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Assessment of Patentability of Inventions Relating to "Rules and Methods for Mental Activities" 被引量:3
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作者 Cui Aiping Examiner of the Communication Department of the Patent Office of the State Intellectual Property Office 《中国专利与商标》 2006年第4期46-51,共6页
Examination of whether an invention is a patentable subject matter or not is one of the main parts of the patent examination. In the recently revised Guidelines for Examination a relatively major change has been made ... Examination of whether an invention is a patentable subject matter or not is one of the main parts of the patent examination. In the recently revised Guidelines for Examination a relatively major change has been made of the benchmark for the examination of inventions relating to "rules and methods for mental activities", for example, limiting the scope of application of Article 25.1 (2) of the Patent Law. As a result, the hitherto non-patentable subject matters are still excluded from patentability. That... 展开更多
关键词 Rules and methods for Mental Activities MODE
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Piezoelectric Actuator/Sensor Wave Propagation Based Nondestructive Active Monitoring Method of Concrete Structures 被引量:5
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作者 朱劲松 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第3期541-547,共7页
In order to monitor the basic mechanical properties and interior damage of concrete structures,the piezoelectric actuator/sensor based wave propagation method was investigated experimentally in the laboratory using a ... In order to monitor the basic mechanical properties and interior damage of concrete structures,the piezoelectric actuator/sensor based wave propagation method was investigated experimentally in the laboratory using a specifically designed test setup.The energy attenuation of stress waves was measured by the relative index between the output voltage of sensors and the excitation voltage at the actuator.Based on the experimental results of concrete cube and cylinder specimens,the effect of excitation frequencies,excitation amplitude,wave propagation paths and the curing age on the output signals of sensors are evaluated.The results show that the relative voltage attenuation coefficient RVAC is an effective indicator for measuring the attenuation of stress waves through the interior of concrete. 展开更多
关键词 piezoceramics actuator/sensor wave propagation method non-destructive evaluation (NDE) active monitoring concrete
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Parametric vibration stability and active control of nonlinear beams
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作者 李凤明 刘春川 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第11期1381-1392,共12页
The vibration stability and the active control of the parametrically excited nonlinear beam structures are studied by using the piezoelectric material. The velocity feedback control algorithm is used to obtain the act... The vibration stability and the active control of the parametrically excited nonlinear beam structures are studied by using the piezoelectric material. The velocity feedback control algorithm is used to obtain the active damping. The cubic aonlineax equation of motion with damping is established by employing Hamilton's principle. The multiple-scale method is used to solve the equation of motion, and the stable region is obtained. The effects of the control gain and the amplitude of the external force on the stable region and the amplitude-frequency curve axe analyzed numerically. From the numerical results, it is seen that, with the increase in the feedback control gain, the axial force, to which the structure can be subjected, is increased, and in a certain scope, the structural active damping ratio is also increased. With the increase in the control gain, the response amplitude decreases gradually, but the required control voltage exists a peak value. 展开更多
关键词 BEAM piezoelectric material parametric vibration STABILITY active control multiple-scale method
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Improved Active Islanding Detection Technique for Multi-Inverter Power System
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作者 Jie Zhang Yu-Hua Cheng +1 位作者 Kai Chen Gen Qiu 《Journal of Electronic Science and Technology》 CAS CSCD 2021年第2期186-195,共10页
