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61.
62.
We present a method to implement the quantum partial search of the database separated into any number of blocks with qudits,D-level quantum systems.Compared with the partial search using qubits,our method needs fewer iteration steps and uses the carriers of the information more economically.To illustrate how to realize the idea with concrete physical systems,we propose a scheme to carry out a twelve-dimensional partial search of the database partitioned into three blocks with superconducting quantum interference devices(SQUIDs)in cavity QED.Through the appropriate modulation of the amplitudes of the microwave pulses,the scheme can overcome the non-identity of the cavity–SQUID coupling strengths due to the parameter variations resulting from the fabrication processes.Numerical simulation under the influence of the cavity and SQUID decays shows that the scheme could be achieved efficiently within current state-of-the-art technology.  相似文献   
63.
A novel 5-aminoisophthalate compound, [Mn(C8H5NO4)(H2O]n(2nH2O 1, has been synthesized by the hydrothermal assembly of 5-aminoisophthalic acid with manganese acetate. Ele- mental analysis, X-ray crystal structure analyses, IR spectra, FT-Raman and ESR were carried out for the structural determination and characterization of the title compound. Compound 1 crystallizes in triclinic, space group Pī with a = 7.7562(2), b = 8.6121(3), c = 8.7107(2)(A), α = 85.411(2), β = 76.030(2), γ = 66.510(2)o, V = 517.76(3)(A)3, MnC8H11NO7, Mr = 288.12, Z = 2, Dc = 1.848 g/cm3, μ = 1.300 mm-1, F(000) = 294, R = 0.0381 and wR = 0.1043 for 1652 observed reflections (I > 2σ(I)).  相似文献   
64.
Nanocrystalline Co(x)Ni(y)Cu(100-x-y) particles were synthesized by the reduction of metal acetates in a mixture of polyol and Tween 80. Inductively coupled plasma (ICP) analysis revealed that the actual wt% of Co, Ni, and Cu in these nanoparticles was nearly the same as in the starting solutions. The structures of the particles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) spectroscopy, and vibrating sample magnetometry (VSM). The results of XRD and VSM confirmed that there was no metastable alloying in the particles. The particles were composites, consisting of nanoscale crystallites of face-centered cubic (fcc) Cu, face-centered cubic (fcc) Ni, and face-centered cubic (fcc) Co. During preparation the nucleation of Cu occurred first; then small Cu nuclei acted as cores for the precipitation of Co and Ni. The particles showed an increase in saturation magnetization (M(s)) as the concentration of Co or Ni in the particles was increased. The changes of both M(s) and coercivity of the particles with increasing annealing temperatures were studied. The coercivity of the particles was very high; it could reach as high as 489 Oe for Co34.3Ni31.2Cu34.5) .  相似文献   
65.
It is well known that γ-Fe_2O_3 is a very active and selective catalyst for okidative dehydrogenation ofbutene to butadiene. It is hard, however, to distingulsh between ferrite spinels and therefore to identify its existence in ferrite-ferric oxide catalysts using XRD. On the IR spectra γ-Fe_2O_3 has characteristic bands in the range of 600~800 cm~(-1), which do not exist for α-Fe_2O_3, Fe3O4, ZnFe_2O_4 and MgFe_2O_4. But these bands are too weak to deterAnne for the small amount of γ-Fe_2O_3, e g. less than 30% (mass fraction), in catalysts.
Usually using second derivative IR spectra can increase the analytical sensitivity substantially. The mechanical mixtures of γ-Fe_2O_3 and MgFe_2O_4 in different ratio were prepared and their second derivative IR spectra were taken. It was found that the bands 730 and 695 cm~(-1) were characteristic of γ-Fe_2O_3 and their intensities increased with the content of γ-Fe_2O_3 in the mixtures. A staight line with R=0.994 can describe the relation between γ-Fe_2O_3 content and the peak area of band 695 cm~(-1). The lowest detectable content of γ-Fe_2O_3 is about 1% (mass fraction). The existence of γ-Fe_2O_3 in the used B-02 comercial catalyst was identified by this method.  相似文献   
66.
Two novel Cd(II)-citrate complexes were obtained with different metal/ligand ratios through hydrothermal method. Their structures were determined by single-crystal X-ray diffraction analysis. Although their topological structures are both 2-D layer network assemblies, both central Cd(II) ions and Hcit3− ligands display completely different coordination modes. In polymeric complex 1, Hcit3− serves as a μ10-bridged and central Cd(II) ions adopt 6- and 8-coordinated configurations. In contrast, a μ9-bridged and 6- and 7-coordinated environments between Cd(II) and Hcit3− are established in the polymeric complex 2. Two Complexes remain stable up to approximately 300 °C. The complex 1 exhibits strong fluorescent emission band at 450 nm (λ=346 nm) as well as complex 2 exhibits strong fluorescent emission band at 430 (λ=346 nm).  相似文献   
67.
Synthesis and Crystal Structure of [La(BTC)(H2O)6]n   总被引:1,自引:0,他引:1  
1 INTRODUCTION desired topologies owing to their rich coordination modes[8~12] and we have been exploring the chemi- The assembly of metal-organic infinite frame- stry of coordination polymers constructed by tran- works via coordination of metal ions with multifunc- sition metals and benzoic multicarboxylic acids[13~16]. tional organic ligands is a field of increasing inte- In addition, lanthanide ions have high affinity for rest[1~4]. A rational designed and predictable coor- hard donor a…  相似文献   
68.
Since the trinuclear molybdenum cluster compound Mo3S4(DTP)3(μ-DTP)(L) (DTP=diethyldithiophosphate, L=loosely-coordinated ligand) was reported[1],a large number of monomeric trinuclear molybdenum derivatives have been synthesized from it by its diverse substitution reactions[2]. This reaction provides a useful route to design cluster complexes with specific functions. By the reaction with α, ω-dicarboxylates, we successfully synthesized the first oligomer containing two incomplete cubane-type[Mo3S4] cores formulated as[Mo3S4(DTP)3(DMF)]22-μ-OOC(CH2)3COO-μ-η2]) whose molecule structure is as follows:  相似文献   
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