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A common retaining structure in Shanghai’s soft soil foundation pit is the cement-soil gravity retaining wall. In this research, a streamlined calculation method is suggested to examine the lateral displacement of the cement-soil gravity retaining wall’s deformation features. First, the lateral pressure of the retaining wall in a nonlimit passive state is calculated by separately estimating water and soil pressure. Then, the work performed by the lateral pressure of the retaining wall and the internal energy of deformation is calculated and analyzed according to the law of energy conservation to obtain the maximum lateral displacement at the top of the retaining wall. At last, the influences of wall insertion ratio, wall width, cement mixing ratio, and soil internal friction angle on the lateral displacement of retaining wall are analyzed with finite element numerical simulation. The results of the streamlined calculations are contrasted with the measured findings when paired with engineering scenarios, which demonstrates that the predicted lateral displacement is reasonably accurate with an average error of less than 15%.

To clarify dynamic changes of organelle microstructures in Chlorella pyrenoidosa cells during photosynthetic growth with CO2 fixation, three-dimensional organelle microstructures in three growth periods of meristem, elongation and maturity were quantitatively determined and comprehensively reconstructed with focused ion beam scanning electron microscopy (FIB-SEM). The single round-pancake mitochondria in each cell split into a dumbbell and then into a circular ring, while barycenter distance of mitochondria to chloroplast and nucleus was reduced to 45.5% and 88.3% to strengthen energy transfer, respectively. The single pyrenoid consisting of a large part and another small part in each chloroplast gradually developed to a mature state in which the two parts were nearly equal in size. The nucleolus progressively became larger with euchromatin replication. The number of starch grains gradually increased, but average grain volume remained nearly unchanged.

Chemical looping combustion (CLC) plays a vital role in coal combustion which released pure CO2 in the exhaust gas with low energy consumption. Researchers have developed over 1000 oxygen carriers (OCs) to enhance the properties of OCs. This study focus on the microstructural changes of coal during CLC process which could provide the performance improvement direction for OCs. Results showed that the phenolic -OH group can easily be removed by CuO while the free -OH group and the self-associating -OH group are hard to be consumed by the lattice oxygen in CuO at 800 °C, showing good stability in CLC process. Aliphatic hydrocarbons could be consumed in the gas phase rapidly. The functional group of C=O maintains high reactivity with CuO which explains why the addition of CO2 promotes the reaction rate in coal CLC. But C=C group was nonpolar bond and hard to be consumed while the -CH2 and -CH3 group and C-O-C group showed good reactivity with CuO. Higher reaction temperature affords higher reactivity of coal CLC process. But the -OH group changed slowly at higher temperature which could because that higher temperature makes the organic big molecular of the coal char decomposed and produce more -OH group.

Background: The inner association of inflammation with voriconazole (VCZ) metabolism has not been fully investigated. We intend to investigate the effects of inflammation on liver function, VCZ trough concentration (C0), C0/dose ratio and the ratio of VCZ to VCZ-N-oxide concentration (C0/CN) in adult and elderly patients.Methods: A single-center retrospective study was conducted among patients who were treated in our hospital between January 2018 and December 2021. For each eligible patient, demographic details, medical history, laboratory parameters, procalcitonin (PCT), C reactive protein (CRP), and interleukin-6 (IL-6) were collected from the medical chart. VCZ CN, TNF-α, IL-1β, IL-8, and IL-10 concentrations were detected in blood samples.Results: A total of 356 patients were included in our study, with 195 patients in the adult cohort (0/CN ratio (CRP: r = 0.512, p < 0.001; IL-8: r = 0.476, p = 0.002). IL-6 level shallowly associated with VCZ C0/CN ratio both in adult and elderly patients (r = 0.355, p = 0.003; r = 0.386, p = 0.001). A significantly higher VCZ C0, C0/dose ratio and C0/CN ratio was observed in adult patients with severe inflammation compared with patients with moderate inflammation and no to mild inflammation, as reflected by PCT levels (p < 0.05). However, there was no significant difference observed among different inflammation degrees in elderly patients. Lower albumin (AL) and higher total bilirubin (TBIL) were observed along with the degree of inflammation in both adult and elderly patients, as reflected by CRP and PCT levels (p < 0.05).Conclusion: Inflammation may affect the metabolism of VCZ to VCZ-N-oxide both in adult and elderly patients, and decreased plasma AL levels and increased TBIL levels under inflammatory conditions may also alter VCZ metabolism.

Peridynamics (PD) is a novel nonlocal theory of continuum mechanics capable of describing crack formation and propagation without defining any fracture rules in advance. In this study, a multi-grid bond-based dual-horizon peridynamics (DH-PD) model is presented, which includes varying horizon sizes and can avoid spurious wave reflections. This model incorporates the volume correction, surface correction, and a technique of nonuniformity discretization to improve calculation accuracy and efficiency. Two benchmark problems are simulated to verify the reliability of the proposed model with the effect of the volume correction and surface correction on the computational accuracy confirmed. Two numerical examples, the fracture of an L-shaped concrete specimen and the mixed damage of a double-edged notched specimen, are simulated and analyzed. The simulation results are compared against experimental data, the numerical solution of a traditional PD model, and the output from a finite element model. The comparisons verify the calculation accuracy of the corrected DH-PD model and its advantages over some other models like the traditional PD model.

