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Capturing dibutyl phthalate (DBP) impurities from transformer oils and purifying them is crucial for maintaining long-term sustainable transformer operation. Furthermore, this process significantly reduces the generation of waste from aged transformer oils, thereby contributing to environmental protection and sustainable development. In this study, various metal ion-modified wood activated carbons (ACs) were prepared using the wet impregnation method. The adsorption isotherms and adsorption kinetics studies reveal that Fe/AC exhibits a significant enhancement of more than 40% in DBP adsorption capacity compared to the original AC. Consequently, Fe/AC is the material with the highest adsorption capacity for DBP in transformer oils up to now. Furthermore, the desorption activation energy of DBP on Fe/AC was 46.623 kJ/mol, 1.73 times higher than original AC. Ultimately, the adsorption mechanism was explained using the Hard-Soft-Acid-Base (HSAB) principle, which demonstrated a stronger interaction between hard base DBP and Fe/AC due to the hard acidic nature of Fe3+ and therefore a higher capture capacity of DBP by Fe/AC. The simplified preparation method and enhanced adsorption capacity of the modified Fe/AC make it an efficient and cost-effective approach to ensure reliable and sustained transformer operation, while also minimizing the generation of waste transformer oils. • High-performance DBP adsorbent achieved through Fe3+ impregnation on AC. • The loading of Fe resulted in a 40% increase in the DBP adsorption capacity. • Fe/AC exhibits nearly twice the DBP adsorption capacity of γ-Al 2 O 3. • The loaded Fe3+ as hard acid improved the adsorption capacity of AC on hard base DBP. [ABSTRACT FROM AUTHOR]

An in-depth study of the chemical kinetic mechanism of biodiesels can facilitate accurate prediction of engine combustion and emission characteristics. Surrogate fuel is a feasible method for simulating the combustion chemistry of real biodiesel. Methyl myristate (MMY), one of the main components and a widely used surrogate for biodiesel, was investigated for the autoignition characteristics using a newly heated rapid compression machine (RCM). In this work, the ignition delay times (IDTs) of MMY were measured at compressed pressures of 10/15/20/30 bar with compressed temperatures ranging from 700 K to 900 K, and equivalence ratios varying from 0.3 to 1.25. The experimental observation successfully captured a typical negative temperature coefficient (NTC) phenomenon of IDT. The present experiment is the first one to measure the IDTs of MMY in a RCM, while also marking the first instance of observing the NTC phenomenon in macromolecular fatty acid methyl esters above C10. Besides, a skeletal model for methyl myristate has been developed based on the idea of decoupling methodology. In terms of fuel-dependent reactions, the kinetic model is divided into two parts: high-temperature reactions and low-temperature chain branching reactions. Combined with the experimental and simulation results, the dependence of the IDT of methyl myristate on compressed temperature, compressed pressure, equivalence ratio, and oxygen mole fraction at low-to-intermediate temperature was systematically investigated. The simulation results show that the developed skeletal model captures the ignition delay times well at low-to-intermediate temperatures and accurately predicts both the NTC phenomenon and the corresponding temperature range. Based on this, the key reactions in the combustion of MMY under different conditions were elucidated through sensitivity analysis. Ultimately, the model validation was conducted against the high-temperature IDT data from the literature. The chemical kinetic models of various biodiesels are essential for simulating the working process of internal combustion engines and accurately predicting the combustion and emission characteristics. Among these, the autoignition characteristic is one of the most important parameters for model validation. Besides, the carbon chain length of methyl myristate closely resembles that of real biodiesels, making it an ideal surrogate fuel for biodiesels. In this study, the IDTs of MMY were measured for the first time at low-to-intermediate temperatures in a heated RCM, thereby experimentally confirming the NTC phenomenon of methyl myristate. Additionally, a skeletal model of MMY was developed based on the idea of decoupling methodology, which can accurately predict the autoignition characteristics of MMY at low-to-intermediate temperatures. The simulated values demonstrate good agreement with experimental data. Overall, the present study provides an IDT database for the development and validation of the methyl myristate mechanism. [ABSTRACT FROM AUTHOR]

Post-stroke depression (PSD) is a serious neuropsychiatric complication post stroke and leads to cognitive deficits. This study was conducted to explore the molecular mechanism of hypoxia-inducible factor-1α (HIF-1A) in cognitive dysfunction in rats with PSD. The rat model of PSD was established by middle cerebral artery occlusion, followed by 3 weeks of treatment with chronic unpredictable mild stress. The levels of miR-582–5p, HIF-1A, and neighbor of Brca1 gene (NBR1) in brain tissues were determined using RT-qPCR. The behaviors and cognitive capacity of rats were evaluated by various behavioral tests. PSD rats were injected with HIF-1A/miR-582–5p lowexpression vectors or NBR1 overexpression vectors via stereotactic method. The binding of HIF-1A to NBR1 or miR-582–5p was analyzed by chromatin immunoprecipitation and dual-luciferase assay. HIF-1A and NBR1 were highly expressed while miR-582–5p was poorly expressed in the brain of PSD rats. HIF-1A inhibition alleviated cognitive dysfunction of PSD rats. miR-582–5p was the upstream miRNA of HIF-1A, and HIF-1A specifically interacted with the NBR1 promoter to enhance NBR1 expression. miR-582–5p downregulation and NBR1 upregulation reversed the alleviative role of HIF-1A inhibition in cognitive dysfunction of PSD rats. In summary, HIF-1A inhibition may be a therapeutic target for cognitive dysfunction post PSD. [ABSTRACT FROM AUTHOR]

• The effects of ammonia enrichment on combustion instability are examined. • The ammonia concentration is critical in determining instability characteristics. • Primary acoustic modes change with an increasing ammonia proportion. • Flame and flow dynamics are examined to understand different instability modes. • The change in convective time delay is a key element for mode transitions. Ammonia (NH 3) has recently emerged as a promising carbon-free energy carrier. Further development and application of NH 3 as fuel in the gas turbine industry can significantly reduce the emissions of carbon dioxide (CO 2) and contribute to the achievement of a carbon–neutral society. This study experimentally examined the thermoacoustic instability characteristics of a laboratory-scaled lean premixed gas turbine model combustor operated with different NH 3 blending ratios with methane (CH 4). Experiments conducted under a wide range of inlet velocities and equivalence ratios suggest that NH 3 concentration is critical in determining the characteristics of the instability. Specifically, when the NH 3 proportion is less than 50 %, the addition of NH 3 causes a mode transition of the instability. However, when the content of NH 3 is greater than 50 %, it is shown that the instabilities are suppressed, indicating that the addition of a certain amount of NH 3 can enhance the stability of CH 4 flames. Additional analysis of flame dynamics reveals that the introduction of NH 3 causes the lengthening of the flame front and weakens heat release rate fluctuations in the flame root regions. Further Proper Orthogonal Decomposition (POD) analysis of the flow field shows that the instability modes are strongly coupled with periodic vortex motions of the flow dynamics along the shear layers. Finally, the mode shifting phenomena is successfully predicted by low-order thermoacoustic network modeling. It is suggested that the change in convective time delay caused by NH 3 addition is responsible for such transitions. [ABSTRACT FROM AUTHOR]

[Display omitted] • C 2 H 4 /C 2 H 6 separation was studied using highly permeable ZIF-8 membranes. • The membrane temperatures were varied from −30 to 100 °C for separation. • A high C 2 H 4 permeance of 8.1 × 10−7 mol/(m2·s·Pa) was observed at −30 °C. Ethylene/ethane separation is a critical and energy-consuming process in the chemical industry due to the similar properties of the compounds and the great need of ethylene for e.g., polymer production. Many materials have been studied for their implementation as membranes as an energetically favorable alternative to conventional distillation and adsorption processes. Metal-organic frameworks (MOF) have revealed promising properties as highly permeable and selective membranes. Among the most studied and promising MOF candidates is ZIF-8, known for its thermal stability and small pores connected by narrow-sized windows. In this work, we present an analysis of the influence of parameters such as temperature, feed pressure and feed flowrate on the separation of ethylene/ethane through a thin ZIF-8/alumina disc membrane. We observed that the temperature has a significant effect on the separation. The ethylene permeance increased with decreased temperature and reached 8.1 × 10−7 mol/(m2·s·Pa) at −30 °C. At this temperature, the ethylene/ethane selectivity was 2.5. The study concluded with a considerable enhancement of the permeance of ZIF-8 membranes for ethylene/ethane separations, while maintaining a good selectivity compared to the reported values in the literature. The results have important implications for the development of more cost-effective and energy-efficient membrane-based separation technologies for ethylene purification. [ABSTRACT FROM AUTHOR]

