The Expert Panel for Cosmetic Ingredient Safety (Panel) assessed the safety of 27 inorganic and organometallic zinc salts as used in cosmetic formulations; these salts are specifically of the 2+ (II) ...oxidation state cation of zinc. These ingredients included in this report have various reported functions in cosmetics, including hair conditioning agents, skin conditioning agents, cosmetic astringents, cosmetic biocides, preservatives, oral care agents, buffering agents, bulking agents, chelating agents, and viscosity increasing agents. The Panel reviewed the relevant data for these ingredients, and concluded that these 27 ingredients are safe in cosmetics in the present practices of use and concentration described in this safety assessment when formulated to be non-irritating.
The two enantiomers of chiral phosphonate 4-phenyldinaphtho2,1-d:1′,2′-f1,3,2dioxaphosphepine 4-oxide, O=PPh(BINOL), were synthesized from the proper 1,1′-bi-2-naphtol (BINOL) enantiomer and ...characterized. The structure of the (S)-enantiomer was elucidated by means of single-crystal X-ray diffraction. The reaction with anhydrous ZnBrsub.2 afforded complexes having the general formula ZnBrsub.2{O=PPh(BINOL)}sub.2 that showed intense fluorescence centered in the near-UV region rationalized on the basis of TD-DFT calculations. The corresponding Mn(II) complexes with the general formula MnXsub.2{O=PPh(BINOL)}sub.2 (X = Cl, Br) exhibited dual emission upon excitation with UV light, with the relative intensity of the bands dependent upon the choice of the halide. The highest energy transition is comparable with that of the Zn(II) complex, while the lowest energy emission falls in the red region of the spectrum and is characterized by lifetimes in the hundreds of microseconds range. Although the emission at lower energy can also be achieved by direct excitation of the metal center, the luminescence decay curves suggest that the band in the red range is possibly derived from BINOL-centered excited states populated by intersystem crossing.
In this study, a new series of phosphors, Casub.9−xZnxGdsub.0.9(POsub.4)sub.7:0.1Eusup.3+ (x = 0.00–1.00, step dx 0.05), was synthesized, consisting of centro- and non-centrosymmetric phases with ...β-Casub.3(POsub.4)sub.2-type structure. Crystal structures with space groups R3c (0.00 ≤ x < 0.35) and R3¯c (x > 0.8) were determined using X-ray powder diffraction and the method of optical second harmonic generation. In the region 0.35 ≤ x ≤ 0.75, phases R3c and R3¯c were present simultaneously. Refinement of the Casub.8ZnGd(POsub.4)sub.7 crystal structure with the Rietveld method showed that 71% of Gdsup.3+ ions are in M3 sites and 29% are in M1 sites. A luminescent spectroscopy study of Casub.9−xZnxGdsub.0.9(POsub.4)sub.7:0.1Eusup.3+ indicated the energy transfer from the crystalline host to the Gdsup.3+ and Eusup.3+ luminescent centers. The maximum Eusup.3+ luminescence intensity corresponds to the composition with x = 1.
The article presents a systematic study of Sb-doped Znsub.1−xMgsub.xO layers, with various concentrations of Mg, that were successfully grown by plasma-assisted MBE on polar a- and c-oriented and ...non-polar r-oriented sapphire substrates. X-ray diffraction confirmed the polar c-orientation of alloys grown on c-and a-oriented sapphire and non-polar structures grown on r-oriented substrates. A uniform depth distribution of the Sb dopant at level of 2 × 10sup.20 cmsup.−3 was determined by SIMS measurements. Raman spectroscopy revealed the presence of Sb-related modes in all samples. It also showed that Mg alloying reduces the compressive strain associated with Sb doping in ZnO. XPS analysis indicates that the chemical state of Sb atoms in ZnMgO is 3+, suggesting a substitutional position of Sbsub.Zn, probably associated with two Vsub.Zn vacancies. Luminescence and transmission spectra were measured to determine the band gaps of the Znsub.1−xMgsub.xO layers. The band gap energies extracted from the transmittance measurements differ slightly for the a, c, and r substrate orientations, and the differences increase with increasing Mg content, despite identical growth conditions. The differences between the energy gaps, determined from transmission and PL peaks, are closely correlated with the Stokes shift and increase with the Mg content in the analyzed series of ZnMgO layers.
