scholarly journals ELECTROMAGNETIC TRANSITIONS WITH EFFECTIVE OPERATORS

2005 ◽  
Vol 14 (01) ◽  
pp. 95-103 ◽  
Author(s):  
IONEL STETCU ◽  
BRUCE R. BARRETT ◽  
PETR NAVRÁTIL ◽  
CALVIN W. JOHNSON
Keyword(s):  
Effective Interaction ◽  
The Other ◽  
Core Shell ◽  
Body System ◽  
Cluster Approximation ◽  
Expectation Values ◽  
Model Spaces ◽  
Reduced Space ◽  
Model Formalism ◽  
Effective Operators

In the no-core shell model formalism we compute effective one- and two-body operators, using the Lee–Suzuki procedure within the two-body cluster approximation. We evaluate the validity of the latter through calculations in reduced model spaces. In particular, we test the results for the two-body system and find that indeed the effective operators in the reduced space reproduce the expectation values or transition strengths computed in the full space. On the other hand, the renormalization for operators in the case of 6Li is very weak, suggesting the need for higher-body clusters in computing the effective interaction.

scholarly journals Properties of infrared extrapolations in a harmonic oscillator basis

2016 ◽  
Vol 25 (05) ◽  
pp. 1641011 ◽  
Author(s):  
Sidney A. Coon ◽  
Michael K. G. Kruse
Keyword(s):  
Effective Field Theory ◽  
Ground State ◽  
Effective Field ◽  
The Other ◽  
Ab Initio Methods ◽  
Harmonic Oscillator Basis ◽  
Expectation Values ◽  
Oscillator Basis ◽  
Model Spaces ◽  
Ground State Energies

The success and utility of effective field theory (EFT) in explaining the structure and reactions of few-nucleon systems has prompted the initiation of EFT-inspired extrapolations to larger model spaces in ab initio methods such as the no-core shell model (NCSM). In this contribution, we review and continue our studies of infrared (ir) and ultraviolet (uv) regulators of NCSM calculations in which the input is phenomenological [Formula: see text] and [Formula: see text] interactions fitted to data. We extend our previous findings that an extrapolation in the ir cutoff with the uv cutoff above the intrinsic uv scale of the interaction is quite successful, not only for the eigenstates of the Hamiltonian but also for expectation values of operators, such as [Formula: see text], considered long range. The latter results are obtained with Hamiltonians transformed by the similarity renormalization group (SRG) evolution. On the other hand, a possible extrapolation of ground state energies in the uv cutoff when the ir cutoff is below the intrinsic ir scale is not robust and does not agree with the ir extrapolation of the same data or with independent calculations using other methods.

Effect of glycidyl methacrylate (GMA) on the stability of acrylic latex

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Guangfeng Wu ◽  
Yue Tao ◽  
Hong Kang ◽  
Huixuan Zhang
Keyword(s):  
Experimental Data ◽  
Glycidyl Methacrylate ◽  
Sodium Dodecyl ◽  
The Other ◽  
Lower Amount ◽  
Core Shell ◽  
Acrylic Latex ◽  
The Core ◽  
Shell Particles ◽  
The Stability

AbstractThe stability of core-shell particles (CSPs) with butyl acrylate (BA) as the core and methyl methacrylate (MMA)/glycidyl methacrylate (GMA) mixture in various compositions as the shell was investigated by turbidity measurements. The experiments demonstrate that lower amount addition of GMA could not improve the latex stability. When the amount of GMA exceeded 2% of the total reactants, it began to improve the stability of the latex. With the increasing content of GMA, the latex became more and more stable. On the other hand, experimental data also show that the stability was improved by increasing the concentration of sodium dodecyl sulfate (SDS).

Poly(amide) oligomers with silarylene and/or germarylene units – synthesis, characterization and thermal studies

e-Polymers ◽  
2009 ◽  
Vol 9 (1) ◽  
Author(s):  
Luis H. Tagle ◽  
Claudio A. Terraza ◽  
Angel Leiva ◽  
Patricia Alvarez
Keyword(s):  
Main Chain ◽  
Effective Interaction ◽  
Thermal Studies ◽  
The Other ◽  
Spectroscopic Techniques ◽  
Aromatic Diamines ◽  
Packing Factor ◽  
Degradation Temperature ◽  
General Terms ◽  
Acid Dichloride