The valence of tin is the critical factor affecting the photocatalytic performance of TiO 2 when using tin as dopant. Sn4+ acts as the intermediate step for the electron transfer from Ti4+ to Sn4+ and then to the adjacent Pt, while Sn2+ plays as the defect site for carrier recombination. The intermediate step permit a long carrier lifetime, and enable the electron transfer to the surface adsorbed O 2 to form massive superoxide radical. Function of tin doping, light illumination and Pt loading are clarified. [Display omitted] • The Sn6 achieved a high hydrogen production efficiency of 39.4 mmol·h-1·g-1. • Sn4+ dopingcan promote electron transfer, while Sn2+ doping causes carrier recombination. • The intermediate step on Sn4+ site between Ti4+ and Pt leads to a longer carrier lifetime. • Function of tin doping, light illumination and Pt loading are clarified. Hydrogen production has been considered as the most promising approach for obtaining sustainable and clean energy source. Modification of TiO 2 photocatalyst with the aim of enhancing the photocatalytic efficiency has always been the top importance. In this work, Tin ions have been used as dopant to adjust the crystal phase and to improve the catalytic performance of TiO 2. The results showed that Sn4+ doping transferred the mixed phase TiO 2 photocatalyst into single rutile phase TiO 2 and increased the water splitting efficiency. Photoluminescence, X-ray photoelectron spectroscopy and UV–vis spectrometer characterization suggested that charge transfer between Ti4+ and Sn4+ is the key reason for the suppression of carrier recombination and the improvement of the photocatalytic efficiency. Sn2+ doping did not adjust the rutile/anatase mix phase formation considerably, charge transfer from Ti4+ to Sn4+ is also proved to be the reason for the slightly enhanced water splitting efficiency. This work suggests that the ion valence of tin is the critical factor affecting the photocatalytic performance of TiO 2. [ABSTRACT FROM AUTHOR]

• A novel skeletal multi-component kinetic model with heavy compounds. • Construct the model with chemical lumping and skeletal reduction methods. • Optimize the original model automatically using genetic algorithm (GA). • Validation for various data of pure components, mixtures, and real diesel. Towards high-fidelity combustion chemistry modeling of real diesel fuel, this study aims to construct a skeletal multi-component kinetic model with higher accuracy and heavy hydrocarbons (n -hexadecane, iso -cetane, n -octadecane, α -methylnaphthalene, decalin), which is feasible for engine computational fluid dynamics (CFD) applications. The developed skeletal model with 220 species and 1109 reactions is composed of lumped fuel-specific sub-mechanisms and a skeletal C 0 –C 3 core mechanism derived from the well-validated detailed NUIGMech 1.1 mechanism. Chemical lumping integrated with skeletal reduction methods and reaction pathway analysis is used to develop compact fuel-molecule sub-models. Ignition delay and species concentration are then taken as targets simultaneously to optimize the original model automatically using genetic algorithm (GA) within given parameter ranges. Eventually, the optimized kinetic model is validated against various experimental results of pure components, their mixtures and real diesel fuels, including ignition delay times in both shock tubes and rapid compression machines, species concentration profiles in jet-stirred reactors, and laminar flame speeds in the counterflow configurations as well as actual engine data. In addition, it should be noted that due to the absence of test data on pure n -octadecane, the sub-model of n -octadecane is not directly validated in this work, but compared with measurements of real diesel. Overall, the simulation results are in good agreement with experiments under a wide range of engine-like conditions, suggesting that the present skeletal multi-component mechanism can be applied to mimic autoignition and oxidation of actual diesel. As such, this will provide a more accurate and robust combustion model for the development and optimization of advanced engines with high efficiency and ultra-low emissions. [ABSTRACT FROM AUTHOR]

[Display omitted] • M(AIP)(BPY) 0.5 (M = Co, Ni, and Zn) showed efficient C 3 H 6 /C 3 H 8 separation. • The separation mechanism was based on the thermodynamic-kinetic synergetic effect. • Ni(AIP)(BPY) 0.5 had the highest C 3 H 6 /C 3 H 8 uptake ratio of 4.26 at 298 K and 1 bar. Efficient adsorption separation of propylene (C 3 H 6) and propane (C 3 H 8) can largely lower the energy consumption compared to the current energy-intensive cryogenic distillation. Herein, we report an isoreticular family of pillar-layer metal–organic frameworks (MOFs), M(AIP)(BPY) 0.5 (M = Co, Ni, and Zn), for efficient C 3 H 6 /C 3 H 8 separation by simultaneously exploiting thermodynamic and kinetic effects, circumventing disadvantages of each separation mechanism. The three MOFs feature an open metal site for each metal node and uniform but narrow one-dimensional (1D) channels, offering strong binding sites toward C 3 H 6 via π-complexations while obstructing the diffusion of bulkier C 3 H 8. The Ni-MOF shows the best separation performance based on the highest thermodynamic and kinetic C 3 H 6 /C 3 H 8 selectivities, further verified by computational simulations. Ni(AIP)(BPY) 0.5 has a moderate C 3 H 6 uptake of 1.94 mmol/g but a remarkably high C 3 H 6 /C 3 H 8 uptake ratio of 4.26 at 298 K and 1 bar. Efficient C 3 H 6 /C 3 H 8 separation, good recyclability, moisture and water stability of Ni(AIP)(BPY) 0.5 are confirmed. [ABSTRACT FROM AUTHOR]

• Fuel components' variation doesn't remarkably affect VOC compositions' proportions although it affects total VOC obviously. • Olefins and alkynes contribute most to OFP followed by aromatics and aldehydes. • More short chain i-paraffins and less branch chained cyclohexane in gasoline potentially help to reduce OFP of VOC. In this paper, effects of different components in gasoline fuel on GDI engine emission characteristics were investigated. To simplify this investigation, model fuel CDTRF (composed of n-heptane, iso -pentane, diisobutylene, cyclohexane and toluene) instead of real gasoline fuel were used. To see how components of gasoline fuel affect engine performances, iso -pentane, diisobutylene, cyclohexane or toluene in CDTRF was substituted by other iso -alkanes, olefins, naphthenes and aromatics for comparative researches. N-heptane fraction is varied to balance fuel octane number. It is found that variation of fuel components obviously affect engine regulated and unregulated emissions. While, such effects vary when engine operation condition varies and are more distinct under lower engine speed or load conditions. Fuel components affect engine emission not just simply via chemical manner, but also through accompanying thermal-power process (cylinder pressure and temperature history). Thus variation of fuel components remarkably affects engine NOx emission. Alkanes, olefins and alkynes, aromatics contribute most to VOC emission followed by aldehydes. While, proportion of alcohols in VOC is negligible. However, variation of fuel components does not remarkably affect the proportion of alkanes, olefins and alkynes, aromatics as well as aldehydes in VOC although it affects total VOC emission obviously. Olefins and alkynes contribute most to OFP followed by aromatics and aldehydes. The contribution of alkanes is relatively low although it takes significant proportion in VOC. While, variation of fuel components remarkably affects total OFP of VOC though it does not obviously affect OFP composition. According to the results, it is hinted that more short chain i-paraffins and less branch chained cyclohexane in gasoline fuel would potentially help to reduce OFP of VOC. [ABSTRACT FROM AUTHOR]

• The large-scale synthesis of H 4 abtc (180 g scale) and Y-abtc (100 g scale) in high yields. • Breakthrough experiments on binary mixtures of propane/propylene at the 100 g scale. • Polymer grade propylene purity achieved using Y-abtc at 100 g scale. • Retained performance of Y-abtc at large scale demonstrating its potential for real world applications. Olefin/Paraffin separation, especially propylene purification from propane, is of extreme commercial importance as it produces chemical feedstock for synthetic plastics such as polypropylene. As an alternative to cryogenic distillation commonly used to purify these mixtures, the use of solid porous materials for adsorptive separation offers a more energetically efficient route. Metal-Organic Frameworks (MOFs) have shown great promise as adsorptive separation candidates in recent years. However, reports of these materials for the purification of C3 hydrocarbons exclusively provide insight of their performance in small scale laboratory settings. Single component isotherms and breakthrough curves are typically tested in the milligrams to gram scale. Herein, we present a scale-up, one-pot synthesis of a robust MOF with high propylene/propane selectivity. The organic linker 3,3′,5,5′-azobenzene-tetracarboxylic acid (H 4 abtc) and its yttrium-based MOF, Y-abtc, are both synthesized at the hundred-gram scale. Furthermore, we perform large-scale breakthrough experiments at the same scale. Our results show that Y-abtc samples synthesized from the one-pot 100 g scale reactions retain high crystallinity and size-exclusion based mechanism for the separation of propane/propylene mixtures. The same polymer-grade purity of propylene (>99.5%) is achieved as in the case of small scale (∼1 g) experiments. [ABSTRACT FROM AUTHOR]

Direct ink writing (DIW) provides a new way to mould ceramic parts. When a single screw extruder is used to extrude SiC slurry, the deposits caused by low viscosity and the agglomerations resulting from the nonuniform mixing, form the obstacles in the channel, which affect the normal flow of the slurry, theoretical outlet velocity, and interaction with other printing parameters. Therefore, it is necessary to study the mechanism responsible for the effects of the obstacles on the flow. The obstacles are always irregular, which makes it difficult to directly analyse them. Irregular geometries are always composed of linear and/or arcuate elements; therefore, the obstacles can be simplified into regular geometries. In the present work, linear elements are analysed first. Then, an improved MRT LBM (multiple relaxation time lattice Boltzmann method) with a pseudo external force is proposed for the flow analysis. The improved MRT LBM is combined with rheological test data to investigate cases with two obstacles, and the results are applied to reveal the general mechanism in cases with multiple obstacles. The results show that the angles, sizes, and positions of the obstacles are three important factors influencing the flow. To obtain a stable and controllable slurry flow, it is recommended that the first angle θ 1 be an acute angle. In addition, the number of obstacles should be minimized, and the position of the last obstacle should be far away from the outlet. [ABSTRACT FROM AUTHOR]

