30 research outputs found
2-Benzyliminomethyl-4-chlorophenol
The title compound, C14H12ClNO, is a Schiff base derived from the condensation of equimolar quantities of 5-chlorosalicylaldehyde and 1-benzylamine. The molecule has a trans configuration with respect to the imine C=N double bond. The N atom is involved in an intramolecular O—H⋯N hydrogen bond
Bis[μ-2-(benzyliminomethyl)-4-chlorophenolato]bis[chloridocopper(II)]
The title complex, [Cu2(C14H11ClNO)2Cl2], has a centrosymmetric dinuclear structure where two symmetry-related copper(II) metal centres are bridged by the O atoms of two phenoxy groups. Each copper(II) centre displays a distorted tetrahedral coordination provided by one N atom and two O atoms from two Schiff base ligands and by one Cl atom. The Cu⋯Cu separation is 3.0702 (9) Å
A Novel Fluorogenic Coumarin Substrate for Monitoring Acid Phosphatase Activity at Low pH Environment
This article described the synthesis and application of 6-chloro-8-fluoro-4-methylumbelliferone phosphate (CF-MUP) in analyzing acid phosphatase activity. Compared to the existing MUP, the new coumarin phosphate, CF-MUP, demonstrateed much higher sensitivity and was more robust for detecting the activity of acid phosphatase than the classic substrate 4-methylumbelliferone phosphate (MUP). The product of enzyme reaction, 6-chloro-8-fluoro-4-methylumbelliferone (CF-MU) possesses strong fluorescence at ~450 nm with low pKa (4.7), high fluorescence quantum yield and pH independence in the physiological pH range. This new fluorescence dye, CF-MU, is a convenient tool for assays with buffer pH between 4.5 and 8
Temperature-Dependent Photoluminescence Property of Self-Assembly ZnO Nanowires via Chemical Vapor Deposition Combined with Hydrothermal Pretreatment
Vertically aligned ZnO nanowires with high aspect ratio were prepared by chemical vapor deposition on Si substrate, which had been catalyzed by the polar plane in [0001] direction of ZnO nanorods prepared by the hydrothermal method. Morphology and structure characterizations showed that the as-grown nanowires had the single-crystal hexagonal wurtzite structure with a [0001] growth direction. Energy Dispersive X-ray (EDX) measurement indicated the as-grown ZnO nanowires had a good deal of oxygen vacancies owing to the high operation temperature. Temperature-dependent photoluminescence measurement revealed that the peak of near-band-edge emission shifted from 380 to 387 nm with the increase of temperature from 150 to 300 K. The high intensity of the green peak at 525 nm highlighted the potential application in visible light emitting diodes
Temperature-Dependent Photoluminescence Property of Self-Assembly ZnO Nanowires via Chemical Vapor Deposition Combined with Hydrothermal Pretreatment
Vertically aligned ZnO nanowires with high aspect ratio were prepared by chemical vapor deposition on Si substrate, which had been catalyzed by the polar plane in [0001] direction of ZnO nanorods prepared by the hydrothermal method. Morphology and structure characterizations showed that the as-grown nanowires had the single-crystal hexagonal wurtzite structure with a [0001] growth direction. Energy Dispersive X-ray (EDX) measurement indicated the as-grown ZnO nanowires had a good deal of oxygen vacancies owing to the high operation temperature. Temperature-dependent photoluminescence measurement revealed that the peak of near-band-edge emission shifted from 380 to 387 nm with the increase of temperature from 150 to 300 K. The high intensity of the green peak at 525 nm highlighted the potential application in visible light emitting diodes
Bis(4-chloro-2-formylphenolato)nickel(II)
The asymmetric unit of the title compound, [Ni(C7H4ClO2)2], contains one half-molecule. The NiII ion, lying on an inversion centre, is four-coordinated by O atoms of 5-chlorosalicylaldehydate ligands in a square-planar geometry
Influence of in-situ stress distribution on selection of fracturing fluid backflow technology
The distribution of in-situ stress has significant influence on fracture propagation direction so as to affect the selection of the fluid backflow technology. The influences on the longitudinal cracks in fracture propagation direction, caused by vertical stress distribution of the interlayer-oil layer, was firstly analyzed. Then, the settling rule of proppant within the fractures during the flowing back process was analyzed. Meanwhile, the bottomhole pressure curves under different nozzle diameters after shut-in were obtained by the volume balance principle. Therefore, the facture closure time and the maximum proppant settling distance were determined. Finally, combined with the field data, fracturing fluid backflow process, which considered the influence of in-situ stress, was optimized. Calculation shows that the location of oil layer in the in-situ stress zone and the proppant settling distance have close relations with the selection of fracturing fluid backflow technology. Hence, the optimization of fracturing fluid backflow technology requires consideration of the key factors above