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Dynamic light storage based on controllable electromagnetically induced transparency effect
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作者 曾柳莹 吴俊芳 李潮 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期298-304,共7页
We analytically and numerically investigate a signal light storing mechanism based on the controllable electromagnetically induced transparency(EIT)effect.We demonstrate that the isolation between the waveguide and th... We analytically and numerically investigate a signal light storing mechanism based on the controllable electromagnetically induced transparency(EIT)effect.We demonstrate that the isolation between the waveguide and the cavities cannot be achieved instantly as soon as the two cavities are tuned into resonance,no matter the index tuning rate is ultrafast or slow.We also investigate the temporal evolution features of the intracavity energy when the pulse during time is prolonged.We find many periodical oscillations of the trapped energy in both cavities,and they are entirely complementary.Our analysis shows that the adiabatic wavelength conversion in both cavities and a phase difference π between them play critical roles in this phenomenon. 展开更多
关键词 dynamic light storage electromagnetically induced transparency dynamic modulation photonic crystal
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Obtaining 2D Soil Resistance Profiles from the Integration of Electrical Resistivity Data and Standard Penetration Test (SPT) and Light Dynamic Penetrometer (DPL) Resistance Tests—Applications in Mass Movements Studies
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作者 Cassiano Antonio Bortolozo Tatiana Sussel Gonçalves Mendes +10 位作者 Mariana Ferreira Benessiuti Motta Silvio Jorge Coelho Simões Tristan Pryer Daniel Metodiev Marcio Roberto Magalhães de Andrade Maiconn Vinicius de Moraes Danielle Silva de Paula Nélio José Bastos Luana Albertani Pampuch Rodolfo Moreda Mendes Marcio Augusto Ernesto de Moraes 《International Journal of Geosciences》 2023年第9期840-854,共15页
In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occ... In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occurrences. The multifaceted nature of these influences makes the surveillance of mass movements a highly intricate task, requiring an understanding of numerous interdependent variables. Recent years have seen an emergence in scholarly research aimed at integrating geophysical and geotechnical methodologies. The conjoint examination of geophysical and geotechnical data offers an enhanced perspective into subsurface structures. Within this work, a methodology is proposed for the synchronous analysis of electrical resistivity geophysical data and geotechnical data, specifically those extracted from the Light Dynamic Penetrometer (DPL) and Standard Penetration Test (SPT). This study involved a linear fitting process to correlate resistivity with N10/SPT N-values from DPL/SPT soundings, culminating in a 2D profile of N10/SPT N-values predicated on electrical profiles. The findings of this research furnish invaluable insights into slope stability by allowing for a two-dimensional representation of penetration resistance properties. Through the synthesis of geophysical and geotechnical data, this project aims to augment the comprehension of subsurface conditions, with potential implications for refining landslide risk evaluations. This endeavor offers insight into the formulation of more effective and precise slope management protocols and disaster prevention strategies. 展开更多
关键词 GEOPHYSICS Geotechnical Data Electrical Resistivity Method Standard Penetration Test (SPT) light dynamic Penetrometer (DPL) Mass Movements
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Study on the Dynamic Characteristics of Light Steel Residential Structural System 被引量:1
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作者 Wenwei Yang Qili Yang 《Engineering(科研)》 2017年第6期591-598,共8页
The study on the dynamic characteristics of light steel residential structural system has both theoretical and practical significance for the application and promotion of light steel residential structural system. In ... The study on the dynamic characteristics of light steel residential structural system has both theoretical and practical significance for the application and promotion of light steel residential structural system. In this paper, we analyze several common types of light steel residential structural system, describe the dynamic characteristics of the light steel residential structural system for an overview on the basis of former related studies, and then summarize the advantages of light steel residential structure system. 展开更多
