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Powder‐based piezo‐catalysis, as an effective approach to degrade wastewater and produce hydrogen from water splitting, has been widely used in the field of energy conservation and pollution reduction. However, these hard‐to‐recycle powders pose a challenge of secondary pollution in the environment. As a result, this paper provides an alternative strategy based on the manufacture of porous ceramics as a green chemistry approach to replace ferroelectric powders currently used in traditional piezo‐catalysis. The piezo‐catalytic properties of Ba0.75Sr0.25TiO3 (BST) ceramics prepared using freeze casting and direct ink writing techniques are investigated in detail. The positive effect of introducing micro‐ and macro‐pores is explored and discovered, where a BST ceramic with hierarchical pore channels is prepared by a combination of direct ink writing and freeze casting and exhibts the highest first‐order kinetic rate constant per mass of catalysts, k, of up to 2.91 min−1 kg−1 compared to bulk BST ceramics. This study therefore provides the first report for the benefits of hierarchical porous ferroelectric ceramics used in water splitting, with an average H2 production rate reaching 848.88 nmol g−1 h−1. [ABSTRACT FROM AUTHOR]

Hydrothermally synthesized Nd-doped bismuth titanate (Bi3.15Nd0.85Ti3O12, BIT-Nd) hierarchical microspheres with assembled nanosheets were developed for water splitting and wastewater purification utilizing the piezo-phototronic effect for the first time. Undoped Bi4Ti3O12 (BIT) microspheres were simultaneously studied for comparison to reveal the role of Nd doping. Under the combined light and ultrasound excitation, the degradation efficiency of RhB (C0 = 10 mg L−1) solution reached 97.5% in 8 minutes in the presence of the BIT-Nd microspheres, leading to an ultrahigh first-order rate constant k of 0.407 min−1, which was 4.9 times higher than that of the BIT microspheres. More impressively, superior piezo-photocatalytic activity in water splitting compared to that of other reported piezo-photocatalysts was achieved in the BIT-Nd microspheres, which showed a H2 evolution rate of 1330.3 μmol g−1 h−1 without any cocatalyst or scavenger. To understand the origins of the excellent piezo-photocatalytic performance, microstructure analysis and piezoelectric and photoelectric characterization, as well as density functional theory calculations were carried out. After Nd doping, the atomic framework of the Ti–O octahedron underwent an apparent distortion, resulting in a stronger ferroelectric polarization, and thus a larger piezoelectric potential output under pressure. Moreover, the thinner nanosheets in the BIT-Nd microspheres were more susceptible to deformation under the ultrasonic effect, which was also beneficial to generate a higher piezoelectric field that inhibited the charge carrier recombination. Additionally, the presence of Nd 4f orbitals in BIT-Nd effectively reduced the band gap and promoted the spectral absorption and production of photogenerated carriers. These merits enabled the BIT-Nd microspheres to exhibit strong piezo-photocatalytic activity. [ABSTRACT FROM AUTHOR]

In this paper, the form factors of D(s) to light tensor mesons a2(1320), K 2 ∗ (1 4 3 0) , f 2 (1 2 7 0) , f 2 ′ (1 5 2 5) and corresponding semileptonic decays are investigated through the method of light cone sum rules (LCSR) in the framework of heavy quark effective field theory (HQEFT). Considering the light cone distribution amplitudes (DAs) of tensor mesons to twist-3, we give numerical results of form factors systematically, which are necessary inputs for the analysis of relevant D(s) decays. Based on the form factor results, the relevant semileptonic decays induced by charged current (CC) as well as flavor changing neutral current (FCNC) are studied. Our predictions for the branching ratios, longitudinal polarization fractions and forward–backward asymmetries can be tested by more precise experiments such as LHCb, BESIII and BelleII in the future. [ABSTRACT FROM AUTHOR]

To date, a number of studies have reported the use of vibrations coupled to ferroelectric materials for water splitting. However, producing a stable particle suspension for high efficiency and long‐term stability remains a challenge. Here, the first report of the production of a nanofluidic BaTiO3 suspension containing a mixture of cubic and tetragonal phases that splits water under ultrasound is provided. The BaTiO3 particle size reduces from approximately 400 nm to approximately 150 nm during the application of ultrasound and the fine‐scale nature of the particulates leads to the formation of a stable nanofluid consisting of BaTiO3 particles suspended as a nanofluid. Long‐term testing demonstrates repeatable H2 evolution over 4 days with a continuous 24 h period of stable catalysis. A maximum rate of H2 evolution is found to be 270 mmol h–1 g–1 for a loading of 5 mg l–1 of BaTiO3 in 10% MeOH/H2O. This work indicates the potential of harnessing vibrations for water splitting in functional materials and is the first demonstration of exploiting a ferroelectric nanofluid for stable water splitting, which leads to the highest efficiency of piezoelectrically driven water splitting reported to date. [ABSTRACT FROM AUTHOR]

As both major macronutrients and signal molecules, nitrogen metabolites, such as nitrate and nitrite, play an important role in plant growth and development. In this study, the callus growth of indica rice cv. 9311 was significantly enhanced by nitrite, whereas the soluble protein content remained unchanged. The deep RNA sequencing technology (RNA-seq) showed that the transcriptional profiles of cv. 9311 calli were significantly changed after adding nitrite to the nitrate-free medium, and these nitrite-responsive genes were involved in a wide range of plant processes, particularly in the secondary metabolite pathways. Interestingly, most of the genes involved in phenylpropanoid-related pathways were coordinately down-regulated by nitrite, such as four cinnamoyl-CoA reductase, and these in turn resulted in the decrease of lignin content of indica calli. Furthermore, several candidate genes related to cell growth or stress responses were identified, such as genes coding for expansins, SMALL AUXIN UP RNA (SAUR) and HSP20s, and these suggested that nitrite could probably serve as a transcriptome signal to enhance the indica calli growth by regulation of various downstream genes expression. This study contributes to a better understanding of the function of nitrite during the process of plant tissue culture and could aid in the application of this technology to improved indica genetic transformation efficiency. [ABSTRACT FROM AUTHOR]

Ubiquitous noise pollution has been associated with significant negative impacts on human health. However, current porous sound‐absorbing materials encounter considerable obstacles such as thick density, narrow absorbing band, and limited function. Here, a facile‐producing method for lightweight and efficiently sound‐absorbing aerogels made from bacterial cellulose (BC) and poly(vinyl alcohol) (PVA) is presented. The fabricated anisotropic aerogels with directional pores exhibit a minimum density as low as 11.3 mg cm−3. Meanwhile, the lamellar aerogels with low areal density (20.89 mg cm−2) exhibit remarkable noise attenuation performance with the noise reduction coefficient of 0.51.Furthermore, the BC‐PVA‐Ba0.85Ca0.15Zr0.9Ti0.1O3 (BCZT) aerogels show enhanced sound absorption performance, and these aerogels are self‐powered sensors to monitor vehicle collisions and human gestures. The algorithm yields high accuracy in human gesture recognition (100%) based on the deep‐learning model. These aerogels offer an encouraging application prospect in the automobile field to realize car weight reduction and vehicle's intelligent control system. [ABSTRACT FROM AUTHOR]