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The ZnO-10, ZnO-20, ZnO-30, and ZnO-40 nanopetal-shaped samples were successfully synthesized by a hydrothermal method. The results of XRD, SEM, TEM, and BET indicate that the micro–nano petal-like samples have the advantages of high purity, good crystallinity, and large specific surface area. The ZnO-20 sample with the largest specific surface area and pore volume was prepared by adjusting the scheme without changing the sample morphology. The specific surface area and pore volume of the sample were 33.6914m²/g and 0.1561ml/g. The results of gas sensitivity test show that the sample has the highest response and super good gas sensitivity selectivity. At 250^∘C, the responses to 5ppm and 50ppm ethylene glycol can reach 14.4 and 293, respectively. Because of the excellent gas performance of ZnO nanosheets, this work can provide a theoretical basis for the research and development of ultra-sensitive ethylene glycol gas sensors in the industry.

In this paper, we report the first examples of amphiphilic metal(II) complexes of 5,10,15,20-tetraaryl-5,15-diazaporphyrinoids (M-TADAPs) containing triethylene glycol (TriEG) or tetraethylene glycol (TetEG) auxiliaries. A common dipyrrin precursor substituted with TriEG or TetEG groups underwent metal-templated cyclization with zinc(II), nickel(II), or copper(II) acetate to afford the corresponding TriEG- or TetEG-appended M-TADAPs (M = Zn, Ni, Cu) as air-stable 19$\pi$-electron radical cations. These 19$\pi$-electron M-TADAPs were reversibly interconvertible with 20$\pi$-electron antiaromatic M-TADAPs and 18$\pi$-electron aromatic M-TADAP dications by redox reactions. The newly prepared M-TADAPs were basically amphiphilic, but their water solubilities varied considerably depending on the charge of the diazaporphyrin (DAP) ring and the number of ethylene glycol units. The neutral 20$\pi$-electron M-TADAPs were poorly soluble in water, whereas the 18$\pi$-electron M-TADAP dications were soluble in water. Cyclic voltammetry of all M-TADAP derivatives revealed 20$\pi$/19$\pi$-electron and 19$\pi$/18$\pi$-electron redox couples in both CH₂Cl₂ and H₂O with appropriate electrolytes. The addition of M$\prime$X (M$\prime$ = Li, Na; X = Cl, OH) or HCl to aqueous solutions of the M-TADAPs highlighted their reactivities with anions and changes in pH. When treated with M$\prime$X in H₂O, the 19$\pi$-electron M-TADAP radical cations underwent anion exchange but the 18$\pi$-electron Zn-TADAP dications were reduced to the corresponding 19$\pi$-electron species. Upon treatment with HCl in H₂O, the 19$\pi$-electron M-TADAP radical cations underwent one-electron oxidation of the DAP ring, and the resulting 18$\pi$/19$\pi$-electron abundance ratio increased with decreasing solution pH.

Optical immersion clearing is a technique that has been widely studied for more than two decades and that is used to originate a temporary transparency effect in biological tissues. If applied in cooperation with clinical methods it provides optimization of diagnosis and treatment procedures. This technique turns biological tissues more transparent through two main mechanisms — tissue dehydration and refractive index (RI) matching between tissue components. Such matching is obtained by partial replacement of interstitial water by a biocompatible agent that presents higher RI and it can be completely reversible by natural rehydration in vivo or by assisted rehydration in ex vivo tissues. Experimental data to characterize and discriminate between the two mechanisms and to find new ones are necessary. Using a simple method, based on collimated transmittance and thickness measurements made from muscle samples under treatment, we have estimated the diffusion properties of glucose, ethylene glycol (EG) and water that were used to perform such characterization and discrimination. Comparing these properties with data from literature that characterize their diffusion in water we have observed that muscle cell membrane permeability limits agent and water diffusion in the muscle. The same experimental data has allowed to calculate the optical clearing (OC) efficiency and make an interpretation of the internal changes that occurred in muscle during the treatments. The same methodology can now be used to perform similar studies with other agents and in other tissues in order to solve engineering problems at design of inexpensive and robust technologies for a considerable improvement of optical tomographic techniques with better contrast and in-depth imaging.