Due to the increased penetration of multi-inverter distributed generation(DG)systems,different DG technologies,inverter control methods,and other inverter functions are challenging the capabilities of islanding detect... Due to the increased penetration of multi-inverter distributed generation(DG)systems,different DG technologies,inverter control methods,and other inverter functions are challenging the capabilities of islanding detection.In addition,multi-inverter networks connecting the distribution system point of common coupling(PCC)create islanding at paralleling inverters,which adds the vulnerability of islanding detection.Furthermore,available islanding detection must overcome more challenges from non-detection zones(NDZs)under reduced power mismatches.Therefore,in this study,a new method called parameter self-adapting active islanding detection was utilized to minimize the dilution effect and reduce NDZs in multi-inverter power systems.The method utilizes an active frequency drift(AFD)method and applies a positive feedback gain of adoption parameters,which significantly minimizes NDZs at parallel inverters.The simulation and experimental outcomes indicate that the proposed method can effectively weaken the dilution effect in multi-inverter networks connecting the distribution system PCC. 展开更多
关键词 active frequency drift(AFD) active islanding detection method multi-inverter power system non-detection zones(NDZs)
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Comparative Study of the Geomagnetic Activity Effect on foF2 Variation as Defined by the Two Classification Methods at Dakar Station over Solar Cycle Phases
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作者 Sibri Alphonse Sandwidi Doua Allain Gnabahou Frédéric Ouattara 《International Journal of Geosciences》 2020年第8期501-517,共17页
This paper aims to establish a comparison between both geomagnetic activity classification methods on foF2 diurnal variation over solar cycle phases. It concerns first a comparison of geomagnetic activity occurrences ... This paper aims to establish a comparison between both geomagnetic activity classification methods on foF2 diurnal variation over solar cycle phases. It concerns first a comparison of geomagnetic activity occurrences according to both classification methods;and second the geomagnetic effect on foF2 diurnal variation profiles as defined for the equatorial latitudes. The occurrences of the different disturbed geomagnetic activities (recurrent activity (RA), shock activity (SA) and fluctuant activity (FA)) according to both classifications (ancient classification (AC) and new classification (NC)) have been studied at Dakar ionosonde station (Lat: 14.8°N;Long: 342.6°E). Regarding both classifications, the RA occurs more during the decreasing phase. And it’s observed that the RA occurs the most during the increasing phase for the AC and during the minimum phase for the NC. The maximum gap of occurrence (<img src="Edit_e4627ea9-9a9a-4473-9017-202d04a16377.bmp" alt="" /><span><span style="font-family:Verdana;">) between both classifications is <span style="font-size:10.0pt;font-family:;" "=""><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">&#45</span></span></span><span style="font-family:;" "=""><span style="font-family:Verdana;">11.1%</span><span style="font-family:Verdana;"> (for the negative value which is observed during the increasing phase) and </span><span style="font-family:Verdana;">+16.74%</span><span style="font-family:Verdana;"> (for the positive one which is observed during the decreasing phase). The occurrence of the SA in relation with both classifications is the lowest during the minimum phase and the maximum occurrence is observed during the maximum and decreasing phases, for the AC, with a value close to </span><span style="font-family:Verdana;">37%</span><span style="font-family:Verdana;"> and for the NC at the maximum phase with a percentage of </span><span style="font-family:Verdana;">54.47%</span><span><span style="font-family:Verdana;">. The maximum gap of occurrence (</span><img src="Edit_20fa141b-ecee-4e06-8024-144ba0969395.bmp" alt="" /></span></span><span style="font-family:Verdana;">) between both classifications is <span style="font-size:10.0pt;font-family:;" "=""><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">&#45</span></span></span><span style="font-family:;" "=""><span style="font-family:Verdana;">17.85%</span><span style="font-family:Verdana;"> (for the negative value which is observed at maximum phase) and </span><span style="font-family:Verdana;">+13.53%</span><span style="font-family:Verdana;"> (for the positive one which is observed during the decreasing phase). For both classifications, the FA occurs the least during the minimum phase and the most during the maximum phase for the AC and at maximum and decreasing phases with percentage values of occurrence of roughly </span><span style="font-family:Verdana;">37%</span><span><span style="font-family:Verdana;"> for the NC. The maximum gap of occurrence (</span><img src="Edit_eecb8939-783e-4d43-b92c-80c528c1890b.bmp" alt="" /><span style="font-family:Verdana;"></span></span></span><span style="font-family:Verdana;">) between both classifications is <span style="font-size:10.0pt;font-family:;" "=""><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">&#45</span></span>10% (for the negative value which is observed during the decreasing phase) and </span><span style="font-family:;" "=""><span style="font-family:Verdana;">+20.11%</span><span style="font-family:Verdana;"> (for the positive one which is observed during the maximum phase). foF2 diurnal profiles throughout solar cycle phases concerning the AC and the NC have been compared. The FA diurnal profiles don’t present a difference. The RA and the SA present a difference during minimum and increasing phases and the least at maximum and decreasing phases.</span></span></span> 展开更多