关键词 light STEEL STRUCTURE RESIDENTIAL dynamic CHARACTERISTICS
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Spatio-temporal Dynamics of Urbanization in China Using DMSP/OLS Nighttime Light Data from 1992–2013 被引量:1
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作者 XU Pengfei LIN Muying JIN Pingbin 《Chinese Geographical Science》 SCIE CSCD 2021年第1期70-80,共11页
Understanding the dynamics of urbanization is essential to the sustainable development of cities. Meanwhile the analysis of urban development can also provide scientifically and effective information for decision-maki... Understanding the dynamics of urbanization is essential to the sustainable development of cities. Meanwhile the analysis of urban development can also provide scientifically and effective information for decision-making. With the long-term Defense Meteorological Satellite Program’s Operational Linescan System(DMSP/OLS) nighttime light images, a pixel level assessment of urbanization of China from 1992 to 2013 was conducted in this study, and the spatio-temporal dynamics and future trends of urban development were fully detected. The results showed that the urbanization and urban dynamics of China experienced drastic fluctuations from 1992 to 2013, especially for those in the coastal and metropolitan areas. From a regional perspective, it was found that the urban dynamics and increasing trends in North Coast China, East Coast China and South Coast China were much more stable and significant than that in other regions. Moreover, with the sustainability estimating of nighttime light dynamics, the regional agglomeration trends of urban regions were also detected. The light intensity in nearly 50% of lighted pixels may continuously decrease in the future, indicating a severe situation of urbanization within these regions. In this study, The results revealed in this study can provided a new insight in long time urbanization detecting and is thus beneficial to the better understanding of trends and dynamics of urban development. 展开更多
关键词 Defense Meteorological Satellite Program’s Operational Linescan System(DMSP/OLS)nighttime light URBANIZATION pixel level detection spatio-temporal dynamics future trends
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Effect of dynamic light at the coronary care unit on the length of hospital stay and development of delirium: a retrospective cohort study 被引量:2
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作者 Tobias Pustjens Antonius MC Schoutens +1 位作者 Loes Janssen Wilfred F Heesen 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第9期567-573,共7页
BackgroundDisturbed 生理节奏的节奏是谵妄的一个潜在的原因并且被连接到生理节奏的 rhythmicity 的 disorganisation。动态光(DL ) 能由 suprachiasmatic 原子核的激活重设生理节奏的节奏阻止谵妄。关于轻治疗的效果的证据主要集中于... BackgroundDisturbed 生理节奏的节奏是谵妄的一个潜在的原因并且被连接到生理节奏的 rhythmicity 的 disorganisation。动态光(DL ) 能由 suprachiasmatic 原子核的激活重设生理节奏的节奏阻止谵妄。关于轻治疗的效果的证据主要集中于精神病学的混乱和生理节奏的节奏睡觉混乱。在这研究,我们在停留(LOS ) 的全部的医院长度上调查了 DL 的效果,在病人的谵妄的出现承认 .MethodsThis 是回顾的队研究到联合起来的冠的照顾(CCU ) 。比 18 年老的病人,在 CCU 比 12 h 长被就医并且为至少 24 h 有全部的医院 LOS,被包括。病人们与 DL 被分到一个房间(n = 369 ) 或常规点亮条件(n = 379 ) 。DL 被与在 2700 和 6500 度凯尔文之间的颜色温度交付光的二块装天花板的轻面板在 CCU 管理。报导结果数据是:全部的医院 LOS,谵妄发生,一个老人病学者的会诊和 prescripted antipsychotics.ResultsBetween 2015 年 5 月和 2016 年 5 月的数量,从 748 个病人的数据被收集。包括挑起谵妄的风险因素,基线特征在两个组是相等的。在 DL 组的中部的全部的医院 LOS 是 100.5 (70.8-186.0 ) 并且 101.0 (73.0-176.4 ) 在控制组的 h (P = 0.935 ) 。在 DL 和控制组的谵妄的发生是 5.4%(20/369 ) 并且 5.0%(19/379 ) ,分别地(P = 0.802 ) 。DL 和控制组之间的重要差别都没在第二等的端点被观察。亚群分析也基于年龄和 CCU LOS 证明当一条早单个的途径不导致全部的医院 LOS 的减小或减少谵妄的发生,没有 differences.ConclusionOur 学习建议暴露到 DL。当谵妄被诊断时,它与差的医院结果被联系。 展开更多
关键词 医院 单位 长度 停留 生理节奏 开发 LOS CCU
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Dynamic Behavior and Mass Transport in Polyacrylic Acid Gel by Dynamic Light Scattering
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作者 JuZUO JianFengHUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第5期448-451,共4页
Dynamic behaviors on polyacrylic acid (PAA) gels and mass (small molecules) transports in the gels have been studied mainly by dynamic light scattering (DLS). The cross-linking degree (fc), monomer concentration (Cm)... Dynamic behaviors on polyacrylic acid (PAA) gels and mass (small molecules) transports in the gels have been studied mainly by dynamic light scattering (DLS). The cross-linking degree (fc), monomer concentration (Cm) and temperature of the gels have significant influences on its dynamic behavior and mass transport in the gels. The increase of fc leads to decrease of the mesh sizes of the gels, thus the obstacle of the gels for mass transport is increased. As a result, small molecular diffusion Dk in the gels is decreased. So even if for small molecules, the Dk also is influenced. 展开更多
关键词 Polyacrylic acid gel dynamic light scattering mass transport diffusion.
