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The calcium ions (Ca2+) of calcium hydroxyapatite (CaHap) were substituted with zinc ions (Zn2+), and zinc–calcium hydroxyapatite solid solution (ZnCaHap) particles were prepared via a precipitation method. The structure of the various obtained particles was investigated via powder X-ray diffraction, field emission scanning electron microscopy and energy dispersive X-ray spectrometry. The ultraviolet (UV) absorption ability of the particles was also investigated using UV–Vis spectroscopy. The morphology of the CaHap comprised fine ellipsoidal particles, and long rod-like particles and large plate-like particles were mixed with the fine particles at higher Zn2+ contents in the particles. Pure ZnCaHap particles were obtained from the starting solution at less than Zn/(Zn + Ca) ([XZn]) of 0.25. Another crystal phase was mixed with the ZnCaHap phase at [XZn] ≥ 0.25. The crystallinity and lattice parameters a and c of the particles decreased with an increase in [XZn] from 0 to 0.10. The UV absorptive ability of the particles first increased and then decreased with increasing Zn2+ content and showed a maximum at [XZn] = 0.30. [ABSTRACT FROM AUTHOR]

Objective: By analyzing bacteriostasis and efficacy, the possibility of Artemisia argyi extract to be a plant extract preservative is clarified. It provides a message for the development of natural non-irritating plant extract preservative. Methods: Water and ethanol extracts of A. argyi were prepared. The content of its main active components was determined. Its inhibitory effect and stability on Escherichia coli and Staphylococcus aureus were analyzed. Antioxidant activity, ultraviolet absorption capacity and security were also discussed. Results: The ethanol extract of A. argyi had a significant inhibitory effect on the two kinds of bacteria, which was related to the content of active components to some extent. Temperature and UV irradiation had no significant effect on antibacterial activity, while pH had a greater effect on antibacterial activity. At the concentration of 0.96 mg/mL, ethanol extract of A. argyi leaves could eliminate 98% of DPPH and ABTS free radicals, and more than 50% of superoxide anion and hydroxyl free radicals. When the concentration was 0.5 mg/mL, the two extracts had good ultraviolet absorption capacity. The HET-CAM test showed that the extract of A. argyi had high security at the concentration of 62.5 mg/mL. Conclusion: The ethanol extract of A. argyi has good and stable bacteriostatic effect, certain antioxidant activity, ultraviolet absorption performance and security.

Fe 2 O 3 and TiO 2 were used as colorants in borosilicate glass, aimed to form amber-colored pharmaceutical glass. The status of the Fe and Ti ions and their influences on the glass structure were analyzed by FTIR, Raman and Mössbauer spectroscopic technique. The large addition of Fe 2 O 3 led to the decrease of connectivity of silica network and the increase of [BO 3 ]. TiO 2 showed even larger depolymerization effect. Fe3+ coordinated with the bridging oxygen in [SiO 4 ] increasing the aggregation of silica network and the [Fe2+O 6 ] filled the voids of glass network. Both types of iron ions helped to restrain the mobility of Na+ and improved the water resistance of the glass, while TiO 2 as a network modifier did the opposite. Either Fe 2 O 3 - or TiO 2 -containing samples exhibited enhanced UV-absorption capacity. The glass sample containing both Fe 2 O 3 and TiO 2 as colorants completely blocked the UV light, and exhibited the best water resistance. The results obtained herein enriched the understanding of the effects of colorants on borosilicate glasses and could provide useful information for the production of amber glasses used in pharmaceutical packing. [ABSTRACT FROM AUTHOR]

There are few comparative studies of chromophoric dissolved organic matter (CDOM) in humid temperate lakes. In this study, we examined the ultraviolet absorption of water sampled from temperate lakes in Japan and China. A proportional relationship was found between the dissolved organic carbon (DOC) concentration and ultraviolet absorption coefficients in all lake samples, indicating similarities between the two parameters in the temperate lake environments. However, the ratios of absorption coefficient to the DOC concentration in the ranges of < 295 and > 320 nm showed different distributions among the lakes, even within similar DOM component of data sets. We used a two-step ultrafiltration to extract the heterogeneous parts of the CDOM from filtered water. In particular, the low molecular weight fractions in the eutrophic lakes had relative high ratios of absorption coefficient to DOC concentration. These fractions can highlight the CDOM characteristics of lakes in different trophic status. [ABSTRACT FROM AUTHOR]