关键词 Geomagnetic Activity Classification Method Solar Cycle Phases foF2 Diurnal Profile
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An experimental indoor phasing system based on active optics using dispersed Hartmann sensing technology in the visible waveband
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作者 Yong Zhang Gen-Rong Liu +5 位作者 Yue-Fei Wang Ye-Ping Li Ya-Jun Zhang Liang Zhang Yi-Zhong Zeng Jie Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第9期1111-1122,共12页
A telescope with a larger primary mirror can collect much more light and resolve objects much better than one with a smaller mirror, and so the larger version is always pursued by astronomers and astronomical technici... A telescope with a larger primary mirror can collect much more light and resolve objects much better than one with a smaller mirror, and so the larger version is always pursued by astronomers and astronomical technicians. Instead of using a monolithic primary mirror, more and more large telescopes, which are currently being planned or in construction, have adopted a segmented primary mirror design. Therefore, how to sense and phase such a primary mirror is a key issue for the future of extremely large optical/infrared telescopes. The Dispersed Fringe Sensor (DFS), or Dispersed Hartmann Sensor (DHS), is a non-contact method using broadband point light sources and it can estimate the piston by the two-directional spectrum formed by the transmissive grating's dispersion and lenslet array. Thus it can implement the combination of co-focusing by Shack-Hartmann technology and phasing by dispersed fringe sensing technologies such as the template-mapping method and the Hartmann method. We introduce the successful design, construction and alignment of our dis- persed Hartmann sensor together with its design principles and simulations. We also conduct many successful real phasing tests and phasing corrections in the visible waveband using our existing indoor segmented mirror optics platform. Finally, some conclusions are reached based on the test and correction of experimental results. 展开更多
关键词 astronomical instrumentation -- methods and techniques -- instrumen- tation: active optics -- adaptive optics
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Low-temperature Denitration Mechanism of NH_(3)-SCR over Fe/AC Catalyst
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作者 杨征宇 黄帮福 +3 位作者 ZHANG Guifang DAI Meng WEN Zhenjing LI Wanjun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期475-484,共10页
To study the modification mechanism of activated carbon(AC)by Fe and the low-temperature NH_(3)-selective catalytic reduction(SCR)denitration mechanism of Fe/AC catalysts,Fe/AC catalysts were prepared using coconut sh... To study the modification mechanism of activated carbon(AC)by Fe and the low-temperature NH_(3)-selective catalytic reduction(SCR)denitration mechanism of Fe/AC catalysts,Fe/AC catalysts were prepared using coconut shell AC activated by nitric acid as the support and iron oxide as the active component.The crystal structure,surface morphology,pore structure,functional groups and valence states of the active components of Fe/AC catalysts were characterised by X-ray diffraction,scanning electron microscopy,nitrogen adsorption and desorption,Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy,respectively.The effect of Fe loading and calcination temperature on the low-temperature denitration of NH_(3)-SCR over Fe/AC catalysts was studied using NH_(3)as the reducing gas at low temperature(150℃).The results show that the iron oxide on the Fe/AC catalyst is spherical and uniformly dispersed on the surface of AC,thereby improving the crystallisation performance and increasing the number of active sites and specific surface area on AC in contact with the reaction gas.Hence,a rapid NH_(3)-SCR reaction was realised.When the roasting temperature remains constant,the iron oxide crystals formed by increasing the amount of loading can enter the AC pore structure and accumulate to form more micropores.When the roasting temperature is raised from 400 to 500℃,the iron oxide is mainly transformed fromα-Fe_(2)O_(3)toγ-Fe_(2)O_(3),which improves the iron oxide dispersion and increases its denitration active site,allowing gas adsorption.When the Fe loading amount is 10%,and the roasting temperature is 500℃,the NO removal rate of the Fe/AC catalyst can reach 95%.According to the study,the low-temperature NH_(3)-SCR mechanism of Fe/AC catalyst is proposed,in which the redox reaction between Fe~(2+)and Fe~(3+)will facilitate the formation of reactive oxygen vacancies,which increases the amount of oxygen adsorption on the surface,especially the increase in surface acid sites,and promotes and adsorbs more reaction gases(NH_(3),O_(2),NO).The transformation from the standard SCR reaction to the fast SCR reaction is accelerated. 展开更多
