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六朝吴歌高频用谐的发生机制
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作者 刘欣斐 张乾坤 《跨世纪》 2008年第8期123-124,共2页
以六朝时代吴歌中的谐音双关为对象,通过揭示高频用谐的发生机制,以期能为开拓民族文学现代化道路以及现代汉语语法最优化的研究工作提供一点便利。对六朝吴歌中谐音双关中的发生机制,尤其是其中的民族审美心理因素进行了深度阐明以... 以六朝时代吴歌中的谐音双关为对象,通过揭示高频用谐的发生机制,以期能为开拓民族文学现代化道路以及现代汉语语法最优化的研究工作提供一点便利。对六朝吴歌中谐音双关中的发生机制,尤其是其中的民族审美心理因素进行了深度阐明以及六朝吴歌能成为用谐修辞的巅峰之作的原因进行了独到探索。 展开更多
关键词 六朝吴歌 用谐 发生机制 高频
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Micromechanical Tunable Optical Filter 被引量:2
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作者 张瑞康 杨晓红 +7 位作者 周震 徐应强 张玮 杜云 黄永清 任晓敏 牛智川 吴荣汉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第4期347-350,共4页
A micromachined vertical cavity tunable filter with AlGaAs/GaAs distributed Bragg reflector is presented.This filter can be electrostatic tuning over a range of 28nm with an applied voltage of 7V.
关键词 micromachined tunable filter wavelength division multiplexing distributed Bragg reflector PACC:5200F 5200H 8160C
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An Improved On-Chip CMOS Astable Multivibrator 被引量:1
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作者 崔嵬 韩月秋 陈禾 《Journal of Beijing Institute of Technology》 EI CAS 2002年第4期360-363,共4页
An improved on-chip CMOS astable multivibrator is proposed, which overcomes the shortcomings of the traditional one that the signal duty-cycle is depending on model parameters, and generates stable clock signal with d... An improved on-chip CMOS astable multivibrator is proposed, which overcomes the shortcomings of the traditional one that the signal duty-cycle is depending on model parameters, and generates stable clock signal with duty-cycle equaling 50%. The latch-up effect has been prevented on the improved circuit. It is extremely important that all the excellent performances of the improved astable multivibrator have been achieved with a dynamic power consumption equaling its predecessor one. The advantage of the structure has been verified by SPICE simulation. 展开更多
关键词 CMOS ASIC astable multivibrator duty-cycle latch-up effect two divided-frequency
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Nonlinear interactions among internal tidal waves in the northeastern South China Sea 被引量:3
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作者 谢晓辉 尚晓东 陈桂英 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第5期996-1001,共6页
We used a set of 75-day long ADCP data from the northeastern South China Sea(SCS) to investigate nonlinear interactions among freely propagating internal tidal waves.The kinetic energy spectra displayed significant pe... We used a set of 75-day long ADCP data from the northeastern South China Sea(SCS) to investigate nonlinear interactions among freely propagating internal tidal waves.The kinetic energy spectra displayed significant peaks at some higher tidal frequencies,such as O1M2(O1+M2),and M4(M2 +M2),where O1 is the lunar diurnal internal tide,M2 is the lunar semidiurnal internal tide,and M4 is the first higher harmonic frequency of M2.These higher tidal harmonic frequency peaks,as well as the fundamental tidal harmonic peaks,show a σ-2.3 spectral falloff rate with frequency.In addition,we explored the possible generation mechanism of higher tidal harmonics.Analysis on the rotary and bicoherence spectra suggests that strong forced non-resonant interaction induced by nonlinear advections was the dominant physical mechanism that induced these higher tidal harmonics.Moreover,the energetic,freely propagating semidiurnal(M2) internal tidal wave played the most crucial role in these interactions.These results indicate that strong nonlinear forced non-resonant interactions among internal tides can be one of the processes responsible for the redistribution of energy in the internal wave spectrum. 展开更多
关键词 South China Sea (SCS) internal waves NONLINEARITY rotary spectra BICOHERENCE
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MZI wavelength interleaving filter based on double microring structure 被引量:1
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作者 YANG Ziwei ZHENG Yufu +2 位作者 YE Jia SHI Haoqiang WEI Xiaoming 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2021年第1期93-97,共5页
To improve the output characteristics of all-fiber Mach-Zehnder interferometer(MZI)-interleaver,a dual microring-assisted MZI interleaver is designed.According to its structure,the output expression of the device is d... To improve the output characteristics of all-fiber Mach-Zehnder interferometer(MZI)-interleaver,a dual microring-assisted MZI interleaver is designed.According to its structure,the output expression of the device is derived from the signal flow diagram.After simulation analysis,the optimal structural parameters during the transmission process are obtained.In addition,the coupling coefficient and transmission loss of the coupler are analyzed.The results show that the improved interleaver output line wave is closer to the square wave,and its 25 dB cutoff band bandwidth and 0.5 dB passband bandwidth are significantly improved,with the values of 41.2 GHz and 18.9 GHz,respectively.The device has a certain resistantability to deviation,and the transmission loss has less influence on the extinction characteristics of the filter. 展开更多
关键词 optical fiber communication Mach-Zehnder interferometer(MZI) INTERLEAVER dual microring resonator
