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The synthesis and photo-luminescence properties of Eu2+/Eu3+ or Ce3+/Eu3+ co-doped Sr 5 (BO 3) 3 F compounds are reported. Using the Sr 5 (BO 3) 3 F as the host, through the solid state reaction under the reductive atmosphere, Eu2+/Eu3+ and Ce3+/Eu3+co-doped samples were prepared. These compounds exhibit good photo-luminescence properties. Under the excitation of 376 nm, an unusual red orange emission coming from the Eu2+ ions can be obtained in Eu ions doped Sr 5 (BO 3) 3 F, which exhibits a broadband emission in the range of 450–800 nm with the peak at around 600 nm. At the same time, the characteristic f-f excitation and emission of Eu3+ can improve and adjust the Eu2+ emission in Eu3+/Eu2+ codoped Sr 5 (BO 3) 3 F. In addition, the adjustable luminescence properties from blue to white of Sr 5 (BO 3) 3 F:Ce3+, Eu3+ are investigated. The energy transfer behavior from Ce3+ to Eu3+ was confirmed. In the spectra of the co-doped samples, we can hardly observe the characteristic peak of Eu2+, because Ce4+ can oxidize Eu2+ to Eu3+, and Ce4+ itself is reduced to Ce3+. The CIE coordinates from (0.2758, 0.2420) to (0.3857, 0.3015) show Sr 5 (BO 3) 3 F:3%Ce3+, x%Eu3+ (x = 1,3,5,7,9) are in the white light emission region. All results demonstrate that the Sr 5 (BO 3) 3 F:Eu3+/Eu2+ and Sr 5 (BO 3) 3 F:Ce3+/Eu3+ phosphors have good application prospects for LED plant growth and white LED, respectively. The bond energy method was used to explain the reason why the Eu2+/Eu3+ ion instead of only Eu2+ and Ce3+/Eu3+ instead of Ce3+/Eu3+/Eu2+ can exist in the host Sr 5 (BO 3) 3 F. The theoretical analysis agree well with the experimental result. [ABSTRACT FROM AUTHOR]

A series of Eu3+/Eu2+ codoped Ca 2 Al 2 SiO 7 were synthesized by traditional solid-state synthesis in reducing atmosphere. In this work, XRD powder diffraction proved that the obtained sample was pure. Photoluminescence properties are characterized by excitation, emission spectra and decay curves. Double center emission is achieved by adjusting excitation wavelength and concentration. Under the 394 nm excitation, the emission spectra Ca 2 Al 2 SiO 7 : Eu phosphors exhibit two bands situated at blue emission of 4f5d-4f transition from Eu2+ ion and red emission of 4f-4f transition coming from Eu3+ ion. The red and yellow light can be obtained when the concentration of doped europium ions is at 0.5% and 1%, respectively. When the excitation wavelength was 394, 280 and 584 nm, the emission color change from yellow to blue, respectively. The bond energy theory explains Eu2+ and Eu3+ ion occupy Ca1 site in the Ca 2 Al 2 SiO 7 lattices. In addition, the spectra show that the abnormal intensity peaks of europium ion at 701 nm can be found. Analysis of the related intensity 5D 0 -7F 2 (618 nm) transition peak is similar to that of 5D 0 -7F 4 (701 nm) transition peak in the emission spectra with the Judd-Ofelt theory. [ABSTRACT FROM AUTHOR]

• Provincial Multi-Regional Input-Output is combined with household survey data. • Tree-models were applied to classify the energy requirement groups. • Mental health plays an influential role in the degree of indirect energy requirements. The United Nations Sustainable Development Goals have highlighted the challenges brought about by increasing energy consumption and climate change. Previous studies have concentrated on accounting for urban and rural household energy requirements in China at a macro-scale, which neglects the analysis of individuals and their socio-economic driving factors at the micro-scale. To fill this gap, this study began with an accounting of energy requirements for urban and rural households based on the provincial Multi-Regional Input-Output (MRIO) tables and household survey covering over 25,000 unique samples from 25 provinces in 2012. Multilinear Regression models were employed to estimate the average effect of various demographic and socioeconomic characteristics of samples, and Tree-based models were applied to classify energy requirement groups and identify the key individual characteristics. The results suggest that the energy requirements per capita on average range from 34 to 211 GJ for urban samples and 34 to 149 GJ for rural samples across different provinces, and that the gap between individuals can be over 100 times. Indirect energy requirements representing above 90% of the total is the focus of the study. Changes in lifestyle factors include eating out, drinking and smoking, were all correlated with indirect energy requirements. Furthermore, the one-child family has had a positive effect on indirect energy requirements, while the two or more children family has had a negative effect. In addition, an individual's mental health plays a role in the level of indirect energy requirements for high-income rural residents, while geographic location plays a key role for urban residents. [ABSTRACT FROM AUTHOR]

