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Limited carriers migration and separation efficiency are key factors affecting the photo-electric catalysis performance of semiconductors. In this paper, the mechanical stress field and temperature field are combined to realize the piezo-pyro-photo-electric catalysis by using the coupling effect of the two external fields, which greatly improves the catalysis performance of Ba 0·7 Sr 0·3 TiO 3 semiconductor. At 20–50 °C alternating heating and cooling, ultrasonic excitation, light and bias conditions, the current density of Ba 0·7 Sr 0·3 TiO 3 increased to 1.01 mA cm−2. It is 1.22 and 1.31 times higher than that of piezo-photo-electric catalysis (0.83 mA cm−2) under single mechanical stress field and pyro-photo-electric catalysis (0.77 mA cm−2) under temperature field, respectively. The coupled external stimulation is beneficial to the improvement of photo-electric catalysis performance. Due to the presence of polarization charge imbalance and piezoelectric/pyroelectric polarization induced built-in electric field piezoelectric/pyroelectric potential, thereby increasing the total concentration of carriers, accelerating the separation and transfer efficiency of carriers. This study realizes the synergistic utilization of various clean energy sources such as solar energy, thermal energy, mechanical energy and electrical energy, and provides a key idea for designing electrodes with excellent catalytic performance. [Display omitted] • Piezo-pyro-photo-electric catalysis of Ba 0·7 Sr 0·3 TiO 3 using a combination of mechanical stress field and temperature field. • The current density of Ba 0·7 Sr 0·3 TiO 3 under two fields is significantly higher than other single conditions. • The induced piezoelectric/pyroelectric potential accelerating charge separation and transfer. • SynErgistic utilization of various clean energy sources can be realized. [ABSTRACT FROM AUTHOR]

Measuring stress is critical in the Civil Engineering. However, established acoustic emission-based techniques can hardly evaluate the stress level which a structure is experiencing. Accordingly, an idea of ‘listening’ to Acoustic Emission (AE) to evaluate critical stress states in reinforced concrete (RC) beams is investigated here. Previous work found that the stress diagram of an RC beam cross section strongly correlates with the corresponding AE event intensity distribution pattern. Therefore, the stress level of this type of structures was estimated by utilising the remarkable correlation in this study. First of all, the stress diagrams of a cross section of an RC beam loaded to failure were analysed, revealing features which had close relations with the stress level of the section. Thanks to the correlation, these features were also extracted from the corresponding distribution patterns of the AE event intensity and then used to estimate the stress state. As a result, the AE Intensity Distribution (AID) analysis approach was developed. Data from an experiment conducted on six RC beams with a Digital Image Correlation (DIC) system and an AE device were adopted to verify the approach. Results showed that the indicators of the approach strongly correlated with the stress levels of the specimens; that the approach can characterise the stress states precisely, with an error of about five per cent in critical stages. Besides the approach, more profound significance of this work lies in that it demonstrated the great capability of an innovative strategy, namely characterising structural behaviours accurately via correlating an AE distribution pattern with the corresponding stress diagram. [ABSTRACT FROM AUTHOR]

Two established techniques for monitoring concrete under loading are Acoustic Emission (AE) and strain gauges. The distribution of strain, along with that of stress, on a beam cross section is well established both theoretically and experimentally. However, the AE distribution through the depth of the cross section has received little attention previously. In addition, the correlation between the AE distribution and that of stress on the section could provide valuable insight into the condition of a structure. Therefore, these topics are experimentally addressed in this article. Specifically, six Reinforced Concrete (RC) beams were tested. AE and Digital Image Correlation (DIC) were employed to monitor the beams during loading. Finally, the AE and stress distributions were analysed. The results showed that AE parameters are capable of characterising behaviours of RC beams in the depth direction. Furthermore, the distribution of AE events strongly correlated with that of compressive stress, especially in the post-reinforcement yielding stage. According to these findings, it is highly possible to estimate stress levels of RC beam structures in engineering and science by adopting the AE technique. [ABSTRACT FROM AUTHOR]

