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Representation of three-dimensional mass distribution of the Earth's interior by biorthogonal series and its use for studying internal structure of the planet
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作者 Mykhailo Fys Mariana Yurkiv +1 位作者 Andrii Brydun Andrii Sohor 《Geodesy and Geodynamics》 EI CSCD 2024年第3期264-275,共12页
This paper utilizes the mathematical concept of approximation within an ellipsoid from a single viewpoint to present the spatial mass distribution function of the Earth's interior and its internal potential.The pr... This paper utilizes the mathematical concept of approximation within an ellipsoid from a single viewpoint to present the spatial mass distribution function of the Earth's interior and its internal potential.The primary focus lies in constructing the volume distribution of masses in the planet's interior, with the expansion coefficients being linear combinations of the Stokes constants. Several possible approaches are suggested for determining accurately these coefficients employing three-dimensional(biorthogonal)polynomials. By expressing the mass distribution function of the Earth's interior and its internal potential as a series, an algorithm is introduced for the calculation of gravitational energy. It allows us to estimate fluctuations in gravitational energy. The implementation of this algorithm offers the means of establishing the extent to which the Earth deviates from a state of hydrostatic equilibrium as a celestial body.Due to the aforementioned method, calculations have been conducted to validate its effectiveness and reliability. This example is given as an illustration of a given method for studying the internal structure of planets. 展开更多
关键词 mass distribution function Potential Stokes constants Biorthogonal polynomials
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Pairing effects on the fragment mass distribution of Th,U,Pu,and Cm isotopes
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作者 Xin Guan Jin‑Huan Zheng Mei‑Yan Zheng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第11期128-139,共12页
In this article,a comprehensive study of the fission process of Th,U,Pu,and Cm isotopes using a Yukawa-folded meanfield plus standard pairing model is presented.The study focused on analyzing the effects of the pairin... In this article,a comprehensive study of the fission process of Th,U,Pu,and Cm isotopes using a Yukawa-folded meanfield plus standard pairing model is presented.The study focused on analyzing the effects of the pairing interaction on the fragment mass distribution and its dependence on nuclear elongation.The significant role of pairing interactions in the fragment mass distributions of^(230)Th,^(234)U,^(240)Pu,and^(246)Cm was demonstrated.Numerical analysis revealed that increasing the pairing interaction strength decreased the asymmetric fragment mass distribution and increased the symmetric distribution.Furthermore,the odd-even mass differences at symmetric and asymmetric fission points were examined,highlighting their sensitivity to changes in the pairing interaction strength.Systematic analysis of the Th,U,Pu,and Cm isotope fragment mass distributions demonstrated the effectiveness of the model in reproducing the experimental data.In addition,the effects of the zero-point energy and half-width parameter on the fragment mass distribution for^(240)Pu were explored.Thus,this study provides valuable insights into the fission process by emphasizing the importance of pairing interactions and their relationship with nuclear elongation. 展开更多
关键词 Nuclear fission Pairing interaction Fragment mass distribution Actinide nuclei
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Molar Mass Distribution and Chain Conformation of Polysaccharides from Fortunella margarita(Lour.) Swingle 被引量:3
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作者 曾红亮 张怡 +1 位作者 刘骏 郑宝东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第8期1245-1252,共8页