Exposure to ultraviolet (UV) light is known to cause skin aging, skin damage, cancer, and eye diseases, as well as polymer material aging. Therefore, significant attention has been devoted to the research and development of UV absorbers. Considering the robust hydrogen bonding and conjugated structure present in nitrogen-containing polycyclic compounds, these compounds have been selected as potential candidates for exploring ultraviolet absorption properties. After structural optimization and the simulation of ultraviolet absorption spectra, four tris-[1,2,4]-triazolo-[1,3,5]-triazine (TTTs) derivatives, namely TTTB, TTTD, TTTJ, and TTTL, were selected as the preferred compounds and synthesized. The structure of the compound was determined using various analytical techniques, including FTIR, 1HNMR, 13CNMR, HRMS, and XRD. Subsequently, composite films of polyvinyl chloride (PVC) and TTTs were produced using a simple solvent casting technique. The PVC films were subjected to UV age testing by exposing them to an ultraviolet aging chamber. The age-resistant performance of the fabricated films was evaluated using an ultraviolet spectrophotometer and Fourier infrared spectrum instrument. The findings suggest that TTTs exhibit a noteworthy capacity for absorbing ultraviolet radiation. The TTTL compound exhibits a superior UV absorption performance compared to commercially available UV absorbers such as UV-0 and UV-327 in the market. [ABSTRACT FROM AUTHOR]

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The calcium ions (Ca2+) of calcium hydroxyapatite (CaHap) were substituted with zinc ions (Zn2+), and zinc–calcium hydroxyapatite solid solution (ZnCaHap) particles were prepared via a precipitation method. The structure of the various obtained particles was investigated via powder X-ray diffraction, field emission scanning electron microscopy and energy dispersive X-ray spectrometry. The ultraviolet (UV) absorption ability of the particles was also investigated using UV–Vis spectroscopy. The morphology of the CaHap comprised fine ellipsoidal particles, and long rod-like particles and large plate-like particles were mixed with the fine particles at higher Zn2+ contents in the particles. Pure ZnCaHap particles were obtained from the starting solution at less than Zn/(Zn + Ca) ([XZn]) of 0.25. Another crystal phase was mixed with the ZnCaHap phase at [XZn] ≥ 0.25. The crystallinity and lattice parameters a and c of the particles decreased with an increase in [XZn] from 0 to 0.10. The UV absorptive ability of the particles first increased and then decreased with increasing Zn2+ content and showed a maximum at [XZn] = 0.30.

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• The introduction of the substituent group would cause the UV absorption spectrum of 2-hydroxybenzophenone to be significantly red-shifted, and the substituent group containing N atoms would make the wavelength of the molecule red-shifted to a more obvious extent. • AIM analysis showed that the different substituent positions and species would have different influences on the hydrogen bonding within the molecules of 2-hydroxybenzophenone-based UV absorbers. • NBO analysis further revealed that the type and position of the substituent groups in the molecular structure influenced the strength of the intramolecular hydrogen bonding by affecting the distribution of the charges among individual atoms in the 2-hydroxybenzophenone molecules. 2-Hydroxybenzophenone is the simplest molecule among benzophenone-based UV absorbers. Changing the position and type of substituents affects the strength of intramolecular hydrogen bonding and thus modulates the UV absorption properties. In this work, 132 2-hydroxybenzophenone-based UV absorbers with different substituent positions and species were designed to investigate the substituent effect in their UV absorption properties. The results show that when the substituent positions are the same, the characteristic peaks of the compounds containing substituents of the same group of atoms or homologous groups correspond to similar wavelengths. When the substituent groups are the same, the wavelength redshift of the characteristic peaks of the UV absorption spectra of the compounds of the NX and NZ classes is more pronounced than that of the remaining species, and the substituent group containing N atoms causes the molecule to have a more pronounced wavelength redshift. The redshift of the characteristic absorption peaks corresponding to the wavelengths decreases with the increase of the energy level difference. Atoms-in-molecules (AIM) analysis showed that the electron-absorbing group in the compound enhances the hydrogen bond strength to a lesser extent than the electron-donating group. Natural Bond Orbital (NBO) analysis further revealed that the type and position of the substituent groups in the molecular structure influenced the strength of the intramolecular hydrogen bonding by affecting the distribution of the charges among individual atoms in the 2-hydroxybenzophenone molecules. This work aims to reveal the effect of substituents on the UV absorption properties of 2-hydroxybenzophenone-based molecules and to provide theoretical guidance for the design of such UV absorber molecules absorbing UV light at specific wavelengths. [ABSTRACT FROM AUTHOR]