• High heating rate was beneficial to the interaction of coal and waste tire. • Synergetic effect between coal and waste tire in co-pyrolysis process was clarified. • The quantity and quality of pyrolysis oil was improved by co-pyrolysis. • Waste tire as hydrogen donor during co-pyrolysis resulted in more high-quality tar. Co-pyrolysis of coal and waste tire is an important route to realize their clean and efficient utilization. To study the interaction during co-pyrolysis, the rapid infrared-heated fixed-bed reactor was adapted to explore the effects of heating rate, pyrolysis temperature and mixing ratio on the products distribution, tar quality and compositions during the co-pyrolysis of Yulin coal (YL) and waste tire (WT), and the interaction mechanism was also explored. The results show that heating rate, mixing ratio and pyrolysis temperature exerted the synergistic effect during co-pyrolysis. High heating rate was beneficial to the interaction of coal and waste tire, and the maximum positive synergistic effect of tar production was obtained at the heating rate of 10 °C/s. The content of light tar (boiling point < 360 °C) in co-pyrolysis tar increased gradually with amount of WT added in blends. When the mixing ratio of YL/WT was 1:1, the most remarkable difference between the experimental and calculated contents of light tar in tar suggested obvious positive synergy among the blended samples. In addition, gas production was remarkably suppressed during co-pyrolysis. It is analyzed that H-rich free radicals like H or CH 3 produced from the cleavage of aliphatic hydrocarbon chains of WT or other reactions like cyclization stabilize the free radicals from coal pyrolysis and contribute to the improved tar quality and the synergy during co-pyrolysis. [ABSTRACT FROM AUTHOR]

Various structural failure modes exhibit great differences in occurrence probabilities, failure consequences and intrinsic characteristics, etc. Utilising these differences can enhance the effectiveness and efficiency of damage identification research, which has currently received little coverage. Therefore, a new idea, developing mode-specific damage detection methods, is suggested in the paper, with validation on beam structures. Firstly, structural behaviour was investigated from the perspective of stochastic traits and the structure design theory. It was concluded that developing damage detection methods for probabilistically dominant modes had potential to enhance the effectiveness of the identification significantly. Secondly, the strategy was applied to simply supported beams for the purpose of verification. When following the flexural mode, a major failure pattern of the beams, the structures demonstrated a very interesting feature – linearized deflection curves. Hence, damage severity and location indices were defined and an analytical model was built by quantifying the feature and then linking the indices to the curvature of the beams. Thirdly, experiments on reinforced concrete (RC) beams were conducted. The results showed that both the flexural mode and the characteristic of the linearized deflection curves were observed on all specimens; that there was a strong correlation between the damage severity index and the state of the defects on the beams; that the location indices corresponding to damaged and intact sections varied completely differently in quality and quantity. Thus, implementing the mode-specific strategy improves the specificity and efficiency of the damage identification dramatically. [ABSTRACT FROM AUTHOR]

Two-dimensional polymer/nanoparticle (NP) composite superlattice monolayers have attracted great attention, due to their applications in flexible optical, sensing, and electronic devices. The large-scale fabrication of these devices requires large-area superlattice monolayers. However, the preparation of large-area superlattice monolayers of polymer-grafted NP still faces great challenges. Herein, we report a modified Langmuir-Blodgett method for preparing large-area superlattice monolayers of polystyrene-grafted gold NPs (AuNP@PS). This method involves two key steps: pre-assembling the AuNP@PS on a liquid surface using mixed high/low-boiling-point solvent as the spreading solvent and then compressing the pre-assembled film in low-boiling-point solvent vapor. The discrete monolayer islands of AuNP@PS are formed in the pre-assembly process. During the surface compression process, the introduction of solvent vapor facilitates the fusion of AuNP@PS islands to form the continuous superlattice monolayers. Otherwise, discrete films with nonuniform thickness are obtained by compression without solvent vapor. This strategy enables the preparation of large superlattice monolayer films over 100 cm2, which are useful in the manufacture of microelectronic devices. [Display omitted] • A modified Langmuir-Blodgett method for preparing superlattice films is reported. • Superlattice films of polymer-grafted nanoparticles over 100 cm2 can be obtained. • Mixed solvent and solvent vapor facilitate the formation of superlattice monolayers. [ABSTRACT FROM AUTHOR]