In order to study the effects of different extraction methods on the molar mass distribution and chain conformation of Fortunella margarita (Lour.) Swingle polysaccharides (FP), we used extraction by hot water (... In order to study the effects of different extraction methods on the molar mass distribution and chain conformation of Fortunella margarita (Lour.) Swingle polysaccharides (FP), we used extraction by hot water (WFP), ultrasonic-assisted treatment (UFP), microwave-assisted treatment (MFP) and ultrasonic/microwave-assisted treatment (UMFP), and then Fourier transform infrared (FT-IR) spectroscopy as well as 1H and 13C nuclear magnetic resonance (NMR) spectroscopy to characterize the structural properties of FP extracted. The molar weight (Mw), polydispersity index (Mw/Mn), root-mean-square (RMS) turning radius (Rg), molar mass distribution and chain conformation of FP were studied systematically using size-exclusion chromatography (SEC), multi-angle laser light-scattering (MALLS) and refractive index (RI). WFP, UFP, MFP and UMFP are all typical carbohydrates according to 1H NMR, laC NMR and FT-IR measurements. The type of glycosidic linkage is mainly a fl-glycosidic bond with a small amount of a-glycosidic bond. The results obtained by the SEC-MALLS-RI system showed the molar masses of WFP and UMFP were distributed mainly in the range of 5.0x10^6-1.0x10^7 g-mo1-1 and they accounted for 57.80% and 56.84% of total FP, respectively. The molar masses of UFP and MFP were distributed mainly in the 1.0x10^6-5.0x10^6 g.mol-1 range, which accounted for 38.24% and 52.39% of FP, respectively. WFP and UMFP in water were uniform spherical polymers; UFP and MFP were typical highly branched polymers and the degree of branching for MFP was higher compared to UFP. These results indicated the ultrasonic- and microwave-assisted extraction methods caused a significant decrease of the molar mass of FP but the ultrasonic/microwave synergistic extraction method had no effect. 展开更多
关键词 Fortunella margarita (Lour.) Swingle polysaccharides molar mass distribution chain conformation
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Pre-neutron-emission mass distributions for reaction ^(238)U(n,f) up to 60 MeV
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作者 孙小军 余呈刚 +2 位作者 王宁 杨永栩 潘成华 《Chinese Physics C》 SCIE CAS CSCD 2015年第1期37-42,共6页
Abstract: The pre-neutron-emission mass distributions for reaction ^238U(n, f) up to 60 MeV are systematically studied with an empirical fission potential model. The energy dependence of the peaks and valleys of th... Abstract: The pre-neutron-emission mass distributions for reaction ^238U(n, f) up to 60 MeV are systematically studied with an empirical fission potential model. The energy dependence of the peaks and valleys of the pre-neutronemission mass distributions is described by an exponential form based on the newly measured data. The energy dependence of evaporation neutrons before scission is also considered, which plays a crucial role in the reasonable description of the mass distributions. The measured ^238U(n, f) are reasonably well reproduced up to 60 predicted using this approach. data of the pre-neutron-emission mass distributions for reaction MeV. The mass distributions at unmeasured energies are also 展开更多
关键词 reaction ^238U(n f) pre-neutron-emission mass distribution evaporation neutron fission potential
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Systematics on fission fragment mass distribution of neutron induced ^(235)U fission
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作者 刘廷进 孙正军 舒能川 《Chinese Physics C》 SCIE CAS CSCD 北大核心 2008年第7期556-560,共5页
Based on the neutron induced fission fragment mass distribution data up to neutron energy 20 MeV measured with the double kinetic energy method (KEM) and the radio active method (RAM), the systematics of fission f... Based on the neutron induced fission fragment mass distribution data up to neutron energy 20 MeV measured with the double kinetic energy method (KEM) and the radio active method (RAM), the systematics of fission fragment mass distribution was investigated by using 5 Gaussian model and the systematics parameters were obtained by fitting the experimental data. With the systematics, the yields of any mass A and at any energy in the region from 0 to 20 MeV of neutron energy can be calculated. The calculated results could well reproduce the experimental data measured with KEM, but show some systematical deviation from the data measured by RAM, which reflects some systematical deviations between the two kinds of measured data. The error of systematics yield was calculated in an exact error transformation way, including from the error of the experimental yield data to the error of the discrete parameters, then to the systematics parameters, and at last to the yield calculated with systematics. 展开更多
关键词 235U fission fission fragment mass distribution SYSTEMATICS 5 Gaussian model
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Relative Molecular Mass Distribution of BG Resins
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作者 高彦芳 许越平 刘德山 《Tsinghua Science and Technology》 SCIE EI CAS 1999年第2期79-81,共3页
