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SUMMARY: ERFs (ethylene‐responsive factors) are known to play a key role in orchestrating cold stress signal transduction. However, the regulatory mechanisms and target genes of most ERFs are far from being well deciphered. In this study, we identified a cold‐induced ERF, designated as PtrERF110, from trifoliate orange (Poncirus trifoliata L. Raf., also known as Citrus trifoliata L.), an elite cold‐hardy plant. PtrERF110 is a nuclear protein with transcriptional activation activity. Overexpression of PtrERF110 remarkably enhanced cold tolerance in lemon (Citrus limon) and tobacco (Nicotiana tabacum), whereas VIGS (virus‐induced gene silencing)‐mediated knockdown of PtrERF110 drastically impaired the cold tolerance. RNA sequence analysis revealed that PtrERF110 overexpression resulted in global transcriptional reprogramming of a range of stress‐responsive genes. Three of the genes, including PtrERD6L16 (early responsive dehydration 6‐like transporters), PtrSPS4 (sucrose phosphate synthase 4), and PtrUGT80B1 (UDP‐glucose: sterol glycosyltransferases 80B1), were confirmed as direct targets of PtrERF110. Consistently, PtrERF110‐overexpressing plants exhibited higher levels of sugars and sterols compared to their wild type counterparts, whereas the VIGS plants had an opposite trend. Exogenous supply of sucrose restored the cold tolerance of PtrERF110‐silencing plants. In addition, knockdown of PtrSPS4, PtrERD6L16, and PtrUGT80B1 substantially impaired the cold tolerance of P. trifoliata. Taken together, our findings indicate that PtrERF110 positively modulates cold tolerance by directly regulating sugar and sterol synthesis through transcriptionally activating PtrERD6L16, PtrSPS4, and PtrUGT80B1. The regulatory modules (ERF110‐ERD6L16/SPS4/UGT80B1) unraveled in this study advance our understanding of the molecular mechanisms underlying sugar and sterol accumulation in plants subjected to cold stress. Significance Statement: The transcription factor ERF110 of Poncirus trifoliata L. Raf. functions positively in cold tolerance due to modulation of sugar and sterol biosynthesis by regulating SPS4, ERD6L16, and UGT80B1. [ABSTRACT FROM AUTHOR]

(Pb0.87La0.02Ba0.1) (Zr0.7Sn0.24Ti0.06)O3 (PLBZST) antiferroelectric ceramics with the addition of 0-9 wt. % excess PbO were fabricated by the conventional solid-state reaction process, and their microstructure, dielectric, and pyroelectric properties were systemically investigated. When excess PbO content was less than 9 wt. %, two pyrochlore phases were formed along with the perovskite phase. Compared with common specimens, PLBZST antiferroelectric ceramics with excess PbO exhibited a higher pyroelectric coefficient and a lower dielectric loss, which are beneficial for the development of pyroelectric devices. Around the Curie temperature, as the excess PbO increased from 0 wt. % to 9 wt. %, PLBZST ceramics' pyroelectric coefficient increased from 1600 μC/m2K to 4000 μC/m2K, and the figure of merit increased from 40 × 10-5 Pa-0.5 to 140 × 10-5 Pa-0.5 under a 400 V/mm dc field. The largest figure of merit of 200 × 10-5 Pa-0.5, which is about 8 times higher than that of conventional phase transition materials barium strontium titanate (BST), was obtained in PLBZST ceramics with 6 wt. % excess PbO when a 600 V/mm dc bias field was applied. Therefore, improvement of pyroelectric property is beneficial for the development of infrared detectors. [ABSTRACT FROM AUTHOR]

The effect of direct-current (dc) biasing on the dielectric properties of porous Ba0.6Sr0.4TiO3 with various porosities, pore sizes, and different pore shapes has been studied in the paraelectric state. The existing model did not consider the effect of the change in grain size and pore shape, lead to the theory fitting the fine grained or nonspherical pore ceramics less well. The bias equation used in this literature to predict the electric field dependence of permittivity is modified by introducing a coefficient α. α is the microstructure parameter introduced to depict the influence of grain size and pore shape effect. Taking high porosity samples and nonspherical pore ceramic samples, for example, the modified bias equation gives a better fit to the experimental result in this study. [ABSTRACT FROM AUTHOR]

