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Influence of topography on the fine structures of stratospheric gravity waves:An analysis using COSMIC-2 temperature data 被引量:1
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作者 JiaRui Wei Xiao Liu +2 位作者 JiYao Xu QinZeng Li Hong Gao 《Earth and Planetary Physics》 EI CAS CSCD 2024年第3期497-513,共17页
We derive the potential energy of gravity waves(GWs)in the upper troposphere and stratosphere at 45°S-45°N from December 2019 to November 2022 by using temperature profiles retrieved from the Constellation O... We derive the potential energy of gravity waves(GWs)in the upper troposphere and stratosphere at 45°S-45°N from December 2019 to November 2022 by using temperature profiles retrieved from the Constellation Observing System for Meteorology,Ionosphere,and Climate-2(COSMIC-2)satellite.Owing to the dense sampling of COSMIC-2,in addition to the strong peaks of gravity wave potential energy(GWPE)above the Andes and Tibetan Plateau,we found weak peaks above the Rocky,Atlas,Caucasus,and Tianshan Mountains.The land-sea contrast is responsible for the longitudinal variations of the GWPE in the lower and upper stratosphere.At 40°N/S,the peaks were mainly above the topographic regions during the winter.At 20°N/S,the peaks were a slight distance away from the topographic regions and might be the combined effect of nontopographic GWs and mountain waves.Near the Equator,the peaks were mainly above the regions with the lowest sea level altitude and may have resulted from convection.Our results indicate that even above the local regions with lower sea level altitudes compared with the Andes and Tibetan Plateau,the GWPE also exhibits fine structures in geographic distributions.We found that dissipation layers above the tropopause jet provide the body force to generate secondary waves in the upper stratosphere,especially during the winter months of each hemisphere and at latitudes of greater than 20°N/S. 展开更多
关键词 TOPOGRAPHY fine structures stratospheric gravity waves Constellation Observing System for Meteorology Ionosphere and Climate-2(COSMIC-2) dissipation layers
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Structural properties of residual carbon in coal gasification fine slag and their influence on flotation separation and resource utilization:A review 被引量:6
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作者 Rui Han Anning Zhou +4 位作者 Ningning Zhang Kaiqiang Guo Mengyan Cheng Heng Chen Cuicui Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期217-230,共14页
Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery a... Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery and the high-value utilization of residual carbon(RC)in FS are the keys to realizing the win-win situation of the coal chemical industry in terms of economic and environmental benefits.The structural properties,such as pore,surface functional group,and microcrystalline structures,of RC in FS(FS-RC)not only affect the flotation recovery efficiency of FS-RC but also form the basis for the high-value utilization of FS-RC.In this paper,the characteristics of FS-RC in terms of pore structure,surface functional groups,and microcrystalline structure are sorted out in accordance with gasification type and FS particle size.The reasons for the formation of the special structural properties of FS-RC are analyzed,and their influence on the flotation separation and high-value utilization of FS-RC is summarized.Separation methods based on the pore structural characterist-ics of FS-RC,such as ultrasonic pretreatment-pore-blocking flotation and pore breaking-flocculation flotation,are proposed to be the key development technologies for improving FS-RC recovery in the future.The design of low-cost,low-dose collectors containing polar bonds based on the surface and microcrystalline structures of FS-RC is proposed to be an important breakthrough point for strengthening the flotation efficiency of FS-RC in the future.The high-value utilization of FS should be based on the physicochemical structural proper-ties of FS-RC and should focus on the environmental impact of hazardous elements and the recyclability of chemical waste liquid to es-tablish an environmentally friendly utilization method.This review is of great theoretical importance for the comprehensive understand-ing of the unique structural properties of FS-RC,the breakthrough of the technological bottleneck in the efficient flotation separation of FS,and the expansion of the field of the high value-added utilization of FS-RC. 展开更多
关键词 coal gasification fine slag residual carbon pore structure surface functional groups microcrystalline structure flotation sep-aration resource utilization
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EFFECTS OF ALLOYING ELEMENTS ON CREEP OF TiAl ALLOYS WITH FINELAMELLAR STRUCTURES 被引量:2