Benzoguanamine formaldehyde (BG F) resins are a class of amino resins, which are important cross linking agents for epoxy, alkyol and acrylic resins, etc. The cross linking performance is the best one when the polymer... Benzoguanamine formaldehyde (BG F) resins are a class of amino resins, which are important cross linking agents for epoxy, alkyol and acrylic resins, etc. The cross linking performance is the best one when the polymerization degree is 2 4. This paper discusses the effects of the pH value for polycondensation and the formaldehyde to benzoguanamine mole ratio in a methanol system, and compares the relative molecular mass distribution using the Flory statistics method. 展开更多
关键词 benzoguanamine formaldehyde resins homogeous system relative molecular mass distribution
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Phenolic metabolism and molecular mass distribution of polysaccharides in cellulose-deficient maize cells
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作者 María de Castro Romina Martínez-Rubio +3 位作者 José L.Acebes Antonio Encina Stephen C.Fry Penélope García-Angulo 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2017年第7期475-495,共21页
As a consequence of the habituation to low levels of dichlobenil (DCB), cultured maize cells presented an altered hemicellulose cell fate with a lower proportion of strongly wall-bound hemicelluloses and an increase... As a consequence of the habituation to low levels of dichlobenil (DCB), cultured maize cells presented an altered hemicellulose cell fate with a lower proportion of strongly wall-bound hemicelluloses and an increase in soluble extracellular polymers released into the culture medium. The aim of this study was to investigate the relative molecular mass distributions of polysaccharides as well as phenolic metabolism in cells habituated to low levels of DCB (1.5 μM). Generally, cell wall bound hemicelluloses and sloughed polymers from habituated cells were more homogeneously sized and had a lower weight-average relative molecular mass. In addition, polysaccharides underwent massive cross-linking after being secreted into the cell wall, but this cross-linking was less pronounced in habituated cells than in non-habituated ones. However, when relativized, ferulic acid and p-coumaric acid contents were higher in this habituated cell line. Feasibly, cells habituated to low levels of DCB synthesized molecules with a lower weight-average relative molecular mass, although cross-linked, as a part of their strategy to compensate for the lack of cellulose. 展开更多
关键词 Phenolic metabolism and molecular mass distribution of polysaccharides in cellulose-deficient maize cells were for
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Evaluation of pre-neutron-emission mass distributions of neutron-induced typical actinide fission using scission point model
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作者 霍东英 杨旭 +12 位作者 韩超 刘昌奇 吴康 刘兴宇 黄畅 谢芹 何源 包小军 姚泽恩 张宇 王俊润 苏小东 韦峥 《Chinese Physics C》 SCIE CAS CSCD 2021年第11期128-135,共8页
The scission point model is improved by considering the excitation-dependent liquid drop model to calculate mass distributions for neutron-induced actinide nuclei fission.Excitation energy effects influence the deform... The scission point model is improved by considering the excitation-dependent liquid drop model to calculate mass distributions for neutron-induced actinide nuclei fission.Excitation energy effects influence the deformations of light and heavy fragments.The improved scission point model shows a significant advance with regard to accuracy for calculating pre-neutron-emission mass distributions of neutron-induced typical actinide fission with incident-neutron-energies up to 99.5 MeV.The theoretical frame assures that the improved scission point model is suitable for evaluating the fission fragment mass distributions,which will provide guidance for studying fission physics and designing nuclear fission engineering and nuclear transmutation systems. 展开更多
关键词 mass distributions scission-point model dinuclear system model
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Construction of high-resolution energy-time-of-flight spectrometer for determination of fission fragmentmass distributions
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作者 Chao Liu Shilong Liu Yi Yang 《Radiation Detection Technology and Methods》 CSCD 2022年第1期102-110,共9页
