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21.
Basic Theory in Construction of Boolean Functions with Maximum Possible Annihilator Immunity 总被引:9,自引:0,他引:9
So far there is no systematic attempt to construct Boolean functions with maximum annihilator immunity. In this paper we present
a construction keeping in mind the basic theory of annihilator immunity. This construction provides functions with the maximum
possible annihilator immunity and the weight, nonlinearity and algebraic degree of the functions can be properly calculated
under certain cases. The basic construction is that of symmetric Boolean functions and applying linear transformation on the
input variables of these functions, one can get a large class of non-symmetric functions too. Moreover, we also study several
other modifications on the basic symmetric functions to identify interesting non-symmetric functions with maximum annihilator
immunity. In the process we also present an algorithm to compute the Walsh spectra of a symmetric Boolean function with O(n2) time and O(n) space complexity.
We use the term “Annihilator Immunity” instead of “Algebraic Immunity” referred in the recent papers [3–5, 9, 18, 19]. Please
see Remark 1 for the details of this notational change 相似文献
22.
B.R. Chakraborty A.G. Shard M.K. Dalai G. Sehgal 《Surface and interface analysis : SIA》2014,46(1):36-41
Depth profiling of an organic reference sample consisting of Irganox 3114 layers of 3 nm thickness at depths of 51.5, 104.5, 207.6 and 310.7 nm inside a 412 nm thick Irganox 1010 matrix evaporated on a Si substrate has been studied using the conventional Cs+ and O2+ as sputter ion beams and Bi+ as the primary ion for analysis in a dual beam time‐of‐flight secondary ion mass spectrometer. The work is an extension of the Versailles Project on Advanced Materials and Standards project on depth profiling of organic multilayer materials. Cs+ ions were used at energies of 500 eV, 1.0 keV and 2.0 keV and the O2+ ions were used at energies of 500 eV and 1.0 keV. All four Irganox 3114 layers were identified clearly in the depth profile using low mass secondary ions. The depth profile data were fitted to the empirical expression of Dowsett function and these fits are reported along with the full width at half maxima to represent the useful resolution for all the four delta layers detected. The data show that, of the conditions used in these experiments, an energy of 500 eV for both Cs+ beam and O2+ beam provides the most useful depth profiles. The sputter yield volume per ion calculated from the slope of depth versus ion dose matches well with earlier reported data. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
23.
Dalai Jin ;Ruirui Liu ;Xiaochu Ding ;Longcheng Wang ;Lina Wang ;Linhai Yue 《Particuology》2014,(6):54-58
A facile solid-phase conversion route is proposed to fabricate a micro-framework of α-MnO_2 with a nanofibrous structure and high porosity.The fabrication is achieved by a three-step process using a preformed manganese tartrate with a rectangular framework as the precursor followed by thermal annealing and hydrothermal oxidation to form the final nanofibrous structure.Evolution of the phase and the morphology are characterized by FESEM,XRD,TG-DTA,and TEM measurements.The electrochemically active material α-MnO_2 exhibits both attractive stability of the Coulombic efficiency after long-term cyclic charging/discharging and acceptable specific capacitance. 相似文献
24.
Biochar was evaluated as a precursor of activated carbon. This product was produced by chemical activation using potassium hydroxide. The effects of operating conditions of activation process, such as temperature, activating agent to biochar mass ratio, and nitrogen flow rate, on the textural and chemical properties of the product were investigated. Activated carbon produced by this method has internal surface area at least 50 times than that of the precursor and is highly microporous, which is also confirmed by scanning electron microscopy analysis. Fourier-transform infrared spectroscopy analysis showed development of aromatization in the structure of activated carbon. X-ray diffraction data indicated the formation of small, two-dimensional graphite-like structure at high temperatures. Thermogravimetric study showed that when potassium hydroxide to biochar mass ratio was more than one, the weight loss decreased. 相似文献
25.
Chiral allenes are readily accessed in a single pot operation in the reaction of terminal alkynes, aldehydes, chiral secondary amines, and zinc halides in good yields (up to 77% yield) and excellent enantioselectivities (up to 99% ee) in toluene at 120 °C. The reaction proceeds through initial formation of chiral propargylamine intermediates with creation of a new stereogenic center and subsequent chirality transfer via an intramolecular hydride shift to produce chiral allenes with high enantiomeric purities. 相似文献
26.
