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[Display omitted] • China's higher education system is fast-growing and facing major challenges in high-quality course development. • An innovative pass-through game (PTG) style teaching is designed by implementing humanistic theory. • A case study of chemical engineering principles course adopting PTG teaching is presented, showing great improvement in students' performance. The humanistic view has a far-reaching influence on education. This work presents an innovative pass-through game style teaching approach to improve the quality of classroom teaching in the rapid development of higher education in China, and creating a model for classroom teaching with a humanistic view. A case study in teaching "Chemical Engineering Principles 2" for undergraduate students in Quzhou University is presented, and great improvement in students' tests and national competition results, and their satisfaction have been demonstrated. Through the pass-through game style teaching, individual attention for students in big class can be realized. [ABSTRACT FROM AUTHOR]

Multi-label classification studies the task where each example belongs to multiple labels simultaneously. As a representative method, Ranking Support Vector Machine (Rank-SVM) aims to minimize the Ranking Loss and can also mitigate the negative influence of the class-imbalance issue. However, due to its stacking-style way for thresholding, it may suffer error accumulation and thus reduces the final classification performance. Binary Relevance (BR) is another typical method, which aims to minimize the Hamming Loss and only needs one-step learning. Nevertheless, it might have the class-imbalance issue and does not take into account label correlations. To address the above issues, we propose a novel multi-label classification model, which joints Ranking support vector machine and Binary Relevance with robust Low-rank learning (RBRL). RBRL inherits the ranking loss minimization advantages of Rank-SVM, and thus overcomes the disadvantages of BR suffering the class-imbalance issue and ignoring the label correlations. Meanwhile, it utilizes the hamming loss minimization and one-step learning advantages of BR, and thus tackles the disadvantages of Rank-SVM including another thresholding learning step. Besides, a low-rank constraint is utilized to further exploit high-order label correlations under the assumption of low dimensional label space. Furthermore, to achieve nonlinear multi-label classifiers, we derive the kernelization RBRL. Two accelerated proximal gradient methods (APG) are used to solve the optimization problems efficiently. Extensive comparative experiments with several state-of-the-art methods illustrate a highly competitive or superior performance of our method RBRL. • We present a novel multi-label classification model. • It can enjoy the advantages of Rank-SVM and BR, and tackle their disadvantages. • We derive the kernel model to obtain nonlinear multi-label classifiers. • The problems are solved efficiently by accelerated proximal gradient methods. • Extensive experiments have confirmed the effectiveness of our approach. [ABSTRACT FROM AUTHOR]

Although young people's mobility behaviors and their association with information and communications technologies (ICT) usage have been extensively researched, few studies have considered the relationship between changes in the use of ICT over time and young people's travel patterns. This paper explores how use of the Internet during adolescence/late childhood and the degree of change while transitioning from late childhood to adulthood is related to sustainable travel patterns in young adults. We are particularly interested in the mediating role that attitudes towards the environment have on the relationship between early age Internet use and sustainable travel in young adults. The use of rich, longitudinal datasets, the 2004 British Household Panel Survey (BHPS) and the Understanding Society Survey (Wave 4, 2012/14), allow an investigation of these attitudes and relationships for the same people from childhood to adulthood. We use structural equation modeling (SEM) to examine the complex interrelationships between young adults' Internet use over time, their travel modes and attitudes towards the environment, and other related behaviors. Our key finding is that consistently high levels of Internet use between adolescence and young adulthood is associated with the formation of environmental attitudes. While other factors not considered in this study might also have an effect, we find that these attitudes are indirectly but significantly associated with young adults' sustainable travel patterns and behaviors. [ABSTRACT FROM AUTHOR]

