基于有限元辅助测试方法(Finite element aided testing,FAT)对新型聚合物PA66开展了直至破坏的全程单轴本构关系的研究。另外,将VIC-3D光测所得的试样表面应变场结果与有限元模拟结果进行对比,表明通过FAT方法获得的聚合物PA66全程单...基于有限元辅助测试方法(Finite element aided testing,FAT)对新型聚合物PA66开展了直至破坏的全程单轴本构关系的研究。另外,将VIC-3D光测所得的试样表面应变场结果与有限元模拟结果进行对比,表明通过FAT方法获得的聚合物PA66全程单轴本构关系结果准确有效。最后给出了聚合物PA66的全程单轴本构关系曲线,给出了对应Chaboche本构关系模型的参数、材料临界破断应力、破断应变、应力三轴度等,并对试样的破断机理进行了分析。展开更多
The Zn1-xMgxO thin films were deposited on sapphire substrates by reactive electron beam evaporation deposition （REBED）. The X-ray diffraction （XRD） measurement demonstrates that these films undergo phase transiti...The Zn1-xMgxO thin films were deposited on sapphire substrates by reactive electron beam evaporation deposition （REBED）. The X-ray diffraction （XRD） measurement demonstrates that these films undergo phase transition from hexagonal to cubic with increasing the Mg concentration. Absorption coefficients at 532 nm of the samples were obtained from the absorption spectra. Using optical Kerr effect, the thirdorder susceptibilities of the ternary films over a wide range of Mg concentrations were determined. The magnitude of X^（3） of the ternary Zn1-xMgxO films is order of 10^-11 esu at λ = 532 nm. The sample with phase mixture of both hexagonal and cubic structures shows the largest third-order susceptibility. The difference observed in the magnitude of X^（3） of Zn1-xMgxO films is attributed to the different microstructures of the ternary films, such as crystalline phase separation and crystal grains that enhance stimulated scattering.展开更多
A new mixed alkali hydro-isocyanurate,RbNa(HC_(3)N_(3)O_(3))·2H_(2)O,with the noncentrosymmetric space group Pna21(No.33),has been successfully grown by a hydrothermal method.The structure can be described as 2D ...A new mixed alkali hydro-isocyanurate,RbNa(HC_(3)N_(3)O_(3))·2H_(2)O,with the noncentrosymmetric space group Pna21(No.33),has been successfully grown by a hydrothermal method.The structure can be described as 2D wavy[Na(HC_(3)N_(3)O_(3))O_(4)]∞layers separated by Rb atoms.The UV-vis diffuse reflection measurement revealed that RbNa(HC_(3)N_(3)O_(3))·2H_(2)O has a large band gap of 5.10 eV,corresponding to the UV cutoff edge of 241 nm.The polarizing microscope measurement of a micron-sized single crystal shows that RbNa(HC_(3)N_(3)O_(3))·2H_(2)O has a large birefringence of 0.194.The powder SHG measurement indicated that RbNa(HC_(3)N_(3)O_(3))·2H_(2)O exhibits a strong SHG effect that is 5.3 times that of KH_(2)PO_(4)(KDP)and can realize phase-matching in the visible and UV region.Moreover,the differences in the SHG responses between RbNa(HC_(3)N_(3)O_(3))·2H_(2)O and two isostructural compounds have been investigated,which depend heavily on the structural modulation of the(HC_(3)N_(3)O_(3))2-group by cations.Meanwhile,the electronic structures and optical properties were well analyzed using DFT methods.展开更多
The performance of infrared(IR)nonlinear optical(NLO)materials is significantly affected by the thermal conductivity kL,but studies on the structure and property relationship of kL in these materials are very rare.In ...The performance of infrared(IR)nonlinear optical(NLO)materials is significantly affected by the thermal conductivity kL,but studies on the structure and property relationship of kL in these materials are very rare.In this work we evaluated the k_(L) in IR NLO multicomponent chalcogenides Li_(x)Ag_(1-x)Ga_(y)In_(1-y)Se_(2) with a smooth change in the compositions x and y by using a machine learning approach and laser flash measurements,combined with available experimental results.The found patterns of kL dependence on the atomic mass,bond length and electronegativity provide an effective understanding for navigation in the process of searching for new chalcogenide crystals with an optimal set of parameters that allow them to be effectively used as a frequency converter of laser radiation in the IR range.Moreover,the compositions Li_(0.5)Ag_(0.5)GaSe_(2),Li_(0.81)Ag_(0.19)InSe_(2) and AgGa_(0.5)In_(0.5)Se_(2) are demonstrated to exhibit a balanced combination of the parameters kL,NLOeffects,energy band gaps,and birefringence for IR NLO applications.展开更多
基金The National Natural Science Foundation of China(90922035)the Knowledge Innovation Program of the Chinese Academy of Sciences(KJCX2-EW-H03)Fujian High Technology Research and Development Program(2012H0046)
文摘基于有限元辅助测试方法(Finite element aided testing,FAT)对新型聚合物PA66开展了直至破坏的全程单轴本构关系的研究。另外,将VIC-3D光测所得的试样表面应变场结果与有限元模拟结果进行对比,表明通过FAT方法获得的聚合物PA66全程单轴本构关系结果准确有效。最后给出了聚合物PA66的全程单轴本构关系曲线,给出了对应Chaboche本构关系模型的参数、材料临界破断应力、破断应变、应力三轴度等,并对试样的破断机理进行了分析。
基金This work was supported by the National Natural Sci-ence Foundation of China under Grant No. 10174064and 50472058.
