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A new 3D Terbium (III) metal-organic framework has been solvothermally synthesized by using terbium ion as the metal center and 1,1${}^{\prime }$,1${}^{\prime \prime }$-(2,4,6-trimethylphenyl-1,3,5-tri) trimethyl tritrium (4-carboxylpyridyl) tribromide (H₃LBr₃) as ligand. The molecular formula is [Tb(H₃LBr₃) (OH)₂](NO₃)●(DMAC)₃. Compound crystallizes in the triclinic system, space group $P-1$, with $a=9.5747(8)$, $b=12.8667(10)$, $c=18.9440(14)$Å, $\alpha =107.619{(2)}^{\circ }$, $\beta =99.057{(2)}^{\circ }$, $\gamma =97.615{(3)}^{\circ }$, $V=2156.0(3)$ų, $Z=2$, $M_r=1041.85$, $D_c=1.605$g/cm³, $\mu =1.717$mm${}^{-1}$, $F(000)=1068$, $R=0.0583$ and $wR=0.1262$ for 7586 observed reflections ($I>2\sigma$ (I)). Meanwhile, the fluorescence property was also studied. The result shows that the synthesized Tb-MOF displays highly selective sensing of acetone.

This paper presents comparative analysis of different wavelength ranges for the spectroscopic detection of acetone vapor. We collected and analyzed original absorption line spectra arising from electronic transitions in the ultraviolet, near-infrared vibrational overtones, mid-infrared fundamentals, THz torsional modes, and mm-wave rotational transitions. Peak absorption cross sections of prominent spectral features are determined. The relative merit of each spectral range for sensing is considered, taking into account the absorption strength, available technology, and possible interferences.

Cr-containing mesoporous silicates (Cr-FSM-16) were prepared and characterized by several spectroscopic analyses. Their photocatalytic reactivity for acetone under UV- and visible-light irradiations has been investigated and the effect of adsorption on the reactivity was discussed. XPS spectra showed the Cr-oxide moieties were in the mesoporous framework of FSM-16. The UV-VIS spectra of the Cr-FSM-16 exhibited three distinct absorption bands, which could be assigned to charge transfer from O^2- to Cr⁶⁺ of the tetrahedrally coordinated moieties. In particular, the band at 460 nm was assigned to the symmetry-forbidden nature of the ¹A₁ → ¹T₁ transition of tetrahedral Cr-oxide. The absorption showed Cr-FSM-16 has the photocatalytic reactivity under visible light irradiation. Acetone was adsorbed strongly on Cr-FSM-16, and then adsorbed acetone was decomposed to CO₂ and H₂O on Cr-FSM-16 under visible light irradiation. But the amount of CO₂ produced was much less than the stoichiometric amount of CO₂ calculated from adsorbed acetone. This may be due to adsorption of acetone, and/or CO₂ on Cr-FSM-16.

In this paper, first we investigate the heating-responsive shape memory effect in an acrylonitrile butadiene styrene (ABS). Subsequently, after surface treatment (via dipping in acetone/water solution of different concentrations and for different dipping time) of pre-stretched samples, we demonstrate the feasibility to form strip shaped wrinkles atop the surface upon heating of pre-stretched ABS for shape recovery. The influential factors, such as acetone concentration and dipping time in surface treatment, are revealed and discussed.

Experimental studies of the Raman scattering of the band of C = O vibrations of acetone (1710 cm^–1) showed that the parallel and perpendicular polarized components have a large half-width (respectively, 11.6 and 18 cm^–1) and also the bands' maxima of these components are shifted by ~5 cm^–1. In the neutral solvent (heptane), the difference of the maxima position of the bands decreases. Calculations showed that the molecules of acetone can aggregate to form a dimer with the energy gain of 10.1 kJ/mole. In the dimer several hydrogen bonds are formed between the oxygen atom of one molecule and the hydrogen atoms of CH₃-group of another molecule. In an aqueous mixture of acetone, according to calculations, there is a possibility for formation of dimers and closed trimer aggregates with the energy gain, respectively, 19.1 and 45.8 kJ/mole. Calculation showed that symmetric and antisymmetric O–H vibrations of water are displaced in the interaction with acetone to lower frequencies, respectively, to 3808.4 and to 3931.8 ^–1.