To assess the MRI performance in differentiating pancreatic ductal adenocarcinomas (PDACs), from solid pseudopapillary neoplasms (SPNs) and pancreatic neuroendocrine tumors (PNETs) using non-gaussian diffusion-weighted imaging models. This was a retrospective study of patients diagnosed with PDACs (01/2015–06/2019) or with PNETs or SPNs diagnosed (01/2011–12/2019) at our hospital. The lesions were randomized 1:1 to the primary and validation cohorts. The regions of interest (ROIs) were manually drawn on each slice at DWI (b = 1500 s/mm2) from 3 T MRI. D (diffusion coefficient), D* (pseudodiffusion coefficient), f (perfusion fraction), distributed diffusion coefficient (DDC), α (diffusion heterogeneity index), mean diffusivity (MD) and mean kurtosis (MK) were obtained. The parameters with largest performance for differentiation were used to establish a diagnostic model. There were 148, 56, and 60 patients with PDAC, PNET, and SPN, respectively. For differentiating PDACs from SPNs, f and MK values were used to establish a diagnostic model with areas under the receiver operating characteristic curves (AUCs) of 0.92 and 0.89 in the primary and validation groups, respectively. For distinguishing PDACs from PNETs, α and MK values were used to establish a diagnostic model with AUCs of 0.87 and 0.86 in the primary and validation groups, respectively. The accuracy rate of the subjective evaluation with the assistance of non-gaussian DWI models for differentiating PDAC from SPNs and PNETs were higher than that of subjective diagnosis alone (P < 0.05). The non-gaussian DWI models could assist radiologists in accurately differentiating PDACs from PNETs and SPNs. • The DWI model yielded AUCs of 0.87 and 0.86 for distinguishing PDACs from PNETs in primary and validation groups. • This DWI model achieved AUCs of 0.916 and 0.891 for differentiating PDACs from SPNs in primary and validation groups. • The error rates were reduced when radiologists were assisted by the DWI models. [ABSTRACT FROM AUTHOR]

This study challenges the capabilities of artificial neural network (ANN) as well as response surface methodology (RSM) in estimating the viscosity (μ) and thermal conductivity (k) of β − SiC/EG and β − SiC/PG nanofluids. The implementation of these methods is performed by defining statistical criteria with a great obsession to forecast viscosity ratio as well as thermal conductivity ratio with the least error. The nanoparticle of β − SiC has a bigger effect on μ EG and μ PG so that they increase up to 78.71% and 56%, while k EG and k PG improve under the best conditions up to 14.64% and 4.85%, respectively. Statistical calculations show that for RSM, R-square is 0.987 for μ β − SiC / EG μ EG , 0.975 μ β − SiC / PG μ PG , 0.99 k β − SiC / EG k EG and 0.987 k β − SiC / PG k PG . This figure for ANN is 0.994, 0.992, 0.994 and 0.991. This implies that ANN ability is superior. Although β − SiC nanoparticles increase the viscosity by 78.7% (for EG) and 56% (for PG) which is not desirable, fortunately, fluid mechanics-based calculations reveal that in turbulent regime, the pumping power increases by only 17.2% and 13.5% under worst conditions. [Display omitted] • Numerical study on β-SiC nanoparticles efficacy on performance of EG and PG liquids. • ANN implementation had superior fitting criteria to RSM. • Loading β − SiC improved thermal conductivity by 14.64 and 4.85% for EG and PG. • Incorporation of β − SiC amplified the viscosity by 78.7 and 56% for EG and PG. • Pumping power increased by only 17.2% and 13.5% in turbulent regime. [ABSTRACT FROM AUTHOR]

Spinning Mode Synthesizer is an effective engine noise test rig for aero-engine noise propagation and radiation research. Spinning mode generation is realized through amplitude modulation and phase shift between individual loudspeakers. The target spinning mode is not the primary mode. It is even submerged in the undesired modes due to the system error of artificial source generators, especially the magnitude and phase mismatch of loudspeakers. In this paper, a global calibration factor is used to minimize the effect of loudspeaker nonuniformity in mode generation. The mode generation process of the calibrated system is mainly divided into two steps. The first step is to identify the calibration factors of individual loudspeakers with an optimized microphone array, which is used primarily for mode analysis. No particular error sensor or additional devices is used in the measurement. The theoretical complex source strengths are multiplied by the calibration factor to calibrate artificial source generators. The second step is to carry out mode generation experiments using the calibrated system, and Radial Mode Analysis is used to analyze the mode components in the duct. A spinning mode synthesizer with three axially spaced rows of loudspeakers is introduced, and each row consists of 12 excitation units. The maximum controllable circumferential mode order is m = 9, and the maximum controllable radial mode order is n = 2. It has been proven that the calibrated system can generate the target mode more precisely, and the mode coefficient signal-to-noise ratio ( SNR A) of any propagable mode is greater than 10 dB in the operating frequency range. [ABSTRACT FROM AUTHOR]

Compared with conventional word embeddings, sentiment embeddings can distinguish words with similar contexts but opposite sentiment. They can be used to incorporate sentiment information from labeled corpora or lexicons by either end-to-end training or sentiment refinement. However, these methods present two major limitations. First, traditional approaches provide a fixed representation to each word but ignore the alternation of word meaning in different contexts. As a result, the polarity of a certain emotional word may vary with context, but will be assigned with a same representation. Another problem is the handling of out-of-vocabulary (OOV) or informal-writing sentiment words that would be assigned generic vectors (e.g., ). In addition, if affective words are not included in affective corpora or lexicons, they would be treated as neutral. Using such low-quality embeddings for building a neural model will reduce performance. This study proposes a training model of contextual sentiment embeddings. A stacked two-layer GRU model was used as the language model, simultaneously trained to incorporate semantic and sentiment information from labeled corpora and lexicons. To deal with OOV or informal-writing sentiment words, the WordPiece tokenizer was used to divide the text into subwords. The resulting model can be transferred to downstream applications by either feature extractor or fine-tuning. The results show that the proposed model can handle unseen or informal writing sentiment words and thus outperforms previously proposed methods. [ABSTRACT FROM AUTHOR]

Surface barriers are influencing the mass transfer in nanopores, but their origin is unclear and can be quite different in different materials. For MFI and CHA membranes studied here, we show that the surface barrier may be a surface diffusion process with higher activation energy than the surface diffusion process in the pores, but other possible mechanisms such as pore blocking and pore narrowing has not been ruled out. The higher activation energy is probably a result of less interaction between adsorbed molecules at the pore mouth than inside the pores, i.e. the barrier is simply a geometrical effect in these materials. For pure components at low concentration in MFI zeolite, we found that barrier is proportional to the product of the molecular weight and heat of desorption. For MFI and CHA zeolite, we observed that the barrier is a function of concentration and approach zero at high concentration and that the barriers of the components become more similar due to interaction between the components in mixtures, which explains the high and selective mass transfer displayed by these nanoporous materials at high concentration. [Display omitted] • The surface barrier is a surface diffusion process with high activation energy. • The MFI surface permeability inversely proportional to M w and ΔH ads. • More similar surface permeabilities in mixtures, which results in high selectivity. [ABSTRACT FROM AUTHOR]

In this manuscript we investigate the one-dimensional anisotropic XY model with ferromagnetic and antiferromagnetic interactions, which gives more interesting phase diagram and dynamic critical behaviors. By using quantum renormalization-group method, we find that there are three phases in the system: antiferromagnetic Ising phase ordered in " x direction", spin-fluid phase and ferromagnetic Ising phase ordered in " y direction". In order to study the dynamical critical behaviors of the system, two quantum quenching methods are used. In both cases, the concurrence, a measure of entanglement, oscillates periodically over time. It if found that in the both cases the periods are the same and can be used as a order parameter for quantum phase transitions. It is also found that there is a scaling behavior for the evolution period and a reciprocal relation for the evolution period exponent, θ and correlation length exponent, ν. [ABSTRACT FROM AUTHOR]

• Molecular dynamics method was implemented. • Effect of the ultrasonic flow on the vibrational behavior of carbon nanotubes was investigated. • As the temperature and pressure of the simulated samples increase, the oscillation amplitude decreases. • With increasing temperature and pressure, these structures' frequency value rises. The carbon nanotubes are among the most robust materials known to main (both in terms of tensile strength and vibrational properties). This strength is derived from the covalent bonds between carbon particles. In this research, carbon nanotubes in different sizes and chiralities and argon flow at supersonic velocity are simulated with molecular dynamics simulations, and their mechanical behavior is investigated. In this study, the stability of atomic structures, the effect of temperature and pressure on carbon nanotubes' vibrational behavior, and the effect of the velocity of argon atoms (ultrasonic flow) on the vibrational behavior of carbon nanotubes were investigated. Numerically, as the temperature and pressure of the simulated samples increase, the numerical value of the oscillation amplitude decreases to 2.12 Å and 2.30 Å, respectively. Also, with increasing temperature and pressure, these structures' frequency value rises to the numerical value of 13.02 ps−1 and 12.59 ps−1, respectively. [ABSTRACT FROM AUTHOR]

