The micromechanical properties of agricultural products can be used to formulate simulation models and optimize processing parameters for harvest,packaging,and storage.In this study,a detection platform was designed f...The micromechanical properties of agricultural products can be used to formulate simulation models and optimize processing parameters for harvest,packaging,and storage.In this study,a detection platform was designed for conducting mechanical tests on different specimens at the tissue level.The system provided controllable and precise displacements;the relative error was less than±1.0%.The displacement and force measurements were calibrated.Micromechanical tests of apple parenchyma tissues were conducted to evaluate the performance of the proposed platform.The stress-strain curves of the specimens and the micrographs of the microstructures can be obtained simultaneously during the tests.The proposed platform has the capability to test mechanical properties and obtain micro behaviors of agricultural products at the tissue level,which helps in studying the failure mechanism of agricultural products under external loading.展开更多
Most animals, including humans, produce natural sex hormones such as estrogens: 17β-estradiol(E2) and estrone(E1). These compounds are able to disrupt the reproductive systems of living organisms at trace concentrati...Most animals, including humans, produce natural sex hormones such as estrogens: 17β-estradiol(E2) and estrone(E1). These compounds are able to disrupt the reproductive systems of living organisms at trace concentrations(ng·L^(–1)). This experiment tests the hypothesis that 1% slow pyrolysis biochar-amended sandy soil could retain significant amount of estrogens(E1, E2)from poultry manure in its second year of application. The experiment was conducted over 46 days and consisted of a series of lysimeters containing sandy soil with biocharamended topsoil. The application rate of poultry manure was kept at 2.47 kg·m^(–2). The biochar held a significant concentration of hormone during the first year of its application. However, in the following year(current study), there was no significant retention of hormones in the biochar-amended soil. During the first year after application, the biochar was fresh, so its pores were available for hydrophobic interactions and held significant concentration of hormones. As time passed there were several biotic and abiotic changes on the surface of the biochar so that after some physical fragmentation, pores on the surface were no longer available for hydrophobic interactions. The biochar started releasing dissolved organic carbon, which facilitated greater mobility of hormones from poultry manure down the soil profile.展开更多
基金the National Natural Science Foundation of China for the financial support of the project“Study on kinematics and dynamics of pollen and pneumatic pollination method in hybrid rice seed production”(Grant No.31971796)supported by the Earmarked Fund of CARS-01.
文摘The micromechanical properties of agricultural products can be used to formulate simulation models and optimize processing parameters for harvest,packaging,and storage.In this study,a detection platform was designed for conducting mechanical tests on different specimens at the tissue level.The system provided controllable and precise displacements;the relative error was less than±1.0%.The displacement and force measurements were calibrated.Micromechanical tests of apple parenchyma tissues were conducted to evaluate the performance of the proposed platform.The stress-strain curves of the specimens and the micrographs of the microstructures can be obtained simultaneously during the tests.The proposed platform has the capability to test mechanical properties and obtain micro behaviors of agricultural products at the tissue level,which helps in studying the failure mechanism of agricultural products under external loading.
基金support provided by the Natural Sciences and Engineering Research Council of Canada (NSERC) under the project Reducing Environmental Pollution from Veterinary Antibiotics, Endocrine Disruptive Chemicals, and Pathogens in Livestock Manurethe Department of Bioresource Engineering, McGill University for providing a Liliane and David Stewart Fellowship in Water Resources for support of this research work
文摘Most animals, including humans, produce natural sex hormones such as estrogens: 17β-estradiol(E2) and estrone(E1). These compounds are able to disrupt the reproductive systems of living organisms at trace concentrations(ng·L^(–1)). This experiment tests the hypothesis that 1% slow pyrolysis biochar-amended sandy soil could retain significant amount of estrogens(E1, E2)from poultry manure in its second year of application. The experiment was conducted over 46 days and consisted of a series of lysimeters containing sandy soil with biocharamended topsoil. The application rate of poultry manure was kept at 2.47 kg·m^(–2). The biochar held a significant concentration of hormone during the first year of its application. However, in the following year(current study), there was no significant retention of hormones in the biochar-amended soil. During the first year after application, the biochar was fresh, so its pores were available for hydrophobic interactions and held significant concentration of hormones. As time passed there were several biotic and abiotic changes on the surface of the biochar so that after some physical fragmentation, pores on the surface were no longer available for hydrophobic interactions. The biochar started releasing dissolved organic carbon, which facilitated greater mobility of hormones from poultry manure down the soil profile.
