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Dynamic compaction (DC) represents a cost-effective method for reinforcing subgrade and is particularly suited to treating large-scale building subgrade. Nevertheless, the effect of DC reinforcement on high groundwater level (HGL) subgrade remains uncertain due to the lack of clarity surrounding the energy transfer mechanism of DC in HGL subgrade. In this paper, an outdoor model test of HGL subgrade was conducted based on the DC method. The temporal evolution of the internal transverse and vertical dynamic stresses in soil under different water levels, energy levels, and tamper weight conditions was monitored, and the DC mechanism of HGL subgrade was described from the perspectives of the dynamic stress waveform, peak development, and attenuation. On this basis, a novel methodology for assessing the extent of subgrade reinforcement through the utilization of impulses was put forth, thereby facilitating a more precise evaluation. The results showed that the HGL is obstructive in DC energy transfer. The peak dynamic stress, depth of impact and maximum impulse per unit area were markedly diminished when tamping the water surface. The study results also recommend that construction could expand the application range of the DC method and provide engineering suggestions for the selection of construction parameters and subsequent building construction. [ABSTRACT FROM AUTHOR]

The airport apron is a high-risk area for aircraft collisions due to its heavy operational load and high aircraft density. Currently, existing quantitative models for apron collision risk provide limited consideration and classification of risk areas. In response, this paper proposes a Petri net-based method for assessing aircraft collision risk. The method predicts the probability of aircraft reaching different areas at different times based on operational data, enabling the calculation of collision risks within the Petri net framework. This approach highlights areas with potential collision risks and provides a classification evaluation. Subsequently, aircraft path re-planning is carried out to reduce collision risks. The model simplifies the complex operations of the apron system, making the calculation process clearer. The results show that, during the mid-phase of aircraft taxiing, there is a significant deviation between the actual and ideal positions of aircraft. Areas with high taxiway occupancy are more prone to collision risks. On peak days, due to relatively high flight volumes, the frequency of collision risks is 14% higher than on regular days, with an average risk increase of 23.3%, and the risks are more concentrated. Therefore, reducing collision risks through path planning becomes more challenging. It is recommended to focus attention on areas with high taxiway occupancy during peak periods and carefully plan routes to ensure apron safety. [ABSTRACT FROM AUTHOR]

In this paper, low circumferential reciprocating load foot-scale tests were performed on two nontruncated PHC B 600 130 tubular piles with bearing nodes to characterize the damage process and morphology of the specimens and to investigate the load-carrying performance of the members. The test results reveal that under the action of tensile-bending-shear loading, the bearing concrete in the node area buckles and is damaged, the anchored reinforcement in the node area yields, the constraint is weakened, an articulation point is formed, and the node rotational capacity increases. When the embedment depth increases from 200 mm to 300 mm, the ultimate bearing capacities of the positive and negative nodes increase by 31.04% and 36.16%, respectively. A numerical simulation is used to verify the test results. Considering the four types of piles without truncated nodes, the numerical simulation is used to analyze the node-bearing capacity at different embedment depths. Finally, a preferred node type is proposed as follows: a terminal plate welded anchor bar and pipe pile core-filled longitudinal reinforcement anchored into the bearing node, with a preferred embedment depth of 250 mm. [ABSTRACT FROM AUTHOR]

The Hydrogen (H2) sensor based on palladium nanogaps (Pd NGs) offers the advantages of low detection limits and fast response times. It holds significant potential for early warning of H2 leakages. However, the preparation methods of Pd NGs for such sensors are really complex. In this study, the spray-deposition method was introduced to streamline the preparation method of Pd NGs and optimize the quantity of Pd NGs by adjusting the coverage of Pd nanoparticles (Pd NPs). The effect of different coverage of Pd NPs on the gas sensing performance of the sensor was investigated. The results revealed that sensors with lower coverage exhibited higher H2 sensitivity. The sensor exhibited a response time of 10 s at room temperature and shorten to 2 s at 100 °C in 2500 ppm H2. Furthermore, the sensor achieved a detection limit as low as 50 ppm. These findings offer a method for effectively optimizing the sensing performance of Pd NGs based H2 sensors. [ABSTRACT FROM AUTHOR]

In this study, Chromium nanoparticles (Cr NPs) were introduced as adhesion sites between Palladium (Pd) films and SiO2 substrates to enhance the sensing performance of room-temperature hydrogen (H2) sensors for lithium-ion batteries. The morphology of the Cr NPs was characterized using atomic force microscopy and scanning electron microscopy. The sensitivity, selectivity, and long-term stability were evaluated in a thermostatic bath using the four-wire method in a wide temperature range. The results showed that incorporating with dispersive Cr NPs under the Pd film as adhesion sites which significantly enhances the sensing performance of the sensor to address the issues of deformation in pure Pd films and the clamping effect in continuous Cr films as adhesion. Additionally, a circuit was developed for accurately collecting the signals of the H2 sensor. [ABSTRACT FROM AUTHOR]

