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1.
Montgomery Multiplication in GF(2k) 总被引:8,自引:0,他引:8
We show that the multiplication operation c=a · b · r-1 in the field GF(2k can be implemented significantly faster in software than the standard multiplication, where r is a special fixed element of the field. This operation is the finite field analogue of the Montgomery multiplication for modular multiplication of integers. We give the bit-level and word-level algorithms for computing the product, perform a thorough performance analysis, and compare the algorithm to the standard multiplication algorithm in GF(2k. The Montgomery multiplication can be used to obtain fast software implementations of the discrete exponentiation operation, and is particularly suitable for cryptographic applications where k is large. 相似文献
2.
State-to-state vibrational energy relaxation (VER) rates of the OH-stretch fundamental to select vibrational modes of liquid methanol are presented. The rates are calculated via a modified, fluctuating Landau-Teller (FLT) theory approach, which allow for dynamical vibrational energy level shifts. These rates are then compared to previously published results from Gulmen and Sibert [J. Phys. Chem. A 2004, 108, 2389] for the traditional Landau-Teller (LT) method as well as results calculated through time-dependent perturbation theory (TD), which naturally allow for the fluctuation. For the first time, this method is applied to a polyatomic molecular system, and the FLT theory greatly reduces the discrepancy between the LT and TD results or, at a minimum, is comparable to the LT approach with very little additional computational cost. 相似文献
3.
Özlem Usluer Christian Kästner Mamatimin Abbas Christoph Ulbricht Vera Cimrova Andreas Wild Eckhard Birckner Nalan Tekin Niyazi Serdar Sariciftci Harald Hoppe Silke Rathgeber Daniel A. M. Egbe 《Journal of polymer science. Part A, Polymer chemistry》2012,50(16):3425-3436
This article reports on the synthesis, characterization, and properties of various anthracene‐containing poly (p‐phenylene‐ethynylene)‐alt‐poly(p‐phenylene‐vinylene) (PPE‐PPV) polymers (AnE‐PVs) bearing statistical distributions of various side chains. Primarily, the ratio of linear octyloxy and branched 2‐ethylhexyloxy side chains at the poly(p‐phenylene vinylene) (PPV) parts was varied, leading to the polymers stat, stat1, and stat2. Furthermore, polymers also containing asymmetric substituted PPV and poly(p‐phenylene ethynylene) units (bearing methoxy and 2‐ethylhexyloxy side chains) were prepared yielding stat3, stat4, and stat5. These materials exhibit a broad variation in their photovoltaic properties. It is once more shown that side chains and their distribution can crucially affect the photovoltaic device performance. The introduction of units with asymmetric substitution into these systems seems to be harmful for their utilization in photovoltaic applications. Organic field‐effect transistors were fabricated to investigate hole mobilities in these new materials. Large variance was observed, falling in the range of almost two orders of magnitude, indicating rather different π–π stacking behavior of the polymer backbones owing to side‐chain modifications. Moreover, a selection of the new polymeric systems was investigated regarding their potential for light‐emitting diode (LED) applications. Polymer LEDs using the polymers AnE‐PVstat, ‐stat3, ‐stat4, and ‐stat5, as the active layer showed turn‐on voltage of ~2 V and exhibited red light emission. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
4.
Yasemin Budama-Kilinc Rabia Cakir-Koc Serda Kecel-Gunduz Tolga Zorlu Yagmur Kokcu Bilge Bicak Zeynep Karavelioglu Aysen E. Ozel 《Journal of fluorescence》2018,28(5):1127-1142
Papain is a protease enzyme with therapeutic properties that are very valuable for medical applications. Poly(ε-caprolactone) (PCL) is an ideal polymeric carrier for controlled drug delivery systems due to its low biodegradability and its high biocompatibility. In this study, the three-dimensional structure and action mechanism of papain were investigated by in vitro and in silico experiments using molecular dynamics (MD) and molecular docking methods to elucidate biological functions. The results showed that the size of papain-loaded PCL nanoparticles (NPs) and the polydispersity index (PDI) of the NPs were 242.9 nm and 0.074, respectively. The encapsulation efficiency and loading efficiency were 80.4 and 27.2%, respectively. Human embryonic kidney cells (HEK-293) were used for determining the cytotoxicity of papain-loaded PCL and PCL nanoparticles. The in vitro cell culture showed that nanoparticles are not toxic at low concentrations, while toxicity slightly increases at high concentrations. In silico studies, which were carried out with MD simulations and ADME analysis showed that the strong hydrogen bonds between the ligand and the papain provide stability and indicate the regions in which the interactions occur. 相似文献
5.
6.
Ahmet Karadağ Ali Aydin Şaban Tekin Hüseyin Akbaş Süreyya Dede 《Journal of Coordination Chemistry》2019,72(5-7):860-878
The synthesis of three bimetallic cyanido complexes with edbea [2,2′-(ethylenedioxy)bis(ethylamine)] ligand is reported. [NiII(μ-edbea)2{Au(μ-CN)2}2]n (1), [{CuII(edbea)}2{Au(μ-CN)2}4]n (2) and [CdII(edbea)2][Au(CN)2]2·H2O (3) were fully characterized by elemental, infrared, XRD (3), ESI-MS and thermal analysis. The DNA/BSA binding properties of these complexes were evaluated by spectrophotometric titration, fluorometric ethidium bromide kinetics, and DNA electrophoresis studies and their partially minor groove binding mode between the base pairs of DNA and electrostatic interaction between the amino acid residues of BSA were explained. The complexes were tested for their pharmacological properties. These molecules had excellent in vitro antiproliferative activity and also exhibited a strong tumor inhibiting effect against HT29, HeLa, C6 and Vero cell lines. These complexes had metastatic features as they are able to reduce cell migration activity and suppress tumor growth in vitro. Analysis of the DNA topoisomerase I relaxing activity indicates that the complexes do not inhibit topoisomerase I which regulates the topological states of the DNA double helix during DNA processing reactions. The TUNEL and DNA laddering assay results indicated that these compounds may destroy cell maintenance by triggering apoptosis. Immunohistochemistry staining analysis demonstrated that these complexes significantly decreased the expression of Bcl-2 in HeLa and HT29 cells while increasing the expression of P53 levels. Overall, the potent antiproliferative activity, low cytotoxic effect, good solubility, and micro molar range dosage observed for these complexes emphasizes their potential as anticancer drug candidates. 相似文献
7.
