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The hard agglomeration of bismuth silicate prepared by sol–gel method is the main reason to hinder its modification, photocatalytic performance and application. In order to better improve the photocatalytic performance of photocatalysts, polystyrene (PS) spheres modified Bi12SiO20–Bi2O2SiO3 composites (PBSO) and silver-loaded PS spheres modified BSO composites (Ag-PBSO) are prepared by PS spheres and photoreduction method. The crystal phase, morphology and optical properties of the catalysts were characterized by XRD, SEM and UV–Vis DRS, respectively. The visible light degradation activity of the photocatalysts is analyzed via ultraviolet-visible spectrophotometer. The results show that the Ag-PBSO photocatalyst can degrade more than 97% of the pollutants within 75 min. This is attributed to the synergy of heterojunction, specific surface area and SPR effect. Among them, after the introduction of PS template, the structure becomes loose and the specific surface area increases. This greatly increases the contact area of the catalyst with pollutants, providing a more robust loading environment for the subsequent Ag. In addition, the SPR effect possessed by Ag can synergize with the large specific surface area to accelerate electron transfer between heterojunctions. This method provides a new idea for the degradation of organic pollutants in the environment. [ABSTRACT FROM AUTHOR]

Unraveling the morphology of the sensing material is of paramount in realizing the better sensitivity. For this purpose, the Bi2Ti2O7:Yb3+/Er3+ nanofibers (0:1, 4:1, 8:1, 15:1, 20:1) and nanoparticles were synthesized via an electrospinning and sol–gel route, respectively. Subsequently, the temperature sensing properties based on the fluorescence intensity ration were studied within Bi2Ti2O7:Yb3+/Er3+ nanofibers and particles in the range of 298–538 K. The maximum relative sensitivity value was 1.53% at 298 K for Bi2Ti2O7:Yb3+/Er3+ (4:1) nanofibers. As was expected, Bi2Ti2O7:Yb3+/Er3+ nanofibers demonstrated an enhanced temperature sensitivity than that of the individual nanoparticles, exhibiting the champion values among all the reported Yb–Er pairs. To exploit the potential for practical application, the Bi2Ti2O7:Yb3+/Er3+ nanofibers were utilized to measure the surface temperature of a heating object. An improved surface temperature resolution was realized compare with the infrared thermal camera. All the presented results confirmed that the novel upconversion Bi2Ti2O7:Yb3+/Er3+ nanofibers could be an outstanding candidate for temperature sensors. Our work has proven to be a reliable alternative for exploring contactless temperature sensing at a higher resolution. [ABSTRACT FROM AUTHOR]

Endowing mesophilic microorganisms with high-temperature resistance is highly desirable for industrial microbial fermentation. Here, we report a cold-shock protein (CspL) that is an RNA chaperone protein from a lactate producing thermophile strain (Bacillus coagulans 2–6), which is able to recombinantly confer strong high-temperature resistance to other microorganisms. Transgenic cspL expression massively enhanced high-temperature growth of Escherichia coli (a 2.4-fold biomass increase at 45 °C) and eukaryote Saccharomyces cerevisiae (a 2.6-fold biomass increase at 36 °C). Importantly, we also found that CspL promotes growth rates at normal temperatures. Mechanistically, bio-layer interferometry characterized CspL's nucleotide-binding functions in vitro, while in vivo we used RNA-Seq and RIP-Seq to reveal CspL's global effects on mRNA accumulation and CspL's direct RNA binding targets, respectively. Thus, beyond establishing how a cold-shock protein chaperone provides high-temperature resistance, our study introduces a strategy that may facilitate industrial thermal fermentation. [ABSTRACT FROM AUTHOR]

The bismuth silicate heterogeneous powders were prepared by Pechini sol–gel method, and Ag–Bi12SiO20/Bi2SiO5 (Ag–BSO) were prepared by photoreduction method. The crystal phase, morphology, crystal structure and optical properties of the samples were systematically characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, FTIR spectrometer and UV–Vis–NIR spectrophotometer. The photocatalytic performance of BSO and Ag–BSO samples with different Ag contents was investigated. The results show that the degradation rate of Rhodamine B in BSO and Ag–BSO system under visible light is about 56% and 90%, respectively. With a suitable concentration of Ag solution, a heterogeneous interface is formed between Ag and BSO, which greatly improves the photocatalytic activity of BSO. Moreover, the synergistic effect of the heterojunction and the heterogeneous interface greatly enhances the photocatalytic performance. [ABSTRACT FROM AUTHOR]