Background: Lowered nicotinamide adenine dinucleotide (NAD+) levels in tumor cells drive tumor hyperprogression during immunotherapy, and its restoration activates immune cells. However, the effect of lenvatinib, a first-line treatment for unresectable hepatocellular carcinoma (HCC), on NAD+ metabolism in HCC cells, and the metabolite crosstalk between HCC and immune cells after targeting NAD+ metabolism of HCC cells remain unelucidated. Methods: Liquid chromatography-tandem mass spectrometry (LC–MS/MS) and ultra-high-performance liquid chromatography multiple reaction monitoring-mass spectrometry (UHPLC-MRM-MS) were used to detect and validate differential metabolites. RNA sequencing was used to explore mRNA expression in macrophages and HCC cells. HCC mouse models were used to validate the effects of lenvatinib on immune cells and NAD+ metabolism. The macrophage properties were elucidated using cell proliferation, apoptosis, and co-culture assays. In silico structural analysis and interaction assays were used to determine whether lenvatinib targets tet methylcytosine dioxygenase 2 (TET2). Flow cytometry was performed to assess changes in immune cells. Results: Lenvatinib targeted TET2 to synthesize and increase NAD+ levels, thereby inhibiting decomposition in HCC cells. NAD+ salvage increased lenvatinib-induced apoptosis of HCC cells. Lenvatinib also induced CD8+ T cells and M1 macrophages infiltration in vivo. And lenvatinib suppressed niacinamide, 5-Hydroxy-L-tryptophan and quinoline secretion of HCC cells, and increased hypoxanthine secretion, which contributed to proliferation, migration and polarization function of macrophages. Consequently, lenvatinib targeted NAD+ metabolism and elevated HCC-derived hypoxanthine to enhance the macrophages polarization from M2 to M1. Glycosaminoglycan binding disorder and positive regulation of cytosolic calcium ion concentration were characteristic features of the reverse polarization. Conclusions: Targeting HCC cells NAD+ metabolism by lenvatinib-TET2 pathway drives metabolite crosstalk, leading to M2 macrophages reverse polarization, thereby suppressing HCC progression. Collectively, these novel insights highlight the role of lenvatinib or its combination therapies as promising therapeutic alternatives for HCC patients with low NAD+ levels or high TET2 levels. [ABSTRACT FROM AUTHOR]

The size dependence of contact electrification (CE) for the same material particles is a common but poorly understood phenomenon. Generally, smaller particles acquire negative charges and larger particles positive charges. However, we discover that polyethylene particles can exhibit the opposite polarity under certain conditions. We demonstrate that the particle morphology, such as sphericity and surface roughness, plays a crucial role in determining the polarity, with more spherical and smoother particles being positively charged. This morphology effect can even alter the relative positions of materials in the triboelectric series. We propose a model that incorporates both the morphology and size effects to explain CE of the same material particles. The model successfully reproduces all our experimental results and predicts a nontrivial cyclic triboelectric sequence that we further confirm experimentally. This article reveals new insights into the nonequilibrium charge transfer mechanisms in CE. [ABSTRACT FROM AUTHOR]

The dynamic compaction mechanism of high-groundwater-level (HGL) foundations is still unclear, which seriously affects the engineering application of dynamic compaction in the riverbed and land reclamation. In this study, a dynamic compaction model test was established to analyze the vibration acceleration of the tamper, the soil surface, and the soil interior under different depths of groundwater level. Meanwhile, the propagation of the vibration wave was also analyzed, and the energy dissipation of dynamic compaction under the HGL foundation was studied combined with the modal damping ratio (ζ). The results showed that HGL resulted in poor foundation improvement. The main effects were the energy consumption and the friction reduction between the particles when the tamper was in contact with the water, which resulted in vibration acceleration and a sharp decrease in crater depth. The crater will not maintain its cylindrical shape, and further tamping will negatively affect the reinforcement. Vibration analysis showed that dynamic compaction results in dense soil with an increased damping ratio, but when the soil is tamped at the HGL foundation, the soil tends to oscillate, and the damping ratio decreases. In terms of energy, more than 70% of energy was dissipated directly under the tamping point of the high-groundwater-level foundation. Dynamic compaction has been extended from land foundation reinforcement to artificial reclamation foundation as an economical and environmentally friendly foundation treatment technique. The groundwater level in the coastal area is usually higher than that on land, which plays a decisive role in the success of dynamic compaction. However, there are few theoretical and experimental studies on the dynamic compaction of high-groundwater-level foundations. This paper analyzed the energy transfer and consumption of the dynamic compaction method for high-groundwater-level foundations from the perspective of vibration waves. The results showed that compared with dry sand, dynamic compaction of high-groundwater-level foundations will obviously consume reinforcement energy. Dynamic compaction causes groundwater levels to rise around the tamping point. The higher the tamping energy level, the more obvious the groundwater level rise. The results can provide a reference for expanding the treatment range of the dynamic compaction method and applying the dynamic compaction method to high groundwater foundations. [ABSTRACT FROM AUTHOR]