关键词 nitric acid activation method coconut shell activated carbon Fe/AC catalyst NH_(3)-SCR low-temperature denitrification mechanism
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基于零点配置的分力合成主动振动抑制方法研究(英文) 被引量:4
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作者 张建英 刘暾 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第4期304-312,共9页
The component synthesis active vibration suppression method (CSVS) can be applied to suppress the vibration of flexible systems. By this method, several same or similar time-varying components are arranged according... The component synthesis active vibration suppression method (CSVS) can be applied to suppress the vibration of flexible systems. By this method, several same or similar time-varying components are arranged according to certain rules along the time axis. The synthesized command can suppress the arbitrary unwanted vibration harmonic while achieving the desired rigid body motion. The number of the components increases rapidly when the number of harmonic vibration is growing. In this article, the CSVS based on zero-placement technique is used to construct the synthesized command to suppress the multi-harmonics simultaneously in the discrete domain. The nature of zero-placement method is to put enough zeros to cancel system poles at necessary points. The designed synthesized command has equal time intervals between each component and which is much easier to be implemented. Using this method, the number of components increases linearly with the increasing of the number of being suppressed harmonics. For the spacecraft with flexible appendages, CSVS based on zero-placement is used to design the time optimal large angle maneuver control strategy. Simulations have verified the validity and superiority of the proposed approach. 展开更多
关键词 flexible structure vibration suppression component synthesis active vibration suppression method zero-placement technique
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Optical quasi-periodic oscillation and color behavior of blazar PKS 2155–304 被引量:5
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作者 Bing-Kai Zhang Xiao-Yun Zhao +1 位作者 Chun-Xiao Wang Ben-Zhong Dai 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第8期933-941,共9页
PKS 2155-304 is a well studied BL Lac object in the southern sky. The historical optical data during different periods have been collected and compiled. Light curves spanning 35 yr have been constructed. The R-band li... PKS 2155-304 is a well studied BL Lac object in the southern sky. The historical optical data during different periods have been collected and compiled. Light curves spanning 35 yr have been constructed. The R-band light curve has been ana- lyzed by means of three methods: the epoch folding method, the Jurkevich method and the discrete correlation function method. It is derived that there is an evident periodic component of 317 d (i.e. 0.87 yr) superposed on a long-term trend with large- amplitude variation in the light curve. The variability of this source is accompanied by a slight color variation, and the brightness and color index are correlated with each other. On a long-term time scale, PKS 2155-304 exhibits a tendency of bluer-when- brighter, which means the spectrum becomes flatter when the source brightens. 展开更多
关键词 BL Lacertae objects general -- BL Lacertae objects individual (PKS 2155-304) -- galaxies active -- method statistical
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Wavelet Analysis of Several Important Periodic Properties in the Relative Sunspot Numbers 被引量:16
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作者 Gui-MingLe Jia-LongWang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2003年第5期391-394,共4页
We investigate the wavelet transform of yearly mean relative sunspot number series from 1700 to 2002. The curve of the global wavelet power spectrum peaks at 11-yr, 53-yr and 101-yr periods. The evolution of the ampli... We investigate the wavelet transform of yearly mean relative sunspot number series from 1700 to 2002. The curve of the global wavelet power spectrum peaks at 11-yr, 53-yr and 101-yr periods. The evolution of the amplitudes of the three periods is studied. The results show that around 1750 and 1800, the amplitude of the 53-yr period was much higher than that of the the 11-yr period, that the ca. 53-yr period was apparent only for the interval from 1725 to 1850, and was very low after 1850, that around 1750, 1800 and 1900, the amplitude of the 101-yr period was higher than that of the 11-yr period and that, from 1940 to 2000, the 11-yr period greatly dominates over the other two periods. 展开更多
