NONLINEAR DYNAMICS AND SYNCHRONIZATION OF TWO COUPLED PIPES CONVEYING PULSATING FLUID

In this paper, the nonlinear dynamical behavior of two coupled pipes conveying pulsating fluid is studied. The connection between the two pipes is considered as a distributed linear spring. Based on this consideration, the equations of motion of the coupled two-pipe system are obtained. The two coupled nonlinear partial differential equations, discretized using the fourth- order Galerkin method, are solved by a fourth-order Runge-Kutta integration algorithm. Results show that the connection stiffness has a significant effect on the dynamical behavior of the coupled system. It is found that for some parameter values the motion types of the two pipes might be synchronous.     

Investigating effect of pH values on CeSiW catalyst for the selective catalytic reduction of NO by NH3

Research on Chemical Intermediates - The effect of different pH values (8, 9, 10 and 11) on the catalytic activity over CeSiW catalysts was investigated for the selective catalytic reduction of NO...     

Validated liquid chromatography–tandem mass spectrometry method for quantification of ticagrelor and its active metabolite in human plasma

A rapid, simple and sensitive LC–MS/MS method was established and validated for simultaneous quantification of ticagrelor and its active metabolite AR‐C124910XX in human plasma. After plasma samples were deproteinized with acetonitrile, the post‐treatment samples were chromatographed on a Dikma C₁₈ column interfaced with a triple quadrupole tandem mass spectrometer. Electrospray negative ionization mode and multiple reaction monitoring were adopted to assay ticagrelor and AR‐C124910XX. Acetonitrile and 5 mΜ ammonium acetate was used as the mobile phase with a gradient elution at a flow rate of 0.5 mL/min. The method was linear in the range of 0.781–800 ng/mL for both ticagrelor and AR‐C124910XX with a correlation coefficient ≥0.994. The intra‐ and inter‐day precisions were within 12.61% in terms of relative standard deviation and the accuracy was within ±7.88% in terms of relative error. The LC–MS/MS method was fully validated for its sensitivity, selectivity, stability, matrix effect and recovery. This convenient and specific LC–MS/MS method was successfully applied to the pharmacokinetic study of ticagrelor and AR‐C124910XX in healthy volunteers after an oral dose of 90 mg ticagrelor.     

Deterministic Bidirectional Remote State Preparation of a- and Symmetric Quantum States with a Proper Quantum Channel

We present a new scheme for deterministically realizing the mutual interchange of quantum information between two distant parties via selected quantum states as the shared entangled resource. We first show the symmetric bidirectional remote state preparation (BRSP), where two single-qubit quantum states will be simultaneously exchanged in a deterministic manner provided that each of the users performs single-qubit von Neumann measurements with proper measurement bases as well as appropriate unitary operations, depending essentially on the outcomes of the prior measurements. Then we consider to extend the symmetric protocol to an asymmetric case, in which BRSP of a general single-qubit state and an arbitrary two-qubit state is investigated successfully. The necessary quantum operations and the employed quantum resources are feasible according to the present technology, resulting in that this protocol may be realizable in the realm of current physical experiment.     

Simultaneous Determination of Arsenic and Lead in Vegetable Oil by Atomic Fluorescence Spectrometry after Vortex-Assisted Extraction

Hydride generation atomic fluorescence spectrometry (HG-AFS) is used for the determination of hydride-forming elements due to its high sensitivity, simplicity, and low cost. A new HG-AFS method for the simultaneous determination of arsenic and lead in vegetable oil is reported. Vortex-assisted extraction with dilute nitric acid was used to isolate arsenic and lead from vegetable oil. The conditions influencing the fluorescence signal, including the carrier fluid, oxidizing agent, and reducing agent, were optimized. The interferences of coexisting ions were also evaluated. Under the optimized conditions, the limits of detection were 0.6 and 0.4?µg?kg^?1 for arsenic and lead. The recoveries were from 84.4 to 105% for both metals in vegetable oil. The optimized method was used for the determination of arsenic and lead in commercial vegetable oil. The analytical results by this approach were in good agreement with values obtained by inductively coupled plasma mass spectrometry with microwave digestion.     

Dynamic analysis and regulation of the flexible pipe conveying fluid with a hard-magnetic soft segment

Applied Mathematics and Mechanics - The recently developed hard-magnetic soft (HMS) materials can play a significant role in the actuation and control of medical devices, soft robots, flexible...     

Spatial variability and radiation assessment of the radionuclides in soils and sediments around a uranium tailings reservoir,south of China

Journal of Radioanalytical and Nuclear Chemistry - The concentrations of 238U, 226Ra, 232Th and 40K and gross α, β were measured in soils and sediments around a uranium tailings reservoir...     

Rapid Interception of CnF2n+1(O)SO. Radical with Copper-Based Carbene: A Novel Access to Perfluoroalkanesulfinate Ester

In this communication, an unprecedented interception of C_nF_2n+1(O)SO^. radical with a copper-based carbene has been established. Distinguished by wide substrate scopes and mild reaction conditions, this novel radical–carbene coupling reaction (RCC reaction) provides a fundamentally different and mechanistically interesting strategy for the synthesis of perfluoroalkanesulfinate esters.     

Cooperative Dehydrogenation of N‐Heterocycles Using a Carbon Nanotube–Rhodium Nanohybrid

Rhodium nanoparticles were anchored on carbon nanotubes and the resulting nanohybrid was studied as co‐catalyst, along with tert‐butylcatechol, for the dehydrogenation of various N‐heterocycles. The co‐catalytic system operates in high yields, under the mildest conditions reported so far, and can be applied to a wide variety of secondary amine‐containing scaffolds.