A novel luminescent material Sr 5 (BO 3) 3 F:x%Eu3+ was synthesized for the first time by a high temperature solid phase reaction in an air atmosphere. The luminescence properties and site occupancy of Sr 5 (BO 3) 3 F:x%Eu3+ phosphors were studied. The XRD powder diffraction data imply that the series of targets synthesized are pure phases. After repeated experiments, it was found that the main peak position of the excitation and emission spectra changed greatly when the same concentration or different concentration of Eu3+ was doped, and two kinds of spectral phenomena appeared. First, the position of the broadband excitation peak is about 335 nm, and the position of the strongest emission peak belongs to the 5D 0 →7F 0 transition of Eu3+ at 572 nm. Second, the position of the broadband excitation peak is about 275 nm, and the position of the strongest emission peak belongs to the 5D 0 →7F 2 transition of Eu3+ at 619 nm. These imply that different lattice sites are occupied by Eu3+ in Sr 5 (BO 3) 3 F. At the same time, the unusually strong 5D 0 →7F 0 transition illustrates the presence of interstitial oxygen and anomalous crystal field strength in system. A theoretical calculation method of bond energy was applied to study the site occupancy of Eu3+, which shows that any one of Sr1, Sr2, and Sr3 has the possibility of being occupied by Eu3+. Therefore, our test results are consistent well with the theoretical analysis. [ABSTRACT FROM AUTHOR]

Recycling of phosphorus (P) from pyrolysis sewage sludge is a good methodology to deal with the deficit of P resources and safely dispose the sewage sludge. However, it is essential to determine the type of sludge in sewage treatment plants (STPs) along with the most appropriate pyrolysis temperature. These factors affect the form and bioavailability of recoverable P. Thus, four kinds of sludge in a typical STP were selected, and three pyrolysis temperatures including 300, 500, and 700 °C were set to find a suitable strategy for P recovery. The results indicated that with increasing pyrolysis temperature, more organic phosphorus (OP) was transformed into inorganic phosphorus (IP) and more non-apatite inorganic phosphorus (NAIP) was converted to apatite phosphorus (AP, mainly Ca 3 (PO 4) 2 , Ca(H 2 PO 4) 2 , Mg 3 (PO 4) 2 , Ca 3 Mg 3 (PO 4) 4 , and Ca 5 (PO 4) 3 OH). Compared to other sludges, dewatered cake sludge (CS) pyrolyzed at 700 °C had the highest AP content, about 1.1–3.6 times that in other pyrolysis products, and the highest Ca 5 (PO 4) 3 OH content containing 35.8% of total phosphorus (TP). The contents of P-2% citric acid (CA) and neutral ammonium citrate (NAC) in CS obtained by pyrolysis at 500 °C reached 45.6 and 49.6 mg/g, respectively, which were 1.1–3.0 and 1.1–2.8 times that of P-CA and P-NAC in other sludges and their biochars, respectively. Moreover, the diethylenetriaminepentaacetic acid extraction analysis indicated that the good stability of heavy metals in CS-derived biochar was better than that in the feedstock. Hence, to ensure the efficiency and safety of P, CS is used as raw material in STPs to recover P resources. CS-500 can be used as the direct P source of land owing to the highest concentration of bioavailable P (P-CA and P-NAC), while CS-700 can be used to represent a slow-release P fertilizer because it contains the highest concentration of AP. [Display omitted] • High-temperature pyrolysis promoted the conversion of NAIP into AP in sludge. • The AP content of CS-700 was 29.1 mg/g about 1.1–3.6 times that in other biochars. • The fraction of hydroxylapatite in CS-700 achieved 35.8% of TP. • CS-500 had the highest level of P-CA (45.6 mg/g) and P-NAC (49.6 mg/g). • CS has the highest phosphorus recovery potential compared to other sludges in STPs. [ABSTRACT FROM AUTHOR]