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作者 J.N.Wang, B.Y.Huang and T.G.Nieh  National Key Laboratory for Powder Metallurgy, Central South University of Technology, Changsha 410083, China  Lawrence Livermore National Laboratory, P.O.Box 808, Livermore, CA 94550, U.S.A. 《中国有色金属学会会刊:英文版》 CSCD 1999年第S1期263-273,共11页
Creep experiments have been conducted on five powder metallurgy TiAl alloys with fine grains (65~80 μm), fine lamellar spacings (0.1~0.16 μm), and different compositions [Ti 47Al(+Cr, Nb, Ta, W, Si)] at temperatur... Creep experiments have been conducted on five powder metallurgy TiAl alloys with fine grains (65~80 μm), fine lamellar spacings (0.1~0.16 μm), and different compositions [Ti 47Al(+Cr, Nb, Ta, W, Si)] at temperatures of 760 ℃ and 815 ℃ and stresses from 35 to 723 MPa. Results show that at a given lamellar spacing 1% Nb(mole fraction) with 1% Ta and replacing 0.2% Ta with 0.2% W induced little effect, but addition of 0.3% Si decreased the creep resistance by a factor of 3~4 under otherwise identical conditions. These different effects of different alloying elements are interpreted in terms of the interaction of alloy segregants with misfit and/or misorientaion dislocations at the lamellar interface. That is, the interaction retards or facilitates the climb of interfacial dislocations, which is rate controlling during creep, depending on the size of the segregants relative to the host atoms. 展开更多
关键词 TIAL alloys fine LAMELLAR structures CREEP ALLOYING elements
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Quick-scanning X-ray absorption fine structure beamline at SSRF
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作者 Yu Chen Qian Gao +2 位作者 Zheng Jiang Jiong Li Shuo Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第6期1-13,共13页
The layout and characteristics of the hard X-ray spectroscopy beamline(BL11B)at the Shanghai synchrotron radiation facility are described herein.BL11B is a bending-magnet beamline dedicated to conventional and millise... The layout and characteristics of the hard X-ray spectroscopy beamline(BL11B)at the Shanghai synchrotron radiation facility are described herein.BL11B is a bending-magnet beamline dedicated to conventional and millisecond-scale quick-scanning X-ray absorption fine structures.It is equipped with a cylindrical collimating mirror,a double-crystal monochromator comprising Si(111)and Si(311),a channel-cut quick-scanning Si(111)monochromator,a toroidal focusing mirror,and a high harmonics rejection mirror.It can provide 5-30 keV of X-rays with a photon flux of~5×10^(11)photons/s and an energy resolution of~1.31×10^(-4)at 10 keV.The performance of the beamline can satisfy the demands of users in the fields of catalysis,materials,and environmental science.This paper presents an overview of the beamline design and a detailed description of its performance and capabilities. 展开更多
关键词 Bending magnet beamline X-ray absorption fine structure Quick-scanning XAFS In situ Synchrotron radiation
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Possible radio precursors/signatures of the CMEs onset:radio type Ⅲ bursts and fine structures in the centimeter-metric wavelength region 被引量:2
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作者 MinWang Guan-NanGa01 +1 位作者 Rui-XiangXie Cheng-MingTan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第5期607-616,共10页
Seventy-one occurrences of coronal mass ejections (CMEs) associated with radio bursts, seemingly associated with type III bursts/fine structures (FSs), in the centimeter-metric frequency range during 2003-2005, we... Seventy-one occurrences of coronal mass ejections (CMEs) associated with radio bursts, seemingly associated with type III bursts/fine structures (FSs), in the centimeter-metric frequency range during 2003-2005, were obtained with the spectrometers at the National Astronomical Observatories, Chinese Academy of Sciences (NAOC) and the Culgoora radio spectrometer and are presented. The statistical results of 68 out of 71 events associated with the radio type III bursts or FSs during the initiation or early stages of the CMEs indicate that most CMEs contain the emissions of radio type III bursts/FSs near the time of the CME's onset, in spite of their fast or slow speeds. Therefore, we propose that type III bursts and FSs are possible precursors of the onset of CMEs. We stress that the radio type III bursts/FSs in the centimetermetric wavelength region and the CME transients possibly occurred in conjunction with the origin of the coronal precursor structures. Thus, the statistical results support the suggestions that type III bursts/FSs are indicators of extra energy input into the corona at the CMEs' onset, and that the type III bursts/FSs are produced primarily due to a coronal instability which eventually triggers the CME process. This may signify that the centimeter-metric radio bursts corresponding to or near the CME's onset are caused by the disturbed corona (possibly including minor magnetic reconnections). 展开更多