Monolithic binder-free CO 2 adsorbents with high adsorption capacity, selectivity, adsorption-desorption kinetics, and regenerability are highly desired to both reduce the environmental impact of anthropogenic CO 2 emissions and purify valuable gases from CO 2. Herein, we report a strategy to prepare monolithic carbonaceous CO 2 adsorbents from low-cost and underutilized bioresources, which enabled the formation of a delicate anisotropic, hierarchical porous structure. With optimized material composition and processing conditions, the biobased carbon adsorbent demonstrated a CO 2 adsorption capacity of 4.49 mmol g-1 at 298 K and 100 kPa, relatively weak adsorbent-adsorbate affinity, good CO 2 /N 2 selectivity, and advantageous hydrophobicity against water vapor. Moreover, the unique anisotropic porous structure provided high stiffness and good flexibility to the adsorbent in the axial and radial directions, respectively. We confirmed that this type of carbon adsorbent could be packed in a column for dynamic CO 2 capture independent of any binders, indicating its promising future for further development toward widespread utilization. [Display omitted] • Biocarbon aerogels with anisotropic, hierarchical porous structure were prepared. • Carbon aerogels reached CO 2 adsorption capacity of 4.49 mmol g−1 (298 K, 100 kPa). • Carbon aerogels showed good CO 2 /N 2 selectivity and low water vapor adsorption. • Carbon aerogels exhibited strong and unique anisotropic mechanical properties. • Carbon aerogels were packed in a column without binders for large-scale CO 2 capture. [ABSTRACT FROM AUTHOR]

Magnetic fabric analysis is a common technique to assess the strain regime during mountain building processes. Here, we use this approach to evaluate the tectonic evolution of the Tibetan Plateau and the Eastern Himalayan Syntaxis by analyzing the limestones of the Jurassic Buqu Formation in the Zaduo area, Eastern Qiangtang Terrane (China). These limestones were chemically remagnetized during the Cenozoic. For a proper assessment, it is relevant to understand how the mineralogy of the remagnetized limestones affects their magnetic fabric and how the magnetic fabric can improve our understanding of the tectonic strain and regional deformation. The role of the authigenic magnetite in the development of the magnetic fabric should thus be explored. Comparison of the bulk susceptibility (K m) with various natural and laboratory rock magnetic properties (K m versus natural remanent magnetization, K m versus saturation isothermal remanent magnetization, and K m versus saturation magnetization) indicates that susceptibility and remanences are both carried by authigenic magnetite. Most of the magnetite grains show axial ratios <1.3:1 according to the Néel diagram, and fall within the single-domain range based on the mass magnetic susceptibility (χ) and DC field-normalized anhysteretic remanent magnetization (χ ARM) ratio, giving rise to the inverse magnetic fabric observed. Twelve sites (120 specimens) are divided into four groups based on the magnetic fabric and rock magnetic behaviors. Overall, there is a clear trend of decreasing K m , natural remanent magnetization, saturation isothermal remanent magnetization, ferromagnetic percentage and shape parameter from Group I to IV. The K 1 axis of all four groups documents a NNE-SSW oriented compression during remagnetization, contrasting with the Eocene NE-SW compression in the Gongjue area farther east. This different compressional regime likely resulted in different rotations and structural trends surrounding the Eastern Himalayan Syntaxis. • Authigenic magnetite explains magnetic behavior of Zaduo remagnetized limestones. • Single domain magnetite particles cause the inverse magnetic fabrics. • These fabrics document NNE-SSW oriented compression during Eocene remagnetization. [ABSTRACT FROM AUTHOR]

The Non-synchronous Measurements (NSM) was proposed to enhance the accuracy of reconstruction and reduce the measurement cost. However, the investigated object of conventional NSM are only sparsely distributed sound sources, and little emphasis placed on the reconstructed accuracy of the spatially extended sound source. In this article, the traditional NSM is further investigated in the spatially extended sound source, and the sound pressure information is reconstructed by Bayesian compressive sensing algorithm (BCS). Firstly, the spatially extended sound source is scanned by moving the rectangular microphone array, and the measurement effects of the array with large aperture and high density are approximately obtained by using NSM technique. Then, BCS is applied to reconstruct sound field by the NSM of sound pressure. The results of numerical simulations provide evidence for the feasibility of applying the proposed investigation to the spatially extended sound source. NSM has advantages in reconstruction accuracy compared with the single measurement. At the same time, the reconstructed sound pressure under NSM can replace the simultaneous measurement (SM) results of multi-array, which avoids the limitation of using reference microphone in increasing the number of channels and spatial layout. The experimental results of the driven steel plate provide additional evidence to support the effectiveness and feasibility of the investigation. • The application problem of the NSM in the spatially extended sound source like the driven steel plate is investigated. • The NSM increases the number of microphones and avoids the limitation of using reference microphone in increasing the number of channels and spatial layout. • The traditional NSM is further investigated in the spatially extended sound source, and the sound pressure is reconstructed by BCS. [ABSTRACT FROM AUTHOR]

Allam cycle is an advanced semi-closed supercritical carbon dioxide (sCO 2) power cycle that utilizes hydrocarbon fuels with nearly zero carbon emission. Different from other closed power cycles, in the Allam cycle, the oxy-fuel combustion products are directly mixed with the working fluid and the turbine blade cooling is necessary for the high cycle temperature above 1000 °C; moreover, the heat integration might be applied to the Allam cycle to improve the thermodynamic performance, making the Allam cycle complex and hard to conduct the process and parameter optimization. To deepen the understanding on the performance of the Allam cycle with turbine cooling and recompression modification, a novel splitting analytical method is developed that the Allam cycle is split into the closed cycle and open process, and the closed cycle is further split into the simple host cycle and two equivalent power cycles. Using the constructed splitting analytical models, the influences of the turbine cooling and the recompression modification on the net efficiency are clearly evaluated by the split cycles, and the highest efficiency of the Allam cycle is optimized to be 49.92 % (higher heating value) as the coolant temperature and recompression mass flow rate are 320 °C and 439.5 kg/s, respectively. • The Allam cycle is split into the closed cycle and open process. • The closed cycle is further split into several simple cycles. • Turbine cooling and recompression are analyzed and optimized. • The highest net efficiency soars to 49.92 % based on higher heating value. [ABSTRACT FROM AUTHOR]

Ammonia (NH 3) blending combustion strategy has been regarded as a high-efficient form of NH 3 utilization. To understand the high-pressure gas-phase auto-ignition characteristics of NH 3 blending with diesel, the ignition delay times of NH 3 /diesel mixtures with high NH 3 energy fractions of 70%, 80% and 90% were measured in an ultrahigh-pressure rapid compression machine, at high pressures of 50–120 bar, temperatures of 755–996 K, and equivalence ratios of 0.5–1.5. As a consecutive study of Part 1 (Combust. Flame, 251 (2023), 112391), this study mainly focuses on the auto-ignition characteristics and oxidation mechanism of NH 3 /diesel mixtures at pressures higher than 50 bar. The ignition-promoting effect of increasing pressure from 50 to 120 bar was experimentally confirmed. Moreover, the increase of the diesel energy fraction, equivalence ratio, and oxygen concentration was found to decrease the ignition delay time of the NH 3 /diesel mixtures. The chemical reaction mechanism proposed in Part 1 was utilized to simulate the auto-ignition of the NH 3 /diesel mixtures. Simulation results show that the mechanism was able to quantitatively capture the ignition delay times of the NH 3 /diesel mixtures at the wide pressures. The cross-reactions between NH 3 and diesel, especially reaction RH + NH 2 = R + NH 3 , was found to play a key role in the correct prediction of auto-ignition at high pressure. In addition, it is revealed the effect of pressure is closely related to OH production reactions 2OH (+M) = H 2 O 2 (+M) and NO + HO 2 = NO 2 + OH, the rate of which increase with rising pressure. The reaction H 2 NO + O 2 = HNO + HO 2 is an important pathway where oxygen concentration affects NH 3 /diesel mixture auto-ignition. [ABSTRACT FROM AUTHOR]

Ni-Co Layered Double Hydroxide (LDH) shows great application potential in the field of anti-corrosion. However, the poor carrying capacity limits the performance of anticorrosion performance. In this study, Ni-Co hydrotalcite was grown on the surface of DE, and Ni-Co/DE@SP microcapsule with corrosion inhibitor loading up to 14.7% was successfully prepared. The adsorption capacity of Ni-Co/DE@SP for Cl− in 600 mmol/L NaCl solution was 6.72 mmol/g. It is worth noting that the impedance modulus of the prepared composite coating (EP/Ni-Co/DE@SP) is two orders of magnitude higher than that of the pure resin coating, and the wear resistance was improved by 33%. • The diatomite was used as the carrier, and the active filler with the synergistic anti-corrosion function was assembled. • The synergistic anti-corrosion of Ni-Co LDH adsorption of Cl− and passivation of corrosion inhibitor was realized. • The impedance modulus values of composite coating two orders of magnitude higher than that of the EP coating. • The friction loss and water absorption of the composite coating decreased by 33% and 51.36% respectively. [ABSTRACT FROM AUTHOR]

