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21.
We investigate quantum echo control and Bell state swapping for two atomic qubits (TAQs) coupling to two-mode vacuum cavity field (TMVCF) environment via two-photon resonance. We discuss the effect of initial entanglement factor ?? and relative coupling strength R=g1/g2 on quantum state fidelity of TAQs, and analyze the relation between three kinds of quantum entanglement(C(ρa),C(ρf),S(ρa)) and quantum state fidelity, then reveal physical essence of quantum echo of TAQs. It is shown that in the identical coupling case R=1, periodic quantum echo of TAQs with π cycle is always produced, and the value of fidelity can be controlled by choosing appropriate ?? and atom-filed interaction time. In the non-identical coupling case R≠1, quantum echoes with periods of π, 2π and 4π can be formed respectively by adjusting R. The characteristics of quantum echo results from the non-Markovianity of TMVCF environment, and then we propose Bell state swapping scheme between TAQs and two-mode cavity field.  相似文献   
22.
A microwave electrically tunable photonic crystal based on a periodically width-modulated slot transmission line with a ferroelectric film is investigated for the first time. The dispersion and transmission characteristics of electromagnetic waves propagating in such a structure are calculated. The electric control over photonic crystal characteristics is simulated.  相似文献   
23.
安镜如  王东进 《分析化学》1994,22(11):1158-1162
本进行了N-(β-羧丙酰基)异鲁米诺的电致化学发光行为的研究。采用正矩形液脉冲电压,在KOH-KCl-H2O2-(pH11.6)介质中,N-(β-羧丙酰基)异鲁米诺测定的线性范围为4.0×10^-10 ̄7.0×10^-8mol/L,检出限为2.0×10^-10mol/L。本对此体系的电致化学发光机理进行了探讨。  相似文献   
24.
Abstract

In continuation of the search for new compounds from the terrestrial fungus Aspergillus sp., one new butyrolactone, 3-hydroxymethyl-butyrolactone II (1) was isolated. The chemical structure of 1 was confirmed by extensive 1D and 2D NMR and HR-ESI mass data analysis, and by comparison with literature data. The absolute configuration was also determined by ECD calculations.  相似文献   
25.
    
Precise separation and localization of microdroplets are fundamental for various fields, such as high-throughput screening, combinatorial chemistry, and the recognition of complex analytes. We have developed a droplet self-splitting strategy to divide an impacting droplet into predictable microdroplets and deposit them at preset spots for simultaneous multidetection. No matter exchange was observed between these microdroplets, so they could be manipulated independently. Droplet self-splitting was attributed to anisotropic liquid recoiling on the patterned adhesive surface, as influenced by the droplet Weber number and the width of the low-adhesive stripe. A quantitative criterion was also developed to judge the droplet self-splitting capability. The precise separation and distribution of microdroplets enabled simultaneous arrayed reactions and multiple analyte detection using one droplet of sample.  相似文献   
26.
    
Acetylcholinesterase (AChE) is an extremely critical hydrolase tightly associated with neurological diseases. Currently, developing specific substrates for imaging AChE activity still remains a great challenge due to the interference from butyrylcholinesterase (BChE) and carboxylesterase (CE). Herein, we propose an approach to designing specific substrates for AChE detection by combining dimethylcarbamate choline with a self-immolative scaffold. The representative P10 can effectively eliminate the interference from CE and BChE. The high specificity of P10 has been proved via imaging AChE activity in cells. Moreover, P10 can also be used to successfully map AChE activity in different regions of a normal mouse brain, which may provide important data for AChE evaluation in clinical studies. Such a rational and effective approach can also provide a solid basis for designing probes with different properties to study AChE in biosystems and another way to design specific substrates for other enzymes.

In this work, a new approach was developed for designing the representative P10 with high selectivity and sensitivity for imaging AChE activity in the cells and normal mouse brain.  相似文献   
27.
本文报道ICP-MS直接测定高纯(5N~6N)氧化镱中稀土和非稀土杂质的新方法.对ICP-MS测定中的光谱干扰和基体效应进行了详细考察,结果表明:用镓作内标,可有效地补偿因氧化镱引起的基体效应.方法的检出限在0.0X-0.Xng/mL范围;相对标准偏差(RSD)(n=7)<10%.已应用于高纯氧化镱的工艺流程及其产品分析.  相似文献   
28.
Ma  Lijiao  Xu  Ye  Zu  Yunfei  Liao  Qing  Xu  Bowei  An  Cunbin  Zhang  Shaoqing  Hou  Jianhui 《中国科学:化学(英文版)》2020,63(1):21-27
In order to meet the requirements for making organic solar cells(OSCs) through solution printing techniques, great efforts have been devoted into developing high performance OSCs with relatively thicker active layers. In this work, a thick-film(300 nm)ternary OSC with a power conversion efficiency of 14.3% is fabricated by introducing phenyl-C_(61)-butyric-acid-methyl ester(PC_(61)BM) into a PBDB-T-2Cl:BTP-4 F host blend. The addition of PC_(61)BM is found to be helpful for improving the hole and electron mobilities, and thus facilitates charge transport as well as suppresses charge recombination in the active layers, leading to the improved efficiencies of OSCs with relatively thicker active layers. Our results demonstrate the feasibility of employing fullerene derivative PC_(61)BM to construct a high-efficiency thick-film ternary device, which would promote the development of thick layer ternary OSCs to fulfill the requirements of future roll to roll production.  相似文献   
29.
Polymerization-induced self-assembly(PISA) is an efficient and versatile method to afford polymeric nano-objects with polymorphic morphologies. Compared to dispersion PISA syntheses based on soluble monomers, the vast majority of emulsion PISA formulations using insoluble monomers leads to kinetically-trapped spheres. Herein, we present aqueous emulsion PISA formulations generating worms and vesicles besides spheres. Two monomers with different butyl groups, n-butyl(n BHMA) and tert-butyl(t BHMA) α-hydroxymethyl acrylate, and thus possessing different water solubilities were synthesized via Baylis-Hillman reaction. Photoinitiated aqueous emulsion polymerizations of n BHMA and t BHMA employing poly(ethylene glycol) macromolecular chain transfer agents(macro-CTAs, PEG45-CTA, and PEG113-CTA) at 40 °C were systematically investigated to evaluate the effect of monomer structure and solubility on the morphology of the generated block copolymer nano-objects. Higher order morphologies including worms and vesicles were readily accessed for t BHMA, which has a higher water solubility than that of n BHMA. This study proves that plasticization of the core-forming block by water plays a key role in enhancing chain mobility required for morphological transition in emulsion PISA.  相似文献   
30.
This study aimed to improve the stability of nanofibrillated cellulose (NFC) in an electrolyte containing system, which was achieved by the grafting of 2-acrylamido-2-methylpropane sulfonic acid (AMPS) via the ceric ammonium nitrate-induced polymerization process. The results indicated that upon grafting the salt resistance and thermal stability of NFC were significantly improved. Moreover, the stability of the modified NFC increased with the AMPS loading. Compared to the control (the original NFC), the poly-AMPS/NFC (357.5 mg/g AMPS) exhibited much improved stability in a 400 mmol/L NaCl solution, and its viscosity was 350 mPa s. The thermogravimetric analysis results showed that the initial decomposition temperature of the modified NFC increased from 265 to 330 °C. Transmission electron microscopy (TEM) observations showed that the main morphologic features of NFC were not altered, suggesting that the grafting reaction occurred on the fiber surface. The modified NFC can have promising industrial applications, such as oil recovery.  相似文献   
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