•Influences of lightweight aggregate on static/dynamic mechanical properties of steam-cured concrete were investigated.•The relationship between elastic modulus, damping ratio and compressive ...strength of steam-cured concrete incorporating lightweight aggregates were established.•The mechanisms responsible for mechanical characteristics of steam-cured concrete with lightweight aggregate were discussed.
In order to mitigate the thermal damage of steam curing process at elevated temperature on microstructure of concrete and thus prepare high quality steam-cured concrete, the effects of type and absorbing-water rate of lightweight aggregate on static and dynamic mechanical properties of steam-cured concrete were investigated by serials experiments in present paper. The temperature evolution of different positions in steam-cured concrete without and with lightweight aggregate during steam curing period was also tested. Result indicates that, compared to control sample without lightweight aggregate, the compressive strength of steam-cured concrete with 30% ceramsite sand replacing the same volume river sand is slightly higher while the one of sample with 30% expanded clay ceramsite is lower at 28-day age. Under the same compressive strength level, the static/dynamic elastic modulus of steam-cured concrete with 30% lightweight aggregate is lower than that of control sample, and the damping ratio of steam-cured concrete with 30% ceramsite sand is higher. Incorporation of lightweight aggregate into concrete will result in a delay of temperature rise, which is very important for alleviating the thermal damage of steam-cured concrete caused by elevated temperature at early age and thus is favourable of improving the compressive strength.
In this paper, we study the existence and concentration of normalized solutions to the supercritical nonlinear Schrödinger equation
\ \left\{\begin{array}{@{}ll} -\Delta u + V(x) u = \mu_q u + a ...\vert u \vert ^q u & {\rm in}\ \mathbb{R}^2,\\ \int_{\mathbb{R}^2} \vert u \vert ^2\,{\rm d}x =1, & \end{array} \right.\where μq is the Lagrange multiplier. For ellipse-shaped potentials V(x), we show that for q > 2 close to 2, the equation admits an excited solution uq, and furthermore, we study the limiting behaviour of uq when q → 2+. Particularly, we describe precisely the blow-up formation of the excited state uq.
•The paper deals with a fast diffusion equation in the whole space with a nonlocal term. We motivate the problem by pointing out such equations are important in processes demanding fast ...solidification, for instance, on repairs in an urgent accident or in submarine engineering.•The aim of the paper is to provide the critical Fujita exponent and the second critical exponent for problem (2.3). And we show the effect of weight function K(x) and coefficient q in nonlocal term on the evolution of solutions. We find that the large s (i.e. small K(x)) or the large q is beneficial to the global existence of solutions.
Fast diffusion is of great importance in concrete solidification, and this paper suggests a modified Fick law to deduce a fast diffusion equation with a nonlocal source. Its global and non-global solutions are obtained, and the critical Fujita exponent and second critical exponent are discussed. A numerical example is given to elucidate the basic properties of the fast diffusion process. The theoretical results shed a promising light on an extremely fast solidification of a concrete in building an artificial island or an urgent repairing in an accident.
Supraparticles (SPs) are agglomerates of smaller particles, which show promising applications in catalysis, sensing, and so forth. Preparation of SPs with controlled sizes, components, and structures ...in an efficient, scalable, and environmentally friendly way has become an urgent demand for the development of SPs. Herein, a method to fabricate SPs based on the Leidenfrost phenomenon is described. By dropping a nano-/microparticle dispersion on a metal plate at the Leidenfrost temperature (T LF) or higher, the solvent evaporates quickly, and SPs can be formed within 1 min. To understand the influence of various factors on the properties of SPs, and also to optimize the fabrication of SPs, the effects of metal surface roughness and primary particle concentration on T LF were carefully observed. Plates with a higher roughness as well as a higher primary particle concentration could trigger a lower T LF. Combining the regulation of composition and volume of the droplets, SPs with different sizes, compositions, and structures were precisely fabricated. Furthermore, highly porous titanium dioxide (TiO2) SPs with enhanced photocatalytic performance were fabricated via this method, showing the merits of the method in practical applications. This simple, efficient, and green method provides a new approach for controlled and large-scale fabrication of SPs with various functions.