Purpose With the aim of determining mass yield distributions of primary fission products,a one-arm spectrometer was developed based on kinetic energy and time-of-flight correlation measurement technique.Methods An axi... Purpose With the aim of determining mass yield distributions of primary fission products,a one-arm spectrometer was developed based on kinetic energy and time-of-flight correlation measurement technique.Methods An axial grid ionization chamber(GIC)was designed for energy detecting.In order to minimize energy losses and straggling,a thin silicon nitride film with a thickness of 100 nm was performed as the entrance window of the GIC.The energy resolution is 0.38%for 80 MeV ^(63)Cu particles.Two-timing detectors based on the detection of secondary emission electrons by microchannel plates(MCPs)constitute the time pick-off system,and the time-of-flight resolution is better than 200 ps(FWHM)measured with a ^(241)Amαsource.With a flight path length of 47.6 cm,the path length resolution is 0.21%.Results and conclusion The first result of mass distribution from ^(252)Cf spontaneous fission was reported.Energy losses of fragments in dead layers of the spectrometer were corrected event-by-event depend on the Monte Carlo calculation.The mass resolution for light fission fragments peak A107 amu is 1.3 aum. 展开更多
关键词 ^(252)Cf spontaneous fission Fission product mass distribution Grid ionization chamber TIME-OF-FLIGHT Monte Carlo calculation
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Configurational information entropy analysis of fragment mass cross distributions to determine the neutron skin thickness of projectile nuclei 被引量:4
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作者 Hui-Ling Wei Xun Zhu Chen Yuan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第9期21-27,共7页
Configurational information entropy(CIE)analysis has been shown to be applicable for determining the neutron skin thickness(δnp)of neutron-rich nuclei from fragment production in projectile fragmentation reactions.Th... Configurational information entropy(CIE)analysis has been shown to be applicable for determining the neutron skin thickness(δnp)of neutron-rich nuclei from fragment production in projectile fragmentation reactions.The BNN+FRACS machine learning model was adopted to predict the fragment mass cross-sections(σ_(A))of the projectile fragmentation reactions induced by calcium isotopes from ^(36)Ca to ^(56)Ca on a ^(9)Be target at 140MeV/u.The fast Fourier transform was adopted to decompose the possible information compositions inσA distributions and determine the quantity of CIE(S_(A)[f]).It was found that the range of fragments significantly influences the quantity of S_(A)[f],which results in different trends of S_(A)[f]~δnp correlation.The linear S_(A)[f]~δnp correlation in a previous study[Nucl.Sci.Tech.33,6(2022)]could be reproduced using fragments with relatively large mass fragments,which verifies that S_(A)[f]determined from fragmentσAis sensitive to the neutron skin thickness of neutron-rich isotopes. 展开更多
关键词 Neutron skin thickness mass cross-section distribution Configurational information entropy Projectile fragmentation reaction
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Characteristics of mass distributions of aerosol particle and its inorganic water-soluble ions in summer over a suburb farmland in Beijing 被引量:2
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作者 ZHAO Peng ZHU Tong +3 位作者 LIANG Baosheng HU Min KANG Ling GONG Jicheng 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2007年第2期159-165,共7页
Agricultural activity is one of the most important sources of aerosol particles.To understand the mass distribu-tion and sources of aerosol particles and their inorganic water-soluble ions in a suburb farmland of Beij... Agricultural activity is one of the most important sources of aerosol particles.To understand the mass distribu-tion and sources of aerosol particles and their inorganic water-soluble ions in a suburb farmland of Beijing,particle samples were collected using a microorifice uniform deposit impactor(MOUDI)in the summer of 2004 in a suburb vege-table field.The distribution of the particles and their inor-ganic water-soluble ions in the diameter range of 0.18-18 mm were measured.The dominant fine particle ions were SO_(4)^(2−),NO^(3−),and NH_(4)^(+).The association of day-to-day variation of the concentration of these ions with temperature,humidity,and solar radiation suggested that they are formed by the reac-tion of NH_(3) released from the vegetable field with the acid species produced from photochemical reactions.Fine particle K+is likely from vegetation emission and biomass burning.Coarse particles like Ca^(2+),Mg^(2+),NO_(3)^(−),and SO_(4)^(2−)are sug-gested to come from the mechanical process by which the soil particle entered the atmosphere,and from the reaction of the acid species at the surface of the soil particle.The results show that fertilizer and soil are important factors determining the aerosol particle over agricultural fields,and vegetable fields in suburban Beijing contribute significantly to the aerosol particle. 展开更多
