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萧何迁相时间考述
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作者 苗苗 《新乡学院学报》 2023年第11期50-52,共3页
萧何为西汉政权的建立和巩固做出了重大贡献,刘邦称帝后,封萧何为相国。《史记》《汉书》《资治通鉴》等典籍对萧何的事迹均有记载,然而,它们对萧何迁相时间的记述却不一致。考之诸典籍,分析现有研究成果,萧何迁相极有可能是在汉高祖十... 萧何为西汉政权的建立和巩固做出了重大贡献,刘邦称帝后,封萧何为相国。《史记》《汉书》《资治通鉴》等典籍对萧何的事迹均有记载,然而,它们对萧何迁相时间的记述却不一致。考之诸典籍,分析现有研究成果,萧何迁相极有可能是在汉高祖十一年正月,也就是刘邦平定陈豨之乱回到汉中之后。 展开更多
关键词 萧何 迁相 汉高祖十一年
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Phase field calculation of interface mobility in a ternary alloy 被引量:1
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作者 王刚 曾德长 刘仲武 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第7期1711-1716,共6页
A novel approach based on the quantitative phase field model was proposed to calculate the interface mobility and applied to the α/β interface of a ternary Ti-6Al-4V alloy.Phase field simulations indicate that the h... A novel approach based on the quantitative phase field model was proposed to calculate the interface mobility and applied to the α/β interface of a ternary Ti-6Al-4V alloy.Phase field simulations indicate that the higher interface mobility leads to the faster transformation rate,but only a unique value of interface mobility matches the diffusion equation under the diffusion-controlled condition.By comparing the transformation kinetics from phase field simulations with that from classical diffusion equation,the interface mobility at different temperatures can be obtained.The results show that the calculated interface mobility increases with increasing temperature and accords with Arrhenius equation very well. 展开更多
关键词 phase transformation DIFFUSION phase field modeling interface mobility
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Study on Deliver Analysis Method of Heavy Metal Elements during Cigarette Smoking
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作者 李登科 范国樑 +4 位作者 范学忠 张春涛 李莉霞 马立超 邢立霞 《Agricultural Science & Technology》 CAS 2016年第11期2642-2646,2660,共6页
[Objective] The deliver amount and deliver rate of heavy metal elements during smoking were studied, which could provide a reference for reducing the damage of cigarette products. [Method] Two pretreatment methodsof m... [Objective] The deliver amount and deliver rate of heavy metal elements during smoking were studied, which could provide a reference for reducing the damage of cigarette products. [Method] Two pretreatment methodsof microwave di- gestion and acid extraction were used to process the ash content, the total particu- late matter of mainstream smoke (TPM) and cigarette filter. Detection results of heavy metal elements were compared by the two methods. [Result] The microwave digestion method was better than acid solution extraction method on analysis of TPM, but presented disadvantages on analysis of ash and filter. Meanwhile, the migration amount and rate were studied and resultsshowed that most heavy metal elements were escaped along with sidestream smoke between 66.89% and 95.48%, and almost all Hg escaped through sidestream smoke. Other heavy metal elements, except Hg, were separately found in ash, TPM and filter. Cr, Ni, As and Se were mostly residual in ash, followed by TPM, and filter had the least, while Cd and Pb were just in the reverse order. Normally, 5% or less heavy metal elements were transferred to TPM, only a small part of which could reach 5%-10%. [Conclusion] Most of the heavy metal elements are taken by sidestream smoke, ash and filter, while the migration amounts to mainstream smoke are extremely low. 展开更多
关键词 CIGARETTE Heavy metal Migration rate Total particulate matter (TPM) ASH
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Energies and Transition Rates of Low-Lying Excited States for Beryllium
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作者 韩利红 苟秉聪 王菲 《Journal of Beijing Institute of Technology》 EI CAS 2002年第1期109-112,共4页
Low lying excited states of beryllium are calculated with multiconfiguration interaction method. The relativisitic corrections and mass polarization are included. The oscillator strength and radiation rates are also ... Low lying excited states of beryllium are calculated with multiconfiguration interaction method. The relativisitic corrections and mass polarization are included. The oscillator strength and radiation rates are also calculated. Our results are in good agreement with other theoretical data. 展开更多
关键词 oscillator strength radiation transition BERYLLIUM
