2,057 research outputs found
2-(Dibutylamino)-3-(4-fluorophenyl)-5,6,7,8-tetrahydro-7-methyl-6,8-diphenylpyridine[3′,4′:2,3]thieno[5,4-d]pyrimidin-4(3H)-one
In the crystal structure of the title compound, C36H39FN4OS, the two fused rings of the thienopyrimidine system are coplanar. The 4-fluorophenyl ring is twisted with respect to the heterocyclic pyrimidinone ring by 67.21 (14)°. The piperidine ring shows a half-chair conformation. One of the n-butyl chains is disordered equally over two sites. The crystal packing is stabilized by C—H⋯O hydrogen bonds
Nodeless energy gaps of single-crystalline Ba0.68K0.32Fe2As2 as seen via 75As NMR
We report As nuclear magnetic resonance studies on a very clean
hole-doped single-crystal BaKFeAs ( K). The spin-lattice relaxation rate shows an exponential
decrease below down to ,
which indicates a fully opened energy gap. From the ratio , where and denote the crystal directions, we find that the
antiferromagnetic spin fluctuation is anisotropic in the spin space above
. The anisotropy decreases below and disappears at . We argue that the anisotropy stems from spin-orbit coupling
whose effect vanishes when spin-singlet electron pairs form with a nodeless
gap.Comment: 10 pages, 6 figure
Tetrakis[μ3-4-nitro-N-(5-phenyl-1,3,4-oxadiazol-2-yl)benzamidato]tetrakis[methanolsodium(I)]
In the title compound, [Na4(C15H9N4O4)4(CH3OH)4], the N3O3 environment around the Na+ ion is distorted octahedral. In the unit cell, four Na+ ions are bridged by four Schiff base anions, leading to a tetranuclear complex with -4 symmetry. O—H⋯N hydrogen bonds between the methanol molecule and the Schiff base anion stabilize the structural set-up
Fault Modeling and Testing for Analog Circuits in Complex Space Based on Supply Current and Output Voltage
This paper deals with the modeling of fault for analog circuits. A two-dimensional (2D) fault model is first proposed based on collaborative analysis of supply current and output voltage. This model is a family of circle loci on the complex plane, and it simplifies greatly the algorithms for test point selection and potential fault simulations, which are primary difficulties in fault diagnosis of analog circuits. Furthermore, in order to reduce the difficulty of fault location, an improved fault model in three-dimensional (3D) complex space is proposed, which achieves a far better fault detection ratio (FDR) against measurement error and parametric tolerance. To address the problem of fault masking in both 2D and 3D fault models, this paper proposes an effective design for testability (DFT) method. By adding redundant bypassing-components in the circuit under test (CUT), this method achieves excellent fault isolation ratio (FIR) in ambiguity group isolation. The efficacy of the proposed model and testing method is validated through experimental results provided in this paper
Antibacterial Mechanism of the Ehyl Acetate Extracts From Naked Oat Again Bacillus Subtilis
The antibacterial mechanism of the ethyl acetate extracts from naked oat against Bacillus subtilis were studied in this paper based on assays such as cell wall alkaline phosphatase (AKP), permeability and integrity of cell membrane as well as electron microscopy observations. The results showed that the ethyl acetate extracts had significant effects on AKP, permeability and integrity of cell membrane. We concluded that the mechanism of action of the ethyl acetate extracts against B. subtilis might be described as:Acting on cell wall and membrane, resulting in disruption, cell lysis, and the leakage of intracellular constituents according to the results of AKP, the leakage of electrolytes, the losses of contents (proteins, reducing sugars and 260 nm absorbing materials) assays and electron microscopy observations. Overall, the results clearly indicated that the ethyl acetate extracts from naked oat was potential to control the contamination of foods caused by bacterial disease
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