Strain engineering on structures and properties in ferroelectric thin films with perovskite structures

The class of Chaplygin gas models regarded as a candidate of dark energy can be realized by a scalar field,which could drive the variation of the fine structure constant α during the cosmic time.This phenomenon has been observed for almost ten years ago from the quasar absorption spectra and attracted many attentions.In this paper, the authors reconstruct the class of Chaplygin gas models to a kind of scalar fields and confront the resulting Δα/α with the observational constraints.It is found that if the present observational value of the equation of state of the dark energy was not exactly equal to -1, various parameters of the class of Chaplygin gas models are allowed to satisfy the observational constraints,as well as the equivalence principle is also respected

Impacts and Demonstration Effects of Applying Long-acting Slow-release Fertilizer on Economic Yield of Peanut

[Objectives] To study the impacts and demonstration effects of long-acting slow-release fertilizer application on economic yield of peanut. [Methods] The 25, 30, 35, 40, 45, 50 kg of long-acting slow-release fertilizers were applied to 667 m2 of peanuts, and different amounts of urea were applied together. [Results] Applying 40 kg of long-acting slow-release fertilizer and 10.45 kg of urea had the best effect. Compared with the application of ordinary compound fertilizers, the plants did not age prematurely, the leaf diseases were mild, the stems and leaves remained dark green when harvested, and the stems and leaves had a longer functional period. Bearing shoots increased by 1.7, single-plant full pods increased by 2.4, double-seed peanuts increased by 3.2, empty pods decreased by 0.5, and single-seed peanuts decreased by 0.7. The experimental demonstration results show that the spring-sowed peanuts had an average yield increase of 29.0-67.2 kg/667 m2, and the yield increase rate was 7.35%-16.89%, and the difference was extremely significant. [Conclusions] In the high-yield cultivation of peanuts, the application of long-acting slow-release fertilizer can be promoted to improve peanut production

Impacts and Demonstration Effects of Applying Long-acting Slow-release Fertilizer on Economic Yield of Peanut

[Objectives] To study the impacts and demonstration effects of long-acting slow-release fertilizer application on economic yield of peanut. [Methods] The 25, 30, 35, 40, 45, 50 kg of long-acting slow-release fertilizers were applied to 667 m2 of peanuts, and different amounts of urea were applied together. [Results] Applying 40 kg of long-acting slow-release fertilizer and 10.45 kg of urea had the best effect. Compared with the application of ordinary compound fertilizers, the plants did not age prematurely, the leaf diseases were mild, the stems and leaves remained dark green when harvested, and the stems and leaves had a longer functional period. Bearing shoots increased by 1.7, single-plant full pods increased by 2.4, double-seed peanuts increased by 3.2, empty pods decreased by 0.5, and single-seed peanuts decreased by 0.7. The experimental demonstration results show that the spring-sowed peanuts had an average yield increase of 29.0-67.2 kg/667 m2, and the yield increase rate was 7.35%-16.89%, and the difference was extremely significant. [Conclusions] In the high-yield cultivation of peanuts, the application of long-acting slow-release fertilizer can be promoted to improve peanut production

Improved Pyroelectric Properties of CaBi4Ti4O15 Ferroelectrics Ceramics by Nb/Mn Co-Doping for Pyrosensors

The pyroelectric properties of Nb(Mn)-doped and Nb/Mn co-doped CaBi4Ti4O15 (CBT) bismuth layer-structured ferroelectric ceramics were investigated. It was found that Nb/Mn co-doping resulted in stronger enhancement of pyroelectric properties than that of single Nb or Mn doping. The mechanism of doping effect was explained by the distortion of the [BO6] octahedra induced by the doped Nb and Mn cations occupying the B-site of the pseudoperovskite structure. A large pyroelectric coefficient of 84.4 μC/m2K was obtained at room temperature for Nb/Mn co-doped CBT (CBTN-Mn) ceramics, higher than that of pure, Nb or Mn-doped counterparts, being on the order of 35.9, 58.2, 44.0 μC/m2K, respectively. The enhanced pyroelectric coefficient together with reduced dielectric constant (99) and dielectric loss (0.002) led to greater improvement of figures of merit (FOMs), including FOMs for voltage responsivity (Fv ~ 3.95 x 10−2 m2/C) and detectivity (Fd ~ 2.44 x 10−5 Pa−1/2), in CBTN-Mn ceramics. Furthermore, the temperature variations of Fv and Fd were found to be 24% and 68%, respectively, over a broad temperature range from room temperature to 350°C, making CBTN-Mn ceramics potential candidate for high-temperature pyroelectric devices

Enhanced piezoelectric properties of Nb and Mn co-doped CaBi4Ti4O15 high temperature piezoceramics