关键词 Sun: radio burst - radio fine structure -coronal mass ejection
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Effect of milling process on the core-shell structures and dielectric properties of fine-grained BaTiO_3-based X7R ceramic materials 被引量:3
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作者 Tian Wang Xiao-hui Wang Hai Wen Long-tu Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2009年第3期345-348,共4页
Fine-grained BaTiO3-based X7R ceramic materials were prepared and the effects of milling process on the core-shell structures and dielectric properties were investigated using scanning electron microscope, transmissio... Fine-grained BaTiO3-based X7R ceramic materials were prepared and the effects of milling process on the core-shell structures and dielectric properties were investigated using scanning electron microscope, transmission electron microscope, and energy dispersive spectroscopy (EDS). As the milling time extends, the dielectric constant of the ceramics increases, whereas the temperature coefficient of capacitance at 125℃ drops quickly. The changes in dielectric properties are considered relevant to the microstructure evolution caused by the milling process. Defects on the surface of BaTiO3 particles increase because of the effects of milling process, which will make it easier for additives to diffuse into the interior grains. As the milling time increases, the shell region gets thicker and the core region gets smaller; however, EDS results show that the chemical inhomogeneity between grain core and grain shell becomes weaker. 展开更多
关键词 fine-grain barium titanate core-shell structure milling process microstructure CAPACITOR
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FINE STRUCTURES OF BOTH INTERFACES AND INTERFACIAL REACTION PRODUCTS
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作者 LI Douxing PING Dehai NING Xiaoguang YE Hengqiang Laboratory of Atomic Imaging of Solids,Institute of Metal Research,Academia Sinica,Shenyang.China Professor,Institute of Metal Research,Academia Sinica,Shenyang 110015,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1993年第1期1-20,共20页
The characteristic of interface depending on the atomic structure exerts an inportant,and sometime controlling,influence on performance of the interacial materials. The present paper reviews the main studies on fine s... The characteristic of interface depending on the atomic structure exerts an inportant,and sometime controlling,influence on performance of the interacial materials. The present paper reviews the main studies on fine structure of both the materials inter- faces and interfacial reaction products in semiconductor uperlattice,metal multilayer ceram- ics and composite materials by mean of selected area electron doffraction patterns and high resolution electron microscopy. The following features of interfaces are reviewed:the orientation relationships;the char- acteristic of steps,facets and ronghness of interfaces;atomic bonding across the interface;the degree of coherency,the structure of misfit dislocations and elastic relaxations at the inter- faces:the presence of defects at the onterfaces:the structure of the interfacial reaction prod- ucts as well as the reaction kinetics and reaetion mechanism. 展开更多
关键词 fine structure of the interfaces interfacial solid state reaction orientation relationship high resolution electron microscopy
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Fine and hyperfine structures of pionic helium atoms
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作者 白志达 钟振祥 +1 位作者 严宗朝 史庭云 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期236-241,共6页
The fine and hyperfine structures of pionic helium metastable states is calculated within the formalism of the Breit-Pauli Hamiltonian by using the variationally generated wave functions in Hylleraas coordinates.Our r... The fine and hyperfine structures of pionic helium metastable states is calculated within the formalism of the Breit-Pauli Hamiltonian by using the variationally generated wave functions in Hylleraas coordinates.Our results not only verify the existing values of Hori et al.[Phys.Rev.A 89,042515(2014)]for the fine structure of π^(4)He^(+),but also determine the hyperfine structure of π^(3)He^(+). 展开更多
关键词 exotic atom pionic helium fine structure hyperfine structure
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TRANSMITTED ELECTRON MICROSCOPY STUDY OF ION-CONTAINING BIOMEDICAL SEGMENTED POLYETHERURETHANE FINE STRUCTURES
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作者 Hui Ying CHEN Jing Jing SU Chemistry Department,Peking University,Beijing 100871Yi Zhu Electron Microscope Laboratory,Peking University 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第3期259-262,共4页
