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排序方式: 共有275条查询结果,搜索用时 101 毫秒
1.
Hicham Jediyi Khalid Naamani Abderrahim Ait Elkoch Abdelhey Dihazi Naima Lemjiber 《Journal of Food Safety》2020,40(2):e12756
Vitis vinifera (L) crops, covers an area of about 54,000 ha corresponding to a production of 230,000 t of grapes, representing 5.5% of the national perennial corps. However, this plant is sensitive to various ravages and diseases, among others, the cryptogrammic by fungi. The degrading enzymes of the cell wall are among the factors of pathogenicity the more important than fungi use to colonize their host plants. In this study, the first step was devoted to the antioxidant activity and phenols composition (phenylalanine-ammonia-lyase [PAL], tyrosine-ammonia-lyase [TAL], flavonoids, and tannins) as well as high-performance liquid chromatography analysis in five vineyard leaves extract, which are “Superior, Early sweet and Flame” (Allochthonous), “Abbou and Adari” (endemic). In the second step, the lytic activities “pectinase, polygalacturonase, xylanase, mannanase, glucanase, and cellulase” were investigated among six epiphytic fungus to compare their hydrolytic aggressiveness. Subsequently, as a third part, phenols antifungal potency and Trichoderma biocontrol were displayed in the study. The phenolic compounds observed in the attributes leaves were different among varieties (p < .05), and show that the endemic variety “Abbou” leads the phytochemical amount, which has the highest quantities of PAL, and TAL, as well as the DPPH and FRAP antioxidant activity, while the introduced variety show a higher amount in total phenol and flavonoids. The polygalacturonase, mannanase, and pectinase activities are probably the main factors responsible for the aggressiveness of the studied fungus. Phenols potency showed a good mycelial inhibition with 82.09% as compared to the biocontrol (64.45%). Given the efficacy of the phytochemical control in this study, the phenols could be a part of integrated management strategies for sustainable control of vineyard disease. 相似文献
2.
Abderrahim Titi Mouslim Messali Rachid Touzani Mohammed Fettouhi Abdelkader Zarrouk Nabil Al-Zaqri Ali Alsalme Fahad A. Alharthi Amjad Alsyahi Ismail Warad 《International journal of molecular sciences》2020,21(22)
A new double-open-cubane core Cd(II)-O-Cu(II) bimetallic ligand mixed cluster of type [Cl2Cu4Cd2(NNO)6(NN)2(NO3)2].CH3CN was made available in EtOH/CH3CN solution. The 1-hydroxymethyl-3,5-dimethylpyrazole (NNOH) and 3,5-dimethylpyrazole (NNH) act as N,O-polydentate anion ligands in coordinating the Cu(II) and Cd(II) centers. The structure of the cluster in the solid state was proved by XRD study and confirmed in the liquid state by UV-vis analysis. The XRD result supported the construction of two octahedral and one square pyramid geometries types around the four Cu(II) centers and only octahedral geometry around Cd(II) two centers. Interestingly, NNOH ligand acts as a tetra-µ3-oxo and tri-µ2-oxo ligand; meanwhile, the N-N in NNH acts as classical bidentate anion/neutral ligands. The interactions in the lattice were detected experimentally by the XRD-packing result and computed via Hirschfeld surface analysis (HSA). The UV-vis., FT-IR and Energy Dispersive X-ray (EDX), supported the desired double-open cubane cluster composition. The oxidation potential of the desired cluster was evaluated using a 3,5-DTB-catechol 3,5-DTB-quinone as a catecholase model reaction. 相似文献
3.
International Journal of Steel Structures - The use of FRP composites as external confinement has recently become a very important system to consider when reinforcing concrete and steel structures.... 相似文献
4.
