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11.
The title compound, [Cu2(C8H4O4)(C12H8N2)4](ClO4)2, was prepared from the hydro­thermal reaction of CuCl2, 1,4‐di­cyano­benzene, 1,10‐phenanthroline and water at 443 K. The compound is a dimer in which the cation lies about an inversion center. The terephthalate moiety acts as a bridging ligand and the phenanthrolines as terminal ligands. The unique Cu atom is coordinated by two O and four N atoms in a distorted octahedral geometry, with Cu—O distances of 1.955 (2) and 2.815 (2) Å, and Cu—N distances of 2.008 (2) to 2.216 (2) Å.  相似文献   
12.
Two-dimensional(2 D) Te nanosheets were successfully fabricated through the liquid-phase exfoliation(LPE) method. The nonlinear optical properties of 2 D Te nanosheets were studied by the open-aperture Z-scan technique. Furthermore, the continuous wave mode-locked Nd:YVO_4 laser was successfully realized by using 2 D Te as a saturable absorber(SA) for the first time, to the best of our knowledge. Ultrashort pulses as short as 5.8 ps were obtained at 1064.3 nm with an output power of 851 m W. This primary investigation indicates that the 2 D Te SA is a promising photonic device in the fields of ultrafast solid-state lasers.  相似文献   
13.
In this paper several new multiplicity results for asymptotically linear elliptic problem at resonance are obtained via Morse theory and minimax methods. Some new observations on the critical groups of a local linking-type critical point are used to deal with the resonance case at 0.  相似文献   
14.
In this paper we study a quasilinear elliptic system coupled by a Schrödinger equation with p-Laplacian operator and a Poisson equation. Some scaling transformation and ingenious methods are applied to produce the bounded Palais-Smale sequences and the existence of nontrivial solutions for the system is obtained by the mountain pass theorem.  相似文献   
15.
A new type of three-dimensional framework based on dodecanuclear Cd(II) macrocycles [[Cd2(dpa)(pya)]6(pya)6(dpe)3]n (1) (H2dpa = diphenic acid; Hpya = isonicotinic acid, dpe = 1,2-di(4-pyridyl)ethylene) was prepared by the hydrothermal reaction and in situ synthesis of pya from dpe precursor.  相似文献   
16.
PLS—分光光度法同时测定铜锌锰   总被引:6,自引:0,他引:6  
刘家宝  任英 《应用化学》1990,7(6):33-36
偏最小二乘法(PLS)是用于多组份混合体系同时测定的十分有效的统计学方法。本文将PLS法与光度分析相结合,以5Br-PADAP为显色体系同时计算测定了铜、锌、锰,并应用于铸铝样品的分析,都获得了较满意的结果。还用不相容因子(DF)自检分析结果的可靠性。  相似文献   
17.
Two L ‐phenylalanine derivatives with 5,8‐bis(2‐(carbazol‐3‐yl)vinyl)quinoxaline ( PCQ ) and 5,8‐bis[2‐(carbazol‐3‐yl)]‐2,3‐dimethylquinoxaline ( DCQ ) as fluorophores were synthesized, and their photophysical properties were measured and compared. The two compounds were found to gelate some organic solvents and self‐assemble into 1D nanofibers in gels. The wet gel of PCQ emitted a weak orange fluorescence, but the DCQ gel had a strong green one. This result can be due to the presence of two methyl groups and the nonplanar conformation of fluorophore in DCQ . The gel film of DCQ also showed significantly stronger fluorescence than that of PCQ . Thus, the wet gel and xerogel film of DCQ were selected to study their sensing properties to acids. The yellow wet gel of DCQ transformed into a brown sol upon the addition of 0.2 equiv trifluoroacetic acid (TFA), accompanied by emission quenching. The xerogel film of DCQ rapidly responded to volatile acids, such as TFA, HCl, and HOAc. The fluorescence of the xerogel film was gradually quenched with increased concentration of volatile acid vapors. The fibrous film exhibited low detection limits for volatile acid. The detection limits of the thin films for TFA, HCl, and HOAc reached 43, 122, and 950 ppb, respectively.  相似文献   
18.
Spinel ferrites are promising anode materials for lithium-ion batteries (LIBs) owing to their high theoretical specific capacities. However, their practical application is impeded by inherent low conductivity and severe volume expansion, which can be surpassed by increasing the surface-to-volume ratio of nanoparticles. Currently, most methods produce spinel ferrite nanoparticles with large size and severe aggregation, degrading their electrochemical performance. In this study, a low-temperature aminolytic route was designed to synthesize sub-10 nm CoFe2O4 nanoparticles with good dispersion through carefully exploiting the reaction of acetates and oleylamine. The performance of CoFe2O4 nanoparticles obtained by a traditional co-precipitation method was also investigated for comparison. This work demonstrates that CoFe2O4 nanoparticles synthesized by the aminolytic route are promising as anode materials for LIBs. Besides, this method can be extended to design other spinel ferrites for energy storage devices with superior performance by simply changing the starting material, such as MnFe2O4, MgFe2O4, ZnFe2O4, and so on.  相似文献   
19.
Single-crystalline Ni nanowires have been successfully fabricated with anodic aluminum oxide as template by electrodeposition. Structural characterization (X-ray diffraction, XRD, and high-resolution transmission electron microscopy, HRTEM) shows that the single-crystalline Ni nanowire has a preferred orientation along the [220] direction. The effects of electrochemical deposition conditions on the structure of Ni nanowires are systematically studied to investigate the growth mechanism. Possible reasons for the growth of the single-crystalline Ni nanowires were discussed on the basis of electrochemistry and thermodynamics. These single-crystalline Ni nanowires have exhibited excellent magnetic properties (large anisotropy, large coercivity, and high remanence). By a similar process, single-crystalline Co nanowires with hexagonal close-packed (hcp) structure were achieved, also having large anisotropy, large coercivity (1.8 kOe), and high remanence ratio (80.8%).  相似文献   
20.
In this paper we study the existence of nontrivial solutions of a class of asymptotically linear elliptic resonant problems at higher eigenvalues with the nonlinear term which may be unbounded by making use of the Morse theory for aC 2-function at both isolated critical point and infinity.  相似文献   
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