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Primary and secondary modes of deformation twinning in HCP Mg based on atomistic simulations 被引量:3
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作者 徐泓鹭 苏小明 +1 位作者 袁广银 金朝晖 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期3804-3809,共6页
Deformation twinning, i.e., twin nucleation and twin growth (or twin boundary migration, TBM) activated by impinged basal slip at a symmetrical tilt grain boundary in HCP Mg, was examined with molecular dynamics (M... Deformation twinning, i.e., twin nucleation and twin growth (or twin boundary migration, TBM) activated by impinged basal slip at a symmetrical tilt grain boundary in HCP Mg, was examined with molecular dynamics (MD) simulations. The results show that the {1^-1^-21}-type twinning acts as the most preferential mode of twinning. Once such twins are formed, they are almost ready to grow. The TBM of such twins is led by pure atomic shuffling events. A secondary mode of twinning can also occur in our simulations. The {112^-2} twinning is observed at 10 K as the secondary twin. This secondary mode of twinning shows different energy barriers for nucleation as well as for growth compared with the {1^-1^-21}-type twining. In particular, TBMs in this case is triggered intrinsically by pyramidal slip at its twin boundary. 展开更多
关键词 MAGNESIUM atomistic simulation deformation twinning twin boundary migration dislocation-grain boundary interaction
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Transitions in a Logistic Growth Model Induced by Noise Coupling and Noise Color 被引量:2
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作者 SHI Jin ZHU Shi-Qun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1X期175-182,共8页
With unified colored noise approximation, the logistic growth model is used to analyze cancer cell population when colored noise is included. It is found that both the coupling between noise terms and the noise color... With unified colored noise approximation, the logistic growth model is used to analyze cancer cell population when colored noise is included. It is found that both the coupling between noise terms and the noise color can induce continuous first-order-like and re-entrance-like phase transitions in the system. The coupling and the noise color can also increase tumor cell growth for small number of cell mass and repress tumor cell growth for large number of cell mass. It is shown that the approximate analytic expressions are consistent with the numerical simulations. 展开更多
关键词 logistic growth model first-order-like phase transition re-entrance-like phase transition colored noise
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Relationship between oxygen species and activity/stability in heteroatom(Zr,Y)-doped cerium-based catalysts for catalytic decomposition of CH_3SH 被引量:4
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作者 Dingkai Chen Dehua Zhang +4 位作者 Dedong He Jichang Lu Liping Zhong Caiyun Han Yongming Luo 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第12期1929-1941,共13页
CeO2,Ce1–xZrxO2,and Ce1–xYxO2–δ(x=0.25,0.50,0.75,and 1.00)have been rapidly synthesized to estimate their catalytic behavior in decomposing CH3SH.The role of oxygen vacancies,and the relationship between the oxyge... CeO2,Ce1–xZrxO2,and Ce1–xYxO2–δ(x=0.25,0.50,0.75,and 1.00)have been rapidly synthesized to estimate their catalytic behavior in decomposing CH3SH.The role of oxygen vacancies,and the relationship between the oxygen species and catalytic properties of CeO2 and Zr‐doped and Y‐doped ceria‐based materials are investigated in detail.Combining the observed catalytic performance with the characterization results,it can be deemed that surface lattice oxygen plays a critical role in methanethiol catalytic conversion over cerium oxides.Ce0.75Zr0.25O2 shows higher catalytic activity for CH3SH decomposition due to the large amount of surface lattice oxygen,readily available oxygen species,and excellent redox properties.Ce0.75Y0.25O2–δdisplays better catalytic stability owing to the greater number of oxygen vacancies that would promote bulk lattice oxygen migration to the surface of the catalyst in order to replenish surface lattice oxygen.In addition,the results show that the difference in chemical valence between Ce and the heteroatoms would strongly influence the amount of surface lattice oxygen as well as the mobility of bulk‐phase oxygen in these catalysts,thus affecting their activity and stability. 展开更多
关键词 Cerium‐base catalyst HETEROATOM Surface lattice oxygen CH3SH decomposition Bulk oxygen migration