An important challenge in machine learning is performing with accuracy when few training samples are available from the target distribution. If a large number of training samples from a related distribution are available, transfer learning can be used to improve the performance. This paper investigates how to do transfer learning more effectively if the source and target distributions are related through a Sparse Mechanism Shift for the application of next-frame prediction. We create Sparse Mechanism Shift-TempoRal Intervened Sequences (SMS-TRIS), a benchmark to evaluate transfer learning for next-frame prediction derived from the TRIS datasets. We then propose to exploit the Sparse Mechanism Shift property of the distribution shift by disentangling the model parameters with regard to the true causal mechanisms underlying the data. We use the Causal Identifiability from TempoRal Intervened Sequences (CITRIS) model to achieve this disentanglement via causal representation learning. We show that encouraging disentanglement with the CITRIS extensions can improve performance, but their effectiveness varies depending on the dataset and backbone used. We find that it is effective only when encouraging disentanglement actually succeeds in increasing disentanglement. We also show that an alternative method designed for domain adaptation does not help, indicating the challenging nature of the SMS-TRIS benchmark. [ABSTRACT FROM AUTHOR]

A new method of microwave‐enhanced devolatilization has been proposed to solve the problem that volatiles of polyethylene particles are difficult to remove. Using water as microwave susceptor in a fixed‐bed devolatilizer, microwave heating characteristics were studied by optical fiber thermometry and infrared thermal imaging, and particle devolatilization characteristics were investigated by headspace gas chromatography. The results showed that bed temperature rose and particle devolatilization efficiency increased with heating time, moisture content, and input microwave power. The non‐uniform devolatilization at different positions existed due to the non‐uniform distribution of bed temperature in both radial and axial directions. The effective diffusion coefficient of volatiles under microwave irradiation increased with moisture content and input microwave power, and the microwave‐enhanced coefficient of water also increased with input microwave power. Microwave heating and devolatilization mechanism of moist polyethylene particles were proposed, in which the modes of mass and energy transfer were clarified. In view of the above, the feasibility of microwave‐enhanced polyethylene devolatilization has been confirmed. [ABSTRACT FROM AUTHOR]

Vibration induced by shield construction can lead to liquefaction of saturated sand. Based on FLAC3D software, a numerical model of tunnel excavation is established and sinusoidal velocity loads with different frequencies are applied to the excavation face. The pattern of the excess pore pressure ratio with frequency, as well as the dynamic response of soil mass under different frequency loads before excavation, is analyzed. When the velocity sinusoidal wave acts on the excavation surface of the shield tunnel with a single sand layer, soil liquefaction occurs. However, the ranges and locations of soil liquefaction are different at different frequencies, which proves that the vibration frequency influences the liquefaction location of the stratum. For sand-clay composite strata with liquefiable layers, the influence of frequency on the liquefaction range is different from that of a single stratum. In the frequency range of 5–30 Hz, the liquefaction area and surface subsidence decrease with an increase in vibration frequency. The research results in this study can be used as a reference in engineering practice for tunneling liquefiable strata with a shield tunneling machine. [ABSTRACT FROM AUTHOR]

The heat and mass transfer characteristics during the collision process of hydrocarbon droplets and polyethylene particles in a liquid‐containing gas–solid polyethylene fluidized bed reactor significantly affect the product quality. In this work, the mass transfer process of single‐component hydrocarbon and bi‐component hydrocarbon liquid films on the polyethylene particle surface were quantitatively characterized by a newly developed experimental approach, based on a novel synthesized hydrocarbon liquid soluble fluorescent probe for sensitive tracing of hydrocarbon liquid diffusion. It was found that the boiling point and surface tension of the liquid as well as the surface temperature of the particle are the key factors affecting the mass transfer properties of the liquid film. Marangoni convection was observed and characterized on the particle surface. The critical time for the onset of Marangoni flow is between 4 and 8 s. [ABSTRACT FROM AUTHOR]