Pulmonary artery smooth muscle cells (PASMCs) phenotypic switching and pulmonary artery endothelial cells (PAECs) endothelial-mesenchymal transition (EndMT) are important in promoting pulmonary hypertension (PH)-pulmonary vascular remodeling (PVR). Resveratrol can efficiently inhibit the proliferation of PASMCs, but its application is limited due to its low bioavailability and solubility. In this study, we modified resveratrol to assess the role of A ring N(CH 3) 2 -based derivatives of resveratrol (Res4) in PVR-PASMCs phenotypic switching and PVR-PAECs EndMT. Chemical methods were used for the preparation of Res4; NMRS and HPLC were used to authenticate Res4. Mice developed PVR after 4 weeks of hypoxia (10% O 2). Res4 (50 mg/kg/d) attenuated right ventricular systolic pressure, right ventricular hypertrophy, and PVR. PASMCs developed phenotypic switching and PAECs developed EndMT after 2 days of hypoxia (3% O 2). Res4 (10 μM) could inhibit PASMCs and PAECs viability. Res4 could decrease proliferating cell nuclear antigen (PCNA) and osteopontin (OPN) expression, and increase α-smooth muscle actin (α-SMA) and vimentin expression in PASMCs. It could also decrease PCNA, α-SMA, vimentin expression and increase platelet endothelial cell adhesion molecule (CD31) expression in PAECs. Notably, Res4 inhibited the phosphorylation levels of mitogen-activated protein kinase kinase (MEK), extracellular signal-regulated protein kinase (ERK), Jun-N-terminal kinase (JNK), and p38 kinase in hypoxia-treated PASMCs and PAECs, indicating MAPK pathway may be involved in Res4-induced inhibition of PASMCs phenotypic switching and PAECs EndMT. Our data demonstrated that Res4 exerts antiproliferative effects by regulating PASMCs phenotypic switching and PAECs EndMT. Res4 may be potentially used as a drug against PH-PVR. [ABSTRACT FROM AUTHOR]

Identifying acoustic sources with high spatial resolution and precision is significant for machinery noise control. Off-grid compressive beamforming is an effective method for creating acoustic maps with a high spatial resolution. In this study, a two-dimensional off-grid compressive beamforming method via weighted block ℓ 1 norm regularization (WBS-OCSBF) is proposed. The weighted ℓ 1 norm offers a more uniform sparsity penalty compared to the ℓ 1 norm. This method can enhance the performance of off-grid compressive beamforming. Additionally, it is easily implemented on mature linear programming solvers and converges with only a few iterations. Numerical simulations are conducted to analyze the effects of several major parameters on the performance of the proposed method. The simulation results demonstrate the superiority of the proposed method over some traditional methods. The proposed method is then validated using a loudspeaker noises localization experiment. A gearbox transmission system and a transformer are used as two specific objects to explore the industrial application value. The proposed method can effectively localize the gear meshing noise and transformer discharge faults with a high spatial resolution. • Compressive beamforming via weighted Block L1 Norm is proposed in this paper. It enhances the spatial sparsity of the reconstruction results. • Simulation and speaker positioning experiments verify the effectiveness of the method. • Two industrial application experiments proved the potential industrial application value of the method proposed in this paper. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biohydrogen production through dark fermentation (DF) has been extensively reviewed. • Current and future status of DF-based biorefinery concepts have been discussed. • Two-stage anaerobic digestion could be the sustainable option for DF system upscaling. • Energy recovery, techno-economic and life cycle analyses are pointed out. • Present scenario of the DF-based biorefinery concept is evaluated using SWOT analysis. Green and clean hydrogen production has become a significant focus in recent years to achieve sustainable renewable energy fuel needs. Biohydrogen production through the dark fermentation (DF) process from organic wastes is advantageous with its environmentally friendly, energy-efficient, and cost-effective characteristics. This article elucidates the viability of transforming the DF process into a biorefinery system. Operational pH, temperature, feeding rate, inoculum-to-substrate ratio, and hydrogen partial pressure and its liquid-to-gas mass transfer rate are the factors that govern the performance of the DF process. Sufficient research has been made that can lead to upscaling the DF process into an industrial-scale technology. However, the DF process cannot be upscaled at the current technology readiness level as a stand-alone technology. Hence, it requires a downstream process (preferably anaerobic digestion) to improve energy recovery efficiency and economic viability. The article also discusses the possible hydrogen purification and storage techniques for achieving fuel quality and easy accessibility. The article further tries to unfold the opportunities, challenges, and current scenario/future research directions to enhance hydrogen yield and microbial metabolism, depicting the commercialization status for biorefinery development. Finally, the current progress gaps and policy-level loopholes from the Indian perspective are highlighted by analyzing the strengths, weaknesses, opportunities, and threats. [ABSTRACT FROM AUTHOR]

[Display omitted] • A urea assisted hydrogen evolution device with high energy saving efficiency was proposed. • NiMoO 4 NC/NT electrocatalyst exhibited excellent activity for both UOR and HER. • The flow field effect assisted electrocatalysis can achieve the best catalytic activity. • The structures of NiMoO 4 nanocrystalline were synthesized in situ for the first time. • The results of DFT calculation prove that Mo is the priority adsorption site for urea molecule. Coupling hydrogen evolution reaction (HER) with urea oxidation reaction (UOR) can significantly reduce the cell voltage, but also alleviate the environmental pollution caused by urea. We prepared NiMoO 4 nanocrystals (NC) in situ and cooperated with the hydrodynamics effect of nickel-micro tubes (NT), so that nanocrystals growing inside and outside the tube wall can fully react with electrolyte under the effect of flow field during the process of liquid flow, and achieve the best catalytic activity. Significantly, NiMoO 4 NC 400 /NT as electrode in coupled system achieving an ultralow cell voltage. And DFT calculations suggested a lattice oxygen involved urea oxidation reaction pathway with Ni-Mo site as the active site. Our approach can give a straightforward synthesis method for in-situ nanocrystal preparation, as well as break the shackles of standard water electrolysis and provide a new way to produce energy-saving hydrogen. [ABSTRACT FROM AUTHOR]

With the extensive exploration of advanced combustion modes and the increasing demand for engines with extremely high efficiency and low emissions, biodiesel has garnered significant attention and research as a renewable fuel source that boasts a wide range of raw materials. The ignition delay times (IDT) of methyl stearate, one of the main components in biodiesel, were measured in a new heated rapid compression machine (RCM). The data were obtained for the equivalence ratio of 0.3–0.8 and the compressed temperatures ranging from 820 K to 1000 K under three different pressures of 8, 10, and 12 bar. The influence of compressed temperature, compressed pressure, equivalence ratio, and oxygen mole fraction on ignition delay times was systematically discussed under experimental conditions, revealing the autoignition characteristics of methyl stearate in intermediate temperatures. Besides, the CRECK model and a skeletal model were verified against the experimental results, revealing that the model obtained by analogy significantly overestimates the low-temperature reactivity of methyl stearate. Furthermore, appropriate adjustments were made to the pre-exponential factors for the low-temperature elementary reactions in the CRECK model based on sensitivity analysis. The results indicate that the present model with optimization can well capture the dependence of the IDTs on the operating parameters under the investigated conditions, and the simulation results are in satisfactory agreement with the experimental data. Finally, the optimized model was verified against the experimental data from both the shock tube and jet-stirred reactor. To the authors' knowledge, this study represents the first gas-phase RCM experiment conducted on pure methyl stearate, which is a waxy solid at room temperature. [ABSTRACT FROM AUTHOR]

The Tianjin Biosecurity Guidelines for Codes of Conduct for Scientists are a set of ten principles designed to promote responsible science and strengthen biosecurity governance. They should be broadly adopted, including being endorsed by the Biological Weapons Convention at its 9th Review Conference in November 2022. [ABSTRACT FROM AUTHOR]