Abstract Multi-label learning is the problem where each instance is associated with multiple labels simultaneously. Binary Relevance (BR) is a representative algorithm for multi-label learning. However, it may suffer the class-imbalance issue especially when the label space is large. Besides, it ignores the label correlations, which is of importance to improve the performance. Moreover, labels might have positive and negative correlations in real applications, but existing methods seldom exploit the negative label correlations. In this paper, we propose a novel Cost-sensitive multi-label learning model with Positive and Negative Label pairwise correlations (CPNL), which extends BR to tackle the above issues. The kernel extension of the linear model is also provided to explore complex input–output relationships. Moreover, we adopt two accelerated gradient methods (AGM) to efficiently solve the linear and kernel models. Experimental results show that our approach CPNL achieves a competitive performance to some state-of-the-art approaches for multi-label learning. Highlights • We propose a novel cost-sensitive multi-label learning model with positive and negative label pairwise correlations. • We introduce a new regularizer to exploit the negative label pairwise correlations. • Kernel extension of the linear model is provided to explore nonlinear input–output relationships. • Two accelerated gradient methods (AGM) are adopted to efficiently solve the linear and kernel model. • Extensive experiments have verified the effectiveness of our proposed method. [ABSTRACT FROM AUTHOR]

The leaking safety of air conditioner using R290 has been a research hotspot in recent years, one method to lower the risk of explosion after leakage is utilizing ventilation. For fresh air conditioner, it's common to use thermal anemometry and differential pressure flowmeters to measure ventilation flow rate. However, there is non-negligible error especially under low air volume flow rate conditions. In this paper, a novel integral-type air conditioner with heat recovery using R290 is proposed. And the relevant influencing parameters are analyzed and experimentally studied. The results show that tracer gas method is an effective way to measure ventilation flow rate, and the novel integral-type air conditioner can meet the needs of the ventilation standards. The air volume flow rates of indoor unit fan and outdoor unit fan are dominant factors affecting ventilation flow rate. The outlet area of exhaust air duct is more sensitive than the inlet area of fresh air duct in exerting influence on ventilation flow rate, while the indoor temperature has a mild impact on ventilation flow rate. • A novel integral-type fresh air conditioner with heat recovery using R290 is proposed. • Tracer gas decay method shows high stability in the measurement of ventilation flow rate of fresh air conditioner. • The air volume flow rates of indoor unit fan and outdoor unit fan are dominant factors affecting ventilation flow rate. • The ventilation flow rate of the proposed integral-type air-conditioner is up to 30 m ³/h, basically meeting the needs of a room within 12 m2. [ABSTRACT FROM AUTHOR]

Multi-label learning is the problem where each instance is associated with multiple labels simultaneously. Binary Relevance (BR), which comes from the idea of one-vs-all for multi-class classification, is a representative algorithm for multi-label learning. It ignores label correlations and may suffer the class-imbalance problem. However, BR is mostly implemented by decomposing into many independent binary classifiers and learning each individually, making it difficult to extend. Moreover, when extending BR by learning together, the mostly used least squared loss function is more suitable for a regression task rather than a classification task. In this paper, we propose a unified framework implementing linear BR for multi-label learning, which is easy to extend and can also be applied in one-vs-all for multi-class classification. We mainly focus on five popular convex loss functions. Experimental results show that the unified framework achieves competitive performances than traditional implementations and some other well-established algorithms for both multi-label learning and multi-class classification. Furthermore, logistic, exponential and least squared hinge loss functions are more suitable for multi-label learning, while logistic and least squared hinge loss functions are more suitable for multi-class classification. [ABSTRACT FROM AUTHOR]

A Moving droplet impacting a moving particle has been investigated numerically and experimentally. However, the collision with heat transfer is still absent. Therefore, this paper presents a moving droplet impacting a moving particle with heat transfer using the lattice Boltzmann method coupled with a modified immersed boundary method. The influence of Prandtl number (0.1 ≤ Pr ≤ 10) and Grashof number (−100 ≤ Gr ≤ 100) are taken into account. The results show that the vertical velocity of the particle (Uz) grows up against the increment of Pr and Gr. Uz has three stages based on Pr and Gr ≥ 0. And for Gr = −100, Uz is classified into four stages. Especially, for the last stage (at that time, the droplet separates from the particle), Uz varies slightly. [ABSTRACT FROM AUTHOR]