The microphase separation extent of biomedical segmented polyetherurethanes were greatly enhanced due to the presence of sulfoalkyl pendant groups contained in the hard segments,and the hard segments were more orderly... The microphase separation extent of biomedical segmented polyetherurethanes were greatly enhanced due to the presence of sulfoalkyl pendant groups contained in the hard segments,and the hard segments were more orderly aggregated through ionic interaction. 展开更多
关键词 SP Chen ION TRANSMITTED ELECTRON MICROSCOPY STUDY OF ION-CONTAINING BIOMEDICAL SEGMENTED POLYETHERURETHANE fine structures
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Quality Analyses of Fine Structures Transfer in the Photorealistic Images
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作者 S. V. Sai I. S. Sai N. Yu. Sorokin 《Open Journal of Applied Sciences》 2013年第1期6-9,共4页
This work presents method of the quality analyses of the photorealistic images. Developed method utilizes proposed criteria of image definition quality for fine details. Presented method has the following significant ... This work presents method of the quality analyses of the photorealistic images. Developed method utilizes proposed criteria of image definition quality for fine details. Presented method has the following significant property: the quality estimation is provided without test images or patterns. Algorithm for search and recognition of fine structures in the photorealistic images using the predefined criterion is considered. 展开更多
关键词 Image QUALITY ANALYSES SEARCH Algorithm fine structures Recognition
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Interpretation of the pre-edge X-ray absorption fine structures in MnO
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作者 LIShu-Jun HURong +4 位作者 HUTian-Dou XIEYa-Ning ZHANGJing TAOYe WuZi-Yu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2003年第3期153-156,共4页
The weak pre-edge features in the Mn K-edge X-ray absorption near-edge structure (XANES) spectrumof manganese monoxide (MnO) were investigated by comparing experimental data with dipolar and quadrupolarcross-section c... The weak pre-edge features in the Mn K-edge X-ray absorption near-edge structure (XANES) spectrumof manganese monoxide (MnO) were investigated by comparing experimental data with dipolar and quadrupolarcross-section calculations in the framework of multiple-scattering theory. We assign the first pre-edge feature to a di-rect quadrupolar transition from Is core state to 3d molecular orbitals of the central atom, e.g., the lowest in energy,due to the more effective attraction of the core hole. The second peak in this region arises unambiguously from thehybridization between p-orbitals of the central atom with higher-shell metal octahedral orbitals. 展开更多
关键词 X射线吸收微细结构 MNO 氧化亚锰 XAFS 过渡金属元素
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Comparative Studies on the Fine Structure and Elemental Composition of Envelopes of Trachelomonas and Strombomonas (Euglenophyta) 被引量:1
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作者 王全喜 刘洪家 +3 位作者 于晶 孙世琴 张大维 包文美 《Acta Botanica Sinica》 CSCD 2003年第5期601-607,共7页
Fine structure and elemental composition of envelopes of 10 taxa of Trachelomonas and Strombomonas from natural freshwater bodies in China were studied and phylogeny of both genera were discussed. The results indicate... Fine structure and elemental composition of envelopes of 10 taxa of Trachelomonas and Strombomonas from natural freshwater bodies in China were studied and phylogeny of both genera were discussed. The results indicate that iron (Fe) and silicon (Si) are the primary mineral elements of the envelopes. Composition of mineral elements was uncorrelated with envelope color, however, it was highly correlated with the microarchitecture of the envelopes. Content of Si was higher than that of Fe in all species of Strombomonas and some species of Trachelomonas with rough surface. In most species of Trachelomonas, especially those with dense and smoothy surface, content of Fe was higher than that of Si. Based on the above results, we propose to assign those species of Strombomonas into Trachelomonas and consider them as a group of the latter. These species were the most primitive among the group with envelopes in Euglenaceae. 展开更多
关键词 Trachelomonas Strombomonas ENVELOPE elemental composition fine structure
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Periodic oscillation and fine structure of wedge-induced oblique detonation waves 被引量:11
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作者 Ming-Yue Gui Bao-Chun Fan Gang Dong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第6期922-928,共7页