• Propeller jet-induced migration and distribution of PFAAs were investigated. • PFAAs in overlying water exhibited transient characteristics and hysteresis with time. • Variations in jet strength influenced the adsorption rates of PFAAs onto SPM. • V x and R yy promoted PFAA release from sediments. • Vorticity , DOC, and pH influenced PFAA distribution between SPM and overlying water. Perfluoroalkyl acids (PFAAs) are continuously accumulated in surface sediments due to extensive and long-term application. However, the mechanisms through which disturbances induced by ship propeller jets at the riverbed cause secondary release of PFAAs from sediments remain unclear. In this study, the effects of different propeller rotational speeds on PFAA migration, release, and distribution in multiphase media were investigated by performing indoor flume experiments combined with particle tracking velocimetry. Moreover, key factors influencing PFAA migration and distribution were identified, and partial least squares regression (PLS) method was applied to develop quantitative prediction models of relationships among hydrodynamics, physicochemical parameters, and PFAA distribution coefficients. The total PFAA concentrations (ΣPFAAs) in overlying water under propeller jet action exhibited transient characteristics and hysteresis with time after the disturbance. In contrast, the ΣPFAAs in suspended particulate matter (SPM) exhibited an upward trend throughout the process with consistent characteristics. The spatial distribution trends of PFAAs in overlying water and SPM at different propeller rotational speeds featured vertical variability and axial consistency. Furthermore, PFAA release from sediments was driven by axial flow velocity (V x) and Reynolds normal stress R yy , while PFAA release from porewater was inextricably linked to Reynolds stresses R xx , R xy , and R zz (p < 0.05). PLS regression models showed that variations in Vorticity , dissolved organic carbon, and pH influenced the decreases in PFAA distribution coefficients between SPM and overlying water (K D-SW) as propeller rotational speed increased, except for very long-chain PFAAs (C > 10). The increases in PFAA distribution coefficients between sediment and porewater (K D-SP) were mainly determined by physicochemical parameters of sediments, and the direct effect of hydrodynamics was relatively weak. Our study provides valuable information regarding the migration and distribution of PFAAs in multiphase media under propeller jet disturbance (both during and after disturbance). [Display omitted] [ABSTRACT FROM AUTHOR]

Isothermal compressive tests of a new hot isostatic pressed (HIPed) powder metallurgy (P/M) superalloy are performed at diverse deformation amounts, strain rates, and elevated temperatures. The impacts of hot compression parameters on the morphological evolution and dissolution behavior of γ' phase are studied. Results show that the morphology of γ′ phase changes from the various initial shapes (irregular, split-off branch, dendrite, butterfly-like, and cauliflower) to spherical, due to the overlap of the γ'/γ interface energy and the coherent strain energy related to lattice misfit. Besides, the dislocation accumulation leads to the increased local stress and enhances the spheroidization behavior of γ' phase. Increasing temperature/true strain or decreasing strain rate, the dynamic dissolution behavior of γ' phase is obvious. It is because the dislocation/ vacancies-assisted element diffusion is rapid at high deformation temperatures/true strains, and the low strain rate can provide the enough time for element diffusion. The substantial dissolution of γ' phase at 1140 °C and 1170 °C is also related to the deformation temperature approaching and exceeding the γ' solvus temperature (1150 °C), respectively. Additionally, the decreased fraction of γ' phase is also related to the high γ'/γ interfacial energy. To quantitatively describe the dissolution behavior of γ′ phase, a dynamic dissolution kinetics model is proposed, and the correlation coefficient between the predicted and experimental values is 0.990. It indicates that the proposed model can precisely depict the dissolution behavior of γ′ phase. The findings in this work can provide the theoretical guidance to optimize deformation parameters, as well as control the morphology and fraction of γ′ phases. • Dissolution and spheroidization mechanisms of γ′ phase in a novel HIPed P/M superalloy during hot deformation are studied. • The morphology of γ′ phase changes from the various initial shapes (irregular, split-off branch, et al.) to spherical. • The spheroidization of γ' phase mainly results from lattice misfit and the interaction between dislocation and γ' phase. • The dynamic dissolution behavior of γ' phase is obvious with increasing temperature/strain or decreasing strain rate. • The proposed dynamic dissolution kinetics model can precisely depict the dissolution behavior of γ′ phase. [ABSTRACT FROM AUTHOR]

Ammonia (NH 3) is considered as a good carbon-free hydrogen-carrier fuel and has gained extensive attention as a promising alternative fuel for internal combustion engine in recent years. To explore the application potential of the NH 3 burned with diesel fuel in internal combustion engine, the auto-ignition delay times of NH 3 /diesel fuel blends were measured in a rapid compression machine at a wide NH 3 energy fraction of 20%, 40%, 60%, 70%, 80%, and 90%, temperature range of 675–995 K, pressures of 20–50 bar, and equivalence ratios of 0.5–1.5. According to the variation of ignition delay times with temperature, three different combustion regimes for NH 3 /diesel mixtures can be determined. It is found that the typical NTC behavior and two-stage ignition process were only observed at the regime where diesel chemistry dominates. Both the first-stage and the total ignition delay times increase with rising NH 3 energy fraction, but decrease with the increase of equivalence ratio. Then, an updated NH 3 /diesel kinetic mechanism was proposed by adding new cross reactions between diesel and NH 3. Results show that the current mechanism exhibits an obvious improvement for ignition delay time prediction compared to the original mechanism, though it still fails to reproduce the ignition delay times of NTC range for the mixture containing 20% NH 3. Further sensitivity analysis and the OH radical rate of production analysis indicate that the overestimation of the reactivity for the NH 3 /diesel fuel blends at NTC range is closely related to reaction NO+HO 2 NO 2 +OH. The promoting effect of NO species on the conversion of inactive HO 2 radical into active OH radical at low temperature greatly accelerates the autoignition. In addition, the current mechanism does not include the cross reaction between the large NTC-related species (QOOH, OOQOOH, OQOOH, ROO) and the N-containing species (NO, NO 2 , NH 2), especially for the NO related reactions, which may have a great impact on the IDT simulation of the NH 3 /diesel mixtures. Consequently, this work presents new ignition delay time measurements and mechanism optimization for NH 3 /diesel mixtures. Continuous works should be emphasized on these unclear reactions to further understand the combustion behavior of NH 3 /diesel fuel blends. [ABSTRACT FROM AUTHOR]

Developing new techniques and materials for ethylene (C 2 H 4) and ethane (C 2 H 6) separation is an industrially significant but challenging task. Here we report two isoreticular pillar-layer metal-organic frameworks, Co(aip)(bpy) 0.5 and Co(aip)(pyz) 0.5 , for the separation of C 2 H 4 /C 2 H 6. The pore apertures of the pillar-layer metal-organic frameworks are rationally controlled by changing the length of the pillar ligands. Significantly, Co(aip)(pyz) 0.5 with a shorter pillar ligand shows reduced pore size and molecular sieving separation of C 2 H 4 from C 2 H 6. Co(aip)(pyz) 0.5 has a moderate C 2 H 4 capacity of 1.78 mmol/g but ultrahigh C 2 H 4 /C 2 H 6 selectivity exceeding 2000 at ambient conditions. The molecular simulation revealed that large torsion angle between the organic linker plane and Co–O bond leads to the high energy barrier for C 2 H 6 to enter into the pore, which results in the molecular sieving separation of C 2 H 4 /C 2 H 6. Dynamic breakthrough experiments confirmed the high selectivity of Co(aip)(pyz) 0.5 for C 2 H 4. And high-purity C 2 H 4 (>97%) with a C 2 H 4 productivity of 19.1 l/kg can be obtained through the desorption process. Meanwhile, the excellent reusability and moisture stability endow it great potential for applications in adsorptive separation. [Display omitted] • The pore apertures of the pillar-layer MOFs are rationally controlled. • Co(aip)(pyz) 0.5 showed the molecular sieving separation of C 2 H 4 /C 2 H 6. [ABSTRACT FROM AUTHOR]

[Display omitted] • A thin ceramic wafer was fabricated via an efficient phase inversion/sintering. • The thickness of the ceramic wafer was 250 μm with a mean pore size of 200 nm. • The high Al 2 O 3 loading helps their uniform distribution on membrane surface. • This wafer exhibited an ultrahigh and stable flux and oil removal efficiency. • The fouling analysis shows the dominant fouling mechanism was cake filtration. Efficient preparation of ceramic membranes helps to reduce costs and makes them more competitive in the field of wastewater treatment. In this work, an ultrathin Al 2 O 3 ceramic wafer membrane with a thickness of 250 µm and the mean pore size of approximately 200 nm was prepared from the Al 2 O 3 /polysulfone slurries via a casting-phase inversion/sintering approach. This ultrathin and hydrophilic ceramic wafer has a fully sponge-like and slightly asymmetric structure and desirable porosity, endowing it with an exceptionally high pure water permeability of ∼ 45,000 L m-2h−1 bar−1, an ultrahigh and stable emulsion flux of 2500 ∼ 3500 L m-2h−1 bar−1, as well as a high oil rejection of 99 % against real oilfield produced water (OPW). In addition, the increased Al 2 O 3 content enhanced the thermodynamic instability of the ceramic slurry, leading to the enhanced interfacial instability, which contributes to the uniform distribution of Al 2 O 3 particles on the precursor membrane surface to some extent during the phase inversion process, thus to reduce the surface defects of ceramic membranes after sintering. The membrane fouling analysis revealed that the dominant fouling mechanism was cake filtration, indicating the formation of a relatively dense and smooth skin layer of the ceramic wafer, which endow it with a high flux recovery ratio of 97.8 % by a simple chemical cleaning after OPW filtration. [ABSTRACT FROM AUTHOR]