As an environmental toxicant, arsenic exposure may cause insulin resistance (IR). Previous studies have shown that pyroptosis plays an important role in the occurrence and development of IR. Although gasdermin D (GSDMD) functions as an executor of pyroptosis, the relationship between GSDMD-mediated pyroptosis and hepatic IR remains unclear. Here, we observed that sodium arsenite (NaAsO 2) activated NOD-like receptors containing pyrin domain 3 (NLRP3) inflammasomes, promoted GSDMD activation, induced pyroptosis and hepatic IR, while GSDMD knockdown attenuated pyroptosis and hepatic IR caused by NaAsO 2. However, GSDMD interference did not affect NLRP3 activation. Ubiquitination modification is widely involved in protein regulation and intracellular signal transduction, and whether it regulates GSDMD and affects its degradation, and exerts effects on arsenic-induced pyroptosis remain unclear. We observed that NaAsO 2 reduced the K48- and K63-linked ubiquitination of GSDMD, thereby inhibiting its degradation through the ubiquitin-proteasome system (UPS) and the autophagy-lysosome pathway (ALP), causing GSDMD to accumulate and lyse into GSDMD-N, which promoted pyroptosis. In summary, we demonstrated that GSDMD participated in arsenic-induced hepatic IR. Moreover, NaAsO 2 reduced GSDMD ubiquitination and decreased its intracellular degradation, aggravating pyroptosis and hepatic IR. We have revealed the molecular mechanism underpinning arsenic-induced IR, and we provide potential solutions for the prevention and treatment of type 2 diabetes (T2D). [Display omitted] • The reduction of GSDMD would attenuate the arsenic-induced pyroptosis and insulin resistance. • Exposure to NaAsO 2 would reduce the ubiquitination level of GSDMD. • Ubiquitinated GSDMD would be degraded by ubiquitin-proteasome system and autophagy-lysosome pathway. [ABSTRACT FROM AUTHOR]

The progesterone (P4) level in body fluids can act as an indicator for early pregnancy diagnosis and offers insight into mammalian somatic function. In this work, we designed an antibody-aptamer based sandwich assay as a cathodic photoelectrochemical (PEC) biosensor for P4 detection. The composites of carbon dots and graphene oxide (CDs-GO) with favorable cathodic photocurrent response were used as photoactive materials on which the antibody (Ab) of P4 was immobilized. Meanwhile, high affinity truncated P4 aptamer was immobilized on Au–CuO–Cu 2 O to act as a bioconjugate. When P4 was present, the aptamer-Au-CuO-Cu 2 O bioconjugate could amplify the cathodic photocurrent of CDs-GO modified electrode through Ab-P4-aptamer interactions. Under optimum conditions, the cathodic photocurrent of the constructed PEC biosensor was found to increase linearly with P4 in a wide concentration range from 0.5 nM to 180 nM, with a low detection limit (3S/N) of 0.17 nΜ. The proposed cathodic PEC sensing platform demonstrated high selectivity, satisfying reproducibility, good stability. The sensor was successfully applied in the determination of P4 in human serum samples. • An antibody-aptamer based sandwich assay for progesterone is proposed. • A cathodic photoelectrochemical biosensor with sandwich structure is designed. • Carbon dots-graphene oxide composites are used as photocathodic materials. • Aptamer-conjugated photoactive nanoparticles provide a signal-on sensing strategy. [ABSTRACT FROM AUTHOR]