A deep understanding of hydrodynamics and film formation characteristics is a prerequisite for the design of twin‐shaft kneaders. In this work, the hydrodynamics and film formation characteristics of a self‐cleaning twin‐shaft kneader are investigated using computational fluid dynamics method. Because of the intermeshing interaction and scratching action of the kneader rods, both bounded films and free films coexist in the kneader. Since both shafts rotate clockwise, more liquid is accumulated in the left cylinder. The liquid level of the left cylinder is higher which reduces the film formation rate of the left zone. The film formation rate in the right zone is 1.3–1.8 times that of the left zone and overlapping zone. The differences between the left and right cylinders would cause inconsistent devolatilization performances. To reduce the negative effects of asymmetric level, a static kneading rod is used to reduce the liquid level of the left zone and increase the film formation rate by 15%. We notice that adding a static kneading rod reduces the power consumption by 10%–30% compared with increasing the rotating speed to the same film formation rate. It could be an efficient method for polymer devolatilization. [ABSTRACT FROM AUTHOR]

The continuous granular flow under gravity extensively exists in chemical processes, and the dynamic behaviors of granular flow under different gas–liquid environments are investigated by synchronous slide‐type high‐speed photography. Results show that a hexagonal arrangement is observed after three‐stage densification in wet granular flow, while these structures are almost absent in the dry system. Further analysis shows that under the induction of liquid, the special cavity collapse in stage І is the pre‐condition of granular densification, and the subsequent densification in stage ІІ for the first time gives the experimental proof for the hypothesis that energy barriers exist and depend on the friction characteristics, and the cage effect in stage ІІІ provides a guarantee for the formation of a hexagonal contact network. Besides, three‐stage densification in the three‐phase system mainly occurs in the region with low gas and liquid velocities (G* < 0.716 and L* < 0.023 in this work). [ABSTRACT FROM AUTHOR]

The neural representation of concepts is a focus of many cognitive neuroscience studies. Prior works studying concept representation with neural imaging data have been largely limited to concrete concepts. The use of relatively small and constrained sets of stimuli leaves open the question of whether the findings can generalize other concepts. We share an fMRI dataset in which 11 participants thought of 672 individual concepts, including both concrete and abstract concepts. The concepts were probed using words paired with images in which the words were selected to cover a wide range of semantic categories. Furthermore, according to the componential theories of concept representation, we collected the 54 semantic features of the 672 concepts comprising sensory, motor, spatial, temporal, affective, social, and cognitive experiences by crowdsourcing annotations. The quality assessment results verify this as a high-quality neuroimaging dataset. Such a dataset is well suited to study how the brain represents different semantic features and concepts, creating the essential condition to investigate the neural representation of individual concepts. Measurement(s) Blood Oxygen Level-Dependent Functional MRI Technology Type(s) Functional Magnetic Resonance Imaging Factor Type(s) none Sample Characteristic - Organism Homo sapiens [ABSTRACT FROM AUTHOR]

The gas–liquid–solid three‐phase moving beds could supply a potential solution for multiphase reactions with catalyst easily deactivated, and the flow regimes in it were studied by optical method and pressure drop measurement. Results showed that taking the trickle flow as the initial flow regime, the flow channels were more obvious as the particle velocity increased. When the initial flow regimes were pulse flow and bubble flow respectively, the pulse‐to‐trickle and bubble‐to‐pulse flow transitions mainly occurred at moderate‐to‐high particle velocities (0.01–0.04 m s−1 under conditions used in this work). Moreover, the flow regime map in the three‐phase moving bed was constructed and shown that the region of trickle flow increased and the region of bubble flow decreased. Finally, the application of three‐phase moving beds was discussed, and it could be suitable for those reactions, which had to operate in the pulse flow, bubble flow, and transition zone. [ABSTRACT FROM AUTHOR]

In a gas–solid fluidized bed with continuous hydrocarbon liquid spray, a volatile "cloudy zone" could be formed, defined as a dynamically steady liquid‐affected zone, including droplets, wet particles, and the gas which passes through the zone. A new flow pattern with the dynamic coexistence of cloudy zone and non‐cloudy zone (gas–solid zone), is accordingly established. The temperature, particle concentration, and particle velocity fields are measured in real‐time via infrared thermography and particle imaging velocimetry, respectively. Results show that the area and range of central position of the cloudy zone illustrate a heavier fluctuant trend with the increasing velocity of liquid spray, and the main frequency of area fluctuation is close to that of the bubble rising. Moreover, the particle concentration and particle velocity in the cloudy zone are lower than those in the non‐cloudy zone, breaking the conventional symmetrical distributions of hydrodynamic parameters of particles in a gas–solid fluidized bed. [ABSTRACT FROM AUTHOR]