Autoignition characteristics of methyl palmitate (C 17 H 34 O 2), a waxy solid at room temperature, were investigated in a newly developed heated rapid compression machine. Ignition delay times (IDT) of methyl palmitate were firstly measured at the low-to-intermediate temperatures of 780–980 K and equivalence ratios of 0.3–1.0 under three pressures of 10, 15, and 20 bar. A negative effect of the increase in compressed pressure, equivalence ratio, and oxygen mole fraction on IDTs at different compressed temperatures was qualitatively and quantitatively revealed. Besides, the dependence of IDTs on compressed pressure and equivalence ratio decreases with increasing temperature. A recently optimized mechanism was used to predict the experimental results. The simulations show an obvious negative temperature coefficient (NTC) behavior at the compressed temperatures of 780–830 K which was not observed in the experiment. Meanwhile, the mechanism pronouncedly underestimated the reactivity of methyl palmitate at higher temperatures in this study. Sensitivity analyses at different temperatures and pressures for equivalence ratios of 0.5 were conducted to determine the crucial reactions that caused the difference between the simulation and experiments. On this basis, further optimization was carried out and the simulation results of the latest mechanism show a good agreement with the experimental data. It is verified against shock tube experimental data that the optimization adjustment in this paper has a small positive impact on the prediction ability of the originally documented mechanism under temperatures above 1000 K. In the end, validation for the optimized mechanism against experimental data in a jet-stirred reactor (JSR) was performed. Overall, the experimental results fill in gaps in IDT data on methyl palmitate at low-to-intermediate temperatures and provide a reference IDT database for the development and validation of methyl palmitate mechanisms. [ABSTRACT FROM AUTHOR]

• Under the constraints of mean-square error, we formulate a new beampattern matching model of microphone based on the superdirective beamforming. • On the premise of sacrificing the frequency invariance of the sidelobe region, we improve the WNG of array while maximizing the DF. • We present FIB synthesis algorithm with low computational complexity by utilizing ADPM framework, which locally updates the penalty parameters. • Numerical simulations are proposed to assess the effectiveness and the convergence of the proposed algorithm. Frequency-invariant (FI) beamformers play an important role in suppressing speech waveform distortions. Due to the perfect FI beampattern (FIB), differential microphone arrays (DMAs) have been widely used in practical applications like voice communication and human-machine interface systems. Superdirective beamforming generated by DMAs have many useful properties but suffer white noise amplification. To address this drawback, we formulate a least squares broadband FI problem, under the white noise output power constraints, to improve robustness of superdirective beamformers. The problem is challenging to solve since FI beamformers are designed on broadband and initialization parameters corresponding to each frequency are different. We devise broadband beampattern synthesis algorithm based on alternating direction penalty method (ADPM), which utilizes the relationship between residuals and penalty terms to reduce the iteration number under the improved framework of alternating direction method of multipliers (ADMM). The proposed ADPM method can decompose the optimization problem into multi-block convex optimization problems and solve them separately. The fast convergence property of our solution is demonstrated via numerical simulations. [ABSTRACT FROM AUTHOR]

• The artificial microbial consortium was adapted in the pretreated materials. • dCBP by the adapted microbial consortium was realized to produce d -glucaric acid. • dCBP had the most integrated bioprocess without filtration and autoclave. • A closed-circuit circulation from pretreatment, dCBP to separation was established. • The closed-circuit circulation was environment-friendly without waste water. d -glucaric acid production from lignocellulose is a valuable research field, but meets the same challenge as other biorefinery processes that prevents it from commercialization, high production costs. The very path to tackle this is to increase the titer, rate and yield (TRY) of d -glucaric acid production and simplify the process, on which this study focused. Herein we used a novel, clean and environmentally friendly pretreatment, subcritical water pretreatment (SCWP), based on which we compared consolidated bioprocessing (CBP) by the microbial consortium composed of Trichoderma reesei C10 and Saccharomyces cerevisiae LGA-1C3S2 with separated hydrolysis and fermentation (SHF). CBP was found to be advantageous over SHF because of its comparable yield, much more simplified bioprocess and bigger space for cost reduction. Then CBP was upgraded to direct consolidated bioprocessing (dCBP) by adapting the microbial consortium in the raw liquors of SCWP containing inhibitors and toxic chemicals. As a result, more integrated biorefinery processes from corn stover (CS), wheat straw (WS), rice straw (RS) and switchgrass (SG) to d -glucaric acid under SCWP were developed and scaled up from shake flasks to 10 L fermenters, stirred and airlift. The TRYs of d -glucaric acid were improved significantly. The airlift fermenter was preferable for the dCBPs, producing the highest concentrations of d -glucaric acid, which were 10.03 g/L from subcritical water pretreated CS (SWCPCS), 9.53 g/L from SWCPWS, 8.87 g/L from SWCPRS and 10.66 g/L from SWCPSG respectively. Subsequently, the dCBPs were coupled with the downstream separation to establish a closed-circuit circulation and 30 rounds was run successfully. The highly integrated process from lignocellulose to d -glucaric acid with the smallest number of single unit operations was obtained and reported for the first time, providing an important design for biorefinery. This work is of great significance for biomanufacturing d -glucaric acid and other bio-based chemicals. [ABSTRACT FROM AUTHOR]

Green technologies for the manufacture of optical shutters retain a sustainable development. In this work, the electro-exploding wires and spray coating technologies are employed to deposit nanoparticulate (WO 3) 1-x (MoO 3) x composite films. MoO 3 NPs are introduced to enhance electrochromic (EC) transmittance variation of violet and UV light with wavelengths ranging from 330 to 450 nm. Measurements of EC performances of (WO 3) 1-x (MoO 3) x composite films in a potentiostat are carried out to discern beneficial from MoO 3 addition. It is observed that the diffusion coefficient and the charge density increase with an increment of MoO 3 concentration. The coloration efficiency at 430 nm raises apparently whereas that at 633 nm does not show a significant variation with increasing MoO 3 concentrations. In addition, the EC device with ∼12.5% of MoO 3 introduced reveals a much higher optical modulation at 430 nm. From the measurements of galvanostatic charge-discharge curves of EC films in the potentiostat, the areal capacitances of 12.9 and 14.0 mF/cm2 are estimated for pure and ∼12.5% MoO 3 introduced WO 3 EC films. The EC batteries are demonstrated and the enlarged energy storage capability with an addition of MoO 3 is observed. The simple introduction of MoO 3 into WO 3 nanoparticulate films compensates drawbacks of WO 3 films and enhances EC performances and energy storage capabilities. [Display omitted] [ABSTRACT FROM AUTHOR]

The understanding of the interactions between catalyst and support is very important in heterogeneous catalysis of water splitting; however, it is still lacking. Herein, a Fe-based material of rod-like Fe 2 OF 4 is fabricated as the oxygen evolution reaction (OER) electrocatalyst. Strikingly, Fe 2 OF 4 loaded on nickel foam support can exhibit high-efficient OER activity with low overpotential and Tafel slope. Furthermore, we reveal that partial ferric ions within Fe 2 OF 4 can leach out into electrolyte; and then the ferric ions are electrochemically adsorbed on the surface of nickel foam, triggering dynamic surface reconstruction to generate highly active FeNi-oxyhydroxides under alkaline OER condition. Further, based on our findings, a promising approach is successfully proposed to prepare a large-size, low-cost and high-performance OER electrode via surface reconstruction on NF with ferric ions, showing remarkable performance. This work provides new insights into catalyst-support interactions, and proposes a straightforward surface reconstruction strategy for the scaling-up of electrocatalysts. [Display omitted] • A Fe-based material of rod-like Fe 2 OF 4 is successfully fabricated as OER catalyst. • There are strong interactions between Fe 2 OF 4 and NF support. • Ferric ions will leach from the Fe-based catalyst during OER process. • The ferric ions can trigger the dynamic surface reconstruction of nickel foam (NF). • The dynamic surface reconstruction of NF generates highly active FeNi-oxyhydroxides. [ABSTRACT FROM AUTHOR]

• Compared the transcriptome profiles of between ucMSCs and bmMSCs of giant panda. • 478 genes upregulated, 601 genes downregulated in ucMSCs compared with bmMSCs. • PI3K-AKT pathway was more activated in ucMSCs compared with bmMSCs. Mesenchymal stem cells (MSCs) have pluripotent differentiation ability and play an important role in human clinical cell therapy. While, the research on MSCs in endangered wild animals is extremely rare. In our previous studies, the bone marrow mesenchymal stem cells (bmMSCs) and umbilical cord mesenchymal stem cells (ucMSCs) of giant panda (Ailuropoda melanoleuca) were successfully isolated. We aimed to characterize the differences in gene expression profiles between these two types of MSCs using RNA sequencing (RNA-Seq) and to determine which potential pathways are involved in functional regulation. In total, 1079 significantly differentially expressed genes (DEGs) were identified, of which 478 genes were upregulated and 601 genes were downregulated. The significantly enriched Gene Ontology (GO) terms mainly contained cell adhesion, biological adhesion, intracellular signal transduction, molecular function regulator, Ras protein signal transduction, small GTPase mediated signal transduction, and regulation of Rho protein signal transduction. The most enrichment pathways of DEGs enriched in Kyoto Encyclopedia of Genes Genomes (KEGG) were PI3K-AKT signaling pathway, Rap1 signaling pathway, MAPK signaling pathway, Hippo signaling pathway, Wnt signaling pathway, cGMP-PKG signaling pathway and Signaling pathways regulating pluripotency of stem cells. In addition, quantitative real time polymerase chain reaction (qRT-PCR) showed that the AKT3 , CDK2 , MAPK3 , mTOR , PI3K and PTK2 genes associated with PI3K-AKT pathway were highly expressed (P < 0.01), and Caspase-3 was low expressed (P < 0.05) in ucMSCs group when compared with bmMSCs. After treatment with the PI3K inhibitor LY294002, genes AKT3, CDK2, MAPK3, mTOR, and PTK2 were significantly decreased in ucMSCs (P < 0.01), and Caspase-3 was significantly up regulated (P < 0.001). In conclusion, we for the first time compared and analyzed the transcriptome profiles of giant panda ucMSCs and bmMSCs, and found the PI3K-AKT pathway was highly activated and might be a key signaling pathway in the ucMSCs regulation. This study will be beneficial for the research on MSCs proliferation regulation and differentiation of giant pandas in the future, and lay the foundation for MSCs application and clinical therapy for endangered wild animals. [ABSTRACT FROM AUTHOR]