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Energy Spectrum of Two-Component Bose-Einstein Condensates in Optical Lattices 被引量:1
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作者 HANJiu-Rong LIUJin-Ming +1 位作者 JINGHui WANGYu-Zhu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期809-813,共5页
With the method of Green's function, we investigate the energy spectra of two-component ultracold bosonic atoms in optical lattices. We End that there are two energy bands for each component. The critical conditio... With the method of Green's function, we investigate the energy spectra of two-component ultracold bosonic atoms in optical lattices. We End that there are two energy bands for each component. The critical condition of the superfluid-Mott insulator phase transition is determined by the energy band structure. We also find that the nearest neighboring and on-site interactions fail to change the structure of energy bands, but shift the energy bands only. According to the conditions of the phase transitions, three stable superfluid and Mott insulating phases can be found by adjusting the experiment parameters. We also discuss the possibility of observing these new phases and their transitions in further experiments. 展开更多
关键词 energy spectrum phase transition Bose-Einstein condensates optical lattice
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Symmetry Breaking Ground States of Bose-Einstein Condensates in 1D Double Square Well and Optical Lattice Well 被引量:1
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作者 YUANQing-Xin DINGGuo-Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期814-818,共5页
We investigate the phenomena of symmetry breaking and phase transition in theground state of Bose-Einstein condensates (BECs) trapped in a double square well and in an opticallattice well, respectively. By using stand... We investigate the phenomena of symmetry breaking and phase transition in theground state of Bose-Einstein condensates (BECs) trapped in a double square well and in an opticallattice well, respectively. By using standing-wave expansion method, we present symmetric andasymmetric ground state solutions of nonlinear Schroedinger equation (NLSE) with a symmetric doublesquare well potential for attractive nonlinearity. In particular, we study the ground state wavefunction's properties by changing the depth of potential and atomic interactions (here we restrictourselves to the attractive regime). By using the Fourier grid Hamiltonian method, we also reveal aphase transition of BECs trapped in one-dimensional optical lattice potential. 展开更多
关键词 Bose-Einstein condensates symmetry breaking state phase transition
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Domain adaptive methods for device diversity in indoor localization 被引量:1
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作者 Liu Jing Liu Nan +1 位作者 Pan Zhiwen You Xiaohu 《Journal of Southeast University(English Edition)》 EI CAS 2019年第4期424-430,共7页
To solve the problem of variations in radio frequency characteristics among different devices,transfer learning is applied to transform device diversity to domain adaptation in the indoor localization algorithm.A robu... To solve the problem of variations in radio frequency characteristics among different devices,transfer learning is applied to transform device diversity to domain adaptation in the indoor localization algorithm.A robust indoor localization algorithm based on the aligned fingerprints and ensemble learning called correlation alignment for localization(CALoc)is proposed with low computational complexity.The second-order statistical properties of fingerprints in the offline and online phase are needed to be aligned.The real-time online calibration method mitigates the impact of device heterogeneity largely.Without any time-consuming deep learning retraining process,CALoc online only needs 0.11 s.The effectiveness and efficiency of CALoc are verified by realistic experiments.The results show that compared to the traditional algorithms,a significant performance gain is achieved and that it achieves better positioning accuracy with a 19%improvement. 展开更多
关键词 wireless local area networks indoor localization fingerprinting device diversity transfer learning correlation alignment
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Superfluidity of Paired Bosons from Correlated Tunneling
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作者 YANG Shi-Jie 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第10期611-614,共4页