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DYNAMIC LIGHT SCATTERING STUDY ON TRANSLATION DIFFUSION OF 8-ARM STAR POLYSTYRENE IN GOOD AND THETA SOLVENTS
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作者 李峻柏 殷锐 +1 位作者 马荣久 沈家骢 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1992年第3期236-241,共6页
The technique of dynamic light scattering has been used to investigate the translation diffusion behavior of 8-arm star polystyrene (SPS)in a good solvent, tetrahydrofuran (THF) or benzene (BZ) and a theta solvent, cy... The technique of dynamic light scattering has been used to investigate the translation diffusion behavior of 8-arm star polystyrene (SPS)in a good solvent, tetrahydrofuran (THF) or benzene (BZ) and a theta solvent, cyclohexane (CH), by homodyne photon correlation spectroscopy .The intensityintensity autocorrelation function was analyzed by the method of cumulant. The translation diffusion coefficients have been obtained as a function of temperature and concentration. Under theta condition ,the non-concentration dependence of diffusion coefficient showed the unperturbed Gaussian state o the SPS molecular chain. The different hydrodynamic radii estimated from Stokes- Einstein equation reflected the stretch extent of the arm chain for regular star polymer. The data of diffusion activation energy of SPS in THF, BZ and CH were also obtained respectively. 展开更多
关键词 dynamic light scattering Star polystyrene Molecular diffusion
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Dynamical Casimir effect in superradiant light scattering by Bose Einstein condensate in an optomechanical cavity
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作者 Sonam Mahajan Neha Aggarwal +1 位作者 Aranya B Bhattacherjee ManMohan 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期151-160,共10页
We investigate the effects of dynamical Casimir effect in superradiant light scattering by Bose-Einstein condensate in an optomechanical cavity. The system is studied using both classical and quantized mirror motions.... We investigate the effects of dynamical Casimir effect in superradiant light scattering by Bose-Einstein condensate in an optomechanical cavity. The system is studied using both classical and quantized mirror motions. The cavity frequency is harmonically modulated in time for both the cases. The main quantity of interest is the number of intracavity scattered photons. The system has been investigated under the weak and strong modulations. It has been observed that the amplitude of the scattered photons is more for the classical mirror motion than the quantized mirror motion. Also, initially, the amplitude of scattered photons is high for lower modulation amplitude than higher modulation amplitude. We also found that the behavior of the plots are similar under strong and weak modulations for the quantized mirror motion. 展开更多
关键词 Bose-Einstein condensates dynamical Casimir effect superradiant light scattering optomechan- ical cavity
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Carrier Dynamics Determined by Carrier-Phonon Coupling in InGaN/GaN Multiple Quantum Well Blue Light Emitting Diodes
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作者 曹盛 吴小明 +1 位作者 刘军林 江风益 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第2期92-95,共4页
Phonon sidebands in the electrolumiescence(EL) spectra of InGaN/GaN multiple quantum well blue light emitting diodes are investigated. S-shaped injection current dependence of the energy spacing(ES) between the zero-p... Phonon sidebands in the electrolumiescence(EL) spectra of InGaN/GaN multiple quantum well blue light emitting diodes are investigated. S-shaped injection current dependence of the energy spacing(ES) between the zero-phonon and first-order phonon-assisted luminescence lines is observed in a temperature range of 100–150 K.The S-shape is suppressed with increasing temperature from 100 to 150 K, and vanishes at temperature above200 K. The S-shaped injection dependence of ES at low temperatures could be explained by the three stages of carrier dynamics related to localization states:(i) carrier relaxation from shallow into deep localization states,(ii) band filling of shallow and deep localization states, and(iii) carrier overflow from deep to shallow localization states and to higher energy states. The three stages show strong temperature dependence. It is proposed that the fast change of the carrier lifetime with temperature is responsible for the suppression of S-shaped feature.The proposed mechanisms reveal carrier recombination dynamics in the EL of InGaN/GaN MQWs at various injection current densities and temperatures. 展开更多
关键词 CARRIER dynamics Determined Carrier-Phonon Coupling INGAN/GAN Multiple Quantum Well BLUE light EMITTING DIODES