An efficacious approach to improve the catalytic performance of titanium silicalite-1 (TS-1) catalysts in epoxidation of allyl chloride with hydrogen peroxide has been developed. A series of modified TS-1 catalysts were prepared by corroding the classic TS-1 catalyst with different concentrations of tetrapropyl ammonium hydroxide (TPAOH) under controlled conditions. The resultant catalyst samples were characterized by XRD, ICP, N 2 -adsorption, FT-IR, UV–vis, SEM and TEM. The catalytic activity of the modified TS-1 catalysts is significantly improved, which could be attributed to the increase of the mesopore volume and pore diameter and decrease of the diffusion limitation but without obvious changes of the framework structure, framework Ti content, the outer surface shape and crystal size of the modified TS-1. Furthermore, the kinetics of the epoxidation of allyl chloride over TS-1-0.05 catalyst was also systematically studied, the apparent orders of reaction with respect to H 2 O 2 and allyl chloride are 0.68 and 0.62, respectively, and the activation energy of the epoxidation reaction on the TS-1-0.05 catalyst is 57.4 kJ mol −1 . [ABSTRACT FROM AUTHOR]

As the representative genetic and economic trait of ornamental fish, skin color has a strong impact on speciation and adaptation. However, the genetic basis of skin color pigmentation, differentiation and change is still not understood. The Midas cichlid fish with three typical body color transition stages of "black-gray‑gold" is an ideal model system for investigating the formation and change of fish body color. In this study, to investigate the regulatory role of the pair box 3 (pax3) gene in the early body color fading process of Midas cichlids, the complete cDNA sequence (3513 bp) of pax3 was successfully isolated from Midas cichlids (Amphilophus Citrinellus), and found to encode polypeptides of 491 amino acids. Expression patterns of the pax3 gene in tissues of Midas cichlids during different periods, including embryonic development and body color fading stages were detected by quantitative real-time PCR. The qRT-PCR analysis showed that pax3 was expressed in all tissues of adult fish, with a higher expression level in muscle and skin. The highest expression level in muscle tissue was significantly higher than that in other tissues (P < 0.05). During embryonic development, the expression tendency of pax3 was first increased and then decreased. In the three typical stages of early skin color fading from black to gold, pax3 expression in skin, caudal fin and scales all showed a downward trend. The expression level in the black stage was significantly higher than that in other stages (P < 0.05). Positive signal of pax3 protein was detected in the three typical skin color conversion stages, and the highest positive signal intensity was detected in the black stage, which was consistent with qRT-PCR results. After pax3 RNA interference, pax3 and the downstream genes mitf and tyr all decreased, while dct mRNA expression increased in the skin of fish. Western blotting also showed a decrease in pax3 protein concentration. Those results suggest that pax3 plays an important role in skin color formation, distribution and change in Midas cichlids through the melanogenesis pathway. • The full length of the pax3 cDNA sequence of Midas cichlids was identified using the RACE technique. • Expression patterns of pax3 in tissues of Midas cichlids during different periods were analyzed. • The highest positive signal of pax3 protein was detected in the black stage. • The Wnt signaling pathway is highly likely to exist in the melanin synthesis pathway of Midas cichlids. [ABSTRACT FROM AUTHOR]

• The effects of particle-droplet size ratio, Weber number, and collision factor are investigated. • Three regimes are identified: full coating, partial coating, and disintegration. • The partial coating regime can be divided into two sub-regimes according to Weber number. • The disintegration regime also has two sub-regimes, depending on Weber number. • The coating outcomes are summarized and the regime maps (We - α and B - α) are presented. A numerical approach based on lattice Boltzmann method (LBM) coupled with immersed boundary method (IBM) is applied to investigate the three-dimensional (3D) coating process of a moving droplet against a moving particle. Particle-droplet size ratio (2/15 ≤ α ≤ 2/3), Weber number (6.845 ≤ We ≤ 171.114) as well as collision factor (0 ≤ B ≤ 1.0) on the coating processes are taken into account. According to present simulation, three regimes are identified: full coating, partial coating, and disintegration. Moreover, the partial coating regime can be divided into two sub-regimes according to Weber number. And the disintegration regime also has two sub-regimes, depending on Weber number. The coating outcomes are summarized and the regime maps (We - α and B - α) are presented. The findings learned from this work can provide guides for many industrial applications. [ABSTRACT FROM AUTHOR]