CdS–In 2 S 3 heterojunction with enhanced photoelectrochemical (PEC) performance was synthesized to construct dual-mode visible light-induced biosensors for highly sensitive and selective detection of bleomycin (BLM). Due to improved absorption in the visible region and suppressed recombination of electron-hole pairs in the heterojunction, CdS–In 2 S 3 composite exhibited enhanced photocurrent response under visible light illumination. Using CdS–In 2 S 3 as photoactive materials and BLM-binding aptamer as recognition element, a PEC aptasensor displaying a declined photocurrent response to BLM was facilely constructed, which was linear to BLM concentration in the range of 5.0–250 nM. On the other hand, the CdS–In 2 S 3 photoanode was employed to construct a photofuel cell (PFC). In such a PFC, the oxidation of water on CdS–In 2 S 3 photoanode under visible light illumination and the reduction of oxygen on Pt cathode led to the generation of electricity. When BLM-binding aptamer was immobilized on CdS–In 2 S 3 photoanode, the output power of the PFC was inversely proportional to the logarithm of BLM concentration from 10 to 250 nM, offering a visible light-induced self-powered sensing platform for BLM detection. Both of the proposed sensors showed high selectivity, good reproducibility and high stability. They were successfully applied to the determination of BLM in human serum samples. • Iron-free photoelectrochemical sensor for bleomycin detection is developed firstly. • Photofuel cell-based self-powered aptasensor for bleomycin detection is proposed. • CdS–In 2 S 3 heterojunction is used as photoactive materials for sensor construction. • CdS–In 2 S 3 composite is successfully prepared by in situ formation of CdS on In 2 S 3. [ABSTRACT FROM AUTHOR]

Eu-doped MAlSi 2 O 6 (M = Li, Na, K, Rb, Cs) phosphors were synthesized by solid-state reaction in air. The crystal structure and optical properties of the phosphors were investigated by X-ray powder diffraction and photoluminescence. Their emission spectra are composed of some broad bands coming from the 5d-4f transition of Eu 2+ and some sharp emission peaks coming from the f-f transitions of Eu 3+ . The co-existence of Eu 3+ and Eu 2+ cations is detected in MAlSi 2 O 6 :2%Eu, which shows that the unusual Eu 3+ →Eu 2+ reduction process occurs in MAlSi 2 O 6 . The preferential occupancy of Eu 3+ or Eu 2+ in MAlSi 2 O 6 can be calculated to be M + sites by the bond-energy method. The deviation of the Eu 3+ –O 2- bond energy is closed to that of the Eu 2+ –O 2- bond energy, which means that Eu 3+ and Eu 2+ can coexist in air. The abnormal reduction of Eu 3+ to Eu 2+ can be explained by charge compensation model. The doped Eu 3+ was induced to M + and the vacancy ( V M ) may be formed. The vacancy( V M ) acted as a donor of electrons, and the Eu M ∙ ∙ defect acted as an acceptor of electrons. The theoretical result is consistent with the experimental phenomenon. [ABSTRACT FROM AUTHOR]

• Scratched glass with spatial and depth features were tested using ad-hoc CDR test setup. • Optical approach and LEFM were combined to evaluate the effect of surface compressive stress towards scratch. • The residual mechanical performance corresponding to the scratch features can be assessed through the developed approach. Glass products are widely used in building envelopes. Fracture can be triggered accidentally from the glass surface damage such as scratch. This study proposed an approach to assess the flexural performance of the aged monolithic glass panel, which has scratch with spatial and depth information detected via non-contact sensing. The coaxial double ring (CDR) test was conducted for experimentally evaluating the flexural strength on a total number of 160 scratched annealed (AN) and fully tempered (FT) glass specimens. Finite element (FE) analysis was performed to find the exact stress state by considering the geometric non-linear behaviour of glass panel under large deflection. Test and numerical results demonstrate that the scratch depth characterized by a confocal microscope and spatial location can both influence the failure load of FT glass, whereas AN glass is only sensitive to the latter. With combining linear elastic fracture mechanics (LEFM) theory, the relationship between the scratch depth and the residual strength of FT glass can be accurately determined. The spatial and depth characteristics of scratch can then be integrated for the failure load assessment of monolithic FT glass panel. The assessment framework can contribute to the accurate non-destructive assessment on aged architectural glass. [ABSTRACT FROM AUTHOR]

