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Integrating responsive photonic crystals (RPCs) and quantum dots (QDs) effectively to realize multimode dynamic color regulation is of great significance for promoting advances in color display science. Herein, a new type of flexible dynamic color display with multimode reversible switching between transparent and colorful states based on the combination of RPCs and CdTe QDs is designed. This unique system is fabricated by encapsulating a thin layer of ordered arrays of SiO2@CdTe@SiO2 (SQS) colloids with poly(dimethylsiloxane) (PDMS), which generates an elastic film with sandwiched structure of PDMS/SQS/PDMS. Owing to the similarity in the optical properties of PDMS and SQS, the display is highly transparent in the normal state. Moreover, the resultant flexible display exhibits obvious change in color by mechanical stimuli or UV exposure. Finally, the ability to display joints motion amplitudes of human body as well as the applications in advanced security is demonstrated. [ABSTRACT FROM AUTHOR]

The concrete shear walls of masonry structures with RC frames on the first story are low-rise shear walls with a height–width ratio of less than 1. The strength, stiffness, and ductility of these low-rise shear walls are not matched, resulting in poor seismic performance. Based on the idea of the passive control theory and multi-seismic defensive lines, the scheme of a masonry structure with RC frames on the first story with a concrete-filled steel tubular (CFST) dampers is proposed in this paper. To explore the seismic mitigation effect of CFST dampers applied to a masonry structure with RC frames on the first story, the seismic performance under low-reversed cyclic loading of the frame with the CFST dampers is first compared with that of the energy-dissipated low-rise concrete shear wall proposed by previous researchers and the ordinary low-rise concrete shear wall. Furthermore, the response of the masonry structure model with RC frames on the first story with CFST dampers and two other comparative structural models under earthquake action are discussed. The results show that a masonry structure with RC frames on the first story with CFST dampers has a fuller hysteretic loop, lighter pinching, better energy dissipation ability, and better seismic performance. Compared with the other two structures, the energy dissipation capacity of the masonry structure with RC frames on the first story with CFST dampers is significantly improved, by 1.25~1.5 times. The amplification effect of the deformation angle allows the CFST dampers to play a significant role in energy dissipation, whereas the main structure still undergoes a small deformation. The CFST dampers can dissipate more seismic energy to protect the main structure from damage and improve the seismic performance of masonry structures with RC frames on the first story. [ABSTRACT FROM AUTHOR]

The high porosity of the three-dimensional ordered macroporous structure of inverse opal photonic crystals (IOPCs) provides an ideal platform for gas sensing based on metal oxide semiconductors. Herein, Pt cluster-loaded In2O3 IOPCs were fabricated, and displayed a significantly improved response to ethanol. Various characterization techniques were used to verify the successful preparation of Pt cluster-loaded In2O3 IOPCs. In2O3 IOPCs exhibit closely arranged three-dimensional (3D) ordered macroporous structures, which contain periodic voids with an average diameter of about 150 nm and a uniform wall thickness of 20 nm. Their gas sensing performance is significantly improved at a Pt cluster loading of 2.0 wt%. Gas sensor tests showed that Pt cluster-loaded In2O3 IOPC sensors exhibited an excellent ethanol response (Ra/Rg = 103 to 50 ppm at 240 °C), which was more than 5 times higher than the response of pure In2O3 IOPCs. The sensor also demonstrated an ultra-fast response/recovery time (7/9 s), impressive selectivity, reproducibility, and long-term stability. The significantly enhanced sensing performance of Pt cluster-loaded In2O3 IOPCs is attributed to the synergistic effects of the connected 3D ordered macroporous structure, chemical and electronic sensitization of Pt nanoparticles, and p–n heterojunctions between p-type PtO, p-type PtO2 and n-type In2O3. The present findings are expected to provide enlightening insights into the design and fabrication of gas sensors with an ultra-high response and an ultra-fast response/recovery speed. [ABSTRACT FROM AUTHOR]