Thermal, morphological, structural, magnetic, and optical properties of manganite samples with La0.57Pr0.1Sr0.33Mn1−xTixO3 (0 ≤ x ≤ 0.2) compositions were investigated in this work. Thermogravimetric analysis was used to study the percentage weight loss of the compounds during their synthesis by the standard solid-state reaction. Scanning electron microscope (SEM) with an energy dispersive X-ray (EDX) spectrometer shows homogeneous particle distribution and atomic compositions close to the nominal ones. The Rietveld refinement of the X-ray diffractograms revealed that all samples crystallize in the orthorhombic structure with Pnma space group. With Ti substitution, the unit cell volume (V) and average < dMn,Ti–O > bond distance increase, whereas the average < θMn,Ti–O–Mn,Ti > bond angle and the bandwidth (W) decrease. The Curie temperature (TC) decreases from 359 K for x = 0 to 320 K for x = 0.2. Likewise, saturation magnetization (Ms) decreases from 44.992 to 15.452 emu/g by increasing Ti content from x = 0 to x = 0.2, respectively. The decrease of both TC and Ms values was attributed to the structural changes especially to the increase of the bond distance and the decrease of the bandwidth. Additionally, significant lower coercivity values were observed, making the La0.57Pr0.1Sr0.33Mn1-xTixO3 manganites promising candidates for recording media. The prepared samples exhibited remarkable ultraviolet absorption based on the ultraviolet–visible optical absorbance. Estimated values of band gap energy increase from 4.19 eV for x = 0 to 4.38 eV for x = 0.2 which is attributed to the reduction of the bandwidth (W). The variations with a wavelength of penetration depth and extinction coefficient have been also investigated. [ABSTRACT FROM AUTHOR]

The extensive application of a multifunctional composite film of metal nanoparticles embedded in a dielectric matrix is remarkable. Due to the oxidation susceptibility of atomic iron, it is difficult to directly fabricate embedded Fe nanoparticles in an oxide dielectric matrix with a Fe target. Because La 0.5 Sr 0.5 FeO 3 can be decomposed into LaSrFeO 4 and α -Fe, ferromagnetic and optical absorption FePt:LaSrFeO 4 composite films were successfully fabricated at room temperature using Pt and La 0.5 Sr 0.5 FeO 3 as targets via magnetron and pulsed laser co-deposition. Further annealing was performed on the FePt:LaSrFeO 4 composite films. FePt is chemically disordered face-centered cubic phase (A1 structure) below 600 oC annealing and chemically ordered face-centered tetragonal phase (L 1 0 structure) above 600 oC annealing. With increasing the annealing temperature, a redshift of the absorption peak from 256 to 285 nm is seen, which can be attributed to the size growth of the LaSrFeO 4 and FePt nanoparticles in the composite films. The strongest absorption peak at around 269 nm for the 600 oC annealed sample can be attributed to the high crystallographic quality and relatively tiny grain size of FePt particles with uniform distribution. FePt:LaSrFeO 4 composite films are ferromagnetic and optically absorbent, making them suited for multifunctional applications. Furthermore, magnetron and pulsed laser co-deposition techniques have the potential to produce multiferroic oxides, in which the coupling of different ordering processes e. g. ferroelectricity and ferromagnetism provides the potential for a new breed of multifunctional devices. [ABSTRACT FROM AUTHOR]

In recent years, constructing van der Waals (vdW) heterostructures based on different 2D materials has been a highly effective way to obtain desired electronic and optical properties. Herein, on the basis of first‐principles calculations, a 2D vdW heterostructure is constructed by vertically stacking the indirect‐bandgap gallium nitride (GaN) and silicane (SiH) monolayers. For the formed heterostructure, the structural, electronic, and optical properties are all computed. The obtained results show that the heterostructure is a direct‐bandgap semiconductor with typical type‐II band alignment. Furthermore, the linearly tunable bandgap, together with the robust type‐II band alignment, can be realized by applying vertical strains or external electric fields. It is also found that both monolayers exhibit the same UV absorption range and the notably enhanced UV absorption is obtained after forming the heterostructure. In particular, the maximum absorptivity can reach to 21.6%. These results are expected to provide useful references for the design of ultraviolet optoelectronic devices based on the 2D GaN/SiH vdW heterostructure. [ABSTRACT FROM AUTHOR]