8.
In this study, Fe3O4@TiO2 nanoparticles were synthesized as a new Positron Emission Tomography/Magnetic Resonance Imaging (PET/MRI) hybrid imaging agent and radiolabeled with 89Zr. In addition, Fe3O4 nanoparticles were synthesized and radiolabeled with 89Zr. Df-Bz-NCS was used as bifunctional ligand. The nanoconjugates were characterized with transmission electron microscopy, scanning electron microscopy, and dynamic light scattering. Radiolabeling yields were 100%. Breast and prostate cancer cell affinities and cytotoxicity were determined using in vitro cell culture assays. The results demonstrated that Fe3O4@TiO2 nanoparticles are promising for PET/MR imaging. Finally, unlike Fe3O4 nanoparticles, Fe3O4@TiO2 nanoparticles showed a fluorescence spectrum at an excitation wavelength of 250 nm and an emission wavelength of 314 nm. Therefore, in addition to bearing the magnetic properties of Fe3O4 nanoparticles, Fe3O4@TiO2 nanoparticles display fluorescence emission. This provides them with photodynamic therapy potential. Therefore multimodal treatment was performed with the combination of PDT and RT by using human prostate cancer cell line (PC3). The development of 89Zr-Df-Bz-NCS-Fe3O4@TiO2 nanoparticles as a new multifunctional PET/MRI agent with photodynamic therapy and hyperthermia therapeutic ability would be very useful. 相似文献
9.
Murat Ates Nesimi Uludag Tolga Karazehir Fatih Arican 《Journal of Solid State Electrochemistry》2013,17(9):2417-2427
In this work, (3,6-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-9-(4-vinylbenzyl)-9H-carbazole) (EDOTVBCz) comonomer was chemically synthesized and characterized by Fourier transform infrared (FTIR), proton nuclear magnetic resonance, and carbon nuclear magnetic resonance spectroscopy. EDOTVBCz was electrocoated on glassy carbon electrode (GCE) in various initial molar concentrations ([EDOTVBCz]0?=?1.0, 1.5, 2.0, and 3.0) in 0.1 M lithium perchlorate (LiClO4)/acetonitrile (CH3CN). P(EDOTVBCz)/GCE was characterized by cyclic voltammetry, FTIR reflectance-attenuated total reflection spectroscopy, scanning electron microscopy–energy dispersive X-ray analysis, atomic force microscopy, and electrochemical impedance spectroscopy (EIS). EIS was used to determine the capacitive behaviors of modified GCE via Nyquist, Bode magnitude, Bode phase, and admittance plots. The highest low-frequency capacitance value was obtained as C LF?=?~2.35 mF cm?2 for [EDOTVBCz]0?=?3.0 mM. Double-layer capacitance of the polymer/electrolyte system was calculated as C dl?=?~2.78 mF cm?2 for [EDOTVBCz]0?=?1.0 and 3.0 mM. The maximum phase angle was obtained as θ?=?~76.7o for [EDOTVBCz]0?=?1.0, 1.5, 2.0, and 3.0 mM at the frequency of 20.6 Hz. AC impedance spectra of P(EDOTVBCz)/LiClO4/CH3CN was obtained by performing electrical equivalent circuit model of R(Q(R(CR))) with linear Kramers–Kronig test. Figure
SEM-EDX analysis of P(EDOTVBCz)/CFME EDX point analysis inset: SEM point analysis, [EDOTVBCz]0?=?3 mM. Chronoamperometric method of constant potential at 1.6 V, 300 s in 0.1 M LiClO4/CH3CN 相似文献
10.
Ayfer Yurt Kilcar Fazilet Zumrut Biber Muftuler Huseyin Enginar Volkan Tekin Emin Ilker Medine Perihan Unak 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):563-573
Recently, the development of novel brain imaging agents has aroused much interest thanks to limited number of brain cancer or diseases diagnosis agents. It is aimed to synthesize a novel brain imaging agent including a promise for further studies on AD diagnosis potential and investigate its bioaffinity with biodistribution studies on healthy Balb/c mice. A novel radiolabeled agent was synthesized and characterized. Quality control of 99mTc-BH was performed utilizing solvent extraction and chromatographic (Radio TLC and Radio HPLC) methods. Bioaffinity of the 99mTc-BH was investigated on male Balb/c mice at various time points (5, 30, 60, 120 min post-injection). Paper electrophoresis showed that 99mTc-BH has a neutral structure. Radiochemical purity of 99mTc-BH was over 95 % with appropriate stability for imaging period. Selected brain regions have uptakes over 4 % ID/g following intravenous injection. Hippocampus has uptake approximately 10 % ID/g. 99mTc-BH has shown brain uptake, so it may prove to be valuable for brain imaging as a novel technetium-labeled agent. Further investigations with AD animal model are our on going effort to show that this agent has AD diagnosis potential. 相似文献