We study superfluidity of paired Bosonic atoms in optical lattices. The atoms have strong repulsive on-slte energy. Single atom tunneling is severely suppressed while the atom-pair may co-tunnel by the second order qu... We study superfluidity of paired Bosonic atoms in optical lattices. The atoms have strong repulsive on-slte energy. Single atom tunneling is severely suppressed while the atom-pair may co-tunnel by the second order quantum transition, which induces paired superfluidity as repulsive nearest-neighbor interactions are included. The mean-field phase diagram and low energy excitations are explored for a square lattice system. 展开更多
关键词 SUPERFLUIDITY correlated tunneling PAIRING
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A 0.6 μm CMOS bandgap voltage reference circuit
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作者 梁帮立 王志功 +5 位作者 田俊 冯军 夏春晓 胡艳 张丽 熊明珍 《Journal of Southeast University(English Edition)》 EI CAS 2003年第3期221-224,共4页
On the basis of mutual compensation of mobility and threshold voltage temperature effects, a stable CMOS band-gap voltage reference circuit was designed and fabricated in CSMC-HJ 0.6 μm CMOS technology. Operating fro... On the basis of mutual compensation of mobility and threshold voltage temperature effects, a stable CMOS band-gap voltage reference circuit was designed and fabricated in CSMC-HJ 0.6 μm CMOS technology. Operating from 0 to 85 ℃ under a supply voltage ranging from 4.5 to 5.5 V, the voltage reference circuit offers an output reference voltage ranging from 1.122 to 1.176 V and a voltage variation less than ±3.70%. The chip size including bonding pads is only 0.4 mm×0.4 mm and the power dissipation falls inside the scope of 28.3 to 48.8 mW operating at a supply voltage of 4.5 to 5.5 V. 展开更多
关键词 CMOS mutual compensation mobility and threshold voltage temperature effects
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Phase Field Simulation of Intragranular Microvoids Evolution Due to Surface Diffusion in Stress Field 被引量:1
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作者 ZHOU Linyong HUANG Peizhen ZHANG Jiaming 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第3期280-290,共11页
Based on the bulk free energy density and the degenerate mobility constructed by the quartic double-well potential function,a phase field model is established to simulate the evolution of intragranular microvoids due ... Based on the bulk free energy density and the degenerate mobility constructed by the quartic double-well potential function,a phase field model is established to simulate the evolution of intragranular microvoids due to surface diffusion in a stress field.The corresponding phase field governing equations are derived.The evolution of elliptical microvoids with different stressesΛ,aspect ratiosβand linewidths hˉis calculated using the mesh adaptation finite element method and the reliability of the procedure is verified.The results show that there exist critical values of the stressΛc,the aspect ratioβc and the linewidth hˉc of intragranular microvoids under equivalent biaxial tensile stress.When Λ≥Λ_(c),β≥β_(c) or h≤h_(c),the elliptical microvoids are instable with an extending crack tip.WhenΛ<Λ_(c),β<β_(c) or hˉ>h_(c),the elliptical microvoids gradually cylindricalize and remain a stable shape.The instability time decreases with increasing the stress or the aspect ratio,while increases with increasing the linewidth.In addition,for the interconnects containing two elliptical voids not far apart,the stress will promote the merging of the voids. 展开更多
关键词 phase field method stress migration surface diffusion finite element method intragranular microvoid
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Ising Model on an Infinite Ladder Lattice
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作者 GAO Xing-Ru 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期553-562,共10页
In this paper we propose an Ising model on an infinite ladder lattice, which is made of two infinite Ising spin chains with interactions. It is essentially a quasi-one-dimessional Ising model because the length of the... In this paper we propose an Ising model on an infinite ladder lattice, which is made of two infinite Ising spin chains with interactions. It is essentially a quasi-one-dimessional Ising model because the length of the ladder lattice is infinite, while its width is finite. We investigate the phase transition and dynamic behavior of Ising model on this quasi-one-dimessional system. We use the generalized transfer matrix method to investigate the phase transition of the system. It is found that there is no nonzero temperature phase transition in this system. At the same time, we are interested in Glauber dynamics. Based on that, we obtain the time evolution of the local spin magnetization by exactly solving a set of master equations. 展开更多