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EARLY CATARACT DETECTION BY DYNAMIC LIGHT SCATTERING WITH SPARSE BAYESIAN LEARNING
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作者 SU-LONG NYEO RAFAT R.ANSAR 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2009年第3期303-313,共11页
Dynamic light scattering(DLS)is a promising technique for early cataract detection and for studying cataractogenesis.A novel probabilistic analysis tool,the sparse Bayesian learning(SBL)algorithm,is described for reco... Dynamic light scattering(DLS)is a promising technique for early cataract detection and for studying cataractogenesis.A novel probabilistic analysis tool,the sparse Bayesian learning(SBL)algorithm,is described for reconstructing the most-probable size distribution ofα-crystallin and their aggregates in an ocular lens from the DLS data.The performance of the algorithm is evaluated by analyzing simulated correlation data from known distributions and DLS data from the ocular lenses of a fetal calf,a Rhesus monkey,and a man,so as to establish the required efficiency of the SBL algorithm for clinical studies. 展开更多
关键词 CATARACT dynamic light scattering diagnostic algorithm sparse Bayesian learning(SBL).
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The Dynamic Simulation of Rotary Inertia on Light vehicle-Slope I
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作者 Run Xu Boyong Hur 《Journal of Mechanical Engineering Research》 2020年第2期7-10,共4页
According to formula we can simulate their driven force and acceleration on the slope.The mechanical formula is used to obtain force and theoretical dynamics in the slope.The driven force decreases when rotation incre... According to formula we can simulate their driven force and acceleration on the slope.The mechanical formula is used to obtain force and theoretical dynamics in the slope.The driven force decreases when rotation increases.When power increases the acceleration increases.it reduces when its weight raises.It is found that the a will decrease as slope becomes high from 5 to 11°to 22°,which fit the formula too.Meantime as the radius is high from 0.3m to 0.4m to 0.47m a will be low.The needed force will increase as the slope decline becomes big at the same power. 展开更多
关键词 Simulation dynamic light vehicle ACCELERATION Turn bending Driven force TORQUE ROTATION SLOPE
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Development of a New Dynamic Lightweight Penetrometer for the Determination of Mechanical Properties of Fine-Grained Soils
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作者 Bao Thach Nguyen Abbas Mohajerani 《Journal of Civil Engineering and Architecture》 2012年第10期1417-1422,共6页
关键词 细粒土 力学性能 测定 触探 轻型 CBR值 加州承载比 移动设备
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Polarized imaging dynamic light scattering for simultaneous measurement of nanoparticle size and morphology
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作者 Bingyao Wang Tianyi Cai +2 位作者 Xiaoshu Cai Wu Zhou Zeqi Liu 《Particuology》 SCIE EI CAS CSCD 2024年第2期213-223,共11页
The performance of nanoparticles is often affected by particle size and morphology.Currently,electron microscopy or atomic force microscopy is typically utilized to determine the size and morphology of nanoparticles.H... The performance of nanoparticles is often affected by particle size and morphology.Currently,electron microscopy or atomic force microscopy is typically utilized to determine the size and morphology of nanoparticles.However,there are issues such as difficult sample preparation,long processing times,and challenges in quantitative characterization.Therefore,it is of great significance to develop a fast,accu-rate,and statistical method to measure the size and morphology of nanoparticles.In this study,a new method,called polarized imaging dynamic light scattering(PIDLS),is proposed.The nanoparticles are irradiated with a vertical linearly polarized laser beam,and a polarization camera collected the dynamic light scattering images of particles at four different polarization directions(0°,45°,90°,and 135°)at a scattering angle of 90°.The average particle size and distribution are obtained using the imaging dy-namic light scattering method at 0°polarization direction,and the morphology of the particles is ob-tained based on the depolarization patterns of the scattered light.The optical sphericityΦis defined based on the degree of linear polarization(DoLP).It is also implemented for the quantitative evaluation of the sphericity of the nanoparticles,including spherical,octahedral,nanoplate,nanorod,and linear ones.Together with the Poincarésphere parameterψ,the morphology of the nanoparticles can be roughly identified.In addition,PIDLS enables the measurement of particle size and morphology distributions simultaneously for evaluating the uniformity of particles.The effectiveness of PIDLS is verified by the measurement of five kinds of industrial titanium dioxide as well. 展开更多