A screened waveguide with a 90° elbow, which had a rubber surface to reduce noise generations and a steel/air interface to block noise propagations, was designed to measure local particle movements in certain directions. In the riser of circulating fluidized bed, the noise energy only accounted for 2.1% of the total energy received by the waveguide. Besides, the radial acoustic emission energy distribution detected via the waveguide was highly consistent with the radial solid flux distribution measured by the extraction probe. Furthermore, the radial flow patterns in the riser with Geldart D particles were measured under dense phase conveying by this new method, which always demonstrated as core‐annulus flows and the transition points (r/R) increased with decreasing solid–gas ratios. [ABSTRACT FROM AUTHOR]

The bubble breakups in a jet bubbling reactor are captured using a high‐speed camera and the velocity field is measured by particle image velocimetry. Two typical breakup patterns, jet breakup and jet‐vortex breakup are observed. The breakup time interval of the jet‐vortex breakup is two orders of magnitude higher than the jet breakup. The probability of the jet‐vortex breakup and the jet breakup accounting in the total breakup events increases and decreases with the jet velocity and the mother bubble size, respectively. The bubble breakup region increases with the jet velocity. The bubble breakup frequency increases with the turbulent dissipation rate and the mother bubble size. The average number of daughter bubbles increases with the Weber number. An L‐shaped daughter bubble size distribution is observed. Empirical correlations are established for the bubble breakup frequency, the average number of daughter bubbles and daughter bubble size distribution, and fitted well with the experimental results. [ABSTRACT FROM AUTHOR]

The diffusion behavior of ethylene in polyethylene is of great importance for the polymerization and degassing of polyethylene (PE) industry. Based on the gravimetric sorption and desorption measurement approach, an intelligent gravimetric analyzer is applied to obtain the solubility and diffusion coefficients of ethylene in solid low‐density PE (LDPE) with different melt indices at 30°C to 70°C, 0 to 4 atm and in molten LDPE at 160°C to 230°C, 0 to 4 atm, respectively. Results indicate that both the solubility and diffusion coefficients of ethylene in solid LDPE are smaller than those in molten LDPE, while the dissolution enthalpy and diffusion activation energy of ethylene in solid LDPE are higher. In addition, one‐ and two‐dimensional diffusion models are built and the effects of particle size, polymer properties, and operation conditions are systematically investigated on the diffusion behaviors of ethylene in solid and molten LDPE. [ABSTRACT FROM AUTHOR]

Based on a self‐established cold‐flow experimental device, the pressure drop in a cocurrent downflow three‐phase moving bed was investigated under a wide range of gas, liquid, and solid flow rates during dynamic and steady‐state operation. The results showed that for the startup of the bed, since the first bed layer packed by fall‐falling of particles had lower voidage, it would take at least one bed volume time to make the voidage in the bed reach the steady‐state. Under steady‐state conditions, the pressure drop increased with the increase of gas and liquid mass flow rates, liquid viscosity, and decreased with the increase of solid flow rate. Furthermore, it was found that the liquid distribution became more uniform due to particle movement. The experimental data obtained in this study was used to develop a correlation to predict the pressure drop in a three‐phase moving bed with an average relative error of 9.32%. [ABSTRACT FROM AUTHOR]

Nowadays, the droplet–particle collision characteristics in the gas‐phase ethylene polymerization process are still unclear. The high‐speed photography and a quasi‐circle imaging approach are employed to study the collision interaction characteristics between liquid droplets and polyethylene particles. The liquid film evolution is studied through variations of the film thickness on the particle north pole, the dynamic contact angle, center angle and film thickness at the maximum extension. Results have found that for n‐hexane the threshold temperature of the recoil happening increases with increasing initial Weber number, but for 1‐hexene it is stable. Over 70°C evaporation and splash occurs immediately. Under low Weber numbers, the water droplet stays for damping oscillations, the reference stable height of which is linearly related to temperatures. Moreover, three regimes of film thickness variation with time are identified and mathematically described, while Regime 3 characteristics are found strongly dependent on the liquid species, Weber number, and particle temperature. [ABSTRACT FROM AUTHOR]

Electrostatic potential in the multizone circulating fluidized bed (CFB) reactor for polypropylene is measured even larger than 1,000 V. In this article, electrostatic effects on hydrodynamics in the riser of CFBs were studied via experiment and computational fluid dynamic simulation. Experimental results showed electrostatics increased solids holdup in the riser for more than 20% in fast fluidization. Using measured charge densities as electrostatic model parameters, electrostatic effects were simulated by two‐fluid model coupled with electrostatics accurately. The relative deviation between measured and simulated solids holdup was 3.53% at 5.68 m/s, which was the first time that this mode was verified quantitatively. Further analysis of simulation results demonstrated the mechanism of electrostatic effects was that the electrostatic forces increased the radial particle velocity and induced particle accumulation near the wall, leading to the increase of solids holdup. These electrostatic effects are more significant in the dense‐phase region, which require special care. [ABSTRACT FROM AUTHOR]