AbstractTen poly(amide) oligomers were prepared from four acid dichlorides and two full-aromatic diamines, the latter containing silicon or germanium in their structure. The polymers, which contain Et/Me, Et/Et and nBu/nBu combinations on heteroatom of the acid dichloride moiety, were characterized by spectroscopic techniques, including 29Si NMR. The yields obtained and the ηιnh values established were low, indicating the low molecular weight nature of the polymers. Thermal stability was also evaluated by TG and DSC techniques. When a methyl group was replaced by a Et, the Tg of the poly(amides) (PAs) was increased in accordance with the gain in the flexibility of the chain. However and in general terms, the PAs with nBu groups show the inverse effect. Probably, the possibility of an effective interaction between these side chains affects negatively the flexibility of the main chain. On the other hand, PAs that contain single silicon in their structure show lower Tg values than the Ge-containing PAs. For the other heteroatom combinations, similar results were obtained. This fact does not agree with the lower size of silicon atom which should increase the molecular rigidity and therefore their Tg values. Probably, the influence of the side groups is decisive in hindering the chain rotation. The thermal degradation temperature (TDT) changed in agreement with the packing factor of the chains which was depending on the size of substitute groups. So, when Et group was replaced by nBu as lateral group, lower TDT were recovered. With respect to the heteroatoms used in the main chain, the TDT values do not show a clear tendency.

Extended Camus Theory and Higher Order Conjugated Curves

2019 ◽  
Author(s):  
Cody Leeheng Chan ◽  
Kwun-Lon Ting
Keyword(s):  
Stationary Point ◽  
Higher Order ◽  
The Body ◽  
The Other ◽  
Body System ◽  
Straight Line ◽  
Pair Generation ◽  
Curvature Theory ◽  
Three Body ◽  
Two Bodies

Abstract According to Camus’ theorem, for a single DOF 3-body system with the three instant centers staying coincident, a point embedded on a body traces a pair of conjugated curves on the other two bodies. This paper discusses a fundamental issue not addressed in Camus’ theorem in the context of higher order curvature theory. Following the Aronhold-Kennedy theorem, in a single degree-of-freedom three-body system, the three instant centers must lie on a straight line. This paper proposes that if the line of the three instant centers is stationary (i.e. slide along itself), on the line of the instant centers a point embedded on a body traces a pair of conjugated curves on the other two bodies. Another case is that if the line of the three instant centers rotate about a stationary point, the stationary point embedded on the body also traces a pair of conjugated curves on the other two bodies. The paper demonstrates the use of instantaneous invariants to synthesize such a three-body system leading to a conjugate curve-pair generation. It is a supplement or extension of the Camus’ theorem. The Camus’ theorem may be regarded as a special singular case, in which all three instant centers are coincident.

Ferromagnetic ZnO-TiO2 Core-Shell Nanowire PhotoCatalyst with High Efficiency and Recyclability

2011 ◽  
Vol 90-93 ◽  
pp. 1702-1705
Author(s):  
Xi Zhang ◽  
Gang Xiang
Keyword(s):  
High Efficiency ◽  
Hole Concentration ◽  
Band Gaps ◽  
The Other ◽  
Band Edge ◽  
Core Shell ◽  
Hole Density ◽  
The Core ◽  
Recyclable Photocatalyst ◽  
Shell Nanowires

We demonstrate the design of the recyclable photocatalyst based on ferromagnetic (FM) ZnO- TiO2 core-shell nanowires (NWs). Since the band gaps and band edge energies of bulk ZnO and anatase TiO2 are equal to each other within about 45mV, TiO2 and ZnO can form an p-p+ heterojunction free of band discontinuities and with a built-in potential. The resulting radial field will increase hole density in the TiO2 layer while reduce hole concentration at the interface between the core and the shell, which in turn will decrease the rate of recombination in the photocatalytic TiO2, and hence increase the efficiency of photocatalyst. On the other hand, the NWs with FM cores can be easily collected and refreshed using solenoid and suitable for the recyclable usage of the NW catalyst

scholarly journals Complete complementarity relations and their Lorentz invariance

2021 ◽  
Vol 477 (2253) ◽  
pp. 20210058
Author(s):  
Marcos L. W. Basso ◽  
Jonas Maziero
Keyword(s):  
Quantum System ◽  
Lorentz Invariance ◽  
Entanglement Entropy ◽  
The Other ◽  
Entangled State ◽  
Lorentz Frame ◽  
Expectation Values ◽  
Wave Particle Duality ◽  
Lorentz Boosts ◽  
Spin Momentum

It is well known that entanglement under Lorentz boosts is highly dependent on the boost scenario in question. For single-particle states, a spin-momentum product state can be transformed into an entangled state. However, entanglement is just one of the aspects that completely characterizes a quantum system. The other two are known as the wave-particle duality. Although the entanglement entropy does not remain invariant under Lorentz boosts, and neither do the measures of predictability and coherence, we show here that these three measures taken together, in a complete complementarity relation (CCR), are Lorentz invariant. Peres et al. (Peres et al. 2002 Phys. Rev. Lett. 88 , 230402. ( doi:10.1103/PhysRevLett.88.230402 )) realized that even though it is possible to formally define spin in any Lorentz frame, there is no relationship between the observable expectation values in different Lorentz frames. Analogously, one can, in principle, define complementary relations in any Lorentz frame, but there is no obvious transformation law relating complementary relations in different frames. However, our result shows that the CCRs have the same value in any Lorentz frame, i.e. there is a transformation law connecting the CCRs. In addition, we explore relativistic scenarios for single and two-particle states, which helps in understanding the exchange of different aspects of a quantum system under Lorentz boosts.

