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1.
Phys Rev Lett ; 129(16): 160602, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36306769

RESUMO

Operator spreading, often characterized by out-of-time-order correlators (OTOCs), is one of the central concepts in quantum many-body physics. However, measuring OTOCs is experimentally challenging due to the requirement of reversing the time evolution of systems. Here we apply Floquet engineering to investigate operator spreading in a superconducting 10-qubit chain. Floquet engineering provides an effective way to tune the coupling strength between nearby qubits, which is used to demonstrate quantum walks with tunable couplings, reversed time evolution, and the measurement of OTOCs. A clear light-cone-like operator propagation is observed in the system with multiple excitations, and has a nearly equal velocity as the single-particle quantum walk. For the butterfly operator that is nonlocal (local) under the Jordan-Wigner transformation, the OTOCs show distinct behaviors with (without) a signature of information scrambling in the near integrable system.

2.
Dent Mater ; 38(11): 1689-1702, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36115699

RESUMO

OBJECTIVE: A low-shrinkage-stress resin-based cement with antibacterial properties could be beneficial to create a cement with lower stress at the tooth-restoration interface, which could help to enhance the longevity of the fixed dental restoration by reducing microleakage and recurrent caries. To date, there has been no report on the development of a low-shrinkage-stress and bio-interactive cement. Therefore, the objectives of this study were to develop a novel low-shrinkage-stress resin-based cement containing dimethylaminohexadecyl methacrylate (DMAHDM) and investigate the mechanical and antibacterial properties for the first time. METHODS: The monomers urethane dimethacrylate (UDMA) and triethylene glycol divinylbenzyl ether (TEG-DVBE) were combined and denoted as UV resin. Three cements were fabricated: (1) UV+ 0%DMAHDM (experimental control); (2) UV+ 3%DMAHDM, (3) UV+ %5DMAHDM. RelyX Ultimate cement was used as commercial control. Mechanical properties and Streptococcus mutans (S. mutans) biofilms growth on cement were evaluated. RESULTS: The novel bio-interactive cement demonstrated excellent antibacterial and mechanical properties. Compared to commercial and experimental controls, adding DMAHDM into the UV cement significantly reduced colony forming unit (CFU) counts by approximately 7 orders of magnitude, metabolic activities from 0.29 ± 0.03 A540/cm2 to 0.01 ± 0.01 A540/cm2, and lactic acid production from 22.3 ± 0.74 mmol/L to 1.2 ± 0.27 mmol/L (n = 6) (p < 0.05). The low-shrinkage-stress cement demonstrated a high degree of conversion of around 70 %, while reducing the shrinkage stress by approximately 60%, compared to a commercial control (p < 0.05). CONCLUSIONS: The new antibacterial low-shrinkage-stress resin-based cement provides strong antibacterial action and maintains excellent mechanical properties with reduced polymerization shrinkage stress. CLINICAL SIGNIFICANCE: A low-shrinkage-stress resin-based cement containing DMAHDM was developed with potent antibacterial effects and promising mechanical properties. This cement may potentially enhance the longevity of fixed dental restoration such as a dental crown, inlay, onlay, and veneers through its excellent mechanical properties, low shrinkage stress, and strong antibacterial properties.


Assuntos
Metacrilatos , Cimentos de Resina , Antibacterianos/farmacologia , Biofilmes , Cimentos Dentários , Materiais Dentários , Éteres , Ácido Láctico/metabolismo , Metacrilatos/farmacologia , Metilaminas
3.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 51(9): 558-61, 2016 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-27596347

RESUMO

OBJECTIVE: To develop a novel protein-repellent orthodontic adhesive by incorporating 2-methacryloyloxyethyl phosphorylcholine(MPC). METHODS: MPC was incorporated into a commercially available orthodontic adhesive(Fuji ORTHO) at 0% (control), 1.5%, 3.0%, and 5.0% by mass. Enamel shear bond strength(SBS) was determined. Protein adsorption onto specimens was determined by a micro bicinchoninic acid method. A dental plaque microcosm biofilm model with human saliva as inoculum was used to investigate biofilm viability. RESULTS: The SBS was not reduced in the group(3.0% MPC), compared to the control group. The amount of protein adsorption in the group(3.0% MPC) was (0.46±0.06) µg/cm(2) and (4.57 ± 0.42) µg/cm(2) in the control group. Lactic acid production of biofilms in the group(3.0% MPC) was (7.12±1.03) mmol/L and (12.16±1.24) mmol/L in the control group. CONCLUSIONS: MPC based orthodontic adhesive greatly reduced the protein adsorption and bacterial adhesion, without compromising enamel shear bond strength.