Environmental pollution is increasingly becoming a serious global challenge due to various pollutants. Cellulose nanomaterials (CNMs) based membranes originated from green resources and sustainable processes are expected to have great potential in environmental applications due to their nanoscale dimension, high surface area, biodegradability, and biocompatibility as well as renewable capability. To fully unlock this potential, fundamental understandings of the interplay between various tunable parameters of CNMs and the substances to be separated, are required for the rational design and fabrication of CNMs based membranes. This review highlights the recent advances in CNMs membranes for environmental remediation in achieving clean air, water, and green energy. Key parameters that dominate the performances of CNMs membranes are critically assessed. The interactions of CNMs with pollutants, molecules, and ions are analyzed and their selective transport mechanisms in different membrane separation processes are discussed. The challenges and future directions for CNMs membranes are also outlined. [Display omitted] • Recent advances in CNMs membranes for environmental remediation are reviewed. • The versatile applications of CNMs membranes for clean air, water, and energy are highlighted. • The challenges and future directions for CNMs membranes are outlined. [ABSTRACT FROM AUTHOR]

• Recent advances in stimuli-responsive CNMs are reviewed. • Reversible interactions of CNMs that trigger desired responses are highlighted. • Stimuli-responsive CNMs exhibit great potential as smart materials. Stimuli-responsive cellulose nanomaterials (CNMs), which change their physicochemical properties in response to specific stimuli have recently been in the spotlight. A great deal of effort has been dedicated to developing stimuli-responsive CNMs in the past two decades. However, the majority of stimuli-responsive CNMs were achieved via the introduction of stimuli-responsive moieties rather than taking advantage of their inherent switchable hydrogen bonds, electrostatic interactions, and molecular polarization in CNMs. In this review, recent advances and future perspectives of stimuli-responsive CNMs that exploiting the inherent switchable hydrogen bonds, reversible electrostatic interactions, and tunable polarization are highlighted. The principles for designing and assembling such smart CNMs are summarized. Stimuli-responsive CNMs that are sensitive to the changes in humidity, chemical molecules, pH, pressure, and electricity represent tremendous opportunities for making advances in sensors, actuators, biomedical applications due to their sensitivity, specificity, and stability. Additionally, major challenges and future perspectives of stimuli-responsive CNMs are reported. [ABSTRACT FROM AUTHOR]

• The stress distribution in the concrete joints of girder structures is targeted. • The relationship between the stress distribution and the resulting acoustic-emission distribution is studied. • The intensity of acoustic-emission events is found to be correlated closely with the stress. • Both the Kaiser effect and a stress threshold influence the relationship appreciably. The stresses in concrete joints connecting adjacent girders are crucially important for the load-transfer mechanism of these structures but to date have been very difficult to measure. In the present study, an experimental investigation is performed to explore the relationship between the stress distribution and the variation of the resulting acoustic emissions (AEs), which provides a fundamental basis for characterizing these stresses quantitatively. The present paper begins by introducing an analytical solution to the shear-stress distributions along the joints in a girder model. The aforementioned relationship is then explained based on the inherent connections among stress, damage, and AE. To verify the relationship, a reinforced-concrete specimen comprising multiple prefabricated girders connected by cast-in-place concrete joints is tested. The results show that (i) the distribution of the intensity of AE events is strongly correlated with the variation of the corresponding shear stresses in a concrete joint, (ii) a stress threshold is critical for the relationship to hold, and (iii) the Kaiser effect influences the relationship appreciably in two completely different ways. The main impact of the present work is that the relationship is a viable basis for follow-up studies of estimating the actual stresses in the concrete joints of prefabricated structures via AE measurements. [ABSTRACT FROM AUTHOR]