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Silicon carbide resonant tuning fork for microsensing applications in high-temperature and high G-shock environments 被引量:6
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作者 David R Myers Kan Bun Cheng +6 位作者 Babak Jamshidi Robert G Azevedo Debbie G Senesky Li Chen Mehran Mehregany Muthu B J Wijesundara Albert P Pisano 《Engineering Sciences》 EI 2012年第5期36-41,共6页
We present the fabrication and testing of a silicon carbide (SiC) balanced mass doublended tuning fork that survives harsh environments without compromising the device strain sensitivity and resolution bandwidth. Th... We present the fabrication and testing of a silicon carbide (SiC) balanced mass doublended tuning fork that survives harsh environments without compromising the device strain sensitivity and resolution bandwidth. The device features a material stack that survives corrosive environments and enables high-temperature operation. To perform hightemperature testing, a specialized setup was constructed that allows the tuning fork to be characterized using traditional silicon electronics. The tuning fork has been operated at 600°C in the presence of dry steam for short durations. This tuning fork has also been tested to 64 000 G using a hard-launch, soft-catch shock implemented with a light gas gun. However, the device still has a strain sensitivity of 66 Hz/μe and strain resolution of 0. 045 μe in a 10 kHz bandwidth. As such, this balanced-mass double-ended tuning fork can be used to create a variety of different sensors including strain gauges, accelerometers, gyroscopes, and pressure transducers. Given the adaptable fabrication process flow, this device could be useful to micro-electro-mechanical systems (MEMS) designers creating sensors for a variety of different applications. 展开更多
关键词 MEMS SiC thermal effects double ended tuning fork (DETF) harsh environment high temperature high shock INERTIAL STRAIN sensors
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Study on the Circular Agriculture Development in Beijing's Mountain Areas
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作者 Liu Wei Dong Suocheng Jin Xianfeng 《Chinese Journal of Population,Resources and Environment》 2009年第3期55-60,共6页
Circular agriculture is an essential way to realize the positive recycling of ecology and harmonious development of the country construction.The sustainable development of Beijing's mountain areas depends on the b... Circular agriculture is an essential way to realize the positive recycling of ecology and harmonious development of the country construction.The sustainable development of Beijing's mountain areas depends on the background and orientation of ecological economy.Beijing's mountain areas bear the responsibility of protecting the ecological safety of the whole Beijing district and also the exploration of circular agriculture in mountain areas is very important to promote the sustainable use of agriculture resources.Beijing's mountain areas have possessed some practical experience in recycling agriculture development.Through summarizing the development mode and analyzing the development practice,the article puts forward three key segments of promoting Beijing circular agriculture development:strengthen propagate,develop superiority and built management mechanism. 展开更多
关键词 circular agriculture BEIJING mountain area
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Transferring of a Two-Mode Entangled State Between Two Cavities via Cavity QED
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作者 WU Tao NI Zhi-Xiang YE Liu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期451-453,共3页
We propose a scheme for transferring of a two-mode entanglement of zero- or one-photon entangled states between two cavities via atom-cavity field resonant interaction. In our proposal, in order to transfer the entang... We propose a scheme for transferring of a two-mode entanglement of zero- or one-photon entangled states between two cavities via atom-cavity field resonant interaction. In our proposal, in order to transfer the entangled state, we only need two identical two-level atoms and a two-mode cavity for receiving the teleported state. This scheme does not require Bell-state measurement and performing any transformations to reconstruct the initial state. And the transfer can occur with 100% success probability in a simple manner. And a network for transferring of a two-mode entangled state between cavities is suggested. This scheme can also be extended to transfer N-mode entangled state of cavity. 展开更多
关键词 TRANSFER cavity QED quantum entanglement resonant interaction
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Single-Photon Scattering by a Three-level System Interacting with a Whispering-Gallery Resonator Coupled to One-Dimensional Waveguide:
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作者 CHENG Mu-Tian SONG Yan-Yan LUO Ya-Qin ZHAO Guang-Xing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第3期501-505,共5页