An oblique detonation wave for a Mach 7 inlet flow over a long enough wedge of 30 turning angle is simulated numerically using Euler equation and one-step rection model.The fifth-order WENO scheme is adopted to captur... An oblique detonation wave for a Mach 7 inlet flow over a long enough wedge of 30 turning angle is simulated numerically using Euler equation and one-step rection model.The fifth-order WENO scheme is adopted to capture the shock wave.The numerical results show that with the compression of the wedge wall the detonation wave front structure is divided into three sections:the ZND model-like strcuture,single-sided triple point structure and dual-headed triple point strucuture.The first structure is the smooth straight,and the second has the characteristic of the triple points propagating dowanstream only with the same velocity,while the dual-headed triple point structure is very complicated.The detonation waves facing upstream and downstream propagate with different velocities,in which the periodic collisions of the triple points cause the oscillation of the detonation wave front.This oscillation process has temporal and spatial periodicity.In addition,the triple point trace are recorded to obtain different cell structures in three sections. 展开更多
关键词 Oblique detonation wave Wedge - Periodic oscillation fine structure
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Micro Electrical Discharge Machining Deposition in Air for Fabrication of Micro Spiral Structures 被引量:4
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作者 PENG Zilong CHI Guanxin WANG Zhenlong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第2期154-160,共7页
Micro electrical discharge machining(EDM) deposition process is a new micro machining method for fabrication of metal micro structures. In this process, the high level of tool electrode wear is used to achieve the m... Micro electrical discharge machining(EDM) deposition process is a new micro machining method for fabrication of metal micro structures. In this process, the high level of tool electrode wear is used to achieve the metal material deposition. Up to now, the studies of micro EDM deposition process focused mainly on the researches of deposition process, namely the effects of discharge parameters in deposition process on the deposition rate or deposition quality. The research of the formation of micro structures with different discharge energy density still lacks. With proper conditions and only by the z-axis feeding in vertical direction, a novel shape of micro spiral structure can be deposited, with 0.11 mm in wire diameter, 0.20 mm in outside diameter, and 3.78 mm in height. Then some new deposition strategies including angular deposition and against the gravity deposition were also successful. In order to find the forming mechanism of the spiral structures, the numerical simulation of the transient temperature distribution on the discharge point was conducted by using the finite-element method(FEM). The results show that there are two major factors lead to the forming of the spiral structures. One is the different material removal form of tool electrode according with the discharge energy density, the other is the influenced degree of the movement of the removed material particles in the discharge gap. The more the energy density in single discharge is, the smaller the mass of the removed material particles is, and the easier the movements of which will be changed to form an order tendency. The fine texture characteristics of the deposited micro spiral structures were analyzed by the energy spectrum analysis and the metallographic analysis. It shows that the components of the deposited material are almost the same as those of the tool electrode. Moreover the deposited material has the brass metallic luster in the longitudinal profile and has compact bonding with the base material. This research is useful to understand the micro-process of micro EDM deposition better and helpful to increase the controllability of the new EDM method for fabrication of micro structures. 展开更多
关键词 micro electrical discharge machining deposition micro spiral structure forming mechanism fine texture analysis
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Shell-driven Fine Structure Transition of Core Materials in Co@Au Core-shell Nanoparticles 被引量:1
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作者 Yujun Song Yinghui Wang +1 位作者 Shaoxia Ji Jie Ding 《Nano-Micro Letters》 SCIE EI CAS 2012年第4期235-242,共8页
Co@Au core shell nanoparticles(NPs) of different shell thicknesses were fabricated by a combination of the displacement process and the reduction-deposition process in a microfluidic reactor. The effect of the shell t... Co@Au core shell nanoparticles(NPs) of different shell thicknesses were fabricated by a combination of the displacement process and the reduction-deposition process in a microfluidic reactor. The effect of the shell thickness on the fine structures(local atom arrangement) of core materials was investigated by X-ray Absorption Near Edge Structure(XANES) and Extended X-ray Absorption Fine Structure(EXAFS).The results indicate that the shell thickness affects the fine structure of the core materials by causing atomic re-arrangement between the hexagonal close pack(hcp) and the face centered cubic(fcc) structure, and forming Co-Au bonds in the core-shell interface. 展开更多