关键词 mass size distribution coarse particle fine particle source
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Preliminary analysis of distribution and variation of perennialmonthly mean water masses in the Bohai Sea,the Huanghai Sea and the East China Sea 被引量:6
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作者 Liu Shuxun, Shen Xinqiang, Wang Youqin and Han Shixin 1. East China Sea Fisheries Research Institute, No. 300, Jungong Road, Shanghai 200090, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第4期483-498,共16页
On the basis of perennial monthly mean temperature and salinity data, the classification of monthly water masses at the surface and the bottom in the Bohai Sea, the Huanghai Sea and the East China Sea, has been made b... On the basis of perennial monthly mean temperature and salinity data, the classification of monthly water masses at the surface and the bottom in the Bohai Sea, the Huanghai Sea and the East China Sea, has been made by using the method of fuzzy cluster from the modified characteristic of water masses in the shallow water area. In this paper, the basic features, growth and decline patterns of water masses in relation to fishing grounds in the whole shelves of the Bohai Sea, the Huanghai Sea and the East China Sea are discussed with emphasis. 展开更多
关键词 Preliminary analysis of distribution and variation of perennialmonthly mean water masses in the Bohai Sea the Huanghai Sea and the East China Sea
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UHAS-MIDA Software Package: Mass Isotopomer Distribution Analysis-Applying the Inverse Matrix for the Determination of Stable Isotopes of Chromium Distribution during Red Blood Cell Labelling
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作者 Daniel A. Abaye Emmanuel B. Odoom +3 位作者 Ernest Y. Boateng Irene A. Agbo John-Bosco Diekuu Samuel Agana 《Journal of Data Analysis and Information Processing》 2022年第2期142-154,共13页
Clinical assessment of fluid volume status in children during malaria can be taxing and often inaccurate. During malaria, changes in fluid volume are rather multifarious and estimating this parameter, especially in si... Clinical assessment of fluid volume status in children during malaria can be taxing and often inaccurate. During malaria, changes in fluid volume are rather multifarious and estimating this parameter, especially in sick children is very challenging for clinicians who frequently rely on indices such as long capillary refill times, tachycardia, central venous pressure and decreased urine volume as guides. Here, we present the UHAS-MIDA, an open-source software tool that calculates the red blood cell (RBC) concentration and blood volume during malaria in children determined using a stable isotope of chromium (<sup>53</sup>Cr as the label) by gas chromatography-mass spectrometry in selective ion monitoring (GC/MS-SIM) analysis. A key component involves the determination of the compositions of the most abundant naturally occurring isotopes of Cr (<sup>50</sup>Cr, <sup>52</sup>Cr, <sup>53</sup>Cr), and converting the proportions into a 3 × 3 matrix. To estimate unknown proportions of chromium isotopic mixtures from the measured abundances of three ions, an inverse matrix was calculated. The inverse together with several inputs is then used to calculate the corrected MS ion abundances. Thus, we constructed the software tool UHAS- MIDA using HTML, CSS/Bootstrap, JavaScript, and PHP scripting languages. The tool enables the user to efficiently determine RBC concentration and fluid volume. The source code, binary packages and associated materials for UHAS-MIDA are freely available at https://github.com/bentil078/Abaye-et-al_UHASmida 展开更多
关键词 mass Isotopomer distribution Analysis Inverse Matrix GC/MS Chromium Stable Isotopes Blood Volume Red Blood Cell mass
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Approximate energies and thermal properties of a position-dependent mass charged particle under external magnetic fields
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作者 M Eshghi H Mehraban S M Ikhdair 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期22-30,共9页