We investigate theoretically the single-photon scattering by a A-type three-level system interacting with a whispering-gallery-type resonator which is coupled to a one-dimensional waveguide by full quantum-mechanical ... We investigate theoretically the single-photon scattering by a A-type three-level system interacting with a whispering-gallery-type resonator which is coupled to a one-dimensional waveguide by full quantum-mechanical approach. The single-photon transmission amplitude and reflection amplitude are obtained exactly via real-space approach. The single-photon transport properties controlling by classic optical field are discussed. The critical coupling condition in the coupled waveguide-whispering-gallery resonator-atom with three-level system is also analyzed. 展开更多
关键词 one-dimensional waveguide whispering gallery resonator SCATTERING single photon A-type threelevel
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A Review of Wideband Circularly Polarized Dielectric Resonator Antennas 被引量:1
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作者 Ubaid Ullah Mohd Fadzil Ain Zainal Arifin Ahmad 《China Communications》 SCIE CSCD 2017年第6期65-79,共15页
This article presents a technical review of circularly polarized(CP) dielectric resonator antennas(DRA) for wideband applications.The primary objective of this review is,to highlight the techniques used by different r... This article presents a technical review of circularly polarized(CP) dielectric resonator antennas(DRA) for wideband applications.The primary objective of this review is,to highlight the techniques used by different researchers for generating circular polarization in DRA.First,a general idea of circular polarization and it advantages over linear polarization is presented,and then all the major developments made in the CP DRA are highlighted.The emphasis of the paper is on the wideband circularly polarized dielectric resonator antenna.The current state of the art and all the realizable features of the CP DRA are addressed comprehensively.Finally,some recommendations for future CP DRAs are given and the paper ends with concluding remarks. 展开更多
关键词 circularly polarized dielectric resonator antenna dielectric resonator antenna circular polarization techniques
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Development of capacitive sensor signal conditioning system for angular displacement measurement using timer IC LM555 and UFDC 被引量:2
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作者 Sumitesh Majumder T K Maiti 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2019年第1期49-54,共6页
In this research paper,we have presented variable area type capacitive sensor signal conditioning system for angular displacement measurement and for this purpose we have used timer LM555 based astable multivibrator a... In this research paper,we have presented variable area type capacitive sensor signal conditioning system for angular displacement measurement and for this purpose we have used timer LM555 based astable multivibrator and universal frequency to digital converter (UFDC). Due to variation in angular displacement in the variable area type capacitor which is connected in the timer based astable circuit,capacitance changes which in turn changes the time period of the timer circuit output. The time period of the timer output waveform is linear with the capacitance and hence linear with angular displacement. The timer output is further processed with UFDC for the measurement. The experimental results show that the time period is linear with the angular displacement in the range of 0- 180° and the uncertainty we should associate it with this average time period value is the standard deviation of the mean,often called the standard error (SE),which is ± 0.023 μs. Because of the simplicity,this measurement system can be used in both electronic and industrial instrumentation. 展开更多
关键词 variable area type capacitive sensor timer circuit sensor interfacing astable multivibrator universal frequency to digital converter (UFDC)
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Generation of W-Type Entangled Coherent States of Three-Cavity Fields by a Driving Classical Field
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作者 CHEN Mei-Feng JIANG Xia-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2X期303-305,共3页
A scheme is proposed to generate the W-type entangled coherent states of three-cavity field. The scheme is based on the resonant atom-field interaction, thus the interaction time between the atom and the cavity is gre... A scheme is proposed to generate the W-type entangled coherent states of three-cavity field. The scheme is based on the resonant atom-field interaction, thus the interaction time between the atom and the cavity is greatly reduced, which is important in view of decoherence. Furthermore, the scheme does not need accurate adjustment of the interaction time. 展开更多
关键词 resonant interaction driving classical field W-type entangled coherent states
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Speed Geometric Quantum Logical Gate Based on Double-Hamiltonian Evolution under Large-Detuning Cavity QED Model
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作者 陈昌永 刘宗良 +1 位作者 康帅 李韶华 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期672-674,共3页