The present work experimentally investigates a water droplet impacting a V-shape wall. The effects of eccentricity ratio (0 ≤ b ≤ 14/9), bending angle of the V-shape wall (90o ≤ θ ≤ 180o), Weber number (205.80 ≤ We ≤ 447.92), and droplet diameter (1.3 mm ≤ D ≤ 4.5 mm) are taken into account. In this work, the wrinkles of the lamella not only are observed on the flat wall but also on the V-shaped wall. As We decreases, the wrinkles of the lamella will be seldom observed. As θ increases, the size of the wrinkles decreases, while the number of the wrinkles increases. The secondary spray is observed for the eccentric collision of the droplet against the V-shaped wall. Especially, the secondary spray can be classified into two sub-regimes based on eccentricity ratio: secondary spray-I and secondary spray-II. For the secondary spray-I, the secondary spray and the primary splash form an angle, and the angle decreases against the increment of b. The nondimensional spreading length and height also are studied theoretically. [ABSTRACT FROM AUTHOR]

[Display omitted] • Coal fly ash by NaOH roasting enhances the volatilization of mercury at lower temperatures. • More water-soluble arsenic and selenium compounds are generated by NaOH roasting. • More acid-soluble lead and cadmium compounds are obtained by NaOH roasting. • NaOH roasting can effectively improve the recovery of rare earth elements in coal fly ash. Coal fly ash (CFA) has been considered an important alternative resource for rare earth elements (REEs) and other critical metals such as Ge, Ga, U, etc. Concerns regarding the migration and transformation of harmful trace elements (HTEs: Hg, As, Se, Pb, Cd, Cr) from CFA to the environment are of great significance for the technical design of the recovery of REEs from CFA as well as its economic evaluation and environmental impact assessment. Here, the migration and transformation of these HTEs during the recovery of REEs from CFA activated by NaOH roasting were investigated. The recovery of REEs from CFA was above 90% under the conditions of the alkali-to-ash ratio of 1.2 and roasting temperature of 318 °C. In the NaOH roasting process, mercury compounds, i.e., Hg 2 Cl 2 , HgCl 2 , and HgSO 4 , were converted into HgO, which was then partially reduced to elemental Hg (Hg0) in the water generated during the roasting process and promoted the release of Hg from CFA. In addition, other HTEs, e.g., As, Se, Pb, Cd, and Cr, were also transformed into compounds during the NaOH roasting process that were easier to be leached out during the following water and acid leaching process compared to that without the roasting process. For example, As compounds (As 2 O 5 , As 2 O 3 , Ca 3 (AsO 4) 2 , and FeAsO 4) were converted into Na 3 AsO 4. Se compounds (Se, SeO 2 , and CaSeO 3) were converted into Na 2 SeO 3. PbSO 4 and PbCl 2 were converted into PbO. CdCl 2 and CdSO 4 were converted into CdO. CrO 3 , CrCl 3 , and Cr 2 (SO 4) 3 were converted into Na 2 CrO 4 and NaCrO 2. The experimental results of this work provided insights into understanding the migration and transformation of these HTEs and the associated leaching behavior during the recovery of REEs from CFA activated using a NaOH roasting approach. [ABSTRACT FROM AUTHOR]