Sb single crystals were synthesized via solution method. The Polylactic Acid (PLA) composite membranes modified with monocrystalline Sb powder were prepared by solution blending. In order to investigate the effect of different Sb contents on their properties, the composite membranes were characterized by ultraviolet absorption, contact angle and electrical transport tests. The results illustrated that the ultraviolet absorption peak of composite films red shifted first and then blue shifted with the increase of Sb content. When the Sb content was in the range of 2. 5 % - 5 %, the maximum wavelength of the ultraviolet absorption peak emerged. As Sb grain concentration increased, the hydrophobicity of the composite membranes improved to a certain extent and the conductivity raised constantly. The resistivity of 100% _Sb/PLA_9% composite membranes can reach 31. 85 ± 0. 63 0 • m. In this experiment, the ultraviolet absorption and conductivity of Sb/PLA membranes were regulated by the content of monocrystalline Sb powder, which laid a foundation for the intensive study on the functional composite membrane materials with their performance being controlled by nonferrous metals. [ABSTRACT FROM AUTHOR]

Exposure to ultraviolet (UV) light is known to cause skin aging, skin damage, cancer, and eye diseases, as well as polymer material aging. Therefore, significant attention has been devoted to the research and development of UV absorbers. Considering the robust hydrogen bonding and conjugated structure present in nitrogen-containing polycyclic compounds, these compounds have been selected as potential candidates for exploring ultraviolet absorption properties. After structural optimization and the simulation of ultraviolet absorption spectra, four tris-[1,2,4]-triazolo-[1,3,5]-triazine (TTTs) derivatives, namely TTTB, TTTD, TTTJ, and TTTL, were selected as the preferred compounds and synthesized. The structure of the compound was determined using various analytical techniques, including FTIR, 1HNMR, 13CNMR, HRMS, and XRD. Subsequently, composite films of polyvinyl chloride (PVC) and TTTs were produced using a simple solvent casting technique. The PVC films were subjected to UV age testing by exposing them to an ultraviolet aging chamber. The age-resistant performance of the fabricated films was evaluated using an ultraviolet spectrophotometer and Fourier infrared spectrum instrument. The findings suggest that TTTs exhibit a noteworthy capacity for absorbing ultraviolet radiation. The TTTL compound exhibits a superior UV absorption performance compared to commercially available UV absorbers such as UV-0 and UV-327 in the market.

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Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We evaluated the influences of the priming process (washing with saline), saline circulation conditions, and saline incubation on the in vitro elution of substances from three types of polysulfone (PSu) membrane dialyzers sterilized using gamma irradiation [NV-15X (Toray Industries, Inc.)], autoclaving [RENAK-PS1.6 (Kawasumi Laboratories, Inc.)], or in-line steam [FX-140J (Fresenius Medical Care)] methods as well as a non-PSu cellulose triacetate (CTA) membrane dialyzer [FB-150U(NIPRO)]. The effect of priming was evaluated by circulating 1000 mL of saline through the dialyzers at a rate of 100 mL/min and measuring the elution level of the substances by determining their ultraviolet (UV) absorption at 220 nm using spectrophotometry. All the tested dialyzers showed that the elution of the substances decreased as per the order of sample collection. Primed dialyzers were used in the subsequent experiments. Circulating saline through the primed membrane dialyzers at a flow rate of 100 mL/min caused time-dependent elution of substances from all the tested dialyzers; increasing the flow rate to 200 mL/min did not have a significant effect on the time-dependence or elution amount at each time point (0–8 h). The elution was also evaluated after incubating the membrane dialyzers with saline for 24 h. A co-submitted article (Sato et al., 2021) detailed the preparation of the identical experimental circuits, as well as the influences of saline washing, saline circulation conditions, and saline incubation on the elution of the hydrophilic agent polyvinylpyrrolidone (PVP) from each dialyzer using the Müller method, which can enable specific detection of PVP (Müller, 1968). The relative elution levels of PVP among the dialyzers and the experimental conditions were different from those of substances determined using UV (220 nm) absorption. Our data might be used for further development of experiments for identifying non-PVP substances eluted from dialyzers by providing information regarding the conditions of the elutions and types of dialyzers from which they are eluted.