关键词 Sun: sunspots - Sun: activity - methods: data analysis
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Why are halo coronal mass ejections faster? 被引量:3
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作者 Qing-Min Zhang Yang Guo +2 位作者 Peng-Fei Chen Ming-De Ding Cheng Fang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2010年第5期461-472,共12页
Halo coronal mass ejections (CMEs) have been to be significantly faster than normal CMEs, which is a long-standing puzzle. In order to solve the puzzle, we first investigate the observed properties of 31 limb CMEs t... Halo coronal mass ejections (CMEs) have been to be significantly faster than normal CMEs, which is a long-standing puzzle. In order to solve the puzzle, we first investigate the observed properties of 31 limb CMEs that clearly display loopshaped frontal loops. The observational results show a strong tendency that slower CMEs are weaker in white-light intensity. Then, we perform a Monte Carlo simulation of 20000 artificial limb CMEs that have an average velocity of ~523km s -1. The Thomson scattering of these events is calculated when they are assumed to be observed as limb and halo events, respectively. It is found that the white-light inten-sity of many slow CMEs becomes remarkably reduced when they turn from being viewed as a limb event to being viewed as a halo event. When the intensity is below the background solar wind fluctuation, it is assumed that they would be missed by coronagraphs. The average velocity of "detectable" halo CMEs is ~922km s -1, very close to the observed value. This also indicates that wider events are more likely to be recorded. The results soundly suggest that the higher average velocity of halo CMEs is due to that a majority of slow events and some of narrow fast events carrying less material are so faint that they are blended with the solar wind fluctuations, and therefore are not observed. 展开更多
关键词 Sun: coronal mass ejections (CMEs) Sun: activity methods nu-merical solar-terrestrial relations
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Long-term variation time scales in OJ 287 被引量:1
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作者 Jun-Hui Fan Yi Liu +5 位作者 Bo-Chun Qian Jun Tao Zhi-Qiang Shen Jiang-Shui Zhang Yong Huang Jin Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2010年第11期1100-1108,共9页
The light curve data from 1894 to 2008 are compiled for the BL Lacertae object OJ 287 from the available literature. Periodicity analysis methods (the Discrete Correlation Function-DCF, the Jurkevich method, the powe... The light curve data from 1894 to 2008 are compiled for the BL Lacertae object OJ 287 from the available literature. Periodicity analysis methods (the Discrete Correlation Function-DCF, the Jurkevich method, the power spectral (Fourier) analysis, and the CLEANest method) are performed to search for possible periodicites in the light curve of OJ 287. Significance levels are given for the possible periods. The analysis results confirm the existence of the 12.2 ± 0.6 yr time scale and show a hint of a -53 yr time scale. The 12.2 ± 0.6 yr period is used as the orbital period to investigate the supermassive binary black hole system parameters. 展开更多
关键词 GALAXIES active -- galaxies: general-- methods data analysis -- galax- ies individual (OJ 287)
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Phase analysis of sunspot group numbers on both solar hemispheres 被引量:2
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作者 Lin-Hua Deng Zhong-Quan Qu +1 位作者 Xiao-Li Yan Kai-Rang Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2013年第1期104-114,共11页
Cross-correlation analysis and wavelet transform methods are proposed to investigate the phase relationship between the monthly sunspot group numbers in the solar northern and southern hemispheres. It is found that (... Cross-correlation analysis and wavelet transform methods are proposed to investigate the phase relationship between the monthly sunspot group numbers in the solar northern and southern hemispheres. It is found that (1) the monthly sunspot group numbers in the northern hemisphere begin two months earlier than those in the southern one, which should lead to phase asynchrony between them but with a slight effect; (2) the Schwabe cycle length for the monthly sunspot group numbers in the two hemispheres obviously differs from each other, and the mean Schwabe cycle length of the monthly sunspot group numbers in the northern hemisphere is slightly larger than that in the southern one; (3) the monthly sunspot group numbers in the northern hemisphere precede those in the southern hemisphere during the years of about 1874- 1927, after which, the southern hemisphere leads the northern hemisphere in the years 1928-1964, and then the northern hemisphere leads in time till the present. 展开更多