Pb0.97La0.02(Zr0.65Sn0.3Ti0.05)O3 (PLZST) antiferroelectric ceramics containing various contents of Ba were fabricated via the conventional solid-state reaction approach, in which the dependence of the microstructure, ferroelectric feature, and energy storage performance and its temperature stability were studied in detail. The findings demonstrate that introducing an appropriate content of Ba is able to not only upgrade the electric polarization as well as the recoverable energy density, but also improve the temperature stability of the energy density in PLZST ceramics. Compared to the PLZST without Ba which has a recoverable density around 1.0 J cm?3, the PLZST added with 6 mol. % Ba possesses a favorable recoverable density of 2.4 J cm?3. Furthermore, the introduction of an adequate content of Ba results in a desirable temperature stability of 90% over a 100 ?C temperature span. We envisage that the systemically investigation of the recoverable energy density and its temperature stability of the antiferroelectric ceramics in this work will benefit the exploration of a high performance of energy-storage technology for the electric power systems. [ABSTRACT FROM PUBLISHER]

Pb[(Mn0.33Nb0.67)1/2(Mn0.33Sb0.67)1/2]0.08(ZrxTi1-x)0.92O3(PMnN-PMS-PZT) pyroelectric ceramics with varied compositions were successfully prepared by the conventional solid state method. The microstructures and electric properties of three different Zr/Ti compositions, i.e. 94/6, 95/5 and 96/4 (in molar ratio) of the ceramics were studied. When x = 0.94, 0.95 and 0.96 in the ceramics, the maximum pyroelectric coefficient peaks appear at 43°C, 28°C and 34°C, and the maximum values are 21.0×10−4C/m2°C, 26.5×10−4C/m2°C and 16.0×10−4C/m2°C, respectively. And the ceramics of the three different Zr/Ti compositions were used to fabricate pyroelectric energy harvesting devices, which were evaluated by using an oven as the heating method. The maximum densities of surface charge achieved for the ceramics of the three compositions are 6.47×10−6C/cm2, 7.19×10−6C/cm2and 4.31×10−6C/cm2, respectively. The obtained results indicate that the PMnN-PMS-PZT ceramic with Zr/Ti of 95/5 in molar ratio exhibits the best pyroelectric and ferroelectric properties, which may have potential applications in fabricating pyroelectric energy harvesting devices. [ABSTRACT FROM AUTHOR]

Antiferroelectric ceramic/polymer composites can be used as a base material in the future application of the tunable photonic crystals even high strain actuators, shock-activated energy transducer and high-density capacitor for their easy fabrication, good flexibility, precise control of the process parameters and good dielectric tenability affected by electric field. The adjustable dielectric effect in the antiferroelectric ceramic/polymer composites are experimentally studied with specific interest in the dependence on the inducing electric field up to 100 V/mm. The particulate composite consisting 20 vol% of polystyrene (PS), 80 vol% of lead barium lanthanum zirconium tin titanate (PBLZST) is fabricated by the means of solution mixing and hot pressing in lab. Scanning electron microscopy was used to investigate the morphology of the composites and the particle distribution, which shows that the nano carbon powders evenly dispersed in composite materials. It is observed that the addition of coupling agent and nano carbon powders influence the dielectric properties, such as the value of the tunability rate of dielectric permittivity and loss tangent. This is partly attributed to coupling agent improve two phase separation and enhanced the effect of ceramic phase in composites, and partly attributed to carbon powders which create electric paths between PBLZST Particles in composite material, which together make more electric field applied to ceramic phase and influence the response of dielectric permittivity controlled by electric field. As a result, the best electric field value to adjust the dielectric permittivity (ε) is 100 V/mm and maximum tunability rate was 49 %, with coupling agent at 10 wt% and nano carbon powders at 1 wt% in composites. [ABSTRACT FROM AUTHOR]