Photoacoustic computed tomography (PACT), an emerging imaging modality in preclinical cancer research, can provide multiparametric 3D information about structures, physiological functions, and ...pharmacokinetics. Here, we demonstrate the use of high-definition 3D multiparametric PACT imaging of both primary and metastatic tumors in living mice to noninvasively monitor angiogenesis, carcinogenesis, hypoxia, and pharmacokinetics. The high-definition PACT system with a 1024-element hemispherical ultrasound transducer array provides an isotropic spatial resolution of 380 μm, an effective volumetric field-of-view of 12.8 mm × 12.8 mm × 12.8 mm without scanning, and an acquisition time of <30 s for a whole mouse body. Initially, we monitor the structural progression of the tumor microenvironment (e.g., angiogenesis and vessel tortuosity) after tumor cell inoculation. Then, we analyze the change in oxygen saturation of the tumor during carcinogenesis, verifying induced hypoxia in the tumor's core region. Finally, the whole-body pharmacokinetics are photoacoustically imaged after intravenous injection of micelle-loaded IR780 dye, and the in vivo PACT results are validated in vivo and ex vivo by fluorescence imaging. By employing the premium PACT system and applying multiparametric analyses to subcutaneous primary tumors and metastatic liver tumors, we demonstrate that this PACT system can provide multiparametric analyses for comprehensive cancer research.Photoacoustic computed tomography (PACT), an emerging imaging modality in preclinical cancer research, can provide multiparametric 3D information about structures, physiological functions, and pharmacokinetics. Here, we demonstrate the use of high-definition 3D multiparametric PACT imaging of both primary and metastatic tumors in living mice to noninvasively monitor angiogenesis, carcinogenesis, hypoxia, and pharmacokinetics. The high-definition PACT system with a 1024-element hemispherical ultrasound transducer array provides an isotropic spatial resolution of 380 μm, an effective volumetric field-of-view of 12.8 mm × 12.8 mm × 12.8 mm without scanning, and an acquisition time of <30 s for a whole mouse body. Initially, we monitor the structural progression of the tumor microenvironment (e.g., angiogenesis and vessel tortuosity) after tumor cell inoculation. Then, we analyze the change in oxygen saturation of the tumor during carcinogenesis, verifying induced hypoxia in the tumor's core region. Finally, the whole-body pharmacokinetics are photoacoustically imaged after intravenous injection of micelle-loaded IR780 dye, and the in vivo PACT results are validated in vivo and ex vivo by fluorescence imaging. By employing the premium PACT system and applying multiparametric analyses to subcutaneous primary tumors and metastatic liver tumors, we demonstrate that this PACT system can provide multiparametric analyses for comprehensive cancer research.
The massive use of acetaminophen (APAP) poses a potential crisis for humans and the environment. In this paper, the degradation of APAP in aqueous solution was carried out using photocatalytic ...synergistic persulfate oxidation. To enhance the photocatalytic activity of g-C
3
N
4
and thus activate the persulfate (K
2
S
2
O
8
, PS) more effectively, the heterojunction photocatalyst TiO
2
/g-C
3
N
4
(TCN) was prepared by a hydrothermal method. The TCN-PS catalytic system showed a high efficiency for APAP degradation. When the amount of TCN and PS added was 0.6 g/L, the degradation rate of APAP at 10 mg/L was 78.3% after 60 min of illumination. Moreover, the TCN-PS catalytic system was effective in removing organic pollutants in acidic, neutral, and weakly alkaline environments. The radical quenching experiment results indicate that both sulfate radicals (SO
4
−
•) and hydroxyl radicals (•OH) are involved in the degradation reaction. After five cycles, the TCN-PS catalytic system still has stable catalytic activity.