Although the associations between the use of information and communications technologies (ICT) and individuals' daily travel and activity patterns have been extensively investigated for several decades, few studies have examined the amount of time spent using ICT, its implications on activity-travel behavior, and how such ICT-travel relationships may vary over time and according to residential location. This study takes a quasi-longitudinal perspective to explore how the amount of time individuals spend on the Internet for personal or non-work purposes correlates to their activity-travel for non-mandatory maintenance and leisure purposes, as well as how such associations evolve over a decade. More importantly, it examines how the role of people's residential locations in determining the associations between time spent on the Internet and travel has changed over time. Our approach utilizes two datasets from two major cross-sectional surveys in Scotland: the 2005/06 Scottish Household Survey (SHS) and the 2015 Integrated Multimedia City Data (iMCD) Survey, which were similarly structured and developed. To accommodate the multiple discreteness characterizing activity-travel choice and duration, the multiple discrete-continuous extreme value (MDCEV) model was employed to capture the Internet–travel relationships for the full sample and the urban, town, and rural sub-samples in both 2005/06 and 2015. Our findings suggest that use of the Internet for personal purposes increasingly tends to discourage rather than facilitate physical activity and travel for non-mandatory purposes over time, especially for those who spend high levels of time on the Internet (over ten hours per week). However, such Internet–travel relationships are generally weaker among people living in remote areas than those living in urban areas. While the relationships regarding maintenance activity purposes are significant for almost all levels of Internet users among the urbanites in both years, they were not significantly found at all among rural residents in either 2005/06 or 2015. [ABSTRACT FROM AUTHOR]

• The effects of Weber number and particle-droplet size ratio are investigated. • For the fixed stationary particle, three regimes are observed: deposition, agglomeration and disintegration. • The deposition regime of the moving particle has two sub-regimes: deposition-I and deposition-II. • For the moving particle, the process of the droplet reaching breakage requires a large initial velocity. • But for the moving particle, the critical initial velocity Vinic depends sensitively on α. Droplet-particle collision is commonly found in nature and industry. The collision of a moving droplet against a fixed stationary particle has been investigated comprehensively, and the collision of a moving droplet against a moving particle also has been studied. However, there is no open literature to conduct a detailed comparison between the two occasions. In this study, the collision of a droplet against a moving/fixed stationary particle are studied by the lattice Boltzmann method, and a comprehensive comparison is made. The effects of Weber number and particle-droplet size ratio are investigated. For the collision of a moving droplet against a fixed stationary particle, three regimes are observed: deposition, agglomeration and disintegration. For the collision of a moving droplet against a moving particle, only two regimes are observed: deposition and disintegration. Moreover, for the first time, it is observed that the deposition regime of a droplet colliding against a moving particle can be divided into two sub-regimes. The variation of force of the particle is analyzed. The numerical results show that the amplitude of the vertical force of the fixed stationary particle is larger than its moving counterpart, although the fluctuation of the former will disappear quickly. The present study reveals the differences between the two collision situations, which are helpful to understand the collision phenomena in industrial applications. [ABSTRACT FROM AUTHOR]

Abstract: The negative effect of deicing salt on surface water have been reported by a number of studies, but there is a lack of knowledge about the effects of deicing salt on the growth behavior and the change of biochemical composition of algal Chlorella vulgaris (C. vulgaris). Algal were cultured at different concentration of deicing salt, algal cell densities, chlorophyll (a), protein and polysaccharides contents were measured. The results of this work showed that deicing salt had statistically significant inhibitory effects (P<0.01) on the cell growth of algae, and the best-fit predictive equation of algal cell densities (Dalgal, algal cells m/l) versus concentration of deicing salt (Csalt, g/l) after 7- day culture in this experiment was presented as a quadratic equation with Csalt being the independent variable and D algal being the dependent variable (R2=0.944, P<0.01). The contents of chlorophyll (a) in C. vulgaris cell exposed to different concentrations of deicing salt suggested that the chlorophyll (a) content significantly decreased (P<0.05) with the concentration of deicing salt higher than 4 g/l. Deicing salts also caused the trend of proteins contents decrease in C. vulgaris cells, and significantly increased (P<0.05) the contents of polysaccharides in algae cell at 2 g/l deicing salt, however, the change of that was not significantly affected at deicing salt concentrations higher than 2 g/l. [Copyright &y& Elsevier]