CH4 sensors based on metal oxide semiconductors (MOS) provide high sensitivity and fast response, but the sensitivity will be lost when they are poisoned by silicone. Therefore, there is an urgent need to address the poisoning deactivation of MOS gas sensors caused by silicone. Here, the unique strategy of coating a reactive anti-poisoning material onto the surface of the sensing material is proposed to effectively improve the anti-poisoning ability without degrading the gas sensing performance. As an experimental verification, SnO2/α-Al2O3 is designed as the anti-poisoning layer and SnO2 loaded with precious metals (Pt and Pd) as the sensing layer. Owing to the protection of the anti-poisoning layer, the response (Ra/Rg = 24.69) and the response/recovery time (1/24 s) of the sensor to CH4 remained undiminished at 364 °C after being poisoned under an air/hexamethyldisiloxane (HMDSO) (10 ppm) environment for 40 min, which meets the requirements of the Chinese National Standard (GB 15322.2-2019). The mechanism analysis shows that HMDSO can be decomposed with the adsorbed oxygen on the surface of SnO2 in the anti-poisoning layer, and CH4 can diffuse into the sensing layer to be detected. The unique anti-poisoning strategies can provide a promising insight for improving the poisoning tolerance of MOS gas sensors. [ABSTRACT FROM AUTHOR]

Background: Mitochondrial DNA (mtDNA) profiles and contributions of mtDNA variants to CD4+T-cell recovery in Euramerican people living with HIV (PLWH) may not be transferred to East-Asian PLWH, highlighting the need to consider more regional studies. We aimed to identify mtDNA characteristics and mutations that explain the variability of short-term CD4+T-cell recovery in East-Asian PLWH. Method: Eight hundred fifty-six newly reported antiretroviral therapy (ART)-naïve Chinese PLWH from the Comparative HIV and Aging Research in Taizhou (CHART) cohort (Zhejiang Province, Eastern China) were enrolled. MtDNA was extracted from peripheral whole blood of those PLWH at HIV diagnosis, amplified, and sequenced using polymerase chain reaction and gene array. Characterization metrics such as mutational diversity and momentum were developed to delineate baseline mtDNA mutational patterns in ART-naïve PLWH. The associations between mtDNA genome-wide single nucleotide variants and CD4+T-cell recovery after short-term (within ~48 weeks) ART in 724 PLWH were examined using bootstrapping median regressions. Results: Of 856 participants, 74.18% and 25.82% were male and female, respectively. The median age was 37 years; 94.51% were of the major Han ethnicity, and 69.04% and 28.62% were of the heterosexual and homosexual transmission, respectively. We identified 2,352 types of mtDNA mutations and mtDNA regions D-loop , ND5 , CYB , or RNR1 with highest mutational diversity or volume. Female PLWH rather than male PLWH at the baseline showed remarkable age-related uptrends of momentum and mutational diversity as well as correlations between CD4+T <200 (cells/μl) and age-related uptrends of mutational diversity in many mtDNA regions. After adjustments of important sociodemographic and clinical variables, m.1005T>C, m.1824T>C, m.3394T>C, m.4491G>A, m.7828A>G, m.9814T>C, m.10586G>A, m.12338T>C, m.13708G>A, and m.14308T>C (at the Bonferroni-corrected significance) were negatively associated with short-term CD4+T-cell recovery whereas m.93A>G, m.15218A>G, and m.16399A>G were positively associated with short-term CD4+T-cell recovery. Conclusion: Our baseline mtDNA characterization stresses the attention to East-Asian female PLWH at risk of CD4+T-cell loss-related aging and noncommunicable chronic diseases. Furthermore, mtDNA variants identified in regression analyses account for heterogeneity in short-term CD4+T-cell recovery of East-Asian PLWH. These results may help individualize the East-Asian immune recovery strategies under complicated HIV management caused by CD4+T-cell loss. [ABSTRACT FROM AUTHOR]

A series of willemite based ceramics Zn2Ge1+xO4+2x with − 0.1 ≤ x ≤ 0.2 were prepared by the solid-state reaction method. Influences of Ge nonstoichiometry on the crystal structure, densification, and microwave dielectric properties were evaluated in terms of X-ray diffraction, SEM, dielectric measurements and far-infrared spectra. Ge excess favored the formation of single-phase willemite but a high level of excess induced appearance of GeO2. In contrast, nominal composition and those with Ge deficiency comprised of ZnO and the willemite phase. Ge excess was found to be beneficial to the densification and dielectric properties optimization of Zn2Ge1+xO4+2x. A composition with x = 0.1 (Zn2Ge1.1O4.2) exhibited the optimum microwave dielectric properties with a relative permittivity εr ~ 7.09, a quality factor Q × f ~ 112,700 GHz (at 14.48 GHz), and a temperature coefficient of resonance frequency τf ~ − 51 ppm/°C. [ABSTRACT FROM AUTHOR]

