To address the issues of short setting time and high bleeding rate of A component,which easily cause pipe plugging and poor grouting performance when a two-component grout is injected synchronously behind the Segmenta...To address the issues of short setting time and high bleeding rate of A component,which easily cause pipe plugging and poor grouting performance when a two-component grout is injected synchronously behind the Segmental Lining,the inorganic retarder sodium pyrophosphate(TSPP)and three organic retarders were added to the A component:sodium citrate(SC),sodium tartrate(ST)and glycerol(GLY).The effect law and microscopic mechanism of viscosity,bleeding rate,setting time,gelling time,compressive strength,and stone rate were investigated.The results revealed that the addition of retarders could enhance the stability and setting time of the A component and increase the gelling time,stone rate,and compressive strength of two-component grout.Among them,the performance of the grout with an SC dosage of 0.1% was superior.The bleeding rate of this grout was reduced to 3.5%,the stone rate of the two-component grout was more than 99%,and the early compressive strength and late compressive strength of this grout were increased by approximately 35% and 7%,respectively.The initial and final setting time of the A component with a TSPP dosage of 0.3% was the longest,which was prolonged to 17 and 26 h,respectively.Microscopic analysis revealed that the four retarders hindered the hydration process of cement through complexation and adsorption,and inhibited the hydration of C_(3)S and the crystallisation of CH.Moreover,they reduced the defects caused by the rapid reaction of water glass and CH on the solid phase structure,enabled the microstructure of the stone body to be denser,and subsequently,enhanced the compressive strength.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
Optical microscopes with polishing equipment possess high performance/cost ratio for refractories industry. Here, the preparation of polishing sections of refractory materials and products and their observation under ...Optical microscopes with polishing equipment possess high performance/cost ratio for refractories industry. Here, the preparation of polishing sections of refractory materials and products and their observation under microscopes were introduced in detail. The observation of microstructures helps to improve and optimize production process. Optical microscopes can observe （1） homogenous or inhomogeneous composition distribution to improve mixing intensity; （2） coarse grains contact or not and contacted grain edges broken or intact to adjust the pressing parameters to avoid overpressure ; （ 3 ） the filling degree of components to optimize the particle size distribution; （4） the sintering necks and bridges and matrix shrinkage status to adjust sintering intensity or sintering atmosphere; （5） the crack edge in round or sharp to know when the cracks formed （ before or after entering sintering zone） and take countermeasures ; （6） used refractories to find the wear mechanism.展开更多
A novel constant force feedback mechanism based on fuzzy logic for tapping mode Atomic Force Microscopes (AFM) is proposed in this paper. A mathematical model for characterizing the cantilever-sample interaction subsy...A novel constant force feedback mechanism based on fuzzy logic for tapping mode Atomic Force Microscopes (AFM) is proposed in this paper. A mathematical model for characterizing the cantilever-sample interaction subsystem which is nonlinear and contains large uncertainty is first developed. Then, a PID-like fuzzy controller, combing a PD-like fuzzy controller and a PI controller, is designed to regulate the controller efforts and schedule the applied voltage of the Z-axis of the piezoelectric tube scanner to maintain a constant tip-sample interaction force during sample-scanning. Using the PID-like fuzzy controller allows the cantilever tip to track sample surface rapidly and accurately even though the topography of the surface is arbitrary and not given in advance. This rapid tracking response facilitates us to observe samples with high aspect ratio micro structures accurately and quickly. Besides, the overshoot which will result in tip crash in commercial AFMs with a traditional PID controller could be avoided. Additionally, the controller efforts can be intelligently scheduled by using the fuzzy logic. Thus, continuous manual gain-tuning by trial and error such as those in commercial AFMs is alleviated. In final, computer simulations and experimental verifications are provided to demonstrate the effectiveness and confirm the validity of the proposed controller.展开更多
以硅橡胶为基体,添加无机填料制备的耐热涂层在耐热防腐方面有重要应用前景。采用自制改性硅橡胶作基体,添加不同配比的高岭土、二氧化硅和氧化铝,制备了复合涂层。采用扫描电子显微镜(scanning electron microscopy,SEM)观察了硅橡胶...以硅橡胶为基体,添加无机填料制备的耐热涂层在耐热防腐方面有重要应用前景。采用自制改性硅橡胶作基体,添加不同配比的高岭土、二氧化硅和氧化铝,制备了复合涂层。采用扫描电子显微镜(scanning electron microscopy,SEM)观察了硅橡胶基体中无机填料的分散状况,采用热重分析仪(thermogravimetric analyzer,TGA)对复合涂层的热解温度和失重率进行了分析。结果表明:在复合体系中,无机填料与基体的相容性较好,分散均匀;与基体材料相比,无机填料的添加可有效提高复合材料的耐热性。填料质量分数为20%的复合涂层,其在800℃时质量残留率比自制改性硅橡胶的基体提高了10%以上。展开更多
Microscopes in vacuum ultraviolet and soft X-ray regions using a normal incidence type of Schwarzschild objective are reviewed. The objective consists of a concave mirror and a convex mirror coated with a high reflect...Microscopes in vacuum ultraviolet and soft X-ray regions using a normal incidence type of Schwarzschild objective are reviewed. The objective consists of a concave mirror and a convex mirror coated with a high reflectance multilayer,having a large numerical aperture comparing with other objectives. The microscopes have been used to diagnose inertia-confinement-fusion plasmas,and to investigate small samples or microstructures of in- organic and organic materials by imaging them using laboratory light sources. Synchrotron radiation has been also used to obtain a microbeam for a photoelectron scanning microscope with a spatial resolution of 0.1 μm. The struc- ture and performance of two laboratory microscopes developed at Tohoku University are demonstrated. One of them is a soft X-ray emission imaging microscope. An image of an artificial pattern made of W and SiO2 on Si wafer by focusing Si L emission was presented. The other is an ultraviolet photoelectron scanning microscope using a He (he- lium) gas discharge lamp. The valence band spectra of a microcrystal of FeWO4 were presented. Furthermore other applications such as demagnifying optics for lithography and optics to gather fluorescence for emission spectroscopy are introduced.展开更多