Ongoing interest is focused on aqueous zinc ion batteries (ZIBs) for mass‐production energy storage systems as a result of their affordability, safety, and high energy density. Ensuring the stability ...of the electrode/electrolyte interface is of particular importance for prolonging the cycling ability to meet the practical requirements of rechargeable batteries. Zinc anodes exhibit poor cycle life and low coulombic efficiency, stemming from the severe dendrite growth, and irreversible byproducts such as H2 and inactive ZnO. Great efforts have recently been devoted to zinc anode protection for designing high‐performance ZIBs. However, the intrinsic origins of zinc plating/striping are poorly understood, which greatly delay its potential applications. Rather than focusing on battery metrics, this review delves deeply into the underlying science that triggers the deposition/dissolution of zinc ions. Furthermore, recent advances in modulating the zinc coordination environment, uniforming interfacial electric fields, and inducing zinc deposition are highlighted and summarized. Finally, perspectives and suggestions are provided for designing highly stable zinc anodes for the industrialization of the aqueous rechargeable ZIBs in the near future.
By delving deeply into the underlying science that triggers the deposition/dissolution of zinc ions, the recent advances in modulating the zinc ion coordination environment, uniforming interfacial electric fields, and inducing zinc deposition are summarized. Finally, perspectives and suggestions for designing a highly stable zinc anode for the industrialization of the aqueous rechargeable Zn ion battery in the near future are provided.
The current study applies the eco-friendly principle of “wastes treat wastes”. By swift methods, a composite photocatalyst was prepared from waste-extracted oxides, namely Vsub.2Osub.5, Ag, and ZnO. ...The metal–lixiviant complexes were used as metal precursors, where the lixiviants act as auto-templates and increase the compatibility between the mixed metallic species, and their controlled thermal removal generates pores. The tri-constitute composite catalyst was doped with nitrogen. The constitution, surface composition, and optical properties of the doped catalysts were investigated by XRD, SEM, TEM, BET surface analysis, XPS, diffuse reflectance, and PL spectra. The as-prepared catalysts were employed in the photodegradation of Congo red dye (CR) under visible irradiation at ambient temperature. The degree of Ag dispersion had a significant effect on the bandgap, as did metal and metal-nonmetal co-doping. The efficiency of dye removal changes dramatically with time up to 120 min, after which it begins to decrease. According to the pH effect, the normal pH of Congo red dye (6.12) is optimal. At a catalyst dose of 1 g Lsup.−1 and an irradiation period of 120 min, photodegradation efficiency reached 89.9% and 83.4% over Agsub.0.05 ZnOsub.0.05 Vsub.2Osub.5(0.90) and Agsub.0.05 ZnOsub.0.05 Vsub.2Osub.5(0.90)sub.N, respectively. The kinetic study depicted the significant role of mass transfer in the reaction rate. The obtained rate constants were 0.995 mole Lsup.−1 Ssup.−1 and 0.998 mole Lsup.−1 Ssup.−1 for Agsub.0.05 ZnOsub.0.05 Vsub.2Osub.5(0.90) and Agsub.0.05 ZnOsub.0.05 Vsub.2Osub.5(0.90)sub.N, respectively.
Scope
The oral absorption, distribution, excretion, and bioavailability of zinc sulfate (ZnS), zinc gluconate (ZnG), and zinc‐enriched yeast (ZnY) in rats are fully and systemically compared for the ...first time.
Methods and results
After zinc compounds were orally administered to rats at a single dose of 4 mg Zn kg–1, blood, tissues, urine, and feces at different time points were collected for the quantification of zinc concentration. Blood was also harvested for the zinc assay in the multiple‐dose administration. Plasma zinc levels among three zinc compounds showed no difference, and zinc was widely distributed in various tissues with the level sequence of bone > liver > pancreas > testes. The net Zn balance was 2.993, 5.125, and 7.482% for ZnS, ZnG, and ZnY, respectively.
Conclusion
ZnS, ZnG, and ZnY show equivalent bioavailability based on plasma and tissues zinc levels, although ZnY was statistically more absorbed and retained than ZnS and ZnG based on the excretion amount.
After zinc sulfate (ZnS), zinc gluconate (ZnG), and zinc‐enriched yeast (ZnY) are orally administered to rats, plasma, tissues, urine, and feces at different time points are collected for the quantification of zinc concentration. The oral absorption, distribution, excretion, and bioavailability of ZnS, ZnG, and ZnY are compared.
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