The sillenite compound Bi12SiO20 was synthesized via Pechini sol–gel method. Composition, crystallinity, microscopic appearance, and optical properties of samples were characterized by XRD, SEM, FTIR, and UV/Vis/NIR spectrophotometer. The photocatalytic property of pure Bi12SiO20 was also investigated by detecting the degradation rate of rhodamine B (RhB). The experimental conditions related to the preparation of pure phase bismuth silicate, such as the content of citric acid, calcination temperature schedule, and the molar ratio of Bi/Si were investigated. And when n(citric acid) = 13 mmol, n(Bi/Si) = 10, and heat preservation at 630 °C for 5 h, pure bismuth silicate powder can be successfully synthesized. And the degradation of RhB by Bi12SiO20 under visible light for 150 min can reach to 80%, which indicated that pure Bi12SiO20 is an excellent photocatalyst under the visible light. In addition, the capture experiments demonstrate that (Vo+) dominates in photocatalytic degradation. Highlights: Pure Bi12SiO20 photocatalyst can be successfully synthesized by Pechini method. Bi12SiO20 has a typical sillenite structure with the band gap of 2.4 eV. Bi12SiO20 shows a better visible-light photocatalytic performance than P25. [ABSTRACT FROM AUTHOR]

Herein, SiO2-photonic crystal/TiO2 composite film (STF) with multilayer structure was designed and fabricated via self-assembly method and spin coating method. The micro-morphology and optical properties of the STF were characterized by scanning electron microscope (SEM) and UV/Vis/NIR spectrophotometer respectively. The photocatalytic activity of the STF was tested via the degradation rate of rhodamine B. The characterization results indicate that the STF has a regular ordered structure when the amount of ammonia is 3 mL and the concentration of SiO2 suspension is 1%, and SiO2 can be effectively combined with TiO2, so the STF has the best photocatalytic performance. The double-layer SiO2-photonic crystal/TiO2 composite film (DSTF) was further prepared and compared with the single-layer SiO2-photonic crystal/TiO2 composite film (SSTF). The photocatalytic properties of the DSTF are better than that of the SSTF. Finally, the mechanism of STF with enhanced photocatalytic performance is discussed, indicating that photonic crystal can effectively enhance the utilization of light which are near the wavelength of the center band gap, and then improve the photocatalytic performance of the photocatalyst. [ABSTRACT FROM AUTHOR]

A TiO2-based ternary oxide was synthesized as a visible-light photocatalyst (TiO2/ZrTiO4/SiO2, SZT) by introducing SiO2–ZrO2 into TiO2 through sol–gel method. The related material compositions and microstructures were characterized, and the optical and photochemical performances were evaluated and compared with pure anatase TiO2. By introducing SiO2–ZrO2, the grain size of TiO2 was reduced from 29.9 nm in the pure anatase phase to 11.5 nm in SZT, accompanied by the formation of ZrTiO4. Moreover, the synthesized SZT demonstrated greatly lowered photoluminescence intensity and electrochemical impedance, and significantly increased photocurrent. The new photocatalyst also exhibited superior adsorption and photocatalytic ability for RhB, and higher catalytic stability. The improved photodegradation performance was attributed to the enhanced charge transfer and charge carrier separation as a result of the refined grains, the formation of TiO2/ZrTiO4 heterojunction, and a higher amount of built-in oxygen vacancies. [ABSTRACT FROM AUTHOR]

Co3O4 is often used to detect H2O2. However, there are many problems such as low sensitivity and the long detection time when detecting H2O2 in various cobalt oxide composites. Therefore, it is a great challenge to develop different morphologies of the Co3O4 electrode to improve the detection performances of H2O2 effectively. In this paper, we had successfully prepared a novel Co3O4/reduced graphene oxide/carbon cloth (Co3O4/rGO/CC) composite. We used a simple template method. Co3O4 nanosheets with a diameter of about 47.7 nm were obtained by using graphene oxide as a template. Then, CC was used as a three-dimensional conductive support material. CC can inhibit the agglomeration of rGO to increase specific surface area and to enhance the conductivity of Co3O4. In this study, the electrochemical performances of the Co3O4/rGO/CC electrode were tested by the electrochemical workstation. The trigger response of the modified electrode was reduced by 0.067% and the relative standard deviation was 0.013% after 30 consecutive tests. The range of linearity was 0.387–63.523 mM. Besides, this electrode has the limit of detection (0.022 μM) and a higher sensitivity (0.9683 mA mM−1 cm−2). It indicated that the electrode has excellent electrochemical sensing performance and high stability. These excellent performances are mainly due to the synergistic effect of Co3O4 nanosheets, rGO, and CC. [ABSTRACT FROM AUTHOR]