基金Funded by the National Natural Science Foundation of China(No.52378394)the Fundamental Research Funds for the Central Universities(No.B230201037)。
文摘To address the issues of short setting time and high bleeding rate of A component,which easily cause pipe plugging and poor grouting performance when a two-component grout is injected synchronously behind the Segmental Lining,the inorganic retarder sodium pyrophosphate(TSPP)and three organic retarders were added to the A component:sodium citrate(SC),sodium tartrate(ST)and glycerol(GLY).The effect law and microscopic mechanism of viscosity,bleeding rate,setting time,gelling time,compressive strength,and stone rate were investigated.The results revealed that the addition of retarders could enhance the stability and setting time of the A component and increase the gelling time,stone rate,and compressive strength of two-component grout.Among them,the performance of the grout with an SC dosage of 0.1% was superior.The bleeding rate of this grout was reduced to 3.5%,the stone rate of the two-component grout was more than 99%,and the early compressive strength and late compressive strength of this grout were increased by approximately 35% and 7%,respectively.The initial and final setting time of the A component with a TSPP dosage of 0.3% was the longest,which was prolonged to 17 and 26 h,respectively.Microscopic analysis revealed that the four retarders hindered the hydration process of cement through complexation and adsorption,and inhibited the hydration of C_(3)S and the crystallisation of CH.Moreover,they reduced the defects caused by the rapid reaction of water glass and CH on the solid phase structure,enabled the microstructure of the stone body to be denser,and subsequently,enhanced the compressive strength.
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.
文摘Optical microscopes with polishing equipment possess high performance/cost ratio for refractories industry. Here, the preparation of polishing sections of refractory materials and products and their observation under microscopes were introduced in detail. The observation of microstructures helps to improve and optimize production process. Optical microscopes can observe （1） homogenous or inhomogeneous composition distribution to improve mixing intensity; （2） coarse grains contact or not and contacted grain edges broken or intact to adjust the pressing parameters to avoid overpressure ; （ 3 ） the filling degree of components to optimize the particle size distribution; （4） the sintering necks and bridges and matrix shrinkage status to adjust sintering intensity or sintering atmosphere; （5） the crack edge in round or sharp to know when the cracks formed （ before or after entering sintering zone） and take countermeasures ; （6） used refractories to find the wear mechanism.
文摘A novel constant force feedback mechanism based on fuzzy logic for tapping mode Atomic Force Microscopes (AFM) is proposed in this paper. A mathematical model for characterizing the cantilever-sample interaction subsystem which is nonlinear and contains large uncertainty is first developed. Then, a PID-like fuzzy controller, combing a PD-like fuzzy controller and a PI controller, is designed to regulate the controller efforts and schedule the applied voltage of the Z-axis of the piezoelectric tube scanner to maintain a constant tip-sample interaction force during sample-scanning. Using the PID-like fuzzy controller allows the cantilever tip to track sample surface rapidly and accurately even though the topography of the surface is arbitrary and not given in advance. This rapid tracking response facilitates us to observe samples with high aspect ratio micro structures accurately and quickly. Besides, the overshoot which will result in tip crash in commercial AFMs with a traditional PID controller could be avoided. Additionally, the controller efforts can be intelligently scheduled by using the fuzzy logic. Thus, continuous manual gain-tuning by trial and error such as those in commercial AFMs is alleviated. In final, computer simulations and experimental verifications are provided to demonstrate the effectiveness and confirm the validity of the proposed controller.
文摘以硅橡胶为基体,添加无机填料制备的耐热涂层在耐热防腐方面有重要应用前景。采用自制改性硅橡胶作基体,添加不同配比的高岭土、二氧化硅和氧化铝,制备了复合涂层。采用扫描电子显微镜(scanning electron microscopy,SEM)观察了硅橡胶基体中无机填料的分散状况,采用热重分析仪(thermogravimetric analyzer,TGA)对复合涂层的热解温度和失重率进行了分析。结果表明:在复合体系中,无机填料与基体的相容性较好,分散均匀;与基体材料相比,无机填料的添加可有效提高复合材料的耐热性。填料质量分数为20%的复合涂层,其在800℃时质量残留率比自制改性硅橡胶的基体提高了10%以上。
文摘Microscopes in vacuum ultraviolet and soft X-ray regions using a normal incidence type of Schwarzschild objective are reviewed. The objective consists of a concave mirror and a convex mirror coated with a high reflectance multilayer,having a large numerical aperture comparing with other objectives. The microscopes have been used to diagnose inertia-confinement-fusion plasmas,and to investigate small samples or microstructures of in- organic and organic materials by imaging them using laboratory light sources. Synchrotron radiation has been also used to obtain a microbeam for a photoelectron scanning microscope with a spatial resolution of 0.1 μm. The struc- ture and performance of two laboratory microscopes developed at Tohoku University are demonstrated. One of them is a soft X-ray emission imaging microscope. An image of an artificial pattern made of W and SiO2 on Si wafer by focusing Si L emission was presented. The other is an ultraviolet photoelectron scanning microscope using a He (he- lium) gas discharge lamp. The valence band spectra of a microcrystal of FeWO4 were presented. Furthermore other applications such as demagnifying optics for lithography and optics to gather fluorescence for emission spectroscopy are introduced.