Summary: The effects of polysaccharides, theaflavins, thearubigins and theabrownin fractions of Zijuan tea on α‐glucosidase and blood glucose level and intolerance of hyperglycaemic mice were evaluated. The polysaccharides or theaflavins fraction exhibited greater inhibition rate of α‐glucosidase than acarbose positive control, thearubigins fraction or theabrownin fraction. The four fractions were delivered to the treatment mice through oval gavage each day for 15 days. The mice in polysaccharides and theaflavins high‐ and low‐dose and theabrownin high‐dose treatments significantly lowered their blood glucose levels while all the treatment mice gained body weight. The mice in polysaccharides, theaflavins and theabrownin high‐ and low‐dose treatments had greater glucose tolerance as well. Thus, the theaflavins and polysaccharides fractions of Zijuan tea effectively moderated the complications of hyperglycaemic mice. The lower effectiveness of thearubigins and theabrownin fractions may be caused by the highly polymerised polyphenolics which decreased their accessibility to α‐glucosidase and digestibility in mice. [ABSTRACT FROM AUTHOR]

Anti-biofilm assay guided fractionation of the marine sponge Stylissa massa revealed the butanol soluble fraction that was possessing the inhibitory activity toward the biofilm formation of bacterium E. coli. Chromatographic separation of the bioactive fraction resulted in the isolation of 32 bromopyrrole alkaloids, including six new alkaloids, named stylisines A-F (1-6). The structures of new alkaloids were established by comprehensive analyses of the two-dimensional (2D) NMR (COSY, HMQC, and HMBC) and the high resolution electrospray ionization mass spectroscopy (HRESIMS) data, while the absolute configurations were determined by the X-ray diffraction and the electronic circular dichroism (ECD) data. Bioassay results indicated that phakellin-based alkaloids, including dibromoisophakellin and dibromophakellin, significantly reduced the biofilm formation of the bacterium E. coli. Present work provided a group of new natural scaffolds for the inhibitory effects against the biofilm formation of E. coli. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1038/s41597-022-01840-2. The Acknowledgements section was missing from this article and should have read 'This work is supported by Youth Innovation Promotion Association CAS.'. [Extracted from the article]

ABSTRACT The solubility of hydrogen (H2), ethylene (C2H4), 1-hexene (C6H12), and the mixture of C2H4/1-C6H12 in semicrystalline polyethylene (PE) films is measured using an intelligent gravimetric analyzer (IGA) in combination with prediction equations. For the pure-component sorption in PE, the solubility of C2H4 and 1-C6H12 decreases with the temperature, while that of H2 exhibits an opposite variation tendency in the temperature range under test. For the C2H4/1-C6H12 mixture, the co-solubility is almost 10% smaller than the sum of the pure-component solubility. 1-C6H12 acts as a co-solvent and C2H4 an antisolvent. Moreover, good consistency has been achieved between the measured data and the prediction results from the Sanchez-Lacombe EOS model, demonstrating the reliability of the measurement approach employed in this work. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44507. [ABSTRACT FROM AUTHOR]

ABSTRACT The self-diffusion coefficients of C6-C16 long-chain α-olefins and their mixtures in semi-crystalline polyethylene were measured through the pulsed field gradient nuclear magnetic resonance (PFG-NMR). The effects of chain length, polyethylene (PE) type, and co-monomer type in PE on the diffusion coefficients were investigated. Moreover, the influence of halohydrocarbon, cycloalkanes, and arene solvents on the diffusion coefficients of C12 α-olefin in PE was characterized. The results have demonstrated that the diffusion coefficient of the single-component α-olefin in PE decreases exponentially with the increase of the carbon number of α-olefin, and the crystallinity and crystal morphology of PE play a more important role than the co-monomer type in determining the diffusion coefficients of α-olefins. In addition, the apparent diffusion coefficients were used to represent the diffusion behaviors of the α-olefin mixtures in PE. Owing to the presence of other hydrocarbon solvents, namely trichloromethane, cyclohexane, and benzene, the diffusion coefficients of C12 long-chain α-olefin in PE are significantly enhanced, and such promoting effect of the hydrocarbon solvents in polyolefin elastomer (POE) is much stronger than those in high-density polyethylene (HDPE) and linear low-density polyethylene (LLDPE). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44143. [ABSTRACT FROM AUTHOR]

A correction to the article "CFD Modeling of Electrostatic Forces in Gas-Solid Fluidized Beds" that was published in the 2010 issue presented which discusses a methodology for considering the impacts of electrostatics on gas-solid fluidized beds by Euler-Euler approach.