We solve the Schrodinger equation with a position-dependent mass(PDM) charged particle interacted via the superposition of the Morse-plus-Coulomb potentials and is under the influence of external magnetic and Aharo... We solve the Schrodinger equation with a position-dependent mass(PDM) charged particle interacted via the superposition of the Morse-plus-Coulomb potentials and is under the influence of external magnetic and Aharonov–Bohm(AB) flux fields. The nonrelativistic bound state energies together with their wave functions are calculated for two spatially-dependent mass distribution functions. We also study the thermal quantities of such a system. Further, the canonical formalism is used to compute various thermodynamic variables for second choosing mass by using the Gibbs formalism. We give plots for energy states as a function of various physical parameters. The behavior of the internal energy, specific heat, and entropy as functions of temperature and mass density parameter in the inverse-square mass case for different values of magnetic field are shown. 展开更多
关键词 Schr?dinger equation Morse-plus-Coulomb potentials position-dependent mass distribution functions perpendicular magnetic and Aharonov–Bohm flux fields
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Working Fluid Distribution and Charge Regulation Control in Organic Rankine Cycle
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作者 叶振鸿 李新华 +1 位作者 王炜 陈江平 《Journal of Shanghai Jiaotong university(Science)》 EI 2024年第2期188-201,共14页
Charge-based studies,in particular investigations of mass distribution,are still almost absent,although the efficiency of the organic Rankine cycle(ORC)has attracted a great deal of scholarly attention.This paper aims... Charge-based studies,in particular investigations of mass distribution,are still almost absent,although the efficiency of the organic Rankine cycle(ORC)has attracted a great deal of scholarly attention.This paper aims to provide a new perspective on the intrinsic relationship among the mass distribution,phase-zone distribution in the heat exchanger(HEX),charge of working fuid(WF),rotation speed of the pump(RSP),and system performance.A comprehensive ORC simulation model is presented by linking each component's sub-models,including the independent models for HEX,pump,and expander in an object-oriented fashion.The visualization study of mass distribution of the WF in the system is investigated under different working conditions.Furthermore,the volume and mass of the gas phase,two-phase and liquid phase of WF in the HEX and their variation rules are analyzed in-depth.Finally,the strategies of charge reduction considering HEX areas and pipe sizes are investigated.The results show that the model based on the interior-point method provides high levels of accuracy and robustness.The mass ratio of the WF is concentrated in the liquid receiver,especially in the regenerator,which is 32.9%and 21.9%of the total mass,respectively.Furthermore,2.4 kg(6.9%)WF in the system gradually migrates to the high-temperature side as the RSP increases while 6.1 kg(17.4%)WF migrates to the low-temperature side,especially to the condenser,as the charge in the system increases.Output power and efficiency both decrease gradually after the peak due to changes in RSP and charge.Last,reducing heat transfer areas of the condenser and regenerator is the most effective way to reduce WF charge. 展开更多
关键词 SIMULATION organic Rankine cycle(ORC) working fuid charge mass distribution
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磷酸化肽段质量数的分布特征
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作者 魏开华 刘锋 +4 位作者 何昆 王杰 刘炳玉 张学敏 杨松成 《分析测试学报》 CAS CSCD 北大核心 2004年第z1期72-73,共2页
  基于双向电泳和液相色谱的蛋白质鉴定是蛋白质组最常用的技术,质谱谱图的好坏对鉴定的成功率起决定性作用.其中,某些不确定的修饰和非蛋白污染物是影响谱图质量的难以忽略的因素.……
关键词 Peptide mass distribution Protein modification PMF
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Long-term gravity changes in Chinese mainland from GRACE and ground-based gravity measurements 被引量:3
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作者 Xing Lelin Li Hui +2 位作者 Xuan Songbai Kang Kaixuan Liu Xiaoling 《Geodesy and Geodynamics》 2011年第3期61-70,共10页
A long-term (9 years) gravity change in Chinese mainland is obtained on the basis of observation of the ground-based national gravity network. The result shows several features that may be related to sore, large-sca... A long-term (9 years) gravity change in Chinese mainland is obtained on the basis of observation of the ground-based national gravity network. The result shows several features that may be related to sore, large-scale groundwater pumping in North China, glacier-water flow and storage in Tianshan region, and pre seismic gravity changes of the 2008 MsS. 0 Wenchuan earthquake, which are spatially similar to co-seismi, changes but reversed in sign. These features are also shown in the result of the satellite-based GRACE obser vation, after a height effect is corrected with GPS data. 展开更多