Significance The assessment of liver function plays an important role in the diagnosis of nonalcoholic fatty liver disease (NAFLD). Current noninvasive imaging methods have limited applicability in ...this regard. Aim We report an application of multispectral photoacoustic imaging (PAI), an emerging modality, to visualize lipid accumulation and liver function in NAFLD. Approach We first demonstrated the liver function reserve with indocyanine green (ICG) to verify the organ’s dysfunction due to NAFLD in a rabbit model. We then noninvasively quantified lipid content in the liver using multispectral PAI. The in vivo PAI results were compared and verified with photoacoustic ex vivo images and liver biopsy. Results A significant difference in the lipidmean value was observed lipidmean = 0.081 ± 0.0161 arbitrary units (a.u.) control versus NAFLD 0.198 ± 0.048 a.u., P = 0.003. Similar to in vivo analysis, a significant difference in lipidmean was observed (lipidmean = 0.0673 ± 0.0165 versus 0.486 ± 0.073 a.u., P < 0.0001) between control and NAFLD group ex vivo. For liver function, the control group showed a rapid decrease after the peak point, whereas the elimination of ICG for the NAFLD group was slower. Conclusions Our study shows that PAI has the potential to provide a noninvasive biomarker for the assessment of liver function and lipid accumulation for NAFLD diagnosis and treatment.
We develop a new Gibbs free energy-based association model and perform series of molecular dynamics (MD) simulations to study the association behavior of Lennard-Jones (LJ) particles in nanoconfined ...aqueous solution. In the association model, the total Gibbs free energy is the sum of free energy cost in the nucleation of a densely packed cluster with an isotropic shape and a radius dependent interfacial tension coefficient, and the translation entropy of dispersed particles outside the cluster. Two key theoretical expressions – total Gibbs free energy formula and the thermodynamic equilibrium equation – are obtained to estimate the cluster aggregation number for a given LJ particle number and the corresponding total Gibbs free energy. Using MD simulations, we observe that the association state transforms from the stable dispersion state, through the reversible state, finally to the stable aggregation state as the LJ particle number increases. In the reversible state, the system reversibly switch in between the dispersion and aggregation states. The existence of three types of association states is also found for LJ particles with the varied well depth. According to our model, the Gibbs free energy curve shows from a single minimum, through two minima, finally to a single minimum, leading to the transformation of association states. The occurrence of reversible state transition is attributed to the free energy barrier of the order of thermal fluctuation in water between the dispersion and aggregation states. These findings deepen the understanding of nucleation/aggregation of hydrophobic gas molecules or particles in solution under nanoconfinement.
•LJ particles show dispersion, reversible, aggregation states in nanoconfined solution.•Three association states still exist even if the well depth changes.•A Gibbs free energy-based association model is developed.•The Gibbs free energy profile shows two minima in the reversible state.•The free energy barrier is the order of thermal fluctuation.
•Myocardial infarction induces anxiety-like behavior in adult female rat.•Echocardiographic indices are positive correlation with anxiety-like behavior.•Myocardial infarction promotes cellular ...neuroinflammation and apoptosis in the hippocampus.•Myocardial infarction induces epigenetic signaling alterations in the hippocampus.
Epidemiological and experimental animal studies indicate that there is a high risk for the incidence of neuropsychiatric disorders suffering from cardiovascular diseases such as myocardial infarction (MI). However, the potential mechanism of this association remains largely unknown. This study sought to evaluate whether epigenetic alterations in the hippocampus is associated with MI-induced anxiety-like behavior in rats. MI was induced by occlusion of the left anterior descending artery in adult female rats. Anxiety-like behavior was examined by elevated plus maze, light-dark box, and open field test. Relative gene and protein levels expression in the hippocampus were tested by qRT-PCR and western blotting, respectively. We found that MI rats exhibited anxiety-like behavior compared with those in controls, and there is a positive correlation between MI and anxiety-like behavior. We also found that MI decreased KDM6B while increased SIRT1 expression in the hippocampus of MI rats relative to those in controls. In addition, MI not only increased levels of IL-1β, bax, and cleaved-caspase 3, but also increased Iba-1 and GFAP expression in the hippocampus, as compared to those in controls, suggesting a promotion of neuro-inflammation and apoptosis in hippocampus. Co-immunoprecipitation assay illustrated that H3K27me3 functioned by counteracting with YAP activation in the hippocampus of MI rats relative to those in controls. Together, these results suggest a potential role of hippocampal epigenetic signaling in MI-induced anxiety-like behavior in rats, and pharmacological targeting KDM6B or SIRT1 could be a strategy to ameliorate anxiety-like behavior induced by MI.
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