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The phase-transition behavior and thermal stability of Ge2Sb2Te5/Si nano-multilayered films are investigated in this study. Our results reveal that the improvement in thermal stability and increase in the phase-transition temperature are not universal results for all nano-multilayered structures. The stress effect induced by thermal expansion during heating indeed could inhibit the crystallization of Ge2Sb2Te5/Si nano-multilayered films. The interface effect is believed to play a dominant role in thicker films, while the stress effect is active when the layer thickness is decreased. The gradual shift in the Raman peaks' position can support this scenario because they are modified by both the interface effect and the stress effect. [ABSTRACT FROM AUTHOR]

The phase-transition behavior and thermal stability of Ge2Sb2Te5/Si nano-multilayered films are investigated in this study. Our results reveal that the improvement in thermal stability and increase in the phase-transition temperature are not universal results for all nano-multilayered structures. The stress effect induced by thermal expansion during heating indeed could inhibit the crystallization of Ge2Sb2Te5/Si nano-multilayered films. The interface effect is believed to play a dominant role in thicker films, while the stress effect is active when the layer thickness is decreased. The gradual shift in the Raman peaks' position can support this scenario because they are modified by both the interface effect and the stress effect. [ABSTRACT FROM AUTHOR]

Alluvial fan is an important recharge area for arid and semi-arid inland basins. In order to study groundwater circulation and quantify recharge amount of the groundwater system in arid inland basins, it is necessary to use numerical models. In this study, a 2D variably saturated numerical model of a typical profile has been developed using EOS 9 module of TOUGH2. The mesh for the fine soil plain area was refined compared with previous studies and the minimum cell size was 0.1 m in thickness. An improved approach in TOUGH2 was applied to calculate the groundwater evapotranspiration more efficiently and characterize water transport more accurately. Multiple calibration approaches were combined to calibrate the model. The results show that, the typical profile can be divided into three groundwater flow systems. The circulation depth for the local groundwater flow system is about 200 m and the shallow discharge accounts for 74.4% of the total amount with groundwater age less than 500 a (year). The circulation depth for the middle flow system can reach 800 m and the amount of discharge accounts for 18.5% of the total amount with groundwater age less than 10 ka (kiloyear). The circulation depth for the regional flow system is from 1000 to 1500 m, and the discharge accounts for 7.1% of the total amount with groundwater age ranging from 10 to 50 ka. The improved TOUGH2 numerical model, combined with multiple calibration approaches, can better reflect regional circulation characteristics and quantify the recharge amount of different groundwater sub-systems in arid and semi-arid inland basins with limited datasets. [ABSTRACT FROM AUTHOR]

An immediate quenching using liquid N2 is applied for synthesizing the 5d transitionmetal oxides (Sr1-xCax)2IrO4 (0 ≤ x ≤ 0.15) single phase. X-ray diffraction together with Rietveld refinement shows that the lattice parameters along a and c directions and the bond angle of Ir-O2-Ir decrease with the increase of Ca content. X-ray Absorption Fine Spectroscopy measurements prove that the valence of Ir and the average Ir-O bond-length substantially remain unchanged with Ca content increasing in the phase. The effective magnetic moment μeff and Néel temperature TN decrease simultaneously with increased Ca content. Electrical resistivity shows complex temperature dependence behavior, which follows the three-dimensional variable range hopping behavior at low temperature, Arrhenius-type behavior at middle-temperature, and a weak electronic localization in quasi-two-dimensional at high temperature. [ABSTRACT FROM AUTHOR]

Selective acylation and sulfonylation of 4,6-O-benzylidene-1-deoxy-1-(2-oxo-2-phenylethyl)-β-D-glucopyranose were systematically studied by introducing different electrophiles under the action of catalysts DMAP or Ag2O. As a result, 18 novel mono-protected compounds at the 2- or 3-position of the C-glucoside were prepared and their structures were confirmed by ¹H-NMR, 13C-NMR, 2D NOEs and HRMS analysis. The results showed that electrophiles play a significant role in determining the product distribution. [ABSTRACT FROM AUTHOR]

Hemp seed oil has good sun protection, repair, anti-allergy and anti-aging effects, and is a high quality raw material for the production of skincare products. However, the influence of surfactants and co-surfactants on the emulsification of hemp seed oil in aqueous solution has been rarely investigated. In this investigation, the surfactants and co-surfactants which were suitable for hemp seed oil emulsion were optimized, and the factors which influence the particle size and the stability of the emulsion were studied. Moreover, the application of hemp seed emulsion in different cosmetics was also further investigated. It was found that sorbitan monooleate/polysorbate-80 and glyceryl stearate were the most effective surfactant and co-surfactant in the emulsification of hemp seed oil. After three months the hemp seed oil emulsion had no layered separation and remained homogeneous at -4 °C, 25 °C and 40 °C. The water-resistant sunscreens and the hemp seed oil sunscreens were homogeneous pastes, had a soft texture and were stable at higher temperatures. No microorganisms were detected in these cosmetic creams. Therefore, hemp seed oil is suitable for sunscreen cosmetic materials. [ABSTRACT FROM AUTHOR]