(Pb0.87Ba0.1La0.02)(Zr0.68Sn0.24Ti0.08)O3 ( PBLZST) antiferroelectric ( AFE) ceramics have been prepared by hot-press sintering method and conventional solid-state reaction process, and the dependence of microstructure and energy storage properties of the ceramics on sintering approaches has been studied. The results reveal that not only the microstructure, but also the electrical properties of the PBLZST AFE ceramics are significantly improved by using the hot-press sintering method. Samples resulting from the hot-press sintering process have high breakdown strength of 180 kV/cm which results from the increase of density. Coupled with large polarization, the hot-pressed AFE ceramics are shown to have a high recoverable energy density of 3.2 J/cm3. The recoverable energy density of the hot-pressed PBLZST AFE ceramics is 100% greater than the conventional sintered specimens with recoverable energy density of 1.6 J/cm3. [ABSTRACT FROM AUTHOR]

The β-phase of poly(vinylidene fluoride) (PVDF) is of great technical importance because of its high dielectric constant and piezoelectric effect. In this work, we exfoliated and dispersed natural graphite to prepare 2D-graphite nanosheets (GNS) and prepared PVDF/GNS nanocomposites with different GNS volumes from 1 to 7 ml as film via solution casting method. The concentration of the supernatant was about 0.3 mg/mL. The effect of GNS on the β-phase formation and mechanisms of piezoelectric formation in the PVDF/GNS nanocomposites were investigated. The results showed that with the varying amounts of GNS, the crystalline structure, the morphology, and the dielectric and piezoelectric properties of PVDF/GNS nanocomposites changed. GNS acts as an effective nucleation agent with the orientation almost parallel to the surface of the film meanwhile increasing the amount of beta phase in the PVDF matrix with increasing amount of GNS, also the relative dielectric constant and dielectric loss of the nanocomposites increased with increasing amount of GNS. The value d also increased with increasing amount of GNS, and reached a maximum (6.7 pC/N) with 6 ml GNS. The mechanism of piezoelectric formation was proposed based on experiment results of PVDF/GNS nanocomposites. [ABSTRACT FROM AUTHOR]

(PbLaBa)(ZrSnTi)O (PLBZST, 0.06≤ x≤0.09) antiferroelectric ceramics were fabricated by conventional solid state reaction process, and their ferroelectric, dielectric, and pyroelectric properties were systemically investigated. PLBZST with different Ti content were all confirmed to be in an antiferroelectric phase at T=50°C, which is close to the lowest phase transition temperature. Compared with conventional FE ceramics, PLBZST antiferroelectric ceramics exhibited higher electric field induced pyroelectric coefficient ( p). As the content of Ti increased from 0.06 to 0.09, the pyroelectric coefficient increased from 1000 to 6500 μC/mK under a 500 V/mm DC bias field. The maximum pyroelectric coefficient of 8400 μC/mK was obtained at x=0.09 when an 850 V/mm DC bias field was applied, which is far larger than that of conventional phase transition pyroelectric materials. Large pyroelectric response is beneficial for the development of infrared detectors and thermal imaging sensors. [ABSTRACT FROM AUTHOR]

Graphene as functional layer on flexible polymers for stretchable applications have attracted much research interests, and the fabrication methods are of great importance. In this letter, rapid room temperature and transfer-free fabrication of few-layer graphene on flexible polymer substrates has been realized by rubbing method. This is achieved by the surface fractal evolution rubbing step which can evolve sandpaper surface to form relatively large area of smooth parts as self-lubricated smooth surface. The graphene displayed strong adhesion with flexible polymer substrates, which is benefit for applications. Physical mechanisms of rubbing steps and fabrication of graphene on polymers are studied. [ABSTRACT FROM AUTHOR]