关键词 GRACE ground-based gravity measurement mass distribution EARTHQUAKE
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Fermion or Boson Dark Matter? 被引量:2
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作者 Bruce Hoeneisen 《International Journal of Astronomy and Astrophysics》 2020年第3期203-223,共21页
We measure properties of dark matter in four well motivated scenarios: fermions with ultra-relativistic thermal equilibrium (URTE), bosons with URTE, fermions with non-relativistic thermal equilibrium (NRTE), and boso... We measure properties of dark matter in four well motivated scenarios: fermions with ultra-relativistic thermal equilibrium (URTE), bosons with URTE, fermions with non-relativistic thermal equilibrium (NRTE), and bosons with NRTE. We attempt to discriminate between these four scenarios with studies of spiral galaxy rotation curves, and galaxy stellar mass distributions. The measurements show evidence for boson dark matter with a significance of 3.5σ, and obtain no significant discrimination between URTE and NRTE. 展开更多
关键词 Dark Matter Free-Streaming Galaxy mass distribution Spiral Galaxy
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Comments on Warm Dark Matter Measurements and Limits 被引量:3
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作者 Bruce Hoeneisen 《International Journal of Astronomy and Astrophysics》 2022年第1期94-109,共16页
Observed spiral galaxy rotation curves allow a measurement of the warm dark matter particle velocity dispersion and mass. The measured thermal relic mass m<sub>h </sub>&asymp;100 eV is in disagreement ... Observed spiral galaxy rotation curves allow a measurement of the warm dark matter particle velocity dispersion and mass. The measured thermal relic mass m<sub>h </sub>&asymp;100 eV is in disagreement with limits, typically in the range 1 to 4 keV. We review the measurements, update the no freeze-in and no freeze-out scenario of warm dark matter, and try to identify the cause of the discrepancies between measurements and limits. 展开更多
关键词 Warm Dark Matter Spiral Galaxy Rotation Curves Stellar mass distributions Lyman-α Forest
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Electrophoresis(SDS-PAGE)as a Method for Screening Species of Passiflora Using Seed Proteins as Molecular Markers
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作者 Marilia Penteado Stephan Ana Maria Costa +3 位作者 Tatiana De Lima Azevedo Jeane Santos Da Rosa Alexsandro Araújo Dos Santos 《Journal of Agricultural Science and Technology(B)》 2022年第2期40-47,共8页
Brazil is the center of diversity and dispersion of species of the genus Passiflora.Two species of passion fruit Passiflora tenuifila BRS VT(passiflora garlic)and another of Passiflora setacea BRS PC were used in this... Brazil is the center of diversity and dispersion of species of the genus Passiflora.Two species of passion fruit Passiflora tenuifila BRS VT(passiflora garlic)and another of Passiflora setacea BRS PC were used in this study.The plants were grown on the Embrapa Cerrados experimental farm.The fruits were washed,minimally cut and their constituents separated.Both species differed in the proportion of wet mass between husk,seed,and pulp.As expected,both species had a higher proportion of husks and seeds and a lower amount of pulp.A semi-purification procedure for the proteins present in the seeds and husks was described and the molecular aspects were analyzed by polyacrylamide gel electrophoresis(SDS-PAGE).The quantification of soluble proteins was performed using the Bradford method.The analysis of the soluble protein extracted from the seeds and husks showed that these values are up to 70 times higher for the seeds of P.tenuifila and 28.5 times for P.setacea,in the husks.It was verified that both species present a similar protein profile,observed by the intense and diverse bands found in the polyacrylamide gel,mainly in the range of 32 to 19 kDa.This work opens up an unexplored field of tracking bioactive proteins and/or peptides including forms of nanostructure systems that protect other bioactive molecules.The objective of this work was to present an analytical procedure to semi-purify seed proteins of two Passiflora species and use electrophoresis as an analysis tool for further screening of their protein profiles and selection of a molecular marker to differentiate them. 展开更多
关键词 Protein screening method bioactive peptides SEEDS P.setacea P.tenuifila mass distribution on fruit
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