关键词 Imaging dynamic light scattering Polarized light scattering Non-spherical nanoparticles MORPHOLOGY Online measurement
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A regularization algorithm of dynamic light scattering for estimating the particle size distribution of dual-substance mixture in water
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作者 Yanghong Wang Ziqiang Meng +3 位作者 Zipei Zhang Min Xia Li Xia Wei Li 《Particuology》 SCIE EI CAS CSCD 2024年第6期246-257,共12页
Dynamic light scattering(DLS)is a nondestructive,well-established technique for the size characterization of proteins,nanoparticles,polymers,and colloidal dispersions.However,current DLS techniques are only applied to... Dynamic light scattering(DLS)is a nondestructive,well-established technique for the size characterization of proteins,nanoparticles,polymers,and colloidal dispersions.However,current DLS techniques are only applied to particle groups of single composition due to the limitation of their inversion algorithm.In this study,we propose a particle size distribution inversion algorithm based on the Tikhnonov regularization method that can be applied to the dual-substance particle mixture.The algorithm retrieves the particle size distributions of two substances,respectively,by taking advantage of their refractive index differences.The simulation results reveal that the algorithm has excellent accuracy and stability when the scattering angle is 30°.Instead of the original identity matrix,the first-order difference matrix and second-order difference matrix are used as the regular matrix when utilizing the Tikhnonov algorithm,which obviously improves the anti-interference,accuracy,and stability of the algorithm.Furthermore,the inversion of particle size distribution is carried out at a 0.01%–1%noise level,which shows that the algorithm has an available antinoise ability.Finally,experimental particle size measurements for a mixture of polystyrene beads and toner particles demonstrate that the proposed algorithm is superior to the traditional Tikhnonov algorithm in applicability and accuracy. 展开更多
关键词 dynamic light scattering Dual-substance mixture Particle sized istribution Tikhnonov regularization
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Applying dynamic light scattering to investigate the self-assembly process of DNA nanostructures
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作者 Wei Yuan Gui-Zhi Dong +7 位作者 Hui Ning Xiang-Xiang Guan Jia-Feng Cheng Zi-Wei Shi Xiu-Ji Du Si-Wen Meng Dong-Sheng Liu Yuan-Chen Dong 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第3期316-320,共5页
Understanding the dynamic assembly process of DNA nanostructures is important for developing novel strategy to design and construct functional devices.In this work,temperature-controlled dynamic light scattering(DLS)s... Understanding the dynamic assembly process of DNA nanostructures is important for developing novel strategy to design and construct functional devices.In this work,temperature-controlled dynamic light scattering(DLS)strategy has been applied to study the global assembly process of DNA origami and DNA bricks.Through the temperature dependent size and intensity profiles,the self-assembly process of various DNA nanostructures with different morphologies have been well-studied and the temperature transition ranges could be observed.Taking advantage of the DLS information,rapid preparation of the DNA origami and the brick assembly has been realized through a constant temperature annealing.Our results demonstrate that the DLS-based strategy provides a convenient and robust tool to study the dynamic process of forming hieratical DNA structures,which will benefit understanding the mechanism of self-assembly of DNA nanostructures. 展开更多
关键词 dynamic light scattering Self-assembly process DNA nanostructures Temperature transition ranges Rapid preparation
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Study of asphaltene reaggregation in toluene/heptane mixture by dynamic and static light scattering
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作者 Vladimir N.Kuryakov 《Petroleum Research》 EI 2024年第1期48-54,共7页