Weiliang Shi Limin Si Linhai Yue Lina Wang Dalai Jin 《Crystal Research and Technology》2011,46(7):701-704
In this paper, a template free method has been employed to fabricate porous ZnO. Brick shaped precursor was first synthesized by a mild hydrothermal process. Accompanied with the decomposition of the precursor during the subsequent annealing treatment, porous ZnO with the inherited morphology of the precursor was obtained. The as‐prepared products were characterized by X‐ray diffraction (XRD) and scanning electron microscopy (SEM). It exhibited that the porous hierarchical frame consists of nano‐sheets with wurtzite‐type. The size of the pores as well as the size of the particles varied with the annealing temperature. Mechanism speculation showed that the crystal‐aggregation in the growth process of the precursor is the key to the establishment of pore structure. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
27.
Swapan Kumar Jana Madhusudan Bera Horst Puschmann Sudipta Dalai 《Journal of fluorescence》2014,24(4):1245-1251
The recognition ability of N-Furfurylsalicylaldimine (HL) toward various cations (Pb2+, Hg2+, Ba2+, Cd2+, Ag+, Zn2+, Cu2+, Ni2+, Co2+, K+, Sr2+, and Na+) has been studied by UV–Vis and fluorescence spectroscopy. The compound showed highly selective fluorescence signaling behaviour for Zn2+ ions in methanol-water medium based on CHEF process and is capable of distinguishing Zn2+ from Cd2+ ion. From single crystal X-ray analysis it is revealed that a Zn2+ ion binds two ligand molecules through imine nitrogen and phenolate oxygen atom. Figure
N-Furfurylsalicylaldimine as a selective sensing of Zn2+ ion through CHEF process. The x-ray structure of the receptor-Zn(II) complex shows 2:1 stochiometry 相似文献
28.
Chitosan‐g‐polycaprolactone copolymers (CPCs) with desired composition proportions were synthesized by carefully controlling the weight ratio of polycaprolactone side chains changing approximately between 45 and 48 wt% so that the obtained CPCs could be further processed via different processing techniques. Aqueous acetic acid solutions and dimethyl sulfoxide were respectively employed as solvents to fabricate CPCs into fibrous mesh scaffolds that had nearly similar parameters characterized by the average porosity and pore‐size of scaffolds as well as the average diameter of filaments under optimal processing conditions. The swelling index, surface group analysis, antibacterial activity and tensile mechanical properties of these mesh scaffolds were investigated in several ways, and the scaffolds showed quite different properties due to the different processing methods employed, although the same type of CPC was used. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
29.
Hydrothermal synthesis of Zn2SnO4 nanorods in the diameter regime of sub-5 nm and their properties 总被引:1,自引:0,他引:1
Single crystalline Zn(2)SnO(4) (ZTO) nanorods 2-4 nm in diameter and around 20 nm in length were successfully synthesized by a simple hydrothermal process with use of hydrazine hydrate as an alkaline mineralizer instead of NaOH or NH(3).H(2)O. By analyzing the UV-vis diffuse reflectance spectrum, the optical band gap (E(g)) of the nanorods was found to be 3.87 eV, which indicates a blue shift of 0.27 eV from that of bulk ZTO (3.6 eV). In situ high-temperature X-ray diffraction was employed to study the thermal expansion coefficient and the variation of lattice parameter with temperature of the product. Furthermore, we discussed the chemical mechanism and key factors to the hydrothermal formation of the sub-5 nm ZTO nanorods. 相似文献
30.
Novel nut-like zinc oxide crystal has been prepared by a low temperature hydrothermal method with the presence of Cu2+ ion. It seemed that the ultrasonic pretreatment was the key factor during the preparation process. SEM observations revealed that the as-prepared ZnO crystal exhibited nut shape showing well-defined crystallographic facets. The cross-section of the ZnO crystal was hexagonal of about 800 nm–1 μm in diameter, and the aspect ratio was a little smaller than 1:1. The room temperature photoluminescence behavior of the nut-like zinc oxide crystal was much stronger than the reference samples. 相似文献