We introduce the double-Hamiltonian evolution technique approach to investigate the unconventional geometric quantum logical gate with dissipation under the model of many identical three-level atoms in a cavity~ drive... We introduce the double-Hamiltonian evolution technique approach to investigate the unconventional geometric quantum logical gate with dissipation under the model of many identical three-level atoms in a cavity~ driven by a classical fieM. Our concrete calculation is made for the case of two atoms for the large-detuning interaction of the atoms with the cavity mode. The main advantage of our scheme is of eliminating the photon flutuation in the cavity mode during the gating. The corresponding analytical results will be helpful for experimental realization of speed geometric quantum logical gate in real cavities. 展开更多
关键词 unconventional geometric gate dissipation the heating effect
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Third-order active-RC complex filter with automatic frequency tuning for ZigBee transceiver applications 被引量:6
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作者 李迪 井站 +3 位作者 杨银堂 吴笑峰 石佐辰 柳杨 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期966-973,共8页
A 3rd-order Butterworth active-RC complex band-pass filter was presented for Zig Bee(IEEE802.15.4) transceiver applications. The filter adopted cascaded complex pole stages to realize the 3 MHz bandwidth with a centre... A 3rd-order Butterworth active-RC complex band-pass filter was presented for Zig Bee(IEEE802.15.4) transceiver applications. The filter adopted cascaded complex pole stages to realize the 3 MHz bandwidth with a centre frequency of 2 MHz which was required by the Zig Bee transceiver applications. An automatic frequency tuning scheme was also designed to accommodate the performance deterioration due to the process, voltage and temperature(PVT) variations. The whole filter is implemented in a 0.18 μm standard process and occupies an area of 1.3 mm×0.6 mm. The current dissipation is 1.2 m A from a 1.8 V single power supply. Measurement results show that the image rejection ratio(IRR) of the filter is 24.1 d B with a pass-band ripple less than 0.3 d B. The adjacent channel rejection is 29.8 d B@7 MHz and alternate channel rejection 47.5 d B@12 MHz, respectively. 展开更多
关键词 active-RC complex filter Zig Bee frequency tuning channel rejection
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Quantum Anti-Zeno Effect in Artificial Quantum Systems 被引量:1
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作者 艾清 廖洁桥 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第12期985-996,共12页
In this paper, we study a quantum anti-Zeno effect (QAZE) purely induced by repetitive measurements for an artificial atom interacting with a structured bath. This bath can be artificially realized with coupled reso... In this paper, we study a quantum anti-Zeno effect (QAZE) purely induced by repetitive measurements for an artificial atom interacting with a structured bath. This bath can be artificially realized with coupled resonators in one dimension and possesses photonic band structure like Bloeh electron in a periodic potential. In the presence of repetitive measurements, the pure QAZE is discovered as the observable decay is not negligible even for the atomic energy level spacing outside of the energy band of the artificial bath. If there were no measurements, the decay would not happen outside of the band. In this sense, the enhanced decay is completely induced by measurements through the relaxation channels provided by the bath. Besides, we also discuss the controversial golden rule decay rates originated from the van Hove's singularities and the effects of the counter-rotating terms. 展开更多
关键词 quantum Zeno effect quantum anti-Zeno effect artificial quantum system
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FPGA Resources Reduction by a Multiplexing Technique Applied on ANN-Based Harmonics Extraction Algorithms
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作者 Serge Raoul Dzonde Naoussi Ngac-Ky Nguyen +4 位作者 Charles-Hubert Kom Herve Berviller Jean-Philippe Blonde Martin Kom Francis Braun 《Journal of Energy and Power Engineering》 2012年第3期469-477,共9页
In this paper, a multiplexing technique is applied on a neural harmonics extraction method, based on an efficient formulation of the instantaneous reactive power theory. This approach can be used in nonlinear loads co... In this paper, a multiplexing technique is applied on a neural harmonics extraction method, based on an efficient formulation of the instantaneous reactive power theory. This approach can be used in nonlinear loads compensation with APFs (Active Power Filters). The architecture for reference current generation, synchronized by a neural phase lock-loop, is composed of three Adaline neural networks. This leads to an important consumption of field programmable gate array resources during implementation. The proposed technique uses only one Adaline and keeps the immunity of the approach under non-sinusoidal and unbalanced conditions of voltage. Simulation results of the neural harmonics detection system connected to a reference current controller show balanced and sinusoidal source currents under various conditions. Results with experimental measurement made on an APF test bench demonstrate its good performances on harmonics filtering. Moreover, the simplified structure from the new approach called mp-q method shows a significant resource reduction. 展开更多
关键词 FPGA active power filters instantaneous reactive power theory power quality resource reduction.