In this letter, a universal ultrafast sandpaper assisting rubbing method was proposed to fabricate two-dimensional nanosheets (graphene, hexagonal boron nitride, tungsten disulfide, molybdenum disulfide) directly on flexible polymer substrate under room temperature. By two steps of rubbing progresses totally within 2 min, raw materials could be evolved to be thinner and to be attached onto polymer substrate. The final products showed high surface stability, which would be very useful during applications, and the physical mechanisms of surface stability were discussed. The micro-morphology evolutions of two-dimensional powders and sandpapers were tested to study the physical mechanisms of the method. [ABSTRACT FROM AUTHOR]

In this letter, we developed an original innovative wiping-rubbing method to fabricate flexible transparent conductive films (TCFs) based on graphene nanosheets. We achieved this by using only commercial graphite block and polycarbonate film as raw materials, through a cost effective and ultrafast room temperature wiping-rubbing process (within 2 min). The properties of our flexible TCFs were competitive when comparing with literature reported graphene TCFs. Our flexible TCFs showed enough surface stability under a series of surface destructive treatments. The physical mechanism aspects of wiping-rubbing processes and surface stability were discussed. [ABSTRACT FROM AUTHOR]

Abstract: (Pb0.97−x La0.02Ba x )(Zr0.75Sn0.12Ti0.13)O3 ceramics in the composition range 0.1≤ x ≤0.16 were prepared by conventional solid state reaction process. On increasing Ba content from 0.1 to 0.16mol, the specimens underwent phase transition from the first order to the second order and the Curie temperature decreased from 85 to 35°C. With x =0.16, the specimen showed good pyroelectric properties for practical applications. When a 500V/mm dc bias field was applied, the specimen showed the maximum pyroelectric coefficient of 5800μC/m2 K and figure of merit of 58×10−5 Pa−0.5 at Curie temperature. [Copyright &y& Elsevier]

The degradation behavior against pulse–current stress and the stability against DC accelerated aging stress of Na 2 CO 3 doped ZnO-based varistor ceramics were investigated in this work. The results showed that the breakdown field E 1 mA / cm 2 and the nonlinear coefficient ( α ) decrease with the increasing of the content of Na 2 CO 3 . The EDX analysis confirmed that the doping of Na ions into ZnO grains can enhance the electron concentration in grains and restrict the migration of zinc interstitials. The varistor with 0.06 mol% Na 2 CO 3 sintered by two-step exhibited the best performance for clamp characteristics and stability against DC accelerated aging stress. The clamping voltage ratio K against pulse–current stress of 3500–5500 A was 2.11–2.29, and the variation rate of the breakdown field ( % Δ E 1 mA / cm 2 ) was only −0.2, in addition, the variation rate of the nonlinear coefficient α was −0.3 for DC accelerated aging stress of 0.9 E 1 mA /120 °C /8 h. [ABSTRACT FROM AUTHOR]

Highlights: [•] We fabricated the high-T C piezoelectric ceramics by the microwave sintering process. [•] The microstructure of the high-T C piezoelectric ceramics has been improved. [•] The piezoelectric properties have been improved by the microwave sintering process. [•] Microwave sintering is an effective method to fabricate piezoelectric ceramics. [Copyright &y& Elsevier]

Abstract: (Pb0.87Ba0.1La0.02)(Zr0.68Sn0.24Ti0.08)O3 anti-ferroelectric ceramics with various amounts of excess PbO have been fabricated by the conventional solid-state reaction process and the hot-press sintering method, and the dependence of microstructure, ferroelectric and dielectric properties on sintering approaches and lead volatilization conditions has been studied. When an appropriate quantity of excess PbO is added, the lead volatilization effect can be compensated and the content of pyrochlore phase is decreased. Hot-pressed anti-ferroelectric ceramics exhibit much higher densities than conventionally sintered samples. The spontaneous polarization and maximum dielectric constant of the AFE ceramics decrease when the hot-press sintering method is used. The dielectric loss can be obviously reduced by using the hot-press sintering method and adding a proper amount of excess PbO. The systemic investigation of the lead volatilization effect and the hot-press sintering method will contribute to the development of high properties of anti-ferroelectric ceramics in practical applications. [Copyright &y& Elsevier]