Quantum Quench and Universal Scaling

2020 ◽  
Author(s):  
Sumit R. Das
Keyword(s):  
Cold Atom ◽  
The Other ◽  
Critical Dynamics ◽  
Quantum Field ◽  
Body System ◽  
Many Body ◽  
Adiabatic Evolution ◽  
Universal Scaling ◽  
Quantum Quench ◽  
Nonequilibrium Physics

A quantum quench is a process in which a parameter of a many-body system or quantum field theory is changed in time, taking an initial stationary state into a complicated excited state. Traditionally “quench” refers to a process where this time dependence is fast compared to all scales in the problem. However in recent years the terminology has been generalized to include smooth changes that are slow compared to initial scales in the problem, but become fast compared to the physical scales at some later time, leading to a breakdown of adiabatic evolution. Quantum quench has been recently used as a theoretical tool to study many aspects of nonequilibrium physics like thermalization and universal aspects of critical dynamics. Relatively recent experiments in cold atom systems have implemented such quench protocols, which explore dynamical passages through critical points, and study in detail the process of relaxation to a steady state. On the other hand, quenches which remain adiabatic have been explored as a useful technique in quantum computation.

scholarly journals The International Criminal Tribunal for the Former Yugoslavia and Fair Trial Rights: A Closer Look

1996 ◽  
Vol 9 (2) ◽  
pp. 479-501 ◽  
Author(s):  
James Sloan
Keyword(s):  
Human Rights ◽  
United Nations ◽  
Recent Article ◽  
International Criminal ◽  
International Criminal Tribunal ◽  
The Other ◽  
Former Yugoslavia ◽  
Body System ◽  
European Court ◽  
Treaty Body

In a recent article lamenting the perception of partiality created by an activist judge of the International Criminal Tribunal for the former Yugoslavia (ICTY), one commentator observed the general lack of scrutiny to which the ICTY is being held in its treatment of the rights of the accused. He noted that it “is a court without legal critics: no complaint about its conduct may be made to the Human Rights Committee in Geneva or to the European Court [of Human Rights], and human rights lobbies have tended to look the other way.” Indeed, it is in a position that many governments, fatigued by what many of them consider to be cumbersome reporting obligations and troublesome individual complaints procedures under the United Nations treaty body system, would envy.

Intermediate Effective Operators in Valence-Bond Model Spaces

1991 ◽  
Vol 02 (01) ◽  
pp. 549-551
Author(s):  
A.V. ZAITSEVSKII ◽  
A.I. DEMENT’EV
Keyword(s):  
Ab Initio ◽  
Valence Bond ◽  
Effective Operator ◽  
Atomic Orbitals ◽  
Bond Model ◽  
Model Spaces ◽  
Operator Construction ◽  
State Functions ◽  
Effective Operators

We developed and implemented an algorithm of ab initio intermediate effective operator construction for model spaces spanned by valence-bond-like configuration state functions built from orthogonalized atomic orbitals.

Synthesis and microstructure of conformal coatings on particulates

1997 ◽  
Vol 501 ◽  
Author(s):  
K. Rajan ◽  
P. Sajgalik ◽  
R. K. Singh ◽  
D. Kumar ◽  
J. Fitz-Gerald
Keyword(s):  
The Other ◽  
Core Shell ◽  
The Core ◽  
Crystallographic Characteristic ◽  
Synthesis Strategy ◽  
Conformal Coatings ◽  
Interface Structures ◽  
Individual Particles ◽  
Outer Coating

ABSTRACTIn this paper we present an overview of two very different approaches to the synthesis of composite particulates which result in a “core-shell” type structure. It is shown that both these synthesis approaches result in very characteristic interface structures between the outer coating and the host particles. One synthesis strategy is to use laser ablation deposition on individual particles and the other is to “coat” particles ‘in-situ’ by taking advantage of solid state diffusional transformations. Examination of the interface between the outer shell and the core of the particle shows that textured or toptactical growth occurs and it is suggested that this unique crystallographic characteristic may be responsible for the properties offered by these engineered particulates. The applications of such engineered particulates is also discussed.

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