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The Road to Reengagement and Beyond

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Beijing Review 2022年第10期65卷 30-31页

作者： mitchell f.stanley the National Center for Sustainable Development in Washington D.C.

The Shanghai Communiqué, a pathbreaking accord signed by U.S. President Richard Nixon and Chinese Premier Zhou Enlai on february 28, 1972, marks a defining moment in the history of both the United States and the Peo... 详细信息

关键词： breaking Road Beyond

CERTAINTY MUST BE RESTORED

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Beijing Review 2021年第4期64卷 24-25页

作者： mitchell f.stanley Tao Xing National Center for Sustainable Development(NCSD) Beijing Review

*** cooperation has experienced a roller-coaster ride over the past few *** way will it head under Joe Biden?mitchell ***,Chairman of the National Center for Sustainable Development(NCSD)in Washington,D.C.,shares his observations with Beijing Review reporter Tao *** is an edited excerpt of the interview:Beijing Review:According to forbes,the *** become the world’s largest oil and gas exporter in the next few *** is the world’s largest importer of crude oil,and the *** for 7 percent of China’s imports through mid-September 2020,according to London-based market intelligence firm Vortexa *** can the two countries expand their energy cooperation?

关键词： interview roller cooperation

AdS/QCD and light front holography: A new approximation to QCD

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Chinese Physics C 2010年第9期34卷 1229-1235页

作者： stanley J.Brodsky Guy f.de Téramond SLAC National Accelerator Laboratory Stanford University Universidad de Costa Rica

The combination of Anti-de Sitter space （AdS） methods with light-front holography leads to a semi-classical first approximation to the spectrum and wavefunctions of meson and baryon light-quark bound *** from the bound-state Hamiltonian equation of motion in QCD,we derive relativistic lightfront wave equations in terms of an invariant impact variable ζ which measures the separation of the quark and gluonic constituents within the hadron at equal light-front *** equations of motion in physical space-time are equivalent to the equations of motion which describe the propagation of spin-J modes in anti–de Sitter （AdS） *** eigenvalues give the hadronic spectrum,and its eigenmodes represent the probability distributions of the hadronic constituents at a given *** to the light meson and baryon spectra are *** predicted meson spectrum has a string-theory Regge form M^ 2 = 4κ ^2 （n＋L＋S/2）;i.e.,the square of the eigenmass is linear in both L and n,where n counts the number of nodes of the wavefunction in the radial variable ζ.The space-like pion and nucleon form factors are also well *** thus obtains a remarkable connection between the description of hadronic modes in AdS space and the Hamiltonian formulation of QCD in physical space-time quantized on the light-front at fixed light-front time τ.The model can be systematically improved by using its complete orthonormal solutions to diagonalize the full QCD lightfront Hamiltonian or by applying the Lippmann-Schwinger method in order to systematically include the QCD interaction terms.

关键词： gauge/gravity correspondence light-front dynamics strongly coupled QCD meson and baryon spectrum meson and nucleon form factors

AdS/QCD and Applications of Light-front Holography

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Communications in Theoretical Physics 2012年第4期57卷 641-664页

作者： stanley J.Brodsky Guy f.de Téramond CAO Pu-Guang SLAC National Accelerator Laboratory Stanford University Stanford CA 94309 USA and CPa-Origins Southern Denmark University Odense Denmark Massey University Palmerston North New Zealand Universidad de Costa Rica San Jose Costa Rica

Light-front holography leads to a rigorous connection between hadronic amplitudes in a higher dimensional anti-de Sitter(AdS) space and frame-independent light-front wavefunctions of hadrons in(3 + 1)-dimensional physical space-time,thus providing a compelling physical interpretation of the AdS/CfT correspondence principle and AdS/QCD,a useful framework which describes the correspondence between theories in a modified AdS 5 background and confining field theories in physical *** a first semiclassical approximation,where quantum loops and quark masses are not included,this approach leads to a single-variable light-front Schro¨dinger equation which determines the eigenspectrum and the light-front wavefunctions of hadrons for general spin and orbital angular *** coordinate z in AdS space is uniquely identified with a Lorentz-invariant coordinate ζ which measures the separation of the constituents within a hadron at equal light-front *** internal structure of hadrons is explicitly introduced and the angular momentum of the constituents plays a key *** give an overview of the light-front holographic approach to strongly coupled *** particular,we study the photon-to-meson transition form factors(Tffs) fMγ(Q 2) for γ→ M using light-front holographic *** results for the Tffs for the η and η ' mesons are also *** novel features of QCD are discussed,including the consequences of confinement for quark and gluon condensates.A method for computing the hadronization of quark and gluon jets at the amplitude level is outlined.

关键词： gauge/gravity correspondence light-front dynamics strongly coupled QCD meson and baryon spectrum meson and nucleon form factors

Circularly and elliptically polarized light under water and the Umov effect

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Light(Science & Applications) 2019年第1期8卷 901-906页

作者： Yitian Ding stanley Pau College of Optical Sciences University of ArizonaTucsonAZ 85721USA

Total internal reflection occurs when light is incident on the interface of high-and low-refractive-index materials at an angle greater than the critical *** with high degree of linear polarization,such as atmospheric scattered skylight,can be converted with a high efficiency up to 53%to circular and elliptical polarizations by total internal reflection under water in the region outside Snell’s *** degree of circular polarization is observed to be inversely dependent on the albedo of underwater objects and is shown to be a direct consequence of the Umov *** results are important for underwater polarimetry,surveillance applications and studies of marine animals’polarized vision near the water-air interface.