Hierarchical porous zinc oxide (ZnO)/silver (Ag) microspheres were prepared by two‐step method. The porous ZnO microspheres were prepared firstly, and then Ag nanoparticles were evenly anchored on the surface of ZnO microspheres by Sn2+ activation method. The results show that ZnO is wurtzite phase, and Ag particles are only coated on the surface of ZnO microspheres. Compared with pure ZnO, there are two obvious absorption peaks of Ag‐doped ZnO, which corresponds to the ultraviolet absorption peak of ZnO and the plasma resonance absorption peak of Ag, respectively. The intensities of photoluminescence peak of ZnO/Ag microspheres are significantly lower than that of pure ZnO. Moreover, ZnO/Ag microspheres show higher photocatalytic activity than ZnO, which may be attributed to the existence of highly dispersed Ag. [ABSTRACT FROM AUTHOR]

Growing interests to extend the nanotechnology based on plasmonics with tunable absorption band in the ultraviolet (UV) region require materials which are natural abundance and cost-effective and can open up new possibilities of device applications. Al is one such material which shows strong absorption in UV region. For understanding the shift of surface plasmon resonance (SPR) band of Al nanoparticles (NPs) due to change of particle size, shape, separation, and medium dielectric constant, systematic theoretical studies have been carried out using a simple model. A prominent deep-UV SPR absorption peak (~ 218 nm) has been observed for spherical non-interacting NPs of radius of 20 nm embedded in silica. This peak is seen to blue-shift with decrease in NP radius due to mainly surface-electron damping by the radiation effects. For other cases, a large redshift (in UV region) of the SPR peak has been seen as a function of shape parameter (K), inverse of interaction parameter (1/β), and dielectric constant of surrounding medium. For interacting NPs, the observed redshift of the SPR band has been found to decay exponentially with increase in 1/K and can be explained as due to the increased interaction of the electric fields between NPs. For prolate spheroid NPs, a linear variation of SPR band corresponding to longitudinal oscillations of free electrons of the NPs with increase in 1/β has been seen. Finally, correlations between (i) K and interparticle separation and (ii) β and aspect ratio have been established for the physical realisation of K and β, and practical applications of Al NPs as plasmonic devices. [ABSTRACT FROM AUTHOR]

Improving the dispersion stability of graphene oxide (GO) suspensions is of great importance in many potential applications of GO, such as GO-based laminated membranes used for separation, printable electronics, and aqueous liquid crystals. Molecular dynamics (MD) simulations and quantum chemistry (QC) calculations along with complementary experiments were performed to study the dispersion stability of GO in the mixtures of water and polar organic solvents (dimethyl sulfoxide (DMSO), ethanol, and acetone). GO exhibits better dispersion stability in a solvent mixture than in pure water. The MD simulations uncover the underlying mechanism that mixed solvent layers are formed steadily on the surface of GO sheets and screen the interactions between them. QC calculations reveal that both DMSO and water form hydrogen bonds with the oxidized regions of GO. X-ray diffraction experiments confirm that the GO sheets are intercalated by DMSO and water molecules. Furthermore, the optimal ratio of the organic solvent to water is determined to achieve the best dispersion stability of GO through MD simulations. And such ratio is also verified by ultraviolet absorption spectral experiments. Thus, our findings provide a facile method to prepare GO suspensions with high dispersion stability. [ABSTRACT FROM AUTHOR]

To expand functions of transparent wood (TW) including fluorescence, ultraviolet blocking, heat preservation and insulation, we adopted carbon quantum dots (CQDs) to prepare luminescent transparent wood. CQDs with yellow/red fluorescence (YCD/RCD) were prepared by chitosan and o -phenylenediamine. Afterwards, Balsa woods were pretreated to obtain wood frameworks (DW/LW), which were further combined with epoxy resin for achieving transparent woods (DW-TW/LW-TW). Results showed LW retained more lignin, the LW-TW blocked more ultraviolet light, displaying the better visible transmission and mechanical strength than DW-TW. After adding YCD and RCD to LW-TW, the yellow and red fluorescence transparent woods with outstanding mechanical and ultraviolet blocking properties were prepared, especially the red fluorescence transparent wood (RTW). Specifically, the tensile strength and elongation at break of RTW reached up to 19.39 MPa and 5.35 %, respectively. Moreover, RTW could block 78.8 % of UV-B light and 78 % of UV-A light, respectively. Besides, RTW possessed excellent visible transmission (70.3 %) and UV blocking (88.87 %). Significantly, both RTW and YTW displayed outstanding water repellency, excellent durability, good thermal stability and insulation. Predictably, luminescent transparent woods certainly will enhance the adaptability of wood, and broaden its applications in green decoration, lighting setup, sensor and other fields. [ABSTRACT FROM AUTHOR]