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Aniline is oxidized to nitrosobenzene as the initial product, which undergoes further oxidation to nitrobenzene. The nitrosobenzene formation is catalyzed by functionalized multiwalled carbon nanotubes (CNT) followed by a coupling reaction between nitrosobenzene and aniline to produce azobenzene. This coupling requires close proximity of the reactants. It proceeds rapidly resulting in the UV-VIS absorption spectrum showing maxima at 327 nm and 425 nm. The nitrosobenzene yield in the presence of CNTs is controlled by the amount present in the medium. As the reaction is not catalyzed by unfunctionalized CNTs or graphitic particles, the uniqueness of the functionalized multiwalled CNTs in this catalysis suggests a nanodimensional reaction pathway.

With ion-sensitive field-effect transistor (ISFET) studied in this paper, nano-TiO₂-Al₂O₃ insulation film was used as the gate electrode of ISFET. By this means, acetone was analyzed indirectly by detecting hydrogen ion dissociated from acetone solution. Under electric field function, the improvement of decomposition efficiency of acetone and the catalysis of nano-TiO₂ improved the sensitivity of sensor greatly. Based on experiments, the paper verified the effect of electric field and catalysis of nano-TiO₂.

Pure and Eu-doped (1.0, 3.0, 5.0wt.%) $\alpha$-Fe₂O₃ (PFO and EFO) nanotubes and nanowires have been successfully synthesized through the combination of electrospinning and calcination techniques. The structures, morphologies and chemical compositions of the as-obtained products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric and differential scanning calorimetry (TG-DSC) and energy dispersive spectrum (EDS), respectively. To demonstrate the superior gas sensing performance of the doped nanotubes, a contrastive gas sensing study between PFO (EFO) nanotubes and nanowires was performed. It turned out that Eu doping could magnify the impact of morphology on gas sensitivity. Specifically, at the optimum operating temperature of 240${}^{\circ }$C, the response value of PFO nanotubes to 100ppm acetone is slightly higher than that of nanowires (3.59/2.20). EFO (3.0wt.%) nanotubes have a response of 84.05, which is almost 2.7 times as high as that of nanowires (31.54). Moreover, they possess more rapid response/recovery time (11s and 36s, respectively) than nanowires (17s and 40s, respectively). The lowest detection limit for acetone is 0.1ppm and its response is 2.15. In addition, both of EFO nanotubes and nanowires sensors have a good linearity (0.1–500ppm) and favorable selectivity in acetone detection.

Today, fossil carbon provides us with fuels (energy), polymers (packaging, insulating and building materials, household utensils, glues, coatings, textiles, 3D-printing inks, furnitures, vehicle parts, toys, electronic and medical devices, etc.) and biologically active substances (drugs (Chapter 9), flavorings, fragrances, food additives, plant protection products, etc.). In this chapter we discover the modern materials of our civilization which are very often polymers derived from oil. They are referred to as “plastics” (annual world production: 380 × 10⁶ tons). Their production consumes 8% of the crude oil extracted (ca. 5 billion tons per year). An increasing part of the plastics originates from renewable resources (less than 10% today, see Section 11.10, bio-sourced plastics). Plastics make life easy for us, but at the underestimated cost of damage to our environment (Figure 8.1) and our health. They contaminate the hydrosphere and the agricultural soil. The atmosphere is also contaminated by microplastics…

This paper presents comparative analysis of different wavelength ranges for the spectroscopic detection of acetone vapor. We collected and analyzed original absorption line spectra arising from electronic transitions in the ultraviolet, near-infrared vibrational overtones, mid-infrared fundamentals, THz torsional modes, and mm-wave rotational transitions. Peak absorption cross sections of prominent spectral features are determined. The relative merit of each spectral range for sensing is considered, taking into account the absorption strength, available technology, and possible interferences.