguzhan ÇiÇekoglu Hakan Kuntman Sait TÜrkÖz 《International Journal of Electronics》2013,100(8):915-922
Three new current-mode second-order filter configurations which employ one or two current controlled conveyors (CCCIIs) and three passive elements are presented. Each proposed filter can realize one of the bandpass, lowpass or highpass responses all at high impedance outputs. The proposed filters offer current-control of pole angular frequency ωo without disturbing the parameter ωo /Q. No component matching is required and all the passive and active sensitivities are low. PSPICE simulation results are given to confirm the theoretical analysis. 相似文献
272.
Gorazd Hribar Andrej Žnidaršič Marjan Bele Uroš Maver Simon Caserman Miran Gaberšček Vladka Gaberc-Porekar 《Journal of nanoparticle research》2011,13(7):3019-3032
The authors’ intention was to prepare nanometer-sized zinc-phosphate nanoparticles that would be capable of binding histidine-rich
TNF-α analogs onto their surface via a coordinative bond. Zinc-phosphate nanoparticles with a size of around 60 nm were prepared
by a wet precipitation method and characterized using SEM, EDX, XRD, and DLS. First, BSA was bound as a testing protein, afterward
two TNF-α analogs with decreased activity were bound to the described nanoparticles. The efficiency of binding and the existence
of coordinative bond were confirmed with SDS-PAGE analysis. During binding, particle storage, and release experiments, the
prepared TNF-α analogs retained their biological activity—hence the epitopes necessary for formation of antibodies stayed
intact. The particle size did not change within a period of 2 weeks. No significant agglomeration was observed, the particles
could be quickly dispersed in ultrasound. The present nanoparticles and the general approach of coordinative binding are widely
applicable for natural and engineered histidine-rich proteins. The nanoparticles bearing appropriate TNF-α analogs could also
be potentially used for active immunotherapy to tackle the chronic inflammatory diseases associated with pathogenically elevated
levels of TNF-α. 相似文献
273.
Borko D. Stoši? 《Physica A》2009,388(12):2373-2382
In this work an application of MCMC is proposed for unsupervised data classification, in conjunction with a novel pairwise objective function, which is shown to work well in situations where clusters to be identified have a strong overlap, and the centroid oriented methods (such as K-means) fail by construction. In particular, an exceptionally simple but difficult situation is addressed when cluster centroids coincide, and one can differentiate between the clusters only on the basis of their variance. Performance of the proposed approach is tested on synthetic and real datasets. 相似文献
274.
The lagrangian formulation of classical mechanics is applied to RLC circuits. The generalized power function is introduced and the reduced Lagrange equations are used in the analysis of the system. This new method seems to be more useful than the conventional Kirchhoff taws and Lagrange equations. This is illustrated by an example. 相似文献
275.
Vapor pressures of six pentanols, 2-methyl-1-butanol (CAS Registry Number 137-32-6), 2-methyl-2-butanol (CAS Registry Number 75-85-4), 3-methyl-1-butanol (CAS Registry Number 123-51-3), 3-methyl-2-butanol (CAS Registry Number 598-75-4), 2-pentanol (CAS Registry Number 6032-29-7) and 3-pentanol (CAS Registry Number 584-02-1), were measured by the precision ebulliometry over an approximate pressure range from 9 to 99 kPa. The absolute uncertainties in pressure and temperature are estimated to be less than or equal to 7 Pa and 0.02 K, respectively. The results are represented by the Antoine equation and compared with available literature data. 相似文献
276.
Matej Pavši? 《Physics letters. [Part B]》2011,703(5):614-619
We start from the Einstein-Hilbert action for the gravitational field in the presence of a “point particle” source, and cast the action into the corresponding phase space form. The dynamical variables of such a system satisfy the point particle mass shell constraint, the Hamilton and the momentum constraints of the canonical gravity. In the quantized theory, those constraints become operators that annihilate a state. A state can be represented by a wave functional Ψ that simultaneously satisfies the Klein-Gordon and the Wheeler-DeWitt-Schrödinger equation. The latter equation, besides the term due to gravity, also contains the Schrödinger like term, namely the derivative of Ψ with respect to time, that occurs because of the presence of the point particle. The particle?s time coordinate, X0, serves the role of time. Next, we generalize the system to p-branes, and find out that for a quantized spacetime filling brane there occurs an effective cosmological constant, proportional to the expectation value of the brane?s momentum, a degree of freedom that has two discrete values only, a positive and a negative one. This mechanism could be an explanation for the small cosmological constant that drives the accelerated expansion of the universe. 相似文献
277.
278.
Tahir Sofilić Delko Barišić Alenka Rastovčan Mioč Una Sofilić 《Journal of Radioanalytical and Nuclear Chemistry》2010,284(1):73-77
The objective of this study was to describe the radiochemical characteristics of electric arc furnace (EAF) slag from Croatian EAF black steel slags, generated from carbon steel production process in CMC Sisak d.o.o., and steel mill in Split in order to enhance the understanding of possibilities for their use in road construction. This article presents the results of radionuclide in electric arc furnace steel slag. The presence of natural isotopes 40K, 232Th (228Ra), 226Ra and 238U was established. The measured activity in slag natural isotopes lies within the Croatian legally permitted limits. 相似文献
279.
Yusuf Öztürk Asım Egemen Yılmaz Evrim Çolak Ekmel Özbay 《Photonics and Nanostructures》2012,10(4):624-631
Planar metamaterials, which have incident to normal plane excitation unlike SRR-type structures and that are easily fabricated in multilayer form, have received great interest in recent years. In this paper, one-dimensional and polarization independent circular fishnet metamaterials and their equivalent discontinuous slab-pair modeling for tuning resonance frequencies are introduced. After the numerical and experimental demonstration of the inclusions, the standard retrieval characterization methods and the correspondent/related backward-wave propagation observation are realized in order to check the physical explanation mentioned in the paper. In addition, a detailed phase analysis is performed in order to demonstrate the application of the suggested structure as a phase compensator. 相似文献
280.
We study the behavior of Milnor's µ-invariants of three- and four-component links with respect to the discriminant determined by $\Delta $ -moves of links. We introduce a new type of $\Delta $ -move, balanced $\Delta $ -moves, or, briefly, $B\Delta $ -moves. Since each four-component link is equivalent to a standard link under a sequence of balanced $\Delta $ -moves, $\Delta $ -moves that involve at most two components, and Reidemeister moves, we manage to define axiomatically µ-invariants of length $3$ for arbitrary semibounding links. 相似文献