To explore the risk factors for preoperative massive cerebral infarction (MCI) in pediatric patients with moyamoya disease (MMD). Pediatric patients with MMD treated between 2017 and 2022 were enrolled. Logistic regression analysis was performed to identify risk factors for MCI among the patients, and a nomogram was constructed to identify potential predictors of MCI. Receiver operating characteristic (ROC) curves and areas under the curves were calculated to determine the effects of different risk factors. This study included 308 pediatric patients with MMD, including 36 with MCI. The MCI group exhibited an earlier age of onset than the non-MCI group. Significant intergroup differences were observed in familial MMD history, postcirculation involvement, duration from diagnosis to initiation of treatment, Suzuki stage, magnetic resonance angiography (MRA) score, collateral circulation score, and RNF213 p.R4810K variations. Family history, higher MRA score, lower collateral circulation score, and RNF213 p.R4810K variations were substantial risk factors for MCI in pediatric patients with MMD. The nomogram demonstrated excellent discrimination and calibration capabilities. The integrated ROC model, which included all the abovementioned four variables, showed superior diagnostic precision with a sensitivity of 67.86%, specificity of 87.01%, and accuracy of 85.11%. This study showed that family history, elevated MRA score, reduced collateral circulation score, and RNF213 p.R4810K variations are risk factors for MCI in pediatric patients with MMD. The synthesized model including these variables demonstrated superior predictive efficacy; thus, it can facilitate early identification of at-risk patients and timely initiation of appropriate interventions. [ABSTRACT FROM AUTHOR]

Tall buildings can affect the seismic safety of shorter buildings in their vicinities. Majority of the studies have investigated such influences by analyzing the structure-soil-structure interactions in the local vicinity. Considering the large mass and long fundamental period of tall buildings, perturbations during earthquakes can affect a very broad area. Therefore, it is important to investigate the influence of tall buildings from a city-scale perspective. Using the Shanghai Central Business District (CBD) area as an example, this study quantified the influence of tall buildings on the seismic responses of sites and buildings using a nonlinear time history analysis. Different earthquake intensities and building configurations were analyzed, and the effects of tall buildings on the ground motion energies, building responses, and damage states were investigated. These findings indicate the need to consider the seismic safety of shorter buildings surrounded by taller ones. • Site-city interactions considering both building and site nonlinearity are analyzed. • Influence by existence of one tall building is analyzed on a city scale. • Ground velocity can increase by 30% at regions surrounded by tall buildings. • Existence of a tall building may increase responses of an 800-m-away building by 10%. [ABSTRACT FROM AUTHOR]

Titanium extraction slag (TES) is a special waste residue in China's Panxi region. It exhibits low hydration activity because of its high titanium content and carbon- and chlorine-based impurities introduced during production. Thus, TES wastes can only be stored in large quantities. Oil and gas wells' high-temperature and high-pressure environments contribute to TES hydration. However, its hydration activity should be improved to transform it into a well cementing material. The optimal calcination temperature was 550 ℃. Using NaOH (6 %) as an activator, the compressive strength values of the calcined TES cured for 1 and 14 days reach 19.23 and 34.40 MPa, respectively, 65.49 % and 39.78 % higher than those of untreated TES. These values meet oil and gas well cementing construction requirements. X-ray diffraction, 29Si nuclear magnetic resonance, scanning electron microscopy, and other characterization methods indicate that calcination can reduce the content of the glassy phase in TES. However, it induces impurity removal and reduces the degree of glassy phase polymerization. Thus, TES's ion leaching and deposition rates, hydration, and compressive strength after calcination improved. Therefore, the method proposed in this study can be successfully used to convert TES into new cementing materials for large-scale applications. • Enhance the activity of titanium extraction tailings through calcination to meet the requirements of oil and gas well engineering. • The influence of processing technology on the hydration activity of slag glass based on microstructure analysis. • Preliminary research on the industrial utilization of titanium extraction slag can help solve the resource waste and environmental problems caused by titanium extraction slag. [ABSTRACT FROM AUTHOR]