Limited by harsh reaction conditions, the activation and utilization of methane were regarded as holy grail reaction. Co-reaction with methanol, successfully realizing mild conversion below 450 °C, provides practical strategies for methane conversion on metal-loaded ZSM-5 zeolites, especially for highly efficient Zn loaded ones. However, Zn species, regarded as active acid sites on the zeolite, have not been sufficiently studied. In this paper, Zn-loaded ZSM-5 zeolite was prepared, and Zn was modified by capacity, loading strategy, and treating atmosphere. Apparent methane conversion achieves 15.3% for 1.0Zn/Z-H2 (16.8% as calculated net conversion) with a significantly reduced loading of 1.0 wt.% against deactivation, which is among the best within related zeolite materials. Besides, compared to the MTA reaction, the addition of methane promotes the high-valued aromatic production from 49.4% to 54.8%, and inhibits the C10+ production from 7.8% to 3.6%. Notably, Zn2+ is found to be another active site different from the reported ZnOH+. Medium strong acid sites are proved to be beneficial for methane activation. This work provides suggestions for the modification of the Zn active site, in order to prepare highly efficient catalysts for methane activation and BTX production in co-reaction with methanol. [ABSTRACT FROM AUTHOR]

Background: Radioresistance is the major obstacle in radiation therapy (RT) for hepatocellular carcinoma (HCC). Dysregulation of DNA damage response (DDR), which includes DNA repair and cell cycle checkpoints activation, leads to radioresistance and limits radiotherapy efficacy in HCC patients. However, the underlying mechanism have not been clearly understood. Methods: We obtained 7 pairs of HCC tissues and corresponding non-tumor tissues, and UBE2T was identified as one of the most upregulated genes. The radioresistant role of UBE2T was examined by colony formation assays in vitro and xenograft tumor models in vivo. Comet assay, cell cycle flow cytometry and γH2AX foci measurement were used to investigate the mechanism by which UBE2T mediating DDR. Chromatin fractionation and immunofluorescence staining were used to assess cell cycle checkpoint kinase 1(CHK1) activation. Finally, we analyzed clinical data from HCC patients to verify the function of UBE2T. Results: Here, we found that ubiquitin-conjugating enzyme E2T (UBE2T) was upregulated in HCC tissues, and the HCC patients with higher UBE2T levels exhibited poorer outcomes. Functional studies indicated that UBE2T increased HCC radioresistance in vitro and in vivo. Mechanistically, UBE2T-RNF8, was identified as the E2-E3 pair, physically bonded with and monoubiquitinated histone variant H2AX/γH2AX upon radiation exposure. UBE2T-regulated H2AX/γH2AX monoubiquitination facilitated phosphorylation of CHK1 for activation and CHK1 release from the chromatin to cytosol for degradation. The interruption of UBE2T-mediated monoubiquitination on H2AX/γH2AX, including E2-enzyme-deficient mutation (C86A) of UBE2T and monoubiquitination-site-deficient mutation (K119/120R) of H2AX, cannot effectively activate CHK1. Moreover, genetical and pharmacological inhibition of CHK1 impaired the radioresistant role of UBE2T in HCC. Furthermore, clinical data suggested that the HCC patients with higher UBE2T levels exhibited worse response to radiotherapy. Conclusion: Our results revealed a novel role of UBE2T-mediated H2AX/γH2AX monoubiquitination on facilitating cell cycle arrest activation to provide sufficient time for radiation-induced DNA repair, thus conferring HCC radioresistance. This study indicated that disrupting UBE2T-H2AX-CHK1 pathway maybe a promising potential strategy to overcome HCC radioresistance. [ABSTRACT FROM AUTHOR]

An image analysis method was developed based on deep‐learning algorithms to extract phase fractions quantitatively in a rectangular trickle bed, and the average identification error was lower than 5%. Furthermore, the flow regime transition in the trickle bed was studied. In trickle‐to‐pulse flow transition, the trickle flow could be further classified into the stable trickle flow and accelerated one. The SD of liquid fractions and the peak width at half‐height of the probability density curve of liquid fractions were close to zero in stable trickle flow, increased rapidly in accelerated trickle flow, and remained approximately constant in pulse flow. In bubble‐to‐pulse flow transition, dispersed bubbles in bubble flow induced the outliers outside the upper boundary of the boxplot of gas fraction, while alternative appearance of gas‐rich zone and liquid‐rich zone in pulse flow induced outliers outside both the upper and lower boundaries of the boxplot of gas fraction. [ABSTRACT FROM AUTHOR]

This work investigated the effect of inclination angle on the minimum conveying velocity and the underlying mechanisms. Results showed that the pressure drop increased first and then decreased with the increasing inclination angle at the same mass flux and superficial gas velocity. The changing trend of minimum conveying velocity (umin) and the pressure drop near it can be divided into two types by taking 45° as the boundary, which was consistent with the difference in flow regimes near umin at different inclination angles based on results of high‐speed photography and acoustic emission detection. Furthermore, the pressure drop was decomposed to investigate the underlying mechanism of the changing trend of umin. Results showed that the changing trend of umin was closely related to the particle velocity and the particle velocity obtained by high‐speed photography was in good agreement with the theoretical analysis. [ABSTRACT FROM AUTHOR]