Assuntos
Cimentos Dentários/química , Adsorção , Antibacterianos , Aderência Bacteriana , Biofilmes , Colagem Dentária , Esmalte Dentário , Placa Dentária , Ácido Láctico , Metacrilatos , Braquetes Ortodônticos , Fosforilcolina/análogos & derivados , Proteínas , Cimentos de Resina , Saliva , Resistência ao Cisalhamento
4.
Nat Commun ; 7: 11018, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27009972

RESUMO

Stimulated Raman adiabatic passage offers significant advantages for coherent population transfer between uncoupled or weakly coupled states and has the potential of realizing efficient quantum gate, qubit entanglement and quantum information transfer. Here we report on the realization of the process in the superconducting Xmon and phase qutrits--two ladder-type three-level systems in which the ground state population is coherently transferred to the second excited state via the dark state subspace. We demonstrate that the population transfer efficiency is no less than 96% and 67% for the two devices, which agree well with the numerical simulation of the master equation. Population transfer via stimulated Raman adiabatic passage is significantly more robust against variations of the experimental parameters compared with that via the conventional resonant π pulse method. Our work opens up a new venue for exploring the process for quantum information processing using the superconducting artificial atoms.

5.
J Hazard Mater ; 170(2-3): 883-7, 2009 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-19501959

RESUMO

An aqueous C.I. Acid Red 2 solution was decolorized by electrolysis using iron as anode. The decolorization mechanism was investigated through experimental observations on the electrochemical behavior of C.I. Acid Red 2 on Pt rotating disk electrode, UV-visible spectra of the solution and IR spectra of the coagulated mixtures. It is found that the decolorization efficiency is high, over 98.0% after 40 min, and this high decolorization efficiency can be ascribed to the synergistic effect of electrocoagulation and electrooxidation. The electrocoagulation results from the electrogenerated iron hydroxide and the electrooxidation results from electrogenerated ferric ions. The results obtained from IR spectra shows that the decolorization of C.I. Acid Red 2 by electrooxidation is due to the partial or complete cleavage of C-N bonds in C.I. Acid Red 2.


Assuntos
Compostos Azo/química , Corantes/química , Algoritmos , Cor , Eletroquímica , Eletrodos , Eletrólise , Oxirredução , Oxigênio/análise , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
6.
J Pharm Sci ; 98(4): 1487-98, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18752294

RESUMO

This article presents a new method for on-line monitoring of pharmaceutical production process, especially the powder blending process. The new method consists of two parts: extracting features from the Near Infrared (NIR) spectroscopy signals and recognizing patterns from the features. Features are extracted from spectra by using Partial Least Squares method (PLS). The pattern recognition is done by using Hidden Markov Model (HMM). A series of experiments are conducted to evaluate the effectiveness of this new method. In the experiments, wheat powder and corn powder are blended together at a set concentration. The proposed method can effectively detect the blending uniformity (the success rate is 99.6%). In comparison to the conventional Moving Block of Standard Deviation (MBSD), the proposed method has a number of advantages, including higher reliability, higher robustness and more transparent decision making. It can be used for effective on-line monitoring of pharmaceutical production processes.


Assuntos
Modelos Químicos , Preparações Farmacêuticas/química , Espectroscopia de Luz Próxima ao Infravermelho , Tecnologia Farmacêutica/métodos , Tomada de Decisões , Cadeias de Markov , Preparações Farmacêuticas/normas , Pós , Controle de Qualidade , Tecnologia Farmacêutica/normas
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