[Objectives]To identify the authenticity of Longgu from the microscopic,infrared spectrum and chemical composition,and provide references for the quality control and evaluation methods of Longgu.[Methods]According to ...[Objectives]To identify the authenticity of Longgu from the microscopic,infrared spectrum and chemical composition,and provide references for the quality control and evaluation methods of Longgu.[Methods]According to the mineral characteristics of Longgu,the identification research was carried out by microscope observation,near-infrared spectroscopy and X-ray fluorescence spectrometer.By comparing the single polarizing and orthogonal polarizing characteristics of genuine and fake Longgu,a qualitative identification model of genuine Longgu was established based on the near-infrared spectrum of genuine Longgu,and the detection results of elements in Longgu were analyzed.[Results]The genuine Longgu had apatite optical properties,and was quite different from the fake Longgu of animal bones.Compared with modern animal bones,genuine Longgus had relatively less P and Ca,but they were enriched in elements Sr and F.The correlation coefficient model with good predictive ability can be established by using the near-infrared characteristic spectrum.[Conclusions]Polarizing microscope,near-infrared spectroscopy and X-ray fluorescence spectroscopy can improve the identification results of Longgu.展开更多
Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewa...Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewable,and clinical demand is increasingly difficult to meet,leading to a proliferation of counterfeit products.During prolonged geological burial,static pressure from the surrounding strata severely compromises the microstructural integrity of osteons in Os Draconis,but Os Draconis still largely retains the structural features of mammalian bone.Methods:Using verified authentic Os Draconis samples over 10,000 years old as a baseline,this study summarizes the ultrastructural characteristics of genuine Os Draconis.Employing electron probe microanalysis and optical polarized light microscopy,we examined 28 batches of authentic Os Draconis and 31 batches of counterfeits to identify their ultrastructural differences.Key points for ultrastructural identification of Os Draconis were compiled,and a new identification approach was proposed based on these differences.Results:Authentic Os Draconis exhibited distinct ultrastructural markers:irregularly shaped osteons with traversing fissures,deformed/displaced Haversian canals,and secondary mineral infill(predominantly calcium carbonate).Counterfeits showed regular osteon arrangements,absent traversal fissures,and homogeneous hydroxyapatite composition.Lab-simulated samples lacked structural degradation features.EPMA confirmed calcium carbonate infill in fossilized Haversian canals,while elemental profiles differentiated lacunae types(void vs.mineral-packed).Conclusion:The study established ultrastructural criteria for authentic Os Draconis identification:osteon deformation,geological fissures penetrating bone units,and heterogenous mineral deposition.These features,unattainable in counterfeits or modern processed bones,provide a cost-effective,accurate identification method.This approach bridges gaps in TCM material standardization and supports quality control for clinical applications.展开更多
2D needle-punched fiber felt was infiltrated by a kind of rapid isothermal chemical vapor infiltration technique. The infiltration process and texture transition of the infiltrated C/C composites were investigated. Th...2D needle-punched fiber felt was infiltrated by a kind of rapid isothermal chemical vapor infiltration technique. The infiltration process and texture transition of the infiltrated C/C composites were investigated. The porosity and the variations of the cumulative pore volume were determined by mercury porosimetry. The texture of matrix carbon was studied under a polarized light microscope. The results show that the relative mass gain of the sample increases directly as the infiltration time at the initial stage until 20 h, and subsequently the increasing rate of the relative mass gain decreases gradually with the prolonging of infiltration time. Three layers of pyrocarbon were formed around fibers. Low-textured pyrocarbon was obtained at the initial stage. With the densification going on, high-textured pyrocarbon was formed on the surface of low-textured pyrocarbon. Then, low-textured pyrocarbon was produced again during the final stage of densification. The texture transition is ascribed to the variation of the ratio of cumulative inner surface area to volume of pores and the gas partial pressure in pores.展开更多