关键词 NANOPARTICLE CORE-SHELL fine structure Microfluidic
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Precision calculation of fine structure in helium and Li^+ 被引量:1
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作者 张佩佩 钟振祥 +1 位作者 严宗朝 史庭云 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第3期111-117,共7页
The fine structure constant α can be extracted from high-precision spectroscopy of the 2^3 P J fine structure splittings in helium and light helium-like ions. In this work, the 2^3 P J fine structure splittings of he... The fine structure constant α can be extracted from high-precision spectroscopy of the 2^3 P J fine structure splittings in helium and light helium-like ions. In this work, the 2^3 P J fine structure splittings of helium and Li^+ ion are calculated,including relativistic and QED corrections of order mα^4, mα^4(m/M), mα^5, mα^5(m/M), and Douglas–Kroll operators of mα^6 and mα^6(m/M), which provide an independent verification for the previous calculations performed by Drake [Can.J. Phys. 80 1195(2002)] and by Pachucki and Yerokhin [Phys. Rev. A 79 062516(2009); Phys. Rev. Lett. 104 070403(2010); Can. J. Phys. 89 1139(2011)]. The results of the three groups agree with each other. 展开更多
关键词 fine structure HELIUM Li^+ ion QED theory
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MICROSTRUCTURE TRANSFORMATION IN THE WELDING HEAT AFFECTED ZONE OF 800MPa GRADE ULTRA FINE STRUCTURED STEEL 被引量:1
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作者 J.B. Liu L.J. Hu +3 位作者 Y.T.Wang Z. Q. Liu K. Miao Z.L. Tian 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2004年第3期238-246,共9页
The transformation behavior and microstructure development in the heat affected zone(HAZ)of 800MPa grade ultra fine structured steel was investigated.It was found that the HAZ has intermediate temperature transformati... The transformation behavior and microstructure development in the heat affected zone(HAZ)of 800MPa grade ultra fine structured steel was investigated.It was found that the HAZ has intermediate temperature transformation characteristics in a wide range of cooling rates,with the bainite sheaves consisting of bainite ferrite plates without carbide precipitation and retained austenite in the fast cooling regime.At relatively high cooling rates,which corresponded to low heat inputs,the hardness of the simulated HAZ was above that of the base metal.When the cooling rate was below 9C/s,the welding HAZ would have an obvious softening.The analysis of transformation rates in continuous cooling processes was completed by numerical differential method.The result indicated that the microstructure transformation rate of the HAZ in 800MPa grade ultra fine structured steel changed sharply to slow speeds when the cooling time t8/5 is longer than 7s. 展开更多
关键词 ultra fine structured steel WELD heat affected zone transformation rate microstructure
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Fine Structure of Regenerated Silk Fibroin Solids 被引量:1
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作者 李明忠 吴徵宇 +1 位作者 箕浦宪彦 严灏景 《Journal of Donghua University(English Edition)》 EI CAS 2002年第3期1-6,共6页
The fibroin solids (membrane and gel) were prepared from regenerated silk fibroin solution in different ways. The structure of the fibroin solids and its change during storage were studied. The results indicated that ... The fibroin solids (membrane and gel) were prepared from regenerated silk fibroin solution in different ways. The structure of the fibroin solids and its change during storage were studied. The results indicated that the structure of fibroin membrane air-dried at 30℃ or freeze dried at a freezing temperature of -20-4℃ was the coexistence of amorphous and silkⅠstructure. The amorphous region could partly be transformed into silkⅠstructure under room temperature and humidity. The structure of porous silk fibroin membrane was the coexistence of amorphous and small part of silkⅡ, if the aqueous fibroin was freeze dried within the temperature range of -80℃ to -20℃, and the amorphous partly transformed into silkⅠ during storage. The structure of fibroin gel naturally forming when kept at room temperature was coexistent of amorphous and silkⅡ. The content of Gly and Ala was high in the surface membrane of aqueous fibroin and its structure was mostly silkⅠ and silkⅡwith high crystallinity. 展开更多
关键词 SILK fibroin regenerated fibroin membrane fine structure.
