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61.
62.
Mango fruit has high commercial value; however, major postharvest losses are encountered throughout the supply chain due to postharvest diseases. These results lead to the search for natural fungicide for postharvest diseases control. The antifungal effects of five essential oils (thyme, clove, cinnamon, anise and vitex) were assessed by disc volatilisation method. Thyme oil vapours at 5 μL per Petriplate, and clove and cinnamon oil at 8 μL per Petriplate showed 100% growth inhibition of mango pathogens in vitro. GC/MS analysis of essential oil showed thymol (23.88), o‐cymol (23.88) and terpinolene (23.88) as the major constituents of thyme oil. Clove and cinnamon oils contain 3‐allyl‐2‐methoxyphenol (37.42%) and benzofuran 3‐methyl (17.97%), respectively. Thyme oil as a fumigant at 66.7 μL L?1 showed a significant (P < 0.05) inhibition on postharvest pathogens of mango fruits stored at 25 °C for 6 days. Results of our study suggest the possibility of using thyme oil as an alternate natural fungicide to manage postharvest diseases in mango.  相似文献   
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64.
Multimedia Tools and Applications - Robust tracking of moving objects is still an open problem in computer vision. The problem and its difficulty depend on many factors, which includes the...  相似文献   
65.
Data-set of monthly global solar irradiance covering periods of at least 20 years over selected stations in Nigeria have been utilised to investigate the sky optical conditions over the five major vegetation zones of the country. The monthly variation of the clearness index for the selected stations has been investigated. Results show that the clearness index has its minimum in August which indicates reduced insolation during the monsoon month of August and maximum around November, December and February which shows high insolation. Statistical analysis of the monthly clearness index which gives the percentage depletion by the sky of the incoming insolation and the subsequent characterisation of the sky conditions based on this were also done. The results show that cloudy sky conditions prevail in the rainforest and mangrove swamp zones (e.g. Lagos, KT=0.40) while clear sky conditions prevail in the Sudan and Sahel vegetation (e.g. Nguru KT=0.66) and Kano (KT=0.65).  相似文献   
66.
The cover image is based on the Research Article Modelling concentration gradients in fed-batch cultivations of E. coli - towards the flexible design of scale-down experiments by Emmanuel Anane et al., DOI: 10.1002/jctb.5798 .

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67.
In this paper, we deal with some magnetostatic models considered in vector potential formulations and solved by a Finite Element solver. In order to ensure the uniqueness of the solution, a gauge condition has to be imposed, and several possibilities occur. Moreover, the source term has to be correctly defined to ensure a physically admissible solution. We show the equivalence between some of these choices for several kinds of boundary conditions. Moreover, we highlight their characteristic behaviors on some numerical benchmarks to illustrate our theoretical results.  相似文献   
68.
Several conditions are proposed to check different robustness properties (ISS, iISS, IOSS and OSS) for generic nonlinear systems applying the weighted homogeneity concept (global or local). The advantages of this result are that, under some mild conditions, the system robustness can be established as a function of the degree of homogeneity.  相似文献   
69.
Beyond the catalytic activity of nanocatalysts, the support with architectural design and explicit boundary could also promote the overall performance through improving the diffusion process, highlighting additional support for the morphology-dependent activity. To delineate this, herein, a novel mazelike-reactor framework, namely multi-voids mesoporous silica sphere (MVmSiO2), is carved through a top-down approach by endowing core-shell porosity premade Stöber SiO2 spheres. The precisely-engineered MVmSiO2 with peripheral one-dimensional pores in the shell and interconnecting compartmented voids in the core region is simulated to prove combined hierarchical and structural superiority over its analogous counterparts. Supported with CuZn-based alloys, mazelike MVmSiO2 nanoreactor experimentally demonstrated its expected workability in model gas-phase CO2 hydrogenation reaction where enhanced CO2 activity, good methanol yield, and more importantly, a prolonged stable performance are realized. While tuning the nanoreactor composition besides morphology optimization could further increase the catalytic performance, it is accentuated that the morphological architecture of support further boosts the reaction performance apart from comprehensive compositional optimization. In addition to the found morphological restraints and size-confinement effects imposed by MVmSiO2, active sites of catalysts are also investigated by exploring the size difference of the confined CuZn alloy nanoparticles in CO2 hydrogenation employing both in-situ experimental characterizations and density functional theory calculations.  相似文献   
70.
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