BACKGROUND: Simultaneous removal of arsenic and fluoride anions from water by adsorption remains a challenge for environmental remediation practice. To address this issue, four mesoporous bimetallic oxides (MBOs) were prepared via the evaporation‐induced self‐assembly (EISA) method and studied as adsorbents for the co‐uptake of arsenate (As(V)) and fluoride (F−) from synthetic wastewater. Adsorption envelope and equilibrium experiments were performed to investigate the adsorption behaviors and properties. RESULTS: These composites possessed high surface areas (e.g. 200 m2 g−1 for meso‐Ti/Al) and well‐defined mesopores, enabling high adsorption capacities for both As(V) and F−. The maximum adsorption capacities of mesoporous titanium‐lanthanum oxide (meso‐Ti/La) were as high as 81.42 mg g−1 and 44.37 mg g−1 for As(V) and F−, respectively. Surface complexation modeling indicates that As(V) removal mainly involved bidentate surface complexation with surface ≡Me‐OH, while F− was retained by formation of monodentate surface complexes. CONCLUSION: The removal mechanisms were confirmed by X‐ray photoelectron spectroscopy. These MBOs were found to be effective for simultaneous removal of arsenic and fluoride from water. This study also demonstrated that the incorporation of multi‐components and mesoporosity into one composite is an efficient strategy for design and application of high‐efficiency adsorbents for environmental remediation of aqueous contaminants. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: As an external stimulus for stimuli‐responsive chromic materials, a magnetic field has the benefits of contactless control, instant action, and ease of integration into electronic devices. Hence, the development of a magnetically responsive photonic crystal provides a new platform for color displays. However, magnetically controlled display systems have been primarily limited to liquid systems of colloidal crystals; their application to solid chromic systems has been difficult because the ordered array structure is fixed by a polymer network. A novel solid magnetochromic photonic hydrogel is developed that enables colorimetric responses to an alternating magnetic field (AMF). This notable magnetochromic performance is attributed to the superior magnetothermal effect of 1D aggregates of magnetic chains fixed in a thermosensitive hydrogel. The AMF‐responsive magnetic hydrogel exhibits excellent stability for repeated use. This study presents a basis for the development of responsive solid materials with new optical effects for future chromatic applications. [ABSTRACT FROM AUTHOR]

Organic polymeric microspheres, which can be easily synthesized through simple emulsion polymerization, are important building blocks of photonic crystal structural color materials. However, the poor heat resistance of organic polymeric photonic crystals is the intrinsic drawback that severely limits their practical application. In this study, novel polymeric photonic crystal structures with robust heat resistance are developed from the self-assembly of thiodiphenol–formaldehyde (TPF) microspheres. TPF microspheres with controllable particle size and high monodispersity are synthesized through polycondensation and cross-linking reaction between 4,4′-thiodiphenol and formaldehyde via a hydrothermal process. Derived from the highly cross-linked network structure and high content of aromatic rings and sulfur atoms of the TPF microspheres, the obtained polymeric photonic crystals exhibit bright structural colors and excellent heat resistance up to 250 °C. By contrast, general polystyrene photonic crystals possess poor heat resistance (＜110 °C), due to the linear macromolecular structure. The distinct heat resistance feature of TPF structural colors is highly important for expanding their practical applications. [ABSTRACT FROM AUTHOR]

In this study, a class F fly ash and palygorskite have been acid-modified and then evaluated for the adsorption of phosphate in aqueous solution via bench-scale batch experiments. XRD, XRF, SEM, and FTIR were employed to characterize the acid-modified fly ash (MFA) and palygorskite (MPal). Both MFA and MPal show enhanced phosphate adsorption after the modification treatment. The effects of pH, adsorbent dosage, and co-ions on phosphate adsorption, as well as adsorption thermodynamics and kinetics, and leaching features of spent (used) adsorbents were also investigated. The isotherms data fit well with the Langmuir model rather than the Freundlich model, giving maximum capacities (298 K) of 13.3 mg P g − 1 for MFA and 10.5 mg P g − 1 for MPal, respectively. Surface complexation modeling of P adsorption data with the nonelectrostatic generalized composite (GC) approach indicates that phosphate were directly bound to the metal centers by ligand exchange to form two monodentate complexes, ≡ SHPO 4 − and ≡ SPO 4 2 − . The GC model appears to be an easy and efficient tool to provide an insight into the mechanism of phosphate adsorption on complex adsorbents with limited model parameters. Leaching test results suggest that the spent adsorbents can be safely disposed or further reused. [ABSTRACT FROM AUTHOR]