[Display omitted] • The coupling mechanism of BO and VUV technology was first proposed. • BO/VUV effectively removed multiple emerging pollutants without producing secondary pollutants. • The feasibility of the BO/VUV technology was verified in actual water bodies. • BO/VUV treatment reduced tap water toxicity, securing it as a terminal drinking water treatment option. Micropollutant in drinking water may not be effectively removed during centralized treatment. To reduce potential health risks, water treatment at the user terminal is warranted. This study investigated the performance of VUV coupled with boiling to simultaneously remove contaminants, a common household water treatment method in developing countries, for the treatment of micropollutants. Compared to individual boiling or VUV treatment, the VUV/BO process was more effective in improving the degradation of micropollutants. The results showed that heating promoted the direct photolysis and HO oxidation capabilities in the VUV process, with the HO generation increasing from 36.56 μM at 30 °C to 80.48 μM at 90 °C. At a reaction temperature of 100 °C, the degradation rates of malathion (MAL), dimethoate (DMT), trichloroacetic acid (TCAA), and dichloroacetic acid (DCAA) by VUV were increased by 0.81, 1.19, 1.34, and 0.90 times respectively compared to 25 °C. Analysis of the organic composition of actual water samples showed that the total fluorescence intensity of organic matter decreased significantly after VUV oxidation, mainly degrading humic-like substances. Using GC–MS analysis, this study identified 11 oxidative products of the DMT, and proposed two possible degradation pathways. Toxicity evaluation of the intermediate products of DMT demonstrated that they were less toxic than the parent contaminants. The results indicate that the heating-coupled water treatment process provides an effective technology for the treatment of micropollutants in terminal drinking water, and this process is worth promoting in the future. [ABSTRACT FROM AUTHOR]

• Influences of nano-ZnO on physical properties of asphalt were studied. • Anti-aging characteristics of nano-ZnO modified asphalt were analysed. • Fatigue characteristics of nano-ZnO modified asphalt were tested. • Particle size range of nano-ZnO scattering ultraviolet light was calculated with Rayleigh's law. • Interaction mechanism between asphalt and nano-ZnO particles was interpreted. Asphalt aging holds responsibility for fatigue damage of asphalt pavement. Incorporation of nano-zinc oxide (nano-ZnO) as modifier into asphalt can effectively improve anti-aging property of asphalt. In this work, different dosage of nano-ZnO was added to original asphalt to prepare modified asphalt, and physical properties of nano-ZnO modified asphalt, including storage stability, penetration (25 °C), softening point and ductility (5 °C) were tested. Effect of nano-ZnO on the rheological properties of asphalt was studied by testing rheological properties of modified asphalt before and after aging. In addition, fatigue properties of asphalt with different nano-ZnO dosage were analyzed by linear amplitude sweep (LAS) test. Furthermore, anti-aging characteristics of nano-ZnO modified asphalt were characterized by thin film oven test (TFOT) and ultraviolet aging (UV-aging) test and mechanism was interpreted by UV–visible-infrared absorption test. The results show that nano-ZnO can influence penetration (25 °C), softening point, ductility (5 °C) and storage stability of asphalt. Nano-ZnO can improve complex shear modulus (G*), phase angle (δ) and fatigue performance. Addition of nano-ZnO can evidently improve anti-UV aging ability of asphalt and make asphalt show certain viscosity recovery during aging process. In addition, nano-ZnO has strong absorption characteristics to ultraviolet light with more than 95% absorption rate, which reflects its superiority as anti-UV aging modifier for asphalt. UV absorption of nano-ZnO modified asphalt is enhanced several times than that of original asphalt. Asphalt modified with reasonable nano-ZnO dosage possesses significant and evident anti-aging characteristics. [ABSTRACT FROM AUTHOR]

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Abstract With anisotropic particles attracting much attention for both theoretical and practical application considerations, it was critical to simply manufacture the special morphology particles with different structure or/and surface chemistry. Herein, a novel one-step dissolution template method was described to prepare PSt@TiO 2 (Polystyrene @ Titania) navel-like hollow Janus particles (NHJPs). These NHJPs could be obtained simply with dissolution of sulfonated-PSt core template only by regulating the volume ratio of tetrahydrofuran-ethanol solution. The morphologies of these particles were characterized by SEM and TEM. The FT-IR, XPS, XRD and TGA were performed to determine the composition. The formation mechanism of NHJPs was also studied, and the morphology could be control by regulating the dissolution time and the solubility parameters of solvent. The NHJPs showed excellent ultraviolet absorption and the band gap of NHJPs was obtained by UVDRS, which was further proved their highly attractive for photocatalytic materials. Moreover, the preparation method of the PSt@TiO 2 NHJPs presented here was scalable and can be extended to other similar systems. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Copyright of China Textile Leader is the property of China Textile Information Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Dalian Polytechnic University is the property of Journal of Dalian Polytechnic University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A highly efficient strategy for the synthesis of polylactide with the UV absorption ability was established by employing a Salan-yttrium complex (acting as a fast runing catalyst) combined with large excess hydroxyl functionalized benzophenone, BP′-OH. During polymerization, BP′-OH, acting as the chain transfer agent, attached to the active rare-earth metal catalyst via a rapid-reversible exchange reaction to initiate the polymerization. Thus, more polyester chains appeared to grow from one active metal species, and the UV absorption fragments were incorporated into the polymer chains at specific sites, in situ. A high productivity up to 1000 molLA/mol(Salan-Y) was successfully achieved and 100 BP′-labeled PLA chains grew from each active metal center. [ABSTRACT FROM AUTHOR]