The properties of CaBi4Ti4O15 (CBT), CaBi4Ti3.95Nb0.05O15 (CBTN) and CaBi4Ti3.95Nb0.05O15 + 0.2 wt% MnO2 (CBTN-Mn) ferroelectric ceramics with bismuth layer structure were studied. Significant enhancement of piezoelectric coefficient was obtained for CBTN-Mn ceramics (d33 = 23 pC/N), being nearly three times that of CBT counterpart (d33 = 8 pC/N). Together with its high Curie temperature (Tc = 790 °C), low dielectric loss (tanδ = 0.2%), high resistivity (ρ = 4.2 x 106 Ω cm at 500 °C) and good thermal stability up to 700 °C, the CBTN-Mn ceramic is a potential material for high temperature piezoelectric applications

Pyroelectric properties of rare-earth calcium oxyborate crystals: ReCa 4O(BO3)3 (Re: Y, Gd, Nd, and Pr)

Pyroelectric properties of the monoclinic ReCa 4 O(BO 3 ) 3 (ReCOB, where Re is rare earth: Y, Gd, Nd, and Pr) single crystals were investigated by the charge integration method in the temperature range of 20°C to 180°C. The two independent pyroelectric coefficients p 1 and p 3 were measured and their temperature-dependent properties were studied; the pyroelectric p1 was found to be negative and decrease with increasing temperature, varying from -59.3, -64.2, -65.5, and -59.5 μC/(m 2· °C) at 30°C to -52.9, -53.3, -46.6, and -50.5 μC/(m 2· °C) at 180°C for YCOB, GdCOB, NdCOB, and PrCOB, respectively, whereas the positive coefficient p3 was observed to decrease from 11.6, 13.6, 23.5, and 31.0 μC/(m 2· °C) at 30°C to 2.5, 7.1, 4.9, and 10.1 μC/(m 2· °C) at 180°C, respectively. In addition, the ReCOB crystals were found to possess relatively high detectivity F d , being 7.6 to 11.4 x 10 -5 Pa -1/2 at 30°C, approximately two times that of commercial triglycine sulfate (TGS) and LiTaO 3 crystals, with minimal variations up to 180°C, indicating the potential for use in thermal imaging applications

Microstructure and electrical properties of Nb and Mn co-doped CaBi4Ti4O15 high temperature piezoceramics obtained by two-step sintering

Bismuth layer structural ceramics with a composition of CaBi4Ti3.95Nb0.05O15+0.2 wt% MnO2 (CBTN-Mn) were prepared by a two-step sintering (TSS) approach. The effect of sintering process on the microstructure and its relationship with the electrical properties of the CBTN-Mn ceramics was investigated. A dense microstructure with small and homogeneous grains was obtained under an optimized two-step sintering condition, leading to a strongly enhanced piezoelectric constant (d33=27 pC/N). In addition, this ceramic also possesses high Curie temperature (Tc=790 °C), low dielectric loss (tan δ=0.2%) and high dc resistivity (ρ=5.5x106 Ω cm at 500 °C), indicating its potential for high temperature piezoelectric sensing applications

Comparative Study on the Chemical Components and Gastrointestinal Function on Rats of the Raw Product and Licorice-Simmered Product of Polygala tenuifolia

The root of Polygala tenuifolia Willd. (Polygalaceae) (PT) has been listed as a nootropic, anti-inflammatory, and antipsychotic medicine that can cure insomnia. Raw PT (RPT) is toxic and must be processed before clinical use. Licorice-simmered PT (LPT) is one of the most common processed products. We conducted this study in order to investigate the differences in chemical components and gastrointestinal function between RPT and LPT. We used principal component analysis (PCA) and quantitative analysis to study the differences in the chemical components. Animal experiments were conducted to evaluate the effects of PT on the gastrointestinal function of rats before and after simmering. Pathological sections of gastrointestinal tissues, serum hormone levels, and inflammatory cytokines were observed. The PCA results demonstrated that obvious separation was achieved between the RPT and LPT samples. Tenuifoliside B (TFSB), 3,6’-disinapoyl sucrose (DSS), tenuifoliose A (TFOA), tenuifoliose H (TFOH), onjisaponin B (OJB), onjisaponin Z (OJZ), and total saponins levels were decreased after licorice processing, while glomeratose A (GA) and 3,4,5-trimethoxycinnamic acid (TMCA) levels were markedly increased. Compared to the control group, the RPT groups exhibited dramatically lower levels of gastrin (GAS), motilin (MTL), and substance P (SP) and markedly higher levels of vasoactive intestinal peptide (VIP) and somatostatin (SS), but the LPT groups exhibited no significant differences in the above indexes. The levels of interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-α (TNF-α) in gastrointestinal tissue were markedly increased in the low RPT (L-RPT), high RPT (H-RPT), and H-LPT groups, showing a certain inflammatory effect, but the inflammatory effect in the L-LPT group was relatively weak. Licorice simmering can effectively reduce the inhibitory effect of RPT on gastrointestinal function in rats and reduce damage to gastrointestinal tissue. This study provides a scientific basis for research on the processing mechanism and clinical application of PT