Three gas–liquid dispersion states including flooding, loading, and complete dispersion are observed sequentially in a jet bubbling reactor with an increase of the liquid jet velocity at the nozzle outlet (uj). The gas–liquid dispersion states are identified through the slope (k) of the curve of fluctuation distribution index (FI) versus uj as follows: (a) under the flooding, k = 0; (b) under the loading, k > 0; (c) under the complete dispersion, k < 0. In particular, the uj at the transition points from flooding to loading and from loading to complete dispersion are referred to flooding jet velocity (ujf, the transition point between k = 0 and k > 0) and complete dispersion jet velocity (ujcd, the transition point from k > 0 to k < 0), respectively. The average relative deviations of the uj at the transition points obtained through the acoustic emission measurement and visual observation are less than 5%. [ABSTRACT FROM AUTHOR]

Background: Sorafenib is the first-line treatment for advanced-stage hepatocellular carcinoma (HCC). Several studies have shown that the up-regulation of β-catenin plays a role in sorafenib resistance in HCC; however, the mechanism associated with this phenomenon remains elusive. Methods: Western blotting, flow cytometry, and an evaluation of IC50 values were used to confirm the role of β-catenin in HCC sorafenib resistance. Immunoprecipitation and western blotting were then performed to identify regulatory interactions between β-catenin and Nek2. Further, western blotting, flow cytometry, and an in vivo xenograft model were used to evaluate the function of Nek2 in HCC sorafenib resistance, whereas rescue experiments were performed to confirm that Nek2 induces sorafenib resistance via β-catenin. Finally, western blotting and immunohistochemistry were used to evaluate the expression level of Nek2 in paired HCC and non-tumor tissues. Results: We showed that β-catenin could suppress sorafenib-induced apoptosis and cell growth inhibition in HCC cell lines. By screening β-catenin-interacting proteins, we found that Nek2 could bind β-catenin in sorafenib-treated HCC cell lines. Our results also showed that Nek2 stabilizes β-catenin and promotes its translocation to the nucleus, consequently activating the transcription of downstream target genes. We further confirmed that Nek2 could induce sorafenib resistance in HCC cell lines, and that β-catenin was the key element involved in this process. Further, a xenograft tumor model showed that Nek2 knockdown could improve the anti-tumor effect of sorafenib, whereas an analysis of tumor proteins showed that Nek2 regulates β-catenin protein levels and its nuclear translocation in vivo. In addition, Nek2 was found to be up-regulated in HCC tissue, and especially in advanced-stage disease. Conclusions: Our study proves that Nek2 induces HCC sorafenib resistance via β-catenin and suggests a novel therapeutic strategy to improve the anti-tumor effects of sorafenib in HCC. [ABSTRACT FROM AUTHOR]

The bubble swarm trajectory in the jet bubbling reactor is measured through the bubble image velocimetry (BIV) technique. The result shows that the bubble swarm rises straightly when the jet Reynolds number is lower than 7,000. However, when the jet Reynolds number exceeds 14,000, the bubble swarm exhibits vortex‐like motion, and the bubble vortices oscillate periodically. The oscillating frequency of bubble vortices under the gas bubbling condition is lower than the flapping frequency of pure liquid jet. Moreover, the moving region and oscillating frequency of bubble vortices increase with the jet Reynolds number. The superficial gas velocity has little effect on the bubble swarm trajectory and the oscillating frequency. An empirical correlation between the oscillating frequency of bubble vortices and the jet Reynolds number is built based on the simple harmonic vibration theory. [ABSTRACT FROM AUTHOR]

This work investigated flow regimes identification in horizontal pneumatic conveying from the scope of particle motions based on acoustic emission detection. Results showed that the variation of acoustic energy and acoustic energy fraction could be used to identify the transition between suspension flow and stratified flow. Near the transition point, the acoustic energy was maximum, and the energy fraction of particle‐wall collision mutated at high mass fluxes. Furthermore, the fluctuation distribution index (FI) was constructed learning from the concept of polymer molecular weight distribution index, and the "circumferential fluctuation difference (D)" was defined. Based on this, new identification criteria and flow regime diagram were established. In suspension flow, D >0. In stratified flow, D <0. While in slug flow, D ≈ 0. According to these criteria, flow regimes can be identified independently of changing trends of measurement parameters. The universality of above criteria was further verified under different operating conditions. [ABSTRACT FROM AUTHOR]