In this research, a one-pot prepared modified sludge bio-hydrochar (IBHC) was prepared to activate persulfate (PS) for the degradation of tetracycline (TC) antibiotic. The obtained IBHC bearing defect structure, dispersed iron and large amounts of surface organic functional groups, acts as an outstanding modified biomass carbonaceous material for catalyzing PS to improve the removal efficiency of TC as high as 99.72%. The IBHC + PS system can remove TC effectively with a relative low IBHC dosage (0.2 g·L−1), limited PS consumption (5 mmol·L−1) and wide pH values (2–10). In addition, the degradation of TC still keep in 94.70% after 5 rounds reuse proving that IBHC possesses excellent stability and practicability. During the activation, both Image 2 and •OH were generated and the contribution of each component on the TC degradation in IBHC + PS system was explored. Furthermore, the degradation pathways of TC were proposed based on the results of LC-MS. Image 1 • An iron loaded sludge bio-hydrochar (IBHC) is synthesized by one-pot carbonization. • The IBHC acts as an outstanding catalyst for PS to degrade 99.72% of TC antibiotic. • The IBHC-catalyzed PS system removes TC effectively in a wide range of pH (2–10). • The degradation efficiency of TC reaches 94.7% in the fifth rounds reuse of IBHC. • TC is degraded due to the cleavage of aromatic ring and N-dealkylation process. [ABSTRACT FROM AUTHOR]

• 73 impact attempts with increasing impact velocity were conducted to test multi-layered laminated glass (MLG) panels as the first attempt of this kind. • A nonlinear dynamic analytical model was proposed to calculate the pre-crack impact response of square MLG. • The indentation dominating the impact failure which haven't been considered in the existing analytical works was introduced into the analytical model. • The key feature of experimental impact force variation was determined and validated with the analytical results. • Parametric study was conducted to investigate the influence of the number of glass layers, glass thickness and ratio, panel size on the impact response. This study presents a combined experimental and analytical study on the impact response of multi-layered laminated glass (MLG) under low-velocity hard body impact before glass breakage. The drop weight impact tests using repeated attempts with increasing impact velocities were firstly performed on 12 MLG panels with double PVB or SG interlayers to record the impact response, high speed fracture process. The experimental results identify that: (1) the indentation is the predominant factor for glass fracture in the examined impact scenarios; (2) the key time interval of the pre-crack impact response is within 0.6 ms. The indentation which hasn't been considered in the existing analytical works was hence introduced into the proposed nonlinear analytical model, which employed third order shear deformation theory and obtained the solutions of motion equations by a two-step perturbation method, according to the former finding. The calculated impact response based on the proposed model was validated with the experimental results within 0.6 ms based on the latter finding and showed satisfactory agreement. A parametric study was subsequently conducted to investigate the influence of factors such as the number of glass layers, glass thickness and ratio, panel size on the pre-crack impact response. The results show the increase of peak force and indentation is more sensitive to the increase of total glass thickness after the thickness reaches 24 mm and presents less sensitivity when the thickness approaches 57 mm. The variation of the glass thickness ratio has no influence on the pre-crack behavior once the total glass thickness is fixed. [Display omitted] [ABSTRACT FROM AUTHOR]