• Compared the transcriptome profiles of between ucMSCs and bmMSCs of giant panda. • 478 genes upregulated, 601 genes downregulated in ucMSCs compared with bmMSCs. • PI3K-AKT pathway was more activated in ucMSCs compared with bmMSCs. Mesenchymal stem cells (MSCs) have pluripotent differentiation ability and play an important role in human clinical cell therapy. While, the research on MSCs in endangered wild animals is extremely rare. In our previous studies, the bone marrow mesenchymal stem cells (bmMSCs) and umbilical cord mesenchymal stem cells (ucMSCs) of giant panda (Ailuropoda melanoleuca) were successfully isolated. We aimed to characterize the differences in gene expression profiles between these two types of MSCs using RNA sequencing (RNA-Seq) and to determine which potential pathways are involved in functional regulation. In total, 1079 significantly differentially expressed genes (DEGs) were identified, of which 478 genes were upregulated and 601 genes were downregulated. The significantly enriched Gene Ontology (GO) terms mainly contained cell adhesion, biological adhesion, intracellular signal transduction, molecular function regulator, Ras protein signal transduction, small GTPase mediated signal transduction, and regulation of Rho protein signal transduction. The most enrichment pathways of DEGs enriched in Kyoto Encyclopedia of Genes Genomes (KEGG) were PI3K-AKT signaling pathway, Rap1 signaling pathway, MAPK signaling pathway, Hippo signaling pathway, Wnt signaling pathway, cGMP-PKG signaling pathway and Signaling pathways regulating pluripotency of stem cells. In addition, quantitative real time polymerase chain reaction (qRT-PCR) showed that the AKT3 , CDK2 , MAPK3 , mTOR , PI3K and PTK2 genes associated with PI3K-AKT pathway were highly expressed (P < 0.01), and Caspase-3 was low expressed (P < 0.05) in ucMSCs group when compared with bmMSCs. After treatment with the PI3K inhibitor LY294002, genes AKT3, CDK2, MAPK3, mTOR, and PTK2 were significantly decreased in ucMSCs (P < 0.01), and Caspase-3 was significantly up regulated (P < 0.001). In conclusion, we for the first time compared and analyzed the transcriptome profiles of giant panda ucMSCs and bmMSCs, and found the PI3K-AKT pathway was highly activated and might be a key signaling pathway in the ucMSCs regulation. This study will be beneficial for the research on MSCs proliferation regulation and differentiation of giant pandas in the future, and lay the foundation for MSCs application and clinical therapy for endangered wild animals. [ABSTRACT FROM AUTHOR]

Due to the serious threat of methanol to human health, the convenient, quick and specific detection of methanol is of great importance. Therefore, in this study, a biomass-derived chiral nematic composite film is fabricated by the co-evaporation of cellulose nanocrystals (CNC) and water-soluble polymer of β-cyclodextrin (PCD). The freestanding iridescent CNC-PCD film shows distinguishing structural colors of red and yellow green for methanol and ethanol respectively, realizing the identification of the two homologous alcohols by naked eyes. Besides, the quick, reversible and quantitative colorimetric sensing of the CNC-PCD film to methanol is verified. As its structural color and maximum reflection wavelength redshift to the greatest extent for methanol than other alcohols, the CNC-PCD film exhibits the specificity and selectivity for methanol detection in both single and mixed solvents. Such less-consumed and easy-to-handle CNC-PCD film may be useful as a colorimetric sensor to detect or discriminate methanol in some industrial products. A novel and green chiral nematic CNC-PCD composite film was fabricated from two types of important sustainable polysaccharides, CNC and β-CD. CNC-PCD can be used for the quick, reversible and specific colorimetric sensing of methanol. [Display omitted] [ABSTRACT FROM AUTHOR]

Burning oxygenated hydrocarbon biofuels in engines is a viable path for saving energy and reducing carbon emissions. N-butanol and biodiesel are two representative biofuels and have attracted widespread interest. In this study, the blends of n-butanol and biodiesel (a waste cooking oil) with different n-butanol ratios (40%, 60%, 80% by volume) were adopted to study their autoignition characteristics in a newly developed ultrahigh-pressure rapid compression machine. The ignition delay times of the blends were precisely measured under wide pressures of 10/20/40/60 bar, equivalence ratios of 0.3/0.5/1.0, and a temperature range of 700–970 K. Experimental results show that the ignition delay time decreases with the increase of pressure and equivalence ratio at the investigated conditions regardless the blending ratios. It is also found that the ignition delay time becomes slightly longer with the increasing n-butanol ratio in the blends at temperatures below 820 K. However, as the temperature further increases, the ignition delay times of different blends get closer and has a crossover tendency. The composition of the biodiesel was quantitively analyzed and a surrogate fuel was developed. An optimized mechanism was proposed based on a documented detailed mechanism with 461 species and 18,217 reactions. Simulation results show that the optimized mechanism better captures the dependence of the measured ignition delay times on temperature, pressure, and blending ratios over the entire temperature range compared to the original mechanism. In the end, species evolution and sensitivity analysis were performed sequentially with the optimized mechanism to give kinetics insight into the chemical interaction between biodiesel and n-butanol. The experimental data and modeling results reported here provide a basis for understanding the combustion reaction kinetics of biodiesel/n-butanol blending fuels. [ABSTRACT FROM AUTHOR]

[Display omitted] • A Z-scheme Ti-MOF/QDs/ZIS photocatalyst was fabricated. • The Ti-MOF/QDs/ZIS shows outstanding photocatalytic antibiotics degradation performance. • The Ti-MOF/QDs/ZIS exhibits excellent photocatalytic hydrogen evolution activity. • Ti-MOF/QDs/ZIS was very stable and easily recycled for reuse. • A possible mechanism for Ti-MOF/QDs/ZIS photocatalyst was proposed. Herein, a novel all-solid-state Z-scheme NH 2 -MIL-125(Ti)/Ti 3 C 2 MXene quantum dots/ZnIn 2 S 4 (Ti-MOF/QDs/ZIS) photocatalyst was prepared, then applied for photocatalytic antibiotic (tetracycline and sulfamethazine) degradation and hydrogen evolution under visible light. The Z-scheme Ti-MOF/QDs/ZIS photocatalyst afforded very efficient degradation of tetracycline (TC, 96% in 50 min) and sulfamethazine (SMZ, 98% in 40 min), as well as a high rate of hydrogen generation (2931.9 μmol g-1 h−1) under visible light irradiation. Trapping studies showed superoxide radicals (•O 2 −) to be the main active species for antibiotic degradation, with the intermediates formed during antibiotic photo-oxidation identified by liquid chromatography-mass spectrometry. Photocatalyst recycling studies showed the Z-scheme composite photocatalyst to be stable during both antibiotic photodegradation and hydrogen generation experiments. The Ti 3 C 2 MXene quantum dots facilitated electron transfer between the semiconducting components of Z-scheme composite photocatalyst. This work identifies a promising new Z-scheme photocatalyst system for water purification and solar hydrogen production. [ABSTRACT FROM AUTHOR]

• The non-synchronous measurements in the large-aspect-ratio cabin is investigated. • Non-synchronous measurements is applied to suppress reverberation interference. • The optimal spherical array measurement scheme and basis functions are determined. The resolution of conventional acoustic imaging methods in a large-aspect-ratio cabin is reduced seriously by array parameters limitation and reverberation. The non-synchronous measurements technique breaks through the limitation of array shape and the number of microphones. This method can approximate the result of synthetic large-aperture array acoustic imaging. The increase in the number of microphones and low-rank constraint assumption in non-synchronous measurements suppress the reverberation interference. The low-rank constraint filters out the eigenvalues of the reverberation sound other than the main noise sources, which is acted as an eigenvalue filter. It has been demonstrated that non-synchronous measurements with 3D beamforming can improve the resolution of acoustic imaging in cubic space, but the related research on the large-aspect-ratio cabin is still missing. The non-synchronous measurements method is applied to achieve high-resolution acoustic imaging in a large-aspect-ratio cabin in this paper. The array measurement scheme is investigated comprehensively, including the number of non-synchronous measurements, the array step distance and appropriate spatial basis functions. The experimental results show that the non-synchronous measurements can achieve high-resolution 3D acoustic imaging in the cabin of an urban rail vehicle. [ABSTRACT FROM AUTHOR]