The hot densification process can be used to prepare the biofuel pellets and diversified densification materials with suitable mechanical strength to overcome the natural defects of low energy density and loose structure of biomass wastes and achieve the high value utilization of the renewable resources. In this study, the two typical biomass wastes, cotton stalk (CS) and Chinese fir wood sawdust (WS) are used for the hot densification investigation (85 °C), and the microscopic evolution behavior of the biomass components during the hot densification process is explored through the combination of the component adjustment method and molecular dynamics simulation. The results show that cellulose is the key component to the mechanical strength of biomass pellet, which plays the crucial role of skeleton support in the densification process, and the strength of pellet is positively correlated with the increasing addition ratio of cellulose. Furthermore, crystalline cellulose exhibits the strongest bonding properties in the hot densification process due to the formation of rich hydrogen bonds and the increasing intermolecular attraction force. Lignin has the poorest capability for hydrogen bond formation, and its addition increases the van der Waals repulsive forces, resulting in the poorest densification performance. Hemicellulose shows the better adhesion capability than lignin due to its glassy transition (83.34 °C) and the suitable addition can greatly improve the mechanical property of the pellet, up to 14.26 MPa. There exists the strongest synergistic effect between cellulose and hemicellulose, which is beneficial to the bonding performance between particles to different extent. Hot densification process can promote the formation of hydrogen bond connections between molecules/atoms and the increase of the van der Waals repulsive force in the further compression. The densification performance of biomass is the combined effect of the physical forces, including electrostatic force and van der Waals force. • Biomass pellets with different components ratio were obtained. • Effect of components ratio on mechanical properties of biomass pellet was described. • Synergistic effect of double-components in hot densification process is gained. • Intermolecular forces of biomass components in hot densification were investigated. • Densification mechanism was studied by components adjustment and molecular simulation. [ABSTRACT FROM AUTHOR]

Hypoxia-inducible factor-2 (HIF-2), a heterodimeric transcriptional protein consisting of HIF-2α and aryl hydrocarbon receptor nuclear translocator (ARNT) subunits, has a broad transcriptional profile that plays a vital role in human oxygen metabolism. M1001 , a HIF-2 agonist identified by high-throughput screening (HTS), is capable of altering the conformation of Tyr281 of the HIF-2α PAS-B domain and enhancing the affinity of HIF-2α and ARNT for transcriptional activation. M1002 , an analog of M1001 , shows improved efficacy than M1001. However, the cocrystal structure of M1001 and HIF-2 has some defects in revealing the agonist binding mode due to the relatively low resolution, while the binding mode of M1002 remained unexplored. To in-depth understand agonist binding profiles, herein, the molecular dynamic (MD) simulations was applied to construct a stable agonist-protein model, and a possible binding mode was proposed through the analysis of the binding free energy and hydrogen bonding of the simulation results. Nine compounds were then synthesized and evaluated to verify the proposed binding mode. Among them, compound 10 manifested improved agonistic activity and reduced toxicity compared to M1002. This study provides deep insight into the binding mode of such HIF-2 agonists, which would be useful for designing novel agonists for HIF-2. Image 1 • A reliable HIF-2 agonist binding mode is proposed by molecular dynamic simulations. • Nine HIF-2 agonist analogs are synthesized and evaluated to verify the binding mode. • Compound 10 with improved activity and reduced cytotoxicity is obtained. [ABSTRACT FROM AUTHOR]

Objective: Although diabetic kidney disease (DKD) has been considered as a glomerulocentric disease in the past few decades, growing evidence demonstrated that tubular damage was indispensable in its pathogenesis and progression. This study was designed to investigate the association of urinary acidification dysfunction with the progression of DKD in type 2 diabetic patients.Methods: Here the urinary acidification functions were measured from 80 participants with renal biopsy-proven DKD. The different kinds of renal tubular transportation dysfunction were analyzed, including the dysfunction of bicarbonate reabsorption, titratable acid secretion, and ammonium secretion. In addition, patients were followed up for 17 (interquartile range, 11-32) months to evaluate the effect of urinary acidification dysfunction in the progression of DKD.Results: The most common urinary acidification dysfunction was the disorder of ammonium secretion, accounting for 53.75%. The more proteinuria excretion and the lower glomerular filtration rate (GFR) were observed in the urinary titratable acid disorder group than the normal group, and the same results were obtained for ammonium secretion disorder. Urine titratable acid was positively correlated with eGFR whereas it was inversely correlated with proteinuria, serum creatinine, and BUN. Moreover, 24 h urine protein, serum creatinine, BUN and cystatin C increased from DKD stage II to stage IV, whereas the eGFR and urine titratable acid decreased in the same way. Furthermore, Kaplan-Meier analysis and Cox regression showed that the disorder of titratable acid was an independent risk factor for DKD progression.Conclusions: The dysfunction of urinary titratable acid is a potential biomarker for the severity of proteinuria, eGFR and glomerular lesions in patients with DKD. Moreover, the titratable acid disorder is an independent risk factor of the DKD progression. [ABSTRACT FROM AUTHOR]