关键词： effect. polarized underwater

PHASE EQUILIBRIUM Of COMPLEX MIXTURES WITH EQUATIONS Of STATE: AN UPDATE5

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Chinese Journal of Chemical Engineering 1995年第1期3卷 42-53页

作者： stanley I.Sandler Hasan orbey Center for Molecular and Engineering Thermodynamics Department of Chemical EngineeringUniversity of DelawareNewarkDE 19716 USACenter for Molecular and Engineering ThermodynamicsDepartment of Chemical EngineeringUniversity of DelawareNewarkDE 19716 USA

Here we review a new class of mixing rules (hat have extended range of mixtures and conditions that can now be described by equation of state models. One characteristic of these mixing rules is that they simultaneously satisfy the boundary conditions of producing a second virial coefficient that is quadratic in mole fraction, and a free energy of mixing like that of an activity coefficient model at high density, though the mixing rule is itself independent of density. We show that using this mixing rule, various asymmetric, highly nonideal mixtures can be accurately described. One serendipitous result is that the parameters in this mixing rule model are almost independent of temperature, which allows accurate extrapolations of phase behavior to be made over large ranges of temperature and pressure.

关键词： equations of state mixing rules phase equilibrium complex mixtures

Spontaneous Recovery in Directed Dynamical Networks

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Engineering 2024年第6期37卷 208-214页

作者： Xueming Liu Xian Yan H.Eugene stanley School of Artificial Intelligence and Automation&The MOE Engineering Research Center of Autonomous Intelligent Unmanned Systems&the Key Laboratory of Image Processing Huazhong University of Science and TechnologyWuhan 430074China Center for Polymer Studies Department of PhysicsBoston UniversityBostonMA 02215USA

Complex networked systems,which range from biological systems in the natural world to infrastructure systems in the human-made world,can exhibit spontaneous recovery after a failure;for example,a brain may spontaneously return to normal after a seizure,and traffic flow can become smooth again after a *** studies on the spontaneous recovery of dynamical networks have been limited to undirected ***,most real-world networks are *** fill this gap,we build a model in which nodes may alternately fail and recover,and we develop a theoretical tool to analyze the recovery properties of directed dynamical *** find that the tool can accurately predict the final fraction of active nodes,and the prediction accuracy decreases as the fraction of bidirectional links in the network increases,which emphasizes the importance of directionality in network *** to different initial states,directed dynamical networks may show alternative stable states under the same control parameter,exhibiting hysteresis *** addition,for networks with finite sizes,the fraction of active nodes may jump back and forth between high and low states,mimicking repetitive failure-recovery *** findings could help clarify the system recovery mechanism and enable better design of networked systems with high resilience.

关键词： Network resilience Directed dynamical networks Spontaneous recovery

An Example Using Improved Lefschetz Duality

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Chinese Annals of Mathematics,Series B 2017年第6期38卷 1269-1274页

作者： Pascal LAMBRECHTS Jeremy LANE Donald stanley Pascal Lambrechts Institut Mathmatique Universit de Louvain Department of Mathemtics University of Toronto Department of Mathematics and Statistics University of Regina

A theorem of Lambrechts and stanley is used to find the rational cohomology of the complement of an embedding S^(4n-1)→ S^(2n)× S^m as a module and demonstrate that it is not necessarily determined by the map induced on cohomology by the embedding, nor is it a trivial extension. This demonstrates that the theorem is an improvement on the classical Lefschetz duality.

关键词： Lefschetz duality Embedding Extension problem

Analysis of drying and saturating natural gypsum samples for mechanical testing

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第2期11卷 219-227页

作者： Mohammadhossein Sadeghiamirshahidi stanley J.Vitton Department of Civil and Environmental Engineering Michigan Technological University

The stability of underground abandoned gypsum mines is dependent on the gypsum pillar's strength,and most abandoned mines are in a fully saturated condition. Moisture affects the strength of gypsum and is therefore commonly measured when testing rock strength. for most rocks, this is a simple task of weighing the rock's mass before and after oven-heating at a specified temperature and duration. for natural gypsum, however, this is not a straightforward process. Heating natural gypsum can result in dehydration and transformation of gypsum to hemihydrate and anhydrite, thus changing the physical characteristics of the gypsum such as its particle density which in turn affects the moisture content and strength measurements. To prevent transformation when determining the moisture content of gypsum,the American Society for Testing Materials(ASTM) recommends lowering the drying temperature from 110℃ to 60℃ . To investigate the temperature at which gypsum transforms to hemihydrate, we used a helium pycnometer to measure the particle densities of gypsum, hemihydrate and anhydrite. In this research, we suggest that a higher drying temperature of 80℃ can be used for drying gypsum without transforming gypsum to hemihydrate. further, preparing saturated samples for mechanical testing,which is required in stability analyses of abandoned mines, is challenging due to the dissolution of gypsum when placed in water. To address this problem, we investigated the following methods to saturate gypsum cores taking into account the solubility of gypsum:(1) water immersion,(2) vacuum saturation, and(3) improved vacuum saturation. The research indicates that all the three methods are acceptable but they should be conducted using a saturated gypsum-water solution to minimize dissolution. further, the research found that the improved vacuum saturation method saturated the test samples within 24 h, while duration of 30 h was required for the other two methods.

关键词： Gypsum-hemihydrate-anhydrite transformation Dehydration Rock core saturation Moisture content Helium pycnometer