(2E,6E)-2,6-Difurfurylidenecyclo­hexa­none

The complete mol­ecule of the title compound, C16H14O3, is generated by crystallographic mirror symmetry, with two C atoms and one O atom lying on the mirror plane. The mol­ecule adopts an E configuration about the C=C bond and the dihedral angle between the furan rings is 16.1 (2)°

Study of Mid-Infrared Optical Properties of ZnS Thin Films by Spectroscopic Ellipsometry

In order to obtain the mid-infrared optical properties of ZnS thin films, ZnS films with different thickness were prepared on K9 glass substrate by electronic beam evaporation. They were denoted by Aã€Bã€C . The optical properties of thin films were studied by Spectroscopic Ellipsometry. The measured date of film A ã€Bã€C were fitted by Brendel oscillator, and based on ZnS film properties and the film forming characteristic of the ZnS film, building the model“substrate(K9 glass)/EMA(50% K9 glass and 50% ZnS)/ZnS/rough surface layer(50% ZnS and 50% air)/airâ€. The optical constants curve and thickness of ZnS thin film were got. The results shown that the evaluation function MSE is small when Brendel model is used in data fitting. Within the wavelength range of 3000nm ~ 12500nm, the ZnS thin films refractive index and extinction coefficient are reduced with increasing wavelength. The Extinction coefficient tends to zero near the long wavelengh. The thickness of ZnS measured value was closest to the theoretical value. The results have certain reference value to measurement and preparation of high quality ZnS thin film

Effect of nematic order on the low-energy spin fluctuations in detwinned BaFe1.935_{1.935}Ni0.065_{0.065}As2_2

The origin of nematic order remains one of the major debates in iron-based superconductors. In theories based on spin nematicity, one major prediction is that the spin-spin correlation length at (0,$\pi$) should decrease with decreasing temperature below the structural transition temperature $T_s$. Here we report inelastic neutron scattering studies on the low-energy spin fluctuations in BaFe$_{1.935}$Ni$_{0.065}$As$_2$ under uniaxial pressure. Both intensity and spin-spin correlation start to show anisotropic behavior at high temperature, while the reduction of the spin-spin correlation length at (0,$\pi$) happens just below $T_s$, suggesting strong effect of nematic order on low-energy spin fluctuations. Our results favor the idea that treats the spin degree of freedom as the driving force of the electronic nematic order.Comment: 5 pages, 4 figure

Review of variable speed drive technology in beam pumping units for energy-saving

Beam pumping units have been widely used in oilfields worldwide due to its simple structure, strong field adaptability, and convenient maintenance. Different energy-saving technologies have also been broadly applied in various beam pumping units. Among these energy-saving methods, the variable speed drive is one of the most acceptable techniques in the oil and gas industry. In this paper, the energy-saving technology of variable speed drives is discussed in detail for beam pumping units pointing out existing difficulties and current research status in kinematics. Three application examples of a variable speed drive in Daqing oilfield, the largest oilfield in China, is shown

In situ growth of SnO2 on graphene nanosheets as advanced anode materials for rechargeable lithium batteries

Graphene with a single layer of carbon atoms densely packed in a honeycomb crystal lattice is one of attractive materials for the intercalation of lithium ion, but it has low volumetric capacity owing to low tap density. We report a method for in situ growth of SnO2 on graphene nanosheets (SGN) as anode materials for rechargeable lithium batteries. The results indicated that the SnO2 nanoparticles with size in the range of 5-10 nm and a polycrystalline structure are homogeneously supported on graphene nanosheets. The charge and discharge capacities of SGN attained to 1559.7 and 779.7 mAh/g in the first cycle at a current density of 300 mA/g. The specific discharge capacities remained at 620 mAh⋅g-1 in the 200th cycle. The SGN exhibits a superior Listorage performance with good cycle life and high capacity

A novel bath lily-like graphene sheet-wrapped nano-Si composite as a high performance anode material for Li-ion batteries

A novel bath lily-like graphene sheet-wrapped nano-Si composite synthesized via a simple spray drying process exhibits a high reversible capacity of 1525 mAh g(-1) and superior cycling stability, which could be attributed to a synergistic effect between highly conductive graphene sheets and active nanoparticles in the open nano/micro-structure