Improving the dewatering performance of sludge is a necessary advancement for collaborative sludge disposal and energy-efficient utilization in power plants. Herein, the effects of temperature changes and the addition of drying accelerators derived from agricultural and industrial waste on the drying characteristics of sewage sludge (SS) were investigated from the perspectives of drying kinetics and micromorphology. According to the results, the drying time for sludge significantly showed a clear downward trend via medium-low temperature (160 °C) thermal drying, which subsequently reduced the energy input substantially. When the drying temperature was 160 °C, the ideal addition proportions of rice husk (RH), sludge ash (SA), and coal ash (CA) comprised 15%. The addition of SA prominently boosted the drying rate constant of the original sludge by 48%. Additionally, SEM images along with the spectral dimension obtained via fractal theory explicitly clearly demonstrated that SS + SA had more loose pore channels than other mixed samples. This provided a convenient approach to ensure the evaporation and migration of moisture and thereby shorten the drying time effectively. Consequently, the addition of sludge ash as a drying accelerator can promote the deep dewatering of sludge.

To analyze the kinetic characteristics of a debris flow that occurred on 9 April 2000 in Tibet, China, a meshfree numerical method named smoothed particle hydrodynamics (SPH) is introduced, and two-dimensional and three-dimensional models are established in this work. Based on the numerical simulation, the motion process of this debris flow is reproduced, and the kinetic characteristics are analyzed combining with the field investigation data. In the kinetic analysis, the flow velocity, runout distance, deposition, and energy features are discussed. Simulation results show that the debris flow mass undergoes an acceleration stage after failure, then the kinetic energy gradually dissipates due to the friction and collision during debris flow propagation. Finally, the debris flow mass blocks the Yigong river and forms a huge dam and an extensive barrier lake. The peak velocity is calculated to be about 100 m/s, and the runout distance is approximately 8000 m. The simulation results basically match the data measured in field, thus verifying the good performance of the presented SPH model. This approach can predict hazardous areas and estimate the hazard intensity of catastrophic debris flow.

To analyse the kinetic characteristics of a rapid landslide that occurred on 9 April 2000 in Tibet, China, a meshfree numerical method named Smoothed Particle Hydrodynamics (SPH) is introduced, and two-dimensional and three-dimensional models are established in this work. Based on the numerical simulation, the landslide motion process is reproduced and the kinetic characteristics are analysed combined with the field investigation data. In the kinetic analysis, the landslide velocity, run-out distance, landslide accumulation, and energy features are discussed. Simulation results show that the landslide mass undergoes an acceleration stage after failure, then the kinetic energy dissipates gradually due to the friction and collision during the landslide propagation. Finally, the landslide mass blocks the Yigong river and forms a huge landslide dam and an extensive barrier lake. The peak velocity is calculated to be about 100 m/s, and the run-out distance is approximately 8,500 m. The simulation results basically match the data measured in field, thus verifying the good performance of the presented SPH model. This approach can provide a new way to predict hazardous areas and estimate the hazard intensity of rapid landslides.

Two groups of unsteady flows over a stationary SD7003 airfoil are studied with the large eddy simulation method. In the first group, the angle of attack (AoA) is fixed, while the freestream velocity magnitude varies harmonically with various frequencies and amplitudes. In the second group, the freestream velocity magnitude is fixed but its direction, therefore the AoA varies harmonically. Over the range of parameters considered in this study the mean lift and drag coefficients of the unsteady flows with oscillating freestream velocity magnitude are found to be nearly the same as those calculated for steady flows. However, there are significant phase shifts between the aerodynamic forces and the unsteady freestream velocity. The phase shift for drag force is larger than that for lift force, even though both increase as the frequency of freestream velocity oscillations increases. Furthermore, the computed lift amplitudes are found to be noticeably higher than those predicted by Greenberg's inviscid theory, while the lift phase shifts are in better agreement with the theory. For flows with oscillating freestream AoA, there is little change in the mean lift, while the mean drag is reduced by oscillations in AoA due to Katzmayr effect. As the frequency of oscillations in AoA increases, the phase shift for lift increases while that for drag decreases. Our results also indicate that the mean separation point moves downstream and the mean reattachment point moves upstream when the freestream velocity magnitude or the freestream flow direction oscillates with respect to the airfoil.

