Described herein is a Pd-catalyzed haloallylation of aromatic ynol ethers and allyl chlorides, allowing facile access to (1E)-α-chloroenol ethers in a highly regio- and stereoselective manner. The synthetic utility of this method is demonstrated well by the synthesis of the stereodefined multisubstituted enol ethers and α-allylated carbonyl compounds. 相似文献
Quantum information processing has become increasingly attractive in the past few decades due to its extraordinary performance. However, few results of quantum signal and its related manipulations based on quantum computation have emerged in recent years. The paper proposes a generalized floating-point representation of quantum signals (GFPRQS), which is improved by represent an arbitrary quantum signal with p + q qubits. In a floating-point representation, although every number is approximated using three registers, this format allows to represent a much larger range of values with a given number of qubits than a fixed-pointing representation. Based on GFPRQS representation, we first present the quantum circuits to accomplish basic signal modules (i.e., multiplyby 2 module, halving module, comparator module, swap module, etc,). And then, we design a composite module (i.e., sort module). At the end of the paper, to indicate the usability of the model GFPRQS an example involving the mean filtering and its quantum circuit is given.
We report on a microfluidic platform that integrates a winding microdroplet chip and a surface-enhanced Raman scattering (SERS) detection system for trace determination of crystal violet (CV). Colloidal silver was applied to generate SERS. Compared to the continuous flow microfluidic system, the microdroplet based detection described here effectively eliminates any memory effects. Effects of flow pattern, droplet size, surfactant, and position of detection were optimized. Under optimal conditions, there is a linear correlation between signal and the concentration of CV in the 10 nM to 800 nM range, with a correlation coefficient (R2) of 0.9967. The limit of detection in water is 3.6 nM.
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A winding microdroplet chip based on SERS detection was developed for trace levels of crystal violet. Under optimal conditions,there is a good linear correlation in the 10 nM to 800 nM range with LOD is 3.6 nM. 相似文献
In this work, the responses of a Y-cut langasite crystal resonator (LCR) in liquid phases were investigated by an impedance analysis method. The resonant frequency (fS) of the LCR decreases with increasing mass loading on the active surface of the resonator. The LCR can be operated at the resonant frequency that is down to about 60% of the fundamental frequency (f0) under foreign mass loading. The frequency-mass coefficient of the Y-cut LCR is theoretically derived to be −1.282 × 10−6, which is supported by the experimental results. The resonant frequency of the LCR decreases linearly while its motional resistance (Rm) increases linearly with increasing (ρη)1/2, where η and ρ are the viscosity and density of the liquid phase, respectively. The slopes of the plots of fS versus (ρη)1/2 and Rm versus (ρη)1/2 are related to the region of (ρη)1/2 because of the influence of surface roughness of the LCR. The changes in viscodensity of a room temperature ionic liquid (RTIL), 1-octyl-3-methylimidazolium bromide ([C8MIM][Br]), were investigated in acetone vapor adsorption and ascending temperature processes by the LCR. The adsorption of acetone into [C8MIM][Br] causes a significantly drop in viscosity of the [C8MIM][Br] film, which induces an increase in fS and a decrease in Rm for the RTIL modified LCR. When the thickness of [C8MIM][Br] film is less than the decay distance of the thickness-shear wave, a mass effect model is observed in the early adsorption process. Based on the responses of the LCR, the viscodensity of the [C8MIM][Br] film as well as the adsorbed amounts of acetone into film were monitored in real time during the adsorption or desorption processes. 相似文献
High-performance and low-cost electrochemical capacitors (ECs) are essential for large-scale applications in energy storage. In this work, the specific capacitance of active carbon (AC) electrode was significantly improved through the combination of introducing functional groups on the surface of AC and adding redox-active molecules (K3Fe(CN)6) into 2?M KOH aqueous electrolytes. The surface-oxygen functionalized AC (FAC) was synthesized using HNO3 echoed as the electrode and 2?M KOH with 0.1?M K3Fe(CN)6 as the electrolyte. The surface functional groups of the AC not only contribute to the pseudocapacitance but also increase the active sites of the electrode/electrolyte interface, which enhances the electrochemical activity of the Fe(CN)63?/Fe(CN)64? redox pair, thus leading to high capacitance. In the redox electrolyte, the specific capacitance was much higher in 229.17?F?g?1 (1?A?g?1) achieved for those FAC than in raw AC (only 147.06?F?g?1). Similarly, the FAC electrode suggested high energy density and extended cycling stability in the KOH?+?K3Fe(CN)6 electrolyte. 相似文献
A novel method for fabricating a nanoarray electrode combining the template technique with the self-assembled approach was developed. The glassy carbon electrode was modified with the Au nanoarray using micropores of aluminum anodic film as template. Then, the Au nanoarray electrode was self-assembled with L-cysteine (L-Cys) and gold colloid, respectively. In order to evaluate the electrochemical characteristics of L-Cys–Au colloid self-assembled nanoarray electrode, was chosen as molecule probe and cyclic voltammetry was used. In addition, the functional nanoarray electrode was applied to measuring dopamine (DA). The resulting L-Cys–Au colloid self-assembled nanoarray electrode demonstrated that the linear calibration range extended over three orders of magnitude of DA concentrations (1.0 × 10−9–1.0 × 10−6 mol/L) and the detection limit was 5.0 × 10−10 mol/L. 相似文献