文摘The Zn1-xMgxO thin films were deposited on sapphire substrates by reactive electron beam evaporation deposition （REBED）. The X-ray diffraction （XRD） measurement demonstrates that these films undergo phase transition from hexagonal to cubic with increasing the Mg concentration. Absorption coefficients at 532 nm of the samples were obtained from the absorption spectra. Using optical Kerr effect, the thirdorder susceptibilities of the ternary films over a wide range of Mg concentrations were determined. The magnitude of X^（3） of the ternary Zn1-xMgxO films is order of 10^-11 esu at λ = 532 nm. The sample with phase mixture of both hexagonal and cubic structures shows the largest third-order susceptibility. The difference observed in the magnitude of X^（3） of Zn1-xMgxO films is attributed to the different microstructures of the ternary films, such as crystalline phase separation and crystal grains that enhance stimulated scattering.
基金supported by the National Natural Science Foundation of China(Grant No 21975255,51890862,U1605245,and 51425205)the National Key Research and Development Plan of Ministry of Science and Technology(Grant No 2016YFB0402104)+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No XDB20000000)the NSF of Fujian Province(2019J01020758)the Youth Innovation Promotion Association CAS(303).
文摘A new mixed alkali hydro-isocyanurate,RbNa(HC_(3)N_(3)O_(3))·2H_(2)O,with the noncentrosymmetric space group Pna21(No.33),has been successfully grown by a hydrothermal method.The structure can be described as 2D wavy[Na(HC_(3)N_(3)O_(3))O_(4)]∞layers separated by Rb atoms.The UV-vis diffuse reflection measurement revealed that RbNa(HC_(3)N_(3)O_(3))·2H_(2)O has a large band gap of 5.10 eV,corresponding to the UV cutoff edge of 241 nm.The polarizing microscope measurement of a micron-sized single crystal shows that RbNa(HC_(3)N_(3)O_(3))·2H_(2)O has a large birefringence of 0.194.The powder SHG measurement indicated that RbNa(HC_(3)N_(3)O_(3))·2H_(2)O exhibits a strong SHG effect that is 5.3 times that of KH_(2)PO_(4)(KDP)and can realize phase-matching in the visible and UV region.Moreover,the differences in the SHG responses between RbNa(HC_(3)N_(3)O_(3))·2H_(2)O and two isostructural compounds have been investigated,which depend heavily on the structural modulation of the(HC_(3)N_(3)O_(3))2-group by cations.Meanwhile,the electronic structures and optical properties were well analyzed using DFT methods.
基金supported by the National Natural Science Foundation of China(Grant No.22133004)the Ministry of Education and Science of the Russian Federation,Grant FSUS-2025-0011(crystal structure analysis)partly by the state assignment of IGM SB RAS No.122041400031-2(crystal growth).
文摘The performance of infrared(IR)nonlinear optical(NLO)materials is significantly affected by the thermal conductivity kL,but studies on the structure and property relationship of kL in these materials are very rare.In this work we evaluated the k_(L) in IR NLO multicomponent chalcogenides Li_(x)Ag_(1-x)Ga_(y)In_(1-y)Se_(2) with a smooth change in the compositions x and y by using a machine learning approach and laser flash measurements,combined with available experimental results.The found patterns of kL dependence on the atomic mass,bond length and electronegativity provide an effective understanding for navigation in the process of searching for new chalcogenide crystals with an optimal set of parameters that allow them to be effectively used as a frequency converter of laser radiation in the IR range.Moreover,the compositions Li_(0.5)Ag_(0.5)GaSe_(2),Li_(0.81)Ag_(0.19)InSe_(2) and AgGa_(0.5)In_(0.5)Se_(2) are demonstrated to exhibit a balanced combination of the parameters kL,NLOeffects,energy band gaps,and birefringence for IR NLO applications.