关键词 Ising model general transfer matrix phase transition Glauber dynamics critical slow down
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Quantum Phase Transition in Two Species of Cold Bosonic Atoms
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作者 YU Zhao-Xian LIANG Jiu-Qing +1 位作者 JIAO Zhi-Yong WANG Ji-Suo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期467-470,共4页
In this letter, the superfluid-Mott-insulator phase transition of two-species cold bosonic atoms in an optical lattices is studied. The Hamiltonian of this model is diagonalized by means of Bogliubov transformations a... In this letter, the superfluid-Mott-insulator phase transition of two-species cold bosonic atoms in an optical lattices is studied. The Hamiltonian of this model is diagonalized by means of Bogliubov transformations and by the inversion symmetry of the optical lattice, the energy spectrum of this system is obtained. From She energy gap of the excitation spectrum, the quantum phase transition condition is obtained and it is determined by the competition between the interatomic repulsions and the tunnel coupling. It is found that there exists an ordinary fluid phase when taking the zero wave-vector limit. 展开更多
关键词 Bose-Einstein condensate phase transition
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Carrier Transport Properties in the Doped Micro - crystalline Silicon Films
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作者 ZHONG Bo-qiang (Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 ,CHN) 《Semiconductor Photonics and Technology》 CAS 1999年第3期186-189,共4页
Doped micro-crystalline silicon films are deposited at temperatures as low as 400 ℃ by the catalytic chemical vapor deposition method using a silane and hydrogen gas mixture. Electrical properties such as the carrier... Doped micro-crystalline silicon films are deposited at temperatures as low as 400 ℃ by the catalytic chemical vapor deposition method using a silane and hydrogen gas mixture. Electrical properties such as the carrier concentration and the Hall mobility are investigated for various measuring temperatures. It is found that the grains of micro-crystalline silicon are preferentially oriented along the (220) direction , and that the Hall mobility is larger than 8 cm 2·V -1 ·s -1 , the carrier concentration is about 1×10 17 cm -1 ~1×10 19 cm -3 at room temperature. 展开更多
关键词 Catalytic Chemical Vapor Deposition Hall Mobility Micro-crystalline Silicon CLC number:TN201 O431 Document code:A
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Identification of the Interaction between P-Glycoprotein and Anxa2 in Multidrug-resistant Human Breast Cancer Cells 被引量:6
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作者 Hai-chang Zhang Fei Zhang +4 位作者 Bing Wu Jing-hua Han Wei Ji Yan Zhou Rui-fang Niu 《Clinical oncology and cancer researeh》 CAS CSCD 2012年第2期99-104,共6页
Objective To explore the interaction of Anxa2 with P-Glycoprotein (P-gp) in the migration and invasion of the multidrug-resistant (MDR) human breast cancer cell line MCF-7/ADR. Methods A pair of short hairpin RNA ... Objective To explore the interaction of Anxa2 with P-Glycoprotein (P-gp) in the migration and invasion of the multidrug-resistant (MDR) human breast cancer cell line MCF-7/ADR. Methods A pair of short hairpin RNA (shRNA) targeting P-gp was transfected into MCF-7/ADR cells, and monoclonal cell strains were screened. The expression of P-gp was detected by Western blot. Transwell chambers were used to observe the cell migration capacity and invasion ability. The interaction between P-gp and Anxa2 was examined by immunoprecipitation and immunofluorescence confocal microscopy analyses. Results P-gp expression was significantly knocked down, and there were notable decreasing trends in the migration and invasion capability of MDR breast cancer cells (P〈0.05). There was a close interaction between Anxa2 and P-gp. Conclusions MCF-7/ADR is an MDR human breast cancer cell line with high migration and invasion abilities. The knockdown of P-gp notably impaired the migration and invasion abilities of the tumor cells. The interaction of Anxa2 with P-pg may play an important role in time enhanced invasiveness of MDR human breast cancer cells. 展开更多