关键词 methods data analysis -- Sun activity -- Sun sunspots
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Simulation of oxygen transfer in liquid lead under influence of nanoparticles by using lattice Boltzmann method 被引量:1
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作者 Emad Pouryazdanpanah Kermani Yitung Chen 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2017年第1期22-29,共8页
Oxygen transfer presents a serious challenge in the application of liquid lead as a nuclear coolant in advanced reactors. To mitigate corrosion by liquid lead in contact with steel, carefully controlling the oxygen co... Oxygen transfer presents a serious challenge in the application of liquid lead as a nuclear coolant in advanced reactors. To mitigate corrosion by liquid lead in contact with steel, carefully controlling the oxygen concentration has been used as an effective way. Oxygen needs to mix in liquid lead uniformly and quickly. To enhance oxygen transport in liquid lead, nanoparticles are added to the liquid metal. In the current study, a lattice Boltzmann method is applied to investigate natural convection of copper/lead and aluminum oxide/lead in two-dimensional simplified container. Two thermal boundary cases are evaluated in order to check the effect of different natural convection flow patterns on oxygen transport. Some useful information are obtained such as improvement in natural convection and reduction in oxygen equilibrium time. 展开更多
关键词 Lattice Boltzmann method Oxygen transfer active oxygen control technique Nanoparticles Natural convection
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Long-term hemispheric variation of the flare index 被引量:1
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作者 Song Feng Lin-Hua Deng Shi-Chun Xu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2013年第3期343-350,共8页
The long-term hemispheric variation of the flare index is investigated. It is found that, (1) the phase difference of the flare index between the northern and southern hemispheres is about 6-7 months, which is near ... The long-term hemispheric variation of the flare index is investigated. It is found that, (1) the phase difference of the flare index between the northern and southern hemispheres is about 6-7 months, which is near the time delay between flare activity and sunspot activity; (2) both the dominant and phase-leading hemisphere of the flare index is the northern hemisphere in the considered time interval, implying that the hemispheric asynchrony of solar activity has a close connection with the N-S asymmetry of solar activity. 展开更多
关键词 Sun: activity -- Sun: flares -- methods data analysis
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Trends in gravity changes from 2009 to 2013 derived from ground-based gravimetry and GRACE data in North China 被引量:3
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作者 Shen Chongyang Xuan Songbai +1 位作者 Zou Zhengbo Wu Guiju 《Geodesy and Geodynamics》 2015年第6期423-428,共6页
North China is a key region for studying geophysical progress. In this study, ground-based and Gravity Recovery and Climate Experiment(GRACE) gravity data from 2009 to 2013 are used to calculate the gravity change r... North China is a key region for studying geophysical progress. In this study, ground-based and Gravity Recovery and Climate Experiment(GRACE) gravity data from 2009 to 2013 are used to calculate the gravity change rate(GCR) using the polynomial fitting method. In general, the study area was divided into the Shanxi rift, Jing-Jin-Ji(Beijing-Tianjin-Hebei Province), and Bohai Bay Basin(BBB) regions. Results of the distribution of the GCR determined from ground-based gravimetry show that the GCR appears to be "negativepositive-negative" from west to east, which indicates that different geophysical mechanisms are involved in the tectonic activities of these regions. However, GRACE solutions are conducted over a larger spatial scale and are able to show a difference between southern and northern areas and a mass redistribution of land water storage. 展开更多
关键词 North China Ground-based gravimetry Gravity Recovery and Climate Experiment(GRACE) Polynomial fitting method Gravity changes rate Tectonic activities Geophysical mechanisms Mass redistribution
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Periodic radio variability in NRAO 530:phase dispersion minimization analysis 被引量:1
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作者 Jun-Chao Lu Jun-Yi Wang +2 位作者 Tao An Ji-Ming Lin Hong-Bing Qiu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第6期643-650,共8页
