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Bulletin of Engineering Geology and the Environment - Although soil-lime treatment has been successfully used for a long time, the mechanisms behind the clay soil-lime reaction remain...  相似文献   
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Wheat (Triticum aestivum L.) is the most important staple food crop globally. According to economic survey 2018‐19, agriculture sector of Pakistan grew by 0.85%, with wheat accounting for 8.9% of agriculture and 1.6% of GDP, and its production fell short of the target by 4.9%. Wheat requires beneficial ties to improve its efficiency with the help of modern technology. Nanotechnology modifies conventional agricultural practices as these are stimulating agents for plant growth. Green bimetallic Ag/ZnO alloy nanoparticles (NPs) synthesised from salts reduced by Moringa oleifera and characterised by UV‐visible spectroscopy, scanning electron microscopy, and energy‐dispersive X‐ray spectroscopy are studied herein. Different concentrations of urea and Ag/ZnO alloy NPs were applied exogenously to wheat plants (Pakistan‐13 and Galaxy13). A significant effect of 100 mg/L urea and 75 ppm Ag/ZnO alloy NPs was observed on the morphology of wheat, with a maximum increase of 58% plant length, 85% leaf area, 89% plant fresh weight and 76% plant dried weight. In physiological parameters, relative water content and membrane stability index have shown maximum increases of 39% and 77%, while chlorophyll a, b, and total chlorophyll content (TCC) showed maximum increases of 92%, 71%, and 84% respectively. Evidence of the morpho‐physiological responses of urea and green synthesised alloy NPs on wheat varieties are reported on.  相似文献   
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The swelling process of poly(n‐butyl acrylate/1,6‐hexane‐diol‐di‐acrylate) [Poly(Abu/HDDA)] networks, immersed in a liquid crystalline (LC) solvent, was investigated in order to obtain improved swelling ratio values upon application of an original method using a central composite design. The polymer/LC systems under investigation were elaborated via a photopolymerization/crosslinking phase separation process induced by UV radiation of initial mixtures composed of mono‐ and bifunctional monomers, a photoinitiator, and the low‐molar‐weight nematic LC blend E7. The parameters which strongly impact the swelling behavior of Poly(Abu/HDDA)/E7 systems were identified as temperature and concentration of the bifunctional monomer in the initial photopolymerizable mixture, thus controlling the crosslinking density of the final polymer network. The existence of interactions and synergies between these two parameters were also examined. The quality of the model was verified by a good agreement between experimental results and predicted response. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45230.  相似文献   
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The dynamic swelling behavior of chemically crosslinked poly(n‐butylacrylate/1,6‐hexanedioldiacrylate) [poly(Abu‐HDDA)] networks, immersed in an nematogenic and two isotropic solvents, was experimentally analyzed. These networks were elaborated by ultraviolet (UV)–visible light‐induced radical polymerization/crosslinking reactions of Abu/HDDA mixtures, to yield poly(Abu/0.5 wt % HDDA) and poly(Abu/5 wt % HDDA) networks corresponding to weakly and strongly crosslinked systems, respectively. The swelling behavior of these poly(Abu‐HDDA) networks was investigated by immersion in excess solvent, followed by subsequent measurements of the variation of the sample size by means of optical microscopy, depending on temperature and immersion time. Methanol and toluene were employed as isotropic solvents and the nematic liquid crystal molecule 4‐cyano‐4 ′ ‐n‐pentyl‐biphenyl, was considered as anisotropic medium. Swelling ratios were calculated by taking into account diameter sizes as function of immersion time compared to the dry state. Experimental data were analyzed using the Komori–Sakamoto approach and the results of this model were found to be in good agreement with the obtained data. The plateau values of the swelling curves at equilibrium were used to establish phase diagrams as function of temperature and solvent concentration. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45452.  相似文献   
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Cancer is a major cause of death worldwide. Epigenetic changes in response to external (diet, sports activities, etc.) and internal events are increasingly implicated in tumor initiation and progression. In this review, we focused on post-translational changes in histones and, more particularly, the tri methylation of lysine from histone 3 (H3K27me3) mark, a repressive epigenetic mark often under- or overexpressed in a wide range of cancers. Two actors regulate H3K27 methylation: Jumonji Domain-Containing Protein 3 demethylase (JMJD3) and Enhancer of zeste homolog 2 (EZH2) methyltransferase. A number of studies have highlighted the deregulation of these actors, which is why this scientific review will focus on the role of JMJD3 and, consequently, H3K27me3 in cancer development. Data on JMJD3’s involvement in cancer are classified by cancer type: nervous system, prostate, blood, colorectal, breast, lung, liver, ovarian, and gastric cancers.  相似文献   
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A series of Ti0.9Fe0.1-xNixO2 (x?=?0.0, 0.02, 0.04, 0.06, 0.08, 0.1) has been synthesized through the solid state reaction method at annealing temperature of 1100?°C for two hours. The synthesized samples have been analyzed by X-Ray diffractometer (XRD), Raman spectroscopy, Scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDX), Vibrating sample magnetometer (VSM) and ultraviolet visible (UV–VIS) spectroscopy for structural investigations, defects measurements, surface morphology, magnetic and optical properties respectively. Structural analysis has revealed the dominant structure of rutile. An intensity loss and peak broadening of TiO2 (rutile) vibration lines have been observed from Raman analysis, which is an indication of presence of oxygen vacancies. Magnetic analysis has revealed ferromagnetic behavior at room temperature. Optical characterization has shown the blue shift in band gap energy with increase of Ni concentration.  相似文献   
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Chemical composition and antioxidant activity of Salvia officinalis essential oil (EO) were studied under different drying methods of plant material. Results obtained showed that dried plant material yielded more essential oils than did the fresh one. The highest EO yields were obtained by infrared drying at 45?°C (0.39%) followed by air drying (0.30%) and oven drying at 45?°C (0.26%). The analysis of EOs by gas chromatography?Cmass spectrometry, showed in each of 55 identified compounds belonging mostly to oxygenated monoterpenes. This class of compounds was significantly affected by following drying methods: oven at 65?°C, microwave (500?W), and infrared at 45?°C. The main components of sage EO, 1,8-cineole, ?? and ??-thujone, camphor, viridiflorol, and manool showed significant variation (p?<?0.05) with drying methods. Their concentrations increased significantly, particularly when drying sage at ambient air. Finally, the screening of antioxidant activity of the different sage EOs using the di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium radical (DPPH) assay showed an appreciable reduction of the stable radical DPPH, although microwave drying was the most efficient method with an IC50 of 1.60% as compared with fresh plant (IC50?=?5.32).  相似文献   
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