关键词 P-GLYCOPROTEIN Anxa2 drug resistance MULTIPLE neoplasm metastasis breast neoplasm
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A Study on the Changes of Medical Insurance Operation Mechanism in China
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作者 HUANG Tingting WANG Shu 《International English Education Research》 2017年第2期39-41,共3页
The operating mechanism refers to the structural setup, component assembly and inspection maintenance of the safeguards and its efficient operation. Health insurance management mechanism refers to the effective combin... The operating mechanism refers to the structural setup, component assembly and inspection maintenance of the safeguards and its efficient operation. Health insurance management mechanism refers to the effective combination, governance, operation, evaluation and improvement of medical service stakeholders. It is a series of institutional arrangements to effectively provide medical services and safeguard the interests of beneficiaries." 展开更多
关键词 Health care GOVERNANCE Operation Mechanism TRANSFORMATION
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Low phase noise millimeter wave monolithic integrated phase locked-loop
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作者 Tang Lu Wang Zhigong Qiu Yinghua Xu Jian 《High Technology Letters》 EI CAS 2012年第3期263-266,共4页
A Monolithic integrated phase locked-loop (PLL) with a low phase noise is proposed in this paper. Several techniques are utilized to improve the performance of the PLL which works at the milli- meter-wave band. The ... A Monolithic integrated phase locked-loop (PLL) with a low phase noise is proposed in this paper. Several techniques are utilized to improve the performance of the PLL which works at the milli- meter-wave band. The on-chip high-Q eoplanar waveguides (CPWs) are utilized in the resonant tank and the differential current amplifier with a resonator is used to realize the VCO. In the output buffer circuit, several stages of cascaded source-followers connect and differential amplifiers are adopted to improve the driving capability of the PLL' s output signals. An improved analog multiplier topology is also used in the PD circuit to improve the gain of the PD. The proposed PLL is realized with a 0.2p, m GaAs pseudomorphie high electron mobility transistor (PHEMT) process. At 10 kHz offset from the center frequency, the measured output phase noise of the PLL output is only -88.83dBc/Hz. The circuit exhibits a low root mean sauare (RMS) litter of 1.68Ds. 展开更多
关键词 phase locked loop (PLL) voltage-controlled oscillator (VCO) coplanarwaveguides (CPWs) GAAS
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The Research of Laminar-Turbulent Transition in Hypersonic Three-Dimensional Boundary Layer 被引量:1
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作者 Marat A.GOLDFELD Evgeniy V.ORLIK 《Journal of Thermal Science》 SCIE EI CAS CSCD 2005年第2期103-107,共5页
The results of experimental investigation of laminar-turbulent transition in three-dimensional flow under the high continuous pressure gradient including the flow with local boundary layer separation are presented. Th... The results of experimental investigation of laminar-turbulent transition in three-dimensional flow under the high continuous pressure gradient including the flow with local boundary layer separation are presented. The experimental studies were performed within the Mach number range from 4 to 6 and Reynolds number 10-60×106 1/m, the angles of attack were 0° and 5°. The experiments were carried out on the three-dimensional convergent inlet model with and without sidewalls. The influence of artificial tubulator of boundary layer on transition and flow structure was studied. The conducted researches have shown that adverse pressure gradient increase hastens transition and leads to decrease of transition area length. If pressure gradient rises velocity profile fullness increases and profile transformation from laminar to turbulent occurs. As a result of it the decrease of separation area length occurs. The same effect was reached with Reynolds number increase. These results are compared with the data on two-dimensional model with longitudinal curvature. 展开更多
关键词 hypersonic boundary layer TRANSITION convergent inlet adverse pressure gradient.
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