A periodicity analysis of the radio light curves of the blazar NRAO 530 at 14.5, 8.0, and 4.8 GHz is presented employing an improved phase dispersion mini- mization technique. The result, which shows two persistent pe... A periodicity analysis of the radio light curves of the blazar NRAO 530 at 14.5, 8.0, and 4.8 GHz is presented employing an improved phase dispersion mini- mization technique. The result, which shows two persistent periodic components of 6 and ~ 10 yr at all three frequencies, is consistent with the results obtained with the Lomb-Scargle periodogram and weighted wavelet Z-transform algorithms. The reliability of the derived periodicities is confirmed by the Monte Carlo numerical sim- ulations which show a high statistical confidence. (Quasi-)Periodic fluctuations of the radio luminosity of NRAO 530 might be associated with the oscillations of the accre- tion disk triggered by hydrodynamic instabilities of the accreted flow. 展开更多
关键词 methods statistical -- galaxies: active -- galaxies: quasar: individual:NRAO 530
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The relationship between the properties of PAHs and AGN activities in type-I AGNs
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作者 Qi-Chen Feng Jing Wang +1 位作者 Hua-Li Li Jian-Yan Wei 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第5期663-672,共10页
In order to explore the relationship between properties of Polycyclic Aromatic Hydrocarbons (PAHs) and AGN activities in Type-I AGNs, we compiled a sample of 47 Type-I AGNs with measured PAH 11.3 μm and 7.7 μm emi... In order to explore the relationship between properties of Polycyclic Aromatic Hydrocarbons (PAHs) and AGN activities in Type-I AGNs, we compiled a sample of 47 Type-I AGNs with measured PAH 11.3 μm and 7.7 μm emission lines. The PAH emission and optical properties of these AGNs are taken from the literature. It is found that the equivalent width (EW) of 11.3 μm emission from PAHs shows a weak correlation with the ratio of the EWs of the FelI complex between λ4434 and A4684 to H/3 (RFe). The PAH 11.3/7.7 ratio is correlated with various elements defined by the first eigenvector space, which are RFe, [OIII]A5007 luminosity and H/3 asymmetry. These correlations infer that AGNs with high RFe, weak [OIII] emission and a strong H/3 blue-wing are likely to have low PAH ionization, and hence a larger amount of neutral PAHs. 展开更多
关键词 infrared ISM -- quasars emission lines -- galaxies active -- galaxies evolution -- methods statistical
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A new look atφ-pH diagram(Ⅰ)——All-equilibriumφ-pH diagram for M-H_(2)O system
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作者 刘海霞 张传福 曾德文 《中国有色金属学会会刊:英文版》 CSCD 2000年第6期808-812,共5页
A new viewpoint of computer program poubaix diagram was proposed on traditional φ pH diagrams. All equilibrium principle and activity term method were used to plot φ pH diagrams for M H 2O systems based on the therm... A new viewpoint of computer program poubaix diagram was proposed on traditional φ pH diagrams. All equilibrium principle and activity term method were used to plot φ pH diagrams for M H 2O systems based on the thermochemical database developed. And a new method——arithmetic geometric method is used to solve nonlinear equations group. The calculation procedure is proved to be efficient and convergent. The method seldom depends on artificial intervention and can extend to multi component all equilibrium φ pH diagrams such as M ligand H 2O system. [ 展开更多
关键词 Pourbaix diagram activity term method all-equilibrium nonlinear equation group Pb-H_(2)O system
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Overview of Industrial Materials Detection Based on Prompt Gamma Neutron Activation Analysis Technology
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作者 Jiawen Fan Jie Xu Changming Wang 《World Journal of Engineering and Technology》 2020年第3期389-404,共16页
Prompt gamma neutron activation analysis (PGNAA) is a non-destructive online measurement nuclear analysis method. With its unique advantages, it has been widely used in online analysis of industrial materials such as ... Prompt gamma neutron activation analysis (PGNAA) is a non-destructive online measurement nuclear analysis method. With its unique advantages, it has been widely used in online analysis of industrial materials such as coal, cement, and minerals in recent years. </span><span style="font-family:Verdana;">However, there are many kinds of literature on PGNAA in the field of industrial materials detection, and there are still a few concluding articles. To this end,</span><span style="font-family:Verdana;"> based on the principle of PGNAA online analysis, the status quo and development of the real-time online detection of industrial material components in the field are reviewed and discussed by consulting a large number of domestic and foreign PGNAA related literature and data, to facilitate the reference of relevant scientific researchers. 展开更多
关键词 Prompt Gamma Neutron Activation Analysis Method PGNAA On-Line Detection of Industrial Materials
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