ZnO nanorods have been grown on the surface of foamed nickel by a two-step method. Firstly, a layer of ZnO seed is sputtered on the surface of the foamed nickel by magnetron sputtering, and then the hydrothermal method is used to grow ZnO nanorods at different conditions (solution concentration, reaction time and reaction temperature). The results show that the morphology of ZnO nanorods is closely related to the solution concentration, reaction time, and reaction temperature. The energy band structure formed by the foamed nickel and ZnO seed layers and the growth mechanism of ZnO nanorods are discussed. The samples are characterized by Energy dispersive spectrometer (EDS), X-ray diffraction (XRD), and Raman spectroscopy. The absorption characteristics of samples to light are characterized by ultraviolet-to-visible (UV⁻VIS) absorption. The hydrophilicity of the samples is characterized by the static contact angle. By analyzing the performance characteristics of the samples at different conditions, we finally obtained the optimal growth parameters. At the optimal parameters, the morphology of the grown nanorods is regular, the ultraviolet band has strong absorption, and the surface of the samples forms a superhydrophobic surface.

Sb2O3- and CeO2-doped ZnO thin films were prepared by RF magnetron sputtering technique. The influence of Sb2O3 and CeO2 on the structure and ultraviolet (UV) absorption properties was studied by X-ray diffraction and UV-Vis spectrophotometry. Results show that multiple doping of films had a prominent effect on the development of crystal grains and the UV absorption property. Ce and Sb exist in many forms in the ZnO film. The multiple-doped films also show enhanced UVA absorption, and the UV absorption peak widens and the absorption intensity increases. Sb plays a dominant role on the structure and UV absorption of ZnO thin films, which are enhanced by Ce. [ABSTRACT FROM AUTHOR]

Black phosphorus (BP) shows broad application in optical, photoelectric and semiconductor fields. Herein, BP nanosheets and few-layer phosphorene were prepared by means of a solvent exfoliation method. The absorption and fluorescence spectra of BP were measured and dye-sensitized solar cells (DSSCs) were fabricated using BP/TiO2 films as working electrodes. The results show that the light-absorption ability of BP depends on the number of layers and few-layer phosphorene can absorb ultraviolet light (260-325 nm) specifically. The decrease of interfacial transport resistance and the increase of the utilization of sunlight favor the enhanced photoelectric conversion ( η) of ≈38 % compared with TiO2 films. The stability of few-layer phosphorene was also studied and the reduction of the corresponding η was mainly due to the defects caused by chemical etching which impeded electron transport. In all, there is a good reason to believe that if we can find an effective way to solve the seal problems in the devices, few-layer phosphorene will be an excellent candidate in optical, photoelectric and semiconductor fields. [ABSTRACT FROM AUTHOR]

Micron-sized porous composite particles composed of CeO 2 and SiO 2 nanoparticles were prepared for a UV absorption application by an aerosol spray-drying process from as-prepared CeO 2 nanoparticles, commercial SiO 2 , and a polystyrene latex template. The morphology, structure crystallinity and pore size distribution of the as-prepared porous CeO 2 SiO 2 composite particles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Barrett-Joyner-Halenda (BJH) method, respectively. The porous CeO 2 SiO 2 composite particles, with diameters of approximately 10 μm, showed a spherical morphology. As the contents of CeO 2 in the precursor was increased from 0.25 wt% to 1.5 wt%, we observed a change in the morphology of the composite particles from compactly packed porous particles to loosely packed porous particles. The as-prepared CeO 2 SiO 2 composite particles were composed of meso- and macropores in the range of 3–200 nm. The effect of the CeO 2 content on the porous composite particles in terms of the UV absorption properties was also investigated by UV-visible spectroscopy. When the content of CeO 2 exceeded 0.75 wt% in the precursor, the particles showed higher UV absorption values compared to those of commercial TiO 2 nanoparticles. The as-prepared porous CeO 2 SiO 2 composite particles can therefore be promising materials given their high UV absorption value. [ABSTRACT FROM AUTHOR]

