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991.
The preparation and crystal structure of complex Co(Hsae)2·2H2O (1, H2sae = N-salicylidene-2-iminoethanol) are reported. X- ray analysis revealed that every six Co(Hsae)2 forms a cyclic chip and every 12 water forms a novel gear-like cluster. Acting as building blocks, the gear-like water cluster and complex chip are connected in A-B fashion and extend into one-dimensional supramolecular chain. Hydrogen bond is the primary bridging force in the formation of supramolecular framework.  相似文献   
992.
A series of transition metal phosphides, including MoP, WP, CoP, Co2P, and Ni2P, were synthesized from their oxidic precursors by means of hydrogen plasma reduction under mild conditions. The effects of reduction conditions, such as metal to phosphorus molar ratio, power input, and reduction time, on the synthesis of metal phosphides were investigated. The products were identified by means of XRD characterization. It is indicated that metal phosphides were readily synthesized stoichiometrically from their oxides in hydrogen plasma under mild conditions.  相似文献   
993.
Bond distances, vibrational frequencies, electron affinities, ionization potentials, dissociation energies and dipole moments of the title molecules in neutral, positively and negatively charged ions were studied by use of density functional method. Ground electronic state was assigned for each molecule. The bonding patterns were analyzed and compared with both the available data and across the series. It was found that besides ionic component, covalent bonds are formed between the metal s, d and f orbitals and oxygen p orbitals. Contrary to the well known lanthanide contraction, the bond distance is not regular from LaO to LuO for both neutral and charged molecules. An obvious population at 5d orbital was observed through the lanthanide series. 4f electrons also participate the chemical bonding for CeO to NdO and TbO to TmO. For EuO, GdO, YbO and LuO, 4f electrons tend to be localized. The spin multiplicity is regular for neutral and charged molecules. The spin multiplicity of the charged molecules can be obtained by −1 (or +1 for TbO+, DyO+, YbO and YbO+) compared with the corresponding neutral molecules.  相似文献   
994.
995.
996.
Five complexes [Co3(Hpmad)6]·(4‐sb)2·(CH3COO)2·(H2O)2 ( 1 ), [Co3(Hpmad)6]·(3‐sb)2·(CH3COO)2·(H2O)0.5 ( 2 ), [Co(Hpmad)2(4‐sb)]n ( 3 ), [Co(Hpmad)2(3‐sb)]n ( 4 ) and {[Co(Hpmad)(SO4)(H2O)2]·H2O}n ( 5 ) [Hpmad is 2‐pyrimidineamidoxime, H2(4‐sb) is 4‐sulfobenzoic acid and H2(3‐sb) is 3‐sulfobenzoic acid], were prepared at room temperature. Complexes 1 – 5 were characterized by elemental analyses, single crystal X‐ray diffractions, powder X‐ray diffractions, infrared spectra, thermogravimetric analyses, fluorescence spectra and magnetic susceptibility measurements. Complexes 1 and 2 possess the linear trinuclear Co2+ structures. Complexes 3 and 4 exhibit similar one‐dimensional (1D) chains. Complex 5 comprises the 1D helical chain. The change of anion in cobalt salt from CH3COO? to Cl? to SO42? leads to the structural evolution from the linear trinuclear Co2+ structure to the 1D chain to the 1D helical chain. Complexes 1 – 5 exhibit the Hpmad‐based emissions. The magnetic properties of 1–5 were also investigated.  相似文献   
997.
Gao  Xia  Zhao  Tianbo  Luo  Guan  Zheng  Baohui  Huang  Hui  Chai  Yuqiao  Ma  Rui  Han  Xue 《Journal of Thermal Analysis and Calorimetry》2019,135(4):2125-2136

Leakage and incompatibility of paraffin wax (PW) in hydroxyl-terminated polybutadiene (HTPB) binders is a major obstacle to its application in polymer-bonded explosives (PBX). In order to solve this issue, we designed a microencapsulated PW (MePW)/PW/HTPB composite in this paper. Melamine–formaldehyde-shelled MePW (MF MePW)/PW/HTPB composites with different contents of MePW and PW were prepared by cast molding method. The chemical composition, crystallinity and microstructure of MePW/PW/HTPB composites were analyzed with Fourier transformed infrared spectroscopy, X-ray diffraction and scanning electron microscope, respectively. The results showed that PW and MF MePW have been uniformly dispersed in HTPB without any chemical interaction. Moreover, differential scanning calorimeter analysis, thermal gravimetric analyzer, thermal cycling test, leaking test, tensile and compressive test were used to investigate the thermal and mechanical properties of these composites. The composites have high latent heat and good thermal reliability. The thermal stability, tensile and compressive strength of MePW/PW/HTPB composites were dramatically increased with the increasing mass fraction of MePW. The introduction of MePW can obviously prevent the leakage of PW in both HTPB binders and PBX. Consequently, it is anticipated that MePW can be used in the next-generation of paraffin-based high-temperature PBX systems.

  相似文献   
998.
Utilizing a general joint remote state preparation (JRSP) model, we investigate the JRSP of an arbitrary two-qubit quantum state in noisy environments. Two important decoherence noise models, the amplitude-damping noise and the phase-damping noise, have been considered in our paper. Our investigation of the noisy environment mainly focuses on the process of distributing the channel state. We use fidelity to describe how close the output state with the prepared state are, and how much information has been lost in the transmission. Interestingly, studies show that, if the initial state is successfully prepared, the fidelities in these two cases will only depend on the amplitude parameter of the initial state and the decoherence noisy rate, but have nothing to do with the phase information. Finally, we make some discussions for these two cases to show that in which noisy environment more information will be lost.  相似文献   
999.
Exploration of α,α-dibromo-β-dicarbonyl compounds as novel organic oxidants for the mild Cu(I)-catalyzed Glaser-type homo-coupling reaction has been achieved, which provides an alternatively efficient pathway for the construction of 1,3-conjugated structures. In addition, the mechanism of this reaction was investigated.  相似文献   
1000.
Superlattice materials offer new opportunities to modify optical and electrical properties of recently emerging 2D materials. The insertion of tetraethylbenzidine (EtDAB) into interlamination of the established 2D PbI2 semiconductor through a mild solution method yielded the first lead iodide superlattice, EtDAB?4PbI2 (EtDAB=tetraethylbenzidine), with radical and non‐radical forms. The non‐radical form has a non‐ionic structure that differs from the common ionic structures for inorganic–organic hybrid lead halides. The radical form shows five orders of magnitude greater conductance and broader photoconductive response range (UV/Vis → UV/Vis‐IR), than pure PbI2 and the non‐radical form of the superlattice.  相似文献   
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