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A new diarylethene compound with a triazole-linked rhodamine 6G unit attached to the imino group ( 1O ) was designed and synthesized. According to the test results, the solution color and fluorescence color of diarylethene can be modulated by lights and metal ions. The solution color could change from colorless to light purple when irradiated with UV light. When Cu 2+ was added to the diarylethene solution, the color of diarylethene solution became blue, the fluorescence color turned from dark to bright yellow. Although the solution color did not change by adding Fe 3+ , its fluorescence color varied from dark to yellow. Moreover, it was found that the complex ratio of the diarylethene to Cu 2+ was 1:1 and the binding stoichiometry of the diarylethene to Fe 3+ was also 1:1 based on the data of NMR, MS, and other experiments. Based on these findings, photochromic figure of the diarylethene with UV/Vis light, Cu 2+ and Fe 3+ was constructed. Furthermore, the logic circuit was designed by input signals (ultraviolet stimulus, visible light stimulus, Cu 2+ (or Fe 3+ ) and EDTA) and an output signal (fluorescent intensity at 566 nm (or 575 nm)). [ABSTRACT FROM AUTHOR]

Bone is a complex composite material with hierarchical structures and anisotropic mechanical properties. Bone also processes electromechanical properties, such as piezoelectricity and streaming potentials, which termed as stress generated potentials. Furthermore, the electrostrictive effect and flexoelectric effect can also affect electromechanical properties of the bone. In the present work, time responses of bending deflections of bone cantilever in an external electric field are measured experimentally to investigate bone's electromechanical behavior. It is found that, when subjected to a square waveform electric field, a bone cantilever specimen begins to bend and its deflection increases gradually to a peak value. Then, the deflection begins to decrease gradually during the period of constant voltage. To analyze the reasons of the bending response of bone, additional experiments were performed. Experimental results obtained show the following two features. The first one is that the electric polarization, induced in bone by an electric field, is due to the Maxwell–Wagner polarization mechanism that the polarization rate is relatively slow, which leads to the electric field force acted on a bone specimen increase gradually and then its bending deflections increase gradually. The second one is that the flexoelectric polarization effect that resists the electric force to decrease and then leads to the bending deflection of a bone cantilever decrease gradually. It is concluded that the first aspect refers to the organic collagens decreasing the electric polarization rate of the bone, and the second one to the inorganic component influencing the bone's polarization intensity. [ABSTRACT FROM AUTHOR]

Highlights: [•] EIS was employed for the first time employed to determine fenvalerate. [•] Pre-treatment for the detection is simple in operation with this technique. [•] This method is label-free with high sensitivity and selectivity, rapidity and low cost. [ABSTRACT FROM AUTHOR]

A novel photochromic diarylethene fluorescence sensor 1o bearing a triazole-linked rhodamine B unit was designed and synthesized. Results showed that 1o had multi-responsive photoswitchable characteristics under the stimulation of light, proton, and specific metal ions. It also showed highly selectivity and sensitivity to recognize Hg2+ over other interfering heavy and transition metal ions through the spirolactam ring-opening reaction, which could be detected with "naked-eyes". Upon the treatment with Hg2+, the fluorescence intensity of 1o at 606 nm was enhanced by 88-fold with notable fluorescence color changing from dark to pink. And its detection limit to Hg2+ was as low as 0.13 μM. Significant fluorescence quenching was observed upon the irradiation with 297 nm light due to FRET between rhodamine B moiety and diarylethene unit. Moreover, an INHIBIT logic gate was established with UV light and proton as the dual data inputs, and the fluorescence intensity at 605 nm as the data output. A novel photochromic diarylethene derivative bearing a triazole-linked rhodamine B unit was synthesized and its multi-addressable switching characteristics with light and chemical stimuli were studied systematically. Image 1 • A novel photochromic diarylethene fluorescence sensor 1o bearing a triazole-linked rhodamine B unit was synthesized. • 1o displayed multi-responsive photoswitchable characteristics under the stimulation of light, proton, and mercuric ion. • The sensor exhibited exhibits both colorimetric and fluorescent response to mercuric ion. [ABSTRACT FROM AUTHOR]

The electromechanical properties of bone may play roles in the growth of bone tissue. The electrostriction effect of bone, which is one of the electromechanical properties of bone, was investigated using the digital image correlation technique (DIC). The advantage of using DIC is that the light beam used for the displacement measurement does not interfere with the electric field exerted on the bone specimen. To measure the bending deflections of a bone cantilever in an electric field, the displacement of the free end surface of the cantilever was measured using the image correlation technique. The experimental results show that the bending direction of the bone cantilevers is independent of the electric field direction and that the bending deflections are proportional to the square of the applied voltages. The attractive force between the charges on the electrode and the unlike charges in the specimen can be equivalent to a uniform distribution load regardless of the thickness of the bone specimen. [ABSTRACT FROM AUTHOR]