Recently the Lee proton electrostatic localization hypothesis has successfully elucidated the decades-longstanding energetic conundrum of ATP synthesis in alkalophilic bacteria. According to the Lee proton electrostatic localization model, the equilibrium constant KPi for non-proton cations such as Na+ to delocalize the localized protons from the membrane-water interface should be much smaller than unity. Through the experimental study reported here, it has now been determined for the first time that the equilibrium constant KPi is indeed far much less than one. The equilibrium constant KPNa+ for sodium (Na+) cations to exchange with the electrostatically localized protons was determined to be (5.07 ± 0.46) x 10-8 while the equilibrium constant KPK+ for potassium (K+) cations to exchange with localized protons was determined to be (6.93 ± 0.91) x 10-8. These results mean that the localized protons at the water-membrane interface are so stable that it requires ten million more sodium (or potassium) cations than protons in the bulk liquid phase to even partially delocalize them at the water-membrane interface. This provides a logical experimental support of the proton electrostatic localization theory. The finding reported here may have fundamental implications in understanding the importance of water to life not only as a solvent and substrate but also as a proton conductor for proton coupling energy transduction. It may also have fundamental implications in understanding the salinity tolerance in biological systems in relation to localized proton coupling bioenergetics. [ABSTRACT FROM AUTHOR]

This is a brief review on changes that occur when dilute aqueous solutions are left standing, motionally unperturbed, in a glass storage container from hours to days. This results in an increase in solution viscosity termed thixotropy. Agitation quickly reduces the viscous weak gel-like state back to its original less viscous state. Other changes include increases in electrical conductivity, laser light scattering, luminescence, and UV adsorption. Both the presence of ions and hydrophilic surface have been shown to be factors in the thixotropic phenomenon of water. It is proposed that a supramolecular structure of water develops from minutes to weeks then reaches a plateau. Biological implications are briefly mentioned. [ABSTRACT FROM AUTHOR]

In order to improve the utilization of industrial lignin as an effective component for ultraviolet (UV) shielding, organic solvent (methanol, ethanol, and acetone) fractionation was applied to improve its UV absorption performance and reduce its apparent color. Physicochemical properties of lignin and lignin-based sunscreens, such as molar mass fraction, functional group content, color change and UV shielding properties, were characterized in detail by GPC, UV spectroscopy, 31P NMR and HSQC-NMR spectroscopy. The results showed that the color and UV-shielding properties of the soluble fraction were significantly superior to those of the original and insoluble fractions. Different lignin fractions were acted as the only active substance in the pure cream and its UV-shielding properties were compared. Among them, the composite sunscreen by adding 5 wt% acetone fractionated lignin had highest sun protection factor (SPF) value of 6.6, approximately 4.5 times higher than those sunscreens mixed with pristine lignin. Overall, this work offers the potential of industrial lignin in value-added applications such as UV protection and cosmetics. • Alkali lignin was separated by solvent fractionation to obtain soluble fraction. • The soluble fraction of lignin had more phenolic hydroxyl groups and lighter color. • Lignin-based sunscreen exhibited higher sun protection factor value. • This work provides a convenient pathway for the value-added utilization of lignin. [ABSTRACT FROM AUTHOR]

To measure chromophoric properties of DOM in aquatic environments is relatively simple, but similarities in properties among extensive DOM samples make it difficult to identify characteristics that indicate different sources of DOM. We conducted a field survey of DOM ultraviolet (UV) absorption and fluorescence in a large lake (Lake Biwa, Japan). We used an integrated analysis of their spectra, including their derivatives and apparent quantum yield. From this analysis we were able to identify the different DOM sources. Variations of dissolved organic carbon concentrations in the epilimnion were correlated with the first derivative of UV absorption at 285 nm and a protein-like peak in the fluorescence excitation–emission matrix (EEM). Both fingerprints were derived from living organisms. Although the variations of UV absorption over 300 nm and a humic-like peak in EEM in the lake water were affected by multiple sources and reactions, several complementary methods, including field studies and laboratory experiments, led to the conclusion that chromophoric DOM in the hypolimnion was intensively affected by microbial alteration. Our results indicate that an integrated analysis of UV absorption and fluorescence can improve the utility of DOM characterization in lake environments. [ABSTRACT FROM AUTHOR]