Effects of the laser surface treatment on the mechanical properties of CuZr-based bulk metallic glasses

Surfaces of three types of CuZr-based bulk metallic glasses (BMGs) were modified by laser surface treatment (LST), and the influence of the treatment on structure and mechanical properties of these alloys was investigated. The phase structure of as-cast and laser-treated samples was characterized by XRD and the morphology of the alloys after fracture was examined by SEM. The compressive plasticity of treated Cu47.5Zr47.5Al5 and Cu46.5Zr47.5Al5Co1 BMGs can be improved from 0.5% to 2.0% and from 1.2% to 5.7% respectively compared with the as-cast ones, while (Cu0.55Zr0.40Al0.05)99Er1 BMG shows insignificant change of plasticity. The improvement in plasticity is attributed to induced crystallization of B2 CuZr phase in the treated surface zone of selected metallic glasses.     

Tensor force effect on proton shell structure in neutron-rich Ca isotopes

In the framework of the Skyrme-Hartree-Fock approach with 36 sets of the TI J parameterizations,the tensor force effect on the evolution of the single-proton states in the calcium isotopes is systematically investigated.It is shown that the single-proton states with higher angular momenta are influenced significantly by the tensor force and the trend in the evolution of somesingle-particle energy differences with the mass number of the isotopes depends sensitively on a parameter βT associated with the intensity of the tensor force.To understand this phenomenon,we analyze the spin-orbit potentials and the radial wave functions of relevant single-proton orbits in detail.In addition,it is found that some TI J interactions could cause the 2s1/21d3/2 energy level inversion in 48Ca.     

Application of wavelet transform in-ray spectra analysis

The frequency distribution of different ingredients in-ray spectra,e.g.,photo-peak,fluctuations of counts and Compton region,is separately analyzed.After wavelet transform of-ray spectra,the wavelet coefficients of a photo-peak increase with transforming scales and these coefficients show direct proportion with intensity of peak at determinate scale.A novel algorithm based on wavelet transform is proposed and studied.The results indicate that most of the photo-peaks in multi-spectra can be determined accurately,the-rays energy and intensity of the peak can also be determined.This method has the prospect of being applied in on-line multi-spectra analysis in such fields as radioprotection and nuclear safety monitoring.     

ISOVALEROYL OXOKADSURANE,A NOVEL DIBENZOCYCLOOCTADIENE LIGNAN POSSESSING A SPIROBENZOPURANOID SKELETON

Isovaleroyl oxokadsurane, a novel dibenzocyclooctadiene lignan pos-sessing a spirobenzofuranoid skeleton was isolated from the stems of Kadsura coccinea.Its structure and relative configuration were determined by X-ray diffraction analysis.     

CuNaY分子筛的制备及其催化甲醇氧化羰基化

采用多种铜盐溶液与NaY分子筛离子交换制备了CuNaY催化剂,通过加入氨水提高溶液pH值以及高温活化,显著提高了该催化剂对甲醇氧化羰基化合成碳酸二甲酯的反应活性。不同的铜盐水溶液交换制备的CuNaY催化剂催化活性不同,添加氨水将溶液pH值调节为11后,离子交换制备的CuNaY催化剂的催化活性和DMC选择性明显升高且趋于一致。经元素分析、XRD、XPS和H₂-TPR表征可知,加入氨水可促进Cu²⁺离子交换的进行,提高CuNaY催化剂中Cu的交换量,催化剂中约75%的Cu²⁺定位于分子筛的超笼中。     

A Germanate Compound Constructed from Dissymmetric Ge7 Chains and Metal Complexes

Abstract. A novel germanate compound, |[Ni(dien)₂]₃(H₂O)₃|[Ge₇O₁₃F₅]₂(designated JU‐85, dien = diethylenetriamine), was solvothermally synthesized. The structure of JU‐85 was determined by single‐crystal X‐ray diffraction and further characterized by powder X‐ray diffraction, inductively coupled plasma, infrared spectroscopy, elemental analysis, and thermogravimetric analysis. JU‐85 has dissymmetric chains constructed from diagonally linked Ge₇ building units and various Ni(dien)₂²⁺ complexes formed in situ during the synthesis. Compared with its structural analogue, FJ‐6, JU‐85 contains less complex cations and different host‐guest assembly. Besides the diagonal linkage in JU‐85, other dissymmetric linkages of Ge₇ building units were enumerated, which could be used as the stereogenic centers for the design of novel chiral germanate compounds.     

Synthesis and Properties of Novel Luminescent Compounds Containing Triphenylamine and Bipyridine Units

Blue luminescent compounds T1-T4 containing triphenylamine donors,bipyridine acceptors and olefinic linkers were synthesized and characterized by 1H NMR,13C NMR and high resolution mass spectrometry(HR...     

A DOUBLE-TEMPERATURE-GRADIENT TECHNIQUE FOR THE GROWTH OF PURE C60 SINGLE CRYSTALS FROM THE VAPOR PHASE

Pure C₆₀ single crystals were grown by a sublimation-condensation method in an evacuated dosed quartz tube situated in a double-temperature-gradient furnace. Large C₆₀ single crystals, up to a size of 0.6 mm×1.0 mm×2.0 mm with quite smooth and shiny faces, were obtained. X-ray diffraction, electron diffraction and X-ray morphology were carried out and showed that the quality of large C₆₀ single crystals grown by the double-temperature-gradient technique is excellent. In this paper the experimental results of the growth of large C₆₀ single crystals are reported and the morphological and structural characterizations are discussed in detail.