Abstract: The epoxidation of propylene with H2O2 catalyzed by a supported TS-1 catalyst in a fixed-bed reactor has been studied. The effects of methanol concentration (40–70wt.%), hydrogen peroxide concentration (5–20wt.%), propylene pressure (0.2–0.6MPa) and temperature (35–50°C) on the reaction are investigated. The experimental results show that the reaction rate increases with the increase in methanol concentrations, hydrogen peroxide concentrations, propylene pressure and temperature; the activation energy of the reaction is 46.8kJmol−1 and the reaction orders with respect to hydrogen peroxide and propylene are 0.32 and 0.68, respectively. The reaction was modeled with Eley–Rideal (E–R) and Langmuir–Hinshelwood (L–H) models, and the results show that the kinetic model of Eley–Rideal with H2O2 being adsorbed can give the best fit among the models compared for the epoxidation of propylene with H2O2. [Copyright &y& Elsevier]

Abstract: Hierarchical structured TiO2 nano-tubes were prepared following a two-step method: the highly ordered uniform TiO2 nanotube arrays were first grown by the conventional electrochemical anodization of the Ti metal sheet followed by mechanical milling of the as-fabricated TiO2 nanotube arrays. The obtained nanotubes with a length around 400nm and opening diameter ∼100nm were formed mixed with the spherical TiO2 single crystals with a diameter around 10nm indicating hierarchical nanostructure. The as-synthesized TiO2 hierarchical nanotubes based resistive-type chemical sensor exhibits good sensitivity to formaldehyde at room temperatures with or without UV-irradiation. The response of the sensor increased almost linearly as a function of the concentration of formaldehyde from 10–50ppm under UV irradiation. The response of the sensor to different relative humidity and other possible interferents such as ammonia, methanol and alcohol was investigated. The larger response of the sensor to formaldehyde relative to these interferents is suggested to be due to the deeper diffusion of formaldehyde into the TiO2 nanotubes. [Copyright &y& Elsevier]

Abstract: In order to solve the question of attitude stabilization of autonomous airship during spot hovering, this paper proposes a fault-tolerant backstepping control law. The strict-feedback discrete-time dynamics model of airship is obtained via Euler approximation. The discrete control law is designed by using the backstepping method to make the system uniform stable. By applying two-level strong track filters, which can detect and isolate step bias or time-varying bias sensor fault in both single fault or simultaneous faults scenario, a fault-tolerant control law is constructed. The simulation results show that the method can achieve expected tracking performance and robustness. [Copyright &y& Elsevier]

Abstract: We aimed to further define the pathway mediating the inhibitory effects of κ-opioid receptor stimulation on Ca2+ transients and hypertrophic responses to β1-adrenoceptor stimulation. We determined the effects of Trans-(±)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)-cyclohexyl]-benzeneacetamid methanesulfonate salt (U50,488H), a selective κ-opioid receptor agonist, on the enhancement of spontaneous Ca2+ transients and the induction of hypertrophy by isoprenaline, a β-adrenoceptor agonist, in cultured neonatal ventricular myocytes. The results were compared with those found with KN93, a selective Ca2+/calmodulin-dependent kinase (CaMKII) inhibitor, propranolol, a β-adrenoceptor antagonist, and verapamil, a L-type Ca2+ channel antagonist. Hypertrophy of cardiomyocytes was characterized by increases in (i) total protein content; (ii) cell size; and (iii) [3H]leucine incorporation. 10 μmol/l isoprenaline increased all three parameters. We also determined the expression of nuclear CaMKIIδ in response to U50,488H in the presence or absence of isoprenaline. To determine whether the effects of U50,488H were receptor-mediated, its effects were also measured following blockade of the κ-opioid receptor with nor-binaltorphimine. κ-Opioid receptor stimulation suppressed the stimulatory effect of isoprenaline on Ca2+ transients and cardiac hypertrophy, as did KN93, propranalol and verapamil. U50,488H also suppressed the expression of nuclear CaMKIIδB in the presence, but not in the absence of isoprenaline. These results suggest that the inhibitory effect of κ-opioid receptor stimulation on β1-adrenoceptor stimulation may also involve CaMKIIδ. [Copyright &y& Elsevier]