This study has developed a versatile nano-system with the combined advantages of photothermal effect, active tumor-targeting, temperature-sensitive drug release, and photoacoustic imaging. The nano-system consists of the core of the phase change material (PCM), the outer polypyrrole (PPY) shell and the hyaluronic acid (HA) modified in the PPY shell. The obtained composite nanoparticles (denoted as DTX/PPN@PPY@HA) were spherical with a mean diameter of about 232.7 nm. In vivo and in vitro photoacoustic imaging experiments show that DTX/PPN@PPY@HA is an effective photoacoustic contrast agent, which can be used for accurate localization of tumor region and real-time guidance of photothermal chemotherapy. DTX/PPN@PPY@HA shows good photothermal effects and temperature-sensitive drug release. In addition, cellular experiments showed that DTX/PPN@PPY@HA could be efficiently internalized into tumor cells and produce significant cytotoxicity with the help of near-infrared (NIR) laser. Furthermore, the remarkable inhibition of DTX/PPN@PPY@HA against tumor growth was achieved in 4T1 tumor-bearing mice model.

Co-combustion technology of coal and sewage sludge (SS) was encouraged and recommended in China. Previous studies most focused on its influence on combustion characteristics, migration characteristics of heavy metals in fly ash, and emission of conventional pollutants, etc., but less reported the formation characteristics of polychlorinated-ρ-dibenzodioxins and dibenzofurans (PCDD/Fs). To well reveal it, this study carried out five parallel experiments, including the pyrolysis of SS, the combustion of SS, the co-combustion of coal and SS with the proportion of 0%, 2.5% and 5%, respectively. The emission concentration of PCDD/Fs respectively increased from 0.42 ng g–1 (0.0022 ng I-TEQ g–1) to 0.54 ng g–1 (0.0030 ng I-TEQ g–1) and 1.70 ng g–1 (0.0305 ng I-TEQ g–1) with increasing blending proportion of SS. The dominant part was also changed from PCDF (0.32 ng g–1 in M-0%, 0.38 ng g–1 in M-2.5%) to PCDD (1.11 ng g–1 in M-5%). The formation concentration of PCDD/Fs in the combustion process of SS was about 0.34 ng g–1 (0.0019 ng I-TEQ g–1). In the pyrolysis process of SS, the concentration of PCDD/Fs was 0.59 ng g–1 (0.0037 ng I-TEQ g–1). The de novo synthesis should be the major formation pathway of PCDD/Fs in the co-combustion process of coal and SS. On the basis of sufficient carbon sources, the PCA analysis revealed the chlorine source (Cl) and metal catalyst (Fe) should contribute a lot on the formation of PCDD/Fs. The results paved the way for further optimization on the operation of co-combustion of coal and SS and assist in controlling the PCDD/F emission from co-combustion process.

In this paper, we report on the analysis of reverse flow in inverted U-tubes of a steam generator under natural circulation condition. The mechanism of reverse flow in inverted U-tubes of the steam generator with natural circulation is graphically analyzed by using the full-range characteristic curve of parallel U-tubes. The mathematical model and numerical calculation method for analyzing the reverse flow in inverted U-tubes of the steam generator with natural circulation have been developed. The reverse flow in an inverted U-tube steam generator of a simulated pressurized water reactor with natural circulation is analyzed. Through the calculation, the mass flow rates of normal and reverse flows in individual U-tubes are obtained. The predicted sharp drop of the fluid temperature in the inlet plenum of the steam generator due to reverse flow agrees very well with the experimental data. This indicates that the developed mathematical model and solution method can be used to correctly predict the reverse fl...

In this study, a numerical approach—the discontinuous Meshless Local Petrov-Galerkin-Eshelby Method (MLPGEM)—was adopted to simulate and measure material plasticity in an Al 7075-T651 plate. The plate was modeled in two dimensions by assemblies of small particles that interact with each other through bonding stiffness. The material plasticity of the model loaded to produce different levels of strain is evaluated with the Lamb waves of S0 mode. A tone burst at the center frequency of 200 kHz was used as excitation. Second-order nonlinear wave was extracted from the spectrogram of a signal receiving point. Tensile-driven plastic deformation and cumulative second harmonic generation of S0 mode were observed in the simulation. Simulated measurement of the acoustic nonlinearity increased monotonically with the level of tensile-driven plastic strain captured by MLPGEM, whereas achieving this state by other numerical methods is comparatively more difficult. This result indicates that the second harmonics of S0 mode can be employed to monitor and evaluate the material or structural early-stage damage induced by plasticity.

5). For better understanding of the formation and turbulent breakdown of laminar separation bubbles (LSB), both local and two-dimensional global linear stability analysis are applied to investigate the stability of a CFD time-averaged non-parallel flowfield over a SD7003 airfoil at Reynolds number 6×10 4 . The flow is found to be unstable at all wavenumbers examined. The most unstable modes from local and global stability analysis are close to each other, and the frequency of this mode is in agreement with CFD results. Spatial structures of the disturbances at most unstable modes are discussed. By applying the stability analysis, the temporal flow structures of the LSB can be examined with the most unstable modes of global stability results.