Aiming at the limitation of control accuracy caused by hysteresis and creep for a piezoelectric actuator, the hysteresis phenomenon is explained based on the microscopic polarization mechanism and domain wall theory. ...Aiming at the limitation of control accuracy caused by hysteresis and creep for a piezoelectric actuator, the hysteresis phenomenon is explained based on the microscopic polarization mechanism and domain wall theory. Then a control model based on polarization is established, which can reduce the hysteresis and creep remarkablely. The experimental results show that the polarization control method is with more linearity and less hysteresis compared with the voltage control method.展开更多
As for CaZrO_(3)(CZ)ceramic,the reported dielectric property values,especially dielectric constants,were much different from 23 to 32,which is reliable and credible?Without precise property data,CZ can’t be further d...As for CaZrO_(3)(CZ)ceramic,the reported dielectric property values,especially dielectric constants,were much different from 23 to 32,which is reliable and credible?Without precise property data,CZ can’t be further developed and utilized accurately.Herein,CZ ceramic was fabricated by a traditional two-step sintering process,then simulated and calculated the dielectric properties precisely at a microscopic polarization angle using the lattice vibrational spectra and the Clausius-Mossotti(C-M)as well as damping equations.The Raman and Fourier transform far-infrared modes were analyzed and used to predict the intrinsic properties,which were consistent well with the values calculated from C-M and damping equations.The intrinsic permittivity,after precise prediction,is about 20,which is reliable and credible.As for the dielectric loss,the value of about 6×10^(-4)was obtained after precise calculation,which is similar to other results.展开更多
Differential capacitance is derived based upon energy,charge or current considerations,and determined when it may go negative or positive.These alternative views of differential capacitances are analyzed,and the relat...Differential capacitance is derived based upon energy,charge or current considerations,and determined when it may go negative or positive.These alternative views of differential capacitances are analyzed,and the relationships between them are shown.Because of recent interest in obtaining negative capacitance for reducing the subthreshold voltage swing in field effect type of devices,using ferroelectric materials characterized by permittivity,these concepts are now of paramount interest to the research community.For completeness,differential capacitance is related to the static capacitance,and conditions when the differential capacitance may go negative in relation to the static capacitance are shown.展开更多
基金Supported by the Subject Talent Research Promotion Program for"Xinglin Scholars"of Chengdu University of Traditional Chinese Medicine(ZRQN2020019).
文摘[Objectives]To identify the authenticity of Longgu from the microscopic,infrared spectrum and chemical composition,and provide references for the quality control and evaluation methods of Longgu.[Methods]According to the mineral characteristics of Longgu,the identification research was carried out by microscope observation,near-infrared spectroscopy and X-ray fluorescence spectrometer.By comparing the single polarizing and orthogonal polarizing characteristics of genuine and fake Longgu,a qualitative identification model of genuine Longgu was established based on the near-infrared spectrum of genuine Longgu,and the detection results of elements in Longgu were analyzed.[Results]The genuine Longgu had apatite optical properties,and was quite different from the fake Longgu of animal bones.Compared with modern animal bones,genuine Longgus had relatively less P and Ca,but they were enriched in elements Sr and F.The correlation coefficient model with good predictive ability can be established by using the near-infrared characteristic spectrum.[Conclusions]Polarizing microscope,near-infrared spectroscopy and X-ray fluorescence spectroscopy can improve the identification results of Longgu.
基金supported by the Scientific and Technological Innovation Project of the China Academy of Chinese Medical Sciences(CI2021A04013)the National Natural Science Foundation of China(82204610)+1 种基金the Qihang Talent Program(L2022046)the Fundamental Research Funds for the Central Public Welfare Research Institutes(ZZ15-YQ-041 and L2021029).
