Using a rigorous mathematical approach, we demonstrate how the Cosmic Microwave Background (CMB) temperature could simply be a form of geometric mean temperature between the minimum time-dependent Hawking Hubble tempe...Using a rigorous mathematical approach, we demonstrate how the Cosmic Microwave Background (CMB) temperature could simply be a form of geometric mean temperature between the minimum time-dependent Hawking Hubble temperature and the maximum Planck temperature of the expanding universe over the course of cosmic time. This mathematical discovery suggests a re-consideration of Rh=ctcosmological models, including black hole cosmological models, even if it possibly could also be consistent with the Λ-CDM model. Most importantly, this paper contributes to the growing literature in the past year asserting a tightly constrained mathematical relationship between the CMB temperature, the Hubble constant, and other global parameters of the Hubble sphere. Our approach suggests a solid theoretical framework for predicting and understanding the CMB temperature rather than solely observing it.1.展开更多
目的为评价CEREC椅旁CAD/CAM系统制作的IPS e.max CAD玻璃陶瓷高嵌体应用于根管治疗后牙缺损病例的临床效果。方法选择42例根管治疗后牙,应用高嵌体的牙体预备方式,采用CEREC椅旁CAD/CAM修复系统和IPS e.max CAD玻璃陶瓷,即刻完成修复...目的为评价CEREC椅旁CAD/CAM系统制作的IPS e.max CAD玻璃陶瓷高嵌体应用于根管治疗后牙缺损病例的临床效果。方法选择42例根管治疗后牙,应用高嵌体的牙体预备方式,采用CEREC椅旁CAD/CAM修复系统和IPS e.max CAD玻璃陶瓷,即刻完成修复体并粘接;修复1年后复查,参照改良修正后的美国公众健康服务标准(US Public Health Service Criteria,USPHS),在修复体边缘染色、边缘继发龋、修复体边缘适合性、修复体崩瓷折裂或脱落、修复体颜色、牙龈健康状况、修复体邻接关系、患者满意度8个方面进行评价。结果修复体边缘染色C级病例1例,成功率97.6%;边缘继发龋C级病例1例,成功率97.6%;修复体邻接关系欠佳C级病例1例,成功率97.6%;在边缘适合性、修复体崩瓷折裂或脱落、修复体颜色、牙龈健康状况、患者满意方面表现优秀,成功率均为100%。结论椅旁CAD/CAM系统制作的IPS e.maxCAD高嵌体修复体在短期内可取得良好的修复效果。展开更多
A radical attempt to develop the Planck ether theory has been made by Winterberg who, however, assumes positive and negative Planck masses in order to have a zero cosmological constant and to overcome the divergence ...A radical attempt to develop the Planck ether theory has been made by Winterberg who, however, assumes positive and negative Planck masses in order to have a zero cosmological constant and to overcome the divergence problems of quantum electrodynamics. Now, it is evident that two opposite Planckions,interact- ing with each other have parallel accelerations, thus going on accelerating each other up to infinite energy. We also show that a negative inertia leads to self-acceleration of a simple particle because of the fields present in any interaction, even those relative to ' contact' actions which are unable to produce Winterberg's vortex rings without the use of long range forces. The appearance of the electric field in the Planckion model is unjustified and in contradiction with MacCullagh's condition used by Winterberg, We suggest a possible solution. Other difficulties regard the nonannihilation of the positive and negative Planckions, although they are antiparticles to each other, and the justification of the elementary particle masses which are small submultiples of the Planck masses. Finally, Winterberg thinks of having derived special relativity from prerelativistic physics by demanding invariance of the Lorentz condition under both Galilei and Lorentz transformations, which is impossible. What is worse is that Wintorberg does not refer to the same space-time events in writing his transforma- tions. Suggestions to improve Winterberg's theory are given.展开更多
The discovery of the Planck relation is generally regarded as the starting point of quantum physics.Planck＇s constant h is now regarded as one of the most important universal constants.The physical nature of h,howeve...The discovery of the Planck relation is generally regarded as the starting point of quantum physics.Planck＇s constant h is now regarded as one of the most important universal constants.The physical nature of h,however,has not been well understood.It was originally suggested as a fitting constant to explain the black-body radiation.Although Planck had proposed a theoretical justification of h,he was never satisfied with that.To solve this outstanding problem,we use the Maxwell theory to directly calculate the energy and momentum of a radiation wave packet.We find that the energy of the wave packet is indeed proportional to its oscillation frequency.This allows us to derive the value of Planck＇s constant.Furthermore,we show that the emission and transmission of a photon follows the all-or-none principle.The ＂strength＂ of the wave packet can be characterized by ζ,which represents the integrated strength of the vector potential along a transverse axis.We reason that ζ should have a fixed cut-off value for all photons.Our results suggest that a wave packet can behave like a particle.This offers a simple explanation to the recent satellite observations that the cosmic microwave background follows closely the black-body radiation as predicted by Planck＇s law.展开更多
In this article, we establish the exponential time decay of smooth solutions around a global Maxwellian to the non-linear Vlasov–Poisson–Fokker–Planck equations in the whole space by uniform-in-time energy estimate...In this article, we establish the exponential time decay of smooth solutions around a global Maxwellian to the non-linear Vlasov–Poisson–Fokker–Planck equations in the whole space by uniform-in-time energy estimates. The non-linear coupling of macroscopic part and Fokker–Planck operator in the model brings new difficulties for the energy estimates, which is resolved by adding tailored weighted-in-v energy estimates suitable for the Fokker–Planck operator.展开更多
文摘Using a rigorous mathematical approach, we demonstrate how the Cosmic Microwave Background (CMB) temperature could simply be a form of geometric mean temperature between the minimum time-dependent Hawking Hubble temperature and the maximum Planck temperature of the expanding universe over the course of cosmic time. This mathematical discovery suggests a re-consideration of Rh=ctcosmological models, including black hole cosmological models, even if it possibly could also be consistent with the Λ-CDM model. Most importantly, this paper contributes to the growing literature in the past year asserting a tightly constrained mathematical relationship between the CMB temperature, the Hubble constant, and other global parameters of the Hubble sphere. Our approach suggests a solid theoretical framework for predicting and understanding the CMB temperature rather than solely observing it.1.