Shiqiao Meng Zhiyuan Gao Ying Zhou Bin He Abderrahim Djerrad 《Computer-Aided Civil and Infrastructure Engineering》2023,38(7):849-872
Real-time automated drone-based crack detection can be used for efficient building damage assessment. This paper proposes an automated real-time crack detection method based on a drone. Using a lightweight classification algorithm, a lightweight segmentation algorithm, a high-precision segmentation algorithm, and a crack width measurement algorithm, the cracks are classified, roughly segmented, finely segmented, and the maximum width is extracted. A crack information-assisted drone flight automatic control algorithm for automatic crack detection guides the drone toward the crack position. The effectiveness of the crack detection algorithm and the crack information-assisted drone flight automatic control algorithm was tested on two different datasets, a two-story building, and a 16-m-high shaking table test building. The results show that crack detection can be finished in real-time during the flight. Using the proposed method can significantly improve the MIoU of crack edge detection and the accuracy of maximum crack width measurement under the non-ideal shooting conditions of the actual inspection situation by automatically approaching the vicinity of the crack. 相似文献
5.
Ashoka Bali Il-Ho Kim Peter Rogl Ramesh Chandra Mallik 《Journal of Electronic Materials》2014,43(6):1630-1638
The thermoelectric figure of merit (zT) can be increased by introduction of additional interfaces in the bulk to reduce the thermal conductivity. In this work, PbTe with a dispersed indium (In) phase was synthesized by a matrix encapsulation technique for different In concentrations. x-Ray diffraction analysis showed single-phase PbTe with In secondary phase. Rietveld analysis did not show In substitution at either the Pb or Te site, and this was further confirmed by room-temperature Raman data. Low-magnification (~1500×) scanning electron microscopy images showed micrometer-sized In dispersed throughout the PbTe matrix, while at high magnification (150,000×) an agglomeration of PbTe particles in the hot-pressed samples could be seen. The electrical resistivity (ρ) and Seebeck coefficient (S) were measured from 300 K to 723 K. Negative Seebeck values showed all the samples to be n-type. A systematic increase in resistivity and higher Seebeck coefficient values with increasing In content indicated the role of PbTe-In interfaces in the scattering of electrons. This was further confirmed by the thermal conductivity (κ), measured from 423 K to 723 K, where a greater reduction in the electronic as compared with the lattice contribution was found for In-added samples. It was found that, despite the high lattice mismatch at the PbTe-In interface, phonons were not scattered as effectively as electrons. The highest zT obtained was 0.78 at 723 K for the sample with the lowest In content. 相似文献
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8.
Ahcene Sadi Abderrahim Elmoataz Matthieu Toutain 《Signal, Image and Video Processing》2016,10(3):439-446
This paper presents an adaptation and extension of the shock filters on weighted graphs using the formalism of partial difference equations. This adaptation leads to new morphological operators that alternate between nonlocal dilation and nonlocal erosion filter type on graphs. Furthermore, this adaptation extends the shock filter applications to any data that can be represented by graphs. This approach is illustrated through image, data defined on region maps, and 3D point cloud processing. 相似文献
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10.
Effect of supercritical CO2 extraction process parameters on oil yield and pigment content from by‐product hemp cake 下载免费PDF全文
Krunoslav Aladić Senka Vidović Jelena Vladić Davor Balić Huska Jukić Stela Jokić 《International Journal of Food Science & Technology》2016,51(4):885-893
This research gives an insight into the possibility of exploiting the one of the food industry's by‐products – pressed hemp cake. The complete recovery of oil from pressed hemp cake was achieved. Residual oil that remained in cake after pressing was extracted with supercritical CO2 by applying different process parameters. Optimal extraction conditions were determined using response surface methodology. Total pigment contents of the oils obtained were determined. Extraction pressure had the most significant influence on yield and pigment content of extracted hemp cake oil. Depending on the pressure, the chlorophyll a content ranged from 101.11 to 378.28 mg kg?1 and chlorophyll b from 65.14 to 189.78 mg kg?1, while total carotene content was in the range from 33.58 to 132.67 mg kg?1. The remaining oil in pressed hemp cake after supercritical CO2 extraction was determined to be 0.56 ± 0.08% and the defatted cake was rich in proteins and fibre. 相似文献