文摘Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewable,and clinical demand is increasingly difficult to meet,leading to a proliferation of counterfeit products.During prolonged geological burial,static pressure from the surrounding strata severely compromises the microstructural integrity of osteons in Os Draconis,but Os Draconis still largely retains the structural features of mammalian bone.Methods:Using verified authentic Os Draconis samples over 10,000 years old as a baseline,this study summarizes the ultrastructural characteristics of genuine Os Draconis.Employing electron probe microanalysis and optical polarized light microscopy,we examined 28 batches of authentic Os Draconis and 31 batches of counterfeits to identify their ultrastructural differences.Key points for ultrastructural identification of Os Draconis were compiled,and a new identification approach was proposed based on these differences.Results:Authentic Os Draconis exhibited distinct ultrastructural markers:irregularly shaped osteons with traversing fissures,deformed/displaced Haversian canals,and secondary mineral infill(predominantly calcium carbonate).Counterfeits showed regular osteon arrangements,absent traversal fissures,and homogeneous hydroxyapatite composition.Lab-simulated samples lacked structural degradation features.EPMA confirmed calcium carbonate infill in fossilized Haversian canals,while elemental profiles differentiated lacunae types(void vs.mineral-packed).Conclusion:The study established ultrastructural criteria for authentic Os Draconis identification:osteon deformation,geological fissures penetrating bone units,and heterogenous mineral deposition.These features,unattainable in counterfeits or modern processed bones,provide a cost-effective,accurate identification method.This approach bridges gaps in TCM material standardization and supports quality control for clinical applications.
基金supported by the National Natural Sci-ence Foundation of China (No. 50372050)the Foundation of Distinguished Young Scholars (No. 50225210)
文摘2D needle-punched fiber felt was infiltrated by a kind of rapid isothermal chemical vapor infiltration technique. The infiltration process and texture transition of the infiltrated C/C composites were investigated. The porosity and the variations of the cumulative pore volume were determined by mercury porosimetry. The texture of matrix carbon was studied under a polarized light microscope. The results show that the relative mass gain of the sample increases directly as the infiltration time at the initial stage until 20 h, and subsequently the increasing rate of the relative mass gain decreases gradually with the prolonging of infiltration time. Three layers of pyrocarbon were formed around fibers. Low-textured pyrocarbon was obtained at the initial stage. With the densification going on, high-textured pyrocarbon was formed on the surface of low-textured pyrocarbon. Then, low-textured pyrocarbon was produced again during the final stage of densification. The texture transition is ascribed to the variation of the ratio of cumulative inner surface area to volume of pores and the gas partial pressure in pores.
基金the National Natural Science Foundation of China (Grant No.60604031)
文摘Aiming at the limitation of control accuracy caused by hysteresis and creep for a piezoelectric actuator, the hysteresis phenomenon is explained based on the microscopic polarization mechanism and domain wall theory. Then a control model based on polarization is established, which can reduce the hysteresis and creep remarkablely. The experimental results show that the polarization control method is with more linearity and less hysteresis compared with the voltage control method.
基金the National Natural Science Foundation of China(51641206)Scientific Research Foundation of Shandong University of Science and Technology for Recruited Talents(Grant No.2016RCJJ002)the Opening Project of State Key Laboratory of High Performance Ceramics and Superfine Microstructure(Grant No.SKL201503SIC).
文摘As for CaZrO_(3)(CZ)ceramic,the reported dielectric property values,especially dielectric constants,were much different from 23 to 32,which is reliable and credible?Without precise property data,CZ can’t be further developed and utilized accurately.Herein,CZ ceramic was fabricated by a traditional two-step sintering process,then simulated and calculated the dielectric properties precisely at a microscopic polarization angle using the lattice vibrational spectra and the Clausius-Mossotti(C-M)as well as damping equations.The Raman and Fourier transform far-infrared modes were analyzed and used to predict the intrinsic properties,which were consistent well with the values calculated from C-M and damping equations.The intrinsic permittivity,after precise prediction,is about 20,which is reliable and credible.As for the dielectric loss,the value of about 6×10^(-4)was obtained after precise calculation,which is similar to other results.
文摘Differential capacitance is derived based upon energy,charge or current considerations,and determined when it may go negative or positive.These alternative views of differential capacitances are analyzed,and the relationships between them are shown.Because of recent interest in obtaining negative capacitance for reducing the subthreshold voltage swing in field effect type of devices,using ferroelectric materials characterized by permittivity,these concepts are now of paramount interest to the research community.For completeness,differential capacitance is related to the static capacitance,and conditions when the differential capacitance may go negative in relation to the static capacitance are shown.