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Weak Orlicz spaces:Some basic properties and their applications to harmonic analysis 被引量:8
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作者 LIU PeiDe WANG MaoFa 《Science China Mathematics》 SCIE 2013年第4期789-802,共14页
We study some basic properties of weak Orlicz spaces and their applications to harmonic analysis.We first discuss the absolute continuity of the quasi-norm and its normality,then prove the boundedness of several maxim... We study some basic properties of weak Orlicz spaces and their applications to harmonic analysis.We first discuss the absolute continuity of the quasi-norm and its normality,then prove the boundedness of several maximal operators.We also establish a kind of Marcinkiewicz-type interpolation theorem between weak Orlicz spaces.As applications,the weak type analogues of several classical inequalities in harmonic analysis is obtained. 展开更多
关键词 weak Orlicz space NORMALITY maximal operator interpolation theorem singular integral operator
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Tunable Q-factor wavelet transform denoising with neighboring coefficients and its application to rotating machinery fault diagnosis 被引量:27
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作者 HE WangPeng ZI YanYang +2 位作者 CHEN BinQiang WANG Shuai HE ZhengJia 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第8期1956-1965,共10页
Fault diagnosis of rotating machinery is of great importance to the high quality products and long-term safe operation.However,the useful weak features are usually corrupted by strong background noise,thus increasing ... Fault diagnosis of rotating machinery is of great importance to the high quality products and long-term safe operation.However,the useful weak features are usually corrupted by strong background noise,thus increasing the difficulty of the feature extraction.Thereby,a novel denoising method based on the tunable Q-factor wavelet transform(TQWT)using neighboring coefficients is proposed in this article.The emerging TQWT possesses excellent properties compared with the conventional constant-Q wavelet transforms,which can tune Q-factor according to the oscillatory behavior of the signal.Meanwhile,neighboring coefficients denoising is adopted to avoid the overkill of conventional term-by-term thresholding techniques.Because of having the combined advantages of the two methods,the presented denoising method is more practical and effective than other methods.The proposed method is applied to a simulated signal,a rolling element bearing with an outer race defect from antenna transmission chain and a gearbox fault detection case.The processing results demonstrate that the proposed method can successfully identify the fault features,showing that this method is more effective than the conventional wavelet thresholding denoising methods,term-by-term TQWT denoising schemes and spectral kurtosis. 展开更多
关键词 tunable Q-factor wavelet transform(TQWT) signal denoising neighboring coefficients fault diagnosis
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Tuning the solid-state emission of the analogous GFP chromophore by varying alkyl chains in the imidazolinone ring
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作者 SHEN Xiang HUANG GuangXi +2 位作者 LI Kan ZHANG GuanXin ZHANG DeQing 《Science China Chemistry》 SCIE EI CAS 2013年第9期1197-1203,共7页
New analogues of green fluorescent protein (GFP) chromophore mGFP-Cn (n = 1, 3, 5, 11) with alkyl chains of different lengths in the imidazolinone rings were synthesized and their crystal structures were determined. T... New analogues of green fluorescent protein (GFP) chromophore mGFP-Cn (n = 1, 3, 5, 11) with alkyl chains of different lengths in the imidazolinone rings were synthesized and their crystal structures were determined. These GFP-like chromophores are all emissive in the solid state. And the solid-state emission quantum yields of increase by extending the lengths of alkyl chains, owing to the fact that the intermolecular pi-pi interactions are significantly weakened based on their crystal structures. 展开更多
关键词 green fluorescent protein (GFP) chromorphore solid-state fluorescence fluorescence modulation
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Quantum discord in three-spin XXZ chain with three-spin interaction 被引量:2
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作者 YUE HaiDi ZHANG Yong GONG Jian 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第9期1641-1645,共5页
Quantum discord, as a kind of measurement of quantum correlation, has received much attention since it was introduced. This paper focuses on studying quantum discord in three-spin XXZ chain with three-spin interaction... Quantum discord, as a kind of measurement of quantum correlation, has received much attention since it was introduced. This paper focuses on studying quantum discord in three-spin XXZ chain with three-spin interaction. The effects of all kinds of pa- rameters on quantum discord in the ferromagnetic region J=-I are studied. The three-spin interaction may increase the value of quantum discord between two spins, while the anisotropy may decrease the value. In addition, the regrowth of quantum discord with temperature is found in the model. For zero temperature, quantum phase transition is existent. 展开更多
关键词 quantum discord three-spin interaction XXZ-spin chain
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