Hemp seed oil has a very better effect of sunscreen, repair, anti-allergy and anti-aging, as a result of which it is a high-quality raw material for skin care products. In this study, the oxidation degree of hot-pressed and cold-pressed hemp seed oil which was stored in five different environments, was evaluated. The results showed that the long-chain unsaturated fatty acids were oxidized. The oxidation products of hemp seed oil were analyzed by headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC/MS) and high performance liquid chromatography (HPLC). All hemp seed oils which were stored at low-temperature protected from light and outdoor environment contained aldehydes, ketones, and alcohols, which have a negative impact on the health of consumers. Furthermore, hemp seed emulsion was prepared with different HLB values. After the 2nd month, hemp seed oil emulsion exhibited a good stability without stratification. [ABSTRACT FROM AUTHOR]

Background: Lycium barbarum polysaccharide (LBP) is a promising therapeutic drug in inflammation-related injuries, nevertheless the mechanism of LBP's action is still elusive. The study is to explore the effect of LBP on IL-1β-evoked ATDC5 cell inflammatory injury. Methods: ATDC5 cells were administrated with 10 ng/mL interleukin (IL)-1β to establish an in vitro model of cartilage damage. After management, cell viability was tested through CCK8 assay. The pro-inflammatory cytokines and cyclooxygenase (Cox)-2 were assessed through ELISA, western blot and qRT-PCR. MiR-124 expression in ATDC5 cells was silenced by transfecting with miR-124 inhibitor, and the pro-inflammatory cytokines and Cox-2 were re-assessed. NF-κB and JNK pathways were measured through western blot. Results: IL-1β stimulation accelerated the release of IL-1β, IL-6 and TNF-α, elevated Cox-2 expression. LBP significantly eased IL-1β-induced inflammation. MiR-124 expression was observed to enhance by LBP, and the impacts of LBP on ATDC5 cells were lightened via transfection with miR-124 inhibitor. NF-κB and JNK pathways were activated after IL-1β stimulation, nevertheless were inactivated by LBP administration. Besides, LBP-evoked the repression of NF-κB and JNK pathways were overturned by miR-124 inhibitor. Conclusions: Our study suggests that LBP protects ATDC5 cells from IL-1β-evoked injury through up-regulating miR-124 via blocking NF-κB and JNK pathways. [ABSTRACT FROM AUTHOR]

Fast and nondestructive detection of early decay caused by fungal infection in citrus fruit was a challenging task for the citrus industry during the postharvest fruit processing. In general, workers relied on the ultraviolet induction fluorescence technique to detect and remove the decayed citrus fruits in fruit packing houses. However, this operation was harmful for human health, and was also very inefficient. In this study, navel oranges were used as research object. A novel method combining with hyperspectral imaging technology in the wavelength region between 400 and 1100 nm wavelength was proposed to solve this problem. First, normalization approaches were applied to decrease the variation of spectral reflectance intensity due to natural curvature of navel orange surface. Then, the spectral data of regions of interest (ROIs) from normal and decayed tissues was analyzed by principal component analysis (PCA) for investigating the performance of visible and near infrared (Vis-NIR) hyperspectral data to discriminate these two kinds of tissues. Next, six characteristic wavelength images were obtained by analyzing the loadings of the first principal component (PC1). And, a multispectral image was established by using the corrected six characteristic wavelength images. On basis of the multispectral image, pseudo-color image processing with intensity slicing was utilized to produce a two-dimensional color image with clear contrast between decayed and normal tissues. Finally, an image segmentation algorithm by combining the pseudo-color processing method and a global threshold method was proposed for fast identification of decayed navel oranges. For 240 independent samples, the success rates were 100 and 97.5% for decayed navel oranges infected by Penicillium digitatum and normal navel oranges, respectively. In particular, the proposed algorithm was also applied to detect the decayed navel oranges infected by Penicillium italicum (samples not used for the development of algorithm) and obtained a 91.7% identification accuracy, indicating a well generalization ability and actual application value of the proposed algorithm. [ABSTRACT FROM AUTHOR]

In this paper, we reported an extremely large out-of-plane/in-plane anisotropic transport ( ~ 109) in double layer ruthenates. The mechanism that may be responsible for this phenomenon is also explored here. Distinct from previously well studied layered materials which show large out-of-plane/in-plane electronic anisotropy (103–106), the Ti-doped Ca3Ru2O7 single crystals not only form quasi-2D layered structure, but also show phase separation within the layers. We found that Ti doping in Ca3Ru2O7 induced electronic phase separation between the insulating phase and weak localized phase. The ratio of these two phases is very sensitive to the Ti concentration. At typical concentration, the weak localized phase may form a channel on the background of the insulating phase within the ab plane. However, the small volume of weak localized phase makes it less likely to overlap in different layers. This results in a much larger electronic anisotropy ratio than pristine compound Ca3Ru2O7. This new mechanism provides a route for further increase electronic anisotropy, which will remarkably reduce current leak and power consumption in electronic devices. [ABSTRACT FROM AUTHOR]