文摘目的为评价CEREC椅旁CAD/CAM系统制作的IPS e.max CAD玻璃陶瓷高嵌体应用于根管治疗后牙缺损病例的临床效果。方法选择42例根管治疗后牙,应用高嵌体的牙体预备方式,采用CEREC椅旁CAD/CAM修复系统和IPS e.max CAD玻璃陶瓷,即刻完成修复体并粘接;修复1年后复查,参照改良修正后的美国公众健康服务标准(US Public Health Service Criteria,USPHS),在修复体边缘染色、边缘继发龋、修复体边缘适合性、修复体崩瓷折裂或脱落、修复体颜色、牙龈健康状况、修复体邻接关系、患者满意度8个方面进行评价。结果修复体边缘染色C级病例1例,成功率97.6%;边缘继发龋C级病例1例,成功率97.6%;修复体邻接关系欠佳C级病例1例,成功率97.6%;在边缘适合性、修复体崩瓷折裂或脱落、修复体颜色、牙龈健康状况、患者满意方面表现优秀,成功率均为100%。结论椅旁CAD/CAM系统制作的IPS e.maxCAD高嵌体修复体在短期内可取得良好的修复效果。
文摘A radical attempt to develop the Planck ether theory has been made by Winterberg who, however, assumes positive and negative Planck masses in order to have a zero cosmological constant and to overcome the divergence problems of quantum electrodynamics. Now, it is evident that two opposite Planckions,interact- ing with each other have parallel accelerations, thus going on accelerating each other up to infinite energy. We also show that a negative inertia leads to self-acceleration of a simple particle because of the fields present in any interaction, even those relative to ' contact' actions which are unable to produce Winterberg's vortex rings without the use of long range forces. The appearance of the electric field in the Planckion model is unjustified and in contradiction with MacCullagh's condition used by Winterberg, We suggest a possible solution. Other difficulties regard the nonannihilation of the positive and negative Planckions, although they are antiparticles to each other, and the justification of the elementary particle masses which are small submultiples of the Planck masses. Finally, Winterberg thinks of having derived special relativity from prerelativistic physics by demanding invariance of the Lorentz condition under both Galilei and Lorentz transformations, which is impossible. What is worse is that Wintorberg does not refer to the same space-time events in writing his transforma- tions. Suggestions to improve Winterberg's theory are given.
基金Project partially supported by the Research Grant Council of Hong Kong,China(Grant No.RGC 660207)the Macro-Science Program,Hong Kong University of Science and Technology,China(Grant No.DCC 00/01.SC01)
文摘The discovery of the Planck relation is generally regarded as the starting point of quantum physics.Planck＇s constant h is now regarded as one of the most important universal constants.The physical nature of h,however,has not been well understood.It was originally suggested as a fitting constant to explain the black-body radiation.Although Planck had proposed a theoretical justification of h,he was never satisfied with that.To solve this outstanding problem,we use the Maxwell theory to directly calculate the energy and momentum of a radiation wave packet.We find that the energy of the wave packet is indeed proportional to its oscillation frequency.This allows us to derive the value of Planck＇s constant.Furthermore,we show that the emission and transmission of a photon follows the all-or-none principle.The ＂strength＂ of the wave packet can be characterized by ζ,which represents the integrated strength of the vector potential along a transverse axis.We reason that ζ should have a fixed cut-off value for all photons.Our results suggest that a wave packet can behave like a particle.This offers a simple explanation to the recent satellite observations that the cosmic microwave background follows closely the black-body radiation as predicted by Planck＇s law.
文摘将α-Fe_(2)O_(3)@C与钛粉和铝粉一同进行高温煅烧,制备了Fe O@C/MAX(FCM)复合材料。通过XRD、SEM、TEM表征了FCM复合材料在不同Ti/C与Al/C物质的量比下的结构、组成及形貌变化,采用电化学动力学分析方法定量计算了FCM复合材料的赝电容占比,推测可能的电荷储存机理。结果表明,随着Ti/C与Al/C物质的量比的增大,FCM复合材料中MAX相(Ti_(2)Al C和Ti_(3)Al C_(2))的含量随之变化,而α-Fe_(2)O_(3)转变为不稳定的Fe O。当n(Ti)∶n(Al)∶n(C)=3∶1∶2时,制得的FCM-312样品在1 m V/s扫描速率下的比电容最大,为125.09 F/g,约为α-Fe_(2)O_(3)@C的4.76倍。FCM复合材料中部分MAX相在电化学过程中发生氧化还原反应,为离子间电子快速输运提供了条件,增加了FCM复合材料的赝电容占比。其中,FCM-312样品在10 m V/s扫描速率下的赝电容占比为22.12%。
基金partially supported by Fundamental Research Funds for the Central Universities,NSFC(11871335)by the SJTU’s SMC Projection
文摘In this article, we establish the exponential time decay of smooth solutions around a global Maxwellian to the non-linear Vlasov–Poisson–Fokker–Planck equations in the whole space by uniform-in-time energy estimates. The non-linear coupling of macroscopic part and Fokker–Planck operator in the model brings new difficulties for the energy estimates, which is resolved by adding tailored weighted-in-v energy estimates suitable for the Fokker–Planck operator.