Novel Bi12SiO20–Bi2SiO5 heterostructure photocatalysts were prepared by controlling the molar ratio of Bi/Si in the reactants via Pechini method. With the increasement of the molar ratio of Bi/Si, the samples tend to be well-crystallized Bi12SiO20 and the content of Bi2SiO5 decreases in composites. Experiments reveal that the heterojunction shows higher visible light photocatalytic activity than pure Bi12SiO20 and Bi2SiO5 due to an increase in light harvesting efficiency and an efficient electron–hole separation. And the heterostructure photocatalyst is stable in the photocatalytic reaction process. The influence of some trapping agents on the photodegradation of Rhodamine B was investigated, and h+ and ·O2− were verified to play more important roles than ·OH−. [ABSTRACT FROM AUTHOR]

BiSiO is a metastable phase compound and one of the important Bi-based Aurivillius phase oxide semiconductors. Pure BiSiO powders were synthesized successfully by Pechini sol-gel method. The samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, thermal analyzer, FTIR spectrometer, Raman spectrometer, fluorescence spectrophotometer and UV/Vis/NIR spectrophotometer. The mechanism of the reaction process was studied. The structure, the optical and photocatalytic properties of pure samples were investigated. The results show that citric acid, polyethylene glycol, solvents and calcination temperature have important effects on the reaction, and pure BiSiO can be obtained at 650 °C for 1 h. The as-prepared BiSiO has a typical Aurivillius-like structure and its bang gap energy is 3.5 eV. The results of degradation of Rhodamine B reveal that pure BiSiO powders prepared by Pechini sol-gel method possess a synergistic effect of adsorption and photocatalysis, which indicates that the BiSiO powders can be used as an efficient material for wastewater treatment. [ABSTRACT FROM AUTHOR]

Using Bi(NO)·5HO and Si(OCH) as the starting materials, citric acid and polyethylene glycol (PEG)-6000 as the complexing agents, pure BiSiO powders with good photocatalytic activity were first prepared at low temperature via Pechini sol-gel method. The effect of calcination temperature on the preparation of pure phase as well as the photocatalytic properties was investigated. The thermal analysis and X-ray diffraction results showed that the crystallization temperature of BiSiO is about 400 °C and pure sample can be obtained at 550 °C. The infrared spectra indicated the pure BiSiO samples have an Aurivillius-like structure. Furthermore, the as-prepared BiSiO exhibited efficient photocatalytic activity in the decomposition of Rhodamine B due to a synergistic effect of adsorption and photocatalysis. [ABSTRACT FROM AUTHOR]

SiO2 colloidal spheres were synthesized by St6ber method. In order to enhance surface charge of the SiO2 spheres, they were modified with succinic acid. Scanning electron microscope (SEM) shows that the average size of modified SiO2 spheres is 473 nm, and its distribution standard deviation is less than 5%; Fourier-transform infrared spectra (FT-IR) and X-ray photoelectron spectrometer (XPS) results indicate that one end of succinic acid is chemically bonded to the SiO2 spheres through esterification; Zeta potential of the modified SiO2 spheres in water solution is improved from -53.72 to -67.46 mV, and surface charge density of the modified SiO2 spheres is enhanced from 0.19 to 0.94 μC/cm². SiO2 colloidal crystal was fabricated from aqueous colloidal solution by the vertical deposition method at 40°C and 60% relative humidity. SEM images show that the sample of SiO2 colloidal crystal is face-centered cubic (fcc) structure with its (111) planes parallel to the substrate. Transmission measurement shows the existence of photonic band gap at 1047 nm. [ABSTRACT FROM AUTHOR]

High salt intake is a known risk factor of cardiovascular diseases. Our recent study demonstrated that long-term high salt intake impairs transient receptor potential channel M5 (TRPM5)-mediated aversion to high salt concentrations, consequently promoting high salt intake and hypertension; however, it remains unknown whether TRPM5 activation ameliorates cardiovascular dysfunction. Herein we found that bitter melon extract (BME) and cucurbitacin E (CuE), a major compound in BME, lowered high salt-induced hypertension. Long-term BME intake significantly enhanced the aversion to high salt concentrations by upregulating TRPM5 expression and function, eventually decreasing excessive salt consumption in mice. Moreover, dietary BME ameliorated high salt-induced cardiovascular dysfunction and angiotensin II-induced hypertension in vivo. The mechanistic evidence demonstrated that dietary BME inhibited high salt-induced RhoA/Rho kinase pathway overactivation, leading to reduced phosphorylation levels of myosin light chain kinase and myosin phosphatase targeting subunit 1. Furthermore, CuE inhibited vasoconstriction by attenuating L-type Ca2+ channel-induced Ca2+ influx in vascular smooth muscle cells. To summarize, our findings indicate that dietary BME has a beneficial role in antagonizing excessive salt consumption and thus appears promising for the prevention of high salt-induced cardiovascular dysfunction. [ABSTRACT FROM AUTHOR]