Nonuniform irradiance on the Photovoltaic (PV) array would cause mismatch problem and decrease the generated power. To relieve the negative effects of partial shading, reconfiguring the interconnection of the PV array is a favorable solution. However, the current reconfiguration techniques are usually limited by different corresponding factors, e.g., not suit for various instantaneous shade cases, the shortage of experts' knowledge or large amounts of data, easy coverage to local optima, and the strict assumptions for application. Therefore, in this paper a unsupervised adaptive PV array reconfiguration technique is proposed with a Divide and Conquer Q-Learning (DCQL) based array reconfiguration scheme designed to decrease the influence of partial shades. To testify the performance of the proposed PV array reconfiguration scheme, mathematic theoretical evaluation and electric characteristic analyses are made and compared with those obtained by the conventional Total-Cross-Tied (TCT) arrangement, SuDoKu connection, Genetic Algorithm (GA) based scheme, as well as some lately proposed Grasshopper Optimization Algorithm (GOA), Harris Hawks Optimizer (HHO), and Lo Shu (LS) technique based reconfiguration methods. Besides, additional estimation indices, including mismatch loss, fill factor, percentage power loss and percentage power enhancement are calculated with substantial analyses and comparisons. Subsequently, the application of the proposed scheme in real-time conditions is evaluated, with energy saving and income analysis estimated in comparison with other eminent challenger reconfiguration schemes. At last, a comprehensive qualitative comparison assessment, with respect to dispersion ability under partial shading conditions (PSC), sensor requirement, wiring complexity and capital investment is carried out and proves the versatility of proposed methodology. • States, actions and rewards are designed in the Q-Learning based reconfiguration. • The combination of divide and conquer principle fastens the decision making process. • The proposed reconfiguration is estimated better performance through variety contrasts. [ABSTRACT FROM AUTHOR]

One of the most important performance metrics for piezoelectric micromachined ultrasonic transducers (PMUTs) is their transmitting sensitivity, which is significantly dependent on the design of the transduction diaphragm. In this work, a comprehensive comparison of transmission sensitivities for PMUTs with circular, square, and hexagonal transduction diaphragms are investigated through theoretical calculations, finite element analysis (FEA), as well as experimental verifications. Compared to the PMUTs with circular and square transduction diaphragms, PMUTs with hexagonal transduction diaphragm can achieve greater volume displacement and hence better transmitting sensitivity as a transmitter, due to their higher fill-factor and larger quality factor (Q). The measured average resonant volume displacement and Q of 15 fabricated PMUTs with hexagonal transduction diaphragm are 3.07 × 10−13 m3/V and 798, respectively. The transmitting sensitivity of the hexagonal PMUTs exceeds that of the circular PMUTs by over 15% and that of the square PMUTs by over 3.5%. This work highlights an effective and simple approach for PMUTs to achieve high transmitting sensitivity. [ABSTRACT FROM AUTHOR]

This paper introduces an innovative transceiver integrated with high-performance piezoelectric micromachined ultrasonic transducers (PMUTs) array, specifically designed for breast cancer imaging. The PMUTs array is meticulously partitioned into drive and detection sections, optimizing the size ratios of the top electrodes within a transduction cell. In this configuration, the outer drive electrode facilitates ultrasonic wave transmission, while the detection electrode concurrently receives signals, enhancing both sensitivity and reducing the overall size of the breast cancer ultrasound imaging system. The sensor dimensions of the scandium-doped aluminum nitride (Sc x Al 1 − x N, x=9.5%)-based PMUTs array are compact, measuring 3.2 mm × 3.2 mm. Thorough characterization of the packaged PMUTs array is conducted using an industry-standard calibration instrument. Notably, the reported PMUTs array achieves an impressive receiving sensitivity of −162 dB (re: 1 V/ μ Pa) with a 40 dB gain, a transmitting sensitivity of 156 dB (re: 1 μ Pa/V), and a maximum drive nonlinearity of 0.21% at the resonant frequency. Comparative analysis with state-of-the-art commercially available transducers underscores the excellence of the transceiver integrated PMUTs array for breast cancer imaging applications. The outstanding performance and the integration of the transceiver design contribute to a significantly reduced footprint, rendering the reported integrated transceiver PMUTs array highly valuable for portable breast cancer imaging devices with promising commercial prospects. • We present a pioneering transceiver-integrated PMUTs array designed for breast cancer imaging applications. • In the disclosed PMUTs array, the drive electrode transmits waves, and the detection electrode receives signals. • The disclosed PMUTs array is competitive with commercial transducers, excelling in sensitivity and directivity. [ABSTRACT FROM AUTHOR]

