The nanomechanical behaviors of （110） and （111 ） CdZnTe crystals were investigated by nanoindentation. It was found that the indenter tip was adhered by the removed materials in scanning testing area although the ...The nanomechanical behaviors of （110） and （111 ） CdZnTe crystals were investigated by nanoindentation. It was found that the indenter tip was adhered by the removed materials in scanning testing area although the scanning force on the tested surface was very small （1000 nN）, which would affect the testing result of nanoindentation, so the indenter was clean before nanoindentation test. The experimemtal results showed that the hardness and Young＇s modulus decreased with the increase of indentation loads on the same plane. Because of the anisotropy of the CdZnTe crystal, the average hardness of （110） plane is 35% lower than that of （111） plane, and there are about 30% difference of the hardness along different crystallographic directions on the same plane. The hardness in 0° and 120° testing directions was the same due to the threefold symmetry of a Berkovich indenter. And the anisotropy affected the surface quality during machining of CdZnTe crystal.展开更多
Better understanding of variations in the mechanical properties of cancer cells could help to provide novel solutions for the diagnosis,prevention,and treatment of cancers.We therefore developed a calculation model of...Better understanding of variations in the mechanical properties of cancer cells could help to provide novel solutions for the diagnosis,prevention,and treatment of cancers.We therefore developed a calculation model of the intracellular elastic modulus based on the contact pressure between the silicon tip of an atomic force microscope and the target cells,and cutting depth.Ovarian cells(UACC-1598) and colon cancer cells(NCI-H716) were cut into sequential layers using an atomic force microscope silicon tip.The cutting area on the cells was 8μm×8μm,and the loading force acting on the cells was increased from 17.523 to 32.126μN.The elastic modulus distribution was measured after each cutting process.There were significant differences in contact pressure and cutting depth between different cells under the same loading force,which could be attributed to differences in their intrinsic structures and mechanical properties.The differences between the average elastic modulus and surface elastic modulus for UACC-1598 and NCI-H716 cells were 0.288±0.08 kPa and 0.376±0.16 kPa,respectively.These results demonstrate that this micro-cutting method can be used to measure intracellular mechanical properties,which could in turn provide a more accurate experimental basis for the development of novel methods for the diagnosis and treatment of various diseases.展开更多
基金supported by the Key Project of National Natural Science Foundation of China (No.50535020)
文摘The nanomechanical behaviors of （110） and （111 ） CdZnTe crystals were investigated by nanoindentation. It was found that the indenter tip was adhered by the removed materials in scanning testing area although the scanning force on the tested surface was very small （1000 nN）, which would affect the testing result of nanoindentation, so the indenter was clean before nanoindentation test. The experimemtal results showed that the hardness and Young＇s modulus decreased with the increase of indentation loads on the same plane. Because of the anisotropy of the CdZnTe crystal, the average hardness of （110） plane is 35% lower than that of （111） plane, and there are about 30% difference of the hardness along different crystallographic directions on the same plane. The hardness in 0° and 120° testing directions was the same due to the threefold symmetry of a Berkovich indenter. And the anisotropy affected the surface quality during machining of CdZnTe crystal.
基金supported by the National Natural Science Foundation of China (51175124)the Self-Planned Task of State Key Laboratory of Robotics and System of Harbin Institute of Technology (SKLRS 200903C)
文摘Better understanding of variations in the mechanical properties of cancer cells could help to provide novel solutions for the diagnosis,prevention,and treatment of cancers.We therefore developed a calculation model of the intracellular elastic modulus based on the contact pressure between the silicon tip of an atomic force microscope and the target cells,and cutting depth.Ovarian cells(UACC-1598) and colon cancer cells(NCI-H716) were cut into sequential layers using an atomic force microscope silicon tip.The cutting area on the cells was 8μm×8μm,and the loading force acting on the cells was increased from 17.523 to 32.126μN.The elastic modulus distribution was measured after each cutting process.There were significant differences in contact pressure and cutting depth between different cells under the same loading force,which could be attributed to differences in their intrinsic structures and mechanical properties.The differences between the average elastic modulus and surface elastic modulus for UACC-1598 and NCI-H716 cells were 0.288±0.08 kPa and 0.376±0.16 kPa,respectively.These results demonstrate that this micro-cutting method can be used to measure intracellular mechanical properties,which could in turn provide a more accurate experimental basis for the development of novel methods for the diagnosis and treatment of various diseases.