This paper presents the study of the effect of multiple ultrasonic impacts on submicron asphaltene aggregates in a toluene/heptane solution,conducted with dynamic light scattering technique.The objects of the study we... This paper presents the study of the effect of multiple ultrasonic impacts on submicron asphaltene aggregates in a toluene/heptane solution,conducted with dynamic light scattering technique.The objects of the study were four samples of asphaltenes obtained from four different oils.For all samples,the change in the average size of the asphaltene submicron aggregates with time was measured after the addition of a precipitant(heptane)to a solution of asphaltenes in toluene at an amount above the threshold concentration.Asphaltene aggregates formed in solution after the addition of the precipitant and were subjected to ultrasonic treatment,which led to the destruction of the asphaltene aggregates.Aggregation of destroyed asphaltenes was observed.The kinetics of this aggregation were similar to the kinetics of aggregation of asphaltenes after the addition of a precipitant.Multiple iterations of asphaltene aggregate destruction in the sample led to a significant change in the kinetics of aggregation:the growth of aggregates slowed and stabilized at a size of approximately 200 nm and 30 nm for the different studied samples. 展开更多
关键词 ASPHALTENES AGGREGATION Sonication dynamic light scattering Re-aggregation Colloidal stability Resins
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Graphene-empowered dynamic metasurfaces and metadevices 被引量:9
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作者 Chao Zeng Hua Lu +4 位作者 Dong Mao Yueqing Du He Hua Wei Zhao Jianlin Zhao 《Opto-Electronic Advances》 SCIE EI 2022年第4期1-47,共47页
Metasurfaces,with extremely exotic capabilities to manipulate electromagnetic(EM)waves,have derived a plethora of advanced metadevices with intriguing functionalities.Tremendous endeavors have been mainly devoted to t... Metasurfaces,with extremely exotic capabilities to manipulate electromagnetic(EM)waves,have derived a plethora of advanced metadevices with intriguing functionalities.Tremendous endeavors have been mainly devoted to the static metasurfaces and metadevices,where the functionalities cannot be actively tuned in situ post-fabrication.Due to the in-trinsic advantage of active tunability by external stimulus,graphene has been successively demonstrated as a favorable candidate to empower metasurfaces with remarkably dynamic tunability,and their recent advances are propelling the EM wave manipulations to a new height:from static to dynamic.Here,we review the recent progress on dynamic metasur-faces and metadevices enabled by graphene with the focus on electrically-controlled dynamic manipulation of the EM waves covering the mid-infrared,terahertz,and microwave regimes.The fundamentals of graphene,including basic ma-terial properties and plasmons,are first discussed.Then,graphene-empowered dynamic metasurfaces and met-adevices are divided into two categories,i.e.,metasurfaces with building blocks of structured graphene and hybrid metasurfaces integrated with graphene,and their recent advances in dynamic spectrum manipulation,wavefront shap-ing,polarization control,and frequency conversion in near/far fields and global/local ways are elaborated.In the end,we summarize the progress,outline the remaining challenges,and prospect the potential future developments. 展开更多
关键词 metasurface dynamic metasurface GRAPHENE graphene plasmons light field manipulation electromagnetic wave manipulation
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Dynamic Modelling of VFC from 2000 to 2010 Using NDVI and DMSP/OLS Time Series: A Study in Guangdong Province, China 被引量:1
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作者 Seyed Omidreza Shobairi Mingyang Li 《Journal of Geographic Information System》 2016年第2期205-223,共19页
Forest cover change is considered one of the serious issues in the last several decades for the global environment. This scenario has mainly depended to ever-increasing socio-economic activities. The present article h... Forest cover change is considered one of the serious issues in the last several decades for the global environment. This scenario has mainly depended to ever-increasing socio-economic activities. The present article has revealed major changes of VFC in relation to human activities during the years of 2000 to 2010 in the Guangdong province of China. The data derived using the NDVIimages. The analysis covered the growing season which consisted of seven months (April to October) annually. VFC (Vegetation Fractional Cover) was successfully calculated from NDVI images and VFC levels were defined in four levels. Levels IV and I had the highest and lowest annual changes. Areas at risk of desertification and difference coverage were determined by Hot Spot and Cold Spot analyzing. Mean of total VFC was evaluated 0.783 and Moran’s I statistic calculated for years separately. Additionally, Light Index achieved of DMSP/OLS