• A combined Voronoi tessellation and finite-discrete element method (FDEM) approach for modelling the post-fracture behaviour of laminated tempered glass was proposed. • Fragments of tempered glass with different surface compressive stresses were modelled as Voronoi cells. • Statistical distribution parameters such as the fragment face numbers, volume and sphericity were adopted to reconstruct the fracture morphology of tempered glass. • Post-fracture behaviour of one triple layered laminated tempered glass block under tension was modelled and validated with experimental data. • Key cohesive parameters for describing the residual interaction between glass fragments were determined. • The influence due to the fragments interaction property, bond levels and fracture morphology on the post-fracture behaviour of laminated tempered glass was investigated. It is reported that the fractured glass panels can contribute to the residual load-bearing capability of laminated glass (LG) after cracking. In order to investigate the stiffness and failure characteristics of LG at the post-fracture stage, a combined Voronoi and finite-discrete element method (FDEM) approach was proposed, which includes reconstructing the post-fracture patterns and carrying out the structural simulation of the post-fracture behaviour. The fracture morphology was determined by introducing Voronoi tessellation defined with statistical parameters such as the fragment face numbers, volume and sphericity. The interaction between glass fragments was captured with the cohesive zone model. One fractured LG block under uniaxial tension, which was taken from a triple layered LG beam with ionoplast interlayers, was modelled and validated with experimentally recorded data. Through iteration analysis, the key cohesive parameters were selected. It was then followed by investigating the influence of the fragment interaction property, the bond level and fracture morphology on the post-fracture behaviour of laminated tempered glass. Results show that the combined cohesion and frictional properties can well represent the residual interaction behaviour between fragments. The frictional property has a significant effect on the post-fracture resistance, and whereas the effect on the stiffness is not that evident. Compared to other cohesive parameters, the cohesive stiffness factors have a predominant effect on both the post-fracture stiffness and resistance. The tension stiffening effect is found to be able to provide a clear increase in post-fracture resistance, which can be up to ten times the original resistance, if the glass-interlayer interface is perfectly bonded. The progressive debonding at glass-interlayer interfaces will lead to the degradation in the loading resistance of fractured LG. A higher bond level can promote the coupling effect between interlayers and mid glass layer for providing increased load resistance after the significant debonding has occurred at the outmost glass-interlayer interface. The effect of fracture morphology on post-fracture performance is not evident in most cases except that the increase in fragment size will lead to a great stiffness growth. Combined Voronoi-FDEM concept for the post-fracture model of laminated tempered glass Image, graphical abstract [ABSTRACT FROM AUTHOR]

Long-term exposure to arsenic can cause liver injury and fibrosis. The activation of hepatic stellate cells (HSCs) plays an essential role in the process of liver fibrosis. We found that NaAsO 2 caused liver damage and fibrosis in vivo , accompanied by excessive collagen deposition and HSCs activation. In addition, NaAsO 2 upregulated autophagy flux, elevated the level of cytoplasmic cathepsin B (CTSB), and activated the NOD-like receptors containing pyrin domain 3 (NLRP3) inflammasome in a subtle way. Consistent with these findings in vivo , we demonstrated that NaAsO 2 -induced activation of HSCs depended on CTSB-mediated NLRP3 inflammasome activation in HSC-t6 cells and rats primary HSCs. Moreover, inhibition of autophagy decreased the cytoplasmic CTSB and alleviated the activation of the NLRP3 inflammasome, thereby attenuating the NaAsO 2 -induced HSCs activation. In summary, these results indicated that NaAsO 2 induced HSCs activation via autophagic-CTSB-NLRP3 inflammasome pathway. These findings may provide a novel insight into the potential mechanism of NaAsO 2 -induced liver fibrosis. Image 1 • Chronic arsenic exposure leads to inflammation and fibrosis in livers. • NLRP3 inflammasome plays a crucial role in the activation of HSCs induced by arsenic. • Autophagy and lysosomal rupture are involved in the arsenic-activated of NLRP3 inflammasome. [ABSTRACT FROM AUTHOR]

Application of biochar as an adsorbent for wastewater treatment has obtained a tremendous research interest owning to their low cost and surface functionality. In this research, an iron loaded sludge biochar was successfully prepared through a simple and economical one-step modification hydrothermal method. The iron loaded sludge biochar possesses large amounts of surface organic functional groups (such as hydroxy, carboxyl and aromatic ring, etc.), smaller particle size (about 10 nm) as well as relative higher surface area (82.780 m2 g−1) than of the pristine one. The selective removal of two kinds of antibiotics by the prepared products was demonstrated. Experimental data was fitted to isotherm and kinetic models, and thermodynamic parameters were also calculated. In the single antibiotic system, the maximum adsorption amount of tetracycline (TC) and doxycycline (DOX) could reach 104.86 and 128.98 mg g−1 at 293.15 K, respectively. In the binary antibiotics system, there was an antagonistic effect between TC and DOX. Furthermore, the adsorption of TC was much more inhibited than that of DOX owning to its deferent steric hindrance of molecular structure. Image 10513 • A sludge based biochar was synthesized and modified by one step hydrothermal method. • The influence of loaded iron on the characteristic of biochar was investigated. • The adsorption of antibiotics is dominant by π-π interaction and hydrogen bonds. • There is an antagonistic effect between TC and DOX in the co-adsorption of them. • The steric hindrance leads the competitiveness of TC is weaker than DOX. [ABSTRACT FROM AUTHOR]