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A New Theory on the Origin and Nature of the Fine Structure Constant 被引量:3
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作者 Nader Butto 《Journal of High Energy Physics, Gravitation and Cosmology》 2020年第4期579-589,共11页
The nature and the origin of the fine structure are described. Based on the vortex model and hydrodynamics, a comprehensible interpretation of the fine structure constant is developed. The vacuum considered to have su... The nature and the origin of the fine structure are described. Based on the vortex model and hydrodynamics, a comprehensible interpretation of the fine structure constant is developed. The vacuum considered to have superfluid characteristics and elementary particles such as the electron and Hydrogen molecule are irrotational vortices of this superfluid. In such a vortex, the angular rotation ω is maintained, and the larger the radius, the slower the rotational speed. The fine structure value is derived from the ratio of the rotational speed of the boundaries of the vortex to the speed of the vortex eye in its center. Since the angular rotation is constant, the same value was derived from the ratio between the radius of the constant vortex core and the radius of the hall vortex. Therefore, the constancy of alpha is an expression of the constancy relation in the vortex structure. 展开更多
关键词 fine structure Constant Angular Rotation Irrotational Vortex Vortex Electron structure Hydrogen Atom structure
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Prediction and Derivation of the Higgs Boson from the Neutron and Properties of Hydrogen Demonstrating Relationships with Planck’s Time, the Down Quark, and the Fine Structure Constant 被引量:2
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作者 Donald William Chakeres 《Journal of Modern Physics》 2014年第16期1670-1683,共14页
A high accuracy Higgs boson, H0, is an important physical constant. The Higgs boson is associated with the property of mass related to broken symmetry in the Standard Model. The H0 mass cannot be derived by the Standa... A high accuracy Higgs boson, H0, is an important physical constant. The Higgs boson is associated with the property of mass related to broken symmetry in the Standard Model. The H0 mass cannot be derived by the Standard Model. The goal of this work is to derive and predict the mass of H0 from the subatomic data of the frequency equivalents of the neutron, electron, Bohr radius, and the ionization energy of hydrogen. H0’s close relationships to the fine structure constant, α, the down quark, and Planck time, tP are demonstrated. The methods of the harmonic neutron hypothesis introduced in 2009 were utilized. It assumes that the fundamental constants as frequency equivalents represent a classic unified harmonic system where each physical constant is associated with a classic harmonic integer fraction. It has been demonstrated that the sum exponent of a harmonic integer fraction, and a small derived linear δ value of the annhilation frequency of the neutron, vn, 2.2718591 × 1023 Hz, (vns) as a dimensionless coupling constant represent many physical constants as frequency equivalents. This is a natural unit system. The harmonic integer fraction series is 1/±n, and 1 ± 1/n for n equals 1 to ∞. The H0 is empirically and logically is associated with harmonic fractions, 1/11 and 1 + 1/11. α-1 is associated with 11. α-1 is a free space scaling constant for the electromagnetic force so it is logical that 11 should also have a pair, but for a free space mass constant. Also there should be a harmonic faction pair for the down quark, 1 - 1/11, just as there is pairing of the up quark, 1 - 1/10, and top quark, 1 + 1/10. The harmonic neutron hypothesis has published a method deriving a high accuracy Planck time, tP from the same limited subatomic data. The δ line for H0 should be closely associated with tP since they both are related to mass. The preferred derived value related to tP2 is 125.596808 GeV/c2. A less attractive derived value is 125.120961 GeV/c2 from the weak force factors only. The experimental CMS and Atlas value ranges are 125.03+0.26+0.13-0.27-0.15 and 125.36±0.37±0.18 GeV/c2. Empirically the H0 δ line is closely related to the same factors of the tP δ line, but with inverse sign of the slope. The H0 completes the paring of a free space constant for mass, the down quark, and an inverse sign δ line factors with tP. It is possible to accurately derive the mass of H0 from subatomic physical data. The model demonstrates that H0 is closely associated with α, the down quark, and tP. This prediction can be scrutinized in the future to see if it is accurate. The model has already published accurate predictions of the masses of the quarks. 展开更多
关键词 Higgs BOSON NEUTRON Unificaiton Model DOWN QUARK fine structure Constant PLANCK TIME Gravity
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