data annually. The results show that VFC and Light Index have an upward trend, which means that development of social economy leads to increasing awareness of the importance of environmental protection and sustainable development. Hereof, we witness seven-year increase of VFC during the eleven years. The correlation co-efficient shows that Light Index is suitable index for evaluating diving forces. Time series modeling confirms that there is strong inverse relationship between the VFC and Light Index in most cases. This means with increasing Light Index, VFC decreases. Finally, driving forces of VFC variation show that forest cover change scenario is more under the influence of the human activities. 展开更多
关键词 VFC light Index Human Activity dynamic
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The “Dynamic Gravitation of Photons: A Hitherto Unknown Physical Quantity”. New Aspects on the Physics of Photons 被引量:1
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作者 Guido Zbiral 《Journal of Modern Physics》 2014年第5期198-204,共7页
In order to explore the nature of photons, no doubts can be allowed to exist concerning the “physics of photons”. While static gravitation plays no role in the physics of photons, this paper will show that the previ... In order to explore the nature of photons, no doubts can be allowed to exist concerning the “physics of photons”. While static gravitation plays no role in the physics of photons, this paper will show that the previously unknown nonbaryonic dynamic gravitation of photons determines not only the external physical behaviour of photons but also, in particular, the hitherto unknown physical events occurring within the photons themselves. For this reason, the paper places particular emphasis on dynamic gravitation as a new hitherto unknown physical quantity. Moreover the new type of gravitation postulated here also provides a plausible explanation of the mysterious nonbaryonic dark matter. As no generally accepted scientific explanation of the creation and essence of dark matter exists to date, it is to be anticipated that the nonbaryonic dynamic gravitation of photons is of general interest to physicists as well as cosmologists and may serve to initiate a general debate among them. Furthermore, this paper will also show that there exists a close mutual relationship between electrodynamics dynamic gravitation static gravitation electrostatics electrodynamics (refer to paragraph 4). Due to the fact that the insights into the relationship between photons and their dynamic gravitation have not been described by any other author to date, there exists only a few references that I can cite in support of my paper. 展开更多
关键词 PHOTONS Speed of light Baryonic (Static) GRAVITATION Nonbaryonic dynamic GRAVITATION Nonbaryonic STATIC GRAVITATION (Dark Matter) GRAVITATIONAL Quanta
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River Flow Control on the Phytoplankton Dynamics of Chesapeake Bay 被引量:1
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作者 YU Qingyun WANG You +1 位作者 TANG Xuexi LI Ming 《Journal of Ocean University of China》 SCIE CAS 2013年第1期103-114,共12页
Recent observations support an emerging paradigm that climate variability dominates nutrient enrichment in costal eco-systems, which can explain seasonal and inter-annual variability of phytoplankton community composi... Recent observations support an emerging paradigm that climate variability dominates nutrient enrichment in costal eco-systems, which can explain seasonal and inter-annual variability of phytoplankton community composition, biomass (Chl-a), and primary production (PP). In this paper, we combined observation and modeling to investigate the regulation of phytoplankton dynamics in Chesapeake Bay. The year we chose is 1996 that has high river runoff and is usually called a 'wet year'. A 3-D physical-biogeochemical model based on ROMS was developed to simulate the seasonal cycle and the regional distributions of phytoplankton biomass and primary production in Chesapeake Bay. Based on the model results, NO3 presents a strong contrast to the river nitrate load during spring and the highest concentration in the bay reaches around 80 mmol Nm-3 . Compared with the normal year, phytoplankton bloom in spring of 1996 appears in lower latitudes with a higher concentration. Quantitative comparison between the modeled and observed seasonal averaged dissolved inorganic nitrogen concentrations shows that the model produces reliable results. The correlation coefficient r2 for all quantities exceeds 0.95, and the skill parameter for the four seasons is all above 0.95. 展开更多
关键词 浮游植物生物量 切萨皮克湾 动力学 流量控制 模型模拟 沿海生态系统 生物地球化学 初级生产
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