Filament-like ZnO and rod-like ZnO were synthesized by hydrothermal method, and used as a component in CuO/ZnO catalysts. These catalysts were tested in hydrogenation of CO 2 to CH 3 OH and compared with the CuO/ZnO catalyst prepared via conventional coprecipitation process. It was found that the activities of these catalysts depended strongly on the morphology of ZnO. CuO/ZnO catalyst prepared with filament-like ZnO exhibited the best activity, the space time yield of methanol reached 0.55 g -MeOH /(g -cat h) with a 78.2% selectivity of methanol at H 2 /CO 2 = 3, 240 °C, 3.0 MPa and 0.54 mol/(g -cat h). Characterizations found that CuO/ZnO catalyst with filament-like ZnO exhibited stronger interaction between ZnO and Cu, and more oxygen vacancies. The performances of these catalysts for CO 2 hydrogenation were compared and discussed with their structure. [ABSTRACT FROM AUTHOR]

A series of sulfated TiO 2 supported Mo (x Mo/1.5ST) catalysts were synthesized successfully and evaluated for the transesterification of Jatropha seed oil (JO) to biodiesel. Extensive characterization exhibits that the well dispersed Mo oxide species, with Mo6+ and Mo5+ oxidation states, were formed on the surface of the sulfated TiO 2. The results indicate the presence of many sulfates species leads to the reduction of Mo6+ species to Mo5+ species. Furthermore, the catalytic activity of the x Mo/1.5ST catalysts gradually increases with the increase of Mo-loading, although the sulfates content and the total acid intensity decrease. The transesterification process was fully investigated, and the 10Mo/1.5ST shows the highest yield of biodiesel of up to 97.42%. Additionally, the possible mechanism for the JO transesterification over Mo/1.5ST was described, and the fuel properties of the as-synthesized biodiesel conformed to the current international standards. [Display omitted] • Sulfated TiO 2 supported Mo catalysts are synthesized for the production of biodiesel from Jatropha seed oil. • The sulfates content and Lewis acid strength of catalysts decrease gradually with the increasing Mo-loading. • Highly dispersed Mo oxide species can promote the transesterification of Jatropha seed oil. • 10Mo/1.5ST catalyst exhibits the excellent stability and regeneration in the transesterification reaction. [ABSTRACT FROM AUTHOR]

• A series of Zn/TS-1 catalysts are synthesized and characterized systematically. • Green and efficient epoxidation of 1-hexene and MO over Zn/TS-1 catalyst. • Well-dispersed Zn species can promote the epoxidation of 1-hexene and MO. • The stability and regeneration of 2% Zn/TS-1 in 1-hexene and MO epoxidation are explored. To improve the catalytic epoxidation activity of conventional TS-1 zeolite under acid-free conditions, a series of TS-1-supported zinc (x Zn/TS-1) catalysts were prepared and evaluated in the epoxidation of 1-hexene and methyl oleate (MO) with H 2 O 2 oxidant. The microstructure of x Zn/TS-1 was investigated using various characterization techniques, and the results showed that the introduction of Zn species was not only well dispersed on the surface of TS-1 but also did not disrupt the crystal structure of TS-1 and tetrahedral framework titanium. Furthermore, the Ti-O-Zn structure can be formed between Zn and Ti species through O-atomic coordination, which improves the vulnerability of the Ti-O bond to attack the H 2 O 2 molecule, and ultimately facilitates the epoxidation reaction between 1-hexene and MO. In addition, the 2% Zn/TS-1 catalysts showed optimal conversions of 45.7 % and 75.41 % for 1-hexene and MO, respectively, and exhibited good catalytic stability and regeneration during the epoxidation process. [Display omitted] [ABSTRACT FROM AUTHOR]